X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Fmeshlink.c;h=f9e7e9054d291c308b6987a6d4460794e6c030f7;hb=efbdf1564bb6a8f17ca28e61ccc6a507f1159994;hp=e5982721d533aadd2cafb8e775f6dcb7b1555916;hpb=1191935b499d91859e9ac74919f3ab28ddf62d3e;p=meshlink

diff --git a/src/meshlink.c b/src/meshlink.c
index e5982721..f9e7e905 100644
--- a/src/meshlink.c
+++ b/src/meshlink.c
@@ -16,7 +16,7 @@
     with this program; if not, write to the Free Software Foundation, Inc.,
     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
-#define VAR_SERVER 1    /* Should be in tinc.conf */
+#define VAR_SERVER 1    /* Should be in meshlink.conf */
 #define VAR_HOST 2      /* Can be in host config file */
 #define VAR_MULTIPLE 4  /* Multiple statements allowed */
 #define VAR_OBSOLETE 8  /* Should not be used anymore */
@@ -39,11 +39,14 @@ typedef struct {
 #include "utils.h"
 #include "xalloc.h"
 #include "ed25519/sha512.h"
+#include "discovery.h"
 
 #ifndef MSG_NOSIGNAL
 #define MSG_NOSIGNAL 0
 #endif
 
+__thread meshlink_errno_t meshlink_errno;
+
 //TODO: this can go away completely
 const var_t variables[] = {
 	/* Server configuration */
@@ -190,9 +193,9 @@ static char *get_my_hostname(meshlink_handle_t* mesh) {
 
 	// If that doesn't work, guess externally visible hostname
 	fprintf(stderr, "Trying to discover externally visible hostname...\n");
-	struct addrinfo *ai = str2addrinfo("tinc-vpn.org", "80", SOCK_STREAM);
+	struct addrinfo *ai = str2addrinfo("meshlink.io", "80", SOCK_STREAM);
 	struct addrinfo *aip = ai;
-	static const char request[] = "GET http://tinc-vpn.org/host.cgi HTTP/1.0\r\n\r\n";
+	static const char request[] = "GET http://www.meshlink.io/host.cgi HTTP/1.0\r\n\r\n";
 
 	while(aip) {
 		int s = socket(aip->ai_family, aip->ai_socktype, aip->ai_protocol);
@@ -327,15 +330,20 @@ static bool try_bind(int port) {
 
 	while(ai) {
 		int fd = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
-		if(!fd)
+		if(!fd) {
+			freeaddrinfo(ai);
 			return false;
+		}
 		int result = bind(fd, ai->ai_addr, ai->ai_addrlen);
 		closesocket(fd);
-		if(result)
+		if(result) {
+			freeaddrinfo(ai);
 			return false;
+		}
 		ai = ai->ai_next;
 	}
 
+	freeaddrinfo(ai);
 	return true;
 }
 
@@ -398,7 +406,7 @@ static bool finalize_join(meshlink_handle_t *mesh) {
 		return false;
 	}
 
-	// Filter first chunk on approved keywords, split between tinc.conf and hosts/Name
+	// Filter first chunk on approved keywords, split between meshlink.conf and hosts/Name
 	// Other chunks go unfiltered to their respective host config files
 	const char *p = mesh->data;
 	char *l, *value;
@@ -508,7 +516,7 @@ static bool finalize_join(meshlink_handle_t *mesh) {
 	free(mesh->self->name);
 	free(mesh->self->connection->name);
 	mesh->self->name = xstrdup(name);
-	mesh->self->connection->name = xstrdup(name);
+	mesh->self->connection->name = name;
 
 	fprintf(stderr, "Configuration stored in: %s\n", mesh->confbase);
 
@@ -618,12 +626,21 @@ static bool sendline(int fd, char *format, ...) {
 
 static const char *errstr[] = {
 	[MESHLINK_OK] = "No error",
+	[MESHLINK_EINVAL] = "Invalid argument",
 	[MESHLINK_ENOMEM] = "Out of memory",
 	[MESHLINK_ENOENT] = "No such node",
+	[MESHLINK_EEXIST] = "Node already exists",
+	[MESHLINK_EINTERNAL] = "Internal error",
+	[MESHLINK_ERESOLV] = "Could not resolve hostname",
+	[MESHLINK_ESTORAGE] = "Storage error",
+	[MESHLINK_ENETWORK] = "Network error",
+	[MESHLINK_EPEER] = "Error communicating with peer",
 };
 
