X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Fmeshlink.c;h=ef02580ea93d641059eb203c7e3a8a17b14c1ab9;hb=01eaeb3c9fa60ae9c6e5b866acd9baef79622d99;hp=65a82c97f192f65b48fdd6a125c5d7d7c36c42b7;hpb=ba799a101d57c55d4cbf602511aa24c32a5b735e;p=meshlink

diff --git a/src/meshlink.c b/src/meshlink.c
index 65a82c97..ef02580e 100644
--- a/src/meshlink.c
+++ b/src/meshlink.c
@@ -48,8 +48,6 @@ typedef struct {
 #define MSG_NOSIGNAL 0
 #endif
 
-static pthread_mutex_t global_mutex;
-
 __thread meshlink_errno_t meshlink_errno;
 meshlink_log_cb_t global_log_cb;
 meshlink_log_level_t global_log_level;
@@ -503,8 +501,10 @@ static bool finalize_join(meshlink_handle_t *mesh) {
 	}
 
 	char *b64key = ecdsa_get_base64_public_key(mesh->self->connection->ecdsa);
-	if(!b64key)
+	if(!b64key) {
+		fclose(fh);
 		return false;
+		}
 
 	fprintf(fh, "ECDSAPublicKey = %s\n", b64key);
 	fprintf(fh, "Port = %s\n", mesh->myport);
@@ -554,6 +554,7 @@ static bool invitation_receive(void *handle, uint8_t type, const void *msg, uint
 			break;
 
 		case 1:
+			mesh->thedatalen = 0;
 			return finalize_join(mesh);
 
 		case 2:
@@ -742,14 +743,16 @@ static bool meshlink_setup(meshlink_handle_t *mesh) {
 	return true;
 }
 
-meshlink_handle_t *meshlink_open(const char *confbase, const char *name, const char* appname, dclass_t dclass) {
-	return meshlink_open_with_size(confbase, name, appname, dclass, sizeof(meshlink_handle_t));
+meshlink_handle_t *meshlink_open(const char *confbase, const char *name, const char* appname, dev_class_t devclass) {
+	return meshlink_open_with_size(confbase, name, appname, devclass, sizeof(meshlink_handle_t));
 }
 
-meshlink_handle_t *meshlink_open_with_size(const char *confbase, const char *name, const char* appname, dclass_t dclass, size_t size) {
+meshlink_handle_t *meshlink_open_with_size(const char *confbase, const char *name, const char* appname, dev_class_t devclass, size_t size) {
 
 	// Validate arguments provided by the application
 	bool usingname = false;
+	
+	logger(NULL, MESHLINK_DEBUG, "meshlink_open called\n");
 
 	if(!confbase || !*confbase) {
 		logger(NULL, MESHLINK_ERROR, "No confbase given!\n");
@@ -776,12 +779,24 @@ meshlink_handle_t *meshlink_open_with_size(const char *confbase, const char *nam
 		} else { usingname = true;}
 	}
 
+	if(devclass < 0 || devclass > _DEV_CLASS_MAX) {
+		logger(NULL, MESHLINK_ERROR, "Invalid devclass given!\n");
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
+
 	meshlink_handle_t *mesh = xzalloc(size);
 	mesh->confbase = xstrdup(confbase);
 	mesh->appname = xstrdup(appname);
-	mesh->dclass = dclass;
+	mesh->devclass = devclass;
 	if (usingname) mesh->name = xstrdup(name);
-	pthread_mutex_init ( &(mesh->nodes_mutex), NULL);
+
+	// initialize mutex
+	pthread_mutexattr_t attr;
+	pthread_mutexattr_init(&attr);
+	pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
+	pthread_mutex_init(&(mesh->mesh_mutex), &attr);
+	
 	mesh->threadstarted = false;
 	event_loop_init(&mesh->loop);
 	mesh->loop.data = mesh;
@@ -830,29 +845,35 @@ meshlink_handle_t *meshlink_open_with_size(const char *confbase, const char *nam
 		return NULL;
 	}
 
+	logger(NULL, MESHLINK_DEBUG, "meshlink_open returning\n");
 	return mesh;
 }
 
 static void *meshlink_main_loop(void *arg) {
 	meshlink_handle_t *mesh = arg;
 
+	pthread_mutex_lock(&(mesh->mesh_mutex));
+
 	try_outgoing_connections(mesh);
 
 	logger(mesh, MESHLINK_DEBUG, "Starting main_loop...\n");
 	main_loop(mesh);
 	logger(mesh, MESHLINK_DEBUG, "main_loop returned.\n");
 
