/*
protocol_key.c -- handle the meta-protocol, key exchange
- Copyright (C) 1999-2002 Ivo Timmermans <itimmermans@bigfoot.com>,
- 2000-2002 Guus Sliepen <guus@sliepen.warande.net>
+ Copyright (C) 1999-2005 Ivo Timmermans,
+ 2000-2017 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
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-
- $Id: protocol_key.c,v 1.1.4.6 2002/03/22 13:31:18 guus Exp $
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
-#include "config.h"
-
-#include <stdlib.h>
-#include <string.h>
-#include <syslog.h>
-#include <stdio.h>
-#include <stdarg.h>
-#include <errno.h>
-
-#include <utils.h>
-#include <xalloc.h>
-#include <avl_tree.h>
+#include "system.h"
-#include "conf.h"
+#include "cipher.h"
+#include "connection.h"
+#include "crypto.h"
+#include "logger.h"
#include "net.h"
#include "netutl.h"
-#include "protocol.h"
-#include "meta.h"
-#include "connection.h"
#include "node.h"
-#include "edge.h"
+#include "prf.h"
+#include "protocol.h"
+#include "sptps.h"
+#include "utils.h"
+#include "xalloc.h"
-#include "system.h"
+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->edge && c->node && c->node->status.reachable && !c->node->status.sptps)
+ send_ans_key(c->node);
+#endif
+
+ /* Force key exchange for connections using SPTPS */
+
+ if(experimental) {
+ for splay_each(node_t, n, node_tree)
+ if(n->status.reachable && n->status.validkey && n->status.sptps)
+ sptps_force_kex(&n->sptps);
+ }
+}
+
+bool key_changed_h(connection_t *c, const char *request) {
+ char name[MAX_STRING_SIZE];
+ node_t *n;
+
+ if(sscanf(request, "%*d %*x " MAX_STRING, name) != 1) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "KEY_CHANGED",
+ c->name, c->hostname);
+ return false;
+ }
+
+ if(seen_request(request))
+ return true;
+
+ n = lookup_node(name);
+
+ if(!n) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got %s from %s (%s) origin %s which does not exist",
+ "KEY_CHANGED", c->name, c->hostname, name);
+ return true;
+ }
+
+ if(!n->status.sptps) {
+ n->status.validkey = false;
+ n->last_req_key = 0;
+ }
+
+ /* Tell the others */
+
+ if(!tunnelserver)
+ forward_request(c, request);
-int mykeyused = 0;
-
-int send_key_changed(connection_t *c, node_t *n)
-{
- connection_t *other;
- avl_node_t *node;
-cp
- /* Only send this message if some other daemon requested our key previously.
- This reduces unnecessary key_changed broadcasts.
- */
-
- if(n == myself && !mykeyused)
- return 0;
-
- for(node = connection_tree->head; node; node = node->next)
- {
- other = (connection_t *)node->data;
- if(other->status.active && other != c)
- send_request(other, "%d %lx %s", KEY_CHANGED, random(), n->name);
- }
-cp
- return 0;
+ return true;
}
-int key_changed_h(connection_t *c)
-{
- char name[MAX_STRING_SIZE];
- avl_node_t *node;
- connection_t *other;
- node_t *n;
-cp
- if(sscanf(c->buffer, "%*d %*x "MAX_STRING, name) != 1)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "KEY_CHANGED",
- c->name, c->hostname);
- return -1;
- }
-
- if(seen_request(c->buffer))
- return 0;
-
- n = lookup_node(name);
-
- if(!n)
- {
- syslog(LOG_ERR, _("Got %s from %s (%s) origin %s which does not exist"), "KEY_CHANGED",
- c->name, c->hostname, name);
- return -1;
- }
-
- n->status.validkey = 0;
- n->status.waitingforkey = 0;
- n->sent_seqno = 0;
-
- /* Tell the others */
-
- for(node = connection_tree->head; node; node = node->next)
- {
- other = (connection_t *)node->data;
- if(other->status.active && other != c)
- send_request(other, "%s", c->buffer);
- }
-cp
- return 0;
+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);
}
-int send_req_key(connection_t *c, node_t *from, node_t *to)
-{
-cp
- return send_request(c, "%d %s %s", REQ_KEY,
- from->name, to->name);
+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_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);
}
