IPv6 support

src/datum_api.c

@@ -1128,6 +1128,20 @@ enum MHD_Result datum_api_answer(void *cls, struct MHD_Connection *connection, c
 	return ret;
 }
 
+static struct MHD_Daemon *datum_api_try_start(unsigned int flags) {
+	flags |= MHD_USE_AUTO;  // event loop API
+	flags |= MHD_USE_INTERNAL_POLLING_THREAD;
+	return MHD_start_daemon(
+	                          flags,
+	                          datum_config.api_listen_port,
+	                          NULL, NULL,  // accept policy filter
+	                          &datum_api_answer, NULL,  // default URI handler
+	                          MHD_OPTION_CONNECTION_LIMIT, 128,
+	                          MHD_OPTION_NOTIFY_COMPLETED, datum_api_request_completed, NULL,
+	                          MHD_OPTION_LISTENING_ADDRESS_REUSE, (unsigned int)1,
+	                          MHD_OPTION_END);
+}
+
 void *datum_api_thread(void *ptr) {
 	struct MHD_Daemon *daemon;
 
@@ -1136,10 +1150,8 @@ void *datum_api_thread(void *ptr) {
 		return NULL;
 	}
 
-	daemon = MHD_start_daemon(MHD_USE_AUTO | MHD_USE_INTERNAL_POLLING_THREAD, datum_config.api_listen_port, NULL, NULL, &datum_api_answer, NULL,
-	                          MHD_OPTION_CONNECTION_LIMIT, 128,
-	                          MHD_OPTION_NOTIFY_COMPLETED, datum_api_request_completed, NULL,
-	                          MHD_OPTION_END);
+	daemon = datum_api_try_start(MHD_USE_DUAL_STACK);
+	if (!daemon) daemon = datum_api_try_start(0);
 
 	if (!daemon) {
 		DLOG_FATAL("Unable to start daemon for API");

src/datum_sockets.c

@@ -537,18 +537,39 @@ int assign_to_thread(T_DATUM_SOCKET_APP *app, int fd) {
 	return 1;
 }
 
+const char *datum_sockets_setup_listen_sock(const int listen_sock, const struct sockaddr * const sa, const size_t sa_len) {
+	if (-1 == listen_sock) {
+		return "Could not create listening socket";
+	}
+
+	datum_socket_setoptions(listen_sock);
+
+	static const int reuse = 1;
+	if (setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR, (const char*)&reuse, sizeof(reuse)) < 0) {
+		return "setsockopt(SO_REUSEADDR) failed";
+	}
+
+	if (bind(listen_sock, sa, sa_len) < 0) {
+		return "bind failed";
+	}
+
+	if (listen(listen_sock, 10) < 0) {
+		return "listen failed";
+	}
+
+	return NULL;
+}
+
 void *datum_gateway_listener_thread(void *arg) {
-	struct sockaddr_in serveraddr;
 	int i, ret;
-	int reuse = 1;
 	bool rejecting_now = false;
 	uint64_t last_reject_msg_tsms = 0, curtime_tsms = 0;
 	uint64_t reject_count = 0;
 
 	T_DATUM_SOCKET_APP *app = (T_DATUM_SOCKET_APP *)arg;
 
 	struct epoll_event ev, events[MAX_EVENTS];
-	int listen_sock, conn_sock, nfds, epollfd;
+	int listen_socks[2], conn_sock, nfds, epollfd;
 
 	if (!app) {
 		DLOG_FATAL("Called without application data structure. :(");
@@ -577,37 +598,36 @@ void *datum_gateway_listener_thread(void *arg) {
 
 	app->datum_active_threads = 0;
 
