Rework kube-proxy into LB plugin

Add support of NAT66

Change-Id: Ie6aa79078a3835f989829b9a597c448dfd2f9ea3
Signed-off-by: Hongjun Ni <hongjun.ni@intel.com>

1 files changed, 968 insertions, 301 deletions

diff --git a/src/plugins/lb/node.c b/src/plugins/lb/node.c
index 529da73bcff..e19964d2f1c 100644
--- a/src/plugins/lb/node.c
+++ b/src/plugins/lb/node.c
@@ -14,6 +14,7 @@
  */
 
 #include <lb/lb.h>
+#include <vnet/fib/ip4_fib.h>
 
 #include <vnet/gre/packet.h>
 #include <lb/lbhash.h>
@@ -22,69 +23,136 @@
  _(NONE, "no error") \
  _(PROTO_NOT_SUPPORTED, "protocol not supported")
 
-typedef enum {
+typedef enum
+{
 #define _(sym,str) LB_ERROR_##sym,
   foreach_lb_error
 #undef _
-    LB_N_ERROR,
+  LB_N_ERROR,
 } lb_error_t;
 
-static char *lb_error_strings[] = {
+static char *lb_error_strings[] =
+  {
 #define _(sym,string) string,
-    foreach_lb_error
+      foreach_lb_error
 #undef _
-};
+    };
 
-typedef struct {
+typedef struct
+{
   u32 vip_index;
   u32 as_index;
 } lb_trace_t;
 
+typedef struct
+{
+  u32 vip_index;
+
+  u32 node_port;
+} lb_nodeport_trace_t;
+
+typedef struct
+{
+  u32 vip_index;
+  u32 as_index;
+  u32 rx_sw_if_index;
+  u32 next_index;
+} lb_nat_trace_t;
+
 u8 *
 format_lb_trace (u8 * s, va_list * args)
 {
   lb_main_t *lbm = &lb_main;
-  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
-  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+  CLIB_UNUSED(vlib_main_t * vm)
+= va_arg (*args, vlib_main_t *);
+    CLIB_UNUSED(vlib_node_t * node)
+  = va_arg (*args, vlib_node_t *);
   lb_trace_t *t = va_arg (*args, lb_trace_t *);
-  if (pool_is_free_index(lbm->vips, t->vip_index)) {
-      s = format(s, "lb vip[%d]: This VIP was freed since capture\n");
-  } else {
-      s = format(s, "lb vip[%d]: %U\n", t->vip_index, format_lb_vip, &lbm->vips[t->vip_index]);
-  }
-  if (pool_is_free_index(lbm->ass, t->as_index)) {
-      s = format(s, "lb as[%d]: This AS was freed since capture\n");
-  } else {
-      s = format(s, "lb as[%d]: %U\n", t->as_index, format_lb_as, &lbm->ass[t->as_index]);
-  }
+  if (pool_is_free_index(lbm->vips, t->vip_index))
+    {
+      s = format (s, "lb vip[%d]: This VIP was freed since capture\n");
+    }
+  else
+    {
+      s = format (s, "lb vip[%d]: %U\n", t->vip_index, format_lb_vip,
+                  &lbm->vips[t->vip_index]);
+    }
+  if (pool_is_free_index(lbm->ass, t->as_index))
+    {
+      s = format (s, "lb as[%d]: This AS was freed since capture\n");
+    }
+  else
+    {
+      s = format (s, "lb as[%d]: %U\n", t->as_index, format_lb_as,
+                  &lbm->ass[t->as_index]);
+    }
   return s;
 }
 
-lb_hash_t *lb_get_sticky_table(u32 thread_index)
+u8 *
+format_lb_nat_trace (u8 * s, va_list * args)
+{
+  lb_main_t *lbm = &lb_main;
+  CLIB_UNUSED(vlib_main_t * vm)
+= va_arg (*args, vlib_main_t *);
+    CLIB_UNUSED(vlib_node_t * node)
+  = va_arg (*args, vlib_node_t *);
+  lb_nat_trace_t *t = va_arg (*args, lb_nat_trace_t *);
+
+  if (pool_is_free_index(lbm->vips, t->vip_index))
+    {
+      s = format (s, "lb vip[%d]: This VIP was freed since capture\n");
+    }
+  else
+    {
+      s = format (s, "lb vip[%d]: %U\n", t->vip_index, format_lb_vip,
+                  &lbm->vips[t->vip_index]);
+    }
+  if (pool_is_free_index(lbm->ass, t->as_index))
+    {
+      s = format (s, "lb as[%d]: This AS was freed since capture\n");
+    }
+  else
+    {
+      s = format (s, "lb as[%d]: %U\n", t->as_index, format_lb_as,
+                  &lbm->ass[t->as_index]);
+    }
+  s = format (s, "lb nat: rx_sw_if_index = %d, next_index = %d",
+              t->rx_sw_if_index, t->next_index);
+
+  return s;
+}
+
+lb_hash_t *
+lb_get_sticky_table (u32 thread_index)
 {
   lb_main_t *lbm = &lb_main;
   lb_hash_t *sticky_ht = lbm->per_cpu[thread_index].sticky_ht;
   //Check if size changed
-  if (PREDICT_FALSE(sticky_ht && (lbm->per_cpu_sticky_buckets != lb_hash_nbuckets(sticky_ht))))
+  if (PREDICT_FALSE(
+      sticky_ht && (lbm->per_cpu_sticky_buckets != lb_hash_nbuckets(sticky_ht))))
     {
       //Dereference everything in there
       lb_hash_bucket_t *b;
       u32 i;
-      lb_hash_foreach_entry(sticky_ht, b, i) {
-	vlib_refcount_add(&lbm->as_refcount, thread_index, b->value[i], -1);
-	vlib_refcount_add(&lbm->as_refcount, thread_index, 0, 1);
-      }
+      lb_hash_foreach_entry(sticky_ht, b, i)
+        {
+          vlib_refcount_add (&lbm->as_refcount, thread_index, b->value[i], -1);
+          vlib_refcount_add (&lbm->as_refcount, thread_index, 0, 1);
+        }
 
-      lb_hash_free(sticky_ht);
+      lb_hash_free (sticky_ht);
       sticky_ht = NULL;
     }
 
   //Create if necessary
-  if (PREDICT_FALSE(sticky_ht == NULL)) {
-    lbm->per_cpu[thread_index].sticky_ht = lb_hash_alloc(lbm->per_cpu_sticky_buckets, lbm->flow_timeout);
-    sticky_ht = lbm->per_cpu[thread_index].sticky_ht;
-    clib_warning("Regenerated sticky table %p", sticky_ht);
-  }
+  if (PREDICT_FALSE(sticky_ht == NULL))
+    {
+      lbm->per_cpu[thread_index].sticky_ht = lb_hash_alloc (
+          lbm->per_cpu_sticky_buckets, lbm->flow_timeout);
+      sticky_ht = lbm->per_cpu[thread_index].sticky_ht;
+      clib_warning("Regenerated sticky table %p", sticky_ht);
+    }
 
   ASSERT(sticky_ht);
 
