2 protocol_auth.c -- handle the meta-protocol, authentication
3 Copyright (C) 2014 Guus Sliepen <guus@meshlink.io>
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License along
16 with this program; if not, write to the Free Software Foundation, Inc.,
17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
23 #include "connection.h"
28 #include "meshlink_internal.h"
38 #include "ed25519/sha512.h"
42 extern bool node_write_devclass(meshlink_handle_t *mesh, node_t *n);
44 static bool send_proxyrequest(meshlink_handle_t *mesh, connection_t *c) {
45 switch(mesh->proxytype) {
50 sockaddr2str(&c->address, &host, &port);
51 send_request(mesh, c, "CONNECT %s:%s HTTP/1.1\r\n\r", host, port);
57 if(c->address.sa.sa_family != AF_INET) {
58 logger(mesh, MESHLINK_ERROR, "Cannot connect to an IPv6 host through a SOCKS 4 proxy!");
61 char s4req[9 + (mesh->proxyuser ? strlen(mesh->proxyuser) : 0)];
64 memcpy(s4req + 2, &c->address.in.sin_port, 2);
65 memcpy(s4req + 4, &c->address.in.sin_addr, 4);
67 memcpy(s4req + 8, mesh->proxyuser, strlen(mesh->proxyuser));
68 s4req[sizeof s4req - 1] = 0;
70 return send_meta(mesh, c, s4req, sizeof s4req);
73 int len = 3 + 6 + (c->address.sa.sa_family == AF_INET ? 4 : 16);
76 len += 3 + strlen(mesh->proxyuser) + strlen(mesh->proxypass);
84 s5req[i++] = strlen(mesh->proxyuser);
85 memcpy(s5req + i, mesh->proxyuser, strlen(mesh->proxyuser));
86 i += strlen(mesh->proxyuser);
87 s5req[i++] = strlen(mesh->proxypass);
88 memcpy(s5req + i, mesh->proxypass, strlen(mesh->proxypass));
89 i += strlen(mesh->proxypass);
96 if(c->address.sa.sa_family == AF_INET) {
98 memcpy(s5req + i, &c->address.in.sin_addr, 4);
100 memcpy(s5req + i, &c->address.in.sin_port, 2);
103 } else if(c->address.sa.sa_family == AF_INET6) {
105 memcpy(s5req + i, &c->address.in6.sin6_addr, 16);
107 memcpy(s5req + i, &c->address.in6.sin6_port, 2);
111 logger(mesh, MESHLINK_ERROR, "Address family %hx not supported for SOCKS 5 proxies!", c->address.sa.sa_family);
116 return send_meta(mesh, c, s5req, sizeof s5req);
119 logger(mesh, MESHLINK_ERROR, "Proxy type not implemented yet");
124 logger(mesh, MESHLINK_ERROR, "Unknown proxy type");
129 bool send_id(meshlink_handle_t *mesh, connection_t *c) {
131 int minor = mesh->self->connection->protocol_minor;
133 if(mesh->proxytype && c->outgoing)
134 if(!send_proxyrequest(mesh, c))
137 return send_request(mesh, c, "%d %s %d.%d", ID, mesh->self->connection->name, mesh->self->connection->protocol_major, minor);
140 static bool finalize_invitation(meshlink_handle_t *mesh, connection_t *c, const void *data, uint16_t len) {
141 if(strchr(data, '\n')) {
142 logger(mesh, MESHLINK_ERROR, "Received invalid key from invited node %s (%s)!\n", c->name, c->hostname);
146 // Create a new host config file
147 char filename[PATH_MAX];
148 snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, c->name);
149 if(!access(filename, F_OK)) {
150 logger(mesh, MESHLINK_ERROR, "Host config file for %s (%s) already exists!\n", c->name, c->hostname);
154 FILE *f = fopen(filename, "w");
156 logger(mesh, MESHLINK_ERROR, "Error trying to create %s: %s\n", filename, strerror(errno));
160 fprintf(f, "ECDSAPublicKey = %s\n", (const char *)data);
163 logger(mesh, MESHLINK_INFO, "Key succesfully received from %s (%s)", c->name, c->hostname);
165 //TODO: callback to application to inform of an accepted invitation
167 sptps_send_record(&c->sptps, 2, data, 0);
169 load_all_nodes(mesh);
174 static bool receive_invitation_sptps(void *handle, uint8_t type, const void *data, uint16_t len) {
175 connection_t *c = handle;
176 meshlink_handle_t *mesh = c->mesh;
181 if(type == 1 && c->status.invitation_used)
182 return finalize_invitation(mesh, c, data, len);
184 if(type != 0 || len != 18 || c->status.invitation_used)
