update version

Flash unlock validation on STM32

.github/workflows/claude-full-security-scan.yml

@@ -69,6 +69,7 @@ jobs:
       - name: Run Claude full codebase security scan
         id: claude_scan
         uses: anthropics/claude-code-action@v1
+        timeout-minutes: 30
         with:
           anthropic_api_key: ${{ secrets.CLAUDE_API_KEY }}
 
@@ -94,9 +95,8 @@ jobs:
             Do not create GitHub issues.
 
           claude_args: |
-            --max-turns 20
             --allowedTools "Read,Glob,Grep,Bash(git:*),Bash(find:*),Bash(grep:*),Bash(sed:*),Bash(cat:*)"
-            --model claude-opus-4-8
+            --model claude-opus-5
 
       - name: Prepare private security scan outputs
         if: always() && steps.claude_scan.outputs.execution_file != ''

.github/workflows/claude-pr-security-review.yml

@@ -111,4 +111,4 @@ jobs:
 
           claude_args: |
             --allowedTools "Read,Bash(cat:*),Bash(gh pr diff:*),Bash(gh pr view:*),Bash(gh pr comment:*)"
-            --model claude-opus-4-8
+            --model claude-opus-5

.github/workflows/fuzz.yml

@@ -12,13 +12,99 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        target: [fuzz, fuzz_tls]
-    name: ${{ matrix.target }}
+        ipv6: [0, 1] # fuzz code always feeds IPv6, so this fuzzes ignoring while going parallel in sync
+    name: fuzz IPV6=${{ matrix.ipv6 }}
+    env:
+      TFLAGS: -DMG_ENABLE_IPV6=${{ matrix.ipv6 }}
     steps:
     - uses: actions/checkout@v5
       with: { fetch-depth: 2 }
-    - run: make -C test ${{ matrix.target }} ARGS="-max_total_time=14400"
+    - name: Restore Combined Fuzzing Corpus
+      uses: dawidd6/action-download-artifact@v21
+      with:
+        name: combined-fuzz-corpus
+        path: test/corpus_dir
+        branch: ${{ github.base_ref || github.ref_name }}
+        search_artifacts: true
+        if_no_artifact_found: warn
+    - name: Run Matrix Fuzzers
+      run: mkdir -p test/corpus_dir && make -C test fuzz ARGS="corpus_dir -seed=${{ github.run_id }} -max_total_time=14400"
+    # Keep failures split by matrix leg so the offending input is easy to find.
+    - name: Upload Fuzz Failure Artifacts
+      if: failure()
+      uses: actions/upload-artifact@v7
+      with:
+        name: fuzz-failure-ipv6-${{ matrix.ipv6 }}
+        path: |
+          test/corpus_dir
+          test/crash-*
+          test/leak-*
+          test/oom-*
+          test/timeout-*
+        if-no-files-found: ignore
+        retention-days: 14
+    # v4 artifacts are immutable, so each parallel leg uploads its own corpus.
+    - name: Upload Corpus Shard
+      uses: actions/upload-artifact@v7
+      with:
+        name: fuzz-corpus-ipv6-${{ matrix.ipv6 }}
+        path: test/corpus_dir
+        retention-days: 14
 
-# as we're not getting access to test units causing a problem, convert from the log:
+  merge_fuzz_corpus:
+    runs-on: ubuntu-latest
+    needs: fuzz
+    name: merge fuzz corpus
+    steps:
+    # Merge both parallel fuzzing corpuses into the shared seed for next run.
+    - name: Merge Corpus Shards
+      uses: actions/upload-artifact/merge@v7
+      with:
+        name: combined-fuzz-corpus
+        pattern: fuzz-corpus-ipv6-*
+        delete-merged: true
+        retention-days: 14
+  # see NOTE
+
+  fuzz_tls:
+    runs-on: ubuntu-latest
+    name: fuzz_tls
+    env:
+      TFLAGS: -DMG_ENABLE_IPV6=0
+    steps:
+    - uses: actions/checkout@v5
+      with: { fetch-depth: 2 }
+    - name: Restore Fuzzing Corpus
+      uses: actions/cache/restore@v6
+      with:
+        path: test/corpus_dir
+        key: fuzz-corpus-${{ github.head_ref || github.ref_name }}-${{ github.run_id }}
+        restore-keys: |
+          fuzz-corpus-${{ github.head_ref || github.ref_name }}-
+          fuzz-corpus-main-
+          fuzz-corpus-
+    - name: Run Fuzzer
+      run: mkdir -p test/corpus_dir && make -C test fuzz_tls ARGS="corpus_dir -seed=${{ github.run_id }} -max_total_time=14400"
+    - name: Upload Fuzz TLS Failure Artifacts
+      if: failure()
+      uses: actions/upload-artifact@v7
+      with:
+        name: fuzz-tls-failure-artifacts
+        path: |
+          test/corpus_dir
+          test/crash-*
+          test/leak-*
+          test/oom-*
+          test/timeout-*
+        if-no-files-found: ignore
+        retention-days: 14
+    - name: Save Updated Corpus to Cache
+      uses: actions/cache/save@v6
+      with:
+        path: test/corpus_dir
+        key: fuzz-corpus-${{ github.head_ref || github.ref_name }}-${{ github.run_id }}
+
+# NOTE
+# In case we can't get access to test units causing a problem, convert from the log:
 # base64 -d > dataofdeath
 # then paste the base64 data, enter, Ctrl-D; maybe check with hexdump -C dataofdeath

.github/workflows/nightly.yml

@@ -1,7 +1,7 @@
 name: Full build
 on:
   schedule:
-    - cron: '0 22 * * *' # run at 10 PM UTC
+    - cron: '17 22 * * *' # run at 10:17 PM UTC
   # Allow manual runs
   workflow_dispatch:
 env:
@@ -51,6 +51,25 @@ jobs:
         cat log
         test/health.awk < log > json
         scp -o "StrictHostKeyChecking=no" json "root@176.9.217.245:/data/downloads/health/linux_${{ matrix.target }}_${{ matrix.cc }}_${{ matrix.ssl }}_${{ matrix.select }}_$(date +"%Y%m%d").json"
+
+  c89:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        target: [diabish, ppc_diabish]
+        ssl: ["", BUILTIN]
+    name: C89 ${{ matrix.target }} SSL=${{ matrix.ssl }}
+    env:
+      SSL: ${{ matrix.ssl }}
+      TFLAGS: -DMG_ENABLE_POLL=0 -DMG_ENABLE_EPOLL=0 -DMG_ENABLE_CHACHA20=0 -DMQTT_LOCALHOST -DNO_ZU_TEST
+    steps:
+    - uses: actions/checkout@v5
+      with: { fetch-depth: 2 }
+    - run: | # GH runners seem to overflow the 32-bit FS for the QEMU PPC (works for me in RHEL9)
+        if [[ "${{ matrix.target }}" = ppc_* ]]; then export TFLAGS="$TFLAGS -D_FILE_OFFSET_BITS=64"; fi
+        sudo apt -y update ; sudo apt -y install binfmt-support qemu-user-static && ./test/setup_mqtt_server.sh && docker run --rm --privileged multiarch/qemu-user-static --reset -p yes && make -C test ${{ matrix.target }}
+
   mip:
     runs-on: ubuntu-latest
     strategy:
@@ -59,10 +78,6 @@ jobs:
         cc: [gcc, clang, g++, clang++]
         target: [mip_test, mip_tap_test]
         ssl: ["", BUILTIN, MBEDTLS, OPENSSL, WOLFSSL]
-        # #3226: built-in TCP is currently not working with WolfSSL (builds fine)
-        exclude:
-        - ssl: WOLFSSL
-          target: mip_tap_test
     name: ${{ matrix.target }} CC=${{ matrix.cc }} SSL=${{ matrix.ssl }}
     env:
       CC: ${{ matrix.cc }}
@@ -75,25 +90,222 @@ jobs:
     - uses: webfactory/ssh-agent@v0.10.0
       with:
             ssh-private-key: ${{ secrets.HEALTH_TESTS_SSH_KEY }}
+    # WolfSSL version (5.6.6) in current GH runner (Ubuntu 24.04) is broken for EC
+    # https://github.com/wolfSSL/wolfssl/pull/10065
+    - name: Build non-broken WolfSSL version
+      if: matrix.ssl == 'WOLFSSL'
+      run: |
+        sudo apt -y update
+        sudo apt -y install autoconf automake libtool
+        git clone --depth 1 --branch v5.9.1-stable https://github.com/wolfSSL/wolfssl
+        cd wolfssl
+        ./autogen.sh
+        ./configure --prefix="$GITHUB_WORKSPACE/wolfssl-install" --enable-all
+        make -j"$(nproc)"
+        make install
+        echo "WOLFSSL=$GITHUB_WORKSPACE/wolfssl-install" >> "$GITHUB_ENV"
+        echo "LD_LIBRARY_PATH=$GITHUB_WORKSPACE/wolfssl-install/lib${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}" >> "$GITHUB_ENV"
+        if [ "${{ matrix.cc }}" = "g++" ] || [ "${{ matrix.cc }}" = "clang++" ]; then
+          echo "TFLAGS=$TFLAGS -DWOLFSSL_USE_OPTIONS_H -Wno-pedantic" >> "$GITHUB_ENV"
+        else
+          echo "TFLAGS=$TFLAGS -DWOLFSSL_USE_OPTIONS_H" >> "$GITHUB_ENV"
+        fi
     - run: if [ "${{ matrix.target }}" == "mip_tap_test" ]; then source ./test/setup_ga_network.sh ; sed -i -e "s/127.0.0.1//" test/mosquitto.conf; cat test/mosquitto.conf; ./test/setup_mqtt_server.sh; fi && sudo apt -y update ; sudo apt -y install libmbedtls-dev libwolfssl-dev && make -C test ${{ matrix.target }} > log
     - if: success() || failure()
       run: |
         cat log
         test/health.awk < log > json
         scp -o "StrictHostKeyChecking=no" json "root@176.9.217.245:/data/downloads/health/${{ matrix.target }}_${{ matrix.cc }}_${{ matrix.ssl }}_$(date +"%Y%m%d").json"
-
   mip89:
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
-      max-parallel: 1   # no parallel runs, to minimize MQTT errors
       matrix:
-        target: [mip_vc98]
-    name: mip89 ${{ matrix.target }}
+        target: [mip_vc98, mip_diabish, mip_ppc_diabish]
+        ipv6: [0, 1]
+    name: MIP C89 ${{ matrix.target }} IPV6=${{ matrix.ipv6 }}
     steps:
     - uses: actions/checkout@v5
       with: { fetch-depth: 2 }
-    - run: make -C test ${{ matrix.target }} IPV6=1
+    - run: sudo apt -y update ; sudo apt -y install binfmt-support qemu-user-static && docker run --rm --privileged multiarch/qemu-user-static --reset -p yes && make -C test ${{ matrix.target }} IPV6=${{ matrix.ipv6 }}
+  mipbe:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        target: [mip_s390, mip_port_s390, mip_ppc, mip_port_ppc, mip_mips, mip_port_mips]
+        ipv6: [0, 1]
+        ssl: ["", BUILTIN]
+    name: MIP be ${{ matrix.target }} IPV6=${{ matrix.ipv6 }} SSL=${{ matrix.ssl }}
+    env:
+      TFLAGS: -DMQTT_HOST -DIPV6_NOROUTING
+    steps:
+    - uses: actions/checkout@v5
+      with: { fetch-depth: 2 }
+    - run: |
+        sudo apt -y update ; sudo apt -y install binfmt-support qemu-user-static && docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
+        if [[ "${{ matrix.target }}" == *port* ]]; then source ./test/setup_ga_network.sh ; export ENV="-e Tmp=. -e WINEDEBUG=-all -e HOST_IP -e HOST_IPV6 -e HOST_IFC" ; sed -i -e "s/127.0.0.1//" test/mosquitto.conf; cat test/mosquitto.conf; ./test/setup_mqtt_server.sh ; make -C test port_tap_bridge ; test/port_tap_bridge & sleep 2 ; fi
+        make -C test ${{ matrix.target }} IPV6=${{ matrix.ipv6 }} SSL=${{ matrix.ssl }} MULTIREC=NO
+
+  l2:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        cc: [gcc, clang, g++, clang++]
+        target: [eth_test, ppp_test]
+        ipv6: [0, 1]
+    name: L2 ${{ matrix.target }} CC=${{ matrix.cc }} IPV6=${{ matrix.ipv6 }}
+    steps:
+    - uses: actions/checkout@v5
+      with: { fetch-depth: 2 }
+    - uses: webfactory/ssh-agent@v0.10.0
+      with:
+            ssh-private-key: ${{ secrets.HEALTH_TESTS_SSH_KEY }}
+    - run: make -C test ${{ matrix.target }} IPV6=${{ matrix.ipv6 }} CC=${{ matrix.cc }} > log
+    - if: success() || failure()
+      run: |
+        cat log
+        test/health.awk < log > json
+        scp -o "StrictHostKeyChecking=no" json "root@176.9.217.245:/data/downloads/health/${{ matrix.target }}_${{ matrix.cc }}_${{ matrix.ipv6 }}_$(date +"%Y%m%d").json"
+  l289:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        target: [eth_vc98, ppp_vc98]
+        ipv6: [0, 1]
+    name: L2 C89 ${{ matrix.target }} IPV6=${{ matrix.ipv6 }}
+    steps:
+    - uses: actions/checkout@v5
+      with: { fetch-depth: 2 }
+    - run: make -C test ${{ matrix.target }} IPV6=${{ matrix.ipv6 }}
+  l2be:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        target: [eth_s390, ppp_s390]
+        ipv6: [0, 1]
+    name: L2 be ${{ matrix.target }} IPV6=${{ matrix.ipv6 }}
+    steps:
+    - uses: actions/checkout@v5
+      with: { fetch-depth: 2 }
+    - run: sudo apt -y update ; sudo apt -y install binfmt-support qemu-user-static && docker run --rm --privileged multiarch/qemu-user-static --reset -p yes && make -C test ${{ matrix.target }} IPV6=${{ matrix.ipv6 }}
+  pppoe_vlan: # run tests, build tests performed by the l2 job may not catch runtime alignment and protocol issues, etc.
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        cc: [gcc, clang, g++, clang++]
+        ipv6: [0, 1]
+    name: PPPoE over VLAN CC=${{ matrix.cc }} IPV6=${{ matrix.ipv6 }}
+    steps:
+    - uses: actions/checkout@v5
+      with: { fetch-depth: 2 }
+    - uses: webfactory/ssh-agent@v0.10.0
+      with:
+            ssh-private-key: ${{ secrets.HEALTH_TESTS_SSH_KEY }}
+    - run: |
+        source ./test/setup_ga_network.sh
+        make -C test pppoe_tap_test CC=${{ matrix.cc }} IPV6=${{ matrix.ipv6 }} > log
+    - if: success() || failure()
+      run: |
+        cat log
+        test/health.awk < log > json
+        scp -o "StrictHostKeyChecking=no" json "root@176.9.217.245:/data/downloads/health/pppoe-vlan_${{ matrix.cc }}_${{ matrix.ipv6 }}_$(date +"%Y%m%d").json"
+
+  atcmd:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        cc: [gcc, clang, g++, clang++]
+    name: ATcmd CC=${{ matrix.cc }}
+    env:
+      IPV6: 0 # makes no sense, shorten code
+    steps:
+    - uses: actions/checkout@v5
+      with: { fetch-depth: 2 }
+    - uses: webfactory/ssh-agent@v0.10.0
+      with:
+            ssh-private-key: ${{ secrets.HEALTH_TESTS_SSH_KEY }}
+    - run: make -C test atcmd_test CC=${{ matrix.cc }} > log
+    - if: success() || failure()
+      run: |
+        cat log
+        test/health.awk < log > json
+        scp -o "StrictHostKeyChecking=no" json "root@176.9.217.245:/data/downloads/health/ATcmd_${{ matrix.cc }}_$(date +"%Y%m%d").json"
+  atcmd89:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        target: [atcmd_vc98]
+    name: ATcmd C89 ${{ matrix.target }}
+    env:
+      IPV6: 0 # makes no sense, shorten code
+    steps:
+    - uses: actions/checkout@v5
+      with: { fetch-depth: 2 }
+    - run: make -C test ${{ matrix.target }}
+  atcmdbe:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        target: [atcmd_s390]
+    name: ATcmd be ${{ matrix.target }}
+    env:
+      IPV6: 0 # makes no sense, shorten code
+    steps:
+    - uses: actions/checkout@v5
+      with: { fetch-depth: 2 }
+    - run: sudo apt -y update ; sudo apt -y install binfmt-support qemu-user-static && docker run --rm --privileged multiarch/qemu-user-static --reset -p yes && make -C test ${{ matrix.target }}
+
+  bsd:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        cc: [gcc, clang, g++, clang++]
+    name: bsd CC=${{ matrix.cc }}
+    steps:
+    - uses: actions/checkout@v5
+      with: { fetch-depth: 2 }
+    - uses: webfactory/ssh-agent@v0.10.0
+      with:
+            ssh-private-key: ${{ secrets.HEALTH_TESTS_SSH_KEY }}
+    - run: |
+        source ./test/setup_ga_network.sh
+        make -C test/bsd shm_tap_bridge
+        test/bsd/shm_tap_bridge &
+        sleep 2
+        make -C test/bsd CC=${{ matrix.cc }} > log
+    - if: success() || failure()
+      run: |
+        cat log
+        test/health.awk < log > json
+        scp -o "StrictHostKeyChecking=no" json "root@176.9.217.245:/data/downloads/health/bsd_${{ matrix.cc }}_$(date +"%Y%m%d").json"
+
+  bsdbe:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        target: [bsd_s390]
+    name: bsd be ${{ matrix.target }}
+    steps:
+    - uses: actions/checkout@v5
+      with: { fetch-depth: 2 }
+    - run: |
+        sudo apt -y update ; sudo apt -y install binfmt-support qemu-user-static && docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
+        source ./test/setup_ga_network.sh
+        make -C test port_tap_bridge
+        test/port_tap_bridge &
+        sleep 2
+        make -C test/bsd ${{ matrix.target }}
+
   s390:
     runs-on: ubuntu-latest
     strategy:
@@ -156,8 +368,6 @@ jobs:
         exclude:
         - ssl: MBEDTLS
           select: -DMG_ENABLE_POLL=0
-        - ssl: MBEDTLS                # see issue#2694
-          select: -DMG_ENABLE_POLL=1
         - ssl: OPENSSL
           select: -DMG_ENABLE_POLL=0
         - ssl: WOLFSSL
@@ -188,7 +398,7 @@ jobs:
       fail-fast: false
       max-parallel: 1   # no parallel runs, to minimize MQTT errors
       matrix:
-        target: [vc98, vc17, vc22, mingw, mingw++]
+        target: [vc98, vc17, vc22, mingw, mingw++] # current mdash/mingw image compiler does not have support for %zu; test disabled below
         ssl: ["", BUILTIN]
         select: [-DMG_ENABLE_POLL=0, -DMG_ENABLE_POLL=1]
         exclude:
@@ -197,14 +407,14 @@ jobs:
     name: windows ${{ matrix.target }} SSL=${{ matrix.ssl }} TFLAGS=${{ matrix.select }}
     env:
       SSL: ${{ matrix.ssl }}
-      TFLAGS: ${{ matrix.select }} -DMQTT_LOCALHOST -DNO_ABORT
+      TFLAGS: ${{ matrix.select }} -DMQTT_LOCALHOST -DNO_ABORT 
     steps:
     - uses: actions/checkout@v5
       with: { fetch-depth: 2 }
     - uses: webfactory/ssh-agent@v0.10.0
       with:
             ssh-private-key: ${{ secrets.HEALTH_TESTS_SSH_KEY }}
-    - run: ./test/setup_mqtt_server.sh && make -C test ${{ matrix.target }} > log
+    - run: if [ "${{ matrix.target }}" == "mingw" ]; then export TFLAGS="$TFLAGS -DNO_ZU_TEST"; fi && ./test/setup_mqtt_server.sh && make -C test ${{ matrix.target }} > log
     - if: success() || failure()
       run: |
         cat log
@@ -318,41 +528,66 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        example:
-          - path: infineon/xmc47_relax-make-baremetal-builtin
-          - path: infineon/xmc_plt2go_4400-make-baremetal-builtin
-          - path: infineon/xmc72_evk-make-baremetal-builtin
-          - path: nxp/frdm-mcxn947-make-baremetal-builtin
-          - path: nxp/frdm-mcxn947-make-freertos-builtin
-          - path: nxp/rt1020-evk-make-baremetal-builtin
-          - path: nxp/rt1060-evk-make-baremetal-builtin
-          - path: nxp/rt1170-evk-make-baremetal-builtin
-          - path: rp/pico-w
-          - path: rp/w5500-evb-pico
-          - path: rp/w55rp20-evb-pico
-          - path: rp/pico-rndis
-          - path: stm32/nucleo-f429zi/minimal
-          - path: stm32/nucleo-f746zg/minimal
-          - path: stm32/nucleo-f746zg/minimal-pppoe
-          - path: stm32/nucleo-f756zg/minimal
-          - path: stm32/nucleo-h563zi/minimal
-          - path: stm32/nucleo-h723zg/minimal
-          - path: stm32/nucleo-h743zi/minimal
-          - path: stm32/nucleo-n657x0-q/minimal
-          - path: stm32/nucleo-u5a5zj-q/minimal
-          - path: stm32/portenta-h7/minimal
-          - path: stm32/stm32h573i-dk/minimal
-          - path: stm32/stm32h747i-disco/minimal
-          - path: ti/ek-tm4c1294xl-make-baremetal-builtin
-          - path: ti/ek-tm4c1294xl-make-freertos-builtin
-    name: ${{ matrix.example.path }}
+        include:
+          - group: infineon-nxp
+            examples: |
+              infineon/xmc47_relax-make-baremetal-builtin
+              infineon/xmc_plt2go_4400-make-baremetal-builtin
+              infineon/xmc72_evk-make-baremetal-builtin
+              nxp/frdm-mcxn947-make-baremetal-builtin
+              nxp/frdm-mcxn947-make-freertos-builtin
+              nxp/rt1020-evk-make-baremetal-builtin
+              nxp/rt1060-evk-make-baremetal-builtin
+              nxp/rt1170-evk-make-baremetal-builtin
+          - group: rp-ti
+            examples: |
+              rp/pico-w
+              rp/w5500-evb-pico
+              rp/w55rp20-evb-pico
+              rp/pico-rndis
+              ti/ek-tm4c1294xl-make-baremetal-builtin
+              ti/ek-tm4c1294xl-make-freertos-builtin
+          - group: stm32-1
+            examples: |
+              stm32/nucleo-f429zi/minimal
+              stm32/nucleo-f746zg/minimal
+              stm32/nucleo-f746zg/minimal-pppoe
+              stm32/nucleo-f756zg/minimal
+              stm32/nucleo-h563zi/minimal
+              stm32/nucleo-h723zg/minimal
+          - group: stm32-2
+            examples: |
+              stm32/nucleo-h743zi/minimal
+              stm32/nucleo-n657x0-q/minimal
+              stm32/nucleo-u5a5zj-q/minimal
+              stm32/portenta-h7/minimal
+              stm32/stm32h573i-dk/minimal
+              stm32/stm32h747i-disco/minimal
+    name: wizard ARM ${{ matrix.group }}
     env:
       GO: 0
     steps:
       - uses: actions/checkout@v5
         with: { fetch-depth: 2 }
       - run: sudo apt -y update && sudo apt -y install gcc-arm-none-eabi
-      - run: make -C tutorials/${{ matrix.example.path }} build
+      - run: |
+          failed=0
+          sep=
+          examples='${{ matrix.examples }}'
+          for x in $examples; do
+            echo "========== $x =========="
+            if make -C "tutorials/$x" build; then
+              ok=true
+              echo "SUCCESS: $x"
+            else
+              ok=false
+              failed=1
+              echo "FAILURE: $x"
+            fi
+            printf 'HEALTH_DASHBOARD\t%s"%s": %s\n' "$sep" "$x" "$ok"
+            sep=,
+          done
+          exit $failed
 
 
   generic_examples:
@@ -378,40 +613,63 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        example:
-          - path: mqtt/mqtt-client/microchip/same54-xpro
-          - path: nxp/nxp-frdmk66f-freertos
-          - path: nxp/nxp-lpcxpresso54s018m-freertos
-          - path: nxp/nxp-mimxrt1020-freertos
-          - path: nxp/nxp-evkbimxrt1050-lwip-freertos
-          - path: nxp/nxp-evkmimxrt1020-lwip-freertos
-          - path: nxp/nxp-evkmimxrt1024-lwip-freertos
-          - path: nxp/nxp-evkmimxrt1060-lwip-freertos
-          - path: nxp/nxp-evkmimxrt1064-lwip-freertos
-          - path: nxp/nxp-evkmimxrt1160-cm7-lwip-freertos
-          - path: nxp/nxp-evkmimxrt1170-cm7-lwip-freertos
-          - path: nxp/nxp-frdmk64f-lwip-freertos
-          - path: nxp/nxp-frdmk66f-lwip-freertos
-          - path: nxp/nxp-lpcxpresso54018-lwip-freertos
-          - path: nxp/nxp-lpcxpresso54608-lwip-freertos
-          - path: nxp/nxp-lpcxpresso54618-lwip-freertos
-          - path: nxp/nxp-lpcxpresso54628-lwip-freertos
-          - path: nxp/nxp-twrk65f180m-lwip-freertos
-          - path: nxp/nxp-twrkv58f220m-lwip-freertos
-          - path: rp/pico-rmii
-          - path: stm32/nucleo-f746zg/minimal-rm2
-          - path: stm32/nucleo-f746zg/minimal-rndis
-          - path: stm32/nucleo-f429zi/minimal-rm2
-          - path: stm32/nucleo-f429zi/minimal-rndis
-          - path: stm32/nucleo-g031k8/minimal-w5500
-          - path: ti/ti-ek-tm4c1294xl-http-server
-          - path: ti/ek-tm4c1294xl-make-baremetal-builtin-rndis
-    name: ${{ matrix.example.path }}
+        include:
+          - group: nxp-1
+            examples: |
+              nxp/nxp-frdmk66f-freertos
+              nxp/nxp-lpcxpresso54s018m-freertos
+              nxp/nxp-mimxrt1020-freertos
+              nxp/nxp-evkbimxrt1050-lwip-freertos
+              nxp/nxp-evkmimxrt1020-lwip-freertos
+              nxp/nxp-evkmimxrt1024-lwip-freertos
+              nxp/nxp-evkmimxrt1060-lwip-freertos
+              nxp/nxp-evkmimxrt1064-lwip-freertos
+              nxp/nxp-evkmimxrt1160-cm7-lwip-freertos
+          - group: nxp-2
+            examples: |
+              nxp/nxp-evkmimxrt1170-cm7-lwip-freertos
+              nxp/nxp-frdmk64f-lwip-freertos
+              nxp/nxp-frdmk66f-lwip-freertos
+              nxp/nxp-lpcxpresso54018-lwip-freertos
+              nxp/nxp-lpcxpresso54608-lwip-freertos
+              nxp/nxp-lpcxpresso54618-lwip-freertos
+              nxp/nxp-lpcxpresso54628-lwip-freertos
+              nxp/nxp-twrk65f180m-lwip-freertos
+              nxp/nxp-twrkv58f220m-lwip-freertos
+          - group: other
+            examples: |
+              mqtt/mqtt-client/microchip/same54-xpro
+              rp/pico-rmii
+              stm32/nucleo-f746zg/minimal-rm2
+              stm32/nucleo-f746zg/minimal-rndis
+              stm32/nucleo-f429zi/minimal-rm2
+              stm32/nucleo-f429zi/minimal-rndis
+              stm32/nucleo-g031k8/minimal-w5500
+              ti/ti-ek-tm4c1294xl-http-server
+              ti/ek-tm4c1294xl-make-baremetal-builtin-rndis
+    name: generic ARM ${{ matrix.group }}
     steps:
       - uses: actions/checkout@v5
         with: { fetch-depth: 2 }
       - run: sudo apt -y update && sudo apt -y install gcc-arm-none-eabi
-      - run: make -C tutorials/${{ matrix.example.path }} build
+      - run: |
+          failed=0
+          sep=
+          examples='${{ matrix.examples }}'
+          for x in $examples; do
+            echo "========== $x =========="
+            if make -C "tutorials/$x" build; then
+              ok=true
+              echo "SUCCESS: $x"
+            else
+              ok=false
+              failed=1
+              echo "FAILURE: $x"
+            fi
+            printf 'HEALTH_DASHBOARD\t%s"%s": %s\n' "$sep" "$x" "$ok"
+            sep=,
+          done
+          exit $failed
 
   device_dashboard_examples:
     runs-on: ubuntu-latest
@@ -433,19 +691,46 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ssl: ["", -DMG_TLS=MG_TLS_BUILTIN]
-        example:
-          - path: http/device-dashboard/microchip/same54-xpro
-          - path: nxp/rt1020-evk-make-freertos-builtin
-          - path: nxp/rt1060-evk-make-freertos-builtin
-          - path: nxp/rt1170-evk-make-freertos-builtin
-          - path: renesas/ek-ra6m4-make-baremetal-builtin
-    name: ${{ matrix.example.path }} ${{ matrix.ssl }}
+        include:
+          - group: none
+            cflags: ""
+            examples: |
+              http/device-dashboard/microchip/same54-xpro
+              nxp/rt1020-evk-make-freertos-builtin
+              nxp/rt1060-evk-make-freertos-builtin
+              nxp/rt1170-evk-make-freertos-builtin
+              renesas/ek-ra6m4-make-baremetal-builtin
+          - group: builtin
+            cflags: -DMG_TLS=MG_TLS_BUILTIN
+            examples: |
+              http/device-dashboard/microchip/same54-xpro
+              nxp/rt1020-evk-make-freertos-builtin
+              nxp/rt1060-evk-make-freertos-builtin
+              nxp/rt1170-evk-make-freertos-builtin
+              renesas/ek-ra6m4-make-baremetal-builtin
+    name: device dashboard ARM ${{ matrix.group }}
     steps:
       - uses: actions/checkout@v5
         with: { fetch-depth: 2 }
       - run: sudo apt -y update && sudo apt -y install gcc-arm-none-eabi
-      - run: make -C tutorials/${{ matrix.example.path }} build CFLAGS_EXTRA="${{ matrix.ssl }}"
+      - run: |
+          failed=0
+          sep=
+          examples='${{ matrix.examples }}'
+          for x in $examples; do
+            echo "========== $x =========="
+            if make -C "tutorials/$x" build CFLAGS_EXTRA="${{ matrix.cflags }}"; then
+              ok=true
+              echo "SUCCESS: $x"
+            else
+              ok=false
+              failed=1
+              echo "FAILURE: $x"
+            fi
+            printf 'HEALTH_DASHBOARD\t%s"%s": %s\n' "$sep" "$x" "$ok"
+            sep=,
+          done
+          exit $failed
 
 #  mqtt_dashboard_examples:
 #    runs-on: ubuntu-latest

.github/workflows/nightly_retry.yml

@@ -0,0 +1,23 @@
+name: Retry failed nightly jobs
+on:
+  schedule:
+    - cron: '17 2 * * *'
+  workflow_dispatch:
+permissions:
+  actions: write
+jobs:
+  retry:
+    runs-on: ubuntu-latest
+    steps:
+    - env:
+        GH_TOKEN: ${{ github.token }}
+      run: |
+        min=$(date -u -d '5 hours ago' +%s)
+        max=$(date -u -d '2 hours ago' +%s)
+        gh api --paginate "/repos/$GITHUB_REPOSITORY/actions/workflows/nightly.yml/runs?status=failure&per_page=100" --jq '.workflow_runs[] | select(.run_attempt == 1) | [.id, .updated_at] | @tsv' |
+          while IFS=$'\t' read -r id updated; do
+            when=$(date -u -d "$updated" +%s)
+            if [ "$when" -ge "$min" ] && [ "$when" -le "$max" ]; then
+              gh api --method POST "/repos/$GITHUB_REPOSITORY/actions/runs/$id/rerun-failed-jobs"
+            fi
+          done

.github/workflows/on_demand.yml

@@ -4,35 +4,47 @@ on:
 env:
   IPV6: 0
 jobs:
-  mip:
+  atcmd:
     runs-on: ubuntu-latest
     strategy:
       fail-fast: false
       matrix:
-        cc: [gcc]
-        target: [mip_tap_test]
-        ssl: ["", BUILTIN, MBEDTLS, OPENSSL, WOLFSSL]
-        # #3226: built-in TCP is currently not working with WolfSSL (builds fine)
-        exclude:
-        - ssl: WOLFSSL
-          target: mip_tap_test
-    name: ${{ matrix.target }} CC=${{ matrix.cc }} SSL=${{ matrix.ssl }}
-    env:
-      CC: ${{ matrix.cc }}
-      SSL: ${{ matrix.ssl }}
-      TFLAGS: -DMQTT_HOST -DIPV6_NOROUTING -DNO_ABORT  # -DMQTT_HOST_NAME=\"server\"
+        cc: [gcc, clang, g++, clang++]
+    name: ATcmd CC=${{ matrix.cc }}
     steps:
     - uses: actions/checkout@v5
       with: { fetch-depth: 2 }
     - uses: webfactory/ssh-agent@v0.10.0
       with:
             ssh-private-key: ${{ secrets.HEALTH_TESTS_SSH_KEY }}
-    - run: if [ "${{ matrix.target }}" == "mip_tap_test" ]; then source ./test/setup_ga_network.sh ; export IPV6=1; sed -i -e "s/127.0.0.1//" test/mosquitto.conf; cat test/mosquitto.conf; ./test/setup_mqtt_server.sh; else export IPV6=1 ; fi && sudo apt -y update ; sudo apt -y install libmbedtls-dev libwolfssl-dev && make -C test ${{ matrix.target }} > log
+    - run: make -C test atcmd_test CC=${{ matrix.cc }} > log
     - if: success() || failure()
       run: |
         cat log
         test/health.awk < log > json
-        scp -o "StrictHostKeyChecking=no" json "root@176.9.217.245:/data/downloads/health/${{ matrix.target }}_${{ matrix.cc }}_${{ matrix.ssl }}_$(date +"%Y%m%d").json"
+        scp -o "StrictHostKeyChecking=no" json "root@176.9.217.245:/data/downloads/health/atcmd_${{ matrix.cc }}_$(date +"%Y%m%d").json"
+  atcmd89:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        target: [atcmd_vc98]
+    name: ATcmd C89 ${{ matrix.target }}
+    steps:
+    - uses: actions/checkout@v5
+      with: { fetch-depth: 2 }
+    - run: make -C test ${{ matrix.target }}
+  atcmdbe:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        target: [atcmd_s390]
+    name: ATcmd be ${{ matrix.target }}
+    steps:
+    - uses: actions/checkout@v5
+      with: { fetch-depth: 2 }
+    - run: sudo apt -y update ; sudo apt -y install binfmt-support qemu-user-static && docker run --rm --privileged multiarch/qemu-user-static --reset -p yes && make -C test ${{ matrix.target }}
 
 
 #  macos:

.github/workflows/quicktest.yml

@@ -16,8 +16,13 @@ jobs:
       fail-fast: false
       matrix:
         cc: [gcc, clang++]
-        target: [test, mip_test]
+        target: [test, mip_test, eth_test, ppp_test]
         ssl: ["", BUILTIN]
+        exclude:
+        - target: eth_test
+          ssl: BUILTIN
+        - target: ppp_test
+          ssl: BUILTIN
     name: linux ${{ matrix.target }} CC=${{ matrix.cc }} SSL=${{ matrix.ssl }}
     env:
       CC: ${{ matrix.cc }}
@@ -152,6 +157,7 @@ jobs:
           - path: stm32/nucleo-f746zg/minimal
           - path: stm32/nucleo-h563zi/minimal
           - path: stm32/nucleo-h723zg/minimal
+          - path: stm32/nucleo-h723zg/minimal-bsd
           - path: stm32/nucleo-h743zi/minimal
           - path: stm32/stm32h573i-dk/minimal
           - path: ti/ek-tm4c1294xl-make-baremetal-builtin

AGENTS.md

@@ -26,6 +26,8 @@ GitHub repo: https://github.com/cesanta/mongoose
   functionality such as HTTP, MQTT, Modbus, or device-dashboard logic.
 - Once Mongoose is integrated, desktop examples from `tutorials/http`,
   `tutorials/mqtt`, and similar directories also work on embedded systems.
+- For STM32, NXP IMXRT, RP2040/2350 use Mongoose's built-in TCP/IP stack
+- When building an STM32 project from scratch, use the closest tutorials/stm32/*/cube/*.ioc file as a base
 
 ## API prefix map
 
@@ -49,14 +51,17 @@ function signatures, structs, options, examples, and constraints.
 - `MG_OTA_*`, `mg_ota_*` - firmware OTA support
 
 
-## Integration
+## How to integrate Mongoose into an existing project
 
-Copy `mongoose.h` and `mongoose.c` into a `mongoose/` subdirectory of the
-project and add `mongoose/mongoose.c` to the build. The easiest is to
-copy from GitHub:
+Create `mongoose/` directory in your project.
+Download `mongoose.h` and `mongoose.c` into a `mongoose/` directory.
 
-https://raw.githubusercontent.com/cesanta/mongoose/refs/heads/master/mongoose.c
-https://raw.githubusercontent.com/cesanta/mongoose/refs/heads/master/mongoose.h
+```sh
+curl --fail --silent --create-dirs -o mongoose/mongoose.c https://raw.githubusercontent.com/cesanta/mongoose/refs/heads/master/mongoose.c
+curl --fail --silent --create-dirs -o mongoose/mongoose.h https://raw.githubusercontent.com/cesanta/mongoose/refs/heads/master/mongoose.h
+```
+
+Add `mongoose/mongoose.c` to the build.
 
 **Desktop/server** (Linux, macOS, Windows): two files are sufficient.
 
@@ -89,6 +94,27 @@ Minimal `mongoose_config.h` should set `MG_ARCH`. For example, for STM32:
 #define MG_ARCH MG_ARCH_CUBE
 ```
 
+## How to generate a new STM32 project from scratch
+
+Download and unzip the pre-generated project which is the closest to your MCU:
+
+- https://mongoose.ws/downloads/nucleo-h723zg-dashboard-full.zip
+- https://mongoose.ws/downloads/nucleo-f429zi-dashboard-full.zip
+- https://mongoose.ws/downloads/nucleo-h563zi-dashboard-full.zip
+- https://mongoose.ws/downloads/nucleo-f756zg-dashboard-full.zip
+- https://mongoose.ws/downloads/nucleo-n657x0-q-dashboard-full.zip
+- https://mongoose.ws/downloads/nucleo-u5a5zj-q-dashboard-full.zip
+- https://mongoose.ws/downloads/portenta-h7-dashboard-full.zip
+
+## How to generate a new RP2040 / RP2350 project from scratch
+
+Download and unzip the pre-generated project which is the closest to your MCU:
+
+- https://mongoose.ws/downloads/w5500-evb-pico-dashboard-full.zip
+- https://mongoose.ws/downloads/w55rp20-evb-pico-dashboard-full.zip
+- https://mongoose.ws/downloads/pico-w-dashboard-full.zip
+- https://mongoose.ws/downloads/pico-rndis-dashboard-full.zip
+
 ## Core API
 
 ```c
@@ -204,9 +230,11 @@ device dashboard.
 