@@ -94,19 +162,19 @@ lb_hash_t *lb_get_sticky_table(u32 thread_index)
 }
 
 u64
-lb_node_get_other_ports4(ip4_header_t *ip40)
+lb_node_get_other_ports4 (ip4_header_t *ip40)
 {
   return 0;
 }
 
 u64
-lb_node_get_other_ports6(ip6_header_t *ip60)
+lb_node_get_other_ports6 (ip6_header_t *ip60)
 {
   return 0;
 }
 
 static_always_inline u32
-lb_node_get_hash(vlib_buffer_t *p, u8 is_input_v4)
+lb_node_get_hash (vlib_buffer_t *p, u8 is_input_v4)
 {
   u32 hash;
   if (is_input_v4)
@@ -114,347 +182,946 @@ lb_node_get_hash(vlib_buffer_t *p, u8 is_input_v4)
       ip4_header_t *ip40;
       u64 ports;
       ip40 = vlib_buffer_get_current (p);
-      if (PREDICT_TRUE (ip40->protocol == IP_PROTOCOL_TCP ||
-		       ip40->protocol == IP_PROTOCOL_UDP))
-	ports = ((u64)((udp_header_t *)(ip40 + 1))->src_port << 16) |
-	  ((u64)((udp_header_t *)(ip40 + 1))->dst_port);
+      if (PREDICT_TRUE(
+          ip40->protocol == IP_PROTOCOL_TCP
+              || ip40->protocol == IP_PROTOCOL_UDP))
+        ports = ((u64) ((udp_header_t *) (ip40 + 1))->src_port << 16)
+            | ((u64) ((udp_header_t *) (ip40 + 1))->dst_port);
       else
-	ports = lb_node_get_other_ports4(ip40);
+        ports = lb_node_get_other_ports4 (ip40);
 
-      hash = lb_hash_hash(*((u64 *)&ip40->address_pair), ports,
-			  0, 0, 0);
+      hash = lb_hash_hash (*((u64 *) &ip40->address_pair), ports, 0, 0, 0);
     }
   else
     {
       ip6_header_t *ip60;
       ip60 = vlib_buffer_get_current (p);
       u64 ports;
-      if (PREDICT_TRUE (ip60->protocol == IP_PROTOCOL_TCP ||
-			ip60->protocol == IP_PROTOCOL_UDP))
-	ports = ((u64)((udp_header_t *)(ip60 + 1))->src_port << 16) |
-	((u64)((udp_header_t *)(ip60 + 1))->dst_port);
+      if (PREDICT_TRUE(
+          ip60->protocol == IP_PROTOCOL_TCP
+              || ip60->protocol == IP_PROTOCOL_UDP))
+        ports = ((u64) ((udp_header_t *) (ip60 + 1))->src_port << 16)
+            | ((u64) ((udp_header_t *) (ip60 + 1))->dst_port);
       else
-	ports = lb_node_get_other_ports6(ip60);
+        ports = lb_node_get_other_ports6 (ip60);
 
-      hash = lb_hash_hash(ip60->src_address.as_u64[0],
-			  ip60->src_address.as_u64[1],
-			  ip60->dst_address.as_u64[0],
-			  ip60->dst_address.as_u64[1],
-			  ports);
+      hash = lb_hash_hash (ip60->src_address.as_u64[0],
+                           ip60->src_address.as_u64[1],
+                           ip60->dst_address.as_u64[0],
+                           ip60->dst_address.as_u64[1], ports);
     }
   return hash;
 }
 
 static_always_inline uword
-lb_node_fn (vlib_main_t * vm,
-         vlib_node_runtime_t * node, vlib_frame_t * frame,
-         u8 is_input_v4, //Compile-time parameter stating that is input is v4 (or v6)
-	 lb_encap_type_t encap_type) //Compile-time parameter stating that is GRE4 or GRE6 or L3DSR
+lb_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame,
+            u8 is_input_v4, //Compile-time parameter stating that is input is v4 (or v6)
+            lb_encap_type_t encap_type) //Compile-time parameter is GRE4/GRE6/L3DSR/NAT4/NAT6
 {
   lb_main_t *lbm = &lb_main;
   u32 n_left_from, *from, next_index, *to_next, n_left_to_next;
-  u32 thread_index = vlib_get_thread_index();
-  u32 lb_time = lb_hash_time_now(vm);
+  u32 thread_index = vlib_get_thread_index ();
+  u32 lb_time = lb_hash_time_now (vm);
 
-  lb_hash_t *sticky_ht = lb_get_sticky_table(thread_index);
+  lb_hash_t *sticky_ht = lb_get_sticky_table (thread_index);
   from = vlib_frame_vector_args (frame);
   n_left_from = frame->n_vectors;
   next_index = node->cached_next_index;
 
   u32 nexthash0 = 0;
   if (PREDICT_TRUE(n_left_from > 0))
-    nexthash0 = lb_node_get_hash(vlib_get_buffer (vm, from[0]), is_input_v4);
+    nexthash0 = lb_node_get_hash (vlib_get_buffer (vm, from[0]), is_input_v4);
 
