nat: add saddr info to nat44-ed o2i flow's rewrite
[vpp.git] / src / plugins / nat / nat44-ed / nat44_ed_in2out.c
index 23e0957..9b4dac3 100644 (file)
@@ -49,6 +49,7 @@ typedef struct
   u8 is_slow_path;
   u8 translation_via_i2of;
   u8 lookup_skipped;
+  u8 tcp_state;
 } nat_in2out_ed_trace_t;
 
 static u8 *
@@ -78,7 +79,7 @@ format_nat_in2out_ed_trace (u8 * s, va_list * args)
     {
       if (t->lookup_skipped)
        {
-         s = format (s, "\n lookup skipped - cached session index used");
+         s = format (s, "\n  lookup skipped - cached session index used");
        }
       else
        {
@@ -86,76 +87,13 @@ format_nat_in2out_ed_trace (u8 * s, va_list * args)
                      &t->search_key);
        }
     }
-
-  return s;
-}
-
-/**
- * @brief Check if packet should be translated
- *
- * Packets aimed at outside interface and external address with active session
- * should be translated.
- *
- * @param sm            NAT main
- * @param rt            NAT runtime data
- * @param sw_if_index0  index of the inside interface
- * @param ip0           IPv4 header
- * @param rx_fib_index0 RX FIB index
- *
- * @returns 0 if packet should be translated otherwise 1
- */
-static inline int
-snat_not_translate_fast (snat_main_t *sm, vlib_node_runtime_t *node,
-                        u32 sw_if_index0, ip4_header_t *ip0,
-                        u32 rx_fib_index0)
-{
-  fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
-  nat_outside_fib_t *outside_fib;
-  fib_prefix_t pfx = {
-    .fp_proto = FIB_PROTOCOL_IP4,
-    .fp_len = 32,
-    .fp_addr = {
-               .ip4.as_u32 = ip0->dst_address.as_u32,
-               }
-    ,
-  };
-
-  /* Don't NAT packet aimed at the intfc address */
-  if (PREDICT_FALSE (
-       is_interface_addr (sm, node, sw_if_index0, ip0->dst_address.as_u32)))
-    return 1;
-
-  fei = fib_table_lookup (rx_fib_index0, &pfx);
-  if (FIB_NODE_INDEX_INVALID != fei)
+  if (IP_PROTOCOL_TCP == t->i2of.match.proto)
     {
-      u32 sw_if_index = fib_entry_get_resolving_interface (fei);
-      if (sw_if_index == ~0)
-       {
-         vec_foreach (outside_fib, sm->outside_fibs)
-           {
-             fei = fib_table_lookup (outside_fib->fib_index, &pfx);
-             if (FIB_NODE_INDEX_INVALID != fei)
-               {
-                 sw_if_index = fib_entry_get_resolving_interface (fei);
-                 if (sw_if_index != ~0)
-                   break;
-               }
-           }
-       }
-      if (sw_if_index == ~0)
-       return 1;
-
-      snat_interface_t *i;
-      pool_foreach (i, sm->interfaces)
-       {
-         /* NAT packet aimed at outside interface */
-         if ((nat44_ed_is_interface_outside (i)) &&
-             (sw_if_index == i->sw_if_index))
-           return 0;
-       }
+      s = format (s, "\n  TCP state: %U", format_nat44_ed_tcp_state,
+                 t->tcp_state);
     }
 
-  return 1;
+  return s;
 }
 
 static int
@@ -164,14 +102,18 @@ nat_ed_alloc_addr_and_port_with_snat_address (
   u16 port_per_thread, u32 snat_thread_index, snat_session_t *s,
   ip4_address_t *outside_addr, u16 *outside_port)
 {
-  const u16 port_thread_offset = (port_per_thread * snat_thread_index) + 1024;
+  const u16 port_thread_offset =
+    (port_per_thread * snat_thread_index) + ED_USER_PORT_OFFSET;
+
+  /* Backup original match in case of failure */
+  const nat_6t_t match = s->o2i.match;
 
   s->o2i.match.daddr = a->addr;
   /* first try port suggested by caller */
   u16 port = clib_net_to_host_u16 (*outside_port);
   u16 port_offset = port - port_thread_offset;
-  if (port <= port_thread_offset ||
-      port > port_thread_offset + port_per_thread)
+  if (port < port_thread_offset ||
+      port >= port_thread_offset + port_per_thread)
     {
       /* need to pick a different port, suggested port doesn't fit in
        * this thread's port range */
@@ -197,6 +139,9 @@ nat_ed_alloc_addr_and_port_with_snat_address (
       --attempts;
     }
   while (attempts > 0);
+
+  /* Revert match */
+  s->o2i.match = match;
   return 1;
 }
 
