Make tcp active open data structures thread safe
[vpp.git] / src / vnet / tcp / tcp_output.c
index 47c94e6..1ecb6ce 100644 (file)
@@ -19,7 +19,7 @@
 vlib_node_registration_t tcp4_output_node;
 vlib_node_registration_t tcp6_output_node;
 
-typedef enum _tcp_output_nect
+typedef enum _tcp_output_next
 {
   TCP_OUTPUT_NEXT_DROP,
   TCP_OUTPUT_NEXT_IP_LOOKUP,
@@ -75,12 +75,34 @@ tcp_window_compute_scale (u32 available_space)
 }
 
 /**
- * TCP's IW as recommended by RFC6928
+ * Update max segment size we're able to process.
+ *
+ * The value is constrained by our interface's MTU and IP options. It is
+ * also what we advertise to our peer.
+ */
+void
+tcp_update_rcv_mss (tcp_connection_t * tc)
+{
+  /* TODO find our iface MTU */
+  tc->mss = dummy_mtu;
+}
+
+/**
+ * TCP's initial window
  */
 always_inline u32
 tcp_initial_wnd_unscaled (tcp_connection_t * tc)
 {
-  return TCP_IW_N_SEGMENTS * tc->mss;
+  /* RFC 6928 recommends the value lower. However at the time our connections
+   * are initialized, fifos may not be allocated. Therefore, advertise the
+   * smallest possible unscaled window size and update once fifos are
+   * assigned to the session.
+   */
+  /*
+     tcp_update_rcv_mss (tc);
+     TCP_IW_N_SEGMENTS * tc->mss;
+   */
+  return TCP_MIN_RX_FIFO_SIZE;
 }
 
 /**
@@ -372,19 +394,6 @@ tcp_make_options (tcp_connection_t * tc, tcp_options_t * opts,
     }
 }
 
-/**
- * Update max segment size we're able to process.
- *
- * The value is constrained by our interface's MTU and IP options. It is
- * also what we advertise to our peer.
- */
-void
-tcp_update_rcv_mss (tcp_connection_t * tc)
-{
-  /* TODO find our iface MTU */
-  tc->mss = dummy_mtu;
-}
-
 /**
  * Update snd_mss to reflect the effective segment size that we can send
  * by taking into account all TCP options, including SACKs
@@ -430,16 +439,16 @@ tcp_init_mss (tcp_connection_t * tc)
 #define tcp_get_free_buffer_index(tm, bidx)                             \
 do {                                                                    \
   u32 *my_tx_buffers, n_free_buffers;                                   \
-  u32 thread_index = vlib_get_thread_index();                                  \
-  my_tx_buffers = tm->tx_buffers[thread_index];                            \
+  u32 thread_index = vlib_get_thread_index();                           \
+  my_tx_buffers = tm->tx_buffers[thread_index];                         \
   if (PREDICT_FALSE(vec_len (my_tx_buffers) == 0))                      \
     {                                                                   \
       n_free_buffers = 32;      /* TODO config or macro */              \
       vec_validate (my_tx_buffers, n_free_buffers - 1);                 \
       _vec_len(my_tx_buffers) = vlib_buffer_alloc_from_free_list (      \
-          tm->vlib_main, my_tx_buffers, n_free_buffers,                 \
+       vlib_get_main(), my_tx_buffers, n_free_buffers,                  \
           VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);                         \
-      tm->tx_buffers[thread_index] = my_tx_buffers;                        \
+      tm->tx_buffers[thread_index] = my_tx_buffers;                     \
     }                                                                   \
   /* buffer shortage */                                                 \
   if (PREDICT_FALSE (vec_len (my_tx_buffers) == 0))                     \
@@ -448,12 +457,12 @@ do {                                                                    \
   _vec_len (my_tx_buffers) -= 1;                                        \
 } while (0)
 
-#define tcp_return_buffer(tm)                                          \
-do {                                                                   \
-  u32 *my_tx_buffers;                                                  \
-  u32 thread_index = vlib_get_thread_index();                                  \
-  my_tx_buffers = tm->tx_buffers[thread_index];                                \
-  _vec_len (my_tx_buffers) +=1;                                                \
+#define tcp_return_buffer(tm)                   \
+do {                                            \
+  u32 *my_tx_buffers;                           \
+  u32 thread_index = vlib_get_thread_index();   \
+  my_tx_buffers = tm->tx_buffers[thread_index]; \
+  _vec_len (my_tx_buffers) +=1;                 \
 } while (0)
 
 always_inline void
@@ -576,6 +585,7 @@ tcp_make_synack (tcp_connection_t * tc, vlib_buffer_t * b)
 