   while (n_left_from > 0)
-  {
-    vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
-    while (n_left_from > 0 && n_left_to_next > 0)
     {
-      u32 pi0;
-      vlib_buffer_t *p0;
-      lb_vip_t *vip0;
-      u32 asindex0;
-      u16 len0;
-      u32 available_index0;
-      u8 counter = 0;
-      u32 hash0 = nexthash0;
-
-      if (PREDICT_TRUE(n_left_from > 1))
-	{
-	  vlib_buffer_t *p1 = vlib_get_buffer (vm, from[1]);
-	  //Compute next hash and prefetch bucket
-	  nexthash0 = lb_node_get_hash(p1, is_input_v4);
-	  lb_hash_prefetch_bucket(sticky_ht, nexthash0);
-	  //Prefetch for encap, next
-	  CLIB_PREFETCH (vlib_buffer_get_current(p1) - 64, 64, STORE);
-	}
-
-      if (PREDICT_TRUE(n_left_from > 2))
-	{
-	  vlib_buffer_t *p2;
-	  p2 = vlib_get_buffer(vm, from[2]);
-	  /* prefetch packet header and data */
-	  vlib_prefetch_buffer_header(p2, STORE);
-	  CLIB_PREFETCH (vlib_buffer_get_current(p2), 64, STORE);
-	}
-
-      pi0 = to_next[0] = from[0];
-      from += 1;
-      n_left_from -= 1;
-      to_next += 1;
-      n_left_to_next -= 1;
-
-      p0 = vlib_get_buffer (vm, pi0);
-      vip0 = pool_elt_at_index (lbm->vips,
-				vnet_buffer (p0)->ip.adj_index[VLIB_TX]);
-
-      if (is_input_v4)
-	{
-	  ip4_header_t *ip40;
-	  ip40 = vlib_buffer_get_current (p0);
-	  len0 = clib_net_to_host_u16(ip40->length);
-	}
-      else
-	{
-	  ip6_header_t *ip60;
-	  ip60 = vlib_buffer_get_current (p0);
-	  len0 = clib_net_to_host_u16(ip60->payload_length) + sizeof(ip6_header_t);
-	}
-
-      lb_hash_get(sticky_ht, hash0, vnet_buffer (p0)->ip.adj_index[VLIB_TX],
-		  lb_time, &available_index0, &asindex0);
-
-      if (PREDICT_TRUE(asindex0 != ~0))
-	{
-	  //Found an existing entry
-	  counter = LB_VIP_COUNTER_NEXT_PACKET;
-	}
-      else if (PREDICT_TRUE(available_index0 != ~0))
-	{
-	  //There is an available slot for a new flow
-	  asindex0 = vip0->new_flow_table[hash0 & vip0->new_flow_table_mask].as_index;
-	  counter = LB_VIP_COUNTER_FIRST_PACKET;
-	  counter = (asindex0 == 0)?LB_VIP_COUNTER_NO_SERVER:counter;
-
-	  //TODO: There are race conditions with as0 and vip0 manipulation.
-	  //Configuration may be changed, vectors resized, etc...
-
-	  //Dereference previously used
-	  vlib_refcount_add(&lbm->as_refcount, thread_index,
-			    lb_hash_available_value(sticky_ht, hash0, available_index0), -1);
-	  vlib_refcount_add(&lbm->as_refcount, thread_index,
-			    asindex0, 1);
-
-	  //Add sticky entry
-	  //Note that when there is no AS configured, an entry is configured anyway.
-	  //But no configured AS is not something that should happen
-	  lb_hash_put(sticky_ht, hash0, asindex0,
-		      vnet_buffer (p0)->ip.adj_index[VLIB_TX],
-		      available_index0, lb_time);
-	}
-      else
-	{
-	  //Could not store new entry in the table
-	  asindex0 = vip0->new_flow_table[hash0 & vip0->new_flow_table_mask].as_index;
-	  counter = LB_VIP_COUNTER_UNTRACKED_PACKET;
-	}
-
-      vlib_increment_simple_counter(&lbm->vip_counters[counter],
-				    thread_index,
-				    vnet_buffer (p0)->ip.adj_index[VLIB_TX],
-				    1);
-
-      //Now let's encap
-      if ( (encap_type == LB_ENCAP_TYPE_GRE4)
-	   || (encap_type == LB_ENCAP_TYPE_GRE6) )
+      vlib_get_next_frame(vm, node, next_index, to_next, n_left_to_next);
+      while (n_left_from > 0 && n_left_to_next > 0)
         {
-	  gre_header_t *gre0;
-	  if (encap_type == LB_ENCAP_TYPE_GRE4) /* encap GRE4*/
-	    {
-	      ip4_header_t *ip40;
-	      vlib_buffer_advance(p0, - sizeof(ip4_header_t) - sizeof(gre_header_t));
-	      ip40 = vlib_buffer_get_current(p0);
-	      gre0 = (gre_header_t *)(ip40 + 1);
-	      ip40->src_address = lbm->ip4_src_address;
-	      ip40->dst_address = lbm->ass[asindex0].address.ip4;
-	      ip40->ip_version_and_header_length = 0x45;
-	      ip40->ttl = 128;
-	      ip40->fragment_id = 0;
-	      ip40->flags_and_fragment_offset = 0;
-	      ip40->length = clib_host_to_net_u16(len0 + sizeof(gre_header_t) + sizeof(ip4_header_t));
-	      ip40->protocol = IP_PROTOCOL_GRE;
-	      ip40->checksum = ip4_header_checksum (ip40);
-	    }
-	  else /* encap GRE6*/
-	    {
-	      ip6_header_t *ip60;
-	      vlib_buffer_advance(p0, - sizeof(ip6_header_t) - sizeof(gre_header_t));
-	      ip60 = vlib_buffer_get_current(p0);
-	      gre0 = (gre_header_t *)(ip60 + 1);
-	      ip60->dst_address = lbm->ass[asindex0].address.ip6;
-	      ip60->src_address = lbm->ip6_src_address;
-	      ip60->hop_limit = 128;
-	      ip60->ip_version_traffic_class_and_flow_label = clib_host_to_net_u32 (0x6<<28);
-	      ip60->payload_length = clib_host_to_net_u16(len0 + sizeof(gre_header_t));
-	      ip60->protocol = IP_PROTOCOL_GRE;
-	    }
-
-	  gre0->flags_and_version = 0;
-	  gre0->protocol = (is_input_v4)?
-	      clib_host_to_net_u16(0x0800):
-	      clib_host_to_net_u16(0x86DD);
-      } else if (encap_type == LB_ENCAP_TYPE_L3DSR) /* encap L3DSR*/
-	{
-	  ip4_header_t *ip40;
-	  tcp_header_t *th0;
-
-	  ip40 = vlib_buffer_get_current(p0);
-	  ip40->dst_address = lbm->ass[asindex0].address.ip4;
-	  /* Get and rewrite DSCP bit */
-          ip40->tos = (u8)((vip0->dscp & 0x3F)<<2);
-	  ip40->checksum = ip4_header_checksum (ip40);
-	  /* Recomputing L4 checksum after dst-IP modifying */
-	  th0 = ip4_next_header(ip40);
-	  th0->checksum = 0;
-	  th0->checksum = ip4_tcp_udp_compute_checksum(vm, p0, ip40);
-	}
-
-      if (PREDICT_FALSE (p0->flags & VLIB_BUFFER_IS_TRACED))
-	{
-	  lb_trace_t *tr = vlib_add_trace (vm, node, p0, sizeof (*tr));
-	  tr->as_index = asindex0;
-	  tr->vip_index = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
-	}
-
-      //Enqueue to next
-      //Note that this is going to error if asindex0 == 0
-      vnet_buffer (p0)->ip.adj_index[VLIB_TX] = lbm->ass[asindex0].dpo.dpoi_index;
-      vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
-				       n_left_to_next, pi0,
-				       lbm->ass[asindex0].dpo.dpoi_next_node);
+          u32 pi0;
+          vlib_buffer_t *p0;
+          lb_vip_t *vip0;
+          u32 asindex0;
+          u16 len0;
+          u32 available_index0;
+          u8 counter = 0;
+          u32 hash0 = nexthash0;
+
+          if (PREDICT_TRUE(n_left_from > 1))
+            {
+              vlib_buffer_t *p1 = vlib_get_buffer (vm, from[1]);
+              //Compute next hash and prefetch bucket
+              nexthash0 = lb_node_get_hash (p1, is_input_v4);
+              lb_hash_prefetch_bucket (sticky_ht, nexthash0);
+              //Prefetch for encap, next
+              CLIB_PREFETCH(vlib_buffer_get_current (p1) - 64, 64, STORE);
+            }
+
+          if (PREDICT_TRUE(n_left_from > 2))
+            {
+              vlib_buffer_t *p2;
+              p2 = vlib_get_buffer (vm, from[2]);
+              /* prefetch packet header and data */
+              vlib_prefetch_buffer_header(p2, STORE);
+              CLIB_PREFETCH(vlib_buffer_get_current (p2), 64, STORE);
+            }
+
+          pi0 = to_next[0] = from[0];
+          from += 1;
+          n_left_from -= 1;
+          to_next += 1;
+          n_left_to_next -= 1;
+
+          p0 = vlib_get_buffer (vm, pi0);
+          vip0 = pool_elt_at_index(lbm->vips,
+                                   vnet_buffer (p0)->ip.adj_index[VLIB_TX]);
+
+          if (is_input_v4)
+            {
+              ip4_header_t *ip40;
+              ip40 = vlib_buffer_get_current (p0);
+              len0 = clib_net_to_host_u16 (ip40->length);
+            }
+          else
+            {
+              ip6_header_t *ip60;
+              ip60 = vlib_buffer_get_current (p0);
+              len0 = clib_net_to_host_u16 (ip60->payload_length)
+                  + sizeof(ip6_header_t);
+            }
+
+          lb_hash_get (sticky_ht, hash0,
+                       vnet_buffer (p0)->ip.adj_index[VLIB_TX], lb_time,
+                       &available_index0, &asindex0);
+
+          if (PREDICT_TRUE(asindex0 != ~0))
+            {
+              //Found an existing entry
+              counter = LB_VIP_COUNTER_NEXT_PACKET;
+            }
+          else if (PREDICT_TRUE(available_index0 != ~0))
+            {
+              //There is an available slot for a new flow
+              asindex0 =
+                  vip0->new_flow_table[hash0 & vip0->new_flow_table_mask].as_index;
+              counter = LB_VIP_COUNTER_FIRST_PACKET;
+              counter = (asindex0 == 0) ? LB_VIP_COUNTER_NO_SERVER : counter;
+
+              //TODO: There are race conditions with as0 and vip0 manipulation.
