X-Git-Url: http://git.meshlink.io/?p=meshlink;a=blobdiff_plain;f=src%2Fmeshlink.c;h=a1a2ec407c87477a9e77e204b700b5f944afdb52;hp=6e7cda60a3f71fd1a94424c754af48a1288ae0c5;hb=HEAD;hpb=32d723c40d6fa959779f35973411185a320529d1

diff --git a/src/meshlink.c b/src/meshlink.c
index 6e7cda60..a1a2ec40 100644
--- a/src/meshlink.c
+++ b/src/meshlink.c
@@ -1,6 +1,6 @@
 /*
     meshlink.c -- Implementation of the MeshLink API.
-    Copyright (C) 2014-2018 Guus Sliepen <guus@meshlink.io>
+    Copyright (C) 2014-2021 Guus Sliepen <guus@meshlink.io>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -20,10 +20,12 @@
 #include "system.h"
 #include <pthread.h>
 
+#include "adns.h"
 #include "crypto.h"
 #include "ecdsagen.h"
 #include "logger.h"
 #include "meshlink_internal.h"
+#include "net.h"
 #include "netutl.h"
 #include "node.h"
 #include "submesh.h"
@@ -152,7 +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;
@@ -165,12 +169,13 @@ 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,
 		.ai_socktype = SOCK_DGRAM,
 		.ai_protocol = IPPROTO_UDP,
+		.ai_flags = AI_NUMERICHOST | AI_NUMERICSERV,
 	};
 
 	if(getaddrinfo(destaddr, "80", &hint, &rai) || !rai) {
@@ -201,7 +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);
 
@@ -221,6 +226,7 @@ char *meshlink_get_external_address(meshlink_handle_t *mesh) {
 }
 
 char *meshlink_get_external_address_for_family(meshlink_handle_t *mesh, int family) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_get_external_address_for_family(%d)", family);
 	const char *url = mesh->external_address_url;
 
 	if(!url) {
@@ -254,7 +260,7 @@ 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 = str2addrinfo(host, port ? port : "80", SOCK_STREAM);
+	struct addrinfo *ai = adns_blocking_request(mesh, xstrdup(host), xstrdup(port ? port : "80"), SOCK_STREAM, 5);
 	char line[256];
 	char *hostname = NULL;
 
@@ -265,6 +271,11 @@ 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);
 
@@ -334,8 +345,59 @@ 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;
+	logger(mesh, MESHLINK_DEBUG, "meshlink_get_local_address_for_family(%d)", family);
+
+	if(!mesh) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
 
 	// Determine address of the local interface used for outgoing connections.
 	char localaddr[NI_MAXHOST];
@@ -351,12 +413,12 @@ 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;
 			}
 
@@ -383,7 +445,7 @@ 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;
@@ -442,11 +504,11 @@ static char *get_my_hostname(meshlink_handle_t *mesh, uint32_t flags) {
 	if(mesh->invitation_addresses) {
 		for list_each(char, combo, mesh->invitation_addresses) {
 			hostname[n] = xstrdup(combo);
-			char *colon = strchr(hostname[n], ':');
+			char *slash = strrchr(hostname[n], '/');
 
-			if(colon) {
-				*colon = 0;
-				port[n] = xstrdup(colon + 1);
+			if(slash) {
+				*slash = 0;
+				port[n] = xstrdup(slash + 1);
 			}
 
 			n++;
@@ -482,82 +544,42 @@ static char *get_my_hostname(meshlink_handle_t *mesh, uint32_t flags) {
 		}
 	}
 
-	for(int i = 0; i < 4; i++) {
+	for(int i = 0; i < n; i++) {
 		// Ensure we always have a port number
 		if(hostname[i] && !port[i]) {
 			port[i] = xstrdup(mesh->myport);
 		}
 	}
 
-	remove_duplicate_hostnames(hostname, port, 4);
+	remove_duplicate_hostnames(hostname, port, n);
 
 	// Resolve the hostnames
-	for(int i = 0; i < 4; i++) {
+	for(int i = 0; i < n; i++) {
 		if(!hostname[i]) {
 			continue;
 		}
 
 		// Convert what we have to a sockaddr
-		struct addrinfo *ai_in, *ai_out;
-		struct addrinfo hint = {
-			.ai_family = AF_UNSPEC,
-			.ai_flags = AI_NUMERICSERV,
-			.ai_socktype = SOCK_STREAM,
-		};
-		int err = getaddrinfo(hostname[i], port[i], &hint, &ai_in);
-
-		if(err || !ai_in) {
-			continue;
-		}
-
-		// Remember the address
-		node_add_recent_address(mesh, mesh->self, (sockaddr_t *)ai_in->ai_addr);
-
-		if(flags & MESHLINK_INVITE_NUMERIC) {
-			// We don't need to do any further conversion
-			freeaddrinfo(ai_in);
-			continue;
-		}
-
-		// Convert it to a hostname
-		char resolved_host[NI_MAXHOST];
-		char resolved_port[NI_MAXSERV];
-		err = getnameinfo(ai_in->ai_addr, ai_in->ai_addrlen, resolved_host, sizeof resolved_host, resolved_port, sizeof resolved_port, NI_NUMERICSERV);
-
-		if(err || !is_valid_hostname(resolved_host)) {
-			freeaddrinfo(ai_in);
-			continue;
-		}
+		struct addrinfo *ai_in = adns_blocking_request(mesh, xstrdup(hostname[i]), xstrdup(port[i]), SOCK_STREAM, 5);
 
-		// Convert the hostname back to a sockaddr
-		hint.ai_family = ai_in->ai_family;
-		err = getaddrinfo(resolved_host, resolved_port, &hint, &ai_out);
-
-		if(err || !ai_out) {
-			freeaddrinfo(ai_in);
+		if(!ai_in) {
 			continue;
 		}
 
-		// Check if it's still the same sockaddr
-		if(ai_in->ai_addrlen != ai_out->ai_addrlen || memcmp(ai_in->ai_addr, ai_out->ai_addr, ai_in->ai_addrlen)) {
-			freeaddrinfo(ai_in);
-			freeaddrinfo(ai_out);
-			continue;
+		// Remember the address(es)
+		for(struct addrinfo *aip = ai_in; aip; aip = aip->ai_next) {
+			node_add_recent_address(mesh, mesh->self, (sockaddr_t *)aip->ai_addr);
 		}
 
-		// Yes: replace the hostname with the resolved one
-		free(hostname[i]);
-		hostname[i] = xstrdup(resolved_host);
-
 		freeaddrinfo(ai_in);
-		freeaddrinfo(ai_out);
+		continue;
 	}
 
 	// Remove duplicates again, since IPv4 and IPv6 addresses might map to the same hostname
-	remove_duplicate_hostnames(hostname, port, 4);
+	remove_duplicate_hostnames(hostname, port, n);
 
 	// Concatenate all unique address to the hostport string
-	for(int i = 0; i < 4; i++) {
+	for(int i = 0; i < n; i++) {
 		if(!hostname[i]) {
 			continue;
 		}
@@ -575,7 +597,7 @@ static char *get_my_hostname(meshlink_handle_t *mesh, uint32_t flags) {
 	return hostport;
 }
 
-static bool try_bind(int port) {
+static bool try_bind(meshlink_handle_t *mesh, int port) {
 	struct addrinfo *ai = NULL;
 	struct addrinfo hint = {
 		.ai_flags = AI_PASSIVE,
@@ -596,16 +618,9 @@ static bool try_bind(int port) {
 	for(struct addrinfo *aip = ai; aip; aip = aip->ai_next) {
 		/* Try to bind to TCP. */
 
-		int tcp_fd = socket(aip->ai_family, SOCK_STREAM, IPPROTO_TCP);
+		int tcp_fd = setup_tcp_listen_socket(mesh, aip);
 
 		if(tcp_fd == -1) {
-			continue;
-		}
-
-		int result = bind(tcp_fd, aip->ai_addr, aip->ai_addrlen);
-		closesocket(tcp_fd);
-
-		if(result) {
 			if(errno == EADDRINUSE) {
 				/* If this port is in use for any address family, avoid it. */
 				success = false;
@@ -617,21 +632,16 @@ static bool try_bind(int port) {
 
 		/* If TCP worked, then we require that UDP works as well. */
 
-		int udp_fd = socket(aip->ai_family, SOCK_DGRAM, IPPROTO_UDP);
+		int udp_fd = setup_udp_listen_socket(mesh, aip);
 
 		if(udp_fd == -1) {
+			closesocket(tcp_fd);
 			success = false;
 			break;
 		}
 
-		result = bind(udp_fd, aip->ai_addr, aip->ai_addrlen);
+		closesocket(tcp_fd);
 		closesocket(udp_fd);
-
-		if(result) {
-			success = false;
-			break;
-		}
-
 		success = true;
 	}
 
@@ -641,9 +651,9 @@ static bool try_bind(int port) {
 
 int check_port(meshlink_handle_t *mesh) {
 	for(int i = 0; i < 1000; i++) {
-		int port = 0x1000 + prng(mesh, 0x8000);
+		int port = 0x1000 + prng(mesh, 0x7000);
 
