Punt: socket register for exception dispatched/punted packets based on reason

- add to the Punt API to allow different descriptions of the desired packets: UDP or exceptions
- move the punt nodes into punt_node.c
- improve tests (test that the correct packets are punted to the registered socket)

Change-Id: I1a133dec88106874993cba1f5a439cd26b2fef72
Signed-off-by: Neale Ranns <nranns@cisco.com>

20 files changed, 1561 insertions, 811 deletions

diff --git a/src/vat/api_format.c b/src/vat/api_format.c
index c57f045fdd4..fe8e6ecbb6e 100644
--- a/src/vat/api_format.c
+++ b/src/vat/api_format.c
@@ -20368,16 +20368,18 @@ static int
 api_set_punt (vat_main_t * vam)
 {
   unformat_input_t *i = vam->input;
+  vl_api_address_family_t af;
   vl_api_set_punt_t *mp;
   u32 ipv = ~0;
   u32 protocol = ~0;
   u32 port = ~0;
   int is_add = 1;
+  u8 is_ip4 = 1;
   int ret;
 
   while (unformat_check_input (i) != UNFORMAT_END_OF_INPUT)
     {
-      if (unformat (i, "ip %d", &ipv))
+      if (unformat (i, "%U", unformat_vl_api_address_family, &af))
 	;
       else if (unformat (i, "protocol %d", &protocol))
 	;
@@ -20395,9 +20397,10 @@ api_set_punt (vat_main_t * vam)
   M (SET_PUNT, mp);
 
   mp->is_add = (u8) is_add;
-  mp->punt.ipv = (u8) ipv;
-  mp->punt.l4_protocol = (u8) protocol;
-  mp->punt.l4_port = htons ((u16) port);
+  mp->punt.type = PUNT_API_TYPE_L4;
+  mp->punt.punt.l4.af = af;
+  mp->punt.punt.l4.protocol = (u8) protocol;
+  mp->punt.punt.l4.port = htons ((u16) port);
 
   S (mp);
   W (ret);
diff --git a/src/vlib/punt.c b/src/vlib/punt.c
index 5f83707c11d..7c2daf25ee4 100644
--- a/src/vlib/punt.c
+++ b/src/vlib/punt.c
@@ -367,6 +367,15 @@ vlib_punt_unregister (vlib_punt_hdl_t client,
 }
 
 int
+vlib_punt_reason_validate (vlib_punt_reason_t reason)
+{
+  if (reason < punt_reason_last)
+    return (0);
+
+  return (-1);
+}
+
+int
 vlib_punt_reason_alloc (vlib_punt_hdl_t client,
 			const char *reason_name, vlib_punt_reason_t * reason)
 {
@@ -392,6 +401,17 @@ vlib_punt_reason_alloc (vlib_punt_hdl_t client,
   return (0);
 }
 
+void
+punt_reason_walk (punt_reason_walk_cb_t cb, void *ctx)
+{
+  punt_reason_data_t *pd;
+
+  vec_foreach (pd, punt_reason_data)
+  {
+    cb (pd->pd_reason, pd->pd_name, ctx);
+  }
+}
+
 /* Parse node name -> node index. */
 uword
 unformat_punt_client (unformat_input_t * input, va_list * args)
diff --git a/src/vlib/punt.h b/src/vlib/punt.h
index adb25f91a5e..7a3e5da2da6 100644
--- a/src/vlib/punt.h
+++ b/src/vlib/punt.h
@@ -28,6 +28,13 @@ typedef enum vlib_punt_reason_t_
   PUNT_N_REASONS,
 } vlib_punt_reason_t;
 
+/**
+ * Walk each punt reason
+ */
+typedef int (*punt_reason_walk_cb_t) (vlib_punt_reason_t id,
+				      const u8 * name, void *ctx);
+
+extern void punt_reason_walk (punt_reason_walk_cb_t cb, void *cxt);
 
 /**
  * @brief Format a punt reason
@@ -57,6 +64,11 @@ extern int vlib_punt_reason_alloc (vlib_punt_hdl_t client,
 				   vlib_punt_reason_t * reason);
 
 /**
+ * Validate that a punt reason is assigned
+ */
+extern int vlib_punt_reason_validate (vlib_punt_reason_t reason);
+
+/**
  * @brief Register a node to receive particular punted buffers
  *
  * @paran client - The registered client registering for the packets
diff --git a/src/vnet/CMakeLists.txt b/src/vnet/CMakeLists.txt
index 1940abe03c2..dcbdb73d841 100644
--- a/src/vnet/CMakeLists.txt
+++ b/src/vnet/CMakeLists.txt
@@ -449,6 +449,7 @@ list(APPEND VNET_SOURCES
   ip/ping.c
   ip/punt_api.c
   ip/punt.c
+  ip/punt_node.c
 )
 
 list(APPEND VNET_MULTIARCH_SOURCES
@@ -459,7 +460,7 @@ list(APPEND VNET_MULTIARCH_SOURCES
   ip/ip6_reassembly.c
   ip/ip6_input.c
   ip/ip6_punt_drop.c
-  ip/punt.c
+  ip/punt_node.c
   ip/ip_in_out_acl.c
 )
 
diff --git a/src/vnet/ethernet/ethernet_types_api.c b/src/vnet/ethernet/ethernet_types_api.c
index 90b630d46be..145cf6ca40b 100644
--- a/src/vnet/ethernet/ethernet_types_api.c
+++ b/src/vnet/ethernet/ethernet_types_api.c
@@ -13,6 +13,7 @@
  * limitations under the License.
  */
 
+#include <vlibapi/api_types.h>
 #include <vnet/ethernet/ethernet_types_api.h>
 
 #define vl_typedefs		/* define message structures */
diff --git a/src/vnet/ip/ip.c b/src/vnet/ip/ip.c
index cab0cd0315a..6e8ac7c437d 100644
--- a/src/vnet/ip/ip.c
+++ b/src/vnet/ip/ip.c
@@ -278,6 +278,22 @@ ip6_mask_to_preflen (ip6_address_t * mask)
     return 64 - first0;
 }
 
+u8 *
+format_ip_address_family (u8 * s, va_list * args)
+{
+  ip_address_family_t af = va_arg (*args, ip_address_family_t);
+
+  switch (af)
+    {
+    case AF_IP4:
+      return (format (s, "ip4"));
+    case AF_IP6:
+      return (format (s, "ip6"));
+    }
+
+  return (format (s, "unknown"));
+}
+
 /*
  * fd.io coding-style-patch-verification: ON
  *
diff --git a/src/vnet/ip/ip.h b/src/vnet/ip/ip.h
index b114fcbaaf6..7a82dcf8f2b 100644
--- a/src/vnet/ip/ip.h
+++ b/src/vnet/ip/ip.h
@@ -65,6 +65,19 @@
 #include <vnet/ip/icmp6.h>
 #include <vnet/classify/vnet_classify.h>
 
+typedef enum ip_address_family_t_
+{
+  AF_IP4,
+  AF_IP6,
+} ip_address_family_t;
+
+extern uword unformat_ip_address_family (unformat_input_t * input,
+					 va_list * args);
+extern u8 *format_ip_address_family (u8 * s, va_list * args);
+
+#define FOR_EACH_IP_ADDRESS_FAMILY(_af) \
+  for (_af = AF_IP4; _af <= AF_IP6; _af++)
+
 #define u8_ptr_add(ptr, index) (((u8 *)ptr) + index)
 #define u16_net_add(u, val) clib_host_to_net_u16(clib_net_to_host_u16(u) + (val))
 
diff --git a/src/vnet/ip/ip_types.api b/src/vnet/ip/ip_types.api
index 29bd8ad37f5..a9e66470665 100644
--- a/src/vnet/ip/ip_types.api
+++ b/src/vnet/ip/ip_types.api
@@ -22,6 +22,11 @@ enum address_family {
   ADDRESS_IP6,
 };
 
+enum ip_proto {
+  IP_API_PROTO_TCP = 6,
+  IP_API_PROTO_UDP = 17,
+};
+
 union address_union {
   vl_api_ip4_address_t ip4;
   vl_api_ip6_address_t ip6;
diff --git a/src/vnet/ip/ip_types_api.c b/src/vnet/ip/ip_types_api.c
index b56101c355f..d84c1ff9126 100644
--- a/src/vnet/ip/ip_types_api.c
+++ b/src/vnet/ip/ip_types_api.c
@@ -13,6 +13,7 @@
  * limitations under the License.
  */
 
+#include <vlibapi/api_types.h>
 #include <vnet/ip/ip_types_api.h>
 
 #define vl_typedefs		/* define message structures */
@@ -29,6 +30,72 @@
 #include <vnet/vnet_all_api_h.h>
 #undef vl_printfun
 
+int
+ip_address_family_decode (int _af, ip_address_family_t * out)
+{
+  vl_api_address_family_t af = clib_host_to_net_u32 (_af);
+
+  switch (af)
+    {
+    case ADDRESS_IP4:
+      *out = AF_IP4;
+      return (0);
+    case ADDRESS_IP6:
+      *out = AF_IP6;
+      return (0);
+    }
+  return (-1);
+}
+
+int
+ip_address_family_encode (ip_address_family_t af)
+{
+  switch (af)
+    {
+    case AF_IP4:
+      return (clib_host_to_net_u32 (ADDRESS_IP4));
+    case AF_IP6:
+      return (clib_host_to_net_u32 (ADDRESS_IP6));
+    }
+
+  ASSERT (0);
+  return (clib_host_to_net_u32 (ADDRESS_IP4));
+}
+
+int
+ip_proto_decode (int _ipp, ip_protocol_t * out)
+{
+  vl_api_ip_proto_t ipp = clib_host_to_net_u32 (_ipp);
+
+  switch (ipp)
+    {
+    case IP_API_PROTO_TCP:
+      *out = IP_PROTOCOL_TCP;
+      return (0);
+    case IP_API_PROTO_UDP:
+      *out = IP_PROTOCOL_UDP;
+      return (0);
+    }
+  return (-1);
+}
+
+int
+ip_proto_encode (ip_protocol_t ipp)
+{
+  switch (ipp)
+    {
+    case IP_PROTOCOL_UDP:
+      return (clib_host_to_net_u32 (IP_API_PROTO_UDP));
+    case IP_PROTOCOL_TCP:
+      return (clib_host_to_net_u32 (IP_API_PROTO_TCP));
+    default:
+      break;
+    }
+
+  ASSERT (0);
+  return (clib_host_to_net_u32 (IP_API_PROTO_TCP));
+}
+
 void
 ip6_address_encode (const ip6_address_t * in, vl_api_ip6_address_t out)
 {
diff --git a/src/vnet/ip/ip_types_api.h b/src/vnet/ip/ip_types_api.h
index a67134c9a86..4c79bf138e3 100644
--- a/src/vnet/ip/ip_types_api.h
+++ b/src/vnet/ip/ip_types_api.h
@@ -33,6 +33,18 @@ struct _vl_api_address;
 struct _vl_api_prefix;
 struct _vl_api_mprefix;
 
+/**
+ * These enum decode/encodes use 'int' as the type for the enum becuase
+ * one cannot forward declare an enum
+ */
+extern int ip_address_family_decode (int _af, ip_address_family_t * out);
+extern int ip_address_family_encode (ip_address_family_t af);
+extern int ip_proto_decode (int _af, ip_protocol_t * out);
+extern int ip_proto_encode (ip_protocol_t af);
+
+/**
+ * Decode/Encode for struct/union types
+ */
 extern ip46_type_t ip_address_decode (const struct _vl_api_address *in,
 				      ip46_address_t * out);
 extern void ip_address_encode (const ip46_address_t * in,
diff --git a/src/vnet/ip/punt.api b/src/vnet/ip/punt.api
index c8b222a211b..cedddc5601d 100644
--- a/src/vnet/ip/punt.api
+++ b/src/vnet/ip/punt.api
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2016 Cisco and/or its affiliates.
+ * Copyright (c) 2015-2019 Cisco 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:
@@ -13,18 +13,55 @@
  * limitations under the License.
  */
 
-option version = "2.0.0";
+option version = "2.1.0";
+import "vnet/ip/ip_types.api";
 
-/** \brief Punt definition
-    @param ipv - L3 protocol 4 - IPv4, 6 - IPv6, ~0 - All
-    @param l4_protocol - L4 protocol to be punted
-    @param l4_port - TCP/UDP port to be punted
+/** \brief The types of packets to be punted
 */
-typeonly define punt
+enum punt_type
 {
-    u8 ipv;
-    u8 l4_protocol;
-    u16 l4_port;
+    /* L4 (UDP) packets */
+    PUNT_API_TYPE_L4,
+    /* Exception packets handled by the VLIB punt infra */
+    PUNT_API_TYPE_EXCEPTION,
+};
+
+/** \brief Punt L4 traffic definition
+    @param af - Address Family, IPv4 or IPV6
+    @param protocol - L4 protocol to be punted
+    @param port - TCP/UDP port to be punted
+*/
+typedef punt_l4
+{
+    vl_api_address_family_t af;
+    vl_api_ip_proto_t protocol;
+    u16 port;
+};
+
+/** \brief The ID of the punt exception reason
+           Dump all the reasons to obtain this
+*/
+typedef punt_exception
+{
+    u32 id;
+};
+
+/** \brief Union of the different punt packet descriptions
+*/
+union punt_union
+{
+    vl_api_punt_exception_t exception;
+    vl_api_punt_l4_t l4;
+};
+
+/** \brief Full description of which packets are requested to be punted
+    @param type - Which packet type
+    @param punt - Description corresponding to the type
+*/
+typedef punt
+{
+    vl_api_punt_type_t type;
+    vl_api_punt_union_t punt; 
 };
 