+              //Configuration may be changed, vectors resized, etc...
+
+              //Dereference previously used
+              vlib_refcount_add (
+                  &lbm->as_refcount, thread_index,
+                  lb_hash_available_value (sticky_ht, hash0, available_index0),
+                  -1);
+              vlib_refcount_add (&lbm->as_refcount, thread_index, asindex0, 1);
+
+              //Add sticky entry
+              //Note that when there is no AS configured, an entry is configured anyway.
+              //But no configured AS is not something that should happen
+              lb_hash_put (sticky_ht, hash0, asindex0,
+              vnet_buffer (p0)->ip.adj_index[VLIB_TX],
+                           available_index0, lb_time);
+            }
+          else
+            {
+              //Could not store new entry in the table
+              asindex0 =
+                  vip0->new_flow_table[hash0 & vip0->new_flow_table_mask].as_index;
+              counter = LB_VIP_COUNTER_UNTRACKED_PACKET;
+            }
+
+          vlib_increment_simple_counter (
+              &lbm->vip_counters[counter], thread_index,
+              vnet_buffer (p0)->ip.adj_index[VLIB_TX],
+              1);
+
+          //Now let's encap
+          if ((encap_type == LB_ENCAP_TYPE_GRE4)
+              || (encap_type == LB_ENCAP_TYPE_GRE6))
+            {
+              gre_header_t *gre0;
+              if (encap_type == LB_ENCAP_TYPE_GRE4) /* encap GRE4*/
+                {
+                  ip4_header_t *ip40;
+                  vlib_buffer_advance (
+                      p0, -sizeof(ip4_header_t) - sizeof(gre_header_t));
+                  ip40 = vlib_buffer_get_current (p0);
+                  gre0 = (gre_header_t *) (ip40 + 1);
+                  ip40->src_address = lbm->ip4_src_address;
+                  ip40->dst_address = lbm->ass[asindex0].address.ip4;
+                  ip40->ip_version_and_header_length = 0x45;
+                  ip40->ttl = 128;
+                  ip40->fragment_id = 0;
+                  ip40->flags_and_fragment_offset = 0;
+                  ip40->length = clib_host_to_net_u16 (
+                      len0 + sizeof(gre_header_t) + sizeof(ip4_header_t));
+                  ip40->protocol = IP_PROTOCOL_GRE;
+                  ip40->checksum = ip4_header_checksum (ip40);
+                }
+              else /* encap GRE6*/
+                {
+                  ip6_header_t *ip60;
+                  vlib_buffer_advance (
+                      p0, -sizeof(ip6_header_t) - sizeof(gre_header_t));
+                  ip60 = vlib_buffer_get_current (p0);
+                  gre0 = (gre_header_t *) (ip60 + 1);
+                  ip60->dst_address = lbm->ass[asindex0].address.ip6;
+                  ip60->src_address = lbm->ip6_src_address;
+                  ip60->hop_limit = 128;
+                  ip60->ip_version_traffic_class_and_flow_label =
+                      clib_host_to_net_u32 (0x6 << 28);
+                  ip60->payload_length = clib_host_to_net_u16 (
+                      len0 + sizeof(gre_header_t));
+                  ip60->protocol = IP_PROTOCOL_GRE;
+                }
+
+              gre0->flags_and_version = 0;
+              gre0->protocol =
+                  (is_input_v4) ?
+                      clib_host_to_net_u16 (0x0800) :
+                      clib_host_to_net_u16 (0x86DD);
+            }
+          else if (encap_type == LB_ENCAP_TYPE_L3DSR) /* encap L3DSR*/
+            {
+              ip4_header_t *ip40;
+              tcp_header_t *th0;
+              ip_csum_t csum;
+              u32 old_dst;
+              u32 old_dscp;
+
+              ip40 = vlib_buffer_get_current (p0);
+              old_dst = ip40->dst_address.as_u32;
+              old_dscp = ip40->tos;
+              ip40->dst_address = lbm->ass[asindex0].address.ip4;
+              /* Get and rewrite DSCP bit */
+              ip40->tos = (u8) ((vip0->encap_args.dscp & 0x3F) << 2);
+
+              csum = ip40->checksum;
+              csum = ip_csum_sub_even (csum, old_dst);
+              csum = ip_csum_sub_even (csum, old_dscp);
+              csum = ip_csum_add_even (csum,
+                                       lbm->ass[asindex0].address.ip4.as_u32);
+              csum = ip_csum_add_even (csum, ip40->tos);
+              ip40->checksum = ip_csum_fold (csum);
+
+              /* Recomputing L4 checksum after dst-IP modifying */
+              th0 = ip4_next_header (ip40);
+              th0->checksum = 0;
+              th0->checksum = ip4_tcp_udp_compute_checksum (vm, p0, ip40);
+            }
+          else if ((encap_type == LB_ENCAP_TYPE_NAT4)
+              || (encap_type == LB_ENCAP_TYPE_NAT6))
+            {
+              ip_csum_t csum;
+              udp_header_t *uh;
+
+              /* do NAT */
+              if ((is_input_v4 == 1) && (encap_type == LB_ENCAP_TYPE_NAT4))
+                {
+                  /* NAT44 */
+                  ip4_header_t *ip40;
+                  u32 old_dst;
+                  ip40 = vlib_buffer_get_current (p0);
+                  uh = (udp_header_t *) (ip40 + 1);
+                  old_dst = ip40->dst_address.as_u32;
+                  ip40->dst_address = lbm->ass[asindex0].address.ip4;
+
+                  csum = ip40->checksum;
+                  csum = ip_csum_sub_even (csum, old_dst);
+                  csum = ip_csum_add_even (
+                      csum, lbm->ass[asindex0].address.ip4.as_u32);
+                  ip40->checksum = ip_csum_fold (csum);
+
+                  if ((ip40->protocol == IP_PROTOCOL_UDP)
+                      || (uh->dst_port == vip0->encap_args.port))
+                    {
+                      uh->dst_port = vip0->encap_args.target_port;
+                      csum = uh->checksum;
+                      csum = ip_csum_sub_even (csum, old_dst);
+                      csum = ip_csum_add_even (
+                          csum, lbm->ass[asindex0].address.ip4.as_u32);
+                      uh->checksum = ip_csum_fold (csum);
+                    }
+                  else
+                    {
+                      next_index = LB_NEXT_DROP;
+                    }
+                }
+              else if ((is_input_v4 == 0) && (encap_type == LB_ENCAP_TYPE_NAT6))
+                {
+                  /* NAT66 */
+                  ip6_header_t *ip60;
+                  ip6_address_t old_dst;
+
+                  ip60 = vlib_buffer_get_current (p0);
+                  uh = (udp_header_t *) (ip60 + 1);
+
+                  old_dst.as_u64[0] = ip60->dst_address.as_u64[0];
+                  old_dst.as_u64[1] = ip60->dst_address.as_u64[1];
+                  ip60->dst_address.as_u64[0] =
+                      lbm->ass[asindex0].address.ip6.as_u64[0];
+                  ip60->dst_address.as_u64[1] =
+                      lbm->ass[asindex0].address.ip6.as_u64[1];
+
+                  if (PREDICT_TRUE(ip60->protocol == IP_PROTOCOL_UDP))
+                    {
+                      uh->dst_port = vip0->encap_args.target_port;
+                      csum = uh->checksum;
+                      csum = ip_csum_sub_even (csum, old_dst.as_u64[0]);
+                      csum = ip_csum_sub_even (csum, old_dst.as_u64[1]);
+                      csum = ip_csum_add_even (
+                          csum, lbm->ass[asindex0].address.ip6.as_u64[0]);
+                      csum = ip_csum_add_even (
+                          csum, lbm->ass[asindex0].address.ip6.as_u64[1]);
+                      uh->checksum = ip_csum_fold (csum);
+                    }
+                  else
+                    {
+                      next_index = LB_NEXT_DROP;
+                    }
+                }
+            }
+
+          if (PREDICT_FALSE(p0->flags & VLIB_BUFFER_IS_TRACED))
+            {
+              lb_trace_t *tr = vlib_add_trace (vm, node, p0, sizeof(*tr));
+              tr->as_index = asindex0;
+              tr->vip_index = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
+            }
+
+          //Enqueue to next
+          //Note that this is going to error if asindex0 == 0
+          vnet_buffer (p0)->ip.adj_index[VLIB_TX] =
+              lbm->ass[asindex0].dpo.dpoi_index;
+          vlib_validate_buffer_enqueue_x1(
+              vm, node, next_index, to_next, n_left_to_next, pi0,
+              lbm->ass[asindex0].dpo.dpoi_next_node);
+        }
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
     }
-    vlib_put_next_frame (vm, node, next_index, n_left_to_next);
-  }
 
