X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Fmeshlink.c;h=4f9c5f407ba93b6680faa8aef5c8c3d6c0a10ede;hb=001cbb9549f17153536ee6a01a783eb85bf54962;hp=cdf9b17dcd94fe1d77d31a4102b539cf4049f02e;hpb=f342cb44b25cd61eed17897575015be4aae1dd17;p=meshlink

diff --git a/src/meshlink.c b/src/meshlink.c
index cdf9b17d..4f9c5f40 100644
--- a/src/meshlink.c
+++ b/src/meshlink.c
@@ -154,7 +154,9 @@ static int socket_in_netns(int domain, int type, int protocol, int netns) {
 	pthread_t thr;
 
 	if(pthread_create(&thr, NULL, socket_in_netns_thread, &params) == 0) {
-		pthread_join(thr, NULL);
+		if(pthread_join(thr, NULL) != 0) {
+			abort();
+		}
 	}
 
 	return params.fd;
@@ -167,7 +169,7 @@ static int socket_in_netns(int domain, int type, int protocol, int netns) {
 // Find out what local address a socket would use if we connect to the given address.
 // We do this using connect() on a UDP socket, so the kernel has to resolve the address
 // of both endpoints, but this will actually not send any UDP packet.
-static bool getlocaladdr(char *destaddr, sockaddr_t *sa, socklen_t *salen, int netns) {
+static bool getlocaladdr(const char *destaddr, sockaddr_t *sa, socklen_t *salen, int netns) {
 	struct addrinfo *rai = NULL;
 	const struct addrinfo hint = {
 		.ai_family = AF_UNSPEC,
@@ -204,7 +206,7 @@ static bool getlocaladdr(char *destaddr, sockaddr_t *sa, socklen_t *salen, int n
 	return true;
 }
 
-static bool getlocaladdrname(char *destaddr, char *host, socklen_t hostlen, int netns) {
+static bool getlocaladdrname(const char *destaddr, char *host, socklen_t hostlen, int netns) {
 	sockaddr_t sa;
 	socklen_t salen = sizeof(sa);
 
@@ -257,7 +259,7 @@ char *meshlink_get_external_address_for_family(meshlink_handle_t *mesh, int fami
 	}
 
 	logger(mesh, MESHLINK_DEBUG, "Trying to discover externally visible hostname...\n");
-	struct addrinfo *ai = adns_blocking_request(mesh, xstrdup(host), xstrdup(port ? port : "80"), 5);
+	struct addrinfo *ai = adns_blocking_request(mesh, xstrdup(host), xstrdup(port ? port : "80"), SOCK_STREAM, 5);
 	char line[256];
 	char *hostname = NULL;
 
@@ -268,6 +270,11 @@ char *meshlink_get_external_address_for_family(meshlink_handle_t *mesh, int fami
 
 		int s = socket_in_netns(aip->ai_family, aip->ai_socktype, aip->ai_protocol, mesh->netns);
 
+#ifdef SO_NOSIGPIPE
+		int nosigpipe = 1;
+		setsockopt(s, SOL_SOCKET, SO_NOSIGPIPE, &nosigpipe, sizeof(nosigpipe));
+#endif
+
 		if(s >= 0) {
 			set_timeout(s, 5000);
 
@@ -337,6 +344,52 @@ static bool is_localaddr(sockaddr_t *sa) {
 	}
 }
 
+#ifdef HAVE_GETIFADDRS
+struct getifaddrs_in_netns_params {
+	struct ifaddrs **ifa;
+	int netns;
+};
+
+#ifdef HAVE_SETNS
+static void *getifaddrs_in_netns_thread(void *arg) {
+	struct getifaddrs_in_netns_params *params = arg;
+
+	if(setns(params->netns, CLONE_NEWNET) == -1) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
+
+	if(getifaddrs(params->ifa) != 0) {
+		*params->ifa = NULL;
+	}
+
+	return NULL;
+}
+#endif // HAVE_SETNS
+
+static int getifaddrs_in_netns(struct ifaddrs **ifa, int netns) {
+	if(netns == -1) {
+		return getifaddrs(ifa);
+	}
+
+#ifdef HAVE_SETNS
+	struct getifaddrs_in_netns_params params = {ifa, netns};
+	pthread_t thr;
+
+	if(pthread_create(&thr, NULL, getifaddrs_in_netns_thread, &params) == 0) {
+		if(pthread_join(thr, NULL) != 0) {
+			abort();
+		}
+	}
+
+	return *params.ifa ? 0 : -1;
+#else
+	return -1;
+#endif // HAVE_SETNS
+
+}
+#endif
+
 char *meshlink_get_local_address_for_family(meshlink_handle_t *mesh, int family) {
 	(void)mesh;
 
@@ -354,12 +407,12 @@ char *meshlink_get_local_address_for_family(meshlink_handle_t *mesh, int family)
 
 	if(!success) {
 		struct ifaddrs *ifa = NULL;
-		getifaddrs(&ifa);
+		getifaddrs_in_netns(&ifa, mesh->netns);
 
 		for(struct ifaddrs *ifap = ifa; ifap; ifap = ifap->ifa_next) {
 			sockaddr_t *sa = (sockaddr_t *)ifap->ifa_addr;
 
-			if(sa->sa.sa_family != family) {
+			if(!sa || sa->sa.sa_family != family) {
 				continue;
 			}
 
@@ -386,7 +439,7 @@ char *meshlink_get_local_address_for_family(meshlink_handle_t *mesh, int family)
 	return xstrdup(localaddr);
 }
 
-void remove_duplicate_hostnames(char *host[], char *port[], int n) {
+static void remove_duplicate_hostnames(char *host[], char *port[], int n) {
 	for(int i = 0; i < n; i++) {
 		if(!host[i]) {
 			continue;
@@ -501,7 +554,7 @@ static char *get_my_hostname(meshlink_handle_t *mesh, uint32_t flags) {
 		}
 
 		// Convert what we have to a sockaddr
-		struct addrinfo *ai_in = adns_blocking_request(mesh, xstrdup(hostname[i]), xstrdup(port[i]), 5);
+		struct addrinfo *ai_in = adns_blocking_request(mesh, xstrdup(hostname[i]), xstrdup(port[i]), SOCK_STREAM, 5);
 
 		if(!ai_in) {
 			continue;
@@ -665,24 +718,28 @@ static bool finalize_join(join_state_t *state, const void *buf, uint16_t len) {
 	}
 
 	char *name = packmsg_get_str_dup(&in);
-	packmsg_skip_element(&in); /* submesh */
+	char *submesh_name = packmsg_get_str_dup(&in);
 	dev_class_t devclass = packmsg_get_int32(&in);
 	uint32_t count = packmsg_get_array(&in);
 
-	if(!name) {
-		logger(mesh, MESHLINK_DEBUG, "No Name found in invitation!\n");
+	if(!name || !check_id(name)) {
+		logger(mesh, MESHLINK_DEBUG, "No valid Name found in invitation!\n");
+		free(name);
+		free(submesh_name);
 		return false;
 	}
 
-	if(!check_id(name)) {
-		logger(mesh, MESHLINK_DEBUG, "Invalid Name found in invitation: %s!\n", name);
+	if(!submesh_name || (strcmp(submesh_name, CORE_MESH) && !check_id(submesh_name))) {
+		logger(mesh, MESHLINK_DEBUG, "No valid Submesh found in invitation!\n");
 		free(name);
+		free(submesh_name);
 		return false;
 	}
 
 	if(!count) {
 		logger(mesh, MESHLINK_ERROR, "Incomplete invitation file!\n");
 		free(name);
+		free(submesh_name);
 		return false;
 	}
 
