X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Fmeshlink.c;h=79db920b6a9d39eef024f6ee56c692679024925b;hb=97b93e51807c818c6ccd2e759e9cc380e0137b52;hp=738ab7820bee7f3ed647c45439386dea4daf76b2;hpb=c6a94a721a780c4491e145a784f85e56b4fa9f23;p=meshlink

diff --git a/src/meshlink.c b/src/meshlink.c
index 738ab782..79db920b 100644
--- a/src/meshlink.c
+++ b/src/meshlink.c
@@ -16,11 +16,13 @@
     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 */
 #define VAR_SAFE 16     /* Variable is safe when accepting invitations */
+#define MAX_ADDRESS_LENGTH 45 /* Max length of an (IPv6) address */
+#define MAX_PORT_LENGTH 5 /* 0-65535 */
 typedef struct {
 	const char *name;
 	int type;
@@ -32,12 +34,22 @@ typedef struct {
 #include "crypto.h"
 #include "ecdsagen.h"
 #include "meshlink_internal.h"
+#include "netutl.h"
 #include "node.h"
 #include "protocol.h"
 #include "route.h"
+#include "utils.h"
 #include "xalloc.h"
 #include "ed25519/sha512.h"
+#include "discovery.h"
 
+#ifndef MSG_NOSIGNAL
+#define MSG_NOSIGNAL 0
+#endif
+
+static pthread_mutex_t global_mutex;
+
+__thread meshlink_errno_t meshlink_errno;
 
 //TODO: this can go away completely
 const var_t variables[] = {
@@ -103,36 +115,6 @@ const var_t variables[] = {
 	{NULL, 0}
 };
 
-static char *get_my_name(meshlink_handle_t* mesh) {
-	FILE *f = fopen(mesh->meshlink_conf, "r");
-	if(!f) {
-		return NULL;
-	}
-
-	char buf[4096];
-	char *value;
-	while(fgets(buf, sizeof buf, f)) {
-		int len = strcspn(buf, "\t =");
-		value = buf + len;
-		value += strspn(value, "\t ");
-		if(*value == '=') {
-			value++;
-			value += strspn(value, "\t ");
-		}
-		if(!rstrip(value))
-			continue;
-		buf[len] = 0;
-		if(strcasecmp(buf, "Name"))
-			continue;
-		if(*value) {
-			fclose(f);
-			return strdup(value);
-		}
-	}
-
-	fclose(f);
-	return NULL;
-}
 static bool fcopy(FILE *out, const char *filename) {
 	FILE *in = fopen(filename, "r");
 	if(!in) {
@@ -147,6 +129,14 @@ static bool fcopy(FILE *out, const char *filename) {
 	fclose(in);
 	return true;
 }
+
+static int rstrip(char *value) {
+	int len = strlen(value);
+	while(len && strchr("\t\r\n ", value[len - 1]))
+		value[--len] = 0;
+	return len;
+}
+
 static void scan_for_hostname(const char *filename, char **hostname, char **port) {
 	char line[4096];
 	if(!filename || (*hostname && *port))
@@ -193,25 +183,23 @@ static char *get_my_hostname(meshlink_handle_t* mesh) {
 	char *hostname = NULL;
 	char *port = NULL;
 	char *hostport = NULL;
-	char *name = get_my_name(mesh);
-	char filename[PATH_MAX];
+	char *name = mesh->self->name;
+	char filename[PATH_MAX] = "";
 	char line[4096];
+	FILE *f;
 
 	// Use first Address statement in own host config file
-	if(check_id(name)) {
-		snprintf(filename,PATH_MAX, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, name);
-		scan_for_hostname(filename, &hostname, &port);
-		scan_for_hostname(mesh->meshlink_conf, &hostname, &port);
-	}
+	snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, name);
+	scan_for_hostname(filename, &hostname, &port);
 
 	if(hostname)
 		goto done;
 
 	// 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);
@@ -255,52 +243,15 @@ static char *get_my_hostname(meshlink_handle_t* mesh) {
 		}
 	}
 
-	//if(!tty) {
-	//	if(!hostname) {
-	//		fprintf(stderr, "Could not determine the external address or hostname. Please set Address manually.\n");
-	//		return NULL;
-	//	}
-	//	goto save;
-	//}
-
-again:
-	fprintf(stderr, "Please enter your host's external address or hostname");
-	if(hostname)
-		fprintf(stderr, " [%s]", hostname);
-	fprintf(stderr, ": ");
-
-	if(!fgets(line, sizeof line, stdin)) {
-		fprintf(stderr, "Error while reading stdin: %s\n", strerror(errno));
-		free(hostname);
+	if(!hostname)
 		return NULL;
-	}
 