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	return NULL;
 }
 
 bool meshlink_start(meshlink_handle_t *mesh) {
-
-	logger(mesh, MESHLINK_DEBUG, "meshlink_start called\n");
-
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
+	pthread_mutex_lock(&(mesh->mesh_mutex));
+	
+	logger(mesh, MESHLINK_DEBUG, "meshlink_start called\n");
+
+	mesh->thedatalen = 0;
 
 	// TODO: open listening sockets first
 
@@ -860,6 +881,7 @@ bool meshlink_start(meshlink_handle_t *mesh) {
 	if(!mesh->name ) {
 		logger(mesh, MESHLINK_DEBUG, "No name given!\n");
 		meshlink_errno = MESHLINK_EINVAL;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -869,6 +891,7 @@ bool meshlink_start(meshlink_handle_t *mesh) {
 		logger(mesh, MESHLINK_DEBUG, "Could not start thread: %s\n", strerror(errno));
 		memset(&mesh->thread, 0, sizeof mesh->thread);
 		meshlink_errno = MESHLINK_EINTERNAL;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -876,18 +899,19 @@ bool meshlink_start(meshlink_handle_t *mesh) {
 
 	discovery_start(mesh);
 
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	return true;
 }
 
 void meshlink_stop(meshlink_handle_t *mesh) {
-
-	logger(mesh, MESHLINK_DEBUG, "meshlink_stop called\n");
-	
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
 	}
 
+	pthread_mutex_lock(&(mesh->mesh_mutex));
+	logger(mesh, MESHLINK_DEBUG, "meshlink_stop called\n");
+
 	// Stop discovery
 	discovery_stop(mesh);
 
@@ -897,8 +921,10 @@ void meshlink_stop(meshlink_handle_t *mesh) {
 	shutdown(s->tcp.fd, SHUT_RDWR);
 
 	// Wait for the main thread to finish
-
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	pthread_join(mesh->thread, NULL);
+	pthread_mutex_lock(&(mesh->mesh_mutex));
+
 	mesh->threadstarted = false;
 
 	// Fix the socket
@@ -910,6 +936,8 @@ void meshlink_stop(meshlink_handle_t *mesh) {
 		logger(mesh, MESHLINK_ERROR, "Could not repair listenen socket!");
 	else
 		io_add(&mesh->loop, &s->tcp, handle_new_meta_connection, s, s->tcp.fd, IO_READ);
+	
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 }
 
 void meshlink_close(meshlink_handle_t *mesh) {
@@ -918,6 +946,9 @@ void meshlink_close(meshlink_handle_t *mesh) {
 		return;
 	}
 
+	// lock is not released after this
+	pthread_mutex_lock(&(mesh->mesh_mutex));
+
 	// Close and free all resources used.
 
 	close_network_connections(mesh);
@@ -937,6 +968,7 @@ void meshlink_close(meshlink_handle_t *mesh) {
 	free(mesh->name);
 	free(mesh->appname);
 	free(mesh->confbase);
+	pthread_mutex_destroy(&(mesh->mesh_mutex));
 
 	memset(mesh, 0, sizeof *mesh);
 
@@ -949,7 +981,9 @@ void meshlink_set_receive_cb(meshlink_handle_t *mesh, meshlink_receive_cb_t cb)
 		return;
 	}
 
+	pthread_mutex_lock(&(mesh->mesh_mutex));
 	mesh->receive_cb = cb;
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 }
 
 void meshlink_set_node_status_cb(meshlink_handle_t *mesh, meshlink_node_status_cb_t cb) {
@@ -958,13 +992,17 @@ void meshlink_set_node_status_cb(meshlink_handle_t *mesh, meshlink_node_status_c
 		return;
 	}
 
+	pthread_mutex_lock(&(mesh->mesh_mutex));
 	mesh->node_status_cb = cb;
+	pthread_mutex_unlock(&(mesh->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->mesh_mutex));
 		mesh->log_cb = cb;
 		mesh->log_level = cb ? level : 0;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 	} else {
 		global_log_cb = cb;
 		global_log_level = cb ? level : 0;
@@ -985,6 +1023,8 @@ bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const
 		return false;
 	}
 
