X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Fmeshlink.c;h=3ebaee01da441aa589279e2ecd4076dd75cc7f1b;hb=11d4da4957cb576abe9ee79c9893809a34f1f3d9;hp=0354c86dc096d5036d6a2298c28dfd5cfbb4fd9e;hpb=4b9b60a5faaa9438ee6c2b4eb67103497ed62a4b;p=meshlink

diff --git a/src/meshlink.c b/src/meshlink.c
index 0354c86d..3ebaee01 100644
--- a/src/meshlink.c
+++ b/src/meshlink.c
@@ -221,12 +221,42 @@ char *meshlink_get_external_address(meshlink_handle_t *mesh) {
 }
 
 char *meshlink_get_external_address_for_family(meshlink_handle_t *mesh, int family) {
-	char *hostname = NULL;
+	const char *url = mesh->external_address_url;
+
+	if(!url) {
+		url = "http://meshlink.io/host.cgi";
+	}
+
+	/* Find the hostname part between the slashes */
+	if(strncmp(url, "http://", 7)) {
+		abort();
+		meshlink_errno = MESHLINK_EINTERNAL;
+		return NULL;
+	}
+
+	const char *begin = url + 7;
+
+	const char *end = strchr(begin, '/');
+
+	if(!end) {
+		end = begin + strlen(begin);
+	}
+
+	/* Make a copy */
+	char host[end - begin + 1];
+	strncpy(host, begin, end - begin);
+	host[end - begin] = 0;
+
+	char *port = strchr(host, ':');
+
+	if(port) {
+		*port++ = 0;
+	}
 
 	logger(mesh, MESHLINK_DEBUG, "Trying to discover externally visible hostname...\n");
-	struct addrinfo *ai = str2addrinfo("meshlink.io", "80", SOCK_STREAM);
-	static const char request[] = "GET http://www.meshlink.io/host.cgi HTTP/1.0\r\n\r\n";
+	struct addrinfo *ai = str2addrinfo(host, port ? port : "80", SOCK_STREAM);
 	char line[256];
+	char *hostname = NULL;
 
 	for(struct addrinfo *aip = ai; aip; aip = aip->ai_next) {
 		if(family != AF_UNSPEC && aip->ai_family != family) {
@@ -245,7 +275,9 @@ char *meshlink_get_external_address_for_family(meshlink_handle_t *mesh, int fami
 		}
 
 		if(s >= 0) {
-			send(s, request, sizeof(request) - 1, 0);
+			send(s, "GET ", 4, 0);
+			send(s, url, strlen(url), 0);
+			send(s, " HTTP/1.0\r\n\r\n", 13, 0);
 			int len = recv(s, line, sizeof(line) - 1, MSG_WAITALL);
 
 			if(len > 0) {
@@ -537,26 +569,52 @@ static bool try_bind(int port) {
 		return false;
 	}
 
-	//while(ai) {
+	bool success = false;
+
 	for(struct addrinfo *aip = ai; aip; aip = aip->ai_next) {
-		int fd = socket(aip->ai_family, SOCK_STREAM, IPPROTO_TCP);
+		/* Try to bind to TCP. */
 
-		if(!fd) {
-			freeaddrinfo(ai);
-			return false;
+		int tcp_fd = socket(aip->ai_family, SOCK_STREAM, IPPROTO_TCP);
+
+		if(tcp_fd == -1) {
+			continue;
 		}
 
-		int result = bind(fd, aip->ai_addr, aip->ai_addrlen);
-		closesocket(fd);
+		int result = bind(tcp_fd, aip->ai_addr, aip->ai_addrlen);
+		closesocket(tcp_fd);
 
 		if(result) {
-			freeaddrinfo(ai);
-			return false;
+			if(errno == EADDRINUSE) {
+				/* If this port is in use for any address family, avoid it. */
+				success = false;
+				break;
+			} else {
+				continue;
+			}
 		}
+
+		/* If TCP worked, then we require that UDP works as well. */
+
+		int udp_fd = socket(aip->ai_family, SOCK_DGRAM, IPPROTO_UDP);
+
+		if(udp_fd == -1) {
+			success = false;
+			break;
+		}
+
+		result = bind(udp_fd, aip->ai_addr, aip->ai_addrlen);
+		closesocket(udp_fd);
+
+		if(result) {
+			success = false;
+			break;
+		}
+
+		success = true;
 	}
 
 	freeaddrinfo(ai);
-	return true;
+	return success;
 }
 
 static int check_port(meshlink_handle_t *mesh) {
@@ -1558,9 +1616,6 @@ static void *meshlink_main_loop(void *arg) {
 }
 
 bool meshlink_start(meshlink_handle_t *mesh) {
-	assert(mesh->self);
-	assert(mesh->private_key);
-
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
@@ -1570,6 +1625,8 @@ bool meshlink_start(meshlink_handle_t *mesh) {
 
 	pthread_mutex_lock(&mesh->mutex);
 
+	assert(mesh->self);
+	assert(mesh->private_key);
 	assert(mesh->self->ecdsa);
 	assert(!memcmp((uint8_t *)mesh->self->ecdsa + 64, (uint8_t *)mesh->private_key + 64, 32));
 
@@ -1729,6 +1786,7 @@ void meshlink_close(meshlink_handle_t *mesh) {
 	free(mesh->appname);
 	free(mesh->confbase);
 	free(mesh->config_key);
+	free(mesh->external_address_url);
 	ecdsa_free(mesh->private_key);
 
 	main_config_unlock(mesh);
@@ -2744,6 +2802,8 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 					state.sock = -1;
 					continue;
 				}
+
+				break;
 			}
 
 			freeaddrinfo(ai);
@@ -3959,6 +4019,23 @@ extern void meshlink_set_inviter_commits_first(struct meshlink_handle *mesh, boo
 	pthread_mutex_unlock(&mesh->mutex);
 }
 
+void meshlink_set_external_address_discovery_url(struct meshlink_handle *mesh, const char *url) {
+	if(!mesh) {
+		meshlink_errno = EINVAL;
+		return;
+	}
+
+	if(url && (strncmp(url, "http://", 7) || strchr(url, ' '))) {
+		meshlink_errno = EINVAL;
+		return;
+	}
+
+	pthread_mutex_lock(&mesh->mutex);
+	free(mesh->external_address_url);
+	mesh->external_address_url = url ? xstrdup(url) : NULL;
+	pthread_mutex_unlock(&mesh->mutex);
+}
+
 void handle_network_change(meshlink_handle_t *mesh, bool online) {
 	(void)online;