Support kube-proxy data plane

This plugin provides kube-proxy data plane on user space,
which is used to replace linux kernal's kube-proxy based on iptables.
The idea is largely inspired from VPP LB plugin.

Currently, kube-proxy plugin supports three service types:
1) Cluster IP plus Port: support any protocols, including TCP, UDP.
2) Node IP plus Node Port: currently only support UDP.
3) External Load Balancer.

Please refer to kp_plugin_doc.md for details.

Change-Id: I36690e417dd26ad5ec1bd77c7ea4b8100416cac6
Signed-off-by: Hongjun Ni <hongjun.ni@intel.com>

1 files changed, 839 insertions, 0 deletions

diff --git a/src/plugins/kubeproxy/kp_node.c b/src/plugins/kubeproxy/kp_node.c
new file mode 100644
index 00000000000..5cee6971e35
--- /dev/null
+++ b/src/plugins/kubeproxy/kp_node.c
@@ -0,0 +1,839 @@
+/*
+ * Copyright (c) 2016 Intel and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or anated to in writing, software
+ * distributed under the License is distributed on an "POD IS" BPODIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+#include <vnet/fib/ip4_fib.h>
+
+#include <kubeproxy/kp.h>
+#include <kubeproxy/kphash.h>
+
+#define foreach_kp_error \
+ _(NONE, "no error") \
+ _(PROTO_NOT_SUPPORTED, "protocol not supported")
+
+typedef enum {
+#define _(sym,str) KP_ERROR_##sym,
+  foreach_kp_error
+#undef _
+    KP_N_ERROR,
+} kp_error_t;
+
+static char *kp_error_strings[] = {
+#define _(sym,string) string,
+    foreach_kp_error
+#undef _
+};
+
+typedef struct {
+  u32 vip_index;
+  u32 pod_index;
+} kp_trace_t;
+
+typedef struct {
+  u32 vip_index;
+  u32 node_port;
+} kp_nodeport_trace_t;
+
+typedef struct {
+  u32 rx_sw_if_index;
+  u32 next_index;
+} kp_nat_trace_t;
+
+u8 *
+format_kp_trace (u8 * s, va_list * args)
+{
+  kp_main_t *kpm = &kp_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 *);
+  kp_trace_t *t = va_arg (*args, kp_trace_t *);
+  if (pool_is_free_index(kpm->vips, t->vip_index)) {
+      s = format(s, "kp vip[%d]: This VIP was freed since capture\n");
+  } else {
+      s = format(s, "kp vip[%d]: %U\n", t->vip_index, format_kp_vip, &kpm->vips[t->vip_index]);
+  }
+  if (pool_is_free_index(kpm->pods, t->pod_index)) {
+      s = format(s, "  kp pod[%d]: This POD was freed since capture");
+  } else {
+      s = format(s, "  kp pod[%d]: %U", t->pod_index, format_kp_pod, &kpm->pods[t->pod_index]);
+  }
+  return s;
+}
+
+u8 *
+format_kp_nat_trace (u8 * s, va_list * args)
+{
+  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+  kp_nat_trace_t *t = va_arg (*args, kp_nat_trace_t *);
+
+  s = format(s, "kp nat: rx_sw_if_index = %d, next_index = %d",
+	     t->rx_sw_if_index, t->next_index);
+
+  return s;
+}
+
+kp_hash_t *kp_get_sticky_table(u32 thread_index)
+{
+  kp_main_t *kpm = &kp_main;
+  kp_hash_t *sticky_ht = kpm->per_cpu[thread_index].sticky_ht;
+  //Check if size changed
+  if (PREDICT_FALSE(sticky_ht && (kpm->per_cpu_sticky_buckets != kp_hash_nbuckets(sticky_ht))))
