X-Git-Url: https://www.tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fnet_packet.c;h=0059b278f5e8dc22c6c7f4db8e6aca9a029e0a4d;hp=1730023d17c6f54c673896bbf4c25faf70b309f7;hb=5dde6461a321ee47b06e33f8203f2acf00a31a51;hpb=3308d13e7e3bf20cfeaf6f2ab17228a9820cea66

diff --git a/src/net_packet.c b/src/net_packet.c
index 1730023d..0059b278 100644
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -13,11 +13,9 @@
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
 
-    You should have received a copy of the GNU General Public License
-    along with this program; if not, write to the Free Software
-    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-
-    $Id$
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
 
 #include "system.h"
@@ -54,15 +52,13 @@
 
 int keylifetime = 0;
 int keyexpires = 0;
-EVP_CIPHER_CTX packet_ctx;
 static char lzo_wrkmem[LZO1X_999_MEM_COMPRESS > LZO1X_1_MEM_COMPRESS ? LZO1X_999_MEM_COMPRESS : LZO1X_1_MEM_COMPRESS];
 
 static void send_udppacket(node_t *, vpn_packet_t *);
 
 #define MAX_SEQNO 1073741824
 
-void send_mtu_probe(node_t *n)
-{
+void send_mtu_probe(node_t *n) {
 	vpn_packet_t packet;
 	int len, i;
 	
@@ -71,6 +67,11 @@ void send_mtu_probe(node_t *n)
 	n->mtuprobes++;
 	n->mtuevent = NULL;
 
+	if(!n->status.reachable) {
+		logger(LOG_DEBUG, _("Trying to send MTU probe to unreachable node %s (%s)"), n->name, n->hostname);
+		return;
+	}
+
 	if(n->mtuprobes >= 10 && !n->minmtu) {
 		ifdebug(TRAFFIC) logger(LOG_INFO, _("No response to MTU probes from %s (%s)"), n->name, n->hostname);
 		return;
@@ -83,7 +84,7 @@ void send_mtu_probe(node_t *n)
 			return;
 		}
 
-		len = n->minmtu + 1 + random() % (n->maxmtu - n->minmtu);
+		len = n->minmtu + 1 + rand() % (n->maxmtu - n->minmtu);
 		if(len < 64)
 			len = 64;
 		
@@ -104,20 +105,19 @@ void send_mtu_probe(node_t *n)
 	event_add(n->mtuevent);
 }
 
-void mtu_probe_h(node_t *n, vpn_packet_t *packet) {
+void mtu_probe_h(node_t *n, vpn_packet_t *packet, length_t len) {
 	ifdebug(TRAFFIC) logger(LOG_INFO, _("Got MTU probe length %d from %s (%s)"), packet->len, n->name, n->hostname);
 
 	if(!packet->data[0]) {
 		packet->data[0] = 1;
 		send_packet(n, packet);
 	} else {
-		if(n->minmtu < packet->len)
-			n->minmtu = packet->len;
+		if(n->minmtu < len)
+			n->minmtu = len;
 	}
 }
 
-static length_t compress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level)
-{
+static length_t compress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) {
 	if(level == 10) {
 		lzo_uint lzolen = MAXSIZE;
 		lzo1x_1_compress(source, len, dest, &lzolen, lzo_wrkmem);
@@ -137,8 +137,7 @@ static length_t compress_packet(uint8_t *dest, const uint8_t *source, length_t l
 	return -1;
 }
 
-static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level)
-{
+static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) {
 	if(level > 9) {
 		lzo_uint lzolen = MAXSIZE;
 		if(lzo1x_decompress_safe(source, len, dest, &lzolen, NULL) == LZO_E_OK)
@@ -158,8 +157,7 @@ static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t
 
 /* VPN packet I/O */
 
-static void receive_packet(node_t *n, vpn_packet_t *packet)
-{
+static void receive_packet(node_t *n, vpn_packet_t *packet) {
 	cp();
 
 	ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Received packet of %d bytes from %s (%s)"),
@@ -168,8 +166,7 @@ static void receive_packet(node_t *n, vpn_packet_t *packet)
 	route(n, packet);
 }
 
-static bool try_mac(const node_t *n, const vpn_packet_t *inpkt)
-{
+static bool try_mac(const node_t *n, const vpn_packet_t *inpkt) {
 	unsigned char hmac[EVP_MAX_MD_SIZE];
 
 	if(!n->indigest || !n->inmaclength || !n->inkey || inpkt->len < sizeof inpkt->seqno + n->inmaclength)
@@ -180,8 +177,7 @@ static bool try_mac(const node_t *n, const vpn_packet_t *inpkt)
 	return !memcmp(hmac, (char *) &inpkt->seqno + inpkt->len - n->inmaclength, n->inmaclength);
 }
 
-static void receive_udppacket(node_t *n, vpn_packet_t *inpkt)
-{
+static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
 	vpn_packet_t pkt1, pkt2;
 	vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 };
 	int nextpkt = 0;
@@ -271,6 +267,8 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt)
 
