tcp_proxy: fix throughput (tx_queue backpressure) + connect timeout + integration test

- Router: unified service delivery format [svc_id][src][dst][payload] (end-to-end src/dst from SVC_ROUTE header)
- tcp_proxy_client: replace single tx_buf drop-on-backpressure with bounded tx_queue + send_q waiter + retry timer (no data loss, bulk window reopen — removes 62.5ms delayed-ACK stall)
- tcp_io: configurable connect timeout (tcp_conn_set_connect_timeout)
- tcp_proxy_server: connect_timeout config option (ms, default 2000, 0=off)
- check.sh: run tcp_proxy_full integration test with sudo (skip if passwordless sudo unavailable)
- test_tcp_io: connect timeout unit test; docs (lwip_nuances.md)

tests/Makefile.am

@@ -460,3 +460,8 @@ check-local: $(check_PROGRAMS)
 		echo "Run 'cat $(TEST_LOG_DIR)/<test>.log' to see details"; \
 		exit 1; \
 	fi
+
+# Интеграционный тест tcp_proxy_full (требует sudo, TUN, iptables). Запускается из check.sh.
+.PHONY: check-proxy
+check-proxy:
+	@cd $(srcdir)/tcp_proxy_full && bash run_test.sh

tests/tcp_proxy_full/client.conf

@@ -1,5 +1,5 @@
 [global]
-my_node_id=0xAAAA000000000002
+my_node_id=0x5a77374f79310824
 my_private_key=704f2e012c8fa8768130cb0f988a997dccb628372bc5ceccacc78dcbfec5916f
 my_public_key=b3193173def895bd0fcea6f86af077c7d77216f10395275f627ac18242ec0f01
 tun_ip=10.200.20.1/24
@@ -12,14 +12,14 @@ type=public
 
 [client: c1]
 keepalive=1
-link=s1:127.0.0.1:15001
-peer_public_key=ce8871f07fa056c636d297115f231b08c29cdf94e0d440fce83a07c34416d36a
+link=s1:127.0.0.1:15003
+peer_public_key=23ea42d345a0efbcfaab4f47c27bf6da05e3682e27a667ba60a16645ce2c9024
 
 [tcp_proxy_client]
 enabled=yes
 tun_name=tun_test_proxy
 tun_ip=10.200.30.1
-via_node=0xAAAA000000000001
+via_node=0x4239ac368c0df079
 
 [debug]
 connection=info
@@ -27,3 +27,5 @@ socket=info
 general=info
 traffic=info
 tun=info
+proxy=debug
+etcp_route=debug

tests/tcp_proxy_full/exit.conf

@@ -1,5 +1,5 @@
 [global]
-my_node_id=0xAAAA000000000001
+my_node_id=0x4239ac368c0df079
 my_private_key=38240cb82199e504686507f11f6eaa4f740fde6f0c425c495e49a523019a5d68
 my_public_key=ce8871f07fa056c636d297115f231b08c29cdf94e0d440fce83a07c34416d36a
 tun_ip=10.200.10.1/24
@@ -20,3 +20,5 @@ enabled=yes
 connection=info
 socket=info
 traffic=info
+proxy=debug
+etcp_route=debug

tests/tcp_proxy_full/intermediate.conf

@@ -0,0 +1,28 @@
+[global]
+my_node_id=0x628471cde1291456
+my_private_key=2012fcb6f33004ee64c899a229c54619ed89f83d8fe7e003c4d2eca43c453b58
+my_public_key=23ea42d345a0efbcfaab4f47c27bf6da05e3682e27a667ba60a16645ce2c9024
+tun_ip=10.200.40.1/24
+tun_ifname=tun_test_inter
+debug_level=error
+
+[server: s1]
+addr=127.0.0.1:15003
+type=public
+
+[allowed_keys]
+allow_all=1
+
+[client: c1]
+keepalive=1
+link=s1:127.0.0.1:15001
+peer_public_key=ce8871f07fa056c636d297115f231b08c29cdf94e0d440fce83a07c34416d36a
+
+[debug]
+connection=info
+socket=info
+general=info
+traffic=info
+    etcp_route=debug
+    proxy=debug
+

