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"
40 #include "ed25519/sha512.h"
42 ecdsa_t *invitation_key = NULL;
44 static bool send_proxyrequest(connection_t *c) {
50 sockaddr2str(&c->address, &host, &port);
51 send_request(c, "CONNECT %s:%s HTTP/1.1\r\n\r", host, port);
57 if(c->address.sa.sa_family != AF_INET) {
58 logger(DEBUG_ALWAYS, LOG_ERR, "Cannot connect to an IPv6 host through a SOCKS 4 proxy!");
61 char s4req[9 + (proxyuser ? strlen(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, proxyuser, strlen(proxyuser));
68 s4req[sizeof s4req - 1] = 0;
70 return send_meta(c, s4req, sizeof s4req);
73 int len = 3 + 6 + (c->address.sa.sa_family == AF_INET ? 4 : 16);
76 len += 3 + strlen(proxyuser) + strlen(proxypass);
84 s5req[i++] = strlen(proxyuser);
85 memcpy(s5req + i, proxyuser, strlen(proxyuser));
86 i += strlen(proxyuser);
87 s5req[i++] = strlen(proxypass);
88 memcpy(s5req + i, proxypass, strlen(proxypass));
89 i += strlen(proxypass);
97 if(c->address.sa.sa_family == AF_INET) {
99 memcpy(s5req + i, &c->address.in.sin_addr, 4);
101 memcpy(s5req + i, &c->address.in.sin_port, 2);
104 } else if(c->address.sa.sa_family == AF_INET6) {
106 memcpy(s5req + i, &c->address.in6.sin6_addr, 16);
108 memcpy(s5req + i, &c->address.in6.sin6_port, 2);
112 logger(DEBUG_ALWAYS, LOG_ERR, "Address family %hx not supported for SOCKS 5 proxies!", c->address.sa.sa_family);
117 return send_meta(c, s5req, sizeof s5req);
120 logger(DEBUG_ALWAYS, LOG_ERR, "Proxy type not implemented yet");
125 logger(DEBUG_ALWAYS, LOG_ERR, "Unknown proxy type");
130 bool send_id(connection_t *c) {
131 gettimeofday(&c->start, NULL);
133 int minor = myself->connection->protocol_minor;
135 if(proxytype && c->outgoing)
136 if(!send_proxyrequest(c))
139 return send_request(c, "%d %s %d.%d", ID, myself->connection->name, myself->connection->protocol_major, minor);
142 static bool finalize_invitation(connection_t *c, const char *data, uint16_t len) {
143 if(strchr(data, '\n')) {
144 logger(DEBUG_ALWAYS, LOG_ERR, "Received invalid key from invited node %s (%s)!\n", c->name, c->hostname);
148 // Create a new host config file
149 char filename[PATH_MAX];
150 snprintf(filename, sizeof filename, "%s" SLASH "hosts" SLASH "%s", confbase, c->name);
151 if(!access(filename, F_OK)) {
152 logger(DEBUG_ALWAYS, LOG_ERR, "Host config file for %s (%s) already exists!\n", c->name, c->hostname);
156 FILE *f = fopen(filename, "w");
158 logger(DEBUG_ALWAYS, LOG_ERR, "Error trying to create %s: %s\n", filename, strerror(errno));
162 fprintf(f, "ECDSAPublicKey = %s\n", data);
165 logger(DEBUG_CONNECTIONS, LOG_INFO, "Key succesfully received from %s (%s)", c->name, c->hostname);
167 //TODO: callback to application to inform of an accepted invitation
169 sptps_send_record(&c->sptps, 2, data, 0);
173 static bool receive_invitation_sptps(void *handle, uint8_t type, const char *data, uint16_t len) {
174 connection_t *c = handle;
179 if(type == 1 && c->status.invitation_used)
180 return finalize_invitation(c, data, len);
182 if(type != 0 || len != 18 || c->status.invitation_used)
185 // Recover the filename from the cookie and the key
186 char *fingerprint = ecdsa_get_base64_public_key(invitation_key);
188 char hashbuf[18 + strlen(fingerprint)];
190 memcpy(hashbuf, data, 18);
191 memcpy(hashbuf + 18, fingerprint, sizeof hashbuf - 18);
192 sha512(hashbuf, sizeof hashbuf, hash);
193 b64encode_urlsafe(hash, cookie, 18);