   return frame->n_vectors;
 }
 
+u8 *
+format_nodeport_lb_trace (u8 * s, va_list * args)
+{
+  lb_main_t *lbm = &lb_main;
+  CLIB_UNUSED(vlib_main_t * vm)
+= va_arg (*args, vlib_main_t *);
+    CLIB_UNUSED(vlib_node_t * node)
+  = va_arg (*args, vlib_node_t *);
+  lb_nodeport_trace_t *t = va_arg (*args, lb_nodeport_trace_t *);
+  if (pool_is_free_index(lbm->vips, t->vip_index))
+    {
+      s = format (s, "lb vip[%d]: This VIP was freed since capture\n");
+    }
+  else
+    {
+      s = format (s, "lb vip[%d]: %U\n", t->vip_index, format_lb_vip,
+                  &lbm->vips[t->vip_index]);
+    }
+
+  s = format (s, "  lb node_port: %d", t->node_port);
+
+  return s;
+}
+
 static uword
-lb6_gre6_node_fn (vlib_main_t * vm,
-         vlib_node_runtime_t * node, vlib_frame_t * frame)
+lb_nodeport_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+                     vlib_frame_t * frame, u8 is_input_v4)
 {
-  return lb_node_fn(vm, node, frame, 0, LB_ENCAP_TYPE_GRE6);
+  lb_main_t *lbm = &lb_main;
+  u32 n_left_from, *from, next_index, *to_next, n_left_to_next;
+
+  from = vlib_frame_vector_args (frame);
+  n_left_from = frame->n_vectors;
+  next_index = node->cached_next_index;
+
+  while (n_left_from > 0)
+    {
+      vlib_get_next_frame(vm, node, next_index, to_next, n_left_to_next);
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+        {
+          u32 pi0;
+          vlib_buffer_t *p0;
+          udp_header_t * udp_0;
+          uword * entry0;
+
+          if (PREDICT_TRUE(n_left_from > 1))
+            {
+              vlib_buffer_t *p1 = vlib_get_buffer (vm, from[1]);
+              //Prefetch for encap, next
+              CLIB_PREFETCH(vlib_buffer_get_current (p1) - 64, 64, STORE);
+            }
+
+          if (PREDICT_TRUE(n_left_from > 2))
+            {
+              vlib_buffer_t *p2;
+              p2 = vlib_get_buffer (vm, from[2]);
+              /* prefetch packet header and data */
+              vlib_prefetch_buffer_header(p2, STORE);
+              CLIB_PREFETCH(vlib_buffer_get_current (p2), 64, STORE);
+            }
+
+          pi0 = to_next[0] = from[0];
+          from += 1;
+          n_left_from -= 1;
+          to_next += 1;
+          n_left_to_next -= 1;
+
+          p0 = vlib_get_buffer (vm, pi0);
+
+          if (is_input_v4)
+            {
+              ip4_header_t *ip40;
+              vlib_buffer_advance (
+                  p0, -(word) (sizeof(udp_header_t) + sizeof(ip4_header_t)));
+              ip40 = vlib_buffer_get_current (p0);
+              udp_0 = (udp_header_t *) (ip40 + 1);
+            }
+          else
+            {
+              ip6_header_t *ip60;
+              vlib_buffer_advance (
+                  p0, -(word) (sizeof(udp_header_t) + sizeof(ip6_header_t)));
+              ip60 = vlib_buffer_get_current (p0);
+              udp_0 = (udp_header_t *) (ip60 + 1);
+            }
+
+          entry0 = hash_get_mem(lbm->vip_index_by_nodeport, &(udp_0->dst_port));
+
+          //Enqueue to next
+          vnet_buffer(p0)->ip.adj_index[VLIB_TX] = entry0[0];
+
+          if (PREDICT_FALSE(p0->flags & VLIB_BUFFER_IS_TRACED))
+            {
+              lb_nodeport_trace_t *tr = vlib_add_trace (vm, node, p0,
+                                                        sizeof(*tr));
+              tr->vip_index = entry0[0];
+              tr->node_port = (u32) clib_net_to_host_u16 (udp_0->dst_port);
+            }
+
+          vlib_validate_buffer_enqueue_x1(vm, node, next_index, to_next,
+              n_left_to_next, pi0,
+              is_input_v4 ?
+                  LB4_NODEPORT_NEXT_IP4_NAT4 : LB6_NODEPORT_NEXT_IP6_NAT6);
+        }
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  return frame->n_vectors;
+
+}
+
+/**
+ * @brief Match NAT44 static mapping.
+ *
+ * @param sm          NAT main.
+ * @param match       Address and port to match.
+ * @param index       index to the pool.
+ *
+ * @returns 0 if match found, otherwise -1.
+ */
+int
+lb_nat44_mapping_match (lb_main_t *lbm, lb_snat4_key_t * match, u32 *index)
+{
+  clib_bihash_kv_8_8_t kv4, value;
+  clib_bihash_8_8_t *mapping_hash = &lbm->mapping_by_as4;
+
+  kv4.key = match->as_u64;
+  kv4.value = 0;
+  if (clib_bihash_search_8_8 (mapping_hash, &kv4, &value))
+    {
+      return 1;
+    }
+
+  *index = value.value;
+  return 0;
+}
+
+/**
+ * @brief Match NAT66 static mapping.
+ *
+ * @param sm          NAT main.
+ * @param match       Address and port to match.
+ * @param mapping     External or local address and port of the matched mapping.
+ *
+ * @returns 0 if match found otherwise 1.
+ */
+int
+lb_nat66_mapping_match (lb_main_t *lbm, lb_snat6_key_t * match, u32 *index)
+{
+  clib_bihash_kv_24_8_t kv6, value;
+  lb_snat6_key_t m_key6;
+  clib_bihash_24_8_t *mapping_hash = &lbm->mapping_by_as6;
+
+  m_key6.addr.as_u64[0] = match->addr.as_u64[0];
+  m_key6.addr.as_u64[1] = match->addr.as_u64[1];
+  m_key6.port = match->port;
+  m_key6.protocol = 0;
+  m_key6.fib_index = 0;
+
+  kv6.key[0] = m_key6.as_u64[0];
+  kv6.key[1] = m_key6.as_u64[1];
+  kv6.key[2] = m_key6.as_u64[2];
+  kv6.value = 0;
+  if (clib_bihash_search_24_8 (mapping_hash, &kv6, &value))
+    {
+      return 1;
+    }
+
+  *index = value.value;
+  return 0;
+}
+
+static uword
+lb_nat_in2out_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+                       vlib_frame_t * frame, u32 is_nat4)
+{
+  u32 n_left_from, *from, *to_next;
+  u32 next_index;
+  u32 pkts_processed = 0;
+  lb_main_t *lbm = &lb_main;
+  u32 stats_node_index;
+
+  stats_node_index =
+      is_nat4 ? lb_nat4_in2out_node.index : lb_nat6_in2out_node.index;
+
+  from = vlib_frame_vector_args (frame);
+  n_left_from = frame->n_vectors;
+  next_index = node->cached_next_index;
+
+  while (n_left_from > 0)
+    {
+      u32 n_left_to_next;
+
+      vlib_get_next_frame(vm, node, next_index, to_next, n_left_to_next);
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+        {
+          u32 bi0;
+          vlib_buffer_t * b0;
+          u32 next0;
+          u32 sw_if_index0;
+          ip_csum_t csum;
+          u16 old_port0, new_port0;
+          udp_header_t * udp0;
+          tcp_header_t * tcp0;
+
+          u32 proto0;
+          u32 rx_fib_index0;
+
+          /* speculatively enqueue b0 to the current next frame */
+          bi0 = from[0];
+          to_next[0] = bi0;
+          from += 1;
+          to_next += 1;
+          n_left_from -= 1;
+          n_left_to_next -= 1;
+
+          b0 = vlib_get_buffer (vm, bi0);