 /** \brief Punt traffic to the host
@@ -40,19 +77,6 @@ autoreply define set_punt {
     vl_api_punt_t punt;
 };
 
-define punt_dump
-{
-    u32 client_index;
-    u32 context;
-    u8 is_ipv6;
-};
-
-define punt_details
-{
-    u32 context;
-    vl_api_punt_t punt;
-};
-
 /** \brief Punt traffic to the host via socket
     @param client_index - opaque cookie to identify the sender
     @param context - sender context, to match reply w/ request
@@ -78,7 +102,7 @@ define punt_socket_dump
 {
     u32 client_index;
     u32 context;
-    u8 is_ipv6;
+    vl_api_punt_type_t type;
 };
 
 define punt_socket_details
@@ -94,6 +118,26 @@ autoreply define punt_socket_deregister {
     vl_api_punt_t punt;
 };
 
+/** \brief Dump all of the excpetion punt reasons
+*/
+define punt_reason_dump
+{
+    u32 client_index;
+    u32 context;
+};
+
+typedef punt_reason
+{
+    u32 id;
+    string name;
+};
+
+define punt_reason_details
+{
+    u32 context;
+    vl_api_punt_reason_t reason;
+};
+
 /*
  * Local Variables:
  * eval: (c-set-style "gnu")
diff --git a/src/vnet/ip/punt.c b/src/vnet/ip/punt.c
index 743df1fef0b..d4d502887d7 100644
--- a/src/vnet/ip/punt.c
+++ b/src/vnet/ip/punt.c
@@ -29,7 +29,6 @@
 #include <vnet/tcp/tcp.h>
 #include <vnet/sctp/sctp.h>
 #include <vnet/ip/punt.h>
-#include <vppinfra/sparse_vec.h>
 #include <vlib/unix/unix.h>
 
 #include <stdio.h>
@@ -38,37 +37,6 @@
 #include <sys/uio.h>
 #include <stdlib.h>
 
-#define foreach_punt_next			\
-  _ (PUNT4, "ip4-punt")                         \
-  _ (PUNT6, "ip6-punt")
-
-typedef enum
-{
-#define _(s,n) PUNT_NEXT_##s,
-  foreach_punt_next
-#undef _
-    PUNT_N_NEXT,
-} punt_next_t;
-
-enum punt_socket_rx_next_e
-{
-  PUNT_SOCKET_RX_NEXT_INTERFACE_OUTPUT,
-  PUNT_SOCKET_RX_NEXT_IP4_LOOKUP,
-  PUNT_SOCKET_RX_NEXT_IP6_LOOKUP,
-  PUNT_SOCKET_RX_N_NEXT
-};
-
-#define punt_next_punt(is_ip4) (is_ip4 ? PUNT_NEXT_PUNT4 : PUNT_NEXT_PUNT6)
-
-extern vlib_node_registration_t udp4_punt_node;
-extern vlib_node_registration_t udp6_punt_node;
-extern vlib_node_registration_t udp4_punt_socket_node;
-extern vlib_node_registration_t udp6_punt_socket_node;
-static vlib_node_registration_t punt_socket_rx_node;
-
-extern punt_main_t punt_main;
-
-#ifndef CLIB_MARCH_VARIANT
 punt_main_t punt_main;
 
 char *
@@ -77,571 +45,179 @@ vnet_punt_get_server_pathname (void)
   punt_main_t *pm = &punt_main;
   return pm->sun_path;
 }
-#endif /* CLIB_MARCH_VARIANT */
-
-/** @brief IPv4/IPv6 UDP punt node main loop.
-
-    This is the main loop inline function for IPv4/IPv6 UDP punt
-    transition node.
-
-    @param vm vlib_main_t corresponding to the current thread
-    @param node vlib_node_runtime_t
-    @param frame vlib_frame_t whose contents should be dispatched
-    @param is_ipv4 indicates if called for IPv4 or IPv6 node
-*/
-always_inline uword
-udp46_punt_inline (vlib_main_t * vm,
-		   vlib_node_runtime_t * node,
-		   vlib_frame_t * from_frame, int is_ip4)
-{
-  u32 n_left_from, *from, *to_next;
-  word advance;
-
-  from = vlib_frame_vector_args (from_frame);
-  n_left_from = from_frame->n_vectors;
-
-  /* udp[46]_lookup hands us the data payload, not the IP header */
-  if (is_ip4)
-    advance = -(sizeof (ip4_header_t) + sizeof (udp_header_t));
-  else
-    advance = -(sizeof (ip6_header_t) + sizeof (udp_header_t));
-
-  while (n_left_from > 0)
-    {
-      u32 n_left_to_next;
-
-      vlib_get_next_frame (vm, node, punt_next_punt (is_ip4), to_next,
-			   n_left_to_next);
 
-      while (n_left_from > 0 && n_left_to_next > 0)
-	{
-	  u32 bi0;
-	  vlib_buffer_t *b0;
-
-	  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);
-	  vlib_buffer_advance (b0, advance);
-	  b0->error = node->errors[PUNT_ERROR_UDP_PORT];
-	}
-
-      vlib_put_next_frame (vm, node, punt_next_punt (is_ip4), n_left_to_next);
-    }
-
-  return from_frame->n_vectors;
-}
-
-static char *punt_error_strings[] = {
-#define punt_error(n,s) s,
-#include "punt_error.def"
-#undef punt_error
-};
-
-/** @brief IPv4 UDP punt node.
-    @node ip4-udp-punt
-
-    This is the IPv4 UDP punt transition node. It is registered as a next
-    node for the "ip4-udp-lookup" handling UDP port(s) requested for punt.
-    The buffer's current data pointer is adjusted to the original packet
-    IPv4 header. All buffers are dispatched to "error-punt".
-
-    @param vm vlib_main_t corresponding to the current thread
-    @param node vlib_node_runtime_t
-    @param frame vlib_frame_t whose contents should be dispatched
-
-    @par Graph mechanics: next index usage
-
-    @em Sets:
-    - <code>vnet_buffer(b)->current_data</code>
-    - <code>vnet_buffer(b)->current_len</code>
-
-    <em>Next Index:</em>
-    - Dispatches the packet to the "error-punt" node
-*/
-VLIB_NODE_FN (udp4_punt_node) (vlib_main_t * vm,
-			       vlib_node_runtime_t * node,
-			       vlib_frame_t * from_frame)
+static void
+punt_client_l4_db_add (ip_address_family_t af, u16 port, u32 index)
 {
-  return udp46_punt_inline (vm, node, from_frame, 1 /* is_ip4 */ );
-}
-
-/** @brief IPv6 UDP punt node.
-    @node ip6-udp-punt
-
-    This is the IPv6 UDP punt transition node. It is registered as a next
-    node for the "ip6-udp-lookup" handling UDP port(s) requested for punt.
-    The buffer's current data pointer is adjusted to the original packet
-    IPv6 header. All buffers are dispatched to "error-punt".
-
-    @param vm vlib_main_t corresponding to the current thread
-    @param node vlib_node_runtime_t
-    @param frame vlib_frame_t whose contents should be dispatched
-
-    @par Graph mechanics: next index usage
-
-    @em Sets:
-    - <code>vnet_buffer(b)->current_data</code>
-    - <code>vnet_buffer(b)->current_len</code>
+  punt_main_t *pm = &punt_main;
 
-    <em>Next Index:</em>
-    - Dispatches the packet to the "error-punt" node
-*/
-VLIB_NODE_FN (udp6_punt_node) (vlib_main_t * vm,
-			       vlib_node_runtime_t * node,
-			       vlib_frame_t * from_frame)
-{
-  return udp46_punt_inline (vm, node, from_frame, 0 /* is_ip4 */ );
+  pm->db.clients_by_l4_port = hash_set (pm->db.clients_by_l4_port,
+					punt_client_l4_mk_key (af, port),
+					index);
 }
 
-/* *INDENT-OFF* */
-VLIB_REGISTER_NODE (udp4_punt_node) = {
-  .name = "ip4-udp-punt",
-  /* Takes a vector of packets. */
-  .vector_size = sizeof (u32),
-
-  .n_errors = PUNT_N_ERROR,
-  .error_strings = punt_error_strings,
-
-  .n_next_nodes = PUNT_N_NEXT,
-  .next_nodes = {
-#define _(s,n) [PUNT_NEXT_##s] = n,
-     foreach_punt_next
-#undef _
-  },
-};
-
-VLIB_REGISTER_NODE (udp6_punt_node) = {
-  .name = "ip6-udp-punt",
-  /* Takes a vector of packets. */
-  .vector_size = sizeof (u32),
-
-  .n_errors = PUNT_N_ERROR,
-  .error_strings = punt_error_strings,
-
-  .n_next_nodes = PUNT_N_NEXT,
-  .next_nodes = {
-#define _(s,n) [PUNT_NEXT_##s] = n,
-     foreach_punt_next
-#undef _
-  },
-};
-
-/* *INDENT-ON* */
-
-static punt_client_t *
-punt_client_get (bool is_ip4, u16 port)
+static u32
+punt_client_l4_db_remove (ip_address_family_t af, u16 port)
 {
   punt_main_t *pm = &punt_main;
-  punt_client_t *v =
-    is_ip4 ? pm->clients_by_dst_port4 : pm->clients_by_dst_port6;
+  u32 key, index = ~0;
+  uword *p;
 
-  u16 i = sparse_vec_index (v, port);
-  if (i == SPARSE_VEC_INVALID_INDEX)
-    return 0;
+  key = punt_client_l4_mk_key (af, port);
+  p = hash_get (pm->db.clients_by_l4_port, key);
 
-  return &vec_elt (v, i);
-}
+  if (p)
+    index = p[0];
 
-static struct sockaddr_un *
-punt_socket_get (bool is_ip4, u16 port)
-{
-  punt_client_t *v = punt_client_get (is_ip4, port);
-  if (v)
-    return &v->caddr;
+  hash_unset (pm->db.clients_by_l4_port, key);
 
-  return NULL;
+  return (index);
 }
 
-#ifndef CLIB_MARCH_VARIANT
-static int
-punt_socket_register (bool is_ip4, u8 protocol, u16 port,
-		      char *client_pathname)
+static void
+punt_client_exception_db_add (vlib_punt_reason_t reason, u32 pci)
 {
   punt_main_t *pm = &punt_main;
-  punt_client_t c, *n;
-  punt_client_t *v = is_ip4 ? pm->clients_by_dst_port4 :
-    pm->clients_by_dst_port6;
 
-  if (strncmp (client_pathname, vnet_punt_get_server_pathname (),
-	       UNIX_PATH_MAX) == 0)
-    return -1;
-
-  clib_memset (&c, 0, sizeof (c));
-  memcpy (c.caddr.sun_path, client_pathname, sizeof (c.caddr.sun_path));
-  c.caddr.sun_family = AF_UNIX;
-  c.port = port;
-  c.protocol = protocol;
-  n = sparse_vec_validate (v, port);
-  n[0] = c;
-  return 0;
-}
+  vec_validate_init_empty (pm->db.clients_by_exception, reason, ~0);
 
-/* $$$$ Just leaves the mapping in place for now */
-static void
-punt_socket_unregister (bool is_ip4, u8 protocol, u16 port)
-{
-  return;
+  pm->db.clients_by_exception[reason] = pci;
 }
-#endif /* CLIB_MARCH_VARIANT */
 
-typedef struct
+static u32
+punt_client_exception_db_remove (vlib_punt_reason_t reason)
 {
-  punt_client_t client;
-  u8 is_midchain;
-} udp_punt_trace_t;
+  punt_main_t *pm = &punt_main;
+  u32 pci = ~0;
 
-static u8 *
-format_udp_punt_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 *);
-  udp_punt_trace_t *t = va_arg (*args, udp_punt_trace_t *);
-  u32 indent = format_get_indent (s);
-  s = format (s, "to: %s", t->client.caddr.sun_path);
-  if (t->is_midchain)
+  if (punt_client_exception_get (reason))
     {
-      s = format (s, "\n%U(buffer is part of chain)", format_white_space,
-		  indent);
+      pci = pm->db.clients_by_exception[reason];
+      pm->db.clients_by_exception[reason] = ~0;
     }
-  return s;
+
+  return pci;
 }
 