@@ -690,6 +747,8 @@ static bool finalize_join(join_state_t *state, const void *buf, uint16_t len) {
 	free(mesh->self->name);
 	mesh->name = name;
 	mesh->self->name = xstrdup(name);
+	mesh->self->submesh = strcmp(submesh_name, CORE_MESH) ? lookup_or_create_submesh(mesh, submesh_name) : NULL;
+	free(submesh_name);
 	mesh->self->devclass = devclass == DEV_CLASS_UNKNOWN ? mesh->devclass : devclass;
 
 	// Initialize configuration directory
@@ -704,39 +763,39 @@ static bool finalize_join(join_state_t *state, const void *buf, uint16_t len) {
 	// Write host config files
 	for(uint32_t i = 0; i < count; i++) {
 		const void *data;
-		uint32_t len = packmsg_get_bin_raw(&in, &data);
+		uint32_t data_len = packmsg_get_bin_raw(&in, &data);
 
-		if(!len) {
+		if(!data_len) {
 			logger(mesh, MESHLINK_ERROR, "Incomplete invitation file!\n");
 			return false;
 		}
 
-		packmsg_input_t in2 = {data, len};
-		uint32_t version = packmsg_get_uint32(&in2);
-		char *name = packmsg_get_str_dup(&in2);
+		packmsg_input_t in2 = {data, data_len};
+		uint32_t version2 = packmsg_get_uint32(&in2);
+		char *name2 = packmsg_get_str_dup(&in2);
 
-		if(!packmsg_input_ok(&in2) || version != MESHLINK_CONFIG_VERSION || !check_id(name)) {
-			free(name);
+		if(!packmsg_input_ok(&in2) || version2 != MESHLINK_CONFIG_VERSION || !check_id(name2)) {
+			free(name2);
 			packmsg_input_invalidate(&in);
 			break;
 		}
 
-		if(!check_id(name)) {
-			free(name);
+		if(!check_id(name2)) {
+			free(name2);
 			break;
 		}
 
-		if(!strcmp(name, mesh->name)) {
+		if(!strcmp(name2, mesh->name)) {
 			logger(mesh, MESHLINK_DEBUG, "Secondary chunk would overwrite our own host config file.\n");
-			free(name);
+			free(name2);
 			meshlink_errno = MESHLINK_EPEER;
 			return false;
 		}
 
 		node_t *n = new_node();
-		n->name = name;
+		n->name = name2;
 
-		config_t config = {data, len};
+		config_t config = {data, data_len};
 
 		if(!node_read_from_config(mesh, n, &config)) {
 			free_node(n);
@@ -770,7 +829,7 @@ static bool finalize_join(join_state_t *state, const void *buf, uint16_t len) {
 	}
 
 	/* Ensure the configuration directory metadata is on disk */
-	if(!config_sync(mesh, "current") || !sync_path(mesh->confbase)) {
+	if(!config_sync(mesh, "current") || (mesh->confbase && !sync_path(mesh->confbase))) {
 		return false;
 	}
 
@@ -882,7 +941,7 @@ static bool recvline(join_state_t *state) {
 	return true;
 }
 
-static bool sendline(int fd, char *format, ...) {
+static bool sendline(int fd, const char *format, ...) {
 	char buffer[4096];
 	char *p = buffer;
 	int blen = 0;
@@ -1083,9 +1142,6 @@ static bool meshlink_read_config(meshlink_handle_t *mesh) {
 		return false;
 	}
 
-#if 0
-
-	// TODO: check this?
 	if(mesh->name && strcmp(mesh->name, name)) {
 		logger(NULL, MESHLINK_ERROR, "Configuration is for a different name (%s)!", name);
 		meshlink_errno = MESHLINK_ESTORAGE;
@@ -1094,8 +1150,6 @@ static bool meshlink_read_config(meshlink_handle_t *mesh) {
 		return false;
 	}
 
-#endif
-
 	free(mesh->name);
 	mesh->name = name;
 	xasprintf(&mesh->myport, "%u", myport);
@@ -1153,13 +1207,7 @@ meshlink_open_params_t *meshlink_open_params_init(const char *confbase, const ch
 		return NULL;
 	}
 
-	if(!name || !*name) {
-		logger(NULL, MESHLINK_ERROR, "No name given!\n");
-		meshlink_errno = MESHLINK_EINVAL;
-		return NULL;
-	};
-
-	if(!check_id(name)) {
+	if(name && !check_id(name)) {
 		logger(NULL, MESHLINK_ERROR, "Invalid name given!\n");
 		meshlink_errno = MESHLINK_EINVAL;
 		return NULL;
@@ -1174,7 +1222,7 @@ meshlink_open_params_t *meshlink_open_params_init(const char *confbase, const ch
 	meshlink_open_params_t *params = xzalloc(sizeof * params);
 
 	params->confbase = xstrdup(confbase);
-	params->name = xstrdup(name);
+	params->name = name ? xstrdup(name) : NULL;
 	params->appname = xstrdup(appname);
 	params->devclass = devclass;
 	params->netns = -1;
@@ -1218,7 +1266,9 @@ bool meshlink_encrypted_key_rotate(meshlink_handle_t *mesh, const void *new_key,
 		return false;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	// Create hash for the new key
 	void *new_config_key;
@@ -1296,10 +1346,10 @@ void meshlink_open_params_free(meshlink_open_params_t *params) {
 
 /// Device class traits
 static const dev_class_traits_t default_class_traits[DEV_CLASS_COUNT] = {
-	{ .pingtimeout = 5, .pinginterval = 60, .min_connects = 3, .max_connects = 10000, .edge_weight = 1 }, // DEV_CLASS_BACKBONE
-	{ .pingtimeout = 5, .pinginterval = 60, .min_connects = 3, .max_connects = 100, .edge_weight = 3 },   // DEV_CLASS_STATIONARY
-	{ .pingtimeout = 5, .pinginterval = 60, .min_connects = 3, .max_connects = 3, .edge_weight = 6 },     // DEV_CLASS_PORTABLE
-	{ .pingtimeout = 5, .pinginterval = 60, .min_connects = 1, .max_connects = 1, .edge_weight = 9 },     // DEV_CLASS_UNKNOWN
+	{ .pingtimeout = 5, .pinginterval = 60, .maxtimeout = 900, .min_connects = 3, .max_connects = 10000, .edge_weight = 1 }, // DEV_CLASS_BACKBONE
+	{ .pingtimeout = 5, .pinginterval = 60, .maxtimeout = 900, .min_connects = 3, .max_connects = 100, .edge_weight = 3 },   // DEV_CLASS_STATIONARY
+	{ .pingtimeout = 5, .pinginterval = 60, .maxtimeout = 900, .min_connects = 3, .max_connects = 3, .edge_weight = 6 },     // DEV_CLASS_PORTABLE
+	{ .pingtimeout = 5, .pinginterval = 60, .maxtimeout = 900, .min_connects = 1, .max_connects = 1, .edge_weight = 9 },     // DEV_CLASS_UNKNOWN
 };
 
 meshlink_handle_t *meshlink_open(const char *confbase, const char *name, const char *appname, dev_class_t devclass) {
@@ -1347,6 +1397,36 @@ meshlink_handle_t *meshlink_open_encrypted(const char *confbase, const char *nam
 }
 