+    {
+      //Dereference everything in there
+      kp_hash_bucket_t *b;
+      u32 i;
+      kp_hash_foreach_entry(sticky_ht, b, i) {
+	vlib_refcount_add(&kpm->pod_refcount, thread_index, b->value[i], -1);
+	vlib_refcount_add(&kpm->pod_refcount, thread_index, 0, 1);
+      }
+
+      kp_hash_free(sticky_ht);
+      sticky_ht = NULL;
+    }
+
+  //Create if necessary
+  if (PREDICT_FALSE(sticky_ht == NULL)) {
+    kpm->per_cpu[thread_index].sticky_ht = kp_hash_alloc(kpm->per_cpu_sticky_buckets, kpm->flow_timeout);
+    sticky_ht = kpm->per_cpu[thread_index].sticky_ht;
+    clib_warning("Regenerated sticky table %p", sticky_ht);
+  }
+
+  ASSERT(sticky_ht);
+
+  //Update timeout
+  sticky_ht->timeout = kpm->flow_timeout;
+  return sticky_ht;
+}
+
+u64
+kp_node_get_other_ports4(ip4_header_t *ip40)
+{
+  return 0;
+}
+
+u64
+kp_node_get_other_ports6(ip6_header_t *ip60)
+{
+  return 0;
+}
+
+static_always_inline u32
+kp_node_get_hash(vlib_buffer_t *p, u8 is_input_v4)
+{
+  u32 hash;
+  if (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);
+      else
+	ports = kp_node_get_other_ports4(ip40);
+
+      hash = kp_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);
+      else
+	ports = kp_node_get_other_ports6(ip60);
+
+      hash = kp_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
+kp_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)
+         u8 is_nat_v4) //Compile-time parameter stating that is NAT is v4 (or v6)
+{
+  kp_main_t *kpm = &kp_main;
+  u32 n_left_from, *from, next_index, *to_next, n_left_to_next;
+  u32 thread_index = vlib_get_thread_index();
+  u32 kp_time = kp_hash_time_now(vm);
+
+  kp_hash_t *sticky_ht = kp_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 = kp_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;
+      kp_vip_t *vip0;
+      u32 podindex0;
+      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 = kp_node_get_hash(p1, is_input_v4);
+	  kp_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 (kpm->vips,
+				vnet_buffer (p0)->ip.adj_index[VLIB_TX]);
+
+      kp_hash_get(sticky_ht, hash0, vnet_buffer (p0)->ip.adj_index[VLIB_TX],
+		  kp_time, &available_index0, &podindex0);
+
+      if (PREDICT_TRUE(podindex0 != ~0))
+	{
+	  //Found an existing entry
+	  counter = KP_VIP_COUNTER_NEXT_PACKET;
+	}
+      else if (PREDICT_TRUE(available_index0 != ~0))
+	{
+	  //There is an available slot for a new flow
+	  podindex0 = vip0->new_flow_table[hash0 & vip0->new_flow_table_mask].pod_index;
+	  counter = KP_VIP_COUNTER_FIRST_PACKET;
+	  counter = (podindex0 == 0)?KP_VIP_COUNTER_NO_SERVER:counter;
+
+	  //Dereference previously used
+	  vlib_refcount_add(&kpm->pod_refcount, thread_index,
+			    kp_hash_available_value(sticky_ht, hash0, available_index0), -1);
+	  vlib_refcount_add(&kpm->pod_refcount, thread_index,
+			    podindex0, 1);
+
+	  //Add sticky entry
+	  //Note that when there is no POD configured, an entry is configured anyway.