-always_inline uword
-udp46_punt_socket_inline (vlib_main_t * vm,
-			  vlib_node_runtime_t * node,
-			  vlib_frame_t * frame, bool is_ip4)
+static clib_error_t *
+punt_socket_read_ready (clib_file_t * uf)
 {
-  u32 *buffers = vlib_frame_vector_args (frame);
-  uword n_packets = frame->n_vectors;
-  struct iovec *iovecs = 0;
+  vlib_main_t *vm = vlib_get_main ();
   punt_main_t *pm = &punt_main;
-  int i;
-
-  u32 node_index = is_ip4 ? udp4_punt_socket_node.index :
-    udp6_punt_socket_node.index;
-
-  for (i = 0; i < n_packets; i++)
-    {
-      struct iovec *iov;
-      vlib_buffer_t *b;
-      uword l;
-      punt_packetdesc_t packetdesc;
-
-      b = vlib_get_buffer (vm, buffers[i]);
-
-      /* Reverse UDP Punt advance */
-      udp_header_t *udp;
-      if (is_ip4)
-	{
-	  vlib_buffer_advance (b, -(sizeof (ip4_header_t) +
-				    sizeof (udp_header_t)));
-	  ip4_header_t *ip = vlib_buffer_get_current (b);
-	  udp = (udp_header_t *) (ip + 1);
-	}
-      else
-	{
-	  vlib_buffer_advance (b, -(sizeof (ip6_header_t) +
-				    sizeof (udp_header_t)));
-	  ip6_header_t *ip = vlib_buffer_get_current (b);
-	  udp = (udp_header_t *) (ip + 1);
-	}
-
-      u16 port = clib_net_to_host_u16 (udp->dst_port);
-
-      /*
-       * Find registerered client
-       * If no registered client, drop packet and count
-       */
-      struct sockaddr_un *caddr;
-      caddr = punt_socket_get (is_ip4, port);
-      if (!caddr)
-	{
-	  vlib_node_increment_counter (vm, node_index,
-				       PUNT_ERROR_SOCKET_TX_ERROR, 1);
-	  goto error;
-	}
-
-      punt_client_t *c = NULL;
-      if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
-	{
-	  c = punt_client_get (is_ip4, port);
-	  udp_punt_trace_t *t;
-	  t = vlib_add_trace (vm, node, b, sizeof (t[0]));
-	  clib_memcpy_fast (&t->client, c, sizeof (t->client));
-	}
-
-      /* Re-set iovecs if present. */
-      if (iovecs)
-	_vec_len (iovecs) = 0;
-
-      /* Add packet descriptor */
-      packetdesc.sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
-      packetdesc.action = 0;
-      vec_add2 (iovecs, iov, 1);
-      iov->iov_base = &packetdesc;
-      iov->iov_len = sizeof (packetdesc);
-
-      /** VLIB buffer chain -> Unix iovec(s). */
-      vlib_buffer_advance (b, -(sizeof (ethernet_header_t)));
-      vec_add2 (iovecs, iov, 1);
-      iov->iov_base = b->data + b->current_data;
-      iov->iov_len = l = b->current_length;
-
-      if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
-	{
-	  do
-	    {
-	      b = vlib_get_buffer (vm, b->next_buffer);
-	      if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
-		{
-		  if (PREDICT_FALSE (!c))
-		    {
-		      c = punt_client_get (is_ip4, port);
-		    }
-		  udp_punt_trace_t *t;
-		  t = vlib_add_trace (vm, node, b, sizeof (t[0]));
-		  clib_memcpy_fast (&t->client, c, sizeof (t->client));
-		  t->is_midchain = 1;
-		}
-
-	      vec_add2 (iovecs, iov, 1);
-
-	      iov->iov_base = b->data + b->current_data;
-	      iov->iov_len = b->current_length;
-	      l += b->current_length;
-	    }
-	  while (b->flags & VLIB_BUFFER_NEXT_PRESENT);
-	}
-
-      struct msghdr msg = {
-	.msg_name = caddr,
-	.msg_namelen = sizeof (*caddr),
-	.msg_iov = iovecs,
-	.msg_iovlen = vec_len (iovecs),
-      };
-
-      if (sendmsg (pm->socket_fd, &msg, 0) < (ssize_t) l)
-	vlib_node_increment_counter (vm, node_index,
-				     PUNT_ERROR_SOCKET_TX_ERROR, 1);
-      else
-	vlib_node_increment_counter (vm, node_index, PUNT_ERROR_SOCKET_TX, 1);
 
-    }
-
-error:
-  vlib_buffer_free (vm, buffers, n_packets);
-
-  return n_packets;
-}
+  /** Schedule the rx node */
+  vlib_node_set_interrupt_pending (vm, punt_socket_rx_node.index);
+  vec_add1 (pm->ready_fds, uf->file_descriptor);
 
-static uword
-udp4_punt_socket (vlib_main_t * vm,
-		  vlib_node_runtime_t * node, vlib_frame_t * from_frame)
-{
-  return udp46_punt_socket_inline (vm, node, from_frame, true /* is_ip4 */ );
+  return 0;
 }
 
-static uword
-udp6_punt_socket (vlib_main_t * vm,
-		  vlib_node_runtime_t * node, vlib_frame_t * from_frame)
+static clib_error_t *
+punt_socket_register_l4 (vlib_main_t * vm,
+			 ip_address_family_t af,
+			 u8 protocol, u16 port, char *client_pathname)
 {
-  return udp46_punt_socket_inline (vm, node, from_frame, false /* is_ip4 */ );
-}
-
-
-/* *INDENT-OFF* */
-VLIB_REGISTER_NODE (udp4_punt_socket_node) = {
-  .function = udp4_punt_socket,
-  .name = "ip4-udp-punt-socket",
-  .format_trace = format_udp_punt_trace,
-  .flags = VLIB_NODE_FLAG_IS_DROP,
-  /* Takes a vector of packets. */
-  .vector_size = sizeof (u32),
-  .n_errors = PUNT_N_ERROR,
-  .error_strings = punt_error_strings,
-};
-VLIB_REGISTER_NODE (udp6_punt_socket_node) = {
-  .function = udp6_punt_socket,
-  .name = "ip6-udp-punt-socket",
-  .format_trace = format_udp_punt_trace,
-  .flags = VLIB_NODE_FLAG_IS_DROP,
-  .vector_size = sizeof (u32),
-  .n_errors = PUNT_N_ERROR,
-  .error_strings = punt_error_strings,
-};
-/* *INDENT-ON* */
+  punt_main_t *pm = &punt_main;
+  punt_client_t *c;
 
-typedef struct
-{
-  enum punt_action_e action;
-  u32 sw_if_index;
-} punt_trace_t;
+  /* For now we only support UDP punt */
+  if (protocol != IP_PROTOCOL_UDP)
+    return clib_error_return (0,
+			      "only UDP protocol (%d) is supported, got %d",
+			      IP_PROTOCOL_UDP, protocol);
 
-static u8 *
-format_punt_trace (u8 * s, va_list * va)
-{
-  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
-  CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *);
-  vnet_main_t *vnm = vnet_get_main ();
-  punt_trace_t *t = va_arg (*va, punt_trace_t *);
-  s = format (s, "%U Action: %d", format_vnet_sw_if_index_name,
-	      vnm, t->sw_if_index, t->action);
-  return s;
-}
+  if (port == (u16) ~ 0)
+    return clib_error_return (0, "UDP port number required");
 
-static uword
-punt_socket_rx_fd (vlib_main_t * vm, vlib_node_runtime_t * node, u32 fd)
-{
-  const uword buffer_size = vlib_buffer_get_default_data_size (vm);
-  u32 n_trace = vlib_get_trace_count (vm, node);
-  u32 next = node->cached_next_index;
-  u32 n_left_to_next, next_index;
-  u32 *to_next;
-  u32 error = PUNT_ERROR_NONE;
-  vlib_get_next_frame (vm, node, next, to_next, n_left_to_next);
-
-  /* $$$$ Only dealing with one buffer at the time for now */
-
-  u32 bi;
-  vlib_buffer_t *b;
-  punt_packetdesc_t packetdesc;
-  ssize_t size;
-  struct iovec io[2];
-
-  if (vlib_buffer_alloc (vm, &bi, 1) != 1)
-    {
-      error = PUNT_ERROR_NOBUFFER;
-      goto error;
-    }
+  if (strncmp (client_pathname, vnet_punt_get_server_pathname (),
+	       UNIX_PATH_MAX) == 0)
+    return clib_error_return (0,
+			      "Punt socket: Invalid client path: %s",
+			      client_pathname);
 
-  b = vlib_get_buffer (vm, bi);
-  io[0].iov_base = &packetdesc;
-  io[0].iov_len = sizeof (packetdesc);
-  io[1].iov_base = b->data;
-  io[1].iov_len = buffer_size;
+  c = punt_client_l4_get (af, port);
 
-  size = readv (fd, io, 2);
-  /* We need at least the packet descriptor plus a header */
-  if (size <= (int) (sizeof (packetdesc) + sizeof (ip4_header_t)))
+  if (NULL == c)
     {
-      vlib_buffer_free (vm, &bi, 1);
-      error = PUNT_ERROR_READV;
-      goto error;
+      pool_get_zero (pm->punt_client_pool, c);
+      punt_client_l4_db_add (af, port, c - pm->punt_client_pool);
     }
 
-  b->flags = VNET_BUFFER_F_LOCALLY_ORIGINATED;
-  b->current_length = size - sizeof (packetdesc);
+  memcpy (c->caddr.sun_path, client_pathname, sizeof (c->caddr.sun_path));
+  c->caddr.sun_family = AF_UNIX;
+  c->reg.type = PUNT_TYPE_L4;
+  c->reg.punt.l4.port = port;
+  c->reg.punt.l4.protocol = protocol;
+  c->reg.punt.l4.af = af;
 
-  VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b);
+  u32 node_index = (af == AF_IP4 ?
+		    udp4_punt_socket_node.index :
+		    udp6_punt_socket_node.index);
 
-  switch (packetdesc.action)
-    {
-    case PUNT_L2:
-      vnet_buffer (b)->sw_if_index[VLIB_TX] = packetdesc.sw_if_index;
-      next_index = PUNT_SOCKET_RX_NEXT_INTERFACE_OUTPUT;
-      break;
+  udp_register_dst_port (vm, port, node_index, af == AF_IP4);
 
-    case PUNT_IP4_ROUTED:
-      vnet_buffer (b)->sw_if_index[VLIB_RX] = packetdesc.sw_if_index;
-      vnet_buffer (b)->sw_if_index[VLIB_TX] = ~0;
-      next_index = PUNT_SOCKET_RX_NEXT_IP4_LOOKUP;
-      break;
+  return (NULL);
+}
 
-    case PUNT_IP6_ROUTED:
-      vnet_buffer (b)->sw_if_index[VLIB_RX] = packetdesc.sw_if_index;
-      vnet_buffer (b)->sw_if_index[VLIB_TX] = ~0;
-      next_index = PUNT_SOCKET_RX_NEXT_IP6_LOOKUP;
-      break;
+static clib_error_t *
+punt_socket_register_exception (vlib_main_t * vm,
+				vlib_punt_reason_t reason,
+				char *client_pathname)
+{
+  punt_main_t *pm = &punt_main;
+  punt_client_t *pc;
 
-    default:
-      error = PUNT_ERROR_ACTION;
-      vlib_buffer_free (vm, &bi, 1);
-      goto error;
-    }
+  pc = punt_client_exception_get (reason);
 
-  if (PREDICT_FALSE (n_trace > 0))
+  if (NULL == pc)
     {
-      punt_trace_t *t;
-      vlib_trace_buffer (vm, node, next_index, b, 1 /* follow_chain */ );
-      vlib_set_trace_count (vm, node, --n_trace);
-      t = vlib_add_trace (vm, node, b, sizeof (*t));
-      t->sw_if_index = packetdesc.sw_if_index;
-      t->action = packetdesc.action;
+      pool_get_zero (pm->punt_client_pool, pc);
+      punt_client_exception_db_add (reason, pc - pm->punt_client_pool);
     }
 
-  to_next[0] = bi;
-  to_next++;
-  n_left_to_next--;
+  memcpy (pc->caddr.sun_path, client_pathname, sizeof (pc->caddr.sun_path));
+  pc->caddr.sun_family = AF_UNIX;
+  pc->reg.type = PUNT_TYPE_EXCEPTION;
+  pc->reg.punt.exception.reason = reason;
 
-  vlib_validate_buffer_enqueue_x1 (vm, node, next, to_next, n_left_to_next,
-				   bi, next_index);
-  vlib_put_next_frame (vm, node, next, n_left_to_next);
-  return 1;
+  vlib_punt_register (pm->hdl,
+		      pc->reg.punt.exception.reason, "exception-punt-socket");
 
-error:
-  vlib_node_increment_counter (vm, punt_socket_rx_node.index, error, 1);
-  return 0;
+  return (NULL);
 }
 
-static uword
-punt_socket_rx (vlib_main_t * vm,
-		vlib_node_runtime_t * node, vlib_frame_t * frame)
+static clib_error_t *
+punt_socket_unregister_l4 (ip_address_family_t af,
+			   ip_protocol_t protocol, u16 port)
 {
-  punt_main_t *pm = &punt_main;
-  u32 total_count = 0;
-  int i;
+  u32 pci;
 
-  for (i = 0; i < vec_len (pm->ready_fds); i++)
-    {
-      total_count += punt_socket_rx_fd (vm, node, pm->ready_fds[i]);
-      vec_del1 (pm->ready_fds, i);
-    }
-  return total_count;
-}
+  udp_unregister_dst_port (vlib_get_main (), port, af == AF_IP4);
 
-/* *INDENT-OFF* */
-VLIB_REGISTER_NODE (punt_socket_rx_node, static) =
-{
- .function = punt_socket_rx,
- .name = "punt-socket-rx",
- .type = VLIB_NODE_TYPE_INPUT,
- .state = VLIB_NODE_STATE_INTERRUPT,
- .vector_size = 1,
- .n_errors = PUNT_N_ERROR,
- .error_strings = punt_error_strings,
- .n_next_nodes = PUNT_SOCKET_RX_N_NEXT,
- .next_nodes = {
-		[PUNT_SOCKET_RX_NEXT_INTERFACE_OUTPUT] = "interface-output",
-		[PUNT_SOCKET_RX_NEXT_IP4_LOOKUP] = "ip4-lookup",
-		[PUNT_SOCKET_RX_NEXT_IP6_LOOKUP] = "ip6-lookup",
-		},
- .format_trace = format_punt_trace,
-};
-/* *INDENT-ON* */
+  pci = punt_client_l4_db_remove (af, port);
+
+  if (~0 != pci)
+    pool_put_index (punt_main.punt_client_pool, pci);
+
+  return (NULL);
+}
 
 static clib_error_t *
-punt_socket_read_ready (clib_file_t * uf)
+punt_socket_unregister_exception (vlib_punt_reason_t reason)
 {
-  vlib_main_t *vm = vlib_get_main ();
-  punt_main_t *pm = &punt_main;
+  u32 pci;
 
