X-Git-Url: http://git.meshlink.io/?a=blobdiff_plain;f=src%2Fmeshlink.c;h=2aa79def7d47c6762e01f30715cb14e277933991;hb=2cfd1205dc9c6e9d42cc569f415afe13f52357ec;hp=bab306689ba07e9ff919e519f3892256d7dd400f;hpb=8398c492306f3b3f8d71eeed15d14da3a67e1372;p=meshlink

diff --git a/src/meshlink.c b/src/meshlink.c
index bab30668..2aa79def 100644
--- a/src/meshlink.c
+++ b/src/meshlink.c
@@ -32,25 +32,14 @@ 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"
 
-//TODO: move all of this to meshlink_handle_t
-static	char meshlink_conf[PATH_MAX];
-static	char hosts_dir[PATH_MAX];
-
-static	int sock;
-static	sptps_t sptps;
-static	char cookie[18], hash[18];
-static 	char *data = NULL;
-static 	size_t thedatalen = 0;
-static 	bool success = false;
-static 	char line[4096];
-static 	char buffer[4096];
-static 	size_t blen = 0;
 
 //TODO: this can go away completely
 const var_t variables[] = {
@@ -116,6 +105,198 @@ const var_t variables[] = {
 	{NULL, 0}
 };
 
+static bool fcopy(FILE *out, const char *filename) {
+	FILE *in = fopen(filename, "r");
+	if(!in) {
+		fprintf(stderr, "Could not open %s: %s\n", filename, strerror(errno));
+		return false;
+	}
+
+	char buf[1024];
+	size_t len;
+	while((len = fread(buf, 1, sizeof buf, in)))
+		fwrite(buf, len, 1, out);
+	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))
+		return;
+
+	FILE *f = fopen(filename, "r");
+	if(!f)
+		return;
+
+	while(fgets(line, sizeof line, f)) {
+		if(!rstrip(line))
+			continue;
+		char *p = line, *q;
+		p += strcspn(p, "\t =");
+		if(!*p)
+			continue;
+		q = p + strspn(p, "\t ");
+		if(*q == '=')
+			q += 1 + strspn(q + 1, "\t ");
+		*p = 0;
+		p = q + strcspn(q, "\t ");
+		if(*p)
+			*p++ = 0;
+		p += strspn(p, "\t ");
+		p[strcspn(p, "\t ")] = 0;
+
+		if(!*port && !strcasecmp(line, "Port")) {
+			*port = xstrdup(q);
+		} else if(!*hostname && !strcasecmp(line, "Address")) {
+			*hostname = xstrdup(q);
+			if(*p) {
+				free(*port);
+				*port = xstrdup(p);
+			}
+		}
+
+		if(*hostname && *port)
+			break;
+	}
+
+	fclose(f);
+}
+static char *get_my_hostname(meshlink_handle_t* mesh) {
+	char *hostname = NULL;
+	char *port = NULL;
+	char *hostport = NULL;
+	char *name = mesh->self->name;
+	char filename[PATH_MAX] = "";
+	char line[4096];
+	FILE *f;
+
+	// Use first Address statement in own host config file
+	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 *aip = ai;
+	static const char request[] = "GET http://tinc-vpn.org/host.cgi HTTP/1.0\r\n\r\n";
+
+	while(aip) {
+		int s = socket(aip->ai_family, aip->ai_socktype, aip->ai_protocol);
+		if(s >= 0) {
+			if(connect(s, aip->ai_addr, aip->ai_addrlen)) {
+				closesocket(s);
+				s = -1;
+			}
+		}
+		if(s >= 0) {
+			send(s, request, sizeof request - 1, 0);
+			int len = recv(s, line, sizeof line - 1, MSG_WAITALL);
+			if(len > 0) {
+				line[len] = 0;
+				if(line[len - 1] == '\n')
+					line[--len] = 0;
+				char *p = strrchr(line, '\n');
+				if(p && p[1])
+					hostname = xstrdup(p + 1);
+			}
+			closesocket(s);
+			if(hostname)
+				break;
+		}
+		aip = aip->ai_next;
+		continue;
+	}
+
+	if(ai)
+		freeaddrinfo(ai);
+
+	// Check that the hostname is reasonable
+	if(hostname) {
+		for(char *p = hostname; *p; p++) {
+			if(isalnum(*p) || *p == '-' || *p == '.' || *p == ':')
+				continue;
+			// If not, forget it.
+			free(hostname);
+			hostname = NULL;
+			break;
+		}
+	}
+
+	//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);
+		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:
+	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:
+	if(port) {
+		if(strchr(hostname, ':'))
+			xasprintf(&hostport, "[%s]:%s", hostname, port);
+		else
+			xasprintf(&hostport, "%s:%s", hostname, port);
+	} else {
+		if(strchr(hostname, ':'))
+			xasprintf(&hostport, "[%s]", hostname);
+		else
+			hostport = xstrdup(hostname);
+	}
+
+	free(hostname);
+	free(port);
+	return hostport;
+}
+
 static char *get_line(const char **data) {
 	if(!data || !*data)
 		return NULL;
@@ -160,21 +341,66 @@ 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)
+			return false;
+		int result = bind(fd, ai->ai_addr, ai->ai_addrlen);
+		closesocket(fd);
+		if(result)
+			return false;
+		ai = ai->ai_next;
+	}
+
+	return true;
+}
+
+static 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 finalize_join(meshlink_handle_t *mesh) {
-	char *name = xstrdup(get_value(data, "Name"));
+	char *name = xstrdup(get_value(mesh->data, "Name"));
 	if(!name) {
 		fprintf(stderr, "No Name found in invitation!\n");
 		return false;
@@ -185,35 +411,28 @@ 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(hosts_dir, 0777) && errno != EEXIST) {
-		fprintf(stderr, "Could not create directory %s: %s\n", hosts_dir, strerror(errno));
-		return false;
-	}
+	char filename[PATH_MAX];
+	snprintf(filename, sizeof filename, "%s" SLASH "meshlink.conf", mesh->confbase);
 