   /* Init retransmit timer */
   tcp_retransmit_timer_set (tc);
+  TCP_EVT_DBG (TCP_EVT_SYNACK_SENT, tc);
 }
 
 always_inline void
@@ -585,7 +595,7 @@ tcp_enqueue_to_ip_lookup (vlib_main_t * vm, vlib_buffer_t * b, u32 bi,
   u32 *to_next, next_index;
   vlib_frame_t *f;
 
-  b->flags |= VNET_BUFFER_LOCALLY_ORIGINATED;
+  b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
   b->error = 0;
 
   /* Default FIB for now */
@@ -684,7 +694,7 @@ tcp_make_reset_in_place (vlib_main_t * vm, vlib_buffer_t * b0,
  *  Send reset without reusing existing buffer
  */
 void
-tcp_send_reset (vlib_buffer_t * pkt, u8 is_ip4)
+tcp_send_reset (tcp_connection_t * tc, vlib_buffer_t * pkt, u8 is_ip4)
 {
   vlib_buffer_t *b;
   u32 bi;
@@ -720,7 +730,7 @@ tcp_send_reset (vlib_buffer_t * pkt, u8 is_ip4)
     {
       flags = TCP_FLAG_RST;
       seq = pkt_th->ack_number;
-      ack = 0;
+      ack = (tc && tc->state >= TCP_STATE_SYN_RCVD) ? tc->rcv_nxt : 0;
     }
   else
     {
@@ -754,29 +764,29 @@ tcp_send_reset (vlib_buffer_t * pkt, u8 is_ip4)
     }
 
   tcp_enqueue_to_ip_lookup (vm, b, bi, is_ip4);
+  TCP_EVT_DBG (TCP_EVT_RST_SENT, tc);
 }
 
 void
 tcp_push_ip_hdr (tcp_main_t * tm, tcp_connection_t * tc, vlib_buffer_t * b)
 {
   tcp_header_t *th = vlib_buffer_get_current (b);
-
+  vlib_main_t *vm = vlib_get_main ();
   if (tc->c_is_ip4)
     {
       ip4_header_t *ih;
-      ih = vlib_buffer_push_ip4 (tm->vlib_main, b, &tc->c_lcl_ip4,
+      ih = vlib_buffer_push_ip4 (vm, b, &tc->c_lcl_ip4,
                                 &tc->c_rmt_ip4, IP_PROTOCOL_TCP);
-      th->checksum = ip4_tcp_udp_compute_checksum (tm->vlib_main, b, ih);
+      th->checksum = ip4_tcp_udp_compute_checksum (vm, b, ih);
     }
   else
     {
       ip6_header_t *ih;
       int bogus = ~0;
 
-      ih = vlib_buffer_push_ip6 (tm->vlib_main, b, &tc->c_lcl_ip6,
+      ih = vlib_buffer_push_ip6 (vm, b, &tc->c_lcl_ip6,
                                 &tc->c_rmt_ip6, IP_PROTOCOL_TCP);
-      th->checksum = ip6_tcp_udp_icmp_compute_checksum (tm->vlib_main, b, ih,
-                                                       &bogus);
+      th->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ih, &bogus);
       ASSERT (!bogus);
     }
 }
@@ -840,6 +850,7 @@ tcp_send_syn (tcp_connection_t * tc)
 
   tcp_push_ip_hdr (tm, tc, b);
   tcp_enqueue_to_ip_lookup (vm, b, bi, tc->c_is_ip4);
+  TCP_EVT_DBG (TCP_EVT_SYN_SENT, tc);
 }
 
 always_inline void
@@ -848,12 +859,19 @@ tcp_enqueue_to_output (vlib_main_t * vm, vlib_buffer_t * b, u32 bi, u8 is_ip4)
   u32 *to_next, next_index;
   vlib_frame_t *f;
 
-  b->flags |= VNET_BUFFER_LOCALLY_ORIGINATED;
+  b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
   b->error = 0;
 
   /* Decide where to send the packet */
   next_index = is_ip4 ? tcp4_output_node.index : tcp6_output_node.index;
 
