/*
protocol_auth.c -- handle the meta-protocol, authentication
Copyright (C) 1999-2005 Ivo Timmermans,
- 2000-2009 Guus Sliepen <guus@tinc-vpn.org>
+ 2000-2010 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 "splay_tree.h"
#include "conf.h"
#include "connection.h"
+#include "control.h"
+#include "control_common.h"
+#include "cipher.h"
#include "crypto.h"
+#include "digest.h"
#include "edge.h"
#include "graph.h"
#include "logger.h"
#include "net.h"
#include "netutl.h"
#include "node.h"
+#include "prf.h"
#include "protocol.h"
#include "rsa.h"
#include "utils.h"
bool send_id(connection_t *c) {
gettimeofday(&c->start, NULL);
- return send_request(c, "%d %s %d", ID, myself->connection->name,
- myself->connection->protocol_version);
+ int minor = 0;
+
+ if(experimental) {
+ if(c->config_tree && !read_ecdsa_public_key(c))
+ minor = 1;
+ else
+ minor = myself->connection->protocol_minor;
+ }
+
+ return send_request(c, "%d %s %d.%d", ID, myself->connection->name, myself->connection->protocol_major, minor);
}
bool id_h(connection_t *c, char *request) {
char name[MAX_STRING_SIZE];
- if(sscanf(request, "%*d " MAX_STRING " %d", name, &c->protocol_version) != 2) {
+ if(sscanf(request, "%*d " MAX_STRING " %d.%d", name, &c->protocol_major, &c->protocol_minor) < 2) {
logger(LOG_ERR, "Got bad %s from %s (%s)", "ID", c->name,
c->hostname);
return false;
}
+ /* Check if this is a control connection */
+
+ if(name[0] == '^' && !strcmp(name + 1, controlcookie)) {
+ c->status.control = true;
+ c->allow_request = CONTROL;
+ c->last_ping_time = time(NULL) + 3600;
+ return send_request(c, "%d %d %d", ACK, TINC_CTL_VERSION_CURRENT, getpid());
+ }
+
/* Check if identity is a valid name */
if(!check_id(name)) {
/* Check if version matches */
- if(c->protocol_version != myself->connection->protocol_version) {
- logger(LOG_ERR, "Peer %s (%s) uses incompatible version %d",
- c->name, c->hostname, c->protocol_version);
+ if(c->protocol_major != myself->connection->protocol_major) {
+ logger(LOG_ERR, "Peer %s (%s) uses incompatible version %d.%d",
+ c->name, c->hostname, c->protocol_major, c->protocol_minor);
return false;
}
return send_ack(c);
}
+ if(!experimental)
+ c->protocol_minor = 0;
+
if(!c->config_tree) {
init_configuration(&c->config_tree);
c->name);
return false;
}
- }
- if(!read_rsa_public_key(c)) {
- return false;
+ if(experimental && c->protocol_minor >= 2)
+ if(!read_ecdsa_public_key(c))
+ return false;
+ } else {
+ if(c->protocol_minor && !ecdsa_active(&c->ecdsa))
+ c->protocol_minor = 1;
}
c->allow_request = METAKEY;
- return send_metakey(c);
+ if(c->protocol_minor >= 2)
+ return send_metakey_ec(c);
+ else
+ return send_metakey(c);
+}
+
+bool send_metakey_ec(connection_t *c) {
+ logger(LOG_DEBUG, "Sending ECDH metakey to %s", c->name);
+
+ size_t siglen = ecdsa_size(&myself->connection->ecdsa);
+
+ char key[(ECDH_SIZE + siglen) * 2 + 1];
+
+ // TODO: include nonce? Use relevant parts of SSH or TLS protocol
+
+ if(!ecdh_generate_public(&c->ecdh, key))
+ return false;
+
+ if(!ecdsa_sign(&myself->connection->ecdsa, key, ECDH_SIZE, key + ECDH_SIZE))
+ return false;
+
+ b64encode(key, key, ECDH_SIZE + siglen);
+
+ return send_request(c, "%d %s", METAKEY, key);
