VPP-1506: dump local punts and registered punt sockets

Change-Id: If7835e9b80ec9402404bfc8d271eb11a10ef992b
Signed-off-by: Pavel Kotucek <pavel.kotucek@pantheon.tech>

8 files changed, 489 insertions, 66 deletions

diff --git a/src/vnet/ip/punt.api b/src/vnet/ip/punt.api
index 4477e5c14e5..c8b222a211b 100644
--- a/src/vnet/ip/punt.api
+++ b/src/vnet/ip/punt.api
@@ -13,56 +13,85 @@
  * limitations under the License.
  */
 
-option version = "1.0.0";
+option version = "2.0.0";
+
+/** \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
+*/
+typeonly define punt
+{
+    u8 ipv;
+    u8 l4_protocol;
+    u16 l4_port;
+};
 
 /** \brief Punt traffic to the host
     @param client_index - opaque cookie to identify the sender
     @param context - sender context, to match reply w/ request
     @param is_add - add punt if non-zero, else delete
-    @param ipv - L3 protocol 4 - IPv4, 6 - IPv6, ~0 - All
-    @param l4_protocol - L4 protocol to be punted, only UDP (0x11) is supported
-    @param l4_port - TCP/UDP port to be punted
+    @param punt - punt definition, only UDP (0x11) is supported
 */
-autoreply define punt {
+autoreply define set_punt {
     u32 client_index;
     u32 context;
     u8 is_add;
-    u8 ipv;
-    u8 l4_protocol;
-    u16 l4_port;
+    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
     @param header_version - expected meta data header version (currently 1)
-    @param is_ip4 - L3 protocol 1 - IPv4, 0 - IPv6
-    @param l4_protocol - L4 protocol to be punted, only UDP (0x11) is supported
-    @param l4_port - TCP/UDP port to be punted
+    @param punt - punt definition
 */
 define punt_socket_register {
     u32 client_index;
     u32 context;
     u32 header_version;
-    u8 is_ip4;
-    u8 l4_protocol;
-    u16 l4_port;
+    vl_api_punt_t punt;
     u8 pathname[108]; /* Linux sun_path defined to be 108 bytes, see unix(7) */
 };
 
 define punt_socket_register_reply
 {
-  u32 context;
-  i32 retval;
-  u8 pathname[64];
+    u32 context;
+    i32 retval;
+    u8 pathname[64];
+};
+
+define punt_socket_dump
+{
+    u32 client_index;
+    u32 context;
+    u8 is_ipv6;
+};
+
+define punt_socket_details
+{
+    u32 context;
+    vl_api_punt_t punt;
+    u8 pathname[108];
 };
 
 autoreply define punt_socket_deregister {
     u32 client_index;
     u32 context;
-    u8 is_ip4;
-    u8 l4_protocol;
-    u16 l4_port;
+    vl_api_punt_t punt;
 };
 
 /*
diff --git a/src/vnet/ip/punt.c b/src/vnet/ip/punt.c
index d8c7d81a23a..c0902f346ff 100644
--- a/src/vnet/ip/punt.c
+++ b/src/vnet/ip/punt.c
@@ -35,10 +35,8 @@
 #include <stdio.h>
 #include <unistd.h>
 #include <sys/socket.h>
-#include <sys/un.h>
 #include <sys/uio.h>
 #include <stdlib.h>
-#include <stdbool.h>
 
 #define foreach_punt_next			\
   _ (PUNT4, "ip4-punt")                         \
@@ -261,7 +259,7 @@ punt_socket_get (bool is_ip4, u16 port)
   return NULL;
 }
 
-static void
+static int
 punt_socket_register (bool is_ip4, u8 protocol, u16 port,
 		      char *client_pathname)
 {
@@ -270,12 +268,18 @@ punt_socket_register (bool is_ip4, u8 protocol, u16 port,
   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;
 }
 
 /* $$$$ Just leaves the mapping in place for now */
@@ -424,6 +428,9 @@ udp46_punt_socket_inline (vlib_main_t * vm,
       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:
@@ -597,17 +604,25 @@ punt_socket_rx (vlib_main_t * vm,
   return total_count;
 }
 
+/* *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,};
+ .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* */
 
 static clib_error_t *
 punt_socket_read_ready (clib_file_t * uf)
@@ -645,7 +660,10 @@ vnet_punt_socket_add (vlib_main_t * vm, u32 header_version,
     return clib_error_return (0, "UDP port number required");
 