-const char *meshlink_strerror(meshlink_errno_t errno) {
-	return errstr[errno];
+const char *meshlink_strerror(meshlink_errno_t err) {
+	if(err < 0 || err >= sizeof errstr / sizeof *errstr)
+		return "Invalid error code";
+	return errstr[err];
 }
 
 static bool ecdsa_keygen(meshlink_handle_t *mesh) {
@@ -635,6 +652,7 @@ static bool ecdsa_keygen(meshlink_handle_t *mesh) {
 
 	if(!(key = ecdsa_generate())) {
 		fprintf(stderr, "Error during key generation!\n");
+		meshlink_errno = MESHLINK_EINTERNAL;
 		return false;
 	} else
 		fprintf(stderr, "Done.\n");
@@ -642,8 +660,10 @@ static bool ecdsa_keygen(meshlink_handle_t *mesh) {
 	snprintf(privname, sizeof privname, "%s" SLASH "ecdsa_key.priv", mesh->confbase);
 	f = fopen(privname, "w");
 
-	if(!f)
+	if(!f) {
+		meshlink_errno = MESHLINK_ESTORAGE;
 		return false;
+	}
 
 #ifdef HAVE_FCHMOD
 	fchmod(fileno(f), 0600);
@@ -653,17 +673,19 @@ static bool ecdsa_keygen(meshlink_handle_t *mesh) {
 		fprintf(stderr, "Error writing private key!\n");
 		ecdsa_free(key);
 		fclose(f);
+		meshlink_errno = MESHLINK_EINTERNAL;
 		return false;
 	}
 
 	fclose(f);
 
-
 	snprintf(pubname, sizeof pubname, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, mesh->name);
 	f = fopen(pubname, "a");
 
-	if(!f)
+	if(!f) {
+		meshlink_errno = MESHLINK_ESTORAGE;
 		return false;
+	}
 
 	char *pubkey = ecdsa_get_base64_public_key(key);
 	fprintf(f, "ECDSAPublicKey = %s\n", pubkey);
@@ -678,6 +700,7 @@ static bool ecdsa_keygen(meshlink_handle_t *mesh) {
 static bool meshlink_setup(meshlink_handle_t *mesh) {
 	if(mkdir(mesh->confbase, 0777) && errno != EEXIST) {
 		fprintf(stderr, "Could not create directory %s: %s\n", mesh->confbase, strerror(errno));
+		meshlink_errno = MESHLINK_ESTORAGE;
 		return false;
 	}
 
@@ -686,6 +709,7 @@ static bool meshlink_setup(meshlink_handle_t *mesh) {
 
 	if(mkdir(filename, 0777) && errno != EEXIST) {
 		fprintf(stderr, "Could not create directory %s: %s\n", filename, strerror(errno));
+		meshlink_errno = MESHLINK_ESTORAGE;
 		return false;
 	}
 
@@ -693,20 +717,24 @@ static bool meshlink_setup(meshlink_handle_t *mesh) {
 
 	if(!access(filename, F_OK)) {
 		fprintf(stderr, "Configuration file %s already exists!\n", filename);
+		meshlink_errno = MESHLINK_EEXIST;
 		return false;
 	}
 
 	FILE *f = fopen(filename, "w");
 	if(!f) {
 		fprintf(stderr, "Could not create file %s: %s\n", filename, strerror(errno));
-		return 1;
+		meshlink_errno = MESHLINK_ESTORAGE;
+		return false;
 	}
 
 	fprintf(f, "Name = %s\n", mesh->name);
 	fclose(f);
 
-	if(!ecdsa_keygen(mesh))
+	if(!ecdsa_keygen(mesh)) {
+		meshlink_errno = MESHLINK_EINTERNAL;
 		return false;
+	}
 
 	check_port(mesh);
 