-	FILE *f = fopen(meshlink_conf, "w");
+	FILE *f = fopen(filename, "w");
 	if(!f) {
-		fprintf(stderr, "Could not create file %s: %s\n", 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", 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
 	// Other chunks go unfiltered to their respective host config files
-	const char *p = data;
+	const char *p = mesh->data;
 	char *l, *value;
 
 	while((l = get_line(&p))) {
@@ -276,7 +495,7 @@ static bool finalize_join(meshlink_handle_t *mesh) {
 			return false;
 		}
 
-		snprintf(filename,PATH_MAX, "%s" SLASH "%s", hosts_dir, value);
+		snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, value);
 		f = fopen(filename, "w");
 
 		if(!f) {
@@ -306,44 +525,34 @@ 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);
 
-	sptps_send_record(&sptps, 1, b64key, strlen(b64key));
-	free(b64key);
+	fclose(fh);
 
-	ecdsa_free(key);
+	sptps_send_record(&(mesh->sptps), 1, b64key, strlen(b64key));
+	free(b64key);
 
-	check_port(name);
+	free(mesh->self->name);
+	free(mesh->self->connection->name);
+	mesh->self->name = xstrdup(name);
+	mesh->self->connection->name = xstrdup(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(sock, data, len, 0);
+		int result = send(mesh->sock, data, len, 0);
 		if(result == -1 && errno == EINTR)
 			continue;
 		else if(result <= 0)
@@ -354,25 +563,26 @@ 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:
-			return sptps_send_record(&sptps, 0, cookie, sizeof cookie);
+			return sptps_send_record(&(mesh->sptps), 0, mesh->cookie, sizeof mesh->cookie);
 
 		case 0:
-			data = xrealloc(data, thedatalen + len + 1);
-			memcpy(data + thedatalen, msg, len);
-			thedatalen += len;
-			data[thedatalen] = 0;
+			mesh->data = xrealloc(mesh->data, mesh->thedatalen + len + 1);
+			memcpy(mesh->data + mesh->thedatalen, msg, len);
+			mesh->thedatalen += len;
+			mesh->data[mesh->thedatalen] = 0;
 			break;
 
 		case 1:
-			return finalize_join(NULL);//TODO: wrong, we have to pass the mesh handler here, but how ?
+			return finalize_join(mesh);
 
 		case 2:
 			fprintf(stderr, "Invitation succesfully accepted.\n");
-			shutdown(sock, SHUT_RDWR);
-			success = true;
+			shutdown(mesh->sock, SHUT_RDWR);
+			mesh->success = true;
 			break;
 
 		default:
@@ -382,30 +592,30 @@ static bool invitation_receive(void *handle, uint8_t type, const char *msg, uint
 	return true;
 }
 