-	if(!rstrip(line)) {
-		if(hostname)
-			goto save;
-		else
-			goto again;
-	}
-
-	for(char *p = line; *p; p++) {
-		if(isalnum(*p) || *p == '-' || *p == '.')
-			continue;
-		fprintf(stderr, "Invalid address or hostname.\n");
-		goto again;
-	}
-
-	free(hostname);
-	hostname = xstrdup(line);
-
-save:
-	if(filename) {
-		FILE *f = fopen(filename, "a");
-		if(f) {
-			fprintf(f, "\nAddress = %s\n", hostname);
-			fclose(f);
-		} else {
-			fprintf(stderr, "Could not append Address to %s: %s\n", filename, strerror(errno));
-		}
+	f = fopen(filename, "a");
+	if(f) {
+		fprintf(f, "\nAddress = %s\n", hostname);
+		fclose(f);
+	} else {
+		fprintf(stderr, "Could not append Address to %s: %s\n", filename, strerror(errno));
 	}
 
 done:
@@ -365,17 +316,61 @@ static char *get_value(const char *data, const char *var) {
 		return NULL;
 	return val;
 }
-static FILE *fopenmask(const char *filename, const char *mode, mode_t perms) {
-	mode_t mask = umask(0);
-	perms &= ~mask;
-	umask(~perms);
-	FILE *f = fopen(filename, mode);
-#ifdef HAVE_FCHMOD
-	if((perms & 0444) && f)
-		fchmod(fileno(f), perms);
-#endif
-	umask(mask);
-	return f;
+
+static bool try_bind(int port) {
+	struct addrinfo *ai = NULL;
+	struct addrinfo hint = {
+		.ai_flags = AI_PASSIVE,
+		.ai_family = AF_UNSPEC,
+		.ai_socktype = SOCK_STREAM,
+		.ai_protocol = IPPROTO_TCP,
+	};
+
+	char portstr[16];
+	snprintf(portstr, sizeof portstr, "%d", port);
+
+	if(getaddrinfo(NULL, portstr, &hint, &ai) || !ai)
+		return false;
+
+	while(ai) {
+		int fd = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
+		if(!fd) {
+			freeaddrinfo(ai);
+			return false;
+		}
+		int result = bind(fd, ai->ai_addr, ai->ai_addrlen);
+		closesocket(fd);
+		if(result) {
+			freeaddrinfo(ai);
+			return false;
+		}
+		ai = ai->ai_next;
+	}
+
+	freeaddrinfo(ai);
+	return true;
+}
+
+static int check_port(meshlink_handle_t *mesh) {
+	for(int i = 0; i < 1000; i++) {
+		int port = 0x1000 + (rand() & 0x7fff);
+		if(try_bind(port)) {
+			char filename[PATH_MAX];
+			snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, mesh->name);
+			FILE *f = fopen(filename, "a");
+			if(!f) {
+				fprintf(stderr, "Please change MeshLink's Port manually.\n");
+				return 0;
+			}
+
+			fprintf(f, "Port = %d\n", port);
+			fclose(f);
+			return port;
+		}
+	}
+
+	fprintf(stderr, "Please change MeshLink's Port manually.\n");
+	return 0;
 }
 
 static bool finalize_join(meshlink_handle_t *mesh) {
@@ -390,33 +385,26 @@ static bool finalize_join(meshlink_handle_t *mesh) {
 		return false;
 	}
 
-	if(mkdir(mesh->confbase, 0777) && errno != EEXIST) {
-		fprintf(stderr, "Could not create directory %s: %s\n", mesh->confbase, strerror(errno));
-		return false;
-	}
-
-	if(mkdir(mesh->hosts_dir, 0777) && errno != EEXIST) {
-		fprintf(stderr, "Could not create directory %s: %s\n", mesh->hosts_dir, strerror(errno));
-		return false;
-	}
+	char filename[PATH_MAX];
+	snprintf(filename, sizeof filename, "%s" SLASH "meshlink.conf", mesh->confbase);
 
-	FILE *f = fopen(mesh->meshlink_conf, "w");
+	FILE *f = fopen(filename, "w");
 	if(!f) {
-		fprintf(stderr, "Could not create file %s: %s\n", mesh->meshlink_conf, strerror(errno));
+		fprintf(stderr, "Could not create file %s: %s\n", filename, strerror(errno));
 		return false;
 	}
 
 	fprintf(f, "Name = %s\n", name);
 
-	char filename[PATH_MAX];
-	snprintf(filename,PATH_MAX, "%s" SLASH "%s", mesh->hosts_dir, name);
+	snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, name);
 	FILE *fh = fopen(filename, "w");
 	if(!fh) {
 		fprintf(stderr, "Could not create file %s: %s\n", filename, strerror(errno));
+		fclose(f);
 		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;
@@ -481,7 +469,7 @@ static bool finalize_join(meshlink_handle_t *mesh) {
 			return false;
 		}
 