@@ -719,6 +747,7 @@ meshlink_handle_t *meshlink_open(const char *confbase, const char *name) {
 
 	if(!confbase || !*confbase) {
 		fprintf(stderr, "No confbase given!\n");
+		meshlink_errno = MESHLINK_EINVAL;
 		return NULL;
 	}
 
@@ -730,6 +759,7 @@ meshlink_handle_t *meshlink_open(const char *confbase, const char *name) {
 
 		if(!check_id(name)) {
 			fprintf(stderr, "Invalid name given!\n");
+			meshlink_errno = MESHLINK_EINVAL;
 			return NULL;
 		} else { usingname = true;}
 	}
@@ -754,10 +784,15 @@ meshlink_handle_t *meshlink_open(const char *confbase, const char *name) {
 	if(access(filename, R_OK)) {
 		if(errno == ENOENT) {
 			// If not, create it
-			meshlink_setup(mesh);
+			if(!meshlink_setup(mesh)) {
+				// meshlink_errno is set by meshlink_setup()
+				return NULL;
+			}
 		} else {
 			fprintf(stderr, "Cannot not read from %s: %s\n", filename, strerror(errno));
-			return meshlink_close(mesh), NULL;
+			meshlink_close(mesh);
+			meshlink_errno = MESHLINK_ESTORAGE;
+			return NULL;
 		}
 	}
 
@@ -765,8 +800,11 @@ meshlink_handle_t *meshlink_open(const char *confbase, const char *name) {
 
 	init_configuration(&mesh->config);
 
-	if(!read_server_config(mesh))
-		return meshlink_close(mesh), NULL;
+	if(!read_server_config(mesh)) {
+		meshlink_close(mesh);
+		meshlink_errno = MESHLINK_ESTORAGE;
+		return NULL;
+	};
 
 #ifdef HAVE_MINGW
 	struct WSAData wsa_state;
@@ -776,13 +814,16 @@ meshlink_handle_t *meshlink_open(const char *confbase, const char *name) {
 	// Setup up everything
 	// TODO: we should not open listening sockets yet
 
-	if(!setup_network(mesh))
-		return meshlink_close(mesh), NULL;
+	if(!setup_network(mesh)) {
+		meshlink_close(mesh);
+		meshlink_errno = MESHLINK_ENETWORK;
+		return NULL;
+	}
 
 	return mesh;
 }
 
-void *meshlink_main_loop(void *arg) {
+static void *meshlink_main_loop(void *arg) {
 	meshlink_handle_t *mesh = arg;
 
 	try_outgoing_connections(mesh);
@@ -793,11 +834,17 @@ void *meshlink_main_loop(void *arg) {
 }
 
 bool meshlink_start(meshlink_handle_t *mesh) {
+	if(!mesh) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
 	// TODO: open listening sockets first
 
 	//Check that a valid name is set
 	if(!mesh->name ) {
 		fprintf(stderr, "No name given!\n");
+		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
 
@@ -806,15 +853,28 @@ bool meshlink_start(meshlink_handle_t *mesh) {
 	if(pthread_create(&mesh->thread, NULL, meshlink_main_loop, mesh) != 0) {
 		fprintf(stderr, "Could not start thread: %s\n", strerror(errno));
 		memset(&mesh->thread, 0, sizeof mesh->thread);
+		meshlink_errno = MESHLINK_EINTERNAL;
 		return false;
 	}
 
 	mesh->threadstarted=true;
 
+	// Start discovery
+	if(!discovery_start(mesh))
+		return false;
+
 	return true;
 }
 
 void meshlink_stop(meshlink_handle_t *mesh) {
+	if(!mesh) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return;
+	}
+
+	// Stop discovery
+	discovery_stop(mesh);
+
 	// Shut down the listening sockets to signal the main thread to shut down
 
 	for(int i = 0; i < mesh->listen_sockets; i++) {
@@ -828,6 +888,11 @@ void meshlink_stop(meshlink_handle_t *mesh) {
 }
 
 void meshlink_close(meshlink_handle_t *mesh) {
+	if(!mesh || !mesh->confbase) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return;
+	}
+
 	// Close and free all resources used.
 