 ### Required files
 
+The following files must exist at these exact paths, regardless of the build environment:
+
 ```
 your_project/
-├── main.c               # your code
+├── ...                  # IDE-specific project scaffolding
 └── mongoose/
     ├── mongoose.h       # single header
     ├── mongoose.c       # single source file
@@ -394,6 +422,11 @@ Each fieldset is exported via the get/set JSON-RPC interface, as well via the RE
 
 Do not use the API directly, dashboard.js interfaces with the UI via the data-* attributes.
 
+The dashboard backend must expose these exact functions: mg_dash_init() and mg_dash_poll().
+
+Do not rename, wrap, relocate, or replace these files or functions. Do not introduce alternatives such as app_dashboard_init(), app_dashboard_poll(), web/dashboard.html, or Core/Src/dashboard.c.
+
+Board-specific STM32Cube files may exist outside mongoose/, but the Mongoose dashboard files must retain the structure and API documented above.
 
 ## Filesystem
 

mongoose.h

@@ -20,7 +20,7 @@
 #ifndef MONGOOSE_H
 #define MONGOOSE_H
 
-#define MG_VERSION "7.22"
+#define MG_VERSION "7.23"
 
 #ifdef __cplusplus
 extern "C" {
@@ -46,6 +46,7 @@ extern "C" {
 #define MG_ARCH_RTTHREAD 14     // RT-Thread RTOS
 #define MG_ARCH_ARMCGT 15       // Texas Semi ARM-CGT
 #define MG_ARCH_CUBE 16	        // STM32Cube environment
+#define MG_ARCH_MCUXPRESSO 17   // MCUXpresso environment
 
 #define MG_ARCH_NEWLIB MG_ARCH_ARMGCC  // Alias, deprecate in 2025
 
@@ -314,6 +315,11 @@ extern "C" {
 #include <esp_timer.h>     // amalgamation ditching them
 #include <esp_system.h>
 #include <esp_mac.h>
+#include <esp_idf_version.h>
+#include <esp_ota_ops.h>
+#include <esp_task_wdt.h>
+#include <soc/soc.h>
+#include <soc/rtc_cntl_reg.h>
 
 #define MG_PATH_MAX 128
 
@@ -325,6 +331,57 @@ extern "C" {
 #define MG_ENABLE_DIRLIST 1
 #endif
 
+#ifndef MG_OTA_ESP32_WDT_TIMEOUT_MS
+#define MG_OTA_ESP32_WDT_TIMEOUT_MS 10000U
+#endif
+
+static inline void mg_ota_esp32_timer_start(void) {
+#if ESP_IDF_VERSION_MAJOR >= 5
+  esp_task_wdt_config_t cfg = {0};
+  esp_err_t err;
+
+  cfg.timeout_ms = MG_OTA_ESP32_WDT_TIMEOUT_MS;
+  cfg.idle_core_mask = 0;
+  cfg.trigger_panic = true;
+
+  err = esp_task_wdt_init(&cfg);
+  if (err == ESP_ERR_INVALID_STATE) esp_task_wdt_reconfigure(&cfg);
+#else
+  esp_task_wdt_init(MG_OTA_ESP32_WDT_TIMEOUT_MS / 1000U, true);
+#endif
+  esp_task_wdt_add(NULL);
+  esp_task_wdt_reset();
+}
+
+static inline uint32_t mg_ota_esp32_state_set(uint32_t state) {
+  if (state == 0) esp_ota_mark_app_valid_cancel_rollback();
+  REG_WRITE(RTC_CNTL_STORE0_REG, state);
+  return REG_READ(RTC_CNTL_STORE0_REG);
+}
+
+#define MG_OTA_STATE_GET() \
+  REG_READ(RTC_CNTL_STORE0_REG)
+
+#define MG_OTA_STATE_SET(v) mg_ota_esp32_state_set((uint32_t) (v))
+
+#ifndef MG_OTA_ROLLBACK_TIMER_START
+#define MG_OTA_ROLLBACK_TIMER_START() mg_ota_esp32_timer_start()
+#endif
+
+#ifndef MG_OTA_ROLLBACK_TIMER_FEED
+#define MG_OTA_ROLLBACK_TIMER_FEED() \
+  do {                               \
+    (void) esp_task_wdt_reset();     \
+  } while (0)
+#endif
+
+#ifndef MG_OTA_ROLLBACK
+#define MG_OTA_ROLLBACK()                                  \
+  do {                                                     \
+    (void) esp_ota_mark_app_invalid_rollback_and_reboot(); \
+  } while (0)
+#endif
+
 #endif
 
 
@@ -354,6 +411,158 @@ extern "C" {
 #endif
 
 
+#if MG_ARCH == MG_ARCH_MCUXPRESSO
+#define _POSIX_TIMERS
+
+#include <ctype.h>
+#if !defined(MG_ENABLE_LWIP) || !MG_ENABLE_LWIP
+#include <errno.h>
+#endif
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+
+// MCUXpresso-generated header, includes the SoC peripheral definitions.
+// NOTE: use angle brackets to prevent amalgamator ditching it
+#include <fsl_device_registers.h>
+
+#ifndef MG_PATH_MAX
+#define MG_PATH_MAX 100
+#endif
+
+#ifndef MG_ENABLE_DIRLIST
+#define MG_ENABLE_DIRLIST 0
+#endif
+
+#ifndef MG_ENABLE_TCPIP
+#define MG_ENABLE_TCPIP 1  // Enable built-in TCP/IP stack
+#endif
+
+#if MG_ENABLE_TCPIP && !defined(MG_ENABLE_DRIVER_IMXRT10) && \
+    !defined(MG_ENABLE_DRIVER_IMXRT11)
+#if defined(CPU_MIMXRT1021DAG5A) || defined(CPU_MIMXRT1024DAG5A) ||         \
+    defined(CPU_MIMXRT1042XJM5B) || defined(CPU_MIMXRT1052DVL6B) ||         \
+    defined(CPU_MIMXRT1062DVL6B) || defined(CPU_MIMXRT1064DVL6B) ||         \
+    defined(CPU_MIMXRT1062DVL6A) || defined(CPU_MIMXRT1064DVL6A) ||         \
+    defined(CPU_MIMXRT1062DVMAA_cm7) || defined(CPU_MIMXRT1062DVL6A_cm7) || \
+    defined(CPU_MIMXRT1062DVL6B_cm7) || defined(_MIMXRT1021_H_) ||          \
+    defined(_MIMXRT1024_H_) || defined(_MIMXRT1042_H_) ||                   \
+    defined(_MIMXRT1052_H_) || defined(_MIMXRT1062_H_) ||                   \
+    defined(_MIMXRT1064_H_)
+#define MG_ENABLE_DRIVER_IMXRT10 1
+#elif defined(CPU_MIMXRT1176DVMAA_cm7) || defined(CPU_MIMXRT1176DVMAA_cm4) || \
+    defined(_MIMXRT1176_cm7_H_) || defined(_MIMXRT1176_cm4_H_) ||             \
+    defined(_MIMXRT1176_H_)
+#define MG_ENABLE_DRIVER_IMXRT11 1
+#else
+#error Select an Ethernet driver in mongoose_config.h
+#endif
+#endif
+
+#ifndef MG_TLS
+#define MG_TLS MG_TLS_BUILTIN
+#endif
+
+#if !defined(MG_OTA) &&                                              \
+    (defined(CPU_MIMXRT1021DAG5A) || defined(CPU_MIMXRT1024DAG5A) || \
+     defined(_MIMXRT1021_H_) || defined(_MIMXRT1024_H_))
+#define MG_OTA MG_OTA_RT1020
+#elif !defined(MG_OTA) && \
+    (defined(CPU_MIMXRT1052DVL6B) || defined(_MIMXRT1052_H_))
+#define MG_OTA MG_OTA_RT1050
+#elif !defined(MG_OTA) &&                                                    \
+    (defined(CPU_MIMXRT1062DVL6B) || defined(CPU_MIMXRT1062DVL6A) ||         \
+     defined(CPU_MIMXRT1042XJM5B) || defined(_MIMXRT1042_H_) ||              \
+     defined(CPU_MIMXRT1062DVMAA_cm7) || defined(CPU_MIMXRT1062DVL6A_cm7) || \
+     defined(CPU_MIMXRT1062DVL6B_cm7) || defined(_MIMXRT1062_H_))
+#define MG_OTA MG_OTA_RT1060
+#elif !defined(MG_OTA) &&                                            \
+    (defined(CPU_MIMXRT1064DVL6B) || defined(CPU_MIMXRT1064DVL6A) || \
+     defined(_MIMXRT1064_H_))
+#define MG_OTA MG_OTA_RT1064
+#elif !defined(MG_OTA) &&                                                    \
+    (defined(CPU_MIMXRT1176DVMAA_cm7) || defined(CPU_MIMXRT1176DVMAA_cm4) || \
+     defined(_MIMXRT1176_cm7_H_) || defined(_MIMXRT1176_cm4_H_) ||           \
+     defined(_MIMXRT1176_H_))
+#define MG_OTA MG_OTA_RT1170
+#endif
+
+#ifndef MG_IRAM
+#define MG_IRAM __attribute__((noinline, section(".data_RAM2")))
+#endif
+
+#ifndef MG_SET_MAC_ADDRESS
+#if defined(MG_ENABLE_DRIVER_IMXRT11) && MG_ENABLE_DRIVER_IMXRT11
+#define MG_OCOTP_FUSES ((volatile uint32_t *) 0x40cac900)
+#else
+#define MG_OCOTP_FUSES ((volatile uint32_t *) 0x401f4410)
+#endif
+#define MG_SET_MAC_ADDRESS(mac)                                             \
+  do {                                                                      \
+    mac[0] = 2;                                                             \
+    mac[1] = (MG_OCOTP_FUSES[0] >> 0) & 255;                                \
+    mac[2] = (MG_OCOTP_FUSES[0] >> 10) & 255;                               \
+    mac[3] = ((MG_OCOTP_FUSES[0] >> 19) ^ (MG_OCOTP_FUSES[4] >> 19)) & 255; \
+    mac[4] = (MG_OCOTP_FUSES[4] >> 10) & 255;                               \
+    mac[5] = (MG_OCOTP_FUSES[4] >> 0) & 255;                                \
+  } while (0)
+#endif
+
+#ifndef MG_IMXRT_WDOG1_TIMEOUT_MS
+#define MG_IMXRT_WDOG1_TIMEOUT_MS 10000
+#endif
+
+#define MG_IMXRT_WDOG1_FEED() \
+  do {                        \
+    WDOG1->WSR = 0x5555;      \
+    WDOG1->WSR = 0xaaaa;      \
+  } while (0)
+
+#ifndef MG_OTA_ROLLBACK_TIMER_START
+#define MG_OTA_ROLLBACK_TIMER_START()                                     \
+  do {                                                                    \
+    uint16_t wt_ = (uint16_t) ((MG_IMXRT_WDOG1_TIMEOUT_MS / 500) - 1);    \
+    if ((WDOG1->WCR & WDOG_WCR_WDE_MASK) == 0) {                          \
+      WDOG1->WMCR = 0;                                                    \
+      WDOG1->WCR = (uint16_t) (WDOG_WCR_WDZST_MASK | WDOG_WCR_WDBG_MASK | \
+                               WDOG_WCR_WDE_MASK | WDOG_WCR_WDT_MASK |    \
+                               WDOG_WCR_SRS_MASK | WDOG_WCR_WDW_MASK |    \
+                               WDOG_WCR_WT(wt_));                         \
+    }                                                                     \
+    MG_IMXRT_WDOG1_FEED();                                                \
+  } while (0)
+#endif
+
+#ifndef MG_OTA_ROLLBACK_TIMER_FEED
+#define MG_OTA_ROLLBACK_TIMER_FEED() MG_IMXRT_WDOG1_FEED()
+#endif
+
+#ifndef MG_OTA_STATE_GET
+#define MG_OTA_STATE_GET() SNVS->LPGPR[0]
+#endif
+
+#ifndef MG_OTA_STATE_SET
+#define MG_OTA_STATE_SET(v)          \
+  do {                               \
+    if (SNVS->LPSR & (1u << 3)) {    \
+      SNVS->LPLVDR = 0x41736166u;    \
+      SNVS->LPSR = 1u << 3;          \
+    }                                \
+    SNVS->LPGPR[0] = (uint32_t) (v); \
+  } while (0)
+#endif
+
+#endif
+
+
 #if MG_ARCH == MG_ARCH_PICOSDK
 #if !defined(MG_ENABLE_LWIP) || !MG_ENABLE_LWIP
 #include <errno.h>
@@ -778,6 +987,7 @@ typedef int socklen_t;
 #define realpath(a, b) _fullpath((b), (a), MG_PATH_MAX)
 #define sleep(x) Sleep((x) *1000)
 #define mkdir(a, b) _mkdir(a)
+#define rmdir(a) _rmdir(a)
 #define timegm(x) _mkgmtime(x)
 
 #ifndef S_ISDIR
@@ -896,7 +1106,8 @@ static inline void *mg_calloc(size_t cnt, size_t size) {
   ((errcode) == -pdFREERTOS_ERRNO_EWOULDBLOCK || \
    (errcode) == -pdFREERTOS_ERRNO_EISCONN ||     \
    (errcode) == -pdFREERTOS_ERRNO_EINPROGRESS || \
-   (errcode) == -pdFREERTOS_ERRNO_EAGAIN)
+   (errcode) == -pdFREERTOS_ERRNO_EAGAIN ||      \
+   (errcode) == -pdFREERTOS_ERRNO_ENOSPC)
 
 #define MG_SOCK_RESET(errcode) ((errcode) == -pdFREERTOS_ERRNO_ENOTCONN)
 
@@ -1731,6 +1942,9 @@ void mg_free(void *ptr);
 // sensitive data (keys, passwords).
 void mg_bzero(volatile unsigned char *buf, size_t len);
 
+// Fixed-length constant-time byte equality. Use for MACs, tags, signatures.
+bool mg_memeq(const void *a, const void *b, size_t n);
+
 // Fills buf with len cryptographically random bytes. Uses the best available
 // hardware or OS source (hardware RNG, /dev/urandom, CryptGenRandom, etc.).
 // Falls back to rand() with an error log if no strong source is available.
@@ -1746,6 +1960,10 @@ char *mg_random_str(char *buf, size_t len);
 // a new checksum; pass the result of a prior call to extend over more data.
 uint32_t mg_crc32(uint32_t crc, const char *buf, size_t len);
 
+// Computes CRC16 (HDLC, polynomial 0x8408) over buf/len. Pass crc=0 to start
+// a new checksum; pass the result of a prior call to extend over more data.
+uint16_t mg_crc16(uint16_t crc, const char *buf, size_t len);
+
 // Returns true if path is safe to serve from the filesystem. Rejects paths
 // that start with '~' or '..', or contain a '/../' component, to prevent
 // directory traversal attacks.
@@ -1755,6 +1973,9 @@ bool mg_path_is_sane(const struct mg_str path);
 // calling context; avoid in event handlers.
 void mg_delayms(unsigned int ms);
 
+uint64_t mg_timegm(unsigned int year, unsigned int month, unsigned int day,
+                   unsigned int hour, unsigned int min, unsigned int sec);
+
 // Packs four byte values into a uint32_t in big-endian order.
 // MG_U32(1, 2, 3, 4) == 0x01020304
 #define MG_U32(a, b, c, d)                                         \
@@ -1975,6 +2196,9 @@ size_t mg_base64_update(unsigned char input_byte, char *buf, size_t len);
 size_t mg_base64_final(char *buf, size_t len);
 size_t mg_base64_encode(const unsigned char *p, size_t n, char *buf, size_t);
 size_t mg_base64_decode(const char *src, size_t n, char *dst, size_t);
+size_t mg_base64url_encode(const unsigned char *p, size_t n, char *buf,
+                           size_t);
+size_t mg_base64url_decode(const char *src, size_t n, char *dst, size_t);
 
 
 
@@ -2158,6 +2382,10 @@ struct mg_connection {
   void *pfn_data;                 // Protocol-level handler argument
   char data[MG_DATA_SIZE];        // Scratch space for protocol state; freely readable
   void *tls;                      // TLS state (internal)
+  unsigned dscp : 6;              // Differentiated Services Code Point
+#define MG_DSCP_CS(class_) ((class_) << 3)
+#define MG_DSCP_AF(class_, drop_) (((class_) << 3) | ((drop_) << 1))
+#define MG_DSCP_EF 46
   unsigned is_listening : 1;      // Listening connection; accepts inbound connections
   unsigned is_client : 1;         // Outbound connection created by mg_connect()
   unsigned is_accepted : 1;       // Inbound connection accepted from a listener
@@ -2238,6 +2466,11 @@ struct mg_connection *mg_connect(struct mg_mgr *, const char *url,
 struct mg_connection *mg_wrapfd(struct mg_mgr *mgr, int fd,
                                 mg_event_handler_t fn, void *fn_data);
 
+// Sets the 6-bit Differentiated Services Code Point for outgoing datagrams.
+// Call on MG_EV_OPEN for UDP listeners, MG_EV_CONNECT for clients, or
+// MG_EV_ACCEPT for TCP servers, before sending application data.
+bool mg_dscp(struct mg_connection *, uint8_t dscp);
+
 // Called internally after DNS resolution completes to create the OS socket
 // and initiate the TCP/IP connect. Normally not called by user code.
 void mg_connect_resolved(struct mg_connection *);
@@ -2608,6 +2841,12 @@ void mg_tls_ctx_init(struct mg_mgr *);
 void mg_tls_ctx_free(struct mg_mgr *);
 #define MG_IS_DER(buf) (((uint8_t *) (buf))[0] == 0x30)  // DER begins with 0x30
 
+#if MG_TLS == MG_TLS_BUILTIN
+// Extracts a 32-byte P-256 private scalar from EC PRIVATE KEY or PKCS#8 PRIVATE
+// KEY input. Accepts PEM or DER. Returns key size, or 0 on error.
+size_t mg_uecc_parse_private_key(struct mg_str key, uint8_t *buf, size_t len);
+#endif
+
 // Low-level IO primitives used by TLS layer
 enum { MG_IO_ERR = -1, MG_IO_WAIT = -2 };
 long mg_io_send(struct mg_connection *c, const void *buf, size_t len);
@@ -2808,28 +3047,28 @@ if 'dest' was filled with random data, or 0 if the random data could not be
 generated. The filled-in values should be either truly random, or from a
 cryptographically-secure PRNG.
 
-A correctly functioning RNG function must be set (using mg_uecc_set_rng())
-before calling mg_uecc_make_key() or mg_uecc_sign().
+A correctly functioning RNG is required before calling mg_uecc_make_key() or
+mg_uecc_sign().
 
 Setting a correctly functioning RNG function improves the resistance to
 side-channel attacks for mg_uecc_shared_secret() and
 mg_uecc_sign_deterministic().
-
-A correct RNG function is set by default when building for Windows, Linux, or OS
-X. If you are building on another POSIX-compliant system that supports
-/dev/random or /dev/urandom, you can define MG_UECC_POSIX to use the predefined
-RNG. For embedded platforms there is no predefined RNG function; you must
-provide your own.
 */
 typedef int (*MG_UECC_RNG_Function)(uint8_t *dest, unsigned size);
 
+// Mongoose: mg_uecc_make_key() and mg_uecc_sign() use mg_random() when no
+// explicit uECC RNG is installed. If mg_random() cannot provide a strong source,
+// those operations fail. Deterministic signing works without RNG, but only an
+// explicit uECC RNG enables its optional side-channel blinding.
+
 /* mg_uecc_set_rng() function.
 Set the function that will be used to generate random bytes. The RNG function
 should return 1 if the random data was generated, or 0 if the random data could
 not be generated.
 
-On platforms where there is no predefined RNG function (eg embedded platforms),
-this must be called before mg_uecc_make_key() or mg_uecc_sign() are used.
+Mongoose: this overrides the default mg_random() fallback used by
+mg_uecc_make_key() and mg_uecc_sign(). Do not call mg_uecc_set_rng() unless the
+application must provide its own cryptographic RNG.
 
 Inputs:
     rng_function - The function that will be used to generate random bytes.
@@ -3362,7 +3601,7 @@ int mg_uecc_generate_random_int(mg_uecc_word_t *random,
 
 
 
-#if MG_TLS == MG_TLS_BUILTIN
+#if MG_TLS == MG_TLS_BUILTIN && MG_ENABLE_CHACHA20
 #ifndef __PORTABLE_8439_H
 #define __PORTABLE_8439_H
 #if defined(__cplusplus)
@@ -3478,6 +3717,8 @@ int mg_rsa_crt_sign(const uint8_t *em, size_t em_len,
                     const uint8_t *q, size_t q_len,
                     const uint8_t *qInv, size_t qInv_len,
                     uint8_t *signature, size_t sig_len);
+bool mg_rsa_pkcs_verify(const uint8_t *em, size_t nlen, const uint8_t *hash,
+                        size_t hashlen);
 bool mg_rsa_verify(const uint8_t *em, size_t nlen, const uint8_t *mhash);
 #endif // TLS_RSA_H
 
@@ -3506,13 +3747,14 @@ struct mg_tls {
   mbedtls_x509_crt cert;    // Parsed certificate
   mbedtls_pk_context pk;    // Private key context
   mbedtls_ssl_context ssl;  // SSL/TLS context
-  mbedtls_ssl_config conf;  // SSL-TLS config
+  mbedtls_ssl_config conf;  // SSL/TLS config
 #ifdef MBEDTLS_SSL_SESSION_TICKETS
   mbedtls_ssl_ticket_context ticket;  // Session tickets context
 #endif
   // https://github.com/Mbed-TLS/mbedtls/blob/3b3c652d/include/mbedtls/ssl.h#L5071C18-L5076C29
   unsigned char *throttled_buf;  // see #3074
   size_t throttled_len;
+  bool check_name;  // set when hostname was set, but no CA certificate given
 };
 #endif
 
@@ -3521,11 +3763,14 @@ struct mg_tls {
 
 #include <openssl/err.h>
 #include <openssl/ssl.h>
+#include <openssl/x509v3.h>
 
 struct mg_tls {
   BIO_METHOD *bm;
   SSL_CTX *ctx;
   SSL *ssl;
+  char *name;       // matching hostname
+  bool check_name;  // set when hostname was set, but no CA certificate given
 };
 #endif
 
@@ -3954,11 +4199,12 @@ struct mg_mdns_req {
   bool is_unicast;  // True if the client requested a unicast (QU) response
 };
 
-// ev_data for MG_EV_MDNS_RESP, carrying the resolved address from an mDNS response.
+// ev_data for MG_EV_MDNS_RESP, carrying address/data from a mDNS response
 struct mg_mdns_resp {
-  struct mg_dns_rr *rr;  // Resource record from the response
+  struct mg_dns_rr *rr;  // Resource record from the response (1st in chain)
   struct mg_str name;    // Resolved hostname, without the .local suffix
   struct mg_addr addr;   // Resolved IP address
+  struct mg_dnssd_record sd; // Service Discovery data
 };
 
 // Parses a DNS query or response from buf/len into dm. Returns true on success.
@@ -3975,6 +4221,7 @@ size_t mg_dns_parse_rr(const uint8_t *buf, size_t len, size_t ofs,
 // Creates an mDNS listener on UDP multicast 224.0.0.251:5353. Registers it as
 // the manager's mDNS resolver (mgr->mdns). Fires MG_EV_MDNS_REQ for incoming
 // queries and MG_EV_MDNS_RESP for incoming responses. Returns NULL on error.
+// fn_data is a NUL-terminated server name, or NULL to pass all requests to fn.
 struct mg_connection *mg_mdns_listen(struct mg_mgr *mgr, mg_event_handler_t fn,
                                      void *fn_data);
 
@@ -4097,7 +4344,7 @@ char *mg_json_get_str(struct mg_str json, const char *path);
 
 // Decodes a hex-encoded JSON string at path into a heap-allocated byte array.
 // Sets *len to the decoded byte count. Caller must mg_free() the result.
-// Returns NULL if not found or not a string.
+// Returns NULL if not found, not a string, or not valid hexadecimal.
 char *mg_json_get_hex(struct mg_str json, const char *path, int *len);
 
 // Decodes a base64-encoded JSON string at path into a heap-allocated byte
@@ -4133,6 +4380,33 @@ size_t mg_json_next(struct mg_str obj, size_t ofs, struct mg_str *key,
 
 
 
+
+
+struct mg_jwt_opts {
+  struct mg_str claims;  // JSON payload
+  struct mg_str header;  // Extra header members, no braces; alg/typ are set
+  struct mg_str kid;     // Key ID protected header
+  struct mg_str secret;  // HS256 secret
+  const uint8_t *private_key;  // ES256 private key (MG_TLS_BUILTIN only)
+  const uint8_t *public_key;   // ES256 public key (MG_TLS_BUILTIN only)
+};
+
+// Signs JSON claims as a compact JWT. Returns JWT length, or 0 on error.
+size_t mg_jwt_sign_hs256(const struct mg_jwt_opts *opts, char *buf,
+                         size_t len);
+
+// Verifies JWT and decodes JSON claims into buf. Returns claims length, or 0.
+size_t mg_jwt_verify_hs256(struct mg_str jwt, const struct mg_jwt_opts *opts,
+                           char *buf, size_t len);
+
+size_t mg_jwt_sign_es256(const struct mg_jwt_opts *opts, char *buf,
+                         size_t len);
+size_t mg_jwt_verify_es256(struct mg_str jwt, const struct mg_jwt_opts *opts,
+                           char *buf, size_t len);
+
+
+
+
 // In-flight JSON-RPC request. Populate and pass to mg_rpc_process() to
 // dispatch, or receive one pre-filled in a handler registered with mg_rpc_add().
 struct mg_rpc_req {
@@ -4354,7 +4628,7 @@ extern void mg_mqtt_poll(struct mg_mgr *);
 //
 // This is a low-level OTA API, not intended to be called directly by users.
 // Users are provided with a higher-level API:
-// - defining MG_OTA_URL enables HTTP pull-based updates
+// - defining MG_OTA_URL enables HTTP or HTTPS pull-based updates
 // - mg_http_start_ota() enables push-based updates
 //
 // However, it is possible to use the mg_ota_* API directly. Below is the
@@ -4501,8 +4775,10 @@ enum {
     }                                                              \
   } while (0)
 
-// Pull-based OTA over HTTP. Fetches metadata_url, which must return a JSON
-// object like: { "version": "1.2.3", "url": "FIRMWARE_URL", "size": 324645 }
+// Pull-based OTA over HTTP or HTTPS. If it's HTTPS, MG_OTA_TLS_CA
+// needs to be defined. Fetches metadata_url, which must
+// return a JSON object like:
+// { "version": "1.2.3", "url": "FIRMWARE_URL", "size": 324645 }
 // If the server version differs from MG_OTA_FIRMWARE_VERSION, downloads
 // FIRMWARE_URL and performs the OTA update. fn is called on every outcome:
 // NULL on successful flash, "Same version" when already up to date, or an
@@ -4512,12 +4788,18 @@ void mg_ota_url_check(struct mg_mgr *mgr, const char *metadata_url,
                       void (*fn)(const char *error_message));
 
 // Firmware info URL for mg_ota_poll() which calls mg_ota_url_check().
-// Example:  "http://mongoose.ws/ota/u/0/ota.json". See http://mongoose.ws/ota/
+// Example: "http://mongoose.ws/ota/u/0/ota.json". See http://mongoose.ws/ota/
 // Settable in mongoose_config.h
 #ifndef MG_OTA_URL
 #define MG_OTA_URL NULL
 #endif
 
+// PEM or DER CA certificate used to authenticate an HTTPS OTA server. Set to
+// NULL to use HTTP. Set in mongoose_config.h.
+#ifndef MG_OTA_TLS_CA
+#define MG_OTA_TLS_CA NULL
+#endif
+
 // OTA status callback function for mg_ota_poll()
 #ifndef MG_OTA_STATUS_FN
 #define MG_OTA_STATUS_FN NULL
@@ -4547,8 +4829,9 @@ void mg_ota_url_check(struct mg_mgr *mgr, const char *metadata_url,
 // E.g. on STM32, uses the 96-bit MCU UID converted to a hex string.
 void mg_ota_device_id(char *buf, size_t len);
 
-// Checks for a firmware update over HTTP. Called automatically by mg_mgr_poll()
-// when MG_OTA_URL is set in mongoose_config.h. Do not call directly.
+// Checks for a firmware update over HTTP or HTTPS. Called automatically by
+// mg_mgr_poll() when MG_OTA_URL is set in mongoose_config.h. Do not call
+// directly.
 void mg_ota_poll(struct mg_mgr *);
 
 
@@ -4624,7 +4907,7 @@ bool mg_wifi_ap_stop(void);
 #if MG_ENABLE_TCPIP
 
 // no config defaults to 0 => Ethernet
-enum mg_l2type { MG_TCPIP_L2_ETH = 0, MG_TCPIP_L2_PPP, MG_TCPIP_L2_PPPoE };
+enum mg_l2type { MG_TCPIP_L2_ETH = 0, MG_TCPIP_L2_PPP, MG_TCPIP_L2_PPPoE, MG_TCPIP_L2_USER };
 
 #if defined(__DCC__)
 #pragma pack(1)

resources/specs/claude-false-positive-filtering.md

@@ -63,3 +63,5 @@
 29. Keep custom backend findings only when the issue is in Mongoose’s backend interface, default backend, documented backend contract, or common backend implementation.
 30. When uncertain, keep findings with clear external input, reachable code path, and concrete impact in Mongoose library/protocol/driver code; filter internal-access, impossible-state, local-misuse, generic-hardening, and speculative reports.
 31. For dashboard reports, do not infer unauthenticated access from a route-specific check alone; account for the broader authentication flow. Keep concrete reachable bugs such as path traversal, unsafe decoded paths, or file read/write/delete issues.
+32. Filter reports regarding DNS transaction ID predictability or lack of strict question-name matching in DNS response processing, as these are acknowledged design limitations of the current implementation.
+33. Filter reports that unauthenticated SNTP time affects TLS certificate validity when Mongoose only performs the SNTP sync if mg_boot_timestamp_ms has not already been initialized.

resources/specs/claude-security-scan-instructions.md

@@ -19,6 +19,15 @@
 
 # SECURITY CATEGORIES TO EXAMINE
 
+## Mandatory High-Risk Coverage: Built-In TLS
+
+The built-in TLS implementation (`MG_TLS_BUILTIN`) is a mandatory high-risk review target. Perform a substantial security analysis of all security-relevant built-in TLS code, including parsing, cryptographic processing, authentication and certificate validation, length and buffer handling, protocol state, cross-call behavior, and failure paths.
+
+Trace attacker-controlled TLS peer input through normal client and server execution, including traffic received before peer authentication is complete. Report any credible memory-safety, authentication, confidentiality, integrity, state-corruption, or remotely triggerable availability vulnerability.
+
+Do not set `review_completed` to `true` unless the built-in TLS implementation has been meaningfully inspected as a whole.
+
+
 **C Memory Safety and Length-Handling Vulnerabilities:**
 - Look for writes to fixed-size stack or heap buffers where the loop bound is derived from attacker-controlled protocol fields, including topic counts, header counts, chunk counts, multipart parts, DNS labels, WebSocket fragments, TCP/IP options, or filesystem path components.
 - Check all conversions between `size_t`, `int`, `long`, `uint16_t`, `uint32_t`, and signed protocol lengths. Flag integer truncation, wraparound, negative-to-large conversion, or off-by-one behavior that can affect allocation, parsing, copying, or bounds checks.

sbom.cdx.json

@@ -5,20 +5,20 @@
   "serialNumber": "urn:uuid:d3f8b1e2-4a7c-4d9e-bf2a-1c3e5f7a9b0d",
   "version": 1,
   "metadata": {
-    "timestamp": "2026-06-01T00:00:00Z",
+    "timestamp": "2026-08-12T00:00:00Z",
     "component": {
       "type": "library",
       "bom-ref": "mongoose",
       "supplier": { "name": "Cesanta Software Limited", "url": ["https://cesanta.com"] },
       "author": "Cesanta Software Limited",
       "name": "mongoose",
-      "version": "7.21",
+      "version": "7.23",
       "description": "Two-file C/C++ embedded networking library. HTTP, WebSocket, MQTT, TLS 1.3, OTA firmware updates, device dashboard. Runs on microcontrollers and desktop OS.",
       "licenses": [
         { "expression": "GPL-2.0-only" },
         { "license": { "name": "Cesanta Commercial License", "url": "https://mongoose.ws/licensing/" } }
       ],
-      "purl": "pkg:github/cesanta/mongoose@7.21",
+      "purl": "pkg:github/cesanta/mongoose@7.23",
       "externalReferences": [
         { "type": "website",          "url": "https://mongoose.ws" },
         { "type": "vcs",              "url": "https://github.com/cesanta/mongoose" },
@@ -27,7 +27,7 @@
         { "type": "distribution",     "url": "https://raw.githubusercontent.com/cesanta/mongoose/master/mongoose.c" }
       ],
       "properties": [
-        { "name": "cpe", "value": "cpe:2.3:a:cesanta:mongoose:7.21:*:*:*:*:*:*:*" }
+        { "name": "cpe", "value": "cpe:2.3:a:cesanta:mongoose:7.23:*:*:*:*:*:*:*" }
       ]
     }
   },

src/arch.h

@@ -19,6 +19,7 @@
 #define MG_ARCH_RTTHREAD 14     // RT-Thread RTOS
 #define MG_ARCH_ARMCGT 15       // Texas Semi ARM-CGT
 #define MG_ARCH_CUBE 16	        // STM32Cube environment
+#define MG_ARCH_MCUXPRESSO 17   // MCUXpresso environment
 
 #define MG_ARCH_NEWLIB MG_ARCH_ARMGCC  // Alias, deprecate in 2025
 

src/arch_esp32.h

@@ -21,6 +21,11 @@
 #include <esp_timer.h>     // amalgamation ditching them
 #include <esp_system.h>
 #include <esp_mac.h>
+#include <esp_idf_version.h>
+#include <esp_ota_ops.h>
+#include <esp_task_wdt.h>
+#include <soc/soc.h>
+#include <soc/rtc_cntl_reg.h>
 
 #define MG_PATH_MAX 128
 
@@ -32,4 +37,55 @@
 #define MG_ENABLE_DIRLIST 1
 #endif
 
+#ifndef MG_OTA_ESP32_WDT_TIMEOUT_MS
+#define MG_OTA_ESP32_WDT_TIMEOUT_MS 10000U
+#endif
+
+static inline void mg_ota_esp32_timer_start(void) {
+#if ESP_IDF_VERSION_MAJOR >= 5
+  esp_task_wdt_config_t cfg = {0};
+  esp_err_t err;
+
+  cfg.timeout_ms = MG_OTA_ESP32_WDT_TIMEOUT_MS;
+  cfg.idle_core_mask = 0;
+  cfg.trigger_panic = true;
+
+  err = esp_task_wdt_init(&cfg);
+  if (err == ESP_ERR_INVALID_STATE) esp_task_wdt_reconfigure(&cfg);
+#else
+  esp_task_wdt_init(MG_OTA_ESP32_WDT_TIMEOUT_MS / 1000U, true);
+#endif
+  esp_task_wdt_add(NULL);
+  esp_task_wdt_reset();
+}
+
+static inline uint32_t mg_ota_esp32_state_set(uint32_t state) {
+  if (state == 0) esp_ota_mark_app_valid_cancel_rollback();
+  REG_WRITE(RTC_CNTL_STORE0_REG, state);
+  return REG_READ(RTC_CNTL_STORE0_REG);
+}
+
+#define MG_OTA_STATE_GET() \
+  REG_READ(RTC_CNTL_STORE0_REG)
+
+#define MG_OTA_STATE_SET(v) mg_ota_esp32_state_set((uint32_t) (v))
+
+#ifndef MG_OTA_ROLLBACK_TIMER_START
+#define MG_OTA_ROLLBACK_TIMER_START() mg_ota_esp32_timer_start()
+#endif
+
+#ifndef MG_OTA_ROLLBACK_TIMER_FEED
+#define MG_OTA_ROLLBACK_TIMER_FEED() \
+  do {                               \
+    (void) esp_task_wdt_reset();     \
+  } while (0)
+#endif
+
+#ifndef MG_OTA_ROLLBACK
+#define MG_OTA_ROLLBACK()                                  \
+  do {                                                     \
+    (void) esp_ota_mark_app_invalid_rollback_and_reboot(); \
+  } while (0)
+#endif
+
 #endif

src/arch_mcuxpresso.h

@@ -0,0 +1,152 @@
+#pragma once
+
+#if MG_ARCH == MG_ARCH_MCUXPRESSO
+#define _POSIX_TIMERS
+
+#include <ctype.h>
+#if !defined(MG_ENABLE_LWIP) || !MG_ENABLE_LWIP
+#include <errno.h>
+#endif
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+
+// MCUXpresso-generated header, includes the SoC peripheral definitions.
+// NOTE: use angle brackets to prevent amalgamator ditching it
+#include <fsl_device_registers.h>
+
+#ifndef MG_PATH_MAX
+#define MG_PATH_MAX 100
+#endif
+
+#ifndef MG_ENABLE_DIRLIST
+#define MG_ENABLE_DIRLIST 0
+#endif
+
+#ifndef MG_ENABLE_TCPIP
+#define MG_ENABLE_TCPIP 1  // Enable built-in TCP/IP stack
+#endif
+
+#if MG_ENABLE_TCPIP && !defined(MG_ENABLE_DRIVER_IMXRT10) && \
+    !defined(MG_ENABLE_DRIVER_IMXRT11)
+#if defined(CPU_MIMXRT1021DAG5A) || defined(CPU_MIMXRT1024DAG5A) ||         \
+    defined(CPU_MIMXRT1042XJM5B) || defined(CPU_MIMXRT1052DVL6B) ||         \
+    defined(CPU_MIMXRT1062DVL6B) || defined(CPU_MIMXRT1064DVL6B) ||         \
+    defined(CPU_MIMXRT1062DVL6A) || defined(CPU_MIMXRT1064DVL6A) ||         \
+    defined(CPU_MIMXRT1062DVMAA_cm7) || defined(CPU_MIMXRT1062DVL6A_cm7) || \
+    defined(CPU_MIMXRT1062DVL6B_cm7) || defined(_MIMXRT1021_H_) ||          \
+    defined(_MIMXRT1024_H_) || defined(_MIMXRT1042_H_) ||                   \
+    defined(_MIMXRT1052_H_) || defined(_MIMXRT1062_H_) ||                   \
+    defined(_MIMXRT1064_H_)
+#define MG_ENABLE_DRIVER_IMXRT10 1
+#elif defined(CPU_MIMXRT1176DVMAA_cm7) || defined(CPU_MIMXRT1176DVMAA_cm4) || \
+    defined(_MIMXRT1176_cm7_H_) || defined(_MIMXRT1176_cm4_H_) ||             \
+    defined(_MIMXRT1176_H_)
+#define MG_ENABLE_DRIVER_IMXRT11 1
+#else
+#error Select an Ethernet driver in mongoose_config.h
+#endif
+#endif
+
+#ifndef MG_TLS
+#define MG_TLS MG_TLS_BUILTIN
+#endif
+
+#if !defined(MG_OTA) &&                                              \
+    (defined(CPU_MIMXRT1021DAG5A) || defined(CPU_MIMXRT1024DAG5A) || \
+     defined(_MIMXRT1021_H_) || defined(_MIMXRT1024_H_))
+#define MG_OTA MG_OTA_RT1020
+#elif !defined(MG_OTA) && \
+    (defined(CPU_MIMXRT1052DVL6B) || defined(_MIMXRT1052_H_))
+#define MG_OTA MG_OTA_RT1050
+#elif !defined(MG_OTA) &&                                                    \
+    (defined(CPU_MIMXRT1062DVL6B) || defined(CPU_MIMXRT1062DVL6A) ||         \
+     defined(CPU_MIMXRT1042XJM5B) || defined(_MIMXRT1042_H_) ||              \
+     defined(CPU_MIMXRT1062DVMAA_cm7) || defined(CPU_MIMXRT1062DVL6A_cm7) || \
+     defined(CPU_MIMXRT1062DVL6B_cm7) || defined(_MIMXRT1062_H_))
+#define MG_OTA MG_OTA_RT1060
+#elif !defined(MG_OTA) &&                                            \
+    (defined(CPU_MIMXRT1064DVL6B) || defined(CPU_MIMXRT1064DVL6A) || \
+     defined(_MIMXRT1064_H_))
+#define MG_OTA MG_OTA_RT1064
+#elif !defined(MG_OTA) &&                                                    \
+    (defined(CPU_MIMXRT1176DVMAA_cm7) || defined(CPU_MIMXRT1176DVMAA_cm4) || \
+     defined(_MIMXRT1176_cm7_H_) || defined(_MIMXRT1176_cm4_H_) ||           \
+     defined(_MIMXRT1176_H_))
+#define MG_OTA MG_OTA_RT1170
+#endif
+
+#ifndef MG_IRAM
+#define MG_IRAM __attribute__((noinline, section(".data_RAM2")))
+#endif
+
+#ifndef MG_SET_MAC_ADDRESS
+#if defined(MG_ENABLE_DRIVER_IMXRT11) && MG_ENABLE_DRIVER_IMXRT11
+#define MG_OCOTP_FUSES ((volatile uint32_t *) 0x40cac900)
+#else
+#define MG_OCOTP_FUSES ((volatile uint32_t *) 0x401f4410)
+#endif
+#define MG_SET_MAC_ADDRESS(mac)                                             \
+  do {                                                                      \
+    mac[0] = 2;                                                             \
+    mac[1] = (MG_OCOTP_FUSES[0] >> 0) & 255;                                \
+    mac[2] = (MG_OCOTP_FUSES[0] >> 10) & 255;                               \
+    mac[3] = ((MG_OCOTP_FUSES[0] >> 19) ^ (MG_OCOTP_FUSES[4] >> 19)) & 255; \
+    mac[4] = (MG_OCOTP_FUSES[4] >> 10) & 255;                               \
+    mac[5] = (MG_OCOTP_FUSES[4] >> 0) & 255;                                \
+  } while (0)
+#endif
+
+#ifndef MG_IMXRT_WDOG1_TIMEOUT_MS
+#define MG_IMXRT_WDOG1_TIMEOUT_MS 10000
+#endif
+
+#define MG_IMXRT_WDOG1_FEED() \
+  do {                        \
+    WDOG1->WSR = 0x5555;      \
+    WDOG1->WSR = 0xaaaa;      \
+  } while (0)
+
+#ifndef MG_OTA_ROLLBACK_TIMER_START
+#define MG_OTA_ROLLBACK_TIMER_START()                                     \
+  do {                                                                    \
+    uint16_t wt_ = (uint16_t) ((MG_IMXRT_WDOG1_TIMEOUT_MS / 500) - 1);    \
+    if ((WDOG1->WCR & WDOG_WCR_WDE_MASK) == 0) {                          \
+      WDOG1->WMCR = 0;                                                    \
+      WDOG1->WCR = (uint16_t) (WDOG_WCR_WDZST_MASK | WDOG_WCR_WDBG_MASK | \
+                               WDOG_WCR_WDE_MASK | WDOG_WCR_WDT_MASK |    \
+                               WDOG_WCR_SRS_MASK | WDOG_WCR_WDW_MASK |    \
+                               WDOG_WCR_WT(wt_));                         \
+    }                                                                     \
+    MG_IMXRT_WDOG1_FEED();                                                \
+  } while (0)
+#endif
+
+#ifndef MG_OTA_ROLLBACK_TIMER_FEED
+#define MG_OTA_ROLLBACK_TIMER_FEED() MG_IMXRT_WDOG1_FEED()
+#endif
+
+#ifndef MG_OTA_STATE_GET
+#define MG_OTA_STATE_GET() SNVS->LPGPR[0]
+#endif
+
+#ifndef MG_OTA_STATE_SET
+#define MG_OTA_STATE_SET(v)          \
+  do {                               \
+    if (SNVS->LPSR & (1u << 3)) {    \
+      SNVS->LPLVDR = 0x41736166u;    \
+      SNVS->LPSR = 1u << 3;          \
+    }                                \
+    SNVS->LPGPR[0] = (uint32_t) (v); \
+  } while (0)
+#endif
+
+#endif

src/arch_win32.h

@@ -159,6 +159,7 @@ typedef int socklen_t;
 #define realpath(a, b) _fullpath((b), (a), MG_PATH_MAX)
 #define sleep(x) Sleep((x) *1000)
 #define mkdir(a, b) _mkdir(a)
+#define rmdir(a) _rmdir(a)
 #define timegm(x) _mkgmtime(x)
 
 #ifndef S_ISDIR

src/base64.c

@@ -12,16 +12,16 @@ static int mg_base64_encode_single(int c) {
   }
 }
 
-static int mg_base64_decode_single(int c) {
+static int base64_decode_single(int c, char plus, char slash) {
   if (c >= 'A' && c <= 'Z') {
     return c - 'A';
   } else if (c >= 'a' && c <= 'z') {
     return c + 26 - 'a';
   } else if (c >= '0' && c <= '9') {
     return c + 52 - '0';
-  } else if (c == '+') {
+  } else if (c == plus) {
     return 62;
-  } else if (c == '/') {
+  } else if (c == slash) {
     return 63;
   } else if (c == '=') {
     return 64;
@@ -30,6 +30,14 @@ static int mg_base64_decode_single(int c) {
   }
 }
 
+static int mg_base64_decode_single(int c) {
+  return base64_decode_single(c, '+', '/');
+}
+
+static int mg_base64url_decode_single(int c) {
+  return base64_decode_single(c, '-', '_');
+}
+
 size_t mg_base64_update(unsigned char ch, char *to, size_t n) {
   unsigned long rem = (n & 3) % 3;
   if (rem == 0) {
@@ -91,3 +99,41 @@ fail:
   if (dl > 0) dst[0] = '\0';
   return 0;
 }
+
+size_t mg_base64url_encode(const unsigned char *p, size_t n, char *to,
+                           size_t dl) {
+  size_t i, len = mg_base64_encode(p, n, to, dl);
+  if (len == 0) return 0;
+  for (i = 0; i < len; i++) {
+    if (to[i] == '+') {
+      to[i] = '-';
+    } else if (to[i] == '/') {
+      to[i] = '_';
+    }
+  }
+  while (len > 0 && to[len - 1] == '=') to[--len] = '\0';
+  return len;
+}
+
+size_t mg_base64url_decode(const char *src, size_t n, char *dst, size_t dl) {
+  size_t i, len = 0;
+  unsigned int bits = 0, v = 0;
+  if (dl == 0 || (n & 3) == 1) goto fail;
+  for (i = 0; src != NULL && i < n; i++) {
+    int c = mg_base64url_decode_single(src[i]);
+    if (c == 64) break;
+    if (c < 0) goto fail;
+    v = (v << 6) | (unsigned int) c;
+    bits += 6;
+    if (bits >= 8) {
+      bits -= 8;
+      if (len + 1 >= dl) goto fail;
+      dst[len++] = (char) ((v >> bits) & 255U);
+    }
+  }
+  dst[len] = '\0';
+  return len;
+fail:
+  if (dl > 0) dst[0] = '\0';
+  return 0;
+}

src/base64.h

@@ -4,3 +4,6 @@ size_t mg_base64_update(unsigned char input_byte, char *buf, size_t len);
 size_t mg_base64_final(char *buf, size_t len);
 size_t mg_base64_encode(const unsigned char *p, size_t n, char *buf, size_t);
 size_t mg_base64_decode(const char *src, size_t n, char *dst, size_t);
+size_t mg_base64url_encode(const unsigned char *p, size_t n, char *buf,
+                           size_t);
+size_t mg_base64url_decode(const char *src, size_t n, char *dst, size_t);

src/bsd.c

@@ -2,6 +2,67 @@
 
 #if MG_ENABLE_BSD_SOCKETS
 
+// Queue-based BSD shim is currently TCP/SOCK_STREAM only. UDP/SOCK_DGRAM would
+// need datagram boundaries, e.g. datagram queues or SOD/EOD framing.
+// Unconnected UDP also needs per-packet peer addresses for sendto()/recvfrom().
+// It is also IPv4-only: transports store sockaddr_in and build IPv4 URLs.
+
+#ifndef MG_ENABLE_BSD_LOG
+#define MG_ENABLE_BSD_LOG 0
+#define bsd_log(type, tag, a, b, c, n)
+#else
+#define MG_BSD_LOG_SOCK 1
+#define MG_BSD_LOG_ACCEPT 2
+#define MG_BSD_LOG_CLOSE 3
+#define MG_BSD_LOG_TRANSPORT 4
+#define MG_BSD_LOG_RESULT 5
+#define MG_BSD_LOG_CONNECT 6
+// Type is always a constant, so optimised builds fold the switch to one log.
+#define bsd_log(type, tag, a, b, c, n)                                       \
+  do {                                                                       \
+    switch (type) {                                                          \
+      case MG_BSD_LOG_SOCK: {                                                \
+        struct mg_bsd_sock *log_s = (struct mg_bsd_sock *) (a);              \
+        MG_DEBUG(("SOCK %s %ld %p", tag, (long) (n), log_s->t));             \
+        break;                                                               \
+      }                                                                      \
+      case MG_BSD_LOG_ACCEPT: {                                              \
+        struct mg_connection *log_mc = (struct mg_connection *) (a);         \
+        if ((n) >= 0) {                                                      \
+          MG_DEBUG(("ACCEPT %lu %p %u %ld", log_mc->id, c,                   \
+                   (unsigned) mg_ntohs(log_mc->rem.port), (long) (n)));      \
+        } else {                                                             \
+          MG_DEBUG(("ACCEPT %lu %p %u", log_mc->id, c,                       \
+                   (unsigned) mg_ntohs(log_mc->rem.port)));                  \
+        }                                                                    \
+        break;                                                               \
+      }                                                                      \
+      case MG_BSD_LOG_CLOSE: {                                               \
+        struct mg_connection *log_mc = (struct mg_connection *) (a);         \
+        if ((n) >= 0) MG_INFO(("CLOSE %s %lu %p %ld", tag, log_mc->id, b,    \
+                               (long) (n)));                                 \
+        else MG_DEBUG(("CLOSE %s %lu %p", tag, log_mc->id, b));              \
+        break;                                                               \
+      }                                                                      \
+      case MG_BSD_LOG_TRANSPORT:                                             \
+        if ((n) >= 0) MG_INFO(("TRANSP %s %p %ld", tag, a, (long) (n)));     \
+        else MG_DEBUG(("TRANSP %s %p", tag, a));                             \
+        break;                                                               \
+      case MG_BSD_LOG_RESULT:                                                \
+        MG_DEBUG(("RESULT %s %p %ld", tag, a, (long) (n)));                  \
+        break;                                                               \
+      case MG_BSD_LOG_CONNECT:                                               \
+        if ((c) != NULL) {                                                    \
+          MG_DEBUG(("CONNECT %s %p %p %s %ld", tag, a, b,                    \
+                    (const char *) (c), (long) (n)));                        \
+        } else {                                                             \
+          MG_DEBUG(("CONNECT %s %p %p %ld", tag, a, b, (long) (n)));         \
+        }                                                                    \
+        break;                                                               \
+    }                                                                        \
+  } while (0)
+#endif
+
 struct mg_bsd_sock {
   void *t;                  // opaque transport handle
   int fd;
@@ -39,12 +100,12 @@ static void release_sock(int fd) {
   if (*p) *p = (*p)->next;
 }
 
-
 int socket(int domain, int type, int proto) {
   struct mg_bsd_sock *s = (struct mg_bsd_sock *) calloc(1, sizeof(*s));
   if (!s) { errno = ENOMEM; return -1; }
   s->t = mg_bsd_transport_new(domain, type, proto);
-  if (!s->t || alloc_sock(s) < 0) { free(s); errno = ENOMEM; return -1; }
+  if (!s->t) { free(s); return -1; }
+  if (alloc_sock(s) < 0) { mg_bsd_transport_free(s->t); free(s); errno = ENOMEM; return -1; }
   s->domain = domain; s->type = type; s->proto = proto;
   return s->fd;
 }
@@ -66,11 +127,12 @@ int listen(int fd, int backlog) {
 int accept(int fd, struct sockaddr *addr, socklen_t *addrlen) {
   struct mg_bsd_sock *ls = get(fd);
   if (!ls) return -1;
-  struct sockaddr_in peer = {0};
+  struct sockaddr_in peer;
+  memset(&peer, 0, sizeof(peer));
   void *t = mg_bsd_transport_accept(ls->t, &peer, ls->nonblock);
-  if (!t) { if (ls->nonblock) errno = EAGAIN; return -1; }
+  if (!t) return -1; // errno was set by transport_accept()
   struct mg_bsd_sock *ns = (struct mg_bsd_sock *) calloc(1, sizeof(*ns));
-  if (!ns || alloc_sock(ns) < 0) { mg_bsd_transport_free(t); free(ns); errno = ENOMEM; return -1; }
+  if (!ns || alloc_sock(ns) < 0) { mg_bsd_transport_close(t); free(ns); errno = ENOMEM; return -1; }
   ns->t = t; ns->domain = ls->domain; ns->type = ls->type; ns->peer = peer;
   if (addr && addrlen) {
     size_t sz = sizeof(peer) < *addrlen ? sizeof(peer) : *addrlen;
@@ -101,22 +163,16 @@ ssize_t recv(int fd, void *buf, size_t len, int flags) {
 
 ssize_t sendto(int fd, const void *buf, size_t len, int flags,
                       const struct sockaddr *dest, socklen_t addrlen) {
-  (void) dest; (void) addrlen;
-  return send(fd, buf, len, flags);
+  (void) fd; (void) buf; (void) len; (void) flags; (void) dest; (void) addrlen;
+  errno = EPROTONOSUPPORT;
+  return -1;
 }
 
 ssize_t recvfrom(int fd, void *buf, size_t len, int flags,
                         struct sockaddr *src, socklen_t *addrlen) {
-  ssize_t n = recv(fd, buf, len, flags);
-  if (n > 0 && src && addrlen) {
-    struct mg_bsd_sock *s = get(fd);
-    if (s) {
-      size_t sz = sizeof(s->peer) < *addrlen ? sizeof(s->peer) : *addrlen;
-      memcpy(src, &s->peer, sz);
-      *addrlen = (socklen_t) sizeof(s->peer);