+	  //But no configured POD is not something that should happen
+	  kp_hash_put(sticky_ht, hash0, podindex0,
+		      vnet_buffer (p0)->ip.adj_index[VLIB_TX],
+		      available_index0, kp_time);
+	}
+      else
+	{
+	  //Could not store new entry in the table
+	  podindex0 = vip0->new_flow_table[hash0 & vip0->new_flow_table_mask].pod_index;
+	  counter = KP_VIP_COUNTER_UNTRACKED_PACKET;
+	}
+
+      vlib_increment_simple_counter(&kpm->vip_counters[counter],
+				    thread_index,
+				    vnet_buffer (p0)->ip.adj_index[VLIB_TX],
+				    1);
+      //Now let's do NAT
+      {
+	udp_header_t *port0;
+
+	if ( (is_input_v4==1) && (is_nat_v4==1) )  /* NAT44 */
+	  {
+	    ip4_header_t *ip40;
+	    ip40 = vlib_buffer_get_current(p0);
+	    port0 = (udp_header_t *)(ip40 + 1);
+	    ip40->dst_address = kpm->pods[podindex0].address.ip4;
+	    ip40->checksum = ip4_header_checksum (ip40);
+	  }
+	else if ( (is_input_v4==1) && (is_nat_v4==0) )  /* NAT46 */
+	  {
+	    /* TBD */
+	    u16 len0 = 0;
+	    ip4_header_t *ip40;
+	    ip40 = vlib_buffer_get_current(p0);
+	    len0 = clib_net_to_host_u16(ip40->length);
+
+	    vlib_buffer_advance(p0, (-sizeof(ip6_header_t)+sizeof(ip4_header_t)) );
+	    ip6_header_t *ip60;
+	    ip60 = vlib_buffer_get_current(p0);
+	    port0 = (udp_header_t *)(ip60 + 1);
+	    ip60->payload_length = len0 - sizeof(ip4_header_t);
+	    ip60->dst_address = kpm->pods[podindex0].address.ip6;
+	  }
+	else if ( (is_input_v4==0) && (is_nat_v4==0) )  /* NAT66 */
+	  {
+	    ip6_header_t *ip60;
+	    ip60 = vlib_buffer_get_current(p0);
+	    port0 = (udp_header_t *)(ip60 + 1);
+	    ip60->dst_address = kpm->pods[podindex0].address.ip6;
+	  }
+	else /* NAT64 */
+	  {
+	    /* TBD */
+	    u16 len0 = 0;
+	    ip6_header_t *ip60;
+	    ip60 = vlib_buffer_get_current(p0);
+	    len0 = clib_net_to_host_u16(ip60->payload_length);
+
+	    vlib_buffer_advance(p0, (sizeof(ip6_header_t)-sizeof(ip4_header_t)) );
+	    ip4_header_t *ip40;
+	    ip40 = vlib_buffer_get_current(p0);
+	    port0 = (udp_header_t *)(ip40 + 1);
+	    ip40->length = len0 + sizeof(ip4_header_t);
+	    ip40->dst_address = kpm->pods[podindex0].address.ip4;
+	    ip40->checksum = ip4_header_checksum (ip40);
+	  }
+
+	port0->dst_port = vip0->target_port;
+      }
+
+      if (PREDICT_FALSE (p0->flags & VLIB_BUFFER_IS_TRACED))
+	{
+	  kp_trace_t *tr = vlib_add_trace (vm, node, p0, sizeof (*tr));
+	  tr->pod_index = podindex0;
+	  tr->vip_index = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
+	}
+
+      //Enqueue to next
+      //Note that this is going to error if podindex0 == 0
+      vnet_buffer (p0)->ip.adj_index[VLIB_TX] = kpm->pods[podindex0].dpo.dpoi_index;
+      vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
+				       n_left_to_next, pi0,
+				       kpm->pods[podindex0].dpo.dpoi_next_node);
+    }
+    vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+  }
+
+  return frame->n_vectors;
+}
+
+u8 *
+format_nodeport_kp_trace (u8 * s, va_list * args)
+{
+  kp_main_t *kpm = &kp_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 *);
+  kp_nodeport_trace_t *t = va_arg (*args, kp_nodeport_trace_t *);
+  if (pool_is_free_index(kpm->vips, t->vip_index)) {
+      s = format(s, "kp vip[%d]: This VIP was freed since capture\n");
+  } else {
+      s = format(s, "kp vip[%d]: %U\n", t->vip_index, format_kp_vip, &kpm->vips[t->vip_index]);
+  }
+
+  s = format(s, "  kp node_port: %d", t->node_port);
+
+  return s;
+}
+static uword
