CGN: Send ICMP error packet if user is out of sessions available
[vpp.git] / src / plugins / snat / in2out.c
index f544376..f7d29c6 100644 (file)
@@ -94,7 +94,7 @@ _(UNSUPPORTED_PROTOCOL, "Unsupported protocol")         \
 _(IN2OUT_PACKETS, "Good in2out packets processed")      \
 _(OUT_OF_PORTS, "Out of ports")                         \
 _(BAD_OUTSIDE_FIB, "Outside VRF ID not found")          \
-_(BAD_ICMP_TYPE, "icmp type not echo-request")          \
+_(BAD_ICMP_TYPE, "unsupported ICMP type")               \
 _(NO_TRANSLATION, "No translation")
   
 typedef enum {
@@ -194,7 +194,7 @@ snat_not_translate (snat_main_t * sm, vlib_node_runtime_t *node,
   if (clib_bihash_search_8_8 (&sm->out2in, &kv0, &value0))
     {
       /* or is static mappings */
-      if (!snat_static_mapping_match(sm, key0, &sm0, 1))
+      if (!snat_static_mapping_match(sm, key0, &sm0, 1, 0))
         return 0;
     }
   else
@@ -332,7 +332,7 @@ static u32 slow_path (snat_main_t *sm, vlib_buffer_t *b0,
       u8 static_mapping = 1;
 
       /* First try to match static mapping by local address and port */
-      if (snat_static_mapping_match (sm, *key0, &key1, 0))
+      if (snat_static_mapping_match (sm, *key0, &key1, 0, 0))
         {
           static_mapping = 0;
           /* Try to create dynamic translation */
@@ -472,11 +472,12 @@ snat_in2out_error_t icmp_get_key(ip4_header_t *ip0,
  * @param[out] p_value           address and port after NAT translation
  * @param[out] p_dont_translate  if packet should not be translated
  * @param d                      optional parameter
+ * @param e                      optional parameter
  */
 u32 icmp_match_in2out_slow(snat_main_t *sm, vlib_node_runtime_t *node,
                            u32 thread_index, vlib_buffer_t *b0, u8 *p_proto,
                            snat_session_key_t *p_value,
-                           u8 *p_dont_translate, void *d)
+                           u8 *p_dont_translate, void *d, void *e)
 {
   ip4_header_t *ip0;
   icmp46_header_t *icmp0;
@@ -514,8 +515,9 @@ u32 icmp_match_in2out_slow(snat_main_t *sm, vlib_node_runtime_t *node,
           goto out;
         }
 
-      if (icmp_is_error_message (icmp0))
+      if (PREDICT_FALSE(icmp0->type != ICMP4_echo_request))
         {
+          b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
           next0 = SNAT_IN2OUT_NEXT_DROP;
           goto out;
         }
@@ -527,15 +529,18 @@ u32 icmp_match_in2out_slow(snat_main_t *sm, vlib_node_runtime_t *node,
         goto out;
     }
   else
-    s0 = pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
-                            value0.value);
-
-  if (PREDICT_FALSE(icmp0->type != ICMP4_echo_request &&
-                    !icmp_is_error_message (icmp0)))
     {
-      b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
-      next0 = SNAT_IN2OUT_NEXT_DROP;
-      goto out;
+      if (PREDICT_FALSE(icmp0->type != ICMP4_echo_request &&
+                        icmp0->type != ICMP4_echo_reply &&
+                        !icmp_is_error_message (icmp0)))
+        {
+          b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
+          next0 = SNAT_IN2OUT_NEXT_DROP;
+          goto out;
+        }
+
+      s0 = pool_elt_at_index (sm->per_thread_data[thread_index].sessions,
+                              value0.value);
     }
 