-    }
-  }
-  return n;
+  (void) fd; (void) buf; (void) len; (void) flags; (void) src; (void) addrlen;
+  errno = EPROTONOSUPPORT;
+  return -1;
 }
 
 ssize_t write(int fd, const void *buf, size_t len) { return send(fd, buf, len, 0); }
@@ -125,7 +181,9 @@ ssize_t read(int fd, void *buf, size_t len) { return recv(fd, buf, len, 0); }
 int close(int fd) {
   struct mg_bsd_sock *s = get(fd);
   if (!s) return -1;
+  bsd_log(MG_BSD_LOG_SOCK, "CLOSE", s, NULL, NULL, (long) fd);
   mg_bsd_transport_close(s->t);
+  bsd_log(MG_BSD_LOG_SOCK, "FREE", s, NULL, NULL, (long) fd);
   release_sock(fd);
   free(s);
   return 0;
@@ -193,7 +251,8 @@ void freeaddrinfo(struct addrinfo *res) { (void) res; }
 #endif
 
 int inet_pton(int af, const char *src, void *dst) {
-  struct mg_addr a = {0};
+  struct mg_addr a;
+  memset(&a, 0, sizeof(a));
   if (af == AF_INET && mg_aton(mg_str_s(src), &a)) { memcpy(dst, &a.addr.ip4, 4); return 1; }
   return 0;
 }
@@ -208,7 +267,8 @@ const char *inet_ntop(int af, const void *src, char *dst, socklen_t size) {
 }
 
 in_addr_t inet_addr(const char *cp) {
-  struct mg_addr a = {0};
+  struct mg_addr a;
+  memset(&a, 0, sizeof(a));
   return mg_aton(mg_str_s(cp), &a) ? a.addr.ip4 : (in_addr_t) -1;
 }
 
@@ -239,6 +299,9 @@ uint32_t ntohl(uint32_t n) { return mg_htonl(n); }
 #ifndef MG_BSD_Q_DEPTH
 #define MG_BSD_Q_DEPTH 4
 #endif
+#ifndef MG_BSD_ACCEPT_MS
+#define MG_BSD_ACCEPT_MS 3000  // Timeout for accept queue handoff
+#endif
 
 struct mg_bsd_chunk { uint8_t data[MG_BSD_CHUNK_SIZE]; uint16_t len; };
 
@@ -248,7 +311,11 @@ struct mg_xport {
   QueueHandle_t send_q;     // task2 writes in send(), task1 drains on MG_EV_POLL
   QueueHandle_t accept_q;   // task1 writes on MG_EV_ACCEPT, task2 reads in accept()
   struct sockaddr_in peer;
+  uint16_t rx_off;
+  uint64_t accept_expire;
+  int err;
   bool closed;
+  bool orphan;  // accepted connection not handed to socket owner
   TaskHandle_t connect_waiter;  // task blocked in connect(), woken by MG_EV_CONNECT
   int *connect_result;          // where to store 0/−1 connect outcome
 };
@@ -264,17 +331,48 @@ struct mg_bsd_cmd {
 
 static QueueHandle_t s_cmd_q;
 
-// Single-slot DNS resolve state (not reentrant, sufficient for demos)
-static struct { struct mg_addr addr; bool done, error; TaskHandle_t caller; } s_resolve;
+static bool bsd_qsend(QueueHandle_t q, const void *item, TickType_t ticks,
+                      bool reserve) {
+  BaseType_t ok = pdFALSE;
+  if (!reserve || uxQueueSpacesAvailable(q) > 1) ok = xQueueSend(q, item, ticks);
+  if (ok != pdTRUE) MG_ERROR(("%p", q));
+  return ok == pdTRUE;
+}
+
+static bool xport_accept(struct mg_xport *x) {
+  if (bsd_qsend(x->accept_q, &x, 0, true)) {
+    x->orphan = false; // not an orphan anymore
+    x->accept_q = NULL;
+    return true;
+  }
+  return false; // still an orphan, retry later
+}
+
+// static DNS resolve state; not reentrant (see below)
+static struct { struct mg_addr addr; bool error; TaskHandle_t caller; } s_resolve;
+// gethostbyname statics (official isn't reentrant anyway, and is obsolete)
+static struct hostent s_hostent;
+static char *s_h_aliases[1];
+static char *s_h_addr_list[2];
+static uint32_t s_h_addr;
+static char s_h_name[64];
 
 static void resolve_cb(struct mg_connection *c, int ev, void *ev_data) {
-  if (ev == MG_EV_RESOLVE) { s_resolve.addr = c->rem; s_resolve.done = true; c->is_closing = 1; }
-  else if ((ev == MG_EV_ERROR || ev == MG_EV_CLOSE) && !s_resolve.done) s_resolve.error = true;
-  if ((s_resolve.done || s_resolve.error) && s_resolve.caller) {
-    TaskHandle_t h = s_resolve.caller;
-    s_resolve.caller = NULL;  // prevent double-notify on subsequent MG_EV_CLOSE
-    xTaskNotifyGive(h);
+  bool notify = false;
+  if (ev == MG_EV_RESOLVE) {
+    s_resolve.addr = c->rem;
+    c->is_closing = 1;
+    MG_DEBUG(("%lu resolved", c->id));
+    notify = true;
+  } else if (ev == MG_EV_ERROR) {
+    s_resolve.error = true;
+    MG_DEBUG(("%lu failed", c->id));
+    notify = true;
+  } else if (ev == MG_EV_CLOSE) {
+    s_resolve.caller = NULL;  // The resolver connection has fully unwound.
+    MG_DEBUG(("%lu done", c->id));
   }
+  if (notify) xTaskNotifyGive(s_resolve.caller);
   (void) ev_data;
 }
 
@@ -282,9 +380,11 @@ static void resolve_cb(struct mg_connection *c, int ev, void *ev_data) {
 static struct mg_xport *xport_alloc(void) {
   struct mg_xport *x = (struct mg_xport *) calloc(1, sizeof(*x));
   if (!x) return NULL;
-  x->recv_q = xQueueCreate(MG_BSD_Q_DEPTH, sizeof(struct mg_bsd_chunk));
+  // +1 keeps a terminal EOF/error slot for MG_EV_CLOSE
+  x->recv_q = xQueueCreate(MG_BSD_Q_DEPTH + 1, sizeof(struct mg_bsd_chunk));
   x->send_q = xQueueCreate(MG_BSD_Q_DEPTH, sizeof(struct mg_bsd_chunk));
   if (!x->recv_q || !x->send_q) { mg_bsd_transport_free(x); return NULL; }
+  x->orphan = true; // haven't attached this connection to its socket
   return x;
 }
 
@@ -294,51 +394,101 @@ static void xport_ev(struct mg_connection *c, int ev, void *ev_data) {
 
   if (ev == MG_EV_ACCEPT) {
     // c is the new accepted connection; x is the listening transport
+    bool ok;
     struct mg_xport *nx = xport_alloc();
-    if (!nx) { c->is_closing = 1; return; }
+    if (!nx) { c->fn_data = NULL; mg_error(c, "accept OOM"); return; }
     nx->c = c;
+    nx->accept_q = x->accept_q;
+    nx->accept_expire = mg_millis() + MG_BSD_ACCEPT_MS;
     nx->peer.sin_family = AF_INET;
     nx->peer.sin_port = c->rem.port;
     memcpy(&nx->peer.sin_addr, &c->rem.addr.ip4, 4);
     c->fn_data = nx;
-    xQueueSend(x->accept_q, &nx, 0);
-  } else if (ev == MG_EV_READ && x->recv_q) {
-    // Drain c->recv into recv_q in fixed-size chunks; task1 owns c->recv
-    size_t off = 0;
-    while (off < c->recv.len) {
+    ok = xport_accept(nx); // leaves orphaned on failure, retry on POLL
+    bsd_log(MG_BSD_LOG_ACCEPT, NULL, c, x, nx, ok ? 1 : 0);
+  } else if (ev == MG_EV_POLL && x->orphan && x->accept_q) {
+    if (uxQueueSpacesAvailable(x->accept_q) > 1 && xport_accept(x)) {
+      bsd_log(MG_BSD_LOG_ACCEPT, NULL, c, NULL, x, 1);
+    } else if (mg_millis() > x->accept_expire) { // retried enough, give up
+      x->err = EIO;
+      mg_error(c, "accept_q");
+    }
+  } else if (ev == MG_EV_READ || ev == MG_EV_POLL) {
+    if (x->recv_q) { // let POLL resume abandoned READ processing on full queue
+      // Drain c->recv into recv_q in fixed-size chunks; task1 owns c->recv
+      size_t off = 0;
+      while (off < c->recv.len) {
+        struct mg_bsd_chunk chunk;
+        size_t n = c->recv.len - off;
+        if (n > MG_BSD_CHUNK_SIZE) n = MG_BSD_CHUNK_SIZE;
+        memcpy(chunk.data, c->recv.buf + off, n);
+        chunk.len = (uint16_t) n;
+        if (uxQueueSpacesAvailable(x->recv_q) <= 1 ||
+            !bsd_qsend(x->recv_q, &chunk, 0, false)) break;  // retry later
+        off += n;
+      }
+      mg_iobuf_del(&c->recv, 0, off);
+    }
+    if (ev == MG_EV_POLL && x->send_q) {
+      // Drain send_q → mg_send(); task1 owns c
       struct mg_bsd_chunk chunk;
-      size_t n = c->recv.len - off;
-      if (n > MG_BSD_CHUNK_SIZE) n = MG_BSD_CHUNK_SIZE;
-      memcpy(chunk.data, c->recv.buf + off, n);
-      chunk.len = (uint16_t) n;
-      xQueueSend(x->recv_q, &chunk, portMAX_DELAY);
-      off += n;
+      while (xQueuePeek(x->send_q, &chunk, 0) == pdTRUE) {
+        if (!mg_send(c, chunk.data, chunk.len)) break;  // retry later
+        xQueueReceive(x->send_q, &chunk, 0);
+      }
     }
-    mg_iobuf_del(&c->recv, 0, c->recv.len);
-  } else if (ev == MG_EV_POLL && x->send_q) {
-    // Drain send_q → mg_send(); task1 owns c
-    struct mg_bsd_chunk chunk;
-    while (xQueueReceive(x->send_q, &chunk, 0) == pdTRUE)
-      mg_send(c, chunk.data, chunk.len);
   } else if (ev == MG_EV_CONNECT) {
     // Outgoing connection established: wake the task blocked in connect()
     if (x->connect_waiter) {
+      bsd_log(MG_BSD_LOG_CONNECT, "OK", x, c, NULL, 0);
       if (x->connect_result) *x->connect_result = 0;
       TaskHandle_t h = x->connect_waiter;
       x->connect_waiter = NULL; x->connect_result = NULL;
       xTaskNotifyGive(h);
     }
+  } else if (ev == MG_EV_ERROR) {   // remember error condition
+    if (x->err == 0) x->err = EIO;  // and let CLOSE handle it
+    bsd_log(MG_BSD_LOG_CLOSE, "ERR", c, x, NULL, (long) x->err);
   } else if (ev == MG_EV_CLOSE) {
+    bsd_log(MG_BSD_LOG_CLOSE, "IN", c, x, NULL, -1);
     x->c = NULL; x->closed = true; c->fn_data = NULL;
     // If connect() is still waiting, signal failure
     if (x->connect_waiter) {
+      bsd_log(MG_BSD_LOG_CONNECT, "FAIL", x, c, NULL, -1);
       if (x->connect_result) *x->connect_result = -1;
       TaskHandle_t h = x->connect_waiter;
       x->connect_waiter = NULL; x->connect_result = NULL;
       xTaskNotifyGive(h);
+      // The notified task owns the transport and can close/free it immediately.
+      return;
     }
-    if (x->recv_q) { struct mg_bsd_chunk eof = {.len = 0}; xQueueSend(x->recv_q, &eof, 0); }
-    if (x->accept_q) { struct mg_xport *nil = NULL; xQueueSend(x->accept_q, &nil, 0); }
+    if (x->orphan) { // connection --> socket attachment failed
+      x->accept_q = NULL; // borrowed from listener; do not delete it here
+      bsd_log(MG_BSD_LOG_CLOSE, "FREE", c, x, NULL, -1);
+      mg_bsd_transport_free(x); // connection closed, release resources
+      return;
+    }
+    if (x->recv_q) {
+      struct mg_bsd_chunk eof;
+      bool ok;
+      memset(&eof, 0, sizeof(eof));
+      eof.len = 0;
+      ok = bsd_qsend(x->recv_q, &eof, 0, false);
+      bsd_log(MG_BSD_LOG_CLOSE, "EOF>", c, x, NULL, ok ? 1 : 0);
+      if (!ok) MG_ERROR(("recv_q close notification failed"));
+      // recv() wakeup transfers control to the transport owner.
+      return;
+    }
+    if (x->accept_q) {
+      struct mg_xport *nil = NULL;
+      bool ok;
+      ok = bsd_qsend(x->accept_q, &nil, 0, false);
+      bsd_log(MG_BSD_LOG_CLOSE, "ACCEPT>", c, x, NULL, ok ? 1 : 0);
+      if (!ok) MG_ERROR(("accept_q close notification failed"));
+      // accept() wakeup transfers control to the transport owner.
+      return;
+    }
+    bsd_log(MG_BSD_LOG_CLOSE, "OUT", c, x, NULL, -1);
   }
   (void) ev_data;
 }
@@ -357,36 +507,52 @@ void mg_bsd_poll(struct mg_mgr *mgr) {
       cmd.x->c = c;
       *cmd.result = c ? 0 : -1;
     } else if (cmd.type == BSD_CMD_CLOSE) {
+      bsd_log(MG_BSD_LOG_TRANSPORT, "CMD", cmd.x, NULL, NULL, -1);
       if (cmd.x->c) {
         cmd.x->c->fn_data = NULL;
         cmd.x->c->is_draining = 1;
+        cmd.x->c = NULL;
       }
+      cmd.x->closed = true;
       *cmd.result = 0;
     } else if (cmd.type == BSD_CMD_CONNECT) {
       cmd.x->connect_waiter = cmd.caller;
       cmd.x->connect_result = cmd.result;
       struct mg_connection *c = mg_connect(mgr, cmd.url, xport_ev, cmd.x);
+      bsd_log(MG_BSD_LOG_CONNECT, "NEW", cmd.x, c, cmd.url, c ? 1 : 0);
       cmd.x->c = c;
       if (!c) { *cmd.result = -1; cmd.x->connect_waiter = NULL; cmd.x->connect_result = NULL; }
       else notify = false;  // xport_ev notifies when connected or on error
     } else if (cmd.type == BSD_CMD_RESOLVE) {
-      s_resolve.done = s_resolve.error = false;
+      s_resolve.error = false;
       s_resolve.caller = cmd.caller;
-      char url[80];
-      snprintf(url, sizeof(url), "tcp://%s:0", cmd.url);
-      if (!mg_connect(mgr, url, resolve_cb, NULL)) s_resolve.error = true;
-      else notify = false;  // resolve_cb notifies when done
+      struct mg_connection *c;
+      c = mg_alloc_conn(mgr);
+      if (c == NULL) {
+      } else {
+        c->fn = resolve_cb;
+        LIST_ADD_HEAD(struct mg_connection, &mgr->conns, c);
+        mg_call(c, MG_EV_OPEN, NULL);
+        MG_DEBUG(("%lu resolve %s", c->id, cmd.url));
+        mg_resolve(c, cmd.url);
+        notify = false;  // resolve_cb notifies when done
+      }
     }
     if (notify) xTaskNotifyGive(cmd.caller);
   }
 }
 
 void *mg_bsd_transport_new(int domain, int type, int proto) {
-  (void) domain; (void) type; (void) proto;
-  // For socket() calls: allocate accept_q only; recv/send added when needed
+  if (domain != AF_INET || type != SOCK_STREAM ||
+      (proto != 0 && proto != IPPROTO_TCP)) {
+    errno = EPROTONOSUPPORT;
+    return NULL;
+  }
+  // For socket() calls: allocate accept_q only; recv/send added when needed.
+  // +1 keeps a terminal slot for MG_EV_CLOSE without blocking Mongoose.
   struct mg_xport *x = (struct mg_xport *) calloc(1, sizeof(*x));
   if (!x) return NULL;
-  x->accept_q = xQueueCreate(MG_BSD_BACKLOG, sizeof(struct mg_xport *));
+  x->accept_q = xQueueCreate(MG_BSD_BACKLOG + 1, sizeof(struct mg_xport *));
   if (!x->accept_q) { free(x); return NULL; }
   return x;
 }
@@ -394,6 +560,7 @@ void *mg_bsd_transport_new(int domain, int type, int proto) {
 void mg_bsd_transport_free(void *t) {
   struct mg_xport *x = (struct mg_xport *) t;
   if (!x) return;
+  bsd_log(MG_BSD_LOG_TRANSPORT, "FREE", x, NULL, NULL, -1);
   if (x->recv_q) vQueueDelete(x->recv_q);
   if (x->send_q) vQueueDelete(x->send_q);
   if (x->accept_q) vQueueDelete(x->accept_q);
@@ -405,7 +572,7 @@ int mg_bsd_transport_listen(void *t, const struct sockaddr_in *addr) {
   int result = -1;
   struct mg_bsd_cmd cmd = {BSD_CMD_LISTEN, x, {0}, xTaskGetCurrentTaskHandle(), &result};
   snprintf(cmd.url, sizeof(cmd.url), "tcp://0.0.0.0:%d", mg_ntohs(addr->sin_port));
-  xQueueSend(s_cmd_q, &cmd, portMAX_DELAY);
+  if (!bsd_qsend(s_cmd_q, &cmd, portMAX_DELAY, false)) return -1;
   ulTaskNotifyTake(pdTRUE, portMAX_DELAY);
   return result;
 }
@@ -414,28 +581,50 @@ void *mg_bsd_transport_accept(void *t, struct sockaddr_in *peer, bool nonblock)
   struct mg_xport *x = (struct mg_xport *) t;
   struct mg_xport *nx = NULL;
   TickType_t ticks = nonblock ? 0 : portMAX_DELAY;
-  if (xQueueReceive(x->accept_q, &nx, ticks) != pdTRUE || !nx) return NULL;
+  if (xQueueReceive(x->accept_q, &nx, ticks) != pdTRUE) {
+    errno = x->closed ? (x->err ? x->err : EIO) : (nonblock ? EAGAIN : EIO);
+    return NULL;
+  }
+  if (!nx) { errno = x->err ? x->err : EIO; return NULL; }
   if (peer) *peer = nx->peer;
   return nx;
 }
 
 ssize_t mg_bsd_transport_recv(void *t, void *buf, size_t len, bool nonblock) {
   struct mg_xport *x = (struct mg_xport *) t;
-  struct mg_bsd_chunk chunk;
+  uint8_t *p = (uint8_t *) buf;
+  size_t recvd = 0;
   TickType_t ticks = nonblock ? 0 : portMAX_DELAY;
-  if (xQueueReceive(x->recv_q, &chunk, ticks) != pdTRUE) {
-    errno = EAGAIN;
-    return -1;
+  while (recvd < len) {
+    struct mg_bsd_chunk chunk;
+    if (xQueuePeek(x->recv_q, &chunk, recvd == 0 ? ticks : 0) != pdTRUE) {
+      if (recvd > 0) break;
+      errno = x->closed ? (x->err ? x->err : EIO) : (nonblock ? EAGAIN : EIO);
+      return -1;
+    }
+    if (chunk.len == 0) {
+      if (recvd > 0) break;
+      xQueueReceive(x->recv_q, &chunk, 0);
+      if (x->err) { errno = x->err; return -1; }
+      return 0;  // EOF
+    } else {
+      size_t n = chunk.len - x->rx_off;
+      if (n > len - recvd) n = len - recvd;
+      memcpy(p + recvd, chunk.data + x->rx_off, n);
+      recvd += n;
+      x->rx_off = (uint16_t) (x->rx_off + n);
+      if (x->rx_off >= chunk.len) {
+        xQueueReceive(x->recv_q, &chunk, 0);
+        x->rx_off = 0;
+      }
+    }
   }
-  if (chunk.len == 0) return 0;  // EOF
-  size_t n = chunk.len < len ? chunk.len : len;
-  memcpy(buf, chunk.data, n);
-  return (ssize_t) n;
+  return (ssize_t) recvd;
 }
 
 ssize_t mg_bsd_transport_send(void *t, const void *buf, size_t len, bool nonblock) {
   struct mg_xport *x = (struct mg_xport *) t;
-  if (x->closed) return -1;
+  if (x->closed) { errno = x->err ? x->err : EPIPE; return -1; }
   size_t sent = 0;
   TickType_t ticks = nonblock ? 0 : portMAX_DELAY;
   while (sent < len) {
@@ -444,7 +633,10 @@ ssize_t mg_bsd_transport_send(void *t, const void *buf, size_t len, bool nonbloc
     if (n > MG_BSD_CHUNK_SIZE) n = MG_BSD_CHUNK_SIZE;
     memcpy(chunk.data, (const uint8_t *) buf + sent, n);
     chunk.len = (uint16_t) n;
-    if (xQueueSend(x->send_q, &chunk, ticks) != pdTRUE) break;
+    if (!bsd_qsend(x->send_q, &chunk, ticks, false)) {
+      errno = x->closed ? (x->err ? x->err : EPIPE) : (nonblock ? EAGAIN : EIO);
+      return sent > 0 ? (ssize_t) sent : -1;
+    }
     sent += n;
   }
   return sent > 0 ? (ssize_t) sent : (errno = EAGAIN, -1);
@@ -453,7 +645,7 @@ ssize_t mg_bsd_transport_send(void *t, const void *buf, size_t len, bool nonbloc
 int mg_bsd_transport_connect(void *t, const struct sockaddr_in *addr, bool nonblock) {
   struct mg_xport *x = (struct mg_xport *) t;
   (void) nonblock;
-  if (!x->recv_q) x->recv_q = xQueueCreate(MG_BSD_Q_DEPTH, sizeof(struct mg_bsd_chunk));
+  if (!x->recv_q) x->recv_q = xQueueCreate(MG_BSD_Q_DEPTH + 1, sizeof(struct mg_bsd_chunk));
   if (!x->send_q) x->send_q = xQueueCreate(MG_BSD_Q_DEPTH, sizeof(struct mg_bsd_chunk));
   if (!x->recv_q || !x->send_q) { errno = ENOMEM; return -1; }
   int result = -1;
@@ -461,22 +653,18 @@ int mg_bsd_transport_connect(void *t, const struct sockaddr_in *addr, bool nonbl
   uint8_t *ip = (uint8_t *) &addr->sin_addr.s_addr;
   snprintf(cmd.url, sizeof(cmd.url), "tcp://%d.%d.%d.%d:%d",
            ip[0], ip[1], ip[2], ip[3], mg_ntohs(addr->sin_port));
-  xQueueSend(s_cmd_q, &cmd, portMAX_DELAY);
+  bsd_log(MG_BSD_LOG_CONNECT, "REQ", x, NULL, cmd.url, -1);
+  if (!bsd_qsend(s_cmd_q, &cmd, portMAX_DELAY, false)) return -1;
   ulTaskNotifyTake(pdTRUE, portMAX_DELAY);
+  if (result != 0) errno = x->err ? x->err : EIO;
   return result;
 }
 
 // gethostbyname: resolve via Mongoose DNS (not reentrant)
-static struct hostent s_hostent;
-static char *s_h_aliases[1];
-static char *s_h_addr_list[2];
-static uint32_t s_h_addr;
-static char s_h_name[64];
-
 struct hostent *gethostbyname(const char *name) {
   struct mg_bsd_cmd cmd = {BSD_CMD_RESOLVE, NULL, {0}, xTaskGetCurrentTaskHandle(), NULL};
   snprintf(cmd.url, sizeof(cmd.url), "%s", name);
-  xQueueSend(s_cmd_q, &cmd, portMAX_DELAY);
+  if (!bsd_qsend(s_cmd_q, &cmd, portMAX_DELAY, false)) return NULL;
   ulTaskNotifyTake(pdTRUE, portMAX_DELAY);
   if (s_resolve.error) return NULL;
   s_h_addr = s_resolve.addr.addr.ip4;
@@ -521,12 +709,18 @@ void freeaddrinfo(struct addrinfo *res) {
 
 void mg_bsd_transport_close(void *t) {
   struct mg_xport *x = (struct mg_xport *) t;
+  bsd_log(MG_BSD_LOG_TRANSPORT, "CLOSE", x, NULL, NULL, -1);
   if (!x->closed && x->c) {
     int result = 0;
     struct mg_bsd_cmd cmd = {BSD_CMD_CLOSE, x, {0}, xTaskGetCurrentTaskHandle(), &result};
-    xQueueSend(s_cmd_q, &cmd, portMAX_DELAY);
-    ulTaskNotifyTake(pdTRUE, portMAX_DELAY);
+    bool ok = bsd_qsend(s_cmd_q, &cmd, portMAX_DELAY, false);
+    bsd_log(MG_BSD_LOG_TRANSPORT, "CMD>", x, NULL, NULL, ok ? 1 : 0);
+    if (ok) {
+      ulTaskNotifyTake(pdTRUE, portMAX_DELAY);
+      bsd_log(MG_BSD_LOG_RESULT, "CMD", x, NULL, NULL, (long) result);
+    }
   }
+  bsd_log(MG_BSD_LOG_TRANSPORT, "FREE_REQ", x, NULL, NULL, -1);
   mg_bsd_transport_free(x);
 }
 
@@ -599,9 +793,8 @@ bool mg_wakeup(struct mg_mgr *mgr, unsigned long conn_id, const void *buf,
   m->id = conn_id;
   m->len = len;
   memcpy(m->data, buf, len);
-  if (xQueueSend((QueueHandle_t) mgr->pipe.q, &m, 0) != pdTRUE) {
+  if (!bsd_qsend((QueueHandle_t) mgr->pipe.q, &m, 0, false)) {
     free(m);
-    MG_ERROR(("xQueueSend"));
     return false;
   }
   return true;

src/dash.c

@@ -167,9 +167,11 @@ static size_t mg_dash_print_endpoint(mg_pfn_t fn, void *arg, va_list *ap) {
 void mg_dash_send_change(struct mg_mgr *mgr, struct mg_field_set *set) {
   struct mg_connection *c;
   for (c = mgr->conns; c != NULL; c = c->next) {
-    struct mg_dash_cdata *d = (struct mg_dash_cdata *) c->data;
-    struct mg_dash_user *u = d->u;
+    struct mg_dash_cdata *d;
+    struct mg_dash_user *u;
     if (!c->is_websocket) continue;
+    d = (struct mg_dash_cdata *) c->data;
+    u = d->u;
     if (u == NULL) continue;
     if (set->index != NULL && *set->index < 0) {
       int sz = mg_dash_array_size(set, u);

src/dns.c

@@ -228,16 +228,16 @@ static void dns_cb(struct mg_connection *c, int ev, void *ev_data) {
   }
 }
 
-static bool mg_dns_send(struct mg_connection *c, const struct mg_str *name,
-                        uint16_t txnid, bool ipv6) {
-  struct {
+static bool dns_send(struct mg_connection *c, const struct mg_str *name,
+                     unsigned int rtype, uint16_t txnid, uint16_t flags) {
+  struct { // RFC-1035 4.1.2
     struct mg_dns_header header;
     uint8_t data[256];
   } pkt;
   size_t i, n;
   memset(&pkt, 0, sizeof(pkt));
   pkt.header.txnid = mg_htons(txnid);
-  pkt.header.flags = mg_htons(0x100);
+  pkt.header.flags = mg_htons(flags);
   pkt.header.num_questions = mg_htons(1);
   for (i = n = 0; i < sizeof(pkt.data) - 5; i++) {
     if (name->buf[i] == '.' || i >= name->len) {
@@ -247,14 +247,19 @@ static bool mg_dns_send(struct mg_connection *c, const struct mg_str *name,
     }
     if (i >= name->len) break;
   }
-  memcpy(&pkt.data[n], "\x00\x00\x01\x00\x01", 5);  // A query
+  memset(&pkt.data[n], 0, 5);         // nul, QTYPE, QCLASS
+  pkt.data[n + 2] = (uint8_t) rtype;  // QTYPE = rtype, only 0-255 supported
+  pkt.data[n + 4] = 1;                // QCLASS = IN
   n += 5;
-  if (ipv6) pkt.data[n - 3] = 0x1c;  // AAAA query
-  // memcpy(&pkt.data[n], "\xc0\x0c\x00\x1c\x00\x01", 6);  // AAAA query
-  // n += 6;
   return mg_send(c, &pkt, sizeof(pkt.header) + n);
 }
 
+static bool mg_dns_send(struct mg_connection *c, const struct mg_str *name,
+                        uint16_t txnid, bool ipv6) {
+  return dns_send(c, name, ipv6 ? MG_DNS_RTYPE_AAAA : MG_DNS_RTYPE_A, txnid,
+                  0x100); // RD
+}
+
 bool mg_dnsc_init(struct mg_mgr *mgr, struct mg_dns *dnsc);
 bool mg_dnsc_init(struct mg_mgr *mgr, struct mg_dns *dnsc) {
   if (dnsc->url == NULL) {
@@ -458,7 +463,6 @@ static void handle_mdns_query(struct mg_connection *c) {
     MG_VERBOSE(("RR %u %u %s", (unsigned int) rr.atype,
                 (unsigned int) rr.aclass, name));
     if (rr.atype == MG_DNS_RTYPE_A) {
-      // TODO(): ensure c->fn_data ends in \0
       // if we have a name to match, go; otherwise users will match and fill
       // req.r.name and set req.is_resp
       if (c->fn_data != NULL && mg_casecmp((char *) c->fn_data, name) != 0)
@@ -574,43 +578,149 @@ static void handle_mdns_query(struct mg_connection *c) {
   }
 }
 
+
+static size_t srvtoname(char *svc) {
+  char *dot = strchr(svc, '.');
+  if (dot == NULL) return 0;
+  *dot = '\0';
+  return (size_t) (dot - svc);
+}
+
+#define MG_MAX_MDNS_RECORDS 8
+// Condense one useful mDNS/DNS-SD chain from a response datagram into a single
+// MG_EV_MDNS_RESP event. A/AAAA as the first supported record are terminal
+// address answers (AAAA currently ignored). For PTR/SRV/TXT, subsequent
+// records are attached only when their label matches the service instance, or
+// the SRV target for address records.
+// Some devices send SRV/TXT as extra Answer RRs instead of Additional RRs, so
+// both sections are parsed as one chain.
 static void handle_mdns_response(struct mg_connection *c) {
   struct mg_dns_header *rh = (struct mg_dns_header *) c->recv.buf;
-  struct mg_dns_rr rr;
-  size_t n;
-  // Parse first response, offset 12 is header size
-  n = mg_dns_parse_rr(c->recv.buf, c->recv.len, 12, false, &rr);
-  MG_VERBOSE(("mDNS response parsed, result=%d", (int) n));
-  if (n > 0) {
-    // RFC-6762 Appendix C, RFC2181 11: m(n + 1-63), max 255 + 0x0
-    char name[256];
-    uint8_t name_len;
-    struct mg_mdns_resp resp;
-    memset(&resp, 0, sizeof(resp));
-    if (rh->num_answers > mg_htons(1)) MG_DEBUG(("ignoring > 1 answers"));
-    mg_dns_parse_name(c->recv.buf, c->recv.len, 12, name, sizeof(name));
-    name_len = (uint8_t) strlen(name);
-    MG_VERBOSE(("RR %u %u %s", (unsigned int) rr.atype,
-                (unsigned int) rr.aclass, name));
-    if (rr.alen == 4 && rr.atype == MG_DNS_RTYPE_A &&
-        (rr.aclass & 0x7FFF) == 1) {
-      resp.addr.is_ip6 = false;
-      memcpy(resp.addr.addr.ip, (char *) (rh + 1) + n - 4, 4);
-      MG_DEBUG(("A response from %.*s = %M", name_len, name, mg_print_ip,
-                &resp.addr));
-      //    } else if (rr.alen == 16 && rr.atype == MG_DNS_RTYPE_AAAA &&
-      //    (rr.aclass & 0x7FFF) == 1) {
-      //      resp.addr.is_ip6 = true;
-      //      memcpy(resp.addr.addr.ip, (char *)(rh + 1) + n - 16], 16);
-      //      MG_DEBUG(("AAAA response from %.*s = %M", name_len, name,
-      //      mg_print_ip, &resp.addr));
-    } else {
-      return;
-    }
-    resp.name = mg_str_n(name, name_len);
-    resp.rr = &rr;
-    mg_call(c, MG_EV_MDNS_RESP, &resp);
+  struct mg_dns_rr rr, rr_[5]; // A, PTR, SRV, TXT, AAAA, in that order
+  struct mg_mdns_resp resp;
+  size_t n, i, num, answers, roff_[5], roff = 12;  // offset 12 is header size
+  // RFC-6762 Appendix C, RFC2181 11: m(n + 1-63), max 255 + 0x0
+  char name[256], srvcproto[256], instance[256], host[256];
+  uint16_t atype = 0;
+  answers = mg_ntohs(rh->num_answers);
+  num = answers + mg_ntohs(rh->num_other_prs);
+  if (answers == 0) return;
+  MG_VERBOSE(("mDNS response: %u answer, %u additional", (unsigned) answers,
+              (unsigned) (num - answers)));
+  if (num > MG_MAX_MDNS_RECORDS) {
+    num = MG_MAX_MDNS_RECORDS;
+    MG_DEBUG(("ignoring > %u records", MG_MAX_MDNS_RECORDS));
   }
+  memset(roff_, 0, sizeof(roff_));
+  memset(&rr_, 0, sizeof(rr_));
+  memset(&resp, 0, sizeof(resp));
+  instance[0] = host[0] = '\0';
+  for (i = 0; i < num; i++) { // First Answer RR is primary; the rest must match it
+    n = mg_dns_parse_rr(c->recv.buf, c->recv.len, roff, false, &rr);
+    MG_VERBOSE(("mDNS record parsed, result=%u", n));
+    if (n == 0) return;
+    if (mg_dns_parse_name(c->recv.buf, c->recv.len, roff, name, sizeof(name)) == 0) return;
+    MG_VERBOSE(("RR %u %u %s", (unsigned int) rr.atype, (unsigned int) rr.aclass, name));
+    if (rr.alen == 4 && rr.atype == MG_DNS_RTYPE_A && (rr.aclass & 0x7FFF) == 1 &&
+        (i == 0 || (host[0] != '\0' && strcmp(name, host) == 0) ||
+         (host[0] == '\0' && instance[0] != '\0' && strcmp(name, instance) == 0))) {
+      if (rr_[0].atype != 0) break;
+      if (i == 0) atype = rr.atype;
+      resp.name = mg_str(name);
+      resp.addr.is_ip6 = false;
+      memcpy(resp.addr.addr.ip, c->recv.buf + roff + n - 4, 4);
+      MG_VERBOSE(("A record"));
+      roff_[0] = roff, rr_[0] = rr;
+      if (atype == MG_DNS_RTYPE_A) break;
+    } else if (rr.alen == 16 && rr.atype == MG_DNS_RTYPE_AAAA && (rr.aclass & 0x7FFF) == 1 &&
+               (i == 0 || (host[0] != '\0' && strcmp(name, host) == 0) ||
+                (host[0] == '\0' && instance[0] != '\0' && strcmp(name, instance) == 0))) {
+# if 0
+      if (rr_[4].atype != 0) break;
+      resp.addr.is_ip6 = true;
+      if (i == 0) atype = rr.atype;
+      resp.name = mg_str(name);
+      memcpy(resp.addr.addr.ip, c->recv.buf + roff + n - 16, 16);
+      MG_VERBOSE(("AAAA record"));
+      roff_[4] = roff, rr_[4] = rr;
+      if (atype == MG_DNS_RTYPE_AAAA) break;
+#else
+      MG_VERBOSE(("ignored AAAA record"));
+#endif
+    } else if (rr.atype == MG_DNS_RTYPE_PTR && (rr.aclass & 0x7FFF) == 1 && i == 0) {
+      if (rr_[1].atype != 0) break;
+      atype = rr.atype;
+      if (mg_dns_parse_name(c->recv.buf, c->recv.len, roff + rr.nlen + 10,
+                            instance, sizeof(instance)) == 0) return;
+      MG_VERBOSE(("PTR record"));
+      roff_[1] = roff, rr_[1] = rr;
+    } else if (rr.atype == MG_DNS_RTYPE_SRV && rr.alen >= 6 && (rr.aclass & 0x7FFF) == 1 &&
+               (i == 0 || (instance[0] != '\0' && strcmp(name, instance) == 0))) {
+      if (rr_[2].atype != 0) break;
+      if (i == 0) atype = rr.atype;
+      resp.sd.port = MG_LOAD_BE16(c->recv.buf + roff + rr.nlen + 14);
+      resp.addr.port = mg_htons(resp.sd.port);
+      if (instance[0] == '\0') mg_snprintf(instance, sizeof(instance), "%s", name);
+      if (mg_dns_parse_name(c->recv.buf, c->recv.len, roff + rr.nlen + 16,
+                            host, sizeof(host)) == 0) return;
+      MG_VERBOSE(("SRV record"));
+      roff_[2] = roff, rr_[2] = rr;
+    } else if (rr.atype == MG_DNS_RTYPE_TXT && (rr.aclass & 0x7FFF) == 1 &&
+               (i == 0 || (instance[0] != '\0' && strcmp(name, instance) == 0))) {
+      if (rr_[3].atype != 0) break;
+      if (i == 0) atype = rr.atype;
+      if (instance[0] == '\0') mg_snprintf(instance, sizeof(instance), "%s", name);
+      resp.sd.txt = mg_str_n((char *) c->recv.buf + roff + rr.nlen + 10, rr.alen);
+      MG_VERBOSE(("TXT record"));
+      roff_[3] = roff, rr_[3] = rr;
+    }
+    roff += n;
+    if (i == 0 && atype == 0) return;
+  }
+  if (atype == MG_DNS_RTYPE_A) {
+    resp.rr = &rr_[0];
+    MG_DEBUG(("A response from %s = %M", name, mg_print_ip, &resp.addr));
+#if 0
+  } else if (atype == MG_DNS_RTYPE_AAAA) {
+    resp.rr = &rr_[4];
+    MG_DEBUG(("AAAA response from %s = %M", name, mg_print_ip6, resp.addr.addr.ip));
+#endif
+  } else if (atype == MG_DNS_RTYPE_PTR) {
+    size_t len;
+    resp.rr = &rr_[1];
+    if (mg_dns_parse_name(c->recv.buf, c->recv.len, roff_[1], srvcproto,
+                          sizeof(srvcproto)) == 0) return;
+    len = strlen(srvcproto);
+    if (len <= 6) return;
+    resp.sd.srvcproto = mg_str_n(srvcproto, len - 6);  // remove .local
+    if (host[0] != '\0') {
+      resp.name = mg_str(host);
+    } else if (rr_[0].atype == 0) {
+      mg_snprintf(name, sizeof(name), "%s", instance);
+      resp.name = mg_str_n(name, srvtoname(name));
+    } else {
+      if (mg_dns_parse_name(c->recv.buf, c->recv.len, roff_[0], name,
+                            sizeof(name)) == 0) return;
+      resp.name = mg_str(name);
+    }
+    MG_DEBUG(("PTR response for %s from %s", srvcproto, name));
+  } else if (atype == MG_DNS_RTYPE_SRV || atype == MG_DNS_RTYPE_TXT) {
+    size_t len, name_len;
+    resp.rr = atype == MG_DNS_RTYPE_SRV ? &rr_[2] : &rr_[3];
+    if (mg_dns_parse_name(c->recv.buf, c->recv.len,
+                          atype == MG_DNS_RTYPE_SRV ? roff_[2] : roff_[3],
+                          srvcproto, sizeof(srvcproto)) == 0)
+      return;
+    len = strlen(srvcproto);
+    name_len = srvtoname(srvcproto);
+    if (name_len == 0 || len <= name_len + 7) return;  // remove .local
+    resp.sd.srvcproto = mg_str_n(srvcproto + name_len + 1, len - name_len - 7);
+    resp.name = mg_str_n(srvcproto, name_len);
+    MG_DEBUG(("%s response for %s from %s", atype == MG_DNS_RTYPE_SRV ? "SRV" : "TXT", srvcproto, name));
+  } else {
+    return;
+  }
+  mg_call(c, MG_EV_MDNS_RESP, &resp);
 }
 
 static void handle_mdns_record(struct mg_connection *c) {
@@ -684,8 +794,7 @@ struct mg_connection *mg_mdns_listen(struct mg_mgr *mgr, mg_event_handler_t fn,
 static bool mdns_query(struct mg_connection *c, struct mg_str *name,
                        unsigned int rtype) {
   mg_multicast_restore(c, (uint8_t *) &c->loc);
-  (void) rtype;
-  return mg_dns_send(c, name, 0, false);
+  return dns_send(c, name, rtype, 0, 0);  // RFC-6762 18.1 id = 0, 18.6 RD = 0
 }
 
 bool mg_mdns_query(struct mg_connection *c, const char *name,

src/dns.h

@@ -60,11 +60,12 @@ struct mg_mdns_req {
   bool is_unicast;  // True if the client requested a unicast (QU) response
 };
 
-// ev_data for MG_EV_MDNS_RESP, carrying the resolved address from an mDNS response.
+// ev_data for MG_EV_MDNS_RESP, carrying address/data from a mDNS response
 struct mg_mdns_resp {
-  struct mg_dns_rr *rr;  // Resource record from the response
+  struct mg_dns_rr *rr;  // Resource record from the response (1st in chain)
   struct mg_str name;    // Resolved hostname, without the .local suffix
   struct mg_addr addr;   // Resolved IP address
+  struct mg_dnssd_record sd; // Service Discovery data
 };
 
 // Parses a DNS query or response from buf/len into dm. Returns true on success.
@@ -81,6 +82,7 @@ size_t mg_dns_parse_rr(const uint8_t *buf, size_t len, size_t ofs,
 // Creates an mDNS listener on UDP multicast 224.0.0.251:5353. Registers it as
 // the manager's mDNS resolver (mgr->mdns). Fires MG_EV_MDNS_REQ for incoming
 // queries and MG_EV_MDNS_RESP for incoming responses. Returns NULL on error.
+// fn_data is a NUL-terminated server name, or NULL to pass all requests to fn.
 struct mg_connection *mg_mdns_listen(struct mg_mgr *mgr, mg_event_handler_t fn,
                                      void *fn_data);
 

src/drivers/at_cmd.c

@@ -9,7 +9,9 @@
 
 static size_t print_atcmd(void (*out)(char, void *), void *arg, va_list *ap) {
   struct mg_str s = va_arg(*ap, struct mg_str);
-  for (size_t i = 0; i < s.len; i++) out(s.buf[i] < 0x20 ? '.' : s.buf[i], arg);
+  size_t i;
+  for (i = 0; i < s.len; i++)
+    out((char) (s.buf[i] < 0x20 ? '.' : s.buf[i]), arg);
   return s.len;
 }
 
@@ -27,7 +29,7 @@ static bool mg_atcmd_handle(struct mg_tcpip_if *ifp) {
     if (dd->script_index % 2 == 0) {  // send AT command
       const char *cmd = dd->script[dd->script_index];
       MG_DEBUG(("send AT[%d]: %M", dd->script_index, print_atcmd, mg_str(cmd)));
-      while (*cmd) dd->tx(dd->usart, *cmd++);
+      while (*cmd != '\0') dd->tx(dd->usart, (uint8_t) *cmd++);
       dd->script_index++;
       ifp->recv_queue.head = 0;
     } else {  // check AT command response
@@ -43,7 +45,7 @@ static bool mg_atcmd_handle(struct mg_tcpip_if *ifp) {
           return false;  // FAIL
         }
         if ((c = dd->rx(dd->usart)) < 0) return false;  // no data
-        q->buf[q->head++] = c;
+        q->buf[q->head++] = (char) c;
         if (mg_match(mg_str_n(q->buf, q->head), mg_str(expect), NULL)) {
           MG_DEBUG(("recv AT[%d]: %M", dd->script_index, print_atcmd,
                     mg_str_n(q->buf, q->head)));
@@ -84,7 +86,7 @@ static size_t mg_atcmd_rx(void *buf, size_t len, struct mg_tcpip_if *ifp) {
       }
     }
     if (!dd->no_byte_stuff && !byte_unstuff(dd, &b)) continue;
-    q->buf[q->head++] = b;
+    q->buf[q->head++] = (char) b;
   }
   len = (q->head <= len) ? q->head : 0;
   memmove(buf, q->buf, len);
@@ -130,7 +132,7 @@ struct mg_tcpip_driver mg_tcpip_driver_atcmd = {mg_atcmd_init, mg_atcmd_tx, mg_a
 static void byte_stuff(struct mg_tcpip_driver_atcmd_data *dd, uint8_t b) {
   if ((b < 0x20) || (b == MG_HDLC_ESC) || (b == MG_HDLC_FLAG)) {
     dd->tx(dd->usart, MG_HDLC_ESC);
-    dd->tx(dd->usart, b ^ 0x20);
+    dd->tx(dd->usart, (uint8_t) (b ^ 0x20));
   } else {
     dd->tx(dd->usart, b);
   }

src/flash.c

@@ -37,6 +37,9 @@ bool mg_ota_flash_write(const void *buf, size_t len, struct mg_flash *flash) {
   bool ok = false;
   if (s_size == 0) {
     MG_ERROR(("OTA is not started, call mg_ota_begin()"));
+  } else if (s_addr + MG_ROUND_UP(len, flash->align) >
+             (char *) flash->start + flash->size) {
+    MG_ERROR(("Flash overflow: attempting to write past the flash boundary"));
   } else {
     size_t len_aligned_down = MG_ROUND_DOWN(len, flash->align);
     if (len_aligned_down) ok = flash->write_fn(s_addr, buf, len_aligned_down);

src/fmt.c

@@ -173,6 +173,7 @@ size_t mg_vxprintf(void (*out)(char, void *), void *param, const char *fmt,
         is_long++, c = fmt[++i];
         if (c == 'l') is_long++, c = fmt[++i];
       }
+      if (c == 'z') is_long = 1, c = fmt[++i];
       if (c == 'p') x = 1, is_long = 1;
       if (c == 'd' || c == 'u' || c == 'x' || c == 'X' || c == 'p' ||
           c == 'g' || c == 'f') {

src/fs_fat.c

@@ -1,44 +1,19 @@
 #include "arch.h"
 #include "event.h"
 #include "fs.h"
+#include "util.h"
 
 #if MG_ENABLE_FATFS
 #include <ff.h>
 
-static int mg_days_from_epoch(int y, int m, int d) {
-  y -= m <= 2;
-  int era = y / 400;
-  int yoe = y - era * 400;
-  int doy = (153 * (m + (m > 2 ? -3 : 9)) + 2) / 5 + d - 1;
-  int doe = yoe * 365 + yoe / 4 - yoe / 100 + doy;
-  return era * 146097 + doe - 719468;
-}
-
-static time_t mg_timegm(const struct tm *t) {
-  int year = t->tm_year + 1900;
-  int month = t->tm_mon;  // 0-11
-  if (month > 11) {
-    year += month / 12;
-    month %= 12;
-  } else if (month < 0) {
-    int years_diff = (11 - month) / 12;
-    year -= years_diff;
-    month += 12 * years_diff;
-  }
-  int x = mg_days_from_epoch(year, month + 1, t->tm_mday);
-  return 60 * (60 * (24L * x + t->tm_hour) + t->tm_min) + t->tm_sec;
-}
-
 static time_t ff_time_to_epoch(uint16_t fdate, uint16_t ftime) {
-  struct tm tm;
-  memset(&tm, 0, sizeof(struct tm));
-  tm.tm_sec = (ftime << 1) & 0x3e;
-  tm.tm_min = ((ftime >> 5) & 0x3f);
-  tm.tm_hour = ((ftime >> 11) & 0x1f);
-  tm.tm_mday = (fdate & 0x1f);
-  tm.tm_mon = ((fdate >> 5) & 0x0f) - 1;
-  tm.tm_year = ((fdate >> 9) & 0x7f) + 80;
-  return mg_timegm(&tm);
+  unsigned int sec = (ftime << 1) & 0x3e;
+  unsigned int min = (ftime >> 5) & 0x3f;
+  unsigned int hour = (ftime >> 11) & 0x1f;
+  unsigned int day = fdate & 0x1f;
+  unsigned int month = (fdate >> 5) & 0x0f;
+  unsigned int year = ((fdate >> 9) & 0x7f) + 1980;
+  return (time_t) mg_timegm(year, month, day, hour, min, sec);
 }
 
 static int ff_stat(const char *path, size_t *size, time_t *mtime) {

src/http.c

@@ -1030,7 +1030,7 @@ static void mg_upload_handler(struct mg_connection *c, int ev, void *ev_data) {
     size_t alignment = 512;
     size_t left = p->expected > p->received ? p->expected - p->received : 0;
     size_t aligned = c->recv.len < left ? MG_ROUND_DOWN(c->recv.len, alignment)
-                                        : c->recv.len;
+                                        : left;
     bool ok = true;
     if (aligned > 0) {
       if (p->fd != NULL) {
@@ -1114,15 +1114,14 @@ static bool is_hex_digit(int c) {
 }
 
 static int skip_chunk(const char *buf, int len, int *pl, int *dl) {
-  int i = 0, n = 0;
+  int i = 0, n = 0;  // pass int to mg_str_to_num, treats as unsigned
   if (len < 3) return 0;
   while (i < len && is_hex_digit(buf[i])) i++;
-  if (i == 0) return -1;                     // Error, no length specified
-  if (i > (int) sizeof(int) * 2) return -1;  // Chunk length is too big
+  if (i == 0) return -1;  // Error, no length specified
   if (len < i + 2 || buf[i] != '\r' || buf[i + 1] != '\n') return -1;  // Error
-  if (mg_str_to_num(mg_str_n(buf, (size_t) i), 16, &n, sizeof(int)) == false)
+  if (mg_str_to_num(mg_str_n(buf, (size_t) i), 16, &n, sizeof(n)) == false)
     return -1;                    // Decode chunk length, overflow
-  if (n < 0) return -1;           // Error. TODO(): some checks now redundant
+  if (n < 0) return -1;           // Chunk length is too big <0 = >0x80000000
   if (n > len - i - 4) return 0;  // Chunk not yet fully buffered
   if (buf[i + n + 2] != '\r' || buf[i + n + 3] != '\n') return -1;  // Error
   *pl = i + 2, *dl = n;

src/json.c

@@ -363,15 +363,18 @@ char *mg_json_get_b64(struct mg_str json, const char *path, int *slen) {
 char *mg_json_get_hex(struct mg_str json, const char *path, int *slen) {
   char *result = NULL;
   int len = 0, off = mg_json_get(json, path, &len);
-  if (off >= 0 && json.buf[off] == '"' && len > 1 &&
+  if (off >= 0 && json.buf[off] == '"' && len > 1 && (len - 2) % 2 == 0 &&
       (result = (char *) mg_calloc(1, (size_t) len / 2)) != NULL) {
     int i;
     for (i = 0; i < len - 2; i += 2) {
-      mg_str_to_num(mg_str_n(json.buf + off + 1 + i, 2), 16, &result[i >> 1],
-                    sizeof(uint8_t));
+      if (!mg_str_to_num(mg_str_n(json.buf + off + 1 + i, 2), 16,
+                         &result[i >> 1], sizeof(uint8_t))) break;
+    }
+    if (i < len - 2) mg_free(result), result = NULL;
+    if (result != NULL) {
+      result[len / 2 - 1] = '\0';
+      if (slen != NULL) *slen = len / 2 - 1;
     }
-    result[len / 2 - 1] = '\0';
-    if (slen != NULL) *slen = len / 2 - 1;
   }
   return result;
 }

src/json.h

@@ -57,7 +57,7 @@ char *mg_json_get_str(struct mg_str json, const char *path);
 
 // Decodes a hex-encoded JSON string at path into a heap-allocated byte array.
 // Sets *len to the decoded byte count. Caller must mg_free() the result.
-// Returns NULL if not found or not a string.
+// Returns NULL if not found, not a string, or not valid hexadecimal.
 char *mg_json_get_hex(struct mg_str json, const char *path, int *len);
 
 // Decodes a base64-encoded JSON string at path into a heap-allocated byte

src/jwt.c

@@ -0,0 +1,164 @@
+#include "jwt.h"
+#include "base64.h"
+#include "json.h"
+#include "log.h"
+#include "printf.h"
+#include "sha256.h"
+#include "util.h"
+
+#if MG_TLS == MG_TLS_BUILTIN
+#include "tls_uecc.h"
+#endif
+
+static size_t jwt_split(struct mg_str jwt, struct mg_str *h, struct mg_str *p,
+                        struct mg_str *s) {
+  size_t i, a = jwt.len, b = jwt.len;
+  for (i = 0; i < jwt.len; i++) {
+    if (jwt.buf[i] == '.') {
+      if (a == jwt.len) a = i;
+      if (a != i) b = i;
+      if (b != jwt.len) break;
+    }
+  }
+  if (a == jwt.len || b == jwt.len || b + 1 >= jwt.len) return 0;
+  *h = mg_str_n(jwt.buf, a);
+  *p = mg_str_n(jwt.buf + a + 1, b - a - 1);
+  *s = mg_str_n(jwt.buf + b + 1, jwt.len - b - 1);
+  return b;
+}
+
+static bool jwt_alg(struct mg_str h, const char *alg) {
+  char got[16];
+  size_t len = h.len * 3 / 4 + 2;
+  char *buf = (char *) mg_calloc(1, len);
+  bool ok;
+  if (buf == NULL) return false;
+  ok = mg_base64url_decode(h.buf, h.len, buf, len) > 0 &&
+       mg_json_unescape(mg_str(buf), "$.alg", got, sizeof(got)) > 0 &&
+       strcmp(got, alg) == 0;
+  mg_free(buf);
+  return ok;
+}
+
+static size_t jwt_header_payload(const char *alg, const struct mg_jwt_opts *opts,
+                                 char *buf, size_t len) {
+  char *header, *kid = NULL;
+  size_t n, m;
+  if (opts->kid.len > 0) {
+    kid = mg_mprintf(",%m:%m", MG_ESC("kid"), mg_print_esc,
+                     (int) opts->kid.len, opts->kid.buf);
+    if (kid == NULL) return 0;
+  }
+  header = mg_mprintf("{%m:%m,%m:%m%.*s%.*s%.*s}", MG_ESC("alg"),
+                      MG_ESC(alg), MG_ESC("typ"), MG_ESC("JWT"),
+                      kid == NULL ? 0 : (int) strlen(kid),
+                      kid == NULL ? "" : kid,
+                      opts->header.len > 0 ? 1 : 0, ",",
+                      (int) opts->header.len, opts->header.buf);
+  mg_free(kid);
+  if (header == NULL) return 0;
+  n = mg_base64url_encode((uint8_t *) header, strlen(header), buf, len);
+  mg_free(header);
+  if (n == 0 || n + 1 >= len) return 0;
+  buf[n++] = '.';
+  m = mg_base64url_encode((uint8_t *) opts->claims.buf, opts->claims.len,
+                          buf + n, len - n);
+  return m == 0 ? 0 : n + m;
+}
+
+size_t mg_jwt_sign_hs256(const struct mg_jwt_opts *opts, char *buf,
+                         size_t len) {
+  uint8_t sig[32];
+  size_t n = jwt_header_payload("HS256", opts, buf, len);
+  size_t m;
+  if (n == 0 || n + 1 >= len) return 0;
+  mg_hmac_sha256(sig, (uint8_t *) opts->secret.buf, opts->secret.len,
+                 (uint8_t *) buf, n);
+  buf[n++] = '.';
+  m = mg_base64url_encode(sig, sizeof(sig), buf + n, len - n);
+  return m == 0 ? 0 : n + m;
+}
+
+size_t mg_jwt_verify_hs256(struct mg_str jwt, const struct mg_jwt_opts *opts,
+                           char *buf, size_t len) {
+  struct mg_str h, p, s;
+  uint8_t sig[33], digest[32];
+  size_t n = jwt_split(jwt, &h, &p, &s);
+  if (n == 0 || !jwt_alg(h, "HS256")) return 0;
+  if (mg_base64url_decode(s.buf, s.len, (char *) sig, sizeof(sig)) !=
+      sizeof(digest))
+    return 0;
+  mg_hmac_sha256(digest, (uint8_t *) opts->secret.buf, opts->secret.len,
+                 (uint8_t *) jwt.buf, n);
+  if (!mg_memeq(sig, digest, sizeof(digest))) return 0;
+  return mg_base64url_decode(p.buf, p.len, buf, len);
+}
+
+#if MG_TLS == MG_TLS_BUILTIN
+typedef struct {
+  MG_UECC_HashContext uECC;
+  mg_sha256_ctx sha256;
+} jwt_hash_ctx;
+
+static void jwt_hash_init(const MG_UECC_HashContext *ctx) {
+  jwt_hash_ctx *c = (jwt_hash_ctx *) ctx;
+  mg_sha256_init(&c->sha256);
+}
+
+static void jwt_hash_update(const MG_UECC_HashContext *ctx, const uint8_t *msg,
+                            unsigned len) {
+  jwt_hash_ctx *c = (jwt_hash_ctx *) ctx;
+  mg_sha256_update(&c->sha256, msg, len);
+}
+
+static void jwt_hash_finish(const MG_UECC_HashContext *ctx, uint8_t *hash) {
+  jwt_hash_ctx *c = (jwt_hash_ctx *) ctx;
+  mg_sha256_final(hash, &c->sha256);
+}
+
+size_t mg_jwt_sign_es256(const struct mg_jwt_opts *opts, char *buf,
+                         size_t len) {
+  uint8_t hash[32], sig[64], tmp[2 * 32 + 64];
+  jwt_hash_ctx ctx = {
+      {jwt_hash_init, jwt_hash_update, jwt_hash_finish, 64, 32, tmp},
+      {{0}, 0, 0, {0}}};
+  size_t n = jwt_header_payload("ES256", opts, buf, len);
+  size_t m;
+  if (n == 0 || n + 1 >= len) return 0;
+  mg_sha256(hash, (uint8_t *) buf, n);
+  if (mg_uecc_sign_deterministic(opts->private_key, hash, sizeof(hash),
+                                 &ctx.uECC, sig, mg_uecc_secp256r1()) != 1)
+    return 0;
+  buf[n++] = '.';
+  m = mg_base64url_encode(sig, sizeof(sig), buf + n, len - n);
+  return m == 0 ? 0 : n + m;
+}
+