tests/tcp_proxy_full/run_test.sh

@@ -1,9 +1,9 @@
 #!/bin/bash
 # run_test.sh — интеграционный тест tcp_proxy (transparent proxy)
 #
-# Трафик:
+# Топология (3 узла, трафик идёт через промежуточный узел транзитом):
 #   tcp_client.py (SO_MARK=1, dest=10.200.100.N) → table 100 → tun_test_proxy
-#     → tcp_proxy(lwIP) → ETCP → exit(remote_proxy)
+#     → tcp_proxy(lwIP, клиент) → ETCP → intermediate (транзит) → ETCP → exit
 #     → connect(10.200.100.N) → iptables DNAT (!mark=1) → 127.0.0.1 → echo → обратно
 #
 # Запуск: sudo ./run_test.sh
@@ -41,6 +41,9 @@ setup_net() {
         iptables -t nat -C OUTPUT -d "10.200.100.${i}" -p tcp -m mark ! --mark 1 -j DNAT --to-destination 127.0.0.1:"$ECHO_PORT" 2>/dev/null \
             || iptables -t nat -A OUTPUT -d "10.200.100.${i}" -p tcp -m mark ! --mark 1 -j DNAT --to-destination 127.0.0.1:"$ECHO_PORT"
     done
+    # conn_refused: .99 → порт без слушателя, exit получает ECONNREFUSED (иначе SYN уходит в tun_test_proxy и зацикливается)
+    iptables -t nat -C OUTPUT -d 10.200.100.99 -p tcp -m mark ! --mark 1 -j DNAT --to-destination 127.0.0.1:"$REFUSED_PORT" 2>/dev/null \
+        || iptables -t nat -A OUTPUT -d 10.200.100.99 -p tcp -m mark ! --mark 1 -j DNAT --to-destination 127.0.0.1:"$REFUSED_PORT"
     echo "  Done"
 }
 
@@ -63,6 +66,7 @@ cleanup_net() {
     for i in $(seq 1 $N_IP); do
         iptables -t nat -D OUTPUT -d "10.200.100.${i}" -p tcp -m mark ! --mark 1 -j DNAT --to-destination 127.0.0.1:"$ECHO_PORT" 2>/dev/null || true
     done
+    iptables -t nat -D OUTPUT -d 10.200.100.99 -p tcp -m mark ! --mark 1 -j DNAT --to-destination 127.0.0.1:"$REFUSED_PORT" 2>/dev/null || true
     ip rule del fwmark 1 priority 199 table 100 2>/dev/null || true
     ip route del 10.200.100.0/24 dev tun_test_proxy table 100 2>/dev/null || true
     ip route del 10.200.100.0/24 dev tun_test_proxy 2>/dev/null || true
@@ -75,18 +79,22 @@ cleanup_net() {
 cleanup() {
     echo ""; echo "=== Cleanup ==="
     kill $EXIT_PID 2>/dev/null || true
+    kill $INTER_PID 2>/dev/null || true
     kill $CLIENT_PID 2>/dev/null || true
     kill $ECHO_PID 2>/dev/null || true
     wait $EXIT_PID 2>/dev/null || true
+    wait $INTER_PID 2>/dev/null || true
     wait $CLIENT_PID 2>/dev/null || true
     wait $ECHO_PID 2>/dev/null || true
     sleep 0.5; cleanup_net
 }
 
 wait_for_etcp() {
-    for i in $(seq 1 30); do
-        grep -q "Connection established\|initialized and marked as UP (client)" "$LOG_DIR/exit_utun.log" 2>/dev/null && return 0
-        grep -q "initialized and marked as UP (client)" "$LOG_DIR/client_utun.log" 2>/dev/null && return 0
+    for i in $(seq 1 40); do
+        grep -q "Connection UP" "$LOG_DIR/exit_utun.log" 2>/dev/null \
+            && grep -q "Connection UP" "$LOG_DIR/intermediate_utun.log" 2>/dev/null \
+            && grep -q "Connection UP" "$LOG_DIR/client_utun.log" 2>/dev/null \
+            && return 0
         sleep 0.5
     done
     return 1
@@ -202,6 +210,10 @@ echo "Starting utun exit ..."
 "$UTUN_BIN" -c "$SCRIPT_DIR/exit.conf" -f -l "$LOG_DIR/exit_utun.log" >"$LOG_DIR/exit_stdout.log" 2>&1 &
 EXIT_PID=$!
 