 	close_network_connections(mesh);
@@ -837,27 +902,62 @@ void meshlink_close(meshlink_handle_t *mesh) {
 	exit_configuration(&mesh->config);
 	event_loop_exit(&mesh->loop);
 
-	free(mesh);
-
 #ifdef HAVE_MINGW
-	WSACleanup();
+	if(mesh->confbase)
+		WSACleanup();
 #endif
+
+	ecdsa_free(mesh->invitation_key);
+
+	free(mesh->name);
+	free(mesh->confbase);
+
+	memset(mesh, 0, sizeof *mesh);
+
+	free(mesh);
 }
 
 void meshlink_set_receive_cb(meshlink_handle_t *mesh, meshlink_receive_cb_t cb) {
+	if(!mesh) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return;
+	}
+
 	mesh->receive_cb = cb;
 }
 
 void meshlink_set_node_status_cb(meshlink_handle_t *mesh, meshlink_node_status_cb_t cb) {
+	if(!mesh) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return;
+	}
+
 	mesh->node_status_cb = cb;
 }
 
 void meshlink_set_log_cb(meshlink_handle_t *mesh, meshlink_log_level_t level, meshlink_log_cb_t cb) {
+	if(!mesh) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return;
+	}
+
 	mesh->log_cb = cb;
 	mesh->log_level = level;
 }
 
-bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const void *data, unsigned int len) {
+bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const void *data, size_t len) {
+	if(!mesh || !destination) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
+	if(!len)
+		return true;
+
+	if(!data) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
 
 	/* If there is no outgoing list yet, create one. */
 
@@ -906,33 +1006,119 @@ void meshlink_send_from_queue(event_loop_t* el,meshlink_handle_t *mesh) {
 	return ;
 }
 
+ssize_t meshlink_get_pmtu(meshlink_handle_t *mesh, meshlink_node_t *destination) {
+	if(!mesh || !destination) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return -1;
+	}
+
+	node_t *n = (node_t *)destination;
+	if(!n->status.reachable)
+		return 0;
+	else if(n->mtuprobes > 30 && n->minmtu)
+		return n->minmtu;
+	else
+		return MTU;
+}
+
+char *meshlink_get_fingerprint(meshlink_handle_t *mesh, meshlink_node_t *node) {
+	if(!mesh || !node) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
+
+	node_t *n = (node_t *)node;
+
+	if(!node_read_ecdsa_public_key(mesh, n) || !n->ecdsa) {
+		meshlink_errno = MESHLINK_EINTERNAL;
+		return false;
+	}
+
+	char *fingerprint = ecdsa_get_base64_public_key(n->ecdsa);
+
+	if(!fingerprint)
+		meshlink_errno = MESHLINK_EINTERNAL;
+
+	return fingerprint;
+}
+
 meshlink_node_t *meshlink_get_node(meshlink_handle_t *mesh, const char *name) {
+	if(!mesh || !name) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
+
 	return (meshlink_node_t *)lookup_node(mesh, (char *)name); // TODO: make lookup_node() use const
 }
 
-size_t meshlink_get_all_nodes(meshlink_handle_t *mesh, meshlink_node_t **nodes, size_t nmemb) {
-	size_t i = 0;
+meshlink_node_t **meshlink_get_all_nodes(meshlink_handle_t *mesh, meshlink_node_t **nodes, size_t *nmemb) {
+	if(!mesh || !nmemb || (*nmemb && !nodes)) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
+
+	meshlink_node_t **result;
 
 	//lock mesh->nodes
 	pthread_mutex_lock(&(mesh->nodes_mutex));
 
-	for splay_each(node_t, n, mesh->nodes) {
-		if(i < nmemb)
-			nodes[i] = (meshlink_node_t *)n;
-		i++;
+	*nmemb = mesh->nodes->count;
+	result = realloc(nodes, *nmemb * sizeof *nodes);
+
+	if(result) {
+		meshlink_node_t **p = result;
+		for splay_each(node_t, n, mesh->nodes)
+			*p++ = (meshlink_node_t *)n;
+	} else {
+		*nmemb = 0;
+		free(nodes);
+		meshlink_errno = MESHLINK_ENOMEM;
 	}
 
 	pthread_mutex_unlock(&(mesh->nodes_mutex));
 