+size_t mg_jwt_verify_es256(struct mg_str jwt, const struct mg_jwt_opts *opts,
+                           char *buf, size_t len) {
+  struct mg_str h, p, s;
+  uint8_t sig[65], hash[32];
+  size_t n = jwt_split(jwt, &h, &p, &s);
+  if (n == 0 || !jwt_alg(h, "ES256")) return 0;
+  if (mg_base64url_decode(s.buf, s.len, (char *) sig, sizeof(sig)) != 64)
+    return 0;
+  mg_sha256(hash, (uint8_t *) jwt.buf, n);
+  if (mg_uecc_verify(opts->public_key, hash, sizeof(hash), sig,
+                     mg_uecc_secp256r1()) != 1)
+    return 0;
+  return mg_base64url_decode(p.buf, p.len, buf, len);
+}
+#else
+size_t mg_jwt_sign_es256(const struct mg_jwt_opts *opts, char *buf,
+                         size_t len) {
+  (void) opts, (void) buf, (void) len;
+  MG_ERROR(("JWT ES256 requires built-in TLS"));
+  return 0;
+}
+
+size_t mg_jwt_verify_es256(struct mg_str jwt, const struct mg_jwt_opts *opts,
+                           char *buf, size_t len) {
+  (void) jwt, (void) opts, (void) buf, (void) len;
+  return mg_jwt_sign_es256(NULL, NULL, 0);
+}
+#endif

src/jwt.h

@@ -0,0 +1,27 @@
+#pragma once
+
+#include "arch.h"
+#include "str.h"
+#include "tls.h"
+
+struct mg_jwt_opts {
+  struct mg_str claims;  // JSON payload
+  struct mg_str header;  // Extra header members, no braces; alg/typ are set
+  struct mg_str kid;     // Key ID protected header
+  struct mg_str secret;  // HS256 secret
+  const uint8_t *private_key;  // ES256 private key (MG_TLS_BUILTIN only)
+  const uint8_t *public_key;   // ES256 public key (MG_TLS_BUILTIN only)
+};
+
+// Signs JSON claims as a compact JWT. Returns JWT length, or 0 on error.
+size_t mg_jwt_sign_hs256(const struct mg_jwt_opts *opts, char *buf,
+                         size_t len);
+
+// Verifies JWT and decodes JSON claims into buf. Returns claims length, or 0.
+size_t mg_jwt_verify_hs256(struct mg_str jwt, const struct mg_jwt_opts *opts,
+                           char *buf, size_t len);
+
+size_t mg_jwt_sign_es256(const struct mg_jwt_opts *opts, char *buf,
+                         size_t len);
+size_t mg_jwt_verify_es256(struct mg_str jwt, const struct mg_jwt_opts *opts,
+                           char *buf, size_t len);

src/l2.h

@@ -6,7 +6,7 @@
 #if MG_ENABLE_TCPIP
 
 // no config defaults to 0 => Ethernet
-enum mg_l2type { MG_TCPIP_L2_ETH = 0, MG_TCPIP_L2_PPP, MG_TCPIP_L2_PPPoE };
+enum mg_l2type { MG_TCPIP_L2_ETH = 0, MG_TCPIP_L2_PPP, MG_TCPIP_L2_PPPoE, MG_TCPIP_L2_USER };
 
 #if defined(__DCC__)
 #pragma pack(1)

src/l2_eth.c

@@ -94,6 +94,13 @@ size_t mg_l2_eth_trailer(struct mg_tcpip_if *ifp, size_t len, uint8_t *cur) {
 struct mg_l2addr *mg_l2_eth_mapip(enum mg_l2addrtype addrtype,
                                   struct mg_addr *addr);
 
+// Read an unaligned little-endian value from byte pointer p into a native integer.
+// Safe on architectures that forbid unaligned access (e.g. Cortex-M0).
+#define MG_LOAD_LE32(p)                           \
+  ((uint32_t) (((uint32_t) MG_U8P(p)[3] << 24U) | \
+               ((uint32_t) MG_U8P(p)[2] << 16U) | \
+               ((uint32_t) MG_U8P(p)[1] << 8U) | MG_U8P(p)[0]))
+
 bool mg_l2_eth_rx(struct mg_tcpip_if *ifp, enum mg_l2proto *proto,
                   struct mg_str *pay, struct mg_str *raw) {
   struct eth *eth = (struct eth *) raw->buf;
@@ -109,7 +116,7 @@ bool mg_l2_eth_rx(struct mg_tcpip_if *ifp, enum mg_l2proto *proto,
   } else {  // We do, check 802.1Q tag
     struct qtag *qtag = (struct qtag *) &eth->type;
     if (qtag->tpid != mg_htons(0x8100)) return false;  // Untagged frame
-    if (mg_ntohs(VLAN_ID(qtag->tci)) != VLAN_ID(d->vlan_id))
+    if (VLAN_ID(mg_ntohs(qtag->tci)) != VLAN_ID(d->vlan_id))
       return false;  // Not our VLAN
     type = MG_LOAD_BE16(qtag + 1);
   }
@@ -119,10 +126,11 @@ bool mg_l2_eth_rx(struct mg_tcpip_if *ifp, enum mg_l2proto *proto,
              sizeof(eth->dst)) != 0)
     return false;  // TODO(): add multicast addresses
   if (ifp->enable_fcs_check && len > hdrlen + 4) {
-    uint32_t crc;
-    len -= 4;  // TODO(scaprile): check on bigendian
+    uint32_t crc, crc_rx;
+    len -= 4;
     crc = mg_crc32(0, (const char *) raw->buf, len);
-    if (memcmp((void *) ((size_t) raw->buf + len), &crc, sizeof(crc)))
+    crc_rx = MG_LOAD_LE32(raw->buf + len);
+    if (crc_rx != crc)
       return false;
   }
   pay->buf = ((char *) eth) + hdrlen;
@@ -130,7 +138,7 @@ bool mg_l2_eth_rx(struct mg_tcpip_if *ifp, enum mg_l2proto *proto,
   for (i = 0; i < sizeof(eth_types) / sizeof(uint16_t); i++) {
     if (type == eth_types[i]) break;
   }
-  if (i == sizeof(eth_types)) {
+  if (i == sizeof(eth_types) / sizeof(eth_types[0])) {
     MG_DEBUG(("Unknown eth type %x", type));
     if (mg_log_level >= MG_LL_VERBOSE)
       mg_hexdump(raw->buf, raw->len >= 32 ? 32 : raw->len);

src/l2_ppp.c

@@ -169,30 +169,14 @@ uint8_t *mg_l2_pppoe_header(struct mg_tcpip_if *ifp, enum mg_l2proto proto,
                                            s_id, src, dst, frame));
 }
 
-// Calculate FCS/CRC for PPP frames. Could be implemented faster using lookup
-// tables.
-static uint16_t fcs_do(uint8_t *frame, size_t len) {
-  uint32_t fcs = 0xffff;
-  unsigned int j;
-  for (j = 0; j < len; j++) {
-    unsigned int i;
-    uint8_t x = frame[j];
-    for (i = 0; i < 8; i++) {
-      fcs = ((fcs ^ x) & 1) ? (fcs >> 1) ^ 0x8408 : fcs >> 1;
-      x >>= 1;
-    }
-  }
-  return (uint16_t) (fcs & 0xffff);
-}
-
 size_t mg_l2_ppp_trailer(struct mg_tcpip_if *ifp, size_t len, uint8_t *cur) {
   uint16_t crc;
   uint8_t *frame;
   len += sizeof(struct ppp) + sizeof(struct hdlc_);
   frame = cur - len;
-  crc = fcs_do(frame, len);
-  *cur++ = (uint8_t) ~crc;  // add CRC, note the byte order
-  *cur++ = (uint8_t) (~crc >> 8);
+  crc = mg_crc16(0, (const char *) frame, len);
+  *cur++ = (uint8_t) crc;  // add CRC, note the byte order
+  *cur++ = (uint8_t) (crc >> 8);
   // there is no len field in PPP
   (void) ifp;
   return len + 2;
@@ -243,6 +227,7 @@ static void ppp_handle_lcp(struct mg_tcpip_if *ifp, uint8_t *lcpp,
   if (lcpsz < sizeof(*lcp)) return;
   id = lcp->id;
   len = mg_ntohs(lcp->len);
+  if (len < sizeof(*lcp) || len > lcpsz) return;
   switch (lcp->code) {
     case MG_PPP_LCP_CFG_REQ: {
       if (len == sizeof(*lcp)) {
@@ -299,7 +284,7 @@ static void ppp_handle_ipcp(struct mg_tcpip_if *ifp, uint8_t *ipcpp,
   if (ipcpsz < sizeof(*ipcp)) return;
   id = ipcp->id;
   len = mg_ntohs(ipcp->len);
-  if (len > ipcpsz) return;
+  if (len < sizeof(*ipcp) || len > ipcpsz) return;
   switch (ipcp->code) {
     case MG_PPP_IPCP_CFG_REQ:
       MG_VERBOSE(("got IPCP config request, acknowledging..."));
@@ -359,6 +344,7 @@ static void ppp_handle_ipv6cp(struct mg_tcpip_if *ifp, uint8_t *ipv6cpp,
   if (ipv6cpsz < sizeof(*ipv6cp)) return;
   id = ipv6cp->id;
   len = mg_ntohs(ipv6cp->len);
+  if (len < sizeof(*ipv6cp) || len > ipv6cpsz) return;
   switch (ipv6cp->code) {
     case MG_PPP_IPV6CP_CFG_REQ:
       MG_VERBOSE(("got IPV6CP config request..."));
@@ -366,10 +352,10 @@ static void ppp_handle_ipv6cp(struct mg_tcpip_if *ifp, uint8_t *ipv6cpp,
           find_opt(
               MG_PPP_IPV6CP_OPT_IFCID, 10, (const uint8_t *) (ipv6cp + 1),
               len - sizeof(*ipv6cp),
-              (uint8_t *) &((struct mg_l2addr *) (ifp->gwmac))->addr.ieee64)) {
-        if (((struct mg_l2addr *) (ifp->gwmac))->addr.ieee64 != 0) {
+              (uint8_t *) &((struct mg_l2addr *) (ifp->gw6mac))->addr.ieee64)) {
+        if (((struct mg_l2addr *) (ifp->gw6mac))->addr.ieee64 != 0) {
           MG_DEBUG(("IPV6CP cfg, GW IFCID: %M", mg_print_ieee64,
-                    &((struct mg_l2addr *) (ifp->gwmac))->addr.ieee64));
+                    &((struct mg_l2addr *) (ifp->gw6mac))->addr.ieee64));
           ipv6cp->code = MG_PPP_IPV6CP_CFG_ACK;
           ppp_tx_frame(ifp, MG_PPP_PROTO_IPV6CP, ipv6cpp, len);
           req[1] = id;
@@ -393,22 +379,21 @@ static void ppp_handle_ipv6cp(struct mg_tcpip_if *ifp, uint8_t *ipv6cpp,
       // Our peer accepted our ifc id
       MG_VERBOSE(("got IPV6CP config ack"));
       break;
-    case MG_PPP_IPV6CP_CFG_NACK:
+    case MG_PPP_IPV6CP_CFG_NACK: {
+      struct mg_l2addr l2;
       MG_VERBOSE(("got IPV6CP config nack"));
       // NACK contains our "suggested" IFC id, use it
       if (len >= 10 &&
-          find_opt(
-              MG_PPP_IPV6CP_OPT_IFCID, 10, (const uint8_t *) (ipv6cp + 1),
-              len - sizeof(*ipv6cp),
-              (uint8_t *) &((struct mg_l2addr *) (ifp->mac))->addr.ieee64)) {
-        MG_DEBUG(("IPV6CP cfg, IFCID: %M", mg_print_ieee64,
-                  &((struct mg_l2addr *) (ifp->mac))->addr.ieee64));
+          find_opt(MG_PPP_IPV6CP_OPT_IFCID, 10, (const uint8_t *) (ipv6cp + 1),
+                   len - sizeof(*ipv6cp), (uint8_t *) &l2.addr.ieee64)) {
+        MG_DEBUG(("IPV6CP cfg, IFCID: %M", mg_print_ieee64, &l2.addr.ieee64));
+        ifp->ip6ll[1] = l2.addr.ieee64;  // RFC-5072 5, signal L3 we're ready
         ipv6cp->code = MG_PPP_IPV6CP_CFG_REQ;
         ppp_tx_frame(ifp, MG_PPP_PROTO_IPV6CP, ipv6cpp, len);
       } else {
         MG_ERROR(("Peer is not able to offer an interface id"));
       }
-      break;
+    } break;
     case MG_PPP_IPV6CP_CFG_REJECT:
       MG_ERROR(("Peer rejected our interface id"));
       break;
@@ -573,10 +558,10 @@ bool mg_l2_pppoe_rx(struct mg_tcpip_if *ifp, enum mg_l2proto *proto,
       uint8_t *p = (uint8_t *) (pppoe + 1);
       uint16_t taglen;
       while (len >= 4) {  // parse tags for a possible AC-Cookie
-        uint16_t curtag = *((uint16_t *) p);
-        taglen = mg_ntohs(*(((uint16_t *) p) + 1));
+        uint16_t curtag = MG_LOAD_BE16(p);
+        taglen = MG_LOAD_BE16(p + 2);
         if (taglen > len - 4) return false;  // truncated / malformed
-        if (curtag == mg_htons(0x0104)) {
+        if (curtag == 0x0104) {
           has_cookie = true;
           break;
         }

src/net.c

@@ -29,6 +29,28 @@ size_t mg_printf(struct mg_connection *c, const char *fmt, ...) {
   return len;
 }
 
+bool mg_dscp(struct mg_connection *c, uint8_t dscp) {
+#if MG_ENABLE_SOCKET
+#if MG_ENABLE_FREERTOS_TCP || MG_ARCH == MG_ARCH_THREADX || \
+    MG_ARCH == MG_ARCH_TIRTOS || MG_ARCH == MG_ARCH_WIN32
+  (void) c;
+  (void) dscp;
+#else
+  int tos = dscp << 2, level = IPPROTO_IP, optname = IP_TOS;
+  c->dscp = (unsigned) (dscp & 63);
+#if MG_ENABLE_IPV6 && !MG_ENABLE_LWIP
+  if (c->loc.is_ip6)
+    level = IPPROTO_IPV6, optname = IPV6_TCLASS;
+#endif
+  return setsockopt((MG_SOCKET_TYPE) (size_t) c->fd, level, optname, (char *) &tos, sizeof(tos)) == 0;
+#endif
+#elif MG_ENABLE_TCPIP
+  c->dscp = (unsigned) (dscp & 63);
+  return true;
+#endif
+  return false;
+}
+
 static bool mg_atonl(struct mg_str str, struct mg_addr *addr) {
   uint32_t localhost = mg_htonl(0x7f000001);
   if (mg_strcasecmp(str, mg_str("localhost")) != 0) return false;
@@ -85,22 +107,31 @@ static bool mg_v4mapped(struct mg_str str, struct mg_addr *addr) {
 
 static bool mg_aton6(struct mg_str str, struct mg_addr *addr) {
   size_t i, j = 0, n = 0, dc = 42;
+  uint16_t val = 0;
+  bool have = false;
   addr->scope_id = 0;
   if (str.len > 2 && str.buf[0] == '[') str.buf++, str.len -= 2;
   if (mg_v4mapped(str, addr)) return true;  // sets addr->is_ip6
   for (i = 0; i < str.len; i++) {
-    if ((str.buf[i] >= '0' && str.buf[i] <= '9') ||
-        (str.buf[i] >= 'a' && str.buf[i] <= 'f') ||
-        (str.buf[i] >= 'A' && str.buf[i] <= 'F')) {
-      unsigned long val = 0;  // TODO(): This loops on chars, refactor
+    int x = str.buf[i] >= '0' && str.buf[i] <= '9'   ? str.buf[i] - '0'
+            : str.buf[i] >= 'a' && str.buf[i] <= 'f' ? str.buf[i] - 'a' + 10
+            : str.buf[i] >= 'A' && str.buf[i] <= 'F' ? str.buf[i] - 'A' + 10
+                                                     : -1;
+    if (x >= 0) {
       if (i > j + 3) return false;
-      // MG_DEBUG(("%lu %lu [%.*s]", i, j, (int) (i - j + 1), &str.buf[j]));
-      mg_str_to_num(mg_str_n(&str.buf[j], i - j + 1), 16, &val, sizeof(val));
-      addr->addr.ip[n] = (uint8_t) ((val >> 8) & 255);
-      addr->addr.ip[n + 1] = (uint8_t) (val & 255);
-    } else if (str.buf[i] == ':') {
+      val = (uint16_t) ((val << 4) | (uint16_t) x);
+      have = true;
+      continue;
+    }
+    if (have) {
+      addr->addr.ip[n] = (uint8_t) (val >> 8),
+      addr->addr.ip[n + 1] = (uint8_t) val;
+      val = 0, have = false;
+    }
+    if (str.buf[i] == ':') {
       j = i + 1;
       if (i > 0 && str.buf[i - 1] == ':') {
+        if (dc != 42) return false;
         dc = n;  // Double colon
         if (i > 1 && str.buf[i - 2] == ':') return false;
       } else if (i > 0) {
@@ -120,12 +151,14 @@ static bool mg_aton6(struct mg_str str, struct mg_addr *addr) {
       return false;
     }
   }
+  if (have)
+    addr->addr.ip[n] = (uint8_t) (val >> 8),
+    addr->addr.ip[n + 1] = (uint8_t) val;
   if (n < 14 && dc == 42) return false;
   if (n < 14) {
     memmove(&addr->addr.ip[dc + (14 - n)], &addr->addr.ip[dc], n - dc + 2);
     memset(&addr->addr.ip[dc], 0, 14 - n);
   }
-
   addr->is_ip6 = true;
   return true;
 }

src/net.h

@@ -74,6 +74,10 @@ struct mg_connection {
   void *pfn_data;                 // Protocol-level handler argument
   char data[MG_DATA_SIZE];        // Scratch space for protocol state; freely readable
   void *tls;                      // TLS state (internal)
+  unsigned dscp : 6;              // Differentiated Services Code Point
+#define MG_DSCP_CS(class_) ((class_) << 3)
+#define MG_DSCP_AF(class_, drop_) (((class_) << 3) | ((drop_) << 1))
+#define MG_DSCP_EF 46
   unsigned is_listening : 1;      // Listening connection; accepts inbound connections
   unsigned is_client : 1;         // Outbound connection created by mg_connect()
   unsigned is_accepted : 1;       // Inbound connection accepted from a listener
@@ -154,6 +158,11 @@ struct mg_connection *mg_connect(struct mg_mgr *, const char *url,
 struct mg_connection *mg_wrapfd(struct mg_mgr *mgr, int fd,
                                 mg_event_handler_t fn, void *fn_data);
 
+// Sets the 6-bit Differentiated Services Code Point for outgoing datagrams.
+// Call on MG_EV_OPEN for UDP listeners, MG_EV_CONNECT for clients, or
+// MG_EV_ACCEPT for TCP servers, before sending application data.
+bool mg_dscp(struct mg_connection *, uint8_t dscp);
+
 // Called internally after DNS resolution completes to create the OS socket
 // and initiate the TCP/IP connect. Normally not called by user code.
 void mg_connect_resolved(struct mg_connection *);

src/net_builtin.c

@@ -46,7 +46,7 @@ struct connstate {
 
 struct ip {
   uint8_t ver;    // Version
-  uint8_t tos;    // Unused
+  uint8_t tos;    // DS field
   uint16_t len;   // Datagram length
   uint16_t id;    // Unused
   uint16_t frag;  // Fragmentation
@@ -412,13 +412,15 @@ static void onstatechange(struct mg_tcpip_if *ifp) {
 }
 
 static struct ip *tx_ip(struct mg_tcpip_if *ifp, uint8_t *l2_dst, uint8_t proto,
-                        uint32_t ip_src, uint32_t ip_dst, size_t plen) {
+                        uint8_t dscp, uint32_t ip_src, uint32_t ip_dst,
+                        size_t plen) {
   // ifp->tx.buf is 8-bit aligned, keep other headers as pointers, see pkt
   uint8_t *l2p = (uint8_t *) ifp->tx.buf;
   struct ip *ip = (struct ip *) mg_l2_header(ifp, MG_TCPIP_L2PROTO_IPV4,
                                              ifp->mac, l2_dst, l2p);
   memset(ip, 0, sizeof(*ip));
-  ip->ver = 0x45;               // Version 4, header length 5 words
+  ip->ver = 0x45;  // Version 4, header length 5 words
+  ip->tos = (uint8_t) (dscp << 2);
   ip->frag = mg_htons(0x4000);  // Don't fragment
   ip->len = mg_htons((uint16_t) (sizeof(*ip) + plen));
   ip->ttl = 64;
@@ -431,12 +433,12 @@ static struct ip *tx_ip(struct mg_tcpip_if *ifp, uint8_t *l2_dst, uint8_t proto,
 
 #if MG_ENABLE_IPV6
 static struct ip6 *tx_ip6(struct mg_tcpip_if *ifp, uint8_t *l2_dst,
-                          uint8_t next, uint64_t *ip_src, uint64_t *ip_dst,
-                          size_t plen);
+                          uint8_t next, uint8_t dscp, uint64_t *ip_src,
+                          uint64_t *ip_dst, size_t plen);
 #endif
 
 static bool tx_udp(struct mg_tcpip_if *ifp, uint8_t *l2_dst,
-                   struct mg_addr *ip_src, struct mg_addr *ip_dst,
+                   struct mg_addr *ip_src, struct mg_addr *ip_dst, uint8_t dscp,
                    const void *buf, size_t len) {
   uint8_t *l3p;
   size_t l2_len;
@@ -445,7 +447,7 @@ static bool tx_udp(struct mg_tcpip_if *ifp, uint8_t *l2_dst,
 #if MG_ENABLE_IPV6
   struct ip6 *ip6 = NULL;
   if (ip_dst->is_ip6) {
-    ip6 = tx_ip6(ifp, l2_dst, 17, ip_src->addr.ip6, ip_dst->addr.ip6,
+    ip6 = tx_ip6(ifp, l2_dst, 17, dscp, ip_src->addr.ip6, ip_dst->addr.ip6,
                  len + sizeof(struct udp));
     udp = (struct udp *) (ip6 + 1);
     l2_len = sizeof(*ip6) + sizeof(*udp) + len;
@@ -453,7 +455,7 @@ static bool tx_udp(struct mg_tcpip_if *ifp, uint8_t *l2_dst,
   } else
 #endif
   {
-    ip = tx_ip(ifp, l2_dst, 17, ip_src->addr.ip4, ip_dst->addr.ip4,
+    ip = tx_ip(ifp, l2_dst, 17, dscp, ip_src->addr.ip4, ip_dst->addr.ip4,
                len + sizeof(struct udp));
     udp = (struct udp *) (ip + 1);
     l2_len = sizeof(*ip) + sizeof(*udp) + len;
@@ -486,7 +488,7 @@ static bool tx_udp4(struct mg_tcpip_if *ifp, uint8_t *l2_dst, uint32_t ip_src,
   memset(&ipd, 0, sizeof(ipd));
   ipd.addr.ip4 = ip_dst;
   ipd.port = dport;
-  return tx_udp(ifp, l2_dst, &ips, &ipd, buf, len);
+  return tx_udp(ifp, l2_dst, &ips, &ipd, 0, buf, len);
 }
 
 static void tx_dhcp(struct mg_tcpip_if *ifp, uint8_t *l2_dst, uint32_t ip_src,
@@ -642,7 +644,7 @@ static void rx_icmp(struct mg_tcpip_if *ifp, struct pkt *pkt) {
     if ((l2addr = get_return_l2addr(ifp, &ips, false, pkt)) == NULL)
       return;  // safety net for lousy networks
     if (plen > room) plen = room;
-    ip = tx_ip(ifp, l2addr, 1, ifp->ip, pkt->ip->src, sizeof(*icmp) + plen);
+    ip = tx_ip(ifp, l2addr, 1, 0, ifp->ip, pkt->ip->src, sizeof(*icmp) + plen);
     icmp = (struct icmp *) (ip + 1);
     memset(icmp, 0, sizeof(*icmp));        // Set csum, type, code to 0
     memcpy(icmp + 1, pkt->pay.buf, plen);  // Copy RX payload to TX
@@ -666,24 +668,31 @@ static void rx_dhcp_client(struct mg_tcpip_if *ifp, struct pkt *pkt) {
           *end = (uint8_t *) &pkt->pay.buf[pkt->pay.len];
   // min header length checked at payload calculation, options are optional
   if (memcmp(&pkt->dhcp->xid, ifp->mac + 2, sizeof(pkt->dhcp->xid))) return;
-  while (p + 1 < end && p[0] != 255) {  // Parse options, get #1; RFC-2132 9
-    if (p[0] == 1 && p[1] == 4 && p + 6 < end) {  // Mask, 3.3
+  while (p < end && p[0] != 255) {  // RFC-2132 9
+    if (p[0] == 0) { p++; continue; }  // Pad
+    if ((size_t) (end - p) < 2 || (size_t) (end - p) < 2U + p[1]) break;
+    if (p[0] == 1) {  // Mask, 3.3
+      if (p[1] != 4) break;
       memcpy(&mask, p + 2, sizeof(mask));
-    } else if (p[0] == 3 && dhcp_opt_len_ok(p[1], p, end)) {  // GW, 3.5
+    } else if (p[0] == 3) {  // GW, 3.5
+      if (!dhcp_opt_len_ok(p[1], p, end)) break;
       memcpy(&gw, p + 2, sizeof(gw));
       ip = pkt->dhcp->yiaddr;
-    } else if (ifp->enable_req_dns && p[0] == 6 &&
-               dhcp_opt_len_ok(p[1], p, end)) {  // DNS, 3.8
+    } else if (ifp->enable_req_dns && p[0] == 6) {  // DNS, 3.8
+      if (!dhcp_opt_len_ok(p[1], p, end)) break;
       memcpy(&dns, p + 2, sizeof(dns));
-    } else if (ifp->enable_req_sntp && p[0] == 42 &&
-               dhcp_opt_len_ok(p[1], p, end)) {  // SNTP, 8.3
+    } else if (ifp->enable_req_sntp && p[0] == 42) {  // SNTP, 8.3
+      if (!dhcp_opt_len_ok(p[1], p, end)) break;
       memcpy(&sntp, p + 2, sizeof(sntp));
-    } else if (p[0] == 51 && p[1] == 4 && p + 6 < end) {  // Lease
+    } else if (p[0] == 51) {  // Lease
+      if (p[1] != 4) break;
       memcpy(&lease, p + 2, sizeof(lease));
       lease = mg_ntohl(lease);
-    } else if (p[0] == 53 && p[1] == 1 && p + 6 < end) {  // Msg Type
+    } else if (p[0] == 53) {  // Msg Type
+      if (p[1] != 1) break;
       msgtype = p[2];
-    } else if (p[0] == 54 && p[1] == 4 && p + 6 < end) {  // Server id 9.7
+    } else if (p[0] == 54) {  // Server id 9.7
+      if (p[1] != 4) break;
       memcpy(&owner, p + 2, sizeof(sntp));  // This is the lease owner
     }
     p += p[1] + 2;
@@ -738,8 +747,11 @@ static void rx_dhcp_server(struct mg_tcpip_if *ifp, struct pkt *pkt) {
   // min header length checked at payload calculation, options are optional
   res.yiaddr = ifp->ip;
   ((uint8_t *) (&res.yiaddr))[3]++;                // Offer our IP + 1
-  while (p + 1 < end && p[0] != 255) {             // Parse options
-    if (p[0] == 53 && p[1] == 1 && p + 2 < end) {  // Message type
+  while (p < end && p[0] != 255) {                 // Parse options
+    if (p[0] == 0) { p++; continue; }              // Pad
+    if ((size_t) (end - p) < 2 || (size_t) (end - p) < 2U + p[1]) break;
+    if (p[0] == 53) {  // Message type
+      if (p[1] != 1) break;
       op = p[2];
     }
     p += p[1] + 2;
@@ -773,14 +785,15 @@ static void rx_dhcp_server(struct mg_tcpip_if *ifp, struct pkt *pkt) {
 
 #if MG_ENABLE_IPV6
 static struct ip6 *tx_ip6(struct mg_tcpip_if *ifp, uint8_t *l2_dst,
-                          uint8_t next, uint64_t *ip_src, uint64_t *ip_dst,
-                          size_t plen) {
+                          uint8_t next, uint8_t dscp, uint64_t *ip_src,
+                          uint64_t *ip_dst, size_t plen) {
   // ifp->tx.buf is 8-bit aligned, keep other headers as pointers, see pkt
   uint8_t *l2p = (uint8_t *) ifp->tx.buf;
   struct ip6 *ip6 = (struct ip6 *) mg_l2_header(ifp, MG_TCPIP_L2PROTO_IPV6,
                                                 ifp->mac, l2_dst, l2p);
   memset(ip6, 0, sizeof(*ip6));
-  ip6->ver = 0x60;  // Version 6, traffic class 0
+  ip6->ver = (uint8_t) (0x60 | (dscp >> 2)); // Version 6, traffic class
+  ip6->label[0] = (uint8_t) (dscp << 6);
   ip6->plen = mg_htons((uint16_t) plen);
   ip6->next = next;
   ip6->hops = 255;  // NDP requires max
@@ -796,7 +809,7 @@ static void tx_icmp6(struct mg_tcpip_if *ifp, uint8_t *l2_dst, uint64_t *ip_src,
                      const void *buf, size_t len) {
   struct ip6 *ip6;
   struct icmp6 *icmp6;
-  ip6 = tx_ip6(ifp, l2_dst, 58, ip_src, ip_dst, sizeof(*icmp6) + len);
+  ip6 = tx_ip6(ifp, l2_dst, 58, 0, ip_src, ip_dst, sizeof(*icmp6) + len);
   icmp6 = (struct icmp6 *) (ip6 + 1);
   memset(icmp6, 0, sizeof(*icmp6));  // Set csum to 0
   icmp6->type = type;
@@ -828,15 +841,16 @@ static void onstate6change(struct mg_tcpip_if *ifp);
 
 static void rx_ndp_na(struct mg_tcpip_if *ifp, struct pkt *pkt) {
   struct ndp_na *na = (struct ndp_na *) pkt->pay.buf;
-  uint8_t *opts = (uint8_t *) (na + 1), *endp = opts + pkt->pay.len - sizeof(*na);
-  if (pkt->pay.len < (sizeof(*na) + 2)) return; // first 2 bytes in opts
-  if ((na->res[0] & 0x40) == 0) return;  // not "solicited"
-  if (*opts++ != 2) return;              // no target hwaddr, must have
+  uint8_t *opts = (uint8_t *) (na + 1),
+          *endp = opts + pkt->pay.len - sizeof(*na);
+  if (pkt->pay.len < (sizeof(*na) + 2)) return;  // first 2 bytes in opts
+  if ((na->res[0] & 0x40) == 0) return;          // not "solicited"
+  if (*opts++ != 2) return;                      // no target hwaddr, must have
   MG_VERBOSE(("NDP NA resp from %M", mg_print_ip6, (char *) &na->addr));
   if (MG_IP6MATCH(na->addr, ifp->gw6)) {
     // Got response for the GW NS request. Set ifp->gw6mac and IP6 -> READY
-    uint8_t len = *opts++;  // check valid hwaddr and get it
-    if ((opts + 8 * len - 2) > endp) return; // truncated
+    uint8_t len = *opts++;                    // check valid hwaddr and get it
+    if ((opts + 8 * len - 2) > endp) return;  // truncated
     if (!mg_l2_ip6get(ifp->l2type, ifp->gw6mac, opts, len)) return;
     ifp->gw6_ready = true;
     if (ifp->state6 == MG_TCPIP_STATE_IP) {
@@ -847,8 +861,8 @@ static void rx_ndp_na(struct mg_tcpip_if *ifp, struct pkt *pkt) {
     struct mg_connection *c = getpeer(ifp->mgr, pkt, false);
     if (c != NULL && c->is_arplooking) {
       struct connstate *s = (struct connstate *) (c + 1);
-      uint8_t len = *opts++;  // check valid hwaddr and get it
-      if ((opts + 8 * len - 2) > endp) return; // truncated
+      uint8_t len = *opts++;                    // check valid hwaddr and get it
+      if ((opts + 8 * len - 2) > endp) return;  // truncated
       if (!mg_l2_ip6get(ifp->l2type, s->mac, opts, len)) return;
       MG_DEBUG(("%lu NDP resolved %M -> %M", c->id, mg_print_ip6,
                 &c->rem.addr.ip6, mg_print_l2addr, ifp->l2type, s->mac));
@@ -860,17 +874,18 @@ static void rx_ndp_na(struct mg_tcpip_if *ifp, struct pkt *pkt) {
 
 // Neighbor Solicitation, 4.3
 static void rx_ndp_ns(struct mg_tcpip_if *ifp, struct pkt *pkt) {
-  struct ndp_na *ns = (struct ndp_na *) pkt->pay.buf; // struct ndp_ns = ndp_na
+  struct ndp_na *ns = (struct ndp_na *) pkt->pay.buf;  // struct ndp_ns = ndp_na
   uint64_t target[2];
-  if (pkt->pay.len < (sizeof(*ns) + 2)) return; // first 2 bytes in opts
+  if (pkt->pay.len < (sizeof(*ns) + 2)) return;  // first 2 bytes in opts
   memcpy(target, ns->addr, sizeof(target));
   if (MG_IP6MATCH(target, ifp->ip6ll) || MG_IP6MATCH(target, ifp->ip6)) {
     uint64_t req[2];  // requester address
     uint8_t l2[sizeof(struct mg_l2addr)];
-    uint8_t len, *opts = (uint8_t *) (ns + 1), *endp = opts + pkt->pay.len - sizeof(*ns);
-    if (*opts++ != 1) return;  // no requester hwaddr (source)
-    len = *opts++;             // check valid hwaddr and get it
-    if ((opts + 8 * len - 2) > endp) return; // truncated
+    uint8_t len, *opts = (uint8_t *) (ns + 1),
+                 *endp = opts + pkt->pay.len - sizeof(*ns);
+    if (*opts++ != 1) return;                 // no requester hwaddr (source)
+    len = *opts++;                            // check valid hwaddr and get it
+    if ((opts + 8 * len - 2) > endp) return;  // truncated
     if (!mg_l2_ip6get(ifp->l2type, l2, opts, len)) return;
     req[0] = pkt->ip6->src[0], req[1] = pkt->ip6->src[1];  // align to 64-bit
     tx_ndp_na(ifp, l2, target, req, true, ifp->mac);
@@ -972,7 +987,7 @@ static void rx_ndp_ra(struct mg_tcpip_if *ifp, struct pkt *pkt) {
   bool gotl2addr = false, gotprefix = false, changed = false;
   uint8_t l2[sizeof(struct mg_l2addr)];
   uint32_t mtu = 0;
-  uint8_t *prefix, prefix_len;
+  uint8_t *prefix = NULL, prefix_len = 0;
 
   if (pkt->pay.len < sizeof(*ra)) return;
   if (ifp->state6 == MG_TCPIP_STATE_UP) {
@@ -989,13 +1004,14 @@ static void rx_ndp_ra(struct mg_tcpip_if *ifp, struct pkt *pkt) {
       } else if (type == 5 && length >= 8) {
         // process MTU if available, ignore if it smells
         mtu = MG_LOAD_BE32(opts + 4);
-        if (mtu < 1280 || mtu > ifp->l2mtu) mtu = 0; // RFC-8200, minimum MTU
+        if (mtu < 1280 || mtu > ifp->l2mtu) mtu = 0;  // RFC-8200, minimum MTU
       } else if (type == 3 && length >= 32) {
-        // process prefix, 4.6.2
+        // process prefix, 4.6.2, ignore if it smells
         uint8_t pfx_flags = opts[3];  // L=0x80, A=0x40
         uint32_t valid = MG_LOAD_BE32(opts + 4);
         uint32_t pref_lifetime = MG_LOAD_BE32(opts + 8);
         prefix_len = opts[2];
+        if (prefix_len >= 128) break;
         prefix = opts + 16;
 
         // TODO (robertc2000): handle prefix options if necessary
@@ -1004,7 +1020,8 @@ static void rx_ndp_ra(struct mg_tcpip_if *ifp, struct pkt *pkt) {
         (void) pref_lifetime;
 
         gotprefix = true;
-        if (prefix_len != ifp->prefix_len || !match_prefix(prefix, ifp->prefix, ifp->prefix_len))
+        if (prefix_len != ifp->prefix_len ||
+            !match_prefix(prefix, ifp->prefix, ifp->prefix_len))
           changed = true;
       }
       opts += length;
@@ -1016,7 +1033,8 @@ static void rx_ndp_ra(struct mg_tcpip_if *ifp, struct pkt *pkt) {
     if (changed) ifp->is_ip6_changed = true;
     ifp->gw6[0] = pkt->ip6->src[0], ifp->gw6[1] = pkt->ip6->src[1];
     if (gotl2addr) memcpy(ifp->gw6mac, l2, sizeof(ifp->gw6mac));
-    if (gotl2addr || ifp->l2type == MG_TCPIP_L2_PPP || ifp->l2type == MG_TCPIP_L2_PPPoE) {
+    if (gotl2addr || ifp->l2type == MG_TCPIP_L2_PPP ||
+        ifp->l2type == MG_TCPIP_L2_PPPoE) {
       ifp->state6 = MG_TCPIP_STATE_READY;
       ifp->gw6_ready = true;
     }
@@ -1101,7 +1119,8 @@ static void onstate6change(struct mg_tcpip_if *ifp) {
       ifp->is_ip6_changed = false;
     }
   } else if (ifp->state6 == MG_TCPIP_STATE_IP) {
-    if ((ifp->gw6[0] != 0 || ifp->gw6[1] != 0) && (ifp->l2type != MG_TCPIP_L2_PPP && ifp->l2type != MG_TCPIP_L2_PPPoE))
+    if ((ifp->gw6[0] != 0 || ifp->gw6[1] != 0) &&
+        (ifp->l2type != MG_TCPIP_L2_PPP && ifp->l2type != MG_TCPIP_L2_PPPoE))
       tx_ndp_ns(ifp, ifp->gw6, NULL);  // unsolicited GW hwaddr resolution
   } else if (ifp->state6 == MG_TCPIP_STATE_UP) {
     MG_INFO(("IP: %M", mg_print_ip6, &ifp->ip6ll));
@@ -1191,8 +1210,8 @@ static bool rx_udp(struct mg_tcpip_if *ifp, struct pkt *pkt) {
 
 static size_t tx_tcp(struct mg_tcpip_if *ifp, uint8_t *l2_dst,
                      struct mg_addr *ip_src, struct mg_addr *ip_dst,
-                     uint8_t flags, uint32_t seq, uint32_t ack, const void *buf,
-                     size_t len) {
+                     uint8_t dscp, uint8_t flags, uint32_t seq, uint32_t ack,
+                     const void *buf, size_t len) {
   uint8_t *l3p;
   struct ip *ip = NULL;
   struct tcp *tcp;
@@ -1217,14 +1236,15 @@ static size_t tx_tcp(struct mg_tcpip_if *ifp, uint8_t *l2_dst,
 
 #if MG_ENABLE_IPV6
   if (ip_dst->is_ip6) {
-    ip6 =
-        tx_ip6(ifp, l2_dst, 6, ip_src->addr.ip6, ip_dst->addr.ip6, hlen + len);
+    ip6 = tx_ip6(ifp, l2_dst, 6, dscp, ip_src->addr.ip6, ip_dst->addr.ip6,
+                 hlen + len);
     tcp = (struct tcp *) (ip6 + 1);
     l3p = (uint8_t *) ip6;
   } else
 #endif
   {
-    ip = tx_ip(ifp, l2_dst, 6, ip_src->addr.ip4, ip_dst->addr.ip4, hlen + len);
+    ip = tx_ip(ifp, l2_dst, 6, dscp, ip_src->addr.ip4, ip_dst->addr.ip4,
+               hlen + len);
     tcp = (struct tcp *) (ip + 1);
     l3p = (uint8_t *) ip;
   }
@@ -1274,11 +1294,12 @@ static size_t tx_tcp_ctrlresp(struct mg_tcpip_if *ifp, struct pkt *pkt,
   ipd.port = pkt->tcp->sport;
   if ((l2addr = get_return_l2addr(ifp, &ipd, false, pkt)) == NULL)
     return 0;  // safety net for lousy networks
-  return tx_tcp(ifp, l2addr, &ips, &ipd, flags, seqno, ackno, NULL, 0);
+  return tx_tcp(ifp, l2addr, &ips, &ipd, 0, flags, seqno, ackno, NULL, 0);
 }
 
 static size_t tx_tcp_rst(struct mg_tcpip_if *ifp, struct pkt *pkt, bool toack) {
-  return tx_tcp_ctrlresp(ifp, pkt, toack ? TH_RST : (TH_RST | TH_ACK),
+  return tx_tcp_ctrlresp(ifp, pkt,
+                         (uint8_t) (toack ? TH_RST : (TH_RST | TH_ACK)),
                          toack ? pkt->tcp->ack : 0);
 }
 
@@ -1294,7 +1315,7 @@ static struct mg_connection *accept_conn(struct mg_connection *lsn,
   s = (struct connstate *) (c + 1);
   s->dmss = mss;  // from options in client SYN
   s->seq = mg_ntohl(pkt->tcp->ack), s->ack = mg_ntohl(pkt->tcp->seq);
-  s->win = mg_ntohs(pkt->tcp->win), s->maxseq = (uint32_t)(s->seq + s->win);
+  s->win = mg_ntohs(pkt->tcp->win), s->maxseq = (uint32_t) (s->seq + s->win);
 #if MG_ENABLE_IPV6
   if (lsn->loc.is_ip6) {
     c->rem.addr.ip6[0] = pkt->ip6->src[0],
@@ -1379,7 +1400,7 @@ static bool udp_send(struct mg_connection *c, const void *buf, size_t len) {
     ips.addr.ip4 = ifp->ip;
   }
   ips.port = c->loc.port;
-  return tx_udp(ifp, s->mac, &ips, &c->rem, buf, len);
+  return tx_udp(ifp, s->mac, &ips, &c->rem, c->dscp, buf, len);
 }
 
 long mg_io_send(struct mg_connection *c, const void *buf, size_t len) {
@@ -1394,7 +1415,7 @@ long mg_io_send(struct mg_connection *c, const void *buf, size_t len) {
     if (room == 0) return MG_IO_WAIT;
     if (len > s->dmss) len = s->dmss;  // RFC-6691: reduce if sending opts
     if ((uint32_t) len > room) len = room;
-    sent = tx_tcp(ifp, s->mac, &c->loc, &c->rem, TH_PUSH | TH_ACK,
+    sent = tx_tcp(ifp, s->mac, &c->loc, &c->rem, c->dscp, TH_PUSH | TH_ACK,
                   mg_htonl(s->seq), mg_htonl(s->ack), buf, len);
     if (sent == 0) {
       return MG_IO_WAIT;
@@ -1409,16 +1430,16 @@ long mg_io_send(struct mg_connection *c, const void *buf, size_t len) {
 }
 
 static void handle_tls_recv(struct mg_connection *c) {
-  size_t avail = mg_tls_pending(c); // will change after mg_tls_recv()
+  size_t avail = mg_tls_pending(c);  // will change after mg_tls_recv()
   size_t min = avail > MG_MAX_RECV_SIZE ? MG_MAX_RECV_SIZE : avail;
-  struct mg_iobuf *io = &c->recv; // allocated on first avail > 0
+  struct mg_iobuf *io = &c->recv;  // allocated on first avail > 0
   if (io->size - io->len < min && !mg_iobuf_resize(io, io->len + min)) {
     mg_error(c, "oom");
   } else {
     // Decrypt data directly into c->recv. If io->buf = NULL or
     // io->len = io->size (no room), there can be outstanding data that can't be
-    // moved (mg_tls_pending() > 0 after mg_tls_recv() returns). So mg_tls_recv()
-    // takes care of returning 0 in this case (commented as "MIP")
+    // moved (mg_tls_pending() > 0 after mg_tls_recv() returns). So
+    // mg_tls_recv() takes care of returning 0 in this case (commented as "MIP")
     long n = mg_tls_recv(c, io->buf != NULL ? &io->buf[io->len] : io->buf,
                          io->size - io->len);
     if (n == MG_IO_ERR) {
@@ -1433,7 +1454,7 @@ static void handle_tls_recv(struct mg_connection *c) {
 
 static void handle_ack(struct connstate *s, uint32_t ackno, uint16_t win) {
   if (ackno < (s->seq - s->win) || ackno > s->seq) return;
-  s->maxseq = (uint32_t)(ackno + win);
+  s->maxseq = (uint32_t) (ackno + win);
   s->win = win;
 }
 
@@ -1445,8 +1466,8 @@ static void read_conn(struct mg_connection *c, struct pkt *pkt) {
     uint8_t flags = TH_ACK;
     if (mg_ntohl(pkt->tcp->seq) != s->ack) {
       MG_VERBOSE(("ignoring FIN, %x != %x", mg_ntohl(pkt->tcp->seq), s->ack));
-      tx_tcp(c->mgr->ifp, s->mac, &c->loc, &c->rem, TH_ACK, mg_htonl(s->seq),
-             mg_htonl(s->ack), "", 0);
+      tx_tcp(c->mgr->ifp, s->mac, &c->loc, &c->rem, c->dscp, TH_ACK,
+             mg_htonl(s->seq), mg_htonl(s->ack), "", 0);
       return;
     }
     // If we initiated the closure, we reply with ACK upon receiving FIN
@@ -1467,14 +1488,14 @@ static void read_conn(struct mg_connection *c, struct pkt *pkt) {
       // is flushed, then send our FIN.
       c->is_draining = 1;
     }
-    tx_tcp(c->mgr->ifp, s->mac, &c->loc, &c->rem, flags, mg_htonl(s->seq),
-           mg_htonl(s->ack), "", 0);
+    tx_tcp(c->mgr->ifp, s->mac, &c->loc, &c->rem, c->dscp, flags,
+           mg_htonl(s->seq), mg_htonl(s->ack), "", 0);
     if (pkt->pay.len == 0) return;  // if no data, we're done
   } else if (pkt->pay.len <= 1 && mg_ntohl(pkt->tcp->seq) == s->ack - 1) {
     // Keep-Alive (RFC-9293 3.8.4, allow erroneous implementations)
     MG_VERBOSE(("%lu keepalive ACK", c->id));
-    tx_tcp(c->mgr->ifp, s->mac, &c->loc, &c->rem, TH_ACK, mg_htonl(s->seq),
-           mg_htonl(s->ack), NULL, 0);
+    tx_tcp(c->mgr->ifp, s->mac, &c->loc, &c->rem, c->dscp, TH_ACK,
+           mg_htonl(s->seq), mg_htonl(s->ack), NULL, 0);
     return;                        // no data to process
   } else if (pkt->pay.len == 0) {  // this is an ACK
     if (pkt->tcp->flags & TH_ACK)
@@ -1487,8 +1508,8 @@ static void read_conn(struct mg_connection *c, struct pkt *pkt) {
       MG_VERBOSE(("ignoring duplicate pkt"));
     } else {
       MG_VERBOSE(("SEQ != ACK: %x %x %x", seq, s->ack, ack));
-      tx_tcp(c->mgr->ifp, s->mac, &c->loc, &c->rem, TH_ACK, mg_htonl(s->seq),
-             mg_htonl(s->ack), "", 0);
+      tx_tcp(c->mgr->ifp, s->mac, &c->loc, &c->rem, c->dscp, TH_ACK,
+             mg_htonl(s->seq), mg_htonl(s->ack), "", 0);
     }
     return;  // drop it
   } else if (io->size - io->len < pkt->pay.len &&
@@ -1496,8 +1517,8 @@ static void read_conn(struct mg_connection *c, struct pkt *pkt) {
     mg_error(c, "oom");
     return;  // drop it
   }
-    if (pkt->tcp->flags & TH_ACK)
-      handle_ack(s, mg_ntohl(pkt->tcp->ack), mg_ntohs(pkt->tcp->win));
+  if (pkt->tcp->flags & TH_ACK)
+    handle_ack(s, mg_ntohl(pkt->tcp->ack), mg_ntohs(pkt->tcp->win));
   // Copy TCP payload into the IO buffer. If the connection is plain text,
   // we copy to c->recv. If the connection is TLS, this data is encrypted,
   // therefore we copy that encrypted data to the c->rtls iobuffer instead,
@@ -1513,8 +1534,8 @@ static void read_conn(struct mg_connection *c, struct pkt *pkt) {
   if (s->unacked > MG_TCPIP_WIN / 2 && s->acked != s->ack) {
     // Send ACK immediately
     MG_VERBOSE(("%lu imm ACK %lu", c->id, s->acked));
-    tx_tcp(c->mgr->ifp, s->mac, &c->loc, &c->rem, TH_ACK, mg_htonl(s->seq),
-           mg_htonl(s->ack), NULL, 0);
+    tx_tcp(c->mgr->ifp, s->mac, &c->loc, &c->rem, c->dscp, TH_ACK,
+           mg_htonl(s->seq), mg_htonl(s->ack), NULL, 0);
     s->unacked = 0;
     s->acked = s->ack;
     if (s->ttype != MIP_TTYPE_KEEPALIVE) settmout(c, MIP_TTYPE_KEEPALIVE);
@@ -1587,9 +1608,9 @@ static bool handle_opt(struct connstate *s, struct tcp *tcp, bool ip6) {
   s->dmss = ip6 ? 1220 : 536;  // assume default, RFC-9293 3.7.1
   while (len > 0) {            // RFC-9293 3.1 3.2
     uint8_t kind = opts[0], optlen = 1;
-    if (kind != 1) {                              // No-Operation
-      if (kind == 0) break;                       // End of Option List
-      if (len < 2 || opts[1] == 0) return false;  // Malformed options
+    if (kind != 1) {         // No-Operation
+      if (kind == 0) break;  // End of Option List
+      if (len < 2 || opts[1] == 0 || opts[1] > len) return false;  // Malformed
       optlen = opts[1];
       if (kind == 2 && optlen == 4)  // set received MSS
         s->dmss = (uint16_t) (((uint16_t) opts[2] << 8) + opts[3]);
@@ -1616,7 +1637,7 @@ static void rx_tcp(struct mg_tcpip_if *ifp, struct pkt *pkt) {
     if (!handle_opt(s, pkt->tcp, pkt->ip6 != NULL))
       return;  // process options (MSS)
     s->seq = mg_ntohl(pkt->tcp->ack), s->ack = mg_ntohl(pkt->tcp->seq) + 1;
-    s->win = mg_ntohs(pkt->tcp->win), s->maxseq = (uint32_t)(s->seq + s->win);
+    s->win = mg_ntohs(pkt->tcp->win), s->maxseq = (uint32_t) (s->seq + s->win);
     tx_tcp_ctrlresp(ifp, pkt, TH_ACK, pkt->tcp->ack);
     c->is_connecting = 0;  // Client connected
     settmout(c, MIP_TTYPE_KEEPALIVE);
@@ -1922,11 +1943,12 @@ static void mg_ip6_poll(struct mg_tcpip_if *ifp, bool s1) {
 static void mg_ip6_link(struct mg_tcpip_if *ifp, bool drv_up, bool l2_up) {
   bool cur_drv = (ifp->state6 != MG_TCPIP_STATE_DOWN);
   bool cur_l2 = (ifp->state6 >= MG_TCPIP_STATE_UP);
+  const uint8_t px[8] = {0xfe, 0x80, 0, 0, 0, 0, 0, 0};  // RFC-4291 2.5.6
   if (drv_up != cur_drv || l2_up != cur_l2) {  // link/L2 state has changed
-    if (l2_up && ifp->ip6ll[0] == 0 && ifp->ip6ll[1] == 0) { // gen ll address
-      uint8_t px[8] = {0xfe, 0x80, 0, 0, 0, 0, 0, 0};  // RFC-4291 2.5.6
+    if (ifp->l2type == MG_TCPIP_L2_ETH && l2_up && ifp->ip6ll[0] == 0 &&
+        ifp->ip6ll[1] == 0) {  // gen ll address
       mg_l2_genip6(ifp->l2type, ifp->ip6ll, 64, ifp->mac);
-      memcpy(ifp->ip6ll, px, 8);  // RFC-4291 2.5.4
+      memcpy(ifp->ip6ll, px, 8);  // RFC-2464 5
     }  // just got our link local address if we didn't have one.
     // If static configuration is used, global addresses,
     // prefix length, and gw are already filled at this point.
@@ -1934,14 +1956,21 @@ static void mg_ip6_link(struct mg_tcpip_if *ifp, bool drv_up, bool l2_up) {
     if (!l2_up && ifp->enable_slaac) ifp->ip6[0] = ifp->ip6[1] = 0;
     ifp->state6 = !drv_up  ? MG_TCPIP_STATE_DOWN
                   : !l2_up ? MG_TCPIP_STATE_LINK_UP
-                  : ifp->enable_slaac || ifp->ip6[0] == 0 ? MG_TCPIP_STATE_UP
-                                                          : MG_TCPIP_STATE_IP;
+                  : ifp->ip6ll[0] == 0 || ifp->enable_slaac || ifp->ip6[0] == 0
+                      ? MG_TCPIP_STATE_UP
+                      : MG_TCPIP_STATE_IP;
     onstate6change(ifp);
   } else if (!ifp->enable_slaac && ifp->state6 == MG_TCPIP_STATE_UP &&
-             ifp->ip6[0]) {
+             ifp->ip6ll[0] != 0 && ifp->ip6[0] != 0) {
     ifp->state6 = MG_TCPIP_STATE_IP;  // ifp->fn has set an IP
     onstate6change(ifp);
   }
+  if ((ifp->l2type == MG_TCPIP_L2_PPP || ifp->l2type == MG_TCPIP_L2_PPPoE) &&
+      ifp->state6 == MG_TCPIP_STATE_UP && ifp->ip6ll[0] == 0 &&
+      ifp->ip6ll[1] != 0) {     // IPV6CP has got an IFCID, gen ll address
+    memcpy(ifp->ip6ll, px, 8);  // RFC-5072 5
+    onstate6change(ifp);
+  }  // just got our link local address if we didn't have one.
 }
 #else
 #define mg_ip6_poll(x, y)
@@ -1994,8 +2023,8 @@ static void mg_tcpip_poll(struct mg_tcpip_if *ifp, uint64_t now) {
     drv_up = ifp->driver->poll ? ifp->driver->poll(ifp, expired_1000ms) : true;
     l2_up = mg_l2_poll(ifp, expired_1000ms);  // Handle L2 up/down link status;
     if (expired_1000ms) {                     // ifp->state rules over state6
-      mg_ip_link(ifp, drv_up, l2_up);             // Handle IPv4
-      mg_ip6_link(ifp, drv_up, l2_up);            // Handle IPv6
+      mg_ip_link(ifp, drv_up, l2_up);         // Handle IPv4
+      mg_ip6_link(ifp, drv_up, l2_up);        // Handle IPv6
       if (ifp->state < MG_TCPIP_STATE_UP) MG_ERROR(("Network is down"));
       mg_tcpip_call(ifp, MG_TCPIP_EV_TIMER_1S, NULL);
     }
@@ -2034,7 +2063,7 @@ static void mg_tcpip_poll(struct mg_tcpip_if *ifp, uint64_t now) {
         continue;
       } else if (s->ttype == MIP_TTYPE_ACK && s->acked != s->ack) {
         MG_VERBOSE(("%lu ack %x %x", c->id, s->seq, s->ack));
-        tx_tcp(ifp, s->mac, &c->loc, &c->rem, TH_ACK, mg_htonl(s->seq),
+        tx_tcp(ifp, s->mac, &c->loc, &c->rem, c->dscp, TH_ACK, mg_htonl(s->seq),
                mg_htonl(s->ack), NULL, 0);
         s->acked = s->ack;
       } else if (s->ttype == MIP_TTYPE_SYN) {
@@ -2047,8 +2076,8 @@ static void mg_tcpip_poll(struct mg_tcpip_if *ifp, uint64_t now) {
           mg_error(c, "keepalive");
         } else {
           MG_VERBOSE(("%lu keepalive", c->id));
-          tx_tcp(ifp, s->mac, &c->loc, &c->rem, TH_ACK, mg_htonl(s->seq - 1),
-                 mg_htonl(s->ack), NULL, 0);
+          tx_tcp(ifp, s->mac, &c->loc, &c->rem, c->dscp, TH_ACK,
+                 mg_htonl(s->seq - 1), mg_htonl(s->ack), NULL, 0);
         }
       }
 
@@ -2111,7 +2140,8 @@ void mg_tcpip_free(struct mg_tcpip_if *ifp) {
 static void send_syn(struct mg_connection *c) {
   struct connstate *s = (struct connstate *) (c + 1);
   uint32_t isn = mg_htonl((uint32_t) mg_ntohs(c->loc.port));
-  tx_tcp(c->mgr->ifp, s->mac, &c->loc, &c->rem, TH_SYN, isn, 0, NULL, 0);
+  tx_tcp(c->mgr->ifp, s->mac, &c->loc, &c->rem, c->dscp, TH_SYN, isn, 0, NULL,
+         0);
 }
 
 static void l2addr_resolved(struct mg_connection *c) {
@@ -2132,9 +2162,9 @@ void mg_connect_resolved(struct mg_connection *c) {
   c->loc.port = mg_htons(ifp->eport++);
 #if MG_ENABLE_IPV6
   if (c->rem.is_ip6) {
-    if(c->rem.addr.ip6[0] == ifp->ip6ll[0]) { // same local LAN, use ll
+    if (c->rem.addr.ip6[0] == ifp->ip6ll[0]) {  // same local LAN, use ll
       c->loc.addr.ip6[0] = ifp->ip6ll[0], c->loc.addr.ip6[1] = ifp->ip6ll[1];
-    } else { // use global address
+    } else {  // use global address
       c->loc.addr.ip6[0] = ifp->ip6[0], c->loc.addr.ip6[1] = ifp->ip6[1];
     }
     c->loc.is_ip6 = true;
@@ -2214,7 +2244,7 @@ static void init_closure(struct mg_connection *c) {
   struct connstate *s = (struct connstate *) (c + 1);
   if (c->is_udp == false && c->is_listening == false &&
       c->is_connecting == false) {  // For TCP conns,
-    tx_tcp(c->mgr->ifp, s->mac, &c->loc, &c->rem, TH_FIN | TH_ACK,
+    tx_tcp(c->mgr->ifp, s->mac, &c->loc, &c->rem, c->dscp, TH_FIN | TH_ACK,
            mg_htonl(s->seq), mg_htonl(s->ack), NULL, 0);
     settmout(c, MIP_TTYPE_FIN);
   }

src/net_ft.h

@@ -29,7 +29,8 @@
   ((errcode) == -pdFREERTOS_ERRNO_EWOULDBLOCK || \
    (errcode) == -pdFREERTOS_ERRNO_EISCONN ||     \
    (errcode) == -pdFREERTOS_ERRNO_EINPROGRESS || \
-   (errcode) == -pdFREERTOS_ERRNO_EAGAIN)
+   (errcode) == -pdFREERTOS_ERRNO_EAGAIN ||      \
+   (errcode) == -pdFREERTOS_ERRNO_ENOSPC)
 
 #define MG_SOCK_RESET(errcode) ((errcode) == -pdFREERTOS_ERRNO_ENOTCONN)
 

src/ota.c

@@ -3,6 +3,7 @@
 #include "json.h"
 #include "log.h"
 #include "printf.h"
+#include "tls.h"
 #include "url.h"
 #include "util.h"
 
@@ -26,6 +27,19 @@ static struct mg_ota_state {
 
 static void s_firmware_fn(struct mg_connection *c, int ev, void *ev_data);
 
+static bool s_tls_init(struct mg_connection *c, const char *url) {
+  struct mg_tls_opts opts;
+  memset(&opts, 0, sizeof(opts));
+  opts.ca = mg_str(MG_OTA_TLS_CA);
+  opts.name = mg_url_host(url);
+  if (opts.ca.len == 0) {
+    mg_error(c, "MG_OTA_TLS_CA is not configured");
+  } else {