-		if(try_bind(port)) {
+		if(try_bind(mesh, port)) {
 			free(mesh->myport);
 			xasprintf(&mesh->myport, "%d", port);
 			return port;
@@ -682,7 +692,7 @@ static bool write_main_config_files(meshlink_handle_t *mesh) {
 	}
 
 	/* Write our own host config file */
-	if(!node_write_config(mesh, mesh->self)) {
+	if(!node_write_config(mesh, mesh->self, true)) {
 		return false;
 	}
 
@@ -714,24 +724,28 @@ 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;
 	}
 
@@ -739,6 +753,8 @@ 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
@@ -753,39 +769,39 @@ 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)) {
-			logger(mesh, MESHLINK_DEBUG, "Secondary chunk would overwrite our own host config file.\n");
-			free(name);
+		if(!strcmp(name2, mesh->name)) {
+			logger(mesh, MESHLINK_ERROR, "Secondary chunk would overwrite our own host config file.\n");
+			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);
@@ -810,7 +826,7 @@ static bool finalize_join(join_state_t *state, const void *buf, uint16_t len) {
 		n->last_reachable = 0;
 		n->last_unreachable = 0;
 
-		if(!node_write_config(mesh, n)) {
+		if(!node_write_config(mesh, n, true)) {
 			free_node(n);
 			return false;
 		}
@@ -819,7 +835,7 @@ 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;
 	}
 
@@ -931,7 +947,7 @@ 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;
@@ -995,7 +1011,7 @@ static bool ecdsa_keygen(meshlink_handle_t *mesh) {
 	mesh->invitation_key = ecdsa_generate();
 
 	if(!mesh->private_key || !mesh->invitation_key) {
-		logger(mesh, MESHLINK_DEBUG, "Error during key generation!\n");
+		logger(mesh, MESHLINK_ERROR, "Error during key generation!\n");
 		meshlink_errno = MESHLINK_EINTERNAL;
 		return false;
 	}
@@ -1005,10 +1021,18 @@ static bool ecdsa_keygen(meshlink_handle_t *mesh) {
 	return true;
 }
 
-static struct timeval idle(event_loop_t *loop, void *data) {
+static bool timespec_lt(const struct timespec *a, const struct timespec *b) {
+	if(a->tv_sec == b->tv_sec) {
+		return a->tv_nsec < b->tv_nsec;
+	} else {
+		return a->tv_sec < b->tv_sec;
+	}
+}
+
+static struct timespec idle(event_loop_t *loop, void *data) {
 	(void)loop;
 	meshlink_handle_t *mesh = data;
-	struct timeval t, tmin = {3600, 0};
+	struct timespec t, tmin = {3600, 0};
 
 	for splay_each(node_t, n, mesh->nodes) {
 		if(!n->utcp) {
@@ -1017,7 +1041,7 @@ static struct timeval idle(event_loop_t *loop, void *data) {
 
 		t = utcp_timeout(n->utcp);
 
-		if(timercmp(&t, &tmin, <)) {
+		if(timespec_lt(&t, &tmin)) {
 			tmin = t;
 		}
 	}
@@ -1124,9 +1148,6 @@ 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;
@@ -1135,8 +1156,6 @@ static bool meshlink_read_config(meshlink_handle_t *mesh) {
 		return false;
 	}
 
-#endif
-
 	free(mesh->name);
 	mesh->name = name;
 	xasprintf(&mesh->myport, "%u", myport);
@@ -1171,12 +1190,13 @@ static void *setup_network_in_netns_thread(void *arg) {
 	}
 
 	bool success = setup_network(mesh);
-	add_local_addresses(mesh);
 	return success ? arg : NULL;
 }
 #endif // HAVE_SETNS
 
 meshlink_open_params_t *meshlink_open_params_init(const char *confbase, const char *name, const char *appname, dev_class_t devclass) {
+	logger(NULL, MESHLINK_DEBUG, "meshlink_open_params_init(%s, %s, %s, %d)", confbase, name, appname, devclass);
+
 	if(!confbase || !*confbase) {
 		logger(NULL, MESHLINK_ERROR, "No confbase given!\n");
 		meshlink_errno = MESHLINK_EINVAL;
@@ -1195,13 +1215,7 @@ 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;
@@ -1216,15 +1230,19 @@ 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;
 
+	xasprintf(&params->lock_filename, "%s" SLASH "meshlink.lock", confbase);
+
 	return params;
 }
 
 bool meshlink_open_params_set_netns(meshlink_open_params_t *params, int netns) {
+	logger(NULL, MESHLINK_DEBUG, "meshlink_open_params_set_netnst(%d)", netns);
+
 	if(!params) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
@@ -1236,6 +1254,8 @@ bool meshlink_open_params_set_netns(meshlink_open_params_t *params, int netns) {
 }
 
 bool meshlink_open_params_set_storage_key(meshlink_open_params_t *params, const void *key, size_t keylen) {
+	logger(NULL, MESHLINK_DEBUG, "meshlink_open_params_set_storage_key(%p, %zu)", key, keylen);
+
 	if(!params) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
@@ -1253,14 +1273,45 @@ bool meshlink_open_params_set_storage_key(meshlink_open_params_t *params, const
 	return true;
 }
 
+bool meshlink_open_params_set_storage_policy(meshlink_open_params_t *params, meshlink_storage_policy_t policy) {
+	logger(NULL, MESHLINK_DEBUG, "meshlink_open_params_set_storage_policy(%d)", policy);
+
+	if(!params) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
+	params->storage_policy = policy;
+
+	return true;
+}
+
+bool meshlink_open_params_set_lock_filename(meshlink_open_params_t *params, const char *filename) {
+	logger(NULL, MESHLINK_DEBUG, "meshlink_open_params_set_lock_filename(%s)", filename);
+
+	if(!params || !filename) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
+	free(params->lock_filename);
+	params->lock_filename = xstrdup(filename);
+
+	return true;
+}
+
 bool meshlink_encrypted_key_rotate(meshlink_handle_t *mesh, const void *new_key, size_t new_keylen) {
+	logger(NULL, MESHLINK_DEBUG, "meshlink_encrypted_key_rotate(%p, %zu)", new_key, new_keylen);
+
 	if(!mesh || !new_key || !new_keylen) {
 		logger(mesh, MESHLINK_ERROR, "Invalid arguments given!\n");
 		meshlink_errno = MESHLINK_EINVAL;
 		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;
@@ -1324,6 +1375,8 @@ bool meshlink_encrypted_key_rotate(meshlink_handle_t *mesh, const void *new_key,
 }
 
 void meshlink_open_params_free(meshlink_open_params_t *params) {
+	logger(NULL, MESHLINK_DEBUG, "meshlink_open_params_free()");
+
 	if(!params) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
@@ -1332,54 +1385,65 @@ void meshlink_open_params_free(meshlink_open_params_t *params) {
 	free(params->confbase);
 	free(params->name);
 	free(params->appname);
+	free(params->lock_filename);
 
 	free(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) {
+	logger(NULL, MESHLINK_DEBUG, "meshlink_open(%s, %s, %s, %d)", confbase, name, appname, devclass);
+
 	if(!confbase || !*confbase) {
 		logger(NULL, MESHLINK_ERROR, "No confbase 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));
+	char lock_filename[PATH_MAX];
+	snprintf(lock_filename, sizeof(lock_filename), "%s" SLASH "meshlink.lock", confbase);
 
-	params.confbase = (char *)confbase;
-	params.name = (char *)name;
-	params.appname = (char *)appname;
-	params.devclass = devclass;
-	params.netns = -1;
+	/* Create a temporary struct on the stack, to avoid allocating and freeing one. */
+	meshlink_open_params_t params = {
+		.confbase = (char *)confbase,
+		.lock_filename = lock_filename,
+		.name = (char *)name,
+		.appname = (char *)appname,
+		.devclass = devclass,
+		.netns = -1,
+	};
 
 	return meshlink_open_ex(&params);
 }
 
 meshlink_handle_t *meshlink_open_encrypted(const char *confbase, const char *name, const char *appname, dev_class_t devclass, const void *key, size_t keylen) {
+	logger(NULL, MESHLINK_DEBUG, "meshlink_open_encrypted(%s, %s, %s, %d, %p, %zu)", confbase, name, appname, devclass, key, keylen);
+
 	if(!confbase || !*confbase) {
 		logger(NULL, MESHLINK_ERROR, "No confbase 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));
+	char lock_filename[PATH_MAX];
+	snprintf(lock_filename, sizeof(lock_filename), "%s" SLASH "meshlink.lock", confbase);
 
-	params.confbase = (char *)confbase;
-	params.name = (char *)name;
-	params.appname = (char *)appname;
-	params.devclass = devclass;
-	params.netns = -1;
+	/* Create a temporary struct on the stack, to avoid allocating and freeing one. */
+	meshlink_open_params_t params = {
+		.confbase = (char *)confbase,
+		.lock_filename = lock_filename,
+		.name = (char *)name,
+		.appname = (char *)appname,
+		.devclass = devclass,
+		.netns = -1,
+	};
 
 	if(!meshlink_open_params_set_storage_key(&params, key, keylen)) {
 		return false;
@@ -1389,24 +1453,53 @@ 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) {
-	/* Create a temporary struct on the stack, to avoid allocating and freeing one. */
-	meshlink_open_params_t params;
-	memset(&params, 0, sizeof(params));
+	logger(NULL, MESHLINK_DEBUG, "meshlink_open_ephemeral(%s, %s, %d)", name, appname, 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;
+	}
 