@@ -210,7 +155,9 @@ nat_ed_alloc_addr_and_port (snat_main_t *sm, u32 rx_fib_index,
 {
   if (vec_len (sm->addresses) > 0)
     {
-      u32 s_addr_offset = s_addr.as_u32 % vec_len (sm->addresses);
+      u32 s_addr_offset = (s_addr.as_u32 + (s_addr.as_u32 >> 8) +
+                          (s_addr.as_u32 >> 16) + (s_addr.as_u32 >> 24)) %
+                         vec_len (sm->addresses);
       snat_address_t *a, *ja = 0, *ra = 0, *ba = 0;
       int i;
 
@@ -334,31 +281,6 @@ nat_ed_alloc_addr_and_port (snat_main_t *sm, u32 rx_fib_index,
   return 1;
 }
 
-static_always_inline u32
-nat_outside_fib_index_lookup (snat_main_t * sm, ip4_address_t addr)
-{
-  fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
-  nat_outside_fib_t *outside_fib;
-  fib_prefix_t pfx = {
-    .fp_proto = FIB_PROTOCOL_IP4,
-    .fp_len = 32,
-    .fp_addr = {.ip4.as_u32 = addr.as_u32,}
-    ,
-  };
-  vec_foreach (outside_fib, sm->outside_fibs)
-    {
-      fei = fib_table_lookup (outside_fib->fib_index, &pfx);
-      if (FIB_NODE_INDEX_INVALID != fei)
-        {
-          if (fib_entry_get_resolving_interface (fei) != ~0)
-            {
-              return outside_fib->fib_index;
-            }
-        }
-    }
-  return ~0;
-}
-
 static_always_inline int
 nat44_ed_external_sm_lookup (snat_main_t *sm, ip4_address_t match_addr,
                             u16 match_port, ip_protocol_t match_protocol,
@@ -382,6 +304,131 @@ nat44_ed_external_sm_lookup (snat_main_t *sm, ip4_address_t match_addr,
   return 1;
 }
 
