Implemented OpenSSL providers support

CMakeLists.txt

@@ -17,7 +17,7 @@
 
 cmake_minimum_required(VERSION 3.5)
 
-project("Eclipse Paho C" 
+project("Eclipse Paho C"
   VERSION 1.3.13
   LANGUAGES C
 )
@@ -29,7 +29,7 @@ set(CMAKE_SCRIPTS "${CMAKE_SOURCE_DIR}/cmake")
 set(CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/cmake/modules")
 
 ## Project Version
-## Previously we read in the version from these files, but now we use the 
+## Previously we read in the version from these files, but now we use the
 ## CMake project setting. We just make sure the files and CMake match.
 file(READ version.major PAHO_VERSION_MAJOR)
 file(READ version.minor PAHO_VERSION_MINOR)
@@ -64,6 +64,7 @@ option(PAHO_ENABLE_TESTING "Build tests and run" TRUE)
 option(PAHO_ENABLE_CPACK "Enable CPack" TRUE)
 option(PAHO_HIGH_PERFORMANCE "Disable tracing and heap tracking" FALSE)
 option(PAHO_USE_SELECT "Revert to select system call instead of poll" FALSE)
+option(PAHO_SSL_PROVIDERS "Enable provider option for OpenSSL" FALSE)
 
 if(PAHO_HIGH_PERFORMANCE)
   add_definitions(-DHIGH_PERFORMANCE=1)
@@ -73,6 +74,10 @@ if(PAHO_USE_SELECT)
   add_definitions(-DUSE_SELECT=1)
 endif()
 
+if(PAHO_SSL_PROVIDERS)
+  add_definitions(-DOPENSSL_PROVIDERS=1)
+endif()
+
 if(PAHO_WITH_LIBUUID)
   add_definitions(-DUSE_LIBUUID=1)
 endif()

src/MQTTAsync.c

@@ -599,7 +599,7 @@ int MQTTAsync_connect(MQTTAsync handle, const MQTTAsync_connectOptions* options)
 	}
 	if (options->struct_version != 0 && options->ssl) /* check validity of SSL options structure */
 	{
-		if (strncmp(options->ssl->struct_id, "MQTS", 4) != 0 || options->ssl->struct_version < 0 || options->ssl->struct_version > 5)
+		if (strncmp(options->ssl->struct_id, "MQTS", 4) != 0 || options->ssl->struct_version < 0 || options->ssl->struct_version > 6)
 		{
 			rc = MQTTASYNC_BAD_STRUCTURE;
 			goto exit;
@@ -757,6 +757,11 @@ int MQTTAsync_connect(MQTTAsync handle, const MQTTAsync_connectOptions* options)
 			if (m->c->sslopts->CApath)
 				free((void*)m->c->sslopts->CApath);
 		}
+		if (m->c->sslopts->struct_version >= 6)
+		{
+			if (m->c->sslopts->providerName)
+				free((void*)m->c->sslopts->providerName);
+		}
 		free((void*)m->c->sslopts);
 		m->c->sslopts = NULL;
 	}
@@ -806,6 +811,17 @@ int MQTTAsync_connect(MQTTAsync handle, const MQTTAsync_connectOptions* options)
 				m->c->sslopts->protos = (const unsigned char*)MQTTStrdup((const char*)options->ssl->protos);
 			m->c->sslopts->protos_len = options->ssl->protos_len;
 		}
+		if (m->c->sslopts->struct_version >= 6)
+		{
+			if (options->ssl->providerName) {
+# if OPENSSL_PROVIDERS
+				m->c->sslopts->providerName = MQTTStrdup(options->ssl->providerName);
+# else // OPENSSL_PROVIDERS
+				rc = MQTTASYNC_SSL_NOT_SUPPORTED;
+				goto exit;
+# endif // OPENSSL_PROVIDERS
+			}
+		}
 	}
 #else
 	if (options->struct_version != 0 && options->ssl)

src/MQTTAsync.h

@@ -491,7 +491,7 @@ typedef struct
 #define MQTTAsync_connectData_initializer {{'M', 'Q', 'C', 'D'}, 0, NULL, {0, NULL}}
 
 /**
- * This is a callback function which will allow the client application to update the 
+ * This is a callback function which will allow the client application to update the
  * connection data.
  * @param data The connection data which can be modified by the application.
  * @return Return a non-zero value to update the connect data, zero to keep the same data.
@@ -1073,12 +1073,13 @@ typedef struct
 	/** The eyecatcher for this structure.  Must be MQTS */
 	char struct_id[4];
 
