pex: create pex host from update responses

When a host responds to a broadcast update request, responses might be
overlapping. If the responses to the broadcast request can't be processed
properly, ensure that a unicast request to each responder is also
attempted. This increases the update reliability.

Signed-off-by: Felix Fietkau <nbd@nbd.name>

diff --git a/pex.c b/pex.c
index 8fb9c3c8bf1e957da562169b64f4918eac4df57a..cfd238fcd111d714ccb27c2ac88a75b12f09340a 100644 (file)
--- a/pex.c
+++ b/pex.c
@@ -1015,6 +1015,9 @@ global_pex_recv(void *msg, size_t msg_len, struct sockaddr_in6 *addr)
        void *data;
        int addr_len;
        int ep_idx = ENDPOINT_TYPE_ENDPOINT_NOTIFY;
+       union network_endpoint host_ep = {
+               .in6 = *addr
+       };
 
        if (stun_msg_is_valid(msg, msg_len)) {
                avl_for_each_element(&networks, net, node)
@@ -1055,6 +1058,9 @@ global_pex_recv(void *msg, size_t msg_len, struct sockaddr_in6 *addr)
                                                addr);
                break;
        case PEX_MSG_UPDATE_RESPONSE:
+               if (net->pex.num_hosts < NETWORK_PEX_HOSTS_LIMIT)
+                       network_pex_create_host(net, &host_ep, 20);
+               fallthrough;
        case PEX_MSG_UPDATE_RESPONSE_DATA:
        case PEX_MSG_UPDATE_RESPONSE_NO_DATA:
                network_pex_recv_update_response(net, data, hdr->len, addr, hdr->opcode);
@@ -1077,9 +1083,6 @@ global_pex_recv(void *msg, size_t msg_len, struct sockaddr_in6 *addr)
                memcpy(&peer->state.next_endpoint[ep_idx], addr, sizeof(*addr));
                if (hdr->opcode == PEX_MSG_ENDPOINT_PORT_NOTIFY) {
                        struct pex_endpoint_port_notify *port = data;
-                       union network_endpoint host_ep = {
-                               .in6 = *addr
-                       };
 
                        peer->state.next_endpoint[ep_idx].in.sin_port = port->port;
                        if (net->pex.num_hosts < NETWORK_PEX_HOSTS_LIMIT)