vpn_packet_t *outpkt = pkt[0];
size_t outlen;
+ if(experimental && OPTION_VERSION(n->options) >= 2) {
+ sptps_receive_data(&n->sptps, (char *)inpkt->data - 4, inpkt->len);
+ return;
+ }
+
if(!cipher_active(&n->incipher)) {
logger(DEBUG_TRAFFIC, LOG_DEBUG, "Got packet from %s (%s) but he hasn't got our key yet",
n->name, n->hostname);
return;
}
+ if(experimental && OPTION_VERSION(n->options) >= 2) {
+ uint8_t type = 0;
+ if(!(inpkt->data[12] | inpkt->data[13]))
+ type = PKT_PROBE;
+ sptps_send_record(&n->sptps, type, (char *)inpkt->data, inpkt->len);
+ return;
+ }
+
/* Compress the packet */
if(n->outcompression) {
origpkt->len = origlen;
}
+bool send_sptps_data(void *handle, uint8_t type, const char *data, size_t len) {
+ node_t *to = handle;
+
+ if(type >= SPTPS_HANDSHAKE) {
+ char buf[len * 4 / 3 + 5];
+ b64encode(data, buf, len);
+ if(!to->status.validkey)
+ return send_request(to->nexthop->connection, "%d %s %s %s -1 -1 -1 -1", ANS_KEY, myself->name, to->name, buf);
+ else
+ return send_request(to->nexthop->connection, "%d %s %s %d %s", REQ_KEY, myself->name, to->name, REQ_SPTPS, buf);
+ }
+
+ /* Send the packet */
+
+ struct sockaddr *sa;
+ socklen_t sl;
+ int sock;
+
+ sa = &(to->address.sa);
+ sl = SALEN(to->address.sa);
+ sock = to->sock;
+
+ if(sendto(listen_socket[sock].udp, data, len, 0, sa, sl) < 0 && !sockwouldblock(sockerrno)) {
+ if(sockmsgsize(sockerrno)) {
+ if(to->maxmtu >= len)
+ to->maxmtu = len - 1;
+ if(to->mtu >= len)
+ to->mtu = len - 1;
+ } else {
+ logger(DEBUG_TRAFFIC, LOG_WARNING, "Error sending UDP SPTPS packet to %s (%s): %s", to->name, to->hostname, sockstrerror(sockerrno));
+ return false;
+ }
+ }
+
+ return true;
+}
+
+bool receive_sptps_record(void *handle, uint8_t type, const char *data, uint16_t len) {
+ node_t *from = handle;
+
+ if(type == SPTPS_HANDSHAKE) {
+ from->status.validkey = true;
+ logger(DEBUG_META, LOG_INFO, "SPTPS key exchange with %s (%s) succesful", from->name, from->hostname);
+ return true;
+ }
+
+ if(len > MTU) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Packet from %s (%s) larger than maximum supported size (%d > %d)", from->name, from->hostname, len, MTU);
+ return false;
+ }
+
+ vpn_packet_t inpkt;
+ inpkt.len = len;
+ memcpy(inpkt.data, data, len);
+
+ if(type == PKT_PROBE) {
+ mtu_probe_h(from, &inpkt, len);
+ return true;
+
+ }
+ if(type != 0) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Unexpected SPTPS record type %d len %d from %s (%s)", type, len, from->name, from->hostname);
+ return false;
+ }
+
+ receive_packet(from, &inpkt);
+ return true;
+}
+
/*
send a packet to the given vpn ip.