-	params.name = (char *)name;
-	params.appname = (char *)appname;
-	params.devclass = devclass;
-	params.netns = -1;
+	/* Create a temporary struct on the stack, to avoid allocating and freeing one. */
+	meshlink_open_params_t params = {
+		.name = (char *)name,
+		.appname = (char *)appname,
+		.devclass = devclass,
+		.netns = -1,
+	};
 
 	return meshlink_open_ex(&params);
 }
 
 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");
+	logger(NULL, MESHLINK_DEBUG, "meshlink_open_ex()");
 
+	// Validate arguments provided by the application
 	if(!params->appname || !*params->appname) {
 		logger(NULL, MESHLINK_ERROR, "No appname given!\n");
 		meshlink_errno = MESHLINK_EINVAL;
@@ -1419,18 +1512,10 @@ 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) {
@@ -1453,12 +1538,13 @@ meshlink_handle_t *meshlink_open_ex(const meshlink_open_params_t *params) {
 
 	mesh->appname = xstrdup(params->appname);
 	mesh->devclass = params->devclass;
-	mesh->discovery = true;
+	mesh->discovery.enabled = true;
 	mesh->invitation_timeout = 604800; // 1 week
 	mesh->netns = params->netns;
 	mesh->submeshes = NULL;
 	mesh->log_cb = global_log_cb;
 	mesh->log_level = global_log_level;
+	mesh->packet = xmalloc(sizeof(vpn_packet_t));
 
 	randomize(&mesh->prng_state, sizeof(mesh->prng_state));
 
@@ -1468,9 +1554,7 @@ 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) {
@@ -1484,11 +1568,18 @@ 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_cond_init(&mesh->adns_cond, NULL);
 
 	mesh->threadstarted = false;
 	event_loop_init(&mesh->loop);
@@ -1497,19 +1588,30 @@ meshlink_handle_t *meshlink_open_ex(const meshlink_open_params_t *params) {
 	meshlink_queue_init(&mesh->outpacketqueue);
 
 	// Atomically lock the configuration directory.
-	if(!main_config_lock(mesh)) {
+	if(!main_config_lock(mesh, params->lock_filename)) {
 		meshlink_close(mesh);
 		return NULL;
 	}
 
 	// If no configuration exists yet, create it.
 
+	bool new_configuration = false;
+
 	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);
 			return NULL;
 		}
+
+		new_configuration = true;
 	} else {
 		if(!meshlink_read_config(mesh)) {
 			logger(NULL, MESHLINK_ERROR, "Cannot read main configuration\n");
@@ -1518,6 +1620,8 @@ meshlink_handle_t *meshlink_open_ex(const meshlink_open_params_t *params) {
 		}
 	}
 
+	mesh->storage_policy = params->storage_policy;
+
 #ifdef HAVE_MINGW
 	struct WSAData wsa_state;
 	WSAStartup(MAKEWORD(2, 2), &wsa_state);
@@ -1544,7 +1648,6 @@ meshlink_handle_t *meshlink_open_ex(const meshlink_open_params_t *params) {
 #endif // HAVE_SETNS
 	} else {
 		success = setup_network(mesh);
-		add_local_addresses(mesh);
 	}
 
 	if(!success) {
@@ -1555,7 +1658,7 @@ meshlink_handle_t *meshlink_open_ex(const meshlink_open_params_t *params) {
 
 	add_local_addresses(mesh);
 
-	if(!node_write_config(mesh, mesh->self)) {
+	if(!node_write_config(mesh, mesh->self, new_configuration)) {
 		logger(NULL, MESHLINK_ERROR, "Cannot update configuration\n");
 		return NULL;
 	}
@@ -1566,7 +1669,9 @@ meshlink_handle_t *meshlink_open_ex(const meshlink_open_params_t *params) {
 	return mesh;
 }
 
-meshlink_submesh_t *meshlink_submesh_open(meshlink_handle_t  *mesh, const char *submesh) {
+meshlink_submesh_t *meshlink_submesh_open(meshlink_handle_t *mesh, const char *submesh) {
+	logger(NULL, MESHLINK_DEBUG, "meshlink_submesh_open(%s)", submesh);
+
 	meshlink_submesh_t *s = NULL;
 
 	if(!mesh) {
@@ -1582,7 +1687,9 @@ 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);
 
@@ -1608,32 +1715,34 @@ static void *meshlink_main_loop(void *arg) {
 #endif // HAVE_SETNS
 	}
 
-#if HAVE_CATTA
-
-	if(mesh->discovery) {
+	if(mesh->discovery.enabled) {
 		discovery_start(mesh);
 	}
 
-#endif
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(mesh->thread_status_cb) {
+		mesh->thread_status_cb(mesh, true);
+	}
 
 	logger(mesh, MESHLINK_DEBUG, "Starting main_loop...\n");
 	pthread_cond_broadcast(&mesh->cond);
 	main_loop(mesh);
 	logger(mesh, MESHLINK_DEBUG, "main_loop returned.\n");
 
-	pthread_mutex_unlock(&mesh->mutex);
+	if(mesh->thread_status_cb) {
+		mesh->thread_status_cb(mesh, false);
+	}
 
-#if HAVE_CATTA
+	pthread_mutex_unlock(&mesh->mutex);
 
 	// Stop discovery
-	if(mesh->discovery) {
+	if(mesh->discovery.enabled) {
 		discovery_stop(mesh);
 	}
 
-#endif
-
 	return NULL;
 }
 
@@ -1645,7 +1754,9 @@ 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);
@@ -1664,24 +1775,35 @@ 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
 	if(!mesh->name) {
-		logger(mesh, MESHLINK_DEBUG, "No name given!\n");
+		logger(mesh, MESHLINK_ERROR, "No name given!\n");
 		meshlink_errno = MESHLINK_EINVAL;
 		pthread_mutex_unlock(&mesh->mutex);
 		return false;
 	}
 
 	init_outgoings(mesh);
+	init_adns(mesh);
 
 	// Start the main thread
 
 	event_loop_start(&mesh->loop);
 
-	if(pthread_create(&mesh->thread, NULL, meshlink_main_loop, mesh) != 0) {
-		logger(mesh, MESHLINK_DEBUG, "Could not start thread: %s\n", strerror(errno));
+	// 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_ERROR, "Could not start thread: %s\n", strerror(errno));
 		memset(&mesh->thread, 0, sizeof(mesh)->thread);
 		meshlink_errno = MESHLINK_EINTERNAL;
 		event_loop_stop(&mesh->loop);
@@ -1700,13 +1822,16 @@ bool meshlink_start(meshlink_handle_t *mesh) {
 }
 
 void meshlink_stop(meshlink_handle_t *mesh) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_stop()\n");
+
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
-	logger(mesh, MESHLINK_DEBUG, "meshlink_stop called\n");
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	// Shut down the main thread
 	event_loop_stop(&mesh->loop);
@@ -1729,8 +1854,14 @@ 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;
 	}
@@ -1745,6 +1876,7 @@ void meshlink_stop(meshlink_handle_t *mesh) {
 		}
 	}
 
+	exit_adns(mesh);
 	exit_outgoings(mesh);
 
 	// Ensure we are considered unreachable
@@ -1756,7 +1888,9 @@ void meshlink_stop(meshlink_handle_t *mesh) {
 	if(mesh->nodes) {
 		for splay_each(node_t, n, mesh->nodes) {
 			if(n->status.dirty) {
-				n->status.dirty = !node_write_config(mesh, n);
+				if(!node_write_config(mesh, n, false)) {
+					// ignore
+				}
 			}
 		}
 	}
@@ -1765,6 +1899,8 @@ void meshlink_stop(meshlink_handle_t *mesh) {
 }
 
 void meshlink_close(meshlink_handle_t *mesh) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_close()\n");
+
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
@@ -1774,7 +1910,9 @@ 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.
 