}
bool send_metakey(connection_t *c) {
- size_t len = rsa_size(&c->rsa);
- char key[len];
- char enckey[len];
- char hexkey[2 * len + 1];
+ if(!read_rsa_public_key(c))
+ return false;
if(!cipher_open_blowfish_ofb(&c->outcipher))
return false;
if(!digest_open_sha1(&c->outdigest, -1))
return false;
+ size_t len = rsa_size(&c->rsa);
+ char key[len];
+ char enckey[len];
+ char hexkey[2 * len + 1];
+
/* Create a random key */
randomize(key, len);
ifdebug(SCARY_THINGS) {
bin2hex(key, hexkey, len);
- hexkey[len * 2] = '\0';
logger(LOG_DEBUG, "Generated random meta key (unencrypted): %s", hexkey);
}
/* Convert the encrypted random data to a hexadecimal formatted string */
bin2hex(enckey, hexkey, len);
- hexkey[len * 2] = '\0';
/* Send the meta key */
return result;
}
+static bool metakey_ec_h(connection_t *c, const char *request) {
+ size_t siglen = ecdsa_size(&c->ecdsa);
+ char key[MAX_STRING_SIZE];
+
+ logger(LOG_DEBUG, "Got ECDH metakey from %s", c->name);
+
+ if(sscanf(request, "%*d " MAX_STRING, key) != 1) {
+ logger(LOG_ERR, "Got bad %s from %s (%s)", "METAKEY", c->name, c->hostname);
+ return false;
+ }
+
+ int inlen = b64decode(key, key, sizeof key);
+
+ if(inlen != (ECDH_SIZE + siglen)) {
+ logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "wrong keylength");
+ return false;
+ }
+
+ if(!ecdsa_verify(&c->ecdsa, key, ECDH_SIZE, key + ECDH_SIZE)) {
+ logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "invalid ECDSA signature");
+ return false;
+ }
+
+ char shared[ECDH_SHARED_SIZE];
+
+ if(!ecdh_compute_shared(&c->ecdh, key, shared))
+ return false;
+
+ /* Update our crypto end */
+
+ if(!cipher_open_by_name(&c->incipher, "aes-256-ofb"))
+ return false;
+ if(!digest_open_by_name(&c->indigest, "sha512", -1))
+ return false;
+ if(!cipher_open_by_name(&c->outcipher, "aes-256-ofb"))
+ return false;
+ if(!digest_open_by_name(&c->outdigest, "sha512", -1))
+ return false;
+
+ size_t mykeylen = cipher_keylength(&c->incipher);
+ size_t hiskeylen = cipher_keylength(&c->outcipher);
+
+ char *mykey;
+ char *hiskey;
+ char *seed;
+
+ if(strcmp(myself->name, c->name) < 0) {
+ mykey = key;
+ hiskey = key + mykeylen * 2;
+ xasprintf(&seed, "tinc TCP key expansion %s %s", myself->name, c->name);
+ } else {
+ mykey = key + hiskeylen * 2;
+ hiskey = key;
+ xasprintf(&seed, "tinc TCP key expansion %s %s", c->name, myself->name);
+ }
+
+ if(!prf(shared, ECDH_SHARED_SIZE, seed, strlen(seed), key, hiskeylen * 2 + mykeylen * 2))
+ return false;
+
+ free(seed);
+
+ cipher_set_key(&c->incipher, mykey, false);
+ digest_set_key(&c->indigest, mykey + mykeylen, mykeylen);
+
+ cipher_set_key(&c->outcipher, hiskey, true);
+ digest_set_key(&c->outdigest, hiskey + hiskeylen, hiskeylen);
+
+ c->status.decryptin = true;
+ c->status.encryptout = true;
+ c->allow_request = CHALLENGE;
+
+ return send_challenge(c);
+}
+
bool metakey_h(connection_t *c, char *request) {
+ if(c->protocol_minor >= 2)
+ return metakey_ec_h(c, request);
+
char hexkey[MAX_STRING_SIZE];
int cipher, digest, maclength, compression;
size_t len = rsa_size(&myself->connection->rsa);
return false;
}
+ /* Convert the challenge from hexadecimal back to binary */
+
+ int inlen = hex2bin(hexkey, enckey, sizeof enckey);
