nat: perf improvement - replace branchy code

Use a lookup table instead.

Type: improvement
Signed-off-by: Klement Sekera <ksekera@cisco.com>
Change-Id: Ia8461099828bb8824bf016201f135e6b69c444d1

32 files changed, 401 insertions, 451 deletions

diff --git a/src/plugins/nat/dslite/dslite_ce_decap.c b/src/plugins/nat/dslite/dslite_ce_decap.c
index 56af25129f2..f36a87f8bc1 100644
--- a/src/plugins/nat/dslite/dslite_ce_decap.c
+++ b/src/plugins/nat/dslite/dslite_ce_decap.c
@@ -81,7 +81,7 @@ VLIB_NODE_FN (dslite_ce_decap_node) (vlib_main_t * vm,
 	  ip40 = vlib_buffer_get_current (b0) + sizeof (ip6_header_t);
 	  proto0 = ip_proto_to_nat_proto (ip40->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    {
 	      error0 = DSLITE_ERROR_UNSUPPORTED_PROTOCOL;
 	      next0 = DSLITE_CE_DECAP_NEXT_DROP;
diff --git a/src/plugins/nat/dslite/dslite_ce_encap.c b/src/plugins/nat/dslite/dslite_ce_encap.c
index 74b5bc39fbe..d8d0e400919 100644
--- a/src/plugins/nat/dslite/dslite_ce_encap.c
+++ b/src/plugins/nat/dslite/dslite_ce_encap.c
@@ -67,7 +67,7 @@ VLIB_NODE_FN (dslite_ce_encap_node) (vlib_main_t * vm,
 	  ip40 = vlib_buffer_get_current (b0);
 	  proto0 = ip_proto_to_nat_proto (ip40->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    {
 	      error0 = DSLITE_ERROR_UNSUPPORTED_PROTOCOL;
 	      next0 = DSLITE_CE_ENCAP_NEXT_DROP;
diff --git a/src/plugins/nat/dslite/dslite_in2out.c b/src/plugins/nat/dslite/dslite_in2out.c
index 1d00bb2d7fe..a8204179a58 100644
--- a/src/plugins/nat/dslite/dslite_in2out.c
+++ b/src/plugins/nat/dslite/dslite_in2out.c
@@ -316,7 +316,7 @@ dslite_in2out_node_fn_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
 	  ip40 = vlib_buffer_get_current (b0) + sizeof (ip6_header_t);
 	  proto0 = ip_proto_to_nat_proto (ip40->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    {
 	      error0 = DSLITE_ERROR_UNSUPPORTED_PROTOCOL;
 	      next0 = DSLITE_IN2OUT_NEXT_DROP;
diff --git a/src/plugins/nat/dslite/dslite_out2in.c b/src/plugins/nat/dslite/dslite_out2in.c
index 96cf9188cf6..c2fa767bd7d 100644
--- a/src/plugins/nat/dslite/dslite_out2in.c
+++ b/src/plugins/nat/dslite/dslite_out2in.c
@@ -146,7 +146,7 @@ VLIB_NODE_FN (dslite_out2in_node) (vlib_main_t * vm,
 	  ip40 = vlib_buffer_get_current (b0);
 	  proto0 = ip_proto_to_nat_proto (ip40->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    {
 	      error0 = DSLITE_ERROR_UNSUPPORTED_PROTOCOL;
 	      next0 = DSLITE_OUT2IN_NEXT_DROP;
diff --git a/src/plugins/nat/in2out.c b/src/plugins/nat/in2out.c
index 936cd59e1d1..8f92bae0302 100755
--- a/src/plugins/nat/in2out.c
+++ b/src/plugins/nat/in2out.c
@@ -409,7 +409,7 @@ static_always_inline
   if (!icmp_type_is_error_message
       (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags))
     {
-      key0.protocol = SNAT_PROTOCOL_ICMP;
+      key0.protocol = NAT_PROTOCOL_ICMP;
       key0.addr = ip0->src_address;
       key0.port = vnet_buffer (b)->ip.reass.l4_src_port;	// TODO fixme should this be dst port?
     }
@@ -417,17 +417,17 @@ static_always_inline
     {
       inner_ip0 = (ip4_header_t *) (echo0 + 1);
       l4_header = ip4_next_header (inner_ip0);
-      key0.protocol = ip_proto_to_snat_proto (inner_ip0->protocol);
+      key0.protocol = ip_proto_to_nat_proto (inner_ip0->protocol);
       key0.addr = inner_ip0->dst_address;
       switch (key0.protocol)
 	{
-	case SNAT_PROTOCOL_ICMP:
+	case NAT_PROTOCOL_ICMP:
 	  inner_icmp0 = (icmp46_header_t *) l4_header;
 	  inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 	  key0.port = inner_echo0->identifier;
 	  break;
-	case SNAT_PROTOCOL_UDP:
-	case SNAT_PROTOCOL_TCP:
+	case NAT_PROTOCOL_UDP:
+	case NAT_PROTOCOL_TCP:
 	  key0.port = ((tcp_udp_header_t *) l4_header)->dst_port;
 	  break;
 	default:
@@ -503,7 +503,7 @@ icmp_match_in2out_slow (snat_main_t * sm, vlib_node_runtime_t * node,
       else
 	{
 	  if (PREDICT_FALSE (snat_not_translate (sm, node, sw_if_index0,
-						 ip0, SNAT_PROTOCOL_ICMP,
+						 ip0, NAT_PROTOCOL_ICMP,
 						 rx_fib_index0,
 						 thread_index)))
 	    {
@@ -765,7 +765,7 @@ icmp_in2out (snat_main_t * sm,
 
 	  switch (protocol)
 	    {
-	    case SNAT_PROTOCOL_ICMP:
+	    case NAT_PROTOCOL_ICMP:
 	      inner_icmp0 = (icmp46_header_t *) l4_header;
 	      inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 
@@ -779,8 +779,8 @@ icmp_in2out (snat_main_t * sm,
 				identifier);
 	      icmp0->checksum = ip_csum_fold (sum0);
 	      break;
-	    case SNAT_PROTOCOL_UDP:
-	    case SNAT_PROTOCOL_TCP:
+	    case NAT_PROTOCOL_UDP:
+	    case NAT_PROTOCOL_TCP:
 	      old_id0 = ((tcp_udp_header_t *) l4_header)->dst_port;
 	      new_id0 = sm0.port;
 	      ((tcp_udp_header_t *) l4_header)->dst_port = new_id0;
@@ -975,12 +975,12 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
 	      goto trace00;
 	    }
 
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
 	  /* Next configured feature, probably ip4-lookup */
 	  if (is_slow_path)
 	    {
-	      if (PREDICT_FALSE (proto0 == ~0))
+	      if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 		{
 		  if (nat_in2out_sm_unknown_proto
 		      (sm, b0, ip0, rx_fib_index0))
@@ -993,7 +993,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
 		  goto trace00;
 		}
 
-	      if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	      if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 		{
 		  next0 = icmp_in2out_slow_path
 		    (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0,
@@ -1004,13 +1004,13 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
 	    }
 	  else
 	    {
-	      if (PREDICT_FALSE (proto0 == ~0))
+	      if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 		{
 		  next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
 		  goto trace00;
 		}
 
-	      if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	      if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 		{
 		  next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
 		  goto trace00;
@@ -1046,7 +1046,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
 		       * be able to use dhcp client on the outside interface
 		       */
 		      if (PREDICT_FALSE
-			  (proto0 == SNAT_PROTOCOL_UDP
+			  (proto0 == NAT_PROTOCOL_UDP
 			   && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
 			       clib_host_to_net_u16
 			       (UDP_DST_PORT_dhcp_to_server))
@@ -1096,7 +1096,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
 	  ip0->checksum = ip_csum_fold (sum0);
 
 
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 		{
@@ -1183,12 +1183,12 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
 	      goto trace01;
 	    }
 
-	  proto1 = ip_proto_to_snat_proto (ip1->protocol);
+	  proto1 = ip_proto_to_nat_proto (ip1->protocol);
 
 	  /* Next configured feature, probably ip4-lookup */
 	  if (is_slow_path)
 	    {
-	      if (PREDICT_FALSE (proto1 == ~0))
+	      if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_OTHER))
 		{
 		  if (nat_in2out_sm_unknown_proto
 		      (sm, b1, ip1, rx_fib_index1))
@@ -1201,7 +1201,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
 		  goto trace01;
 		}
 
-	      if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
+	      if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_ICMP))
 		{
 		  next1 = icmp_in2out_slow_path
 		    (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
@@ -1212,13 +1212,13 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
 	    }
 	  else
 	    {
-	      if (PREDICT_FALSE (proto1 == ~0))
+	      if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_OTHER))
 		{
 		  next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
 		  goto trace01;
 		}
 
-	      if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
+	      if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_ICMP))
 		{
 		  next1 = SNAT_IN2OUT_NEXT_SLOW_PATH;
 		  goto trace01;
@@ -1254,7 +1254,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
 		       * be able to use dhcp client on the outside interface
 		       */
 		      if (PREDICT_FALSE
-			  (proto1 == SNAT_PROTOCOL_UDP
+			  (proto1 == NAT_PROTOCOL_UDP
 			   && (vnet_buffer (b1)->ip.reass.l4_dst_port ==
 			       clib_host_to_net_u16
 			       (UDP_DST_PORT_dhcp_to_server))
@@ -1303,7 +1303,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
 				 src_address /* changed member */ );
 	  ip1->checksum = ip_csum_fold (sum1);
 
-	  if (PREDICT_TRUE (proto1 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto1 == NAT_PROTOCOL_TCP))
 	    {
 	      if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 		{
@@ -1426,12 +1426,12 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
 	      goto trace0;
 	    }
 
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
 	  /* Next configured feature, probably ip4-lookup */
 	  if (is_slow_path)
 	    {
-	      if (PREDICT_FALSE (proto0 == ~0))
+	      if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 		{
 		  if (nat_in2out_sm_unknown_proto
 		      (sm, b0, ip0, rx_fib_index0))
@@ -1444,7 +1444,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
 		  goto trace0;
 		}
 
-	      if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	      if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 		{
 		  next0 = icmp_in2out_slow_path
 		    (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
@@ -1455,13 +1455,13 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
 	    }
 	  else
 	    {
-	      if (PREDICT_FALSE (proto0 == ~0))
+	      if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 		{
 		  next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
 		  goto trace0;
 		}
 
-	      if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	      if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 		{
 		  next0 = SNAT_IN2OUT_NEXT_SLOW_PATH;
 		  goto trace0;
@@ -1495,7 +1495,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
 		       * be able to use dhcp client on the outside interface
 		       */
 		      if (PREDICT_FALSE
-			  (proto0 == SNAT_PROTOCOL_UDP
+			  (proto0 == NAT_PROTOCOL_UDP
 			   && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
 			       clib_host_to_net_u16
 			       (UDP_DST_PORT_dhcp_to_server))
@@ -1545,7 +1545,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
 				 src_address /* changed member */ );
 	  ip0->checksum = ip_csum_fold (sum0);
 
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 		{
@@ -1832,12 +1832,12 @@ VLIB_NODE_FN (snat_in2out_fast_node) (vlib_main_t * vm,
 	      goto trace0;
 	    }
 
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    goto trace0;
 
-	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 	    {
 	      next0 = icmp_in2out (sm, b0, ip0, icmp0, sw_if_index0,
 				   rx_fib_index0, node, next0, ~0, 0, 0);
@@ -1873,7 +1873,7 @@ VLIB_NODE_FN (snat_in2out_fast_node) (vlib_main_t * vm,
 	      old_port0 = udp0->src_port;
 	      udp0->src_port = new_port0;
 
-	      if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	      if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 		{
 		  sum0 = tcp0->checksum;
 		  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
@@ -1899,7 +1899,7 @@ VLIB_NODE_FN (snat_in2out_fast_node) (vlib_main_t * vm,
 	    }
 	  else
 	    {
-	      if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	      if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 		{
 		  sum0 = tcp0->checksum;
 		  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
diff --git a/src/plugins/nat/in2out_ed.c b/src/plugins/nat/in2out_ed.c
index 7ad66553fe9..f8682d0f3c2 100644
--- a/src/plugins/nat/in2out_ed.c
+++ b/src/plugins/nat/in2out_ed.c
@@ -101,7 +101,7 @@ nat44_i2o_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg)
 	}
       else
 	{
-	  proto = snat_proto_to_ip_proto (s->in2out.protocol);
+	  proto = nat_proto_to_ip_proto (s->in2out.protocol);
 	  l_port = s->out2in.port;
 	  r_port = s->ext_host_port;
 	}
@@ -197,7 +197,7 @@ snat_random_port (u16 min, u16 max)
 
 static int
 nat_ed_alloc_addr_and_port (snat_main_t * sm, u32 rx_fib_index,
-			    u32 snat_proto, u32 thread_index,
+			    u32 nat_proto, u32 thread_index,
 			    ip4_address_t r_addr, u16 r_port, u8 proto,
 			    u16 port_per_thread, u32 snat_thread_index,
 			    snat_session_t * s,
@@ -215,10 +215,10 @@ nat_ed_alloc_addr_and_port (snat_main_t * sm, u32 rx_fib_index,
   for (i = 0; i < vec_len (sm->addresses); i++)
     {
       a = sm->addresses + i;
-      switch (snat_proto)
+      switch (nat_proto)
 	{
 #define _(N, j, n, unused)                                                    \
-  case SNAT_PROTOCOL_##N:                                                     \
+  case NAT_PROTOCOL_##N:                                                     \
     if (a->fib_index == rx_fib_index)                                         \
       {                                                                       \
         u16 port = snat_random_port (1, port_per_thread);                     \
@@ -250,7 +250,7 @@ nat_ed_alloc_addr_and_port (snat_main_t * sm, u32 rx_fib_index,
       }                                                                       \
     break;
 
-	  foreach_snat_protocol;
+	  foreach_nat_protocol;
 	default:
 	  nat_elog_info ("unknown protocol");
 	  return 1;
@@ -262,9 +262,9 @@ nat_ed_alloc_addr_and_port (snat_main_t * sm, u32 rx_fib_index,
       /* fake fib_index to reuse macro */
       rx_fib_index = ~0;
       a = ga;
-      switch (snat_proto)
+      switch (nat_proto)
 	{
-	  foreach_snat_protocol;
+	  foreach_nat_protocol;
 	default:
 	  nat_elog_info ("unknown protocol");
 	  return 1;
@@ -294,7 +294,7 @@ slow_path_ed (snat_main_t * sm,
   snat_session_key_t key0, key1;
   lb_nat_type_t lb = 0;
   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
-  u32 snat_proto = ip_proto_to_snat_proto (proto);
+  u32 nat_proto = ip_proto_to_nat_proto (proto);
   nat_outside_fib_t *outside_fib;
   fib_node_index_t fei = FIB_NODE_INDEX_INVALID;
   clib_bihash_kv_16_8_t out2in_ed_kv;
@@ -308,7 +308,7 @@ slow_path_ed (snat_main_t * sm,
   };
   nat44_is_idle_session_ctx_t ctx;
 
-  if (PREDICT_TRUE (snat_proto == SNAT_PROTOCOL_TCP))
+  if (PREDICT_TRUE (nat_proto == NAT_PROTOCOL_TCP))
     {
       if (PREDICT_FALSE
 	  (!tcp_flags_is_init
@@ -334,7 +334,7 @@ slow_path_ed (snat_main_t * sm,
 
   key0.addr = l_addr;
   key0.port = l_port;
-  key1.protocol = key0.protocol = snat_proto;
+  key1.protocol = key0.protocol = nat_proto;
   key0.fib_index = rx_fib_index;
   key1.fib_index = sm->outside_fib_index;
 
@@ -376,7 +376,7 @@ slow_path_ed (snat_main_t * sm,
 	}
 
       /* Try to create dynamic translation */
-      if (nat_ed_alloc_addr_and_port (sm, rx_fib_index, snat_proto,
+      if (nat_ed_alloc_addr_and_port (sm, rx_fib_index, nat_proto,
 				      thread_index, r_addr, r_port, proto,
 				      sm->port_per_thread,
 				      tsm->snat_thread_index, s,
@@ -678,7 +678,7 @@ icmp_match_in2out_ed (snat_main_t * sm, vlib_node_runtime_t * node,
       else
 	{
 	  if (PREDICT_FALSE (nat44_ed_not_translate (sm, node, sw_if_index,
-						     ip, SNAT_PROTOCOL_ICMP,
+						     ip, NAT_PROTOCOL_ICMP,
 						     rx_fib_index,
 						     thread_index)))
 	    {
@@ -991,9 +991,9 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
 
 	  udp0 = ip4_next_header (ip0);
 	  tcp0 = (tcp_header_t *) udp0;
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    {
 	      next0 = def_slow;
 	      goto trace0;
@@ -1006,7 +1006,7 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
 		goto trace0;
 	    }
 