+kp_nodeport_node_fn (vlib_main_t * vm,
+                     vlib_node_runtime_t * node,
+		     vlib_frame_t * frame,
+		     u8 is_input_v4)
+{
+  kp_main_t *kpm = &kp_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;
+      u32 next0 = KP_NODEPORT_NEXT_DROP;
+
+
+      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==1)
+	{
+	  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(kpm->nodeport_by_key, &(udp_0->dst_port));
+
+
+      if (is_input_v4==1)
+	{
+          next0 = KP_NODEPORT_NEXT_IP4_NAT4;
+	}
+      else
+	{
+	  next0 = KP_NODEPORT_NEXT_IP6_NAT6;
+	}
+
+      if (PREDICT_FALSE (p0->flags & VLIB_BUFFER_IS_TRACED))
+	{
+	  kp_nodeport_trace_t *tr = vlib_add_trace (vm, node,
+						    p0, sizeof (*tr));
+	  tr->vip_index = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
+	  tr->node_port = (u32)clib_net_to_host_u16(udp_0->dst_port);
+	}
+
+      //Enqueue to next
+      vnet_buffer(p0)->ip.adj_index[VLIB_TX] = entry0[0];
+      vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
+				       n_left_to_next, pi0, next0);
+    }
+    vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+  }
+
+  return frame->n_vectors;
+
+}
+
+/**
+ * @brief Match NAT4 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 kp_nat4_mapping_match (kp_main_t *kpm,
+                           kp_snat4_key_t match,
+			   kp_snat4_key_t * mapping)
+{
+  clib_bihash_kv_8_8_t kv, value;
+  kp_snat_mapping_t *m;
+  kp_snat4_key_t m_key;
+  clib_bihash_8_8_t *mapping_hash = &kpm->mapping_by_pod;
+
+  m_key.addr = match.addr;
+  m_key.port = match.port;
+  m_key.protocol = match.protocol;
+  m_key.fib_index = match.fib_index;
+
+  kv.key = m_key.as_u64;
+
+  if (clib_bihash_search_8_8 (mapping_hash, &kv, &value))
+    {
+      return 1;
+    }
+
+  m = pool_elt_at_index (kpm->snat_mappings, value.value);
+
+  if (m->svr_type == KP_SVR_TYPE_VIP_PORT)
+    {
+      mapping->addr = m->vip.ip4;
+      mapping->port = clib_host_to_net_u16 (m->port);
+      mapping->fib_index = m->fib_index;
+      mapping->protocol = match.protocol;
+    }
+  else if (m->svr_type == KP_SVR_TYPE_NODEIP_PORT)
+    {
+      mapping->addr = m->node_ip.ip4;
+      mapping->port = clib_host_to_net_u16 (m->node_port);
+      mapping->fib_index = m->fib_index;
+      mapping->protocol = match.protocol;
+    }
+
+  return 0;
+}
+
+static uword
+kp_nat4_in2out_node_fn (vlib_main_t * vm,
+                        vlib_node_runtime_t * node,
+                        vlib_frame_t * frame)
+{
+  u32 n_left_from, * from, * to_next;
+  kp_nat4_in2out_next_t next_index;
+  u32 pkts_processed = 0;
+  kp_main_t *kpm = &kp_main;
+  u32 stats_node_index;
+
+  stats_node_index = kp_nat4_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;
+          ip4_header_t * ip0;
+          ip_csum_t sum0;
+          u32 new_addr0, old_addr0;
+          u16 old_port0, new_port0;
+          udp_header_t * udp0;
+          tcp_header_t * tcp0;
+          kp_snat4_key_t key0, sm0;
+          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 = KP_NAT4_IN2OUT_NEXT_LOOKUP;
+
+          ip0 = vlib_buffer_get_current (b0);
+          udp0 = ip4_next_header (ip0);
+          tcp0 = (tcp_header_t *) udp0;
+
+          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);
+
+          proto0 = kp_ip_proto_to_nat_proto (ip0->protocol);
+
+          if (PREDICT_FALSE (proto0 == ~0))
+              goto trace0;
+
+          key0.addr = ip0->src_address;
+          key0.protocol = proto0;