-int req_key_h(connection_t *c)
-{
- char from_name[MAX_STRING_SIZE];
- char to_name[MAX_STRING_SIZE];
- node_t *from, *to;
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING" "MAX_STRING, from_name, to_name) != 2)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "REQ_KEY",
- c->name, c->hostname);
- return -1;
- }
-
- from = lookup_node(from_name);
-
- if(!from)
- {
- syslog(LOG_ERR, _("Got %s from %s (%s) origin %s which does not exist in our connection list"), "REQ_KEY",
- c->name, c->hostname, from_name);
- return -1;
- }
-
- to = lookup_node(to_name);
-
- if(!to)
- {
- syslog(LOG_ERR, _("Got %s from %s (%s) destination %s which does not exist in our connection list"), "REQ_KEY",
- c->name, c->hostname, to_name);
- return -1;
- }
-
- /* Check if this key request is for us */
-
- if(to == myself) /* Yes, send our own key back */
- {
- mykeyused = 1;
- from->received_seqno = 0;
- send_ans_key(c, myself, from);
- }
- else
- {
-/* Proxy keys
- if(to->status.validkey)
- {
- send_ans_key(c, to, from);
- }
- else
-*/
- send_req_key(to->nexthop->connection, from, to);
- }
+bool send_req_key(node_t *to) {
+ if(to->status.sptps) {
+ if(!node_read_ecdsa_public_key(to)) {
+ 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;
+ }
+
+ 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);
+ to->status.validkey = false;
+ to->status.waitingforkey = true;
+ to->last_req_key = now.tv_sec;
+ to->incompression = myself->incompression;
+ return sptps_start(&to->sptps, to, true, true, myself->connection->ecdsa, to->ecdsa, label, sizeof label, send_initial_sptps_data, receive_sptps_record);
+ }
-cp
- return 0;
+ return send_request(to->nexthop->connection, "%d %s %s", REQ_KEY, myself->name, to->name);
}
-int send_ans_key(connection_t *c, node_t *from, node_t *to)
-{
- char key[MAX_STRING_SIZE];
-cp
- bin2hex(from->key, key, from->keylength);
- key[from->keylength * 2] = '\0';
-cp
- return send_request(c, "%d %s %s %s %d %d %d %d", ANS_KEY,
- from->name, to->name, key, from->cipher?from->cipher->nid:0, from->digest?from->digest->type:0, from->maclength, from->compression);
+/* 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, 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;
+ }
+
+ case ANS_PUBKEY: {
+ if(node_read_ecdsa_public_key(from)) {
+ logger(DEBUG_PROTOCOL, LOG_WARNING, "Got ANS_PUBKEY from %s (%s) even though we already have his pubkey", from->name, from->hostname);
+ return true;
+ }
+
+ char pubkey[MAX_STRING_SIZE];
+ if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, pubkey) != 1 || !(from->ecdsa = ecdsa_set_base64_public_key(pubkey))) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "ANS_PUBKEY", from->name, from->hostname, "invalid pubkey");
+ return true;
+ }
+
+ 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 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;
+ }
+
+ if(from->sptps.label)
+ logger(DEBUG_ALWAYS, LOG_DEBUG, "Got REQ_KEY from %s while we already started a SPTPS session!", from->name);
+
+ 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_START", from->name, from->hostname, "invalid SPTPS data");
+ return true;
+ }
+
+ char label[25 + strlen(from->name) + strlen(myself->name)];
+ snprintf(label, sizeof label, "tinc UDP key expansion %s %s", from->name, myself->name);
+ sptps_stop(&from->sptps);
+ 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_myself, receive_sptps_record);
+ sptps_receive_data(&from->sptps, buf, len);
+ send_mtu_info(myself, from, MTU);
+ return true;
+ }
+
+ default:
+ logger(DEBUG_ALWAYS, LOG_ERR, "Unknown extended REQ_KEY request from %s (%s): %s", from->name, from->hostname, request);
+ return true;
+ }
}
-int ans_key_h(connection_t *c)
-{
- char from_name[MAX_STRING_SIZE];
- char to_name[MAX_STRING_SIZE];
- char key[MAX_STRING_SIZE];
- int cipher, digest, maclength, compression;
- node_t *from, *to;