+echo "Starting utun intermediate ..."
+"$UTUN_BIN" -c "$SCRIPT_DIR/intermediate.conf" -f -l "$LOG_DIR/intermediate_utun.log" >"$LOG_DIR/intermediate_stdout.log" 2>&1 &
+INTER_PID=$!
+
 echo "Starting utun client ..."
 "$UTUN_BIN" -c "$SCRIPT_DIR/client.conf" -f -l "$LOG_DIR/client_utun.log" >"$LOG_DIR/client_stdout.log" 2>&1 &
 CLIENT_PID=$!
@@ -216,15 +228,15 @@ echo "ETCP ready"; sleep 1
 
 echo ""; echo "=== Running tests ==="
 
-# 1: stress first (catch resource leaks)
-run_stress && ((++PASS)) || ((++FAIL))
-sleep 2
-
-# 2: basic_1mb
+# 1: basic_1mb СНАЧАЛА (изолируем от стресса, чтобы понять — падает ли 1MB сам по себе)
 run_test basic_1mb --host 10.200.100.1 --port "$ECHO_PORT" --size 1048576 --verify --timeout 10 \
     && ((++PASS)) || ((++FAIL))
 sleep 1
 
+# 2: stress (catch resource leaks)
+run_stress && ((++PASS)) || ((++FAIL))
+sleep 2
+
 # 3: concurrent_5
 run_concurrent concurrent_5 5 204800 && ((++PASS)) || ((++FAIL))
 sleep 1

tests/test_etcp_router.c

@@ -248,23 +248,23 @@ static int send_one_pkt(uint32_t seq, int data_len) {
 
 // ======================== Server handler ========================
 static void srv_handler(struct ETCP_CONN* conn, struct ll_entry* entry) {
-    // Restart notification: conn=NULL, len=9, format [svc_id:1][node_id:8]
-    if (!conn && entry && entry->dgram && entry->len == 9) {
+    // Restart/close notification: [svc_id][src][dst] без payload
+    if (entry && entry->dgram && entry->len == ROUTER_SVC_HDR_SIZE) {
         DEBUG_DEBUG(DEBUG_CATEGORY_DEBUG, "srv_handler: restart notification, resetting expected_seq from %u to 0", g_expected_seq);
         g_expected_seq = 0;
         queue_dgram_free(entry); queue_entry_free(entry);
         return;
     }
-    if (!entry || !entry->dgram || entry->len < 10) {
+    if (!entry || !entry->dgram || entry->len < ROUTER_SVC_PAYLOAD_OFF + 9) {
         printf("[FAIL] srv_handler: bad entry len=%zu conn=%p\n", entry ? entry->len : 0, (void*)conn);
         if (entry) { queue_dgram_free(entry); queue_entry_free(entry); }
         g_fail = 4; g_done = -1;
         return;
     }
-    uint8_t  subcmd   = entry->dgram[1];
-    uint32_t seq      = 0; memcpy(&seq, entry->dgram + 2, 4);
-    uint32_t data_len = 0; memcpy(&data_len, entry->dgram + 6, 4);
-    uint8_t* payload  = entry->dgram + 10;
+    uint8_t  subcmd   = entry->dgram[ROUTER_SVC_PAYLOAD_OFF];
+    uint32_t seq      = 0; memcpy(&seq, entry->dgram + ROUTER_SVC_PAYLOAD_OFF + 1, 4);
+    uint32_t data_len = 0; memcpy(&data_len, entry->dgram + ROUTER_SVC_PAYLOAD_OFF + 5, 4);
+    uint8_t* payload  = entry->dgram + ROUTER_SVC_PAYLOAD_OFF + 9;
 
     if (subcmd != 0x01) {
         printf("[FAIL] srv_handler: unexpected subcmd=%u seq=%u\n", subcmd, seq);
@@ -325,9 +325,9 @@ static void srv_handler(struct ETCP_CONN* conn, struct ll_entry* entry) {
 static int loop_rcvd = 0, loop_ok = 0;
 static void loop_handler(struct ETCP_CONN* conn, struct ll_entry* entry) {
     (void)conn;
-    if (entry && entry->dgram && entry->len >= 6) {
+    if (entry && entry->dgram && entry->len >= ROUTER_SVC_HDR_SIZE + 3) {
         loop_rcvd++;
-        if (entry->dgram[1] == 0xAA && entry->dgram[2] == 0xBB && entry->dgram[3] == 0xCC) loop_ok = 1;
+        if (entry->dgram[ROUTER_SVC_PAYLOAD_OFF] == 0xAA && entry->dgram[ROUTER_SVC_PAYLOAD_OFF + 1] == 0xBB && entry->dgram[ROUTER_SVC_PAYLOAD_OFF + 2] == 0xCC) loop_ok = 1;
     }
     if (entry) { queue_dgram_free(entry); queue_entry_free(entry); }
 }