-static bool recvline(int fd, char *line, size_t len) {
+static bool recvline(meshlink_handle_t* mesh, size_t len) {
 	char *newline = NULL;
 
-	if(!fd)
+	if(!mesh->sock)
 		abort();
 
-	while(!(newline = memchr(buffer, '\n', blen))) {
-		int result = recv(fd, buffer + blen, sizeof buffer - blen, 0);
+	while(!(newline = memchr(mesh->buffer, '\n', mesh->blen))) {
+		int result = recv(mesh->sock, mesh->buffer + mesh->blen, sizeof mesh->buffer - mesh->blen, 0);
 		if(result == -1 && errno == EINTR)
 			continue;
 		else if(result <= 0)
 			return false;
-		blen += result;
+		mesh->blen += result;
 	}
 
-	if(newline - buffer >= len)
+	if(newline - mesh->buffer >= len)
 		return false;
 
-	len = newline - buffer;
+	len = newline - mesh->buffer;
 
-	memcpy(line, buffer, len);
-	line[len] = 0;
-	memmove(buffer, newline + 1, blen - len - 1);
-	blen -= len + 1;
+	memcpy(mesh->line, mesh->buffer, len);
+	mesh->line[len] = 0;
+	memmove(mesh->buffer, newline + 1, mesh->blen - len - 1);
+	mesh->blen -= len + 1;
 
 	return true;
 }
@@ -437,13 +647,6 @@ 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",
@@ -504,87 +707,30 @@ 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));
 		return false;
 	}
 
-	snprintf(hosts_dir, sizeof hosts_dir, "%s" SLASH "hosts", mesh->confbase);
+	char filename[PATH_MAX];
+	snprintf(filename, sizeof filename, "%s" SLASH "hosts", mesh->confbase);
 
-	if(mkdir(hosts_dir, 0777) && errno != EEXIST) {
-		fprintf(stderr, "Could not create directory %s: %s\n", hosts_dir, strerror(errno));
+	if(mkdir(filename, 0777) && errno != EEXIST) {
+		fprintf(stderr, "Could not create directory %s: %s\n", filename, strerror(errno));
 		return false;
 	}
 
-	snprintf(meshlink_conf, sizeof meshlink_conf, "%s" SLASH "meshlink.conf", mesh->confbase);
+	snprintf(filename, sizeof filename, "%s" SLASH "meshlink.conf", mesh->confbase);
 
-	if(!access(meshlink_conf, F_OK)) {
-		fprintf(stderr, "Configuration file %s already exists!\n", meshlink_conf);
+	if(!access(filename, F_OK)) {
+		fprintf(stderr, "Configuration file %s already exists!\n", filename);
 		return false;
 	}
 
-	FILE *f = fopen(meshlink_conf, "w");
+	FILE *f = fopen(filename, "w");
 	if(!f) {
-		fprintf(stderr, "Could not create file %s: %s\n", meshlink_conf, strerror(errno));
+		fprintf(stderr, "Could not create file %s: %s\n", filename, strerror(errno));
 		return 1;
 	}
 
@@ -736,12 +882,19 @@ bool meshlink_send(meshlink_handle_t *mesh, meshlink_node_t *destination, const
 }
 
 meshlink_node_t *meshlink_get_node(meshlink_handle_t *mesh, const char *name) {
-	return (meshlink_node_t *)lookup_node(mesh, name);
-	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) {
-	return 0;
+	size_t i = 0;
+
+	for splay_each(node_t, n, mesh->nodes) {
+		if(i < nmemb)
+			nodes[i] = (meshlink_node_t *)n;
+		i++;
+	}
+
+	return i;
 }
 
 char *meshlink_sign(meshlink_handle_t *mesh, const char *data, size_t len) {
@@ -752,32 +905,204 @@ bool meshlink_verify(meshlink_handle_t *mesh, meshlink_node_t *source, const cha
 	return false;
 }
 