+  /* Initialize the trajectory trace, if configured */
+  if (VLIB_BUFFER_TRACE_TRAJECTORY > 0)
+    {
+      b->pre_data[0] = 1;
+      b->pre_data[1] = next_index;
+    }
+
   /* Enqueue the packet */
   f = vlib_get_frame_to_node (vm, next_index);
   to_next = vlib_frame_vector_args (f);
@@ -1052,6 +1070,7 @@ tcp_rtx_timeout_cc (tcp_connection_t * tc)
   tc->ssthresh = clib_max (tcp_flight_size (tc) / 2, 2 * tc->snd_mss);
   tc->cwnd = tcp_loss_wnd (tc);
   tc->snd_congestion = tc->snd_una_max;
+
   tcp_recovery_on (tc);
 }
 
@@ -1068,15 +1087,14 @@ tcp_timer_retransmit_handler_i (u32 index, u8 is_syn)
   if (is_syn)
     {
       tc = tcp_half_open_connection_get (index);
+      tc->timers[TCP_TIMER_RETRANSMIT_SYN] = TCP_TIMER_HANDLE_INVALID;
     }
   else
     {
       tc = tcp_connection_get (index, thread_index);
+      tc->timers[TCP_TIMER_RETRANSMIT] = TCP_TIMER_HANDLE_INVALID;
     }
 
-  /* Make sure timer handle is set to invalid */
-  tc->timers[TCP_TIMER_RETRANSMIT] = TCP_TIMER_HANDLE_INVALID;
-
   if (!tcp_in_recovery (tc) && tc->rto_boff > 0
       && tc->state >= TCP_STATE_ESTABLISHED)
     {
@@ -1135,17 +1153,33 @@ tcp_timer_retransmit_handler_i (u32 index, u8 is_syn)
   /* Retransmit for SYN/SYNACK */
   else if (tc->state == TCP_STATE_SYN_RCVD || tc->state == TCP_STATE_SYN_SENT)
     {
+      /* Half-open connection actually moved to established but we were
+       * waiting for syn retransmit to pop to call cleanup from the right
+       * thread. */
+      if (tc->flags & TCP_CONN_HALF_OPEN_DONE)
+       {
+         ASSERT (tc->state == TCP_STATE_SYN_SENT);
+         if (tcp_half_open_connection_cleanup (tc))
+           {
+             clib_warning ("could not remove half-open connection");
+             ASSERT (0);
+           }
+         return;
+       }
+
       /* Try without increasing RTO a number of times. If this fails,
        * start growing RTO exponentially */
       if (tc->rto_boff > TCP_RTO_SYN_RETRIES)
        tc->rto = clib_min (tc->rto << 1, TCP_RTO_MAX);
 
       vlib_buffer_make_headroom (b, MAX_HDRS_LEN);
-
       tcp_push_hdr_i (tc, b, tc->state, 1);
 
       /* Account for the SYN */
       tc->snd_nxt += 1;
+      tc->rtt_ts = 0;
+      TCP_EVT_DBG (TCP_EVT_SYN_RXT, tc,
+                  (tc->state == TCP_STATE_SYN_SENT ? 0 : 1));
     }
   else
     {
@@ -1165,8 +1199,6 @@ tcp_timer_retransmit_handler_i (u32 index, u8 is_syn)
     {
       ASSERT (tc->state == TCP_STATE_SYN_SENT);
 
-      TCP_EVT_DBG (TCP_EVT_SYN_RTX, tc);
-
       /* This goes straight to ipx_lookup */
       tcp_push_ip_hdr (tm, tc, b);
       tcp_enqueue_to_ip_lookup (vm, b, bi, tc->c_is_ip4);
@@ -1213,7 +1245,7 @@ tcp_timer_persist_handler (u32 index)
   tc->timers[TCP_TIMER_PERSIST] = TCP_TIMER_HANDLE_INVALID;
 
   /* Problem already solved or worse */
-  if (tc->state == TCP_STATE_CLOSED
+  if (tc->state == TCP_STATE_CLOSED || tc->state > TCP_STATE_ESTABLISHED
       || tc->snd_wnd > tc->snd_mss || tcp_in_recovery (tc))
     return;
 