+	pthread_mutex_lock(&(mesh->mesh_mutex));
+
 	//add packet to the queue
 	outpacketqueue_t *packet_in_queue = xzalloc(sizeof *packet_in_queue);
 	packet_in_queue->destination=destination;
@@ -992,25 +1032,34 @@ bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const
 	packet_in_queue->len=len;
 	if(!meshlink_queue_push(&mesh->outpacketqueue, packet_in_queue)) {
 		free(packet_in_queue);
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
 	//notify event loop
 	signal_trigger(&(mesh->loop),&(mesh->datafromapp));
+	
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	return true;
 }
 
 void meshlink_send_from_queue(event_loop_t* el,meshlink_handle_t *mesh) {
+	pthread_mutex_lock(&(mesh->mesh_mutex));
+	
 	vpn_packet_t packet;
 	meshlink_packethdr_t *hdr = (meshlink_packethdr_t *)packet.data;
 
 	outpacketqueue_t* p = meshlink_queue_pop(&mesh->outpacketqueue);
 	if(!p)
+	{
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return;
+	}
 
 	if (sizeof(meshlink_packethdr_t) + p->len > MAXSIZE) {
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		//log something
-		return ;
+		return;
 	}
 
 	packet.probe = false;
@@ -1024,6 +1073,8 @@ void meshlink_send_from_queue(event_loop_t* el,meshlink_handle_t *mesh) {
         mesh->self->in_packets++;
         mesh->self->in_bytes += packet.len;
         route(mesh, mesh->self, &packet);
+	
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	return ;
 }
 
@@ -1032,14 +1083,22 @@ ssize_t meshlink_get_pmtu(meshlink_handle_t *mesh, meshlink_node_t *destination)
 		meshlink_errno = MESHLINK_EINVAL;
 		return -1;
 	}
+	pthread_mutex_lock(&(mesh->mesh_mutex));
 
 	node_t *n = (node_t *)destination;
-	if(!n->status.reachable)
+	if(!n->status.reachable) {
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return 0;
-	else if(n->mtuprobes > 30 && n->minmtu)
+	
+	}
+	else if(n->mtuprobes > 30 && n->minmtu) {
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return n->minmtu;
-	else
+	}
+	else {
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return MTU;
+	}
 }
 
 char *meshlink_get_fingerprint(meshlink_handle_t *mesh, meshlink_node_t *node) {
@@ -1047,11 +1106,13 @@ char *meshlink_get_fingerprint(meshlink_handle_t *mesh, meshlink_node_t *node) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return NULL;
 	}
+	pthread_mutex_lock(&(mesh->mesh_mutex));
 
 	node_t *n = (node_t *)node;
 
 	if(!node_read_ecdsa_public_key(mesh, n) || !n->ecdsa) {
 		meshlink_errno = MESHLINK_EINTERNAL;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1060,6 +1121,7 @@ char *meshlink_get_fingerprint(meshlink_handle_t *mesh, meshlink_node_t *node) {
 	if(!fingerprint)
 		meshlink_errno = MESHLINK_EINTERNAL;
 
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	return fingerprint;
 }
 
@@ -1069,7 +1131,12 @@ meshlink_node_t *meshlink_get_node(meshlink_handle_t *mesh, const char *name) {
 		return NULL;
 	}
 
-	return (meshlink_node_t *)lookup_node(mesh, (char *)name); // TODO: make lookup_node() use const
+	meshlink_node_t *node = NULL;
+
+	pthread_mutex_lock(&(mesh->mesh_mutex));
+	node = (meshlink_node_t *)lookup_node(mesh, (char *)name); // TODO: make lookup_node() use const
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
+	return node;
 }
 
 meshlink_node_t **meshlink_get_all_nodes(meshlink_handle_t *mesh, meshlink_node_t **nodes, size_t *nmemb) {
@@ -1081,7 +1148,7 @@ meshlink_node_t **meshlink_get_all_nodes(meshlink_handle_t *mesh, meshlink_node_
 	meshlink_node_t **result;
 
 	//lock mesh->nodes
-	pthread_mutex_lock(&(mesh->nodes_mutex));
+	pthread_mutex_lock(&(mesh->mesh_mutex));
 
 	*nmemb = mesh->nodes->count;
 	result = realloc(nodes, *nmemb * sizeof *nodes);
@@ -1096,7 +1163,7 @@ meshlink_node_t **meshlink_get_all_nodes(meshlink_handle_t *mesh, meshlink_node_
 		meshlink_errno = MESHLINK_ENOMEM;
 	}
 
-	pthread_mutex_unlock(&(mesh->nodes_mutex));
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 
 	return result;
 }
@@ -1112,12 +1179,16 @@ bool meshlink_sign(meshlink_handle_t *mesh, const void *data, size_t len, void *
 		return false;
 	}
 
+	pthread_mutex_lock(&(mesh->mesh_mutex));
+
 	if(!ecdsa_sign(mesh->self->connection->ecdsa, data, len, signature)) {
 		meshlink_errno = MESHLINK_EINTERNAL;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
 	*siglen = MESHLINK_SIGLEN;
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	return true;
 }
 