-	/** The version number of this structure. Must be 0, 1, 2, 3, 4 or 5.
+	/** The version number of this structure. Must be [0-6].
 	 * 0 means no sslVersion
 	 * 1 means no verify, CApath
 	 * 2 means no ssl_error_context, ssl_error_cb
 	 * 3 means no ssl_psk_cb, ssl_psk_context, disableDefaultTrustStore
 	 * 4 means no protos, protos_len
+   * 5 means no providerName
 	 */
 	int struct_version;
 
@@ -1177,9 +1178,13 @@ typedef struct
 	 * Exists only if struct_version >= 5
 	 */
 	unsigned int protos_len;
+
+	/** OpenSSL provider to used, NULL if disabled. */
+	const char* providerName;
+
 } MQTTAsync_SSLOptions;
 
-#define MQTTAsync_SSLOptions_initializer { {'M', 'Q', 'T', 'S'}, 5, NULL, NULL, NULL, NULL, NULL, 1, MQTT_SSL_VERSION_DEFAULT, 0, NULL, NULL, NULL, NULL, NULL, 0, NULL, 0 }
+#define MQTTAsync_SSLOptions_initializer { {'M', 'Q', 'T', 'S'}, 6, NULL, NULL, NULL, NULL, NULL, 1, MQTT_SSL_VERSION_DEFAULT, 0, NULL, NULL, NULL, NULL, NULL, 0, NULL, 0, NULL }
 
 /** Utility structure where name/value pairs are needed */
 typedef struct

src/MQTTClient.c

@@ -1285,7 +1285,7 @@ static MQTTResponse MQTTClient_connectURIVersion(MQTTClient handle, MQTTClient_c
 			setSocketForSSLrc = SSLSocket_setSocketForSSL(&m->c->net, m->c->sslopts,
 				serverURI, hostname_len);
 
-			if (setSocketForSSLrc != MQTTCLIENT_SUCCESS)
+			if (1 == setSocketForSSLrc)
 			{
 				if (m->c->session != NULL)
 					if ((rc = SSL_set_session(m->c->net.ssl, m->c->session)) != 1)
@@ -1618,6 +1618,11 @@ static MQTTResponse MQTTClient_connectURI(MQTTClient handle, MQTTClient_connectO
 			if (m->c->sslopts->CApath)
 				free((void*)m->c->sslopts->CApath);
 		}
+		if (m->c->sslopts->struct_version >= 6)
+		{
+			if (m->c->sslopts->providerName)
+				free((void*)m->c->sslopts->providerName);
+		}
 		free(m->c->sslopts);
 		m->c->sslopts = NULL;
 	}
@@ -1666,6 +1671,17 @@ static MQTTResponse MQTTClient_connectURI(MQTTClient handle, MQTTClient_connectO
 		    m->c->sslopts->protos = options->ssl->protos;
 		    m->c->sslopts->protos_len = options->ssl->protos_len;
 		}
+		if (m->c->sslopts->struct_version >= 6)
+		{
+			if (options->ssl->providerName) {
+# if OPENSSL_PROVIDERS
+				m->c->sslopts->providerName = MQTTStrdup(options->ssl->providerName);
+# else // OPENSSL_PROVIDERS
+				rc.reasonCode = MQTTCLIENT_SSL_NOT_SUPPORTED;
+				goto exit;
+# endif // OPENSSL_PROVIDERS
+			}
+		}
 	}
 #endif
 
@@ -1818,7 +1834,7 @@ MQTTResponse MQTTClient_connectAll(MQTTClient handle, MQTTClient_connectOptions*
 #if defined(OPENSSL)
 	if (options->struct_version != 0 && options->ssl) /* check validity of SSL options structure */
 	{
-		if (strncmp(options->ssl->struct_id, "MQTS", 4) != 0 || options->ssl->struct_version < 0 || options->ssl->struct_version > 5)
+		if (strncmp(options->ssl->struct_id, "MQTS", 4) != 0 || options->ssl->struct_version < 0 || options->ssl->struct_version > 6)
 		{
 			rc.reasonCode = MQTTCLIENT_BAD_STRUCTURE;
 			goto exit;

src/MQTTClient.h

@@ -675,12 +675,13 @@ typedef struct
 	/** The eyecatcher for this structure.  Must be MQTS */
 	char struct_id[4];
 
-	/** The version number of this structure. Must be 0, 1, 2, 3, 4 or 5.
+	/** The version number of this structure. Must be [0-6].
 	 * 0 means no sslVersion
 	 * 1 means no verify, CApath
 	 * 2 means no ssl_error_context, ssl_error_cb
 	 * 3 means no ssl_psk_cb, ssl_psk_context, disableDefaultTrustStore
 	 * 4 means no protos, protos_len
+   * 5 means no providerName
 	 */
 	int struct_version;
 