+          key0.port = udp0->src_port;
+          key0.fib_index = rx_fib_index0;
+
+          if (kp_nat4_mapping_match (kpm, key0, &sm0))
+            {
+              next0= KP_NAT4_IN2OUT_NEXT_DROP;
+              goto trace0;
+            }
+
+          new_addr0 = sm0.addr.as_u32;
+          new_port0 = sm0.port;
+          vnet_buffer(b0)->sw_if_index[VLIB_TX] = sm0.fib_index;
+          old_addr0 = ip0->src_address.as_u32;
+          ip0->src_address.as_u32 = new_addr0;
+
+          sum0 = ip0->checksum;
+          sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
+                                 ip4_header_t,
+                                 src_address /* changed member */);
+          ip0->checksum = ip_csum_fold (sum0);
+
+          if (PREDICT_FALSE(new_port0 != udp0->dst_port))
+            {
+              if (PREDICT_TRUE(proto0 == KP_NAT_PROTOCOL_TCP))
+                {
+                  old_port0 = tcp0->src_port;
+                  tcp0->src_port = new_port0;
+
+                  sum0 = tcp0->checksum;
+                  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
+                                         ip4_header_t,
+                                         dst_address /* changed member */);
+                  sum0 = ip_csum_update (sum0, old_port0, new_port0,
+                                         ip4_header_t /* cheat */,
+                                         length /* changed member */);
+                  tcp0->checksum = ip_csum_fold(sum0);
+                }
+              else
+                {
+                  old_port0 = udp0->src_port;
+                  udp0->src_port = new_port0;
+                  udp0->checksum = 0;
+                }
+            }
+          else
+            {
+              if (PREDICT_TRUE(proto0 == KP_NAT_PROTOCOL_TCP))
+                {
+                  sum0 = tcp0->checksum;
+                  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
+                                         ip4_header_t,
+                                         dst_address /* changed member */);
+                  tcp0->checksum = ip_csum_fold(sum0);
+                }
+            }
+
+        trace0:
+          if (PREDICT_FALSE((node->flags & VLIB_NODE_FLAG_TRACE)
+                            && (b0->flags & VLIB_BUFFER_IS_TRACED)))
+            {
+              kp_nat_trace_t *t =
+                 vlib_add_trace (vm, node, b0, sizeof (*t));
+              t->rx_sw_if_index = sw_if_index0;
+              t->next_index = next0;
+            }
+
+          pkts_processed += next0 != KP_NAT4_IN2OUT_NEXT_DROP;
+
+          /* 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,
+                               KP_NAT_IN2OUT_ERROR_IN2OUT_PACKETS,
+                               pkts_processed);
+  return frame->n_vectors;
+}
+
+static uword
+kp6_nat6_node_fn (vlib_main_t * vm,
+         vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  return kp_node_fn(vm, node, frame, 0, 0);
+}
+
+static uword
+kp6_nat4_node_fn (vlib_main_t * vm,
+         vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  return kp_node_fn(vm, node, frame, 0, 1);
+}
+
+static uword
+kp4_nat6_node_fn (vlib_main_t * vm,
+         vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  return kp_node_fn(vm, node, frame, 1, 0);
+}
+
+static uword
+kp4_nat4_node_fn (vlib_main_t * vm,
+         vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  return kp_node_fn(vm, node, frame, 1, 1);
+}
+
