/*
protocol_key.c -- handle the meta-protocol, key exchange
Copyright (C) 1999-2005 Ivo Timmermans,
- 2000-2013 Guus Sliepen <guus@tinc-vpn.org>
+ 2000-2014 Guus Sliepen <guus@tinc-vpn.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
static bool mykeyused = false;
void send_key_changed(void) {
+#ifndef DISABLE_LEGACY
send_request(everyone, "%d %x %s", KEY_CHANGED, rand(), myself->name);
/* Immediately send new keys to directly connected nodes to keep UDP mappings alive */
for list_each(connection_t, c, connection_list)
- if(c->status.active && c->node && c->node->status.reachable && !c->node->status.sptps)
+ if(c->edge && c->node && c->node->status.reachable && !c->node->status.sptps)
send_ans_key(c->node);
+#endif
/* Force key exchange for connections using SPTPS */
return true;
}
-static bool send_initial_sptps_data(void *handle, uint8_t type, const char *data, size_t len) {
+static bool send_sptps_data_myself(void *handle, uint8_t type, const void *data, size_t len) {
+ return send_sptps_data(handle, myself, type, data, len);
+}
+
+static bool send_initial_sptps_data(void *handle, uint8_t type, const void *data, size_t len) {
node_t *to = handle;
- to->sptps.send_data = send_sptps_data;
+ to->sptps.send_data = send_sptps_data_myself;
char buf[len * 4 / 3 + 5];
b64encode(data, buf, len);
return send_request(to->nexthop->connection, "%d %s %s %d %s", REQ_KEY, myself->name, to->name, REQ_KEY, buf);
bool send_req_key(node_t *to) {
if(to->status.sptps) {
if(!node_read_ecdsa_public_key(to)) {
- logger(DEBUG_PROTOCOL, LOG_DEBUG, "No ECDSA key known for %s (%s)", to->name, to->hostname);
+ logger(DEBUG_PROTOCOL, LOG_DEBUG, "No Ed25519 key known for %s (%s)", to->name, to->hostname);
send_request(to->nexthop->connection, "%d %s %s %d", REQ_KEY, myself->name, to->name, REQ_PUBKEY);
return true;
}
- if(to->sptps.label)
- logger(DEBUG_ALWAYS, LOG_DEBUG, "send_req_key(%s) called while sptps->label != NULL!", to->name);
-
char label[25 + strlen(myself->name) + strlen(to->name)];
snprintf(label, sizeof label, "tinc UDP key expansion %s %s", myself->name, to->name);
sptps_stop(&to->sptps);
/* REQ_KEY is overloaded to allow arbitrary requests to be routed between two nodes. */
-static bool req_key_ext_h(connection_t *c, const char *request, node_t *from, int reqno) {
+static bool req_key_ext_h(connection_t *c, const char *request, node_t *from, node_t *to, int reqno) {
+ /* If this is a SPTPS packet, see if sending UDP info helps.
+ Note that we only do this if we're the destination or the static relay;
+ otherwise every hop would initiate its own UDP info message, resulting in elevated chatter. */
+ if((reqno == REQ_KEY || reqno == SPTPS_PACKET) && to->via == myself)
+ send_udp_info(myself, from);
+
+ if(reqno == SPTPS_PACKET) {
+ /* This is a SPTPS data packet. */
+
+ char buf[MAX_STRING_SIZE];
+ int len;
+ if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, buf) != 1 || !(len = b64decode(buf, buf, strlen(buf)))) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s) to %s (%s): %s", "SPTPS_PACKET", from->name, from->hostname, to->name, to->hostname, "invalid SPTPS data");
+ return true;
+ }
+
+ if(to != myself) {
+ /* We don't just forward the request, because we want to use UDP if it's available. */
+ send_sptps_data(to, from, 0, buf, len);
+ try_tx(to, true);
+ } else {
+ /* The packet is for us */
+ if(!sptps_receive_data(&from->sptps, buf, len)) {
+ /* Uh-oh. It might be that the tunnel is stuck in some corrupted state,
+ so let's restart SPTPS in case that helps. But don't do that too often
+ to prevent storms. */
+ if(from->last_req_key < now.tv_sec - 10) {
+ logger(DEBUG_PROTOCOL, LOG_ERR, "Failed to decode TCP packet from %s (%s), restarting SPTPS", from->name, from->hostname);
+ send_req_key(from);
+ }
+ return true;
+ }
+ send_mtu_info(myself, from, MTU);
+ }
+
+ return true;
+ }
+
+ /* Requests that are not SPTPS data packets are forwarded as-is. */
+
+ if (to != myself)