-  /** Schedule the rx node */
-  vlib_node_set_interrupt_pending (vm, punt_socket_rx_node.index);
-  vec_add1 (pm->ready_fds, uf->file_descriptor);
+  pci = punt_client_exception_db_remove (reason);
 
-  return 0;
+  if (~0 != pci)
+    pool_put_index (punt_main.punt_client_pool, pci);
+
+  return (NULL);
 }
 
-#ifndef CLIB_MARCH_VARIANT
 clib_error_t *
 vnet_punt_socket_add (vlib_main_t * vm, u32 header_version,
-		      bool is_ip4, u8 protocol, u16 port,
-		      char *client_pathname)
+		      const punt_reg_t * pr, char *client_pathname)
 {
   punt_main_t *pm = &punt_main;
 
@@ -651,39 +227,40 @@ vnet_punt_socket_add (vlib_main_t * vm, u32 header_version,
   if (header_version != PUNT_PACKETDESC_VERSION)
     return clib_error_return (0, "Invalid packet descriptor version");
 
-  /* For now we only support UDP punt */
-  if (protocol != IP_PROTOCOL_UDP)
-    return clib_error_return (0,
-			      "only UDP protocol (%d) is supported, got %d",
-			      IP_PROTOCOL_UDP, protocol);
-
-  if (port == (u16) ~ 0)
-    return clib_error_return (0, "UDP port number required");
-
   /* Register client */
-  if (punt_socket_register (is_ip4, protocol, port, client_pathname) < 0)
-    return clib_error_return (0,
-			      "Punt socket: Invalid client path: %s",
-			      client_pathname);
-
-  u32 node_index = is_ip4 ? udp4_punt_socket_node.index :
-    udp6_punt_socket_node.index;
-
-  udp_register_dst_port (vm, port, node_index, is_ip4);
+  switch (pr->type)
+    {
+    case PUNT_TYPE_L4:
+      return (punt_socket_register_l4 (vm,
+				       pr->punt.l4.af,
+				       pr->punt.l4.protocol,
+				       pr->punt.l4.port, client_pathname));
+    case PUNT_TYPE_EXCEPTION:
+      return (punt_socket_register_exception (vm,
+					      pr->punt.exception.reason,
+					      client_pathname));
+    }
 
   return 0;
 }
 
 clib_error_t *
-vnet_punt_socket_del (vlib_main_t * vm, bool is_ip4, u8 l4_protocol, u16 port)
+vnet_punt_socket_del (vlib_main_t * vm, const punt_reg_t * pr)
 {
   punt_main_t *pm = &punt_main;
 
   if (!pm->is_configured)
     return clib_error_return (0, "socket is not configured");
 
-  punt_socket_unregister (is_ip4, l4_protocol, port);
-  udp_unregister_dst_port (vm, port, is_ip4);
+  switch (pr->type)
+    {
+    case PUNT_TYPE_L4:
+      return (punt_socket_unregister_l4 (pr->punt.l4.af,
+					 pr->punt.l4.protocol,
+					 pr->punt.l4.port));
+    case PUNT_TYPE_EXCEPTION:
+      return (punt_socket_unregister_exception (pr->punt.exception.reason));
+    }
 
   return 0;
 }
@@ -692,11 +269,10 @@ vnet_punt_socket_del (vlib_main_t * vm, bool is_ip4, u8 l4_protocol, u16 port)
  * @brief Request IP traffic punt to the local TCP/IP stack.
  *
  * @em Note
- * - UDP and TCP are the only protocols supported in the current implementation
+ * - UDP, TCP and SCTP are the only protocols supported in the current implementation
  *
  * @param vm       vlib_main_t corresponding to the current thread
- * @param ipv      IP protcol version.
- *                 4 - IPv4, 6 - IPv6, ~0 for both IPv6 and IPv4
+ * @param af       IP address family.
  * @param protocol 8-bits L4 protocol value
  *                 UDP is 17
  *                 TCP is 1
@@ -704,11 +280,11 @@ vnet_punt_socket_del (vlib_main_t * vm, bool is_ip4, u8 l4_protocol, u16 port)
  *
  * @returns 0 on success, non-zero value otherwise
  */
-clib_error_t *
-vnet_punt_add_del (vlib_main_t * vm, u8 ipv, u8 protocol, u16 port,
-		   bool is_add)
+static clib_error_t *
+punt_l4_add_del (vlib_main_t * vm,
+		 ip_address_family_t af,
+		 ip_protocol_t protocol, u16 port, bool is_add)
 {
-
   /* For now we only support TCP, UDP and SCTP punt */
   if (protocol != IP_PROTOCOL_UDP &&
       protocol != IP_PROTOCOL_TCP && protocol != IP_PROTOCOL_SCTP)
@@ -717,30 +293,14 @@ vnet_punt_add_del (vlib_main_t * vm, u8 ipv, u8 protocol, u16 port,
 			      IP_PROTOCOL_UDP, IP_PROTOCOL_TCP,
 			      IP_PROTOCOL_SCTP, protocol);
 
-  if (ipv != (u8) ~ 0 && ipv != 4 && ipv != 6)
-    return clib_error_return (0, "IP version must be 4 or 6, got %d", ipv);
-
   if (port == (u16) ~ 0)
     {
-      if ((ipv == 4) || (ipv == (u8) ~ 0))
-	{
-	  if (protocol == IP_PROTOCOL_UDP)
-	    udp_punt_unknown (vm, 1, is_add);
-	  else if (protocol == IP_PROTOCOL_TCP)
-	    tcp_punt_unknown (vm, 1, is_add);
-	  else if (protocol == IP_PROTOCOL_SCTP)
-	    sctp_punt_unknown (vm, 1, is_add);
-	}
-
-      if ((ipv == 6) || (ipv == (u8) ~ 0))
-	{
-	  if (protocol == IP_PROTOCOL_UDP)
-	    udp_punt_unknown (vm, 0, is_add);
-	  else if (protocol == IP_PROTOCOL_TCP)
-	    tcp_punt_unknown (vm, 0, is_add);
-	  else if (protocol == IP_PROTOCOL_SCTP)
-	    sctp_punt_unknown (vm, 0, is_add);
-	}
+      if (protocol == IP_PROTOCOL_UDP)
+	udp_punt_unknown (vm, af == AF_IP4, is_add);
+      else if (protocol == IP_PROTOCOL_TCP)
+	tcp_punt_unknown (vm, af == AF_IP4, is_add);
+      else if (protocol == IP_PROTOCOL_SCTP)
+	sctp_punt_unknown (vm, af == AF_IP4, is_add);
 
       return 0;
     }
@@ -751,11 +311,10 @@ vnet_punt_add_del (vlib_main_t * vm, u8 ipv, u8 protocol, u16 port,
 	return clib_error_return (0,
 				  "punt TCP/SCTP ports is not supported yet");
 
-      if (ipv == 4 || ipv == (u8) ~ 0)
-	udp_register_dst_port (vm, port, udp4_punt_node.index, 1);
+      if (!udp_is_valid_dst_port (port, af == AF_IP4))
+	return clib_error_return (0, "invalid port: %d", port);
 
-      if (ipv == 6 || ipv == (u8) ~ 0)
-	udp_register_dst_port (vm, port, udp6_punt_node.index, 0);
+      udp_register_dst_port (vm, port, udp4_punt_node.index, af == AF_IP4);
 
       return 0;
     }
@@ -764,38 +323,66 @@ vnet_punt_add_del (vlib_main_t * vm, u8 ipv, u8 protocol, u16 port,
       if (protocol == IP_PROTOCOL_TCP || protocol == IP_PROTOCOL_SCTP)
 	return clib_error_return (0,
 				  "punt TCP/SCTP ports is not supported yet");
-      if (ipv == 4 || ipv == (u8) ~ 0)
-	udp_unregister_dst_port (vm, port, 1);
 
-      if (ipv == 6 || ipv == (u8) ~ 0)
-	udp_unregister_dst_port (vm, port, 0);
+      udp_unregister_dst_port (vm, port, af == AF_IP4);
 
       return 0;
     }
 }
-#endif /* CLIB_MARCH_VARIANT */
+
+static clib_error_t *
+punt_exception_add_del (vlib_main_t * vm,
+			vlib_punt_reason_t reason, bool is_add)
+{
+  return (NULL);
+}
+
+clib_error_t *
+vnet_punt_add_del (vlib_main_t * vm, const punt_reg_t * pr, bool is_add)
+{
+  switch (pr->type)
+    {
+    case PUNT_TYPE_L4:
+      return (punt_l4_add_del (vm, pr->punt.l4.af, pr->punt.l4.protocol,
+			       pr->punt.l4.port, is_add));
+    case PUNT_TYPE_EXCEPTION:
+      return (punt_exception_add_del (vm, pr->punt.exception.reason, is_add));
+    }
+
+  return (clib_error_return (0, "Unsupported punt type: %d", pr->type));
+}
 
 static clib_error_t *
 punt_cli (vlib_main_t * vm,
 	  unformat_input_t * input, vlib_cli_command_t * cmd)
 {
-  u32 port = ~0;
-  bool is_add = true;
-  u32 protocol = ~0;
   clib_error_t *error = NULL;
+  bool is_add = true;
+  punt_reg_t pr = {
+    .punt = {
+	     .l4 = {
+		    .af = AF_IP4,
+		    .port = ~0,
+		    .protocol = ~0,
+		    },
+	     },
+    .type = PUNT_TYPE_L4,
+  };
 
   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
     {
       if (unformat (input, "del"))
 	is_add = false;
-      else if (unformat (input, "all"))
-	;
-      else if (unformat (input, "%d", &port))
+      else if (unformat (input, "ipv6"))
+	pr.punt.l4.af = AF_IP6;
+      else if (unformat (input, "ip6"))
+	pr.punt.l4.af = AF_IP6;
+      else if (unformat (input, "%d", &pr.punt.l4.port))
 	;
       else if (unformat (input, "udp"))
-	protocol = IP_PROTOCOL_UDP;
+	pr.punt.l4.protocol = IP_PROTOCOL_UDP;
       else if (unformat (input, "tcp"))
-	protocol = IP_PROTOCOL_TCP;
+	pr.punt.l4.protocol = IP_PROTOCOL_TCP;
       else
 	{
 	  error = clib_error_return (0, "parse error: '%U'",
@@ -805,7 +392,7 @@ punt_cli (vlib_main_t * vm,
     }
 
   /* punt both IPv6 and IPv4 when used in CLI */
-  error = vnet_punt_add_del (vm, ~0, protocol, port, is_add);
+  error = vnet_punt_add_del (vm, &pr, is_add);
   if (error)
     {
       clib_error_report (error);
@@ -843,28 +430,36 @@ VLIB_CLI_COMMAND (punt_command, static) = {
 };
 /* *INDENT-ON* */
 
-#ifndef CLIB_MARCH_VARIANT
 static clib_error_t *
 punt_socket_register_cmd (vlib_main_t * vm,
 			  unformat_input_t * input, vlib_cli_command_t * cmd)
 {
-  bool is_ipv4 = true;
-  u32 protocol = ~0;
-  u32 port = ~0;
   u8 *socket_name = 0;
   clib_error_t *error = NULL;
+  /* *INDENT-OFF* */
+  punt_reg_t pr = {
+    .punt = {
+      .l4 = {
+        .af = AF_IP4,
+        .port = ~0,
+        .protocol = ~0,
+      },
+    },
+    .type = PUNT_TYPE_L4,
+  };
+  /* *INDENT-ON* */
 
   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
     {
       if (unformat (input, "ipv4"))
 	;
       else if (unformat (input, "ipv6"))
-	is_ipv4 = false;
+	pr.punt.l4.af = AF_IP6;
       else if (unformat (input, "udp"))
-	protocol = IP_PROTOCOL_UDP;
+	pr.punt.l4.protocol = IP_PROTOCOL_UDP;
       else if (unformat (input, "tcp"))
-	protocol = IP_PROTOCOL_TCP;
-      else if (unformat (input, "%d", &port))
+	pr.punt.l4.protocol = IP_PROTOCOL_TCP;
+      else if (unformat (input, "%d", &pr.punt.l4.port))
 	;
       else if (unformat (input, "socket %s", &socket_name))
 	;
@@ -876,9 +471,8 @@ punt_socket_register_cmd (vlib_main_t * vm,
 	}
     }
 
-  error =
-    vnet_punt_socket_add (vm, 1, is_ipv4, protocol, port,
-			  (char *) socket_name);
+  error = vnet_punt_socket_add (vm, 1, &pr, (char *) socket_name);
+
 done:
   return error;
 }
@@ -903,22 +497,31 @@ punt_socket_deregister_cmd (vlib_main_t * vm,
 			    unformat_input_t * input,
 			    vlib_cli_command_t * cmd)
 {
-  bool is_ipv4 = true;
-  u32 protocol = ~0;
-  u32 port = ~0;
   clib_error_t *error = NULL;
+  /* *INDENT-OFF* */
+  punt_reg_t pr = {
+    .punt = {
+      .l4 = {
+        .af = AF_IP4,
+        .port = ~0,
+        .protocol = ~0,
+      },
+    },
+    .type = PUNT_TYPE_L4,
+  };
+  /* *INDENT-ON* */
 