+VLIB_REGISTER_NODE (kp6_nat6_node) =
+{
+  .function = kp6_nat6_node_fn,
+  .name = "kp6-nat6",
+  .vector_size = sizeof (u32),
+  .format_trace = format_kp_trace,
+
+  .n_errors = KP_N_ERROR,
+  .error_strings = kp_error_strings,
+
+  .n_next_nodes = KP_N_NEXT,
+  .next_nodes =
+  {
+      [KP_NEXT_DROP] = "error-drop"
+  },
+};
+
+VLIB_REGISTER_NODE (kp6_nat4_node) =
+{
+  .function = kp6_nat4_node_fn,
+  .name = "kp6-nat4",
+  .vector_size = sizeof (u32),
+  .format_trace = format_kp_trace,
+
+  .n_errors = KP_N_ERROR,
+  .error_strings = kp_error_strings,
+
+  .n_next_nodes = KP_N_NEXT,
+  .next_nodes =
+  {
+      [KP_NEXT_DROP] = "error-drop"
+  },
+};
+
+VLIB_REGISTER_NODE (kp4_nat6_node) =
+{
+  .function = kp4_nat6_node_fn,
+  .name = "kp4-nat6",
+  .vector_size = sizeof (u32),
+  .format_trace = format_kp_trace,
+
+  .n_errors = KP_N_ERROR,
+  .error_strings = kp_error_strings,
+
+  .n_next_nodes = KP_N_NEXT,
+  .next_nodes =
+  {
+      [KP_NEXT_DROP] = "error-drop"
+  },
+};
+
+VLIB_REGISTER_NODE (kp4_nat4_node) =
+{
+  .function = kp4_nat4_node_fn,
+  .name = "kp4-nat4",
+  .vector_size = sizeof (u32),
+  .format_trace = format_kp_trace,
+
+  .n_errors = KP_N_ERROR,
+  .error_strings = kp_error_strings,
+
+  .n_next_nodes = KP_N_NEXT,
+  .next_nodes =
+  {
+      [KP_NEXT_DROP] = "error-drop"
+  },
+};
+
+static uword
+kp4_nodeport_node_fn (vlib_main_t * vm,
+                      vlib_node_runtime_t * node,
+		      vlib_frame_t * frame)
+{
+  return kp_nodeport_node_fn(vm, node, frame, 1);
+}
+
+static uword
+kp6_nodeport_node_fn (vlib_main_t * vm,
+                      vlib_node_runtime_t * node,
+		      vlib_frame_t * frame)
+{
+  return kp_nodeport_node_fn(vm, node, frame, 0);
+}
+
+VLIB_REGISTER_NODE (kp4_nodeport_node) =
+{
+  .function = kp4_nodeport_node_fn,
+  .name = "kp4-nodeport",
+  .vector_size = sizeof (u32),
+  .format_trace = format_nodeport_kp_trace,
+
+  .n_errors = KP_N_ERROR,
+  .error_strings = kp_error_strings,
+
+  .n_next_nodes = KP_NODEPORT_N_NEXT,
+  .next_nodes =
+  {
+      [KP_NODEPORT_NEXT_IP4_NAT4] = "kp4-nat4",
+      [KP_NODEPORT_NEXT_IP4_NAT6] = "kp4-nat6",
+      [KP_NODEPORT_NEXT_IP6_NAT4] = "kp6-nat4",
+      [KP_NODEPORT_NEXT_IP6_NAT6] = "kp6-nat6",
+      [KP_NODEPORT_NEXT_DROP] = "error-drop",
+  },
+};
+
+VLIB_REGISTER_NODE (kp6_nodeport_node) =
+{
+  .function = kp6_nodeport_node_fn,
+  .name = "kp6-nodeport",
+  .vector_size = sizeof (u32),
+  .format_trace = format_nodeport_kp_trace,
+
+  .n_errors = KP_N_ERROR,
+  .error_strings = kp_error_strings,
+
+  .n_next_nodes = KP_NODEPORT_N_NEXT,
+  .next_nodes =
+  {
+      [KP_NODEPORT_NEXT_IP4_NAT4] = "kp4-nat4",
+      [KP_NODEPORT_NEXT_IP4_NAT6] = "kp4-nat6",
+      [KP_NODEPORT_NEXT_IP6_NAT4] = "kp6-nat4",
+      [KP_NODEPORT_NEXT_IP6_NAT6] = "kp6-nat6",
+      [KP_NODEPORT_NEXT_DROP] = "error-drop",
+  },
+};
+
+VNET_FEATURE_INIT (kp_nat4_in2out_node_fn, static) =
+{
+  .arc_name = "ip4-unicast",
+  .node_name = "kp-nat4-in2out",
+  .runs_before = VNET_FEATURES ("ip4-lookup"),
+};
+
+VLIB_REGISTER_NODE (kp_nat4_in2out_node) =
+{
+  .function = kp_nat4_in2out_node_fn,
+  .name = "kp-nat4-in2out",
+  .vector_size = sizeof (u32),
+  .format_trace = format_kp_nat_trace,
+
+  .n_errors = KP_N_ERROR,
+  .error_strings = kp_error_strings,
+
+  .n_next_nodes = KP_NAT4_IN2OUT_N_NEXT,
+  .next_nodes =
+  {
+      [KP_NAT4_IN2OUT_NEXT_DROP] = "error-drop",
+      [KP_NAT4_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
+  },
+};