-	return i;
+	return result;
 }
 
-char *meshlink_sign(meshlink_handle_t *mesh, const char *data, size_t len) {
-	return NULL;
+bool meshlink_sign(meshlink_handle_t *mesh, const void *data, size_t len, void *signature, size_t *siglen) {
+	if(!mesh || !data || !len || !signature || !siglen) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
+	if(*siglen < MESHLINK_SIGLEN) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
+	if(!ecdsa_sign(mesh->self->connection->ecdsa, data, len, signature)) {
+		meshlink_errno = MESHLINK_EINTERNAL;
+		return false;
+	}
+
+	*siglen = MESHLINK_SIGLEN;
+	return true;
 }
 
-bool meshlink_verify(meshlink_handle_t *mesh, meshlink_node_t *source, const char *data, size_t len, const char *signature) {
-	return false;
+bool meshlink_verify(meshlink_handle_t *mesh, meshlink_node_t *source, const void *data, size_t len, const void *signature, size_t siglen) {
+	if(!mesh || !data || !len || !signature) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
+	if(siglen != MESHLINK_SIGLEN) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
+	struct node_t *n = (struct node_t *)source;
+	node_read_ecdsa_public_key(mesh, n);
+	if(!n->ecdsa) {
+		meshlink_errno = MESHLINK_EINTERNAL;
+		return false;
+	}
+
+	return ecdsa_verify(((struct node_t *)source)->ecdsa, data, len, signature);
 }
 
 static bool refresh_invitation_key(meshlink_handle_t *mesh) {
@@ -941,6 +1127,7 @@ static bool refresh_invitation_key(meshlink_handle_t *mesh) {
 	snprintf(filename, sizeof filename, "%s" SLASH "invitations", mesh->confbase);
 	if(mkdir(filename, 0700) && errno != EEXIST) {
 		fprintf(stderr, "Could not create directory %s: %s\n", filename, strerror(errno));
+		meshlink_errno = MESHLINK_ESTORAGE;
 		return false;
 	}
 
@@ -948,6 +1135,7 @@ static bool refresh_invitation_key(meshlink_handle_t *mesh) {
 	DIR *dir = opendir(filename);
 	if(!dir) {
 		fprintf(stderr, "Could not read directory %s: %s\n", filename, strerror(errno));
+		meshlink_errno = MESHLINK_ESTORAGE;
 		return false;
 	}
 
@@ -976,6 +1164,7 @@ static bool refresh_invitation_key(meshlink_handle_t *mesh) {
 	if(errno) {
 		fprintf(stderr, "Error while reading directory %s: %s\n", filename, strerror(errno));
 		closedir(dir);
+		meshlink_errno = MESHLINK_ESTORAGE;
 		return false;
 	}
 
@@ -1000,17 +1189,20 @@ static bool refresh_invitation_key(meshlink_handle_t *mesh) {
 	if(!f) {
 		if(errno != ENOENT) {
 			fprintf(stderr, "Could not read %s: %s\n", filename, strerror(errno));
+			meshlink_errno = MESHLINK_ESTORAGE;
 			return false;
 		}
 
 		mesh->invitation_key = ecdsa_generate();
 		if(!mesh->invitation_key) {
 			fprintf(stderr, "Could not generate a new key!\n");
+			meshlink_errno = MESHLINK_EINTERNAL;
 			return false;
 		}
 		f = fopen(filename, "w");
 		if(!f) {
 			fprintf(stderr, "Could not write %s: %s\n", filename, strerror(errno));
+			meshlink_errno = MESHLINK_ESTORAGE;
 			return false;
 		}
 		chmod(filename, 0600);
@@ -1019,18 +1211,26 @@ static bool refresh_invitation_key(meshlink_handle_t *mesh) {
 	} else {
 		mesh->invitation_key = ecdsa_read_pem_private_key(f);
 		fclose(f);
-		if(!mesh->invitation_key)
+		if(!mesh->invitation_key) {
 			fprintf(stderr, "Could not read private key from %s\n", filename);
+			meshlink_errno = MESHLINK_ESTORAGE;
+		}
 	}
 