 out:
@@ -559,11 +564,12 @@ out:
  * @param[out] p_value           address and port after NAT translation
  * @param[out] p_dont_translate  if packet should not be translated
  * @param d                      optional parameter
+ * @param e                      optional parameter
  */
 u32 icmp_match_in2out_fast(snat_main_t *sm, vlib_node_runtime_t *node,
                            u32 thread_index, vlib_buffer_t *b0, u8 *p_proto,
                            snat_session_key_t *p_value,
-                           u8 *p_dont_translate, void *d)
+                           u8 *p_dont_translate, void *d, void *e)
 {
   ip4_header_t *ip0;
   icmp46_header_t *icmp0;
@@ -572,6 +578,7 @@ u32 icmp_match_in2out_fast(snat_main_t *sm, vlib_node_runtime_t *node,
   snat_session_key_t key0;
   snat_session_key_t sm0;
   u8 dont_translate = 0;
+  u8 is_addr_only;
   u32 next0 = ~0;
   int err;
 
@@ -589,7 +596,7 @@ u32 icmp_match_in2out_fast(snat_main_t *sm, vlib_node_runtime_t *node,
     }
   key0.fib_index = rx_fib_index0;
 
-  if (snat_static_mapping_match(sm, key0, &sm0, 0))
+  if (snat_static_mapping_match(sm, key0, &sm0, 0, &is_addr_only))
     {
       if (PREDICT_FALSE(snat_not_translate_fast(sm, node, sw_if_index0, ip0,
           IP_PROTOCOL_ICMP, rx_fib_index0)))
@@ -610,14 +617,12 @@ u32 icmp_match_in2out_fast(snat_main_t *sm, vlib_node_runtime_t *node,
     }
 
   if (PREDICT_FALSE(icmp0->type != ICMP4_echo_request &&
+                    (icmp0->type != ICMP4_echo_reply || !is_addr_only) &&
                     !icmp_is_error_message (icmp0)))
     {
-      if (icmp0->type != ICMP4_echo_reply || key0.port != sm0.port)
-        {
-          b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
-          next0 = SNAT_IN2OUT_NEXT_DROP;
-          goto out;
-        }
+      b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
+      next0 = SNAT_IN2OUT_NEXT_DROP;
+      goto out;
     }
 
 out:
@@ -637,7 +642,8 @@ static inline u32 icmp_in2out (snat_main_t *sm,
                                vlib_node_runtime_t * node,
                                u32 next0,
                                u32 thread_index,
-                               void *d)
+                               void *d,
+                               void *e)
 {
   snat_session_key_t sm0;
   u8 protocol;
@@ -655,7 +661,7 @@ static inline u32 icmp_in2out (snat_main_t *sm,
   echo0 = (icmp_echo_header_t *)(icmp0+1);
 
   next0_tmp = sm->icmp_match_in2out_cb(sm, node, thread_index, b0,
-                                       &protocol, &sm0, &dont_translate, d);
+                                       &protocol, &sm0, &dont_translate, d, e);
   if (next0_tmp != ~0)
     next0 = next0_tmp;
   if (next0 == SNAT_IN2OUT_NEXT_DROP || dont_translate)
@@ -789,7 +795,7 @@ snat_hairpinning (snat_main_t *sm,
   if (clib_bihash_search_8_8 (&sm->out2in, &kv0, &value0))
     {
       /* or static mappings */
-      if (!snat_static_mapping_match(sm, key0, &sm0, 1))
+      if (!snat_static_mapping_match(sm, key0, &sm0, 1, 0))
         {
           new_dst_addr0 = sm0.addr.as_u32;
           new_dst_port0 = sm0.port;
@@ -864,7 +870,7 @@ static inline u32 icmp_in2out_slow_path (snat_main_t *sm,
                                          snat_session_t ** p_s0)
 {
   next0 = icmp_in2out(sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
-                      next0, thread_index, p_s0);
+                      next0, thread_index, p_s0, 0);
   snat_session_t * s0 = *p_s0;
   if (PREDICT_TRUE(next0 != SNAT_IN2OUT_NEXT_DROP && s0))
     {
@@ -1508,6 +1514,7 @@ snat_det_in2out_node_fn (vlib_main_t * vm,
   u32 pkts_processed = 0;
   snat_main_t * sm = &snat_main;
   u32 now = (u32) vlib_time_now (vm);
+  u32 thread_index = os_get_cpu_number ();
 