 	/* Decompress the packet */
 
+	length_t origlen = inpkt->len;
+
 	if(n->incompression) {
 		outpkt = pkt[nextpkt++];
 
@@ -281,6 +279,8 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt)
 		}
 
 		inpkt = outpkt;
+
+		origlen -= MTU/64 + 20;
 	}
 
 	inpkt->priority = 0;
@@ -289,13 +289,12 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt)
 		n->connection->last_ping_time = now;
 
 	if(!inpkt->data[12] && !inpkt->data[13])
-		mtu_probe_h(n, inpkt);
+		mtu_probe_h(n, inpkt, origlen);
 	else
 		receive_packet(n, inpkt);
 }
 
-void receive_tcppacket(connection_t *c, char *buffer, int len)
-{
+void receive_tcppacket(connection_t *c, char *buffer, int len) {
 	vpn_packet_t outpkt;
 
 	cp();
@@ -310,8 +309,7 @@ void receive_tcppacket(connection_t *c, char *buffer, int len)
 	receive_packet(c->node, &outpkt);
 }
 
-static void send_udppacket(node_t *n, vpn_packet_t *origpkt)
-{
+static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
 	vpn_packet_t pkt1, pkt2;
 	vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 };
 	vpn_packet_t *inpkt = origpkt;
@@ -325,6 +323,11 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt)
 
 	cp();
 
+	if(!n->status.reachable) {
+		ifdebug(TRAFFIC) logger(LOG_INFO, _("Trying to send UDP packet to unreachable node %s (%s)"), n->name, n->hostname);
+		return;
+	}
+
 	/* Make sure we have a valid key */
 
 	if(!n->status.validkey) {
@@ -342,9 +345,9 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt)
 		return;
 	}
 
-	if(!n->minmtu && (inpkt->data[12] | inpkt->data[13])) {
+	if(n->options & OPTION_PMTU_DISCOVERY && inpkt->len > n->minmtu && (inpkt->data[12] | inpkt->data[13])) {
 		ifdebug(TRAFFIC) logger(LOG_INFO,
-				_("No minimum MTU established yet for %s (%s), forwarding via TCP"),
+				_("Packet for %s (%s) larger than minimum MTU, forwarding via TCP"),
 				n->name, n->hostname);
 
 		send_tcppacket(n->nexthop->connection, origpkt);
@@ -438,8 +441,7 @@ end:
 /*
   send a packet to the given vpn ip.
 */
-void send_packet(const node_t *n, vpn_packet_t *packet)
-{
+void send_packet(const node_t *n, vpn_packet_t *packet) {
 	node_t *via;
 
 	cp();
@@ -475,8 +477,7 @@ void send_packet(const node_t *n, vpn_packet_t *packet)
 
 /* Broadcast a packet using the minimum spanning tree */
 
-void broadcast_packet(const node_t *from, vpn_packet_t *packet)
-{
+void broadcast_packet(const node_t *from, vpn_packet_t *packet) {
 	avl_node_t *node;
 	connection_t *c;
 
@@ -485,9 +486,15 @@ void broadcast_packet(const node_t *from, vpn_packet_t *packet)
 	ifdebug(TRAFFIC) logger(LOG_INFO, _("Broadcasting packet of %d bytes from %s (%s)"),
 			   packet->len, from->name, from->hostname);
 
-	if(from != myself)
+	if(from != myself) {
 		send_packet(myself, packet);
 
+		// In TunnelServer mode, do not forward broadcast packets.
+                // The MST might not be valid and create loops.
+		if(tunnelserver)
+			return;
+	}
+
 	for(node = connection_tree->head; node; node = node->next) {
 		c = node->data;
 
@@ -520,8 +527,7 @@ static node_t *try_harder(const sockaddr_t *from, const vpn_packet_t *pkt) {
 	return n;
 }
 
-void handle_incoming_vpn_data(int sock)
-{
+void handle_incoming_vpn_data(int sock) {
 	vpn_packet_t pkt;
 	char *hostname;
 	sockaddr_t from;
@@ -533,7 +539,8 @@ void handle_incoming_vpn_data(int sock)
 	pkt.len = recvfrom(sock, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen);
 
 	if(pkt.len < 0) {
-		logger(LOG_ERR, _("Receiving packet failed: %s"), strerror(errno));
+		if(errno != EAGAIN && errno != EINTR)
+			logger(LOG_ERR, _("Receiving packet failed: %s"), strerror(errno));
 		return;
 	}
 
@@ -545,12 +552,14 @@ void handle_incoming_vpn_data(int sock)
 		n = try_harder(&from, &pkt);
 		if(n)
 			update_node_udp(n, &from);
-		else {
+		else ifdebug(PROTOCOL) {
 			hostname = sockaddr2hostname(&from);
 			logger(LOG_WARNING, _("Received UDP packet from unknown source %s"), hostname);
 			free(hostname);
 			return;
 		}
+		else
+			return;
 	}
 
 	receive_udppacket(n, &pkt);