@@ -1809,6 +1947,7 @@ void meshlink_close(meshlink_handle_t *mesh) {
 	free(mesh->confbase);
 	free(mesh->config_key);
 	free(mesh->external_address_url);
+	free(mesh->packet);
 	ecdsa_free(mesh->private_key);
 
 	if(mesh->invitation_addresses) {
@@ -1825,25 +1964,29 @@ void meshlink_close(meshlink_handle_t *mesh) {
 	free(mesh);
 }
 
-bool meshlink_destroy(const char *confbase) {
-	if(!confbase) {
+bool meshlink_destroy_ex(const meshlink_open_params_t *params) {
+	logger(NULL, MESHLINK_DEBUG, "meshlink_destroy_ex()\n");
+
+	if(!params) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
 
+	if(!params->confbase) {
+		/* Ephemeral instances */
+		return true;
+	}
+
 	/* Exit early if the confbase directory itself doesn't exist */
-	if(access(confbase, F_OK) && errno == ENOENT) {
+	if(access(params->confbase, F_OK) && errno == ENOENT) {
 		return true;
 	}
 
 	/* Take the lock the same way meshlink_open() would. */
-	char lockfilename[PATH_MAX];
-	snprintf(lockfilename, sizeof(lockfilename), "%s" SLASH "meshlink.lock", confbase);
-
-	FILE *lockfile = fopen(lockfilename, "w+");
+	FILE *lockfile = fopen(params->lock_filename, "w+");
 
 	if(!lockfile) {
-		logger(NULL, MESHLINK_ERROR, "Could not open lock file %s: %s", lockfilename, strerror(errno));
+		logger(NULL, MESHLINK_ERROR, "Could not open lock file %s: %s", params->lock_filename, strerror(errno));
 		meshlink_errno = MESHLINK_ESTORAGE;
 		return false;
 	}
@@ -1857,7 +2000,7 @@ bool meshlink_destroy(const char *confbase) {
 #else
 
 	if(flock(fileno(lockfile), LOCK_EX | LOCK_NB) != 0) {
-		logger(NULL, MESHLINK_ERROR, "Configuration directory %s still in use\n", lockfilename);
+		logger(NULL, MESHLINK_ERROR, "Configuration directory %s still in use\n", params->lock_filename);
 		fclose(lockfile);
 		meshlink_errno = MESHLINK_EBUSY;
 		return false;
@@ -1865,13 +2008,13 @@ bool meshlink_destroy(const char *confbase) {
 
 #endif
 
-	if(!config_destroy(confbase, "current") || !config_destroy(confbase, "new") || !config_destroy(confbase, "old")) {
-		logger(NULL, MESHLINK_ERROR, "Cannot remove sub-directories in %s: %s\n", confbase, strerror(errno));
+	if(!config_destroy(params->confbase, "current") || !config_destroy(params->confbase, "new") || !config_destroy(params->confbase, "old")) {
+		logger(NULL, MESHLINK_ERROR, "Cannot remove sub-directories in %s: %s\n", params->confbase, strerror(errno));
 		return false;
 	}
 
-	if(unlink(lockfilename)) {
-		logger(NULL, MESHLINK_ERROR, "Cannot remove lock file %s: %s\n", lockfilename, strerror(errno));
+	if(unlink(params->lock_filename)) {
+		logger(NULL, MESHLINK_ERROR, "Cannot remove lock file %s: %s\n", params->lock_filename, strerror(errno));
 		fclose(lockfile);
 		meshlink_errno = MESHLINK_ESTORAGE;
 		return false;
@@ -1879,8 +2022,8 @@ bool meshlink_destroy(const char *confbase) {
 
 	fclose(lockfile);
 
-	if(!sync_path(confbase)) {
-		logger(NULL, MESHLINK_ERROR, "Cannot sync directory %s: %s\n", confbase, strerror(errno));
+	if(!sync_path(params->confbase)) {
+		logger(NULL, MESHLINK_ERROR, "Cannot sync directory %s: %s\n", params->confbase, strerror(errno));
 		meshlink_errno = MESHLINK_ESTORAGE;
 		return false;
 	}
@@ -1888,64 +2031,108 @@ bool meshlink_destroy(const char *confbase) {
 	return true;
 }
 
+bool meshlink_destroy(const char *confbase) {
+	logger(NULL, MESHLINK_DEBUG, "meshlink_destroy(%s)", confbase);
+
+	char lock_filename[PATH_MAX];
+	snprintf(lock_filename, sizeof(lock_filename), "%s" SLASH "meshlink.lock", confbase);
+
+	meshlink_open_params_t params = {
+		.confbase = (char *)confbase,
+		.lock_filename = lock_filename,
+	};
+
+	return meshlink_destroy_ex(&params);
+}
+
 void meshlink_set_receive_cb(meshlink_handle_t *mesh, meshlink_receive_cb_t cb) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_receive_cb(%p)", (void *)(intptr_t)cb);
+
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	mesh->receive_cb = cb;
 	pthread_mutex_unlock(&mesh->mutex);
 }
 
 void meshlink_set_connection_try_cb(meshlink_handle_t *mesh, meshlink_connection_try_cb_t cb) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_connection_try_cb(%p)", (void *)(intptr_t)cb);
+
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	mesh->connection_try_cb = cb;
 	pthread_mutex_unlock(&mesh->mutex);
 }
 
 void meshlink_set_node_status_cb(meshlink_handle_t *mesh, meshlink_node_status_cb_t cb) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_node_status_cb(%p)", (void *)(intptr_t)cb);
+
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	mesh->node_status_cb = cb;
 	pthread_mutex_unlock(&mesh->mutex);
 }
 
 void meshlink_set_node_pmtu_cb(meshlink_handle_t *mesh, meshlink_node_pmtu_cb_t cb) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_node_pmtu_cb(%p)", (void *)(intptr_t)cb);
+
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	mesh->node_pmtu_cb = cb;
 	pthread_mutex_unlock(&mesh->mutex);
 }
 
 void meshlink_set_node_duplicate_cb(meshlink_handle_t *mesh, meshlink_node_duplicate_cb_t cb) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_node_duplicate_cb(%p)", (void *)(intptr_t)cb);
+
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
 		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) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_log_cb(%p)", (void *)(intptr_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);
@@ -1956,30 +2143,57 @@ void meshlink_set_log_cb(meshlink_handle_t *mesh, meshlink_log_level_t level, me
 }
 
 void meshlink_set_error_cb(struct meshlink_handle *mesh, meshlink_error_cb_t cb) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_error_cb(%p)", (void *)(intptr_t)cb);
+
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	mesh->error_cb = cb;
 	pthread_mutex_unlock(&mesh->mutex);
 }
 
-bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const void *data, size_t len) {
-	meshlink_packethdr_t *hdr;
+void meshlink_set_blacklisted_cb(struct meshlink_handle *mesh, meshlink_blacklisted_cb_t cb) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_blacklisted_cb(%p)", (void *)(intptr_t)cb);
 
-	// Validate arguments
-	if(!mesh || !destination || len >= MAXSIZE - sizeof(*hdr)) {
+	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
-		return false;
+		return;
 	}
 
-	if(!len) {
-		return true;
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
 	}
 
-	if(!data) {
+	mesh->blacklisted_cb = cb;
+	pthread_mutex_unlock(&mesh->mutex);
+}
+
+void meshlink_set_thread_status_cb(struct meshlink_handle *mesh, meshlink_thread_status_cb_t cb) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_thread_status_cb(%p)", (void *)(intptr_t)cb);
+
+	if(!mesh) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return;
+	}
+
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
+	mesh->thread_status_cb = cb;
+	pthread_mutex_unlock(&mesh->mutex);
+}
+
+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)) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
@@ -1993,13 +2207,6 @@ bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const
 	}
 
 	// Prepare the packet
-	vpn_packet_t *packet = malloc(sizeof(*packet));
-
-	if(!packet) {
-		meshlink_errno = MESHLINK_ENOMEM;
-		return false;
-	}
-
 	packet->probe = false;
 	packet->tcp = false;
 	packet->len = len + sizeof(*hdr);
@@ -2008,11 +2215,62 @@ bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const
 	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);
 
+	return true;
+}
+
+static bool meshlink_send_immediate(meshlink_handle_t *mesh, meshlink_node_t *destination, const void *data, size_t len) {
+	assert(mesh);
+	assert(destination);
+	assert(data);
+	assert(len);
+
+	// Prepare the packet
+	if(!prepare_packet(mesh, destination, data, len, mesh->packet)) {
+		return false;
+	}
+
+	// Send it immediately
+	route(mesh, mesh->self, mesh->packet);
+
+	return true;
+}
+
+bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const void *data, size_t len) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_send(%s, %p, %zu)", destination ? destination->name : "(null)", data, len);
+
+	// Validate arguments
+	if(!mesh || !destination) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
+	if(!len) {
+		return true;
+	}
+
+	if(!data) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
+	// Prepare the packet
+	vpn_packet_t *packet = malloc(sizeof(*packet));
+
+	if(!packet) {
+		meshlink_errno = MESHLINK_ENOMEM;
+		return false;
+	}
+
+	if(!prepare_packet(mesh, destination, data, len, packet)) {
+		free(packet);
+		return false;
+	}
+
 	// Queue it
 	if(!meshlink_queue_push(&mesh->outpacketqueue, packet)) {
 		free(packet);
@@ -2020,6 +2278,8 @@ bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const
 		return false;
 	}
 
+	logger(mesh, MESHLINK_DEBUG, "Adding packet of %zu bytes to packet queue", len);
+
 	// Notify event loop
 	signal_trigger(&mesh->loop, &mesh->datafromapp);
 
@@ -2029,17 +2289,14 @@ bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const
 void meshlink_send_from_queue(event_loop_t *loop, void *data) {
 	(void)loop;
 	meshlink_handle_t *mesh = data;
-	vpn_packet_t *packet = meshlink_queue_pop(&mesh->outpacketqueue);
 
-	if(!packet) {
-		return;
-	}
-
-	mesh->self->in_packets++;
-	mesh->self->in_bytes += packet->len;
-	route(mesh, mesh->self, packet);
+	logger(mesh, MESHLINK_DEBUG, "Flushing the packet queue");
 
-	free(packet);
+	for(vpn_packet_t *packet; (packet = meshlink_queue_pop(&mesh->outpacketqueue));) {
+		logger(mesh, MESHLINK_DEBUG, "Removing packet of %d bytes from packet queue", packet->len);
+		route(mesh, mesh->self, packet);
+		free(packet);
+	}
 }
 
 ssize_t meshlink_get_pmtu(meshlink_handle_t *mesh, meshlink_node_t *destination) {
@@ -2048,7 +2305,9 @@ 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;
 
