Introduce raw TCP SPTPS packet transport.

[tinc] / src / net_packet.c

diff --git a/src/net_packet.c b/src/net_packet.c
index 5ebfcce..1fdc0fe 100644 (file)
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -428,6 +428,51 @@ void receive_tcppacket(connection_t *c, const char *buffer, int len) {
        receive_packet(c->node, &outpkt);
 }
 
+bool receive_tcppacket_sptps(connection_t *c, const char *data, int len) {
+       if (len < sizeof(node_id_t) + sizeof(node_id_t)) {
+               logger(DEBUG_ALWAYS, LOG_ERR, "Got too short TCP SPTPS packet from %s (%s)", c->name, c->hostname);
+               return false;
+       }
+
+       node_t *to = lookup_node_id((node_id_t *)data);
+       data += sizeof(node_id_t); len -= sizeof(node_id_t);
+       if(!to) {
+               logger(DEBUG_PROTOCOL, LOG_ERR, "Got TCP SPTPS packet from %s (%s) with unknown destination ID", c->name, c->hostname);
+               return true;
+       }
+
+       node_t *from = lookup_node_id((node_id_t *)data);
+       data += sizeof(node_id_t); len -= sizeof(node_id_t);
+       if(!from) {
+               logger(DEBUG_PROTOCOL, LOG_ERR, "Got TCP SPTPS packet from %s (%s) with unknown source ID", c->name, c->hostname);
+               return true;
+       }
+
+       /* Help the sender reach us over UDP.
+          Note that we only do this if we're the destination or the static relay;
+          otherwise every hop would initiate its own UDP info message, resulting in elevated chatter. */
+       if(to->via == myself)
+               send_udp_info(myself, from);
+
+       /* If we're not the final recipient, relay the packet. */
+
+       if(to != myself) {
+               send_sptps_data(to, from, 0, data, len);
+               try_tx(to, true);
+               return true;
+       }
+
+       /* The packet is for us */
+
+       if(!from->status.validkey) {
+               logger(DEBUG_PROTOCOL, LOG_ERR, "Got SPTPS packet from %s (%s) but we don't have a valid key yet", from->name, from->hostname);
+               return true;
+       }
+       sptps_receive_data(&from->sptps, data, len);
+       send_mtu_info(myself, from, MTU);
+       return true;
+}
+
 static void send_sptps_packet(node_t *n, vpn_packet_t *origpkt) {
        if(!n->status.validkey && !n->connection)
                return;
@@ -690,6 +735,15 @@ bool send_sptps_data(node_t *to, node_t *from, int type, const void *data, size_
        /* Send it via TCP if it is a handshake packet, TCPOnly is in use, this is a relay packet that the other node cannot understand, or this packet is larger than the MTU. */
 
        if(type == SPTPS_HANDSHAKE || tcponly || (!direct && !relay_supported) || (type != PKT_PROBE && (len - SPTPS_DATAGRAM_OVERHEAD) > relay->minmtu)) {
+               if((from != myself || to->status.validkey) && (to->nexthop->connection->options >> 24) >= 7) {
+                       char buf[len + sizeof to->id + sizeof from->id]; char* buf_ptr = buf;
+                       memcpy(buf_ptr, &to->id, sizeof to->id); buf_ptr += sizeof to->id;
+                       memcpy(buf_ptr, &from->id, sizeof from->id); buf_ptr += sizeof from->id;
+                       memcpy(buf_ptr, data, len); buf_ptr += len;
+                       logger(DEBUG_TRAFFIC, LOG_INFO, "Sending packet from %s (%s) to %s (%s) via %s (%s) (TCP)", from->name, from->hostname, to->name, to->hostname, to->nexthop->name, to->nexthop->hostname);
+                       return send_sptps_tcppacket(to->nexthop->connection, buf, sizeof buf);
+               }
+
                char buf[len * 4 / 3 + 5];
                b64encode(data, buf, len);
                /* If no valid key is known yet, send the packets using ANS_KEY requests,
@@ -725,7 +779,7 @@ bool send_sptps_data(node_t *to, node_t *from, int type, const void *data, size_
                choose_local_address(relay, &sa, &sock);
        if(!sa)
                choose_udp_address(relay, &sa, &sock);
-       logger(DEBUG_TRAFFIC, LOG_INFO, "Sending packet from %s (%s) to %s (%s) via %s (%s)", from->name, from->hostname, to->name, to->hostname, relay->name, relay->hostname);
+       logger(DEBUG_TRAFFIC, LOG_INFO, "Sending packet from %s (%s) to %s (%s) via %s (%s) (UDP)", from->name, from->hostname, to->name, to->hostname, relay->name, relay->hostname);
        if(sendto(listen_socket[sock].udp.fd, buf, buf_ptr - buf, 0, &sa->sa, SALEN(sa->sa)) < 0 && !sockwouldblock(sockerrno)) {
                if(sockmsgsize(sockerrno)) {
                        // Compensate for SPTPS overhead