-	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 	    {
 	      next0 = def_slow;
 	      goto trace0;
@@ -1073,7 +1073,7 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
 
 	  old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
 
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 		{
@@ -1273,9 +1273,9 @@ nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t * vm,
 	  udp0 = ip4_next_header (ip0);
 	  tcp0 = (tcp_header_t *) udp0;
 	  icmp0 = (icmp46_header_t *) udp0;
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    {
 	      s0 = nat44_ed_in2out_unknown_proto (sm, b0, ip0,
 						  rx_fib_index0,
@@ -1288,7 +1288,7 @@ nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t * vm,
 	      goto trace0;
 	    }
 
-	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 	    {
 	      next0 = icmp_in2out_ed_slow_path
 		(sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0,
@@ -1332,7 +1332,7 @@ nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t * vm,
 		   * be able to use dhcp client on the outside interface
 		   */
 		  if (PREDICT_FALSE
-		      (proto0 == SNAT_PROTOCOL_UDP
+		      (proto0 == NAT_PROTOCOL_UDP
 		       && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
 			   clib_host_to_net_u16 (UDP_DST_PORT_dhcp_to_server))
 		       && ip0->dst_address.as_u32 == 0xffffffff))
@@ -1380,7 +1380,7 @@ nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t * vm,
 
 	  old_port0 = vnet_buffer (b0)->ip.reass.l4_src_port;
 
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 		{
diff --git a/src/plugins/nat/lib/inlines.h b/src/plugins/nat/lib/inlines.h
index f2bd5e08ce6..107944915cd 100644
--- a/src/plugins/nat/lib/inlines.h
+++ b/src/plugins/nat/lib/inlines.h
@@ -13,34 +13,40 @@
  * limitations under the License.
  */
 /**
- * @brief The NAT44 inline functions
+ * @brief Common NAT inline functions
  */
 #ifndef included_nat_inlines_h__
 #define included_nat_inlines_h__
 
-static_always_inline u32
+always_inline nat_protocol_t
 ip_proto_to_nat_proto (u8 ip_proto)
 {
-  u32 nat_proto = ~0;
+  static const nat_protocol_t lookup_table[256] = {
+    [IP_PROTOCOL_TCP] = NAT_PROTOCOL_TCP,
+    [IP_PROTOCOL_UDP] = NAT_PROTOCOL_UDP,
+    [IP_PROTOCOL_ICMP] = NAT_PROTOCOL_ICMP,
+    [IP_PROTOCOL_ICMP6] = NAT_PROTOCOL_ICMP,
+  };
 
-  nat_proto = (ip_proto == IP_PROTOCOL_UDP) ? NAT_PROTOCOL_UDP : nat_proto;
-  nat_proto = (ip_proto == IP_PROTOCOL_TCP) ? NAT_PROTOCOL_TCP : nat_proto;
-  nat_proto = (ip_proto == IP_PROTOCOL_ICMP) ? NAT_PROTOCOL_ICMP : nat_proto;
-  nat_proto = (ip_proto == IP_PROTOCOL_ICMP6) ? NAT_PROTOCOL_ICMP : nat_proto;
-
-  return nat_proto;
+  return lookup_table[ip_proto];
 }
 
 static_always_inline u8
 nat_proto_to_ip_proto (nat_protocol_t nat_proto)
 {
-  u8 ip_proto = ~0;
+  ASSERT (nat_proto <= NAT_PROTOCOL_ICMP);
+
+  static const u8 lookup_table[256] = {
+    [NAT_PROTOCOL_OTHER] = ~0,
+    [NAT_PROTOCOL_TCP] = IP_PROTOCOL_TCP,
+    [NAT_PROTOCOL_UDP] = IP_PROTOCOL_UDP,
+    [NAT_PROTOCOL_ICMP] = IP_PROTOCOL_ICMP,
+  };
 
-  ip_proto = (nat_proto == NAT_PROTOCOL_UDP) ? IP_PROTOCOL_UDP : ip_proto;
-  ip_proto = (nat_proto == NAT_PROTOCOL_TCP) ? IP_PROTOCOL_TCP : ip_proto;
-  ip_proto = (nat_proto == NAT_PROTOCOL_ICMP) ? IP_PROTOCOL_ICMP : ip_proto;
+  ASSERT (NAT_PROTOCOL_OTHER == nat_proto || NAT_PROTOCOL_TCP == nat_proto
+	  || NAT_PROTOCOL_UDP == nat_proto || NAT_PROTOCOL_ICMP == nat_proto);
 
-  return ip_proto;
+  return lookup_table[nat_proto];
 }
 
 static_always_inline u8
diff --git a/src/plugins/nat/lib/lib.h b/src/plugins/nat/lib/lib.h
index 005db81b4a3..bd1c43338e6 100644
--- a/src/plugins/nat/lib/lib.h
+++ b/src/plugins/nat/lib/lib.h
@@ -19,16 +19,11 @@
 #ifndef included_nat_lib_h__
 #define included_nat_lib_h__
 
-#define foreach_nat_error \
-  _(VALUE_EXIST, -1, "Value already exists") \
-  _(NO_SUCH_ENTRY, -2, "No such entry") \
-  _(UNKNOWN_PROTOCOL, -3, "Unknown protocol") \
-  _(OUT_OF_TRANSLATIONS, -4, "Out of translations")
-
-#define foreach_nat_protocol \
-  _(UDP, 0, udp, "udp")       \
-  _(TCP, 1, tcp, "tcp")       \
-  _(ICMP, 2, icmp, "icmp")
+#define foreach_nat_error                      \
+  _ (VALUE_EXIST, -1, "Value already exists")  \
+  _ (NO_SUCH_ENTRY, -2, "No such entry")       \
+  _ (UNKNOWN_PROTOCOL, -3, "Unknown protocol") \
+  _ (OUT_OF_TRANSLATIONS, -4, "Out of translations")
 
 typedef enum
 {
@@ -37,6 +32,12 @@ typedef enum
 #undef _
 } nat_error_t;
 
+#define foreach_nat_protocol   \
+  _ (OTHER, 0, other, "other") \
+  _ (UDP, 1, udp, "udp")       \
+  _ (TCP, 2, tcp, "tcp")       \
+  _ (ICMP, 3, icmp, "icmp")
+
 typedef enum
 {
 #define _(N, i, n, s) NAT_PROTOCOL_##N = i,
diff --git a/src/plugins/nat/nat.c b/src/plugins/nat/nat.c
index 125a969313c..1fb3a7ff397 100755
--- a/src/plugins/nat/nat.c
+++ b/src/plugins/nat/nat.c
@@ -220,7 +220,7 @@ nat_free_session_data (snat_main_t * sm, snat_session_t * s, u32 thread_index,
 	  r_port = s->ext_host_port;
 	  l_addr = &s->in2out.addr;
 	  r_addr = &s->ext_host_addr;
-	  proto = snat_proto_to_ip_proto (s->in2out.protocol);
+	  proto = nat_proto_to_ip_proto (s->in2out.protocol);
 	  make_ed_kv (l_addr, r_addr, proto, fib_index, l_port, r_port, ~0ULL,
 		      &ed_kv);
 	}
@@ -246,7 +246,7 @@ nat_free_session_data (snat_main_t * sm, snat_session_t * s, u32 thread_index,
 	}
       else
 	{
-	  proto = snat_proto_to_ip_proto (s->in2out.protocol);
+	  proto = nat_proto_to_ip_proto (s->in2out.protocol);
 	  l_port = s->out2in.port;
 	  r_port = s->ext_host_port;
 	}
@@ -370,7 +370,7 @@ nat44_free_session_data (snat_main_t * sm, snat_session_t * s,
 	}
       else
 	{
-	  proto = snat_proto_to_ip_proto (s->in2out.protocol);
+	  proto = nat_proto_to_ip_proto (s->in2out.protocol);
 	  l_port = s->in2out.port;
 	  r_port = s->ext_host_port;
 	}
@@ -402,7 +402,7 @@ nat44_free_session_data (snat_main_t * sm, snat_session_t * s,
     }
   else
     {
-      proto = snat_proto_to_ip_proto (s->in2out.protocol);
+      proto = nat_proto_to_ip_proto (s->in2out.protocol);
       l_port = s->out2in.port;
       r_port = s->ext_host_port;
     }
@@ -728,7 +728,7 @@ snat_add_address (snat_main_t * sm, ip4_address_t * addr, u32 vrf_id,
   ap->busy_##n##_ports = 0; \
   ap->busy_##n##_ports_per_thread = 0;\
   vec_validate_init_empty (ap->busy_##n##_ports_per_thread, tm->n_vlib_mains - 1, 0);
-  foreach_snat_protocol
+  foreach_nat_protocol
 #undef _
     if (twice_nat)
     return 0;
@@ -782,7 +782,7 @@ snat_add_static_mapping_when_resolved (snat_main_t * sm,
 				       u32 sw_if_index,
 				       u16 e_port,
 				       u32 vrf_id,
-				       snat_protocol_t proto,
+				       nat_protocol_t proto,
 				       int addr_only, int is_add, u8 * tag,
 				       int twice_nat, int out2in_only,
 				       int identity_nat)
@@ -920,7 +920,7 @@ snat_ed_static_mapping_del_sessions (snat_main_t * sm,
 int
 snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
 			 u16 l_port, u16 e_port, u32 vrf_id, int addr_only,
-			 u32 sw_if_index, snat_protocol_t proto, int is_add,
+			 u32 sw_if_index, nat_protocol_t proto, int is_add,
 			 twice_nat_type_t twice_nat, u8 out2in_only, u8 * tag,
 			 u8 identity_nat)
 {
@@ -1101,7 +1101,7 @@ snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
 		  switch (proto)
 		    {
 #define _(N, j, n, s) \
-                    case SNAT_PROTOCOL_##N: \
+                    case NAT_PROTOCOL_##N: \
                       if (a->busy_##n##_port_refcounts[e_port]) \
                         return VNET_API_ERROR_INVALID_VALUE; \
                       ++a->busy_##n##_port_refcounts[e_port]; \
@@ -1111,7 +1111,7 @@ snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
                           a->busy_##n##_ports_per_thread[get_thread_idx_by_port(e_port)]++; \
                         } \
                       break;
-		      foreach_snat_protocol
+		      foreach_nat_protocol
 #undef _
 		    default:
 		      nat_elog_info ("unknown protocol");
@@ -1285,7 +1285,7 @@ snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
 		  switch (proto)
 		    {
 #define _(N, j, n, s) \
-                    case SNAT_PROTOCOL_##N: \
+                    case NAT_PROTOCOL_##N: \
                       --a->busy_##n##_port_refcounts[e_port]; \
                       if (e_port > 1024) \
                         { \
@@ -1293,7 +1293,7 @@ snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
                           a->busy_##n##_ports_per_thread[get_thread_idx_by_port(e_port)]--; \
                         } \
                       break;
-		      foreach_snat_protocol
+		      foreach_nat_protocol
 #undef _
 		    default:
 		      nat_elog_info ("unknown protocol");
@@ -1382,7 +1382,7 @@ snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
 
 int
 nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
-				 snat_protocol_t proto,
+				 nat_protocol_t proto,
 				 nat44_lb_addr_port_t * locals, u8 is_add,
 				 twice_nat_type_t twice_nat, u8 out2in_only,
 				 u8 * tag, u32 affinity)
@@ -1432,7 +1432,7 @@ nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
 		  switch (proto)
 		    {
 #define _(N, j, n, s) \
-                    case SNAT_PROTOCOL_##N: \
+                    case NAT_PROTOCOL_##N: \
                       if (a->busy_##n##_port_refcounts[e_port]) \
                         return VNET_API_ERROR_INVALID_VALUE; \
                       ++a->busy_##n##_port_refcounts[e_port]; \
@@ -1442,7 +1442,7 @@ nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
                           a->busy_##n##_ports_per_thread[get_thread_idx_by_port(e_port)]++; \
                         } \
                       break;
-		      foreach_snat_protocol
+		      foreach_nat_protocol
 #undef _
 		    default:
 		      nat_elog_info ("unknown protocol");
@@ -1548,7 +1548,7 @@ nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
 		  switch (proto)
 		    {
 #define _(N, j, n, s) \
-                    case SNAT_PROTOCOL_##N: \
+                    case NAT_PROTOCOL_##N: \
                       --a->busy_##n##_port_refcounts[e_port]; \
                       if (e_port > 1024) \
                         { \
@@ -1556,7 +1556,7 @@ nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
                           a->busy_##n##_ports_per_thread[get_thread_idx_by_port(e_port)]--; \
                         } \
                       break;
-		      foreach_snat_protocol
+		      foreach_nat_protocol
 #undef _
 		    default:
 		      nat_elog_info ("unknown protocol");
@@ -1636,7 +1636,7 @@ nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
 int
 nat44_lb_static_mapping_add_del_local (ip4_address_t e_addr, u16 e_port,
 				       ip4_address_t l_addr, u16 l_port,
-				       snat_protocol_t proto, u32 vrf_id,
+				       nat_protocol_t proto, u32 vrf_id,
 				       u8 probability, u8 is_add)
 {
   snat_main_t *sm = &snat_main;
@@ -1883,7 +1883,7 @@ snat_del_address (snat_main_t * sm, ip4_address_t addr, u8 delete_sm,
 
 #define _(N, i, n, s) \
   vec_free (a->busy_##n##_ports_per_thread);
-  foreach_snat_protocol
+  foreach_nat_protocol
 #undef _
     if (twice_nat)
     {
@@ -2746,13 +2746,13 @@ snat_free_outside_address_and_port (snat_address_t * addresses,
   switch (k->protocol)
     {
 #define _(N, i, n, s) \
-    case SNAT_PROTOCOL_##N: \
+    case NAT_PROTOCOL_##N: \
       ASSERT (a->busy_##n##_port_refcounts[port_host_byte_order] >= 1); \
       --a->busy_##n##_port_refcounts[port_host_byte_order]; \
       a->busy_##n##_ports--; \
       a->busy_##n##_ports_per_thread[thread_index]--; \
       break;
-      foreach_snat_protocol
+      foreach_nat_protocol
 #undef _
     default:
       nat_elog_info ("unknown protocol");
@@ -2778,14 +2778,14 @@ nat_set_outside_address_and_port (snat_address_t * addresses,
       switch (k->protocol)
 	{
 #define _(N, j, n, s) \
-        case SNAT_PROTOCOL_##N: \
+        case NAT_PROTOCOL_##N: \
           if (a->busy_##n##_port_refcounts[port_host_byte_order]) \
             return VNET_API_ERROR_INSTANCE_IN_USE; \
 	  ++a->busy_##n##_port_refcounts[port_host_byte_order]; \
           a->busy_##n##_ports_per_thread[thread_index]++; \
           a->busy_##n##_ports++; \
           return 0;
-	  foreach_snat_protocol
+	  foreach_nat_protocol
 #undef _
 	default:
 	  nat_elog_info ("unknown protocol");
@@ -2986,7 +2986,7 @@ nat_alloc_addr_and_port_default (snat_address_t * addresses,
       switch (k->protocol)
 	{
 #define _(N, j, n, s) \
-        case SNAT_PROTOCOL_##N: \
+        case NAT_PROTOCOL_##N: \
           if (a->busy_##n##_ports_per_thread[thread_index] < port_per_thread) \
             { \
               if (a->fib_index == fib_index) \
@@ -3012,7 +3012,7 @@ nat_alloc_addr_and_port_default (snat_address_t * addresses,
                 } \
             } \
           break;
-	  foreach_snat_protocol
+	  foreach_nat_protocol
 #undef _
 	default:
 	  nat_elog_info ("unknown protocol");
@@ -3027,7 +3027,7 @@ nat_alloc_addr_and_port_default (snat_address_t * addresses,
       switch (k->protocol)
 	{
 #define _(N, j, n, s) \
-        case SNAT_PROTOCOL_##N: \
+        case NAT_PROTOCOL_##N: \
           while (1) \
             { \
               portnum = (port_per_thread * \
@@ -3043,7 +3043,7 @@ nat_alloc_addr_and_port_default (snat_address_t * addresses,
               return 0; \
             }
 	  break;
-	  foreach_snat_protocol
+	  foreach_nat_protocol
 #undef _
 	default:
 	  nat_elog_info ("unknown protocol");
@@ -3075,7 +3075,7 @@ nat_alloc_addr_and_port_mape (snat_address_t * addresses,
   switch (k->protocol)
     {
 #define _(N, i, n, s) \
-    case SNAT_PROTOCOL_##N: \
+    case NAT_PROTOCOL_##N: \
       if (a->busy_##n##_ports < ports) \
         { \
           while (1) \
@@ -3093,7 +3093,7 @@ nat_alloc_addr_and_port_mape (snat_address_t * addresses,
             } \
         } \
       break;
-      foreach_snat_protocol
+      foreach_nat_protocol
 #undef _
     default:
       nat_elog_info ("unknown protocol");
@@ -3125,7 +3125,7 @@ nat_alloc_addr_and_port_range (snat_address_t * addresses,
   switch (k->protocol)
     {
 #define _(N, i, n, s) \
-    case SNAT_PROTOCOL_##N: \
+    case NAT_PROTOCOL_##N: \
       if (a->busy_##n##_ports < ports) \
         { \
           while (1) \
@@ -3141,7 +3141,7 @@ nat_alloc_addr_and_port_range (snat_address_t * addresses,
             } \
         } \
       break;
-      foreach_snat_protocol
+      foreach_nat_protocol
 #undef _
     default:
       nat_elog_info ("unknown protocol");
@@ -3287,12 +3287,12 @@ snat_get_worker_out2in_cb (vlib_buffer_t * b, ip4_header_t * ip0,
 	}
     }
 