+static_always_inline vrf_table_t *
+get_vrf_table_by_fib (u32 fib_index)
+{
+  snat_main_t *sm = &snat_main;
+  vrf_table_t *t;
+
+  pool_foreach (t, sm->vrf_tables)
+    {
+      if (fib_index == t->table_fib_index)
+       {
+         return t;
+       }
+    }
+
+  return 0;
+}
+
+static_always_inline u32
+get_tx_fib_index (u32 rx_fib_index, ip4_address_t addr)
+{
+  fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
+  fib_prefix_t pfx = {
+    .fp_proto = FIB_PROTOCOL_IP4,
+    .fp_len = 32,
+    .fp_addr = {.ip4.as_u32 = addr.as_u32,}
+    ,
+  };
+
+  snat_main_t *sm = &snat_main;
+  vrf_table_t *t = get_vrf_table_by_fib (rx_fib_index);
+  // default to rx fib
+  u32 tx_fib_index = rx_fib_index;
+
+  if (0 != t)
+    {
+      // managed routes to other fibs
+      vrf_route_t *r;
+      pool_foreach (r, t->routes)
+       {
+         fei = fib_table_lookup (r->fib_index, &pfx);
+         if ((FIB_NODE_INDEX_INVALID != fei) &&
+             (~0 != fib_entry_get_resolving_interface (fei)))
+           {
+             tx_fib_index = r->fib_index;
+             break;
+           }
+       }
+    }
+  else
+    {
+      // default to configured fib
+      tx_fib_index = sm->outside_fib_index;
+
+      // default routes to other fibs
+      nat_fib_t *f;
+      vec_foreach (f, sm->outside_fibs)
+       {
+         fei = fib_table_lookup (f->fib_index, &pfx);
+         if ((FIB_NODE_INDEX_INVALID != fei) &&
+             (~0 != fib_entry_get_resolving_interface (fei)))
+           {
+             tx_fib_index = f->fib_index;
+             break;
+           }
+       }
+    }
+
+  return tx_fib_index;
+}
+
+static_always_inline int
+is_destination_resolvable (u32 rx_fib_index, ip4_address_t addr)
+{
+  fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
+  fib_prefix_t pfx = {
+    .fp_proto = FIB_PROTOCOL_IP4,
+    .fp_len = 32,
+    .fp_addr = {.ip4.as_u32 = addr.as_u32,}
+    ,
+  };
+
+  snat_main_t *sm = &snat_main;
+  vrf_table_t *t = get_vrf_table_by_fib (rx_fib_index);
+  u32 ii;
+
+  if (0 != t)
+    {
+      // managed routes to other fibs
+      vrf_route_t *r;
+      pool_foreach (r, t->routes)
+       {
+         fei = fib_table_lookup (r->fib_index, &pfx);
+         if ((FIB_NODE_INDEX_INVALID != fei) &&
+             (~0 != (ii = fib_entry_get_resolving_interface (fei))))
+           {
+             return 1;
+           }
+       }
+    }
+  else
+    {
+      // default routes to other fibs
+      nat_fib_t *f;
+      vec_foreach (f, sm->outside_fibs)
+       {
+         fei = fib_table_lookup (f->fib_index, &pfx);
+         if ((FIB_NODE_INDEX_INVALID != fei) &&
+             (~0 != (ii = fib_entry_get_resolving_interface (fei))))
+           {
+             snat_interface_t *i;
+             pool_foreach (i, sm->interfaces)
+               {
+                 if ((nat44_ed_is_interface_outside (i)) &&
+                     (ii == i->sw_if_index))
+                   {
+                     return 1;
+                   }
+               }
+           }
+       }
+    }
+
+  return 0;
+}
+
 static u32
 slow_path_ed (vlib_main_t *vm, snat_main_t *sm, vlib_buffer_t *b,
              ip4_address_t l_addr, ip4_address_t r_addr, u16 l_port,
@@ -392,7 +439,7 @@ slow_path_ed (vlib_main_t *vm, snat_main_t *sm, vlib_buffer_t *b,
   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
   ip4_address_t outside_addr;
   u16 outside_port;
-  u32 outside_fib_index;
+  u32 tx_fib_index;
   u8 is_identity_nat = 0;
 
   snat_session_t *s = NULL;
@@ -413,33 +460,14 @@ slow_path_ed (vlib_main_t *vm, snat_main_t *sm, vlib_buffer_t *b,
        }
     }
 
-  outside_fib_index = sm->outside_fib_index;
-
-  switch (vec_len (sm->outside_fibs))
-    {
-    case 0:
-      outside_fib_index = sm->outside_fib_index;
-      break;
-    case 1:
-      outside_fib_index = sm->outside_fibs[0].fib_index;
-      break;
-    default:
-      outside_fib_index = nat_outside_fib_index_lookup (sm, r_addr);
-      break;
-    }
-
   ip4_address_t sm_addr;
   u16 sm_port;
   u32 sm_fib_index;
-  /* First try to match static mapping by local address and port */
-  int is_sm;
-  if (snat_static_mapping_match (vm, sm, l_addr, l_port, rx_fib_index, proto,
-                                &sm_addr, &sm_port, &sm_fib_index, 0, 0, 0,
-                                &lb, 0, &is_identity_nat, 0))
-    {
-      is_sm = 0;
-    }
-  else
+  int is_sm = 0;
+  // First try to match static mapping by local address and port
+  if (!snat_static_mapping_match (vm, l_addr, l_port, rx_fib_index, proto,
+                                 &sm_addr, &sm_port, &sm_fib_index, 0, 0, 0,
+                                 &lb, 0, &is_identity_nat, 0))
     {
       if (PREDICT_FALSE (is_identity_nat))
        {
@@ -462,21 +490,24 @@ slow_path_ed (vlib_main_t *vm, snat_main_t *sm, vlib_buffer_t *b,
   s = nat_ed_session_alloc (sm, thread_index, now, proto);
   ASSERT (s);
 