 meshlink_handle_t *meshlink_open_ephemeral(const char *name, const char *appname, dev_class_t devclass) {
+	if(!name) {
+		logger(NULL, MESHLINK_ERROR, "No name given!\n");
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
+
+	if(!check_id(name)) {
+		logger(NULL, MESHLINK_ERROR, "Invalid name given!\n");
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
+
+	if(!appname || !*appname) {
+		logger(NULL, MESHLINK_ERROR, "No appname given!\n");
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
+
+	if(strchr(appname, ' ')) {
+		logger(NULL, MESHLINK_ERROR, "Invalid appname given!\n");
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
+
+	if(devclass < 0 || devclass >= DEV_CLASS_COUNT) {
+		logger(NULL, MESHLINK_ERROR, "Invalid devclass given!\n");
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
+
 	/* Create a temporary struct on the stack, to avoid allocating and freeing one. */
 	meshlink_open_params_t params;
 	memset(&params, 0, sizeof(params));
@@ -1360,11 +1440,9 @@ meshlink_handle_t *meshlink_open_ephemeral(const char *name, const char *appname
 }
 
 meshlink_handle_t *meshlink_open_ex(const meshlink_open_params_t *params) {
-	// Validate arguments provided by the application
-	bool usingname = false;
-
 	logger(NULL, MESHLINK_DEBUG, "meshlink_open called\n");
 
+	// Validate arguments provided by the application
 	if(!params->appname || !*params->appname) {
 		logger(NULL, MESHLINK_ERROR, "No appname given!\n");
 		meshlink_errno = MESHLINK_EINVAL;
@@ -1377,18 +1455,10 @@ meshlink_handle_t *meshlink_open_ex(const meshlink_open_params_t *params) {
 		return NULL;
 	}
 
-	if(!params->name || !*params->name) {
-		logger(NULL, MESHLINK_ERROR, "No name given!\n");
-		//return NULL;
-	} else { //check name only if there is a name != NULL
-
-		if(!check_id(params->name)) {
-			logger(NULL, MESHLINK_ERROR, "Invalid name given!\n");
-			meshlink_errno = MESHLINK_EINVAL;
-			return NULL;
-		} else {
-			usingname = true;
-		}
+	if(params->name && !check_id(params->name)) {
+		logger(NULL, MESHLINK_ERROR, "Invalid name given!\n");
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
 	}
 
 	if(params->devclass < 0 || params->devclass >= DEV_CLASS_COUNT) {
@@ -1427,9 +1497,7 @@ meshlink_handle_t *meshlink_open_ex(const meshlink_open_params_t *params) {
 
 	memcpy(mesh->dev_class_traits, default_class_traits, sizeof(default_class_traits));
 
-	if(usingname) {
-		mesh->name = xstrdup(params->name);
-	}
+	mesh->name = params->name ? xstrdup(params->name) : NULL;
 
 	// Hash the key
 	if(params->key) {
@@ -1443,11 +1511,21 @@ meshlink_handle_t *meshlink_open_ex(const meshlink_open_params_t *params) {
 		}
 	}
 
-	// initialize mutex
+	// initialize mutexes and conds
 	pthread_mutexattr_t attr;
 	pthread_mutexattr_init(&attr);
-	pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
+
+	if(pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE) != 0) {
+		abort();
+	}
+
 	pthread_mutex_init(&mesh->mutex, &attr);
+	pthread_cond_init(&mesh->cond, NULL);
+
+	pthread_mutex_init(&mesh->discovery_mutex, NULL);
+	pthread_cond_init(&mesh->discovery_cond, NULL);
+
+	pthread_cond_init(&mesh->adns_cond, NULL);
 
 	mesh->threadstarted = false;
 	event_loop_init(&mesh->loop);
@@ -1464,6 +1542,13 @@ meshlink_handle_t *meshlink_open_ex(const meshlink_open_params_t *params) {
 	// If no configuration exists yet, create it.
 
 	if(!meshlink_confbase_exists(mesh)) {
+		if(!mesh->name) {
+			logger(NULL, MESHLINK_ERROR, "No configuration files found!\n");
+			meshlink_close(mesh);
+			meshlink_errno = MESHLINK_ESTORAGE;
+			return NULL;
+		}
+
 		if(!meshlink_setup(mesh)) {
 			logger(NULL, MESHLINK_ERROR, "Cannot create initial configuration\n");
 			meshlink_close(mesh);
@@ -1540,7 +1625,9 @@ meshlink_submesh_t *meshlink_submesh_open(meshlink_handle_t  *mesh, const char *
 	}
 
 	//lock mesh->nodes
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	s = (meshlink_submesh_t *)create_submesh(mesh, submesh);
 
@@ -1574,7 +1661,9 @@ static void *meshlink_main_loop(void *arg) {
 
 #endif
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	logger(mesh, MESHLINK_DEBUG, "Starting main_loop...\n");
 	pthread_cond_broadcast(&mesh->cond);
@@ -1603,7 +1692,9 @@ bool meshlink_start(meshlink_handle_t *mesh) {
 
 	logger(mesh, MESHLINK_DEBUG, "meshlink_start called\n");
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	assert(mesh->self);
 	assert(mesh->private_key);
@@ -1622,6 +1713,11 @@ bool meshlink_start(meshlink_handle_t *mesh) {
 		return false;
 	}
 
+	// Reset node connection timers
+	for splay_each(node_t, n, mesh->nodes) {
+		n->last_connect_try = 0;
+	}
+
 	// TODO: open listening sockets first
 
 	//Check that a valid name is set
@@ -1639,7 +1735,12 @@ bool meshlink_start(meshlink_handle_t *mesh) {
 
 	event_loop_start(&mesh->loop);
 
-	if(pthread_create(&mesh->thread, NULL, meshlink_main_loop, mesh) != 0) {
+	// Ensure we have a decent amount of stack space. Musl's default of 80 kB is too small.
+	pthread_attr_t attr;
+	pthread_attr_init(&attr);
+	pthread_attr_setstacksize(&attr, 1024 * 1024);
+
+	if(pthread_create(&mesh->thread, &attr, meshlink_main_loop, mesh) != 0) {
 		logger(mesh, MESHLINK_DEBUG, "Could not start thread: %s\n", strerror(errno));
 		memset(&mesh->thread, 0, sizeof(mesh)->thread);
 		meshlink_errno = MESHLINK_EINTERNAL;
@@ -1664,7 +1765,10 @@ void meshlink_stop(meshlink_handle_t *mesh) {
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	logger(mesh, MESHLINK_DEBUG, "meshlink_stop called\n");
 
 	// Shut down the main thread
@@ -1688,8 +1792,14 @@ void meshlink_stop(meshlink_handle_t *mesh) {
 	if(mesh->threadstarted) {
 		// Wait for the main thread to finish
 		pthread_mutex_unlock(&mesh->mutex);
-		pthread_join(mesh->thread, NULL);
-		pthread_mutex_lock(&mesh->mutex);
+
+		if(pthread_join(mesh->thread, NULL) != 0) {
+			abort();
+		}
+
+		if(pthread_mutex_lock(&mesh->mutex) != 0) {
+			abort();
+		}
 
 		mesh->threadstarted = false;
 	}
@@ -1734,7 +1844,9 @@ void meshlink_close(meshlink_handle_t *mesh) {
 	meshlink_stop(mesh);
 
 	// lock is not released after this
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	// Close and free all resources used.
 