@@ -2071,7 +2330,9 @@ 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;
 
@@ -2108,7 +2369,10 @@ 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);
 
@@ -2127,7 +2391,10 @@ 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);
 
@@ -2147,7 +2414,9 @@ 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));
@@ -2172,7 +2441,9 @@ 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;
 
@@ -2219,6 +2490,10 @@ 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;
@@ -2281,6 +2556,15 @@ 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;
@@ -2289,7 +2573,9 @@ 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;
 
@@ -2298,6 +2584,47 @@ dev_class_t meshlink_get_node_dev_class(meshlink_handle_t *mesh, meshlink_node_t
 	return devclass;
 }
 
+bool meshlink_get_node_tiny(meshlink_handle_t *mesh, meshlink_node_t *node) {
+	if(!mesh || !node) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return -1;
+	}
+
+	bool tiny;
+
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
+	tiny = ((node_t *)node)->status.tiny;
+
+	pthread_mutex_unlock(&mesh->mutex);
+
+	return tiny;
+}
+
+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;
@@ -2322,7 +2649,10 @@ 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) {
@@ -2339,6 +2669,8 @@ bool meshlink_get_node_reachability(struct meshlink_handle *mesh, struct meshlin
 }
 
 bool meshlink_sign(meshlink_handle_t *mesh, const void *data, size_t len, void *signature, size_t *siglen) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_sign(%p, %zu, %p, %p)", data, len, signature, (void *)siglen);
+
 	if(!mesh || !data || !len || !signature || !siglen) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
@@ -2349,7 +2681,9 @@ 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;
@@ -2363,6 +2697,8 @@ bool meshlink_sign(meshlink_handle_t *mesh, const void *data, size_t len, void *
 }
 
 bool meshlink_verify(meshlink_handle_t *mesh, meshlink_node_t *source, const void *data, size_t len, const void *signature, size_t siglen) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_verify(%p, %zu, %p, %zu)", data, len, signature, siglen);
+
 	if(!mesh || !source || !data || !len || !signature) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
@@ -2373,7 +2709,9 @@ 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;
 
@@ -2391,7 +2729,9 @@ 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);
 
@@ -2405,38 +2745,71 @@ static bool refresh_invitation_key(meshlink_handle_t *mesh) {
 }
 
 bool meshlink_set_canonical_address(meshlink_handle_t *mesh, meshlink_node_t *node, const char *address, const char *port) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_canonical_address(%s, %s, %s)", node ? node->name : "(null)", address ? address : "(null)", port ? port : "(null)");
+
 	if(!mesh || !node || !address) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
 
 	if(!is_valid_hostname(address)) {
-		logger(mesh, MESHLINK_DEBUG, "Invalid character in address: %s\n", address);
+		logger(mesh, MESHLINK_ERROR, "Invalid character in address: %s", address);
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
+	if((node_t *)node != mesh->self && !port) {
+		logger(mesh, MESHLINK_ERROR, "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_ERROR, "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);
 	n->canonical_address = canonical_address;
 
-	if(!node_write_config(mesh, n)) {
+	if(!node_write_config(mesh, n, false)) {
+		pthread_mutex_unlock(&mesh->mutex);
+		return false;
+	}
+
+	pthread_mutex_unlock(&mesh->mutex);
+
+	return config_sync(mesh, "current");
+}
+
+bool meshlink_clear_canonical_address(meshlink_handle_t *mesh, meshlink_node_t *node) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_clear_canonical_address(%s)", node ? node->name : "(null)");
+
+	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, false)) {
 		pthread_mutex_unlock(&mesh->mutex);
 		return false;
 	}
@@ -2447,19 +2820,21 @@ bool meshlink_set_canonical_address(meshlink_handle_t *mesh, meshlink_node_t *no
 }
 
 bool meshlink_add_invitation_address(struct meshlink_handle *mesh, const char *address, const char *port) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_add_invitation_address(%s, %s)", address ? address : "(null)", port ? port : "(null)");
+
 	if(!mesh || !address) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
 
 	if(!is_valid_hostname(address)) {
-		logger(mesh, MESHLINK_DEBUG, "Invalid character in address: %s\n", address);
+		logger(mesh, MESHLINK_ERROR, "Invalid character in address: %s\n", address);
 		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_ERROR, "Invalid character in port: %s\n", address);
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
@@ -2467,16 +2842,14 @@ bool meshlink_add_invitation_address(struct meshlink_handle *mesh, const char *a
 	char *combo;
 
 	if(port) {
-		if(strchr(address, ':')) {
-			xasprintf(&combo, "[%s]:%s", address, port);
-		} else {
-			xasprintf(&combo, "%s:%s", address, port);
-		}
+		xasprintf(&combo, "%s/%s", address, port);
 	} else {
 		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);
@@ -2489,12 +2862,16 @@ bool meshlink_add_invitation_address(struct meshlink_handle *mesh, const char *a
 }
 
 void meshlink_clear_invitation_addresses(struct meshlink_handle *mesh) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_clear_invitation_addresses()");
+
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	if(mesh->invitation_addresses) {
 		list_delete_list(mesh->invitation_addresses);
@@ -2505,10 +2882,14 @@ void meshlink_clear_invitation_addresses(struct meshlink_handle *mesh) {
 }
 
 bool meshlink_add_address(meshlink_handle_t *mesh, const char *address) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_add_address(%s)", address ? address : "(null)");
+
 	return meshlink_set_canonical_address(mesh, (meshlink_node_t *)mesh->self, address, NULL);
 }
 
 bool meshlink_add_external_address(meshlink_handle_t *mesh) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_add_external_address()");
+
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
@@ -2539,7 +2920,10 @@ 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);
 
@@ -2547,6 +2931,8 @@ int meshlink_get_port(meshlink_handle_t *mesh) {
 }
 
 bool meshlink_set_port(meshlink_handle_t *mesh, int port) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_port(%d)", port);
+
 	if(!mesh || port < 0 || port >= 65536 || mesh->threadstarted) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
@@ -2556,7 +2942,7 @@ bool meshlink_set_port(meshlink_handle_t *mesh, int port) {
 		return true;
 	}
 
-	if(!try_bind(port)) {
+	if(!try_bind(mesh, port)) {
 		meshlink_errno = MESHLINK_ENETWORK;
 		return false;
 	}
@@ -2565,7 +2951,9 @@ 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;
@@ -2612,10 +3000,14 @@ done:
 }
 
 void meshlink_set_invitation_timeout(meshlink_handle_t *mesh, int timeout) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_invitation_timeout(%d)", timeout);
+
 	mesh->invitation_timeout = timeout;
 }
 
 char *meshlink_invite_ex(meshlink_handle_t *mesh, meshlink_submesh_t *submesh, const char *name, uint32_t flags) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_invite_ex(%s, %s, %u)", submesh ? submesh->name : "(null)", name ? name : "(null)", flags);
+
 	meshlink_submesh_t *s = NULL;
 
 	if(!mesh) {
@@ -2627,7 +3019,7 @@ char *meshlink_invite_ex(meshlink_handle_t *mesh, meshlink_submesh_t *submesh, c
 		s = (meshlink_submesh_t *)lookup_submesh(mesh, submesh->name);
 
 		if(s != submesh) {
-			logger(mesh, MESHLINK_DEBUG, "Invalid SubMesh Handle.\n");
+			logger(mesh, MESHLINK_ERROR, "Invalid submesh handle.\n");
 			meshlink_errno = MESHLINK_EINVAL;
 			return NULL;
 		}
@@ -2635,7 +3027,9 @@ 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)) {
@@ -2679,7 +3073,7 @@ char *meshlink_invite_ex(meshlink_handle_t *mesh, meshlink_submesh_t *submesh, c
 
 	// If we changed our own host config file, write it out now
 	if(mesh->self->status.dirty) {
-		if(!node_write_config(mesh, mesh->self)) {
+		if(!node_write_config(mesh, mesh->self, false)) {
 			logger(mesh, MESHLINK_ERROR, "Could not write our own host config file!\n");
 			pthread_mutex_unlock(&mesh->mutex);
 			return NULL;
@@ -2757,15 +3151,24 @@ char *meshlink_invite_ex(meshlink_handle_t *mesh, meshlink_submesh_t *submesh, c
 }
 
 char *meshlink_invite(meshlink_handle_t *mesh, meshlink_submesh_t *submesh, const char *name) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_invite_ex(%s, %s)", submesh ? submesh->name : "(null)", name ? name : "(null)");
+
 	return meshlink_invite_ex(mesh, submesh, name, 0);
 }
 
 bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_join(%s)", invitation ? invitation : "(null)");
+
 	if(!mesh || !invitation) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
 
+	if(mesh->storage_policy == MESHLINK_STORAGE_DISABLED) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
 	join_state_t state = {
 		.mesh = mesh,
 		.sock = -1,
@@ -2777,7 +3180,9 @@ 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) {
@@ -2865,11 +3270,11 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 		}
 