+
/* Check if the length of the meta key is all right */
- if(strlen(hexkey) != len * 2) {
+ if(inlen != len) {
logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "wrong keylength");
return false;
}
- /* Convert the challenge from hexadecimal back to binary */
-
- hex2bin(hexkey, enckey, len);
-
/* Decrypt the meta key */
if(!rsa_private_decrypt(&myself->connection->rsa, enckey, len, key)) {
ifdebug(SCARY_THINGS) {
bin2hex(key, hexkey, len);
- hexkey[len * 2] = '\0';
logger(LOG_DEBUG, "Received random meta key (unencrypted): %s", hexkey);
}
}
bool send_challenge(connection_t *c) {
- size_t len = rsa_size(&c->rsa);
+ size_t len = c->protocol_minor >= 2 ? ECDH_SIZE : rsa_size(&c->rsa);
char buffer[len * 2 + 1];
if(!c->hischallenge)
/* Convert to hex */
bin2hex(c->hischallenge, buffer, len);
- buffer[len * 2] = '\0';
/* Send the challenge */
bool challenge_h(connection_t *c, char *request) {
char buffer[MAX_STRING_SIZE];
- size_t len = rsa_size(&myself->connection->rsa);
- size_t digestlen = digest_length(&c->outdigest);
+ size_t len = c->protocol_minor >= 2 ? ECDH_SIZE : rsa_size(&myself->connection->rsa);
+ size_t digestlen = digest_length(&c->indigest);
char digest[digestlen];
if(sscanf(request, "%*d " MAX_STRING, buffer) != 1) {
return false;
}
+ /* Convert the challenge from hexadecimal back to binary */
+
+ int inlen = hex2bin(buffer, buffer, sizeof buffer);
+
/* Check if the length of the challenge is all right */
- if(strlen(buffer) != len * 2) {
+ if(inlen != len) {
logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "wrong challenge length");
return false;
}
- /* Convert the challenge from hexadecimal back to binary */
-
- hex2bin(buffer, buffer, len);
-
c->allow_request = CHAL_REPLY;
/* Calculate the hash from the challenge we received */
/* Convert the hash to a hexadecimal formatted string */
bin2hex(digest, buffer, digestlen);
- buffer[digestlen * 2] = '\0';
/* Send the reply */
return false;
}
+ /* Convert the hash to binary format */
+
+ int inlen = hex2bin(hishash, hishash, sizeof hishash);
+
/* Check if the length of the hash is all right */
- if(strlen(hishash) != digest_length(&c->outdigest) * 2) {
- logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, _("wrong challenge reply length"));
+ if(inlen != digest_length(&c->outdigest)) {
+ logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "wrong challenge reply length");
return false;
}
- /* Convert the hash to binary format */
-
- hex2bin(hishash, hishash, digest_length(&c->outdigest));
/* Verify the hash */
- if(!digest_verify(&c->outdigest, c->hischallenge, rsa_size(&c->rsa), hishash)) {
- logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, _("wrong challenge reply"));
+ if(!digest_verify(&c->outdigest, c->hischallenge, c->protocol_minor >= 2 ? ECDH_SIZE : rsa_size(&c->rsa), hishash)) {
+ logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "wrong challenge reply");
return false;
}
return send_ack(c);
}
+static bool send_upgrade(connection_t *c) {
+ /* Special case when protocol_minor is 1: the other end is ECDSA capable,
+ * but doesn't know our key yet. So send it now. */
+
+ char *pubkey = ecdsa_get_base64_public_key(&myself->connection->ecdsa);