   from = vlib_frame_vector_args (frame);
   n_left_from = frame->n_vectors;
@@ -1537,6 +1544,8 @@ snat_det_in2out_node_fn (vlib_main_t * vm,
           snat_det_out_key_t key0, key1;
           snat_det_map_t * dm0, * dm1;
           snat_det_session_t * ses0 = 0, * ses1 = 0;
+          u32 rx_fib_index0, rx_fib_index1;
+          icmp46_header_t * icmp0, * icmp1;
 
          /* Prefetch next iteration. */
          {
@@ -1582,6 +1591,19 @@ snat_det_in2out_node_fn (vlib_main_t * vm,
               goto trace0;
             }
 
+          proto0 = ip_proto_to_snat_proto (ip0->protocol);
+
+          if (PREDICT_FALSE(proto0 == SNAT_PROTOCOL_ICMP))
+            {
+              rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index(sw_if_index0);
+              icmp0 = (icmp46_header_t *) udp0;
+
+              next0 = icmp_in2out(sm, b0, ip0, icmp0, sw_if_index0,
+                                  rx_fib_index0, node, next0, thread_index,
+                                  &ses0, &dm0);
+              goto trace0;
+            }
+
           dm0 = snat_det_map_by_user(sm, &ip0->src_address);
           if (PREDICT_FALSE(!dm0))
             {
@@ -1594,11 +1616,12 @@ snat_det_in2out_node_fn (vlib_main_t * vm,
 
           snat_det_forward(dm0, &ip0->src_address, &new_addr0, &lo_port0);
 
-          ses0 = snat_det_find_ses_by_in(dm0, &ip0->src_address, tcp0->src);
+          key0.ext_host_addr = ip0->dst_address;
+          key0.ext_host_port = tcp0->dst;
+
+          ses0 = snat_det_find_ses_by_in(dm0, &ip0->src_address, tcp0->src, key0);
           if (PREDICT_FALSE(!ses0))
             {
-              key0.ext_host_addr = ip0->dst_address;
-              key0.ext_host_port = tcp0->dst;
               for (i0 = 0; i0 < dm0->ports_per_host; i0++)
                 {
                   key0.out_port = clib_host_to_net_u16 (lo_port0 +
@@ -1612,14 +1635,18 @@ snat_det_in2out_node_fn (vlib_main_t * vm,
                 }
               if (PREDICT_FALSE(!ses0))
                 {
-                  next0 = SNAT_IN2OUT_NEXT_DROP;
-                  b0->error = node->errors[SNAT_IN2OUT_ERROR_OUT_OF_PORTS];
+                  /* too many sessions for user, send ICMP error packet */
+
+                  vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
+                  icmp4_error_set_vnet_buffer (b0, ICMP4_destination_unreachable,
+                                               ICMP4_destination_unreachable_destination_unreachable_host,
+                                               0);
+                  next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
                   goto trace0;
                 }
             }
 
           new_port0 = ses0->out.out_port;
-          proto0 = ip_proto_to_snat_proto (ip0->protocol);
 
           old_addr0.as_u32 = ip0->src_address.as_u32;
           ip0->src_address.as_u32 = new_addr0.as_u32;
@@ -1669,16 +1696,16 @@ snat_det_in2out_node_fn (vlib_main_t * vm,
           switch(ses0->state)
             {
             case SNAT_SESSION_UDP_ACTIVE:
-                ses0->expire = now + SNAT_UDP_TIMEOUT;
+                ses0->expire = now + sm->udp_timeout;
                 break;
             case SNAT_SESSION_TCP_SYN_SENT:
             case SNAT_SESSION_TCP_FIN_WAIT:
             case SNAT_SESSION_TCP_CLOSE_WAIT:
             case SNAT_SESSION_TCP_LAST_ACK:
-                ses0->expire = now + SNAT_TCP_TRANSITORY_TIMEOUT;
+                ses0->expire = now + sm->tcp_transitory_timeout;
                 break;
             case SNAT_SESSION_TCP_ESTABLISHED:
-                ses0->expire = now + SNAT_TCP_ESTABLISHED_TIMEOUT;
+                ses0->expire = now + sm->tcp_established_timeout;
                 break;
             }
 