-cp
- if(sscanf(c->buffer, "%*d "MAX_STRING" "MAX_STRING" "MAX_STRING" %d %d %d %d", from_name, to_name, key, &cipher, &digest, &maclength, &compression) != 7)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "ANS_KEY",
- c->name, c->hostname);
- return -1;
- }
-
- from = lookup_node(from_name);
-
- if(!from)
- {
- syslog(LOG_ERR, _("Got %s from %s (%s) origin %s which does not exist in our connection list"), "ANS_KEY",
- c->name, c->hostname, from_name);
- return -1;
- }
-
- to = lookup_node(to_name);
-
- if(!to)
- {
- syslog(LOG_ERR, _("Got %s from %s (%s) destination %s which does not exist in our connection list"), "ANS_KEY",
- c->name, c->hostname, to_name);
- return -1;
- }
-
- /* Forward it if necessary */
-
- if(to != myself)
- {
- return send_request(to->nexthop->connection, "%s", c->buffer);
- }
-
- /* Update our copy of the origin's packet key */
-
- if(from->key)
- free(from->key);
-
- from->key = xstrdup(key);
- from->keylength = strlen(key) / 2;
- hex2bin(from->key, from->key, from->keylength);
- from->key[from->keylength] = '\0';
-
- from->status.validkey = 1;
- from->status.waitingforkey = 0;
-
- /* Check and lookup cipher and digest algorithms */
-
- if(cipher)
- {
- from->cipher = EVP_get_cipherbynid(cipher);
- if(!from->cipher)
- {
- syslog(LOG_ERR, _("Node %s (%s) uses unknown cipher!"), from->name, from->hostname);
- return -1;
+bool req_key_h(connection_t *c, const char *request) {
+ char from_name[MAX_STRING_SIZE];
+ char to_name[MAX_STRING_SIZE];
+ node_t *from, *to;
+ int reqno = 0;
+
+ if(sscanf(request, "%*d " MAX_STRING " " MAX_STRING " %d", from_name, to_name, &reqno) < 2) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "REQ_KEY", c->name,
+ c->hostname);
+ return false;
+ }
+
+ if(!check_id(from_name) || !check_id(to_name)) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "REQ_KEY", c->name, c->hostname, "invalid name");
+ return false;
+ }
+
+ from = lookup_node(from_name);
+
+ if(!from) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got %s from %s (%s) origin %s which does not exist in our connection list",
+ "REQ_KEY", c->name, c->hostname, from_name);
+ return true;
}
- if(from->keylength != from->cipher->key_len + from->cipher->iv_len)
- {
- syslog(LOG_ERR, _("Node %s (%s) uses wrong keylength!"), from->name, from->hostname);
- return -1;
- }
- }
- else
- {
- from->cipher = NULL;
- }
-
- from->maclength = maclength;
-
- if(digest)
- {
- from->digest = EVP_get_digestbynid(digest);
- if(!from->digest)
- {
- syslog(LOG_ERR, _("Node %s (%s) uses unknown digest!"), from->name, from->hostname);
- return -1;
+
+ to = lookup_node(to_name);
+
+ if(!to) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got %s from %s (%s) destination %s which does not exist in our connection list",
+ "REQ_KEY", c->name, c->hostname, to_name);
+ return true;
}
- if(from->maclength > from->digest->md_size || from->maclength < 0)
- {
- syslog(LOG_ERR, _("Node %s (%s) uses bogus MAC length!"), from->name, from->hostname);
- return -1;
+
+ /* Check if this key request is for us */
+
+ if(to == myself) { /* Yes */
+ /* Is this an extended REQ_KEY message? */
+ if(experimental && reqno)
+ return req_key_ext_h(c, request, from, to, reqno);
+
+ /* No, just send our key back */
+ send_ans_key(from);
+ } else {
+ if(tunnelserver)
+ return true;
+
+ if(!to->status.reachable) {
+ logger(DEBUG_PROTOCOL, LOG_WARNING, "Got %s from %s (%s) destination %s which is not reachable",
+ "REQ_KEY", c->name, c->hostname, to_name);
+ 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);
}
- }
- else
- {
- from->digest = NULL;
- }
-
- from->compression = compression;
-
- flush_queue(from);
-cp
- return 0;
+
+ return true;
+}
+
+bool send_ans_key(node_t *to) {
+ if(to->status.sptps)
+ abort();
+
+#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);
+
