/*
protocol_key.c -- handle the meta-protocol, key exchange
- Copyright (C) 1999-2003 Ivo Timmermans <ivo@o2w.nl>,
- 2000-2003 Guus Sliepen <guus@sliepen.eu.org>
+ Copyright (C) 1999-2005 Ivo Timmermans,
+ 2000-2016 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 1.1.4.18 2003/07/12 17:41:47 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 <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 "logger.h"
+#include "protocol.h"
+#include "utils.h"
+#include "xalloc.h"
-#include "system.h"
+static bool mykeyused = false;
-int mykeyused = 0;
+void send_key_changed(void) {
+ avl_node_t *node;
+ connection_t *c;
-int send_key_changed(connection_t *c, node_t *n)
-{
- cp();
+ send_request(everyone, "%d %x %s", KEY_CHANGED, rand(), myself->name);
- /* Only send this message if some other daemon requested our key previously.
- This reduces unnecessary key_changed broadcasts.
- */
+ /* Immediately send new keys to directly connected nodes to keep UDP mappings alive */
- if(n == myself && !mykeyused)
- return 0;
+ for(node = connection_tree->head; node; node = node->next) {
+ c = node->data;
- return send_request(c, "%d %lx %s", KEY_CHANGED, random(), n->name);
+ if(c->status.active && c->node && c->node->status.reachable) {
+ send_ans_key(c->node);
+ }
+ }
}
-int key_changed_h(connection_t *c)
-{
+bool key_changed_h(connection_t *c) {
char name[MAX_STRING_SIZE];
node_t *n;
- cp();
-
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 -1;
+ logger(LOG_ERR, "Got bad %s from %s (%s)", "KEY_CHANGED",
+ c->name, c->hostname);
+ return false;
}
- if(seen_request(c->buffer))
- return 0;
+ if(!check_id(name)) {
+ logger(LOG_ERR, "Got bad %s from %s (%s): %s", "KEY_CHANGED", c->name, c->hostname, "invalid name");
+ 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 -1;
+ logger(LOG_ERR, "Got %s from %s (%s) origin %s which does not exist",
+ "KEY_CHANGED", c->name, c->hostname, name);
+ return true;
}
- n->status.validkey = 0;
- n->status.waitingforkey = 0;
+ n->status.validkey = false;
+ n->last_req_key = 0;
/* Tell the others */
- forward_request(c);
+ if(!tunnelserver) {
+ forward_request(c);
+ }
- return 0;
+ 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)
-{
+bool 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) {
- logger(LOG_ERR, _("Got bad %s from %s (%s)"), "REQ_KEY", c->name,
- c->hostname);
- return -1;
+ logger(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(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(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;
+ 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 true;
}
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 -1;
+ 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 true;
}
/* Check if this key request is for us */
- if(to == myself) { /* Yes, send our own key back */
- mykeyused = 1;
- from->received_seqno = 0;
- memset(from->late, 0, sizeof(from->late));
- send_ans_key(c, myself, from);
+ if(to == myself) { /* Yes, send our own key back */
+ if(!send_ans_key(from)) {
+ return false;
+ }
} else {
- send_req_key(to->nexthop->connection, from, to);
+ if(tunnelserver) {
+ return true;
+ }
+
+ 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 0;
+ return true;
}
-int send_ans_key(connection_t *c, node_t *from, node_t *to)
-{
- char key[MAX_STRING_SIZE];
+bool send_ans_key(node_t *to) {
+ // 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
+ if(1 != RAND_bytes((unsigned char *)to->inkey, to->inkeylength)) {
+ int err = ERR_get_error();
+ logger(LOG_ERR, "Failed to generate random for key (%s)", ERR_error_string(err, NULL));
+ return false; // Do not send insecure keys, let connection attempt fail.