   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
     {
       if (unformat (input, "ipv4"))
 	;
       else if (unformat (input, "ipv6"))
-	is_ipv4 = false;
+	pr.punt.l4.af = AF_IP6;
       else if (unformat (input, "udp"))
-	protocol = IP_PROTOCOL_UDP;
+	pr.punt.l4.protocol = IP_PROTOCOL_UDP;
       else if (unformat (input, "tcp"))
-	protocol = IP_PROTOCOL_TCP;
-      else if (unformat (input, "%d", &port))
+	pr.punt.l4.protocol = IP_PROTOCOL_TCP;
+      else if (unformat (input, "%d", &pr.punt.l4.port))
 	;
       else
 	{
@@ -928,7 +531,7 @@ punt_socket_deregister_cmd (vlib_main_t * vm,
 	}
     }
 
-  error = vnet_punt_socket_del (vm, is_ipv4, protocol, port);
+  error = vnet_punt_socket_del (vm, &pr);
 done:
   return error;
 }
@@ -948,85 +551,90 @@ VLIB_CLI_COMMAND (punt_socket_deregister_command, static) =
 };
 /* *INDENT-ON* */
 
-punt_socket_detail_t *
-punt_socket_entries (u8 ipv)
+void
+punt_client_walk (punt_type_t pt, punt_client_walk_cb_t cb, void *ctx)
 {
   punt_main_t *pm = &punt_main;
-  punt_client_t *pc;
-  punt_socket_detail_t *ps = 0;
-  bool is_valid;
-
-  punt_client_t *v = !ipv ? pm->clients_by_dst_port4 :
-    pm->clients_by_dst_port6;
 
-  vec_foreach (pc, v)
-  {
-    if (pc && pc->port != 0)
+  switch (pt)
+    {
+    case PUNT_TYPE_L4:
+      {
+	u32 pci;
+	u16 port;
+
+        /* *INDENT-OFF* */
+        hash_foreach(port, pci, pm->db.clients_by_l4_port,
+        ({
+          cb (pool_elt_at_index(pm->punt_client_pool, pci), ctx);
+        }));
+        /* *INDENT-ON* */
+	break;
+      }
+    case PUNT_TYPE_EXCEPTION:
       {
-	is_valid = false;
-	if (pc->protocol == IP_PROTOCOL_UDP)
-	  {
-	    is_valid = udp_is_valid_dst_port (pc->port, !ipv);
-	  }
-	if (is_valid)
-	  {
-	    punt_socket_detail_t detail = {
-	      .ipv = ipv,
-	      .l4_protocol = pc->protocol,
-	      .l4_port = pc->port
-	    };
-	    memcpy (detail.pathname, pc->caddr.sun_path,
-		    sizeof (pc->caddr.sun_path));
-	    vec_add1 (ps, detail);
-	  }
+	u32 *pci;
+
+	vec_foreach (pci, pm->db.clients_by_exception)
+	{
+	  if (~0 != *pci)
+	    cb (pool_elt_at_index (pm->punt_client_pool, *pci), ctx);
+	}
+
+	break;
       }
-  }
-  return ps;
+    }
 }
 
-u8 *
-format_punt_socket (u8 * s, va_list * args)
+static u8 *
+format_punt_client (u8 * s, va_list * args)
 {
-  punt_client_t *clients = va_arg (*args, punt_client_t *);
-  u8 *is_ipv6 = va_arg (*args, u8 *);
-  punt_client_t *pc;
-  bool is_valid;
+  punt_client_t *pc = va_arg (*args, punt_client_t *);
 
-  vec_foreach (pc, clients)
-  {
-    if (pc && pc->port != 0)
-      {
-	is_valid = false;
-	if (pc->protocol == IP_PROTOCOL_UDP)
-	  {
-	    is_valid = udp_is_valid_dst_port (pc->port, !(*is_ipv6));
-	  }
-	if (is_valid)
-	  {
-	    s = format (s, " punt %s port %d to socket %s \n",
-			(pc->protocol == IP_PROTOCOL_UDP) ? "UDP" : "TCP",
-			pc->port, pc->caddr.sun_path);
-	  }
-      }
-  }
+  s = format (s, " punt ");
+
+  switch (pc->reg.type)
+    {
+    case PUNT_TYPE_L4:
+      s = format (s, "%U %U port %d",
+		  format_ip_address_family, pc->reg.punt.l4.af,
+		  format_ip_protocol, pc->reg.punt.l4.protocol,
+		  pc->reg.punt.l4.port);
+      break;
+    case PUNT_TYPE_EXCEPTION:
+      s = format (s, " %U", format_vlib_punt_reason,
+		  pc->reg.punt.exception.reason);
+      break;
+    }
+
+  s = format (s, " to socket %s \n", pc->caddr.sun_path);
 
   return (s);
 }
 
+static walk_rc_t
+punt_client_show_one (const punt_client_t * pc, void *ctx)
+{
+  vlib_cli_output (ctx, "%U", format_punt_client, pc);
+
+  return (WALK_CONTINUE);
+}
+
 static clib_error_t *
 punt_socket_show_cmd (vlib_main_t * vm,
 		      unformat_input_t * input, vlib_cli_command_t * cmd)
 {
-  u8 is_ipv6;
-  punt_main_t *pm = &punt_main;
   clib_error_t *error = NULL;
+  punt_type_t pt;
+
+  pt = PUNT_TYPE_L4;
 
   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
     {
-      if (unformat (input, "ipv4"))
-	is_ipv6 = 0;
-      else if (unformat (input, "ipv6"))
-	is_ipv6 = 1;
+      if (unformat (input, "exception"))
+	pt = PUNT_TYPE_EXCEPTION;
+      else if (unformat (input, "l4"))
+	pt = PUNT_TYPE_L4;
       else
 	{
 	  error = clib_error_return (0, "parse error: '%U'",
@@ -1035,9 +643,7 @@ punt_socket_show_cmd (vlib_main_t * vm,
 	}
     }
 
-  punt_client_t *v =
-    is_ipv6 ? pm->clients_by_dst_port6 : pm->clients_by_dst_port4;
-  vlib_cli_output (vm, "%U", format_punt_socket, v, &is_ipv6);
+  punt_client_walk (pt, punt_client_show_one, vm);
 
 done:
   return (error);
@@ -1053,7 +659,7 @@ VLIB_CLI_COMMAND (show_punt_socket_registration_command, static) =
 {
   .path = "show punt socket registrations",
   .function = punt_socket_show_cmd,
-  .short_help = "show punt socket registrations [ipv4|ipv6]",
+  .short_help = "show punt socket registrations [l4|exception]",
   .is_mp_safe = 1,
 };
 /* *INDENT-ON* */
@@ -1061,24 +667,22 @@ VLIB_CLI_COMMAND (show_punt_socket_registration_command, static) =
 clib_error_t *
 ip_punt_init (vlib_main_t * vm)
 {
+  clib_error_t *error = NULL;
   punt_main_t *pm = &punt_main;
 
-  pm->clients_by_dst_port6 = sparse_vec_new
-    (sizeof (pm->clients_by_dst_port6[0]),
-     BITS (((udp_header_t *) 0)->dst_port));
-  pm->clients_by_dst_port4 = sparse_vec_new
-    (sizeof (pm->clients_by_dst_port4[0]),
-     BITS (((udp_header_t *) 0)->dst_port));
-
   pm->is_configured = false;
-  pm->interface_output_node = vlib_get_node_by_name (vm,
-						     (u8 *)
-						     "interface-output");
-  return 0;
+  pm->interface_output_node =
+    vlib_get_node_by_name (vm, (u8 *) "interface-output");
+
+  if ((error = vlib_call_init_function (vm, punt_init)))
+    return error;
+
+  pm->hdl = vlib_punt_client_register ("ip-punt");
+
+  return (error);
 }
 
 VLIB_INIT_FUNCTION (ip_punt_init);
-#endif /* CLIB_MARCH_VARIANT */
 
 static clib_error_t *
 punt_config (vlib_main_t * vm, unformat_input_t * input)
@@ -1124,6 +728,15 @@ punt_config (vlib_main_t * vm, unformat_input_t * input)
       return clib_error_return (0, "bind error");
     }
 
+  int n_bytes = 0x10000;
+
+  if (setsockopt
+      (pm->socket_fd, SOL_SOCKET, SO_SNDBUF, &n_bytes,
+       sizeof (n_bytes)) == -1)
+    {
+      return clib_error_return (0, "setsockopt error");
+    }
+
   /* Register socket */
   clib_file_main_t *fm = &file_main;
   clib_file_t template = { 0 };
diff --git a/src/vnet/ip/punt.h b/src/vnet/ip/punt.h
index 0518b2b91ef..a77e6330813 100644
--- a/src/vnet/ip/punt.h
+++ b/src/vnet/ip/punt.h
@@ -22,23 +22,51 @@
 
 #include <linux/un.h>
 #include <stdbool.h>
+#include <vnet/ip/ip.h>
 
-typedef enum
+#define foreach_punt_type \
+  _(L4, "l4")             \
+  _(EXCEPTION, "exception")
+
+typedef enum punt_type_t_
+{
+#define _(v, s) PUNT_TYPE_##v,
+  foreach_punt_type
+#undef _
+} punt_type_t;
+
+typedef struct punt_l4_t_
+{
+  ip_address_family_t af;
+  ip_protocol_t protocol;
+  u16 port;
+} punt_l4_t;
+
+typedef struct punt_exception_t_
 {
-#define punt_error(n,s) PUNT_ERROR_##n,
-#include <vnet/ip/punt_error.def>
-#undef punt_error
-  PUNT_N_ERROR,
-} punt_error_t;
+  vlib_punt_reason_t reason;
+} punt_exception_t;
 
+typedef struct punt_union_t_
+{
+  punt_exception_t exception;
+  punt_l4_t l4;
+} punt_union_t;
 
-clib_error_t *vnet_punt_add_del (vlib_main_t * vm, u8 ipv,
-				 u8 protocol, u16 port, bool is_add);
-clib_error_t *vnet_punt_socket_add (vlib_main_t * vm, u32 header_version,
-				    bool is_ip4, u8 protocol, u16 port,
+typedef struct punt_reg_t_
+{
+  punt_type_t type;
+  punt_union_t punt;
+} punt_reg_t;
+
+
+clib_error_t *vnet_punt_add_del (vlib_main_t * vm,
+				 const punt_reg_t * pr, bool is_add);
+clib_error_t *vnet_punt_socket_add (vlib_main_t * vm,
+				    u32 header_version,
+				    const punt_reg_t * pr,
 				    char *client_pathname);
-clib_error_t *vnet_punt_socket_del (vlib_main_t * vm, bool is_ip4,
-				    u8 l4_protocol, u16 port);
+clib_error_t *vnet_punt_socket_del (vlib_main_t * vm, const punt_reg_t * pr);
 char *vnet_punt_get_server_pathname (void);
 
 enum punt_action_e
@@ -64,34 +92,83 @@ typedef struct __attribute__ ((packed))
  */
 typedef struct
 {
-  u8 protocol;
-  u16 port;
+  punt_reg_t reg;
   struct sockaddr_un caddr;
 } punt_client_t;
 
+typedef struct punt_client_db_t_
+{
+  void *clients_by_l4_port;
+  u32 *clients_by_exception;
+} punt_client_db_t;
+
 typedef struct
 {
   int socket_fd;
   char sun_path[sizeof (struct sockaddr_un)];
-  punt_client_t *clients_by_dst_port4;
-  punt_client_t *clients_by_dst_port6;
+  punt_client_db_t db;
+  punt_client_t *punt_client_pool;
   u32 clib_file_index;
   bool is_configured;
   vlib_node_t *interface_output_node;
   u32 *ready_fds;
   u32 *rx_buffers;
+  vlib_punt_hdl_t hdl;
 } punt_main_t;
+
 extern punt_main_t punt_main;
 
-typedef struct punt_socket_detail_t_
+typedef walk_rc_t (*punt_client_walk_cb_t) (const punt_client_t * pc,
+					    void *ctx);
+extern void punt_client_walk (punt_type_t pt,
+			      punt_client_walk_cb_t cb, void *ctx);
+
+/*
+ * inlines for the data-plane
+ */
+static_always_inline u32
+punt_client_l4_mk_key (ip_address_family_t af, u16 port)
+{
+  return (af << BITS (port) | port);
+}
+
+static_always_inline punt_client_t *
+punt_client_l4_get (ip_address_family_t af, u16 port)
+{
+  punt_main_t *pm = &punt_main;
+  uword *p;
+
+  p = hash_get (pm->db.clients_by_l4_port, punt_client_l4_mk_key (af, port));
+
+  if (p)
+    return (pool_elt_at_index (pm->punt_client_pool, p[0]));
+
+  return (NULL);
+}
+
+static_always_inline punt_client_t *
+punt_client_exception_get (vlib_punt_reason_t reason)
 {
-  u8 ipv;
-  u8 l4_protocol;
-  u16 l4_port;
-  u8 pathname[108];
-} punt_socket_detail_t;
+  punt_main_t *pm = &punt_main;
+  u32 pci;
+
+  if (reason >= vec_len (pm->db.clients_by_exception))
+    return (NULL);
+
+  pci = pm->db.clients_by_exception[reason];
+
+  if (~0 != pci)
+    return (pool_elt_at_index (pm->punt_client_pool, pci));
+
+  return (NULL);
+}
+
+extern vlib_node_registration_t udp4_punt_node;
+extern vlib_node_registration_t udp6_punt_node;
+extern vlib_node_registration_t udp4_punt_socket_node;
+extern vlib_node_registration_t udp6_punt_socket_node;
+extern vlib_node_registration_t punt_socket_rx_node;
 