-		snprintf(filename,PATH_MAX, "%s" SLASH "%s", mesh->hosts_dir, value);
+		snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, value);
 		f = fopen(filename, "w");
 
 		if(!f) {
@@ -511,42 +499,31 @@ static bool finalize_join(meshlink_handle_t *mesh) {
 		fclose(f);
 	}
 
-	// Generate our key and send a copy to the server
-	ecdsa_t *key = ecdsa_generate();
-	if(!key)
-		return false;
-
-	char *b64key = ecdsa_get_base64_public_key(key);
+	char *b64key = ecdsa_get_base64_public_key(mesh->self->connection->ecdsa);
 	if(!b64key)
 		return false;
 
-	snprintf(filename,PATH_MAX, "%s" SLASH "ecdsa_key.priv", mesh->confbase);
-	f = fopenmask(filename, "w", 0600);
-
-	if(!ecdsa_write_pem_private_key(key, f)) {
-		fprintf(stderr, "Error writing private key!\n");
-		ecdsa_free(key);
-		fclose(f);
-		return false;
-	}
-
-	fclose(f);
-
 	fprintf(fh, "ECDSAPublicKey = %s\n", b64key);
+	fprintf(fh, "Port = %s\n", mesh->myport);
+
+	fclose(fh);
 
 	sptps_send_record(&(mesh->sptps), 1, b64key, strlen(b64key));
 	free(b64key);
 
-	ecdsa_free(key);
-
-	check_port(name);
+	free(mesh->self->name);
+	free(mesh->self->connection->name);
+	mesh->self->name = xstrdup(name);
+	mesh->self->connection->name = name;
 
 	fprintf(stderr, "Configuration stored in: %s\n", mesh->confbase);
 
+	load_all_nodes(mesh);
+
 	return true;
 }
 
-static bool invitation_send(void *handle, uint8_t type, const char *data, size_t len) {
+static bool invitation_send(void *handle, uint8_t type, const void *data, size_t len) {
 	meshlink_handle_t* mesh = handle;
 	while(len) {
 		int result = send(mesh->sock, data, len, 0);
@@ -560,7 +537,7 @@ static bool invitation_send(void *handle, uint8_t type, const char *data, size_t
 	return true;
 }
 
-static bool invitation_receive(void *handle, uint8_t type, const char *msg, uint16_t len) {
+static bool invitation_receive(void *handle, uint8_t type, const void *msg, uint16_t len) {
 	meshlink_handle_t* mesh = handle;
 	switch(type) {
 		case SPTPS_HANDSHAKE:
@@ -644,22 +621,24 @@ static bool sendline(int fd, char *format, ...) {
 
 	return true;
 }
-int rstrip(char *value) {
-	int len = strlen(value);
-	while(len && strchr("\t\r\n ", value[len - 1]))
-		value[--len] = 0;
-	return len;
-}
-
 
 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) {
@@ -671,6 +650,7 @@ 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");
@@ -678,8 +658,10 @@ 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);
@@ -689,17 +671,19 @@ 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);
@@ -711,122 +695,90 @@ static bool ecdsa_keygen(meshlink_handle_t *mesh) {
 	return true;
 }
 
-static bool try_bind(int port) {
-	struct addrinfo *ai = NULL;
-	struct addrinfo hint = {
-		.ai_flags = AI_PASSIVE,
-		.ai_family = AF_UNSPEC,
-		.ai_socktype = SOCK_STREAM,
-		.ai_protocol = IPPROTO_TCP,
-	};
-
-	char portstr[16];
-	snprintf(portstr, sizeof portstr, "%d", port);
-
-	if(getaddrinfo(NULL, portstr, &hint, &ai) || !ai)
-		return false;
-
-	while(ai) {
-		int fd = socket(ai->ai_family, SOCK_STREAM, IPPROTO_TCP);
-		if(!fd)
-			return false;
-		int result = bind(fd, ai->ai_addr, ai->ai_addrlen);
-		closesocket(fd);
-		if(result)
-			return false;
-		ai = ai->ai_next;
-	}
-
-	return true;
-}
-
-int check_port(meshlink_handle_t *mesh) {
-	if(try_bind(655))
-		return 655;
-
-	fprintf(stderr, "Warning: could not bind to port 655.\n");
-
-	for(int i = 0; i < 100; i++) {
-		int port = 0x1000 + (rand() & 0x7fff);
-		if(try_bind(port)) {
-			char filename[PATH_MAX];
-			snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, mesh->name);
-			FILE *f = fopen(filename, "a");
-			if(!f) {
-				fprintf(stderr, "Please change MeshLink's Port manually.\n");
-				return 0;
-			}
-
-			fprintf(f, "Port = %d\n", port);
-			fclose(f);
-			fprintf(stderr, "MeshLink will instead listen on port %d.\n", port);
-			return port;
-		}
-	}
-
-	fprintf(stderr, "Please change MeshLink's Port manually.\n");
-	return 0;
-}
-
 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;
 	}
 
