Fix ETCP timestamp overflow bug and enable epoll for Linux

lib/u_async.c

@@ -399,8 +399,7 @@ void* uasync_add_socket(struct UASYNC* ua, int fd, socket_callback_t read_cbk, s
         ev.events = 0;
         if (read_cbk) ev.events |= EPOLLIN;
         if (write_cbk) ev.events |= EPOLLOUT;
-        // Use edge-triggered mode for better performance
+        // Use level-triggered mode (default) for compatibility with UDP sockets
-        ev.events |= EPOLLET;
         ev.data.ptr = &ua->sockets->sockets[index];
         
         if (epoll_ctl(ua->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0) {

src/etcp.c

@@ -81,6 +81,7 @@ struct ETCP_CONN* etcp_connection_create(struct UTUN_INSTANCE* instance) {
     etcp->ack_q = queue_new(instance->ua, 0);
     etcp->inflight_pool = memory_pool_init(sizeof(struct INFLIGHT_PACKET));
     etcp->io_pool = memory_pool_init(sizeof(struct ETCP_FRAGMENT));
+    etcp->optimal_inflight=10000;
     
     if (!etcp->input_queue || !etcp->output_queue || !etcp->input_send_q || !etcp->recv_q || !etcp->ack_q ||
         !etcp->input_wait_ack || !etcp->inflight_pool || !etcp->io_pool) {
@@ -320,9 +321,11 @@ static void input_queue_try_resume(struct ETCP_CONN* etcp) {
     size_t send_q_bytes = queue_total_bytes(etcp->input_send_q);
     size_t total_bytes = wait_ack_bytes + send_q_bytes;
     
-    if (total_bytes < etcp->optimal_inflight) {
+    if (total_bytes <= etcp->optimal_inflight) {
+        DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] resume callbacks: inflight_bytes=%d, input_len=%d", etcp->log_name, total_bytes, etcp->input_queue->total_bytes);
         queue_resume_callback(etcp->input_send_q);// вызвать лишний раз resume не страшно.
-        DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] resumed input_send_q callback", etcp->log_name);
+//etcp_stats(etcp);
+        if (queue_entry_count(etcp->input_send_q) == 0) queue_resume_callback(etcp->input_queue);// и только когда больше нечего отправлять - забираем новый пакет
     }
 }
 
@@ -406,6 +409,7 @@ static void input_queue_cb(struct ll_queue* q, void* arg) {
     
     // Add to send queue
     if (queue_data_put(etcp->input_send_q, (struct ll_entry*)p, p->seq) != 0) {
+        DEBUG_ERROR(DEBUG_CATEGORY_ETCP, "[%s] failed to add packet seq=%u to input_send_q", etcp->log_name, p->seq);
         memory_pool_free(etcp->inflight_pool, p);
         queue_entry_free((struct ll_entry*)in_pkt);
         DEBUG_TRACE(DEBUG_CATEGORY_ETCP, "[%s] EXIT (queue put failed)", etcp->log_name);
@@ -415,7 +419,7 @@ static void input_queue_cb(struct ll_queue* q, void* arg) {
 
     etcp_conn_process_send_queue(etcp);// сразу обработаем этот пакет
 //    input_queue_try_resume(etcp);
-    queue_resume_callback(etcp->input_queue);
+    DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] nextloop, input_queue size=%d ", etcp->log_name, q->count);
 }
 
 
@@ -440,6 +444,23 @@ static void ack_timeout_check(void* arg) {
     struct ll_entry* current;
     while (current = etcp->input_wait_ack->head) {
         struct INFLIGHT_PACKET* pkt = (struct INFLIGHT_PACKET*)current;
+        
+        // Check for invalid timestamp
+        if (pkt->last_timestamp == 0) {
+            DEBUG_ERROR(DEBUG_CATEGORY_ETCP, "[%s] ack_timeout_check: packet seq=%u has last_timestamp=0, not sent yet!",
+                       etcp->log_name, pkt->seq);
+            // Schedule timer to check again later
+            etcp->retrans_timer = uasync_set_timeout(etcp->instance->ua, timeout, etcp, ack_timeout_check);
+            return;
+        }
+        
+        if (pkt->last_timestamp > now) {
+            DEBUG_ERROR(DEBUG_CATEGORY_ETCP, "[%s] ack_timeout_check: packet seq=%u has last_timestamp=%llu > now=%llu, clock went backwards!",
+                       etcp->log_name, pkt->seq, (unsigned long long)pkt->last_timestamp, (unsigned long long)now);
+            // Fix the timestamp to prevent overflow
+            pkt->last_timestamp = now;
+        }
+        
         uint64_t elapsed = now - pkt->last_timestamp;
         if (elapsed > timeout) {
         DEBUG_WARN(DEBUG_CATEGORY_ETCP, "[%s] ack_timeout_check: timeout for seq=%u, elapsed=%llu, timeout=%llu, send_count=%u. Moving: wait_ack -> send_q",
@@ -512,7 +533,7 @@ struct ETCP_DGRAM* etcp_request_pkt(struct ETCP_CONN* etcp) {
     size_t ack_q_size = queue_entry_count(etcp->ack_q);
 
     if (!inf_pkt && ack_q_size == 0) {
-        DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] no data/ack to send", etcp->log_name);
+//        DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] no data/ack to send", etcp->log_name);
         return NULL;
     }
 