-punt_socket_detail_t *punt_socket_entries (u8 ipv);
 #endif
 
 /*
diff --git a/src/vnet/ip/punt.md b/src/vnet/ip/punt.md
new file mode 100644
index 00000000000..2bbb5f6b97e
--- /dev/null
+++ b/src/vnet/ip/punt.md
@@ -0,0 +1,82 @@
+.. _punt:
+
+Punting Packets
+===============
+
+.. toctree::
+
+Overview
+________
+
+To 'punt' can mean different things to different people. In VPP the
+data-plane punts when a packet cannot be handled by any further
+nodes. Punt differs from drop, in that VPP is giving other elements of
+the system the opportunity to handle this packet.
+
+A popular meaning of punt is to send packets to the user/control-plane.
+This is specific option of the more general case above, where VPP is
+handing the packet to the control-plane for further prosessing.
+
+The Punt Infrastructe
+---------------------
+
+Exception packets are those that a given node cannot handle via normal
+mecahnisms.
+Punting of exception packets is handled via the VLIB 'punt
+infra'. There are two types of nodes; sources and sinks. Sources
+allocate a punt 'reason' from the infrastructre and load time. When
+they encouter an exception during switch time it will tag the packet
+with the reason and ship the packet of the the punt-dispatch node. A
+sink will register with the punt infra at load time so it can receive
+packets that were punted for that reason. If no sinks are registerd
+for a given reason the packet is dropped, if multiple sinks register
+the packets are replicated.
+
+This mechanism allows us to extend the system to deal with packets
+that the source node would otherise drop.
+
+
+Punting to the Control Plane
+----------------------------
+
+Active Punt
+-----------
+
+The user/control-plane specifies that this is the type of packet I
+want to receive and this is where I want it sent.
+
+Currently there exists 3 ways to describe how to match/classify the
+packets to be punted:
+...
+ 1) a matching UDP port
+ 2) a matching IP protocol (i.e. OSPF)
+ 3) a matching punt excpetion reason (see above)
+...
+
+Depending on the type/classification of the packet to be punted, that
+active punt will register itself into the VLIB graph to receive those
+packets. For example, if it's a packet matching a UDP port then it
+will hook into the UDP port dispatch functions; udp_register_port().
+
+There exists only one sink for passive punt, a unix domain socket. But
+more work is underway in this area.
+
+see the API in: vnet/ip/punt.api
+
+
+
+Passive Punt
+------------
+
+VPP input packet processing can be described as a series of
+classifiers. For example, a sequence of input classifications could
+be, is it IP? is it for-us? is it UDP? is it a known UDP-port? If at
+some point in this pipline VPP has no further classifications to make,
+then the packet can be punted, which means sent to ipX-punt node. This
+is described as passive since the control-plane is thus receiving
+every packet that VPP does not itself handle.
+For passive punt the user can specify where the packets should be
+sent and whether/how they should be policed/rate-limited.
+
+see the API in: vnet/ip/ip.api
+
diff --git a/src/vnet/ip/punt_api.c b/src/vnet/ip/punt_api.c
index ecb461bcdda..95fff714b46 100644
--- a/src/vnet/ip/punt_api.c
+++ b/src/vnet/ip/punt_api.c
@@ -20,6 +20,7 @@
 #include <vnet/vnet.h>
 #include <vlibmemory/api.h>
 #include <vnet/ip/punt.h>
+#include <vnet/ip/ip_types_api.h>
 
 #include <vnet/vnet_msg_enum.h>
 
@@ -43,107 +44,226 @@
 _(SET_PUNT, set_punt)                                                   \
 _(PUNT_SOCKET_REGISTER, punt_socket_register)                           \
 _(PUNT_SOCKET_DEREGISTER, punt_socket_deregister)                       \
-_(PUNT_DUMP, punt_dump)                                                 \
-_(PUNT_SOCKET_DUMP, punt_socket_dump)
+_(PUNT_SOCKET_DUMP, punt_socket_dump)                                   \
+_(PUNT_REASON_DUMP, punt_reason_dump)
+
+static int
+vl_api_punt_type_decode (vl_api_punt_type_t in, punt_type_t * out)
+{
+  in = clib_net_to_host_u32 (in);
+
+  switch (in)
+    {
+#define _(v, s)                                 \
+      case PUNT_API_TYPE_##v:                   \
+        *out = PUNT_TYPE_##v;                   \
+        return (0);
+      foreach_punt_type
+#undef _
+    }
+
+  return (-1);
+}
+
+static vl_api_punt_type_t
+vl_api_punt_type_encode (punt_type_t in)
+{
+  vl_api_punt_type_t pt = PUNT_API_TYPE_L4;
+
+  switch (in)
+    {
+#define _(v, s)                                   \
+      case PUNT_TYPE_##v:                         \
+        pt = PUNT_API_TYPE_##v;                   \
+        break;
+      foreach_punt_type
+#undef _
+    }
+
+  return (clib_host_to_net_u32 (pt));
+}
+
+static int
+vl_api_punt_l4_decode (const vl_api_punt_l4_t * in, punt_l4_t * out)
+{
+  int rv;
+
+  rv = ip_address_family_decode (in->af, &out->af);
+  rv += ip_proto_decode (in->protocol, &out->protocol);
+  out->port = clib_net_to_host_u16 (in->port);
+
+  return (rv);
+}
+
+static int
+vl_api_punt_exception_decode (const vl_api_punt_exception_t * in,
+			      punt_exception_t * out)
+{
+  int rv;
+
+  out->reason = clib_net_to_host_u32 (in->id);
+  rv = vlib_punt_reason_validate (out->reason);
+
+  return (rv);
+}
+
+static int
+vl_api_punt_decode (const vl_api_punt_t * in, punt_reg_t * out)
+{
+  int rv;
+
+  rv = vl_api_punt_type_decode (in->type, &out->type);
+
+  if (rv)
+    return (rv);
+
+  switch (out->type)
+    {
+    case PUNT_TYPE_L4:
+      return (vl_api_punt_l4_decode (&in->punt.l4, &out->punt.l4));
+    case PUNT_TYPE_EXCEPTION:
+      return (vl_api_punt_exception_decode (&in->punt.exception,
+					    &out->punt.exception));
+    }
+
+  return (-1);
+}
+
+static void
+vl_api_punt_l4_encode (const punt_l4_t * in, vl_api_punt_l4_t * out)
+{
+  out->af = ip_address_family_encode (in->af);
+  out->protocol = ip_proto_encode (in->protocol);
+  out->port = clib_net_to_host_u16 (in->port);
+}
+
+static void
+vl_api_punt_exception_encode (const punt_exception_t * in,
+			      vl_api_punt_exception_t * out)
+{
+  out->id = clib_host_to_net_u32 (in->reason);
+}
+
+static void
+vl_api_punt_encode (const punt_reg_t * in, vl_api_punt_t * out)
+{
+  out->type = vl_api_punt_type_encode (in->type);
+
+  switch (in->type)
+    {
+    case PUNT_TYPE_L4:
+      vl_api_punt_l4_encode (&in->punt.l4, &out->punt.l4);
+      break;
+    case PUNT_TYPE_EXCEPTION:
+      vl_api_punt_exception_encode (&in->punt.exception,
+				    &out->punt.exception);
+      break;
+    }
+}
 
 static void
 vl_api_set_punt_t_handler (vl_api_set_punt_t * mp)
 {
   vl_api_set_punt_reply_t *rmp;
   vlib_main_t *vm = vlib_get_main ();
-  int rv = 0;
   clib_error_t *error;
+  punt_reg_t pr;
+  int rv;
+
+  rv = vl_api_punt_decode (&mp->punt, &pr);
 
-  error = vnet_punt_add_del (vm, mp->punt.ipv, mp->punt.l4_protocol,
-			     ntohs (mp->punt.l4_port), mp->is_add);
+  if (rv)
+    goto out;
+
+  error = vnet_punt_add_del (vm, &pr, mp->is_add);
   if (error)
     {
       rv = -1;
       clib_error_report (error);
     }
 
+out:
   REPLY_MACRO (VL_API_SET_PUNT_REPLY);
 }
 
 static void
-vl_api_punt_dump_t_handler (vl_api_punt_dump_t * mp)
-{
-
-}
-
-static void
 vl_api_punt_socket_register_t_handler (vl_api_punt_socket_register_t * mp)
 {
   vl_api_punt_socket_register_reply_t *rmp;
   vlib_main_t *vm = vlib_get_main ();
-  int rv = 0;
   clib_error_t *error;
-  vl_api_registration_t *reg;
+  punt_reg_t pr;
+  int rv;
+
+  rv = vl_api_punt_decode (&mp->punt, &pr);
+
+  if (rv)
+    return;
 
   error = vnet_punt_socket_add (vm, ntohl (mp->header_version),
-				mp->punt.ipv, mp->punt.l4_protocol,
-				ntohs (mp->punt.l4_port),
-				(char *) mp->pathname);
+				&pr, (char *) mp->pathname);
   if (error)
     {
       rv = -1;
       clib_error_report (error);
     }
 
-  reg = vl_api_client_index_to_registration (mp->client_index);
-  if (!reg)
-    return;
-
-  rmp = vl_msg_api_alloc (sizeof (*rmp));
-  rmp->_vl_msg_id = htons (VL_API_PUNT_SOCKET_REGISTER_REPLY);
-  rmp->context = mp->context;
-  rmp->retval = htonl (rv);
   char *p = vnet_punt_get_server_pathname ();
-  /* Abstract pathnames start with \0 */
-  memcpy ((char *) rmp->pathname, p, sizeof (rmp->pathname));
-  vl_api_send_msg (reg, (u8 *) rmp);
+
+  /* *INDENT-OFF* */
+  REPLY_MACRO2 (VL_API_PUNT_SOCKET_REGISTER_REPLY,
+  ({
+    memcpy ((char *) rmp->pathname, p, sizeof (rmp->pathname));
+  }));
+  /* *INDENT-ON* */
 }
 
-void
-send_punt_socket_details (vl_api_registration_t * reg,
-			  u32 context, punt_socket_detail_t * p)
+typedef struct punt_socket_send_ctx_t_
+{
+  vl_api_registration_t *reg;
+  u32 context;
+} punt_socket_send_ctx_t;
+
+static walk_rc_t
+vl_api_punt_socket_send_details (const punt_client_t * pc, void *args)
 {
+  punt_socket_send_ctx_t *ctx = args;
   vl_api_punt_socket_details_t *mp;
 
   mp = vl_msg_api_alloc (sizeof (*mp));
   if (!mp)
-    return;
+    return (WALK_STOP);
 
   clib_memset (mp, 0, sizeof (*mp));
   mp->_vl_msg_id = ntohs (VL_API_PUNT_SOCKET_DETAILS);
-  mp->context = context;
-  mp->punt.ipv = p->ipv;
-  mp->punt.l4_protocol = p->l4_protocol;
-  mp->punt.l4_port = htons (p->l4_port);
-  memcpy (mp->pathname, p->pathname, sizeof (p->pathname));
+  mp->context = ctx->context;
+  vl_api_punt_encode (&pc->reg, &mp->punt);
+  memcpy (mp->pathname, pc->caddr.sun_path, sizeof (pc->caddr.sun_path));
+
+  vl_api_send_msg (ctx->reg, (u8 *) mp);
 
-  vl_api_send_msg (reg, (u8 *) mp);
+  return (WALK_CONTINUE);
 }
 
 static void
 vl_api_punt_socket_dump_t_handler (vl_api_punt_socket_dump_t * mp)
 {
   vl_api_registration_t *reg;
-  punt_socket_detail_t *p, *ps;
-  int rv __attribute__ ((unused)) = 0;
+  punt_type_t pt;
+
+  if (0 != vl_api_punt_type_decode (mp->type, &pt))
+    return;
 
   reg = vl_api_client_index_to_registration (mp->client_index);
   if (!reg)
     return;
 
-  ps = punt_socket_entries (mp->is_ipv6);
-  /* *INDENT-OFF* */
-  vec_foreach (p, ps)
-  {
-    send_punt_socket_details (reg, mp->context, p);
-  }
-  /* *INDENT-ON* */
-  vec_free (ps);
+  punt_socket_send_ctx_t ctx = {
+    .reg = reg,
+    .context = mp->context,
+  };
+
+  punt_client_walk (pt, vl_api_punt_socket_send_details, &ctx);
 }
 
 static void
@@ -151,27 +271,69 @@ vl_api_punt_socket_deregister_t_handler (vl_api_punt_socket_deregister_t * mp)
 {
   vl_api_punt_socket_deregister_reply_t *rmp;
   vlib_main_t *vm = vlib_get_main ();
-  int rv = 0;
   clib_error_t *error;
-  vl_api_registration_t *reg;
+  punt_reg_t pr;
+  int rv;
+
+  rv = vl_api_punt_decode (&mp->punt, &pr);
 
-  error = vnet_punt_socket_del (vm, mp->punt.ipv, mp->punt.l4_protocol,
-				ntohs (mp->punt.l4_port));
+  if (rv)
+    goto out;
+
+  error = vnet_punt_socket_del (vm, &pr);
   if (error)
     {
       rv = -1;
       clib_error_report (error);
     }
 