+    mg_tls_init(c, &opts);
+  }
+  return c->is_tls_hs != 0 && !c->is_closing;
+}
+
 #if MG_ENABLE_CUSTOM_DEVICE_ID
 #else
 void mg_ota_device_id(char *buf, size_t len) {
@@ -58,6 +72,11 @@ void mg_ota_device_id(char *buf, size_t len) {
 
 static void s_version_fn(struct mg_connection *c, int ev, void *ev_data) {
   uint64_t expiration = *(uint64_t *) c->data;
+  if (s_ota == NULL) {
+    c->fn = NULL;
+    c->is_closing = 1;
+    return;
+  }
   if (ev == MG_EV_POLL) {
     if (mg_millis() > expiration) mg_error(c, "Metadata timeout");
   } else if (ev == MG_EV_CONNECT) {
@@ -65,6 +84,9 @@ static void s_version_fn(struct mg_connection *c, int ev, void *ev_data) {
     struct mg_str host = mg_url_host(s_ota->json_url);
     const char *uri = mg_url_uri(s_ota->json_url);
     const char *sep = strchr(uri, '?') == NULL ? "?" : "&";
+    if (mg_url_is_ssl(s_ota->json_url)) {
+      if (!s_tls_init(c, s_ota->json_url)) return;
+    }
     mg_ota_device_id(id, sizeof(id));
     id[sizeof(id) - 1] = '\0';
     mg_printf(
@@ -130,10 +152,18 @@ static void status_fn_2(struct mg_connection *c, const char *errmsg) {
 
 static void s_firmware_fn(struct mg_connection *c, int ev, void *ev_data) {
   uint64_t expiration = *(uint64_t *) c->data;
+  if (s_ota == NULL) {
+    c->fn = NULL;
+    c->is_closing = 1;
+    return;
+  }
   if (ev == MG_EV_POLL) {
     if (mg_millis() > expiration) mg_error(c, "OTA timeout");
   } else if (ev == MG_EV_CONNECT) {
     struct mg_str host = mg_url_host(s_ota->url);
+    if (mg_url_is_ssl(s_ota->url)) {
+      if (!s_tls_init(c, s_ota->url)) return;
+    }
     mg_printf(c,
               "GET %s HTTP/1.1\r\n"
               "Host: %.*s\r\n"
@@ -185,7 +215,7 @@ void mg_ota_poll(struct mg_mgr *mgr) {
   static uint64_t t = 5000;  // Fire first time 5 sec after boot
 
   static uint64_t feed_timer;  // Advances 500ms per tick; tracks elapsed time
-  if (MG_OTA_STATE_GET() == MG_OTA_TESTING &&
+  if (MG_OTA_STATE_GET() == MG_OTA_FAILED &&
       mg_timer_expired(&feed_timer, 500, mg_millis())) {
     if (feed_timer < (uint64_t) MG_OTA_ROLLBACK_TIMEOUT_SECONDS * 1000) {
       MG_OTA_ROLLBACK_TIMER_FEED();  // Feed watchdog every 500ms

src/ota.h

@@ -2,7 +2,7 @@
 //
 // This is a low-level OTA API, not intended to be called directly by users.
 // Users are provided with a higher-level API:
-// - defining MG_OTA_URL enables HTTP pull-based updates
+// - defining MG_OTA_URL enables HTTP or HTTPS pull-based updates
 // - mg_http_start_ota() enables push-based updates
 //
 // However, it is possible to use the mg_ota_* API directly. Below is the
@@ -149,8 +149,10 @@ enum {
     }                                                              \
   } while (0)
 
-// Pull-based OTA over HTTP. Fetches metadata_url, which must return a JSON
-// object like: { "version": "1.2.3", "url": "FIRMWARE_URL", "size": 324645 }
+// Pull-based OTA over HTTP or HTTPS. If it's HTTPS, MG_OTA_TLS_CA
+// needs to be defined. Fetches metadata_url, which must
+// return a JSON object like:
+// { "version": "1.2.3", "url": "FIRMWARE_URL", "size": 324645 }
 // If the server version differs from MG_OTA_FIRMWARE_VERSION, downloads
 // FIRMWARE_URL and performs the OTA update. fn is called on every outcome:
 // NULL on successful flash, "Same version" when already up to date, or an
@@ -160,12 +162,18 @@ void mg_ota_url_check(struct mg_mgr *mgr, const char *metadata_url,
                       void (*fn)(const char *error_message));
 
 // Firmware info URL for mg_ota_poll() which calls mg_ota_url_check().
-// Example:  "http://mongoose.ws/ota/u/0/ota.json". See http://mongoose.ws/ota/
+// Example: "http://mongoose.ws/ota/u/0/ota.json". See http://mongoose.ws/ota/
 // Settable in mongoose_config.h
 #ifndef MG_OTA_URL
 #define MG_OTA_URL NULL
 #endif
 
+// PEM or DER CA certificate used to authenticate an HTTPS OTA server. Set to
+// NULL to use HTTP. Set in mongoose_config.h.
+#ifndef MG_OTA_TLS_CA
+#define MG_OTA_TLS_CA NULL
+#endif
+
 // OTA status callback function for mg_ota_poll()
 #ifndef MG_OTA_STATUS_FN
 #define MG_OTA_STATUS_FN NULL
@@ -195,6 +203,7 @@ void mg_ota_url_check(struct mg_mgr *mgr, const char *metadata_url,
 // E.g. on STM32, uses the 96-bit MCU UID converted to a hex string.
 void mg_ota_device_id(char *buf, size_t len);
 
-// Checks for a firmware update over HTTP. Called automatically by mg_mgr_poll()
-// when MG_OTA_URL is set in mongoose_config.h. Do not call directly.
+// Checks for a firmware update over HTTP or HTTPS. Called automatically by
+// mg_mgr_poll() when MG_OTA_URL is set in mongoose_config.h. Do not call
+// directly.
 void mg_ota_poll(struct mg_mgr *);

src/ota_esp32.c

@@ -46,6 +46,10 @@ bool mg_ota_end(void) {
   }
   MG_DEBUG(("Finished ESP32 OTA, success: %d", s_ota_success));
   s_ota_update_partition = NULL;
+  if (s_ota_success) {
+    MG_OTA_STATE_SET(MG_OTA_TESTING);
+    esp_restart();
+  }
   return s_ota_success;
 }
 

src/ota_imxrt.c

@@ -491,10 +491,6 @@ MG_IRAM static bool mg_imxrt_erase(void *addr) {
 }
 #endif
 
-MG_IRAM bool mg_imxrt_swap(void) {
-  return true;
-}
-
 MG_IRAM static bool mg_imxrt_write(void *addr, const void *buf, size_t len) {
   struct mg_flexspi_nor_config config, *config_ptr = &config;
   bool ok = false;
@@ -550,16 +546,40 @@ fwxit:
   return ok;
 }
 
-// just overwrite instead of swap
 MG_IRAM static void single_bank_swap(char *p1, char *p2, size_t s, size_t ss) {
-  // no stdlib calls here
+  char *scratch = p2 + s;
   for (size_t ofs = 0; ofs < s; ofs += ss) {
+    MG_OTA_ROLLBACK_TIMER_FEED();
+    mg_imxrt_write(scratch, p1 + ofs, ss);
+    MG_OTA_ROLLBACK_TIMER_FEED();
     mg_imxrt_write(p1 + ofs, p2 + ofs, ss);
+    MG_OTA_ROLLBACK_TIMER_FEED();
+    mg_imxrt_write(p2 + ofs, scratch, ss);
   }
   *(volatile unsigned long *) 0xe000ed0c = 0x5fa0004;
 }
 
+MG_IRAM static bool mg_imxrt_swap(void) {
+  size_t ss = s_mg_flash_imxrt.secsz;
+  char *p1 = (char *) s_mg_flash_imxrt.start;
+  char *p2 = p1 + s_mg_flash_imxrt.size / 2;
+  size_t s = s_mg_flash_imxrt.size / 2 - ss;
+  MG_INFO(("Swapping partitions, %u bytes", s));
+  MG_INFO(("Do NOT power off..."));
+  MG_OTA_ROLLBACK_TIMER_FEED();
+  mg_log_level = MG_LL_NONE;
+  s_flash_irq_disabled = true;
+  single_bank_swap(p1, p2, s, ss);
+  return true;  // unreachable
+}
+
 bool mg_ota_begin(size_t new_firmware_size) {
+  size_t max = s_mg_flash_imxrt.size / 2 - s_mg_flash_imxrt.secsz;
+  if (new_firmware_size > max) {
+    MG_ERROR(("Firmware %lu too big for single-bank OTA, max %lu",
+              new_firmware_size, max));
+    return false;
+  }
   return mg_ota_flash_begin(new_firmware_size, &s_mg_flash_imxrt);
 }
 
@@ -568,25 +588,7 @@ bool mg_ota_write(const void *buf, size_t len) {
 }
 
 bool mg_ota_end(void) {
-  if (mg_ota_flash_end(&s_mg_flash_imxrt)) {
-    if (0) {  // is_dualbank()
-      // TODO(): no devices so far
-      *(volatile unsigned long *) 0xe000ed0c = 0x5fa0004;
-    } else {
-      // Swap partitions. Pray power does not go away
-      MG_INFO(("Swapping partitions, size %u (%u sectors)",
-               s_mg_flash_imxrt.size,
-               s_mg_flash_imxrt.size / s_mg_flash_imxrt.secsz));
-      MG_INFO(("Do NOT power off..."));
-      mg_log_level = MG_LL_NONE;
-      s_flash_irq_disabled = true;
-      // Runs in RAM, will reset when finished
-      single_bank_swap(
-          (char *) s_mg_flash_imxrt.start,
-          (char *) s_mg_flash_imxrt.start + s_mg_flash_imxrt.size / 2,
-          s_mg_flash_imxrt.size / 2, s_mg_flash_imxrt.secsz);
-    }
-  }
+  mg_ota_flash_end(&s_mg_flash_imxrt);
   return false;
 }
 struct mg_flash *mg_flash = &s_mg_flash_imxrt;

src/ota_stm32f.c

@@ -45,11 +45,9 @@ MG_IRAM static int is_dualbank(void) {
 }
 
 MG_IRAM static void flash_unlock(void) {
-  static bool unlocked = false;
-  if (unlocked == false) {
+  if (MG_REG(MG_FLASH_BASE + MG_FLASH_CR) & MG_BIT(31)) {
     MG_REG(MG_FLASH_BASE + MG_FLASH_KEYR) = 0x45670123;
     MG_REG(MG_FLASH_BASE + MG_FLASH_KEYR) = 0xcdef89ab;
-    unlocked = true;
   }
 }
 

src/ota_stm32h5.c

@@ -39,13 +39,14 @@ static uint32_t sectors_per_bank(void) {
 }
 
 static void flash_unlock(void) {
-  static bool unlocked = false;
-  if (unlocked == false) {
+  if (MG_REG(FLASH_NSCR) & MG_BIT(0)) {
     MG_REG(FLASH_KEYR) = 0x45670123;
-    MG_REG(FLASH_KEYR) = 0Xcdef89ab;
+    MG_REG(FLASH_KEYR) = 0xcdef89ab;
+  }
+
+  if (MG_REG(FLASH_OPTCR) & MG_BIT(0)) {
     MG_REG(FLASH_OPTKEYR) = 0x08192a3b;
     MG_REG(FLASH_OPTKEYR) = 0x4c5d6e7f;
-    unlocked = true;
   }
 }
 

src/ota_stm32h7.c

@@ -53,17 +53,17 @@ MG_IRAM static bool is_dualbank(void) {
 }
 
 MG_IRAM static void flash_unlock(void) {
-  static bool unlocked = false;
-  if (unlocked == false) {
-    MG_REG(FLASH_BASE1 + FLASH_KEYR) = 0x45670123;
-    MG_REG(FLASH_BASE1 + FLASH_KEYR) = 0xcdef89ab;
-    if (is_dualbank()) {
-      MG_REG(FLASH_BASE2 + FLASH_KEYR) = 0x45670123;
-      MG_REG(FLASH_BASE2 + FLASH_KEYR) = 0xcdef89ab;
-    }
-    MG_REG(FLASH_BASE1 + FLASH_OPTKEYR) = 0x08192a3b;  // opt reg is "shared"
-    MG_REG(FLASH_BASE1 + FLASH_OPTKEYR) = 0x4c5d6e7f;  // thus unlock once
-    unlocked = true;
+  if (MG_REG(FLASH_BASE1 + FLASH_CR) & MG_BIT(0)) {
+	  MG_REG(FLASH_BASE1 + FLASH_KEYR) = 0x45670123;
+	  MG_REG(FLASH_BASE1 + FLASH_KEYR) = 0xcdef89ab;
+  }
+  if (is_dualbank() && MG_REG(FLASH_BASE2 + FLASH_CR) & MG_BIT(0)) {
+	  MG_REG(FLASH_BASE2 + FLASH_KEYR) = 0x45670123;
+	  MG_REG(FLASH_BASE2 + FLASH_KEYR) = 0xcdef89ab;
+  }
+  if (MG_REG(FLASH_BASE1 + FLASH_OPTCR) & MG_BIT(0)) {
+	  MG_REG(FLASH_BASE1 + FLASH_OPTKEYR) = 0x08192a3b;  // opt reg is "shared"
+	  MG_REG(FLASH_BASE1 + FLASH_OPTKEYR) = 0x4c5d6e7f;  // thus unlock once
   }
 }
 

src/sock.c

@@ -449,6 +449,7 @@ void mg_connect_resolved(struct mg_connection *c) {
     if (rc == 0) {                       // Success
       setlocaddr(FD(c), &c->loc);
       mg_call(c, MG_EV_CONNECT, NULL);   // Send MG_EV_CONNECT to the user
+      if (c->is_tls_hs) mg_tls_handshake(c);
       if (!c->is_tls_hs) c->is_tls = 0;  // user did not call mg_tls_init()
     } else if (MG_SOCK_PENDING(rc)) {    // Need to wait for TCP handshake
       MG_DEBUG(("%lu %ld -> %M pend", c->id, c->fd, mg_print_ip_port, &c->rem));
@@ -465,6 +466,14 @@ static MG_SOCKET_TYPE raccept(MG_SOCKET_TYPE sock, union usa *usa,
   do {
     memset(usa, 0, sizeof(*usa));
     fd = accept(sock, &usa->sa, len);
+#if MG_ENABLE_FREERTOS_TCP
+    // FreeRTOS_accept() returns NULL to mean "no pending connection",
+    // therefore we avoid retrying it forever on non-blocking listeners
+    if (fd == NULL) {
+      fd = MG_INVALID_SOCKET;
+      break;
+    }
+#endif
   } while (MG_SOCK_INTR(fd));
   return fd;
 }

src/tls.h

@@ -87,6 +87,12 @@ void mg_tls_ctx_init(struct mg_mgr *);
 void mg_tls_ctx_free(struct mg_mgr *);
 #define MG_IS_DER(buf) (((uint8_t *) (buf))[0] == 0x30)  // DER begins with 0x30
 
+#if MG_TLS == MG_TLS_BUILTIN
+// Extracts a 32-byte P-256 private scalar from EC PRIVATE KEY or PKCS#8 PRIVATE
+// KEY input. Accepts PEM or DER. Returns key size, or 0 on error.
+size_t mg_uecc_parse_private_key(struct mg_str key, uint8_t *buf, size_t len);
+#endif
+
 // Low-level IO primitives used by TLS layer
 enum { MG_IO_ERR = -1, MG_IO_WAIT = -2 };
 long mg_io_send(struct mg_connection *c, const void *buf, size_t len);

src/tls_aes128.c

@@ -22,6 +22,7 @@
 
 #include "arch.h"
 #include "tls.h"
+#include "util.h"
 #if MG_TLS == MG_TLS_BUILTIN
 /******************************************************************************/
 #define AES_DECRYPTION 1  // whether AES decryption is supported
@@ -1061,10 +1062,9 @@ int gcm_crypt_and_tag(
                                     prepare the gcm context with the keying material, we simply
                                     invoke each of the three GCM sub-functions in turn...
                                  */
-  gcm_start(ctx, mode, iv, iv_len, add, add_len);
-  gcm_update(ctx, length, input, output);
-  gcm_finish(ctx, tag, tag_len);
-  return (0);
+  if (gcm_start(ctx, mode, iv, iv_len, add, add_len) != 0) return -1;
+  if (gcm_update(ctx, length, input, output) != 0) return -1;
+  return gcm_finish(ctx, tag, tag_len);
 }
 
 /******************************************************************************
@@ -1116,8 +1116,6 @@ int mg_aes_gcm_decrypt(unsigned char *output, const unsigned char *input,
   int ret = 0;      // our return value
   gcm_context ctx;  // includes the AES context structure
   unsigned char computed_tag[16];
-  size_t i;
-  int diff = 0;
 
   if (tag_len > sizeof(computed_tag)) return -1;
 
@@ -1128,9 +1126,7 @@ int mg_aes_gcm_decrypt(unsigned char *output, const unsigned char *input,
 
   gcm_zero_ctx(&ctx);
 
-  // compare tags
-  for (i = 0; i < tag_len; i++) diff |= computed_tag[i] ^ tag[i];
-  if (diff != 0) ret = -1;
+  if (!mg_memeq(computed_tag, tag, tag_len)) ret = -1;
 
   return (ret);
 }

src/tls_builtin.c

@@ -112,6 +112,8 @@ struct tls_data {
   bool skip_verification;    // do not perform checks on server certificate
   bool cert_requested;       // client received a CertificateRequest
   bool is_twoway;            // server is configured to authenticate clients
+  bool is_sntp_pending;      // TLS handshake is waiting for wall-clock time
+  struct mg_connection *timec;  // SNTP connection for wall-clock time
   struct mg_str cert_der;    // certificate in DER format
   struct mg_str ca_der;      // current CA certificate
   struct mg_str *ca_bundle_der; // bundle of CA certificates
@@ -192,16 +194,14 @@ static int mg_der_to_tlv(uint8_t *der, size_t dersz, struct mg_der_tlv *tlv) {
   if (tlv->len > 0x7f) {  // long-form length
     uint32_t i;
     n = tlv->len - 0x80;
-    if (n > 4 || dersz < (2 + n)) return -1;
+    if (n == 0 || n > 4 || dersz < (2 + n)) return -1;
     tlv->len = 0;
     for (i = 0; i < n; i++) {
       tlv->len = (tlv->len << 8) | der[2 + i];
     }
-    if (n > (dersz - 2)) return -1;
     tlv->value += n;
-  } else {
-    if (der + dersz < tlv->value + tlv->len) return -1;
   }
+  if (tlv->len > dersz - (size_t) (tlv->value - der)) return -1;
   return (int) n;
 }
 
@@ -557,7 +557,7 @@ static int mg_tls_recv_record(struct mg_connection *c) {
 
   msgsz = MG_LOAD_BE16(rio->buf + 3);
   msg = rio->buf + 5;
-  if (msgsz < 16) {
+  if (msgsz < 17) {
     mg_error(c, "wrong size");
     return -1;
   }
@@ -1319,6 +1319,7 @@ static int mg_tls_client_recv_hello(struct mg_connection *c) {
 
   if (rio->len < 5 + 39 + 32 + 3 + 2) goto fail;
   msgsz = MG_LOAD_BE16(rio->buf + 3);
+  if (msgsz > rio->len - 5) goto fail;
   mg_sha256_update(&tls->sha256, rio->buf + 5, msgsz);
 
   ext_len = MG_LOAD_BE16(rio->buf + 5 + 39 + 32 + 3);
@@ -1404,8 +1405,7 @@ static void mg_der_debug_cert_name(const char *name, struct mg_der_tlv *tlv) {
 }
 
 static uint64_t asnt2t(uint8_t *v, uint8_t type) {
-  unsigned int y, mo, d, h, mi, ss, ly;
-  uint16_t dm[12] = {0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334};
+  unsigned int y, mo, d, h, mi, ss;
   y = 10U * (*v++ - '0'), y += (*v++ - '0');
   if (type == 0x17) {       // UTCTime, RFC-5280 4.1.2.5.1 YYMMDDHHMMSSZ
     if (y >= 50) return (uint64_t) 0;  // 19YY is in the past
@@ -1413,17 +1413,13 @@ static uint64_t asnt2t(uint8_t *v, uint8_t type) {
   } else {  // GeneralizedTime, RFC-5280 4.1.2.5.2 YYYYMMDDHHMMSSZ
     y *= 100U, y += 10U * (*v++ - '0'), y += (*v++ - '0');
   }
-  y -= 1900;
   mo = 10U * (*v++ - '0'), mo += (*v++ - '0');
   d = 10U * (*v++ - '0'), d += (*v++ - '0');
   h = 10U * (*v++ - '0'), h += (*v++ - '0');
   mi = 10U * (*v++ - '0'), mi += (*v++ - '0');
   ss = 10U * (*v++ - '0'), ss += (*v++ - '0');
   if (*v != 'Z') return 0; // invalid
-  ly = (mo > 2) ? y + 1 : y;
-  return (uint64_t) ss + 60U * mi + 3600U * h + 86400U * (dm[mo - 1] + d - 1) +
-         31536000U * (y - 70) + 86400U * ((ly - 69) / 4U) -
-         86400U * ((ly - 1) / 100U) + 86400U * ((ly + 299) / 400U);
+  return mg_timegm(y, mo, d, h, mi, ss);
 }
 
 static int mg_tls_parse_cert_der(void *buf, size_t dersz,
@@ -1704,7 +1700,6 @@ static int mg_tls_verify_cert_signature(const struct mg_tls_cert *cert,
       return 0;
     }
   } else {
-    uint8_t r;
     const uint8_t *n;
     size_t nlen;
     uint8_t sig2[512];  // 4096 bits
@@ -1724,15 +1719,7 @@ static int mg_tls_verify_cert_signature(const struct mg_tls_cert *cert,
       return 0;
     }
 
-    r = 0;
-    {
-      const uint8_t *p, *q;
-      size_t i;
-      p = sig2 + nlen - cert->tbshashsz;
-      q = cert->tbshash;
-      for (i = 0; i < cert->tbshashsz; i++) r |= (uint8_t)(*p++ ^ *q++);
-    }
-    return r == 0;
+    return mg_rsa_pkcs_verify(sig2, nlen, cert->tbshash, cert->tbshashsz);
   }
 }
 
@@ -1903,7 +1890,11 @@ static int mg_tls_recv_cert(struct mg_connection *c, bool is_client) {
         mg_error(c, r < 0 ? "failed to parse CA bundle"
                           : "failed to find issuing CA in bundle");
         return -1;
-      }  // else r > 0 => issuer found
+      } else if (!ca.is_ca ||  // candidate issuer found
+                 !mg_tls_verify_cert_signature(&certs[certnum - 1], &ca)) {
+        mg_error(c, "failed to verify CA");
+        return -1;
+      }  // issuer verified. NOTE(): may fail if two diff CAs share a CN
       MG_VERBOSE(("CA serial: %M", mg_print_hex, ca.sn.len, ca.sn.buf));
     }
     if (!found_ca && tls->ca_der.len > 0) {  // single cert or server
@@ -2159,6 +2150,7 @@ void mg_tls_handshake(struct mg_connection *c) {
   long n;
   bool res;
   if (c->is_closing) return;  // we don't clear rx buf, so ignore what's left
+  if (tls->is_sntp_pending) return;
   if (c->is_client) {
     // will clear is_hs when sending last chunk
     res = mg_tls_client_handshake(c);
@@ -2198,7 +2190,7 @@ static int mg_rsa_parse_der_int(const uint8_t **p, const uint8_t *end,
     // Long form length
     uint8_t len_bytes = len & 0x7F;
     MG_VERBOSE(("DER INT: long form, %d length bytes", len_bytes));
-    if (end - *p < len_bytes) {
+    if (len_bytes == 0 || len_bytes > 4 || (size_t) (end - *p) < len_bytes) {
       MG_VERBOSE(("DER INT: not enough bytes for length"));
       return -1;
     }
@@ -2211,7 +2203,7 @@ static int mg_rsa_parse_der_int(const uint8_t **p, const uint8_t *end,
 
   MG_VERBOSE(("DER INT: length=%u, remaining=%d", len, (int) (end - *p)));
 
-  if (end - *p < (long) len) {
+  if ((size_t) (end - *p) < len) {
     MG_VERBOSE(("DER INT: length exceeds remaining bytes"));
     return -1;
   }
@@ -2253,12 +2245,12 @@ static int mg_parse_ec_private_key(const uint8_t *der, size_t dersz,
     return -1;
   }
 
-  if (mg_der_next(&root, &version) < 0 || version.type != 0x02) {
+  if (mg_der_next(&root, &version) <= 0 || version.type != 0x02) {
     MG_ERROR(("EC private key: invalid version"));
     return -1;
   }
 
-  if (mg_der_next(&root, &private_key_octets) < 0 ||
+  if (mg_der_next(&root, &private_key_octets) <= 0 ||
       private_key_octets.type != 0x04) {
     MG_ERROR(("EC private key: invalid privateKey OCTET STRING"));
     return -1;
@@ -2312,7 +2304,7 @@ static int mg_rsa_parse_key(const uint8_t *der, size_t dersz,
     // Long form length
     uint8_t i, len_bytes = seq_len & 0x7F;
     MG_VERBOSE(("Long form length: %d bytes", len_bytes));
-    if (end - p < len_bytes) {
+    if (len_bytes == 0 || len_bytes > 4 || (size_t) (end - p) < len_bytes) {
       MG_ERROR(("Not enough bytes for long form length"));
       return -1;
     }
@@ -2326,7 +2318,7 @@ static int mg_rsa_parse_key(const uint8_t *der, size_t dersz,
   MG_VERBOSE(
       ("SEQUENCE length: %u, total DER size: %u", seq_len, (unsigned) dersz));
 
-  if (end - p < (long) seq_len) {
+  if ((size_t) (end - p) < seq_len) {
     MG_ERROR(("SEQUENCE length exceeds buffer"));
     return -1;
   }
@@ -2334,7 +2326,9 @@ static int mg_rsa_parse_key(const uint8_t *der, size_t dersz,
 
   // Parse version (should be 0)
   MG_VERBOSE(("Before version: offset=%d, bytes: %02x %02x %02x %02x",
-              (int) (p - der), p[0], p[1], p[2], p[3]));
+              (int) (p - der), p < end ? p[0] : 0xFF,
+              p + 1 < end ? p[1] : 0xFF, p + 2 < end ? p[2] : 0xFF,
+              p + 3 < end ? p[3] : 0xFF));
   if (mg_rsa_parse_der_int(&p, end, &version) < 0) {
     MG_ERROR(("Failed to parse version"));
     return -1;
@@ -2345,7 +2339,10 @@ static int mg_rsa_parse_key(const uint8_t *der, size_t dersz,
 
   // Parse the 8 components: n, e, d, p, q, dP, dQ, qInv
   MG_VERBOSE(("Before n: offset=%d, bytes: %02x %02x %02x %02x %02x %02x",
-              (int) (p - der), p[0], p[1], p[2], p[3], p[4], p[5]));
+              (int) (p - der), p < end ? p[0] : 0xFF,
+              p + 1 < end ? p[1] : 0xFF, p + 2 < end ? p[2] : 0xFF,
+              p + 3 < end ? p[3] : 0xFF, p + 4 < end ? p[4] : 0xFF,
+              p + 5 < end ? p[5] : 0xFF));
   if (mg_rsa_parse_der_int(&p, end, &key->n) < 0) {
     MG_ERROR(("Failed to parse n (modulus)"));
     return -1;
@@ -2353,10 +2350,14 @@ static int mg_rsa_parse_key(const uint8_t *der, size_t dersz,
   MG_VERBOSE(("Parsed n: %d bytes, offset now=%d, consumed=%d bytes total",
               (int) key->n.len, (int) (p - der), (int) (p - der)));
   MG_VERBOSE(("  First 8 bytes of n: %02x %02x %02x %02x %02x %02x %02x %02x",
-              (unsigned char) key->n.buf[0], (unsigned char) key->n.buf[1],
-              (unsigned char) key->n.buf[2], (unsigned char) key->n.buf[3],
-              (unsigned char) key->n.buf[4], (unsigned char) key->n.buf[5],
-              (unsigned char) key->n.buf[6], (unsigned char) key->n.buf[7]));
+              key->n.len > 0 ? (unsigned char) key->n.buf[0] : 0xFF,
+              key->n.len > 1 ? (unsigned char) key->n.buf[1] : 0xFF,
+              key->n.len > 2 ? (unsigned char) key->n.buf[2] : 0xFF,
+              key->n.len > 3 ? (unsigned char) key->n.buf[3] : 0xFF,
+              key->n.len > 4 ? (unsigned char) key->n.buf[4] : 0xFF,
+              key->n.len > 5 ? (unsigned char) key->n.buf[5] : 0xFF,
+              key->n.len > 6 ? (unsigned char) key->n.buf[6] : 0xFF,
+              key->n.len > 7 ? (unsigned char) key->n.buf[7] : 0xFF));
   MG_VERBOSE(("  Next bytes after n: %02x %02x %02x %02x %02x %02x",
               p < end ? p[0] : 0xFF, p + 1 < end ? p[1] : 0xFF,
               p + 2 < end ? p[2] : 0xFF, p + 3 < end ? p[3] : 0xFF,
@@ -2410,7 +2411,7 @@ static int mg_rsa_parse_key(const uint8_t *der, size_t dersz,
 //   parameters ANY OPTIONAL
 // }
 static int mg_parse_pkcs8_key(const uint8_t *der, size_t dersz,
-                              struct tls_data *tls) {
+                              struct mg_rsa_key *rsa, uint8_t *ec_key) {
   struct mg_der_tlv root, version, alg_id, private_key_octets;
   struct mg_der_tlv alg_oid, alg_params;
 
@@ -2419,22 +2420,22 @@ static int mg_parse_pkcs8_key(const uint8_t *der, size_t dersz,
     return -1;
   }
 
-  if (mg_der_next(&root, &version) < 0 || version.type != 0x02) {
+  if (mg_der_next(&root, &version) <= 0 || version.type != 0x02) {
     MG_ERROR(("PKCS#8: invalid version"));
     return -1;
   }
 
-  if (mg_der_next(&root, &alg_id) < 0 || alg_id.type != 0x30) {
+  if (mg_der_next(&root, &alg_id) <= 0 || alg_id.type != 0x30) {
     MG_ERROR(("PKCS#8: invalid AlgorithmIdentifier SEQUENCE"));
     return -1;
   }
 
-  if (mg_der_next(&alg_id, &alg_oid) < 0 || alg_oid.type != 0x06) {
+  if (mg_der_next(&alg_id, &alg_oid) <= 0 || alg_oid.type != 0x06) {
     MG_ERROR(("PKCS#8: invalid algorithm OID"));
     return -1;
   }
 
-  if (mg_der_next(&root, &private_key_octets) < 0 ||
+  if (mg_der_next(&root, &private_key_octets) <= 0 ||
       private_key_octets.type != 0x04) {
     MG_ERROR(("PKCS#8: invalid privateKey OCTET STRING"));
     return -1;
@@ -2443,18 +2444,20 @@ static int mg_parse_pkcs8_key(const uint8_t *der, size_t dersz,
   if (alg_oid.len == sizeof(mg_rsa_oid) &&
       memcmp(alg_oid.value, mg_rsa_oid, sizeof(mg_rsa_oid)) == 0) {
     struct mg_rsa_key rsa_key;
+    if (rsa == NULL) return -1;
     if (mg_rsa_parse_key(private_key_octets.value, private_key_octets.len,
                          &rsa_key) < 0) {
       MG_ERROR(("PKCS#8: failed to parse inner RSA key"));
       return -1;
     }
-    tls->rsa = rsa_key;
+    *rsa = rsa_key;
     return 0;
 
   } else if (alg_oid.len == sizeof(mg_ec_public_key_oid) &&
              memcmp(alg_oid.value, mg_ec_public_key_oid,
                     sizeof(mg_ec_public_key_oid)) == 0) {
-    if (mg_der_next(&alg_id, &alg_params) < 0 || alg_params.type != 0x06) {
+    if (ec_key == NULL) return -1;
+    if (mg_der_next(&alg_id, &alg_params) <= 0 || alg_params.type != 0x06) {
       MG_ERROR(("PKCS#8: invalid EC parameters OID"));
       return -1;
     }
@@ -2467,7 +2470,7 @@ static int mg_parse_pkcs8_key(const uint8_t *der, size_t dersz,
     }
 
     return mg_parse_ec_private_key(private_key_octets.value,
-                                   private_key_octets.len, tls->ec_key);
+                                   private_key_octets.len, ec_key);
 
   } else {
     MG_ERROR(("PKCS#8: unsupported algorithm"));
@@ -2572,6 +2575,38 @@ static int mg_parse_pem_certs(const struct mg_str pem, struct mg_str **ders) {
   return count;
 }
 
+size_t mg_uecc_parse_private_key(struct mg_str key, uint8_t *buf, size_t len) {
+  struct mg_str der = mg_str_n(NULL, 0);
+  size_t n = 0;
+  if (buf == NULL || len < 32) return 0;
+  // current mg_parse_ec_private_key() only handles 32-byte keys
+  if (mg_parse_pem(key, mg_str_s("EC PRIVATE KEY"), &der) == 0) {
+    if (mg_parse_ec_private_key((uint8_t *) der.buf, der.len, buf) == 0) n = 32;
+  } else if (mg_parse_pem(key, mg_str_s("PRIVATE KEY"), &der) == 0) {
+    if (mg_parse_pkcs8_key((uint8_t *) der.buf, der.len, NULL, buf) == 0) n = 32;
+  }
+  mg_free((void *) der.buf);
+  return n;
+}
+
+static void sync_time_cancel(struct mg_connection *c) {
+  c->fn = NULL;
+  c->is_closing = 1;
+}
+
+static void sync_time_cb(struct mg_connection *c, int ev, void *ev_data) {
+  if (ev == MG_EV_SNTP_TIME || (ev == MG_EV_CLOSE)) {
+    struct mg_connection *tlsc = (struct mg_connection *) c->fn_data;
+    struct tls_data *tls = (struct tls_data *) tlsc->tls;
+    sync_time_cancel(c);  // c = tls->timec
+    tls->timec = NULL;
+    tls->is_sntp_pending = false;
+    if (ev == MG_EV_SNTP_TIME) mg_tls_handshake(tlsc);
+    if (ev == MG_EV_CLOSE) mg_error(tlsc, "time sync failed");
+  }
+  (void) ev_data;
+}
+
 void mg_tls_init(struct mg_connection *c, const struct mg_tls_opts *opts) {
   struct mg_str key;
   struct tls_data *tls =
@@ -2617,7 +2652,7 @@ void mg_tls_init(struct mg_connection *c, const struct mg_tls_opts *opts) {
     } else { // parse again for a possible DER (or a truncated begin string)
       if (mg_parse_pem(opts->ca, mg_str_s("CERTIFICATE"), &tls->ca_der) < 0) {
         MG_ERROR(("Failed to load CA certificate"));
-        return;
+        goto xit;
       }
     } // ca_bundle_len != 0 && ca_der.len = 0 => bundle
     if (!c->is_client) tls->is_twoway = true;  // server + CA: two-way auth
@@ -2625,7 +2660,7 @@ void mg_tls_init(struct mg_connection *c, const struct mg_tls_opts *opts) {
 
   if (opts->cert.buf == NULL) {
     MG_VERBOSE(("No certificate provided"));
-    return;
+    goto xit;
   }
 
   // parse PEM or DER certificate
@@ -2696,7 +2731,8 @@ void mg_tls_init(struct mg_connection *c, const struct mg_tls_opts *opts) {
     // Copy parsed RSA key components to tls->rsa for signing operations
     tls->rsa = rsa_key;
   } else if (mg_parse_pem(opts->key, mg_str_s("PRIVATE KEY"), &key) == 0) {
-    if (mg_parse_pkcs8_key((const uint8_t *) key.buf, key.len, tls) == 0) {
+    if (mg_parse_pkcs8_key((const uint8_t *) key.buf, key.len, &tls->rsa,
+                           tls->ec_key) == 0) {
       if (tls->rsa.n.len > 0) {
         tls->rsa_key_der = key;
         MG_INFO(("Parsed PKCS#8 RSA private key: %d bytes", (int) key.len));
@@ -2712,6 +2748,19 @@ void mg_tls_init(struct mg_connection *c, const struct mg_tls_opts *opts) {
   } else {
     mg_error(
         c, "Expected EC PRIVATE KEY, RSA PRIVATE KEY, or PRIVATE KEY (PKCS#8)");
+    return;
+  }
+xit:
+  if (mg_boot_timestamp_ms == 0 && !tls->skip_verification &&
+      (tls->ca_bundle_len > 0 || tls->ca_der.len > 0)) {
+    struct mg_connection *timec;
+    timec = mg_sntp_connect(c->mgr, NULL, sync_time_cb, c);
+    if (timec == NULL) {
+      mg_error(c, "time sync failed");
+      return;
+    }
+    tls->is_sntp_pending = true;
+    tls->timec = timec;
   }
 }
 
@@ -2719,6 +2768,10 @@ void mg_tls_free(struct mg_connection *c) {
   struct tls_data *tls = (struct tls_data *) c->tls;
   size_t i;
   if (tls != NULL) {
+    if (tls->timec != NULL) {
+      sync_time_cancel(tls->timec);
+      tls->timec = NULL;
+    }
     mg_iobuf_free(&tls->send);
     if (tls->chain_der != NULL) {
       for (i = 0; i < tls->chain_len; i++) {

src/tls_chacha20.c

@@ -6,8 +6,9 @@
 
 #include "tls_chacha20.h"
 #include "tls.h"
+#include "util.h"
 
-#if MG_TLS == MG_TLS_BUILTIN
+#if MG_TLS == MG_TLS_BUILTIN && MG_ENABLE_CHACHA20
 // ******* BEGIN: chacha-portable/chacha-portable.h ********
 
 #if !defined(__cplusplus) && !defined(_MSC_VER) && \
@@ -1336,8 +1337,6 @@ PORTABLE_8439_DECL size_t mg_chacha20_poly1305_decrypt(
   // first we calculate the mac and see if it lines up, only then do we decrypt
   size_t actual_size = cipher_text_size - RFC_8439_TAG_SIZE;
   uint8_t computed_mac[RFC_8439_TAG_SIZE];
-  int diff = 0;
-  size_t i;
   if (MG_OVERLAPPING(plain_text, actual_size, cipher_text, cipher_text_size)) {
     return (size_t) -1;
   }
@@ -1345,10 +1344,8 @@ PORTABLE_8439_DECL size_t mg_chacha20_poly1305_decrypt(
   poly1305_calculate_mac(computed_mac, cipher_text, actual_size, key, nonce, ad,
                          ad_size);
 
-  // compare tags
-  for (i = 0; i < RFC_8439_TAG_SIZE; i++)
-    diff |= computed_mac[i] ^ cipher_text[actual_size + i];
-  if (diff != 0) return (size_t) -1;
+  if (!mg_memeq(computed_mac, cipher_text + actual_size, RFC_8439_TAG_SIZE))
+    return (size_t) -1;
 
   chacha20_xor_stream(plain_text, cipher_text, actual_size, key, nonce, 1);
   return actual_size;

src/tls_chacha20.h

@@ -8,7 +8,7 @@
 #include "config.h"
 #include "tls.h"
 
-#if MG_TLS == MG_TLS_BUILTIN
+#if MG_TLS == MG_TLS_BUILTIN && MG_ENABLE_CHACHA20
 #ifndef __PORTABLE_8439_H
 #define __PORTABLE_8439_H
 #if defined(__cplusplus)

src/tls_mbed.c

@@ -92,6 +92,11 @@ void mg_tls_handshake(struct mg_connection *c) {
   struct mg_tls *tls = (struct mg_tls *) c->tls;
   int rc = mbedtls_ssl_handshake(&tls->ssl);
   if (rc == 0) {  // Success
+    if (tls->check_name && (mbedtls_ssl_get_verify_result(&tls->ssl) &
+                            MBEDTLS_X509_BADCERT_CN_MISMATCH)) {
+      mg_error(c, "failed to verify hostname");
+      return;
+    } // ignore MBEDTLS_X509_BADCERT_NOT_TRUSTED, no CA cert given
     MG_DEBUG(("%lu success", c->id));
     c->is_tls_hs = 0;
     mg_call(c, MG_EV_TLS_HS, NULL);
@@ -113,6 +118,7 @@ static void debug_cb(void *c, int lev, const char *s, int n, const char *s2) {
 void mg_tls_init(struct mg_connection *c, const struct mg_tls_opts *opts) {
   struct mg_tls *tls = (struct mg_tls *) mg_calloc(1, sizeof(*tls));
   int rc = 0;
+  bool check_name = false;
   c->tls = tls;
   if (c->tls == NULL) {
     mg_error(c, "TLS OOM");
@@ -143,24 +149,30 @@ void mg_tls_init(struct mg_connection *c, const struct mg_tls_opts *opts) {
   mbedtls_ssl_conf_rng(&tls->conf, mg_mbed_rng, c);
 #endif
 
+  if (c->is_client && opts->name.buf != NULL && opts->name.len > 0 &&
+      opts->name.buf[0] != '\0') {
+    char *host = mg_mprintf("%.*s", opts->name.len, opts->name.buf);
+    mbedtls_ssl_set_hostname(&tls->ssl, host);
+#if !defined(MBEDTLS_VERSION_NUMBER) || MBEDTLS_VERSION_NUMBER < 0x03030000 || \
+    MBEDTLS_VERSION_NUMBER >= 0x04000000
+    // NOTE: MBEDTLS_SSL_VERIFY_OPTIONAL is not supported for TLS1.3 on client
+    // side See https://github.com/Mbed-TLS/mbedtls/issues/7075
+    check_name = true;
+#endif
+    MG_DEBUG(("%lu hostname verification: %s", c->id, host));
+    mg_free(host);
+  } else {
+    MG_DEBUG(("%lu skipping hostname verification", c->id));
+    mbedtls_ssl_set_hostname(&tls->ssl, NULL);
+  }
   if (opts->ca.len == 0 || mg_strcmp(opts->ca, mg_str("*")) == 0) {
-    // NOTE: MBEDTLS_SSL_VERIFY_NONE is not supported for TLS1.3 on client side
-    // See https://github.com/Mbed-TLS/mbedtls/issues/7075
-    mbedtls_ssl_conf_authmode(&tls->conf, MBEDTLS_SSL_VERIFY_NONE);
+    mbedtls_ssl_conf_authmode(&tls->conf, check_name  // see set comment above
+                                              ? MBEDTLS_SSL_VERIFY_OPTIONAL
+                                              : MBEDTLS_SSL_VERIFY_NONE);
+    tls->check_name = check_name; // host name set but no CA cert given
   } else {
     if (mg_load_cert(opts->ca, &tls->ca) == false) goto fail;
     mbedtls_ssl_conf_ca_chain(&tls->conf, &tls->ca, NULL);
-    if (c->is_client) {
-      if (opts->name.buf != NULL && opts->name.buf[0] != '\0') {
-        char *host = mg_mprintf("%.*s", opts->name.len, opts->name.buf);
-        mbedtls_ssl_set_hostname(&tls->ssl, host);
-        MG_DEBUG(("%lu hostname verification: %s", c->id, host));
-        mg_free(host);
-      } else {
-        MG_DEBUG(("%lu skipping hostname verification", c->id));
-        mbedtls_ssl_set_hostname(&tls->ssl, NULL);
-      }
-    }
     mbedtls_ssl_conf_authmode(&tls->conf, MBEDTLS_SSL_VERIFY_REQUIRED);
   }
   if (!mg_load_cert(opts->cert, &tls->cert)) goto fail;

src/tls_mbed.h

@@ -24,12 +24,13 @@ struct mg_tls {
   mbedtls_x509_crt cert;    // Parsed certificate
   mbedtls_pk_context pk;    // Private key context
   mbedtls_ssl_context ssl;  // SSL/TLS context
-  mbedtls_ssl_config conf;  // SSL-TLS config
+  mbedtls_ssl_config conf;  // SSL/TLS config
 #ifdef MBEDTLS_SSL_SESSION_TICKETS
   mbedtls_ssl_ticket_context ticket;  // Session tickets context
 #endif
   // https://github.com/Mbed-TLS/mbedtls/blob/3b3c652d/include/mbedtls/ssl.h#L5071C18-L5076C29
   unsigned char *throttled_buf;  // see #3074
   size_t throttled_len;
+  bool check_name;  // set when hostname was set, but no CA certificate given
 };
 #endif

src/tls_openssl.c

@@ -141,6 +141,7 @@ void mg_tls_free(struct mg_connection *c) {
   SSL_free(tls->ssl);
   SSL_CTX_free(tls->ctx);
   BIO_meth_free(tls->bm);
+  mg_free(tls->name);
   mg_free(tls);
   c->tls = NULL;
 }
@@ -148,6 +149,7 @@ void mg_tls_free(struct mg_connection *c) {
 void mg_tls_init(struct mg_connection *c, const struct mg_tls_opts *opts) {
   struct mg_tls *tls = (struct mg_tls *) mg_calloc(1, sizeof(*tls));
   const char *id = "mongoose";
+  bool check_name = false;
   static unsigned char s_initialised = 0;
   BIO *bio = NULL;
   int rc;
@@ -189,6 +191,14 @@ void mg_tls_init(struct mg_connection *c, const struct mg_tls_opts *opts) {
   SSL_set_options(tls->ssl, SSL_OP_CIPHER_SERVER_PREFERENCE);
 #endif
 
+if (c->is_client && opts->name.buf != NULL && opts->name.len > 0 && opts->name.buf[0] != '\0') {
+  tls->name = mg_mprintf("%.*s", (int) opts->name.len, opts->name.buf);
+  if (tls->name == NULL) {
+    mg_error(c, "TLS OOM");
+    goto fail;
+  }
+  check_name = true;
+}
 #if MG_TLS == MG_TLS_WOLFSSL && !defined(OPENSSL_COMPATIBLE_DEFAULTS)
   if (opts->ca.len == 0 || mg_strcmp(opts->ca, mg_str("*")) == 0) {
     // Older versions require that either the CA is loaded or SSL_VERIFY_NONE
@@ -197,7 +207,7 @@ void mg_tls_init(struct mg_connection *c, const struct mg_tls_opts *opts) {
   }
 #endif
 
-  if (opts->ca.buf != NULL && opts->ca.buf[0] != '\0') {
+  if (opts->ca.buf != NULL && opts->ca.len > 0 && opts->ca.buf[0] != '\0') {
     SSL_set_verify(tls->ssl, SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT,
                    NULL);
 #if MG_TLS == MG_TLS_WOLFSSL
@@ -219,6 +229,8 @@ void mg_tls_init(struct mg_connection *c, const struct mg_tls_opts *opts) {
       goto fail;
     }
 #endif
+  } else {
+    tls->check_name = check_name; // host name set but no CA cert given
   }
 
   if (opts->cert.buf != NULL && opts->cert.buf[0] != '\0') {
@@ -243,15 +255,13 @@ void mg_tls_init(struct mg_connection *c, const struct mg_tls_opts *opts) {
   (void) SSL_set_ecdh_auto(tls->ssl, 1);
 #endif
 #if OPENSSL_VERSION_NUMBER >= 0x10100000L
-  if (opts->name.len > 0) {
-    char *s = mg_mprintf("%.*s", (int) opts->name.len, opts->name.buf);
+  if (tls->name != NULL) {
 #if MG_TLS != MG_TLS_WOLFSSL || LIBWOLFSSL_VERSION_HEX >= 0x05005002
-    SSL_set1_host(tls->ssl, s);
+    SSL_set1_host(tls->ssl, tls->name);
 #else
-    X509_VERIFY_PARAM_set1_host(SSL_get0_param(tls->ssl), s, 0);
+    X509_VERIFY_PARAM_set1_host(SSL_get0_param(tls->ssl), tls->name, 0);
 #endif
-    SSL_set_tlsext_host_name(tls->ssl, s);
-    mg_free(s);
+    SSL_set_tlsext_host_name(tls->ssl, tls->name);
   }
 #endif
 #if MG_TLS == MG_TLS_WOLFSSL
@@ -279,6 +289,16 @@ void mg_tls_handshake(struct mg_connection *c) {
   struct mg_tls *tls = (struct mg_tls *) c->tls;
   int rc = c->is_client ? SSL_connect(tls->ssl) : SSL_accept(tls->ssl);
   if (rc == 1) {
+    if (tls->check_name) {  // host name set but no CA cert given
+      X509 *cert = SSL_get_peer_certificate(tls->ssl);
+      bool ok =
+          cert != NULL && X509_check_host(cert, tls->name, 0, 0, NULL) == 1;
+      X509_free(cert);
+      if (!ok) {
+        mg_error(c, "failed to verify hostname");
+        return;
+      }
+    }
     MG_DEBUG(("%lu success", c->id));
     c->is_tls_hs = 0;
     mg_call(c, MG_EV_TLS_HS, NULL);
@@ -295,7 +315,12 @@ size_t mg_tls_pending(struct mg_connection *c) {
 
 long mg_tls_recv(struct mg_connection *c, void *buf, size_t len) {
   struct mg_tls *tls = (struct mg_tls *) c->tls;
-  int n = SSL_read(tls->ssl, buf, (int) len);
+  int n;
+#if MG_TLS == MG_TLS_WOLFSSL
+  uint8_t dummy; // WolfSSL requires destination != NULL
+  if (buf == NULL && len == 0) buf = &dummy;
+#endif
+  n = SSL_read(tls->ssl, buf, (int) len);
   if (!c->is_tls_hs && (buf == NULL || len == 0) && n == 0) return 0;  // MIP
   if (n < 0 && mg_tls_err(c, tls, n) == 0) return MG_IO_WAIT;
   if (n <= 0) return MG_IO_ERR;

src/tls_openssl.h

@@ -4,10 +4,13 @@
 
 #include <openssl/err.h>
 #include <openssl/ssl.h>
+#include <openssl/x509v3.h>
 
 struct mg_tls {
   BIO_METHOD *bm;
   SSL_CTX *ctx;
   SSL *ssl;
+  char *name;       // matching hostname
+  bool check_name;  // set when hostname was set, but no CA certificate given
 };
 #endif

src/tls_rsa.c

@@ -950,4 +950,41 @@ bool mg_rsa_verify(const uint8_t *em, size_t nlen, const uint8_t *mhash) {
   return pss_verify_sha256(em, nlen, mhash);
 }
 
+// Full RSASSA-PKCS1-v1_5-VERIFY for rsa_pkcs1_sha256/sha384 (RFC 8017 9.2)
+// em      - output of RSA public-key primitive (nlen bytes)
+// nlen    - modulus byte length
+// hash    - SHA-256 or SHA-384 of the certificate TBS data
+// hashlen - hash length, 32 for SHA-256 or 48 for SHA-384
+static bool pkcs1_v15_verify(const uint8_t *em, size_t nlen,
+                             const uint8_t *hash, size_t hashlen) {
+  static const uint8_t sha256_di[] = {
+      0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01,
+      0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04, 0x20};
+  static const uint8_t sha384_di[] = {
+      0x30, 0x41, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01,
+      0x65, 0x03, 0x04, 0x02, 0x02, 0x05, 0x00, 0x04, 0x30};
+  const uint8_t *di = hashlen == 32 ? sha256_di : sha384_di;
+  size_t disz = hashlen == 32 ? sizeof(sha256_di) : sizeof(sha384_di);
+  size_t pslen, i;
+  uint8_t bad = 0;
+
+  if (hashlen != 32 && hashlen != 48) return false;
+  if (nlen < 3 + 8 + disz + hashlen) return false;
+  pslen = nlen - 3 - disz - hashlen;
+
+  bad |= (uint8_t) (em[0] | (em[1] ^ 0x01));
+  for (i = 0; i < pslen; i++) bad |= (uint8_t) (em[2 + i] ^ 0xff);
+  bad |= em[2 + pslen];
+  for (i = 0; i < disz; i++) bad |= (uint8_t) (em[3 + pslen + i] ^ di[i]);
+  for (i = 0; i < hashlen; i++)
+    bad |= (uint8_t) (em[3 + pslen + disz + i] ^ hash[i]);
+
+  return bad == 0;
+}
+
+bool mg_rsa_pkcs_verify(const uint8_t *em, size_t nlen, const uint8_t *hash,
+                        size_t hashlen) {
+  return pkcs1_v15_verify(em, nlen, hash, hashlen);
+}
+
 #endif /* MG_TLS == MG_TLS_BUILTIN */

src/tls_rsa.h

@@ -10,5 +10,7 @@ int mg_rsa_crt_sign(const uint8_t *em, size_t em_len,
                     const uint8_t *q, size_t q_len,
                     const uint8_t *qInv, size_t qInv_len,
                     uint8_t *signature, size_t sig_len);
+bool mg_rsa_pkcs_verify(const uint8_t *em, size_t nlen, const uint8_t *hash,
+                        size_t hashlen);
 bool mg_rsa_verify(const uint8_t *em, size_t nlen, const uint8_t *mhash);
 #endif // TLS_RSA_H

src/tls_uecc.c

@@ -222,11 +222,7 @@ static cmpresult_t mg_uecc_vli_cmp_unsafe(const mg_uecc_word_t *left,
 #define asm_mmod_fast_secp256r1 0
 #endif
 
-#if defined(default_RNG_defined) && default_RNG_defined
-static MG_UECC_RNG_Function g_rng_function = &default_RNG;
-#else
-static MG_UECC_RNG_Function g_rng_function = 0;
-#endif
+static MG_UECC_RNG_Function g_rng_function = NULL;
 
 void mg_uecc_set_rng(MG_UECC_RNG_Function rng_function) {
   g_rng_function = rng_function;
@@ -2560,15 +2556,11 @@ MG_UECC_VLI_API int mg_uecc_generate_random_int(mg_uecc_word_t *random,
   mg_uecc_word_t tries;
   bitcount_t num_bits = mg_uecc_vli_numBits(top, num_words);
 
-  if (!g_rng_function) {
-    return 0;
-  }
-
   for (tries = 0; tries < MG_UECC_RNG_MAX_TRIES; ++tries) {
-    if (!g_rng_function((uint8_t *) random,
-                        (unsigned int) (num_words * MG_UECC_WORD_SIZE))) {
+    unsigned int len = (unsigned int) (num_words * MG_UECC_WORD_SIZE);
+    if (!(g_rng_function == NULL ? mg_random((uint8_t *) random, len)
+                                 : g_rng_function((uint8_t *) random, len)))
       return 0;
-    }
     random[num_words - 1] &=
         mask >> ((bitcount_t) (num_words * MG_UECC_WORD_SIZE * 8 - num_bits));
     if (!mg_uecc_vli_isZero(random, num_words) &&

src/tls_uecc.h

@@ -113,28 +113,28 @@ if 'dest' was filled with random data, or 0 if the random data could not be
 generated. The filled-in values should be either truly random, or from a
 cryptographically-secure PRNG.
 
-A correctly functioning RNG function must be set (using mg_uecc_set_rng())
-before calling mg_uecc_make_key() or mg_uecc_sign().
+A correctly functioning RNG is required before calling mg_uecc_make_key() or
+mg_uecc_sign().
 
 Setting a correctly functioning RNG function improves the resistance to
 side-channel attacks for mg_uecc_shared_secret() and
 mg_uecc_sign_deterministic().
-
-A correct RNG function is set by default when building for Windows, Linux, or OS
-X. If you are building on another POSIX-compliant system that supports
-/dev/random or /dev/urandom, you can define MG_UECC_POSIX to use the predefined
-RNG. For embedded platforms there is no predefined RNG function; you must
-provide your own.
 */
 typedef int (*MG_UECC_RNG_Function)(uint8_t *dest, unsigned size);
 
+// Mongoose: mg_uecc_make_key() and mg_uecc_sign() use mg_random() when no
+// explicit uECC RNG is installed. If mg_random() cannot provide a strong source,
+// those operations fail. Deterministic signing works without RNG, but only an
+// explicit uECC RNG enables its optional side-channel blinding.
+
 /* mg_uecc_set_rng() function.
 Set the function that will be used to generate random bytes. The RNG function
 should return 1 if the random data was generated, or 0 if the random data could
 not be generated.
 
-On platforms where there is no predefined RNG function (eg embedded platforms),
-this must be called before mg_uecc_make_key() or mg_uecc_sign() are used.
+Mongoose: this overrides the default mg_random() fallback used by
+mg_uecc_make_key() and mg_uecc_sign(). Do not call mg_uecc_set_rng() unless the
+application must provide its own cryptographic RNG.
 
 Inputs:
     rng_function - The function that will be used to generate random bytes.

src/util.c

@@ -9,6 +9,30 @@ void mg_bzero(volatile unsigned char *buf, size_t len) {
   }
 }
 
+uint64_t mg_timegm(unsigned int year, unsigned int month, unsigned int day,
+                   unsigned int hour, unsigned int min, unsigned int sec) {
+  static const uint16_t dm[12] = {0,   31,  59,  90,  120, 151,
+                                  181, 212, 243, 273, 304, 334};
+  const uint64_t day_secs = 86400;
+  const uint64_t year_secs = 31536000;
+  unsigned int y, ly;
+  if (year < 1970) return 0;
+  y = year - 1900;
+  ly = month > 2 ? y + 1 : y;
+  return (uint64_t) sec + 60 * min + 3600 * hour +
+         day_secs * (dm[month - 1] + day - 1) + year_secs * (y - 70) +
+         day_secs * ((ly - 69) / 4) - day_secs * ((ly - 1) / 100) +
+         day_secs * ((ly + 299) / 400);
+}
+
+bool mg_memeq(const void *a, const void *b, size_t n) {
+  const uint8_t *p = (const uint8_t *) a, *q = (const uint8_t *) b;
+  uint8_t r = 0;
+  size_t i;