   /* Register client */
-  punt_socket_register (is_ip4, protocol, port, client_pathname);
+  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;
@@ -748,7 +766,7 @@ static clib_error_t *
 punt_cli (vlib_main_t * vm,
 	  unformat_input_t * input, vlib_cli_command_t * cmd)
 {
-  u32 port;
+  u32 port = ~0;
   bool is_add = true;
   u32 protocol = ~0;
   clib_error_t *error = NULL;
@@ -758,25 +776,9 @@ punt_cli (vlib_main_t * vm,
       if (unformat (input, "del"))
 	is_add = false;
       else if (unformat (input, "all"))
-	{
-	  /* punt both IPv6 and IPv4 when used in CLI */
-	  error = vnet_punt_add_del (vm, ~0, protocol, ~0, is_add);
-	  if (error)
-	    {
-	      clib_error_report (error);
-	      goto done;
-	    }
-	}
+	;
       else if (unformat (input, "%d", &port))
-	{
-	  /* punt both IPv6 and IPv4 when used in CLI */
-	  error = vnet_punt_add_del (vm, ~0, protocol, port, is_add);
-	  if (error)
-	    {
-	      clib_error_report (error);
-	      goto done;
-	    }
-	}
+	;
       else if (unformat (input, "udp"))
 	protocol = IP_PROTOCOL_UDP;
       else if (unformat (input, "tcp"))
@@ -788,6 +790,15 @@ punt_cli (vlib_main_t * vm,
 	  goto done;
 	}
     }
+
+  /* punt both IPv6 and IPv4 when used in CLI */
+  error = vnet_punt_add_del (vm, ~0, protocol, port, is_add);
+  if (error)
+    {
+      clib_error_report (error);
+      goto done;
+    }
+
 done:
   return error;
 }
@@ -820,6 +831,228 @@ VLIB_CLI_COMMAND (punt_command, static) = {
 };
 /* *INDENT-ON* */
 
+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;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "ipv4"))
+	;
+      else if (unformat (input, "ipv6"))
+	is_ipv4 = false;
+      else if (unformat (input, "udp"))
+	protocol = IP_PROTOCOL_UDP;
+      else if (unformat (input, "tcp"))
+	protocol = IP_PROTOCOL_TCP;
+      else if (unformat (input, "%d", &port))
+	;
+      else if (unformat (input, "socket %s", &socket_name))
+	;
+      else
+	{
+	  error = clib_error_return (0, "parse error: '%U'",
+				     format_unformat_error, input);
+	  goto done;
+	}
+    }
+
+  error =
+    vnet_punt_socket_add (vm, 1, is_ipv4, protocol, port,
+			  (char *) socket_name);
+  if (error)
+    {
+      goto done;
+    }
+done:
+  return error;
+}
+
+/*?
+ *
+ * @cliexpar
+ * @cliexcmd{punt socket register}
+ ?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (punt_socket_register_command, static) =
+{
+  .path = "punt socket register",
+  .function = punt_socket_register_cmd,
+  .short_help = "punt socket register [ipv4|ipv6] [udp|tcp]> <all | port-num1 [port-num2 ...]> <socket>",
+  .is_mp_safe = 1,
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+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;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "ipv4"))
+	;
+      else if (unformat (input, "ipv6"))
+	is_ipv4 = false;
+      else if (unformat (input, "udp"))
+	protocol = IP_PROTOCOL_UDP;
+      else if (unformat (input, "tcp"))
+	protocol = IP_PROTOCOL_TCP;
+      else if (unformat (input, "%d", &port))
+	;
+      else
+	{
+	  error = clib_error_return (0, "parse error: '%U'",
+				     format_unformat_error, input);
+	  goto done;
+	}
+    }
+
+  error = vnet_punt_socket_del (vm, is_ipv4, protocol, port);
+  if (error)
+    {
+      goto done;
+    }
+done:
+  return error;
+}
+
+/*?
+ *
+ * @cliexpar
+ * @cliexcmd{punt socket register}
+ ?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (punt_socket_deregister_command, static) =
+{
+  .path = "punt socket deregister",
+  .function = punt_socket_deregister_cmd,
+  .short_help = "punt socket deregister [ipv4|ipv6] [udp|tcp]> <all | port-num1 [port-num2 ...]>",
+  .is_mp_safe = 1,
+};
+/* *INDENT-ON* */
+
+punt_socket_detail_t *
+punt_socket_entries (u8 ipv)
+{
+  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)
+      {
+	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);
+	  }
+      }
+  }
+  return ps;
+}
+
+u8 *
+format_punt_socket (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;
+
+  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);
+	  }
+      }
+  }
+
+  return (s);
+}
+
+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;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "ipv4"))
+	is_ipv6 = 0;
+      else if (unformat (input, "ipv6"))
+	is_ipv6 = 1;
+      else
+	{
+	  error = clib_error_return (0, "parse error: '%U'",
+				     format_unformat_error, input);
+	  goto done;
+	}
+    }
+
+  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);
+
+done:
+  return (error);
+}
+
+/*?
+ *
+ * @cliexpar
+ * @cliexcmd{show punt socket ipv4}
+ ?*/
+/* *INDENT-OFF* */
+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]",
+  .is_mp_safe = 1,
+};
+/* *INDENT-ON* */
+
 clib_error_t *
 punt_init (vlib_main_t * vm)
 {
@@ -850,7 +1083,7 @@ punt_config (vlib_main_t * vm, unformat_input_t * input)
   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
     {
       if (unformat (input, "socket %s", &socket_path))
-	strncpy (pm->sun_path, socket_path, 108 - 1);
+	strncpy (pm->sun_path, socket_path, UNIX_PATH_MAX - 1);
       else
 	return clib_error_return (0, "unknown input `%U'",
 				  format_unformat_error, input);
diff --git a/src/vnet/ip/punt.h b/src/vnet/ip/punt.h
index 4cef5278558..0518b2b91ef 100644
--- a/src/vnet/ip/punt.h
+++ b/src/vnet/ip/punt.h
@@ -20,7 +20,7 @@
 #ifndef included_punt_h
 #define included_punt_h
 