196 char filename[PATH_MAX], usedname[PATH_MAX];
197 snprintf(filename, sizeof filename, "%s" SLASH "invitations" SLASH "%s", confbase, cookie);
198 snprintf(usedname, sizeof usedname, "%s" SLASH "invitations" SLASH "%s.used", confbase, cookie);
200 // Atomically rename the invitation file
201 if(rename(filename, usedname)) {
203 logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s tried to use non-existing invitation %s\n", c->hostname, cookie);
205 logger(DEBUG_ALWAYS, LOG_ERR, "Error trying to rename invitation %s\n", cookie);
209 // Open the renamed file
210 FILE *f = fopen(usedname, "r");
212 logger(DEBUG_ALWAYS, LOG_ERR, "Error trying to open invitation %s\n", cookie);
216 // Read the new node's Name from the file
218 fgets(buf, sizeof buf, f);
220 buf[strlen(buf) - 1] = 0;
222 len = strcspn(buf, " \t=");
223 char *name = buf + len;
224 name += strspn(name, " \t");
227 name += strspn(name, " \t");
231 if(!*buf || !*name || strcasecmp(buf, "Name") || !check_id(name)) {
232 logger(DEBUG_ALWAYS, LOG_ERR, "Invalid invitation file %s\n", cookie);
238 c->name = xstrdup(name);
240 // Send the node the contents of the invitation file
243 while((result = fread(buf, 1, sizeof buf, f)))
244 sptps_send_record(&c->sptps, 0, buf, result);
245 sptps_send_record(&c->sptps, 1, buf, 0);
249 c->status.invitation_used = true;
251 logger(DEBUG_CONNECTIONS, LOG_INFO, "Invitation %s succesfully sent to %s (%s)", cookie, c->name, c->hostname);
255 bool id_h(connection_t *c, const char *request) {
256 char name[MAX_STRING_SIZE];
258 if(sscanf(request, "%*d " MAX_STRING " %d.%d", name, &c->protocol_major, &c->protocol_minor) < 2) {
259 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "ID", c->name,
264 /* Check if this is an invitation */
267 if(!invitation_key) {
268 logger(DEBUG_ALWAYS, LOG_ERR, "Got invitation from %s but we don't have an invitation key", c->hostname);
272 c->ecdsa = ecdsa_set_base64_public_key(name + 1);
274 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad invitation from %s", c->hostname);
278 c->status.invitation = true;
279 char *mykey = ecdsa_get_base64_public_key(invitation_key);
282 if(!send_request(c, "%d %s", ACK, mykey))
286 c->protocol_minor = 2;
288 return sptps_start(&c->sptps, c, false, false, invitation_key, c->ecdsa, "tinc invitation", 15, send_meta_sptps, receive_invitation_sptps);
291 /* Check if identity is a valid name */
293 if(!check_id(name)) {
294 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "ID", c->name,
295 c->hostname, "invalid name");
299 /* If this is an outgoing connection, make sure we are connected to the right host */
302 if(strcmp(c->name, name)) {
303 logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s is %s instead of %s", c->hostname, name,
310 c->name = xstrdup(name);
313 /* Check if version matches */
315 if(c->protocol_major != myself->connection->protocol_major) {
316 logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s (%s) uses incompatible version %d.%d",
317 c->name, c->hostname, c->protocol_major, c->protocol_minor);
321 if(bypass_security) {
323 init_configuration(&c->config_tree);
324 c->allow_request = ACK;
328 if(!c->config_tree) {
329 init_configuration(&c->config_tree);
331 if(!read_host_config(c->config_tree, c->name)) {
332 logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s had unknown identity (%s)", c->hostname, c->name);
336 read_ecdsa_public_key(c);