+  tx_fib_index = get_tx_fib_index (rx_fib_index, r_addr);
+
   if (!is_sm)
     {
       s->in2out.addr = l_addr;
       s->in2out.port = l_port;
       s->proto = proto;
       s->in2out.fib_index = rx_fib_index;
-      s->out2in.fib_index = outside_fib_index;
+      s->out2in.fib_index = tx_fib_index;
 
       // suggest using local port to allocation function
       outside_port = l_port;
 
-      // hairpinning?
-      int is_hairpinning = nat44_ed_external_sm_lookup (sm, r_addr, r_port,
-                                                       proto, &daddr, &dport);
-      s->flags |= is_hairpinning * SNAT_SESSION_FLAG_HAIRPINNING;
+      if (PREDICT_FALSE (nat44_ed_external_sm_lookup (sm, r_addr, r_port,
+                                                     proto, &daddr, &dport)))
+       {
+         s->flags |= SNAT_SESSION_FLAG_HAIRPINNING;
+       }
 
       // destination addr/port updated with real values in
       // nat_ed_alloc_addr_and_port
@@ -492,6 +523,7 @@ slow_path_ed (vlib_main_t *vm, snat_main_t *sm, vlib_buffer_t *b,
          nat_6t_flow_dport_rewrite_set (&s->o2i, l_port);
        }
       nat_6t_flow_txfib_rewrite_set (&s->o2i, rx_fib_index);
+      nat_6t_flow_saddr_rewrite_set (&s->o2i, r_addr.as_u32);
 
       if (nat_ed_alloc_addr_and_port (
            sm, rx_fib_index, tx_sw_if_index, proto, thread_index, l_addr,
@@ -514,7 +546,7 @@ slow_path_ed (vlib_main_t *vm, snat_main_t *sm, vlib_buffer_t *b,
       s->in2out.port = l_port;
       s->proto = proto;
       s->in2out.fib_index = rx_fib_index;
-      s->out2in.fib_index = outside_fib_index;
+      s->out2in.fib_index = tx_fib_index;
       s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 
       // hairpinning?
@@ -536,6 +568,7 @@ slow_path_ed (vlib_main_t *vm, snat_main_t *sm, vlib_buffer_t *b,
        }
       nat_6t_flow_daddr_rewrite_set (&s->o2i, l_addr.as_u32);
       nat_6t_flow_txfib_rewrite_set (&s->o2i, rx_fib_index);
+      nat_6t_flow_saddr_rewrite_set (&s->o2i, r_addr.as_u32);
       if (nat_ed_ses_o2i_flow_hash_add_del (sm, thread_index, s, 2))
        {
          nat_elog_notice (sm, "out2in key add failed");
@@ -562,7 +595,7 @@ slow_path_ed (vlib_main_t *vm, snat_main_t *sm, vlib_buffer_t *b,
       nat_6t_flow_sport_rewrite_set (&s->i2o, outside_port);
       nat_6t_flow_dport_rewrite_set (&s->i2o, dport);
     }
-  nat_6t_flow_txfib_rewrite_set (&s->i2o, outside_fib_index);
+  nat_6t_flow_txfib_rewrite_set (&s->i2o, tx_fib_index);
 
   if (nat_ed_ses_i2o_flow_hash_add_del (sm, thread_index, s, 1))
     {
@@ -594,38 +627,55 @@ error:
 }
 
 static_always_inline int
-nat44_ed_not_translate (vlib_main_t *vm, snat_main_t *sm,
-                       vlib_node_runtime_t *node, u32 sw_if_index,
-                       vlib_buffer_t *b, ip4_header_t *ip, u32 proto,
-                       u32 rx_fib_index)
+nat44_ed_not_translate (vlib_main_t *vm, vlib_node_runtime_t *node,
+                       u32 sw_if_index, vlib_buffer_t *b, ip4_header_t *ip,
+                       u32 proto, u32 rx_fib_index)
 {
+  snat_main_t *sm = &snat_main;
+
   clib_bihash_kv_16_8_t kv, value;
+  ip4_address_t placeholder_addr;
+  u32 placeholder_fib_index;
+  u16 placeholder_port;
 
   init_ed_k (&kv, ip->dst_address.as_u32,
             vnet_buffer (b)->ip.reass.l4_dst_port, ip->src_address.as_u32,
             vnet_buffer (b)->ip.reass.l4_src_port, sm->outside_fib_index,
             ip->protocol);
 