@@ -1714,6 +1741,19 @@ snat_det_in2out_node_fn (vlib_main_t * vm,
               goto trace1;
             }
 
+          proto1 = ip_proto_to_snat_proto (ip1->protocol);
+
+          if (PREDICT_FALSE(proto1 == SNAT_PROTOCOL_ICMP))
+            {
+              rx_fib_index1 = ip4_fib_table_get_index_for_sw_if_index(sw_if_index1);
+              icmp1 = (icmp46_header_t *) udp1;
+
+              next1 = icmp_in2out(sm, b1, ip1, icmp1, sw_if_index1,
+                                  rx_fib_index1, node, next1, thread_index,
+                                  &ses1, &dm1);
+              goto trace1;
+            }
+
           dm1 = snat_det_map_by_user(sm, &ip1->src_address);
           if (PREDICT_FALSE(!dm1))
             {
@@ -1726,11 +1766,12 @@ snat_det_in2out_node_fn (vlib_main_t * vm,
 
           snat_det_forward(dm1, &ip1->src_address, &new_addr1, &lo_port1);
 
-          ses1 = snat_det_find_ses_by_in(dm1, &ip1->src_address, tcp1->src);
+          key1.ext_host_addr = ip1->dst_address;
+          key1.ext_host_port = tcp1->dst;
+
+          ses1 = snat_det_find_ses_by_in(dm1, &ip1->src_address, tcp1->src, key1);
           if (PREDICT_FALSE(!ses1))
             {
-              key1.ext_host_addr = ip1->dst_address;
-              key1.ext_host_port = tcp1->dst;
               for (i1 = 0; i1 < dm1->ports_per_host; i1++)
                 {
                   key1.out_port = clib_host_to_net_u16 (lo_port1 +
@@ -1744,14 +1785,18 @@ snat_det_in2out_node_fn (vlib_main_t * vm,
                 }
               if (PREDICT_FALSE(!ses1))
                 {
-                  next1 = SNAT_IN2OUT_NEXT_DROP;
-                  b1->error = node->errors[SNAT_IN2OUT_ERROR_OUT_OF_PORTS];
+                  /* too many sessions for user, send ICMP error packet */
+
+                  vnet_buffer (b1)->sw_if_index[VLIB_TX] = (u32) ~ 0;
+                  icmp4_error_set_vnet_buffer (b1, ICMP4_destination_unreachable,
+                                               ICMP4_destination_unreachable_destination_unreachable_host,
+                                               0);
+                  next1 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
                   goto trace1;
                 }
             }
 
           new_port1 = ses1->out.out_port;
-          proto1 = ip_proto_to_snat_proto (ip1->protocol);
 
           old_addr1.as_u32 = ip1->src_address.as_u32;
           ip1->src_address.as_u32 = new_addr1.as_u32;
@@ -1801,16 +1846,16 @@ snat_det_in2out_node_fn (vlib_main_t * vm,
           switch(ses1->state)
             {
             case SNAT_SESSION_UDP_ACTIVE:
-                ses1->expire = now + SNAT_UDP_TIMEOUT;
+                ses1->expire = now + sm->udp_timeout;
                 break;
             case SNAT_SESSION_TCP_SYN_SENT:
             case SNAT_SESSION_TCP_FIN_WAIT:
             case SNAT_SESSION_TCP_CLOSE_WAIT:
             case SNAT_SESSION_TCP_LAST_ACK:
-                ses1->expire = now + SNAT_TCP_TRANSITORY_TIMEOUT;
+                ses1->expire = now + sm->tcp_transitory_timeout;
                 break;
             case SNAT_SESSION_TCP_ESTABLISHED:
-                ses1->expire = now + SNAT_TCP_ESTABLISHED_TIMEOUT;
+                ses1->expire = now + sm->tcp_established_timeout;
                 break;
             }
 