+  for (i = 0; i < n; i++) r = (uint8_t) (r | (uint8_t) (p[i] ^ q[i]));
+  return r == 0;
+}
+
 #if MG_ENABLE_CUSTOM_RANDOM
 #else
 bool mg_random(void *buf, size_t len) {
@@ -104,6 +128,20 @@ uint32_t mg_crc32(uint32_t crc, const char *buf, size_t len) {
   return ~crc;
 }
 
+uint16_t mg_crc16(uint16_t crc, const char *buf, size_t len) {
+  static const uint16_t crclut[16] = {
+      // table for polynomial 0x8408 (reflected)
+      0x0000, 0x1081, 0x2102, 0x3183, 0x4204, 0x5285, 0x6306, 0x7387,
+      0x8408, 0x9489, 0xA50A, 0xB58B, 0xC60C, 0xD68D, 0xE70E, 0xF78F};
+  unsigned int c = (unsigned int) ~crc & 0xffff;
+  while (len--) {
+    uint8_t b = *(uint8_t *) buf++;
+    c = crclut[(c ^ b) & 0x0F] ^ (c >> 4);
+    c = crclut[(c ^ (b >> 4)) & 0x0F] ^ (c >> 4);
+  }
+  return (uint16_t) ~c;
+}
+
 static int isbyte(int n) {
   return n >= 0 && n <= 255;
 }

src/util.h

@@ -22,6 +22,9 @@ void mg_free(void *ptr);
 // sensitive data (keys, passwords).
 void mg_bzero(volatile unsigned char *buf, size_t len);
 
+// Fixed-length constant-time byte equality. Use for MACs, tags, signatures.
+bool mg_memeq(const void *a, const void *b, size_t n);
+
 // Fills buf with len cryptographically random bytes. Uses the best available
 // hardware or OS source (hardware RNG, /dev/urandom, CryptGenRandom, etc.).
 // Falls back to rand() with an error log if no strong source is available.
@@ -37,6 +40,10 @@ char *mg_random_str(char *buf, size_t len);
 // a new checksum; pass the result of a prior call to extend over more data.
 uint32_t mg_crc32(uint32_t crc, const char *buf, size_t len);
 
+// Computes CRC16 (HDLC, polynomial 0x8408) over buf/len. Pass crc=0 to start
+// a new checksum; pass the result of a prior call to extend over more data.
+uint16_t mg_crc16(uint16_t crc, const char *buf, size_t len);
+
 // Returns true if path is safe to serve from the filesystem. Rejects paths
 // that start with '~' or '..', or contain a '/../' component, to prevent
 // directory traversal attacks.
@@ -46,6 +53,9 @@ bool mg_path_is_sane(const struct mg_str path);
 // calling context; avoid in event handlers.
 void mg_delayms(unsigned int ms);
 
+uint64_t mg_timegm(unsigned int year, unsigned int month, unsigned int day,
+                   unsigned int hour, unsigned int min, unsigned int sec);
+
 // Packs four byte values into a uint32_t in big-endian order.
 // MG_U32(1, 2, 3, 4) == 0x01020304
 #define MG_U32(a, b, c, d)                                         \

src/version.h

@@ -1 +1 @@
-#define MG_VERSION "7.22"
+#define MG_VERSION "7.23"

test/Makefile

@@ -1,6 +1,6 @@
 SRCS = mongoose.c unit_test.c packed_fs.c
 HDRS = $(wildcard ../src/*.h) $(wildcard ../src/drivers/*.h)
-DEFS ?= -DMG_MAX_HTTP_HEADERS=7 -DMG_ENABLE_LINES -DMG_ENABLE_SSI=1 -DMG_ENABLE_ASSERT=1
+DEFS ?= -DMG_MAX_HTTP_HEADERS=7 -DMG_ENABLE_LINES -DMG_ENABLE_SSI=1 -DMG_ENABLE_ASSERT=1 -DMG_ENABLE_IPV6=$(IPV6)
 WARN ?= -pedantic -W -Wall -Werror -Wshadow -Wdouble-promotion -fno-common -Wconversion -Wundef
 OPTS ?= -O3 -g3
 INCS ?= -Isrc -I.
@@ -25,11 +25,11 @@ PREFIX ?= /usr/local
 LIBDIR ?= $(PREFIX)/lib
 INCLUDEDIR ?= $(PREFIX)/include
 VERSION ?= $(shell cut -d'"' -f2 ../src/version.h)
-COMMON_CFLAGS ?= $(C_WARN) $(WARN) $(INCS) $(DEFS) -DMG_ENABLE_IPV6=$(IPV6) $(TFLAGS) -pthread
+COMMON_CFLAGS ?= $(C_WARN) $(WARN) $(INCS) $(DEFS) $(TFLAGS) -pthread
 CFLAGS ?= $(OPTS) $(ASAN) $(COMMON_CFLAGS)
 VALGRIND_CFLAGS ?= $(OPTS) $(COMMON_CFLAGS)
 VALGRIND_RUN ?= valgrind --tool=memcheck --gen-suppressions=all --leak-check=full --show-leak-kinds=all --leak-resolution=high --track-origins=yes --error-exitcode=1 --exit-on-first-error=yes --fair-sched=yes
-.PHONY: clean_tutorials tutorials mip_test test valgrind
+.PHONY: tutorials mip_test eth_test ppp_test atcmd_test eth_vc98 ppp_vc98 atcmd_vc98 eth_s390 ppp_s390 atcmd_s390 test valgrind
 
 ifeq "$(findstring ++,$(CC))" ""
 # $(CC) does not end with ++, i.e. we're using C. Apply C flags
@@ -78,40 +78,44 @@ ifeq "$(SSL)" "BUILTIN"
 DEFS += -DMG_TLS=MG_TLS_BUILTIN
 endif
 
+tls_multirec/server: FORCE
+ifneq "$(SSL)" ""
+ifeq "$(MULTIREC)" ""
+	$(MAKE) -C tls_multirec CC=gcc
+endif
+endif
+	true
+
+FORCE:
+	true
+
+
 all:
 	$(MAKE) -C ../tutorials/http/http-server
 
-tall: mg_prefix unamalgamated test valgrind fuzz fuzz_tls vc98 vc17 vc22 mingw mingw++ arm armhf riscv s390 tutorials tutorials_win tutorials_embedded mip_test mip_vc98
+tall: mg_prefix unamalgamated test valgrind fuzz fuzz_tls vc98 vc17 vc22 mingw mingw++ arm armhf riscv \
+      diabish ppc_diabish s390 ppc mips tutorials tutorials_win tutorials_embedded
 
-mip_test: mip_test.c mongoose.c mongoose.h packed_fs.c Makefile
-	$(CC) mip_test.c packed_fs.c $(CFLAGS) $(LDFLAGS) -o $@
-	ASAN_OPTIONS=$(ASAN_OPTIONS) $(RUN) ./$@
+tmip: mip_test eth_test ppp_test atcmd_test mip_tap_test pppoe_tap_test mip_port_test mip_diabish \
+      mip_vc98 eth_vc98 ppp_vc98 atcmd_vc98 mip_ppc_diabish mip_s390 eth_s390 ppp_s390 \
+      atcmd_s390 mip_port_s390 mip_ppc eth_ppc ppp_ppc atcmd_ppc mip_port_ppc mip_mips \
+      eth_mips ppp_mips atcmd_mips mip_port_mips
 
-mip_tap_test: mip_x_test.c mip_tap_test.c mongoose.c mongoose.h packed_fs.c Makefile tls_multirec/server
-	$(CC) mip_tap_test.c packed_fs.c $(CFLAGS) $(LDFLAGS) -o $@
-	ASAN_OPTIONS=$(ASAN_OPTIONS) $(RUN) ./$@
+# Amalgamated source files
+mongoose.c: Makefile $(wildcard ../src/*.c) $(wildcard ../src/drivers/*.c)
+	cd .. && (export LC_ALL=C ; cat src/license.h; echo; echo '#include "mongoose.h"' ; (for F in src/*.c src/drivers/*.c ; do echo; echo '#ifdef MG_ENABLE_LINES'; echo "#line 1 \"$$F\""; echo '#endif'; cat $$F | sed -e 's,#include ".*,,'; done))> $@
 
-# bridge UDP port <--> TAP interface
-port_tap_bridge: port_tap_bridge.c
-	cc port_tap_bridge.c -o $@
-
-# requires port_tap_bridge to be running
-mip_port_test: mip_x_test.c mip_port_test.c mongoose.c mongoose.h packed_fs.c Makefile tls_multirec/server
-	$(CC) mip_port_test.c packed_fs.c $(CFLAGS) $(LDFLAGS) -o $@
-	ASAN_OPTIONS=$(ASAN_OPTIONS) $(RUN) ./$@
-
-mip_vc98: mip_test.c mongoose.c mongoose.h packed_fs.c Makefile
-	$(DOCKER) mdashnet/vc98 wine cl mip_test.c packed_fs.c $(VCFLAGS) $(DEFS) $(TFLAGS) /Fe$@.exe
-	$(DOCKER) -e WINEPREFIX=/tmp/wineprefix mdashnet/vc98 wine $@.exe
-
-packed_fs.c: Makefile data/ssi.h fuzz.c data/a.txt data/ca.pem certs/ca.crt certs/server.crt certs/server.key
-	$(CC) $(CFLAGS) pack.c -o pack
-	$(RUN) ./pack Makefile data/ssi.h fuzz.c data/a.txt data/range.txt data/ca.pem certs/ca.crt certs/server.crt certs/server.key certs/client.key certs/client.crt > $@
+mongoose.h: $(HDRS) Makefile
+	cd .. && (export LC_ALL=C ; cat src/license.h; echo; echo '#ifndef MONGOOSE_H'; echo '#define MONGOOSE_H'; echo; cat src/version.h ; echo; echo '#ifdef __cplusplus'; echo 'extern "C" {'; echo '#endif'; cat src/arch.h src/arch_*.h src/os_*.h src/net_ft.h src/net_lwip.h src/net_rl.h src/config.h src/profile.h src/str.h src/queue.h src/fmt.h src/printf.h src/log.h src/timer.h src/fs.h src/util.h src/url.h src/iobuf.h src/base64.h src/md5.h src/sha1.h src/sha256.h src/event.h src/net.h src/http.h src/ssi.h src/tls.h src/tls_x25519.h src/tls_aes128.h src/tls_uecc.h src/tls_chacha20.h src/tls_rsa.h src/tls_mbed.h src/tls_openssl.h src/ws.h src/sntp.h src/mqtt.h src/dns.h src/modbus.h src/json.h src/jwt.h src/rpc.h src/dash.h src/ota.h src/flash.h src/wifi.h src/l2.h src/net_builtin.h src/bsd.h src/drivers/*.h | sed -e '/keep/! s,#include ".*,,' -e 's,^#pragma once,,'; echo; echo '#ifdef __cplusplus'; echo '}'; echo '#endif'; echo '#endif  // MONGOOSE_H')> $@
 
 # Check that all external (exported) symbols have "mg_" prefix
 mg_prefix: mongoose.c mongoose.h
 	$(CC) mongoose.c $(CFLAGS) -c -o /tmp/x.o && nm /tmp/x.o | grep ' T ' | grep -v 'mg_' ; test $$? = 1
 
+test: Makefile mongoose.h $(SRCS) tls_multirec/server
+	$(CC) $(SRCS) $(CFLAGS) $(LDFLAGS) -o unit_test
+	ASAN_OPTIONS=$(ASAN_OPTIONS) $(RUN) ./unit_test
+
 musl: test
 musl: ASAN =
 musl: WARN += -Wno-sign-conversion
@@ -143,22 +147,6 @@ fuzz_tls2: mongoose.c mongoose.h Makefile fuzz_tls.c
 	$(RUN) ./fuzzer_tls $(FUZZDATA)
 
 
-
-test: Makefile mongoose.h $(SRCS) tls_multirec/server
-	$(CC) $(SRCS) $(CFLAGS) $(LDFLAGS) -o unit_test
-	ASAN_OPTIONS=$(ASAN_OPTIONS) $(RUN) ./unit_test
-
-tls_multirec/server: FORCE
-ifneq "$(SSL)" ""
-ifeq "$(MULTIREC)" ""
-	$(MAKE) -C tls_multirec CC=gcc
-endif
-endif
-	true
-
-FORCE:
-	true
-
 coverage: CFLAGS += -coverage
 coverage: test
 	gcov -l -n *.gcno | sed '/^$$/d' | sed 'N;s/\n/ /'
@@ -178,6 +166,16 @@ misra:
 	cppcheck --addon=misra --clang -DMG_ENABLE_LINES=1 -DMG_ENABLE_SSI=1 mongoose.c  >>/tmp/x 2>&1
 	less /tmp/x
 
+arm: DEFS += -DMG_ENABLE_POSIX_FS=0 -DMG_ENABLE_TCPIP=1 -DMG_ENABLE_TCPIP_DRIVER_INIT=0 -DMG_ARCH=MG_ARCH_ARMGCC -DNO_SLEEP_ABORT
+arm: mongoose.h $(SRCS) mip_test.c
+	$(DOCKER) mdashnet/armgcc arm-none-eabi-gcc -mcpu=cortex-m3 -mthumb $(SRCS) $(OPTS) $(WARN) $(INCS) $(DEFS) $(TFLAGS) -o unit_test -nostartfiles --specs nosys.specs -e 0
+	$(DOCKER) mdashnet/armgcc arm-none-eabi-gcc -mcpu=cortex-m3 -mthumb mip_test.c packed_fs.c $(OPTS) $(WARN) $(INCS) $(DEFS) $(TFLAGS) -o mip_test -nostartfiles --specs nosys.specs -e 0
+
+riscv: DEFS += -DMG_ENABLE_POSIX_FS=0 -DMG_ENABLE_TCPIP=1 -DMG_ENABLE_TCPIP_DRIVER_INIT=0 -DMG_ARCH=MG_ARCH_ARMGCC -DNO_SLEEP_ABORT
+riscv: mongoose.h $(SRCS) mip_test.c
+	$(DOCKER) mdashnet/riscv riscv-none-elf-gcc -march=rv32imc -mabi=ilp32 $(SRCS) $(OPTS) $(WARN) $(INCS) $(DEFS) $(TFLAGS) -o unit_test
+	$(DOCKER) mdashnet/riscv riscv-none-elf-gcc -march=rv32imc -mabi=ilp32 mip_test.c packed_fs.c $(OPTS) $(WARN) $(INCS) $(DEFS) $(TFLAGS) -o mip_test
+
 # https://ddanilov.me/how-signals-are-handled-in-a-docker-container
 armhf: ASAN=
 armhf: IPV6=0
@@ -185,6 +183,21 @@ armhf: CC = $(DOCKER) mdashnet/armhf cc
 armhf: RUN = $(DOCKER) --init mdashnet/armhf
 armhf: test
 
+# C89 FOLKS
+diabish: CC = gcc
+diabish: CFLAGS += -std=gnu89 -Werror=declaration-after-statement -Werror=vla -Wno-pedantic
+diabish: test
+# end-of
+
+# C89 + BIG-ENDIAN FOLKS
+ppc_diabish: ASAN=
+ppc_diabish: CFLAGS += -std=gnu89 -Werror=declaration-after-statement -Werror=vla -Wno-pedantic
+ppc_diabish: CC = $(DOCKER) dockcross/linux-ppc powerpc-unknown-linux-gnu-gcc -static
+ppc_diabish: RUN = qemu-ppc-static
+ppc_diabish: test
+# end-of
+
+# BIG-ENDIAN FOLKS
 s390: ASAN=
 s390: IPV6=0
 s390: CFLAGS += -Wno-stringop-overflow
@@ -192,27 +205,19 @@ s390: CC = $(DOCKER) mdashnet/s390 cc
 s390: RUN = $(DOCKER) --init mdashnet/s390
 s390: test
 
-mip_s390: ASAN=
-mip_s390: CC = $(DOCKER) mdashnet/s390 cc
-mip_s390: RUN = $(DOCKER) --init mdashnet/s390
-mip_s390: mip_test
+ppc: ASAN=
+ppc: CC = $(DOCKER) dockcross/linux-ppc powerpc-unknown-linux-gnu-gcc -static
+ppc: RUN = $(DOCKER) --init vicamo/debian:stable-powerpc # doesn't have curl
+ppc: test
 
-mip_port_s390: ASAN=
-mip_port_s390: IPV6=0
-# This test requires curl, not present in this image
-mip_port_s390: CFLAGS += -DNO_HTTPSERVER_TEST
-mip_port_s390: CC = $(DOCKER) mdashnet/s390 cc
-mip_port_s390: RUN = $(DOCKER) --init mdashnet/s390
-mip_port_s390: mip_port_test
-
-arm: DEFS += -DMG_ENABLE_POSIX_FS=0 -DMG_ENABLE_TCPIP=1 -DMG_ENABLE_TCPIP_DRIVER_INIT=0 -DMG_ARCH=MG_ARCH_ARMGCC -DNO_SLEEP_ABORT
-arm: mongoose.h $(SRCS)
-	$(DOCKER) mdashnet/armgcc arm-none-eabi-gcc -mcpu=cortex-m3 -mthumb $(SRCS) $(OPTS) $(WARN) $(INCS) $(DEFS) $(TFLAGS) -o unit_test -nostartfiles --specs nosys.specs -e 0
-
-riscv: DEFS += -DMG_ENABLE_POSIX_FS=0 -DMG_ENABLE_TCPIP=1 -DMG_ENABLE_TCPIP_DRIVER_INIT=0 -DMG_ARCH=MG_ARCH_ARMGCC -DNO_SLEEP_ABORT
-riscv: mongoose.h $(SRCS)
-	$(DOCKER) mdashnet/riscv riscv-none-elf-gcc -march=rv32imc -mabi=ilp32 $(SRCS) $(OPTS) $(WARN) $(INCS) $(DEFS) $(TFLAGS) -o unit_test
+mips: ASAN=
+mips: CC = $(DOCKER) dockcross/linux-mips mips-unknown-linux-gnu-gcc -static
+mips: RUN = $(DOCKER) --init vicamo/debian:stable-mips # not working in GH (?)
+mips: test
+# end-of
 
+# Windows
+vc98: IPV6=0  # VC98 does NOT support IPV6 sockets
 vc98: Makefile mongoose.h $(SRCS)
 	$(DOCKER) mdashnet/vc98 wine cl $(SRCS) $(VCFLAGS) $(DEFS) $(TFLAGS) /Fe$@.exe
 	$(DOCKER) -e WINEPREFIX=/tmp/wineprefix mdashnet/vc98 wine $@.exe
@@ -232,7 +237,9 @@ mingw: Makefile mongoose.h $(SRCS)
 mingw++: Makefile mongoose.h $(SRCS)
 	$(DOCKER) mdashnet/mingw x86_64-w64-mingw32-g++ $(SRCS) -W -Wall -Werror -I. $(DEFS) $(TFLAGS) -lws2_32 -lbcrypt -o $@.exe
 	@echo "NOT RUNNING"
+# end-of
 
+# Linux easter eggs
 linux-libs: CFLAGS += -fPIC
 linux-libs: LDFLAGS += -Wl,-soname,libmongoose.so.$(VERSION)
 linux-libs: mongoose.o
@@ -247,11 +254,10 @@ install: linux-libs
 uninstall:
 	rm -rf $(DESTDIR)$(LIBDIR)/libmongoose.a $(DESTDIR)$(LIBDIR)/libmongoose.so.$(VERSION) $(DESTDIR)$(INCLUDEDIR)/mongoose.h $(DESTDIR)$(LIBDIR)/libmongoose.so
 
-mongoose.c: Makefile $(wildcard ../src/*.c) $(wildcard ../src/drivers/*.c)
-	cd .. && (export LC_ALL=C ; cat src/license.h; echo; echo '#include "mongoose.h"' ; (for F in src/*.c src/drivers/*.c ; do echo; echo '#ifdef MG_ENABLE_LINES'; echo "#line 1 \"$$F\""; echo '#endif'; cat $$F | sed -e 's,#include ".*,,'; done))> $@
 
-mongoose.h: $(HDRS) Makefile
-	cd .. && (cat src/license.h; echo; echo '#ifndef MONGOOSE_H'; echo '#define MONGOOSE_H'; echo; cat src/version.h ; echo; echo '#ifdef __cplusplus'; echo 'extern "C" {'; echo '#endif'; cat src/arch.h src/arch_*.h src/os_*.h src/net_ft.h src/net_lwip.h src/net_rl.h src/config.h src/profile.h src/str.h src/queue.h src/fmt.h src/printf.h src/log.h src/timer.h src/fs.h src/util.h src/url.h src/iobuf.h src/base64.h src/md5.h src/sha1.h src/sha256.h src/event.h src/net.h src/http.h src/ssi.h src/tls.h src/tls_x25519.h src/tls_aes128.h src/tls_uecc.h src/tls_chacha20.h src/tls_rsa.h src/tls_mbed.h src/tls_openssl.h src/ws.h src/sntp.h src/mqtt.h src/dns.h src/modbus.h src/json.h src/rpc.h src/dash.h src/ota.h src/flash.h src/wifi.h src/l2.h src/net_builtin.h src/bsd.h src/drivers/*.h | sed -e '/keep/! s,#include ".*,,' -e 's,^#pragma once,,'; echo; echo '#ifdef __cplusplus'; echo '}'; echo '#endif'; echo '#endif  // MONGOOSE_H')> $@
+packed_fs.c: Makefile data/ssi.h fuzz.c data/a.txt data/range.txt data/ca.pem certs/ca.crt certs/server.crt certs/server.key certs/client.key certs/client.crt
+	$(CC) $(CFLAGS) pack.c -o pack
+	$(RUN) ./pack Makefile data/ssi.h fuzz.c data/a.txt data/range.txt data/ca.pem certs/ca.crt certs/server.crt certs/server.key certs/client.key certs/client.crt > $@
 
 
 clean: clean_tutorials clean_tutorials_embedded
@@ -261,6 +267,154 @@ clean: clean_tutorials clean_tutorials_embedded
 	#find tutorials -maxdepth 3 -name zephyr -prune -o -name Makefile -print | xargs dirname | xargs -n1 make clean -C
 
 
+# MIP (net_builtin + L2 + driver) TESTS
+
+mip_test: mip_test.c mongoose.c mongoose.h packed_fs.c Makefile
+	$(CC) mip_test.c packed_fs.c $(CFLAGS) $(LDFLAGS) -o $@
+	ASAN_OPTIONS=$(ASAN_OPTIONS) $(RUN) ./$@
+
+eth_test: eth_test.c mongoose.c mongoose.h Makefile
+	$(CC) eth_test.c $(CFLAGS) $(LDFLAGS) -o $@
+	ASAN_OPTIONS=$(ASAN_OPTIONS) $(RUN) ./$@
+
+ppp_test: ppp_test.c mongoose.c mongoose.h Makefile
+	$(CC) ppp_test.c $(CFLAGS) $(LDFLAGS) -o $@
+	ASAN_OPTIONS=$(ASAN_OPTIONS) $(RUN) ./$@
+
+atcmd_test: atcmd_test.c mongoose.c mongoose.h Makefile
+	$(CC) atcmd_test.c $(CFLAGS) $(LDFLAGS) -o $@
+	ASAN_OPTIONS=$(ASAN_OPTIONS) $(RUN) ./$@
+
+mip_tap_test: mip_x_test.c mip_tap_test.c mongoose.c mongoose.h packed_fs.c Makefile tls_multirec/server
+	$(CC) mip_tap_test.c packed_fs.c $(CFLAGS) $(LDFLAGS) -o $@
+	ASAN_OPTIONS=$(ASAN_OPTIONS) $(RUN) ./$@
+
+pppoe_tap_test: pppoe_tap_test.c mongoose.c mongoose.h Makefile
+	$(CC) pppoe_tap_test.c $(CFLAGS) $(LDFLAGS) -o $@
+	ASAN_OPTIONS=$(ASAN_OPTIONS) $(RUN) ./$@
+
+# bridge UDP port <--> TAP interface
+port_tap_bridge: port_tap_bridge.c
+	cc port_tap_bridge.c -o $@
+
+# requires port_tap_bridge to be running
+mip_port_test: mip_x_test.c mip_port_test.c mongoose.c mongoose.h packed_fs.c Makefile tls_multirec/server
+	$(CC) mip_port_test.c packed_fs.c $(CFLAGS) $(LDFLAGS) -o $@
+	ASAN_OPTIONS=$(ASAN_OPTIONS) $(RUN) ./$@
+
+# C89 FOLKS
+mip_diabish: CC = gcc
+mip_diabish: CFLAGS += -std=gnu89 -Werror=declaration-after-statement -Werror=vla -Wno-pedantic
+mip_diabish: mip_test
+
+mip_vc98: mip_test.c mongoose.c mongoose.h packed_fs.c Makefile
+	$(DOCKER) mdashnet/vc98 wine cl mip_test.c packed_fs.c $(VCFLAGS) $(DEFS) $(TFLAGS) /Fe$@.exe
+	$(DOCKER) -e WINEPREFIX=/tmp/wineprefix mdashnet/vc98 wine $@.exe
+
+eth_vc98: eth_test.c mongoose.c mongoose.h Makefile
+	$(DOCKER) mdashnet/vc98 wine cl eth_test.c $(VCFLAGS) $(DEFS) $(TFLAGS) /Fe$@.exe
+	$(DOCKER) -e WINEPREFIX=/tmp/wineprefix mdashnet/vc98 wine $@.exe
+
+ppp_vc98: ppp_test.c driver_mock.c mongoose.c mongoose.h Makefile
+	$(DOCKER) mdashnet/vc98 wine cl ppp_test.c $(VCFLAGS) $(DEFS) $(TFLAGS) /Fe$@.exe
+	$(DOCKER) -e WINEPREFIX=/tmp/wineprefix mdashnet/vc98 wine $@.exe
+
+atcmd_vc98: atcmd_test.c mongoose.c mongoose.h Makefile
+	$(DOCKER) mdashnet/vc98 wine cl atcmd_test.c $(VCFLAGS) $(DEFS) $(TFLAGS) /Fe$@.exe
+	$(DOCKER) -e WINEPREFIX=/tmp/wineprefix mdashnet/vc98 wine $@.exe
+# end-of
+
+# C89 + BIG-ENDIAN FOLKS
+mip_ppc_diabish: ASAN=
+mip_ppc_diabish: CFLAGS += -std=gnu89 -Werror=declaration-after-statement -Werror=vla -Wno-pedantic
+mip_ppc_diabish: CC = $(DOCKER) dockcross/linux-ppc powerpc-unknown-linux-gnu-gcc -static
+mip_ppc_diabish: RUN = qemu-ppc-static
+mip_ppc_diabish: mip_test
+# end-of
+
+# BIG-ENDIAN FOLKS
+mip_s390: ASAN=
+mip_s390: CFLAGS += -Wno-stringop-overflow
+mip_s390: CC = $(DOCKER) mdashnet/s390 cc
+mip_s390: RUN = $(DOCKER) --init mdashnet/s390
+mip_s390: mip_test
+
+eth_s390: ASAN=
+eth_s390: CC = $(DOCKER) mdashnet/s390 cc
+eth_s390: RUN = $(DOCKER) --init mdashnet/s390
+eth_s390: eth_test
+
+ppp_s390: ASAN=
+ppp_s390: CC = $(DOCKER) mdashnet/s390 cc
+ppp_s390: RUN = $(DOCKER) --init mdashnet/s390
+ppp_s390: ppp_test
+
+atcmd_s390: ASAN=
+atcmd_s390: CC = $(DOCKER) mdashnet/s390 cc
+atcmd_s390: RUN = $(DOCKER) --init mdashnet/s390
+atcmd_s390: atcmd_test
+
+mip_port_s390: ASAN=
+mip_port_s390: CFLAGS += -Wno-stringop-overflow -DNO_HTTPSERVER_TEST # This test requires curl, not present in this image
+mip_port_s390: CC = $(DOCKER) mdashnet/s390 cc
+mip_port_s390: RUN = $(DOCKER) --init mdashnet/s390
+mip_port_s390: mip_port_test
+
+mip_ppc: ASAN=
+mip_ppc: CC = $(DOCKER) dockcross/linux-ppc powerpc-unknown-linux-gnu-gcc -static -Wno-maybe-uninitialized
+mip_ppc: RUN = qemu-ppc-static
+mip_ppc: mip_test
+
+eth_ppc: ASAN=
+eth_ppc: CC = $(DOCKER) dockcross/linux-ppc powerpc-unknown-linux-gnu-gcc -static -Wno-maybe-uninitialized
+eth_ppc: RUN = qemu-ppc-static
+eth_ppc: eth_test
+
+ppp_ppc: ASAN=
+ppp_ppc: CC = $(DOCKER) dockcross/linux-ppc powerpc-unknown-linux-gnu-gcc -static -Wno-maybe-uninitialized
+ppp_ppc: RUN = qemu-ppc-static
+ppp_ppc: ppp_test
+
+atcmd_ppc: ASAN=
+atcmd_ppc: CC = $(DOCKER) dockcross/linux-ppc powerpc-unknown-linux-gnu-gcc -static -Wno-maybe-uninitialized
+atcmd_ppc: RUN = qemu-ppc-static
+atcmd_ppc: atcmd_test
+
+mip_port_ppc: ASAN=
+mip_port_ppc: CFLAGS += -DNO_HTTPSERVER_TEST # *** avoid system() calls, no OS image !
+mip_port_ppc: CC = $(DOCKER) dockcross/linux-ppc powerpc-unknown-linux-gnu-gcc -static -Wno-maybe-uninitialized
+mip_port_ppc: RUN = qemu-ppc-static
+mip_port_ppc: mip_port_test
+
+mip_mips: ASAN=
+mip_mips: CC = $(DOCKER) dockcross/linux-mips mips-unknown-linux-gnu-gcc -static
+mip_mips: RUN = qemu-mips-static
+mip_mips: mip_test
+
+eth_mips: ASAN=
+eth_mips: CC = $(DOCKER) dockcross/linux-mips mips-unknown-linux-gnu-gcc -static
+eth_mips: RUN = qemu-mips-static
+eth_mips: eth_test
+
+ppp_mips: ASAN=
+ppp_mips: CC = $(DOCKER) dockcross/linux-mips mips-unknown-linux-gnu-gcc -static
+ppp_mips: RUN = qemu-mips-static
+ppp_mips: ppp_test
+
+atcmd_mips: ASAN=
+atcmd_mips: CC = $(DOCKER) dockcross/linux-mips mips-unknown-linux-gnu-gcc -static
+atcmd_mips: RUN = qemu-mips-static
+atcmd_mips: atcmd_test
+
+mip_port_mips: ASAN=
+mip_port_mips: CFLAGS += -DNO_HTTPSERVER_TEST # *** avoid system() calls, no OS image !
+mip_port_mips: CC = $(DOCKER) dockcross/linux-mips mips-unknown-linux-gnu-gcc -static
+mip_port_mips: RUN = qemu-mips-static
+mip_port_mips: mip_port_test
+# end-of
+
+# TUTORIALs TESTS
+
 tutorials:
 	@for X in $(TUTORIALS); do test -f $$X/Makefile || continue; $(MAKE) -C $$X example || exit 1; done
 clean_tutorials:

test/atcmd_test.c

@@ -0,0 +1,173 @@
+#define MG_ENABLE_TCPIP 1
+#define MG_ENABLE_TCPIP_DRIVER_INIT 0
+#define MG_ENABLE_DRIVER_ATCMD 1
+
+#include "mongoose.c"
+
+static int s_num_tests = 0;
+static bool s_error = false;
+
+#ifdef NO_ABORT
+static int s_abort = 0;
+#define ABORT() ++s_abort, s_error = true
+#else
+#ifdef NO_SLEEP_ABORT
+#define ABORT() abort()
+#else
+#define ABORT()                       \
+  sleep(2); /* 2s, GH print reason */ \
+  abort();
+#endif
+#endif
+
+#define ASSERT(expr)                                            \
+  do {                                                          \
+    s_num_tests++;                                              \
+    if (!(expr)) {                                              \
+      printf("FAILURE %s:%d: %s\n", __FILE__, __LINE__, #expr); \
+      fflush(stdout);                                           \
+      ABORT();                                                  \
+    }                                                           \
+  } while (0)
+
+struct uart_mock {
+  uint8_t rx[2048];
+  uint8_t tx[256];
+  size_t rx_len;
+  size_t rx_pos;
+  size_t tx_len;
+  int reset_count;
+};
+
+struct test_ctx {
+  struct mg_tcpip_if ifp;
+  struct mg_tcpip_driver_atcmd_data dd;
+  struct uart_mock mock;
+  char qbuf[1506];
+};
+
+static void mock_reset(void *arg) {
+  struct uart_mock *mock = (struct uart_mock *) arg;
+  mock->reset_count++;
+}
+
+static void mock_tx(void *arg, uint8_t b) {
+  struct uart_mock *mock = (struct uart_mock *) arg;
+  ASSERT(mock->tx_len < sizeof(mock->tx));
+  mock->tx[mock->tx_len++] = b;
+}
+
+static int mock_rx(void *arg) {
+  struct uart_mock *mock = (struct uart_mock *) arg;
+  return mock->rx_pos < mock->rx_len ? mock->rx[mock->rx_pos++] : -1;
+}
+
+static void mock_rx_add(struct uart_mock *mock, const void *buf, size_t len) {
+  ASSERT(mock->rx_len + len <= sizeof(mock->rx));
+  memcpy(mock->rx + mock->rx_len, buf, len);
+  mock->rx_len += len;
+}
+
+static void init_if(struct test_ctx *ctx) {
+  memset(ctx, 0, sizeof(*ctx));
+  ctx->ifp.driver_data = &ctx->dd;
+  ASSERT(mg_atcmd_init(&ctx->ifp) == true);
+  ASSERT(ctx->ifp.recv_queue.size <= sizeof(ctx->qbuf));
+  ctx->ifp.recv_queue.buf = ctx->qbuf;
+}
+
+static void reset_if(struct test_ctx *ctx, const char **script,
+                     bool no_byte_stuff) {
+  memset(&ctx->dd, 0, sizeof(ctx->dd));
+  memset(&ctx->mock, 0, sizeof(ctx->mock));
+  ctx->ifp.driver_data = &ctx->dd;
+  ctx->ifp.recv_queue.head = 0;
+  ctx->ifp.recv_queue.tail = 0;
+  ctx->dd.usart = &ctx->mock;
+  ctx->dd.reset = mock_reset;
+  ctx->dd.tx = mock_tx;
+  ctx->dd.rx = mock_rx;
+  ctx->dd.script = script;
+  ctx->dd.no_byte_stuff = no_byte_stuff;
+}
+
+#define DASHBOARD(x) \
+  printf("HEALTH_DASHBOARD\t\"%s\": %s,\n", x, s_error ? "false" : "true")
+
+int main(void) {
+  struct test_ctx ctx;
+  init_if(&ctx);
+
+  s_error = false;
+  {  // Send AT command, receive OK
+    static const char *script[] = {"AT\r\n", "\r\nOK\r\n", NULL};
+    static const uint8_t at[] = {'A', 'T', '\r', '\n'};
+    static const uint8_t ok[] = {'\r', '\n', 'O', 'K', '\r', '\n'};
+    reset_if(&ctx, script, false);
+
+    ASSERT(mg_atcmd_poll(&ctx.ifp, true) == false);
+    ASSERT(ctx.mock.tx_len == sizeof(at));
+    ASSERT(memcmp(ctx.mock.tx, at, sizeof(at)) == 0);
+    ASSERT(ctx.dd.link == false);
+    mock_rx_add(&ctx.mock, ok, sizeof(ok));
+    ASSERT(mg_atcmd_poll(&ctx.ifp, true) == true);
+    ASSERT(ctx.dd.link == true);
+    ASSERT(ctx.dd.script_index == -1);
+    ASSERT(ctx.mock.reset_count == 0);
+  }
+  DASHBOARD("atcmd");
+
+  s_error = false;
+  {  // HDLC byte stuffing and unstuffing
+    static const uint8_t payload[] = {0x00, 0x01, 'A', 0x7d, 0x7e, 0x20};
+    static const uint8_t frame[] = {0x7e, 0x7d, 0x20, 0x7d, 0x21, 'A',
+                                    0x7d, 0x5d, 0x7d, 0x5e, 0x20, 0x7e};
+    uint8_t buf[sizeof(payload)];
+    reset_if(&ctx, NULL, false);
+    ASSERT(mg_atcmd_poll(&ctx.ifp, true) == true);
+
+    ASSERT(mg_atcmd_tx(payload, sizeof(payload), &ctx.ifp) == sizeof(payload));
+    ASSERT(ctx.mock.tx_len == sizeof(frame));
+    ASSERT(memcmp(ctx.mock.tx, frame, sizeof(frame)) == 0);
+
+    mock_rx_add(&ctx.mock, frame, sizeof(frame));
+    ASSERT(mg_atcmd_rx(buf, sizeof(buf), &ctx.ifp) == sizeof(payload));
+    ASSERT(memcmp(buf, payload, sizeof(payload)) == 0);
+  }
+  {  // HDLC framing with byte stuffing disabled
+    static const uint8_t payload[] = {0x00, 0x01, 'A', 0x7d, 0x20};
+    static const uint8_t frame[] = {0x7e, 0x00, 0x01, 'A', 0x7d, 0x20, 0x7e};
+    uint8_t buf[sizeof(payload)];
+    reset_if(&ctx, NULL, true);
+    ASSERT(mg_atcmd_poll(&ctx.ifp, true) == true);
+
+    ASSERT(mg_atcmd_tx(payload, sizeof(payload), &ctx.ifp) == sizeof(payload));
+    ASSERT(ctx.mock.tx_len == sizeof(frame));
+    ASSERT(memcmp(ctx.mock.tx, frame, sizeof(frame)) == 0);
+
+    mock_rx_add(&ctx.mock, frame, sizeof(frame));
+    ASSERT(mg_atcmd_rx(buf, sizeof(buf), &ctx.ifp) == sizeof(payload));
+    ASSERT(memcmp(buf, payload, sizeof(payload)) == 0);
+  }
+  {  // Oversized frame is rejected
+    uint8_t buf[8];
+    reset_if(&ctx, NULL, true);
+    ASSERT(mg_atcmd_poll(&ctx.ifp, true) == true);
+
+    mock_rx_add(&ctx.mock, "\x7e", 1);
+    memset(ctx.mock.rx + ctx.mock.rx_len, 'A', sizeof(buf) + 1);
+    ctx.mock.rx_len += sizeof(buf) + 1;
+    mock_rx_add(&ctx.mock, "\x7e", 1);
+
+    ASSERT(mg_atcmd_rx(buf, sizeof(buf), &ctx.ifp) == 0);
+  }
+  printf("HEALTH_DASHBOARD\t\"hdlc\": %s\n",
+         s_error ? "false" : "true");
+
+#ifdef NO_ABORT
+  if (s_abort != 0) return EXIT_FAILURE;
+#endif
+
+  printf("SUCCESS. Total tests: %d\n", s_num_tests);
+  return EXIT_SUCCESS;
+}

test/bsd/FreeRTOSConfig.h

@@ -0,0 +1,38 @@
+#pragma once
+#define FREERTOS_CONFIG_H
+
+#include <stdio.h>
+
+#define configUSE_PREEMPTION 1
+#define configCPU_CLOCK_HZ SYS_FREQUENCY
+#define configTICK_RATE_HZ 1000
+#define configMAX_PRIORITIES 5
+#define configUSE_16_BIT_TICKS 0
+#define configUSE_TICK_HOOK 0
+#define configUSE_IDLE_HOOK 0
+#define configUSE_TIMERS 0
+#define configUSE_CO_ROUTINES 0
+#define configUSE_MALLOC_FAILED_HOOK 0
+#define configUSE_COUNTING_SEMAPHORES 1
+#define configMINIMAL_STACK_SIZE 128
+#define configTOTAL_HEAP_SIZE (1024 * 128)
+#define INCLUDE_vTaskDelay 1
+#define INCLUDE_vTaskDelete 1
+#define INCLUDE_xTaskGetSchedulerState 1
+
+#define configPRIO_BITS 4
+
+#define configLIBRARY_LOWEST_INTERRUPT_PRIORITY 15
+#define configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY 5
+#define configKERNEL_INTERRUPT_PRIORITY \
+  (configLIBRARY_LOWEST_INTERRUPT_PRIORITY << (8 - configPRIO_BITS))
+
+#define configMAX_SYSCALL_INTERRUPT_PRIORITY \
+  (configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY << (8 - configPRIO_BITS))
+
+#define configASSERT(expr) \
+  if (!(expr)) printf("FAILURE %s:%d: %s\n", __FILE__, __LINE__, #expr)
+
+//#define vPortSVCHandler SVC_Handler
+//#define xPortPendSVHandler PendSV_Handler
+//xPortSysTickHandler

test/bsd/Makefile

@@ -0,0 +1,77 @@
+WARN ?= -pedantic -W -Wall -Werror -Wshadow -Wdouble-promotion -fno-common -Wconversion -Wundef
+OPTS ?= -O3 -g3
+ASAN ?= -fsanitize=address,undefined,alignment -fno-sanitize-recover=all -fno-omit-frame-pointer -fno-common
+ASAN_OPTIONS ?= detect_leaks=1
+COMMON_CFLAGS ?= $(C_WARN) $(WARN) -I. -I../.. $(TFLAGS)
+CFLAGS ?= $(OPTS) $(ASAN) $(COMMON_CFLAGS)
+
+ifeq "$(findstring ++,$(CC))" ""
+# $(CC) does not end with ++, i.e. we're using C. Apply C flags
+C_WARN ?= -Wmissing-prototypes -Wstrict-prototypes
+else
+# $(CC) ends with ++, i.e. we're using C++. Apply C++ flags
+C_WARN ?= -Wno-deprecated
+endif
+
+.PHONY: all bsd_test bsd_client shm_tap_bridge shm_port_bridge bsd_s390 clean
+
+TEST_SOURCES = bsd_shm_test.c
+# A C++ application compiles its sources as C++, linking Mongoose and FreeRTOS as C.
+# FreeRTOS does not build as C++, so C sources are compiled separately.
+C_SOURCES = ../../mongoose.c
+C_SOURCES += FreeRTOS-Kernel/portable/MemMang/heap_4.c
+C_SOURCES += FreeRTOS-Kernel/portable/ThirdParty/GCC/Posix/port.c
+C_SOURCES += FreeRTOS-Kernel/portable/ThirdParty/GCC/Posix/utils/wait_for_event.c
+C_SOURCES += $(wildcard FreeRTOS-Kernel/*.c)
+C_OBJECTS = $(notdir $(C_SOURCES:.c=.o))
+C_INPUTS = $(foreach S,$(C_SOURCES),-x c $(S))
+CFLAGS += -IFreeRTOS-Kernel/include 
+CFLAGS += -IFreeRTOS-Kernel/portable/ThirdParty/GCC/Posix -Wno-conversion -Wno-undef
+
+ifeq "$(findstring ++,$(CC))" ""
+TEST_LANGUAGE = c
+else
+TEST_LANGUAGE = c++
+endif
+
+DOCKER_BIN ?= docker
+CWD ?= $(realpath $(CURDIR))
+ROOT_DIR = $(realpath $(CWD)/../..)
+ENV ?= -e Tmp=. -e WINEDEBUG=-all
+DOCKER ?= $(DOCKER_BIN) run --platform linux/amd64 --net=host --rm $(ENV) -v $(ROOT_DIR):$(ROOT_DIR) -w $(CWD)
+
+# Mongoose options are defined in mongoose_config.h, this forces loading and skips OS detection
+CFLAGS_MONGOOSE += -DMG_ARCH=MG_ARCH_CUSTOM
+
+
+all bsd: shm_tap_bridge bsd_client FreeRTOS-Kernel bsd_test
+	ASAN_OPTIONS=$(ASAN_OPTIONS) $(RUN) ./bsd_test $(ARGS)
+
+# requires shm_tap_bridge to be running
+bsd_test: FreeRTOS-Kernel
+	$(CC) $(C_INPUTS) -c $(CFLAGS) $(CFLAGS_MONGOOSE) $(CFLAGS_EXTRA)
+	$(CC) -x $(TEST_LANGUAGE) -c $(TEST_SOURCES) $(CFLAGS) $(CFLAGS_MONGOOSE) $(CFLAGS_EXTRA)
+	$(CC) $(C_OBJECTS) $(TEST_SOURCES:.c=.o) $(CFLAGS) $(CFLAGS_MONGOOSE) $(CFLAGS_EXTRA) -o $@
+
+bsd_client: bsd_client.c
+	$(CC) bsd_client.c -pthread -o $@
+
+# bridge shm queue <--> TAP interface
+shm_tap_bridge: shm_tap_bridge.c shm_queue.h
+	$(CC) shm_tap_bridge.c -pthread -o $@
+
+# requires test/port_tap_bridge to be running
+bsd_s390: ASAN=
+bsd_s390: CC = $(DOCKER) mdashnet/s390 cc
+bsd_s390: RUN = $(DOCKER) --init mdashnet/s390
+bsd_s390: shm_port_bridge bsd_client FreeRTOS-Kernel bsd_test
+	$(RUN) sh -c './shm_port_bridge & pid=$$!; sleep 1; ./bsd_test; rc=$$?; kill $$pid >/dev/null 2>&1; wait $$pid >/dev/null 2>&1; exit $$rc'
+
+shm_port_bridge: shm_port_bridge.c shm_queue.h
+	$(CC) shm_port_bridge.c $(CFLAGS) -pthread -o $@
+
+clean:                    # Cleanup. Delete built program and all build artifacts
+	rm -rf bsd_test bsd_client shm_port_bridge *.o *.obj FreeRTOS-Kernel
+
+FreeRTOS-Kernel:  # FreeRTOS sources
+	git clone -q -c advice.detachedHead=false --depth 1 -b V11.2.0 https://github.com/FreeRTOS/FreeRTOS-Kernel $@

test/bsd/bsd_client.c

@@ -0,0 +1,114 @@
+#include <arpa/inet.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <unistd.h>
+
+#define PORT 1234
+#define NUM_CONNECTIONS 12
+#define DATA_SIZE (4 * 1024)
+
+static int read_full(int fd, void *buf, size_t len) {
+  static const size_t sizes[] = {1, 7, 17, 255, 256, 257, 511, 512, 4096};
+  char *p = (char *) buf;
+  size_t i = 0;
+  while (len > 0) {
+    size_t nreq = sizes[i++ % (sizeof(sizes) / sizeof(sizes[0]))];
+    ssize_t n;
+    if (nreq > len) nreq = len;
+    n = recv(fd, p, nreq, 0);
+    if (n <= 0) return -1;
+    p += n;
+    len -= (size_t) n;
+  }
+  return 0;
+}
+
+static int write_full(int fd, const void *buf, size_t len) {
+  const char *p = (const char *) buf;
+  while (len > 0) {
+    ssize_t n = send(fd, p, len, 0);
+    if (n <= 0) return -1;
+    p += n;
+    len -= (size_t) n;
+  }
+  return 0;
+}
+
+static void fill_text(char *buf, size_t len) {
+  size_t i;
+  for (i = 0; i < len; i++) buf[i] = (char) (' ' + random() % 95);
+}
+
+static void *worker(void *arg) {
+  const char *host = (const char *) arg;
+  char tx[DATA_SIZE], rx[DATA_SIZE];
+  struct sockaddr_in sa;
+  struct timeval timeout;
+  unsigned port = 0;
+  int fd;
+
+  fill_text(tx, sizeof(tx));
+  memset(rx, 0, sizeof(rx));
+
+  fd = socket(AF_INET, SOCK_STREAM, 0);
+  if (fd < 0) goto fail;
+  timeout.tv_sec = 5;
+  timeout.tv_usec = 0;
+  if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &timeout, sizeof(timeout)) != 0 ||
+      setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &timeout, sizeof(timeout)) != 0)
+    goto fail_close;
+
+  memset(&sa, 0, sizeof(sa));
+  sa.sin_family = AF_INET;
+  sa.sin_port = htons(PORT);
+  if (inet_pton(AF_INET, host, &sa.sin_addr) != 1) goto fail_close;
+  printf("%d CONNECTING\n", fd);
+  if (connect(fd, (struct sockaddr *) &sa, sizeof(sa)) != 0) goto fail_close;
+  {
+    socklen_t len = sizeof(sa);
+    if (getsockname(fd, (struct sockaddr *) &sa, &len) != 0) goto fail_close;
+    port = (unsigned) ntohs(sa.sin_port);
+  }
+  printf("%d CONNECTED port: %u\n", fd, port);
+  printf("%d WRITING\n", fd);
+  if (write_full(fd, tx, sizeof(tx)) != 0) goto fail_close;
+  printf("%d READING\n", fd);
+  if (read_full(fd, rx, sizeof(rx)) != 0) goto fail_close;
+  if (memcmp(tx, rx, sizeof(tx)) != 0) goto fail_close;
+
+  printf("%d OK-CLOSING\n", fd);
+  close(fd);
+  return NULL;
+
+fail_close:
+  printf("%d ERROR-CLOSING\n", fd);
+  close(fd);
+fail:
+  exit(1);
+}
+
+int main(int argc, char *argv[]) {
+  pthread_t threads[NUM_CONNECTIONS];
+  int i;
+
+  if (argc != 2) {
+    fprintf(stderr, "usage: %s IP\n", argv[0]);
+    return 1;
+  }
+
+  srandom(1);
+
+  for (i = 0; i < NUM_CONNECTIONS; i++) {
+    if (pthread_create(&threads[i], NULL, worker, argv[1]) != 0) return 1;
+  }
+
+  for (i = 0; i < NUM_CONNECTIONS; i++) {
+    if (pthread_join(threads[i], NULL) != 0) return 1;
+  }
+
+  return 0;
+}

test/bsd/bsd_shm_test.c

@@ -0,0 +1,115 @@
+#include <errno.h>
+#include <stdio.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+
+#include "mongoose.h"
+#include "shm_queue.h"
+
+#ifndef O_RDWR
+#define O_RDWR 02
+#endif
+
+struct shm_driver_data {
+  const char *name;
+  FILE *fp;
+  struct shm_link *shm;
+};
+
+static struct shm_driver_data shm_data = {
+    SHM_NAME,
+    NULL,
+    NULL,
+};
+
+static bool shm_init(struct mg_tcpip_if *ifp) {
+  struct shm_driver_data *d = (struct shm_driver_data *) ifp->driver_data;
+  int fd;
+
+  fd = shm_open(d->name, O_RDWR, 0600);
+  if (fd < 0) {
+    printf("shm_open failed: %d\n", errno);
+    return false;
+  }
+  d->fp = fdopen(fd, "r+");
+  if (d->fp == NULL) {
+    printf("fdopen failed: %d\n", errno);
+    return false;
+  }
+
+  d->shm = (struct shm_link *) mmap(NULL, sizeof(*d->shm),
+                                    PROT_READ | PROT_WRITE, MAP_SHARED,
+                                    fileno(d->fp), 0);
+  if (d->shm == MAP_FAILED) {
+    printf("mmap failed: %d\n", errno);
+    fclose(d->fp);
+    d->fp = NULL;
+    d->shm = NULL;
+    return false;
+  }
+
+  return true;
+}
+
+static size_t shm_tx(const void *buf, size_t len, struct mg_tcpip_if *ifp) {
+  struct shm_driver_data *d = (struct shm_driver_data *) ifp->driver_data;
+
+  if (!shm_queue_push(&d->shm->to_tap, buf, len)) {
+    printf("\nFRAME LOST\n");
+    return 0;
+  }
+  return len;
+}
+
+static size_t shm_rx(void *buf, size_t len, struct mg_tcpip_if *ifp) {
+  struct shm_driver_data *d = (struct shm_driver_data *) ifp->driver_data;
+  return shm_queue_pop(&d->shm->from_tap, buf, len);
+}
+
+static bool shm_poll(struct mg_tcpip_if *ifp, bool s1) {
+  return s1 && ifp->driver_data ? true : false;
+}
+
+static struct mg_tcpip_driver shm_driver = {
+    shm_init,
+    shm_tx,
+    shm_rx,
+    shm_poll,
+};
+
+
+bool mg_random(void *buf, size_t len) {
+  bool success = false;
+  unsigned char *p = (unsigned char *) buf;
+  FILE *fp = fopen("/dev/urandom", "rb");
+  if (fp != NULL) {
+    if (fread(buf, 1, len, fp) == len) success = true;
+    fclose(fp);
+  }
+  // If everything above did not work, fallback to a pseudo random generator
+  if (success == false) {
+    printf("\nWeak RNG: using rand()\n");
+    while (len--) *p++ = (unsigned char) (rand() & 255);
+  }
+  return success;
+}
+
+
+#include "bsd_x_test.c"
+
+
+int main(void) {
+  bool result;
+  const char *debug_level = getenv("V");
+  // Setup interface
+  const char *mac = "02:00:01:02:03:78";  // MAC address
+
+  printf("Opening SHM interface\n");
+  usleep(200000);  // 200 ms
+
+  result = bsd_x_test(&shm_driver, &shm_data, mac, debug_level);
+  if (shm_data.shm != NULL) munmap(shm_data.shm, sizeof(*shm_data.shm));
+  if (shm_data.fp != NULL) fclose(shm_data.fp);
+  if (!result) return EXIT_FAILURE;
+  return EXIT_SUCCESS;
+}

test/bsd/bsd_x_test.c

@@ -0,0 +1,275 @@
+#define BSDTEST_USING_DHCP 1
+
+#include <spawn.h>
+#include <sys/wait.h>
+
+static int s_num_tests = 0;
+static bool s_error = false;
+static volatile bool s_done = false, s_wait;
+
+#ifdef NO_ABORT
+static int s_abort = 0;
+#define ABORT() ++s_abort, s_error = true
+#else
+#ifdef NO_SLEEP_ABORT
+#define ABORT() abort()
+#else
+#define ABORT()                       \
+  sleep(2); /* 2s, GH print reason */ \
+  abort();
+#endif
+#endif
+
+#define ASSERT(expr)                                            \
+  do {                                                          \
+    s_num_tests++;                                              \
+    if (!(expr)) {                                              \
+      printf("FAILURE %s:%d: %s\n", __FILE__, __LINE__, #expr); \
+      fflush(stdout);                                           \
+      ABORT();                                                  \
+    }                                                           \
+  } while (0)
+
+struct client_data {
+  char hostname[64];
+  uint32_t ip;
+  bool done;
+};
+
+// client_task: connects to hostname:80, fetches "/", logs response length.
+static void client_task(void *args) {
+  int fd, c;
+  struct client_data *d = (struct client_data *) args;
+  char req[256];
+  fd = socket(AF_INET, SOCK_STREAM, 0);
+  struct sockaddr_in sa;
+  memset(&sa, 0, sizeof(sa));
+  sa.sin_family = AF_INET;
+  sa.sin_port = htons(80);
+  memcpy(&sa.sin_addr, &d->ip, 4);
+  c = connect(fd, (struct sockaddr *) &sa, sizeof(sa));
+  ASSERT(c >= 0);
+  if (c < 0) {
+    MG_ERROR(("connect failed"));
+    close(fd);
+    vTaskDelete(NULL);
+    return;
+  }
+  snprintf(req, sizeof(req),"GET / HTTP/1.0\r\nHost: %s\r\n\r\n", d->hostname);
+  send(fd, req, strlen(req), 0);
+  size_t total = 0;
+  char buf[512];
+  ssize_t n;
+  while ((n = recv(fd, buf, sizeof(buf), 0)) > 0) total += (size_t) n;
+  MG_INFO(("%s response: %lu bytes", d->hostname, (unsigned long) total));
+  ASSERT(total > 0);
+  close(fd);
+  d->done = true;
+  vTaskDelete(NULL);
+  (void) args;
+}
+
+// echo_task: one per accepted connection.  Echoes data back.
+static void echo_task(void *args) {
+  int fd = (int) (uintptr_t) args;
+  static const size_t sizes[] = {1, 7, 17, 255, 256, 257, 511, 512};
+  char buf[512];
+  size_t i = 0;
+  ssize_t n;
+  MG_INFO(("Echo task started: %d", fd));
+  while ((n = recv(fd, buf, sizes[i++ % (sizeof(sizes) / sizeof(sizes[0]))], 0)) > 0)
+    send(fd, buf, (size_t) n, 0);
+  close(fd);
+  vTaskDelete(NULL);
+}
+
+// accept loop.  Waits for incoming connections on port 1234 and spawns
+// an echo_task for each one, allowing concurrent clients.
+static void atask(void *args) {
+  BaseType_t result;
+  mg_bsd_init();
+  int lfd = socket(AF_INET, SOCK_STREAM, 0);
+  struct sockaddr_in sa;
+  memset(&sa, 0, sizeof(sa));
+  sa.sin_family = AF_INET;
+  sa.sin_port = htons(1234);
+  sa.sin_addr.s_addr = INADDR_ANY;
+  bind(lfd, (struct sockaddr *) &sa, sizeof(sa));
+  listen(lfd, 5);
+  fcntl(lfd, F_SETFL, O_NONBLOCK);
+  MG_INFO(("BSD echo server on :1234"));
+  while (!s_wait) {
+    int fd = accept(lfd, NULL, NULL);
+    if (fd < 0) { vTaskDelay(pdMS_TO_TICKS(10)); continue; }
+    // echo_task at higher priority than task1
+    result = xTaskCreate(echo_task, "echo", 512, (void *) (uintptr_t) fd,
+                         configMAX_PRIORITIES - 1, NULL);
+    MG_INFO(("Echo task %d: %s", fd, result == pdPASS ? "created" : "FAILED"));
+    ASSERT(result == pdPASS);
+  }
+  close(lfd);
+  s_wait = false;
+  vTaskDelete(NULL);
+  (void) args;
+}
+
+
+// task2: tests owner.
+static void task2(void *args) {
+  struct mg_mgr *mgr = (struct mg_mgr *)args;  // Event manager
+  char *ip, *cmd[3];
+  pid_t pid;
+  int status;
+  extern char **environ;
+
+#define DASHBOARD(x)  printf("HEALTH_DASHBOARD\t\"%s\": %s,\n", x, s_error ? "false":"true");
+
+  vTaskDelay(pdMS_TO_TICKS(500));  // 500 ms
+  s_error = false;
+  s_wait = false;
+  // atask at higher priority than task1
+  xTaskCreate(atask, "atask", 256,  NULL, configMAX_PRIORITIES - 1, NULL);
+  ip = mg_mprintf("%M", mg_print_ip4, &mgr->ifp->ip);
+  cmd[0] = (char *) "./bsd_client";
+  cmd[1] = ip;
+  cmd[2] = NULL;
+  ASSERT(posix_spawn(&pid, cmd[0], NULL, NULL, cmd, environ) == 0);
+  for (;;) {
+    pid_t r = waitpid(pid, &status, WNOHANG);
+    ASSERT(r >= 0);
+    if (r == pid) break;
+    vTaskDelay(pdMS_TO_TICKS(10));
+  }
+  ASSERT(WIFEXITED(status));
+  ASSERT(WEXITSTATUS(status) == 0);
+  mg_free(ip);
+  s_wait = true;
+  while (s_wait) vTaskDelay(pdMS_TO_TICKS(10));
+  DASHBOARD("accept");
+
+  vTaskDelay(pdMS_TO_TICKS(500));  // 500 ms
+  s_error = false;
+  {
+    struct hostent *h = gethostbyname("invalidhostname");
+    ASSERT(h == NULL);
+    h = gethostbyname("mongoose.ws");
+    ASSERT(h != NULL);
+    if (h == NULL) {
+      MG_ERROR(("DNS failed"));
+       vTaskDelete(NULL);
+      return;
+    }
+  }
+  DASHBOARD("gethostbyname");
+
+  vTaskDelay(pdMS_TO_TICKS(500));  // 500 ms
+  s_error = false;
+  s_wait = true;
+  {
+    struct client_data cd[3];
+    struct hostent *h = gethostbyname("mongoose.ws");
+    strcpy(cd[0].hostname, "mongoose.ws");
+    memcpy(&cd[0].ip, h->h_addr, 4);
+    cd[0].done = false;
+    // client_task at higher priority than task1
+    xTaskCreate(client_task, "client1", 1024, &cd[0], configMAX_PRIORITIES - 1, NULL);
+    h = gethostbyname("cesanta.com");
+    strcpy(cd[1].hostname, "cesanta.com");
+    memcpy(&cd[1].ip, h->h_addr, 4);
+    cd[1].done = false;
+    // client_task at higher priority than task1
+    xTaskCreate(client_task, "client2", 1024, &cd[1], configMAX_PRIORITIES - 1, NULL);
+    h = gethostbyname("google.com");
+    strcpy(cd[2].hostname, "google.com");
+    memcpy(&cd[2].ip, h->h_addr, 4);
+    cd[2].done = false;
+    // client_task at higher priority than task1
+    xTaskCreate(client_task, "client3", 1024, &cd[2], configMAX_PRIORITIES - 1, NULL);
+    while (!cd[0].done || !cd[1].done || !cd[2].done) vTaskDelay(pdMS_TO_TICKS(10));
+  }
+  DASHBOARD("connect");
+  // End task 1
+  s_done = true;
+  while (s_done) vTaskDelay(pdMS_TO_TICKS(10));
+
+  // Clear
+  s_error = false;
+  mg_mgr_free(mgr);
+  ASSERT(mgr->conns == NULL);  // Deconstruction OK
+  printf("HEALTH_DASHBOARD\t\"cleanup\": %s\n", s_error ? "false":"true");
+ // last entry with no comma
+  vTaskEndScheduler();
+}
+
+// task1: network owner.  Runs the Mongoose event loop and the BSD command queue.
+// The interface needs to be started here, as FreeRTOS needs to be running (time base)
+static void task1(void *args) {
+  struct mg_mgr *mgr = (struct mg_mgr *)args;  // Event manager
+
+  // Stack initialization, Network configuration (DHCP lease, ...)
+#if BSDTEST_USING_DHCP == 0
+  MG_INFO(("MIF configuration: Static IP"));
+  ASSERT(mif.ip != 0);     // Check we have a satic IP assigned
+  mg_mgr_poll(&mgr, 0);  // For initialisation
+#else
+  MG_INFO(("MIF configuration: DHCP"));
+  ASSERT(mgr->ifp->ip == 0);  // Check we are set for DHCP
+  while (mgr->ifp->ip == 0 && mg_millis() < 5000) {
+    mg_mgr_poll(mgr, 0);
+  }
+  if (mgr->ifp->ip == 0) MG_ERROR(("No ip assigned (DHCP lease may have failed).\n"));
+  ASSERT(mgr->ifp->ip != 0);  // We have an IP (lease or static)
+#endif
+  while (mgr->ifp->state != MG_TCPIP_STATE_READY) {
+    mg_mgr_poll(mgr, 0);
+  }
+  MG_INFO(("Interface started, starting main loop"));
+  xTaskCreate(task2, "task2", 256,  mgr, configMAX_PRIORITIES - 2, NULL);
+
+  while (!s_done) {
+    mg_mgr_poll(mgr, 0);
+    mg_bsd_poll(mgr);
+    vTaskDelay(1);  // Let idle reclaim deleted echo tasks
+  }
+  s_done = false;
+  vTaskDelete(NULL);
+}
+
+static bool bsd_x_test(struct mg_tcpip_driver *driver, void *driver_data, const char *mac, const char *debug_level) {
+  if (debug_level == NULL) debug_level = "3";
+  mg_log_set(atoi(debug_level));
+
+  struct mg_mgr mgr;  // Event manager
+  mg_mgr_init(&mgr);  // Initialise event manager
+
+  struct mg_tcpip_if mif;
+  memset(&mif, 0, sizeof(mif));
+
+  mif.driver = driver;
+  mif.driver_data = driver_data;
+
+#if BSDTEST_USING_DHCP == 1
+#else
+  mif.ip = mg_htonl(MG_U32(192, 168, 32, 2));  // Triggering a network failure
+  mif.mask = mg_htonl(MG_U32(255, 255, 255, 0));
+  mif.gw = mg_htonl(MG_U32(192, 168, 32, 1));
+#endif
+
+  sscanf(mac, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", &mif.mac[0], &mif.mac[1],
+         &mif.mac[2], &mif.mac[3], &mif.mac[4], &mif.mac[5]);
+
+  mg_tcpip_init(&mgr, &mif);
+  ASSERT(mgr.ifp != NULL);  // driver init succeeded