-  proto = ip_proto_to_snat_proto (ip0->protocol);
+  proto = ip_proto_to_nat_proto (ip0->protocol);
   udp = ip4_next_header (ip0);
   port = udp->dst_port;
 
   /* unknown protocol */
-  if (PREDICT_FALSE (proto == ~0))
+  if (PREDICT_FALSE (proto == NAT_PROTOCOL_OTHER))
     {
       /* use current thread */
       return vlib_get_thread_index ();
@@ -3309,17 +3309,17 @@ snat_get_worker_out2in_cb (vlib_buffer_t * b, ip4_header_t * ip0,
 	{
 	  /* if error message, then it's not fragmented and we can access it */
 	  ip4_header_t *inner_ip = (ip4_header_t *) (echo + 1);
-	  proto = ip_proto_to_snat_proto (inner_ip->protocol);
+	  proto = ip_proto_to_nat_proto (inner_ip->protocol);
 	  void *l4_header = ip4_next_header (inner_ip);
 	  switch (proto)
 	    {
-	    case SNAT_PROTOCOL_ICMP:
+	    case NAT_PROTOCOL_ICMP:
 	      icmp = (icmp46_header_t *) l4_header;
 	      echo = (icmp_echo_header_t *) (icmp + 1);
 	      port = echo->identifier;
 	      break;
-	    case SNAT_PROTOCOL_UDP:
-	    case SNAT_PROTOCOL_TCP:
+	    case NAT_PROTOCOL_UDP:
+	    case NAT_PROTOCOL_TCP:
 	      port = ((tcp_udp_header_t *) l4_header)->src_port;
 	      break;
 	    default:
@@ -3470,9 +3470,9 @@ nat44_ed_get_worker_out2in_cb (vlib_buffer_t * b, ip4_header_t * ip,
   snat_static_mapping_t *m;
   u32 hash;
 
-  proto = ip_proto_to_snat_proto (ip->protocol);
+  proto = ip_proto_to_nat_proto (ip->protocol);
 
-  if (PREDICT_TRUE (proto == SNAT_PROTOCOL_UDP || proto == SNAT_PROTOCOL_TCP))
+  if (PREDICT_TRUE (proto == NAT_PROTOCOL_UDP || proto == NAT_PROTOCOL_TCP))
     {
       udp = ip4_next_header (ip);
 
@@ -3496,7 +3496,7 @@ nat44_ed_get_worker_out2in_cb (vlib_buffer_t * b, ip4_header_t * ip,
           }
         /* *INDENT-ON* */
     }
-  else if (proto == SNAT_PROTOCOL_ICMP)
+  else if (proto == NAT_PROTOCOL_ICMP)
     {
       if (!get_icmp_o2i_ed_key (b, ip, rx_fib_index, ~0ULL, 0, 0, 0, &kv16))
 	{
@@ -3533,7 +3533,7 @@ nat44_ed_get_worker_out2in_cb (vlib_buffer_t * b, ip4_header_t * ip,
     }
 
   /* unknown protocol */
-  if (PREDICT_FALSE (proto == ~0))
+  if (PREDICT_FALSE (proto == NAT_PROTOCOL_OTHER))
     {
       /* use current thread */
       next_worker_index = vlib_get_thread_index ();
@@ -3554,17 +3554,17 @@ nat44_ed_get_worker_out2in_cb (vlib_buffer_t * b, ip4_header_t * ip,
 	{
 	  /* if error message, then it's not fragmented and we can access it */
 	  ip4_header_t *inner_ip = (ip4_header_t *) (echo + 1);
-	  proto = ip_proto_to_snat_proto (inner_ip->protocol);
+	  proto = ip_proto_to_nat_proto (inner_ip->protocol);
 	  void *l4_header = ip4_next_header (inner_ip);
 	  switch (proto)
 	    {
-	    case SNAT_PROTOCOL_ICMP:
+	    case NAT_PROTOCOL_ICMP:
 	      icmp = (icmp46_header_t *) l4_header;
 	      echo = (icmp_echo_header_t *) (icmp + 1);
 	      port = echo->identifier;
 	      break;
-	    case SNAT_PROTOCOL_UDP:
-	    case SNAT_PROTOCOL_TCP:
+	    case NAT_PROTOCOL_UDP:
+	    case NAT_PROTOCOL_TCP:
 	      port = ((tcp_udp_header_t *) l4_header)->src_port;
 	      break;
 	    default:
@@ -3855,12 +3855,12 @@ nat_ha_sadd_ed_cb (ip4_address_t * in_addr, u16 in_port,
   s->in2out = key;
 
   make_ed_kv (in_addr, &s->ext_host_nat_addr,
-	      snat_proto_to_ip_proto (proto), fib_index, in_port,
+	      nat_proto_to_ip_proto (proto), fib_index, in_port,
 	      s->ext_host_nat_port, s - tsm->sessions, &kv);
   if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &kv, 1))
     nat_elog_warn ("in2out key add failed");
 
-  make_ed_kv (out_addr, eh_addr, snat_proto_to_ip_proto (proto),
+  make_ed_kv (out_addr, eh_addr, nat_proto_to_ip_proto (proto),
 	      s->out2in.fib_index, out_port, eh_port, s - tsm->sessions, &kv);
   if (clib_bihash_add_del_16_8 (&tsm->out2in_ed, &kv, 1))
     nat_elog_warn ("out2in key add failed");
@@ -4427,7 +4427,7 @@ snat_add_interface_address (snat_main_t * sm, u32 sw_if_index, int is_del,
 
 int
 nat44_del_session (snat_main_t * sm, ip4_address_t * addr, u16 port,
-		   snat_protocol_t proto, u32 vrf_id, int is_in)
+		   nat_protocol_t proto, u32 vrf_id, int is_in)
 {
   snat_main_per_thread_data_t *tsm;
   clib_bihash_kv_8_8_t kv, value;
diff --git a/src/plugins/nat/nat.h b/src/plugins/nat/nat.h
index 33af754fc85..e4f7a06ead8 100644
--- a/src/plugins/nat/nat.h
+++ b/src/plugins/nat/nat.h
@@ -33,6 +33,8 @@
 #include <vlibapi/api.h>
 #include <vlib/log.h>
 #include <vppinfra/bihash_16_8.h>
+#include <nat/lib/lib.h>
+#include <nat/lib/inlines.h>
 
 /* default session timeouts */
 #define SNAT_UDP_TIMEOUT 300
@@ -141,21 +143,6 @@ typedef enum
 #undef _
 } nat_addr_and_port_alloc_alg_t;
 
-
-/* Supported L4 protocols */
-#define foreach_snat_protocol \
-  _(UDP, 0, udp, "udp")       \
-  _(TCP, 1, tcp, "tcp")       \
-  _(ICMP, 2, icmp, "icmp")
-
-typedef enum
-{
-#define _(N, i, n, s) SNAT_PROTOCOL_##N = i,
-  foreach_snat_protocol
-#undef _
-} snat_protocol_t;
-
-
 /* Session state */
 #define foreach_snat_session_state          \
   _(0, UNKNOWN, "unknown")                 \
@@ -329,7 +316,7 @@ typedef struct
   u16 busy_##n##_ports; \
   u16 * busy_##n##_ports_per_thread; \
   u32 busy_##n##_port_refcounts[65535];
-  foreach_snat_protocol
+  foreach_nat_protocol
 #undef _
 /* *INDENT-ON* */
 } snat_address_t;
@@ -420,7 +407,7 @@ typedef struct
   u32 vrf_id;
   u32 fib_index;
   /* protocol */
-  snat_protocol_t proto;
+  nat_protocol_t proto;
   /* 0 = disabled, otherwise client IP affinity sticky time in seconds */
   u32 affinity;
   /* worker threads used by backends/local host */
@@ -448,7 +435,7 @@ typedef struct
   u16 e_port;
   u32 sw_if_index;
   u32 vrf_id;
-  snat_protocol_t proto;
+  nat_protocol_t proto;
   u32 flags;
   int addr_only;
   int twice_nat;
@@ -723,10 +710,10 @@ format_function_t format_snat_session;
 format_function_t format_det_map_ses;
 format_function_t format_snat_key;
 format_function_t format_static_mapping_key;
-format_function_t format_snat_protocol;
+format_function_t format_nat_protocol;
 format_function_t format_nat_addr_and_port_alloc_alg;
 /* unformat functions */
-unformat_function_t unformat_snat_protocol;
+unformat_function_t unformat_nat_protocol;
 
 /** \brief Check if SNAT session is created from static mapping.
     @param s SNAT session
@@ -1144,7 +1131,7 @@ void nat44_add_del_address_dpo (ip4_address_t addr, u8 is_add);
 int snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
 			     u16 l_port, u16 e_port, u32 vrf_id,
 			     int addr_only, u32 sw_if_index,
-			     snat_protocol_t proto, int is_add,
+			     nat_protocol_t proto, int is_add,
 			     twice_nat_type_t twice_nat, u8 out2in_only,
 			     u8 * tag, u8 identity_nat);
 
@@ -1164,14 +1151,14 @@ int snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
  * @return 0 on success, non-zero value otherwise
  */
 int nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
-				     snat_protocol_t proto,
+				     nat_protocol_t proto,
 				     nat44_lb_addr_port_t * locals, u8 is_add,
 				     twice_nat_type_t twice_nat,
 				     u8 out2in_only, u8 * tag, u32 affinity);
 
 int nat44_lb_static_mapping_add_del_local (ip4_address_t e_addr, u16 e_port,
 					   ip4_address_t l_addr, u16 l_port,
-					   snat_protocol_t proto, u32 vrf_id,
+					   nat_protocol_t proto, u32 vrf_id,
 					   u8 probability, u8 is_add);
 
 clib_error_t *snat_api_init (vlib_main_t * vm, snat_main_t * sm);
@@ -1232,7 +1219,7 @@ int snat_add_interface_address (snat_main_t * sm, u32 sw_if_index, int is_del,
  * @return 0 on success, non-zero value otherwise
  */
 int nat44_del_session (snat_main_t * sm, ip4_address_t * addr, u16 port,
-		       snat_protocol_t proto, u32 vrf_id, int is_in);
+		       nat_protocol_t proto, u32 vrf_id, int is_in);
 
 /**
  * @brief Delete NAT44 endpoint-dependent session
diff --git a/src/plugins/nat/nat44_classify.c b/src/plugins/nat/nat44_classify.c
index b4645dc42b9..9adef3ba64a 100644
--- a/src/plugins/nat/nat44_classify.c
+++ b/src/plugins/nat/nat44_classify.c
@@ -147,7 +147,7 @@ nat44_classify_node_fn_inline (vlib_main_t * vm,
 		}
 	      m_key0.port =
 		clib_net_to_host_u16 (vnet_buffer (b0)->ip.reass.l4_dst_port);
-	      m_key0.protocol = ip_proto_to_snat_proto (ip0->protocol);
+	      m_key0.protocol = ip_proto_to_nat_proto (ip0->protocol);
 	      kv0.key = m_key0.as_u64;
 	      if (!clib_bihash_search_8_8
 		  (&sm->static_mapping_by_external, &kv0, &value0))
@@ -407,7 +407,7 @@ nat44_ed_classify_node_fn_inline (vlib_main_t * vm,
 		}
 	      m_key0.port =
 		clib_net_to_host_u16 (vnet_buffer (b0)->ip.reass.l4_dst_port);
-	      m_key0.protocol = ip_proto_to_snat_proto (ip0->protocol);
+	      m_key0.protocol = ip_proto_to_nat_proto (ip0->protocol);
 	      kv0.key = m_key0.as_u64;
 	      if (!clib_bihash_search_8_8
 		  (&sm->static_mapping_by_external, &kv0, &value0))
diff --git a/src/plugins/nat/nat44_cli.c b/src/plugins/nat/nat44_cli.c
index f613af0733c..8c800d5c373 100644
--- a/src/plugins/nat/nat44_cli.c
+++ b/src/plugins/nat/nat44_cli.c
@@ -681,10 +681,10 @@ nat44_show_summary_command_fn (vlib_main_t * vm, unformat_input_t * input,
 
             switch (s->in2out.protocol)
               {
-              case SNAT_PROTOCOL_ICMP:
+              case NAT_PROTOCOL_ICMP:
                 icmp_sessions++;
                 break;
-              case SNAT_PROTOCOL_TCP:
+              case NAT_PROTOCOL_TCP:
                 tcp_sessions++;
                 if (s->state)
                   {
@@ -704,7 +704,7 @@ nat44_show_summary_command_fn (vlib_main_t * vm, unformat_input_t * input,
                 else
                   established++;
                 break;
-              case SNAT_PROTOCOL_UDP:
+              case NAT_PROTOCOL_UDP:
               default:
                 udp_sessions++;
                 break;
@@ -727,10 +727,10 @@ nat44_show_summary_command_fn (vlib_main_t * vm, unformat_input_t * input,
 
         switch (s->in2out.protocol)
           {
-          case SNAT_PROTOCOL_ICMP:
+          case NAT_PROTOCOL_ICMP:
             icmp_sessions++;
             break;
-          case SNAT_PROTOCOL_TCP:
+          case NAT_PROTOCOL_TCP:
             tcp_sessions++;
             if (s->state)
               {
@@ -750,7 +750,7 @@ nat44_show_summary_command_fn (vlib_main_t * vm, unformat_input_t * input,
             else
               established++;
             break;
-          case SNAT_PROTOCOL_UDP:
+          case NAT_PROTOCOL_UDP:
           default:
             udp_sessions++;
             break;
@@ -796,7 +796,7 @@ nat44_show_addresses_command_fn (vlib_main_t * vm, unformat_input_t * input,
         vlib_cli_output (vm, "  tenant VRF independent");
     #define _(N, i, n, s) \
       vlib_cli_output (vm, "  %d busy %s ports", ap->busy_##n##_ports, s);
-      foreach_snat_protocol
+      foreach_nat_protocol
     #undef _
     }
   vlib_cli_output (vm, "NAT44 twice-nat pool addresses:");
@@ -810,7 +810,7 @@ nat44_show_addresses_command_fn (vlib_main_t * vm, unformat_input_t * input,
         vlib_cli_output (vm, "  tenant VRF independent");
     #define _(N, i, n, s) \
       vlib_cli_output (vm, "  %d busy %s ports", ap->busy_##n##_ports, s);
-      foreach_snat_protocol
+      foreach_nat_protocol
     #undef _
     }
   /* *INDENT-ON* */
@@ -975,7 +975,7 @@ add_static_mapping_command_fn (vlib_main_t * vm,
   u32 sw_if_index = ~0;
   vnet_main_t *vnm = vnet_get_main ();
   int rv;
-  snat_protocol_t proto = ~0;
+  nat_protocol_t proto = NAT_PROTOCOL_OTHER;
   u8 proto_set = 0;
   twice_nat_type_t twice_nat = TWICE_NAT_DISABLED;
   u8 out2in_only = 0;
@@ -1011,7 +1011,7 @@ add_static_mapping_command_fn (vlib_main_t * vm,
 	;
       else if (unformat (line_input, "vrf %u", &vrf_id))
 	;
-      else if (unformat (line_input, "%U", unformat_snat_protocol, &proto))
+      else if (unformat (line_input, "%U", unformat_nat_protocol, &proto))
 	proto_set = 1;
       else if (unformat (line_input, "twice-nat"))
 	twice_nat = TWICE_NAT;
@@ -1092,7 +1092,7 @@ add_identity_mapping_command_fn (vlib_main_t * vm,
   u32 sw_if_index = ~0;
   vnet_main_t *vnm = vnet_get_main ();
   int rv;
-  snat_protocol_t proto;
+  nat_protocol_t proto;
 
