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"
40 static bool send_proxyrequest(meshlink_handle_t *mesh, connection_t *c) {
41 switch(mesh->proxytype) {
46 sockaddr2str(&c->address, &host, &port);
47 send_request(mesh, c, "CONNECT %s:%s HTTP/1.1\r\n\r", host, port);
53 if(c->address.sa.sa_family != AF_INET) {
54 logger(DEBUG_ALWAYS, LOG_ERR, "Cannot connect to an IPv6 host through a SOCKS 4 proxy!");
57 char s4req[9 + (mesh->proxyuser ? strlen(mesh->proxyuser) : 0)];
60 memcpy(s4req + 2, &c->address.in.sin_port, 2);
61 memcpy(s4req + 4, &c->address.in.sin_addr, 4);
63 memcpy(s4req + 8, mesh->proxyuser, strlen(mesh->proxyuser));
64 s4req[sizeof s4req - 1] = 0;
66 return send_meta(mesh, c, s4req, sizeof s4req);
69 int len = 3 + 6 + (c->address.sa.sa_family == AF_INET ? 4 : 16);
72 len += 3 + strlen(mesh->proxyuser) + strlen(mesh->proxypass);
80 s5req[i++] = strlen(mesh->proxyuser);
81 memcpy(s5req + i, mesh->proxyuser, strlen(mesh->proxyuser));
82 i += strlen(mesh->proxyuser);
83 s5req[i++] = strlen(mesh->proxypass);
84 memcpy(s5req + i, mesh->proxypass, strlen(mesh->proxypass));
85 i += strlen(mesh->proxypass);
93 if(c->address.sa.sa_family == AF_INET) {
95 memcpy(s5req + i, &c->address.in.sin_addr, 4);
97 memcpy(s5req + i, &c->address.in.sin_port, 2);
100 } else if(c->address.sa.sa_family == AF_INET6) {
102 memcpy(s5req + i, &c->address.in6.sin6_addr, 16);
104 memcpy(s5req + i, &c->address.in6.sin6_port, 2);
108 logger(DEBUG_ALWAYS, LOG_ERR, "Address family %hx not supported for SOCKS 5 proxies!", c->address.sa.sa_family);
113 return send_meta(mesh, c, s5req, sizeof s5req);
116 logger(DEBUG_ALWAYS, LOG_ERR, "Proxy type not implemented yet");
121 logger(DEBUG_ALWAYS, LOG_ERR, "Unknown proxy type");
126 bool send_id(meshlink_handle_t *mesh, connection_t *c) {
127 gettimeofday(&c->start, NULL);
129 int minor = mesh->self->connection->protocol_minor;
131 if(mesh->proxytype && c->outgoing)
132 if(!send_proxyrequest(mesh, c))
135 return send_request(mesh, c, "%d %s %d.%d", ID, mesh->self->connection->name, mesh->self->connection->protocol_major, minor);
138 static bool finalize_invitation(meshlink_handle_t *mesh, connection_t *c, const char *data, uint16_t len) {
139 if(strchr(data, '\n')) {
140 logger(DEBUG_ALWAYS, LOG_ERR, "Received invalid key from invited node %s (%s)!\n", c->name, c->hostname);
144 // Create a new host config file
145 char filename[PATH_MAX];
146 snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", mesh->confbase, c->name);
147 if(!access(filename, F_OK)) {
148 logger(DEBUG_ALWAYS, LOG_ERR, "Host config file for %s (%s) already exists!\n", c->name, c->hostname);
152 FILE *f = fopen(filename, "w");
154 logger(DEBUG_ALWAYS, LOG_ERR, "Error trying to create %s: %s\n", filename, strerror(errno));
158 fprintf(f, "ECDSAPublicKey = %s\n", data);
161 logger(DEBUG_CONNECTIONS, LOG_INFO, "Key succesfully received from %s (%s)", c->name, c->hostname);
163 //TODO: callback to application to inform of an accepted invitation
165 sptps_send_record(&c->sptps, 2, data, 0);
169 static bool receive_invitation_sptps(void *handle, uint8_t type, const char *data, uint16_t len) {
170 connection_t *c = handle;
171 meshlink_handle_t *mesh = c->mesh;
176 if(type == 1 && c->status.invitation_used)
177 return finalize_invitation(mesh, c, data, len);
179 if(type != 0 || len != 18 || c->status.invitation_used)
182 // Recover the filename from the cookie and the key
183 char *fingerprint = ecdsa_get_base64_public_key(mesh->invitation_key);
185 char hashbuf[18 + strlen(fingerprint)];