187 // Recover the filename from the cookie and the key
188 char *fingerprint = ecdsa_get_base64_public_key(mesh->invitation_key);
190 char hashbuf[18 + strlen(fingerprint)];
192 memcpy(hashbuf, data, 18);
193 memcpy(hashbuf + 18, fingerprint, sizeof hashbuf - 18);
194 sha512(hashbuf, sizeof hashbuf, hash);
195 b64encode_urlsafe(hash, cookie, 18);
198 char filename[PATH_MAX], usedname[PATH_MAX];
199 snprintf(filename, sizeof filename, "%s" SLASH "invitations" SLASH "%s", mesh->confbase, cookie);
200 snprintf(usedname, sizeof usedname, "%s" SLASH "invitations" SLASH "%s.used", mesh->confbase, cookie);
202 // Atomically rename the invitation file
203 if(rename(filename, usedname)) {
205 logger(mesh, MESHLINK_ERROR, "Peer %s tried to use non-existing invitation %s\n", c->hostname, cookie);
207 logger(mesh, MESHLINK_ERROR, "Error trying to rename invitation %s\n", cookie);
211 // Open the renamed file
212 FILE *f = fopen(usedname, "r");
214 logger(mesh, MESHLINK_ERROR, "Error trying to open invitation %s\n", cookie);
218 // Read the new node's Name from the file
220 fgets(buf, sizeof buf, f);
222 buf[strlen(buf) - 1] = 0;
224 len = strcspn(buf, " \t=");
225 char *name = buf + len;
226 name += strspn(name, " \t");
229 name += strspn(name, " \t");
233 if(!*buf || !*name || strcasecmp(buf, "Name") || !check_id(name)) {
234 logger(mesh, MESHLINK_ERROR, "Invalid invitation file %s\n", cookie);
240 c->name = xstrdup(name);
242 // Send the node the contents of the invitation file
245 while((result = fread(buf, 1, sizeof buf, f)))
246 sptps_send_record(&c->sptps, 0, buf, result);
247 sptps_send_record(&c->sptps, 1, buf, 0);
251 c->status.invitation_used = true;
253 logger(mesh, MESHLINK_INFO, "Invitation %s succesfully sent to %s (%s)", cookie, c->name, c->hostname);
257 bool id_h(meshlink_handle_t *mesh, connection_t *c, const char *request) {
258 char name[MAX_STRING_SIZE];
260 if(sscanf(request, "%*d " MAX_STRING " %d.%d", name, &c->protocol_major, &c->protocol_minor) < 2) {
261 logger(mesh, MESHLINK_ERROR, "Got bad %s from %s (%s)", "ID", c->name,
266 /* Check if this is an invitation */
269 if(!mesh->invitation_key) {
270 logger(mesh, MESHLINK_ERROR, "Got invitation from %s but we don't have an invitation key", c->hostname);
274 c->ecdsa = ecdsa_set_base64_public_key(name + 1);
276 logger(mesh, MESHLINK_ERROR, "Got bad invitation from %s", c->hostname);
280 c->status.invitation = true;
281 char *mykey = ecdsa_get_base64_public_key(mesh->invitation_key);
284 if(!send_request(mesh, c, "%d %s", ACK, mykey))
288 c->protocol_minor = 2;
289 c->allow_request = 1;
291 return sptps_start(&c->sptps, c, false, false, mesh->invitation_key, c->ecdsa, meshlink_invitation_label, sizeof meshlink_invitation_label, send_meta_sptps, receive_invitation_sptps);
294 /* Check if identity is a valid name */
296 if(!check_id(name)) {
297 logger(mesh, MESHLINK_ERROR, "Got bad %s from %s (%s): %s", "ID", c->name,
298 c->hostname, "invalid name");
302 /* If this is an outgoing connection, make sure we are connected to the right host */
305 if(strcmp(c->name, name)) {
306 logger(mesh, MESHLINK_ERROR, "Peer %s is %s instead of %s", c->hostname, name,
313 c->name = xstrdup(name);
316 /* Check if version matches */
318 if(c->protocol_major != mesh->self->connection->protocol_major) {
319 logger(mesh, MESHLINK_ERROR, "Peer %s (%s) uses incompatible version %d.%d",
320 c->name, c->hostname, c->protocol_major, c->protocol_minor);
324 if(!c->config_tree) {
325 init_configuration(&c->config_tree);
327 if(!read_host_config(mesh, c->config_tree, c->name)) {
328 logger(mesh, MESHLINK_ERROR, "Peer %s had unknown identity (%s)", c->hostname, c->name);
333 read_ecdsa_public_key(mesh, c);
335 if(!ecdsa_active(c->ecdsa)) {