@@ -779,9 +780,13 @@ typedef struct
 	 * Exists only if struct_version >= 5
 	 */
 	unsigned int protos_len;
+
+	/** OpenSSL provider to used, NULL if disabled. */
+	const char* providerName;
+
 } MQTTClient_SSLOptions;
 
-#define MQTTClient_SSLOptions_initializer { {'M', 'Q', 'T', 'S'}, 5, NULL, NULL, NULL, NULL, NULL, 1, MQTT_SSL_VERSION_DEFAULT, 0, NULL, NULL, NULL, NULL, NULL, 0, NULL, 0 }
+#define MQTTClient_SSLOptions_initializer { {'M', 'Q', 'T', 'S'}, 5, NULL, NULL, NULL, NULL, NULL, 1, MQTT_SSL_VERSION_DEFAULT, 0, NULL, NULL, NULL, NULL, NULL, 0, NULL, 0 , NULL}
 
 /**
   * MQTTClient_libraryInfo is used to store details relating to the currently used

src/MQTTProtocolClient.c

@@ -345,7 +345,7 @@ int MQTTProtocol_handlePublishes(void* pack, SOCKET sock)
 	if (publish->header.bits.qos == 1)
 	{
 		Protocol_processPublication(publish, client, 1);
-  
+
 		if (socketHasPendingWrites)
 			rc = MQTTProtocol_queueAck(client, PUBACK, publish->msgId);
 		else
@@ -981,8 +981,13 @@ void MQTTProtocol_freeClient(Clients* client)
 			if (client->sslopts->protos)
 				free((void*)client->sslopts->protos);
 		}
+		if (client->sslopts->struct_version >= 6)
+		{
+			if(client->sslopts->providerName)
+				free((void*)client->sslopts->providerName);
+		}
 		free(client->sslopts);
-			client->sslopts = NULL;
+		client->sslopts = NULL;
 	}
 #endif
 	/* don't free the client structure itself... this is done elsewhere */

src/SSLSocket.c

@@ -44,6 +44,16 @@
 #include <openssl/crypto.h>
 #include <openssl/x509v3.h>
 
+#if OPENSSL_PROVIDERS
+# include <openssl/store.h>
+# include <openssl/provider.h>
+
+# if (OPENSSL_VERSION_NUMBER < 0x030000000lu)
+#  error "OpenSSL providers are only usabe with OpenSSL version 3.x.x."
+# endif // (OPENSSL_VERSION_NUMBER < 0x030000000lu)
+
+#endif // OPENSSL_PROVIDERS
+
 extern Sockets mod_s;
 
 static int SSLSocket_error(char* aString, SSL* ssl, SOCKET sock, int rc, int (*cb)(const char *str, size_t len, void *u), void* u);
@@ -619,16 +629,108 @@ int SSLSocket_createContext(networkHandles* net, MQTTClient_SSLOptions* opts)
 			SSL_CTX_set_default_passwd_cb_userdata(net->ctx, (void*)opts->privateKeyPassword);
 		}
 