+out:
+  REPLY_MACRO (VL_API_PUNT_SOCKET_DEREGISTER_REPLY);
+}
+
+typedef struct punt_reason_dump_walk_ctx_t_
+{
+  vl_api_registration_t *reg;
+  u32 context;
+} punt_reason_dump_walk_ctx_t;
+
+static int
+punt_reason_dump_walk_cb (vlib_punt_reason_t id, const u8 * name, void *args)
+{
+  punt_reason_dump_walk_ctx_t *ctx = args;
+  vl_api_punt_reason_details_t *mp;
+
+  mp = vl_msg_api_alloc (sizeof (*mp) + vec_len (name));
+  if (!mp)
+    return (0);
+
+  clib_memset (mp, 0, sizeof (*mp));
+  mp->_vl_msg_id = ntohs (VL_API_PUNT_REASON_DETAILS);
+
+  mp->context = ctx->context;
+  mp->reason.id = clib_host_to_net_u32 (id);
+  vl_api_to_api_string (vec_len (name), (char *) name, &mp->reason.name);
+
+  vl_api_send_msg (ctx->reg, (u8 *) mp);
+
+  return (1);
+}
+
+static void
+vl_api_punt_reason_dump_t_handler (vl_api_punt_reason_dump_t * mp)
+{
+  vl_api_registration_t *reg;
+
   reg = vl_api_client_index_to_registration (mp->client_index);
   if (!reg)
     return;
 
-  rmp = vl_msg_api_alloc (sizeof (*rmp));
-  rmp->_vl_msg_id = htons (VL_API_PUNT_SOCKET_DEREGISTER_REPLY);
-  rmp->context = mp->context;
-  rmp->retval = htonl (rv);
-  vl_api_send_msg (reg, (u8 *) rmp);
+  punt_reason_dump_walk_ctx_t ctx = {
+    .reg = reg,
+    .context = mp->context,
+  };
+
+  punt_reason_walk (punt_reason_dump_walk_cb, &ctx);
 }
 
 #define vl_msg_name_crc_list
diff --git a/src/vnet/ip/punt_node.c b/src/vnet/ip/punt_node.c
new file mode 100644
index 00000000000..53c8199342b
--- /dev/null
+++ b/src/vnet/ip/punt_node.c
@@ -0,0 +1,587 @@
+/*
+ * Copyright (c) 2016 Cisco 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 agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * 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.
+ */
+
+/**
+ * @file
+ * @brief Local TCP/IP stack punt infrastructure.
+ *
+ * Provides a set of VPP nodes together with the relevant APIs and CLI
+ * commands in order to adjust and dispatch packets from the VPP data plane
+ * to the local TCP/IP stack
+ */
+
+#include <vnet/ip/ip.h>
+#include <vlib/vlib.h>
+#include <vnet/pg/pg.h>
+#include <vnet/udp/udp.h>
+#include <vnet/tcp/tcp.h>
+#include <vnet/sctp/sctp.h>
+#include <vnet/ip/punt.h>
+#include <vlib/unix/unix.h>
+
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <sys/uio.h>
+#include <stdlib.h>
+
+typedef enum
+{
+#define punt_error(n,s) PUNT_ERROR_##n,
+#include <vnet/ip/punt_error.def>
+#undef punt_error
+  PUNT_N_ERROR,
+} punt_error_t;
+
+#define foreach_punt_next			\
+  _ (PUNT4, "ip4-punt")                         \
+  _ (PUNT6, "ip6-punt")
+
+typedef enum
+{
+#define _(s,n) PUNT_NEXT_##s,
+  foreach_punt_next
+#undef _
+    PUNT_N_NEXT,
+} punt_next_t;
+
+enum punt_socket_rx_next_e
+{
+  PUNT_SOCKET_RX_NEXT_INTERFACE_OUTPUT,
+  PUNT_SOCKET_RX_NEXT_IP4_LOOKUP,
+  PUNT_SOCKET_RX_NEXT_IP6_LOOKUP,
+  PUNT_SOCKET_RX_N_NEXT
+};
+
+#define punt_next_punt(is_ip4) (is_ip4 ? PUNT_NEXT_PUNT4 : PUNT_NEXT_PUNT6)
+
+/** @brief IPv4/IPv6 UDP punt node main loop.
+
+    This is the main loop inline function for IPv4/IPv6 UDP punt
+    transition node.
+
+    @param vm vlib_main_t corresponding to the current thread
+    @param node vlib_node_runtime_t
+    @param frame vlib_frame_t whose contents should be dispatched
+    @param is_ipv4 indicates if called for IPv4 or IPv6 node
+*/
+always_inline uword
+udp46_punt_inline (vlib_main_t * vm,
+		   vlib_node_runtime_t * node,
+		   vlib_frame_t * from_frame, int is_ip4)
+{
+  u32 n_left_from, *from, *to_next;
+  word advance;
+
+  from = vlib_frame_vector_args (from_frame);
+  n_left_from = from_frame->n_vectors;
+
+  /* udp[46]_lookup hands us the data payload, not the IP header */
+  if (is_ip4)
+    advance = -(sizeof (ip4_header_t) + sizeof (udp_header_t));
+  else
+    advance = -(sizeof (ip6_header_t) + sizeof (udp_header_t));
+
+  while (n_left_from > 0)
+    {
+      u32 n_left_to_next;
+
+      vlib_get_next_frame (vm, node, punt_next_punt (is_ip4), to_next,
+			   n_left_to_next);
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  u32 bi0;
+	  vlib_buffer_t *b0;
+
+	  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);
+	  vlib_buffer_advance (b0, advance);
+	  b0->error = node->errors[PUNT_ERROR_UDP_PORT];
+	}
+
+      vlib_put_next_frame (vm, node, punt_next_punt (is_ip4), n_left_to_next);
+    }
+
+  return from_frame->n_vectors;
+}
+
+static char *punt_error_strings[] = {
+#define punt_error(n,s) s,
+#include "punt_error.def"
+#undef punt_error
+};
+
+/** @brief IPv4 UDP punt node.
+    @node ip4-udp-punt
+
+    This is the IPv4 UDP punt transition node. It is registered as a next
+    node for the "ip4-udp-lookup" handling UDP port(s) requested for punt.
+    The buffer's current data pointer is adjusted to the original packet
+    IPv4 header. All buffers are dispatched to "error-punt".
+
+    @param vm vlib_main_t corresponding to the current thread
+    @param node vlib_node_runtime_t
+    @param frame vlib_frame_t whose contents should be dispatched
+
+    @par Graph mechanics: next index usage
+
+    @em Sets:
+    - <code>vnet_buffer(b)->current_data</code>
+    - <code>vnet_buffer(b)->current_len</code>
+
+    <em>Next Index:</em>
+    - Dispatches the packet to the "error-punt" node
+*/
+VLIB_NODE_FN (udp4_punt_node) (vlib_main_t * vm,
+			       vlib_node_runtime_t * node,
+			       vlib_frame_t * from_frame)
+{
+  return udp46_punt_inline (vm, node, from_frame, 1 /* is_ip4 */ );
+}
+
+/** @brief IPv6 UDP punt node.
+    @node ip6-udp-punt
+
+    This is the IPv6 UDP punt transition node. It is registered as a next
+    node for the "ip6-udp-lookup" handling UDP port(s) requested for punt.
+    The buffer's current data pointer is adjusted to the original packet
+    IPv6 header. All buffers are dispatched to "error-punt".
+
+    @param vm vlib_main_t corresponding to the current thread
+    @param node vlib_node_runtime_t
+    @param frame vlib_frame_t whose contents should be dispatched
+
+    @par Graph mechanics: next index usage
+
+    @em Sets:
+    - <code>vnet_buffer(b)->current_data</code>
+    - <code>vnet_buffer(b)->current_len</code>
+
+    <em>Next Index:</em>
+    - Dispatches the packet to the "error-punt" node
+*/
+VLIB_NODE_FN (udp6_punt_node) (vlib_main_t * vm,
+			       vlib_node_runtime_t * node,
+			       vlib_frame_t * from_frame)
+{
+  return udp46_punt_inline (vm, node, from_frame, 0 /* is_ip4 */ );
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (udp4_punt_node) = {
+  .name = "ip4-udp-punt",
+  /* Takes a vector of packets. */
+  .vector_size = sizeof (u32),
+
+  .n_errors = PUNT_N_ERROR,
+  .error_strings = punt_error_strings,
+
+  .n_next_nodes = PUNT_N_NEXT,
+  .next_nodes = {
+#define _(s,n) [PUNT_NEXT_##s] = n,
+     foreach_punt_next
+#undef _
+  },
+};
+
+VLIB_REGISTER_NODE (udp6_punt_node) = {
+  .name = "ip6-udp-punt",
+  /* Takes a vector of packets. */
+  .vector_size = sizeof (u32),
+
+  .n_errors = PUNT_N_ERROR,
+  .error_strings = punt_error_strings,
+
+  .n_next_nodes = PUNT_N_NEXT,
+  .next_nodes = {
+#define _(s,n) [PUNT_NEXT_##s] = n,
+     foreach_punt_next
+#undef _
+  },
+};
+/* *INDENT-ON* */
+
+typedef struct
+{
+  punt_client_t client;
+  u8 is_midchain;
+} udp_punt_trace_t;
+
+static u8 *
+format_udp_punt_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 *);
+  udp_punt_trace_t *t = va_arg (*args, udp_punt_trace_t *);
+  u32 indent = format_get_indent (s);
+  s = format (s, "to: %s", t->client.caddr.sun_path);
+  if (t->is_midchain)
+    {
+      s = format (s, "\n%U(buffer is part of chain)", format_white_space,
+		  indent);
+    }
+  return s;
+}
+
+always_inline uword
+punt_socket_inline (vlib_main_t * vm,
+		    vlib_node_runtime_t * node,
+		    vlib_frame_t * frame,
+		    punt_type_t pt, ip_address_family_t af)
+{
+  u32 *buffers = vlib_frame_vector_args (frame);
+  uword n_packets = frame->n_vectors;
+  struct iovec *iovecs = 0;
+  punt_main_t *pm = &punt_main;
+  int i;
+
+  u32 node_index = AF_IP4 == af ? udp4_punt_socket_node.index :
+    udp6_punt_socket_node.index;
+
+  for (i = 0; i < n_packets; i++)
+    {
+      struct iovec *iov;
+      vlib_buffer_t *b;
+      uword l;
+      punt_packetdesc_t packetdesc;
+      punt_client_t *c;
+
+      b = vlib_get_buffer (vm, buffers[i]);
+
+      if (PUNT_TYPE_L4 == pt)
+	{
+	  /* Reverse UDP Punt advance */
+	  udp_header_t *udp;
+	  if (AF_IP4 == af)
+	    {
+	      vlib_buffer_advance (b, -(sizeof (ip4_header_t) +
+					sizeof (udp_header_t)));
+	      ip4_header_t *ip = vlib_buffer_get_current (b);
+	      udp = (udp_header_t *) (ip + 1);
+	    }
+	  else
+	    {
+	      vlib_buffer_advance (b, -(sizeof (ip6_header_t) +
+					sizeof (udp_header_t)));
+	      ip6_header_t *ip = vlib_buffer_get_current (b);
+	      udp = (udp_header_t *) (ip + 1);
+	    }
+
+	  u16 port = clib_net_to_host_u16 (udp->dst_port);
+
+	  /*
+	   * Find registerered client
+	   * If no registered client, drop packet and count
+	   */
+	  c = punt_client_l4_get (af, port);
+	}
+      else if (PUNT_TYPE_EXCEPTION == pt)
+	{
+	  c = punt_client_exception_get (b->punt_reason);
+	}
+      else
+	c = NULL;
+
+      if (PREDICT_FALSE (NULL == c))
+	{
+	  vlib_node_increment_counter (vm, node_index,
+				       PUNT_ERROR_SOCKET_TX_ERROR, 1);
+	  goto error;
+	}
+
+      struct sockaddr_un *caddr = &c->caddr;
+
+      if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
+	{
+	  udp_punt_trace_t *t;
+	  t = vlib_add_trace (vm, node, b, sizeof (t[0]));
+	  clib_memcpy_fast (&t->client, c, sizeof (t->client));
+	}
+
+      /* Re-set iovecs if present. */
+      if (iovecs)
+	_vec_len (iovecs) = 0;
+
+      /* Add packet descriptor */
+      packetdesc.sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
+      packetdesc.action = 0;
+      vec_add2 (iovecs, iov, 1);
+      iov->iov_base = &packetdesc;
+      iov->iov_len = sizeof (packetdesc);
+
+      /** VLIB buffer chain -> Unix iovec(s). */
+      vlib_buffer_advance (b, -(sizeof (ethernet_header_t)));
+      vec_add2 (iovecs, iov, 1);
+      iov->iov_base = b->data + b->current_data;
+      iov->iov_len = l = b->current_length;
+
+      if (PREDICT_FALSE (b->flags & VLIB_BUFFER_NEXT_PRESENT))
+	{
+	  do
+	    {
+	      b = vlib_get_buffer (vm, b->next_buffer);
+	      if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED))
+		{
+		  udp_punt_trace_t *t;
+		  t = vlib_add_trace (vm, node, b, sizeof (t[0]));
+		  clib_memcpy_fast (&t->client, c, sizeof (t->client));
+		  t->is_midchain = 1;
+		}
+
+	      vec_add2 (iovecs, iov, 1);
+
+	      iov->iov_base = b->data + b->current_data;
+	      iov->iov_len = b->current_length;
+	      l += b->current_length;
+	    }
+	  while (b->flags & VLIB_BUFFER_NEXT_PRESENT);
+	}
+
+      struct msghdr msg = {
+	.msg_name = caddr,
+	.msg_namelen = sizeof (*caddr),
+	.msg_iov = iovecs,
+	.msg_iovlen = vec_len (iovecs),
+      };
+
+      if (sendmsg (pm->socket_fd, &msg, 0) < (ssize_t) l)
+	vlib_node_increment_counter (vm, node_index,
+				     PUNT_ERROR_SOCKET_TX_ERROR, 1);
+      else
+	vlib_node_increment_counter (vm, node_index, PUNT_ERROR_SOCKET_TX, 1);
+    }
+
+error:
+  vlib_buffer_free (vm, buffers, n_packets);
+
+  return n_packets;
+}
+
+static uword
+udp4_punt_socket (vlib_main_t * vm,
+		  vlib_node_runtime_t * node, vlib_frame_t * from_frame)
+{
+  return punt_socket_inline (vm, node, from_frame, PUNT_TYPE_L4, AF_IP4);
+}
+
+static uword
+udp6_punt_socket (vlib_main_t * vm,
+		  vlib_node_runtime_t * node, vlib_frame_t * from_frame)
+{
+  return punt_socket_inline (vm, node, from_frame, PUNT_TYPE_L4, AF_IP6);
+}
+
+static uword
+exception_punt_socket (vlib_main_t * vm,
+		       vlib_node_runtime_t * node, vlib_frame_t * from_frame)
+{
+  return punt_socket_inline (vm, node, from_frame,
+			     PUNT_TYPE_EXCEPTION, AF_IP4);
+}
+
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (udp4_punt_socket_node) = {
+  .function = udp4_punt_socket,
+  .name = "ip4-udp-punt-socket",
+  .format_trace = format_udp_punt_trace,
+  .flags = VLIB_NODE_FLAG_IS_DROP,
+  /* Takes a vector of packets. */
+  .vector_size = sizeof (u32),
+  .n_errors = PUNT_N_ERROR,
+  .error_strings = punt_error_strings,
+};
+VLIB_REGISTER_NODE (udp6_punt_socket_node) = {
+  .function = udp6_punt_socket,
+  .name = "ip6-udp-punt-socket",
+  .format_trace = format_udp_punt_trace,
+  .flags = VLIB_NODE_FLAG_IS_DROP,
+  .vector_size = sizeof (u32),
+  .n_errors = PUNT_N_ERROR,
+  .error_strings = punt_error_strings,
+};
+VLIB_REGISTER_NODE (exception_punt_socket_node) = {
+  .function = exception_punt_socket,
+  .name = "exception-punt-socket",
+  .format_trace = format_udp_punt_trace,
+  .flags = VLIB_NODE_FLAG_IS_DROP,
+  .vector_size = sizeof (u32),
+  .n_errors = PUNT_N_ERROR,
+  .error_strings = punt_error_strings,
+};
+/* *INDENT-ON* */
+
+typedef struct
+{
+  enum punt_action_e action;
+  u32 sw_if_index;
+} punt_trace_t;
+
+static u8 *
+format_punt_trace (u8 * s, va_list * va)
+{
+  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
+  CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *);
+  vnet_main_t *vnm = vnet_get_main ();
+  punt_trace_t *t = va_arg (*va, punt_trace_t *);
+  s = format (s, "%U Action: %d", format_vnet_sw_if_index_name,
+	      vnm, t->sw_if_index, t->action);
+  return s;
+}
+
+static uword
+punt_socket_rx_fd (vlib_main_t * vm, vlib_node_runtime_t * node, u32 fd)
+{
+  const uword buffer_size = vlib_buffer_get_default_data_size (vm);
+  u32 n_trace = vlib_get_trace_count (vm, node);
+  u32 next = node->cached_next_index;
+  u32 n_left_to_next, next_index;
+  u32 *to_next;
+  u32 error = PUNT_ERROR_NONE;
+  vlib_get_next_frame (vm, node, next, to_next, n_left_to_next);
+
+  /* $$$$ Only dealing with one buffer at the time for now */
+
+  u32 bi;
+  vlib_buffer_t *b;
+  punt_packetdesc_t packetdesc;
+  ssize_t size;
+  struct iovec io[2];
+
+  if (vlib_buffer_alloc (vm, &bi, 1) != 1)
+    {
+      error = PUNT_ERROR_NOBUFFER;
+      goto error;
+    }
+
+  b = vlib_get_buffer (vm, bi);
+  io[0].iov_base = &packetdesc;
+  io[0].iov_len = sizeof (packetdesc);
+  io[1].iov_base = b->data;
+  io[1].iov_len = buffer_size;
+
+  size = readv (fd, io, 2);
+  /* We need at least the packet descriptor plus a header */
+  if (size <= (int) (sizeof (packetdesc) + sizeof (ip4_header_t)))
+    {
+      vlib_buffer_free (vm, &bi, 1);
+      error = PUNT_ERROR_READV;
+      goto error;
+    }
+
+  b->flags = VNET_BUFFER_F_LOCALLY_ORIGINATED;
+  b->current_length = size - sizeof (packetdesc);
+
+  VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b);
+
+  switch (packetdesc.action)
+    {
+    case PUNT_L2:
+      vnet_buffer (b)->sw_if_index[VLIB_TX] = packetdesc.sw_if_index;
+      next_index = PUNT_SOCKET_RX_NEXT_INTERFACE_OUTPUT;
+      break;
+
+    case PUNT_IP4_ROUTED:
+      vnet_buffer (b)->sw_if_index[VLIB_RX] = packetdesc.sw_if_index;
+      vnet_buffer (b)->sw_if_index[VLIB_TX] = ~0;
+      next_index = PUNT_SOCKET_RX_NEXT_IP4_LOOKUP;
+      break;
+
+    case PUNT_IP6_ROUTED:
+      vnet_buffer (b)->sw_if_index[VLIB_RX] = packetdesc.sw_if_index;
+      vnet_buffer (b)->sw_if_index[VLIB_TX] = ~0;
+      next_index = PUNT_SOCKET_RX_NEXT_IP6_LOOKUP;
+      break;
+
+    default:
+      error = PUNT_ERROR_ACTION;
+      vlib_buffer_free (vm, &bi, 1);
+      goto error;
+    }
+
+  if (PREDICT_FALSE (n_trace > 0))
+    {
+      punt_trace_t *t;
+      vlib_trace_buffer (vm, node, next_index, b, 1 /* follow_chain */ );
+      vlib_set_trace_count (vm, node, --n_trace);
+      t = vlib_add_trace (vm, node, b, sizeof (*t));
+      t->sw_if_index = packetdesc.sw_if_index;
+      t->action = packetdesc.action;
+    }
+
+  to_next[0] = bi;
+  to_next++;
+  n_left_to_next--;
+
+  vlib_validate_buffer_enqueue_x1 (vm, node, next, to_next, n_left_to_next,
+				   bi, next_index);
+  vlib_put_next_frame (vm, node, next, n_left_to_next);
+  return 1;
+
+error:
+  vlib_node_increment_counter (vm, punt_socket_rx_node.index, error, 1);
+  return 0;
+}
+
+static uword
+punt_socket_rx (vlib_main_t * vm,
+		vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  punt_main_t *pm = &punt_main;
+  u32 total_count = 0;
+  int i;
+
+  for (i = 0; i < vec_len (pm->ready_fds); i++)
+    {
+      total_count += punt_socket_rx_fd (vm, node, pm->ready_fds[i]);
+      vec_del1 (pm->ready_fds, i);
+    }
+  return total_count;
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (punt_socket_rx_node) =
+{
+ .function = punt_socket_rx,
+ .name = "punt-socket-rx",
+ .type = VLIB_NODE_TYPE_INPUT,
+ .state = VLIB_NODE_STATE_INTERRUPT,
+ .vector_size = 1,
+ .n_errors = PUNT_N_ERROR,
+ .error_strings = punt_error_strings,
+ .n_next_nodes = PUNT_SOCKET_RX_N_NEXT,
+ .next_nodes = {
+    [PUNT_SOCKET_RX_NEXT_INTERFACE_OUTPUT] = "interface-output",
+    [PUNT_SOCKET_RX_NEXT_IP4_LOOKUP] = "ip4-lookup",
+    [PUNT_SOCKET_RX_NEXT_IP6_LOOKUP] = "ip6-lookup",
+  },
+ .format_trace = format_punt_trace,
+};
+/* *INDENT-ON* */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/vnet/ipsec/ipsec_punt.h b/src/vnet/ipsec/ipsec_punt.h
index 19943273154..4400ec9b4d2 100644
--- a/src/vnet/ipsec/ipsec_punt.h
+++ b/src/vnet/ipsec/ipsec_punt.h
@@ -18,11 +18,11 @@
 #include <vlib/vlib.h>
 
