Try all known addresses of node during PMTU discovery, now also for SPTPS.
authorGuus Sliepen <guus@tinc-vpn.org>
Sat, 17 Nov 2012 21:48:06 +0000 (22:48 +0100)
committerGuus Sliepen <guus@tinc-vpn.org>
Sat, 17 Nov 2012 21:48:06 +0000 (22:48 +0100)
src/net_packet.c

index 2abe16e..dbf361f 100644 (file)
@@ -438,6 +438,80 @@ static void send_sptps_packet(node_t *n, vpn_packet_t *origpkt) {
        return;
 }
 
+static void choose_udp_address(const node_t *n, const sockaddr_t **sa, int *sock) {
+       /* Latest guess */
+       *sa = &n->address;
+       *sock = n->sock;
+
+       /* If the UDP address is confirmed, use it. */
+       if(n->status.udp_confirmed)
+               return;
+
+       /* Otherwise, go through the list of known addresses of
+          this node. The first address we try is always the
+          one in n->address; that could be set to the node's
+          reflexive UDP address discovered during key
+          exchange. The other known addresses are those found
+          in edges to this node. */
+
+
+       int i = 0;
+       int j = rand() % n->edge_tree->count;
+       edge_t *candidate = NULL;
+
+       for splay_each(edge_t, e, edge_weight_tree) {
+               if(e->to != n)
+                       continue;
+               i++;
+               if(!candidate || i == j)
+                       candidate = e;
+       }
+
+       if(candidate) {
+               *sa = &candidate->address;
+               *sock = rand() % listen_sockets;
+       }
+
+       /* Make sure we have a suitable socket for the chosen address */
+       if(listen_socket[*sock].sa.sa.sa_family != (*sa)->sa.sa_family) {
+               for(int i = 0; i < listen_sockets; i++) {
+                       if(listen_socket[i].sa.sa.sa_family == (*sa)->sa.sa_family) {
+                               *sock = i;
+                               break;
+                       }
+               }
+       }
+}
+
+static void choose_broadcast_address(const node_t *n, const sockaddr_t **sa, int *sock) {
+       static sockaddr_t broadcast_ipv4 = {
+               .in = {
+                       .sin_family = AF_INET,
+                       .sin_addr.s_addr = -1,
+               }
+       };
+
+       static sockaddr_t broadcast_ipv6 = {
+               .in6 = {
+                       .sin6_family = AF_INET6,
+                       .sin6_addr.s6_addr[0x0] = 0xff,
+                       .sin6_addr.s6_addr[0x1] = 0x02,
+                       .sin6_addr.s6_addr[0xf] = 0x01,
+               }
+       };
+
+       *sock = rand() % listen_sockets;
+
+       if(listen_socket[*sock].sa.sa.sa_family == AF_INET6) {
+               broadcast_ipv6.in6.sin6_port = n->prevedge->address.in.sin_port;
+               broadcast_ipv6.in6.sin6_scope_id = listen_socket[*sock].sa.in6.sin6_scope_id;
+               *sa = &broadcast_ipv6;
+       } else {
+               broadcast_ipv4.in.sin_port = n->prevedge->address.in.sin_port;
+               *sa = &broadcast_ipv4;
+       }
+}
+
 static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
        vpn_packet_t pkt1, pkt2;
        vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 };
@@ -534,84 +608,15 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
 
        /* Send the packet */
 
-       sockaddr_t *sa;
+       const sockaddr_t *sa;
        int sock;
-       sockaddr_t broadcast;
 
