Moved HTTP client, ssl and some util code into separate files

build/src/ssl.c

@@ -0,0 +1,179 @@
+#include "internal.h"
+
+#if !defined(NO_SSL)
+// set_ssl_option() function updates this array.
+// It loads SSL library dynamically and changes NULLs to the actual addresses
+// of respective functions. The macros above (like SSL_connect()) are really
+// just calling these functions indirectly via the pointer.
+static struct ssl_func ssl_sw[] = {
+  {"SSL_free",   NULL},
+  {"SSL_accept",   NULL},
+  {"SSL_connect",   NULL},
+  {"SSL_read",   NULL},
+  {"SSL_write",   NULL},
+  {"SSL_get_error",  NULL},
+  {"SSL_set_fd",   NULL},
+  {"SSL_new",   NULL},
+  {"SSL_CTX_new",   NULL},
+  {"SSLv23_server_method", NULL},
+  {"SSL_library_init",  NULL},
+  {"SSL_CTX_use_PrivateKey_file", NULL},
+  {"SSL_CTX_use_certificate_file",NULL},
+  {"SSL_CTX_set_default_passwd_cb",NULL},
+  {"SSL_CTX_free",  NULL},
+  {"SSL_load_error_strings", NULL},
+  {"SSL_CTX_use_certificate_chain_file", NULL},
+  {"SSLv23_client_method", NULL},
+  {"SSL_pending", NULL},
+  {"SSL_CTX_set_verify", NULL},
+  {"SSL_shutdown",   NULL},
+  {NULL,    NULL}
+};
+
+// Similar array as ssl_sw. These functions could be located in different lib.
+static struct ssl_func crypto_sw[] = {
+  {"CRYPTO_num_locks",  NULL},
+  {"CRYPTO_set_locking_callback", NULL},
+  {"CRYPTO_set_id_callback", NULL},
+  {"ERR_get_error",  NULL},
+  {"ERR_error_string", NULL},
+  {NULL,    NULL}
+};
+
+static pthread_mutex_t *ssl_mutexes;
+
+static int sslize(struct mg_connection *conn, SSL_CTX *s, int (*func)(SSL *)) {
+  return (conn->ssl = SSL_new(s)) != NULL &&
+    SSL_set_fd(conn->ssl, conn->client.sock) == 1 &&
+    func(conn->ssl) == 1;
+}
+
+// Return OpenSSL error message
+static const char *ssl_error(void) {
+  unsigned long err;
+  err = ERR_get_error();
+  return err == 0 ? "" : ERR_error_string(err, NULL);
+}
+
+static void ssl_locking_callback(int mode, int mutex_num, const char *file,
+                                 int line) {
+  (void) line;
+  (void) file;
+
+  if (mode & 1) {  // 1 is CRYPTO_LOCK
+    (void) pthread_mutex_lock(&ssl_mutexes[mutex_num]);
+  } else {
+    (void) pthread_mutex_unlock(&ssl_mutexes[mutex_num]);
+  }
+}
+
+static unsigned long ssl_id_callback(void) {
+  return (unsigned long) pthread_self();
+}
+
+#if !defined(NO_SSL_DL)
+static int load_dll(struct mg_context *ctx, const char *dll_name,
+                    struct ssl_func *sw) {
+  union {void *p; void (*fp)(void);} u;
+  void  *dll_handle;
+  struct ssl_func *fp;
+
+  if ((dll_handle = dlopen(dll_name, RTLD_LAZY)) == NULL) {
+    cry(fc(ctx), "%s: cannot load %s", __func__, dll_name);
+    return 0;
+  }
+
+  for (fp = sw; fp->name != NULL; fp++) {
+#ifdef _WIN32
+    // GetProcAddress() returns pointer to function
+    u.fp = (void (*)(void)) dlsym(dll_handle, fp->name);
+#else
+    // dlsym() on UNIX returns void *. ISO C forbids casts of data pointers to
+    // function pointers. We need to use a union to make a cast.
+    u.p = dlsym(dll_handle, fp->name);
+#endif // _WIN32
+    if (u.fp == NULL) {
+      cry(fc(ctx), "%s: %s: cannot find %s", __func__, dll_name, fp->name);
+      return 0;
+    } else {
+      fp->ptr = u.fp;
+    }
+  }
+
+  return 1;
+}
+#endif // NO_SSL_DL
+
+// Dynamically load SSL library. Set up ctx->ssl_ctx pointer.
+static int set_ssl_option(struct mg_context *ctx) {
+  int i, size;
+  const char *pem;
+
+  // If PEM file is not specified and the init_ssl callback
+  // is not specified, skip SSL initialization.
+  if ((pem = ctx->config[SSL_CERTIFICATE]) == NULL) {
+    //  MG_INIT_SSL
+    //  ctx->callbacks.init_ssl == NULL) {
+    return 1;
+  }
+
+#if !defined(NO_SSL_DL)
+  if (!load_dll(ctx, SSL_LIB, ssl_sw) ||
+      !load_dll(ctx, CRYPTO_LIB, crypto_sw)) {
+    return 0;
+  }
+#endif // NO_SSL_DL
+
+  // Initialize SSL library
+  SSL_library_init();
+  SSL_load_error_strings();
+
+  if ((ctx->ssl_ctx = SSL_CTX_new(SSLv23_server_method())) == NULL) {
+    cry(fc(ctx), "SSL_CTX_new (server) error: %s", ssl_error());
+    return 0;
+  }
+
+  // If user callback returned non-NULL, that means that user callback has
+  // set up certificate itself. In this case, skip sertificate setting.
+  // MG_INIT_SSL
+  if (SSL_CTX_use_certificate_file(ctx->ssl_ctx, pem, 1) == 0 ||
+      SSL_CTX_use_PrivateKey_file(ctx->ssl_ctx, pem, 1) == 0) {
+    cry(fc(ctx), "%s: cannot open %s: %s", __func__, pem, ssl_error());
+    return 0;
+  }
+
+  if (pem != NULL) {
+    (void) SSL_CTX_use_certificate_chain_file(ctx->ssl_ctx, pem);
+  }
+
+  // Initialize locking callbacks, needed for thread safety.
+  // http://www.openssl.org/support/faq.html#PROG1
+  size = sizeof(pthread_mutex_t) * CRYPTO_num_locks();
+  if ((ssl_mutexes = (pthread_mutex_t *) malloc((size_t)size)) == NULL) {
+    cry(fc(ctx), "%s: cannot allocate mutexes: %s", __func__, ssl_error());
+    return 0;
+  }
+
+  for (i = 0; i < CRYPTO_num_locks(); i++) {
+    pthread_mutex_init(&ssl_mutexes[i], NULL);
+  }
+
+  CRYPTO_set_locking_callback(&ssl_locking_callback);
+  CRYPTO_set_id_callback(&ssl_id_callback);
+
+  return 1;
+}
+
+static void uninitialize_ssl(struct mg_context *ctx) {
+  int i;
+  if (ctx->ssl_ctx != NULL) {
+    CRYPTO_set_locking_callback(NULL);
+    for (i = 0; i < CRYPTO_num_locks(); i++) {
+      pthread_mutex_destroy(&ssl_mutexes[i]);
+    }
+    CRYPTO_set_locking_callback(NULL);
+    CRYPTO_set_id_callback(NULL);
+  }
+}
+#endif // !NO_SSL
+