-  /* NAT packet aimed at external address if has active sessions */
-  if (clib_bihash_search_16_8 (&sm->flow_hash, &kv, &value))
+  // do nat if active session or is static mapping
+  if (!clib_bihash_search_16_8 (&sm->flow_hash, &kv, &value) ||
+      !snat_static_mapping_match (
+       vm, ip->dst_address, vnet_buffer (b)->ip.reass.l4_dst_port,
+       sm->outside_fib_index, proto, &placeholder_addr, &placeholder_port,
+       &placeholder_fib_index, 1, 0, 0, 0, 0, 0, 0))
     {
-      /* or is static mappings */
-      ip4_address_t placeholder_addr;
-      u16 placeholder_port;
-      u32 placeholder_fib_index;
-      if (!snat_static_mapping_match (
-           vm, sm, ip->dst_address, vnet_buffer (b)->ip.reass.l4_dst_port,
-           sm->outside_fib_index, proto, &placeholder_addr, &placeholder_port,
-           &placeholder_fib_index, 1, 0, 0, 0, 0, 0, 0))
-       return 0;
+      return 0;
     }
-  else
-    return 0;
 
+  // do not nat if forwarding enabled
   if (sm->forwarding_enabled)
-    return 1;
+    {
+      return 1;
+    }
+
+  // do not nat packet aimed at the interface address
+  if (PREDICT_FALSE (
+       is_interface_addr (sm, node, sw_if_index, ip->dst_address.as_u32)))
+    {
+      return 1;
+    }
 
-  return snat_not_translate_fast (sm, node, sw_if_index, ip, rx_fib_index);
+  // do nat packets with resolvable destination
+  // destination can be resolved either by:
+  // a) vrf routing table entry
+  // b) (non output feature) outside interface fib
+  if (is_destination_resolvable (rx_fib_index, ip->dst_address))
+    {
+      return 0;
+    }
+
+  return 1;
 }
 
 static_always_inline int
@@ -675,7 +725,9 @@ nat_not_translate_output_feature_fwd (snat_main_t * sm, ip4_header_t * ip,
        {
          if (ip->protocol == IP_PROTOCOL_TCP)
            {
-             nat44_set_tcp_session_state_i2o (sm, now, s, b, thread_index);
+             nat44_set_tcp_session_state_i2o (
+               sm, now, s, vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags,
+               thread_index);
            }
          /* Accounting */
          nat44_session_update_counters (s, now,
@@ -697,7 +749,7 @@ nat44_ed_not_translate_output_feature (snat_main_t *sm, vlib_buffer_t *b,
                                       ip4_header_t *ip, u16 src_port,
                                       u16 dst_port, u32 thread_index,
                                       u32 rx_sw_if_index, u32 tx_sw_if_index,
-                                      f64 now, int is_multi_worker)
+                                      int is_multi_worker)
 {
   clib_bihash_kv_16_8_t kv, value;
   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
@@ -715,12 +767,6 @@ nat44_ed_not_translate_output_feature (snat_main_t *sm, vlib_buffer_t *b,
       s =
        pool_elt_at_index (tsm->sessions,
                           ed_value_get_session_index (&value));
-      if (nat44_is_ses_closed (s)
-         && (!s->tcp_closed_timestamp || now >= s->tcp_closed_timestamp))
-       {
-         nat44_ed_free_session_data (sm, s, thread_index, 0);
-         nat_ed_session_delete (sm, s, thread_index, 1);
-       }
       return 1;
     }
 