   if (sm->deterministic)
     return clib_error_return (0, UNSUPPORTED_IN_DET_MODE_STR);
@@ -1112,7 +1112,7 @@ add_identity_mapping_command_fn (vlib_main_t * vm,
 	;
       else if (unformat (line_input, "vrf %u", &vrf_id))
 	;
-      else if (unformat (line_input, "%U %u", unformat_snat_protocol, &proto,
+      else if (unformat (line_input, "%U %u", unformat_nat_protocol, &proto,
 			 &port))
 	addr_only = 0;
       else if (unformat (line_input, "del"))
@@ -1168,7 +1168,7 @@ add_lb_static_mapping_command_fn (vlib_main_t * vm,
   u32 l_port = 0, e_port = 0, vrf_id = 0, probability = 0, affinity = 0;
   int is_add = 1;
   int rv;
-  snat_protocol_t proto;
+  nat_protocol_t proto;
   u8 proto_set = 0;
   nat44_lb_addr_port_t *locals = 0, local;
   twice_nat_type_t twice_nat = TWICE_NAT_DISABLED;
@@ -1206,7 +1206,7 @@ add_lb_static_mapping_command_fn (vlib_main_t * vm,
       else if (unformat (line_input, "external %U:%u", unformat_ip4_address,
 			 &e_addr, &e_port))
 	;
-      else if (unformat (line_input, "protocol %U", unformat_snat_protocol,
+      else if (unformat (line_input, "protocol %U", unformat_nat_protocol,
 			 &proto))
 	proto_set = 1;
       else if (unformat (line_input, "twice-nat"))
@@ -1283,7 +1283,7 @@ add_lb_backend_command_fn (vlib_main_t * vm,
   u32 l_port = 0, e_port = 0, vrf_id = 0, probability = 0;
   int is_add = 1;
   int rv;
-  snat_protocol_t proto;
+  nat_protocol_t proto;
   u8 proto_set = 0;
 
   if (sm->deterministic)
@@ -1305,7 +1305,7 @@ add_lb_backend_command_fn (vlib_main_t * vm,
       else if (unformat (line_input, "external %U:%u", unformat_ip4_address,
 			 &e_addr, &e_port))
 	;
-      else if (unformat (line_input, "protocol %U", unformat_snat_protocol,
+      else if (unformat (line_input, "protocol %U", unformat_nat_protocol,
 			 &proto))
 	proto_set = 1;
       else if (unformat (line_input, "del"))
@@ -1657,7 +1657,7 @@ nat44_del_session_command_fn (vlib_main_t * vm,
   clib_error_t *error = 0;
   ip4_address_t addr, eh_addr;
   u32 port = 0, eh_port = 0, vrf_id = sm->outside_vrf_id;
-  snat_protocol_t proto;
+  nat_protocol_t proto;
   int rv;
 
   if (sm->deterministic)
@@ -1671,7 +1671,7 @@ nat44_del_session_command_fn (vlib_main_t * vm,
     {
       if (unformat
 	  (line_input, "%U:%u %U", unformat_ip4_address, &addr, &port,
-	   unformat_snat_protocol, &proto))
+	   unformat_nat_protocol, &proto))
 	;
       else if (unformat (line_input, "in"))
 	{
@@ -1701,7 +1701,7 @@ nat44_del_session_command_fn (vlib_main_t * vm,
   if (is_ed)
     rv =
       nat44_del_ed_session (sm, &addr, port, &eh_addr, eh_port,
-			    snat_proto_to_ip_proto (proto), vrf_id, is_in);
+			    nat_proto_to_ip_proto (proto), vrf_id, is_in);
   else
     rv = nat44_del_session (sm, &addr, port, proto, vrf_id, is_in);
 
diff --git a/src/plugins/nat/nat44_hairpinning.c b/src/plugins/nat/nat44_hairpinning.c
index bdf9e3ce813..d109bb88dea 100644
--- a/src/plugins/nat/nat44_hairpinning.c
+++ b/src/plugins/nat/nat44_hairpinning.c
@@ -161,7 +161,7 @@ snat_hairpinning (snat_main_t * sm,
       old_dst_port0 = tcp0->dst;
       if (PREDICT_TRUE (new_dst_port0 != old_dst_port0))
 	{
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      tcp0->dst = new_dst_port0;
 	      sum0 = tcp0->checksum;
@@ -179,7 +179,7 @@ snat_hairpinning (snat_main_t * sm,
 	}
       else
 	{
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      sum0 = tcp0->checksum;
 	      sum0 = ip_csum_update (sum0, old_dst_addr0, new_dst_addr0,
@@ -218,9 +218,9 @@ snat_icmp_hairpinning (snat_main_t * sm,
 
       inner_ip0 = (ip4_header_t *) ((icmp_echo_header_t *) (icmp0 + 1) + 1);
       l4_header = ip4_next_header (inner_ip0);
-      u32 protocol = ip_proto_to_snat_proto (inner_ip0->protocol);
+      u32 protocol = ip_proto_to_nat_proto (inner_ip0->protocol);
 
-      if (protocol != SNAT_PROTOCOL_TCP && protocol != SNAT_PROTOCOL_UDP)
+      if (protocol != NAT_PROTOCOL_TCP && protocol != NAT_PROTOCOL_UDP)
 	return 1;
 
       if (is_ed)
@@ -298,7 +298,7 @@ snat_icmp_hairpinning (snat_main_t * sm,
 	      u16 icmp_id0 = echo0->identifier;
 	      key0.addr = ip0->dst_address;
 	      key0.port = icmp_id0;
-	      key0.protocol = SNAT_PROTOCOL_ICMP;
+	      key0.protocol = NAT_PROTOCOL_ICMP;
 	      key0.fib_index = sm->outside_fib_index;
 	      kv0.key = key0.as_u64;
 	      if (sm->num_workers > 1)
@@ -473,7 +473,7 @@ nat44_hairpinning_fn_inline (vlib_main_t * vm,
 	  udp0 = ip4_next_header (ip0);
 	  tcp0 = (tcp_header_t *) udp0;
 
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
 	  vnet_get_config_data (&cm->config_main, &b0->current_config_index,
 				&next0, 0);
@@ -584,19 +584,19 @@ snat_hairpin_dst_fn_inline (vlib_main_t * vm,
 	  next0 = NAT_HAIRPIN_NEXT_LOOKUP;
 	  ip0 = vlib_buffer_get_current (b0);
 
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
 	  vnet_buffer (b0)->snat.flags = 0;
 	  if (PREDICT_FALSE (is_hairpinning (sm, &ip0->dst_address)))
 	    {
-	      if (proto0 == SNAT_PROTOCOL_TCP || proto0 == SNAT_PROTOCOL_UDP)
+	      if (proto0 == NAT_PROTOCOL_TCP || proto0 == NAT_PROTOCOL_UDP)
 		{
 		  udp_header_t *udp0 = ip4_next_header (ip0);
 		  tcp_header_t *tcp0 = (tcp_header_t *) udp0;
 
 		  snat_hairpinning (sm, b0, ip0, udp0, tcp0, proto0, is_ed);
 		}
-	      else if (proto0 == SNAT_PROTOCOL_ICMP)
+	      else if (proto0 == NAT_PROTOCOL_ICMP)
 		{
 		  icmp46_header_t *icmp0 = ip4_next_header (ip0);
 
diff --git a/src/plugins/nat/nat64.c b/src/plugins/nat/nat64.c
index abf59a341f4..6c5bfc15196 100644
--- a/src/plugins/nat/nat64.c
+++ b/src/plugins/nat/nat64.c
@@ -133,12 +133,12 @@ nat64_get_worker_out2in (vlib_buffer_t * b, ip4_header_t * ip)
   u16 port;
   u32 proto;
 
-  proto = ip_proto_to_snat_proto (ip->protocol);
+  proto = ip_proto_to_nat_proto (ip->protocol);
   udp = ip4_next_header (ip);
   port = udp->dst_port;
 
   /* unknown protocol */
-  if (PREDICT_FALSE (proto == ~0))
+  if (PREDICT_FALSE (proto == NAT_PROTOCOL_OTHER))
     {
       nat64_db_t *db;
       ip46_address_t daddr;
@@ -170,17 +170,17 @@ nat64_get_worker_out2in (vlib_buffer_t * b, ip4_header_t * ip)
 	{
 	  /* if error message, then it's not fragmented and we can access it */
 	  ip4_header_t *inner_ip = (ip4_header_t *) (echo + 1);
-	  proto = ip_proto_to_snat_proto (inner_ip->protocol);
+	  proto = ip_proto_to_nat_proto (inner_ip->protocol);
 	  void *l4_header = ip4_next_header (inner_ip);
 	  switch (proto)
 	    {
-	    case SNAT_PROTOCOL_ICMP:
+	    case NAT_PROTOCOL_ICMP:
 	      icmp = (icmp46_header_t *) l4_header;
 	      echo = (icmp_echo_header_t *) (icmp + 1);
 	      port = echo->identifier;
 	      break;
-	    case SNAT_PROTOCOL_UDP:
-	    case SNAT_PROTOCOL_TCP:
+	    case NAT_PROTOCOL_UDP:
+	    case NAT_PROTOCOL_TCP:
 	      port = ((tcp_udp_header_t *) l4_header)->src_port;
 	      break;
 	    default:
@@ -314,7 +314,7 @@ nat64_add_del_pool_addr (u32 thread_index,
       clib_memset (a->busy_##n##_port_refcounts, 0, sizeof(a->busy_##n##_port_refcounts)); \
       a->busy_##n##_ports = 0; \
       vec_validate_init_empty (a->busy_##n##_ports_per_thread, tm->n_vlib_mains - 1, 0);
-      foreach_snat_protocol
+      foreach_nat_protocol
 #undef _
     }
   else
@@ -524,7 +524,7 @@ nat64_interfaces_walk (nat64_interface_walk_fn_t fn, void *ctx)
 }
 
 int
-nat64_alloc_out_addr_and_port (u32 fib_index, snat_protocol_t proto,
+nat64_alloc_out_addr_and_port (u32 fib_index, nat_protocol_t proto,
 			       ip4_address_t * addr, u16 * port,
 			       u32 thread_index)
 {
@@ -560,7 +560,7 @@ nat64_free_out_addr_and_port (struct nat64_db_s *db, ip4_address_t * addr,
   int i;
   snat_address_t *a;
   u32 thread_index = db - nm->db;
-  snat_protocol_t proto = ip_proto_to_snat_proto (protocol);
+  nat_protocol_t proto = ip_proto_to_nat_proto (protocol);
   u16 port_host_byte_order = clib_net_to_host_u16 (port);
 
   for (i = 0; i < vec_len (nm->addr_pool); i++)
@@ -571,13 +571,13 @@ nat64_free_out_addr_and_port (struct nat64_db_s *db, ip4_address_t * addr,
       switch (proto)
 	{
 #define _(N, j, n, s) \
-        case SNAT_PROTOCOL_##N: \
+        case NAT_PROTOCOL_##N: \
           ASSERT (a->busy_##n##_port_refcounts[port_host_byte_order] >= 1); \
           --a->busy_##n##_port_refcounts[port_host_byte_order]; \
           a->busy_##n##_ports--; \
           a->busy_##n##_ports_per_thread[thread_index]--; \
           break;
-	  foreach_snat_protocol
+	  foreach_nat_protocol
 #undef _
 	default:
 	  nat_elog_notice ("unknown protocol");
@@ -663,7 +663,7 @@ nat64_add_del_static_bib_entry (ip6_address_t * in_addr,
   nat64_db_bib_entry_t *bibe;
   u32 fib_index = fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP6, vrf_id,
 						     nat_fib_src_hi);
-  snat_protocol_t p = ip_proto_to_snat_proto (proto);
+  nat_protocol_t p = ip_proto_to_nat_proto (proto);
   ip46_address_t addr;
   int i;
   snat_address_t *a;
@@ -707,7 +707,7 @@ nat64_add_del_static_bib_entry (ip6_address_t * in_addr,
 	  switch (p)
 	    {
 #define _(N, j, n, s) \
-            case SNAT_PROTOCOL_##N: \
+            case NAT_PROTOCOL_##N: \
               if (a->busy_##n##_port_refcounts[out_port]) \
                 return VNET_API_ERROR_INVALID_VALUE; \
 	      ++a->busy_##n##_port_refcounts[out_port]; \
@@ -717,7 +717,7 @@ nat64_add_del_static_bib_entry (ip6_address_t * in_addr,
                   a->busy_##n##_ports_per_thread[thread_index]++; \
                 } \
               break;
-	      foreach_snat_protocol
+	      foreach_nat_protocol
 #undef _
 	    default:
 	      clib_memset (&addr, 0, sizeof (addr));
@@ -870,12 +870,12 @@ nat64_session_reset_timeout (nat64_db_st_entry_t * ste, vlib_main_t * vm)
   nat64_main_t *nm = &nat64_main;
   u32 now = (u32) vlib_time_now (vm);
 
-  switch (ip_proto_to_snat_proto (ste->proto))
+  switch (ip_proto_to_nat_proto (ste->proto))
     {
-    case SNAT_PROTOCOL_ICMP:
+    case NAT_PROTOCOL_ICMP:
       ste->expire = now + nm->icmp_timeout;
       return;
-    case SNAT_PROTOCOL_TCP:
+    case NAT_PROTOCOL_TCP:
       {
 	switch (ste->tcp_state)
 	  {
@@ -894,7 +894,7 @@ nat64_session_reset_timeout (nat64_db_st_entry_t * ste, vlib_main_t * vm)
 	    return;
 	  }
       }
-    case SNAT_PROTOCOL_UDP:
+    case NAT_PROTOCOL_UDP:
       ste->expire = now + nm->udp_timeout;
       return;
     default:
diff --git a/src/plugins/nat/nat64.h b/src/plugins/nat/nat64.h
index f13334447b0..7121638b570 100644
--- a/src/plugins/nat/nat64.h
+++ b/src/plugins/nat/nat64.h
@@ -226,7 +226,7 @@ int nat64_add_del_static_bib_entry (ip6_address_t * in_addr,
  *
  * @returns 0 on success, non-zero value otherwise.
  */
-int nat64_alloc_out_addr_and_port (u32 fib_index, snat_protocol_t proto,
+int nat64_alloc_out_addr_and_port (u32 fib_index, nat_protocol_t proto,
 				   ip4_address_t * addr, u16 * port,
 				   u32 thread_index);
 
diff --git a/src/plugins/nat/nat64_cli.c b/src/plugins/nat/nat64_cli.c
index be468df1753..6fc047f56c5 100644
--- a/src/plugins/nat/nat64_cli.c
+++ b/src/plugins/nat/nat64_cli.c
@@ -119,7 +119,7 @@ nat64_cli_pool_walk (snat_address_t * ap, void *ctx)
 
 #define _(N, i, n, s) \
   vlib_cli_output (vm, "  %d busy %s ports", ap->busy_##n##_ports, s);
-  foreach_snat_protocol
+  foreach_nat_protocol
 #undef _
     return 0;
 }
@@ -288,7 +288,7 @@ nat64_add_del_static_bib_command_fn (vlib_main_t *
   u32 in_port = 0;
   u32 out_port = 0;
   u32 vrf_id = 0, protocol;
-  snat_protocol_t proto = 0;
+  nat_protocol_t proto = 0;
   u8 p = 0;
   int rv;
 
@@ -305,7 +305,7 @@ nat64_add_del_static_bib_command_fn (vlib_main_t *
 	;
       else if (unformat (line_input, "vrf %u", &vrf_id))
 	;
-      else if (unformat (line_input, "%U", unformat_snat_protocol, &proto))
+      else if (unformat (line_input, "%U", unformat_nat_protocol, &proto))
 	;
       else
 	if (unformat
@@ -338,7 +338,7 @@ nat64_add_del_static_bib_command_fn (vlib_main_t *
 	  goto done;
 	}
 