@@ -1132,23 +1203,32 @@ bool meshlink_verify(meshlink_handle_t *mesh, meshlink_node_t *source, const voi
 		return false;
 	}
 
+	pthread_mutex_lock(&(mesh->mesh_mutex));
+
+	bool rval = false;
+
 	struct node_t *n = (struct node_t *)source;
 	node_read_ecdsa_public_key(mesh, n);
 	if(!n->ecdsa) {
 		meshlink_errno = MESHLINK_EINTERNAL;
-		return false;
+		rval = false;
+	} else {
+		rval = ecdsa_verify(((struct node_t *)source)->ecdsa, data, len, signature);
 	}
-
-	return ecdsa_verify(((struct node_t *)source)->ecdsa, data, len, signature);
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
+	return rval;
 }
 
 static bool refresh_invitation_key(meshlink_handle_t *mesh) {
 	char filename[PATH_MAX];
+	
+	pthread_mutex_lock(&(mesh->mesh_mutex));
 
 	snprintf(filename, sizeof filename, "%s" SLASH "invitations", mesh->confbase);
 	if(mkdir(filename, 0700) && errno != EEXIST) {
 		logger(mesh, MESHLINK_DEBUG, "Could not create directory %s: %s\n", filename, strerror(errno));
 		meshlink_errno = MESHLINK_ESTORAGE;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1157,6 +1237,7 @@ static bool refresh_invitation_key(meshlink_handle_t *mesh) {
 	if(!dir) {
 		logger(mesh, MESHLINK_DEBUG, "Could not read directory %s: %s\n", filename, strerror(errno));
 		meshlink_errno = MESHLINK_ESTORAGE;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1186,6 +1267,7 @@ static bool refresh_invitation_key(meshlink_handle_t *mesh) {
 		logger(mesh, MESHLINK_DEBUG, "Error while reading directory %s: %s\n", filename, strerror(errno));
 		closedir(dir);
 		meshlink_errno = MESHLINK_ESTORAGE;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1202,8 +1284,10 @@ static bool refresh_invitation_key(meshlink_handle_t *mesh) {
 		}
 	}
 
-	if(mesh->invitation_key)
+	if(mesh->invitation_key) {
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return true;
+	}
 
 	// Create a new key if necessary.
 	FILE *f = fopen(filename, "r");
@@ -1211,6 +1295,7 @@ static bool refresh_invitation_key(meshlink_handle_t *mesh) {
 		if(errno != ENOENT) {
 			logger(mesh, MESHLINK_DEBUG, "Could not read %s: %s\n", filename, strerror(errno));
 			meshlink_errno = MESHLINK_ESTORAGE;
+			pthread_mutex_unlock(&(mesh->mesh_mutex));
 			return false;
 		}
 
@@ -1218,12 +1303,14 @@ static bool refresh_invitation_key(meshlink_handle_t *mesh) {
 		if(!mesh->invitation_key) {
 			logger(mesh, MESHLINK_DEBUG, "Could not generate a new key!\n");
 			meshlink_errno = MESHLINK_EINTERNAL;
+			pthread_mutex_unlock(&(mesh->mesh_mutex));
 			return false;
 		}
 		f = fopen(filename, "w");
 		if(!f) {
 			logger(mesh, MESHLINK_DEBUG, "Could not write %s: %s\n", filename, strerror(errno));
 			meshlink_errno = MESHLINK_ESTORAGE;
+			pthread_mutex_unlock(&(mesh->mesh_mutex));
 			return false;
 		}
 		chmod(filename, 0600);
@@ -1238,6 +1325,7 @@ static bool refresh_invitation_key(meshlink_handle_t *mesh) {
 		}
 	}
 
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	return mesh->invitation_key;
 }
 
@@ -1246,16 +1334,23 @@ bool meshlink_add_address(meshlink_handle_t *mesh, const char *address) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
+	
+	bool rval = false;
+
+	pthread_mutex_lock(&(mesh->mesh_mutex));
 
 	for(const char *p = address; *p; p++) {
 		if(isalnum(*p) || *p == '-' || *p == '.' || *p == ':')
 			continue;
 		logger(mesh, MESHLINK_DEBUG, "Invalid character in address: %s\n", address);
 		meshlink_errno = MESHLINK_EINVAL;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
-	return append_config_file(mesh, mesh->self->name, "Address", address);
+	rval = append_config_file(mesh, mesh->self->name, "Address", address);
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
+	return rval;
 }
 
 char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
@@ -1263,11 +1358,14 @@ char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return NULL;
 	}
+	
+	pthread_mutex_lock(&(mesh->mesh_mutex));
 