336 logger(mesh, MESHLINK_ERROR, "No key known for peer %s (%s)", c->name, c->hostname);
338 node_t *n = lookup_node(mesh, c->name);
339 if(n && !n->status.waitingforkey) {
340 logger(mesh, MESHLINK_INFO, "Requesting key from peer %s (%s)", c->name, c->hostname);
341 send_req_key(mesh, n);
347 /* Forbid version rollback for nodes whose ECDSA key we know */
349 if(ecdsa_active(c->ecdsa) && c->protocol_minor < 2) {
350 logger(mesh, MESHLINK_ERROR, "Peer %s (%s) tries to roll back protocol version to %d.%d",
351 c->name, c->hostname, c->protocol_major, c->protocol_minor);
355 c->allow_request = ACK;
356 char label[sizeof meshlink_tcp_label + strlen(mesh->self->name) + strlen(c->name) + 2];
359 snprintf(label, sizeof label, "%s %s %s", meshlink_tcp_label, mesh->self->name, c->name);
361 snprintf(label, sizeof label, "%s %s %s", meshlink_tcp_label, c->name, mesh->self->name);
363 return sptps_start(&c->sptps, c, c->outgoing, false, mesh->self->connection->ecdsa, c->ecdsa, label, sizeof label - 1, send_meta_sptps, receive_meta_sptps);
366 bool send_ack(meshlink_handle_t *mesh, connection_t *c) {
368 /* Check some options */
370 if(mesh->self->options & OPTION_PMTU_DISCOVERY)
371 c->options |= OPTION_PMTU_DISCOVERY;
373 return send_request(mesh, c, "%d %s %d %x", ACK, mesh->myport, mesh->devclass, (c->options & 0xffffff) | (PROT_MINOR << 24));
376 static void send_everything(meshlink_handle_t *mesh, connection_t *c) {
377 /* Send all known subnets and edges */
379 for splay_each(node_t, n, mesh->nodes) {
380 for splay_each(edge_t, e, n->edge_tree)
381 send_add_edge(mesh, c, e);
385 bool ack_h(meshlink_handle_t *mesh, connection_t *c, const char *request) {
386 char hisport[MAX_STRING_SIZE];
392 if(sscanf(request, "%*d " MAX_STRING " %d %x", hisport, &devclass, &options) != 3) {
393 logger(mesh, MESHLINK_ERROR, "Got bad %s from %s (%s)", "ACK", c->name,
398 if(devclass < 0 || devclass > _DEV_CLASS_MAX) {
399 logger(mesh, MESHLINK_ERROR, "Got bad %s from %s (%s): %s", "ACK", c->name,
400 c->hostname, "devclass invalid");
404 /* Check if we already have a node_t for him */
406 n = lookup_node(mesh, c->name);
410 n->name = xstrdup(c->name);
414 /* Oh dear, we already have a connection to this node. */
415 logger(mesh, MESHLINK_DEBUG, "Established a second connection with %s (%s), closing old connection", n->connection->name, n->connection->hostname);
417 if(n->connection->outgoing) {
419 logger(mesh, MESHLINK_WARNING, "Two outgoing connections to the same node!");
421 c->outgoing = n->connection->outgoing;
423 n->connection->outgoing = NULL;
426 terminate_connection(mesh, n->connection, false);
427 /* Run graph algorithm to keep things in sync */
432 n->devclass = devclass;
433 node_write_devclass(mesh, n);
435 n->last_successfull_connection = time(NULL);
439 if(!(c->options & options & OPTION_PMTU_DISCOVERY)) {
440 c->options &= ~OPTION_PMTU_DISCOVERY;
441 options &= ~OPTION_PMTU_DISCOVERY;
443 c->options |= options;
445 /* Activate this connection */
447 c->allow_request = ALL;
448 c->status.active = true;
450 logger(mesh, MESHLINK_INFO, "Connection with %s (%s) activated", c->name,
453 /* Send him everything we know */
455 send_everything(mesh, c);
457 /* Create an edge_t for this connection */
459 assert(devclass >= 0 && devclass <= _DEV_CLASS_MAX);
461 c->edge = new_edge();
462 c->edge->from = mesh->self;
464 sockaddr2str(&c->address, &hisaddress, NULL);
465 c->edge->address = str2sockaddr(hisaddress, hisport);
467 c->edge->weight = dev_class_traits[devclass].edge_weight;
468 c->edge->connection = c;
469 c->edge->options = c->options;
471 edge_add(mesh, c->edge);
473 /* Notify everyone of the new edge */
475 send_add_edge(mesh, mesh->everyone, c->edge);
477 /* Run MST and SSSP algorithms */