@@ -800,7 +846,7 @@ icmp_in2out_ed_slow_path (snat_main_t *sm, vlib_buffer_t *b, ip4_header_t *ip,
     {
       if (PREDICT_FALSE (nat44_ed_not_translate_output_feature (
            sm, b, ip, lookup_sport, lookup_dport, thread_index, sw_if_index,
-           tx_sw_if_index, now, is_multi_worker)))
+           tx_sw_if_index, is_multi_worker)))
        {
          return next;
        }
@@ -808,7 +854,7 @@ icmp_in2out_ed_slow_path (snat_main_t *sm, vlib_buffer_t *b, ip4_header_t *ip,
   else
     {
       if (PREDICT_FALSE (nat44_ed_not_translate (
-           vm, sm, node, sw_if_index, b, ip, IP_PROTOCOL_ICMP, rx_fib_index)))
+           vm, node, sw_if_index, b, ip, IP_PROTOCOL_ICMP, rx_fib_index)))
        {
          return next;
        }
@@ -866,7 +912,7 @@ nat44_ed_in2out_slowpath_unknown_proto (snat_main_t *sm, vlib_buffer_t *b,
   snat_static_mapping_t *m = NULL;
   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
   snat_session_t *s = NULL;
-  u32 outside_fib_index = sm->outside_fib_index;
+  u32 tx_fib_index;
   int i;
   ip4_address_t new_src_addr = { 0 };
   ip4_address_t new_dst_addr = ip->dst_address;
@@ -881,20 +927,9 @@ nat44_ed_in2out_slowpath_unknown_proto (snat_main_t *sm, vlib_buffer_t *b,
       return 0;
     }
 
-  switch (vec_len (sm->outside_fibs))
-    {
-    case 0:
-      outside_fib_index = sm->outside_fib_index;
-      break;
-    case 1:
-      outside_fib_index = sm->outside_fibs[0].fib_index;
-      break;
-    default:
-      outside_fib_index = nat_outside_fib_index_lookup (sm, ip->dst_address);
-      break;
-    }
+  tx_fib_index = get_tx_fib_index (rx_fib_index, ip->dst_address);
 
-  /* Try to find static mapping first */
+  // Try to find static mapping first
   m = nat44_ed_sm_i2o_lookup (sm, ip->src_address, 0, rx_fib_index,
                              ip->protocol);
   if (m)
@@ -908,7 +943,7 @@ nat44_ed_in2out_slowpath_unknown_proto (snat_main_t *sm, vlib_buffer_t *b,
          if (s->ext_host_addr.as_u32 == ip->dst_address.as_u32)
            {
              init_ed_k (&s_kv, s->out2in.addr.as_u32, 0,
-                        ip->dst_address.as_u32, 0, outside_fib_index,
+                        ip->dst_address.as_u32, 0, tx_fib_index,
                         ip->protocol);
              if (clib_bihash_search_16_8 (&sm->flow_hash, &s_kv, &s_value))
                {
@@ -923,7 +958,7 @@ nat44_ed_in2out_slowpath_unknown_proto (snat_main_t *sm, vlib_buffer_t *b,
          for (i = 0; i < vec_len (sm->addresses); i++)
            {
              init_ed_k (&s_kv, sm->addresses[i].addr.as_u32, 0,
-                        ip->dst_address.as_u32, 0, outside_fib_index,
+                        ip->dst_address.as_u32, 0, tx_fib_index,
                         ip->protocol);
              if (clib_bihash_search_16_8 (&sm->flow_hash, &s_kv, &s_value))
                {
@@ -950,7 +985,7 @@ nat44_ed_in2out_slowpath_unknown_proto (snat_main_t *sm, vlib_buffer_t *b,
   nat_6t_i2o_flow_init (sm, thread_index, s, ip->src_address, 0,
                        ip->dst_address, 0, rx_fib_index, ip->protocol);
   nat_6t_flow_saddr_rewrite_set (&s->i2o, new_src_addr.as_u32);
-  nat_6t_flow_txfib_rewrite_set (&s->i2o, outside_fib_index);
+  nat_6t_flow_txfib_rewrite_set (&s->i2o, tx_fib_index);
 
   // hairpinning?
   int is_hairpinning = nat44_ed_external_sm_lookup (
@@ -958,17 +993,17 @@ nat44_ed_in2out_slowpath_unknown_proto (snat_main_t *sm, vlib_buffer_t *b,
   s->flags |= is_hairpinning * SNAT_SESSION_FLAG_HAIRPINNING;
 
   nat_6t_flow_daddr_rewrite_set (&s->i2o, new_dst_addr.as_u32);
-  nat_6t_flow_txfib_rewrite_set (&s->i2o, outside_fib_index);
+  nat_6t_flow_txfib_rewrite_set (&s->i2o, tx_fib_index);
 
   nat_6t_o2i_flow_init (sm, thread_index, s, new_dst_addr, 0, new_src_addr, 0,
-                       outside_fib_index, ip->protocol);
+                       tx_fib_index, ip->protocol);
   nat_6t_flow_saddr_rewrite_set (&s->o2i, ip->dst_address.as_u32);
   nat_6t_flow_daddr_rewrite_set (&s->o2i, ip->src_address.as_u32);
   nat_6t_flow_txfib_rewrite_set (&s->o2i, rx_fib_index);
 