+  MG_INFO(("Init done, starting interface"));
+  usleep(200000);  // 200 ms
+
+  xTaskCreate(task1, "task1", 2048, &mgr, configMAX_PRIORITIES - 2, NULL);
+  vTaskStartScheduler();
+
+#ifdef NO_ABORT
+  if (s_abort != 0) return false;
+#endif
+
+  printf("SUCCESS. Total tests: %d\n", s_num_tests);
+  return true;
+}

test/bsd/mongoose_config.h

@@ -0,0 +1,30 @@
+#pragma once
+
+// See https://mongoose.ws/documentation/#build-options
+//#undef MG_ARCH
+//#define MG_ARCH MG_ARCH_UNIX
+#define MG_ENABLE_FREERTOS 1
+
+#define MG_ENABLE_TCPIP 1
+#define MG_ENABLE_TCPIP_DRIVER_INIT 0
+#define MG_ENABLE_BSD_SOCKETS 1
+#define MG_ENABLE_BSD_LOG 1
+#define MG_ENABLE_LINES 1 
+#define MG_ENABLE_CUSTOM_RANDOM 1
+
+//#include <ctype.h>
+#include <inttypes.h>
+#include <limits.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>

test/bsd/shm_port_bridge.c

@@ -0,0 +1,138 @@
+#define _POSIX_C_SOURCE 200809L
+
+#include <arpa/inet.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <netinet/in.h>
+#include <signal.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <poll.h>
+#include <unistd.h>
+
+#include "shm_queue.h"
+
+static volatile sig_atomic_t s_signo;
+
+static void signal_handler(int signo) {
+  s_signo = signo;
+}
+
+static int open_udp_socket(void) {
+  const uint16_t port = 0xAA55;      // Local UDP port
+  const uint16_t tap_port = 0x55AA;  // Host port_tap_bridge UDP port
+  struct sockaddr_in port_addr, tap_addr;
+  int fd = socket(AF_INET, SOCK_DGRAM, 0);
+  if (fd < 0) {
+    perror("socket");
+    return -1;
+  }
+
+  memset(&port_addr, 0, sizeof(port_addr));
+  port_addr.sin_family = AF_INET;
+  port_addr.sin_addr.s_addr = htonl(INADDR_ANY);
+  port_addr.sin_port = htons(port);
+  if (bind(fd, (struct sockaddr *) &port_addr, sizeof(port_addr)) < 0) {
+    perror("bind");
+    close(fd);
+    return -1;
+  }
+  printf("Opened UDP socket: 127.0.0.1:%u (0x%04x)\n", (unsigned) port,
+         (unsigned) port);
+
+  memset(&tap_addr, 0, sizeof(tap_addr));
+  tap_addr.sin_family = AF_INET;
+  tap_addr.sin_addr.s_addr = htonl(0x7f000001U);  // 127.0.0.1
+  tap_addr.sin_port = htons(tap_port);
+  if (connect(fd, (struct sockaddr *) &tap_addr, sizeof(tap_addr)) < 0) {
+    perror("connect");
+    close(fd);
+    return -1;
+  }
+  printf("Connected to TAP UDP socket: 127.0.0.1:%u (0x%04x)\n",
+         (unsigned) tap_port, (unsigned) tap_port);
+
+  return fd;
+}
+
+static struct shm_link *open_shm(int *shmfd) {
+  struct shm_link *shm;
+
+  shm_unlink(SHM_NAME);
+  *shmfd = shm_open(SHM_NAME, O_CREAT | O_RDWR, 0600);
+  if (*shmfd < 0) {
+    perror("shm_open");
+    return NULL;
+  }
+  if (ftruncate(*shmfd, (off_t) sizeof(*shm)) != 0) {
+    perror("ftruncate");
+    close(*shmfd);
+    shm_unlink(SHM_NAME);
+    return NULL;
+  }
+  shm = (struct shm_link *) mmap(NULL, sizeof(*shm), PROT_READ | PROT_WRITE,
+                                 MAP_SHARED, *shmfd, 0);
+  if (shm == MAP_FAILED) {
+    perror("mmap");
+    close(*shmfd);
+    shm_unlink(SHM_NAME);
+    return NULL;
+  }
+
+  memset(shm, 0, sizeof(*shm));
+  printf("Opened shared memory: %s\n", SHM_NAME);
+
+  return shm;
+}
+
+int main(void) {
+  int sockfd, shmfd = -1;
+  struct shm_link *shm;
+
+  sockfd = open_udp_socket();
+  if (sockfd < 0) return EXIT_FAILURE;
+  shm = open_shm(&shmfd);
+  if (shm == NULL) {
+    close(sockfd);
+    return EXIT_FAILURE;
+  }
+
+  signal(SIGINT, signal_handler);
+  signal(SIGTERM, signal_handler);
+
+  while (s_signo == 0) {
+    struct pollfd pfd = {sockfd, (short) (POLLIN | POLLPRI), 0};
+    int result = poll(&pfd, 1, 1);
+    if (result < 0 && errno != EINTR) {
+      perror("poll");
+      break;
+    }
+    if (result > 0 && (pfd.revents & (POLLIN | POLLPRI))) {
+      uint8_t buf[FRAME_SIZE];
+      ssize_t nread = recv(sockfd, buf, sizeof(buf), 0);
+      if (nread > 0 &&
+          !shm_queue_push(&shm->from_tap, buf, (size_t) nread)) {
+        printf("FRAME LOST: port -> SHM\n");
+      }
+    }
+    {
+      uint8_t buf[FRAME_SIZE];
+      size_t n = shm_queue_pop(&shm->to_tap, buf, sizeof(buf));
+      if (n > 0) {
+        if (send(sockfd, buf, n, 0) < 0) perror("send");
+      }
+    }
+  }
+
+  munmap(shm, sizeof(*shm));
+  close(shmfd);
+  shm_unlink(SHM_NAME);
+  close(sockfd);
+  return EXIT_SUCCESS;
+}

test/bsd/shm_queue.h

@@ -0,0 +1,60 @@
+#pragma once
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
+#define FRAME_SIZE 1540
+#define FRAME_QUEUE_DEPTH 32
+#define SHM_NAME "/mongoose-shm"
+
+// Keep this SHM ABI semaphore-free. Some S390/Linux headers pull fcntl/socket
+// declarations through <semaphore.h>, colliding with Mongoose BSD prototypes.
+// Each direction is single-producer/single-consumer and polled, so a simple
+// ring is enough for this test path.
+struct shm_frame {
+  size_t len;
+  uint8_t buf[FRAME_SIZE];
+};
+
+struct shm_queue {
+  volatile size_t head;
+  volatile size_t tail;
+  struct shm_frame frames[FRAME_QUEUE_DEPTH];
+};
+
+struct shm_link {
+  struct shm_queue to_tap;
+  struct shm_queue from_tap;
+};
+
+static inline bool shm_queue_push(struct shm_queue *q, const void *buf,
+                                  size_t len) {
+  size_t tail = q->tail, next = (tail + 1) % FRAME_QUEUE_DEPTH;
+  struct shm_frame *f;
+  if (len > sizeof(q->frames[0].buf) || next == q->head) return false;
+  f = &q->frames[tail];
+  memcpy(f->buf, buf, len);
+  f->len = len;
+  __sync_synchronize();
+  q->tail = next;
+  return true;
+}
+
+static inline size_t shm_queue_pop(struct shm_queue *q, void *buf, size_t len) {
+  size_t head = q->head, n;
+  struct shm_frame *f;
+  if (head == q->tail) return 0;
+  __sync_synchronize();
+  f = &q->frames[head];
+  n = f->len;
+  if (n > len) {
+    q->head = (head + 1) % FRAME_QUEUE_DEPTH;
+    return 0;
+  }
+  memcpy(buf, f->buf, n);
+  __sync_synchronize();
+  q->head = (head + 1) % FRAME_QUEUE_DEPTH;
+  return n;
+}

test/bsd/shm_tap_bridge.c

@@ -0,0 +1,110 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/poll.h>
+#include <sys/stat.h>
+#include <signal.h>
+
+#include <linux/if.h>
+#include <linux/if_tun.h>
+#include "shm_queue.h"
+
+static volatile sig_atomic_t s_signo;
+void signal_handler(int signo) {
+  s_signo = signo;
+}
+
+int main(void) {
+  // Setup interface
+  const char *iface = "tap0";             // Network iface
+  const char *tuntap_device = "/dev/net/tun";
+  int fd = open(tuntap_device, O_RDWR);
+  struct ifreq ifr;
+  memset(&ifr, 0, sizeof(ifr));
+  strncpy(ifr.ifr_name, iface, IFNAMSIZ);
+  ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
+  if (ioctl(fd, TUNSETIFF, (void *) &ifr) < 0) {
+    printf("Failed to setup TAP interface: %s", ifr.ifr_name);
+    return EXIT_FAILURE;
+  }
+  printf("Opened TAP interface: %s\n", iface);
+
+  int shmfd;
+  struct shm_link *shm;
+
+  shm_unlink(SHM_NAME);
+  shmfd = shm_open(SHM_NAME, O_CREAT | O_RDWR, 0600);
+  if (shmfd < 0) {
+    printf("shm_open failed: %d\n", errno);
+    return EXIT_FAILURE;
+  }
+  if (ftruncate(shmfd, sizeof(*shm)) != 0) {
+    printf("ftruncate failed: %d\n", errno);
+    return EXIT_FAILURE;
+  }
+  shm = (struct shm_link *) mmap(NULL, sizeof(*shm), PROT_READ | PROT_WRITE,
+                                 MAP_SHARED, shmfd, 0);
+  if (shm == MAP_FAILED) {
+    printf("mmap failed: %d\n", errno);
+    return EXIT_FAILURE;
+  }
+
+  memset(shm, 0, sizeof(*shm));
+  printf("Opened shared memory: %s\n", SHM_NAME);
+  signal(SIGINT, signal_handler);
+  signal(SIGTERM, signal_handler);
+
+  while (s_signo == 0) {
+    struct pollfd pfd[1];
+		int result;
+		do {
+			pfd[0].fd = fd;
+			pfd[0].events = POLLIN | POLLPRI;		// will wait for input available (read ready), use POLLOUT for write
+
+			// only read ready shown here, for write ready use the 3rd arg, and the 4th for exceptions
+			result = poll(pfd, 1, 1);		// 1 pfd, TIMEOUT in milliseconds
+			switch(result) {
+			case -1: 	// error
+				break;
+			case 0: 	// timeout (if a timeout struct was passed to select)
+				break;
+			default: 	// the number of fd/sockets with data available (see pfd.revents for each one);
+        if (pfd[0].revents & (POLLIN | POLLPRI)) {
+          uint8_t buf[FRAME_SIZE];
+          ssize_t nread = read(fd, buf, sizeof(buf));
+//          printf("Got at TAP: %d bytes\n", (int) nread);
+          if (nread > 0) {
+            if (!shm_queue_push(&shm->from_tap, buf, (size_t) nread)) {
+              printf("FRAME LOST: TAP -> SHM\n");
+            }
+//            printf("Sent to SHM\n");
+          }
+        }
+				break;
+			}
+      {
+        uint8_t buf[FRAME_SIZE];
+        size_t n = shm_queue_pop(&shm->to_tap, buf, sizeof(buf));
+        if (n > 0) {
+//      printf("Got at SHM: %d bytes\n", (int) f->len);
+          write(fd, buf, n);
+//      printf("Sent to TAP\n");
+        }
+      }
+		} while (result >= 0 && s_signo == 0);
+    if (result < 0)
+      printf("looks like we got an error here... should I quit ? Waiting for CTRL-C\n");
+	}
+  munmap(shm, sizeof(*shm));
+  close(shmfd);
+  shm_unlink(SHM_NAME);
+  close(fd);
+}

test/eth_test.c

@@ -0,0 +1,283 @@
+#define MG_ENABLE_TCPIP 1
+#define MG_ENABLE_TCPIP_DRIVER_INIT 0
+
+#include "mongoose.c"
+
+static int s_num_tests = 0;
+static bool s_error = false;
+
+#ifdef NO_ABORT
+static int s_abort = 0;
+#define ABORT() ++s_abort, s_error = true
+#else
+#ifdef NO_SLEEP_ABORT
+#define ABORT() abort()
+#else
+#define ABORT()                       \
+  sleep(2); /* 2s, GH print reason */ \
+  abort();
+#endif
+#endif
+
+#define ASSERT(expr)                                            \
+  do {                                                          \
+    s_num_tests++;                                              \
+    if (!(expr)) {                                              \
+      printf("FAILURE %s:%d: %s\n", __FILE__, __LINE__, #expr); \
+      fflush(stdout);                                           \
+      ABORT();                                                  \
+    }                                                           \
+  } while (0)
+
+static const uint8_t s_mac[6] = {2, 3, 4, 5, 6, 7};
+static const uint8_t s_src[6] = {8, 9, 10, 11, 12, 13};
+
+static void reset_if(struct mg_tcpip_if *ifp) {
+  memset(ifp, 0, sizeof(*ifp));
+  memcpy(ifp->mac, s_mac, sizeof(s_mac));
+  ifp->l2type = MG_TCPIP_L2_ETH;
+}
+
+static size_t mk_eth(uint8_t *buf, const uint8_t *dst, uint16_t type,
+                     const uint8_t *payload, size_t len) {
+  struct eth *eth = (struct eth *) buf;
+  memcpy(eth->dst, dst, sizeof(eth->dst));
+  memcpy(eth->src, s_src, sizeof(eth->src));
+  eth->type = mg_htons(type);
+  memcpy(eth + 1, payload, len);
+  return sizeof(*eth) + len;
+}
+
+static size_t mk_vlan(uint8_t *buf, const uint8_t *dst, uint16_t vlan,
+                      uint16_t type, const uint8_t *payload, size_t len) {
+  struct eth *eth = (struct eth *) buf;
+  struct qtag *qtag = (struct qtag *) &eth->type;
+  memcpy(eth->dst, dst, sizeof(eth->dst));
+  memcpy(eth->src, s_src, sizeof(eth->src));
+  qtag->tpid = mg_htons(0x8100);
+  qtag->tci = mg_htons(vlan);
+  MG_STORE_BE16(qtag + 1, type);
+  memcpy((uint8_t *) (qtag + 1) + sizeof(uint16_t), payload, len);
+  return sizeof(*eth) + sizeof(*qtag) + len;
+}
+
+static size_t add_fcs(uint8_t *buf, size_t len) {
+  uint32_t crc = mg_crc32(0, (const char *) buf, len);
+  buf[len++] = (uint8_t) crc;       // store as LE32
+  buf[len++] = (uint8_t) (crc >> 8);
+  buf[len++] = (uint8_t) (crc >> 16);
+  buf[len++] = (uint8_t) (crc >> 24);
+  return len;
+}
+
+#define DASHBOARD(x) \
+  printf("HEALTH_DASHBOARD\t\"%s\": %s,\n", x, s_error ? "false" : "true")
+
+static void test_eth(void) {
+  struct mg_tcpip_if ifp;
+  struct mg_str raw, pay;
+  enum mg_l2proto proto;
+  size_t len;
+  uint8_t frame[64];
+
+  {  // Plain Ethernet frame is accepted
+    uint8_t payload[] = {1, 2, 3, 4};
+    reset_if(&ifp);
+    mg_l2_init(&ifp);
+    MG_DEBUG(("MTU: %u, frame size: %u", ifp.l2mtu, ifp.framesize));
+    ASSERT(ifp.l2mtu != 0);
+    ASSERT(ifp.framesize != 0);
+    len = mk_eth(frame, s_mac, 0x0800, payload, sizeof(payload));
+    raw = mg_str_n((char *) frame, len);
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == true);
+    ASSERT(proto == MG_TCPIP_L2PROTO_IPV4);
+    ASSERT(pay.len == sizeof(payload));
+    ASSERT(memcmp(pay.buf, payload, sizeof(payload)) == 0);
+  }
+  {  // Unknown Ethernet type is discarded
+    uint8_t payload[] = {1, 2, 3, 4};
+    char sentinel[] = "discard";
+    reset_if(&ifp);
+    mg_l2_init(&ifp);
+    len = mk_eth(frame, s_mac, 0x1234, payload, sizeof(payload));
+    raw = mg_str_n((char *) frame, len);
+    pay = mg_str_n(sentinel, sizeof(sentinel));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(proto == MG_TCPIP_L2PROTO_ARP);
+  }
+}
+
+static void test_mac(void) {
+  struct mg_tcpip_if ifp;
+  struct mg_str raw, pay;
+  enum mg_l2proto proto;
+  size_t len;
+  uint8_t frame[64];
+
+  {  // MAC check accepts frames addressed to us
+    uint8_t payload[] = {1, 2, 3, 4};
+    reset_if(&ifp);
+    ifp.enable_mac_check = true;
+    mg_l2_init(&ifp);
+    len = mk_eth(frame, s_mac, 0x0800, payload, sizeof(payload));
+    raw = mg_str_n((char *) frame, len);
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == true);
+    ASSERT(proto == MG_TCPIP_L2PROTO_IPV4);
+    ASSERT(pay.len == sizeof(payload));
+    ASSERT(memcmp(pay.buf, payload, sizeof(payload)) == 0);
+  }
+  {  // MAC check discards alien unicast frames
+    uint8_t payload[] = {1, 2, 3, 4}, dst[6] = {1, 1, 1, 1, 1, 1};
+    char sentinel[] = "discard";
+    reset_if(&ifp);
+    ifp.enable_mac_check = true;
+    mg_l2_init(&ifp);
+    len = mk_eth(frame, dst, 0x0800, payload, sizeof(payload));
+    raw = mg_str_n((char *) frame, len);
+    pay = mg_str_n(sentinel, sizeof(sentinel));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(proto == MG_TCPIP_L2PROTO_ARP);
+    ASSERT(pay.buf == sentinel);
+    ASSERT(pay.len == sizeof(sentinel));
+  }
+}
+
+static void test_fcs(void) {
+  struct mg_tcpip_if ifp;
+  struct mg_str raw, pay;
+  enum mg_l2proto proto;
+  size_t len;
+  uint8_t frame[64];
+
+  {  // verify add_fcs() stores the CRC bytes in the proper order
+    // (internal consistency test)
+    uint8_t payload[] = {1, 2, 3, 4};
+    uint8_t fcs[] = {0xf4, 0xd4, 0x37, 0xf6};
+    len = add_fcs(frame, mk_eth(frame, s_mac, 0x0800, payload,
+                                sizeof(payload)));
+    ASSERT(memcmp(frame + len - sizeof(fcs), fcs, sizeof(fcs)) == 0);
+  }
+  {  // FCS check strips a valid CRC
+    uint8_t payload[] = {1, 2, 3, 4};
+    reset_if(&ifp);
+    ifp.enable_fcs_check = true;
+    mg_l2_init(&ifp);
+    len = add_fcs(frame, mk_eth(frame, s_mac, 0x0800, payload,
+                                sizeof(payload)));
+    raw = mg_str_n((char *) frame, len);
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == true);
+    ASSERT(proto == MG_TCPIP_L2PROTO_IPV4);
+    ASSERT(pay.len == sizeof(payload));
+    ASSERT(memcmp(pay.buf, payload, sizeof(payload)) == 0);
+  }
+  {  // FCS check rejects a bad CRC
+    uint8_t payload[] = {1, 2, 3, 4};
+    char sentinel[] = "discard";
+    reset_if(&ifp);
+    ifp.enable_fcs_check = true;
+    mg_l2_init(&ifp);
+    len = add_fcs(frame, mk_eth(frame, s_mac, 0x0800, payload,
+                                sizeof(payload)));
+    frame[len - 1] ^= 1;
+    raw = mg_str_n((char *) frame, len);
+    pay = mg_str_n(sentinel, sizeof(sentinel));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(proto == MG_TCPIP_L2PROTO_ARP);
+    ASSERT(pay.buf == sentinel);
+    ASSERT(pay.len == sizeof(sentinel));
+  }
+  {  // Disabled FCS check leaves the CRC in payload
+    uint8_t payload[] = {1, 2, 3, 4};
+    reset_if(&ifp);
+    mg_l2_init(&ifp);
+    len = add_fcs(frame, mk_eth(frame, s_mac, 0x0800, payload,
+                                sizeof(payload)));
+    raw = mg_str_n((char *) frame, len);
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == true);
+    ASSERT(proto == MG_TCPIP_L2PROTO_IPV4);
+    ASSERT(pay.len == sizeof(payload) + sizeof(uint32_t));
+    ASSERT(memcmp(pay.buf, payload, sizeof(payload)) == 0);
+  }
+}
+
+static void test_vlan(void) {
+  struct mg_tcpip_if ifp;
+  struct mg_str raw, pay;
+  enum mg_l2proto proto;
+  size_t len;
+  uint8_t frame[64];
+
+  {  // Configured VLAN accepts matching tagged frames
+    uint8_t payload[] = {5, 6, 7, 8};
+    reset_if(&ifp);
+    ifp.l2data.eth.vlan_id = 123;
+    mg_l2_init(&ifp);
+    MG_DEBUG(("MTU: %u, frame size: %u", ifp.l2mtu, ifp.framesize));
+    ASSERT(ifp.l2mtu != 0);
+    ASSERT(ifp.framesize != 0);
+    len = mk_vlan(frame, s_mac, 123, 0x86dd, payload, sizeof(payload));
+    raw = mg_str_n((char *) frame, len);
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == true);
+    ASSERT(proto == MG_TCPIP_L2PROTO_IPV6);
+    ASSERT(pay.len == sizeof(payload));
+    ASSERT(memcmp(pay.buf, payload, sizeof(payload)) == 0);
+  }
+  {  // Configured VLAN rejects non-matching tags
+    uint8_t payload[] = {5, 6, 7, 8};
+    char sentinel[] = "discard";
+    reset_if(&ifp);
+    ifp.l2data.eth.vlan_id = 123;
+    mg_l2_init(&ifp);
+    len = mk_vlan(frame, s_mac, 124, 0x86dd, payload, sizeof(payload));
+    raw = mg_str_n((char *) frame, len);
+    pay = mg_str_n(sentinel, sizeof(sentinel));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(proto == MG_TCPIP_L2PROTO_ARP);
+    ASSERT(pay.buf == sentinel);
+    ASSERT(pay.len == sizeof(sentinel));
+  }
+  {  // Tagged frames are rejected when no VLAN is configured
+    uint8_t payload[] = {5, 6, 7, 8};
+    reset_if(&ifp);
+    mg_l2_init(&ifp);
+    len = mk_vlan(frame, s_mac, 123, 0x86dd, payload, sizeof(payload));
+    raw = mg_str_n((char *) frame, len);
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(proto == MG_TCPIP_L2PROTO_ARP);
+  }
+}
+
+int main(void) {
+  s_error = false;
+  test_eth();
+  DASHBOARD("eth");
+
+  s_error = false;
+  test_mac();
+  DASHBOARD("mac");
+
+  s_error = false;
+  test_fcs();
+  DASHBOARD("fcs");
+
+  s_error = false;
+  test_vlan();
+  printf("HEALTH_DASHBOARD\t\"vlan\": %s\n", s_error ? "false" : "true");
+
+#ifdef NO_ABORT
+  if (s_abort != 0) return EXIT_FAILURE;
+#endif
+
+  printf("SUCCESS. Total tests: %d\n", s_num_tests);
+  return EXIT_SUCCESS;
+}

test/fuzz.c

@@ -23,6 +23,52 @@ static void fn(struct mg_connection *c, int ev, void *ev_data) {
   }
 }
 
+// deduplicate layer-3 mocking among layer-2s
+struct fuzz_l3_state {
+  size_t ip_proto, udp_port;
+  size_t ip6_next, icmp6_type;
+};
+
+static void fuzz_ip4(void *buf, size_t len, struct fuzz_l3_state *st) {
+  if (len >= sizeof(struct ip)) {
+    uint8_t ip_protos[] = {1, 6, 17}; // ICMP, TCP, UDP
+    struct ip *ip4 = (struct ip *) buf;
+    ip4->ver = (uint8_t) ((ip4->ver & ~0xf0) | (4 << 4));
+    // send all handled IP protos, then 2 random ones
+    if (st->ip_proto >= (sizeof(ip_protos) / sizeof(ip_protos[0]) + 2)) st->ip_proto = 0;
+    if (st->ip_proto < (sizeof(ip_protos) / sizeof(ip_protos[0]))) ip4->proto = ip_protos[st->ip_proto++];
+    if (ip4->proto == 1) { // ICMP
+    } else if (ip4->proto == 6) { // TCP
+    } else if (ip4->proto == 17 && len >= sizeof(struct ip) + sizeof(struct udp)) { // UDP
+      uint16_t udp_ports[] = {67, 68}; // DHCP server and client
+      struct udp *udp = (struct udp *) (ip4 + 1);
+      // send all handled UDP ports, then 2 random ones
+      if (st->udp_port >= (sizeof(udp_ports) / sizeof(udp_ports[0]) + 2)) st->udp_port = 0;
+      if (st->udp_port < (sizeof(udp_ports) / sizeof(udp_ports[0]))) udp->dport = mg_htons(udp_ports[st->udp_port++]);
+    }
+  }
+}
+
+static void fuzz_ip6(void *buf, size_t len, struct fuzz_l3_state *st) {
+  if (len >= sizeof(struct ip6)) {
+    uint8_t ip6_protos[] = {6, 17, 58}; // TCP, UDP, ICMPv6
+    struct ip6 *ip6 = (struct ip6 *) buf;
+    ip6->ver = (uint8_t) ((ip6->ver & ~0xf0) | (6 << 4));
+    // send all handled IPv6 "next headers", then 2 random ones
+    if (st->ip6_next >= (sizeof(ip6_protos) / sizeof(ip6_protos[0]) + 2)) st->ip6_next = 0;
+    if (st->ip6_next < (sizeof(ip6_protos) / sizeof(ip6_protos[0]))) ip6->next = ip6_protos[st->ip6_next++];
+    if (ip6->next == 6) { // TCP
+    } else if (ip6->next == 17) { // UDP
+    } else if (ip6->next == 58 && len >= sizeof(struct ip6) + sizeof(struct icmp6)) { // ICMPv6
+      uint8_t icmp6_types[] = {128, 134, 135, 136}; // Echo Request, RA, NS, NA
+      struct icmp6 *icmp6 = (struct icmp6 *) (ip6 + 1);
+      // send all handled ICMPv6 types, then 2 random ones
+      if (st->icmp6_type >= (sizeof(icmp6_types) / sizeof(icmp6_types[0]) + 2)) st->icmp6_type = 0;
+      if (st->icmp6_type < (sizeof(icmp6_types) / sizeof(icmp6_types[0]))) icmp6->type = icmp6_types[st->icmp6_type++];
+    }
+  }
+}
+
 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
   mg_log_set(MG_LL_INFO);
 
@@ -94,21 +140,26 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
 
   // Test built-in TCP/IP stack
   if (size > 0) {
+    static size_t t;
     struct mg_tcpip_if mif = {.ip = 1,
                               .mask = 255,
                               .gw = 1,
                               .gw_ready = true,
                               .state = MG_TCPIP_STATE_READY,
 #if MG_ENABLE_IPV6
-                              .ip6[0] = 1;
-                              .prefix[0] = 1;
-                              .prefix_len = 64;
-                              .gw6[0] = 1;
-                              .gw6_ready = true;
-                              .state6 = MG_TCPIP_STATE_READY;  // so mg_send() works and RS stops
+                              .ip6[0] = 1,
+                              .prefix[0] = 1,
+                              .prefix_len = 64,
+                              .gw6[0] = 1,
+                              .gw6_ready = true,
+                              .state6 = MG_TCPIP_STATE_READY,  // so mg_send() works and RS stops
 #endif
                               .driver = &mg_tcpip_driver_mock};
     struct mg_mgr mgr;
+
+    if (t >= MG_TCPIP_L2_USER) t = 0; // defined in l2.h
+    mif.l2type = (enum mg_l2type) t++; // configure to a L2 type
+
     mg_mgr_init(&mgr);
     mg_tcpip_init(&mgr, &mif);
 
@@ -116,56 +167,186 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
     void *pkt = malloc(size);
     struct eth *eth = (struct eth *) pkt;
     memcpy(pkt, data, size);
-    if (size > sizeof(*eth)) {
-      static size_t i;
+    if ((mif.l2type == MG_TCPIP_L2_ETH || mif.l2type == MG_TCPIP_L2_PPPoE) && size > sizeof(*eth)) {
+      static size_t i, v;
+      static struct fuzz_l3_state l3;
+      uint8_t *ethpay = (uint8_t *) (eth + 1);
+      size_t ethhdrsz = sizeof(*eth);
+      uint16_t etype;
       // eth_types[] exists in l2_eth.c
       memcpy(eth->dst, mif.mac, 6);  // Set valid destination MAC
       // send all handled eth types, then 2 random ones
       if (i >= (sizeof(eth_types) / sizeof(eth_types[0]) + 2)) i = 0;
       if (i < (sizeof(eth_types) / sizeof(eth_types[0]))) eth->type = mg_htons(eth_types[i++]);
+      etype = mg_ntohs(eth->type);
+      if (v >= 10) v = 0; // 802.1Q tag 3 out of 10 frames
+      if (v < 3) mif.l2data.eth.vlan_id = 123;
+      if (size > sizeof(*eth) + sizeof(struct qtag)) {
+        struct qtag *qtag = (struct qtag *) &eth->type;
+        if (v == 0) {
+          // v=0: configured for VLAN 123, untagged frame, discard path
+        } else if (v == 1) {
+          // v=1: configured for VLAN 123, tagged VLAN 123, accept path
+          qtag->tpid = mg_htons(0x8100);
+          qtag->tci = mg_htons(123);
+          MG_STORE_BE16(qtag + 1, etype);
+          ethhdrsz += sizeof(*qtag);
+          ethpay += sizeof(*qtag);
+        } else if (v == 2) {
+          // v=2: configured for VLAN 123, tagged random VLAN, mismatch path
+          qtag->tpid = mg_htons(0x8100);
+          MG_STORE_BE16(qtag + 1, etype);
+          ethhdrsz += sizeof(*qtag);
+          ethpay += sizeof(*qtag);
+        } else if (v == 3) {
+          // v=3: unconfigured VLAN, tagged frame, discard path
+          qtag->tpid = mg_htons(0x8100);
+          MG_STORE_BE16(qtag + 1, etype);
+          ethhdrsz += sizeof(*qtag);
+          ethpay += sizeof(*qtag);
+        } // else unconfigured VLAN, untagged frame, normal path
+      }
+      ++v;
+      if (etype == 0x8863 && size > (ethhdrsz + sizeof(struct pppoe))) { // PPPoE disc
+        static size_t j;
+        uint8_t pppoe_codes[] = {MG_PPPoE_PADO, MG_PPPoE_PADS, MG_PPPoE_PADT}; // defined in l2_ppp.c
+        struct pppoe *pppoe = (struct pppoe *) ethpay;
+        pppoe->vertype = 0x11;
+        // send all handled PPPoE codes, then 2 random ones
+        if (j >= (sizeof(pppoe_codes) / sizeof(pppoe_codes[0]) + 2)) j = 0;
+        if (j < (sizeof(pppoe_codes) / sizeof(pppoe_codes[0]))) pppoe->code = (pppoe_codes[j++]);
+        if (pppoe->code == MG_PPPoE_PADO) {
+          static size_t k;
+          // send id=0, then 2 random ids
+          if (k >= 3) k = 0;
+          if (k == 0) pppoe->id = 0;
+          ++k;
+        } else if (pppoe->code == MG_PPPoE_PADS) {
+          static size_t k;
+          // send id=x, then 2 random ids
+          if (k >= 3) k = 0;
+          if (k == 0) pppoe->id = 0x1234;
+          ++k;
+        } else if (pppoe->code == MG_PPPoE_PADT) { // keep separate so they do not correlate too much
+          static size_t k;
+          // send id=x, then 2 random ids
+          if (k >= 3) k = 0;
+          if (k == 0) pppoe->id = 0x1234;
+          ++k;
+        }
+      } else if (etype == 0x8864 && size > (ethhdrsz + sizeof(struct pppoe))) { // PPPoE sess
+        // PPP rx is covered via HDLC too; PPPoE tx wrapping may remain unexercised.
+        struct pppoe *pppoe = (struct pppoe *) ethpay;
+        static size_t k, l;
+        // send code=0, then 2 random codes
+        if (k >= 3) k = 0;
+        if (k == 0)  {
+          static size_t m;
+          pppoe->code = 0;
+          // send id=x, then 2 random ids
+          if (m >= 3) m = 0;
+          if (m == 0) pppoe->id = 0x1234;
+          ++m;
+        }
+        ++k;
+        // set s_state to valid and invalid
+        if (l >= 2) l = 0;
+        if (l == 0) s_state = MG_PPPoE_ST_SESS; // defined in l2_ppp.c
+        if (l == 1) s_state = MG_PPPoE_ST_REQ;
+        ++l;
+        // PPP exercised in other block
+      }
       // build proper layer-3 datagrams, to be able to exercise layers above
-      if (eth->type == mg_htons(0x800) && size > (sizeof(*eth) + sizeof(struct ip))) {             // IPv4
-        static size_t j;
-        uint8_t ip_protos[] = {1, 6, 17}; // ICMP, TCP, UDP
-        struct ip *ip4 = (struct ip *) (eth + 1);
-        ip4->ver = (ip4->ver & ~0xf0) | (4 << 4);
-        // send all handled IP protos, then 2 random ones
-        if (j >= (sizeof(ip_protos) / sizeof(ip_protos[0]) + 2)) j = 0;
-        if (j < (sizeof(ip_protos) / sizeof(ip_protos[0]))) ip4->proto = (ip_protos[j++]);
-        if (ip4->proto == 1) { // ICMP
-        } else if (ip4->proto == 6) { // TCP
-        } else if (ip4->proto == 17) { // UDP
-          if (size > (sizeof(*eth) + sizeof(struct ip) + sizeof(struct udp))) {
-            static size_t k;
-            uint16_t udp_ports[] = {67, 68}; // DHCP server and client
-            struct udp *udp = (struct udp *) (ip4 + 1);
-            // send all handled UDP ports, then 2 random ones
-            if (k >= (sizeof(udp_ports) / sizeof(udp_ports[0]) + 2)) k = 0;
-            if (k < (sizeof(udp_ports) / sizeof(udp_ports[0]))) udp->dport = mg_htons(udp_ports[k++]);
-          }
-        }
-      } else if (eth->type == mg_htons(0x806)) {      // ARP
+      else if (etype == 0x800 && size > (ethhdrsz + sizeof(struct ip))) {         // IPv4
+        fuzz_ip4(ethpay, size - ethhdrsz, &l3);
+      } else if (etype == 0x806) {      // ARP
 
-      } else if (eth->type == mg_htons(0x86dd) && size > (sizeof(*eth) + sizeof(struct ip6))) {     // IPv6
-        static size_t j;
-        uint8_t ip6_protos[] = {6, 17, 58}; // TCP, UDP, ICMPv6
-        struct ip6 *ip6 = (struct ip6 *) (eth + 1);
-        ip6->ver = (ip6->ver & ~0xf0) | (6 << 4);
-        // send all handled IPv6 "next headers", then 2 random ones
-        if (j >= (sizeof(ip6_protos) / sizeof(ip6_protos[0]) + 2)) j = 0;
-        if (j < (sizeof(ip6_protos) / sizeof(ip6_protos[0]))) ip6->next = (ip6_protos[j++]);
-        if (ip6->next == 6) { // TCP
-        } else if (ip6->next == 17) { // UDP
-        } else if (ip6->next == 58) { // ICMPv6
-          if (size >= (sizeof(*eth) + sizeof(struct ip6) + sizeof(struct icmp6))) {
-            static size_t k;
-            uint8_t icmp6_types[] = {128, 134, 135, 136}; // Echo Request, RA, NS, NA
-            struct icmp6 *icmp6 = (struct icmp6 *) (ip6 + 1);
-            // send all handled ICMPv6 types, then 2 random ones
-            if (k >= (sizeof(icmp6_types) / sizeof(icmp6_types[0]) + 2)) k = 0;
-            if (k < (sizeof(icmp6_types) / sizeof(icmp6_types[0]))) icmp6->type = icmp6_types[k++];
-          }
+      } else if (etype == 0x86dd && size > (ethhdrsz + sizeof(struct ip6))) {     // IPv6
+        fuzz_ip6(ethpay, size - ethhdrsz, &l3);
+      }
+    } else if (mif.l2type == MG_TCPIP_L2_PPP && size > (sizeof(struct hdlc_) + sizeof(struct ppp) + 2)) {
+      static size_t i;
+      static struct fuzz_l3_state l3;
+      uint16_t ppp_protos[] = {
+          MG_PPP_PROTO_LCP, MG_PPP_PROTO_IPCP, MG_PPP_PROTO_IP, MG_PPP_PROTO_IPV6CP, MG_PPP_PROTO_IPV6
+      };
+      struct hdlc_ *hdlc = (struct hdlc_ *) pkt;
+      struct ppp *ppp = (struct ppp *) (hdlc + 1);
+      size_t len = size - sizeof(*hdlc) - sizeof(*ppp) - 2;
+      hdlc->addr = MG_PPP_ADDR;
+      hdlc->ctrl = MG_PPP_CTRL;
+      s_lcpup = true;
+      // send all handled PPP protocols, then 2 random ones
+      if (i >= (sizeof(ppp_protos) / sizeof(ppp_protos[0]) + 2)) i = 0;
+      if (i < (sizeof(ppp_protos) / sizeof(ppp_protos[0]))) ppp->proto = mg_htons(ppp_protos[i++]);
+      if (ppp->proto == mg_htons(MG_PPP_PROTO_LCP) && len >= sizeof(struct lcp)) {
+        static size_t j, k;
+        uint8_t lcp_codes[] = {MG_PPP_LCP_CFG_REQ, MG_PPP_LCP_CFG_ACK, MG_PPP_LCP_CFG_TERM_REQ, MG_PPP_LCP_ECHO_REQ};
+        struct lcp *lcp = (struct lcp *) (ppp + 1);
+        // send all handled LCP codes, then 2 random ones
+        if (j >= (sizeof(lcp_codes) / sizeof(lcp_codes[0]) + 2)) j = 0;
+        if (j < (sizeof(lcp_codes) / sizeof(lcp_codes[0]))) lcp->code = lcp_codes[j++];
+        // send valid length, then 2 random lengths
+        if (k >= 3) k = 0;
+        if (k == 0) lcp->len = mg_htons((uint16_t) sizeof(*lcp));
+        ++k;
+      } else if (ppp->proto == mg_htons(MG_PPP_PROTO_IPCP) && len >= 10) {
+        static size_t j, k, m;
+        uint8_t ipcp_codes[] = {MG_PPP_IPCP_CFG_REQ, MG_PPP_IPCP_CFG_ACK, MG_PPP_IPCP_CFG_NACK, MG_PPP_IPCP_CFG_REJECT};
+        struct ipcp *ipcp = (struct ipcp *) (ppp + 1);
+        uint8_t *opts = (uint8_t *) (ipcp + 1);
+        // send all handled IPCP codes, then 2 random ones
+        if (j >= (sizeof(ipcp_codes) / sizeof(ipcp_codes[0]) + 2)) j = 0;
+        if (j < (sizeof(ipcp_codes) / sizeof(ipcp_codes[0]))) ipcp->code = ipcp_codes[j++];
+        // send valid length, then 2 random lengths
+        if (m >= 3) m = 0;
+        if (m == 0) ipcp->len = mg_htons(10);
+        ++m;
+        // send valid IPADDR option, then 2 random option types
+        if (k >= 3) k = 0;
+        if (k == 0) {
+          static size_t l;
+          opts[0] = MG_PPP_IPCP_OPT_IPADDR;
+          // for valid option type, send valid length, then random length
+          if (l >= 2) l = 0;
+          if (l == 0) opts[1] = 6;
+          ++l;
         }
+        ++k;
+      } else if (ppp->proto == mg_htons(MG_PPP_PROTO_IP) && len >= sizeof(struct ip)) {
+        fuzz_ip4(ppp + 1, len, &l3);
+      } else if (ppp->proto == mg_htons(MG_PPP_PROTO_IPV6CP) && len >= 14) {
+        static size_t j, k, m;
+        uint8_t ipv6cp_codes[] = {MG_PPP_IPV6CP_CFG_REQ, MG_PPP_IPV6CP_CFG_ACK, MG_PPP_IPV6CP_CFG_NACK, MG_PPP_IPV6CP_CFG_REJECT};
+        struct ipv6cp *ipv6cp = (struct ipv6cp *) (ppp + 1);
+        uint8_t *opts = (uint8_t *) (ipv6cp + 1);
+        // send all handled IPV6CP codes, then 2 random ones
+        if (j >= (sizeof(ipv6cp_codes) / sizeof(ipv6cp_codes[0]) + 2)) j = 0;
+        if (j < (sizeof(ipv6cp_codes) / sizeof(ipv6cp_codes[0]))) ipv6cp->code = ipv6cp_codes[j++];
+        // send valid length, then 2 random lengths
+        if (m >= 3) m = 0;
+        if (m == 0) ipv6cp->len = mg_htons(14);
+        ++m;
+        // send valid IFCID option, then 2 random option types
+        if (k >= 3) k = 0;
+        if (k == 0) {
+          static size_t l;
+          opts[0] = MG_PPP_IPV6CP_OPT_IFCID;
+          // for valid option type, send valid length, then random length
+          if (l >= 2) l = 0;
+          if (l == 0) {
+            static size_t o;
+            opts[1] = 10;
+            // for valid option length, send non-zero IFCID, then 2 random IFCIDs
+            if (o >= 3) o = 0;
+            if (o == 0) opts[9] = 1;
+            ++o;
+          }
+          ++l;
+        }
+        ++k;
+      } else if (ppp->proto == mg_htons(MG_PPP_PROTO_IPV6) && len >= sizeof(struct ip6)) {
+        fuzz_ip6(ppp + 1, len, &l3);
       }
     }
 
@@ -175,8 +356,11 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
 #endif
     mg_tcpip_rx(&mif, pkt, size);
 
+    // prior actions may have had consequences on link state
+    mif.state = MG_TCPIP_STATE_READY;
     // Test HTTP serving (via our built-in TCP/IP stack)
-    const char *url = "http://localhost:12345";
+    const char *url = "http://localhost:12345"; // internally resolves
+    // creates a connection and sends SYN via the router, unless OOM
     struct mg_connection *c = mg_http_connect(&mgr, url, fn, NULL);
     mg_iobuf_add(&c->recv, 0, data, size);
     c->pfn(c, MG_EV_READ, NULL); // manually invoke protocol event handler

test/mip_test.c

@@ -110,7 +110,8 @@ static void ph(struct mg_connection *c, int ev, void *ev_data) {
 }
 
 static void fn(struct mg_connection *c, int ev, void *ev_data) {
-  (void) c, (void) ev, (void) ev_data;
+  if (ev == MG_EV_ACCEPT) ASSERT(mg_dscp(c, MG_DSCP_AF(4, 1)));
+  (void) ev_data;
 }
 
 static void tcpclosure_fn(struct mg_connection *c, int ev, void *ev_data) {
@@ -158,7 +159,7 @@ static void frag_send_fn(struct mg_connection *c, int ev, void *ev_data) {
     }
   } else if (ev == MG_EV_WRITE) {
     // Checking TCP segment sizes (ev_data points to the TCP payload length)
-    ASSERT(*(int *) ev_data == s_seg_sizes[s_seg_sent++]);
+    ASSERT(*(long *) ev_data == s_seg_sizes[s_seg_sent++]);
   }
   (void) c, (void) ev_data;
 }
@@ -298,7 +299,7 @@ static void init_tests(struct mg_mgr *mgr, struct eth *e, struct ipp *ipp,
     mif->ip = mg_htonl(0x1000000);
     mif->gw = mg_htonl(0x1000000);
     mif->gw_ready = true;
-    mif->mask = 255;  // use router, to avoid firing an ARP request
+    mif->mask = mg_htonl(0xff000000);   // use router, avoid firing ARP request
     mif->state = MG_TCPIP_STATE_READY;  // so mg_send() works and DHCP stops
   }
   mg_tcpip_init(mgr, mif);
@@ -306,7 +307,7 @@ static void init_tests(struct mg_mgr *mgr, struct eth *e, struct ipp *ipp,
   // setting the Ethernet header
   memset(e, 0, sizeof(*e));
   memcpy(e->dst, mif->mac, 6 * sizeof(uint8_t));
-  e->type = mg_htons(ipp->ip4 != NULL ? 0x800 : 0x86dd);
+  e->type = mg_htons((uint16_t)(ipp->ip4 != NULL ? 0x800 : 0x86dd));
 
   // setting the IP header
 #if MG_ENABLE_IPV6
@@ -499,8 +500,11 @@ static void test_tcp_basics(bool ipv6) {
   if (ipv6) {
     ASSERT(i6->src[0] == mg_htonll(0x100000000000000) && i6->src[1] == 0 &&
            i6->dst[0] == mg_htonll(0x200000000000000) && i6->dst[1] == 0);
+    ASSERT((uint8_t) (((i6->ver & 15) << 2) | (i6->label[0] >> 6)) ==
+           MG_DSCP_AF(4, 1));
   } else {
     ASSERT(i->src == mg_htonl(0x1000000) && i->dst == mg_htonl(0x2000000));
+    ASSERT(i->tos == (MG_DSCP_AF(4, 1) << 2));
   }
 
   // segment with seq_no way out of window
@@ -1125,8 +1129,11 @@ static void test_tcp(bool ipv6) {
 }
 
 static void udp_fn(struct mg_connection *c, int ev, void *ev_data) {
-  if (ev == MG_EV_READ && c->recv.len == 2 && c->recv.buf[0] == 'p')
+  if (ev == MG_EV_OPEN) {
+    ASSERT(mg_dscp(c, MG_DSCP_AF(4, 1)));
+  } else if (ev == MG_EV_READ && c->recv.len == 2 && c->recv.buf[0] == 'p') {
     mg_send(c, "P90", 3);
+  }
   (void) ev_data;
 }
 
@@ -1221,9 +1228,12 @@ static void test_udp(bool ipv6) {
   if (ipv6) {
     ASSERT(i6->src[0] == mg_htonll(0x100000000000000) && i6->src[1] == 0 &&
            i6->dst[0] == mg_htonll(0x200000000000000) && i6->dst[1] == 0);
+    ASSERT((uint8_t) (((i6->ver & 15) << 2) | (i6->label[0] >> 6)) ==
+           MG_DSCP_AF(4, 1));
     ASSERT(udp6csum_ok(i6, u));
   } else {
     ASSERT(i->src == mg_htonl(0x1000000) && i->dst == mg_htonl(0x2000000));
+    ASSERT(i->tos == (MG_DSCP_AF(4, 1) << 2));
     ASSERT(udpcsum_ok(i, u));
   }
 

test/mip_x_test.c

@@ -1,7 +1,7 @@
 #define MG_ENABLE_TCPIP 1
 #define MG_ENABLE_TCPIP_DRIVER_INIT 0
 
-#define FETCH_BUF_SIZE (16 * 1024)
+#define FETCH_BUF_SIZE (32 * 1024)
 
 #include "mongoose.c"
 
@@ -196,6 +196,7 @@ static int fetch(struct mg_mgr *mgr, char *buf, const char *url,
   va_list ap;
   mg_mgr_poll(mgr, 0);  // update ifp->now to avoid ARP lookup using an old
                         // timestamp (from an ancient call in other test)
+  mg_mgr_poll(mgr, 0);  // (prior idling collects lots of frames)
   c = mg_http_connect(mgr, url, fcb, &fd);
   ASSERT(c != NULL);
   va_start(ap, fmt);
@@ -355,12 +356,13 @@ static void test_mqtt_connsubpub(struct mg_mgr *mgr) {
   data.url = strdup(MQTT_URL);
 #endif
 #endif // MG_TLS
-  mg_mgr_poll(mgr, 0); // update interface timing
+  mg_mgr_poll(mgr, 0); // update interface timing (*)
+  mg_mgr_poll(mgr, 0);
   s_conn = mg_mqtt_connect(mgr, data.url, &opts, mqtt_fn, &data);
   ASSERT(s_conn != NULL);
   for (int i = 0; i < 1000 && s_conn != NULL && !s_conn->is_closing; i++) {
     mg_mgr_poll(mgr, 0);
-    usleep(10000);  // 10 ms. Slow down poll loop to ensure packets transit
+    usleep(5000);  // 5 ms (*) See fetch() above for reasons
   }
   ASSERT(data.passed);
   mg_mgr_poll(mgr, 0);
@@ -400,11 +402,13 @@ static void test_mqtt_connsubpub(struct mg_mgr *mgr) {
 #endif
 #endif // MG_TLS
   data.passed = false;
+  mg_mgr_poll(mgr, 0); // update interface timing (*)
+  mg_mgr_poll(mgr, 0);
   s_conn = mg_mqtt_connect(mgr, data.url, &opts, mqtt_fn, &data);
   ASSERT(s_conn != NULL);
   for (int i = 0; i < 1000 && s_conn != NULL && !s_conn->is_closing; i++) {
     mg_mgr_poll(mgr, 0);
-    usleep(10000);  // 10 ms. Slow down poll loop to ensure packets transit
+    usleep(5000);  // 5 ms (*) See fetch() above for reasons
   }
   ASSERT(data.passed);
   mg_mgr_poll(mgr, 0);

test/port_tap_bridge.c

@@ -10,6 +10,7 @@
 #include <fcntl.h>
 #include <sys/ioctl.h>
 #include <sys/poll.h>
+#include <signal.h>
 
 #ifndef __OpenBSD__
 #include <linux/if.h>
@@ -20,7 +21,7 @@
 #include <net/if_types.h>
 #endif
 
-static int s_signo;
+static volatile sig_atomic_t s_signo;
 void signal_handler(int signo) {
   s_signo = signo;
 }
@@ -49,6 +50,8 @@ int main(void) {
     return EXIT_FAILURE;
   }
   printf("Opened TAP interface: %s\n", iface);
+  signal(SIGINT, signal_handler);
+  signal(SIGTERM, signal_handler);
 
   int sockfd;
   struct sockaddr_in tap_addr, port_addr;
@@ -97,8 +100,9 @@ int main(void) {
         }
 				break;
 			}
-		} while (result >= 0);
-    printf("looks like we got an error here... should I quit ? Waiting for CTRL-C\n");
+		} while (result >= 0 && s_signo == 0);
+    if (result < 0)
+      printf("looks like we got an error here... should I quit ? Waiting for CTRL-C\n");
 	} 
   close(sockfd);
   close(fd);

test/ppp_test.c

@@ -0,0 +1,431 @@
+#define MG_ENABLE_TCPIP 1
+#define MG_ENABLE_TCPIP_DRIVER_INIT 0
+
+#include "mongoose.c"
+#include "driver_mock.c"
+
+static int s_num_tests = 0;
+static bool s_error = false;
+
+#ifdef NO_ABORT
+static int s_abort = 0;
+#define ABORT() ++s_abort, s_error = true
+#else
+#ifdef NO_SLEEP_ABORT
+#define ABORT() abort()
+#else
+#define ABORT()                       \
+  sleep(2); /* 2s, GH print reason */ \
+  abort();
+#endif
+#endif
+
+#define ASSERT(expr)                                            \
+  do {                                                          \
+    s_num_tests++;                                              \
+    if (!(expr)) {                                              \
+      printf("FAILURE %s:%d: %s\n", __FILE__, __LINE__, #expr); \
+      fflush(stdout);                                           \
+      ABORT();                                                  \
+    }                                                           \
+  } while (0)
+
+static const uint8_t s_mac[6] = {2, 3, 4, 5, 6, 7};
+static const uint8_t s_src[6] = {8, 9, 10, 11, 12, 13};
+
+static uint8_t s_tx[2048];
+
+static void init_if(struct mg_tcpip_if *ifp, enum mg_l2type type) {
+  memset(ifp, 0, sizeof(*ifp));
+  memcpy(ifp->mac, s_mac, sizeof(s_mac));
+  ifp->driver = &mg_tcpip_driver_mock;
+  ifp->l2type = type;
+  ifp->tx.buf = (char *) s_tx;
+  ifp->tx.len = sizeof(s_tx);
+  mg_l2_init(ifp);
+}
+
+static size_t mk_ppp(uint8_t *buf, uint16_t proto, const void *payload,
+                     size_t len) {
+  struct hdlc_ *hdlc = (struct hdlc_ *) buf;
+  struct ppp *ppp = (struct ppp *) (hdlc + 1);
+  hdlc->addr = MG_PPP_ADDR;
+  hdlc->ctrl = MG_PPP_CTRL;
+  ppp->proto = mg_htons(proto);
+  memcpy(ppp + 1, payload, len);
+  memset((uint8_t *) (ppp + 1) + len, 0, 2);
+  return sizeof(*hdlc) + sizeof(*ppp) + len + 2;
+}
+
+static void *ppp_payload(uint8_t *frame) {
+  return (struct ppp *) ((struct hdlc_ *) frame + 1) + 1;
+}
+
+static void test_fcs(void) {
+  struct mg_tcpip_if ifp;
+  uint8_t frame[] = {0xff, 0x03, 0x00, 0x21, 1, 2, 3, 4, 0, 0};
+  uint8_t fcs[] = {0xae, 0x77};
+  init_if(&ifp, MG_TCPIP_L2_PPP);
+  // PPP trailer stores the FCS bytes in the proper order
+  ASSERT(mg_l2_ppp_trailer(&ifp, 4, frame + sizeof(frame) - sizeof(fcs)) ==
+         sizeof(frame));
+  ASSERT(memcmp(frame + sizeof(frame) - sizeof(fcs), fcs, sizeof(fcs)) == 0);
+}
+
+static size_t mk_pppoe_disc(uint8_t *buf, uint8_t code, uint16_t id,
+                            const void *payload, size_t len) {
+  struct eth *eth = (struct eth *) buf;
+  struct pppoe *pppoe = (struct pppoe *) (eth + 1);
+  memcpy(eth->dst, s_mac, sizeof(eth->dst));
+  memcpy(eth->src, s_src, sizeof(eth->src));
+  eth->type = mg_htons(0x8863);
+  pppoe->vertype = 0x11;
+  pppoe->code = code;
+  pppoe->id = mg_htons(id);
+  pppoe->len = mg_htons((uint16_t) len);
+  if (len > 0) memcpy(pppoe + 1, payload, len);
+  return sizeof(*eth) + sizeof(*pppoe) + len;
+}
+
+static size_t mk_pppoe_sess(uint8_t *buf, uint16_t id, uint16_t proto,
+                            const void *payload, size_t len) {
+  struct eth *eth = (struct eth *) buf;
+  struct pppoe *pppoe = (struct pppoe *) (eth + 1);
+  struct ppp *ppp = (struct ppp *) (pppoe + 1);
+  memcpy(eth->dst, s_mac, sizeof(eth->dst));
+  memcpy(eth->src, s_src, sizeof(eth->src));
+  eth->type = mg_htons(0x8864);
+  pppoe->vertype = 0x11;
+  pppoe->code = 0;
+  pppoe->id = mg_htons(id);
+  pppoe->len = mg_htons((uint16_t) (sizeof(*ppp) + len));
+  ppp->proto = mg_htons(proto);
+  memcpy(ppp + 1, payload, len);
+  return sizeof(*eth) + sizeof(*pppoe) + sizeof(*ppp) + len;
+}
+
+static void test_lcp(void) {
+  uint8_t frame[64];
+  struct mg_tcpip_if ifp;
+  struct mg_str raw, pay;
+  enum mg_l2proto proto;
+
+  {  // LCP ACK brings PPP link up
+    struct lcp lcp = {MG_PPP_LCP_CFG_ACK, 1, mg_htons(sizeof(lcp))};
+    init_if(&ifp, MG_TCPIP_L2_PPP);
+    s_lcpup = false;
+    raw = mg_str_n((char *) frame,
+                   mk_ppp(frame, MG_PPP_PROTO_LCP, &lcp, sizeof(lcp)));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(s_lcpup == true);
+  }
+  {  // Short LCP frame is discarded
+    uint8_t lcp[] = {MG_PPP_LCP_CFG_ACK, 1};
+    init_if(&ifp, MG_TCPIP_L2_PPP);
+    s_lcpup = false;
+    raw = mg_str_n((char *) frame,
+                   mk_ppp(frame, MG_PPP_PROTO_LCP, lcp, sizeof(lcp)));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(s_lcpup == false);
+  }
+}
+
+static void test_ipcp(void) {
+  uint8_t frame[64];
+  struct mg_tcpip_if ifp;
+  struct mg_str raw, pay;
+  enum mg_l2proto proto;
+
+  {  // IPCP request with peer IP address is ACKed
+    uint8_t ipcp[] = {MG_PPP_IPCP_CFG_REQ, 1, 0, 10,
+                      MG_PPP_IPCP_OPT_IPADDR, 6, 192, 0, 2, 1};
+    uint32_t peer;
+    init_if(&ifp, MG_TCPIP_L2_PPP);
+    s_lcpup = true;
+    memcpy(&peer, ipcp + 6, sizeof(peer));
+    raw = mg_str_n((char *) frame,
+                   mk_ppp(frame, MG_PPP_PROTO_IPCP, ipcp, sizeof(ipcp)));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(ifp.gw == peer);
