/*
protocol_key.c -- handle the meta-protocol, key exchange
Copyright (C) 1999-2005 Ivo Timmermans,
- 2000-2008 Guus Sliepen <guus@tinc-vpn.org>
+ 2000-2009 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
#include <openssl/evp.h>
#include <openssl/err.h>
+#include <openssl/rand.h>
#include "avl_tree.h"
#include "connection.h"
bool mykeyused = false;
-bool send_key_changed(connection_t *c, const node_t *n)
+bool send_key_changed()
{
cp();
This reduces unnecessary key_changed broadcasts.
*/
- if(n == myself && !mykeyused)
+ if(!mykeyused)
return true;
- return send_request(c, "%d %lx %s", KEY_CHANGED, random(), n->name);
+ return send_request(broadcast, "%d %lx %s", KEY_CHANGED, random(), myself->name);
}
bool key_changed_h(connection_t *c)
return true;
}
-bool send_req_key(connection_t *c, const node_t *from, const node_t *to)
+bool send_req_key(node_t *to)
{
cp();
- return send_request(c, "%d %s %s", REQ_KEY, from->name, to->name);
+ return send_request(to->nexthop->connection, "%d %s %s", REQ_KEY, myself->name, to->name);
}
bool req_key_h(connection_t *c)
/* Check if this key request is for us */
if(to == myself) { /* Yes, send our own key back */
- mykeyused = true;
- from->received_seqno = 0;
- memset(from->late, 0, sizeof(from->late));
- send_ans_key(c, myself, from);
+ send_ans_key(from);
} else {
if(tunnelserver)
return false;
return true;
}
- send_req_key(to->nexthop->connection, from, to);
+ send_request(to->nexthop->connection, "%s", c->buffer);
}
return true;
}
-bool send_ans_key(connection_t *c, const node_t *from, const node_t *to)
+bool send_ans_key(node_t *to)
{
char *key;
cp();
- key = alloca(2 * from->keylength + 1);
- bin2hex(from->key, key, from->keylength);
- key[from->keylength * 2] = '\0';
-
- 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);
+ // Set key parameters
+ to->incipher = myself->incipher;
+ to->inkeylength = myself->inkeylength;
+ to->indigest = myself->indigest;
+ to->incompression = myself->incompression;
+
+ // Allocate memory for key
+ to->inkey = xrealloc(to->inkey, to->inkeylength);
+
+ // Create a new key
+ RAND_pseudo_bytes((unsigned char *)to->inkey, to->inkeylength);
+ if(to->incipher)
+ EVP_DecryptInit_ex(&to->inctx, to->incipher, NULL, (unsigned char *)to->inkey, (unsigned char *)to->inkey + to->incipher->key_len);
+
+ // Reset sequence number and late packet window
+ mykeyused = true;
+ to->received_seqno = 0;
+ memset(to->late, 0, sizeof(to->late));
+
+ // Convert to hexadecimal and send
+ key = alloca(2 * to->inkeylength + 1);
+ bin2hex(to->inkey, key, to->inkeylength);
+ key[to->inkeylength * 2] = '\0';
+
+ return send_request(to->nexthop->connection, "%d %s %s %s %d %d %d %d", ANS_KEY,
+ myself->name, to->name, key,
+ to->incipher ? to->incipher->nid : 0,
+ to->indigest ? to->indigest->type : 0, to->inmaclength,
+ to->incompression);
}
bool ans_key_h(connection_t *c)
}
/* Update our copy of the origin's packet key */
+ from->outkey = xrealloc(from->outkey, strlen(key) / 2);
- 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->outkey = xstrdup(key);
+ from->outkeylength = strlen(key) / 2;
+ hex2bin(key, from->outkey, from->outkeylength);
- from->status.validkey = true;
from->status.waitingforkey = false;
- from->sent_seqno = 0;
-
/* Check and lookup cipher and digest algorithms */
if(cipher) {
- from->cipher = EVP_get_cipherbynid(cipher);
+ from->outcipher = EVP_get_cipherbynid(cipher);
- if(!from->cipher) {
+ if(!from->outcipher) {
logger(LOG_ERR, _("Node %s (%s) uses unknown cipher!"), from->name,
from->hostname);
return false;
}
- if(from->keylength != from->cipher->key_len + from->cipher->iv_len) {
+ if(from->outkeylength != from->outcipher->key_len + from->outcipher->iv_len) {
logger(LOG_ERR, _("Node %s (%s) uses wrong keylength!"), from->name,
from->hostname);
return false;
}
} else {
- from->cipher = NULL;
+ from->outcipher = NULL;
}
- from->maclength = maclength;
+ from->outmaclength = maclength;
if(digest) {
- from->digest = EVP_get_digestbynid(digest);
+ from->outdigest = EVP_get_digestbynid(digest);
- if(!from->digest) {
+ if(!from->outdigest) {
logger(LOG_ERR, _("Node %s (%s) uses unknown digest!"), from->name,
from->hostname);
return false;
}
- if(from->maclength > from->digest->md_size || from->maclength < 0) {
+ if(from->outmaclength > from->outdigest->md_size || from->outmaclength < 0) {
logger(LOG_ERR, _("Node %s (%s) uses bogus MAC length!"),
from->name, from->hostname);
return false;
}
} else {
- from->digest = NULL;
+ from->outdigest = NULL;
}
if(compression < 0 || compression > 11) {
return false;
}
- from->compression = compression;
+ from->outcompression = compression;
- if(from->cipher)
- if(!EVP_EncryptInit_ex(&from->packet_ctx, from->cipher, NULL, (unsigned char *)from->key, (unsigned char *)from->key + from->cipher->key_len)) {
+ if(from->outcipher)
+ if(!EVP_EncryptInit_ex(&from->outctx, from->outcipher, NULL, (unsigned char *)from->outkey, (unsigned char *)from->outkey + from->outcipher->key_len)) {
logger(LOG_ERR, _("Error during initialisation of key from %s (%s): %s"),
from->name, from->hostname, ERR_error_string(ERR_get_error(), NULL));
return false;
}
+ from->status.validkey = true;
+ from->sent_seqno = 0;
+
if(from->options & OPTION_PMTU_DISCOVERY && !from->mtuprobes)
send_mtu_probe(from);
- flush_queue(from);
-
return true;
}