        /* Overloaded use of priority field: -1 means local broadcast */
 
-       if(origpriority == -1 && n->prevedge) {
-               sock = rand() % listen_sockets;
-               memset(&broadcast, 0, sizeof broadcast);
-               if(listen_socket[sock].sa.sa.sa_family == AF_INET6) {
-                       broadcast.in6.sin6_family = AF_INET6;
-                       broadcast.in6.sin6_addr.s6_addr[0x0] = 0xff;
-                       broadcast.in6.sin6_addr.s6_addr[0x1] = 0x02;
-                       broadcast.in6.sin6_addr.s6_addr[0xf] = 0x01;
-                       broadcast.in6.sin6_port = n->prevedge->address.in.sin_port;
-                       broadcast.in6.sin6_scope_id = listen_socket[sock].sa.in6.sin6_scope_id;
-               } else {
-                       broadcast.in.sin_family = AF_INET;
-                       broadcast.in.sin_addr.s_addr = -1;
-                       broadcast.in.sin_port = n->prevedge->address.in.sin_port;
-               }
-               sa = &broadcast;
-       } else {
-               if(origpriority == -1)
-                       origpriority = 0;
-
-               if(n->status.udp_confirmed) {
-                       /* Address of this node is confirmed, so use it. */
-                       sa = &n->address;
-                       sock = n->sock;
-               } else {
-                       /* Otherwise, go through the list of known addresses of
-                          this node. The first address we try is always the
-                          one in n->address; that could be set to the node's
-                          reflexive UDP address discovered during key
-                          exchange. The other known addresses are those found
-                          in edges to this node. */
-
-                       static unsigned int i;
-                       int j = 0;
-                       edge_t *candidate = NULL;
-
-                       if(i) {
-                               for splay_each(edge_t, e, edge_weight_tree) {
-                                       if(e->to != n)
-                                               continue;
-                                       j++;
-                                       if(!candidate || j == i)
-                                               candidate = e;
-                               }
-                       }
-
-                       if(!candidate) {
-                               sa = &n->address;
-                               sock = n->sock;
-                       } else {
-                               sa = &candidate->address;
-                               sock = rand() % listen_sockets;
-                       }
-
-                       if(i++)
-                               if(i > j)
-                                       i = 0;
-               }
-       }
-
-       /* Determine which socket we have to use */
-
-       if(sa->sa.sa_family != listen_socket[sock].sa.sa.sa_family)
-               for(sock = 0; sock < listen_sockets; sock++)
-                       if(sa->sa.sa_family == listen_socket[sock].sa.sa.sa_family)
-                               break;
-
-       if(sock >= listen_sockets)
-               sock = 0;
-
-       if(!n->status.udp_confirmed)
-               n->sock = sock;
+       if(origpriority == -1 && n->prevedge)
+               choose_broadcast_address(n, &sa, &sock);
+       else
+               choose_udp_address(n, &sa, &sock);
 
 #if defined(SOL_IP) && defined(IP_TOS)
        if(priorityinheritance && origpriority != priority
@@ -623,9 +628,7 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
        }
 #endif
 
-       socklen_t sl = SALEN(n->address.sa);
-
-       if(sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, &sa->sa, sl) < 0 && !sockwouldblock(sockerrno)) {
+       if(sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, &sa->sa, SALEN(sa->sa)) < 0 && !sockwouldblock(sockerrno)) {
                if(sockmsgsize(sockerrno)) {
                        if(n->maxmtu >= origlen)
                                n->maxmtu = origlen - 1;
@@ -657,15 +660,12 @@ bool send_sptps_data(void *handle, uint8_t type, const char *data, size_t len) {
 
        /* Otherwise, send the packet via UDP */
 
-       struct sockaddr *sa;
-       socklen_t sl;
+       const sockaddr_t *sa;
        int sock;
 
-       sa = &(to->address.sa);
-       sl = SALEN(to->address.sa);
-       sock = to->sock;
+       choose_udp_address(to, &sa, &sock);
 
-       if(sendto(listen_socket[sock].udp, data, len, 0, sa, sl) < 0 && !sockwouldblock(sockerrno)) {
+       if(sendto(listen_socket[sock].udp, data, len, 0, &sa->sa, SALEN(sa->sa)) < 0 && !sockwouldblock(sockerrno)) {
                if(sockmsgsize(sockerrno)) {
                        if(to->maxmtu >= len)
                                to->maxmtu = len - 1;