@@ -611,8 +632,8 @@ static void ack_response_timer_cb(void* arg) {// проверяем неотпр
 
 void etcp_output_try_assembly(struct ETCP_CONN* etcp) {
     // пробуем собрать выходную очередь из фрагментов
-    DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] etcp=%p, last_delivered_id=%u, recv_q_count=%d",
+//    DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] etcp=%p, last_delivered_id=%u, recv_q_count=%d",
-                etcp->log_name, etcp, etcp->last_delivered_id, queue_entry_count(etcp->recv_q));
+//                etcp->log_name, etcp, etcp->last_delivered_id, queue_entry_count(etcp->recv_q));
     
     uint32_t next_expected_id = etcp->last_delivered_id + 1;
     int delivered_count = 0;
@@ -623,12 +644,12 @@ void etcp_output_try_assembly(struct ETCP_CONN* etcp) {
         struct ETCP_FRAGMENT* rx_pkt = (struct ETCP_FRAGMENT*)queue_find_data_by_id(etcp->recv_q, next_expected_id);
         if (!rx_pkt) {
             // No more contiguous packets found
-            DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] no packet found for id=%u, stopping", etcp->log_name, next_expected_id);
+//            DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] no packet found for id=%u, stopping", etcp->log_name, next_expected_id);
             break;
         }
 
-        DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] assembling packet id=%u (len=%u)", etcp->log_name,
+//        DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] assembling packet id=%u (len=%u)", etcp->log_name,
-                    rx_pkt->seq, rx_pkt->ll.len);
+//                    rx_pkt->seq, rx_pkt->ll.len);
 
         // Simply move ETCP_FRAGMENT from recv_q to output_queue - no data copying needed
         // Remove from recv_q first
@@ -661,7 +682,7 @@ void etcp_output_try_assembly(struct ETCP_CONN* etcp) {
 void etcp_ack_recv(struct ETCP_CONN* etcp, uint32_t seq, uint16_t ts, uint16_t dts) {
     if (!etcp) return;
     
-    DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] processing ACK for seq=%u, ts=%u, dts=%u", etcp->log_name, seq, ts, dts);
+//    DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] processing ACK for seq=%u, ts=%u, dts=%u", etcp->log_name, seq, ts, dts);
     
     // Find the acknowledged packet in the wait_ack queue
     struct INFLIGHT_PACKET* acked_pkt = (struct INFLIGHT_PACKET*)queue_find_data_by_id(etcp->input_wait_ack, seq);
@@ -703,8 +724,8 @@ void etcp_ack_recv(struct ETCP_CONN* etcp, uint32_t seq, uint16_t ts, uint16_t d
         }
         etcp->jitter = rtt_max - rtt_min;
         
-        DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] RTT updated - last=%u, avg_10=%u, avg_100=%u, jitter=%u",
+//        DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] RTT updated - last=%u, avg_10=%u, avg_100=%u, jitter=%u",
-                    etcp->log_name, rtt, etcp->rtt_avg_10, etcp->rtt_avg_100, etcp->jitter);
+//                    etcp->log_name, rtt, etcp->rtt_avg_10, etcp->rtt_avg_100, etcp->jitter);
     }
 
     // Update connection statistics
@@ -712,7 +733,7 @@ void etcp_ack_recv(struct ETCP_CONN* etcp, uint32_t seq, uint16_t ts, uint16_t d
     etcp->bytes_sent_total += acked_pkt->ll.len;
     etcp->ack_packets_count++;
 
-    DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] removed packet seq=%u from wait_ack, unacked_bytes now %u", etcp->log_name, seq, etcp->unacked_bytes);
+    DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] removed packet seq=%u from wait_ack, unacked_bytes now %u total acked=%u", etcp->log_name, seq, etcp->unacked_bytes, etcp->ack_packets_count);
 
     if (acked_pkt->ll.dgram) {
         memory_pool_free(etcp->instance->data_pool, acked_pkt->ll.dgram);
@@ -722,7 +743,7 @@ void etcp_ack_recv(struct ETCP_CONN* etcp, uint32_t seq, uint16_t ts, uint16_t d
     // Try to resume sending more packets if window space opened up
     input_queue_try_resume(etcp);
     
-    DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] completed for seq=%u", etcp->log_name, seq);
+//    DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] completed for seq=%u", etcp->log_name, seq);
 }
 
 
@@ -778,7 +799,16 @@ void etcp_conn_input(struct ETCP_DGRAM* pkt) {
                         DEBUG_DEBUG(DEBUG_CATEGORY_ETCP, "[%s] adding packet seq=%u to recv_q (last_delivered_id=%u)", etcp->log_name, seq, etcp->last_delivered_id);
                         // отправляем пакет в очередь на сборку
                         uint8_t* payload_data = memory_pool_alloc(etcp->instance->data_pool);
+                        if (!payload_data) {
+                            DEBUG_ERROR(DEBUG_CATEGORY_ETCP, "[%s] failed to allocate payload_data from data_pool", etcp->log_name);
+                            break;
+                        }
                         struct ETCP_FRAGMENT* rx_pkt = (struct ETCP_FRAGMENT*)queue_entry_new_from_pool(etcp->io_pool);
+                        if (!rx_pkt) {
+                            DEBUG_ERROR(DEBUG_CATEGORY_ETCP, "[%s] failed to allocate rx_pkt from io_pool", etcp->log_name);
+                            memory_pool_free(etcp->instance->data_pool, payload_data);
+                            break;
+                        }
                         rx_pkt->seq=seq;
                         rx_pkt->timestamp=pkt->timestamp;
                         rx_pkt->ll.dgram=payload_data;