187 memcpy(hashbuf, data, 18);
188 memcpy(hashbuf + 18, fingerprint, sizeof hashbuf - 18);
189 sha512(hashbuf, sizeof hashbuf, hash);
190 b64encode_urlsafe(hash, cookie, 18);
193 char filename[PATH_MAX], usedname[PATH_MAX];
194 snprintf(filename, sizeof filename, "%s" SLASH "invitations" SLASH "%s", mesh->confbase, cookie);
195 snprintf(usedname, sizeof usedname, "%s" SLASH "invitations" SLASH "%s.used", mesh->confbase, cookie);
197 // Atomically rename the invitation file
198 if(rename(filename, usedname)) {
200 logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s tried to use non-existing invitation %s\n", c->hostname, cookie);
202 logger(DEBUG_ALWAYS, LOG_ERR, "Error trying to rename invitation %s\n", cookie);
206 // Open the renamed file
207 FILE *f = fopen(usedname, "r");
209 logger(DEBUG_ALWAYS, LOG_ERR, "Error trying to open invitation %s\n", cookie);
213 // Read the new node's Name from the file
215 fgets(buf, sizeof buf, f);
217 buf[strlen(buf) - 1] = 0;
219 len = strcspn(buf, " \t=");
220 char *name = buf + len;
221 name += strspn(name, " \t");
224 name += strspn(name, " \t");
228 if(!*buf || !*name || strcasecmp(buf, "Name") || !check_id(name)) {
229 logger(DEBUG_ALWAYS, LOG_ERR, "Invalid invitation file %s\n", cookie);
235 c->name = xstrdup(name);
237 // Send the node the contents of the invitation file
240 while((result = fread(buf, 1, sizeof buf, f)))
241 sptps_send_record(&c->sptps, 0, buf, result);
242 sptps_send_record(&c->sptps, 1, buf, 0);
246 c->status.invitation_used = true;
248 logger(DEBUG_CONNECTIONS, LOG_INFO, "Invitation %s succesfully sent to %s (%s)", cookie, c->name, c->hostname);
252 bool id_h(meshlink_handle_t *mesh, connection_t *c, const char *request) {
253 char name[MAX_STRING_SIZE];
255 if(sscanf(request, "%*d " MAX_STRING " %d.%d", name, &c->protocol_major, &c->protocol_minor) < 2) {
256 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "ID", c->name,
261 /* Check if this is an invitation */
264 if(!mesh->invitation_key) {
265 logger(DEBUG_ALWAYS, LOG_ERR, "Got invitation from %s but we don't have an invitation key", c->hostname);
269 c->ecdsa = ecdsa_set_base64_public_key(name + 1);
271 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad invitation from %s", c->hostname);
275 c->status.invitation = true;
276 char *mykey = ecdsa_get_base64_public_key(mesh->invitation_key);
279 if(!send_request(mesh, c, "%d %s", ACK, mykey))
283 c->protocol_minor = 2;
285 return sptps_start(&c->sptps, c, false, false, mesh->invitation_key, c->ecdsa, "tinc invitation", 15, send_meta_sptps, receive_invitation_sptps);
288 /* Check if identity is a valid name */
290 if(!check_id(name)) {
291 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "ID", c->name,
292 c->hostname, "invalid name");
296 /* If this is an outgoing connection, make sure we are connected to the right host */
299 if(strcmp(c->name, name)) {
300 logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s is %s instead of %s", c->hostname, name,
307 c->name = xstrdup(name);
310 /* Check if version matches */
312 if(c->protocol_major != mesh->self->connection->protocol_major) {
313 logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s (%s) uses incompatible version %d.%d",
314 c->name, c->hostname, c->protocol_major, c->protocol_minor);
318 if(!c->config_tree) {
319 init_configuration(&c->config_tree);
321 if(!read_host_config(mesh, c->config_tree, c->name)) {
322 logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s had unknown identity (%s)", c->hostname, c->name);