-      p = snat_proto_to_ip_proto (proto);
+      p = nat_proto_to_ip_proto (proto);
     }
 
   rv =
@@ -394,8 +394,8 @@ nat64_cli_bib_walk (nat64_db_bib_entry_t * bibe, void *ctx)
 		       clib_net_to_host_u16 (bibe->in_port),
 		       format_ip4_address, &bibe->out_addr,
 		       clib_net_to_host_u16 (bibe->out_port),
-		       format_snat_protocol,
-		       ip_proto_to_snat_proto (bibe->proto), fib->ft_table_id,
+		       format_nat_protocol,
+		       ip_proto_to_nat_proto (bibe->proto), fib->ft_table_id,
 		       bibe->is_static ? "static" : "dynamic", bibe->ses_num);
       break;
     default:
@@ -415,15 +415,15 @@ nat64_show_bib_command_fn (vlib_main_t * vm,
   nat64_main_t *nm = &nat64_main;
   unformat_input_t _line_input, *line_input = &_line_input;
   clib_error_t *error = 0;
-  u32 proto = ~0;
+  u32 proto = NAT_PROTOCOL_OTHER;
   u8 p = 255;
   nat64_db_t *db;
 
   if (!unformat_user (input, unformat_line_input, line_input))
     return 0;
 
-  if (unformat (line_input, "%U", unformat_snat_protocol, &proto))
-    p = snat_proto_to_ip_proto (proto);
+  if (unformat (line_input, "%U", unformat_nat_protocol, &proto))
+    p = nat_proto_to_ip_proto (proto);
   else if (unformat (line_input, "unknown"))
     p = 0;
   else if (unformat (line_input, "all"))
@@ -438,8 +438,7 @@ nat64_show_bib_command_fn (vlib_main_t * vm,
   if (p == 255)
     vlib_cli_output (vm, "NAT64 BIB entries:");
   else
-    vlib_cli_output (vm, "NAT64 %U BIB entries:", format_snat_protocol,
-		     proto);
+    vlib_cli_output (vm, "NAT64 %U BIB entries:", format_nat_protocol, proto);
 
   /* *INDENT-OFF* */
   vec_foreach (db, nm->db)
@@ -484,8 +483,8 @@ nat64_cli_st_walk (nat64_db_st_entry_t * ste, void *arg)
 		     format_ip4_address, &bibe->out_addr,
 		     format_ip4_address, &ste->out_r_addr,
 		     clib_net_to_host_u16 (bibe->out_port),
-		     format_snat_protocol,
-		     ip_proto_to_snat_proto (bibe->proto), vrf_id);
+		     format_nat_protocol,
+		     ip_proto_to_nat_proto (bibe->proto), vrf_id);
   else if (ste->proto == IP_PROTOCOL_TCP || ste->proto == IP_PROTOCOL_UDP)
     vlib_cli_output (vm, " %U %u %U %u %U %u %U %u protcol %U vrf %u",
 		     format_ip6_address, &bibe->in_addr,
@@ -496,8 +495,8 @@ nat64_cli_st_walk (nat64_db_st_entry_t * ste, void *arg)
 		     clib_net_to_host_u16 (bibe->out_port),
 		     format_ip4_address, &ste->out_r_addr,
 		     clib_net_to_host_u16 (ste->r_port),
-		     format_snat_protocol,
-		     ip_proto_to_snat_proto (bibe->proto), vrf_id);
+		     format_nat_protocol,
+		     ip_proto_to_nat_proto (bibe->proto), vrf_id);
   else
     vlib_cli_output (vm, " %U %U %U %U protocol %u vrf %u",
 		     format_ip6_address, &bibe->in_addr,
@@ -516,7 +515,7 @@ nat64_show_st_command_fn (vlib_main_t * vm,
   nat64_main_t *nm = &nat64_main;
   unformat_input_t _line_input, *line_input = &_line_input;
   clib_error_t *error = 0;
-  u32 proto = ~0;
+  u32 proto = NAT_PROTOCOL_OTHER;
   u8 p = 255;
   nat64_db_t *db;
   nat64_cli_st_walk_ctx_t ctx = {
@@ -526,8 +525,8 @@ nat64_show_st_command_fn (vlib_main_t * vm,
   if (!unformat_user (input, unformat_line_input, line_input))
     return 0;
 
-  if (unformat (line_input, "%U", unformat_snat_protocol, &proto))
-    p = snat_proto_to_ip_proto (proto);
+  if (unformat (line_input, "%U", unformat_nat_protocol, &proto))
+    p = nat_proto_to_ip_proto (proto);
   else if (unformat (line_input, "unknown"))
     p = 0;
   else if (unformat (line_input, "all"))
@@ -542,7 +541,7 @@ nat64_show_st_command_fn (vlib_main_t * vm,
   if (p == 255)
     vlib_cli_output (vm, "NAT64 sessions:");
   else
-    vlib_cli_output (vm, "NAT64 %U sessions:", format_snat_protocol, proto);
+    vlib_cli_output (vm, "NAT64 %U sessions:", format_nat_protocol, proto);
   /* *INDENT-OFF* */
   vec_foreach (db, nm->db)
     {
diff --git a/src/plugins/nat/nat64_db.c b/src/plugins/nat/nat64_db.c
index 8c004f14686..6e4973b249a 100644
--- a/src/plugins/nat/nat64_db.c
+++ b/src/plugins/nat/nat64_db.c
@@ -69,15 +69,15 @@ nat64_db_bib_entry_create (u32 thread_index, nat64_db_t * db,
     }
 
   /* create pool entry */
-  switch (ip_proto_to_snat_proto (proto))
+  switch (ip_proto_to_nat_proto (proto))
     {
 /* *INDENT-OFF* */
 #define _(N, i, n, s) \
-    case SNAT_PROTOCOL_##N: \
+    case NAT_PROTOCOL_##N: \
       pool_get (db->bib._##n##_bib, bibe); \
       kv.value = bibe - db->bib._##n##_bib; \
       break;
-      foreach_snat_protocol
+      foreach_nat_protocol
 #undef _
 /* *INDENT-ON* */
     default:
@@ -136,15 +136,15 @@ nat64_db_bib_entry_free (u32 thread_index, nat64_db_t * db,
   nat64_db_st_entry_t *st, *ste;
   fib_table_t *fib;
 
-  switch (ip_proto_to_snat_proto (bibe->proto))
+  switch (ip_proto_to_nat_proto (bibe->proto))
     {
 /* *INDENT-OFF* */
 #define _(N, i, n, s) \
-    case SNAT_PROTOCOL_##N: \
+    case NAT_PROTOCOL_##N: \
       bib = db->bib._##n##_bib; \
       st = db->st._##n##_st; \
       break;
-      foreach_snat_protocol
+      foreach_nat_protocol
 #undef _
 /* *INDENT-ON* */
     default:
@@ -214,14 +214,14 @@ nat64_db_bib_entry_find (nat64_db_t * db, ip46_address_t * addr, u16 port,
   clib_bihash_kv_24_8_t kv, value;
   nat64_db_bib_entry_t *bib;
 
-  switch (ip_proto_to_snat_proto (proto))
+  switch (ip_proto_to_nat_proto (proto))
     {
 /* *INDENT-OFF* */
 #define _(N, i, n, s) \
-    case SNAT_PROTOCOL_##N: \
+    case NAT_PROTOCOL_##N: \
       bib = db->bib._##n##_bib; \
       break;
-      foreach_snat_protocol
+      foreach_nat_protocol
 #undef _
 /* *INDENT-ON* */
     default:
@@ -262,7 +262,7 @@ nat64_db_bib_walk (nat64_db_t * db, u8 proto,
         if (fn (bibe, ctx)) \
           return; \
       }));
-      foreach_snat_protocol
+      foreach_nat_protocol
     #undef _
       bib = db->bib._unk_proto_bib;
       pool_foreach (bibe, bib, ({
@@ -273,14 +273,14 @@ nat64_db_bib_walk (nat64_db_t * db, u8 proto,
     }
   else
     {
-      switch (ip_proto_to_snat_proto (proto))
+      switch (ip_proto_to_nat_proto (proto))
 	{
     /* *INDENT-OFF* */
     #define _(N, i, n, s) \
-        case SNAT_PROTOCOL_##N: \
+        case NAT_PROTOCOL_##N: \
           bib = db->bib._##n##_bib; \
           break;
-          foreach_snat_protocol
+          foreach_nat_protocol
     #undef _
     /* *INDENT-ON* */
 	default:
@@ -303,14 +303,14 @@ nat64_db_bib_entry_by_index (nat64_db_t * db, u8 proto, u32 bibe_index)
 {
   nat64_db_bib_entry_t *bib;
 
-  switch (ip_proto_to_snat_proto (proto))
+  switch (ip_proto_to_nat_proto (proto))
     {
 /* *INDENT-OFF* */
 #define _(N, i, n, s) \
-    case SNAT_PROTOCOL_##N: \
+    case NAT_PROTOCOL_##N: \
       bib = db->bib._##n##_bib; \
       break;
-      foreach_snat_protocol
+      foreach_nat_protocol
 #undef _
 /* *INDENT-ON* */
     default:
@@ -336,7 +336,7 @@ nat64_db_st_walk (nat64_db_t * db, u8 proto,
         if (fn (ste, ctx)) \
           return; \
       }));
-      foreach_snat_protocol
+      foreach_nat_protocol
     #undef _
       st = db->st._unk_proto_st;
       pool_foreach (ste, st, ({
@@ -347,14 +347,14 @@ nat64_db_st_walk (nat64_db_t * db, u8 proto,
     }
   else
     {
-      switch (ip_proto_to_snat_proto (proto))
+      switch (ip_proto_to_nat_proto (proto))
 	{
     /* *INDENT-OFF* */
     #define _(N, i, n, s) \
-        case SNAT_PROTOCOL_##N: \
+        case NAT_PROTOCOL_##N: \
           st = db->st._##n##_st; \
           break;
-          foreach_snat_protocol
+          foreach_nat_protocol
     #undef _
     /* *INDENT-ON* */
 	default:
@@ -391,16 +391,16 @@ nat64_db_st_entry_create (u32 thread_index, nat64_db_t * db,
     }
 
   /* create pool entry */
-  switch (ip_proto_to_snat_proto (bibe->proto))
+  switch (ip_proto_to_nat_proto (bibe->proto))
     {
 /* *INDENT-OFF* */
 #define _(N, i, n, s) \
-    case SNAT_PROTOCOL_##N: \
+    case NAT_PROTOCOL_##N: \
       pool_get (db->st._##n##_st, ste); \
       kv.value = ste - db->st._##n##_st; \
       bib = db->bib._##n##_bib; \
       break;
-      foreach_snat_protocol
+      foreach_nat_protocol
 #undef _
 /* *INDENT-ON* */
     default:
@@ -478,15 +478,15 @@ nat64_db_st_entry_free (u32 thread_index,
   clib_bihash_kv_48_8_t kv;
   fib_table_t *fib;
 
-  switch (ip_proto_to_snat_proto (ste->proto))
+  switch (ip_proto_to_nat_proto (ste->proto))
     {
 /* *INDENT-OFF* */
 #define _(N, i, n, s) \
-    case SNAT_PROTOCOL_##N: \
+    case NAT_PROTOCOL_##N: \
       st = db->st._##n##_st; \
       bib = db->bib._##n##_bib; \
       break;
-      foreach_snat_protocol
+      foreach_nat_protocol
 #undef _
 /* *INDENT-ON* */
     default:
@@ -563,14 +563,14 @@ nat64_db_st_entry_find (nat64_db_t * db, ip46_address_t * l_addr,
   nat64_db_st_entry_key_t ste_key;
   clib_bihash_kv_48_8_t kv, value;
 
-  switch (ip_proto_to_snat_proto (proto))
+  switch (ip_proto_to_nat_proto (proto))
     {
 /* *INDENT-OFF* */
 #define _(N, i, n, s) \
-    case SNAT_PROTOCOL_##N: \
+    case NAT_PROTOCOL_##N: \
       st = db->st._##n##_st; \
       break;
-      foreach_snat_protocol
+      foreach_nat_protocol
 #undef _
 /* *INDENT-ON* */
     default:
@@ -606,14 +606,14 @@ nat64_db_st_entry_get_index (nat64_db_t * db, nat64_db_st_entry_t * ste)
 {
   nat64_db_st_entry_t *st;
 
-  switch (ip_proto_to_snat_proto (ste->proto))
+  switch (ip_proto_to_nat_proto (ste->proto))
     {
 /* *INDENT-OFF* */
 #define _(N, i, n, s) \
-    case SNAT_PROTOCOL_##N: \
+    case NAT_PROTOCOL_##N: \
       st = db->st._##n##_st; \
       break;
-      foreach_snat_protocol
+      foreach_nat_protocol
 #undef _
 /* *INDENT-ON* */
     default:
@@ -629,14 +629,14 @@ nat64_db_st_entry_by_index (nat64_db_t * db, u8 proto, u32 ste_index)
 {
   nat64_db_st_entry_t *st;
 
-  switch (ip_proto_to_snat_proto (proto))
+  switch (ip_proto_to_nat_proto (proto))
     {
 /* *INDENT-OFF* */
 #define _(N, i, n, s) \
-    case SNAT_PROTOCOL_##N: \
+    case NAT_PROTOCOL_##N: \
       st = db->st._##n##_st; \
       break;
-      foreach_snat_protocol
+      foreach_nat_protocol
 #undef _
 /* *INDENT-ON* */
     default:
@@ -657,7 +657,7 @@ nad64_db_st_free_expired (u32 thread_index, nat64_db_t * db, u32 now)
 #define _(N, i, n, s) \
   st = db->st._##n##_st; \
   pool_foreach (ste, st, ({\
-    if (i == SNAT_PROTOCOL_TCP && !ste->tcp_state) \
+    if (i == NAT_PROTOCOL_TCP && !ste->tcp_state) \
       continue; \
     if (ste->expire < now) \
       vec_add1 (ste_to_be_free, ste - st); \
@@ -667,7 +667,7 @@ nad64_db_st_free_expired (u32 thread_index, nat64_db_t * db, u32 now)
                             pool_elt_at_index(st, ste_index[0])); \
   vec_free (ste_to_be_free); \
   ste_to_be_free = 0;
-  foreach_snat_protocol
+  foreach_nat_protocol
 #undef _
   st = db->st._unk_proto_st;
   pool_foreach (ste, st, ({
@@ -703,7 +703,7 @@ nat64_db_free_out_addr (u32 thread_index,
                             pool_elt_at_index(st, ste_index[0])); \
   vec_free (ste_to_be_free); \
   ste_to_be_free = 0;
-  foreach_snat_protocol
+  foreach_nat_protocol
 #undef _
   st = db->st._unk_proto_st;
   pool_foreach (ste, st, ({
diff --git a/src/plugins/nat/nat64_db.h b/src/plugins/nat/nat64_db.h
index 68f048ca59e..76e00c9227b 100644
--- a/src/plugins/nat/nat64_db.h
+++ b/src/plugins/nat/nat64_db.h
@@ -60,7 +60,7 @@ typedef struct
 /* *INDENT-OFF* */
 #define _(N, i, n, s) \
   nat64_db_bib_entry_t *_##n##_bib;
-  foreach_snat_protocol
+  foreach_nat_protocol
 #undef _
 /* *INDENT-ON* */
   nat64_db_bib_entry_t *_unk_proto_bib;
@@ -110,7 +110,7 @@ typedef struct
 /* *INDENT-OFF* */
 #define _(N, i, n, s) \
   nat64_db_st_entry_t *_##n##_st;
-  foreach_snat_protocol
+  foreach_nat_protocol
 #undef _
 /* *INDENT-ON* */
   nat64_db_st_entry_t *_unk_proto_st;
diff --git a/src/plugins/nat/nat64_in2out.c b/src/plugins/nat/nat64_in2out.c
index 8d4b1a89cad..38e98340b8c 100644
--- a/src/plugins/nat/nat64_in2out.c
+++ b/src/plugins/nat/nat64_in2out.c
@@ -224,7 +224,7 @@ nat64_in2out_tcp_udp (vlib_main_t * vm, vlib_buffer_t * p, u16 l4_offset,
 	  u16 out_port;
 	  ip4_address_t out_addr;
 	  if (nat64_alloc_out_addr_and_port
-	      (fib_index, ip_proto_to_snat_proto (proto), &out_addr,
+	      (fib_index, ip_proto_to_nat_proto (proto), &out_addr,
 	       &out_port, ctx->thread_index))
 	    return -1;
 
@@ -335,7 +335,7 @@ nat64_in2out_icmp_set_cb (ip6_header_t * ip6, ip4_header_t * ip4, void *arg)
 	      u16 out_id;
 	      ip4_address_t out_addr;
 	      if (nat64_alloc_out_addr_and_port
-		  (fib_index, SNAT_PROTOCOL_ICMP, &out_addr, &out_id,
+		  (fib_index, NAT_PROTOCOL_ICMP, &out_addr, &out_id,
 		   ctx->thread_index))
 		return -1;
 