-	snprintf(mesh->hosts_dir, sizeof mesh->hosts_dir, "%s" SLASH "hosts", mesh->confbase);
+	char filename[PATH_MAX];
+	snprintf(filename, sizeof filename, "%s" SLASH "hosts", mesh->confbase);
 
-	if(mkdir(mesh->hosts_dir, 0777) && errno != EEXIST) {
-		fprintf(stderr, "Could not create directory %s: %s\n", mesh->hosts_dir, strerror(errno));
+	if(mkdir(filename, 0777) && errno != EEXIST) {
+		fprintf(stderr, "Could not create directory %s: %s\n", filename, strerror(errno));
+		meshlink_errno = MESHLINK_ESTORAGE;
 		return false;
 	}
 
-	snprintf(mesh->meshlink_conf, sizeof mesh->meshlink_conf, "%s" SLASH "meshlink.conf", mesh->confbase);
+	snprintf(filename, sizeof filename, "%s" SLASH "meshlink.conf", mesh->confbase);
 
-	if(!access(mesh->meshlink_conf, F_OK)) {
-		fprintf(stderr, "Configuration file %s already exists!\n", mesh->meshlink_conf);
+	if(!access(filename, F_OK)) {
+		fprintf(stderr, "Configuration file %s already exists!\n", filename);
+		meshlink_errno = MESHLINK_EEXIST;
 		return false;
 	}
 
-	FILE *f = fopen(mesh->meshlink_conf, "w");
+	FILE *f = fopen(filename, "w");
 	if(!f) {
-		fprintf(stderr, "Could not create file %s: %s\n", mesh->meshlink_conf, strerror(errno));
-		return 1;
+		fprintf(stderr, "Could not create file %s: %s\n", filename, strerror(errno));
+		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);
 
 	return true;
 }
 
-meshlink_handle_t *meshlink_open(const char *confbase, const char *name) {
+meshlink_handle_t *meshlink_open(const char *confbase, const char *name, const char* appname) {
+	return meshlink_open_with_size(confbase, name, appname, sizeof(meshlink_handle_t));
+}
+
+meshlink_handle_t *meshlink_open_with_size(const char *confbase, const char *name, const char* appname, size_t size) {
+
 	// Validate arguments provided by the application
+	bool usingname = false;
 
 	if(!confbase || !*confbase) {
 		fprintf(stderr, "No confbase given!\n");
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
+
+	if(!appname || !*appname) {
+		fprintf(stderr, "No appname given!\n");
+		meshlink_errno = MESHLINK_EINVAL;
 		return NULL;
 	}
 
 	if(!name || !*name) {
 		fprintf(stderr, "No name given!\n");
-		return NULL;
+		//return NULL;
 	}
+	else { //check name only if there is a name != NULL
 
-	if(!check_id(name)) {
-		fprintf(stderr, "Invalid name given!\n");
-		return NULL;
+		if(!check_id(name)) {
+			fprintf(stderr, "Invalid name given!\n");
+			meshlink_errno = MESHLINK_EINVAL;
+			return NULL;
+		} else { usingname = true;}
 	}
 
-	meshlink_handle_t *mesh = xzalloc(sizeof *mesh);
+	meshlink_handle_t *mesh = xzalloc(size);
 	mesh->confbase = xstrdup(confbase);
-	mesh->name = xstrdup(name);
+	mesh->appname = xstrdup(appname);
+	if (usingname) mesh->name = xstrdup(name);
+	pthread_mutex_init ( &(mesh->nodes_mutex), NULL);
+	mesh->threadstarted = false;
 	event_loop_init(&mesh->loop);
 	mesh->loop.data = mesh;
 
@@ -841,10 +793,15 @@ 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;
 		}
 	}
 
@@ -852,51 +809,114 @@ 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;
+	WSAStartup(MAKEWORD(2, 2), &wsa_state);
+#endif
 
 	// 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);
 
+	fprintf(stderr, "Starting main_loop...\n");
 	main_loop(mesh);
+	fprintf(stderr, "main_loop returned.\n");
 
 	return NULL;
 }
 
 bool meshlink_start(meshlink_handle_t *mesh) {
+
+	fprintf(stderr, "meshlink_start called\n");
+
+	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;
+	}
+
 	// Start the main thread
 
 	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;
+
+	discovery_start(mesh);
+
 	return true;
 }
 
 void meshlink_stop(meshlink_handle_t *mesh) {
-	// TODO: close the listening sockets to signal the main thread to shut down
+
+	fprintf(stderr, "meshlink_stop called\n");
+	
+	if(!mesh) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return;
+	}
+
+	// Stop discovery
+	discovery_stop(mesh);
+
+	// Shut down a listening socket to signal the main thread to shut down
+
+	listen_socket_t *s = &mesh->listen_socket[0];
+	shutdown(s->tcp.fd, SHUT_RDWR);
 