+
+ if(!pubkey)
+ return false;
+
+ bool result = send_request(c, "%d %s", ACK, pubkey);
+ free(pubkey);
+ return result;
+}
+
bool send_ack(connection_t *c) {
+ if(c->protocol_minor == 1)
+ return send_upgrade(c);
+
/* ACK message contains rest of the information the other end needs
to create node_t and edge_t structures. */
if(myself->options & OPTION_PMTU_DISCOVERY)
c->options |= OPTION_PMTU_DISCOVERY;
+ choice = myself->options & OPTION_CLAMP_MSS;
+ get_config_bool(lookup_config(c->config_tree, "ClampMSS"), &choice);
+ if(choice)
+ c->options |= OPTION_CLAMP_MSS;
+
get_config_int(lookup_config(c->config_tree, "Weight"), &c->estimated_weight);
- return send_request(c, "%d %s %d %lx", ACK, myport, c->estimated_weight, c->options);
+ return send_request(c, "%d %s %d %x", ACK, myport, c->estimated_weight, c->options);
}
static void send_everything(connection_t *c) {
}
}
+static bool upgrade_h(connection_t *c, char *request) {
+ char pubkey[MAX_STRING_SIZE];
+
+ if(sscanf(request, "%*d " MAX_STRING, pubkey) != 1) {
+ logger(LOG_ERR, "Got bad %s from %s (%s)", "ACK", c->name, c->hostname);
+ return false;
+ }
+
+ if(ecdsa_active(&c->ecdsa) || read_ecdsa_public_key(c)) {
+ logger(LOG_INFO, "Already have ECDSA public key from %s (%s), not upgrading.", c->name, c->hostname);
+ return false;
+ }
+
+ logger(LOG_INFO, "Got ECDSA public key from %s (%s), upgrading!", c->name, c->hostname);
+ append_config_file(c->name, "ECDSAPublicKey", pubkey);
+ c->allow_request = TERMREQ;
+ return send_termreq(c);
+}
+
bool ack_h(connection_t *c, char *request) {
+ if(c->protocol_minor == 1)
+ return upgrade_h(c, request);
+
char hisport[MAX_STRING_SIZE];
- char *hisaddress, *dummy;
+ char *hisaddress;
int weight, mtu;
- long int options;
+ uint32_t options;
node_t *n;
+ bool choice;
- if(sscanf(request, "%*d " MAX_STRING " %d %lx", hisport, &weight, &options) != 3) {
+ if(sscanf(request, "%*d " MAX_STRING " %d %x", hisport, &weight, &options) != 3) {
logger(LOG_ERR, "Got bad %s from %s (%s)", "ACK", c->name,
c->hostname);
return false;
if(get_config_int(lookup_config(c->config_tree, "PMTU"), &mtu) && mtu < n->mtu)
n->mtu = mtu;
- if(get_config_int(lookup_config(myself->connection->config_tree, "PMTU"), &mtu) && mtu < n->mtu)
+ if(get_config_int(lookup_config(config_tree, "PMTU"), &mtu) && mtu < n->mtu)
n->mtu = mtu;
+ if(get_config_bool(lookup_config(c->config_tree, "ClampMSS"), &choice)) {
+ if(choice)
+ c->options |= OPTION_CLAMP_MSS;
+ else
+ c->options &= ~OPTION_CLAMP_MSS;
+ }
+
+ if(c->protocol_minor > 0)
+ c->node->status.ecdh = true;
+
/* Activate this connection */
c->allow_request = ALL;
c->edge = new_edge();
c->edge->from = myself;
c->edge->to = n;
- sockaddr2str(&c->address, &hisaddress, &dummy);
+ sockaddr2str(&c->address, &hisaddress, NULL);
c->edge->address = str2sockaddr(hisaddress, hisport);
free(hisaddress);
- free(dummy);
c->edge->weight = (weight + c->estimated_weight) / 2;
c->edge->connection = c;
c->edge->options = c->options;
if(tunnelserver)
send_add_edge(c, c->edge);
else
- send_add_edge(broadcast, c->edge);
+ send_add_edge(everyone, c->edge);
/* Run MST and SSSP algorithms */
projects / tinc / blobdiff