-	listen_sock = socket(AF_INET, SOCK_STREAM, 0);
-	if (!listen_sock) {
-		DLOG_FATAL("Could get socket: %s", strerror(errno));
-		panic_from_thread(__LINE__);
-		return NULL;
-	}
-
-	datum_socket_setoptions(listen_sock);
-	memset(&serveraddr, 0, sizeof(serveraddr));
-	serveraddr.sin_family = AF_INET;
-	serveraddr.sin_port = htons(app->listen_port);
-
-	// TODO: Add option to bind to specific IP per configuration!
-	serveraddr.sin_addr.s_addr = INADDR_ANY;
-
-	if (setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR, (const char*)&reuse, sizeof(reuse)) < 0) {
-		DLOG_FATAL("setsockopt(SO_REUSEADDR) failed: %s", strerror(errno));
-		panic_from_thread(__LINE__);
-		return NULL;
+	const struct sockaddr_in6 anyaddr6 = {
+		.sin6_family = AF_INET6,
+		.sin6_port = htons(app->listen_port),
+		.sin6_addr = IN6ADDR_ANY_INIT,
+	};
+	listen_socks[0] = socket(AF_INET6, SOCK_STREAM, 0);
+	const char * const errstr6 = datum_sockets_setup_listen_sock(listen_socks[0], (const struct sockaddr *)&anyaddr6, sizeof(anyaddr6));
+	const int errno6 = errno;
+	if (errstr6 && listen_socks[0] != -1) {
+		close(listen_socks[0]);
+		listen_socks[0] = -1;
 	}
 
-	if(bind(listen_sock, (struct sockaddr*)&serveraddr, sizeof(serveraddr)) < 0) {
-		DLOG_FATAL("bind failed: %s", strerror(errno));
+	const struct sockaddr_in anyaddr4 = {
+		.sin_family = AF_INET,
+		.sin_port = htons(app->listen_port),
+		.sin_addr.s_addr = INADDR_ANY,
+	};
+	listen_socks[1] = socket(AF_INET, SOCK_STREAM, 0);
+	const char *errstr = datum_sockets_setup_listen_sock(listen_socks[1], (const struct sockaddr *)&anyaddr4, sizeof(anyaddr4));
+	if (errstr && errstr6) {
+		const int errno4 = errno;
+		DLOG_FATAL("%s (IPv6): %s", errstr6, strerror(errno6));
+		DLOG_FATAL("%s (IPv4): %s", errstr, strerror(errno4));
 		panic_from_thread(__LINE__);
 		return NULL;
 	}
-
-	if (listen(listen_sock, 10) < 0) {
-		DLOG_FATAL("listen failed: %s", strerror(errno));
-		panic_from_thread(__LINE__);
-		return NULL;
+	if (errstr && listen_socks[1] != -1) {
+		close(listen_socks[1]);
+		listen_socks[1] = -1;
 	}
 
 	epollfd = epoll_create1(0);
@@ -617,12 +637,15 @@ void *datum_gateway_listener_thread(void *arg) {
 		return NULL;
 	}
 
-	ev.events = EPOLLIN;
-	ev.data.fd = listen_sock;
-	if (epoll_ctl(epollfd, EPOLL_CTL_ADD, listen_sock, &ev)<0) {
-		DLOG_FATAL("epoll_ctl failed: %s", strerror(errno));
-		panic_from_thread(__LINE__);
-		return NULL;
+	for (i = 0; i < 2; ++i) {
+		if (listen_socks[i] == -1) continue;
+		ev.events = EPOLLIN;
+		ev.data.fd = listen_socks[i];
+		if (epoll_ctl(epollfd, EPOLL_CTL_ADD, ev.data.fd, &ev) < 0) {
+			DLOG_FATAL("epoll_ctl failed: %s", strerror(errno));
+			panic_from_thread(__LINE__);
+			return NULL;
+		}
 	}
 
 	DLOG_INFO("DATUM Socket listener thread active for '%s'", app->name);
@@ -641,8 +664,8 @@ void *datum_gateway_listener_thread(void *arg) {
 			}
 		}
 		for (int n = 0; n < nfds; ++n) {
-			if (events[n].data.fd == listen_sock) {
-				conn_sock = accept(listen_sock, NULL, NULL);
+			if (events[n].data.fd == listen_socks[0] || events[n].data.fd == listen_socks[1]) {
+				conn_sock = accept(events[n].data.fd, NULL, NULL);
 				if (conn_sock < 0) {
 					DLOG_ERROR("accept failed: %s", strerror(errno));
 					continue;