 	// Check validity of the new node's name
 	if(!check_id(name)) {
 		logger(mesh, MESHLINK_DEBUG, "Invalid name for node.\n");
 		meshlink_errno = MESHLINK_EINVAL;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return NULL;
 	}
 
@@ -1277,6 +1375,7 @@ char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
 	if(!access(filename, F_OK)) {
 		logger(mesh, MESHLINK_DEBUG, "A host config file for %s already exists!\n", name);
 		meshlink_errno = MESHLINK_EEXIST;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return NULL;
 	}
 
@@ -1284,6 +1383,7 @@ char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
 	if(meshlink_get_node(mesh, name)) {
 		logger(mesh, MESHLINK_DEBUG, "A node with name %s is already known!\n", name);
 		meshlink_errno = MESHLINK_EEXIST;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return NULL;
 	}
 
@@ -1292,11 +1392,13 @@ char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
 	if(!address) {
 		logger(mesh, MESHLINK_DEBUG, "No Address known for ourselves!\n");
 		meshlink_errno = MESHLINK_ERESOLV;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return NULL;
 	}
 
 	if(!refresh_invitation_key(mesh)) {
 		meshlink_errno = MESHLINK_EINTERNAL;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return NULL;
 	}
 
@@ -1329,6 +1431,7 @@ char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
 	if(!ifd) {
 		logger(mesh, MESHLINK_DEBUG, "Could not create invitation file %s: %s\n", filename, strerror(errno));
 		meshlink_errno = MESHLINK_ESTORAGE;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return NULL;
 	}
 	FILE *f = fdopen(ifd, "w");
@@ -1359,6 +1462,7 @@ char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
 	} else {
 		logger(mesh, MESHLINK_DEBUG, "Could not create %s: %s\n", filename, strerror(errno));
 		meshlink_errno = MESHLINK_ESTORAGE;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return NULL;
 	}
 
@@ -1374,6 +1478,7 @@ char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
 	xasprintf(&url, "%s/%s%s", address, hash, cookie);
 	free(address);
 
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	return url;
 }
 
@@ -1382,6 +1487,8 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
+	
+	pthread_mutex_lock(&(mesh->mesh_mutex));
 
 	//TODO: think of a better name for this variable, or of a different way to tokenize the invitation URL.
 	char copy[strlen(invitation) + 1];
@@ -1424,6 +1531,7 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 	ecdsa_t *key = ecdsa_generate();
 	if(!key) {
 		meshlink_errno = MESHLINK_EINTERNAL;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1438,6 +1546,7 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 	struct addrinfo *ai = str2addrinfo(address, port, SOCK_STREAM);
 	if(!ai) {
 		meshlink_errno = MESHLINK_ERESOLV;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1446,6 +1555,7 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 		logger(mesh, MESHLINK_DEBUG, "Could not open socket: %s\n", strerror(errno));
 		freeaddrinfo(ai);
 		meshlink_errno = MESHLINK_ENETWORK;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1454,6 +1564,7 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 		closesocket(mesh->sock);
 		freeaddrinfo(ai);
 		meshlink_errno = MESHLINK_ENETWORK;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1469,6 +1580,7 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 		logger(mesh, MESHLINK_DEBUG, "Error sending request to %s port %s: %s\n", address, port, strerror(errno));
 		closesocket(mesh->sock);
 		meshlink_errno = MESHLINK_ENETWORK;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1481,6 +1593,7 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 		logger(mesh, MESHLINK_DEBUG, "Cannot read greeting from peer\n");
 		closesocket(mesh->sock);
 		meshlink_errno = MESHLINK_ENETWORK;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1490,11 +1603,13 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 	if(sha512(fingerprint, strlen(fingerprint), hishash)) {
 		logger(mesh, MESHLINK_DEBUG, "Could not create hash\n%s\n", mesh->line + 2);
 		meshlink_errno = MESHLINK_EINTERNAL;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 	if(memcmp(hishash, mesh->hash, 18)) {
 		logger(mesh, MESHLINK_DEBUG, "Peer has an invalid key!\n%s\n", mesh->line + 2);
 		meshlink_errno = MESHLINK_EPEER;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 
 	}
@@ -1502,18 +1617,21 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 	ecdsa_t *hiskey = ecdsa_set_base64_public_key(fingerprint);
 	if(!hiskey) {
 		meshlink_errno = MESHLINK_EINTERNAL;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
 	// Start an SPTPS session
 	if(!sptps_start(&mesh->sptps, mesh, true, false, key, hiskey, "meshlink invitation", 15, invitation_send, invitation_receive)) {
 		meshlink_errno = MESHLINK_EINTERNAL;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
 	// Feed rest of input buffer to SPTPS
 	if(!sptps_receive_data(&mesh->sptps, mesh->buffer, mesh->blen)) {
 		meshlink_errno = MESHLINK_EPEER;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1525,11 +1643,13 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 				continue;
 			logger(mesh, MESHLINK_DEBUG, "Error reading data from %s port %s: %s\n", address, port, strerror(errno));
 			meshlink_errno = MESHLINK_ENETWORK;
+			pthread_mutex_unlock(&(mesh->mesh_mutex));
 			return false;
 		}
 