@@ -1855,7 +1967,10 @@ void meshlink_set_receive_cb(meshlink_handle_t *mesh, meshlink_receive_cb_t cb)
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	mesh->receive_cb = cb;
 	pthread_mutex_unlock(&mesh->mutex);
 }
@@ -1866,7 +1981,10 @@ void meshlink_set_connection_try_cb(meshlink_handle_t *mesh, meshlink_connection
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	mesh->connection_try_cb = cb;
 	pthread_mutex_unlock(&mesh->mutex);
 }
@@ -1877,7 +1995,10 @@ void meshlink_set_node_status_cb(meshlink_handle_t *mesh, meshlink_node_status_c
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	mesh->node_status_cb = cb;
 	pthread_mutex_unlock(&mesh->mutex);
 }
@@ -1888,7 +2009,10 @@ void meshlink_set_node_pmtu_cb(meshlink_handle_t *mesh, meshlink_node_pmtu_cb_t
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	mesh->node_pmtu_cb = cb;
 	pthread_mutex_unlock(&mesh->mutex);
 }
@@ -1899,14 +2023,20 @@ void meshlink_set_node_duplicate_cb(meshlink_handle_t *mesh, meshlink_node_dupli
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	mesh->node_duplicate_cb = cb;
 	pthread_mutex_unlock(&mesh->mutex);
 }
 
 void meshlink_set_log_cb(meshlink_handle_t *mesh, meshlink_log_level_t level, meshlink_log_cb_t cb) {
 	if(mesh) {
-		pthread_mutex_lock(&mesh->mutex);
+		if(pthread_mutex_lock(&mesh->mutex) != 0) {
+			abort();
+		}
+
 		mesh->log_cb = cb;
 		mesh->log_level = cb ? level : 0;
 		pthread_mutex_unlock(&mesh->mutex);
@@ -1922,7 +2052,10 @@ void meshlink_set_error_cb(struct meshlink_handle *mesh, meshlink_error_cb_t cb)
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	mesh->error_cb = cb;
 	pthread_mutex_unlock(&mesh->mutex);
 }
@@ -1930,7 +2063,7 @@ void meshlink_set_error_cb(struct meshlink_handle *mesh, meshlink_error_cb_t cb)
 static bool prepare_packet(meshlink_handle_t *mesh, meshlink_node_t *destination, const void *data, size_t len, vpn_packet_t *packet) {
 	meshlink_packethdr_t *hdr;
 
-	if(len >= MAXSIZE - sizeof(*hdr)) {
+	if(len > MAXSIZE - sizeof(*hdr)) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
@@ -1952,8 +2085,8 @@ static bool prepare_packet(meshlink_handle_t *mesh, meshlink_node_t *destination
 	memset(hdr, 0, sizeof(*hdr));
 	// leave the last byte as 0 to make sure strings are always
 	// null-terminated if they are longer than the buffer
-	strncpy((char *)hdr->destination, destination->name, (sizeof(hdr)->destination) - 1);
-	strncpy((char *)hdr->source, mesh->self->name, (sizeof(hdr)->source) - 1);
+	strncpy((char *)hdr->destination, destination->name, sizeof(hdr->destination) - 1);
+	strncpy((char *)hdr->source, mesh->self->name, sizeof(hdr->source) - 1);
 
 	memcpy(packet->data + sizeof(*hdr), data, len);
 
@@ -2003,6 +2136,7 @@ bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const
 
 	if(!prepare_packet(mesh, destination, data, len, packet)) {
 		free(packet);
+		return false;
 	}
 
 	// Queue it
@@ -2041,7 +2175,9 @@ ssize_t meshlink_get_pmtu(meshlink_handle_t *mesh, meshlink_node_t *destination)
 		return -1;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	node_t *n = (node_t *)destination;
 
@@ -2064,7 +2200,9 @@ char *meshlink_get_fingerprint(meshlink_handle_t *mesh, meshlink_node_t *node) {
 		return NULL;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	node_t *n = (node_t *)node;
 
@@ -2101,7 +2239,10 @@ meshlink_node_t *meshlink_get_node(meshlink_handle_t *mesh, const char *name) {
 
 	node_t *n = NULL;
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	n = lookup_node(mesh, (char *)name); // TODO: make lookup_node() use const
 	pthread_mutex_unlock(&mesh->mutex);
 
@@ -2120,7 +2261,10 @@ meshlink_submesh_t *meshlink_get_submesh(meshlink_handle_t *mesh, const char *na
 
 	meshlink_submesh_t *submesh = NULL;
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	submesh = (meshlink_submesh_t *)lookup_submesh(mesh, name);
 	pthread_mutex_unlock(&mesh->mutex);
 
@@ -2140,7 +2284,9 @@ meshlink_node_t **meshlink_get_all_nodes(meshlink_handle_t *mesh, meshlink_node_
 	meshlink_node_t **result;
 
 	//lock mesh->nodes
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	*nmemb = mesh->nodes->count;
 	result = realloc(nodes, *nmemb * sizeof(*nodes));
@@ -2165,7 +2311,9 @@ meshlink_node_t **meshlink_get_all_nodes(meshlink_handle_t *mesh, meshlink_node_
 static meshlink_node_t **meshlink_get_all_nodes_by_condition(meshlink_handle_t *mesh, const void *condition, meshlink_node_t **nodes, size_t *nmemb, search_node_by_condition_t search_node) {
 	meshlink_node_t **result;
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	*nmemb = 0;
 
@@ -2212,6 +2360,10 @@ static bool search_node_by_dev_class(const node_t *node, const void *condition)
 	return false;
 }
 
+static bool search_node_by_blacklisted(const node_t *node, const void *condition) {
+	return *(bool *)condition == node->status.blacklisted;
+}
+
 static bool search_node_by_submesh(const node_t *node, const void *condition) {
 	if(condition == node->submesh) {
 		return true;
@@ -2274,6 +2426,15 @@ meshlink_node_t **meshlink_get_all_nodes_by_last_reachable(meshlink_handle_t *me
 	return meshlink_get_all_nodes_by_condition(mesh, &range, nodes, nmemb, search_node_by_last_reachable);
 }
 
+meshlink_node_t **meshlink_get_all_nodes_by_blacklisted(meshlink_handle_t *mesh, bool blacklisted, meshlink_node_t **nodes, size_t *nmemb) {
+	if(!mesh || !nmemb) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
+
+	return meshlink_get_all_nodes_by_condition(mesh, &blacklisted, nodes, nmemb, search_node_by_blacklisted);
+}
+
 dev_class_t meshlink_get_node_dev_class(meshlink_handle_t *mesh, meshlink_node_t *node) {
 	if(!mesh || !node) {
 		meshlink_errno = MESHLINK_EINVAL;
@@ -2282,7 +2443,9 @@ dev_class_t meshlink_get_node_dev_class(meshlink_handle_t *mesh, meshlink_node_t
 
 	dev_class_t devclass;
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	devclass = ((node_t *)node)->devclass;
 
@@ -2291,6 +2454,28 @@ dev_class_t meshlink_get_node_dev_class(meshlink_handle_t *mesh, meshlink_node_t
 	return devclass;
 }
 