-char *meshlink_invite(meshlink_handle_t *mesh, const char *name) {
-	return NULL;
+static bool refresh_invitation_key(meshlink_handle_t *mesh) {
+	char filename[PATH_MAX];
+
+	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;
+	}
+
+	// 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;
+	}
+
+	errno = 0;
+	int count = 0;
+	struct dirent *ent;
+	time_t deadline = time(NULL) - 604800; // 1 week in the past
+
+	while((ent = readdir(dir))) {
+		if(strlen(ent->d_name) != 24)
+			continue;
+		char invname[PATH_MAX];
+		struct stat st;
+		snprintf(invname, sizeof invname, "%s" SLASH "%s", filename, ent->d_name);
+		if(!stat(invname, &st)) {
+			if(mesh->invitation_key && deadline < st.st_mtime)
+				count++;
+			else
+				unlink(invname);
+		} else {
+			fprintf(stderr, "Could not stat %s: %s\n", invname, strerror(errno));
+			errno = 0;
+		}
+	}
+
+	if(errno) {
+		fprintf(stderr, "Error while reading directory %s: %s\n", filename, strerror(errno));
+		closedir(dir);
+		return false;
+	}
+
+	closedir(dir);
+
+	snprintf(filename, sizeof filename, "%s" SLASH "invitations" SLASH "ecdsa_key.priv", mesh->confbase);
+
+	// Remove the key if there are no outstanding invitations.
+	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;
+		}
+
+		mesh->invitation_key = ecdsa_generate();
+		if(!mesh->invitation_key) {
+			fprintf(stderr, "Could not generate a new key!\n");
+			return NULL;
+		}
+		f = fopen(filename, "w");
+		if(!f) {
+			fprintf(stderr, "Could not write %s: %s\n", filename, strerror(errno));
+			return NULL;
+		}
+		chmod(filename, 0600);
+		ecdsa_write_pem_private_key(mesh->invitation_key, f);
+		fclose(f);
+	} else {
+		mesh->invitation_key = ecdsa_read_pem_private_key(f);
+		fclose(f);
+		if(!mesh->invitation_key)
+			fprintf(stderr, "Could not read private key from %s\n", filename);
+	}
+
+	return mesh->invitation_key;
 }
 
-bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
+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");
+		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);
+		return NULL;
+	}
 
-	// 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;
+	// 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);
+		return NULL;
 	}
 
-	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;
+	if(!refresh_invitation_key(mesh))
+		return NULL;
+
+	char hash[64];
+
+	// Create a hash of the key.
+	char *fingerprint = ecdsa_get_base64_public_key(mesh->invitation_key);
+	sha512(fingerprint, strlen(fingerprint), hash);
+	b64encode_urlsafe(hash, hash, 18);
+
+	// Create a random cookie for this invitation.
+	char cookie[25];
+	randomize(cookie, 18);
+
+	// Create a filename that doesn't reveal the cookie itself
+	char buf[18 + strlen(fingerprint)];
+	char cookiehash[64];
+	memcpy(buf, cookie, 18);
+	memcpy(buf + 18, fingerprint, sizeof buf - 18);
+	sha512(buf, sizeof buf, cookiehash);
+	b64encode_urlsafe(cookiehash, cookiehash, 18);
+
+	b64encode_urlsafe(cookie, cookie, 18);
+
+	// 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));
+		return NULL;
 	}
+	FILE *f = fdopen(ifd, "w");
+	if(!f)
+		abort();
 
-	// 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;
-	//}
+	// Get the local address
+	char *address = get_my_hostname(mesh);
 
-	char *slash = strchr(invitation, '/');
+	// Fill in the details.
+	fprintf(f, "Name = %s\n", name);
+	//if(netname)
+	//	fprintf(f, "NetName = %s\n", netname);
+	fprintf(f, "ConnectTo = %s\n", mesh->self->name);
+
+	// Copy Broadcast and Mode
+	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)) {
+			if((!strncasecmp(buf, "Mode", 4) && strchr(" \t=", buf[4]))
+					|| (!strncasecmp(buf, "Broadcast", 9) && strchr(" \t=", buf[9]))) {
+				fputs(buf, f);
+				// Make sure there is a newline character.
+				if(!strchr(buf, '\n'))
+					fputc('\n', f);
+			}
+		}
+		fclose(tc);
+	} else {
+		fprintf(stderr, "Could not create %s: %s\n", filename, strerror(errno));
+		return NULL;
+	}
+
+	fprintf(f, "#---------------------------------------------------------------#\n");
+	fprintf(f, "Name = %s\n", mesh->self->name);
+
+	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);
+
+	return url;
+}
+
+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];
+	strcpy(copy, invitation);
+
+	// Split the invitation URL into hostname, port, key hash and cookie.
+
+	char *slash = strchr(copy, '/');
 	if(!slash)
 		goto invalid;
 
