/*
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,
+ 2000-2009 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
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 1.2 2002/04/09 15:26:01 zarq 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 "system.h"
-#include <utils.h>
-#include <xalloc.h>
-#include <avl_tree.h>
+#include <openssl/evp.h>
+#include <openssl/err.h>
+#include <openssl/rand.h>
-#include "conf.h"
+#include "avl_tree.h"
+#include "connection.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 "protocol.h"
+#include "utils.h"
+#include "xalloc.h"
-#include "system.h"
+bool mykeyused = false;
-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;
+bool send_key_changed() {
+ /* Only send this message if some other daemon requested our key previously.
+ This reduces unnecessary key_changed broadcasts.
+ */
+
+ if(!mykeyused)
+ return true;
+
+ return send_request(broadcast, "%d %x %s", KEY_CHANGED, rand(), myself->name);
}
-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;
+bool key_changed_h(connection_t *c) {
+ char name[MAX_STRING_SIZE];
+ node_t *n;
+
+ if(sscanf(c->buffer, "%*d %*x " MAX_STRING, name) != 1) {
+ logger(LOG_ERR, "Got bad %s from %s (%s)", "KEY_CHANGED",
+ c->name, c->hostname);
+ return false;
+ }
+
+ if(seen_request(c->buffer))
+ return true;
+
+ n = lookup_node(name);
+
+ if(!n) {
+ logger(LOG_ERR, "Got %s from %s (%s) origin %s which does not exist",
+ "KEY_CHANGED", c->name, c->hostname, name);
+ return false;
+ }
+
+ n->status.validkey = false;
+ n->status.waitingforkey = false;
+
+ /* Tell the others */
+
+ if(!tunnelserver)
+ forward_request(c);
+
+ return true;
}
-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);
+bool send_req_key(node_t *to) {
+ return send_request(to->nexthop->connection, "%d %s %s", REQ_KEY, myself->name, to->name);
}
-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 req_key_h(connection_t *c) {
+ char from_name[MAX_STRING_SIZE];
+ char to_name[MAX_STRING_SIZE];
+ node_t *from, *to;
+
+ if(sscanf(c->buffer, "%*d " MAX_STRING " " MAX_STRING, from_name, to_name) != 2) {
+ logger(LOG_ERR, "Got bad %s from %s (%s)", "REQ_KEY", c->name,
+ c->hostname);
+ return false;
+ }
+
+ from = lookup_node(from_name);
+
+ if(!from) {
+ logger(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 false;
+ }
+
+ to = lookup_node(to_name);
+
+ if(!to) {
+ logger(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 false;
+ }
+
+ /* Check if this key request is for us */
+
+ if(to == myself) { /* Yes, send our own key back */
+ send_ans_key(from);
+ } else {
+ if(tunnelserver)
+ return false;
-cp
- return 0;
+ if(!to->status.reachable) {
+ logger(LOG_WARNING, "Got %s from %s (%s) destination %s which is not reachable",
+ "REQ_KEY", c->name, c->hostname, to_name);
+ return true;
+ }
+
+ send_request(to->nexthop->connection, "%s", c->buffer);
+ }
+
+ return true;
}
-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);
+bool send_ans_key(node_t *to) {
+ char *key;
+
+ // Set key parameters
+ to->incipher = myself->incipher;
+ to->inkeylength = myself->inkeylength;
+ to->indigest = myself->indigest;
+ to->inmaclength = myself->inmaclength;
+ 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);
}
-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 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;
+
+ 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) {
+ logger(LOG_ERR, "Got bad %s from %s (%s)", "ANS_KEY", c->name,
+ c->hostname);
+ return false;
+ }
+
+ from = lookup_node(from_name);
+
+ if(!from) {
+ logger(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 false;
+ }
+
+ to = lookup_node(to_name);
+
+ if(!to) {
+ logger(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 false;
+ }
+
+ /* Forward it if necessary */
+
+ if(to != myself) {
+ if(tunnelserver)
+ return false;
+
+ if(!to->status.reachable) {
+ logger(LOG_WARNING, "Got %s from %s (%s) destination %s which is not reachable",
+ "ANS_KEY", c->name, c->hostname, to_name);
+ return true;
+ }
+
+ return send_request(to->nexthop->connection, "%s", c->buffer);
+ }
+
+ /* Update our copy of the origin's packet key */
+ from->outkey = xrealloc(from->outkey, strlen(key) / 2);
+
+ from->outkey = xstrdup(key);
+ from->outkeylength = strlen(key) / 2;
+ hex2bin(key, from->outkey, from->outkeylength);
+
+ from->status.waitingforkey = false;
+ /* Check and lookup cipher and digest algorithms */
+
+ if(cipher) {
+ from->outcipher = EVP_get_cipherbynid(cipher);
+
+ if(!from->outcipher) {
+ logger(LOG_ERR, "Node %s (%s) uses unknown cipher!", from->name,
+ from->hostname);
+ return false;
+ }
+
+ 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->outcipher = NULL;
}
- 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;
+
+ from->outmaclength = maclength;
+
+ if(digest) {
+ from->outdigest = EVP_get_digestbynid(digest);
+
+ if(!from->outdigest) {
+ logger(LOG_ERR, "Node %s (%s) uses unknown digest!", from->name,
+ from->hostname);
+ return false;
+ }
+
+ 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->outdigest = NULL;
}
- 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;
+
+ if(compression < 0 || compression > 11) {
+ logger(LOG_ERR, "Node %s (%s) uses bogus compression level!", from->name, from->hostname);
+ return false;
}
- }
- else
- {
- from->digest = NULL;
- }
-
- from->compression = compression;
-
- flush_queue(from);
-cp
- return 0;
+
+ from->outcompression = compression;
+
+ 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);
+
+ return true;
}