+bool meshlink_get_node_blacklisted(meshlink_handle_t *mesh, meshlink_node_t *node) {
+	if(!mesh) {
+		meshlink_errno = MESHLINK_EINVAL;
+	}
+
+	if(!node) {
+		return mesh->default_blacklist;
+	}
+
+	bool blacklisted;
+
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
+	blacklisted = ((node_t *)node)->status.blacklisted;
+
+	pthread_mutex_unlock(&mesh->mutex);
+
+	return blacklisted;
+}
+
 meshlink_submesh_t *meshlink_get_node_submesh(meshlink_handle_t *mesh, meshlink_node_t *node) {
 	if(!mesh || !node) {
 		meshlink_errno = MESHLINK_EINVAL;
@@ -2315,7 +2500,10 @@ bool meshlink_get_node_reachability(struct meshlink_handle *mesh, struct meshlin
 	node_t *n = (node_t *)node;
 	bool reachable;
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	reachable = n->status.reachable && !n->status.blacklisted;
 
 	if(last_reachable) {
@@ -2342,7 +2530,9 @@ bool meshlink_sign(meshlink_handle_t *mesh, const void *data, size_t len, void *
 		return false;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	if(!ecdsa_sign(mesh->private_key, data, len, signature)) {
 		meshlink_errno = MESHLINK_EINTERNAL;
@@ -2366,7 +2556,9 @@ bool meshlink_verify(meshlink_handle_t *mesh, meshlink_node_t *source, const voi
 		return false;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	bool rval = false;
 
@@ -2384,7 +2576,9 @@ bool meshlink_verify(meshlink_handle_t *mesh, meshlink_node_t *source, const voi
 }
 
 static bool refresh_invitation_key(meshlink_handle_t *mesh) {
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	size_t count = invitation_purge_old(mesh, time(NULL) - mesh->invitation_timeout);
 
@@ -2404,26 +2598,31 @@ bool meshlink_set_canonical_address(meshlink_handle_t *mesh, meshlink_node_t *no
 	}
 
 	if(!is_valid_hostname(address)) {
-		logger(mesh, MESHLINK_DEBUG, "Invalid character in address: %s\n", address);
+		logger(mesh, MESHLINK_DEBUG, "Invalid character in address: %s", address);
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
+	if((node_t *)node != mesh->self && !port) {
+		logger(mesh, MESHLINK_DEBUG, "Missing port number!");
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
+
 	}
 
 	if(port && !is_valid_port(port)) {
-		logger(mesh, MESHLINK_DEBUG, "Invalid character in port: %s\n", address);
+		logger(mesh, MESHLINK_DEBUG, "Invalid character in port: %s", address);
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
 
 	char *canonical_address;
 
-	if(port) {
-		xasprintf(&canonical_address, "%s %s", address, port);
-	} else {
-		canonical_address = xstrdup(address);
-	}
+	xasprintf(&canonical_address, "%s %s", address, port ? port : mesh->myport);
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	node_t *n = (node_t *)node;
 	free(n->canonical_address);
@@ -2439,6 +2638,30 @@ bool meshlink_set_canonical_address(meshlink_handle_t *mesh, meshlink_node_t *no
 	return config_sync(mesh, "current");
 }
 
+bool meshlink_clear_canonical_address(meshlink_handle_t *mesh, meshlink_node_t *node) {
+	if(!mesh || !node) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
+	node_t *n = (node_t *)node;
+	free(n->canonical_address);
+	n->canonical_address = NULL;
+
+	if(!node_write_config(mesh, n)) {
+		pthread_mutex_unlock(&mesh->mutex);
+		return false;
+	}
+
+	pthread_mutex_unlock(&mesh->mutex);
+
+	return config_sync(mesh, "current");
+}
+
 bool meshlink_add_invitation_address(struct meshlink_handle *mesh, const char *address, const char *port) {
 	if(!mesh || !address) {
 		meshlink_errno = MESHLINK_EINVAL;
@@ -2465,7 +2688,9 @@ bool meshlink_add_invitation_address(struct meshlink_handle *mesh, const char *a
 		combo = xstrdup(address);
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	if(!mesh->invitation_addresses) {
 		mesh->invitation_addresses = list_alloc((list_action_t)free);
@@ -2483,7 +2708,9 @@ void meshlink_clear_invitation_addresses(struct meshlink_handle *mesh) {
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	if(mesh->invitation_addresses) {
 		list_delete_list(mesh->invitation_addresses);
@@ -2528,7 +2755,10 @@ int meshlink_get_port(meshlink_handle_t *mesh) {
 
 	int port;
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	port = atoi(mesh->myport);
 	pthread_mutex_unlock(&mesh->mutex);
 
@@ -2554,7 +2784,9 @@ bool meshlink_set_port(meshlink_handle_t *mesh, int port) {
 
 	bool rval = false;
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	if(mesh->threadstarted) {
 		meshlink_errno = MESHLINK_EINVAL;
@@ -2624,7 +2856,9 @@ char *meshlink_invite_ex(meshlink_handle_t *mesh, meshlink_submesh_t *submesh, c
 		s = (meshlink_submesh_t *)mesh->self->submesh;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	// Check validity of the new node's name
 	if(!check_id(name)) {
@@ -2766,7 +3000,9 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 	//TODO: think of a better name for this variable, or of a different way to tokenize the invitation URL.
 	char copy[strlen(invitation) + 1];
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	//Before doing meshlink_join make sure we are not connected to another mesh
 	if(mesh->threadstarted) {
@@ -2854,11 +3090,11 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 		}
 
 		// Connect to the meshlink daemon mentioned in the URL.
-		struct addrinfo *ai = adns_blocking_request(mesh, xstrdup(address), xstrdup(port), 5);
+		struct addrinfo *ai = adns_blocking_request(mesh, xstrdup(address), xstrdup(port), SOCK_STREAM, 5);
 
 		if(ai) {
 			for(struct addrinfo *aip = ai; aip; aip = aip->ai_next) {
-				state.sock = socket_in_netns(aip->ai_family, aip->ai_socktype, aip->ai_protocol, mesh->netns);
+				state.sock = socket_in_netns(aip->ai_family, SOCK_STREAM, IPPROTO_TCP, mesh->netns);
 
 				if(state.sock == -1) {
 					logger(mesh, MESHLINK_DEBUG, "Could not open socket: %s\n", strerror(errno));
@@ -2866,6 +3102,11 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 					continue;
 				}
 
+#ifdef SO_NOSIGPIPE
+				int nosigpipe = 1;
+				setsockopt(state.sock, SOL_SOCKET, SO_NOSIGPIPE, &nosigpipe, sizeof(nosigpipe));
+#endif
+
 				set_timeout(state.sock, 5000);
 
 				if(connect(state.sock, aip->ai_addr, aip->ai_addrlen)) {
@@ -3017,12 +3258,22 @@ char *meshlink_export(meshlink_handle_t *mesh) {
 	packmsg_add_str(&out, mesh->name);
 	packmsg_add_str(&out, CORE_MESH);
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	packmsg_add_int32(&out, mesh->self->devclass);
 	packmsg_add_bool(&out, mesh->self->status.blacklisted);
 	packmsg_add_bin(&out, ecdsa_get_public_key(mesh->private_key), 32);
-	packmsg_add_str(&out, mesh->self->canonical_address ? mesh->self->canonical_address : "");
+
+	if(mesh->self->canonical_address && !strchr(mesh->self->canonical_address, ' ')) {
+		char *canonical_address = NULL;
+		xasprintf(&canonical_address, "%s %s", mesh->self->canonical_address, mesh->myport);
+		packmsg_add_str(&out, canonical_address);
+		free(canonical_address);
+	} else {
+		packmsg_add_str(&out, mesh->self->canonical_address ? mesh->self->canonical_address : "");
+	}
 
 	uint32_t count = 0;
 
@@ -3097,17 +3348,19 @@ bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
 		return false;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	while(count--) {
-		const void *data;
-		uint32_t len = packmsg_get_bin_raw(&in, &data);
+		const void *data2;
+		uint32_t len2 = packmsg_get_bin_raw(&in, &data2);
 
