Fix Windows device asynchronous write behavior.

[tinc] / src / net_packet.c

diff --git a/src/net_packet.c b/src/net_packet.c
index e9e2172..8dba325 100644 (file)
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -257,7 +257,7 @@ static bool try_mac(node_t *n, const vpn_packet_t *inpkt) {
 #ifdef DISABLE_LEGACY
        return false;
 #else
-       if(!digest_active(n->indigest) || inpkt->len < sizeof(seqno_t) + digest_length(n->indigest))
+       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));
@@ -958,6 +958,7 @@ static length_t choose_initial_maxmtu(node_t *n) {
                mtu -= SPTPS_DATAGRAM_OVERHEAD;
                if((n->options >> 24) >= 4)
                        mtu -= sizeof(node_id_t) + sizeof(node_id_t);
+#ifndef DISABLE_LEGACY
        } else {
                mtu -= digest_length(n->outdigest);
 
@@ -977,6 +978,7 @@ static length_t choose_initial_maxmtu(node_t *n) {
                }
 
                mtu -= 4; // seqno
+#endif
        }
 
        if (mtu < 512) {
@@ -1123,23 +1125,31 @@ static void try_tx_sptps(node_t *n, bool mtu) {
 
        try_sptps(n);
 
-       /* Do we need to relay packets? */
+       /* Do we need to statically relay packets? */
 
        node_t *via = (n->via == myself) ? n->nexthop : n->via;
 
-       /* If the relay doesn't support SPTPS, everything goes via TCP anyway. */
+       /* If the static relay doesn't support SPTPS, everything goes via TCP anyway. */
 
        if((via->options >> 24) < 4)
                return;
 
-       /* If we do have a relay, try everything with that one instead. */
+       /* If we do have a static relay, try everything with that one instead. */
 
        if(via != n)
-               return try_tx_sptps(via, mtu);
+               try_tx_sptps(via, mtu);
+
+       /* Otherwise, try to establish UDP connectivity. */
 
        try_udp(n);
        if(mtu)
                try_mtu(n);
+
+       /* If we don't have UDP connectivity (yet), we need to use a dynamic relay (nexthop)
+          while we try to establish direct connectivity. */
+
+       if(!n->status.udp_confirmed && n != n->nexthop && (n->nexthop->options >> 24) >= 4)
+               try_tx_sptps(n->nexthop, mtu);
 }
 
 static void try_tx_legacy(node_t *n, bool mtu) {
@@ -1263,33 +1273,52 @@ void broadcast_packet(const node_t *from, vpn_packet_t *packet) {
        }
 }
 
+/* We got a packet from some IP address, but we don't know who sent it.  Try to
+   verify the message authentication code against all active session keys.
+   Since this is actually an expensive operation, we only do a full check once
+   a minute, the rest of the time we only check against nodes for which we know
+   an IP address that matches the one from the packet.  */
+
 static node_t *try_harder(const sockaddr_t *from, const vpn_packet_t *pkt) {
-       node_t *n = NULL;
+       node_t *match = NULL;
        bool hard = false;
        static time_t last_hard_try = 0;
 
-       for splay_each(edge_t, e, edge_weight_tree) {
-               if(!e->to->status.reachable || e->to == myself)
+       for splay_each(node_t, n, node_tree) {
+               if(!n->status.reachable || n == myself)
+                       continue;
+
+               if((n->status.sptps && !n->sptps.instate) || !n->status.validkey_in)
                        continue;
 
-               if(sockaddrcmp_noport(from, &e->address)) {
+               bool soft = false;
+
+               for splay_each(edge_t, e, n->edge_tree) {
+                       if(!e->reverse)
+                               continue;
+                       if(!sockaddrcmp_noport(from, &e->reverse->address)) {
+                               soft = true;
+                               break;
+                       }
+               }
+
+               if(!soft) {
                        if(last_hard_try == now.tv_sec)
                                continue;
                        hard = true;
                }
 
-               if(!try_mac(e->to, pkt))
+               if(!try_mac(n, pkt))
                        continue;
 
-               n = e->to;
+               match = n;
                break;
        }
 
        if(hard)
                last_hard_try = now.tv_sec;
 
-       last_hard_try = now.tv_sec;
-       return n;
+       return match;
 }
 
 void handle_incoming_vpn_data(void *data, int flags) {
@@ -1319,6 +1348,9 @@ void handle_incoming_vpn_data(void *data, int flags) {
 
        node_t *n = lookup_node_udp(&addr);
 
+       if(n && !n->status.udp_confirmed)
+               n = NULL; // Don't believe it if we don't have confirmation yet.
+
        if(!n) {
                // It might be from a 1.1 node, which might have a source ID in the packet.
                pkt.offset = 2 * sizeof(node_id_t);
@@ -1364,6 +1396,7 @@ skip_harder:
 
                if(to != myself) {
                        send_sptps_data_priv(to, n, 0, DATA(&pkt), pkt.len - 2 * sizeof(node_id_t));
+                       try_tx_sptps(n, true);
                        return;
                }
        } else {