   s->ext_host_addr.as_u32 = ip->dst_address.as_u32;
   s->out2in.addr.as_u32 = new_src_addr.as_u32;
-  s->out2in.fib_index = outside_fib_index;
+  s->out2in.fib_index = tx_fib_index;
   s->in2out.addr.as_u32 = ip->src_address.as_u32;
   s->in2out.fib_index = rx_fib_index;
   s->in2out.port = s->out2in.port = ip->protocol;
@@ -1031,7 +1066,7 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t *vm,
       ip_protocol_t proto0;
       ip4_header_t *ip0;
       snat_session_t *s0 = 0;
-      clib_bihash_kv_16_8_t kv0, value0;
+      clib_bihash_kv_16_8_t kv0 = { 0 }, value0;
       nat_translation_error_e translation_error = NAT_ED_TRNSL_ERR_SUCCESS;
       nat_6t_flow_t *f = 0;
       nat_6t_t lookup;
@@ -1169,23 +1204,8 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t *vm,
          // session is closed, go slow path
          nat44_ed_free_session_data (sm, s0, thread_index, 0);
          nat_ed_session_delete (sm, s0, thread_index, 1);
-         next[0] = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
-         goto trace0;
-       }
-
-      if (s0->tcp_closed_timestamp)
-       {
-         if (now >= s0->tcp_closed_timestamp)
-           {
-             // session is closed, go slow path, freed in slow path
-             next[0] = def_slow;
-           }
-         else
-           {
-             // session in transitory timeout, drop
-             b0->error = node->errors[NAT_IN2OUT_ED_ERROR_TCP_CLOSED];
-             next[0] = NAT_NEXT_DROP;
-           }
+         s0 = 0;
+         next[0] = def_slow;
          goto trace0;
        }
 
@@ -1197,6 +1217,7 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t *vm,
        {
          nat44_ed_free_session_data (sm, s0, thread_index, 0);
          nat_ed_session_delete (sm, s0, thread_index, 1);
+         s0 = 0;
          // session is closed, go slow path
          next[0] = def_slow;
          goto trace0;
@@ -1218,6 +1239,7 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t *vm,
          translation_error = NAT_ED_TRNSL_ERR_FLOW_MISMATCH;
          nat44_ed_free_session_data (sm, s0, thread_index, 0);
          nat_ed_session_delete (sm, s0, thread_index, 1);
+         s0 = 0;
          next[0] = NAT_NEXT_DROP;
          b0->error = node->errors[NAT_IN2OUT_ED_ERROR_TRNSL_FAILED];
          goto trace0;
@@ -1229,6 +1251,7 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t *vm,
        {
          nat44_ed_free_session_data (sm, s0, thread_index, 0);
          nat_ed_session_delete (sm, s0, thread_index, 1);
+         s0 = 0;
          next[0] = NAT_NEXT_DROP;
          b0->error = node->errors[NAT_IN2OUT_ED_ERROR_TRNSL_FAILED];
          goto trace0;
@@ -1239,7 +1262,9 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t *vm,
        case IP_PROTOCOL_TCP:
          vlib_increment_simple_counter (&sm->counters.fastpath.in2out.tcp,
                                         thread_index, cntr_sw_if_index0, 1);
-         nat44_set_tcp_session_state_i2o (sm, now, s0, b0, thread_index);
+         nat44_set_tcp_session_state_i2o (
+           sm, now, s0, vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags,
+           thread_index);
          break;
        case IP_PROTOCOL_UDP:
          vlib_increment_simple_counter (&sm->counters.fastpath.in2out.udp,
@@ -1282,6 +1307,7 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t *vm,
              clib_memcpy (&t->i2of, &s0->i2o, sizeof (t->i2of));
              clib_memcpy (&t->o2if, &s0->o2i, sizeof (t->o2if));
              t->translation_via_i2of = (&s0->i2o == f);
+             t->tcp_state = s0->tcp_state;
            }
          else
            {
@@ -1335,7 +1361,7 @@ nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t *vm,
       udp_header_t *udp0;
       icmp46_header_t *icmp0;
       snat_session_t *s0 = 0;
-      clib_bihash_kv_16_8_t kv0, value0;
+      clib_bihash_kv_16_8_t kv0 = { 0 }, value0;
       int translation_error = NAT_ED_TRNSL_ERR_SUCCESS;
 