 		if(!sptps_receive_data(&mesh->sptps, mesh->line, len)) {
 			meshlink_errno = MESHLINK_EPEER;
+			pthread_mutex_unlock(&(mesh->mesh_mutex));
 			return false;
 		}
 	}
@@ -1542,14 +1662,17 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 	if(!mesh->success) {
 		logger(mesh, MESHLINK_DEBUG, "Connection closed by peer, invitation cancelled.\n");
 		meshlink_errno = MESHLINK_EPEER;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	return true;
 
 invalid:
 	logger(mesh, MESHLINK_DEBUG, "Invalid invitation URL or you are already connected to a Mesh ?\n");
 	meshlink_errno = MESHLINK_EINVAL;
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	return false;
 }
 
@@ -1559,12 +1682,15 @@ char *meshlink_export(meshlink_handle_t *mesh) {
 		return NULL;
 	}
 
+	pthread_mutex_lock(&(mesh->mesh_mutex));
+	
 	char filename[PATH_MAX];
 	snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, mesh->self->name);
 	FILE *f = fopen(filename, "r");
 	if(!f) {
 		logger(mesh, MESHLINK_DEBUG, "Could not open %s: %s\n", filename, strerror(errno));
 		meshlink_errno = MESHLINK_ESTORAGE;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return NULL;
 	}
 
@@ -1579,11 +1705,14 @@ char *meshlink_export(meshlink_handle_t *mesh) {
 		logger(mesh, MESHLINK_DEBUG, "Error reading from %s: %s\n", filename, strerror(errno));
 		fclose(f);
 		meshlink_errno = MESHLINK_ESTORAGE;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return NULL;
 	}
 
 	fclose(f);
 	buf[len - 1] = 0;
+	
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	return buf;
 }
 
@@ -1592,10 +1721,13 @@ bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
+	
+	pthread_mutex_lock(&(mesh->mesh_mutex));
 
 	if(strncmp(data, "Name = ", 7)) {
 		logger(mesh, MESHLINK_DEBUG, "Invalid data\n");
 		meshlink_errno = MESHLINK_EPEER;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1603,6 +1735,7 @@ bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
 	if(!end) {
 		logger(mesh, MESHLINK_DEBUG, "Invalid data\n");
 		meshlink_errno = MESHLINK_EPEER;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1613,6 +1746,7 @@ bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
 	if(!check_id(name)) {
 		logger(mesh, MESHLINK_DEBUG, "Invalid Name\n");
 		meshlink_errno = MESHLINK_EPEER;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1621,12 +1755,14 @@ bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
 	if(!access(filename, F_OK)) {
 		logger(mesh, MESHLINK_DEBUG, "File %s already exists, not importing\n", filename);
 		meshlink_errno = MESHLINK_EEXIST;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
 	if(errno != ENOENT) {
 		logger(mesh, MESHLINK_DEBUG, "Error accessing %s: %s\n", filename, strerror(errno));
 		meshlink_errno = MESHLINK_ESTORAGE;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1634,6 +1770,7 @@ bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
 	if(!f) {
 		logger(mesh, MESHLINK_DEBUG, "Could not create %s: %s\n", filename, strerror(errno));
 		meshlink_errno = MESHLINK_ESTORAGE;
+		pthread_mutex_unlock(&(mesh->mesh_mutex));
 		return false;
 	}
 
@@ -1642,6 +1779,7 @@ bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
 
 	load_all_nodes(mesh);
 
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	return true;
 }
 
@@ -1651,6 +1789,8 @@ void meshlink_blacklist(meshlink_handle_t *mesh, meshlink_node_t *node) {
 		return;
 	}
 
+	pthread_mutex_lock(&(mesh->mesh_mutex));
+	
 	node_t *n;
 	n = (node_t*)node;
 	n->status.blacklisted=true;
@@ -1659,6 +1799,7 @@ void meshlink_blacklist(meshlink_handle_t *mesh, meshlink_node_t *node) {
 	//Make blacklisting persistent in the config file
 	append_config_file(mesh, n->name, "blacklisted", "yes");
 