+ return send_request(to->nexthop->connection, "%s", request);
+
+ /* The request is for us */
+
switch(reqno) {
case REQ_PUBKEY: {
+ if(!node_read_ecdsa_public_key(from)) {
+ /* Request their key *before* we send our key back. Otherwise the first SPTPS packet from them will get dropped. */
+ logger(DEBUG_PROTOCOL, LOG_DEBUG, "Preemptively requesting Ed25519 key for %s (%s)", from->name, from->hostname);
+ send_request(from->nexthop->connection, "%d %s %s %d", REQ_KEY, myself->name, from->name, REQ_PUBKEY);
+ }
char *pubkey = ecdsa_get_base64_public_key(myself->connection->ecdsa);
send_request(from->nexthop->connection, "%d %s %s %d %s", REQ_KEY, myself->name, from->name, ANS_PUBKEY, pubkey);
free(pubkey);
return true;
}
- logger(DEBUG_PROTOCOL, LOG_INFO, "Learned ECDSA public key from %s (%s)", from->name, from->hostname);
- append_config_file(from->name, "ECDSAPublicKey", pubkey);
+ logger(DEBUG_PROTOCOL, LOG_INFO, "Learned Ed25519 public key from %s (%s)", from->name, from->hostname);
+ append_config_file(from->name, "Ed25519PublicKey", pubkey);
return true;
}
case REQ_KEY: {
if(!node_read_ecdsa_public_key(from)) {
- logger(DEBUG_PROTOCOL, LOG_DEBUG, "No ECDSA key known for %s (%s)", from->name, from->hostname);
+ logger(DEBUG_PROTOCOL, LOG_DEBUG, "No Ed25519 key known for %s (%s)", from->name, from->hostname);
send_request(from->nexthop->connection, "%d %s %s %d", REQ_KEY, myself->name, from->name, REQ_PUBKEY);
return true;
}
from->status.validkey = false;
from->status.waitingforkey = true;
from->last_req_key = now.tv_sec;
- sptps_start(&from->sptps, from, false, true, myself->connection->ecdsa, from->ecdsa, label, sizeof label, send_sptps_data, receive_sptps_record);
- sptps_receive_data(&from->sptps, buf, len);
- return true;
- }
-
- case REQ_SPTPS: {
- if(!from->status.validkey) {
- logger(DEBUG_PROTOCOL, LOG_ERR, "Got REQ_SPTPS from %s (%s) but we don't have a valid key yet", from->name, from->hostname);
- return true;
- }
-
- char buf[MAX_STRING_SIZE];
- int len;
- if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, buf) != 1 || !(len = b64decode(buf, buf, strlen(buf)))) {
- logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "REQ_SPTPS", from->name, from->hostname, "invalid SPTPS data");
- return true;
- }
+ sptps_start(&from->sptps, from, false, true, myself->connection->ecdsa, from->ecdsa, label, sizeof label, send_sptps_data_myself, receive_sptps_record);
sptps_receive_data(&from->sptps, buf, len);
+ send_mtu_info(myself, from, MTU);
return true;
}
if(to == myself) { /* Yes */
/* Is this an extended REQ_KEY message? */
if(experimental && reqno)
- return req_key_ext_h(c, request, from, reqno);
+ return req_key_ext_h(c, request, from, to, reqno);
/* No, just send our key back */
send_ans_key(from);
return true;
}
+ /* Is this an extended REQ_KEY message? */
+ if(experimental && reqno)
+ return req_key_ext_h(c, request, from, to, reqno);
+
send_request(to->nexthop->connection, "%s", request);
}
if(to->status.sptps)
abort();
- size_t keylen = cipher_keylength(myself->incipher);
+#ifdef DISABLE_LEGACY
+ return false;
+#else
+ size_t keylen = myself->incipher ? cipher_keylength(myself->incipher) : 1;
char key[keylen * 2 + 1];
+ randomize(key, keylen);
+
cipher_close(to->incipher);
digest_close(to->indigest);
- to->incipher = cipher_open_by_nid(cipher_get_nid(myself->incipher));
- to->indigest = digest_open_by_nid(digest_get_nid(myself->indigest), digest_length(myself->indigest));
- to->incompression = myself->incompression;
+ if(myself->incipher) {
+ to->incipher = cipher_open_by_nid(cipher_get_nid(myself->incipher));
+ if(!to->incipher)
+ abort();
+ if(!cipher_set_key(to->incipher, key, false))
+ abort();
+ }
- if(!to->incipher || !to->indigest)
- abort();
+ if(myself->indigest) {
+ to->indigest = digest_open_by_nid(digest_get_nid(myself->indigest), digest_length(myself->indigest));
+ if(!to->indigest)
+ abort();
+ if(!digest_set_key(to->indigest, key, keylen))