       b0 = *b;
@@ -1383,6 +1409,7 @@ nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t *vm,
            {
              nat44_ed_free_session_data (sm, s0, thread_index, 0);
              nat_ed_session_delete (sm, s0, thread_index, 1);
+             s0 = 0;
              next[0] = NAT_NEXT_DROP;
              b0->error = node->errors[NAT_IN2OUT_ED_ERROR_TRNSL_FAILED];
              goto trace0;
@@ -1406,13 +1433,18 @@ nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t *vm,
            {
              nat44_ed_free_session_data (sm, s0, thread_index, 0);
              nat_ed_session_delete (sm, s0, thread_index, 1);
+             s0 = 0;
              next[0] = NAT_NEXT_DROP;
              b0->error = node->errors[NAT_IN2OUT_ED_ERROR_TRNSL_FAILED];
              goto trace0;
            }
 
-         vlib_increment_simple_counter (&sm->counters.slowpath.in2out.icmp,
-                                        thread_index, cntr_sw_if_index0, 1);
+         if (NAT_NEXT_DROP != next[0])
+           {
+             vlib_increment_simple_counter (
+               &sm->counters.slowpath.in2out.icmp, thread_index,
+               cntr_sw_if_index0, 1);
+           }
          goto trace0;
        }
 
@@ -1426,13 +1458,6 @@ nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t *vm,
          s0 =
            pool_elt_at_index (tsm->sessions,
                               ed_value_get_session_index (&value0));
-
-         if (s0->tcp_closed_timestamp && now >= s0->tcp_closed_timestamp)
-           {
-             nat44_ed_free_session_data (sm, s0, thread_index, 0);
-             nat_ed_session_delete (sm, s0, thread_index, 1);
-             s0 = NULL;
-           }
        }
 
       if (!s0)
@@ -1442,7 +1467,7 @@ nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t *vm,
              if (PREDICT_FALSE (nat44_ed_not_translate_output_feature (
                    sm, b0, ip0, vnet_buffer (b0)->ip.reass.l4_src_port,
                    vnet_buffer (b0)->ip.reass.l4_dst_port, thread_index,
-                   rx_sw_if_index0, tx_sw_if_index0, now, is_multi_worker)))
+                   rx_sw_if_index0, tx_sw_if_index0, is_multi_worker)))
                goto trace0;
 
              /*
@@ -1459,8 +1484,8 @@ nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t *vm,
          else
            {
              if (PREDICT_FALSE (
-                   nat44_ed_not_translate (vm, sm, node, rx_sw_if_index0, b0,
-                                           ip0, proto0, rx_fib_index0)))
+                   nat44_ed_not_translate (vm, node, rx_sw_if_index0, b0, ip0,
+                                           proto0, rx_fib_index0)))
                goto trace0;
            }
 
@@ -1487,6 +1512,7 @@ nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t *vm,
        {
          nat44_ed_free_session_data (sm, s0, thread_index, 0);
          nat_ed_session_delete (sm, s0, thread_index, 1);
+         s0 = 0;
          next[0] = NAT_NEXT_DROP;
          b0->error = node->errors[NAT_IN2OUT_ED_ERROR_TRNSL_FAILED];
          goto trace0;
@@ -1496,7 +1522,9 @@ nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t *vm,
        {
          vlib_increment_simple_counter (&sm->counters.slowpath.in2out.tcp,
                                         thread_index, cntr_sw_if_index0, 1);
-         nat44_set_tcp_session_state_i2o (sm, now, s0, b0, thread_index);
+         nat44_set_tcp_session_state_i2o (
+           sm, now, s0, vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags,
+           thread_index);
        }
       else
        {
@@ -1529,6 +1557,7 @@ nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t *vm,
              clib_memcpy (&t->i2of, &s0->i2o, sizeof (t->i2of));
              clib_memcpy (&t->o2if, &s0->o2i, sizeof (t->o2if));
              t->translation_via_i2of = 1;
+             t->tcp_state = s0->tcp_state;
            }
 
          else