 	return mesh->invitation_key;
 }
 
 bool meshlink_add_address(meshlink_handle_t *mesh, const char *address) {
+	if(!mesh || !address) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
 	for(const char *p = address; *p; p++) {
 		if(isalnum(*p) || *p == '-' || *p == '.' || *p == ':')
 			continue;
 		fprintf(stderr, "Invalid character in address: %s\n", address);
+		meshlink_errno = MESHLINK_EINVAL;
 		return false;
 	}
 
@@ -1038,9 +1238,15 @@ bool meshlink_add_address(meshlink_handle_t *mesh, const char *address) {
 }
 
 char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
+	if(!mesh) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
+
 	// Check validity of the new node's name
 	if(!check_id(name)) {
 		fprintf(stderr, "Invalid name for node.\n");
+		meshlink_errno = MESHLINK_EINVAL;
 		return NULL;
 	}
 
@@ -1049,12 +1255,14 @@ char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
 	snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, name);
 	if(!access(filename, F_OK)) {
 		fprintf(stderr, "A host config file for %s already exists!\n", name);
+		meshlink_errno = MESHLINK_EEXIST;
 		return NULL;
 	}
 
 	// Ensure no other nodes know about this name
 	if(meshlink_get_node(mesh, name)) {
 		fprintf(stderr, "A node with name %s is already known!\n", name);
+		meshlink_errno = MESHLINK_EEXIST;
 		return NULL;
 	}
 
@@ -1062,11 +1270,14 @@ char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
 	char *address = get_my_hostname(mesh);
 	if(!address) {
 		fprintf(stderr, "No Address known for ourselves!\n");
+		meshlink_errno = MESHLINK_ERESOLV;
 		return NULL;
 	}
 
-	if(!refresh_invitation_key(mesh))
+	if(!refresh_invitation_key(mesh)) {
+		meshlink_errno = MESHLINK_EINTERNAL;
 		return NULL;
+	}
 
 	char hash[64];
 
@@ -1089,11 +1300,14 @@ char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
 
 	b64encode_urlsafe(cookie, cookie, 18);
 
+	free(fingerprint);
+
 	// Create a file containing the details of the invitation.
 	snprintf(filename, sizeof filename, "%s" SLASH "invitations" SLASH "%s", mesh->confbase, cookiehash);
 	int ifd = open(filename, O_RDWR | O_CREAT | O_EXCL, 0600);
 	if(!ifd) {
 		fprintf(stderr, "Could not create invitation file %s: %s\n", filename, strerror(errno));
+		meshlink_errno = MESHLINK_ESTORAGE;
 		return NULL;
 	}
 	FILE *f = fdopen(ifd, "w");
@@ -1123,6 +1337,7 @@ char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
 		fclose(tc);
 	} else {
 		fprintf(stderr, "Could not create %s: %s\n", filename, strerror(errno));
+		meshlink_errno = MESHLINK_ESTORAGE;
 		return NULL;
 	}
 
@@ -1136,11 +1351,17 @@ char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
 	// Create an URL from the local address, key hash and cookie
 	char *url;
 	xasprintf(&url, "%s/%s%s", address, hash, cookie);
+	free(address);
 
 	return url;
 }
 
 bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
+	if(!mesh || !invitation) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
 	//TODO: think of a better name for this variable, or of a different way to tokenize the invitation URL.
 	char copy[strlen(invitation) + 1];
 	strcpy(copy, invitation);
@@ -1180,8 +1401,10 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 
 	// Generate a throw-away key for the invitation.
 	ecdsa_t *key = ecdsa_generate();
-	if(!key)
+	if(!key) {
+		meshlink_errno = MESHLINK_EINTERNAL;
 		return false;
+	}
 
 	char *b64key = ecdsa_get_base64_public_key(key);
 