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	return;
 }
 
@@ -1668,75 +1809,194 @@ void meshlink_whitelist(meshlink_handle_t *mesh, meshlink_node_t *node) {
 		return;
 	}
 
+	pthread_mutex_lock(&(mesh->mesh_mutex));
+	
 	node_t *n = (node_t *)node;
 	n->status.blacklisted = false;
 
 	//TODO: remove blacklisted = yes from the config file
 
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	return;
 }
 
 /* Hint that a hostname may be found at an address
  * See header file for detailed comment.
  */
-extern void meshlink_hint_address(meshlink_handle_t *mesh, meshlink_node_t *node, struct sockaddr *addr) {
+void meshlink_hint_address(meshlink_handle_t *mesh, meshlink_node_t *node, const struct sockaddr *addr) {
 	if(!mesh || !node || !addr)
 		return;
 	
-	char *addr_str = malloc(MAX_ADDRESS_LENGTH*sizeof(char));
-	memset(addr_str, 0, MAX_ADDRESS_LENGTH*sizeof(char));
-
-	char *port_str = malloc(MAX_PORT_LENGTH*sizeof(char));
-	memset(port_str, 0, MAX_PORT_LENGTH*sizeof(char));
+	pthread_mutex_lock(&(mesh->mesh_mutex));
 	
-	// extra byte for a space, and one to make sure string is null-terminated
-	int full_addr_len = MAX_ADDRESS_LENGTH + MAX_PORT_LENGTH + 2;
+	char *host = NULL, *port = NULL, *str = NULL;
+	sockaddr2str((const sockaddr_t *)addr, &host, &port);
 
-	char *full_addr_str = malloc(full_addr_len*sizeof(char));
-	memset(full_addr_str, 0, full_addr_len*sizeof(char));
-	
-	// get address and port number
-	if(!get_ip_str(addr, addr_str, MAX_ADDRESS_LENGTH))
-		goto fail;
-	if(!get_port_str(addr, port_str, MAX_ADDRESS_LENGTH))
-		goto fail;
-
-	// append_config_file expects an address, a space, and then a port number
-	strcat(full_addr_str, addr_str);
-	strcat(full_addr_str, " ");
-	strcat(full_addr_str, port_str);
-	
-	append_config_file(mesh, node->name, "Address", full_addr_str);
+	if(host && port) {
+		xasprintf(&str, "%s %s", host, port);
+		if ( (strncmp ("fe80",host,4) != 0) && ( strncmp("127.",host,4) != 0 ) && ( strcmp("localhost",host) !=0 ) )
+			append_config_file(mesh, node->name, "Address", str);
+		else
+			logger(mesh, MESHLINK_DEBUG, "Not adding Link Local IPv6 Address to config\n");
+	}
 
-fail:
-	free(addr_str);
-	free(port_str);
-	free(full_addr_str);
+	free(str);
+	free(host);
+	free(port);
 
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
 	// @TODO do we want to fire off a connection attempt right away?
 }
 
-static void __attribute__((constructor)) meshlink_init(void) {
-	crypto_init();
+/* Return an array of edges in the current network graph.
+ * Data captures the current state and will not be updated.
+ * Caller must deallocate data when done.
+ */
+meshlink_edge_t **meshlink_get_all_edges_state(meshlink_handle_t *mesh, meshlink_edge_t **edges, size_t *nmemb) {
+	if(!mesh || !nmemb || (*nmemb && !edges)) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
+
+	pthread_mutex_lock(&(mesh->mesh_mutex));
+	
+	meshlink_edge_t **result = NULL;
+	meshlink_edge_t *copy = NULL;
+	int result_size = 0;
+
+	result_size = mesh->edges->count;
+
+	// if result is smaller than edges, we have to dealloc all the excess meshlink_edge_t
+	if(result_size > *nmemb) {
+		result = realloc(edges, result_size * sizeof (meshlink_edge_t*));
+	} else {
+		result = edges;
+	}
+
+	if(result) {
+		meshlink_edge_t **p = result;
+		int n = 0;
+		for splay_each(edge_t, e, mesh->edges) {
+			// skip edges that do not represent a two-directional connection
+			if((!e->reverse) || (e->reverse->to != e->from)) {
+				result_size--;
+				continue;
+			}
+			n++;
+			// the first *nmemb members of result can be re-used
+			if(n > *nmemb) {
+				copy = xzalloc(sizeof *copy);
+			}
+			else {
+				copy = *p;
+			}
+			copy->from = (meshlink_node_t*)e->from;
+			copy->to = (meshlink_node_t*)e->to;
+			copy->address = e->address.storage;
+			copy->options = e->options;
+			copy->weight = e->weight;
+			*p++ = copy;
+		}
+		// shrink result to the actual amount of memory used
+		for(int i = *nmemb; i > result_size; i--) {
+			free(result[i - 1]);
+		}
+		result = realloc(result, result_size * sizeof (meshlink_edge_t*));
+		*nmemb = result_size;
+	} else {
+		*nmemb = 0;
+		free(result);
+		meshlink_errno = MESHLINK_ENOMEM;
+	}
+
+	pthread_mutex_unlock(&(mesh->mesh_mutex));
+
+	return result;
 }
 