 	// Wait for the main thread to finish
 
 	pthread_join(mesh->thread, NULL);
+	mesh->threadstarted = false;
+
+	// Fix the socket
+	
+	closesocket(s->tcp.fd);
+	io_del(&mesh->loop, &s->tcp);
+	s->tcp.fd = setup_listen_socket(&s->sa);
+	if(s->tcp.fd < 0)
+		logger(DEBUG_ALWAYS, LOG_ERR, "Could not repair listenen socket!");
+	else
+		io_add(&mesh->loop, &s->tcp, handle_new_meta_connection, s, s->tcp.fd, IO_READ);
 }
 
 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);
@@ -905,116 +925,237 @@ void meshlink_close(meshlink_handle_t *mesh) {
 
 	exit_configuration(&mesh->config);
 	event_loop_exit(&mesh->loop);
+
+#ifdef HAVE_MINGW
+	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;
+	}
+
+	//add packet to the queue
+	outpacketqueue_t *packet_in_queue = xzalloc(sizeof *packet_in_queue);
+	packet_in_queue->destination=destination;
+	packet_in_queue->data=data;
+	packet_in_queue->len=len;
+	if(!meshlink_queue_push(&mesh->outpacketqueue, packet_in_queue)) {
+		free(packet_in_queue);
+		return false;
+	}
+
+	//notify event loop
+	signal_trigger(&(mesh->loop),&(mesh->datafromapp));
+	return true;
+}
+
+void meshlink_send_from_queue(event_loop_t* el,meshlink_handle_t *mesh) {
 	vpn_packet_t packet;
 	meshlink_packethdr_t *hdr = (meshlink_packethdr_t *)packet.data;
-	if (sizeof(meshlink_packethdr_t) + len > MAXSIZE) {
+
+	outpacketqueue_t* p = meshlink_queue_pop(&mesh->outpacketqueue);
+	if(!p)
+		return;
+
+	if (sizeof(meshlink_packethdr_t) + p->len > MAXSIZE) {
 		//log something
-		return false;
+		return ;
 	}
 
 	packet.probe = false;
 	memset(hdr, 0, sizeof *hdr);
-	memcpy(hdr->destination, destination->name, sizeof hdr->destination);
+	memcpy(hdr->destination, p->destination->name, sizeof hdr->destination);
 	memcpy(hdr->source, mesh->self->name, sizeof hdr->source);
 
-	packet.len = sizeof *hdr + len;
-	memcpy(packet.data + sizeof *hdr, data, len);
+	packet.len = sizeof *hdr + p->len;
+	memcpy(packet.data + sizeof *hdr, p->data, p->len);
 
         mesh->self->in_packets++;
         mesh->self->in_bytes += packet.len;
         route(mesh, mesh->self, &packet);
-	return false;
+	return ;
 }
 
-meshlink_node_t *meshlink_get_node(meshlink_handle_t *mesh, const char *name) {
-	return (meshlink_node_t *)lookup_node(mesh, name);
-	return NULL;
-}
+ssize_t meshlink_get_pmtu(meshlink_handle_t *mesh, meshlink_node_t *destination) {
+	if(!mesh || !destination) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return -1;
+	}
 
-size_t meshlink_get_all_nodes(meshlink_handle_t *mesh, meshlink_node_t **nodes, size_t nmemb) {
-	return 0;
+	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_sign(meshlink_handle_t *mesh, const char *data, size_t len) {
-	return NULL;
-}
+char *meshlink_get_fingerprint(meshlink_handle_t *mesh, meshlink_node_t *node) {
+	if(!mesh || !node) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return NULL;
+	}
 
-bool meshlink_verify(meshlink_handle_t *mesh, meshlink_node_t *source, const char *data, size_t len, const char *signature) {
-	return false;
+	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;
 }
 
-char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
-	// Check validity of the new node's name
-	if(!check_id(name)) {
-		fprintf(stderr, "Invalid name for node.\n");
+meshlink_node_t *meshlink_get_node(meshlink_handle_t *mesh, const char *name) {
+	if(!mesh || !name) {
+		meshlink_errno = MESHLINK_EINVAL;
 		return NULL;
 	}
 
-	char *myname = get_my_name(mesh);
-	if(!myname) {
-		fprintf(stderr, "Could not determine my own name.\n");
+	return (meshlink_node_t *)lookup_node(mesh, (char *)name); // TODO: make lookup_node() use const
+}
+
+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;
 	}
 
-	// Ensure no host configuration file with that name exists
-	char filename [PATH_MAX];
-	snprintf(filename,PATH_MAX, "%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);
-		return NULL;
+	meshlink_node_t **result;
+
+	//lock mesh->nodes
+	pthread_mutex_lock(&(mesh->nodes_mutex));
+
+	*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;
 	}
 
-	// If a daemon is running, ensure no other nodes know about this name
+	pthread_mutex_unlock(&(mesh->nodes_mutex));
 