*/
#include "cipher.h"
#include "connection.h"
#include "crypto.h"
-#include "ecdh.h"
#include "logger.h"
#include "net.h"
#include "netutl.h"
#include "node.h"
#include "prf.h"
#include "protocol.h"
+#include "sptps.h"
#include "utils.h"
#include "xalloc.h"
for(node = connection_tree->head; node; node = node->next) {
c = node->data;
- if(c->status.active && c->node && c->node->status.reachable)
- send_ans_key(c->node);
+ if(c->status.active && c->node && c->node->status.reachable) {
+ if(!experimental || OPTION_VERSION(c->node->options) < 2)
+ send_ans_key(c->node);
+ }
+ }
+
+ /* Force key exchange for connections using SPTPS */
+
+ if(experimental) {
+ for(node = node_tree->head; node; node = node->next) {
+ node_t *n = node->data;
+ if(n->status.reachable && n->status.validkey && OPTION_VERSION(n->options) >= 2)
+ sptps_force_kex(&n->sptps);
+ }
}
}
return true;
}
- n->status.validkey = false;
- n->last_req_key = 0;
+ if(OPTION_VERSION(n->options) < 2) {
+ n->status.validkey = false;
+ n->last_req_key = 0;
+ }
/* Tell the others */
return true;
}
+static bool send_initial_sptps_data(void *handle, uint8_t type, const char *data, size_t len) {
+ node_t *to = handle;
+ to->sptps.send_data = send_sptps_data;
+ char buf[len * 4 / 3 + 5];
+ b64encode(data, buf, len);
+ return send_request(to->nexthop->connection, "%d %s %s %d %s", REQ_KEY, myself->name, to->name, REQ_KEY, buf);
+}
+
bool send_req_key(node_t *to) {
if(experimental && OPTION_VERSION(to->options) >= 2) {
- if(!node_read_ecdsa_public_key(to))
+ if(!node_read_ecdsa_public_key(to)) {
+ logger(DEBUG_ALWAYS, LOG_DEBUG, "No ECDSA key known for %s (%s)", to->name, to->hostname);
send_request(to->nexthop->connection, "%d %s %s %d", REQ_KEY, myself->name, to->name, REQ_PUBKEY);
+ return true;
+ }
+ char label[25 + strlen(myself->name) + strlen(to->name)];
+ snprintf(label, sizeof label, "tinc UDP key expansion %s %s", myself->name, to->name);
+ return sptps_start(&to->sptps, to, true, true, myself->connection->ecdsa, to->ecdsa, label, sizeof label, send_initial_sptps_data, receive_sptps_record);
}
+
return send_request(to->nexthop->connection, "%d %s %s", REQ_KEY, myself->name, to->name);
}
return true;
}
- char pubkey[4096];
+ char pubkey[MAX_STRING_SIZE];
if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, pubkey) != 1 || !ecdsa_set_base64_public_key(&from->ecdsa, pubkey)) {
logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "ANS_PUBKEY", from->name, from->hostname, "invalid pubkey");
return true;
return true;
}
+ case REQ_KEY: {
+ if(!node_read_ecdsa_public_key(from)) {
+ logger(DEBUG_ALWAYS, LOG_DEBUG, "No ECDSA key known for %s (%s)", from->name, from->hostname);
+ send_request(from->nexthop->connection, "%d %s %s %d", REQ_KEY, myself->name, from->name, REQ_PUBKEY);
+ return true;
+ }
+ }
+
+ case REQ_SPTPS: {
+ char buf[MAX_STRING_SIZE];
+ if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, buf) != 1) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "REQ_KEY", from->name, from->hostname, "invalid SPTPS data");
+ return true;
+ }
+ int len = b64decode(buf, buf, strlen(buf));
+
+
+ char label[25 + strlen(from->name) + strlen(myself->name)];
+ snprintf(label, sizeof label, "tinc UDP key expansion %s %s", from->name, myself->name);
+ sptps_start(&from->sptps, from, false, true, myself->connection->ecdsa, from->ecdsa, label, sizeof label, send_sptps_data, receive_sptps_record);
+ sptps_receive_data(&from->sptps, buf, len);
+ return true;
+ }
+
default:
logger(DEBUG_ALWAYS, LOG_ERR, "Unknown extended REQ_KEY request from %s (%s): %s", from->name, from->hostname, request);
return true;
return true;
}
-bool send_ans_key_ecdh(node_t *to) {
- int siglen = ecdsa_size(&myself->connection->ecdsa);
- char key[(ECDH_SIZE + siglen) * 2 + 1];
-
- if(!ecdh_generate_public(&to->ecdh, key))
- return false;
-
- if(!ecdsa_sign(&myself->connection->ecdsa, key, ECDH_SIZE, key + ECDH_SIZE))
- return false;
-
- b64encode(key, key, ECDH_SIZE + siglen);
-
- int result = send_request(to->nexthop->connection, "%d %s %s %s %d %d %d %d", ANS_KEY,
- myself->name, to->name, key,
- cipher_get_nid(&myself->incipher),
- digest_get_nid(&myself->indigest),
- (int)digest_length(&myself->indigest),
- myself->incompression);
-
- return result;
-}
-
bool send_ans_key(node_t *to) {