326 read_ecdsa_public_key(mesh, c);
328 if(c->protocol_minor && !ecdsa_active(c->ecdsa))
329 c->protocol_minor = 1;
332 /* Forbid version rollback for nodes whose ECDSA key we know */
334 if(ecdsa_active(c->ecdsa) && c->protocol_minor < 2) {
335 logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s (%s) tries to roll back protocol version to %d.%d",
336 c->name, c->hostname, c->protocol_major, c->protocol_minor);
340 c->allow_request = ACK;
341 char label[25 + strlen(mesh->self->name) + strlen(c->name)];
344 snprintf(label, sizeof label, "tinc TCP key expansion %s %s", mesh->self->name, c->name);
346 snprintf(label, sizeof label, "tinc TCP key expansion %s %s", c->name, mesh->self->name);
348 return sptps_start(&c->sptps, c, c->outgoing, false, mesh->self->connection->ecdsa, c->ecdsa, label, sizeof label, send_meta_sptps, receive_meta_sptps);
351 bool send_ack(meshlink_handle_t *mesh, connection_t *c) {
352 /* ACK message contains rest of the information the other end needs
353 to create node_t and edge_t structures. */
358 /* Estimate weight */
360 gettimeofday(&now, NULL);
361 c->estimated_weight = (now.tv_sec - c->start.tv_sec) * 1000 + (now.tv_usec - c->start.tv_usec) / 1000;
363 /* Check some options */
365 if(mesh->self->options & OPTION_PMTU_DISCOVERY)
366 c->options |= OPTION_PMTU_DISCOVERY;
368 return send_request(mesh, c, "%d %s %d %x", ACK, mesh->myport, c->estimated_weight, (c->options & 0xffffff) | (PROT_MINOR << 24));
371 static void send_everything(meshlink_handle_t *mesh, connection_t *c) {
372 /* Send all known subnets and edges */
374 for splay_each(node_t, n, mesh->nodes) {
375 for splay_each(edge_t, e, n->edge_tree)
376 send_add_edge(mesh, c, e);
380 bool ack_h(meshlink_handle_t *mesh, connection_t *c, const char *request) {
381 char hisport[MAX_STRING_SIZE];
388 if(sscanf(request, "%*d " MAX_STRING " %d %x", hisport, &weight, &options) != 3) {
389 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "ACK", c->name,
394 /* Check if we already have a node_t for him */
396 n = lookup_node(mesh, c->name);
400 n->name = xstrdup(c->name);
404 /* Oh dear, we already have a connection to this node. */
405 logger(DEBUG_CONNECTIONS, LOG_DEBUG, "Established a second connection with %s (%s), closing old connection", n->connection->name, n->connection->hostname);
407 if(n->connection->outgoing) {
409 logger(DEBUG_ALWAYS, LOG_WARNING, "Two outgoing connections to the same node!");
411 c->outgoing = n->connection->outgoing;
413 n->connection->outgoing = NULL;
416 terminate_connection(mesh, n->connection, false);
417 /* Run graph algorithm to keep things in sync */
424 if(!(c->options & options & OPTION_PMTU_DISCOVERY)) {
425 c->options &= ~OPTION_PMTU_DISCOVERY;
426 options &= ~OPTION_PMTU_DISCOVERY;
428 c->options |= options;
430 /* Activate this connection */
432 c->allow_request = ALL;
433 c->status.active = true;
435 logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Connection with %s (%s) activated", c->name,
438 /* Send him everything we know */
440 send_everything(mesh, c);
442 /* Create an edge_t for this connection */
444 c->edge = new_edge();
445 c->edge->from = mesh->self;
447 sockaddr2str(&c->address, &hisaddress, NULL);
448 c->edge->address = str2sockaddr(hisaddress, hisport);
450 c->edge->weight = (weight + c->estimated_weight) / 2;
451 c->edge->connection = c;
452 c->edge->options = c->options;
454 edge_add(mesh, c->edge);
456 /* Notify everyone of the new edge */
458 send_add_edge(mesh, mesh->everyone, c->edge);
460 /* Run MST and SSSP algorithms */