-	//TODO: original tinc code connects to tincd cli and makes this check. How we want to implement this here ?
-	//bool found = false;
-	//if(connect_tincd(false)) {
-	//	sendline(fd, "%d %d", CONTROL, REQ_DUMP_NODES);
+	return result;
+}
 
-	//	while(recvline(fd, line, sizeof line)) {
-	//		char node[4096];
-	//		int code, req;
-	//		if(sscanf(line, "%d %d %s", &code, &req, node) != 3)
-	//			break;
-	//		if(!strcmp(node, name))
-	//			found = true;
-	//	}
+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(found) {
-	//		fprintf(stderr, "A node with name %s is already known!\n", name);
-	//		return 1;
-	//	}
-	//}
+	if(*siglen < MESHLINK_SIGLEN) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
+	}
 
-	char hash[64];
+	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 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) {
+	char filename[PATH_MAX];
 
-	snprintf(filename,PATH_MAX, "%s" SLASH "invitations", mesh->confbase);
+	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));
-		return NULL;
+		meshlink_errno = MESHLINK_ESTORAGE;
+		return false;
 	}
 
 	// Count the number of valid invitations, clean up old ones
 	DIR *dir = opendir(filename);
 	if(!dir) {
 		fprintf(stderr, "Could not read directory %s: %s\n", filename, strerror(errno));
-		return NULL;
+		meshlink_errno = MESHLINK_ESTORAGE;
+		return false;
 	}
 
 	errno = 0;
@@ -1027,9 +1168,9 @@ char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
 			continue;
 		char invname[PATH_MAX];
 		struct stat st;
-		snprintf(invname,PATH_MAX, "%s" SLASH "%s", filename, ent->d_name);
+		snprintf(invname, sizeof invname, "%s" SLASH "%s", filename, ent->d_name);
 		if(!stat(invname, &st)) {
-			if(deadline < st.st_mtime)
+			if(mesh->invitation_key && deadline < st.st_mtime)
 				count++;
 			else
 				unlink(invname);
@@ -1042,54 +1183,125 @@ char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
 	if(errno) {
 		fprintf(stderr, "Error while reading directory %s: %s\n", filename, strerror(errno));
 		closedir(dir);
-		return NULL;
+		meshlink_errno = MESHLINK_ESTORAGE;
+		return false;
 	}
 
 	closedir(dir);
 
-	ecdsa_t *key;
-	snprintf(filename,PATH_MAX, "%s" SLASH "invitations" SLASH "ecdsa_key.priv", mesh->confbase);
+	snprintf(filename, sizeof filename, "%s" SLASH "invitations" SLASH "ecdsa_key.priv", mesh->confbase);
 
 	// Remove the key if there are no outstanding invitations.
-	if(!count)
+	if(!count) {
 		unlink(filename);
+		if(mesh->invitation_key) {
+			ecdsa_free(mesh->invitation_key);
+			mesh->invitation_key = NULL;
+		}
+	}
+
+	if(mesh->invitation_key)
+		return true;
 
 	// Create a new key if necessary.
 	FILE *f = fopen(filename, "r");
 	if(!f) {
 		if(errno != ENOENT) {
 			fprintf(stderr, "Could not read %s: %s\n", filename, strerror(errno));
-			return NULL;
+			meshlink_errno = MESHLINK_ESTORAGE;
+			return false;
 		}
 
-		key = ecdsa_generate();
-		if(!key) {
+		mesh->invitation_key = ecdsa_generate();
+		if(!mesh->invitation_key) {
 			fprintf(stderr, "Could not generate a new key!\n");
-			return NULL;
+			meshlink_errno = MESHLINK_EINTERNAL;
+			return false;
 		}
 		f = fopen(filename, "w");
 		if(!f) {
 			fprintf(stderr, "Could not write %s: %s\n", filename, strerror(errno));
-			return NULL;
+			meshlink_errno = MESHLINK_ESTORAGE;
+			return false;
 		}
 		chmod(filename, 0600);
-		ecdsa_write_pem_private_key(key, f);
+		ecdsa_write_pem_private_key(mesh->invitation_key, f);
 		fclose(f);
-		//TODO: handle this in meshlink
-		//if(connect_tincd(false))
-		//	sendline(fd, "%d %d", CONTROL, REQ_RELOAD);
 	} else {
-		key = ecdsa_read_pem_private_key(f);
+		mesh->invitation_key = ecdsa_read_pem_private_key(f);
 		fclose(f);
-		if(!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;
+	}
+
+	return append_config_file(mesh, mesh->self->name, "Address", 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;
+	}
+
+	// Ensure no host configuration file with that name exists
+	char filename[PATH_MAX];
+	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;
 	}
 
-	if(!key)
+	// Get the local address
+	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)) {
+		meshlink_errno = MESHLINK_EINTERNAL;
 		return NULL;
+	}
+
+	char hash[64];
 