-static void __attribute__((destructor)) meshlink_exit(void) {
-	crypto_exit();
+static bool channel_pre_accept(struct utcp *utcp, uint16_t port) {
+	//TODO: implement
+	return false;
 }
 
-int weight_from_dclass(dclass_t dclass)
-{
-	switch(dclass)
-	{
-	case BACKBONE:
-		return 1;
+static void channel_accept(struct utcp_connection *utcp_connection, uint16_t port) {
+	//TODO: implement
+}
 
-	case STATIONARY:
-		return 3;
+static int channel_recv(struct utcp_connection *connection, const void *data, size_t len) {
+	meshlink_channel_t *channel = connection->priv;
+	node_t *n = channel->node;
+	meshlink_handle_t *mesh = n->mesh;
+	if(!channel->receive_cb)
+		return -1;
+	else {
+		channel->receive_cb(mesh, channel, data, len);
+		return 0;
+	}
+}
+
+static int channel_send(struct utcp *utcp, const void *data, size_t len) {
+	node_t *n = utcp->priv;
+	meshlink_handle_t *mesh = n->mesh;
+	return meshlink_send(mesh, (meshlink_node_t *)n, data, len) ? len : -1;
+}
+
+void meshlink_set_channel_accept_cb(meshlink_handle_t *mesh, meshlink_channel_accept_cb_t cb) {
+	mesh->channel_accept_cb = cb;
+}
 
-	case PORTABLE:
-		return 6;
+void meshlink_set_channel_receive_cb(meshlink_handle_t *mesh, meshlink_channel_t *channel, meshlink_channel_receive_cb_t cb) {
+	channel->receive_cb = cb;
+}
+
+meshlink_channel_t *meshlink_channel_open(meshlink_handle_t *mesh, meshlink_node_t *node, uint16_t port, meshlink_channel_receive_cb_t cb, const void *data, size_t len) {
+	node_t *n = (node_t *)node;
+	if(!n->utcp) {
+		n->utcp = utcp_init(channel_accept, channel_pre_accept, channel_send, n);
+		if(!n->utcp)
+			return NULL;
 	}
+	meshlink_channel_t *channel = xzalloc(sizeof *channel);
+	channel->node = n;
+	channel->receive_cb = cb;
+	channel->c = utcp_connect(n->utcp, port, channel_recv, channel);
+	if(!channel->c) {
+		free(channel);
+		return NULL;
+	}
+	return channel;
+}
 
-	return 9;
+void meshlink_channel_shutdown(meshlink_handle_t *mesh, meshlink_channel_t *channel, int direction) {
+	utcp_shutdown(channel->c, direction);
 }
+
+void meshlink_channel_close(meshlink_handle_t *mesh, meshlink_channel_t *channel) {
+	utcp_close(channel->c);
+	free(channel);
+}
+
+ssize_t meshlink_channel_send(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len) {
+	// TODO: locking.
+	// Ideally we want to put the data into the UTCP connection's send buffer.
+	// Then, preferrably only if there is room in the receiver window,
+	// kick the meshlink thread to go send packets.
+	return utcp_send(channel->c, data, len);
+}
+
+static void __attribute__((constructor)) meshlink_init(void) {
+	crypto_init();
+}
+
+static void __attribute__((destructor)) meshlink_exit(void) {
+	crypto_exit();
+}
+
+
+/// Device class traits
+dev_class_traits_t dev_class_traits[_DEV_CLASS_MAX +1] = {
+	{ .min_connects = 3, .max_connects = 10000, .edge_weight = 1 },	// DEV_CLASS_BACKBONE
+	{ .min_connects = 3, .max_connects = 100, .edge_weight = 3 },	// DEV_CLASS_STATIONARY
+	{ .min_connects = 3, .max_connects = 3, .edge_weight = 6 },		// DEV_CLASS_PORTABLE
+	{ .min_connects = 1, .max_connects = 1, .edge_weight = 9 },		// DEV_CLASS_UNKNOWN
+};