 		// Connect to the meshlink daemon mentioned in the URL.
-		struct addrinfo *ai = str2addrinfo(address, port, SOCK_STREAM);
+		struct addrinfo *ai = adns_blocking_request(mesh, xstrdup(address), xstrdup(port), SOCK_STREAM, 30);
 
 		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));
@@ -2877,6 +3282,11 @@ 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)) {
@@ -2913,7 +3323,7 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 	state.blen = 0;
 
 	if(!sendline(state.sock, "0 ?%s %d.%d %s", b64key, PROT_MAJOR, PROT_MINOR, mesh->appname)) {
-		logger(mesh, MESHLINK_DEBUG, "Error sending request to %s port %s: %s\n", address, port, strerror(errno));
+		logger(mesh, MESHLINK_ERROR, "Error sending request to %s port %s: %s\n", address, port, strerror(errno));
 		meshlink_errno = MESHLINK_ENETWORK;
 		goto exit;
 	}
@@ -2924,7 +3334,7 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 	int code, hismajor, hisminor = 0;
 
 	if(!recvline(&state) || sscanf(state.line, "%d %s %d.%d", &code, hisname, &hismajor, &hisminor) < 3 || code != 0 || hismajor != PROT_MAJOR || !check_id(hisname) || !recvline(&state) || !rstrip(state.line) || sscanf(state.line, "%d ", &code) != 1 || code != ACK || strlen(state.line) < 3) {
-		logger(mesh, MESHLINK_DEBUG, "Cannot read greeting from peer\n");
+		logger(mesh, MESHLINK_ERROR, "Cannot read greeting from peer\n");
 		meshlink_errno = MESHLINK_ENETWORK;
 		goto exit;
 	}
@@ -2934,13 +3344,13 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 	char hishash[64];
 
 	if(sha512(fingerprint, strlen(fingerprint), hishash)) {
-		logger(mesh, MESHLINK_DEBUG, "Could not create hash\n%s\n", state.line + 2);
+		logger(mesh, MESHLINK_ERROR, "Could not create hash\n%s\n", state.line + 2);
 		meshlink_errno = MESHLINK_EINTERNAL;
 		goto exit;
 	}
 
 	if(memcmp(hishash, state.hash, 18)) {
-		logger(mesh, MESHLINK_DEBUG, "Peer has an invalid key!\n%s\n", state.line + 2);
+		logger(mesh, MESHLINK_ERROR, "Peer has an invalid key!\n%s\n", state.line + 2);
 		meshlink_errno = MESHLINK_EPEER;
 		goto exit;
 	}
@@ -2973,7 +3383,7 @@ 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));
+			logger(mesh, MESHLINK_ERROR, "Error reading data from %s port %s: %s\n", address, port, strerror(errno));
 			meshlink_errno = MESHLINK_ENETWORK;
 			goto exit;
 		}
@@ -2985,7 +3395,7 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 	}
 
 	if(!state.success) {
-		logger(mesh, MESHLINK_DEBUG, "Connection closed by peer, invitation cancelled.\n");
+		logger(mesh, MESHLINK_ERROR, "Connection closed by peer, invitation cancelled.\n");
 		meshlink_errno = MESHLINK_EPEER;
 		goto exit;
 	}
@@ -2999,7 +3409,7 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 	return true;
 
 invalid:
-	logger(mesh, MESHLINK_DEBUG, "Invalid invitation URL\n");
+	logger(mesh, MESHLINK_ERROR, "Invalid invitation URL\n");
 	meshlink_errno = MESHLINK_EINVAL;
 exit:
 	sptps_stop(&state.sptps);
@@ -3028,12 +3438,22 @@ 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;
 
@@ -3057,7 +3477,7 @@ char *meshlink_export(meshlink_handle_t *mesh) {
 	pthread_mutex_unlock(&mesh->mutex);
 
 	if(!packmsg_output_ok(&out)) {
-		logger(mesh, MESHLINK_DEBUG, "Error creating export data\n");
+		logger(mesh, MESHLINK_ERROR, "Error creating export data\n");
 		meshlink_errno = MESHLINK_EINTERNAL;
 		return NULL;
 	}
@@ -3072,7 +3492,7 @@ char *meshlink_export(meshlink_handle_t *mesh) {
 	packmsg_add_bin(&out2, buf, packmsg_output_size(&out, buf));
 
 	if(!packmsg_output_ok(&out2)) {
-		logger(mesh, MESHLINK_DEBUG, "Error creating export data\n");
+		logger(mesh, MESHLINK_ERROR, "Error creating export data\n");
 		meshlink_errno = MESHLINK_EINTERNAL;
 		free(buf2);
 		return NULL;
@@ -3084,6 +3504,8 @@ char *meshlink_export(meshlink_handle_t *mesh) {
 }
 
 bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_import(%p)", (const void *)data);
+
 	if(!mesh || !data) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
@@ -3094,7 +3516,8 @@ bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
 	int buflen = b64decode(data, buf, datalen);
 
 	if(!buflen) {
-		logger(mesh, MESHLINK_DEBUG, "Invalid data\n");
+		logger(mesh, MESHLINK_ERROR, "Invalid data\n");
+		free(buf);
 		meshlink_errno = MESHLINK_EPEER;
 		return false;
 	}
@@ -3103,22 +3526,25 @@ bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
 	uint32_t count = packmsg_get_array(&in);
 
 	if(!count) {
-		logger(mesh, MESHLINK_DEBUG, "Invalid data\n");
+		logger(mesh, MESHLINK_ERROR, "Invalid data\n");
+		free(buf);
 		meshlink_errno = MESHLINK_EPEER;
 		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);
 
@@ -3144,7 +3570,7 @@ 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);
@@ -3156,8 +3582,9 @@ bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
 		n->last_reachable = 0;
 		n->last_unreachable = 0;
 
-		if(!node_write_config(mesh, n)) {
+		if(!node_write_config(mesh, n, true)) {
 			free_node(n);
+			free(buf);
 			return false;
 		}
 
@@ -3200,11 +3627,15 @@ static bool blacklist(meshlink_handle_t *mesh, node_t *n) {
 	 */
 	for list_each(connection_t, c, mesh->connections) {
 		if(c->node == n) {
+			if(c->status.active) {
+				send_error(mesh, c, BLACKLISTED, "blacklisted");
+			}
+
 			shutdown(c->socket, SHUT_RDWR);
 		}
 	}
 
-	utcp_abort_all_connections(n->utcp);
+	utcp_reset_all_connections(n->utcp);
 
 	n->mtu = 0;
 	n->minmtu = 0;
@@ -3213,7 +3644,7 @@ static bool blacklist(meshlink_handle_t *mesh, node_t *n) {
 	n->status.udp_confirmed = false;
 
 	if(n->status.reachable) {
-		n->last_unreachable = mesh->loop.now.tv_sec;
+		n->last_unreachable = time(NULL);
 	}
 
 	/* Graph updates will suppress status updates for blacklisted nodes, so we need to
@@ -3223,16 +3654,23 @@ static bool blacklist(meshlink_handle_t *mesh, node_t *n) {
 		mesh->node_status_cb(mesh, (meshlink_node_t *)n, false);
 	}
 
-	return node_write_config(mesh, n) && config_sync(mesh, "current");
+	/* Remove any outstanding invitations */
+	invitation_purge_node(mesh, n->name);
+
+	return node_write_config(mesh, n, true) && config_sync(mesh, "current");
 }
 
 bool meshlink_blacklist(meshlink_handle_t *mesh, meshlink_node_t *node) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_blacklist(%s)", node ? node->name : "(null)");
+
 	if(!mesh || !node) {
 		meshlink_errno = MESHLINK_EINVAL;
 		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);
@@ -3246,12 +3684,16 @@ bool meshlink_blacklist(meshlink_handle_t *mesh, meshlink_node_t *node) {
 }
 
 bool meshlink_blacklist_by_name(meshlink_handle_t *mesh, const char *name) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_blacklist_by_name(%s)", name ? name : "(null)");
+
 	if(!mesh || !name) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	node_t *n = lookup_node(mesh, (char *)name);
 
@@ -3287,20 +3729,24 @@ static bool whitelist(meshlink_handle_t *mesh, node_t *n) {
 	n->status.blacklisted = false;
 
 	if(n->status.reachable) {
-		n->last_reachable = mesh->loop.now.tv_sec;
+		n->last_reachable = time(NULL);
 		update_node_status(mesh, n);
 	}
 
-	return node_write_config(mesh, n) && config_sync(mesh, "current");
+	return node_write_config(mesh, n, true) && config_sync(mesh, "current");
 }
 
 bool meshlink_whitelist(meshlink_handle_t *mesh, meshlink_node_t *node) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_whitelist(%s)", node ? node->name : "(null)");
+
 	if(!mesh || !node) {
 		meshlink_errno = MESHLINK_EINVAL;
 		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);
@@ -3314,12 +3760,16 @@ bool meshlink_whitelist(meshlink_handle_t *mesh, meshlink_node_t *node) {
 }
 
 bool meshlink_whitelist_by_name(meshlink_handle_t *mesh, const char *name) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_whitelist_by_name(%s)", name ? name : "(null)");
+
 	if(!mesh || !name) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	node_t *n = lookup_node(mesh, (char *)name);
 