@@ -786,7 +1111,7 @@ 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++;
@@ -802,101 +1127,102 @@ bool meshlink_join(meshlink_handle_t *mesh, const char *invitation) {
 			*port++ = 0;
 	}
 
-	if(!mesh->myport || !*port)
+	if(!*port)
 		port = "655";
 
-	if(!b64decode(slash, hash, 18) || !b64decode(slash + 24, cookie, 18))
+	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;
+		return false;
 
 	char *b64key = ecdsa_get_base64_public_key(key);
 
 	// Connect to the meshlink daemon mentioned in the URL.
 	struct addrinfo *ai = str2addrinfo(address, port, SOCK_STREAM);
 	if(!ai)
-		return 1;
+		return false;
 
-	sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
-	if(sock <= 0) {
+	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;
+		return false;
 	}
 
-	if(connect(sock, ai->ai_addr, ai->ai_addrlen)) {
+	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(sock);
-		return 1;
+		closesocket(mesh->sock);
+		return false;
 	}
 
 	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();
 
-	if(!sendline(sock, "0 ?%s %d.%d", b64key, PROT_MAJOR, 1)) {
+	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(sock);
-		return 1;
+		closesocket(mesh->sock);
+		return false;
 	}
 
 	char hisname[4096] = "";
 	int code, hismajor, hisminor = 0;
 
-	if(!recvline(sock, line, sizeof line) || sscanf(line, "%d %s %d.%d", &code, hisname, &hismajor, &hisminor) < 3 || code != 0 || hismajor != PROT_MAJOR || !check_id(hisname) || !recvline(sock, line, sizeof line) || !rstrip(line) || sscanf(line, "%d ", &code) != 1 || code != ACK || strlen(line) < 3) {
+	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(sock);
-		return 1;
+		closesocket(mesh->sock);
+		return false;
 	}
 
 	// Check if the hash of the key he gave us matches the hash in the URL.
-	char *fingerprint = line + 2;
+	char *fingerprint = mesh->line + 2;
 	char hishash[64];
-	if(!sha512(fingerprint, strlen(fingerprint), hishash)) {
-		fprintf(stderr, "Could not create hash\n%s\n", line + 2);
-		return 1;
+	if(sha512(fingerprint, strlen(fingerprint), hishash)) {
+		fprintf(stderr, "Could not create hash\n%s\n", mesh->line + 2);
+		return false;
 	}
-	if(memcmp(hishash, hash, 18)) {
-		fprintf(stderr, "Peer has an invalid key!\n%s\n", line + 2);
-		return 1;
+	if(memcmp(hishash, mesh->hash, 18)) {
+		fprintf(stderr, "Peer has an invalid key!\n%s\n", mesh->line + 2);
+		return false;
 
 	}
 
 	ecdsa_t *hiskey = ecdsa_set_base64_public_key(fingerprint);
 	if(!hiskey)
-		return 1;
+		return false;
 
 	// Start an SPTPS session
-	if(!sptps_start(&sptps, NULL, 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))
+		return false;
 
 	// Feed rest of input buffer to SPTPS
-	if(!sptps_receive_data(&sptps, buffer, blen))
-		return 1;
+	if(!sptps_receive_data(&mesh->sptps, mesh->buffer, mesh->blen))
+		return false;
+
+	int len;
 
-	while((len = recv(sock, line, sizeof line, 0))) {
+	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;
+			return false;
 		}
 
-		if(!sptps_receive_data(&sptps, line, len))
-			return 1;
+		if(!sptps_receive_data(&mesh->sptps, mesh->line, len))
+			return false;
 	}
 
-	sptps_stop(&sptps);
+	sptps_stop(&mesh->sptps);
 	ecdsa_free(hiskey);
 	ecdsa_free(key);
-	closesocket(sock);
+	closesocket(mesh->sock);
 
-	if(!success) {
+	if(!mesh->success) {
 		fprintf(stderr, "Connection closed by peer, invitation cancelled.\n");
 		return false;
 	}