tests/test_etcp_router_reconnect.c

@@ -128,14 +128,14 @@ static void cleanup(void) { test_unlink(a_conf); test_unlink(b_conf); test_unlin
 
 static void recv_handler(struct ETCP_CONN* conn, struct ll_entry* entry) {
     if (!entry || !entry->dgram) { fprintf(stderr, "RECV: null entry\n"); g_test_ok=-1; g_fail_code=10; return; }
-    if (entry->len == 9) { queue_dgram_free(entry); queue_entry_free(entry); return; }
-    if (entry->len < 7) { fprintf(stderr, "RECV: short entry len=%u\n", (unsigned)entry->len); g_test_ok=-1; g_fail_code=10; queue_dgram_free(entry); queue_entry_free(entry); return; }
-    uint32_t seq=0; memcpy(&seq,entry->dgram+1,4);
-    uint16_t sz=0;   memcpy(&sz, entry->dgram+5,2);
-    if (entry->len != (size_t)(7+sz)) { fprintf(stderr, "FAIL: size mismatch seq=%u\n", seq); g_test_ok=-1; g_fail_code=11; queue_dgram_free(entry); queue_entry_free(entry); return; }
+    if (entry->len == ROUTER_SVC_HDR_SIZE) { queue_dgram_free(entry); queue_entry_free(entry); return; }
+    if (entry->len < ROUTER_SVC_PAYLOAD_OFF + 6) { fprintf(stderr, "RECV: short entry len=%u\n", (unsigned)entry->len); g_test_ok=-1; g_fail_code=10; queue_dgram_free(entry); queue_entry_free(entry); return; }
+    uint32_t seq=0; memcpy(&seq,entry->dgram+ROUTER_SVC_PAYLOAD_OFF,4);
+    uint16_t sz=0;   memcpy(&sz, entry->dgram+ROUTER_SVC_PAYLOAD_OFF+4,2);
+    if (entry->len != (size_t)(ROUTER_SVC_PAYLOAD_OFF+6+sz)) { fprintf(stderr, "FAIL: size mismatch seq=%u\n", seq); g_test_ok=-1; g_fail_code=11; queue_dgram_free(entry); queue_entry_free(entry); return; }
     if (seq != g_expected_seq) { fprintf(stderr, "FAIL: seq broken seq=%u expected=%u\n", seq, g_expected_seq); g_test_ok=-1; g_fail_code=12; queue_dgram_free(entry); queue_entry_free(entry); return; }
     uint8_t exp[MAX_PAYLOAD]; gen_payload(seq, exp, sz);
-    if (memcmp(entry->dgram+7, exp, sz) != 0) { fprintf(stderr, "FAIL: corrupt seq=%u\n", seq); g_test_ok=-1; g_fail_code=13; queue_dgram_free(entry); queue_entry_free(entry); return; }
+    if (memcmp(entry->dgram+ROUTER_SVC_PAYLOAD_OFF+6, exp, sz) != 0) { fprintf(stderr, "FAIL: corrupt seq=%u\n", seq); g_test_ok=-1; g_fail_code=13; queue_dgram_free(entry); queue_entry_free(entry); return; }
     g_expected_seq++; g_rcvd_total++;
     queue_dgram_free(entry); queue_entry_free(entry);
 }

tests/test_etcp_router_unit.c

@@ -38,18 +38,18 @@ static int g_notify_count = 0;
 
 static void test_handler(struct ETCP_CONN* conn, struct ll_entry* entry) {
     (void)conn;
-    if (!entry || !entry->dgram || entry->len < 2) {
+    if (!entry || !entry->dgram || entry->len < ROUTER_SVC_HDR_SIZE) {
         g_notify_count++;
         if (entry) { queue_dgram_free(entry); queue_entry_free(entry); }
         return;
     }
-    // close/restart: len==9 (svc_id + node_id), conn==NULL
-    if (entry->len == 9) {
+    // close/restart: [svc_id][src][dst] без payload
+    if (entry->len == ROUTER_SVC_HDR_SIZE) {
         g_notify_count++;
         queue_dgram_free(entry); queue_entry_free(entry);
         return;
     }
-    if (entry->dgram[1] != rx.marker) { rx.errors++; } else { rx.delivered++; rx.last_seq = rx.expected_seq; rx.expected_seq++; }
+    if (entry->dgram[ROUTER_SVC_PAYLOAD_OFF] != rx.marker) { rx.errors++; } else { rx.delivered++; rx.last_seq = rx.expected_seq; rx.expected_seq++; }
     queue_dgram_free(entry); queue_entry_free(entry);
 }
 