+ 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(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();
+ }
+
+ to->incompression = myself->incompression;
+
+ bin2hex(key, key, keylen);
+
+ // Reset sequence number and late packet window
+ mykeyused = true;
+ to->received_seqno = 0;
+ 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) {
+ char from_name[MAX_STRING_SIZE];
+ char to_name[MAX_STRING_SIZE];
+ char key[MAX_STRING_SIZE];
+ char address[MAX_STRING_SIZE] = "";
+ char port[MAX_STRING_SIZE] = "";
+ int cipher, digest, maclength, compression;
+ node_t *from, *to;
+
+ if(sscanf(request, "%*d "MAX_STRING" "MAX_STRING" "MAX_STRING" %d %d %d %d "MAX_STRING" "MAX_STRING,
+ from_name, to_name, key, &cipher, &digest, &maclength,
+ &compression, address, port) < 7) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "ANS_KEY", c->name,
+ c->hostname);
+ return false;
+ }
+
+ if(!check_id(from_name) || !check_id(to_name)) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "ANS_KEY", c->name, c->hostname, "invalid name");
+ return false;
+ }
+
+ from = lookup_node(from_name);
+
+ if(!from) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got %s from %s (%s) origin %s which does not exist in our connection list",
+ "ANS_KEY", c->name, c->hostname, from_name);
+ return true;
+ }
+
+ to = lookup_node(to_name);
+
+ if(!to) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got %s from %s (%s) destination %s which does not exist in our connection list",
+ "ANS_KEY", c->name, c->hostname, to_name);
+ return true;
+ }
+
+ /* Forward it if necessary */
+
+ if(to != myself) {
+ if(tunnelserver)
+ return true;
+
+ if(!to->status.reachable) {
+ logger(DEBUG_ALWAYS, LOG_WARNING, "Got %s from %s (%s) destination %s which is not reachable",
+ "ANS_KEY", c->name, c->hostname, to_name);
+ return true;
+ }
+
+ if(!*address && from->address.sa.sa_family != AF_UNSPEC && to->minmtu) {
+ char *address, *port;
+ logger(DEBUG_PROTOCOL, LOG_DEBUG, "Appending reflexive UDP address to ANS_KEY from %s to %s", from->name, to->name);
+ sockaddr2str(&from->address, &address, &port);
+ send_request(to->nexthop->connection, "%s %s %s", request, address, port);
+ free(address);
+ free(port);
+ return true;
+ }
+
+ 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
+ if (!from->status.sptps) from->status.validkey = false;
+
+ if(compression < 0 || compression > 11) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses bogus compression level!", from->name, from->hostname);
+ return true;
+ }
+
+ from->outcompression = compression;
+
+ /* SPTPS or old-style key exchange? */
+
+ if(from->status.sptps) {
+ char buf[strlen(key)];
+ int len = b64decode(key, buf, strlen(key));
+ 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) {
+ logger(DEBUG_PROTOCOL, LOG_DEBUG, "Using reflexive UDP address from %s: %s port %s", from->name, address, port);
+ sockaddr_t sa = str2sockaddr(address, port);
+ update_node_udp(from, &sa);
+ }
+ }
+
+ 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(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(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)) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses bogus MAC length!", from->name, from->hostname);
+ return false;
+ }
+
+ /* Process key */
+
+ int keylen = hex2bin(key, key, sizeof key);
+
+ 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(from->outcipher && !cipher_set_key(from->outcipher, key, true))
+ return false;
+ if(from->outdigest && !digest_set_key(from->outdigest, key, keylen))
+ return false;
+
+ from->status.validkey = true;
+ from->sent_seqno = 0;
+
+ if(*address && *port) {
+ logger(DEBUG_PROTOCOL, LOG_DEBUG, "Using reflexive UDP address from %s: %s port %s", from->name, address, port);
+ sockaddr_t sa = str2sockaddr(address, port);
+ update_node_udp(from, &sa);
+ }
+
+ return true;
+#endif
}