@@ -1234,7 +1266,7 @@ tcp_timer_persist_handler (u32 index)
   /* Nothing to send */
   if (n_bytes <= 0)
     {
-      clib_warning ("persist found nothing to send");
+      // clib_warning ("persist found nothing to send");
       tcp_return_buffer (tm);
       return;
     }
@@ -1477,7 +1509,12 @@ tcp46_output_inline (vlib_main_t * vm,
              ip4_header_t *ih0;
              ih0 = vlib_buffer_push_ip4 (vm, b0, &tc0->c_lcl_ip4,
                                          &tc0->c_rmt_ip4, IP_PROTOCOL_TCP);
-             th0->checksum = ip4_tcp_udp_compute_checksum (vm, b0, ih0);
+             b0->flags |= VNET_BUFFER_F_IS_IP4 |
+               VNET_BUFFER_F_OFFLOAD_IP_CKSUM |
+               VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
+             vnet_buffer (b0)->l3_hdr_offset = (u8 *) ih0 - b0->data;
+             vnet_buffer (b0)->l4_hdr_offset = (u8 *) th0 - b0->data;
+             th0->checksum = 0;
            }
          else
            {
@@ -1486,8 +1523,13 @@ tcp46_output_inline (vlib_main_t * vm,
 
              ih0 = vlib_buffer_push_ip6 (vm, b0, &tc0->c_lcl_ip6,
                                          &tc0->c_rmt_ip6, IP_PROTOCOL_TCP);
-             th0->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b0, ih0,
-                                                                &bogus);
+
+             b0->flags |= VNET_BUFFER_F_IS_IP6 |
+               VNET_BUFFER_F_OFFLOAD_IP_CKSUM |
+               VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
+             vnet_buffer (b0)->l3_hdr_offset = (u8 *) ih0 - b0->data;
+             vnet_buffer (b0)->l4_hdr_offset = (u8 *) th0 - b0->data;
+             th0->checksum = 0;
              ASSERT (!bogus);
            }
 
@@ -1505,10 +1547,7 @@ tcp46_output_inline (vlib_main_t * vm,
 
          /* Stop DELACK timer and fix flags */
          tc0->flags &= ~(TCP_CONN_SNDACK);
-         if (tcp_timer_is_active (tc0, TCP_TIMER_DELACK))
-           {
-             tcp_timer_reset (tc0, TCP_TIMER_DELACK);
-           }
+         tcp_timer_reset (tc0, TCP_TIMER_DELACK);
 
          /* If not retransmitting
           * 1) update snd_una_max (SYN, SYNACK, FIN)
@@ -1532,12 +1571,33 @@ tcp46_output_inline (vlib_main_t * vm,
              tc0->rto_boff = 0;
            }
 
-         /* set fib index to default and lookup node */
-         /* XXX network virtualization (vrf/vni) */
+#if 0
+         /* Make sure we haven't lost route to our peer */
+         if (PREDICT_FALSE (tc0->last_fib_check
+                            < tc0->snd_opts.tsval + TCP_FIB_RECHECK_PERIOD))
+           {
+             if (PREDICT_TRUE
+                 (tc0->c_rmt_fei == tcp_lookup_rmt_in_fib (tc0)))
+               {
+                 tc0->last_fib_check = tc0->snd_opts.tsval;
+               }
+             else
+               {
+                 clib_warning ("lost connection to peer");
+                 tcp_connection_reset (tc0);
+                 goto done;
+               }
+           }
+
+         /* Use pre-computed dpo to set next node */
+         next0 = tc0->c_rmt_dpo.dpoi_next_node;
+         vnet_buffer (b0)->ip.adj_index[VLIB_TX] = tc0->c_rmt_dpo.dpoi_index;
+#endif
+
          vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0;
-         vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
+         vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
 
-         b0->flags |= VNET_BUFFER_LOCALLY_ORIGINATED;
+         b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
        done:
          b0->error = node->errors[error0];
          if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
@@ -1630,7 +1690,7 @@ tcp_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
   tc = (tcp_connection_t *) tconn;
   tcp_push_hdr_i (tc, b, TCP_STATE_ESTABLISHED, 0);
 
-  if (tc->rtt_ts == 0)
+  if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
     {
       tc->rtt_ts = tcp_time_now ();
       tc->rtt_seq = tc->snd_nxt;
@@ -1702,7 +1762,7 @@ tcp46_send_reset_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
 
        done:
          b0->error = node->errors[error0];
-         b0->flags |= VNET_BUFFER_LOCALLY_ORIGINATED;
+         b0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED;
          if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
            {
              th0 = vlib_buffer_get_current (b0);