338 if(c->protocol_minor && !ecdsa_active(c->ecdsa))
339 c->protocol_minor = 1;
342 /* Forbid version rollback for nodes whose ECDSA key we know */
344 if(ecdsa_active(c->ecdsa) && c->protocol_minor < 2) {
345 logger(DEBUG_ALWAYS, LOG_ERR, "Peer %s (%s) tries to roll back protocol version to %d.%d",
346 c->name, c->hostname, c->protocol_major, c->protocol_minor);
350 c->allow_request = ACK;
351 char label[25 + strlen(myself->name) + strlen(c->name)];
354 snprintf(label, sizeof label, "tinc TCP key expansion %s %s", myself->name, c->name);
356 snprintf(label, sizeof label, "tinc TCP key expansion %s %s", c->name, myself->name);
358 return sptps_start(&c->sptps, c, c->outgoing, false, myself->connection->ecdsa, c->ecdsa, label, sizeof label, send_meta_sptps, receive_meta_sptps);
361 bool send_ack(connection_t *c) {
362 /* ACK message contains rest of the information the other end needs
363 to create node_t and edge_t structures. */
368 /* Estimate weight */
370 gettimeofday(&now, NULL);
371 c->estimated_weight = (now.tv_sec - c->start.tv_sec) * 1000 + (now.tv_usec - c->start.tv_usec) / 1000;
373 /* Check some options */
375 if(myself->options & OPTION_PMTU_DISCOVERY)
376 c->options |= OPTION_PMTU_DISCOVERY;
378 return send_request(c, "%d %s %d %x", ACK, myport, c->estimated_weight, (c->options & 0xffffff) | (PROT_MINOR << 24));
381 static void send_everything(connection_t *c) {
382 /* Send all known subnets and edges */
385 if(disablebuggypeers) {
388 char pad[MAXBUFSIZE - MAXSIZE];
391 memset(&zeropkt, 0, sizeof zeropkt);
392 zeropkt.pkt.len = MAXBUFSIZE;
393 send_tcppacket(c, &zeropkt.pkt);
396 for splay_each(node_t, n, node_tree) {
397 for splay_each(edge_t, e, n->edge_tree)
402 bool ack_h(connection_t *c, const char *request) {
403 char hisport[MAX_STRING_SIZE];
410 if(sscanf(request, "%*d " MAX_STRING " %d %x", hisport, &weight, &options) != 3) {
411 logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "ACK", c->name,
416 /* Check if we already have a node_t for him */
418 n = lookup_node(c->name);
422 n->name = xstrdup(c->name);
426 /* Oh dear, we already have a connection to this node. */
427 logger(DEBUG_CONNECTIONS, LOG_DEBUG, "Established a second connection with %s (%s), closing old connection", n->connection->name, n->connection->hostname);
429 if(n->connection->outgoing) {
431 logger(DEBUG_ALWAYS, LOG_WARNING, "Two outgoing connections to the same node!");
433 c->outgoing = n->connection->outgoing;
435 n->connection->outgoing = NULL;
438 terminate_connection(n->connection, false);
439 /* Run graph algorithm to keep things in sync */
446 if(!(c->options & options & OPTION_PMTU_DISCOVERY)) {
447 c->options &= ~OPTION_PMTU_DISCOVERY;
448 options &= ~OPTION_PMTU_DISCOVERY;
450 c->options |= options;
452 /* Activate this connection */
454 c->allow_request = ALL;
455 c->status.active = true;
457 logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Connection with %s (%s) activated", c->name,
460 /* Send him everything we know */
464 /* Create an edge_t for this connection */
466 c->edge = new_edge();
467 c->edge->from = myself;
469 sockaddr2str(&c->address, &hisaddress, NULL);
470 c->edge->address = str2sockaddr(hisaddress, hisport);
472 c->edge->weight = (weight + c->estimated_weight) / 2;
473 c->edge->connection = c;
474 c->edge->options = c->options;
478 /* Notify everyone of the new edge */
480 send_add_edge(everyone, c->edge);
482 /* Run MST and SSSP algorithms */