 	// Create a hash of the key.
-	char *fingerprint = ecdsa_get_base64_public_key(key);
+	char *fingerprint = ecdsa_get_base64_public_key(mesh->invitation_key);
 	sha512(fingerprint, strlen(fingerprint), hash);
 	b64encode_urlsafe(hash, hash, 18);
 
@@ -1107,28 +1319,29 @@ 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,PATH_MAX, "%s" SLASH "invitations" SLASH "%s", mesh->confbase, cookiehash);
+	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;
 	}
-	f = fdopen(ifd, "w");
+	FILE *f = fdopen(ifd, "w");
 	if(!f)
 		abort();
 
-	// Get the local address
-	char *address = get_my_hostname(mesh);
-
 	// Fill in the details.
 	fprintf(f, "Name = %s\n", name);
 	//if(netname)
 	//	fprintf(f, "NetName = %s\n", netname);
-	fprintf(f, "ConnectTo = %s\n", myname);
+	fprintf(f, "ConnectTo = %s\n", mesh->self->name);
 
 	// Copy Broadcast and Mode
-	FILE *tc = fopen(mesh->meshlink_conf, "r");
+	snprintf(filename, sizeof filename, "%s" SLASH "meshlink.conf", mesh->confbase);
+	FILE *tc = fopen(filename,  "r");
 	if(tc) {
 		char buf[1024];
 		while(fgets(buf, sizeof buf, tc)) {
@@ -1141,45 +1354,40 @@ 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;
 	}
 
 	fprintf(f, "#---------------------------------------------------------------#\n");
-	fprintf(f, "Name = %s\n", myname);
+	fprintf(f, "Name = %s\n", mesh->self->name);
 
-	char filename2[PATH_MAX];
-	snprintf(filename2,PATH_MAX, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, myname);
-	fcopy(f, filename2);
+	snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, mesh->self->name);
+	fcopy(f, filename);
 	fclose(f);
 
 	// 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) {
-
-
-	// Make sure confbase exists and is accessible.
-	if(mkdir(mesh->confbase, 0777) && errno != EEXIST) {
-		fprintf(stderr, "Could not create directory %s: %s\n", mesh->confbase, strerror(errno));
-		return 1;
+	if(!mesh || !invitation) {
+		meshlink_errno = MESHLINK_EINVAL;
+		return false;
 	}
 
-	if(access(mesh->confbase, R_OK | W_OK | X_OK)) {
-		fprintf(stderr, "No permission to write in directory %s: %s\n", mesh->confbase, strerror(errno));
-		return 1;
-	}
+	//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);
 
-	// TODO: Either remove or reintroduce netname in meshlink
-	// If a netname or explicit configuration directory is specified, check for an existing meshlink.conf.
-	//if((mesh->netname || confbasegiven) && !access(meshlink_conf, F_OK)) {
-	//	fprintf(stderr, "Configuration file %s already exists!\n", meshlink_conf);
-	//	return 1;
-	//}
+	// Split the invitation URL into hostname, port, key hash and cookie.
 
-	char *slash = strchr(invitation, '/');
+	char *slash = strchr(copy, '/');
 	if(!slash)
 		goto invalid;
 
@@ -1188,7 +1396,7 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 	if(strlen(slash) != 48)
 		goto invalid;
 
-	char *address = invitation;
+	char *address = copy;
 	char *port = NULL;
 	if(*address == '[') {
 		address++;
@@ -1204,93 +1412,124 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 			*port++ = 0;
 	}
 
-	if(!mesh->myport || !*port)
-		port = "655";
+	if(!port)
+		goto invalid;
 
 	if(!b64decode(slash, mesh->hash, 18) || !b64decode(slash + 24, mesh->cookie, 18))
 		goto invalid;
 
 	// Generate a throw-away key for the invitation.
 	ecdsa_t *key = ecdsa_generate();
-	if(!key)
-		return 1;
+	if(!key) {
+		meshlink_errno = MESHLINK_EINTERNAL;
+		return false;
+	}
 
 	char *b64key = ecdsa_get_base64_public_key(key);
 
+	//Before doing meshlink_join make sure we are not connected to another mesh
+	if ( mesh->threadstarted ){
+		goto invalid;
+	}
+
 	// Connect to the meshlink daemon mentioned in the URL.
 	struct addrinfo *ai = str2addrinfo(address, port, SOCK_STREAM);
-	if(!ai)
-		return 1;
+	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));
-		return 1;
+		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);
-		return 1;
+		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.
-	int len = snprintf(invitation, sizeof invitation, "0 ?%s %d.%d\n", b64key, PROT_MAJOR, PROT_MINOR);
-	if(len <= 0 || len >= sizeof invitation)
-		abort();
+
+	mesh->blen = 0;
 
 	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);
-		return 1;
+		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);
-		return 1;
+		meshlink_errno = MESHLINK_ENETWORK;
+		return false;
 	}
 