@@ -1852,6 +1897,8 @@ snat_det_in2out_node_fn (vlib_main_t * vm,
           snat_det_out_key_t key0;
           snat_det_map_t * dm0;
           snat_det_session_t * ses0 = 0;
+          u32 rx_fib_index0;
+          icmp46_header_t * icmp0;
 
           /* speculatively enqueue b0 to the current next frame */
          bi0 = from[0];
@@ -1880,6 +1927,19 @@ snat_det_in2out_node_fn (vlib_main_t * vm,
               goto trace00;
             }
 
+          proto0 = ip_proto_to_snat_proto (ip0->protocol);
+
+          if (PREDICT_FALSE(proto0 == SNAT_PROTOCOL_ICMP))
+            {
+              rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index(sw_if_index0);
+              icmp0 = (icmp46_header_t *) udp0;
+
+              next0 = icmp_in2out(sm, b0, ip0, icmp0, sw_if_index0,
+                                  rx_fib_index0, node, next0, thread_index,
+                                  &ses0, &dm0);
+              goto trace00;
+            }
+
           dm0 = snat_det_map_by_user(sm, &ip0->src_address);
           if (PREDICT_FALSE(!dm0))
             {
@@ -1892,11 +1952,12 @@ snat_det_in2out_node_fn (vlib_main_t * vm,
 
           snat_det_forward(dm0, &ip0->src_address, &new_addr0, &lo_port0);
 
-          ses0 = snat_det_find_ses_by_in(dm0, &ip0->src_address, tcp0->src);
+          key0.ext_host_addr = ip0->dst_address;
+          key0.ext_host_port = tcp0->dst;
+
+          ses0 = snat_det_find_ses_by_in(dm0, &ip0->src_address, tcp0->src, key0);
           if (PREDICT_FALSE(!ses0))
             {
-              key0.ext_host_addr = ip0->dst_address;
-              key0.ext_host_port = tcp0->dst;
               for (i0 = 0; i0 < dm0->ports_per_host; i0++)
                 {
                   key0.out_port = clib_host_to_net_u16 (lo_port0 +
@@ -1910,14 +1971,18 @@ snat_det_in2out_node_fn (vlib_main_t * vm,
                 }
               if (PREDICT_FALSE(!ses0))
                 {
-                  next0 = SNAT_IN2OUT_NEXT_DROP;
-                  b0->error = node->errors[SNAT_IN2OUT_ERROR_OUT_OF_PORTS];
+                  /* too many sessions for user, send ICMP error packet */
+
+                  vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
+                  icmp4_error_set_vnet_buffer (b0, ICMP4_destination_unreachable,
+                                               ICMP4_destination_unreachable_destination_unreachable_host,
+                                               0);
+                  next0 = SNAT_IN2OUT_NEXT_ICMP_ERROR;
                   goto trace00;
                 }
             }
 
           new_port0 = ses0->out.out_port;
-          proto0 = ip_proto_to_snat_proto (ip0->protocol);
 
           old_addr0.as_u32 = ip0->src_address.as_u32;
           ip0->src_address.as_u32 = new_addr0.as_u32;
@@ -1967,16 +2032,16 @@ snat_det_in2out_node_fn (vlib_main_t * vm,
           switch(ses0->state)
             {
             case SNAT_SESSION_UDP_ACTIVE:
-                ses0->expire = now + SNAT_UDP_TIMEOUT;
+                ses0->expire = now + sm->udp_timeout;
                 break;
             case SNAT_SESSION_TCP_SYN_SENT:
             case SNAT_SESSION_TCP_FIN_WAIT:
             case SNAT_SESSION_TCP_CLOSE_WAIT:
             case SNAT_SESSION_TCP_LAST_ACK:
-                ses0->expire = now + SNAT_TCP_TRANSITORY_TIMEOUT;
+                ses0->expire = now + sm->tcp_transitory_timeout;
                 break;
             case SNAT_SESSION_TCP_ESTABLISHED:
-                ses0->expire = now + SNAT_TCP_ESTABLISHED_TIMEOUT;
+                ses0->expire = now + sm->tcp_established_timeout;
                 break;
             }
 