if(experimental && OPTION_VERSION(to->options) >= 2)
- return send_ans_key_ecdh(to);
+ abort();
size_t keylen = cipher_keylength(&myself->incipher);
char key[keylen * 2 + 1];
return send_request(to->nexthop->connection, "%s", request);
}
+ /* SPTPS or old-style key exchange? */
+
+ if(experimental && OPTION_VERSION(from->options) >= 2) {
+ char buf[strlen(key)];
+ int len = b64decode(key, buf, strlen(key));
+
+ if(!sptps_receive_data(&from->sptps, buf, len))
+ logger(DEBUG_ALWAYS, LOG_ERR, "Error processing SPTPS data from %s (%s)", from->name, from->hostname);
+
+ if(from->status.validkey) {
+ if(*address && *port) {
+ logger(DEBUG_PROTOCOL, 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)
+ send_mtu_probe(from);
+ }
+
+ return true;
+ }
+
/* Check and lookup cipher and digest algorithms */
if(!cipher_open_by_nid(&from->outcipher, cipher)) {
from->outcompression = compression;
- /* ECDH or old-style key exchange? */
-
- if(experimental && OPTION_VERSION(from->options) >= 2) {
- /* Check if we already have an ECDSA public key for this node. */
-
- if(!node_read_ecdsa_public_key(from)) {
- logger(DEBUG_ALWAYS, LOG_ERR, "No ECDSA public key known for %s (%s), cannot verify ECDH key exchange!", from->name, from->hostname);
- return true;
- }
-
- int siglen = ecdsa_size(&from->ecdsa);
- int keylen = b64decode(key, key, sizeof key);
-
- if(keylen != ECDH_SIZE + siglen) {
- logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses wrong keylength! %d != %d", from->name, from->hostname, keylen, ECDH_SIZE + siglen);
- return true;
- }
-
- if(ECDH_SHARED_SIZE < cipher_keylength(&from->outcipher)) {
- logger(DEBUG_ALWAYS, LOG_ERR, "ECDH key too short for cipher of %s!", from->name);
- return true;
- }
+ /* Process key */
- if(!ecdsa_verify(&from->ecdsa, key, ECDH_SIZE, key + ECDH_SIZE)) {
- logger(DEBUG_ALWAYS, LOG_ERR, "Possible intruder %s (%s): %s", from->name, from->hostname, "invalid ECDSA signature");
- return true;
- }
-
- if(!from->ecdh) {
- if(!send_ans_key_ecdh(from))
- return true;
- }
+ keylen = hex2bin(key, key, sizeof key);
- char shared[ECDH_SHARED_SIZE * 2 + 1];
-
- if(!ecdh_compute_shared(&from->ecdh, key, shared))
- return true;
-
- /* Update our crypto end */
-
- size_t mykeylen = cipher_keylength(&myself->incipher);
- size_t hiskeylen = cipher_keylength(&from->outcipher);
-
- char *mykey;
- char *hiskey;
- char *seed;
-
- if(strcmp(myself->name, from->name) < 0) {
- mykey = key;
- hiskey = key + mykeylen * 2;
- xasprintf(&seed, "tinc UDP key expansion %s %s", myself->name, from->name);
- } else {
- mykey = key + hiskeylen * 2;
- hiskey = key;
- xasprintf(&seed, "tinc UDP key expansion %s %s", from->name, myself->name);
- }
-
- if(!prf(shared, ECDH_SHARED_SIZE, seed, strlen(seed), key, hiskeylen * 2 + mykeylen * 2))
- return true;
-
- free(seed);
-
- cipher_open_by_nid(&from->incipher, cipher_get_nid(&myself->incipher));
- digest_open_by_nid(&from->indigest, digest_get_nid(&myself->indigest), digest_length(&myself->indigest));
- from->incompression = myself->incompression;
-
- cipher_set_key(&from->incipher, mykey, false);
- digest_set_key(&from->indigest, mykey + mykeylen, mykeylen);
-
- cipher_set_key(&from->outcipher, hiskey, true);
- digest_set_key(&from->outdigest, hiskey + hiskeylen, hiskeylen);
-
- // Reset sequence number and late packet window
- mykeyused = true;
- from->received_seqno = 0;
- if(replaywin)
- memset(from->late, 0, replaywin);
-
- if(strcmp(myself->name, from->name) < 0)
- memmove(key, key + mykeylen * 2, hiskeylen * 2);
- } else {
- keylen = hex2bin(key, key, sizeof key);
-
- if(keylen != cipher_keylength(&from->outcipher)) {
- logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses wrong keylength!", from->name, from->hostname);
- return true;
- }
+ if(keylen != cipher_keylength(&from->outcipher)) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses wrong keylength!", from->name, from->hostname);
+ return true;
+ }
- /* Update our copy of the origin's packet key */
+ /* Update our copy of the origin's packet key */
- cipher_set_key(&from->outcipher, key, true);
- digest_set_key(&from->outdigest, key, keylen);
- }
+ cipher_set_key(&from->outcipher, key, true);
+ digest_set_key(&from->outdigest, key, keylen);
from->status.validkey = true;
from->sent_seqno = 0;