tests/test_icmp_proxy.c

@@ -82,16 +82,16 @@ static void* g_to_id = NULL;
 
 static void cli_recv_cb(struct ETCP_CONN* conn, struct ll_entry* entry) {
     (void)conn;
-    if (!entry || !entry->dgram || entry->len < ICMP_PROXY_HDR_SIZE + 1) {
+    if (!entry || !entry->dgram || entry->len < ICMP_PROXY_RECV_HDR_SIZE + 1) {
         if (entry) { queue_dgram_free(entry); queue_entry_free(entry); } return;
     }
-    if (entry->dgram[1] == ICMP_PROXY_SUBCMD_REPLY) {
+    if (entry->dgram[ROUTER_SVC_PAYLOAD_OFF] == ICMP_PROXY_SUBCMD_REPLY) {
         uint16_t rid, rseq;
-        memcpy(&rid,  entry->dgram + 18, 2);
-        memcpy(&rseq, entry->dgram + 20, 2);
+        memcpy(&rid,  entry->dgram + ROUTER_SVC_PAYLOAD_OFF + 9, 2);
+        memcpy(&rseq, entry->dgram + ROUTER_SVC_PAYLOAD_OFF + 11, 2);
         if (rid == test_echo_id && rseq == test_echo_seq) {
-            size_t payload_len = entry->len - ICMP_PROXY_HDR_SIZE;
-            uint8_t* payload = entry->dgram + ICMP_PROXY_HDR_SIZE;
+            size_t payload_len = entry->len - ICMP_PROXY_RECV_HDR_SIZE;
+            uint8_t* payload = entry->dgram + ICMP_PROXY_RECV_HDR_SIZE;
             if (payload_len == ICMP_PAYLOAD_SIZE && memcmp(payload, send_buf, ICMP_PAYLOAD_SIZE) == 0) {
                 reply_rcvd = 1; g_done = 1; g_ok = 1;
             } else {

tests/test_nat_transport.c

@@ -35,7 +35,7 @@
 #define TEST_TIMEOUT_MS 15000
 static uint64_t g_provider_node_id = 0;
 static uint64_t g_client_node_id = 0;
-#define NAT_SVC_HDR_SIZE 9  // svc_id(1) + src_node_id(8)
+#define NAT_SVC_HDR_SIZE 1  // send: svc_id(1) + ip_data (src/dst добавляет роутер)
 
 static struct UTUN_INSTANCE* inst_provider = NULL;
 static struct UTUN_INSTANCE* inst_client = NULL;
@@ -293,14 +293,13 @@ static int test_provider_egress(void) {
     }
     DEBUG_INFO(DEBUG_CATEGORY_NAT, "Client conn peer_node_id=0x%016llx", (unsigned long long)client_conn->peer_node_id);
 
-    // Build ETCP_RT_ID_NAT packet via etcp_route_send (new format: svc_id + src_node_id + ip_data)
+    // Build ETCP_RT_ID_NAT packet via etcp_route_send (src/dst node_id добавляет роутер)
     size_t ip_len;
     uint8_t* raw_ip = build_udp_pkt(0x0A0000FE, 40000, 0x08080808, 53, &ip_len);
     size_t total = NAT_SVC_HDR_SIZE + ip_len;
     uint8_t* dgram = u_malloc(total);
     dgram[0] = ETCP_RT_ID_NAT;
-    memcpy(dgram + 1, &inst_client->nat_tr.self_node_id, 8);
-    memcpy(dgram + 9, raw_ip, ip_len);
+    memcpy(dgram + 1, raw_ip, ip_len);
     free(raw_ip);
 
     struct ll_entry* entry = queue_entry_new(0);
@@ -469,8 +468,7 @@ static int test_full_roundtrip(void) {
     size_t total = NAT_SVC_HDR_SIZE + ip_len;
     uint8_t* dgram = u_malloc(total);
     dgram[0] = ETCP_RT_ID_NAT;
-    memcpy(dgram + 1, &inst_client->nat_tr.self_node_id, 8);
-    memcpy(dgram + 9, raw_ip, ip_len);
+    memcpy(dgram + 1, raw_ip, ip_len);
     free(raw_ip);
 
     struct ll_entry* entry = queue_entry_new(0);

tests/test_tcp_io.c

@@ -307,6 +307,52 @@ static void test_error_callback(void) {
     TEST_PASS();
 }
 
