nat: retry partial ingress measurements and keep known-IP anchor replies available

src/routing_layer/nat_detection.c

@@ -626,6 +626,7 @@ static void owner_apply(struct nat_socket *state, uint8_t mapping, uint8_t inbou
                (unsigned long long)state->observer, (unsigned long long)state->helper, state->filter_clean,
                nat_check_reason_name(partial_reason));
     owner_finish(state, NAT_REASON_NONE); state->reason = partial_reason;
+    if (!profile.inbound && mapping != ADDRESS_MAP_DEPENDENT) state->due = get_time_tb() + NAT_RETRY_TB;
 }
 
 static int owner_run(struct nat_socket *state, uint8_t step) {
@@ -1365,6 +1366,8 @@ int nat_detection_ping_allowed(struct NAT_DETECTION *detector, struct ETCP_SOCKE
                     socket->name, (unsigned long long)peer, sockaddr_storage_to_str(source).str);
         return 0;
     }
+    history_load(state);
+    if (contacted(state, source)) return 1; /* Уже известный IP не может испортить испытание незнакомого входа. */
     if (!tag || length != ROUTE_OBSERVE_TAG_SIZE || memcmp(tag, "NAT4UDP!", 8)) return 1;
     uint64_t group_id = read64(tag + 25), round = read64(tag + 17), owner = peer;
     if (state->phase && state->group_id == group_id && state->round == round && (state->helper == peer || state->observer == peer)) return 1;

tests/test_stun_nat.c

@@ -391,7 +391,10 @@ static void test_fallback(void) {
     assert(socket->address_profile.source == ADDRESS_SOURCE_NONE && !socket->address_profile.mapping && !socket->address_profile.inbound);
     assert(!memcmp(&socket->address_profile, &duplicate->address_profile, sizeof(socket->address_profile)));
     assert(!socket->nat_addr.ss_family && !duplicate->nat_addr.ss_family);
-    struct nat_check_status status; assert(!nat_detection_get_status(owner->nat_det, socket, &status));
+    struct nat_check_status status;
+    end = get_time_tb() + 30000;
+    do { test_clock_poll(nf.ua, 1000); assert(!nat_detection_get_status(owner->nat_det, socket, &status)); }
+    while (get_time_tb() < end && status.reason != NAT_REASON_NO_OBSERVER);
     assert(status.reason == NAT_REASON_NO_OBSERVER);
     struct TOPO_NODE* snapshot = topo_node_registry_find(owner->topo_groups, owner->node_id);
     assert(snapshot && !topo_node_verify(snapshot));