@@ -1192,21 +1415,29 @@ 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);
-	if(!ai)
+	if(!ai) {
+		meshlink_errno = MESHLINK_ERESOLV;
 		return false;
+	}
 
 	mesh->sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
 	if(mesh->sock <= 0) {
 		fprintf(stderr, "Could not open socket: %s\n", strerror(errno));
+		freeaddrinfo(ai);
+		meshlink_errno = MESHLINK_ENETWORK;
 		return false;
 	}
 
 	if(connect(mesh->sock, ai->ai_addr, ai->ai_addrlen)) {
 		fprintf(stderr, "Could not connect to %s port %s: %s\n", address, port, strerror(errno));
 		closesocket(mesh->sock);
+		freeaddrinfo(ai);
+		meshlink_errno = MESHLINK_ENETWORK;
 		return false;
 	}
 
+	freeaddrinfo(ai);
+
 	fprintf(stderr, "Connected to %s port %s...\n", address, port);
 
 	// Tell him we have an invitation, and give him our throw-away key.
@@ -1216,15 +1447,19 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 	if(!sendline(mesh->sock, "0 ?%s %d.%d", b64key, PROT_MAJOR, 1)) {
 		fprintf(stderr, "Error sending request to %s port %s: %s\n", address, port, strerror(errno));
 		closesocket(mesh->sock);
+		meshlink_errno = MESHLINK_ENETWORK;
 		return false;
 	}
 
+	free(b64key);
+
 	char hisname[4096] = "";
 	int code, hismajor, hisminor = 0;
 
 	if(!recvline(mesh, sizeof mesh->line) || sscanf(mesh->line, "%d %s %d.%d", &code, hisname, &hismajor, &hisminor) < 3 || code != 0 || hismajor != PROT_MAJOR || !check_id(hisname) || !recvline(mesh, sizeof mesh->line) || !rstrip(mesh->line) || sscanf(mesh->line, "%d ", &code) != 1 || code != ACK || strlen(mesh->line) < 3) {
 		fprintf(stderr, "Cannot read greeting from peer\n");
 		closesocket(mesh->sock);
+		meshlink_errno = MESHLINK_ENETWORK;
 		return false;
 	}
 
@@ -1233,25 +1468,33 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 	char hishash[64];
 	if(sha512(fingerprint, strlen(fingerprint), hishash)) {
 		fprintf(stderr, "Could not create hash\n%s\n", mesh->line + 2);
+		meshlink_errno = MESHLINK_EINTERNAL;
 		return false;
 	}
 	if(memcmp(hishash, mesh->hash, 18)) {
 		fprintf(stderr, "Peer has an invalid key!\n%s\n", mesh->line + 2);
+		meshlink_errno = MESHLINK_EPEER;
 		return false;
 
 	}
 
 	ecdsa_t *hiskey = ecdsa_set_base64_public_key(fingerprint);
-	if(!hiskey)
+	if(!hiskey) {
+		meshlink_errno = MESHLINK_EINTERNAL;
 		return false;
+	}
 
 	// Start an SPTPS session
-	if(!sptps_start(&mesh->sptps, mesh, true, false, key, hiskey, "meshlink invitation", 15, invitation_send, invitation_receive))
+	if(!sptps_start(&mesh->sptps, mesh, true, false, key, hiskey, "meshlink invitation", 15, invitation_send, invitation_receive)) {
+		meshlink_errno = MESHLINK_EINTERNAL;
 		return false;
+	}
 
 	// Feed rest of input buffer to SPTPS
-	if(!sptps_receive_data(&mesh->sptps, mesh->buffer, mesh->blen))
+	if(!sptps_receive_data(&mesh->sptps, mesh->buffer, mesh->blen)) {
+		meshlink_errno = MESHLINK_EPEER;
 		return false;
+	}
 
 	int len;
 
@@ -1260,11 +1503,14 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 			if(errno == EINTR)
 				continue;
 			fprintf(stderr, "Error reading data from %s port %s: %s\n", address, port, strerror(errno));
+			meshlink_errno = MESHLINK_ENETWORK;
 			return false;
 		}
 