@@ -715,7 +715,7 @@ nat64_in2out_tcp_udp_hairpinning (vlib_main_t * vm, vlib_buffer_t * b,
 	  u16 out_port;
 	  ip4_address_t out_addr;
 	  if (nat64_alloc_out_addr_and_port
-	      (fib_index, ip_proto_to_snat_proto (proto), &out_addr,
+	      (fib_index, ip_proto_to_nat_proto (proto), &out_addr,
 	       &out_port, thread_index))
 	    return -1;
 
@@ -1112,11 +1112,11 @@ nat64_in2out_node_fn_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
 	      goto trace0;
 	    }
 
-	  proto0 = ip_proto_to_snat_proto (l4_protocol0);
+	  proto0 = ip_proto_to_nat_proto (l4_protocol0);
 
 	  if (is_slow_path)
 	    {
-	      if (PREDICT_TRUE (proto0 == ~0))
+	      if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_OTHER))
 		{
 		  other_packets++;
 		  if (is_hairpinning (&ip60->dst_address))
@@ -1146,14 +1146,14 @@ nat64_in2out_node_fn_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
 	    }
 	  else
 	    {
-	      if (PREDICT_FALSE (proto0 == ~0))
+	      if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 		{
 		  next0 = NAT64_IN2OUT_NEXT_SLOWPATH;
 		  goto trace0;
 		}
 	    }
 
-	  if (proto0 == SNAT_PROTOCOL_ICMP)
+	  if (proto0 == NAT_PROTOCOL_ICMP)
 	    {
 	      icmp_packets++;
 	      if (is_hairpinning (&ip60->dst_address))
@@ -1178,9 +1178,9 @@ nat64_in2out_node_fn_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
 		  goto trace0;
 		}
 	    }
-	  else if (proto0 == SNAT_PROTOCOL_TCP || proto0 == SNAT_PROTOCOL_UDP)
+	  else if (proto0 == NAT_PROTOCOL_TCP || proto0 == NAT_PROTOCOL_UDP)
 	    {
-	      if (proto0 == SNAT_PROTOCOL_TCP)
+	      if (proto0 == NAT_PROTOCOL_TCP)
 		tcp_packets++;
 	      else
 		udp_packets++;
diff --git a/src/plugins/nat/nat64_out2in.c b/src/plugins/nat/nat64_out2in.c
index 6c0075102a1..ef0f8214ddd 100644
--- a/src/plugins/nat/nat64_out2in.c
+++ b/src/plugins/nat/nat64_out2in.c
@@ -575,9 +575,9 @@ VLIB_NODE_FN (nat64_out2in_node) (vlib_main_t * vm,
 
 	  next0 = NAT64_OUT2IN_NEXT_IP6_LOOKUP;
 
-	  proto0 = ip_proto_to_snat_proto (ip40->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip40->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    {
 	      if (nat64_out2in_unk_proto (vm, b0, &ctx0))
 		{
@@ -588,7 +588,7 @@ VLIB_NODE_FN (nat64_out2in_node) (vlib_main_t * vm,
 	      goto trace0;
 	    }
 
-	  if (proto0 == SNAT_PROTOCOL_ICMP)
+	  if (proto0 == NAT_PROTOCOL_ICMP)
 	    {
 	      icmp_packets++;
 	      if (icmp_to_icmp6
@@ -602,7 +602,7 @@ VLIB_NODE_FN (nat64_out2in_node) (vlib_main_t * vm,
 	    }
 	  else
 	    {
-	      if (proto0 == SNAT_PROTOCOL_TCP)
+	      if (proto0 == NAT_PROTOCOL_TCP)
 		tcp_packets++;
 	      else
 		udp_packets++;
@@ -614,7 +614,7 @@ VLIB_NODE_FN (nat64_out2in_node) (vlib_main_t * vm,
 		   * Send DHCP packets to the ipv4 stack, or we won't
 		   * be able to use dhcp client on the outside interface
 		   */
-		  if ((proto0 == SNAT_PROTOCOL_UDP)
+		  if ((proto0 == NAT_PROTOCOL_UDP)
 		      && (udp0->dst_port ==
 			  clib_host_to_net_u16 (UDP_DST_PORT_dhcp_to_client)))
 		    {
diff --git a/src/plugins/nat/nat_affinity.c b/src/plugins/nat/nat_affinity.c
index 5a6927118aa..2c22ae0e097 100644
--- a/src/plugins/nat/nat_affinity.c
+++ b/src/plugins/nat/nat_affinity.c
@@ -38,7 +38,7 @@ format_affinity_kvp (u8 * s, va_list * args)
 	      format_ip4_address, &k.client_addr,
 	      format_ip4_address, &k.service_addr,
 	      clib_net_to_host_u16 (k.service_port),
-	      format_snat_protocol, k.proto);
+	      format_nat_protocol, k.proto);
 
   return s;
 }
diff --git a/src/plugins/nat/nat_api.c b/src/plugins/nat/nat_api.c
index c58e88bd7f0..74f24d85cf8 100644
--- a/src/plugins/nat/nat_api.c
+++ b/src/plugins/nat/nat_api.c
@@ -1098,7 +1098,7 @@ static void
   u32 vrf_id, external_sw_if_index;
   twice_nat_type_t twice_nat = TWICE_NAT_DISABLED;
   int rv = 0;
-  snat_protocol_t proto;
+  nat_protocol_t proto;
   u8 *tag = 0;
 
   if (sm->deterministic)
@@ -1118,7 +1118,7 @@ static void
 
   vrf_id = clib_net_to_host_u32 (mp->vrf_id);
   external_sw_if_index = clib_net_to_host_u32 (mp->external_sw_if_index);
-  proto = ip_proto_to_snat_proto (mp->protocol);
+  proto = ip_proto_to_nat_proto (mp->protocol);
 
   if (mp->flags & NAT_API_IS_TWICE_NAT)
     twice_nat = TWICE_NAT;
@@ -1202,7 +1202,7 @@ send_nat44_static_mapping_details (snat_static_mapping_t * m,
     }
   else
     {
-      rmp->protocol = snat_proto_to_ip_proto (m->proto);
+      rmp->protocol = nat_proto_to_ip_proto (m->proto);
       rmp->external_port = htons (m->external_port);
       rmp->local_port = htons (m->local_port);
     }
@@ -1239,7 +1239,7 @@ send_nat44_static_map_resolve_details (snat_static_map_resolve_t * m,
     }
   else
     {
-      rmp->protocol = snat_proto_to_ip_proto (m->proto);
+      rmp->protocol = nat_proto_to_ip_proto (m->proto);
       rmp->external_port = htons (m->e_port);
       rmp->local_port = htons (m->l_port);
     }
@@ -1303,7 +1303,7 @@ static void
   u16 port = 0;
   u32 vrf_id, sw_if_index;
   int rv = 0;
-  snat_protocol_t proto = ~0;
+  nat_protocol_t proto = NAT_PROTOCOL_OTHER;
   u8 *tag = 0;
 
   if (sm->deterministic)
@@ -1315,7 +1315,7 @@ static void
   if (!(mp->flags & NAT_API_IS_ADDR_ONLY))
     {
       port = clib_net_to_host_u16 (mp->port);
-      proto = ip_proto_to_snat_proto (mp->protocol);
+      proto = ip_proto_to_nat_proto (mp->protocol);
     }
   vrf_id = clib_net_to_host_u32 (mp->vrf_id);
   sw_if_index = clib_net_to_host_u32 (mp->sw_if_index);
@@ -1379,7 +1379,7 @@ send_nat44_identity_mapping_details (snat_static_mapping_t * m, int index,
   rmp->port = htons (m->local_port);
   rmp->sw_if_index = ~0;
   rmp->vrf_id = htonl (local->vrf_id);
-  rmp->protocol = snat_proto_to_ip_proto (m->proto);
+  rmp->protocol = nat_proto_to_ip_proto (m->proto);
   rmp->context = context;
   if (m->tag)
     strncpy ((char *) rmp->tag, (char *) m->tag, vec_len (m->tag));
@@ -1406,7 +1406,7 @@ send_nat44_identity_map_resolve_details (snat_static_map_resolve_t * m,
   rmp->port = htons (m->l_port);
   rmp->sw_if_index = htonl (m->sw_if_index);
   rmp->vrf_id = htonl (m->vrf_id);
-  rmp->protocol = snat_proto_to_ip_proto (m->proto);
+  rmp->protocol = nat_proto_to_ip_proto (m->proto);
   rmp->context = context;
   if (m->tag)
     strncpy ((char *) rmp->tag, (char *) m->tag, vec_len (m->tag));
@@ -1657,7 +1657,7 @@ send_nat44_user_session_details (snat_session_t * s,
     {
       rmp->outside_port = s->out2in.port;
       rmp->inside_port = s->in2out.port;
-      rmp->protocol = ntohs (snat_proto_to_ip_proto (s->in2out.protocol));
+      rmp->protocol = ntohs (nat_proto_to_ip_proto (s->in2out.protocol));
     }
   if (is_ed_session (s) || is_fwd_bypass_session (s))
     {
@@ -1788,7 +1788,7 @@ static void
   int rv = 0;
   nat44_lb_addr_port_t *locals = 0;
   ip4_address_t e_addr;
-  snat_protocol_t proto;
+  nat_protocol_t proto;
   u8 *tag = 0;
 
   if (!sm->endpoint_dependent)
@@ -1801,7 +1801,7 @@ static void
     unformat_nat44_lb_addr_port (mp->locals,
 				 clib_net_to_host_u32 (mp->local_num));
   clib_memcpy (&e_addr, mp->external_addr, 4);
-  proto = ip_proto_to_snat_proto (mp->protocol);
+  proto = ip_proto_to_nat_proto (mp->protocol);
 
   if (mp->flags & NAT_API_IS_TWICE_NAT)
     twice_nat = TWICE_NAT;
@@ -1848,7 +1848,7 @@ static void
   vl_api_nat44_lb_static_mapping_add_del_local_reply_t *rmp;
   int rv = 0;
   ip4_address_t e_addr, l_addr;
-  snat_protocol_t proto;
+  nat_protocol_t proto;
 
   if (!sm->endpoint_dependent)
     {
@@ -1858,7 +1858,7 @@ static void
 
   clib_memcpy (&e_addr, mp->external_addr, 4);
   clib_memcpy (&l_addr, mp->local.addr, 4);
-  proto = ip_proto_to_snat_proto (mp->protocol);
+  proto = ip_proto_to_nat_proto (mp->protocol);
 
   rv =
     nat44_lb_static_mapping_add_del_local (e_addr,
@@ -1907,7 +1907,7 @@ send_nat44_lb_static_mapping_details (snat_static_mapping_t * m,
 
   clib_memcpy (rmp->external_addr, &(m->external_addr), 4);
   rmp->external_port = ntohs (m->external_port);
-  rmp->protocol = snat_proto_to_ip_proto (m->proto);
+  rmp->protocol = nat_proto_to_ip_proto (m->proto);
   rmp->context = context;
 
   if (m->twice_nat == TWICE_NAT)
@@ -1980,7 +1980,7 @@ vl_api_nat44_del_session_t_handler (vl_api_nat44_del_session_t * mp)
   u32 vrf_id;
   int rv = 0;
   u8 is_in;
-  snat_protocol_t proto;
+  nat_protocol_t proto;
 
   if (sm->deterministic)
     {
@@ -1991,7 +1991,7 @@ vl_api_nat44_del_session_t_handler (vl_api_nat44_del_session_t * mp)
   memcpy (&addr.as_u8, mp->address, 4);
   port = clib_net_to_host_u16 (mp->port);
   vrf_id = clib_net_to_host_u32 (mp->vrf_id);
-  proto = ip_proto_to_snat_proto (mp->protocol);
+  proto = ip_proto_to_nat_proto (mp->protocol);
   memcpy (&eh_addr.as_u8, mp->ext_host_address, 4);
   eh_port = clib_net_to_host_u16 (mp->ext_host_port);
 
diff --git a/src/plugins/nat/nat_det_in2out.c b/src/plugins/nat/nat_det_in2out.c
index dc2873ee110..cf50805c1a3 100644
--- a/src/plugins/nat/nat_det_in2out.c
+++ b/src/plugins/nat/nat_det_in2out.c
@@ -126,7 +126,7 @@ icmp_match_in2out_det (snat_main_t * sm, vlib_node_runtime_t * node,
   if (!icmp_type_is_error_message
       (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags))
     {
-      protocol = SNAT_PROTOCOL_ICMP;
+      protocol = NAT_PROTOCOL_ICMP;
       in_addr = ip0->src_address;
       in_port = vnet_buffer (b0)->ip.reass.l4_src_port;
     }
@@ -135,17 +135,17 @@ icmp_match_in2out_det (snat_main_t * sm, vlib_node_runtime_t * node,
       /* if error message, then it's not fragmented and we can access it */
       inner_ip0 = (ip4_header_t *) (echo0 + 1);
       l4_header = ip4_next_header (inner_ip0);
-      protocol = ip_proto_to_snat_proto (inner_ip0->protocol);
+      protocol = ip_proto_to_nat_proto (inner_ip0->protocol);
       in_addr = inner_ip0->dst_address;
       switch (protocol)
 	{
-	case SNAT_PROTOCOL_ICMP:
+	case NAT_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:
+	case NAT_PROTOCOL_UDP:
+	case NAT_PROTOCOL_TCP:
 	  in_port = ((tcp_udp_header_t *) l4_header)->dst_port;
 	  break;
 	default:
@@ -334,9 +334,9 @@ VLIB_NODE_FN (snat_det_in2out_node) (vlib_main_t * vm,
 	      goto trace0;
 	    }
 
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 	    {
 	      rx_fib_index0 =
 		ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
@@ -411,7 +411,7 @@ VLIB_NODE_FN (snat_det_in2out_node) (vlib_main_t * vm,
 				 src_address /* changed member */ );
 	  ip0->checksum = ip_csum_fold (sum0);
 
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      if (tcp0->flags & TCP_FLAG_SYN)
 		ses0->state = SNAT_SESSION_TCP_SYN_SENT;
@@ -507,9 +507,9 @@ VLIB_NODE_FN (snat_det_in2out_node) (vlib_main_t * vm,
 	      goto trace1;
 	    }
 
-	  proto1 = ip_proto_to_snat_proto (ip1->protocol);
+	  proto1 = ip_proto_to_nat_proto (ip1->protocol);
 
-	  if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_ICMP))
 	    {
 	      rx_fib_index1 =
 		ip4_fib_table_get_index_for_sw_if_index (sw_if_index1);
@@ -584,7 +584,7 @@ VLIB_NODE_FN (snat_det_in2out_node) (vlib_main_t * vm,
 				 src_address /* changed member */ );
 	  ip1->checksum = ip_csum_fold (sum1);
 
-	  if (PREDICT_TRUE (proto1 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto1 == NAT_PROTOCOL_TCP))
 	    {
 	      if (tcp1->flags & TCP_FLAG_SYN)
 		ses1->state = SNAT_SESSION_TCP_SYN_SENT;
@@ -716,9 +716,9 @@ VLIB_NODE_FN (snat_det_in2out_node) (vlib_main_t * vm,
 	      goto trace00;
 	    }
 
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 	    {
 	      rx_fib_index0 =
 		ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
@@ -793,7 +793,7 @@ VLIB_NODE_FN (snat_det_in2out_node) (vlib_main_t * vm,
 				 src_address /* changed member */ );
 	  ip0->checksum = ip_csum_fold (sum0);
 
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      if (tcp0->flags & TCP_FLAG_SYN)
 		ses0->state = SNAT_SESSION_TCP_SYN_SENT;
diff --git a/src/plugins/nat/nat_det_out2in.c b/src/plugins/nat/nat_det_out2in.c
index d45df4d2e87..80d9b39b2bb 100644
--- a/src/plugins/nat/nat_det_out2in.c
+++ b/src/plugins/nat/nat_det_out2in.c
@@ -121,7 +121,7 @@ icmp_match_out2in_det (snat_main_t * sm, vlib_node_runtime_t * node,
   if (!icmp_type_is_error_message
       (vnet_buffer (b0)->ip.reass.icmp_type_or_tcp_flags))
     {
-      protocol = SNAT_PROTOCOL_ICMP;
+      protocol = NAT_PROTOCOL_ICMP;
       key0.ext_host_addr = ip0->src_address;
       key0.ext_host_port = 0;
       key0.out_port = vnet_buffer (b0)->ip.reass.l4_src_port;
@@ -132,19 +132,19 @@ icmp_match_out2in_det (snat_main_t * sm, vlib_node_runtime_t * node,
       /* if error message, then it's not fragmented and we can access it */
       inner_ip0 = (ip4_header_t *) (echo0 + 1);
       l4_header = ip4_next_header (inner_ip0);
-      protocol = ip_proto_to_snat_proto (inner_ip0->protocol);
+      protocol = ip_proto_to_nat_proto (inner_ip0->protocol);
       key0.ext_host_addr = inner_ip0->dst_address;
       out_addr = inner_ip0->src_address;
       switch (protocol)
 	{
-	case SNAT_PROTOCOL_ICMP:
+	case NAT_PROTOCOL_ICMP:
 	  inner_icmp0 = (icmp46_header_t *) l4_header;
 	  inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 	  key0.ext_host_port = 0;
 	  key0.out_port = inner_echo0->identifier;
 	  break;
-	case SNAT_PROTOCOL_UDP:
-	case SNAT_PROTOCOL_TCP:
+	case NAT_PROTOCOL_UDP:
+	case NAT_PROTOCOL_TCP:
 	  key0.ext_host_port = ((tcp_udp_header_t *) l4_header)->dst_port;
 	  key0.out_port = ((tcp_udp_header_t *) l4_header)->src_port;
 	  break;
@@ -304,9 +304,9 @@ VLIB_NODE_FN (snat_det_out2in_node) (vlib_main_t * vm,
 	      goto trace0;
 	    }
 
