add metrics to monitor

src/control_server.c

@@ -753,6 +753,12 @@ static void send_metrics(struct control_server* server, struct control_client* c
     rsp->etcp.retrans_timer_active = (conn->retrans_timer != NULL) ? 1 : 0;
     rsp->etcp.ack_resp_timer_active = (conn->ack_resp_timer != NULL) ? 1 : 0;
     
+    /* Connection IDs */
+    rsp->etcp.next_tx_id = conn->next_tx_id;
+    rsp->etcp.last_rx_id = conn->last_rx_id;
+    rsp->etcp.last_delivered_id = conn->last_delivered_id;
+    rsp->etcp.rx_ack_till = conn->rx_ack_till;
+    
     /* Fill TUN metrics */
     if (instance->tun) {
         rsp->tun.bytes_read = instance->tun->bytes_read;
@@ -784,6 +790,8 @@ static void send_metrics(struct control_server* server, struct control_client* c
         link_info[i].init_timer_active = (link->init_timer != NULL) ? 1 : 0;
         link_info[i].keepalive_timer_active = (link->keepalive_timer != NULL) ? 1 : 0;
         link_info[i].shaper_timer_active = (link->shaper_timer != NULL) ? 1 : 0;
+        link_info[i].keepalive_sent = (uint32_t)link->keepalive_sent_count;
+        link_info[i].keepalive_recv = (uint32_t)link->keepalive_recv_count;
         link = link->next;
     }
     

src/etcp.h

@@ -103,7 +103,7 @@ struct ETCP_CONN {
     uint32_t last_rx_id;           // Last received ID
     uint32_t last_delivered_id;    // Last delivered to output_queue
 
-    uint32_t rx_ack_till;// из ack пакета - по какой пакет получено и собрано на уданенной стороне
+    uint32_t rx_ack_till;// из ack пакета - по какой пакет получено и собрано на удаленной стороне
 
     // Metrics (RTT, jitter, etc.)
     // uint16_t retrans_delay;       // Not used

src/etcp_connections.c

@@ -140,6 +140,8 @@ static void etcp_link_send_keepalive(struct ETCP_LINK* link) {
     DEBUG_DEBUG(DEBUG_CATEGORY_CONNECTION, "[%s] Sending keepalive on link %p (local_id=%d)",
                 link->etcp->log_name, link, link->local_link_id);
 
+    link->keepalive_sent_count++;
+    
     etcp_encrypt_send(dgram);
     u_free(dgram);
 }
@@ -572,6 +574,8 @@ struct ETCP_LINK* etcp_link_new(struct ETCP_CONN* etcp, struct ETCP_SOCKET* conn
         link->keepalive_timeout = 2000;  // Default 2 seconds
         link->keepalive_interval = 200;  // Default 0.2 s
     }
+    link->keepalive_sent_count = 0;
+    link->keepalive_recv_count = 0;
 
     // Выделяем свободный local_link_id
     int free_id = etcp_find_free_local_link_id(etcp);
@@ -1006,7 +1010,12 @@ process_decrypted:
         DEBUG_INFO(DEBUG_CATEGORY_CONNECTION, "[%s] Link %p (local_id=%d) status changed to UP - packet received",
                    link->etcp->log_name, link, link->local_link_id);
     }
-
+    
+    // Count received keepalive packets (empty packets with no payload)
+    if (pkt->data_len == 0) {
+        link->keepalive_recv_count++;
+    }
+    
     // Cancel all init timers - link is alive, no need for recovery
     etcp_cancel_all_init_timers(link->etcp);
 

src/etcp_connections.h

@@ -111,6 +111,8 @@ struct ETCP_LINK {
     void* keepalive_timer;           // Таймер для отправки keepalive пакетов
     uint32_t keepalive_timeout;      // таймаут (ms)
     uint8_t pkt_sent_since_keepalive; // Флаг: был ли отправлен пакет с последнего keepalive тика
+    uint32_t keepalive_sent_count;  // Счётчик отправленных keepalive
+    uint32_t keepalive_recv_count;  // Счётчик полученных keepalive
 };
 
 // INITIALIZATION (создаёт listen-сокеты и подключения из конфига)