X-Git-Url: https://tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fnet_packet.c;h=8313a54fd0e142c7a9106bd04bd43ddf3b5f661c;hb=1a7a9078c093f77950192c32be009bbe463fe372;hp=5ebfcce13ab73f5417ee9dd22e87b70051245e05;hpb=de14308840a96060d700c93117789e83ec948c01;p=tinc

diff --git a/src/net_packet.c b/src/net_packet.c
index 5ebfcce1..8313a54f 100644
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -260,7 +260,7 @@ static bool try_mac(node_t *n, const vpn_packet_t *inpkt) {
 	if(!n->status.validkey_in || !digest_active(n->indigest) || inpkt->len < sizeof(seqno_t) + digest_length(n->indigest))
 		return false;
 
-	return digest_verify(n->indigest, SEQNO(inpkt), inpkt->len - digest_length(n->indigest), DATA(inpkt) + inpkt->len - digest_length(n->indigest));
+	return digest_verify(n->indigest, inpkt->data, inpkt->len - digest_length(n->indigest), inpkt->data + inpkt->len - digest_length(n->indigest));
 #endif
 }
 
@@ -288,7 +288,14 @@ static bool receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
 		n->status.udppacket = false;
 
 		if(!result) {
-			logger(DEBUG_TRAFFIC, LOG_ERR, "Got bad packet from %s (%s)", n->name, n->hostname);
+			/* Uh-oh. It might be that the tunnel is stuck in some corrupted state,
+			   so let's restart SPTPS in case that helps. But don't do that too often
+			   to prevent storms, and because that would make life a little too easy
+			   for external attackers trying to DoS us. */
+			if(n->last_req_key < now.tv_sec - 10) {
+				logger(DEBUG_PROTOCOL, LOG_ERR, "Failed to decode raw TCP packet from %s (%s), restarting SPTPS", n->name, n->hostname);
+				send_req_key(n);
+			}
 			return false;
 		}
 		return true;
@@ -428,6 +435,57 @@ 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(!sptps_receive_data(&from->sptps, data, len)) {
+		/* Uh-oh. It might be that the tunnel is stuck in some corrupted state,
+		   so let's restart SPTPS in case that helps. But don't do that too often
+		   to prevent storms. */
+		if(from->last_req_key < now.tv_sec - 10) {
+			logger(DEBUG_PROTOCOL, LOG_ERR, "Failed to decode raw TCP packet from %s (%s), restarting SPTPS", from->name, from->hostname);
+			send_req_key(from);
+		}
+		return true;
+	}
+
+	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;
@@ -690,11 +748,21 @@ 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(type != SPTPS_HANDSHAKE && (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,
-		   to ensure we get to learn the reflexive UDP address. */
-		if(from == myself && !to->status.validkey) {
+		/* If this is a handshake packet, use ANS_KEY instead of REQ_KEY, for two reasons:
+		    - We don't want intermediate nodes to switch to UDP to relay these packets;
+		    - ANS_KEY allows us to learn the reflexive UDP address. */
+		if(type == SPTPS_HANDSHAKE) {
 			to->incompression = myself->incompression;
 			return send_request(to->nexthop->connection, "%d %s %s %s -1 -1 -1 %d", ANS_KEY, from->name, to->name, buf, to->incompression);
 		} else {
@@ -725,7 +793,7 @@ 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