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 	    {
 	      rx_fib_index0 =
 		ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
@@ -361,7 +361,7 @@ VLIB_NODE_FN (snat_det_out2in_node) (vlib_main_t * vm,
 				 dst_address /* changed member */ );
 	  ip0->checksum = ip_csum_fold (sum0);
 
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      if (tcp0->flags & TCP_FLAG_FIN
 		  && ses0->state == SNAT_SESSION_TCP_ESTABLISHED)
@@ -425,9 +425,9 @@ VLIB_NODE_FN (snat_det_out2in_node) (vlib_main_t * vm,
 	      goto trace1;
 	    }
 
-	  proto1 = ip_proto_to_snat_proto (ip1->protocol);
+	  proto1 = ip_proto_to_nat_proto (ip1->protocol);
 
-	  if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_ICMP))
 	    {
 	      rx_fib_index1 =
 		ip4_fib_table_get_index_for_sw_if_index (sw_if_index1);
@@ -482,7 +482,7 @@ VLIB_NODE_FN (snat_det_out2in_node) (vlib_main_t * vm,
 				 dst_address /* changed member */ );
 	  ip1->checksum = ip_csum_fold (sum1);
 
-	  if (PREDICT_TRUE (proto1 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto1 == NAT_PROTOCOL_TCP))
 	    {
 	      if (tcp1->flags & TCP_FLAG_FIN
 		  && ses1->state == SNAT_SESSION_TCP_ESTABLISHED)
@@ -579,9 +579,9 @@ VLIB_NODE_FN (snat_det_out2in_node) (vlib_main_t * vm,
 	      goto trace00;
 	    }
 
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 	    {
 	      rx_fib_index0 =
 		ip4_fib_table_get_index_for_sw_if_index (sw_if_index0);
@@ -636,7 +636,7 @@ VLIB_NODE_FN (snat_det_out2in_node) (vlib_main_t * vm,
 				 dst_address /* changed member */ );
 	  ip0->checksum = ip_csum_fold (sum0);
 
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      if (tcp0->flags & TCP_FLAG_FIN
 		  && ses0->state == SNAT_SESSION_TCP_ESTABLISHED)
diff --git a/src/plugins/nat/nat_format.c b/src/plugins/nat/nat_format.c
index b9241545096..33e9655dc4e 100644
--- a/src/plugins/nat/nat_format.c
+++ b/src/plugins/nat/nat_format.c
@@ -22,13 +22,13 @@
 #include <nat/nat_det.h>
 
 uword
-unformat_snat_protocol (unformat_input_t * input, va_list * args)
+unformat_nat_protocol (unformat_input_t * input, va_list * args)
 {
   u32 *r = va_arg (*args, u32 *);
 
   if (0);
-#define _(N, i, n, s) else if (unformat (input, s)) *r = SNAT_PROTOCOL_##N;
-  foreach_snat_protocol
+#define _(N, i, n, s) else if (unformat (input, s)) *r = NAT_PROTOCOL_##N;
+  foreach_nat_protocol
 #undef _
     else
     return 0;
@@ -36,15 +36,15 @@ unformat_snat_protocol (unformat_input_t * input, va_list * args)
 }
 
 u8 *
-format_snat_protocol (u8 * s, va_list * args)
+format_nat_protocol (u8 * s, va_list * args)
 {
   u32 i = va_arg (*args, u32);
   u8 *t = 0;
 
   switch (i)
     {
-#define _(N, j, n, str) case SNAT_PROTOCOL_##N: t = (u8 *) str; break;
-      foreach_snat_protocol
+#define _(N, j, n, str) case NAT_PROTOCOL_##N: t = (u8 *) str; break;
+      foreach_nat_protocol
 #undef _
     default:
       s = format (s, "unknown");
@@ -80,7 +80,7 @@ format_snat_key (u8 * s, va_list * args)
 
   s = format (s, "%U proto %U port %d fib %d",
 	      format_ip4_address, &key->addr,
-	      format_snat_protocol, key->protocol,
+	      format_nat_protocol, key->protocol,
 	      clib_net_to_host_u16 (key->port), key->fib_index);
   return s;
 }
@@ -92,7 +92,7 @@ format_static_mapping_key (u8 * s, va_list * args)
 
   s = format (s, "%U proto %U port %d fib %d",
 	      format_ip4_address, &key->addr,
-	      format_snat_protocol, key->protocol, key->port, key->fib_index);
+	      format_nat_protocol, key->protocol, key->port, key->fib_index);
   return s;
 }
 
@@ -226,7 +226,7 @@ format_snat_static_mapping (u8 * s, va_list * args)
 		    format_ip4_address, &m->local_addr);
       else
 	s = format (s, "identity mapping %U %U:%d",
-		    format_snat_protocol, m->proto,
+		    format_nat_protocol, m->proto,
 		    format_ip4_address, &m->local_addr, m->local_port);
 
       /* *INDENT-OFF* */
@@ -252,7 +252,7 @@ format_snat_static_mapping (u8 * s, va_list * args)
       if (is_lb_static_mapping (m))
 	{
 	  s = format (s, "%U external %U:%d %s %s",
-		      format_snat_protocol, m->proto,
+		      format_nat_protocol, m->proto,
 		      format_ip4_address, &m->external_addr, m->external_port,
 		      m->twice_nat == TWICE_NAT ? "twice-nat" :
 		      m->twice_nat == TWICE_NAT_SELF ? "self-twice-nat" : "",
@@ -270,7 +270,7 @@ format_snat_static_mapping (u8 * s, va_list * args)
 	}
       else
 	s = format (s, "%U local %U:%d external %U:%d vrf %d %s %s",
-		    format_snat_protocol, m->proto,
+		    format_nat_protocol, m->proto,
 		    format_ip4_address, &m->local_addr, m->local_port,
 		    format_ip4_address, &m->external_addr, m->external_port,
 		    m->vrf_id,
@@ -293,7 +293,7 @@ format_snat_static_map_to_resolve (u8 * s, va_list * args)
 		format_vnet_sw_if_index_name, vnm, m->sw_if_index, m->vrf_id);
   else
     s = format (s, "%U local %U:%d external %U:%d vrf %d",
-		format_snat_protocol, m->proto,
+		format_nat_protocol, m->proto,
 		format_ip4_address, &m->l_addr, m->l_port,
 		format_vnet_sw_if_index_name, vnm, m->sw_if_index,
 		m->e_port, m->vrf_id);
diff --git a/src/plugins/nat/nat_inlines.h b/src/plugins/nat/nat_inlines.h
index a5fa84dcfa9..e5ac421a6f9 100644
--- a/src/plugins/nat/nat_inlines.h
+++ b/src/plugins/nat/nat_inlines.h
@@ -146,49 +146,6 @@ nat_pre_node_fn_inline (vlib_main_t * vm,
   return frame->n_vectors;
 }
 
-always_inline u32
-ip_proto_to_snat_proto (u8 ip_proto)
-{
-  u32 snat_proto = ~0;
-
-  snat_proto = (ip_proto == IP_PROTOCOL_UDP) ? SNAT_PROTOCOL_UDP : snat_proto;
-  snat_proto = (ip_proto == IP_PROTOCOL_TCP) ? SNAT_PROTOCOL_TCP : snat_proto;
-  snat_proto =
-    (ip_proto == IP_PROTOCOL_ICMP) ? SNAT_PROTOCOL_ICMP : snat_proto;
-  snat_proto =
-    (ip_proto == IP_PROTOCOL_ICMP6) ? SNAT_PROTOCOL_ICMP : snat_proto;
-
-  return snat_proto;
-}
-
-always_inline u8
-snat_proto_to_ip_proto (snat_protocol_t snat_proto)
-{
-  u8 ip_proto = ~0;
-
-  ip_proto = (snat_proto == SNAT_PROTOCOL_UDP) ? IP_PROTOCOL_UDP : ip_proto;
-  ip_proto = (snat_proto == SNAT_PROTOCOL_TCP) ? IP_PROTOCOL_TCP : ip_proto;
-  ip_proto = (snat_proto == SNAT_PROTOCOL_ICMP) ? IP_PROTOCOL_ICMP : ip_proto;
-
-  return ip_proto;
-}
-
-static_always_inline u8
-icmp_type_is_error_message (u8 icmp_type)
-{
-  switch (icmp_type)
-    {
-    case ICMP4_destination_unreachable:
-    case ICMP4_time_exceeded:
-    case ICMP4_parameter_problem:
-    case ICMP4_source_quench:
-    case ICMP4_redirect:
-    case ICMP4_alternate_host_address:
-      return 1;
-    }
-  return 0;
-}
-
 always_inline u8
 is_interface_addr (snat_main_t * sm, vlib_node_runtime_t * node,
 		   u32 sw_if_index0, u32 ip4_addr)
@@ -418,11 +375,11 @@ nat44_session_get_timeout (snat_main_t * sm, snat_session_t * s)
 {
   switch (s->in2out.protocol)
     {
-    case SNAT_PROTOCOL_ICMP:
+    case NAT_PROTOCOL_ICMP:
       return sm->icmp_timeout;
-    case SNAT_PROTOCOL_UDP:
+    case NAT_PROTOCOL_UDP:
       return sm->udp_timeout;
-    case SNAT_PROTOCOL_TCP:
+    case NAT_PROTOCOL_TCP:
       {
 	if (s->state)
 	  return sm->tcp_transitory_timeout;
@@ -529,7 +486,7 @@ make_sm_kv (clib_bihash_kv_8_8_t * kv, ip4_address_t * addr, u8 proto,
 
 static_always_inline int
 get_icmp_i2o_ed_key (vlib_buffer_t * b, ip4_header_t * ip0, u32 rx_fib_index,
-		     u64 value, u8 * snat_proto, u16 * l_port, u16 * r_port,
+		     u64 value, u8 * nat_proto, u16 * l_port, u16 * r_port,
 		     clib_bihash_kv_16_8_t * kv)
 {
   u8 proto;
@@ -561,16 +518,16 @@ get_icmp_i2o_ed_key (vlib_buffer_t * b, ip4_header_t * ip0, u32 rx_fib_index,
       proto = inner_ip0->protocol;
       r_addr = &inner_ip0->src_address;
       l_addr = &inner_ip0->dst_address;
-      switch (ip_proto_to_snat_proto (inner_ip0->protocol))
+      switch (ip_proto_to_nat_proto (inner_ip0->protocol))
 	{
-	case SNAT_PROTOCOL_ICMP:
+	case NAT_PROTOCOL_ICMP:
 	  inner_icmp0 = (icmp46_header_t *) l4_header;
 	  inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 	  _r_port = 0;
 	  _l_port = inner_echo0->identifier;
 	  break;
-	case SNAT_PROTOCOL_UDP:
-	case SNAT_PROTOCOL_TCP:
+	case NAT_PROTOCOL_UDP:
+	case NAT_PROTOCOL_TCP:
 	  _l_port = ((tcp_udp_header_t *) l4_header)->dst_port;
 	  _r_port = ((tcp_udp_header_t *) l4_header)->src_port;
 	  break;
@@ -580,9 +537,9 @@ get_icmp_i2o_ed_key (vlib_buffer_t * b, ip4_header_t * ip0, u32 rx_fib_index,
     }
   make_ed_kv (l_addr, r_addr, proto, rx_fib_index, _l_port, _r_port, value,
 	      kv);
-  if (snat_proto)
+  if (nat_proto)
     {
-      *snat_proto = ip_proto_to_snat_proto (proto);
+      *nat_proto = ip_proto_to_nat_proto (proto);
     }
   if (l_port)
     {
@@ -598,7 +555,7 @@ get_icmp_i2o_ed_key (vlib_buffer_t * b, ip4_header_t * ip0, u32 rx_fib_index,
 
 static_always_inline int
 get_icmp_o2i_ed_key (vlib_buffer_t * b, ip4_header_t * ip0, u32 rx_fib_index,
-		     u64 value, u8 * snat_proto, u16 * l_port, u16 * r_port,
+		     u64 value, u8 * nat_proto, u16 * l_port, u16 * r_port,
 		     clib_bihash_kv_16_8_t * kv)
 {
   icmp46_header_t *icmp0;
@@ -629,16 +586,16 @@ get_icmp_o2i_ed_key (vlib_buffer_t * b, ip4_header_t * ip0, u32 rx_fib_index,
       proto = inner_ip0->protocol;
       l_addr = &inner_ip0->src_address;
       r_addr = &inner_ip0->dst_address;
-      switch (ip_proto_to_snat_proto (inner_ip0->protocol))
+      switch (ip_proto_to_nat_proto (inner_ip0->protocol))
 	{
-	case SNAT_PROTOCOL_ICMP:
+	case NAT_PROTOCOL_ICMP:
 	  inner_icmp0 = (icmp46_header_t *) l4_header;
 	  inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 	  _l_port = inner_echo0->identifier;
 	  _r_port = 0;
 	  break;
-	case SNAT_PROTOCOL_UDP:
-	case SNAT_PROTOCOL_TCP:
+	case NAT_PROTOCOL_UDP:
+	case NAT_PROTOCOL_TCP:
 	  _l_port = ((tcp_udp_header_t *) l4_header)->src_port;
 	  _r_port = ((tcp_udp_header_t *) l4_header)->dst_port;
 	  break;
@@ -648,9 +605,9 @@ get_icmp_o2i_ed_key (vlib_buffer_t * b, ip4_header_t * ip0, u32 rx_fib_index,
     }
   make_ed_kv (l_addr, r_addr, proto, rx_fib_index, _l_port, _r_port, value,
 	      kv);
-  if (snat_proto)
+  if (nat_proto)
     {
-      *snat_proto = ip_proto_to_snat_proto (proto);
+      *nat_proto = ip_proto_to_nat_proto (proto);
     }
   if (l_port)
     {
diff --git a/src/plugins/nat/nat_ipfix_logging.c b/src/plugins/nat/nat_ipfix_logging.c
index da8e1f28991..764774224a1 100755
--- a/src/plugins/nat/nat_ipfix_logging.c
+++ b/src/plugins/nat/nat_ipfix_logging.c
@@ -48,7 +48,7 @@ typedef struct
   u8 nat_event;
   u32 src_ip;
   u32 nat_src_ip;
-  snat_protocol_t snat_proto;
+  nat_protocol_t nat_proto;
   u16 src_port;
   u16 nat_src_port;
   u32 vrf_id;
@@ -573,7 +573,7 @@ snat_ipfix_send (u32 thread_index, flow_report_main_t * frm,
 
 static void
 snat_ipfix_logging_nat44_ses (u32 thread_index, u8 nat_event, u32 src_ip,
-                              u32 nat_src_ip, snat_protocol_t snat_proto,
+                              u32 nat_src_ip, nat_protocol_t nat_proto,
                               u16 src_port, u16 nat_src_port, u32 vrf_id,
                               int do_flush)
 {
@@ -586,10 +586,10 @@ snat_ipfix_logging_nat44_ses (u32 thread_index, u8 nat_event, u32 src_ip,
   u32 offset;
   vlib_main_t *vm = vlib_mains[thread_index];
   u64 now;
-  u8 proto = ~0;
+  u8 proto;
   u16 template_id;
 