+          next0 = LB_NAT4_IN2OUT_NEXT_LOOKUP;
+          sw_if_index0 = vnet_buffer(b0)->sw_if_index[VLIB_RX];
+          rx_fib_index0 = ip4_fib_table_get_index_for_sw_if_index (
+              sw_if_index0);
+
+          if (is_nat4)
+            {
+              ip4_header_t * ip40;
+              u32 old_addr0, new_addr0;
+              lb_snat4_key_t key40;
+              lb_snat_mapping_t *sm40;
+              u32 index40;
+
+              ip40 = vlib_buffer_get_current (b0);
+              udp0 = ip4_next_header (ip40);
+              tcp0 = (tcp_header_t *) udp0;
+              proto0 = lb_ip_proto_to_nat_proto (ip40->protocol);
+
+              key40.addr = ip40->src_address;
+              key40.protocol = proto0;
+              key40.port = udp0->src_port;
+              key40.fib_index = rx_fib_index0;
+
+              if (lb_nat44_mapping_match (lbm, &key40, &index40))
+                {
+                  next0 = LB_NAT4_IN2OUT_NEXT_DROP;
+                  goto trace0;
+                }
+
+              sm40 = pool_elt_at_index(lbm->snat_mappings, index40);
+              new_addr0 = sm40->src_ip.ip4.as_u32;
+              new_port0 = sm40->src_port;
+              vnet_buffer(b0)->sw_if_index[VLIB_TX] = sm40->fib_index;
+              old_addr0 = ip40->src_address.as_u32;
+              ip40->src_address.as_u32 = new_addr0;
+
+              csum = ip40->checksum;
+              csum = ip_csum_sub_even (csum, old_addr0);
+              csum = ip_csum_add_even (csum, new_addr0);
+              ip40->checksum = ip_csum_fold (csum);
+
+              if (PREDICT_TRUE(proto0 == LB_NAT_PROTOCOL_TCP))
+                {
+                  old_port0 = tcp0->src_port;
+                  tcp0->src_port = new_port0;
+
+                  csum = tcp0->checksum;
+                  csum = ip_csum_sub_even (csum, old_addr0);
+                  csum = ip_csum_sub_even (csum, old_port0);
+                  csum = ip_csum_add_even (csum, new_addr0);
+                  csum = ip_csum_add_even (csum, new_port0);
+                  tcp0->checksum = ip_csum_fold (csum);
+                }
+              else if (PREDICT_TRUE(proto0 == LB_NAT_PROTOCOL_UDP))
+                {
+                  old_port0 = udp0->src_port;
+                  udp0->src_port = new_port0;
+
+                  csum = udp0->checksum;
+                  csum = ip_csum_sub_even (csum, old_addr0);
+                  csum = ip_csum_sub_even (csum, old_port0);
+                  csum = ip_csum_add_even (csum, new_addr0);
+                  csum = ip_csum_add_even (csum, new_port0);
+                  udp0->checksum = ip_csum_fold (csum);
+                }
+
+              pkts_processed += next0 != LB_NAT4_IN2OUT_NEXT_DROP;
+            }
+          else
+            {
+              ip6_header_t * ip60;
+              ip6_address_t old_addr0, new_addr0;
+              lb_snat6_key_t key60;
+              lb_snat_mapping_t *sm60;
+              u32 index60;
+
+              ip60 = vlib_buffer_get_current (b0);
+              udp0 = ip6_next_header (ip60);
+              tcp0 = (tcp_header_t *) udp0;
+              proto0 = lb_ip_proto_to_nat_proto (ip60->protocol);
+
+              key60.addr.as_u64[0] = ip60->src_address.as_u64[0];
+              key60.addr.as_u64[1] = ip60->src_address.as_u64[1];
+              key60.protocol = proto0;
+              key60.port = udp0->src_port;
+              key60.fib_index = rx_fib_index0;
+
+              if (lb_nat66_mapping_match (lbm, &key60, &index60))
+                {
+                  next0 = LB_NAT6_IN2OUT_NEXT_DROP;
+                  goto trace0;
+                }
+
+              sm60 = pool_elt_at_index(lbm->snat_mappings, index60);
+              new_addr0.as_u64[0] = sm60->src_ip.as_u64[0];
+              new_addr0.as_u64[1] = sm60->src_ip.as_u64[1];
+              new_port0 = sm60->src_port;
+              vnet_buffer(b0)->sw_if_index[VLIB_TX] = sm60->fib_index;
+              old_addr0.as_u64[0] = ip60->src_address.as_u64[0];
+              old_addr0.as_u64[1] = ip60->src_address.as_u64[1];
+              ip60->src_address.as_u64[0] = new_addr0.as_u64[0];
+              ip60->src_address.as_u64[1] = new_addr0.as_u64[1];
+
+              if (PREDICT_TRUE(proto0 == LB_NAT_PROTOCOL_TCP))
+                {
+                  old_port0 = tcp0->src_port;
+                  tcp0->src_port = new_port0;
+
+                  csum = tcp0->checksum;
+                  csum = ip_csum_sub_even (csum, old_addr0.as_u64[0]);
+                  csum = ip_csum_sub_even (csum, old_addr0.as_u64[1]);
+                  csum = ip_csum_add_even (csum, new_addr0.as_u64[0]);
+                  csum = ip_csum_add_even (csum, new_addr0.as_u64[1]);
+                  csum = ip_csum_sub_even (csum, old_port0);
+                  csum = ip_csum_add_even (csum, new_port0);
+                  tcp0->checksum = ip_csum_fold (csum);
+                }
+              else if (PREDICT_TRUE(proto0 == LB_NAT_PROTOCOL_UDP))
+                {
+                  old_port0 = udp0->src_port;
+                  udp0->src_port = new_port0;
+
+                  csum = udp0->checksum;
+                  csum = ip_csum_sub_even (csum, old_addr0.as_u64[0]);
+                  csum = ip_csum_sub_even (csum, old_addr0.as_u64[1]);
+                  csum = ip_csum_add_even (csum, new_addr0.as_u64[0]);
+                  csum = ip_csum_add_even (csum, new_addr0.as_u64[1]);
+                  csum = ip_csum_sub_even (csum, old_port0);
+                  csum = ip_csum_add_even (csum, new_port0);
+                  udp0->checksum = ip_csum_fold (csum);
+                }
+
+              pkts_processed += next0 != LB_NAT4_IN2OUT_NEXT_DROP;
+            }
+
+          trace0: if (PREDICT_FALSE(
+              (node->flags & VLIB_NODE_FLAG_TRACE) && (b0->flags & VLIB_BUFFER_IS_TRACED)))
+            {
+              lb_nat_trace_t *t = vlib_add_trace (vm, node, b0, sizeof(*t));
+              t->rx_sw_if_index = sw_if_index0;
+              t->next_index = next0;
+            }
+
+          /* verify speculative enqueue, maybe switch current next frame */
+          vlib_validate_buffer_enqueue_x1(vm, node, next_index, to_next,
+                                          n_left_to_next, bi0, next0);
+        }
+
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  vlib_node_increment_counter (vm, stats_node_index,
+                               LB_NAT_IN2OUT_ERROR_IN2OUT_PACKETS,
+                               pkts_processed);
+  return frame->n_vectors;
 }
 