-		if(!len) {
+		if(!len2) {
 			break;
 		}
 
-		packmsg_input_t in2 = {data, len};
+		packmsg_input_t in2 = {data2, len2};
 		uint32_t version = packmsg_get_uint32(&in2);
 		char *name = packmsg_get_str_dup(&in2);
 
@@ -3133,7 +3386,7 @@ bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
 		n = new_node();
 		n->name = name;
 
-		config_t config = {data, len};
+		config_t config = {data2, len2};
 
 		if(!node_read_from_config(mesh, n, &config)) {
 			free_node(n);
@@ -3212,6 +3465,9 @@ static bool blacklist(meshlink_handle_t *mesh, node_t *n) {
 		mesh->node_status_cb(mesh, (meshlink_node_t *)n, false);
 	}
 
+	/* Remove any outstanding invitations */
+	invitation_purge_node(mesh, n->name);
+
 	return node_write_config(mesh, n) && config_sync(mesh, "current");
 }
 
@@ -3221,7 +3477,9 @@ bool meshlink_blacklist(meshlink_handle_t *mesh, meshlink_node_t *node) {
 		return false;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	if(!blacklist(mesh, (node_t *)node)) {
 		pthread_mutex_unlock(&mesh->mutex);
@@ -3240,7 +3498,9 @@ bool meshlink_blacklist_by_name(meshlink_handle_t *mesh, const char *name) {
 		return false;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	node_t *n = lookup_node(mesh, (char *)name);
 
@@ -3289,7 +3549,9 @@ bool meshlink_whitelist(meshlink_handle_t *mesh, meshlink_node_t *node) {
 		return false;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	if(!whitelist(mesh, (node_t *)node)) {
 		pthread_mutex_unlock(&mesh->mutex);
@@ -3308,7 +3570,9 @@ bool meshlink_whitelist_by_name(meshlink_handle_t *mesh, const char *name) {
 		return false;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	node_t *n = lookup_node(mesh, (char *)name);
 
@@ -3341,7 +3605,9 @@ bool meshlink_forget_node(meshlink_handle_t *mesh, meshlink_node_t *node) {
 
 	node_t *n = (node_t *)node;
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	/* Check that the node is not reachable */
 	if(n->status.reachable || n->connection) {
@@ -3370,7 +3636,7 @@ bool meshlink_forget_node(meshlink_handle_t *mesh, meshlink_node_t *node) {
 	if(mesh->outgoings) {
 		for list_each(outgoing_t, outgoing, mesh->outgoings) {
 			if(outgoing->node == n) {
-				list_delete_node(mesh->outgoings, node);
+				list_delete_node(mesh->outgoings, list_node);
 			}
 		}
 	}
@@ -3381,6 +3647,9 @@ bool meshlink_forget_node(meshlink_handle_t *mesh, meshlink_node_t *node) {
 		return false;
 	}
 
+	/* Delete any pending invitations */
+	invitation_purge_node(mesh, n->name);
+
 	/* Delete the node struct and any remaining edges referencing this node */
 	node_del(mesh, n);
 
@@ -3398,7 +3667,9 @@ void meshlink_hint_address(meshlink_handle_t *mesh, meshlink_node_t *node, const
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	node_t *n = (node_t *)node;
 
@@ -3416,19 +3687,54 @@ static bool channel_pre_accept(struct utcp *utcp, uint16_t port) {
 	(void)port;
 	node_t *n = utcp->priv;
 	meshlink_handle_t *mesh = n->mesh;
-	return mesh->channel_accept_cb;
+
+	if(mesh->channel_accept_cb && mesh->channel_listen_cb) {
+		return mesh->channel_listen_cb(mesh, (meshlink_node_t *)n, port);
+	} else {
+		return mesh->channel_accept_cb;
+	}
 }
 
-static void aio_signal(meshlink_handle_t *mesh, meshlink_channel_t *channel, meshlink_aio_buffer_t *aio) {
-	if(aio->data) {
-		if(aio->cb.buffer) {
-			aio->cb.buffer(mesh, channel, aio->data, aio->len, aio->priv);
+/* Finish one AIO buffer, return true if the channel is still open. */
+static bool aio_finish_one(meshlink_handle_t *mesh, meshlink_channel_t *channel, meshlink_aio_buffer_t **head) {
+	meshlink_aio_buffer_t *aio = *head;
+	*head = aio->next;
+
+	if(channel->c) {
+		channel->in_callback = true;
+
+		if(aio->data) {
+			if(aio->cb.buffer) {
+				aio->cb.buffer(mesh, channel, aio->data, aio->done, aio->priv);
+			}
+		} else {
+			if(aio->cb.fd) {
+				aio->cb.fd(mesh, channel, aio->fd, aio->done, aio->priv);
+			}
+		}
+
+		channel->in_callback = false;
+
+		if(!channel->c) {
+			free(aio);
+			free(channel);
+			return false;
 		}
-	} else {
-		if(aio->cb.fd) {
-			aio->cb.fd(mesh, channel, aio->fd, aio->done, aio->priv);
+	}
+
+	free(aio);
+	return true;
+}
+
+/* Finish all AIO buffers, return true if the channel is still open. */
+static bool aio_abort(meshlink_handle_t *mesh, meshlink_channel_t *channel, meshlink_aio_buffer_t **head) {
+	while(*head) {
+		if(!aio_finish_one(mesh, channel, head)) {
+			return false;
 		}
 	}
+
+	return true;
 }
 
 static ssize_t channel_recv(struct utcp_connection *connection, const void *data, size_t len) {
@@ -3450,6 +3756,15 @@ static ssize_t channel_recv(struct utcp_connection *connection, const void *data
 	size_t left = len;
 
 	while(channel->aio_receive) {
+		if(!len) {
+			/* This receive callback signalled an error, abort all outstanding AIO buffers. */
+			if(!aio_abort(mesh, channel, &channel->aio_receive)) {
+				return len;
+			}
+
+			break;
+		}
+
 		meshlink_aio_buffer_t *aio = channel->aio_receive;
 		size_t todo = aio->len - aio->done;
 
@@ -3462,23 +3777,35 @@ static ssize_t channel_recv(struct utcp_connection *connection, const void *data
 		} else {
 			ssize_t result = write(aio->fd, p, todo);
 
-			if(result > 0) {
-				todo = result;
+			if(result <= 0) {
+				if(result < 0 && errno == EINTR) {
+					continue;
+				}
+
+				/* Writing to fd failed, cancel just this AIO buffer. */
+				logger(mesh, MESHLINK_ERROR, "Writing to AIO fd %d failed: %s", aio->fd, strerror(errno));
+
+				if(!aio_finish_one(mesh, channel, &channel->aio_receive)) {
+					return len;
+				}
+
+				continue;
 			}
+
+			todo = result;
 		}
 
 		aio->done += todo;
+		p += todo;
+		left -= todo;
 
 		if(aio->done == aio->len) {
-			channel->aio_receive = aio->next;
-			aio_signal(mesh, channel, aio);
-			free(aio);
+			if(!aio_finish_one(mesh, channel, &channel->aio_receive)) {
+				return len;
+			}
 		}
 
-		p += todo;
-		left -= todo;
-
-		if(!left && len) {
+		if(!left) {
 			return len;
 		}
 	}
@@ -3514,6 +3841,17 @@ static void channel_accept(struct utcp_connection *utcp_connection, uint16_t por
 	}
 }
 
+static void channel_retransmit(struct utcp_connection *utcp_connection) {
+	node_t *n = utcp_connection->utcp->priv;
+	meshlink_handle_t *mesh = n->mesh;
+
+	if(n->mtuprobes == 31) {
+		timeout_set(&mesh->loop, &n->mtutimeout, &(struct timespec) {
+			0, 0
+		});
+	}
+}
+
 static ssize_t channel_send(struct utcp *utcp, const void *data, size_t len) {
 	node_t *n = utcp->priv;
 