 #define foreach_ipsec_punt_reason                             \
-  _(IP4_SPI_0, "ip4-spi-0")                                   \
-  _(IP6_SPI_0, "ip6-spi-0")                                   \
-  _(IP4_SPI_UDP_0, "ip4-spi-o-udp-0")                         \
-  _(IP4_NO_SUCH_TUNNEL, "ip4-no-such-tunnel")                 \
-  _(IP6_NO_SUCH_TUNNEL, "ip6-no-such-tunnel")
+  _(IP4_SPI_0, "ipsec4-spi-0")                                \
+  _(IP6_SPI_0, "ipsec6-spi-0")                                \
+  _(IP4_SPI_UDP_0, "ipsec4-spi-o-udp-0")                      \
+  _(IP4_NO_SUCH_TUNNEL, "ipsec4-no-such-tunnel")              \
+  _(IP6_NO_SUCH_TUNNEL, "ipsec6-no-such-tunnel")
 
 typedef enum ipsec_punt_reason_t_
 {
diff --git a/src/vpp/api/custom_dump.c b/src/vpp/api/custom_dump.c
index e9175d6ddcd..32354e77e59 100644
--- a/src/vpp/api/custom_dump.c
+++ b/src/vpp/api/custom_dump.c
@@ -3404,13 +3404,17 @@ vl_api_set_punt_t_print (vl_api_set_punt_t * mp, void *handle)
 
   s = format (0, "SCRIPT: punt ");
 
-  if (mp->punt.ipv != (u8) ~ 0)
-    s = format (s, "ip %d ", mp->punt.ipv);
+  switch (clib_net_to_host_u32 (mp->punt.type))
+    {
+    case PUNT_API_TYPE_L4:
+      s = format (s, "%U", format_vl_api_address_family, mp->punt.punt.l4.af);
 
-  s = format (s, "protocol %d ", mp->punt.l4_protocol);
+      s = format (s, "protocol %d ", mp->punt.punt.l4.protocol);
 
-  if (mp->punt.l4_port != (u16) ~ 0)
-    s = format (s, "port %d ", ntohs (mp->punt.l4_port));
+      if (mp->punt.punt.l4.port != (u16) ~ 0)
+	s = format (s, "port %d ", ntohs (mp->punt.punt.l4.port));
+      break;
+    }
 
   if (!mp->is_add)
     s = format (s, "del ");
diff --git a/src/vpp/api/types.c b/src/vpp/api/types.c
index 427e9f0da3a..97dadbd4778 100644
--- a/src/vpp/api/types.c
+++ b/src/vpp/api/types.c
@@ -20,6 +20,19 @@
 #include <vat/vat.h>
 
 u8 *
+format_vl_api_address_family (u8 * s, va_list * args)
+{
+  vl_api_address_family_t af = va_arg (*args, vl_api_address_family_t);
+
+  if (ADDRESS_IP6 == clib_net_to_host_u32 (af))
+      s = format (s, "ip4");
+  else
+      s = format (s, "ip6");
+
+  return s;
+}
+
+u8 *
 format_vl_api_address (u8 * s, va_list * args)
 {
   const vl_api_address_t *addr = va_arg (*args, vl_api_address_t *);
@@ -110,6 +123,22 @@ unformat_vl_api_address (unformat_input_t * input, va_list * args)
 }
 
 uword
+unformat_vl_api_address_family (unformat_input_t * input,
+                                va_list * args)
+{
+  vl_api_address_family_t *af = va_arg (*args, vl_api_address_family_t *);
+
+  if (unformat (input, "ip4") || unformat (input, "ipv4"))
+      *af = clib_host_to_net_u32(ADDRESS_IP4);
+  else if (unformat (input, "ip6") || unformat (input, "ipv6"))
+      *af = clib_host_to_net_u32(ADDRESS_IP6);
+  else
+      return (0);
+
+  return (1);
+}
+
+uword
 unformat_vl_api_ip4_address (unformat_input_t * input, va_list * args)
 {
   vl_api_ip4_address_t *ip = va_arg (*args, vl_api_ip4_address_t *);
diff --git a/src/vpp/api/types.h b/src/vpp/api/types.h
index cf1b26d9bfc..a625e5d427a 100644
--- a/src/vpp/api/types.h
+++ b/src/vpp/api/types.h
@@ -27,12 +27,14 @@ const vl_api_mac_address_t VL_API_ZERO_MAC_ADDRESS;
 const vl_api_address_t VL_API_ZERO_ADDRESS;
 
 extern uword unformat_vl_api_mac_address (unformat_input_t * input, va_list * args);
+extern uword unformat_vl_api_address_family (unformat_input_t * input, va_list * args);
 extern uword unformat_vl_api_address (unformat_input_t * input, va_list * args);
 extern uword unformat_vl_api_ip4_address (unformat_input_t * input, va_list * args);
 extern uword unformat_vl_api_ip6_address (unformat_input_t * input, va_list * args);
 extern uword unformat_vl_api_prefix (unformat_input_t * input, va_list * args);
 
 extern u8 *format_vl_api_address (u8 * s, va_list * args);
+extern u8 *format_vl_api_address_family (u8 * s, va_list * args);
 extern u8 *format_vl_api_ip4_address (u8 * s, va_list * args);
 extern u8 *format_vl_api_ip6_address (u8 * s, va_list * args);
 extern u8 *format_vl_api_address_union (u8 * s, va_list * args);