@@ -2035,6 +2100,164 @@ VLIB_REGISTER_NODE (snat_det_in2out_node) = {
 
 VLIB_NODE_FUNCTION_MULTIARCH (snat_det_in2out_node, snat_det_in2out_node_fn);
 
+/**
+ * Get address and port values to be used for packet SNAT translation
+ * and create session if needed
+ *
+ * @param[in,out] sm             SNAT main
+ * @param[in,out] node           SNAT node runtime
+ * @param[in] thread_index       thread index
+ * @param[in,out] b0             buffer containing packet to be translated
+ * @param[out] p_proto           protocol used for matching
+ * @param[out] p_value           address and port after NAT translation
+ * @param[out] p_dont_translate  if packet should not be translated
+ * @param d                      optional parameter
+ * @param e                      optional parameter
+ */
+u32 icmp_match_in2out_det(snat_main_t *sm, vlib_node_runtime_t *node,
+                          u32 thread_index, vlib_buffer_t *b0, u8 *p_proto,
+                          snat_session_key_t *p_value,
+                          u8 *p_dont_translate, void *d, void *e)
+{
+  ip4_header_t *ip0;
+  icmp46_header_t *icmp0;
+  u32 sw_if_index0;
+  u32 rx_fib_index0;
+  u8 protocol;
+  snat_det_out_key_t key0;
+  u8 dont_translate = 0;
+  u32 next0 = ~0;
+  icmp_echo_header_t *echo0, *inner_echo0 = 0;
+  ip4_header_t *inner_ip0;
+  void *l4_header = 0;
+  icmp46_header_t *inner_icmp0;
+  snat_det_map_t * dm0 = 0;
+  ip4_address_t new_addr0;
+  u16 lo_port0, i0;
+  snat_det_session_t * ses0 = 0;
+  ip4_address_t in_addr;
+  u16 in_port;
+
+  ip0 = vlib_buffer_get_current (b0);
+  icmp0 = (icmp46_header_t *) ip4_next_header (ip0);
+  echo0 = (icmp_echo_header_t *)(icmp0+1);
+  sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_RX];
+  rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
+
+  if (!icmp_is_error_message (icmp0))
+    {
+      protocol = SNAT_PROTOCOL_ICMP;
+      in_addr = ip0->src_address;
+      in_port = echo0->identifier;
+    }
+  else
+    {
+      inner_ip0 = (ip4_header_t *)(echo0+1);
+      l4_header = ip4_next_header (inner_ip0);
+      protocol = ip_proto_to_snat_proto (inner_ip0->protocol);
+      in_addr = inner_ip0->dst_address;
+      switch (protocol)
+        {
+        case SNAT_PROTOCOL_ICMP:
+          inner_icmp0 = (icmp46_header_t*)l4_header;
+          inner_echo0 = (icmp_echo_header_t *)(inner_icmp0+1);
+          in_port = inner_echo0->identifier;
+          break;
+        case SNAT_PROTOCOL_UDP:
+        case SNAT_PROTOCOL_TCP:
+          in_port = ((tcp_udp_header_t*)l4_header)->dst_port;
+          break;
+        default:
+          b0->error = node->errors[SNAT_IN2OUT_ERROR_UNSUPPORTED_PROTOCOL];
+          next0 = SNAT_IN2OUT_NEXT_DROP;
+          goto out;
+        }
+    }
+
+  dm0 = snat_det_map_by_user(sm, &in_addr);
+  if (PREDICT_FALSE(!dm0))
+    {
+      clib_warning("no match for internal host %U",
+                   format_ip4_address, &in_addr);
+      if (PREDICT_FALSE(snat_not_translate_fast(sm, node, sw_if_index0, ip0,
+          IP_PROTOCOL_ICMP, rx_fib_index0)))