@@ -3554,56 +3892,90 @@ static void channel_poll(struct utcp_connection *connection, size_t len) {
 
 	node_t *n = channel->node;
 	meshlink_handle_t *mesh = n->mesh;
-	meshlink_aio_buffer_t *aio = channel->aio_send;
 
-	if(aio) {
-		/* We at least one AIO buffer. Send as much as possible form the first buffer. */
-		size_t left = aio->len - aio->done;
+	while(channel->aio_send) {
+		if(!len) {
+			/* This poll callback signalled an error, abort all outstanding AIO buffers. */
+			if(!aio_abort(mesh, channel, &channel->aio_send)) {
+				return;
+			}
+
+			break;
+		}
+
+		/* We have at least one AIO buffer. Send as much as possible from the buffers. */
+		meshlink_aio_buffer_t *aio = channel->aio_send;
+		size_t todo = aio->len - aio->done;
 		ssize_t sent;
 
-		if(len > left) {
-			len = left;
+		if(todo > len) {
+			todo = len;
 		}
 
 		if(aio->data) {
-			sent = utcp_send(connection, (char *)aio->data + aio->done, len);
+			sent = utcp_send(connection, (char *)aio->data + aio->done, todo);
 		} else {
-			char buf[65536];
-			size_t todo = utcp_get_sndbuf_free(connection);
-
-			if(todo > left) {
-				todo = left;
-			}
-
-			if(todo > sizeof(buf)) {
-				todo = sizeof(buf);
+			/* Limit the amount we read at once to avoid stack overflows */
+			if(todo > 65536) {
+				todo = 65536;
 			}
 
+			char buf[todo];
 			ssize_t result = read(aio->fd, buf, todo);
 
 			if(result > 0) {
-				sent = utcp_send(connection, buf, result);
+				todo = result;
+				sent = utcp_send(connection, buf, todo);
 			} else {
-				sent = result;
+				if(result < 0 && errno == EINTR) {
+					continue;
+				}
+
+				/* Reading from fd failed, cancel just this AIO buffer. */
+				if(result != 0) {
+					logger(mesh, MESHLINK_ERROR, "Reading from AIO fd %d failed: %s", aio->fd, strerror(errno));
+				}
+
+				if(!aio_finish_one(mesh, channel, &channel->aio_send)) {
+					return;
+				}
+
+				continue;
 			}
 		}
 
-		if(sent >= 0) {
-			aio->done += sent;
+		if(sent != (ssize_t)todo) {
+			/* Sending failed, abort all outstanding AIO buffers and send a poll callback. */
+			if(!aio_abort(mesh, channel, &channel->aio_send)) {
+				return;
+			}
+
+			len = 0;
+			break;
 		}
 
-		/* If the buffer is now completely sent, call the callback and dispose of it. */
-		if(aio->done >= aio->len) {
-			channel->aio_send = aio->next;
-			aio_signal(mesh, channel, aio);
-			free(aio);
+		aio->done += sent;
+		len -= sent;
+
+		/* If we didn't finish this buffer, exit early. */
+		if(aio->done < aio->len) {
+			return;
 		}
-	} else {
-		if(channel->poll_cb) {
-			channel->poll_cb(mesh, channel, len);
-		} else {
-			utcp_set_poll_cb(connection, NULL);
+
+		/* Signal completion of this buffer, and go to the next one. */
+		if(!aio_finish_one(mesh, channel, &channel->aio_send)) {
+			return;
 		}
+
+		if(!len) {
+			return;
+		}
+	}
+
+	if(channel->poll_cb) {
+		channel->poll_cb(mesh, channel, len);
+	} else {
+		utcp_set_poll_cb(connection, NULL);
 	}
 }
 
@@ -3613,19 +3985,40 @@ void meshlink_set_channel_poll_cb(meshlink_handle_t *mesh, meshlink_channel_t *c
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	channel->poll_cb = cb;
 	utcp_set_poll_cb(channel->c, (cb || channel->aio_send) ? channel_poll : NULL);
 	pthread_mutex_unlock(&mesh->mutex);
 }
 
+void meshlink_set_channel_listen_cb(meshlink_handle_t *mesh, meshlink_channel_listen_cb_t cb) {
+	if(!mesh) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return;
+	}
+
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
+	mesh->channel_listen_cb = cb;
+
+	pthread_mutex_unlock(&mesh->mutex);
+}
+
 void meshlink_set_channel_accept_cb(meshlink_handle_t *mesh, meshlink_channel_accept_cb_t cb) {
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	mesh->channel_accept_cb = cb;
 	mesh->receive_cb = channel_receive;
 
@@ -3633,6 +4026,7 @@ void meshlink_set_channel_accept_cb(meshlink_handle_t *mesh, meshlink_channel_ac
 		if(!n->utcp && n != mesh->self) {
 			n->utcp = utcp_init(channel_accept, channel_pre_accept, channel_send, n);
 			utcp_set_mtu(n->utcp, n->mtu - sizeof(meshlink_packethdr_t));
+			utcp_set_retransmit_cb(n->utcp, channel_retransmit);
 		}
 	}
 
@@ -3647,7 +4041,10 @@ void meshlink_set_channel_sndbuf(meshlink_handle_t *mesh, meshlink_channel_t *ch
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	utcp_set_sndbuf(channel->c, size);
 	pthread_mutex_unlock(&mesh->mutex);
 }
@@ -3660,7 +4057,10 @@ void meshlink_set_channel_rcvbuf(meshlink_handle_t *mesh, meshlink_channel_t *ch
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	utcp_set_rcvbuf(channel->c, size);
 	pthread_mutex_unlock(&mesh->mutex);
 }
@@ -3675,13 +4075,16 @@ meshlink_channel_t *meshlink_channel_open_ex(meshlink_handle_t *mesh, meshlink_n
 		return NULL;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	node_t *n = (node_t *)node;
 
 	if(!n->utcp) {
 		n->utcp = utcp_init(channel_accept, channel_pre_accept, channel_send, n);
 		utcp_set_mtu(n->utcp, n->mtu - sizeof(meshlink_packethdr_t));
+		utcp_set_retransmit_cb(n->utcp, channel_retransmit);
 		mesh->receive_cb = channel_receive;
 
 		if(!n->utcp) {
@@ -3729,7 +4132,10 @@ void meshlink_channel_shutdown(meshlink_handle_t *mesh, meshlink_channel_t *chan
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	utcp_shutdown(channel->c, direction);
 	pthread_mutex_unlock(&mesh->mutex);
 }
@@ -3740,26 +4146,24 @@ void meshlink_channel_close(meshlink_handle_t *mesh, meshlink_channel_t *channel
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
-	utcp_close(channel->c);
+	if(channel->c) {
+		utcp_close(channel->c);
+		channel->c = NULL;
 
-	/* Clean up any outstanding AIO buffers. */
-	for(meshlink_aio_buffer_t *aio = channel->aio_send, *next; aio; aio = next) {
-		next = aio->next;
-		aio_signal(mesh, channel, aio);
-		free(aio);
+		/* Clean up any outstanding AIO buffers. */
+		aio_abort(mesh, channel, &channel->aio_send);
+		aio_abort(mesh, channel, &channel->aio_receive);
 	}
 