 static uword
-lb6_gre4_node_fn (vlib_main_t * vm,
-         vlib_node_runtime_t * node, vlib_frame_t * frame)
+lb6_gre6_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+                  vlib_frame_t * frame)
 {
-  return lb_node_fn(vm, node, frame, 0, LB_ENCAP_TYPE_GRE4);
+  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_GRE6);
 }
 
 static uword
-lb4_gre6_node_fn (vlib_main_t * vm,
-         vlib_node_runtime_t * node, vlib_frame_t * frame)
+lb6_gre4_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+                  vlib_frame_t * frame)
 {
-  return lb_node_fn(vm, node, frame, 1, LB_ENCAP_TYPE_GRE6);
+  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_GRE4);
 }
 
 static uword
-lb4_gre4_node_fn (vlib_main_t * vm,
-         vlib_node_runtime_t * node, vlib_frame_t * frame)
+lb4_gre6_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+                  vlib_frame_t * frame)
 {
-  return lb_node_fn(vm, node, frame, 1, LB_ENCAP_TYPE_GRE4);
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_GRE6);
 }
 
 static uword
-lb4_l3dsr_node_fn (vlib_main_t * vm,
-         vlib_node_runtime_t * node, vlib_frame_t * frame)
+lb4_gre4_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+                  vlib_frame_t * frame)
 {
-  return lb_node_fn(vm, node, frame, 1, LB_ENCAP_TYPE_L3DSR);
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_GRE4);
 }
 
-VLIB_REGISTER_NODE (lb6_gre6_node) =
+static uword
+lb4_l3dsr_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+                   vlib_frame_t * frame)
 {
-  .function = lb6_gre6_node_fn,
-  .name = "lb6-gre6",
-  .vector_size = sizeof (u32),
-  .format_trace = format_lb_trace,
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_L3DSR);
+}
 
-  .n_errors = LB_N_ERROR,
-  .error_strings = lb_error_strings,
+static uword
+lb6_nat6_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+                  vlib_frame_t * frame)
+{
+  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_NAT6);
+}
 
-  .n_next_nodes = LB_N_NEXT,
-  .next_nodes =
-  {
-      [LB_NEXT_DROP] = "error-drop"
-  },
-};
+static uword
+lb4_nat4_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+                  vlib_frame_t * frame)
+{
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_NAT4);
+}
 
-VLIB_REGISTER_NODE (lb6_gre4_node) =
+static uword
+lb_nat4_in2out_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+                        vlib_frame_t * frame)
 {
-  .function = lb6_gre4_node_fn,
-  .name = "lb6-gre4",
-  .vector_size = sizeof (u32),
-  .format_trace = format_lb_trace,
+  return lb_nat_in2out_node_fn (vm, node, frame, 1);
+}
+
+static uword
+lb_nat6_in2out_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+                        vlib_frame_t * frame)
+{
+  return lb_nat_in2out_node_fn (vm, node, frame, 0);
+}
 
-  .n_errors = LB_N_ERROR,
-  .error_strings = lb_error_strings,
+VLIB_REGISTER_NODE (lb6_gre6_node) =
+  {
+    .function = lb6_gre6_node_fn,
+    .name = "lb6-gre6",
+    .vector_size = sizeof(u32),
+    .format_trace = format_lb_trace,
+    .n_errors = LB_N_ERROR, .error_strings = lb_error_strings,
+    .n_next_nodes = LB_N_NEXT,
+    .next_nodes =
+        { [LB_NEXT_DROP] = "error-drop" },
+  };
 
-  .n_next_nodes = LB_N_NEXT,
-  .next_nodes =
+VLIB_REGISTER_NODE (lb6_gre4_node) =
   {
-      [LB_NEXT_DROP] = "error-drop"
-  },
-};
+    .function = lb6_gre4_node_fn,
+    .name = "lb6-gre4",
+    .vector_size = sizeof(u32),
+    .format_trace = format_lb_trace,
+    .n_errors = LB_N_ERROR,
+    .error_strings = lb_error_strings,
+    .n_next_nodes = LB_N_NEXT,
+    .next_nodes =
+        { [LB_NEXT_DROP] = "error-drop" },
+  };
 