@@ -3345,6 +3795,8 @@ void meshlink_set_default_blacklist(meshlink_handle_t *mesh, bool blacklist) {
 }
 
 bool meshlink_forget_node(meshlink_handle_t *mesh, meshlink_node_t *node) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_forget_node(%s)", node ? node->name : "(null)");
+
 	if(!mesh || !node) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
@@ -3352,7 +3804,9 @@ 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) {
@@ -3381,7 +3835,7 @@ 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);
 			}
 		}
 	}
@@ -3392,6 +3846,9 @@ 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);
 
@@ -3404,17 +3861,21 @@ bool meshlink_forget_node(meshlink_handle_t *mesh, meshlink_node_t *node) {
  * See header file for detailed comment.
  */
 void meshlink_hint_address(meshlink_handle_t *mesh, meshlink_node_t *node, const struct sockaddr *addr) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_hint_address(%s, %p)", node ? node->name : "(null)", (const void *)addr);
+
 	if(!mesh || !node || !addr) {
 		meshlink_errno = EINVAL;
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
 	node_t *n = (node_t *)node;
 
 	if(node_add_recent_address(mesh, n, (sockaddr_t *)addr)) {
-		if(!node_write_config(mesh, n)) {
+		if(!node_write_config(mesh, n, false)) {
 			logger(mesh, MESHLINK_DEBUG, "Could not update %s\n", n->name);
 		}
 	}
@@ -3427,27 +3888,62 @@ 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;
-}
 
-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);
-		}
+	if(mesh->channel_accept_cb && mesh->channel_listen_cb) {
+		return mesh->channel_listen_cb(mesh, (meshlink_node_t *)n, port);
 	} else {
-		if(aio->cb.fd) {
-			aio->cb.fd(mesh, channel, aio->fd, aio->done, aio->priv);
-		}
+		return mesh->channel_accept_cb;
 	}
 }
 
-static ssize_t channel_recv(struct utcp_connection *connection, const void *data, size_t len) {
-	meshlink_channel_t *channel = connection->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) {
-		abort();
-	}
+	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;
+		}
+	}
+
+	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) {
+	meshlink_channel_t *channel = connection->priv;
+
+	if(!channel) {
+		abort();
+	}
 
 	node_t *n = channel->node;
 	meshlink_handle_t *mesh = n->mesh;
@@ -3461,6 +3957,15 @@ 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;
 
@@ -3473,23 +3978,35 @@ 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;
 		}
 	}
@@ -3525,6 +4042,17 @@ 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 && n->mtutimeout.cb) {
+		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;
 
@@ -3533,10 +4061,12 @@ static ssize_t channel_send(struct utcp *utcp, const void *data, size_t len) {
 	}
 
 	meshlink_handle_t *mesh = n->mesh;
-	return meshlink_send(mesh, (meshlink_node_t *)n, data, len) ? (ssize_t)len : -1;
+	return meshlink_send_immediate(mesh, (meshlink_node_t *)n, data, len) ? (ssize_t)len : -1;
 }
 
 void meshlink_set_channel_receive_cb(meshlink_handle_t *mesh, meshlink_channel_t *channel, meshlink_channel_receive_cb_t cb) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_channel_receive_cb(%p, %p)", (void *)channel, (void *)(intptr_t)cb);
+
 	if(!mesh || !channel) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
@@ -3545,7 +4075,7 @@ void meshlink_set_channel_receive_cb(meshlink_handle_t *mesh, meshlink_channel_t
 	channel->receive_cb = cb;
 }
 
-static void channel_receive(meshlink_handle_t *mesh, meshlink_node_t *source, const void *data, size_t len) {
+void channel_receive(meshlink_handle_t *mesh, meshlink_node_t *source, const void *data, size_t len) {
 	(void)mesh;
 	node_t *n = (node_t *)source;
 
@@ -3565,84 +4095,146 @@ 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);
 	}
 }
 
 void meshlink_set_channel_poll_cb(meshlink_handle_t *mesh, meshlink_channel_t *channel, meshlink_channel_poll_cb_t cb) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_channel_poll_cb(%p, %p)", (void *)channel, (void *)(intptr_t)cb);
+
 	if(!mesh || !channel) {
 		meshlink_errno = MESHLINK_EINVAL;
 		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) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_channel_listen_cb(%p)", (void *)(intptr_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) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_channel_accept_cb(%p)", (void *)(intptr_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;
 
 	for splay_each(node_t, n, mesh->nodes) {
 		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);
 		}
 	}
 
@@ -3650,32 +4242,68 @@ void meshlink_set_channel_accept_cb(meshlink_handle_t *mesh, meshlink_channel_ac
 }
 
 void meshlink_set_channel_sndbuf(meshlink_handle_t *mesh, meshlink_channel_t *channel, size_t size) {
-	(void)mesh;
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_channel_sndbuf(%p, %zu)", (void *)channel, size);
 
-	if(!channel) {
+	meshlink_set_channel_sndbuf_storage(mesh, channel, NULL, size);
+}
+
+void meshlink_set_channel_rcvbuf(meshlink_handle_t *mesh, meshlink_channel_t *channel, size_t size) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_channel_rcvbuf(%p, %zu)", (void *)channel, size);
+
+	meshlink_set_channel_rcvbuf_storage(mesh, channel, NULL, size);
+}
+
+void meshlink_set_channel_sndbuf_storage(meshlink_handle_t *mesh, meshlink_channel_t *channel, void *buf, size_t size) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_channel_sndbuf_storage(%p, %p, %zu)", (void *)channel, buf, size);
+
+	if(!mesh || !channel) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
-	utcp_set_sndbuf(channel->c, size);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
+	utcp_set_sndbuf(channel->c, buf, size);
 	pthread_mutex_unlock(&mesh->mutex);
 }
 
-void meshlink_set_channel_rcvbuf(meshlink_handle_t *mesh, meshlink_channel_t *channel, size_t size) {
-	(void)mesh;
+void meshlink_set_channel_rcvbuf_storage(meshlink_handle_t *mesh, meshlink_channel_t *channel, void *buf, size_t size) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_channel_rcvbuf_storage(%p, %p, %zu)", (void *)channel, buf, size);
 
-	if(!channel) {
+	if(!mesh || !channel) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return;
+	}
+
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
+	utcp_set_rcvbuf(channel->c, buf, size);
+	pthread_mutex_unlock(&mesh->mutex);
+}
+
+void meshlink_set_channel_flags(meshlink_handle_t *mesh, meshlink_channel_t *channel, uint32_t flags) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_channel_flags(%p, %u)", (void *)channel, flags);
+
+	if(!mesh || !channel) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
-	utcp_set_rcvbuf(channel->c, size);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
+	utcp_set_flags(channel->c, flags);
 	pthread_mutex_unlock(&mesh->mutex);
 }
 
 meshlink_channel_t *meshlink_channel_open_ex(meshlink_handle_t *mesh, meshlink_node_t *node, uint16_t port, meshlink_channel_receive_cb_t cb, const void *data, size_t len, uint32_t flags) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_channel_open_ex(%s, %u, %p, %p, %zu, %u)", node ? node->name : "(null)", port, (void *)(intptr_t)cb, data, len, flags);
+
 	if(data && len) {
 		abort();        // TODO: handle non-NULL data
 	}
@@ -3685,13 +4313,16 @@ 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);
-		mesh->receive_cb = channel_receive;
+		utcp_set_mtu(n->utcp, n->mtu - sizeof(meshlink_packethdr_t));
+		utcp_set_retransmit_cb(n->utcp, channel_retransmit);
 
 		if(!n->utcp) {
 			meshlink_errno = errno == ENOMEM ? MESHLINK_ENOMEM : MESHLINK_EINTERNAL;
@@ -3729,49 +4360,86 @@ meshlink_channel_t *meshlink_channel_open_ex(meshlink_handle_t *mesh, meshlink_n
 }
 
 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) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_channel_open_ex(%s, %u, %p, %p, %zu)", node ? node->name : "(null)", port, (void *)(intptr_t)cb, data, len);
+
 	return meshlink_channel_open_ex(mesh, node, port, cb, data, len, MESHLINK_CHANNEL_TCP);
 }
 
 void meshlink_channel_shutdown(meshlink_handle_t *mesh, meshlink_channel_t *channel, int direction) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_channel_shutdown(%p, %d)", (void *)channel, direction);
+
 	if(!mesh || !channel) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
 	utcp_shutdown(channel->c, direction);
 	pthread_mutex_unlock(&mesh->mutex);
 }
 
 void meshlink_channel_close(meshlink_handle_t *mesh, meshlink_channel_t *channel) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_channel_close(%p)", (void *)channel);
+
 	if(!mesh || !channel) {
 		meshlink_errno = MESHLINK_EINVAL;
 		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);
+}
+
+void meshlink_channel_abort(meshlink_handle_t *mesh, meshlink_channel_t *channel) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_channel_abort(%p)", (void *)channel);
 