+#if OPENSSL_PROVIDERS
 		/* support for ASN.1 == DER format? DER can contain only one certificate? */
-		rc = SSL_CTX_use_PrivateKey_file(net->ctx, opts->privateKey, SSL_FILETYPE_PEM);
-		if (opts->privateKey == opts->keyStore)
-			opts->privateKey = NULL;
+		if(opts->providerName && (opts->providerName[0] != '\0'))
+		{
+			// Load desired OpenSSL provider, e.g. tpm2.
+			OSSL_PROVIDER *provider = OSSL_PROVIDER_load(NULL, opts->providerName);
+			if(!provider)
+			{
+				rc = 0;
+				goto free_ctx;
+			}
+
+			// Perform providers Self-Test.
+			rc = OSSL_PROVIDER_self_test(provider);
+			if(rc != 1)
+			{
+				OSSL_PROVIDER_unload(provider);
+				goto free_ctx;
+			}
+
+			// Open STORE context with given providers handle.
+			OSSL_STORE_CTX *storeCtx = OSSL_STORE_open(opts->privateKey, NULL, NULL, NULL, NULL);
+			if (!storeCtx) {
+				OSSL_PROVIDER_unload(provider);
+				rc = 0;
+				goto free_ctx;
+			}
+
+			rc = OSSL_STORE_expect(storeCtx, OSSL_STORE_INFO_PKEY);
+			if (rc != 1) {
+				OSSL_STORE_close(storeCtx);
+				OSSL_PROVIDER_unload(provider);
+				rc = 0;
+				goto free_ctx;
+			}
+
+			EVP_PKEY *pkey = NULL;
+			while (pkey == NULL && !OSSL_STORE_eof(storeCtx)) {
+				// Load STORE context and get it's type.
+				OSSL_STORE_INFO *info = OSSL_STORE_load(storeCtx);
+
+				// This can happen when, for example, we're reaching stuff that's not there
+				// or there is a thing that we don't expect.
+				// If happens, then we just loop until EOF.
+				if (info == NULL) {
+					continue;
+				}
+
+				const int type = OSSL_STORE_INFO_get_type(info);
+				if (type == OSSL_STORE_INFO_PKEY) {
+					// If type is private key, fetch it.
+					pkey = OSSL_STORE_INFO_get1_PKEY(info);
+				} else {
+					break;
+				}
+
+				OSSL_STORE_INFO_free(info);
+			}
+
+			// If private key is invalid - exit.
+			if (!pkey) {
+				OSSL_STORE_close(storeCtx);
+				OSSL_PROVIDER_unload(provider);
+				rc = 0;
+				goto free_ctx;
+			}
+
+			// Load private key handle to ctx.
+			rc = SSL_CTX_use_PrivateKey(net->ctx, pkey);
+			if (rc != 1)
+			{
+				if (opts->struct_version >= 3)
+					SSLSocket_error("SSL_CTX_use_PrivateKey", NULL, net->socket, rc, opts->ssl_error_cb, opts->ssl_error_context);
+				else
+					SSLSocket_error("SSL_CTX_use_PrivateKey", NULL, net->socket, rc, NULL, NULL);
+				goto free_ctx;
+			}
+		}
+		else
+#endif // OPENSSL_PROVIDERS
+		{
+			rc = SSL_CTX_use_PrivateKey_file(net->ctx, opts->privateKey, SSL_FILETYPE_PEM);
+			if (opts->privateKey == opts->keyStore)
+				opts->privateKey = NULL;
+			if (rc != 1)
+			{
+				if (opts->struct_version >= 3)
+					SSLSocket_error("SSL_CTX_use_PrivateKey_file", NULL, net->socket, rc, opts->ssl_error_cb, opts->ssl_error_context);
+				else
+					SSLSocket_error("SSL_CTX_use_PrivateKey_file", NULL, net->socket, rc, NULL, NULL);
+				goto free_ctx;
+			}
+		}
+
+		// Check if private kay matches certificate.
+		rc = SSL_CTX_check_private_key(net->ctx);
 		if (rc != 1)
 		{
 			if (opts->struct_version >= 3)
-				SSLSocket_error("SSL_CTX_use_PrivateKey_file", NULL, net->socket, rc, opts->ssl_error_cb, opts->ssl_error_context);
+				SSLSocket_error("SSL_CTX_check_private_key", NULL, net->socket, rc, opts->ssl_error_cb, opts->ssl_error_context);
 			else
-				SSLSocket_error("SSL_CTX_use_PrivateKey_file", NULL, net->socket, rc, NULL, NULL);
+				SSLSocket_error("SSL_CTX_check_private_key", NULL, net->socket, rc, NULL, NULL);
 			goto free_ctx;
 		}
 	}
@@ -721,8 +823,9 @@ int SSLSocket_setSocketForSSL(networkHandles* net, MQTTClient_SSLOptions* opts,
 
 		SSL_CTX_set_info_callback(net->ctx, SSL_CTX_info_callback);
 		SSL_CTX_set_msg_callback(net->ctx, SSL_CTX_msg_callback);
-   		if (opts->enableServerCertAuth)
+   		if (opts->enableServerCertAuth) {
 			SSL_CTX_set_verify(net->ctx, SSL_VERIFY_PEER, NULL);
+		}
 
 		net->ssl = SSL_new(net->ctx);
 
@@ -773,8 +876,7 @@ int SSLSocket_connect(SSL* ssl, SOCKET sock, const char* hostname, int verify, i
 	rc = SSL_connect(ssl);
 	if (rc != 1)
 	{
-		int error;
-		error = SSLSocket_error("SSL_connect", ssl, sock, rc, cb, u);
+		int error = SSLSocket_error("SSL_connect", ssl, sock, rc, cb, u);
 		if (error == SSL_FATAL)
 			rc = error;
 		if (error == SSL_ERROR_WANT_READ || error == SSL_ERROR_WANT_WRITE)
@@ -1042,7 +1144,7 @@ int SSLSocket_putdatas(SSL* ssl, SOCKET socket, char* buf0, size_t buf0len, Pack
 		    	free(bufs.buffers[i]);
 		    	bufs.buffers[i] = NULL;
 		    }
-		}	
+		}
 	}
 exit:
 	FUNC_EXIT_RC(rc);