#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 = myself->connection->protocol_minor;
+ if(c->config_tree && !read_ecdsa_public_key(c))
+ minor = 1;
+
+ 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 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;
}
c->name);
return false;
}
- }
- if(!read_rsa_public_key(c)) {
- return false;
+ if(c->protocol_minor >= 2)
+ if(!read_ecdsa_public_key(c))
+ return false;
+ } else {
+ if(!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];
+ char sig[siglen];
+
+ // 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, sig))
+ return false;
+
+ char out[MAX_STRING_SIZE];
+
+ bin2hex(key, out, ECDH_SIZE);
+ bin2hex(sig, out + ECDH_SIZE * 2, siglen);
+ out[(ECDH_SIZE + siglen) * 2] = 0;
+
+ bool result = send_request(c, "%d %s", METAKEY, out);
}
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);
return result;
}
+static bool metakey_ec_h(connection_t *c, const char *request) {
+ size_t siglen = ecdsa_size(&c->ecdsa);
+ char in[MAX_STRING_SIZE];
+ char key[MAX_STRING_SIZE];
+ char sig[siglen];
+
+ logger(LOG_DEBUG, "Got ECDH metakey from %s", c->name);
+
+ if(sscanf(request, "%*d " MAX_STRING, in) != 1) {
+ logger(LOG_ERR, "Got bad %s from %s (%s)", "METAKEY", c->name, c->hostname);
+ return false;
+ }
+
+ if(strlen(in) != (ECDH_SIZE + siglen) * 2) {
+ logger(LOG_ERR, "Possible intruder %s (%s): %s %d != %d", c->name, c->hostname, "wrong keylength", strlen(in) / 2, (ECDH_SIZE + siglen));
+ return false;
+ }
+
+ hex2bin(in, key, ECDH_SIZE);
+ hex2bin(in + ECDH_SIZE * 2, sig, siglen);
+
+ if(!ecdsa_verify(&c->ecdsa, key, ECDH_SIZE, sig)) {
+ logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "invalid ECDSA signature");
+ return false;
+ }
+
+ char shared[ECDH_SHARED_SIZE * 2 + 1];
+
+ 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);
+
+ bin2hex(shared, shared, ECDH_SHARED_SIZE);
+ shared[ECDH_SHARED_SIZE * 2] = 0;
+ logger(LOG_DEBUG, "Shared secret is %s", shared);
+
+ cipher_set_key(&c->incipher, mykey, true);
+ digest_set_key(&c->indigest, mykey + mykeylen, mykeylen);
+
+ cipher_set_key(&c->outcipher, hiskey, false);
+ 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);
}
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)
bool challenge_h(connection_t *c, char *request) {
char buffer[MAX_STRING_SIZE];
- size_t len = rsa_size(&myself->connection->rsa);
+ size_t len = c->protocol_minor >= 2 ? ECDH_SIZE : rsa_size(&myself->connection->rsa);
size_t digestlen = digest_length(&c->indigest);
char digest[digestlen];
/* Verify the hash */
- if(!digest_verify(&c->outdigest, c->hischallenge, rsa_size(&c->rsa), hishash)) {
+ 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. */
}
}
+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_connection_config(c, "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;
int weight, mtu;
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)) {
c->options &= ~OPTION_CLAMP_MSS;
}
+ if(c->protocol_minor > 0)
+ c->node->status.ecdh = true;
+
/* Activate this connection */
c->allow_request = ALL;