-	for(meshlink_aio_buffer_t *aio = channel->aio_receive, *next; aio; aio = next) {
-		next = aio->next;
-		aio_signal(mesh, channel, aio);
-		free(aio);
+	if(!channel->in_callback) {
+		free(channel);
 	}
 
 	pthread_mutex_unlock(&mesh->mutex);
-
-	free(channel);
 }
 
 ssize_t meshlink_channel_send(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len) {
@@ -3784,7 +4188,9 @@ ssize_t meshlink_channel_send(meshlink_handle_t *mesh, meshlink_channel_t *chann
 
 	ssize_t retval;
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	/* Disallow direct calls to utcp_send() while we still have AIO active. */
 	if(channel->aio_send) {
@@ -3819,7 +4225,9 @@ bool meshlink_channel_aio_send(meshlink_handle_t *mesh, meshlink_channel_t *chan
 	aio->cb.buffer = cb;
 	aio->priv = priv;
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	/* Append the AIO buffer descriptor to the end of the chain */
 	meshlink_aio_buffer_t **p = &channel->aio_send;
@@ -3832,7 +4240,11 @@ bool meshlink_channel_aio_send(meshlink_handle_t *mesh, meshlink_channel_t *chan
 
 	/* Ensure the poll callback is set, and call it right now to push data if possible */
 	utcp_set_poll_cb(channel->c, channel_poll);
-	channel_poll(channel->c, len);
+	size_t todo = MIN(len, utcp_get_rcvbuf_free(channel->c));
+
+	if(todo) {
+		channel_poll(channel->c, todo);
+	}
 
 	pthread_mutex_unlock(&mesh->mutex);
 
@@ -3856,7 +4268,9 @@ bool meshlink_channel_aio_fd_send(meshlink_handle_t *mesh, meshlink_channel_t *c
 	aio->cb.fd = cb;
 	aio->priv = priv;
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	/* Append the AIO buffer descriptor to the end of the chain */
 	meshlink_aio_buffer_t **p = &channel->aio_send;
@@ -3869,7 +4283,11 @@ bool meshlink_channel_aio_fd_send(meshlink_handle_t *mesh, meshlink_channel_t *c
 
 	/* Ensure the poll callback is set, and call it right now to push data if possible */
 	utcp_set_poll_cb(channel->c, channel_poll);
-	channel_poll(channel->c, len);
+	size_t left = utcp_get_rcvbuf_free(channel->c);
+
+	if(left) {
+		channel_poll(channel->c, left);
+	}
 
 	pthread_mutex_unlock(&mesh->mutex);
 
@@ -3893,7 +4311,9 @@ bool meshlink_channel_aio_receive(meshlink_handle_t *mesh, meshlink_channel_t *c
 	aio->cb.buffer = cb;
 	aio->priv = priv;
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	/* Append the AIO buffer descriptor to the end of the chain */
 	meshlink_aio_buffer_t **p = &channel->aio_receive;
@@ -3926,7 +4346,9 @@ bool meshlink_channel_aio_fd_receive(meshlink_handle_t *mesh, meshlink_channel_t
 	aio->cb.fd = cb;
 	aio->priv = priv;
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	/* Append the AIO buffer descriptor to the end of the chain */
 	meshlink_aio_buffer_t **p = &channel->aio_receive;
@@ -3986,11 +4408,14 @@ void meshlink_set_node_channel_timeout(meshlink_handle_t *mesh, meshlink_node_t
 
 	node_t *n = (node_t *)node;
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	if(!n->utcp) {
 		n->utcp = utcp_init(channel_accept, channel_pre_accept, channel_send, n);
 		utcp_set_mtu(n->utcp, n->mtu - sizeof(meshlink_packethdr_t));
+		utcp_set_retransmit_cb(n->utcp, channel_retransmit);
 	}
 
 	utcp_set_user_timeout(n->utcp, timeout);
@@ -4002,6 +4427,7 @@ void update_node_status(meshlink_handle_t *mesh, node_t *n) {
 	if(n->status.reachable && mesh->channel_accept_cb && !n->utcp) {
 		n->utcp = utcp_init(channel_accept, channel_pre_accept, channel_send, n);
 		utcp_set_mtu(n->utcp, n->mtu - sizeof(meshlink_packethdr_t));
+		utcp_set_retransmit_cb(n->utcp, channel_retransmit);
 	}
 
 	if(mesh->node_status_cb) {
@@ -4038,7 +4464,9 @@ void meshlink_enable_discovery(meshlink_handle_t *mesh, bool enable) {
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	if(mesh->discovery == enable) {
 		goto end;
@@ -4074,7 +4502,10 @@ void meshlink_set_dev_class_timeouts(meshlink_handle_t *mesh, dev_class_t devcla
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	mesh->dev_class_traits[devclass].pinginterval = pinginterval;
 	mesh->dev_class_traits[devclass].pingtimeout = pingtimeout;
 	pthread_mutex_unlock(&mesh->mutex);
@@ -4091,18 +4522,56 @@ void meshlink_set_dev_class_fast_retry_period(meshlink_handle_t *mesh, dev_class
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	mesh->dev_class_traits[devclass].fast_retry_period = fast_retry_period;
 	pthread_mutex_unlock(&mesh->mutex);
 }
 
-extern void meshlink_set_inviter_commits_first(struct meshlink_handle *mesh, bool inviter_commits_first) {
+void meshlink_set_dev_class_maxtimeout(struct meshlink_handle *mesh, dev_class_t devclass, int maxtimeout) {
+	if(!mesh || devclass < 0 || devclass >= DEV_CLASS_COUNT) {
+		meshlink_errno = EINVAL;
+		return;
+	}
+
+	if(maxtimeout < 0) {
+		meshlink_errno = EINVAL;
+		return;
+	}
+
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
+	mesh->dev_class_traits[devclass].maxtimeout = maxtimeout;
+	pthread_mutex_unlock(&mesh->mutex);
+}
+
+void meshlink_reset_timers(struct meshlink_handle *mesh) {
+	if(!mesh) {
+		return;
+	}
+
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
+	handle_network_change(mesh, true);
+	pthread_mutex_unlock(&mesh->mutex);
+}
+
+void meshlink_set_inviter_commits_first(struct meshlink_handle *mesh, bool inviter_commits_first) {
 	if(!mesh) {
 		meshlink_errno = EINVAL;
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	mesh->inviter_commits_first = inviter_commits_first;
 	pthread_mutex_unlock(&mesh->mutex);
 }
@@ -4118,7 +4587,10 @@ void meshlink_set_external_address_discovery_url(struct meshlink_handle *mesh, c
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	free(mesh->external_address_url);
 	mesh->external_address_url = url ? xstrdup(url) : NULL;
 	pthread_mutex_unlock(&mesh->mutex);
@@ -4141,9 +4613,10 @@ void handle_network_change(meshlink_handle_t *mesh, bool online) {
 	}
 
 	retry(mesh);
+	signal_trigger(&mesh->loop, &mesh->datafromapp);
 }
 
-void call_error_cb(meshlink_handle_t *mesh, meshlink_errno_t meshlink_errno) {
+void call_error_cb(meshlink_handle_t *mesh, meshlink_errno_t cb_errno) {
 	// We should only call the callback function if we are in the background thread.
 	if(!mesh->error_cb) {
 		return;
@@ -4154,7 +4627,7 @@ void call_error_cb(meshlink_handle_t *mesh, meshlink_errno_t meshlink_errno) {
 	}
 
 	if(mesh->thread == pthread_self()) {
-		mesh->error_cb(mesh, meshlink_errno);
+		mesh->error_cb(mesh, cb_errno);
 	}
 }