-	free(channel);
+	if(!mesh || !channel) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return;
+	}
+
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
+	if(channel->c) {
+		utcp_abort(channel->c);
+		channel->c = NULL;
+
+		/* Clean up any outstanding AIO buffers. */
+		aio_abort(mesh, channel, &channel->aio_send);
+		aio_abort(mesh, channel, &channel->aio_receive);
+	}
+
+	if(!channel->in_callback) {
+		free(channel);
+	}
+
+	pthread_mutex_unlock(&mesh->mutex);
 }
 
 ssize_t meshlink_channel_send(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_channel_send(%p, %p, %zu)", (void *)channel, data, len);
+
 	if(!mesh || !channel) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return -1;
@@ -3793,7 +4461,9 @@ 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) {
@@ -3812,6 +4482,8 @@ ssize_t meshlink_channel_send(meshlink_handle_t *mesh, meshlink_channel_t *chann
 }
 
 bool meshlink_channel_aio_send(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len, meshlink_aio_cb_t cb, void *priv) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_channel_aio_send(%p, %p, %zu, %p, %p)", (void *)channel, data, len, (void *)(intptr_t)cb, priv);
+
 	if(!mesh || !channel) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
@@ -3828,7 +4500,9 @@ 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;
@@ -3841,7 +4515,11 @@ 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_sndbuf_free(channel->c));
+
+	if(todo) {
+		channel_poll(channel->c, todo);
+	}
 
 	pthread_mutex_unlock(&mesh->mutex);
 
@@ -3849,6 +4527,8 @@ bool meshlink_channel_aio_send(meshlink_handle_t *mesh, meshlink_channel_t *chan
 }
 
 bool meshlink_channel_aio_fd_send(meshlink_handle_t *mesh, meshlink_channel_t *channel, int fd, size_t len, meshlink_aio_fd_cb_t cb, void *priv) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_channel_aio_fd_send(%p, %d, %zu, %p, %p)", (void *)channel, fd, len, (void *)(intptr_t)cb, priv);
+
 	if(!mesh || !channel) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
@@ -3865,7 +4545,9 @@ 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;
@@ -3878,7 +4560,11 @@ 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_sndbuf_free(channel->c);
+
+	if(left) {
+		channel_poll(channel->c, left);
+	}
 
 	pthread_mutex_unlock(&mesh->mutex);
 
@@ -3886,6 +4572,8 @@ bool meshlink_channel_aio_fd_send(meshlink_handle_t *mesh, meshlink_channel_t *c
 }
 
 bool meshlink_channel_aio_receive(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len, meshlink_aio_cb_t cb, void *priv) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_channel_aio_receive(%p, %p, %zu, %p, %p)", (void *)channel, data, len, (void *)(intptr_t)cb, priv);
+
 	if(!mesh || !channel) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
@@ -3902,7 +4590,9 @@ 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;
@@ -3919,6 +4609,8 @@ bool meshlink_channel_aio_receive(meshlink_handle_t *mesh, meshlink_channel_t *c
 }
 
 bool meshlink_channel_aio_fd_receive(meshlink_handle_t *mesh, meshlink_channel_t *channel, int fd, size_t len, meshlink_aio_fd_cb_t cb, void *priv) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_channel_aio_fd_receive(%p, %d, %zu, %p, %p)", (void *)channel, fd, len, (void *)(intptr_t)cb, priv);
+
 	if(!mesh || !channel) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return false;
@@ -3935,7 +4627,9 @@ 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;
@@ -3978,7 +4672,18 @@ size_t meshlink_channel_get_recvq(meshlink_handle_t *mesh, meshlink_channel_t *c
 	return utcp_get_recvq(channel->c);
 }
 
+size_t meshlink_channel_get_mss(meshlink_handle_t *mesh, meshlink_channel_t *channel) {
+	if(!mesh || !channel) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return -1;
+	}
+
+	return utcp_get_mss(channel->node->utcp);
+}
+
 void meshlink_set_node_channel_timeout(meshlink_handle_t *mesh, meshlink_node_t *node, int timeout) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_node_channel_timeout(%s, %d)", node ? node->name : "(null)", timeout);
+
 	if(!mesh || !node) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
@@ -3986,10 +4691,14 @@ 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);
@@ -4000,6 +4709,8 @@ void meshlink_set_node_channel_timeout(meshlink_handle_t *mesh, meshlink_node_t
 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) {
@@ -4012,6 +4723,8 @@ void update_node_status(meshlink_handle_t *mesh, node_t *n) {
 }
 
 void update_node_pmtu(meshlink_handle_t *mesh, node_t *n) {
+	utcp_set_mtu(n->utcp, (n->minmtu > MINMTU ? n->minmtu : MINMTU) - sizeof(meshlink_packethdr_t));
+
 	if(mesh->node_pmtu_cb && !n->status.blacklisted) {
 		mesh->node_pmtu_cb(mesh, (meshlink_node_t *)n, n->minmtu);
 	}
@@ -4027,16 +4740,18 @@ void handle_duplicate_node(meshlink_handle_t *mesh, node_t *n) {
 }
 
 void meshlink_enable_discovery(meshlink_handle_t *mesh, bool enable) {
-#if HAVE_CATTA
+	logger(mesh, MESHLINK_DEBUG, "meshlink_enable_discovery(%d)", enable);
 
 	if(!mesh) {
 		meshlink_errno = MESHLINK_EINVAL;
 		return;
 	}
 
-	pthread_mutex_lock(&mesh->mutex);
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
 
-	if(mesh->discovery == enable) {
+	if(mesh->discovery.enabled == enable) {
 		goto end;
 	}
 
@@ -4048,18 +4763,39 @@ void meshlink_enable_discovery(meshlink_handle_t *mesh, bool enable) {
 		}
 	}
 
-	mesh->discovery = enable;
+	mesh->discovery.enabled = enable;
 
 end:
 	pthread_mutex_unlock(&mesh->mutex);
-#else
-	(void)mesh;
-	(void)enable;
-	meshlink_errno = MESHLINK_ENOTSUP;
-#endif
+}
+
+void meshlink_hint_network_change(struct meshlink_handle *mesh) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_hint_network_change()");
+
+	if(!mesh) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return;
+	}
+
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
+	if(mesh->discovery.enabled) {
+		scan_ifaddrs(mesh);
+	}
+
+	if(mesh->loop.now.tv_sec > mesh->discovery.last_update + 5) {
+		mesh->discovery.last_update = mesh->loop.now.tv_sec;
+		handle_network_change(mesh, 1);
+	}
+
+	pthread_mutex_unlock(&mesh->mutex);
 }
 
 void meshlink_set_dev_class_timeouts(meshlink_handle_t *mesh, dev_class_t devclass, int pinginterval, int pingtimeout) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_dev_class_timeouts(%d, %d, %d)", devclass, pinginterval, pingtimeout);
+
 	if(!mesh || devclass < 0 || devclass >= DEV_CLASS_COUNT) {
 		meshlink_errno = EINVAL;
 		return;
@@ -4070,13 +4806,18 @@ 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);
 }
 
 void meshlink_set_dev_class_fast_retry_period(meshlink_handle_t *mesh, dev_class_t devclass, int fast_retry_period) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_dev_class_fast_retry_period(%d, %d)", devclass, fast_retry_period);
+
 	if(!mesh || devclass < 0 || devclass >= DEV_CLASS_COUNT) {
 		meshlink_errno = EINVAL;
 		return;
@@ -4087,23 +4828,74 @@ 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) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_dev_class_fast_maxtimeout(%d, %d)", devclass, 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) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_reset_timers()");
+
+	if(!mesh) {
+		return;
+	}
+
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
+	handle_network_change(mesh, true);
+
+	if(mesh->discovery.enabled) {
+		discovery_refresh(mesh);
+	}
+
+	pthread_mutex_unlock(&mesh->mutex);
+}
+
+void meshlink_set_inviter_commits_first(struct meshlink_handle *mesh, bool inviter_commits_first) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_inviter_commits_first(%d)", 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);
 }
 
 void meshlink_set_external_address_discovery_url(struct meshlink_handle *mesh, const char *url) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_external_address_discovery_url(%s)", url ? url : "(null)");
+
 	if(!mesh) {
 		meshlink_errno = EINVAL;
 		return;
@@ -4114,12 +4906,42 @@ 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);
 }
 
+void meshlink_set_scheduling_granularity(struct meshlink_handle *mesh, long granularity) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_scheduling_granularity(%ld)", granularity);
+
+	if(!mesh || granularity < 0) {
+		meshlink_errno = EINVAL;
+		return;
+	}
+
+	utcp_set_clock_granularity(granularity);
+}
+
+void meshlink_set_storage_policy(struct meshlink_handle *mesh, meshlink_storage_policy_t policy) {
+	logger(mesh, MESHLINK_DEBUG, "meshlink_set_storage_policy(%d)", policy);
+
+	if(!mesh) {
+		meshlink_errno = EINVAL;
+		return;
+	}
+
+	if(pthread_mutex_lock(&mesh->mutex) != 0) {
+		abort();
+	}
+
+	mesh->storage_policy = policy;
+	pthread_mutex_unlock(&mesh->mutex);
+}
+
 void handle_network_change(meshlink_handle_t *mesh, bool online) {
 	(void)online;
 
@@ -4128,9 +4950,10 @@ 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;
@@ -4141,12 +4964,13 @@ 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);
 	}
 }
 
 static void __attribute__((constructor)) meshlink_init(void) {
 	crypto_init();
+	utcp_set_clock_granularity(10000);
 }
 
 static void __attribute__((destructor)) meshlink_exit(void) {