 	// Check if the hash of the key he gave us matches the hash in the URL.
 	char *fingerprint = mesh->line + 2;
 	char hishash[64];
-	if(!sha512(fingerprint, strlen(fingerprint), hishash)) {
+	if(sha512(fingerprint, strlen(fingerprint), hishash)) {
 		fprintf(stderr, "Could not create hash\n%s\n", mesh->line + 2);
-		return 1;
+		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);
-		return 1;
+		meshlink_errno = MESHLINK_EPEER;
+		return false;
 
 	}
 
 	ecdsa_t *hiskey = ecdsa_set_base64_public_key(fingerprint);
-	if(!hiskey)
-		return 1;
+	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))
-		return 1;
+	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))
-		return 1;
+	if(!sptps_receive_data(&mesh->sptps, mesh->buffer, mesh->blen)) {
+		meshlink_errno = MESHLINK_EPEER;
+		return false;
+	}
+
+	int len;
 
 	while((len = recv(mesh->sock, mesh->line, sizeof mesh->line, 0))) {
 		if(len < 0) {
 			if(errno == EINTR)
 				continue;
 			fprintf(stderr, "Error reading data from %s port %s: %s\n", address, port, strerror(errno));
-			return 1;
+			meshlink_errno = MESHLINK_ENETWORK;
+			return false;
 		}
 
-		if(!sptps_receive_data(&mesh->sptps, mesh->line, len))
-			return 1;
+		if(!sptps_receive_data(&mesh->sptps, mesh->line, len)) {
+			meshlink_errno = MESHLINK_EPEER;
+			return false;
+		}
 	}
 
 	sptps_stop(&mesh->sptps);
@@ -1300,25 +1539,179 @@ 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;
 	}
 
 	return true;
 
 invalid:
-	fprintf(stderr, "Invalid invitation URL.\n");
+	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) {
-	return NULL;
+	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;
+	}
+
+	fseek(f, 0, SEEK_END);
+	int fsize = ftell(f);
+	rewind(f);
+
+	size_t len = fsize + 9 + strlen(mesh->self->name);
+	char *buf = xmalloc(len);
+	snprintf(buf, len, "Name = %s\n", mesh->self->name);
+	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;
+	}
+
+	fclose(f);
+	buf[len - 1] = 0;
+	return buf;
 }
 
 bool meshlink_import(meshlink_handle_t *mesh, const char *data) {
-	return false;
+	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;
+	}
+
+	int len = end - (data + 7);
+	char name[len + 1];
+	memcpy(name, data + 7, len);
+	name[len] = 0;
+	if(!check_id(name)) {
+		fprintf(stderr, "Invalid Name\n");
+		meshlink_errno = MESHLINK_EPEER;
+		return false;
+	}
+
+	char filename[PATH_MAX];
+	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;
+	}
+
+	fwrite(end + 1, strlen(end + 1), 1, f);
+	fclose(f);
+
+	load_all_nodes(mesh);
+
+	return true;
 }
 
 void meshlink_blacklist(meshlink_handle_t *mesh, meshlink_node_t *node) {
+	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;
+}
+
+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;
+}
+
+/* Hint that a hostname may be found at an address
+ * See header file for detailed comment.
+ */
+extern void meshlink_hint_address(meshlink_handle_t *mesh, meshlink_node_t *node, struct sockaddr *addr) {
+	if(!mesh || !node || !addr)
+		return;
+	
+	char *addr_str = malloc(MAX_ADDRESS_LENGTH*sizeof(char));
+	memset(addr_str, 0, MAX_ADDRESS_LENGTH*sizeof(char));
+
+	char *port_str = malloc(MAX_PORT_LENGTH*sizeof(char));
+	memset(port_str, 0, MAX_PORT_LENGTH*sizeof(char));
+	
+	// extra byte for a space, and one to make sure string is null-terminated
+	int full_addr_len = MAX_ADDRESS_LENGTH + MAX_PORT_LENGTH + 2;
+
+	char *full_addr_str = malloc(full_addr_len*sizeof(char));
+	memset(full_addr_str, 0, full_addr_len*sizeof(char));
+	
+	// get address and port number
+	if(!get_ip_str(addr, addr_str, MAX_ADDRESS_LENGTH))
+		goto fail;
+	if(!get_port_str(addr, port_str, MAX_ADDRESS_LENGTH))
+		goto fail;
+
+	// append_config_file expects an address, a space, and then a port number
+	strcat(full_addr_str, addr_str);
+	strcat(full_addr_str, " ");
+	strcat(full_addr_str, port_str);
+	
+	append_config_file(mesh, node->name, "Address", full_addr_str);
+
+fail:
+	free(addr_str);
+	free(port_str);
+	free(full_addr_str);
+
+	// @TODO do we want to fire off a connection attempt right away?
 }
 
 static void __attribute__((constructor)) meshlink_init(void) {