+ }
+
+ if(to->incipher) {
+ EVP_DecryptInit_ex(to->inctx, to->incipher, NULL, (unsigned char *)to->inkey, (unsigned char *)to->inkey + EVP_CIPHER_key_length(to->incipher));
+ }
- cp();
+ // Reset sequence number and late packet window
+ mykeyused = true;
+ to->received_seqno = 0;
- bin2hex(from->key, key, from->keylength);
- key[from->keylength * 2] = '\0';
+ if(replaywin) {
+ memset(to->late, 0, replaywin);
+ }
- 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);
+ // Convert to hexadecimal and send
+ char key[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 ? EVP_CIPHER_nid(to->incipher) : 0,
+ to->indigest ? EVP_MD_type(to->indigest) : 0, to->inmaclength,
+ to->incompression);
}
-int ans_key_h(connection_t *c)
-{
+bool ans_key_h(connection_t *c) {
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;
- cp();
+ if(sscanf(c->buffer, "%*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(LOG_ERR, "Got bad %s from %s (%s)", "ANS_KEY", c->name,
+ c->hostname);
+ return false;
+ }
- 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 -1;
+ if(!check_id(from_name) || !check_id(to_name)) {
+ logger(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(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;
+ 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 true;
}
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 -1;
+ 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 true;
}
/* Forward it if necessary */
if(to != myself) {
+ if(tunnelserver) {
+ return true;
+ }
+
+ 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;
+ }
+
+ if(!*address && from->address.sa.sa_family != AF_UNSPEC && to->minmtu) {
+ char *address, *port;
+ ifdebug(PROTOCOL) logger(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", c->buffer, address, port);
+ free(address);
+ free(port);
+ return true;
+ }
+
return send_request(to->nexthop->connection, "%s", c->buffer);
}
- /* Update our copy of the origin's packet key */
-
- if(from->key)
- free(from->key);
+ /* Don't use key material until every check has passed. */
+ from->status.validkey = false;
- from->key = xstrdup(key);
- from->keylength = strlen(key) / 2;
- hex2bin(from->key, from->key, from->keylength);
- from->key[from->keylength] = '\0';
+ /* Update our copy of the origin's packet key */
+ from->outkey = xrealloc(from->outkey, strlen(key) / 2);
+ from->outkeylength = strlen(key) / 2;
- from->status.validkey = 1;
- from->status.waitingforkey = 0;
- from->sent_seqno = 0;
+ if(!hex2bin(key, from->outkey, from->outkeylength)) {
+ logger(LOG_ERR, "Got bad %s from %s(%s): %s", "ANS_KEY", from->name, from->hostname, "invalid key");
+ return true;
+ }
/* Check and lookup cipher and digest algorithms */
if(cipher) {
- from->cipher = EVP_get_cipherbynid(cipher);
+ from->outcipher = EVP_get_cipherbynid(cipher);
- if(!from->cipher) {
- logger(LOG_ERR, _("Node %s (%s) uses unknown cipher!"), from->name,
- from->hostname);
- return -1;
+ if(!from->outcipher) {
+ logger(LOG_ERR, "Node %s (%s) uses unknown cipher!", from->name,
+ from->hostname);
+ return true;
}
- if(from->keylength != from->cipher->key_len + from->cipher->iv_len) {
- logger(LOG_ERR, _("Node %s (%s) uses wrong keylength!"), from->name,
- from->hostname);
- return -1;
+ if(from->outkeylength != EVP_CIPHER_key_length(from->outcipher) + EVP_CIPHER_iv_length(from->outcipher)) {
+ logger(LOG_ERR, "Node %s (%s) uses wrong keylength!", from->name,
+ from->hostname);
+ return true;
}
} else {
- from->cipher = NULL;
+ if(from->outkeylength != 1) {
+ logger(LOG_ERR, "Node %s (%s) uses wrong keylength!", from->name, from->hostname);
+ return true;
+ }
+
+ 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) {
- logger(LOG_ERR, _("Node %s (%s) uses unknown digest!"), from->name,
- from->hostname);
- return -1;
+ if(!from->outdigest) {
+ logger(LOG_ERR, "Node %s (%s) uses unknown digest!", from->name,
+ from->hostname);
+ return true;
}
- if(from->maclength > from->digest->md_size || from->maclength < 0) {
- logger(LOG_ERR, _("Node %s (%s) uses bogus MAC length!"),
- from->name, from->hostname);
- return -1;
+ if(from->outmaclength > EVP_MD_size(from->outdigest) || from->outmaclength < 0) {
+ logger(LOG_ERR, "Node %s (%s) uses bogus MAC length!",
+ from->name, from->hostname);
+ return true;
}
} else {
- from->digest = NULL;
+ from->outdigest = NULL;
}
if(compression < 0 || compression > 11) {
- logger(LOG_ERR, _("Node %s (%s) uses bogus compression level!"), from->name, from->hostname);
- return -1;
+ logger(LOG_ERR, "Node %s (%s) uses bogus compression level!", from->name, from->hostname);
+ return true;
}
-
- from->compression = compression;
- EVP_EncryptInit_ex(&from->packet_ctx, from->cipher, NULL, from->key, from->key + from->cipher->key_len);
+ from->outcompression = compression;
- flush_queue(from);
+ if(from->outcipher)
+ if(!EVP_EncryptInit_ex(from->outctx, from->outcipher, NULL, (unsigned char *)from->outkey, (unsigned char *)from->outkey + EVP_CIPHER_key_length(from->outcipher))) {
+ logger(LOG_ERR, "Error during initialisation of key from %s (%s): %s",
+ from->name, from->hostname, ERR_error_string(ERR_get_error(), NULL));
+ return true;
+ }
+
+ from->status.validkey = true;
+ from->sent_seqno = 0;
+
+ if(*address && *port) {
+ ifdebug(PROTOCOL) logger(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);
+ }
+
+ if(from->options & OPTION_PMTU_DISCOVERY && !from->mtuevent) {
+ send_mtu_probe(from);
+ }
- return 0;
+ return true;
}
projects / oweals / tinc.git / blobdiff