Improve SNI

examples/http-client/Makefile

@@ -1,13 +1,16 @@
 PROG ?= example
-CFLAGS ?= -DMG_ENABLE_LINES $(CFLAGS_EXTRA)
-MBEDTLS_DIR ?=
+CFLAGS ?= -DMG_ENABLE_LINES $(EXTRA)
 
-ifeq "$(MBEDTLS_DIR)" ""
-else
+ifneq ($(MBEDTLS),)
 CFLAGS += -DMG_ENABLE_MBEDTLS=1 -I$(MBEDTLS_DIR)/include -I/usr/include
 CFLAGS += -L$(MBEDTLS_DIR)/lib -lmbedtls -lmbedcrypto -lmbedx509
 endif
 
+ifneq ($(OPENSSL),)
+CFLAGS += -DMG_ENABLE_OPENSSL=1 -I$(OPENSSL)/include
+CFLAGS += -L$(OPENSSL)/lib -lssl -lcrypto
+endif
+
 all: $(PROG)
 	$(DEBUGGER) ./$(PROG) $(ARGS)
 

examples/http-client/main.c

@@ -1,43 +1,53 @@
-// Copyright (c) 2020 Cesanta Software Limited
+// Copyright (c) 2021 Cesanta Software Limited
 // All rights reserved
 //
 // Example HTTP client. Connect to `s_url`, send request, wait for a response,
 // print the response and exit.
+// You can change `s_url` from the command line by executing: ./example YOUR_URL
 //
 // To enable SSL/TLS for this client, build it like this:
-//    make MBEDTLS_DIR=/path/to/your/mbedtls/installation
+//    make MBEDTLS=/path/to/your/mbedtls/installation
+//    make OPENSSL=/path/to/your/openssl/installation
 
 #include "mongoose.h"
 
-// The very first web page in history
+// The very first web page in history. You can replace it from command line
 static const char *s_url = "http://info.cern.ch";
 
 // Print HTTP response and signal that we're done
 static void fn(struct mg_connection *c, int ev, void *ev_data, void *fn_data) {
   if (ev == MG_EV_CONNECT) {
-    // Connected to server
+    // Connected to server. Extract host name from URL
     struct mg_str host = mg_url_host(s_url);
 
+    // If s_url is https://, tell client connection to use TLS
     if (mg_url_is_ssl(s_url)) {
-      // If s_url is https://, tell client connection to use TLS
-      struct mg_tls_opts opts = {.ca = "ca.pem"};
+      // struct mg_tls_opts opts = {.ca = "ca.pem", .srvname = host};
+      struct mg_tls_opts opts = {.ca = "ca.pem", .srvname = mg_str("x")};
       mg_tls_init(c, &opts);
     }
+
     // Send request
-    mg_printf(c, "GET %s HTTP/1.0\r\nHost: %.*s\r\n\r\n", mg_url_uri(s_url),
-              (int) host.len, host.ptr);
+    mg_printf(c,
+              "GET %s HTTP/1.0\r\n"
+              "Host: %.*s\r\n"
+              "\r\n",
+              mg_url_uri(s_url), (int) host.len, host.ptr);
   } else if (ev == MG_EV_HTTP_MSG) {
     // Response is received. Print it
     struct mg_http_message *hm = (struct mg_http_message *) ev_data;
     printf("%.*s", (int) hm->message.len, hm->message.ptr);
     c->is_closing = 1;         // Tell mongoose to close this connection
     *(bool *) fn_data = true;  // Tell event loop to stop
+  } else if (ev == MG_EV_ERROR) {
+    *(bool *) fn_data = true;  // Error, tell event loop to stop
   }
 }
 
-int main(void) {
+int main(int argc, char *argv[]) {
   struct mg_mgr mgr;                        // Event manager
   bool done = false;                        // Event handler flips it to true
+  if (argc > 1) s_url = argv[1];            // Use URL from command line
   mg_log_set("3");                          // Set to 0 to disable debug
   mg_mgr_init(&mgr);                        // Initialise event manager
   mg_http_connect(&mgr, s_url, fn, &done);  // Create client connection