+        {
+          dont_translate = 1;
+          goto out;
+        }
+      next0 = SNAT_IN2OUT_NEXT_DROP;
+      b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
+      goto out;
+    }
+
+  snat_det_forward(dm0, &in_addr, &new_addr0, &lo_port0);
+
+  key0.ext_host_addr = ip0->dst_address;
+  key0.ext_host_port = 0;
+
+  ses0 = snat_det_find_ses_by_in(dm0, &in_addr, in_port, key0);
+  if (PREDICT_FALSE(!ses0))
+    {
+      if (PREDICT_FALSE(snat_not_translate_fast(sm, node, sw_if_index0, ip0,
+          IP_PROTOCOL_ICMP, rx_fib_index0)))
+        {
+          dont_translate = 1;
+          goto out;
+        }
+      if (icmp0->type != ICMP4_echo_request)
+        {
+          b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
+          next0 = SNAT_IN2OUT_NEXT_DROP;
+          goto out;
+        }
+      for (i0 = 0; i0 < dm0->ports_per_host; i0++)
+        {
+          key0.out_port = clib_host_to_net_u16 (lo_port0 +
+            ((i0 + clib_net_to_host_u16 (echo0->identifier)) % dm0->ports_per_host));
+
+          if (snat_det_get_ses_by_out (dm0, &in_addr, key0.as_u64))
+            continue;
+
+          ses0 = snat_det_ses_create(dm0, &in_addr, echo0->identifier, &key0);
+          break;
+        }
+      if (PREDICT_FALSE(!ses0))
+        {
+          next0 = SNAT_IN2OUT_NEXT_DROP;
+          b0->error = node->errors[SNAT_IN2OUT_ERROR_OUT_OF_PORTS];
+          goto out;
+        }
+    }
+
+  if (PREDICT_FALSE(icmp0->type != ICMP4_echo_request &&
+                    !icmp_is_error_message (icmp0)))
+    {
+      b0->error = node->errors[SNAT_IN2OUT_ERROR_BAD_ICMP_TYPE];
+      next0 = SNAT_IN2OUT_NEXT_DROP;
+      goto out;
+    }
+
+  u32 now = (u32) vlib_time_now (sm->vlib_main);
+
+  ses0->state = SNAT_SESSION_ICMP_ACTIVE;
+  ses0->expire = now + sm->icmp_timeout;
+
+out:
+  *p_proto = protocol;
+  if (ses0)
+    {
+      p_value->addr = new_addr0;
+      p_value->fib_index = sm->outside_fib_index;
+      p_value->port = ses0->out.out_port;
+    }
+  *p_dont_translate = dont_translate;
+  if (d)
+    *(snat_det_session_t**)d = ses0;
+  if (e)
+    *(snat_det_map_t**)e = dm0;
+  return next0;
+}
+
 /**********************/
 /*** worker handoff ***/
 /**********************/
@@ -2276,7 +2499,7 @@ snat_in2out_fast_static_map_fn (vlib_main_t * vm,
           if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
             {
               next0 = icmp_in2out(sm, b0, ip0, icmp0, sw_if_index0,
-                                  rx_fib_index0, node, next0, ~0, 0);
+                                  rx_fib_index0, node, next0, ~0, 0, 0);
               goto trace0;
             }
 
@@ -2284,7 +2507,7 @@ snat_in2out_fast_static_map_fn (vlib_main_t * vm,
           key0.port = udp0->src_port;
           key0.fib_index = rx_fib_index0;
 
-          if (snat_static_mapping_match(sm, key0, &sm0, 0))
+          if (snat_static_mapping_match(sm, key0, &sm0, 0, 0))
             {
               b0->error = node->errors[SNAT_IN2OUT_ERROR_NO_TRANSLATION];
               next0= SNAT_IN2OUT_NEXT_DROP;