-  proto = snat_proto_to_ip_proto (snat_proto);
+  proto = nat_proto_to_ip_proto (nat_proto);
 
   now = (u64) ((vlib_time_now (vm) - silm->vlib_time_0) * 1e3);
   now += silm->milisecond_time_0;
@@ -1299,7 +1299,7 @@ snat_ipfix_flush_from_main (void)
  * @param thread_index thread index
  * @param src_ip       source IPv4 address
  * @param nat_src_ip   transaltes source IPv4 address
- * @param snat_proto   NAT transport protocol
+ * @param nat_proto   NAT transport protocol
  * @param src_port     source port
  * @param nat_src_port translated source port
  * @param vrf_id       VRF ID
@@ -1308,14 +1308,14 @@ void
 snat_ipfix_logging_nat44_ses_create (u32 thread_index,
                                      u32 src_ip,
 				     u32 nat_src_ip,
-				     snat_protocol_t snat_proto,
+				     nat_protocol_t nat_proto,
 				     u16 src_port,
 				     u16 nat_src_port, u32 vrf_id)
 {
   skip_if_disabled ();
 
   snat_ipfix_logging_nat44_ses (thread_index, NAT44_SESSION_CREATE, src_ip,
-                                nat_src_ip, snat_proto, src_port, nat_src_port,
+                                nat_src_ip, nat_proto, src_port, nat_src_port,
 				vrf_id, 0);
 }
 
@@ -1325,7 +1325,7 @@ snat_ipfix_logging_nat44_ses_create (u32 thread_index,
  * @param thread_index thread index
  * @param src_ip       source IPv4 address
  * @param nat_src_ip   transaltes source IPv4 address
- * @param snat_proto   NAT transport protocol
+ * @param nat_proto   NAT transport protocol
  * @param src_port     source port
  * @param nat_src_port translated source port
  * @param vrf_id       VRF ID
@@ -1334,14 +1334,14 @@ void
 snat_ipfix_logging_nat44_ses_delete (u32 thread_index,
                                      u32 src_ip,
 				     u32 nat_src_ip,
-				     snat_protocol_t snat_proto,
+				     nat_protocol_t nat_proto,
 				     u16 src_port,
 				     u16 nat_src_port, u32 vrf_id)
 {
   skip_if_disabled ();
 
   snat_ipfix_logging_nat44_ses (thread_index, NAT44_SESSION_DELETE, src_ip,
-                                nat_src_ip, snat_proto, src_port, nat_src_port,
+                                nat_src_ip, nat_proto, src_port, nat_src_port,
 				vrf_id, 0);
 }
 
diff --git a/src/plugins/nat/nat_ipfix_logging.h b/src/plugins/nat/nat_ipfix_logging.h
index 7b5049e0545..f8a9b6b5f5b 100644
--- a/src/plugins/nat/nat_ipfix_logging.h
+++ b/src/plugins/nat/nat_ipfix_logging.h
@@ -113,12 +113,12 @@ void snat_ipfix_logging_init (vlib_main_t * vm);
 int snat_ipfix_logging_enable_disable (int enable, u32 domain_id, u16 src_port);
 void snat_ipfix_logging_nat44_ses_create (u32 thread_index, u32 src_ip,
                                           u32 nat_src_ip,
-                                          snat_protocol_t snat_proto,
+                                          nat_protocol_t nat_proto,
                                           u16 src_port, u16 nat_src_port,
                                           u32 vrf_id);
 void snat_ipfix_logging_nat44_ses_delete (u32 thread_index, u32 src_ip,
                                           u32 nat_src_ip,
-                                          snat_protocol_t snat_proto,
+                                          nat_protocol_t nat_proto,
                                           u16 src_port, u16 nat_src_port,
                                           u32 vrf_id);
 void snat_ipfix_logging_addresses_exhausted(u32 thread_index, u32 pool_id);
diff --git a/src/plugins/nat/nat_test.c b/src/plugins/nat/nat_test.c
index 685f85b92e7..46fbfc7c0cd 100644
--- a/src/plugins/nat/nat_test.c
+++ b/src/plugins/nat/nat_test.c
@@ -299,7 +299,7 @@ static int api_nat44_add_del_static_mapping(vat_main_t * vam)
   u32 local_port = 0, external_port = 0, vrf_id = ~0;
   u32 sw_if_index = ~0;
   u8 sw_if_index_set = 0;
-  u32 proto = ~0;
+  u32 proto = NAT_PROTOCOL_OTHER;
   u8 proto_set = 0;
   int ret;
 
diff --git a/src/plugins/nat/out2in.c b/src/plugins/nat/out2in.c
index 61719c73081..94679fb402c 100755
--- a/src/plugins/nat/out2in.c
+++ b/src/plugins/nat/out2in.c
@@ -278,7 +278,7 @@ static_always_inline
   if (!icmp_type_is_error_message
       (vnet_buffer (b)->ip.reass.icmp_type_or_tcp_flags))
     {
-      key0.protocol = SNAT_PROTOCOL_ICMP;
+      key0.protocol = NAT_PROTOCOL_ICMP;
       key0.addr = ip0->dst_address;
       key0.port = vnet_buffer (b)->ip.reass.l4_src_port;	// TODO should this be dst port?
     }
@@ -286,17 +286,17 @@ static_always_inline
     {
       inner_ip0 = (ip4_header_t *) (echo0 + 1);
       l4_header = ip4_next_header (inner_ip0);
-      key0.protocol = ip_proto_to_snat_proto (inner_ip0->protocol);
+      key0.protocol = ip_proto_to_nat_proto (inner_ip0->protocol);
       key0.addr = inner_ip0->src_address;
       switch (key0.protocol)
 	{
-	case SNAT_PROTOCOL_ICMP:
+	case NAT_PROTOCOL_ICMP:
 	  inner_icmp0 = (icmp46_header_t *) l4_header;
 	  inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 	  key0.port = inner_echo0->identifier;
 	  break;
-	case SNAT_PROTOCOL_UDP:
-	case SNAT_PROTOCOL_TCP:
+	case NAT_PROTOCOL_UDP:
+	case NAT_PROTOCOL_TCP:
 	  key0.port = ((tcp_udp_header_t *) l4_header)->src_port;
 	  break;
 	default:
@@ -624,7 +624,7 @@ icmp_out2in (snat_main_t * sm,
 
 	  switch (protocol)
 	    {
-	    case SNAT_PROTOCOL_ICMP:
+	    case NAT_PROTOCOL_ICMP:
 	      inner_icmp0 = (icmp46_header_t *) l4_header;
 	      inner_echo0 = (icmp_echo_header_t *) (inner_icmp0 + 1);
 
@@ -638,8 +638,8 @@ icmp_out2in (snat_main_t * sm,
 				identifier);
 	      icmp0->checksum = ip_csum_fold (sum0);
 	      break;
-	    case SNAT_PROTOCOL_UDP:
-	    case SNAT_PROTOCOL_TCP:
+	    case NAT_PROTOCOL_UDP:
+	    case NAT_PROTOCOL_TCP:
 	      old_id0 = ((tcp_udp_header_t *) l4_header)->src_port;
 	      new_id0 = sm0.port;
 	      ((tcp_udp_header_t *) l4_header)->src_port = new_id0;
@@ -813,9 +813,9 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 	      goto trace0;
 	    }
 
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    {
 	      if (nat_out2in_sm_unknown_proto (sm, b0, ip0, rx_fib_index0))
 		{
@@ -830,7 +830,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 	      goto trace0;
 	    }
 
-	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 	    {
 	      next0 = icmp_out2in_slow_path
 		(sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
@@ -859,7 +859,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 		   * be able to use dhcp client on the outside interface
 		   */
 		  if (PREDICT_FALSE
-		      (proto0 == SNAT_PROTOCOL_UDP
+		      (proto0 == NAT_PROTOCOL_UDP
 		       && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
 			   clib_host_to_net_u16
 			   (UDP_DST_PORT_dhcp_to_client))))
@@ -903,7 +903,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 				 dst_address /* changed member */ );
 	  ip0->checksum = ip_csum_fold (sum0);
 
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 		{
@@ -985,9 +985,9 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 	      goto trace1;
 	    }
 
-	  proto1 = ip_proto_to_snat_proto (ip1->protocol);
+	  proto1 = ip_proto_to_nat_proto (ip1->protocol);
 
-	  if (PREDICT_FALSE (proto1 == ~0))
+	  if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_OTHER))
 	    {
 	      if (nat_out2in_sm_unknown_proto (sm, b1, ip1, rx_fib_index1))
 		{
@@ -1002,7 +1002,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 	      goto trace1;
 	    }
 
-	  if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto1 == NAT_PROTOCOL_ICMP))
 	    {
 	      next1 = icmp_out2in_slow_path
 		(sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
@@ -1031,7 +1031,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 		   * be able to use dhcp client on the outside interface
 		   */
 		  if (PREDICT_FALSE
-		      (proto1 == SNAT_PROTOCOL_UDP
+		      (proto1 == NAT_PROTOCOL_UDP
 		       && (vnet_buffer (b1)->ip.reass.l4_dst_port ==
 			   clib_host_to_net_u16
 			   (UDP_DST_PORT_dhcp_to_client))))
@@ -1077,7 +1077,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 				 dst_address /* changed member */ );
 	  ip1->checksum = ip_csum_fold (sum1);
 
-	  if (PREDICT_TRUE (proto1 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto1 == NAT_PROTOCOL_TCP))
 	    {
 	      if (!vnet_buffer (b1)->ip.reass.is_non_first_fragment)
 		{
@@ -1190,9 +1190,9 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 	  rx_fib_index0 = vec_elt (sm->ip4_main->fib_index_by_sw_if_index,
 				   sw_if_index0);
 
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    {
 	      if (nat_out2in_sm_unknown_proto (sm, b0, ip0, rx_fib_index0))
 		{
@@ -1217,7 +1217,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 	      goto trace00;
 	    }
 
-	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 	    {
 	      next0 = icmp_out2in_slow_path
 		(sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
@@ -1246,7 +1246,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 		   * be able to use dhcp client on the outside interface
 		   */
 		  if (PREDICT_FALSE
-		      (proto0 == SNAT_PROTOCOL_UDP
+		      (proto0 == NAT_PROTOCOL_UDP
 		       && (vnet_buffer (b0)->ip.reass.l4_dst_port ==
 			   clib_host_to_net_u16
 			   (UDP_DST_PORT_dhcp_to_client))))
@@ -1292,7 +1292,7 @@ VLIB_NODE_FN (snat_out2in_node) (vlib_main_t * vm,
 				 dst_address /* changed member */ );
 	  ip0->checksum = ip_csum_fold (sum0);
 
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 		{
@@ -1472,12 +1472,12 @@ VLIB_NODE_FN (snat_out2in_fast_node) (vlib_main_t * vm,
 	      goto trace00;
 	    }
 
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    goto trace00;
 
-	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 	    {
 	      next0 = icmp_out2in (sm, b0, ip0, icmp0, sw_if_index0,
 				   rx_fib_index0, node, next0, ~0, 0, 0);
@@ -1511,7 +1511,7 @@ VLIB_NODE_FN (snat_out2in_fast_node) (vlib_main_t * vm,
 	      old_port0 = udp0->dst_port;
 	      udp0->dst_port = new_port0;
 
-	      if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	      if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 		{
 		  sum0 = tcp0->checksum;
 		  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
@@ -1536,7 +1536,7 @@ VLIB_NODE_FN (snat_out2in_fast_node) (vlib_main_t * vm,
 	    }
 	  else
 	    {
-	      if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	      if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 		{
 		  sum0 = tcp0->checksum;
 		  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
diff --git a/src/plugins/nat/out2in_ed.c b/src/plugins/nat/out2in_ed.c
index a30ffd972d1..9db82e00ab4 100644
--- a/src/plugins/nat/out2in_ed.c
+++ b/src/plugins/nat/out2in_ed.c
@@ -122,7 +122,7 @@ nat44_o2i_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg)
 	}
       else
 	{
-	  proto = snat_proto_to_ip_proto (s->in2out.protocol);
+	  proto = nat_proto_to_ip_proto (s->in2out.protocol);
 	  l_port = s->in2out.port;
 	  r_port = s->ext_host_port;
 	}
@@ -228,7 +228,7 @@ create_session_for_static_mapping_ed (snat_main_t * sm,
   udp = ip4_next_header (ip);
 
   s->ext_host_addr.as_u32 = ip->src_address.as_u32;
-  s->ext_host_port = e_key.protocol == SNAT_PROTOCOL_ICMP ? 0 : udp->src_port;
+  s->ext_host_port = e_key.protocol == NAT_PROTOCOL_ICMP ? 0 : udp->src_port;
   s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
   if (lb_nat)
     s->flags |= SNAT_SESSION_FLAG_LOAD_BALANCING;
@@ -376,7 +376,7 @@ create_bypass_for_fwd (snat_main_t * sm, vlib_buffer_t * b, ip4_header_t * ip,
 	  return;
 	}
 
-      proto = ip_proto_to_snat_proto (ip->protocol);
+      proto = ip_proto_to_nat_proto (ip->protocol);
 
       s->ext_host_addr = ip->src_address;
       s->ext_host_port = r_port;
@@ -384,7 +384,7 @@ create_bypass_for_fwd (snat_main_t * sm, vlib_buffer_t * b, ip4_header_t * ip,
       s->out2in.addr = ip->dst_address;
       s->out2in.port = l_port;
       s->out2in.protocol = proto;
-      if (proto == ~0)
+      if (proto == NAT_PROTOCOL_OTHER)
 	{
 	  s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
 	  s->out2in.port = ip->protocol;
@@ -456,7 +456,7 @@ icmp_match_out2in_ed (snat_main_t * sm, vlib_node_runtime_t * node,
       /* Try to match static mapping */
       e_key.addr = ip->dst_address;
       e_key.port = l_port;
-      e_key.protocol = ip_proto_to_snat_proto (ip->protocol);
+      e_key.protocol = ip_proto_to_nat_proto (ip->protocol);
       e_key.fib_index = rx_fib_index;
       if (snat_static_mapping_match
 	  (sm, e_key, &l_key, 1, &is_addr_only, 0, 0, 0, &identity_nat))
@@ -713,15 +713,15 @@ nat44_ed_out2in_fast_path_node_fn_inline (vlib_main_t * vm,
 
 	  udp0 = ip4_next_header (ip0);
 	  tcp0 = (tcp_header_t *) udp0;
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    {
 	      next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 	      goto trace0;
 	    }
 
-	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 	    {
 	      next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 	      goto trace0;
@@ -784,7 +784,7 @@ nat44_ed_out2in_fast_path_node_fn_inline (vlib_main_t * vm,
 
 	  old_port0 = vnet_buffer (b0)->ip.reass.l4_dst_port;
 
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 		{
@@ -988,9 +988,9 @@ nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
 	  udp0 = ip4_next_header (ip0);
 	  tcp0 = (tcp_header_t *) udp0;
 	  icmp0 = (icmp46_header_t *) udp0;
-	  proto0 = ip_proto_to_snat_proto (ip0->protocol);
+	  proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-	  if (PREDICT_FALSE (proto0 == ~0))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
 	    {
 	      s0 =
 		nat44_ed_out2in_unknown_proto (sm, b0, ip0, rx_fib_index0,
@@ -1004,7 +1004,7 @@ nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
 	      goto trace0;
 	    }
 
-	  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+	  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
 	    {
 	      next0 = icmp_out2in_ed_slow_path
 		(sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
@@ -1049,7 +1049,7 @@ nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
 		   * Send DHCP packets to the ipv4 stack, or we won't
 		   * be able to use dhcp client on the outside interface
 		   */
-		  if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_UDP
+		  if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_UDP
 				     && (vnet_buffer (b0)->ip.
 					 reass.l4_dst_port ==
 					 clib_host_to_net_u16
@@ -1087,7 +1087,7 @@ nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
 	      if (PREDICT_FALSE (identity_nat0))
 		goto trace0;
 
-	      if ((proto0 == SNAT_PROTOCOL_TCP)
+	      if ((proto0 == NAT_PROTOCOL_TCP)
 		  && !tcp_flags_is_init (vnet_buffer (b0)->ip.
 					 reass.icmp_type_or_tcp_flags))
 		{
@@ -1125,7 +1125,7 @@ nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
 
 	  old_port0 = vnet_buffer (b0)->ip.reass.l4_dst_port;
 
-	  if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+	  if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
 	    {
 	      if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
 		{
diff --git a/src/plugins/nat/test/test_nat.py b/src/plugins/nat/test/test_nat.py
index 1cddc405f07..a8e2af763d0 100644
--- a/src/plugins/nat/test/test_nat.py
+++ b/src/plugins/nat/test/test_nat.py
@@ -38,7 +38,7 @@ class Event(Packet):
     fields_desc = [ByteEnumField("event_type", None,
                                  {1: "add", 2: "del", 3: "refresh"}),
                    ByteEnumField("protocol", None,
-                                 {0: "udp", 1: "tcp", 2: "icmp"}),
+                                 {0: "other", 1: "udp", 2: "tcp", 3: "icmp"}),
                    ShortField("flags", 0),
                    IPField("in_addr", None),
                    IPField("out_addr", None),