+    ASSERT(((struct ipcp *) ppp_payload(frame))->code == MG_PPP_IPCP_CFG_ACK);
+    ASSERT(ifp.nsent == 2);
+  }
+  {  // IPCP request without peer IP address is rejected
+    uint8_t ipcp[] = {MG_PPP_IPCP_CFG_REQ, 1, 0, 4};
+    init_if(&ifp, MG_TCPIP_L2_PPP);
+    s_lcpup = true;
+    raw = mg_str_n((char *) frame,
+                   mk_ppp(frame, MG_PPP_PROTO_IPCP, ipcp, sizeof(ipcp)));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(ifp.gw == 0);
+    ASSERT(((struct ipcp *) ppp_payload(frame))->code ==
+           MG_PPP_IPCP_CFG_REJECT);
+    ASSERT(ifp.nsent == 3);
+  }
+}
+
+#if MG_ENABLE_IPV6
+static void test_ipv6cp(void) {
+  uint8_t frame[64];
+  struct mg_tcpip_if ifp;
+  struct mg_str raw, pay;
+  enum mg_l2proto proto;
+
+  {  // IPv6CP request with interface ID is ACKed
+    uint8_t ipv6cp[] = {MG_PPP_IPV6CP_CFG_REQ, 1, 0, 14,
+                        MG_PPP_IPV6CP_OPT_IFCID, 10, 2, 3, 4, 5, 6, 7, 8, 9};
+    init_if(&ifp, MG_TCPIP_L2_PPP);
+    s_lcpup = true;
+    raw = mg_str_n((char *) frame,
+                   mk_ppp(frame, MG_PPP_PROTO_IPV6CP, ipv6cp,
+                          sizeof(ipv6cp)));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(memcmp(&((struct mg_l2addr *) ifp.gw6mac)->addr.ieee64, ipv6cp + 6,
+                  8) == 0);
+    ASSERT(((struct ipv6cp *) ppp_payload(frame))->code ==
+           MG_PPP_IPV6CP_CFG_ACK);
+    ASSERT(ifp.nsent == 2);
+  }
+  {  // IPv6CP request with zero interface ID is rejected
+    uint8_t ipv6cp[] = {MG_PPP_IPV6CP_CFG_REQ, 1, 0, 14,
+                        MG_PPP_IPV6CP_OPT_IFCID, 10, 0, 0, 0, 0, 0, 0, 0, 0};
+    init_if(&ifp, MG_TCPIP_L2_PPP);
+    s_lcpup = true;
+    raw = mg_str_n((char *) frame,
+                   mk_ppp(frame, MG_PPP_PROTO_IPV6CP, ipv6cp,
+                          sizeof(ipv6cp)));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(((struct ipv6cp *) ppp_payload(frame))->code ==
+           MG_PPP_IPV6CP_CFG_REJECT);
+    ASSERT(ifp.nsent == 1);
+  }
+}
+#endif
+
+static void test_ppp(void) {
+  uint8_t frame[96];
+  struct mg_tcpip_if ifp;
+  struct mg_str raw, pay;
+  enum mg_l2proto proto;
+
+  {  // IPv4 packet is accepted after LCP is up
+    uint8_t payload[sizeof(struct ip)];
+    memset(payload, 0, sizeof(payload));
+    init_if(&ifp, MG_TCPIP_L2_PPP);
+    MG_DEBUG(("MTU: %u, frame size: %u", ifp.l2mtu, ifp.framesize));
+    ASSERT(ifp.l2mtu != 0);
+    ASSERT(ifp.framesize != 0);
+    s_lcpup = true;
+    raw = mg_str_n((char *) frame,
+                   mk_ppp(frame, MG_PPP_PROTO_IP, payload, sizeof(payload)));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == true);
+    ASSERT(proto == MG_TCPIP_L2PROTO_IPV4);
+    ASSERT(pay.len == sizeof(payload));
+    ASSERT(memcmp(pay.buf, payload, sizeof(payload)) == 0);
+  }
+  {  // IPv4 packet is discarded while LCP is down
+    uint8_t payload[sizeof(struct ip)];
+    memset(payload, 0, sizeof(payload));
+    init_if(&ifp, MG_TCPIP_L2_PPP);
+    s_lcpup = false;
+    raw = mg_str_n((char *) frame,
+                   mk_ppp(frame, MG_PPP_PROTO_IP, payload, sizeof(payload)));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+  }
+#if MG_ENABLE_IPV6
+  {  // IPv6 packet is accepted after LCP is up
+    uint8_t payload[sizeof(struct ip6)];
+    memset(payload, 0, sizeof(payload));
+    init_if(&ifp, MG_TCPIP_L2_PPP);
+    s_lcpup = true;
+    raw = mg_str_n((char *) frame,
+                   mk_ppp(frame, MG_PPP_PROTO_IPV6, payload,
+                          sizeof(payload)));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == true);
+    ASSERT(proto == MG_TCPIP_L2PROTO_IPV6);
+    ASSERT(pay.len == sizeof(payload));
+    ASSERT(memcmp(pay.buf, payload, sizeof(payload)) == 0);
+  }
+  {  // IPv6 packet is discarded while LCP is down
+    uint8_t payload[sizeof(struct ip6)];
+    memset(payload, 0, sizeof(payload));
+    init_if(&ifp, MG_TCPIP_L2_PPP);
+    s_lcpup = false;
+    raw = mg_str_n((char *) frame,
+                   mk_ppp(frame, MG_PPP_PROTO_IPV6, payload,
+                          sizeof(payload)));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+  }
+#endif
+  {  // Unknown protocol is rejected after LCP is up
+    uint8_t payload[] = {1, 2, 3, 4};
+    init_if(&ifp, MG_TCPIP_L2_PPP);
+    s_lcpup = true;
+    raw = mg_str_n((char *) frame,
+                   mk_ppp(frame, 0x1234, payload, sizeof(payload)));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(ifp.nsent == 1);
+  }
+  {  // Unknown protocol is discarded while LCP is down
+    uint8_t payload[] = {1, 2, 3, 4};
+    init_if(&ifp, MG_TCPIP_L2_PPP);
+    s_lcpup = false;
+    raw = mg_str_n((char *) frame,
+                   mk_ppp(frame, 0x1234, payload, sizeof(payload)));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(ifp.nsent == 0);
+  }
+}
+
+static void test_pppoe(void) {
+  uint8_t frame[96];
+  struct mg_tcpip_if ifp;
+  struct mg_str raw, pay;
+  enum mg_l2proto proto;
+
+  {  // PADO moves discovery to request state
+    init_if(&ifp, MG_TCPIP_L2_PPPoE);
+    MG_DEBUG(("MTU: %u, frame size: %u", ifp.l2mtu, ifp.framesize));
+    ASSERT(ifp.l2mtu != 0);
+    ASSERT(ifp.framesize != 0);
+    s_state = MG_PPPoE_ST_DISC;
+    raw = mg_str_n((char *) frame,
+                   mk_pppoe_disc(frame, MG_PPPoE_PADO, 0, NULL, 0));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(s_state == MG_PPPoE_ST_REQ);
+    ASSERT(ifp.nsent == 1);
+  }
+  {  // PADO is ignored outside discovery state
+    init_if(&ifp, MG_TCPIP_L2_PPPoE);
+    s_state = MG_PPPoE_ST_REQ;
+    raw = mg_str_n((char *) frame,
+                   mk_pppoe_disc(frame, MG_PPPoE_PADO, 0, NULL, 0));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(s_state == MG_PPPoE_ST_REQ);
+    ASSERT(ifp.nsent == 0);
+  }
+  {  // PADS establishes the session
+    init_if(&ifp, MG_TCPIP_L2_PPPoE);
+    s_state = MG_PPPoE_ST_REQ;
+    raw = mg_str_n((char *) frame,
+                   mk_pppoe_disc(frame, MG_PPPoE_PADS, 0x1234, NULL, 0));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(s_state == MG_PPPoE_ST_SESS);
+    ASSERT(s_id == mg_htons(0x1234));
+  }
+  {  // PADS is ignored outside request state
+    init_if(&ifp, MG_TCPIP_L2_PPPoE);
+    s_state = MG_PPPoE_ST_DISC;
+    raw = mg_str_n((char *) frame,
+                   mk_pppoe_disc(frame, MG_PPPoE_PADS, 0x1234, NULL, 0));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(s_state == MG_PPPoE_ST_DISC);
+  }
+  {  // PADT matching the session tears it down
+    init_if(&ifp, MG_TCPIP_L2_PPPoE);
+    s_state = MG_PPPoE_ST_SESS;
+    s_id = mg_htons(0x1234);
+    s_lcpup = true;
+    raw = mg_str_n((char *) frame,
+                   mk_pppoe_disc(frame, MG_PPPoE_PADT, 0x1234, NULL, 0));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(s_state == MG_PPPoE_ST_DISC);
+    ASSERT(s_id == 0);
+    ASSERT(s_lcpup == false);
+  }
+  {  // PADT for a different session is ignored
+    init_if(&ifp, MG_TCPIP_L2_PPPoE);
+    s_state = MG_PPPoE_ST_SESS;
+    s_id = mg_htons(0x4321);
+    s_lcpup = true;
+    raw = mg_str_n((char *) frame,
+                   mk_pppoe_disc(frame, MG_PPPoE_PADT, 0x1234, NULL, 0));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+    ASSERT(s_state == MG_PPPoE_ST_SESS);
+    ASSERT(s_id == mg_htons(0x4321));
+    ASSERT(s_lcpup == true);
+  }
+  {  // PPPoE session packet is accepted in session state
+    uint8_t payload[sizeof(struct ip)];
+    memset(payload, 0, sizeof(payload));
+    init_if(&ifp, MG_TCPIP_L2_PPPoE);
+    s_state = MG_PPPoE_ST_SESS;
+    s_lcpup = true;
+    raw = mg_str_n((char *) frame,
+                   mk_pppoe_sess(frame, 0x1234, MG_PPP_PROTO_IP, payload,
+                                 sizeof(payload)));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == true);
+    ASSERT(proto == MG_TCPIP_L2PROTO_IPV4);
+    ASSERT(pay.len == sizeof(payload));
+    ASSERT(memcmp(pay.buf, payload, sizeof(payload)) == 0);
+  }
+  {  // PPPoE session packet is discarded outside session state
+    uint8_t payload[sizeof(struct ip)];
+    memset(payload, 0, sizeof(payload));
+    init_if(&ifp, MG_TCPIP_L2_PPPoE);
+    s_state = MG_PPPoE_ST_REQ;
+    s_lcpup = true;
+    raw = mg_str_n((char *) frame,
+                   mk_pppoe_sess(frame, 0x1234, MG_PPP_PROTO_IP, payload,
+                                 sizeof(payload)));
+    proto = MG_TCPIP_L2PROTO_ARP;
+    ASSERT(mg_l2_rx(&ifp, &proto, &pay, &raw) == false);
+  }
+}
+
+#define DASHBOARD(x) \
+  printf("HEALTH_DASHBOARD\t\"%s\": %s,\n", x, s_error ? "false" : "true")
+
+int main(void) {
+  s_error = false;
+  test_fcs();
+  DASHBOARD("fcs");
+
+  s_error = false;
+  test_lcp();
+  DASHBOARD("lcp");
+
+  s_error = false;
+  test_ipcp();
+  DASHBOARD("ipcp");
+
+#if MG_ENABLE_IPV6
+  s_error = false;
+  test_ipv6cp();
+  DASHBOARD("ipv6cp");
+#endif
+
+  s_error = false;
+  test_ppp();
+  DASHBOARD("ppp");
+
+  s_error = false;
+  test_pppoe();
+  printf("HEALTH_DASHBOARD\t\"pppoe\": %s\n", s_error ? "false" : "true");
+
+#ifdef NO_ABORT
+  if (s_abort != 0) return EXIT_FAILURE;
+#endif
+
+  printf("SUCCESS. Total tests: %d\n", s_num_tests);
+  return EXIT_SUCCESS;
+}

test/pppoe-server-options

@@ -0,0 +1,7 @@
+# PPP options for the PPPoE server
+noauth
+10.0.0.1:10.67.15.1
+lcp-echo-interval 1
+lcp-echo-failure 2
++ipv6
+ipv6cp-use-ipaddr

test/pppoe_tap_test.c

@@ -0,0 +1,142 @@
+#define MG_ENABLE_TCPIP 1
+#define MG_ENABLE_TCPIP_DRIVER_INIT 0
+
+#include <sys/socket.h>
+#ifndef __OpenBSD__
+#include <linux/if.h>
+#include <linux/if_tun.h>
+#else
+#include <net/if.h>
+#include <net/if_tun.h>
+#include <net/if_types.h>
+#endif
+#include <sys/ioctl.h>
+
+#include "mongoose.c"
+
+#define WAIT_MS 5000
+
+static size_t tap_rx(void *buf, size_t len, struct mg_tcpip_if *ifp) {
+  ssize_t received = read(*(int *) ifp->driver_data, buf, len);
+  usleep(1);
+  if (received < 0) return 0;
+  return (size_t) received;
+}
+
+static size_t tap_tx(const void *buf, size_t len, struct mg_tcpip_if *ifp) {
+  ssize_t res = write(*(int *) ifp->driver_data, buf, len);
+  if (res < 0) {
+    MG_ERROR(("tap_tx failed: %d", errno));
+    return 0;
+  }
+  return (size_t) res;
+}
+
+static bool tap_poll(struct mg_tcpip_if *ifp, bool s1) {
+  return s1 && ifp->driver_data ? true : false;
+}
+
+int main(int argc, char *argv[]) {
+  int res = EXIT_SUCCESS;
+  const char *iface = "tap0";
+  const char *mac = "02:00:01:02:03:78";
+#ifndef __OpenBSD__
+  const char *tuntap_device = "/dev/net/tun";
+#else
+  const char *tuntap_device = "/dev/tap0";
+#endif
+  uint16_t vlan_id = 3;
+  int fd, i;
+  struct ifreq ifr;
+  struct mg_mgr mgr;
+  struct mg_tcpip_driver driver;
+  struct mg_tcpip_if mif;
+
+  for (i = 1; i < argc; i++) {
+    if (strcmp(argv[i], "-i") == 0 && i + 1 < argc) {
+      iface = argv[++i];
+    } else if (strcmp(argv[i], "-mac") == 0 && i + 1 < argc) {
+      mac = argv[++i];
+    } else if (strcmp(argv[i], "-v") == 0 && i + 1 < argc) {
+      mg_log_set(atoi(argv[++i]));
+    } else if (strcmp(argv[i], "-vlan") == 0 && i + 1 < argc) {
+      vlan_id = (uint16_t) atoi(argv[++i]);
+    } else {
+      MG_ERROR(("unknown option %s", argv[i]));
+      return EXIT_FAILURE;
+    }
+  }
+
+  fd = open(tuntap_device, O_RDWR);
+  if (fd < 0) {
+    MG_ERROR(("Failed to open TAP device: %d", errno));
+    return EXIT_FAILURE;
+  }
+
+  memset(&ifr, 0, sizeof(ifr));
+  strncpy(ifr.ifr_name, iface, IFNAMSIZ);
+#ifndef __OpenBSD__
+  ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
+  if (ioctl(fd, TUNSETIFF, (void *) &ifr) < 0) {
+    MG_ERROR(("Failed to setup TAP interface: %s", ifr.ifr_name));
+    close(fd);
+    return EXIT_FAILURE;
+  }
+#else
+  ifr.ifr_flags = (short) (IFF_UP | IFF_BROADCAST | IFF_MULTICAST);
+  if (ioctl(fd, TUNSIFMODE, (void *) &ifr) < 0) {
+    MG_ERROR(("Failed to setup TAP interface: %s", ifr.ifr_name));
+    close(fd);
+    return EXIT_FAILURE;
+  }
+#endif
+  fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) | O_NONBLOCK);
+
+  memset(&driver, 0, sizeof(driver));
+  driver.tx = tap_tx;
+  driver.rx = tap_rx;
+  driver.poll = tap_poll;
+
+  memset(&mif, 0, sizeof(mif));
+  mif.driver = &driver;
+  mif.driver_data = &fd;
+#if MG_ENABLE_IPV6
+  mif.ip6[0] = mg_htonll(0x100000000000000);
+  mif.prefix[0] = 1;
+  mif.prefix_len = 64;
+  mif.gw6[0] = mg_htonll(0x100000000000000);
+  mif.gw6_ready = true;
+#endif
+  mif.l2type = MG_TCPIP_L2_PPPoE;
+  mif.l2data.eth.vlan_id = vlan_id;
+  sscanf(mac, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", &mif.mac[0], &mif.mac[1],
+         &mif.mac[2], &mif.mac[3], &mif.mac[4], &mif.mac[5]);
+
+  mg_mgr_init(&mgr);
+  mg_tcpip_init(&mgr, &mif);
+  MG_INFO(("Opened TAP interface %s, VLAN %u", iface, vlan_id));
+
+  for (i = 0; i < WAIT_MS / 10 && (mif.state != MG_TCPIP_STATE_READY
+#if MG_ENABLE_IPV6
+                                   || mif.state6 != MG_TCPIP_STATE_READY
+#endif
+                                  ); i++) {
+    mg_mgr_poll(&mgr, 10);
+    usleep(10000);
+  }
+
+  if (mif.state != MG_TCPIP_STATE_READY) {
+    MG_ERROR(("IP FAILED %u", mif.state));
+    res = EXIT_FAILURE;
+  }
+#if MG_ENABLE_IPV6
+  if (mif.state6 != MG_TCPIP_STATE_READY) {
+    MG_ERROR(("IPv6 FAILED %u", mif.state6));
+    res = EXIT_FAILURE;
+  }
+#endif
+
+  mg_mgr_free(&mgr);
+  close(fd);
+  return res;
+}

test/setup_ga_network.sh

@@ -23,18 +23,20 @@ echo
 
 # Package installation
 echo "Package installation"
-sudo apt-get -y install isc-dhcp-server net-tools radvd
-sudo systemctl stop radvd # just in case they think it is cool to start it
+sudo apt-get -y install isc-dhcp-server net-tools radvd ppp pppoe
+sudo systemctl stop radvd # they think it is cool to start it
 # sudo apt-get -y install build-essential sshpass
 echo
 
 echo "Network configuration script: Bridge"
 sudo ip link add $BRIDGE type bridge	# Create brige
-sudo ifconfig $BRIDGE $BRIDGE_IP netmask $BRIDGE_MASK up
-sudo ifconfig $BRIDGE:1 $GATEWAY_IP netmask $BRIDGE_MASK up
-sudo ifconfig $BRIDGE:2 $HOST_IP netmask $BRIDGE_MASK up
-sudo ip -6 addr add $BRIDGE_IPV6/64 dev $BRIDGE
-sudo ip -6 addr add $HOST_IPV6/64 dev $BRIDGE:1
+sudo ifconfig $BRIDGE $BRIDGE_IP netmask $BRIDGE_MASK up	# its IP
+sudo ifconfig $BRIDGE:1 $GATEWAY_IP netmask $BRIDGE_MASK up	# IP announced by DHCP as gateway
+sudo ifconfig $BRIDGE:2 $HOST_IP netmask $BRIDGE_MASK up	# IP exported for LAN (dut) connections
+sudo ip -6 addr add $BRIDGE_IPV6/64 dev $BRIDGE			# its IPv6
+sudo ip -6 addr add $HOST_IPV6/64 dev $BRIDGE:1			# IPv6 exported for LAN (dut) connections
+sudo ip link add link $BRIDGE name $BRIDGE.3 type vlan id 3	# Create VLAN for PPPoE+VLAN tests
+sudo ifconfig $BRIDGE.3 up
 echo
 
 echo "Network configuration script: TAP"
@@ -73,10 +75,20 @@ sudo cp test/dhcpd.conf /etc/dhcp/dhcpd.conf
 sudo chmod a+w /var/lib/dhcp/*
 sudo dhcpd mg_bridge0 &
 echo
+
+# Setup Router Advertising server
 echo "radvd listening at $BRIDGE_IPV6"
 sudo ip link set $BRIDGE up # there's no physical port, so we need to set link up for radvd to work
 sudo radvd -n -d 5 -C test/radvd.conf &
 echo
+
+# Setup PPPoE server
+echo "pppoe-server listening at $BRIDGE.3"
+printf "lock\n" | sudo tee /etc/ppp/options
+sudo pppoe-server -F -D -O test/pppoe-server-options -I $BRIDGE.3 &
+echo
+
+# Export generic server addresses so DUTs can connect to them
 echo "Host listening at $HOST_IP and $HOST_IPV6"
 export HOST_IP
 export HOST_IPV6
@@ -88,8 +100,8 @@ wget https://cesanta.com/robots.txt
 echo robots.txt:
 cat  robots.txt
 rm   robots.txt
-wget https://ipv6.google.com/
-rm index.html
+wget https://ipv6.google.com/ || true
+rm index.html || true
 echo
 
 # Confirm OK

test/unit_test.c

@@ -301,6 +301,13 @@ static void test_base64(void) {
   ASSERT(mg_base64_decode("AAA=", 4, buf, 2) == 0);
   ASSERT(mg_base64_decode("AAA=", 4, buf, 3) == 0);
   ASSERT(mg_base64_decode("AAA=", 4, buf, 4) == 2);
+
+  ASSERT(mg_base64url_encode((uint8_t *) "???", 3, buf, sizeof(buf)) == 4);
+  ASSERT(strcmp(buf, "Pz8_") == 0);
+  ASSERT(mg_base64url_decode("Pz8_", 4, buf, sizeof(buf)) == 3);
+  ASSERT(strcmp(buf, "???") == 0);
+  ASSERT(mg_base64url_decode("Pz8/", 4, buf, sizeof(buf)) == 0);
+  ASSERT(mg_base64url_decode("A", 1, buf, sizeof(buf)) == 0);
 }
 
 static void test_iobuf(void) {
@@ -339,7 +346,7 @@ static void sntp_cb(struct mg_connection *c, int ev, void *ev_data) {
     int64_t received = *(int64_t *) ev_data;
     *(int64_t *) c->fn_data = received;
     MG_DEBUG(("got time: %lld", received));
-#if MG_ARCH == MG_ARCH_UNIX
+#if MG_ARCH == MG_ARCH_UNIX && defined(__STDC__) && defined(__STDC_VERSION__)
     struct timeval tv = {0, 0};
     gettimeofday(&tv, 0);
     int64_t ms = (int64_t) tv.tv_sec * 1000 + tv.tv_usec / 1000;
@@ -1462,7 +1469,7 @@ static void test_tls(void) {
   const char *url = "https://localhost:12347";
   char buf[FETCH_BUF_SIZE];
   struct mg_tls_opts opts;
-  struct mg_str data = mg_unpacked("/Makefile");
+  struct mg_str data = mg_unpacked("/fuzz.c");
   char bigdata[FETCH_BUF_SIZE - 256];  // leave extra room
   struct mg_str bd;
   ASSERT(data.buf != NULL && data.len > 0);
@@ -1505,6 +1512,7 @@ static void test_tls(void) {
     // otherwise it will end with 200 and shorter file contents
     ASSERT(fetch(&mgr, buf, "https://localhost:8443",
                  "GET /thefile HTTP/1.0\n\n") == 200);
+    data = mg_unpacked("/Makefile");
     ASSERT(cmpbody(buf, data.buf) == 0);  // "thefile" links to Makefile
     ASSERT(system("killall tls_multirec/server") == 0);
   } else {
@@ -1612,9 +1620,8 @@ static void test_http_client(void) {
   opts.name = mg_url_host(url);
 
   // Test empty CA
-  // Disable mbedTLS: https://github.com/Mbed-TLS/mbedtls/issues/7075
-#if MG_TLS != MG_TLS_MBED
   opts.ca = mg_str("");
+  opts.name = mg_url_host(url);
   c = mg_http_connect(&mgr, url, f3, &ok);
   mg_tls_init(c, &opts);
   ok = 0;
@@ -1622,7 +1629,21 @@ static void test_http_client(void) {
   MG_INFO(("OK: %d", ok));
   ASSERT(ok == 200);
   mg_mgr_poll(&mgr, 1);
+  // Make host validation fail
+  c = mg_http_connect(&mgr, url, f3, &ok);
+  ASSERT(c != NULL);
+  opts.name = mg_str("dummy");  // Set some invalid hostname value
+  mg_tls_init(c, &opts);
+  ok = 0;
+  for (i = 0; i < 500 && ok <= 0; i++) mg_mgr_poll(&mgr, 10);
+  MG_INFO(("OK: %d", ok));
+#if MG_TLS != MG_TLS_MBED || !defined(MBEDTLS_VERSION_NUMBER) || \
+    MBEDTLS_VERSION_NUMBER < 0x03030000 ||                       \
+    MBEDTLS_VERSION_NUMBER >= 0x04000000
+  // Ignore result for 3.3.0 <= mbedTLS < 4.0.0 : https://github.com/Mbed-TLS/mbedtls/issues/7075
+  ASSERT(ok == 777);
 #endif
+  mg_mgr_poll(&mgr, 1);
 #endif
 
 #if MG_ENABLE_IPV6
@@ -2308,6 +2329,19 @@ static void test_str(void) {
     ASSERT(chkdbl(mg_str("123e-3"), 0.123));
   }
 
+#if defined(NO_ZU_TEST) || (defined(_MSC_VER) && _MSC_VER < 1700)
+  // VC98 does not have '%zu', some old compilers may also not support it
+#else
+  ASSERT(sn("%zu", 0));
+  ASSERT(sn("%zu", -1));
+  ASSERT(sn("%zu", -2));
+  ASSERT(sn("%zd", 123));
+#if !defined(_MSC_VER)
+  ASSERT(sn("%zd", -3));  // MSVC casts to unsigned
+#endif
+  ASSERT(sn("%zu", 0x1234));
+#endif
+
   ASSERT(sn("%d", 0));
   ASSERT(sn("%d", 1));
   ASSERT(sn("%d", -1));
@@ -2759,6 +2793,11 @@ static void test_util(void) {
          ((uint8_t *) &ipv4)[2] == 0x45);
   ASSERT(MG_LOAD_BE24(&ipv4) == 0xef2345);
 
+  ASSERT(mg_timegm(2023, 1, 1, 0, 0, 0) == 1672531200);
+  ASSERT(mg_timegm(2025, 12, 31, 23, 59, 59) == 1767225599);
+  ASSERT(mg_timegm(2024, 2, 1, 0, 0, 0) == 1706745600);
+  ASSERT(mg_timegm(2000, 4, 1, 0, 0, 0) == 954547200);
+
   memcpy(&ipv3, d64, sizeof(ipv3));
 #if defined(_MSC_VER) && _MSC_VER < 1700
   // VC98 doesn't suppport LL suffix
@@ -2816,6 +2855,13 @@ static void test_util(void) {
   e = "\x20\x01\x48\x60\x48\x60\x00\x00\x00\x00\x00\x00\x00\x00\x88\x88";
   ASSERT(memcmp(&a.addr.ip6, e, sizeof(a.addr.ip6)) == 0);
 
+  ASSERT(mg_aton(mg_str("12345::1"), &a) == false);
+  ASSERT(mg_aton(mg_str("1:::2"), &a) == false);
+  ASSERT(mg_aton(mg_str("1::2::3"), &a) == false);
+  ASSERT(mg_aton(mg_str("1:2:3:4:5:6:7"), &a) == false);
+  ASSERT(mg_aton(mg_str("1:2:3:4:5:6:7:8:9"), &a) == false);
+  ASSERT(mg_aton(mg_str("1:2:3:4:5:6:7:g"), &a) == false);
+
   ASSERT(mg_url_decode("a=%", 3, buf, sizeof(buf), 0) < 0);
   ASSERT(mg_url_decode("&&&a=%", 6, buf, sizeof(buf), 0) < 0);
   ASSERT(mg_url_decode("a=%1", 4, buf, sizeof(buf), 0) < 0);
@@ -2988,11 +3034,18 @@ static void test_util(void) {
 static void test_crc32(void) {
   //  echo -n aaa | cksum -o3
   ASSERT(mg_crc32(0, 0, 0) == 0);
-  ASSERT(mg_crc32(0, "a", 1) == 3904355907);
+  ASSERT(mg_crc32(0, "a", 1) == 3904355907U);
   ASSERT(mg_crc32(0, "abc", 3) == 891568578);
   ASSERT(mg_crc32(mg_crc32(0, "ab", 2), "c", 1) == 891568578);
 }
 
+static void test_crc16(void) {
+  ASSERT(mg_crc16(0, 0, 0) == 0);
+  ASSERT(mg_crc16(0, "a", 1) == 0x82f7);
+  ASSERT(mg_crc16(0, "abc", 3) == 0x9e25);
+  ASSERT(mg_crc16(mg_crc16(0, "ab", 2), "c", 1) == 0x9e25);
+}
+
 static void us(struct mg_connection *c, int ev, void *ev_data) {
   struct mg_http_message *hm = (struct mg_http_message *) ev_data;
   if (ev == MG_EV_HTTP_MSG && mg_match(hm->uri, mg_str("/upload"), NULL)) {
@@ -3160,7 +3213,7 @@ static void test_http_chunked_case(mg_event_handler_t s, mg_event_handler_t c,
   struct mg_mgr mgr;
   uint32_t i, crc = 0, expected_crc = mg_crc32(0, expected, strlen(expected));
   struct mg_connection *conn;
-  static uint16_t port = 32344;  // To prevent bind errors on Windows
+  static uint16_t port = 32344;  // To prevent bind errors on Windows 
   mg_snprintf(url, sizeof(url), "http://127.0.0.1:%d", port++);
   mg_mgr_init(&mgr);
   mg_http_listen(&mgr, url, s, NULL);
@@ -3714,13 +3767,23 @@ static void test_json(void) {
     ASSERT(b == true);
     ASSERT(mg_json_get(json, "$.b[2]", &len) < 0);
 
-    json = mg_str("[\"YWJj\", \"0100026869\"]");
+    json = mg_str("[\"YWJj\", \"0100026869\", \"\", \"abc\", \"0g\"]");
     ASSERT((str = mg_json_get_b64(json, "$[0]", &len)) != NULL);
     ASSERT(len == 3 && memcmp(str, "abc", (size_t) len) == 0);
     mg_free(str);
     ASSERT((str = mg_json_get_hex(json, "$[1]", &len)) != NULL);
     ASSERT(len == 5 && memcmp(str, "\x01\x00\x02hi", (size_t) len) == 0);
     mg_free(str);
+    ASSERT((str = mg_json_get_hex(json, "$[2]", &len)) != NULL);
+    ASSERT(len == 0 && str[0] == '\0');
+    mg_free(str);
+    len = 42;
+    str = mg_json_get_hex(json, "$[3]", &len);
+    ASSERT(str == NULL && len == 42);
+    mg_free(str);
+    str = mg_json_get_hex(json, "$[4]", &len);
+    ASSERT(str == NULL && len == 42);
+    mg_free(str);
 
     json = mg_str("{\"a\":[1,2,3], \"ab\": 2}");
     ASSERT(mg_json_get_long(json, "$.a[0]", -42) == 1);
@@ -3930,8 +3993,7 @@ static void test_poll(void) {
   int count = 0, i;
   struct mg_mgr mgr;
   mg_mgr_init(&mgr);
-  mg_http_listen(&mgr, "http://127.0.0.1:42346", ph,
-                 &count);  // To prevent bind errors on Windows
+  mg_http_listen(&mgr, "http://127.0.0.1:12340", ph, &count);
   for (i = 0; i < 10; i++) mg_mgr_poll(&mgr, 0);
   ASSERT(count == 10);
   mg_mgr_free(&mgr);
@@ -4298,6 +4360,128 @@ static void test_rsa(void) {
     ASSERT(!mg_rsa_verify(em, 256, tv_mhash));
     em[50] = tv_em[50];
   }
+  {
+    static const uint8_t sha256_di[] = {
+        0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01,
+        0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04, 0x20};
+    static const uint8_t sha384_di[] = {
+        0x30, 0x41, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01,
+        0x65, 0x03, 0x04, 0x02, 0x02, 0x05, 0x00, 0x04, 0x30};
+    uint8_t hash[48], em[256];
+    size_t i, pslen;
+
+    for (i = 0; i < sizeof(hash); i++) hash[i] = (uint8_t) i;
+
+    memset(em, 0xff, sizeof(em));
+    em[0] = 0, em[1] = 1;
+    pslen = sizeof(em) - 3 - sizeof(sha256_di) - 32;
+    em[2 + pslen] = 0;
+    memcpy(em + 3 + pslen, sha256_di, sizeof(sha256_di));
+    memcpy(em + 3 + pslen + sizeof(sha256_di), hash, 32);
+    ASSERT(mg_rsa_pkcs_verify(em, sizeof(em), hash, 32));
+
+    em[1] = 2;  // bad block type
+    ASSERT(!mg_rsa_pkcs_verify(em, sizeof(em), hash, 32));
+    em[1] = 1;
+    em[10] = 0;  // bad padding
+    ASSERT(!mg_rsa_pkcs_verify(em, sizeof(em), hash, 32));
+    em[10] = 0xff;
+    em[3 + pslen + 15] ^= 1;  // bad DigestInfo
+    ASSERT(!mg_rsa_pkcs_verify(em, sizeof(em), hash, 32));
+    em[3 + pslen + 15] ^= 1;
+    em[sizeof(em) - 1] ^= 1;  // bad hash
+    ASSERT(!mg_rsa_pkcs_verify(em, sizeof(em), hash, 32));
+
+    memset(em, 0, sizeof(em));  // former suffix-only bypass
+    memcpy(em + sizeof(em) - 32, hash, 32);
+    ASSERT(!mg_rsa_pkcs_verify(em, sizeof(em), hash, 32));
+
+    memset(em, 0xff, sizeof(em));
+    em[0] = 0, em[1] = 1;
+    pslen = sizeof(em) - 3 - sizeof(sha384_di) - 48;
+    em[2 + pslen] = 0;
+    memcpy(em + 3 + pslen, sha384_di, sizeof(sha384_di));
+    memcpy(em + 3 + pslen + sizeof(sha384_di), hash, 48);
+    ASSERT(mg_rsa_pkcs_verify(em, sizeof(em), hash, 48));
+    ASSERT(!mg_rsa_pkcs_verify(em, sizeof(em), hash, 20));
+  }
+#endif
+}
+
+static void test_jwt(void) {
+  char jwt[512], claims[128], got[128], hdr[128], extra[64], tampered[512];
+  struct mg_jwt_opts opts, bad;
+  const char *dot;
+  char *str;
+  size_t n, m;
+
+  mg_snprintf(claims, sizeof(claims), "{%m:%m,%m:%d}", MG_ESC("sub"),
+              MG_ESC("admin"), MG_ESC("iat"), 123);
+  mg_snprintf(extra, sizeof(extra), "%m:%m", MG_ESC("cty"), MG_ESC("JWT"));
+  memset(&opts, 0, sizeof(opts));
+  opts.claims = mg_str(claims);
+  opts.header = mg_str(extra);
+  opts.kid = mg_str("hmac-key-1");
+  opts.secret = mg_str("secret");
+  n = mg_jwt_sign_hs256(&opts, jwt, sizeof(jwt));
+  ASSERT(n > 0 && n + 1 < sizeof(jwt));
+  jwt[n] = '\0';
+
+  dot = strchr(jwt, '.');
+  ASSERT(dot != NULL);
+  ASSERT(mg_base64url_decode(jwt, (size_t) (dot - jwt), hdr,
+                             sizeof(hdr)) > 0);
+  str = mg_json_get_str(mg_str(hdr), "$.kid");
+  ASSERT(str != NULL && strcmp(str, "hmac-key-1") == 0);
+  mg_free(str);
+  str = mg_json_get_str(mg_str(hdr), "$.cty");
+  ASSERT(str != NULL && strcmp(str, "JWT") == 0);
+  mg_free(str);
+
+  m = mg_jwt_verify_hs256(mg_str_n(jwt, n), &opts, got, sizeof(got));
+  ASSERT(m == strlen(claims));
+  ASSERT(strcmp(got, claims) == 0);
+  bad = opts;
+  bad.secret = mg_str("bad-secret");
+  ASSERT(mg_jwt_verify_hs256(mg_str_n(jwt, n), &bad, got,
+                             sizeof(got)) == 0);
+  memcpy(tampered, jwt, n + 1);
+  tampered[n - 1] = tampered[n - 1] == 'A' ? 'B' : 'A';
+  ASSERT(mg_jwt_verify_hs256(mg_str_n(tampered, n), &opts, got,
+                             sizeof(got)) == 0);
+  ASSERT(mg_jwt_sign_hs256(&opts, got, 10) == 0);
+  ASSERT(mg_jwt_verify_hs256(mg_str_n(jwt, n), &opts, got, 4) == 0);
+
+#if MG_TLS == MG_TLS_BUILTIN
+  {
+    const char *key_pem =
+        "-----BEGIN EC PRIVATE KEY-----\n"
+        "MHcCAQEEIAVdo8UAScxG7jiuNY2UZESNX/KPH8qJ0u0gOMMsAzYWoAoGCCqGSM49\n"
+        "AwEHoUQDQgAEqN6BIhvgbk7ecmUcn8Da9Avkj/uDNERtqWJG9r/or26X4u9jR5Jl\n"
+        "4hf5Gx17YJkq5/z3k6ogPDPpoAYWIw1/sw==\n"
+        "-----END EC PRIVATE KEY-----\n";
+    uint8_t key[32], pub[64];
+
+    memset(&opts, 0, sizeof(opts));
+    opts.claims = mg_str(claims);
+    opts.kid = mg_str("ec-key-1");
+    opts.private_key = key;
+    opts.public_key = pub;
+    ASSERT(mg_uecc_parse_private_key(mg_str(key_pem), key, sizeof(key)) == 32);
+    ASSERT(mg_uecc_compute_public_key(key, pub, mg_uecc_secp256r1()) == 1);
+    n = mg_jwt_sign_es256(&opts, jwt, sizeof(jwt));
+    ASSERT(n > 0 && n + 1 < sizeof(jwt));
+    jwt[n] = '\0';
+    m = mg_jwt_verify_es256(mg_str_n(jwt, n), &opts, got, sizeof(got));
+    ASSERT(m == strlen(claims));
+    ASSERT(strcmp(got, claims) == 0);
+    ASSERT(mg_jwt_verify_hs256(mg_str_n(jwt, n), &bad, got,
+                               sizeof(got)) == 0);
+    memcpy(tampered, jwt, n + 1);
+    tampered[n - 1] = tampered[n - 1] == 'A' ? 'B' : 'A';
+    ASSERT(mg_jwt_verify_es256(mg_str_n(tampered, n), &opts, got,
+                               sizeof(got)) == 0);
+  }
 #endif
 }
 
@@ -4308,6 +4492,7 @@ static void test_crypto(void) {
   test_sha384();
   test_x25519();
   test_rsa();
+  test_jwt();
 }
 
 static void dash_custom(struct mg_connection *c, int ev, void *ev_data) {
@@ -4422,15 +4607,15 @@ static bool set3_fn(enum mg_dash_op op, struct mg_dash_user *u) {
 static bool test_upload_dir(const struct mg_dash_user *u, char *buf, size_t len) {
   (void) u;
 #if MG_ARCH == MG_ARCH_UNIX || MG_ARCH == MG_ARCH_WIN32
-  mkdir("/tmp/mongoose_dash_test", 0755);
+  mkdir("mongoose_dash_test", 0755);
 #endif
-  mg_snprintf(buf, len, "%s", "/tmp/mongoose_dash_test");
+  mg_snprintf(buf, len, "%s", "mongoose_dash_test");
   return true;
 }
 
 struct test_file_entry {
   char name[64];
-  size_t size;
+  uint64_t size;
 };
 static struct test_file_entry s_test_file;
 static int s_test_file_index;
@@ -4588,7 +4773,7 @@ static void test_dash(void) {
 
   memset(&dash, 0, sizeof(dash));
   dash.session_auto_expiration_seconds = 1;
-  remove("/tmp/mongoose_dash_test/test.bin");
+  remove("mongoose_dash_test/test.bin");
 
   MG_DASH_ADD_FIELD_SET(&dash, &test_files_set);
   MG_DASH_ADD_FIELD_SET(&dash, &set1);
@@ -4917,6 +5102,11 @@ static void test_dash(void) {
     ASSERT(strstr(buf, test_bin_probe) != NULL);
     mg_mgr_free(&mgr3);
   }
+
+  remove("mongoose_dash_test/test.bin");
+#if MG_ARCH == MG_ARCH_UNIX || MG_ARCH == MG_ARCH_WIN32
+  rmdir("mongoose_dash_test");
+#endif
 }
 
 #define DASHBOARD(x) \
@@ -5288,8 +5478,8 @@ static void test_wakeup(void) {
   struct wudata *data;
   int i;
   mg_mgr_init(&mgr);        // Initialise event manager
-  mg_log_set(MG_LL_DEBUG);  // Set debug log level
-  c = mg_http_listen(&mgr, "http://127.0.0.1:42347", hwu, NULL);
+  mg_log_set(MG_LL_DEBUG);
+  c = mg_http_listen(&mgr, "http://127.0.0.1:12341", hwu, NULL);
   mg_wakeup_init(&mgr);  // Initialise wakeup socket pair
   data = (struct wudata *) calloc(1, sizeof(*data));  // wuthread owns it
   data->conn_id = c->id;
@@ -5328,6 +5518,7 @@ int main(void) {
   test_str();
   test_match();
   test_crc32();
+  test_crc16();
   DASHBOARD("misc");
 
   s_error = false;

tutorials/http/jwt-auth/Makefile

@@ -0,0 +1,26 @@
+PROG ?= example                   # Program we are building
+DELETE = rm -rf                   # Command to remove files
+OUT ?= -o $(PROG)                 # Compiler argument for output file
+SOURCES = main.c mongoose.c       # Source code files
+CFLAGS = -W -Wall -Wextra -g -I.  # Build options
+
+# Mongoose build options. See https://mongoose.ws/documentation/#build-options
+CFLAGS_MONGOOSE += -DMG_ENABLE_LINES=1
+CFLAGS_EXTRA ?= -DMG_TLS=MG_TLS_BUILTIN
+
+ifeq ($(OS),Windows_NT)   # Windows settings. Assume MinGW compiler. To use VC: make CC=cl CFLAGS=/MD OUT=/Feprog.exe
+  PROG ?= example.exe           # Use .exe suffix for the binary
+  CC = gcc                      # Use MinGW gcc compiler
+  CFLAGS += -lws2_32 -lbcrypt   # Link against Winsock library
+  DELETE = cmd /C del /Q /F /S  # Command prompt command to delete files
+  OUT ?= -o $(PROG)             # Build output
+endif
+
+all: $(PROG)              # Default target. Build and run program
+	$(RUN) ./$(PROG) $(ARGS)
+
+$(PROG): $(SOURCES)       # Build program from sources
+	$(CC) $(SOURCES) $(CFLAGS) $(CFLAGS_MONGOOSE) $(CFLAGS_EXTRA) $(OUT)
+
+clean:                    # Cleanup. Delete built program and all build artifacts
+	$(DELETE) $(PROG) *.o *.obj *.exe *.dSYM

tutorials/http/jwt-auth/README.md

@@ -0,0 +1,62 @@
+# JWT Bearer Authentication
+
+## Build and run:
+
+```sh
+make
+```
+
+## HS256:
+
+This path signs and verifies JWTs with the shared secret from `main.c`.
+
+```sh
+curl -i http://127.0.0.1:8000/login-hs256
+TOKEN=$(curl -s http://127.0.0.1:8000/login-hs256 | sed -n 's/.*"token":"\([^"]*\)".*/\1/p')
+curl -i -H "Authorization: Bearer $TOKEN" http://127.0.0.1:8000/
+```
+
+```txt
+HTTP/1.1 200 OK
+Content-Type: application/json
+Content-Length: 47         
+
+{"sub":"admin","scope":"dash:read dash:write"}
+```
+
+`scope` here is a JSON string value containing a space-delimited permission list; as an example.
+
+## ES256 (Requires MG_TLS_BUILTIN):
+
+This path parses the EC private key from `main.c`, signs the JWT with it, and
+derives the public key for verification to keep the example self-contained.
+
+```sh
+curl -i http://127.0.0.1:8000/login-es256
+TOKEN=$(curl -s http://127.0.0.1:8000/login-es256 | sed -n 's/.*"token":"\([^"]*\)".*/\1/p')
+curl -i -H "Authorization: Bearer $TOKEN" http://127.0.0.1:8000/
+```
+
+```txt
+HTTP/1.1 200 OK
+Content-Type: application/json
+Content-Length: 36         
+
+{"sub":"admin","scope":"dash:read"}
+```
+
+`scope` here is a JSON string value containing a space-delimited permission list; as an example.
+
+## Unauthorized access attempt example
+
+```sh
+curl -i -H "Authorization: Bearer bad.token.here" http://127.0.0.1:8000/
+```
+
+```txt
+HTTP/1.1 401 Unauthorized
+WWW-Authenticate: Bearer
+Content-Length: 13         
+
+Unauthorized
+```

tutorials/http/jwt-auth/main.c

@@ -0,0 +1,108 @@
+// Copyright (c) 2026 Cesanta Software Limited
+// All rights reserved
+//
+// HTTP server example. It issues and verifies JWT Bearer tokens.
+
+#include "mongoose.h"
+
+static const char *s_listen_on = "http://0.0.0.0:8000";
+static const char *s_secret = "change-me";
+enum { TOKEN_LEN = 1024, CLAIMS_LEN = 256, JWT_LEN = 1024 };
+static const char *s_ec_private_key =
+    "-----BEGIN EC PRIVATE KEY-----\n"
+    "MHcCAQEEIAVdo8UAScxG7jiuNY2UZESNX/KPH8qJ0u0gOMMsAzYWoAoGCCqGSM49\n"
+    "AwEHoUQDQgAEqN6BIhvgbk7ecmUcn8Da9Avkj/uDNERtqWJG9r/or26X4u9jR5Jl\n"
+    "4hf5Gx17YJkq5/z3k6ogPDPpoAYWIw1/sw==\n"
+    "-----END EC PRIVATE KEY-----\n";
+
+#if MG_TLS == MG_TLS_BUILTIN
+static size_t verify_es256(struct mg_str token, char *claims, size_t len) {
+  uint8_t key[32], pub[64];
+  struct mg_jwt_opts opts = {.public_key = pub};
+  // This keeps the example self-contained. A real verifier would usually keep
+  // only the issuer public key, selected by kid, not the signing private key.
+  if (mg_uecc_parse_private_key(mg_str(s_ec_private_key), key, sizeof(key)) !=
+          32 ||
+      mg_uecc_compute_public_key(key, pub, mg_uecc_secp256r1()) != 1) {
+    return 0;
+  }
+  return mg_jwt_verify_es256(token, &opts, claims, len);
+}
+#endif
+
+static void fn(struct mg_connection *c, int ev, void *ev_data) {
+  if (ev == MG_EV_HTTP_MSG) {
+    struct mg_http_message *hm = (struct mg_http_message *) ev_data;
+    char user[1], *token, *claims, *jwt;
+    token = (char *) mg_calloc(1, TOKEN_LEN);
+    claims = (char *) mg_calloc(1, CLAIMS_LEN);
+    jwt = (char *) mg_calloc(1, JWT_LEN);
+    if (token == NULL || claims == NULL || jwt == NULL) {
+      mg_http_reply(c, 500, "", "OOM\n");
+      mg_free(token);
+      mg_free(claims);
+      mg_free(jwt);
+      return;
+    }
+    mg_http_creds(hm, user, sizeof(user), token, TOKEN_LEN);
+
+    if (mg_match(hm->uri, mg_str("/login-hs256"), NULL)) {
+      struct mg_jwt_opts opts = {.kid = mg_str("hmac-key-1"),
+                                 .secret = mg_str(s_secret)};
+      size_t n;
+      mg_snprintf(claims, CLAIMS_LEN, "{%m:%m,%m:%m}", MG_ESC("sub"),
+                  MG_ESC("admin"), MG_ESC("scope"),
+                  MG_ESC("dash:read dash:write"));
+      opts.claims = mg_str(claims);
+      n = mg_jwt_sign_hs256(&opts, jwt, JWT_LEN);
+      mg_http_reply(c, n == 0 ? 500 : 200, "Content-Type: application/json\r\n",
+                    "{%m:%m}\n", MG_ESC("token"), MG_ESC(n == 0 ? "" : jwt));
+
+#if MG_TLS == MG_TLS_BUILTIN
+    } else if (mg_match(hm->uri, mg_str("/login-es256"), NULL)) {
+      uint8_t key[32];
+      struct mg_jwt_opts opts = {.kid = mg_str("ec-key-1"),
+                                 .private_key = key};
+      size_t keysz, n;
+      keysz =
+          mg_uecc_parse_private_key(mg_str(s_ec_private_key), key, sizeof(key));
+      // ES256 uses a raw 64-byte r || s signature. mg_jwt_sign_es256() signs it
+      // deterministically; applications can also hash the signing input and
+      // call mg_uecc_sign() directly if they need random-nonce ECDSA.
+      mg_snprintf(claims, CLAIMS_LEN, "{%m:%m,%m:%m}", MG_ESC("sub"),
+                  MG_ESC("admin"), MG_ESC("scope"), MG_ESC("dash:read"));
+      opts.claims = mg_str(claims);
+      n = keysz == 32 ? mg_jwt_sign_es256(&opts, jwt, JWT_LEN) : 0;
+      mg_http_reply(c, n == 0 ? 500 : 200, "Content-Type: application/json\r\n",
+                    "{%m:%m}\n", MG_ESC("token"), MG_ESC(n == 0 ? "" : jwt));
+#endif
+
+    } else {
+      struct mg_jwt_opts opts = {.secret = mg_str(s_secret)};
+      if (mg_jwt_verify_hs256(mg_str(token), &opts, claims, CLAIMS_LEN) > 0) {
+        mg_http_reply(c, 200, "Content-Type: application/json\r\n", "%s\n",
+                      claims);
+#if MG_TLS == MG_TLS_BUILTIN
+      } else if (verify_es256(mg_str(token), claims, CLAIMS_LEN) > 0) {
+        mg_http_reply(c, 200, "Content-Type: application/json\r\n", "%s\n",
+                      claims);
+#endif
+      } else {
+        mg_http_reply(c, 401, "WWW-Authenticate: Bearer\r\n", "Unauthorized\n");
+      }
+    }
+    mg_free(token);
+    mg_free(claims);
+    mg_free(jwt);
+  }
+}
+
+int main(void) {
+  struct mg_mgr mgr;
+  mg_log_set(MG_LL_DEBUG);
+  mg_mgr_init(&mgr);                            // Initialise event manager
+  mg_http_listen(&mgr, s_listen_on, fn, NULL);  // Create HTTP listener
+  for (;;) mg_mgr_poll(&mgr, 1000);             // Infinite event loop
+  mg_mgr_free(&mgr);
+  return 0;
+}

tutorials/http/jwt-auth/mongoose.c

@@ -0,0 +1 @@
+../../../mongoose.c

tutorials/http/jwt-auth/mongoose.h

@@ -0,0 +1 @@
+../../../mongoose.h

tutorials/mqtt/mqtt-client/arduino/nano-w5500-mqtt/w5500-mqtt.ino

@@ -12,7 +12,13 @@ struct mg_tcpip_spi spi = {
     NULL,  // SPI metadata
     [](void *) { digitalWrite(SS_PIN, LOW); SPI.beginTransaction(SPISettings()); },
     [](void *) { digitalWrite(SS_PIN, HIGH); SPI.endTransaction(); },
-    [](void *, uint8_t c) { return SPI.transfer(c); }, // Execute transaction
+    [](void *, uint8_t *w, uint8_t *r, size_t n) {  // Execute transaction
+        while (n--) {
+          uint8_t c = (w != NULL) ? *w++ : 0xFF;
+          uint8_t d = SPI.transfer(c);
+          if (r != NULL) *r++ = d;
+        }
+      },
 };
 struct mg_mgr mgr;                                     // Mongoose event manager
 struct mg_tcpip_if mif = {.mac = {2, 0, 1, 2, 3, 5}};  // Network interface

tutorials/nxp/frdm-rw612-xpresso-freertos-builtin-wifi/wifi/port/net/netif_mongoose.c

@@ -249,7 +249,7 @@ static struct mg_tcpip_if *s_ifp;
 static void deliver_packet_above(struct pb *buf, int ifc) {
   struct eth_hdr *ethhdr = (struct eth_hdr *) buf->data;
   w_pkt_d("Data RX: Driver=>Kernel, if %d, len %d", ifc, buf->len);
-  if (mg_ntohs(ethhdr->type == 0x888E)) {
+  if (ethhdr->type == mg_htons(0x888E)) {
 #if CONFIG_WPS2
     if (wps_rx_callback != NULL) wps_rx_callback(buf->data, buf->len);
 #endif

tutorials/udp/mdns-client/main.c

@@ -8,7 +8,8 @@ char s_theone[] = "Server.local";
 static void mdns_ev_handler(struct mg_connection *c, int ev, void *ev_data) {
   if (ev == MG_EV_MDNS_RESP) {  // is this the one ?
     struct mg_mdns_resp *resp = (struct mg_mdns_resp *) ev_data;
-    if (mg_strcasecmp(mg_str(s_theone), resp->name) == 0)
+    if (resp->rr->atype == MG_DNS_RTYPE_A &&
+        mg_strcasecmp(mg_str(s_theone), resp->name) == 0)
       MG_INFO(("%.*s is: %M", resp->name.len, resp->name.buf, mg_print_ip, &resp->addr));
   }
   (void) c;

tutorials/udp/mdns-sd-client/Makefile

@@ -0,0 +1,25 @@
+PROG ?= example                   # Program we are building
+DELETE = rm -rf                   # Command to remove files
+OUT ?= -o $(PROG)                 # Compiler argument for output file
+SOURCES = main.c mongoose.c       # Source code files
+CFLAGS = -W -Wall -Wextra -g -I.  # Build options
+
+# Mongoose build options. See https://mongoose.ws/documentation/#build-options
+CFLAGS_MONGOOSE += -DMG_ENABLE_LINES
+
+ifeq ($(OS),Windows_NT)   # Windows settings. Assume MinGW compiler. To use VC: make CC=cl CFLAGS=/MD OUT=/Feprog.exe
+  PROG ?= example.exe           # Use .exe suffix for the binary
+  CC = gcc                      # Use MinGW gcc compiler
+  CFLAGS += -lws2_32            # Link against Winsock library
+  DELETE = cmd /C del /Q /F /S  # Command prompt command to delete files
+  OUT ?= -o $(PROG)             # Build output
+endif
+
+all: $(PROG)              # Default target. Build and run program
+	$(RUN) ./$(PROG) $(ARGS)
+
+$(PROG): $(SOURCES)       # Build program from sources
+	$(CC) $(SOURCES) $(CFLAGS) $(CFLAGS_MONGOOSE) $(CFLAGS_EXTRA) $(OUT)
+
+clean:                    # Cleanup. Delete built program and all build artifacts
+	$(DELETE) $(PROG) *.o *.obj *.exe *.dSYM

tutorials/udp/mdns-sd-client/README.md

@@ -0,0 +1,43 @@
+
+Browses for `_http._tcp.local` services on the local network using mDNS/DNS-SD.
+
+```sh
+make
+cc main.c mongoose.c        -W -Wall -Wextra -g -I.   -DMG_ENABLE_LINES  -o example                                    
+./example                    
+1304aa594 3 net.c:311:mg_mgr_init       MG_IO_SIZE: 16384, TLS: none
+1304aa594 3 net.c:224:mg_listen         1 4 udp://224.0.0.251:5353
+1304aa594 3 sock.c:167:mg_send          1 4 0:0:0 34 err 0
+1304aa594 3 sock.c:361:read_conn        1 4 0:0:0 34 err 0
+1304aa594 3 dns.c:478:handle_mdns_query PTR request for _http._tcp
+1304aa5d0 3 sock.c:361:read_conn        1 4 0:0:0 289 err 0
+1304aa5d1 3 dns.c:703:handle_mdns_respo PTR response for _http._tcp.local from 3D03F3CPAU00096.local
+1304aa5d1 2 main.c:15:mdns_ev_handler   Got a response
+	SERVICE -> _http._tcp
+	NAME -> 3D03F3CPAU00096.local
+	PORT -> 80
+	TXT -> host=3D03F3CPAU00096mac=e0:50:8b:8d:2f:75ip=192.168.69.220
+	URL -> http://3D03F3CPAU00096.local:80
+
+1304aa622 3 sock.c:361:read_conn        1 4 0:0:0 226 err 0
+1304aa622 3 dns.c:703:handle_mdns_respo PTR response for _http._tcp.local from DIP-3TIR3020140717CCWR473261824.local
+1304aa622 2 main.c:15:mdns_ev_handler   Got a response
+	SERVICE -> _http._tcp
+	NAME -> DIP-3TIR3020140717CCWR473261824.local
+	PORT -> 80
+	ADDRESS -> 192.168.69.225
+	TXT -> path=/
+	URL -> http://192.168.69.225:80
+
+1304aa6f5 3 sock.c:361:read_conn        1 4 0:0:0 169 err 0
+1304aa6f5 3 dns.c:703:handle_mdns_respo PTR response for _http._tcp.local from PHILIPS_HD9255_3_6B7E5E.local
+1304aa6f5 2 main.c:15:mdns_ev_handler   Got a response
+	SERVICE -> _http._tcp
+	NAME -> PHILIPS_HD9255_3_6B7E5E.local
+	PORT -> 80
+	ADDRESS -> 192.168.69.167
+	TXT -> Device Type=Domestic Appliance
+	URL -> http://192.168.69.167:80
+
+```
+

tutorials/udp/mdns-sd-client/main.c

@@ -0,0 +1,58 @@
+// Copyright (c) 2026 Cesanta Software Limited
+// All rights reserved
+
+#include "mongoose.h"
+
+static char s_name[] = "Mongoose";
+static char s_service[] = "_http._tcp";
+
+static void mdns_ev_handler(struct mg_connection *c, int ev, void *ev_data) {
+  if (ev == MG_EV_MDNS_RESP) {
+    struct mg_mdns_resp *resp = (struct mg_mdns_resp *) ev_data;
+    if (resp->rr->atype == MG_DNS_RTYPE_PTR &&
+        mg_strcasecmp(mg_str(s_service), resp->sd.srvcproto) == 0) {
+      char addr[40];
+      MG_INFO(("Got a response"));
+      printf("\tSERVICE -> %.*s\n", (int) resp->sd.srvcproto.len,
+             resp->sd.srvcproto.buf);
+      printf("\tNAME -> %.*s\n", (int) resp->name.len, resp->name.buf);
+      if (resp->sd.port != 0)
+        printf("\tPORT -> %u\n", resp->sd.port);
+      if (resp->addr.addr.ip4 != 0) {
+        mg_snprintf(addr, sizeof(addr), "%M", mg_print_ip, &resp->addr);
+        printf("\tADDRESS -> %s\n", addr);
+      }
+      if (resp->sd.txt.buf != NULL)
+        printf("\tTXT -> %.*s\n", (int) resp->sd.txt.len, resp->sd.txt.buf);
+      if (resp->addr.addr.ip4 != 0 && resp->addr.port != 0) {
+        mg_snprintf(addr, sizeof(addr), "http://%M:%u", mg_print_ip, &resp->addr,
+                    mg_ntohs(resp->addr.port));
+        printf("\tURL -> %s\n", addr);
+      } else if (resp->sd.port != 0 && resp->name.buf != NULL) {
+        printf("\tURL -> http://%.*s:%u\n", (int) resp->name.len,
+               resp->name.buf, resp->sd.port);
+      }
+      printf("\n");
+    }
+  }
+  (void) c;
+}
+
+int main(void) {
+  struct mg_mgr mgr;
+  char query[256];
+  static struct mg_connection *c;
+  mg_log_set(MG_LL_DEBUG);  // Set log level
+  mg_mgr_init(&mgr);        // Initialise event manager
+
+  c = mg_mdns_listen(&mgr, mdns_ev_handler, s_name);  // Start mDNS server
+  if (c == NULL) return 1;
+  mg_snprintf(query, sizeof(query), "%s.local", s_service);
+   // Request service providers
+  if (!mg_mdns_query(c, query, MG_DNS_RTYPE_PTR)) return 1;
+
+  for (;;) mg_mgr_poll(&mgr, 1000);  // Event loop
+
+  mg_mgr_free(&mgr);
+  return 0;
+}

tutorials/udp/mdns-sd-client/mongoose.c

@@ -0,0 +1 @@
+../../../mongoose.c

tutorials/udp/mdns-sd-client/mongoose.h

@@ -0,0 +1 @@
+../../../mongoose.h