+static void test_connect_timeout(void) {
+    TEST_START("Connect timeout on black hole (200ms)");
+#ifdef _WIN32
+    TEST_PASS();
+    return;
+#else
+    uasync_t* ua = uasync_create();
+    ASSERT_TRUE(ua != NULL, "uasync_create failed");
+    reset_counters();
+
+    int fd = socket(AF_INET, SOCK_STREAM, 0);
+    ASSERT_TRUE(fd >= 0, "socket failed");
+    fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) | O_NONBLOCK);
+
+    struct sockaddr_in addr;
+    memset(&addr, 0, sizeof(addr));
+    addr.sin_family = AF_INET;
+    addr.sin_port = htons(81);
+    addr.sin_addr.s_addr = htonl(0xC0000201);  // 192.0.2.1 (TEST-NET-1, RFC 5737) — чёрная дыра
+
+    int ret = connect(fd, (struct sockaddr*)&addr, sizeof(addr));
+    ASSERT_TRUE(ret < 0 && errno == EINPROGRESS, "connect should return EINPROGRESS");
+
+    struct tcp_conn* tc = tcp_conn_create(ua, fd, 1500, 8192, 32, 8, 0, on_fin, on_error, NULL);
+    ASSERT_TRUE(tc != NULL, "tcp_conn_create failed");
+    ASSERT_EQ(tc->connected, 0, "should not be connected");
+
+    tcp_conn_set_connect_timeout(tc, 200);
+
+    // Крутим цикл (1 мс × 500) пока таймаут не сработает
+    int iterations = 0;
+    while (g_error_count == 0 && iterations < 500) {
+        uasync_poll(ua, 10);
+        iterations++;
+    }
+    ASSERT_EQ(g_error_count, 1, "on_error not called on connect timeout");
+    ASSERT_EQ(g_last_error, ETIMEDOUT, "on_error should report ETIMEDOUT");
+    ASSERT_EQ(tc->connected, 0, "connection should still be not connected");
+    ASSERT_EQ(tc->error, 1, "tc->error should be set");
+
+    tcp_conn_destroy(tc);
+    uasync_destroy(ua, 0);
+    TEST_PASS();
+#endif
+}
+
 // ====================================================================
 // FIN / Close через очередь — новые тесты
 // ====================================================================
@@ -552,6 +598,7 @@ int main(void) {
     test_high_water_pause();
     test_connect_detection();
     test_error_callback();
+    test_connect_timeout();
     test_push_fin();
     test_push_close();
     test_fin_data_ordering();

tests/test_udp_proxy.c

@@ -92,13 +92,12 @@ static void udp_echo_cb(socket_t sock, void* arg) {
 
 static void cli_recv_cb(struct ETCP_CONN* conn, struct ll_entry* entry) {
     (void)conn;
-    if (!entry || !entry->dgram || entry->len < UDP_PROXY_HDR_SIZE + 1) {
+    if (!entry || !entry->dgram || entry->len < UDP_PROXY_RECV_HDR_SIZE + 1) {
         if (entry) { queue_dgram_free(entry); queue_entry_free(entry); } return;
     }
-    // svc_id(1) + subcmd(1) + sender_node_id(8) + src_ip(4) + src_port(2) + dst_ip(4) + dst_port(2) + payload
-    size_t payload_len = entry->len - UDP_PROXY_HDR_SIZE;
-    if (entry->dgram[1] == UDP_PROXY_SUBCMD_DATA) {
-        uint8_t* payload = entry->dgram + UDP_PROXY_HDR_SIZE;
+    size_t payload_len = entry->len - UDP_PROXY_RECV_HDR_SIZE;
+    if (entry->dgram[ROUTER_SVC_PAYLOAD_OFF] == UDP_PROXY_SUBCMD_DATA) {
+        uint8_t* payload = entry->dgram + UDP_PROXY_RECV_HDR_SIZE;
         if (payload_len == PAYLOAD_SIZE && memcmp(payload, send_buf, PAYLOAD_SIZE) == 0) {
             reply_rcvd = 1; g_done = 1; g_ok = 1;
         } else {