-		if(!sptps_receive_data(&mesh->sptps, mesh->line, len))
+		if(!sptps_receive_data(&mesh->sptps, mesh->line, len)) {
+			meshlink_errno = MESHLINK_EPEER;
 			return false;
+		}
 	}
 
 	sptps_stop(&mesh->sptps);
@@ -1274,6 +1520,7 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 
 	if(!mesh->success) {
 		fprintf(stderr, "Connection closed by peer, invitation cancelled.\n");
+		meshlink_errno = MESHLINK_EPEER;
 		return false;
 	}
 
@@ -1281,15 +1528,22 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 
 invalid:
 	fprintf(stderr, "Invalid invitation URL or you are already connected to a Mesh ?\n");
+	meshlink_errno = MESHLINK_EINVAL;
 	return false;
 }
 
 char *meshlink_export(meshlink_handle_t *mesh) {
+	if(!mesh) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
+
 	char filename[PATH_MAX];
 	snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, mesh->self->name);
 	FILE *f = fopen(filename, "r");
 	if(!f) {
 		fprintf(stderr, "Could not open %s: %s\n", filename, strerror(errno));
+		meshlink_errno = MESHLINK_ESTORAGE;
 		return NULL;
 	}
 
@@ -1303,6 +1557,7 @@ char *meshlink_export(meshlink_handle_t *mesh) {
 	if(fread(buf + len - fsize - 1, fsize, 1, f) != 1) {
 		fprintf(stderr, "Error reading from %s: %s\n", filename, strerror(errno));
 		fclose(f);
+		meshlink_errno = MESHLINK_ESTORAGE;
 		return NULL;
 	}
 
@@ -1312,14 +1567,21 @@ char *meshlink_export(meshlink_handle_t *mesh) {
 }
 
 bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
+	if(!mesh || !data) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
+
 	if(strncmp(data, "Name = ", 7)) {
 		fprintf(stderr, "Invalid data\n");
+		meshlink_errno = MESHLINK_EPEER;
 		return false;
 	}
 
 	char *end = strchr(data + 7, '\n');
 	if(!end) {
 		fprintf(stderr, "Invalid data\n");
+		meshlink_errno = MESHLINK_EPEER;
 		return false;
 	}
 
@@ -1329,6 +1591,7 @@ bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
 	name[len] = 0;
 	if(!check_id(name)) {
 		fprintf(stderr, "Invalid Name\n");
+		meshlink_errno = MESHLINK_EPEER;
 		return false;
 	}
 
@@ -1336,17 +1599,20 @@ bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
 	snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, name);
 	if(!access(filename, F_OK)) {
 		fprintf(stderr, "File %s already exists, not importing\n", filename);
+		meshlink_errno = MESHLINK_EEXIST;
 		return false;
 	}
 
 	if(errno != ENOENT) {
 		fprintf(stderr, "Error accessing %s: %s\n", filename, strerror(errno));
+		meshlink_errno = MESHLINK_ESTORAGE;
 		return false;
 	}
 
 	FILE *f = fopen(filename, "w");
 	if(!f) {
 		fprintf(stderr, "Could not create %s: %s\n", filename, strerror(errno));
+		meshlink_errno = MESHLINK_ESTORAGE;
 		return false;
 	}
 
@@ -1359,15 +1625,34 @@ bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
 }
 
 void meshlink_blacklist(meshlink_handle_t *mesh, meshlink_node_t *node) {
-    node_t *n;
-    n = (node_t*)node;
-    n->status.blacklisted=true;
+	if(!mesh || !node) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return;
+	}
+
+	node_t *n;
+	n = (node_t*)node;
+	n->status.blacklisted=true;
 	fprintf(stderr, "Blacklisted %s.\n",node->name);
 
 	//Make blacklisting persistent in the config file
 	append_config_file(mesh, n->name, "blacklisted", "yes");
-    return;
 
+	return;
+}
+
+void meshlink_whitelist(meshlink_handle_t *mesh, meshlink_node_t *node) {
+	if(!mesh || !node) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return;
+	}
+
+	node_t *n = (node_t *)node;
+	n->status.blacklisted = false;
+
+	//TODO: remove blacklisted = yes from the config file
+
+	return;
 }
 
 static void __attribute__((constructor)) meshlink_init(void) {