 VLIB_REGISTER_NODE (lb4_gre6_node) =
-{
-  .function = lb4_gre6_node_fn,
-  .name = "lb4-gre6",
-  .vector_size = sizeof (u32),
-  .format_trace = format_lb_trace,
+  {
+    .function = lb4_gre6_node_fn,
+    .name = "lb4-gre6",
+    .vector_size = sizeof(u32),
+    .format_trace = format_lb_trace,
+    .n_errors = LB_N_ERROR,
+    .error_strings = lb_error_strings,
+    .n_next_nodes = LB_N_NEXT,
+    .next_nodes =
+        { [LB_NEXT_DROP] = "error-drop" }, 
+  };
+
+VLIB_REGISTER_NODE (lb4_gre4_node) =
+  {
+    .function = lb4_gre4_node_fn,
+    .name = "lb4-gre4",
+    .vector_size = sizeof(u32),
+    .format_trace = format_lb_trace,
+    .n_errors = LB_N_ERROR,
+    .error_strings = lb_error_strings,
+    .n_next_nodes = LB_N_NEXT, 
+    .next_nodes =
+        { [LB_NEXT_DROP] = "error-drop" },
+  };
 
-  .n_errors = LB_N_ERROR,
-  .error_strings = lb_error_strings,
+VLIB_REGISTER_NODE (lb4_l3dsr_node) =
+  {
+    .function = lb4_l3dsr_node_fn,
+    .name = "lb4-l3dsr",
+    .vector_size = sizeof(u32),
+    .format_trace = format_lb_trace,
+    .n_errors = LB_N_ERROR,
+    .error_strings = lb_error_strings,
+    .n_next_nodes = LB_N_NEXT,
+    .next_nodes =
+        { [LB_NEXT_DROP] = "error-drop" },
+  };
 
-  .n_next_nodes = LB_N_NEXT,
-  .next_nodes =
+VLIB_REGISTER_NODE (lb6_nat6_node) =
   {
-      [LB_NEXT_DROP] = "error-drop"
-  },
-};
+    .function = lb6_nat6_node_fn,
+    .name = "lb6-nat6",
+    .vector_size = sizeof(u32),
+    .format_trace = format_lb_trace,
+    .n_errors = LB_N_ERROR,
+    .error_strings = lb_error_strings,
+    .n_next_nodes = LB_N_NEXT,
+    .next_nodes =
+        { [LB_NEXT_DROP] = "error-drop" },
+  };
 
-VLIB_REGISTER_NODE (lb4_gre4_node) =
+VLIB_REGISTER_NODE (lb4_nat4_node) =
+  {
+    .function = lb4_nat4_node_fn,
+    .name = "lb4-nat4",
+    .vector_size = sizeof(u32),
+    .format_trace = format_lb_trace,
+    .n_errors = LB_N_ERROR,
+    .error_strings = lb_error_strings,
+    .n_next_nodes = LB_N_NEXT,
+    .next_nodes =
+        { [LB_NEXT_DROP] = "error-drop" },
+  };
+
+static uword
+lb4_nodeport_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+                      vlib_frame_t * frame)
 {
-  .function = lb4_gre4_node_fn,
-  .name = "lb4-gre4",
-  .vector_size = sizeof (u32),
-  .format_trace = format_lb_trace,
+  return lb_nodeport_node_fn (vm, node, frame, 1);
+}
 
-  .n_errors = LB_N_ERROR,
-  .error_strings = lb_error_strings,
+static uword
+lb6_nodeport_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+                      vlib_frame_t * frame)
+{
+  return lb_nodeport_node_fn (vm, node, frame, 0);
+}
 
-  .n_next_nodes = LB_N_NEXT,
-  .next_nodes =
+VLIB_REGISTER_NODE (lb4_nodeport_node) =
   {
-      [LB_NEXT_DROP] = "error-drop"
-  },
-};
+    .function = lb4_nodeport_node_fn,
+    .name = "lb4-nodeport",
+    .vector_size = sizeof(u32),
+    .format_trace = format_nodeport_lb_trace,
+    .n_errors = LB_N_ERROR,
+    .error_strings = lb_error_strings,
+    .n_next_nodes = LB4_NODEPORT_N_NEXT,
+    .next_nodes =
+        {
+            [LB4_NODEPORT_NEXT_IP4_NAT4] = "lb4-nat4",
+            [LB4_NODEPORT_NEXT_DROP] = "error-drop",
+        },
+  };
 
-VLIB_REGISTER_NODE (lb4_l3dsr_node) =
-{
-  .function = lb4_l3dsr_node_fn,
-  .name = "lb4-l3dsr",
-  .vector_size = sizeof (u32),
-  .format_trace = format_lb_trace,
+VLIB_REGISTER_NODE (lb6_nodeport_node) =
+  {
+    .function = lb6_nodeport_node_fn,
+    .name = "lb6-nodeport",
+    .vector_size = sizeof(u32),
+    .format_trace = format_nodeport_lb_trace,
+    .n_errors = LB_N_ERROR,
+    .error_strings = lb_error_strings,
+    .n_next_nodes = LB6_NODEPORT_N_NEXT,
+    .next_nodes =
+      {
+          [LB6_NODEPORT_NEXT_IP6_NAT6] = "lb6-nat6",
+          [LB6_NODEPORT_NEXT_DROP] = "error-drop",
+      },
+  };
 
-  .n_errors = LB_N_ERROR,
-  .error_strings = lb_error_strings,
+VNET_FEATURE_INIT (lb_nat4_in2out_node_fn, static) =
+  {
+    .arc_name = "ip4-unicast",
+    .node_name = "lb-nat4-in2out",
+    .runs_before =  VNET_FEATURES("ip4-lookup"),
+  };
+
+VLIB_REGISTER_NODE (lb_nat4_in2out_node) =
+  {
+    .function = lb_nat4_in2out_node_fn,
+    .name = "lb-nat4-in2out",
+    .vector_size = sizeof(u32),
+    .format_trace = format_lb_nat_trace,
+    .n_errors = LB_N_ERROR,
+    .error_strings = lb_error_strings,
+    .n_next_nodes = LB_NAT4_IN2OUT_N_NEXT,
+    .next_nodes =
+      {
+          [LB_NAT4_IN2OUT_NEXT_DROP] = "error-drop",
+          [LB_NAT4_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
+      },
+  };
 
-  .n_next_nodes = LB_N_NEXT,
-  .next_nodes =
+VNET_FEATURE_INIT (lb_nat6_in2out_node_fn, static) =
   {
-      [LB_NEXT_DROP] = "error-drop"
-  },
-};
+    .arc_name = "ip6-unicast",
+    .node_name = "lb-nat6-in2out",
+    .runs_before = VNET_FEATURES("ip6-lookup"),
+  };
+
+VLIB_REGISTER_NODE (lb_nat6_in2out_node) =
+  {
+    .function = lb_nat6_in2out_node_fn,
+    .name = "lb-nat6-in2out",
+    .vector_size = sizeof(u32),
+    .format_trace = format_lb_nat_trace,
+    .n_errors = LB_N_ERROR,
+    .error_strings = lb_error_strings,
+    .n_next_nodes = LB_NAT6_IN2OUT_N_NEXT,
+    .next_nodes =
+      {
+          [LB_NAT6_IN2OUT_NEXT_DROP] = "error-drop",
+          [LB_NAT6_IN2OUT_NEXT_LOOKUP] = "ip6-lookup",
+      },
+  };
+