+ abort();
+ }
- randomize(key, keylen);
- if(!cipher_set_key(to->incipher, key, false))
- abort();
- if(!digest_set_key(to->indigest, key, keylen))
- abort();
+ to->incompression = myself->incompression;
bin2hex(key, key, keylen);
to->received = 0;
if(replaywin) memset(to->late, 0, replaywin);
+ to->status.validkey_in = true;
+
return send_request(to->nexthop->connection, "%d %s %s %s %d %d %d %d", ANS_KEY,
myself->name, to->name, key,
cipher_get_nid(to->incipher),
digest_get_nid(to->indigest),
(int)digest_length(to->indigest),
to->incompression);
+#endif
}
bool ans_key_h(connection_t *c, const char *request) {
return send_request(to->nexthop->connection, "%s", request);
}
+#ifndef DISABLE_LEGACY
/* Don't use key material until every check has passed. */
cipher_close(from->outcipher);
digest_close(from->outdigest);
+#endif
from->status.validkey = false;
if(compression < 0 || compression > 11) {
if(from->status.sptps) {
char buf[strlen(key)];
int len = b64decode(key, buf, strlen(key));
-
- if(!len || !sptps_receive_data(&from->sptps, buf, len))
- logger(DEBUG_ALWAYS, LOG_ERR, "Error processing SPTPS data from %s (%s)", from->name, from->hostname);
+ if(!len || !sptps_receive_data(&from->sptps, buf, len)) {
+ /* Uh-oh. It might be that the tunnel is stuck in some corrupted state,
+ so let's restart SPTPS in case that helps. But don't do that too often
+ to prevent storms.
+ Note that simply relying on handshake timeout is not enough, because
+ that doesn't apply to key regeneration. */
+ if(from->last_req_key < now.tv_sec - 10) {
+ logger(DEBUG_PROTOCOL, LOG_ERR, "Failed to decode handshake TCP packet from %s (%s), restarting SPTPS", from->name, from->hostname);
+ send_req_key(from);
+ }
+ return true;
+ }
if(from->status.validkey) {
if(*address && *port) {
sockaddr_t sa = str2sockaddr(address, port);
update_node_udp(from, &sa);
}
-
- if(from->options & OPTION_PMTU_DISCOVERY && !(from->options & OPTION_TCPONLY))
- send_mtu_probe(from);
}
+ send_mtu_info(myself, from, MTU);
+
return true;
}
+#ifdef DISABLE_LEGACY
+ logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses legacy protocol!", from->name, from->hostname);
+ return false;
+#else
/* Check and lookup cipher and digest algorithms */
- if(!(from->outcipher = cipher_open_by_nid(cipher))) {
- logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses unknown cipher!", from->name, from->hostname);
- return false;
+ if(cipher) {
+ if(!(from->outcipher = cipher_open_by_nid(cipher))) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses unknown cipher!", from->name, from->hostname);
+ return false;
+ }
+ } else {
+ from->outcipher = NULL;
}
- if(!(from->outdigest = digest_open_by_nid(digest, maclength))) {
- logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses unknown digest!", from->name, from->hostname);
- return false;
+ if(digest) {
+ if(!(from->outdigest = digest_open_by_nid(digest, maclength))) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses unknown digest!", from->name, from->hostname);
+ return false;
+ }
+ } else {
+ from->outdigest = NULL;
}
if(maclength != digest_length(from->outdigest)) {
keylen = hex2bin(key, key, sizeof key);
- if(keylen != cipher_keylength(from->outcipher)) {
+ if(keylen != (from->outcipher ? cipher_keylength(from->outcipher) : 1)) {
logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses wrong keylength!", from->name, from->hostname);
return true;
}
/* Update our copy of the origin's packet key */
- if(!cipher_set_key(from->outcipher, key, true))
+ if(from->outcipher && !cipher_set_key(from->outcipher, key, true))
return false;
- if(!digest_set_key(from->outdigest, key, keylen))
+ if(from->outdigest && !digest_set_key(from->outdigest, key, keylen))
return false;
from->status.validkey = true;
update_node_udp(from, &sa);
}
- if(from->options & OPTION_PMTU_DISCOVERY && !(from->options & OPTION_TCPONLY))
- send_mtu_probe(from);
-
return true;
+#endif
}
projects / tinc / blobdiff