-#include <sys/un.h>
+#include <linux/un.h>
 #include <stdbool.h>
 
 typedef enum
@@ -64,6 +64,7 @@ typedef struct __attribute__ ((packed))
  */
 typedef struct
 {
+  u8 protocol;
   u16 port;
   struct sockaddr_un caddr;
 } punt_client_t;
@@ -82,6 +83,15 @@ typedef struct
 } punt_main_t;
 extern punt_main_t punt_main;
 
+typedef struct punt_socket_detail_t_
+{
+  u8 ipv;
+  u8 l4_protocol;
+  u16 l4_port;
+  u8 pathname[108];
+} punt_socket_detail_t;
+
+punt_socket_detail_t *punt_socket_entries (u8 ipv);
 #endif
 
 /*
diff --git a/src/vnet/ip/punt_api.c b/src/vnet/ip/punt_api.c
index 55ab838b167..3ca9621a410 100644
--- a/src/vnet/ip/punt_api.c
+++ b/src/vnet/ip/punt_api.c
@@ -40,27 +40,35 @@
 #include <vlibapi/api_helper_macros.h>
 
 #define foreach_punt_api_msg                                            \
-_(PUNT, punt)                                                           \
+_(SET_PUNT, set_punt)                                                   \
 _(PUNT_SOCKET_REGISTER, punt_socket_register)                           \
-_(PUNT_SOCKET_DEREGISTER, punt_socket_deregister)
+_(PUNT_SOCKET_DEREGISTER, punt_socket_deregister)                       \
+_(PUNT_DUMP, punt_dump)                                                 \
+_(PUNT_SOCKET_DUMP, punt_socket_dump)
 
 static void
-vl_api_punt_t_handler (vl_api_punt_t * mp)
+vl_api_set_punt_t_handler (vl_api_set_punt_t * mp)
 {
-  vl_api_punt_reply_t *rmp;
+  vl_api_set_punt_reply_t *rmp;
   vlib_main_t *vm = vlib_get_main ();
   int rv = 0;
   clib_error_t *error;
 
-  error = vnet_punt_add_del (vm, mp->ipv, mp->l4_protocol,
-			     ntohs (mp->l4_port), mp->is_add);
+  error = vnet_punt_add_del (vm, mp->punt.ipv, mp->punt.l4_protocol,
+			     ntohs (mp->punt.l4_port), mp->is_add);
   if (error)
     {
       rv = -1;
       clib_error_report (error);
     }
 
-  REPLY_MACRO (VL_API_PUNT_REPLY);
+  REPLY_MACRO (VL_API_SET_PUNT_REPLY);
+}
+
+static void
+vl_api_punt_dump_t_handler (vl_api_punt_dump_t * mp)
+{
+
 }
 
 static void
@@ -72,9 +80,10 @@ vl_api_punt_socket_register_t_handler (vl_api_punt_socket_register_t * mp)
   clib_error_t *error;
   vl_api_registration_t *reg;
 
-  error = vnet_punt_socket_add (vm, ntohl (mp->header_version),
-				mp->is_ip4, mp->l4_protocol,
-				ntohs (mp->l4_port), (char *) mp->pathname);
+  error = 0;
+  vnet_punt_socket_add (vm, ntohl (mp->header_version),
+			mp->punt.ipv, mp->punt.l4_protocol,
+			ntohs (mp->punt.l4_port), (char *) mp->pathname);
   if (error)
     {
       rv = -1;
@@ -95,6 +104,48 @@ vl_api_punt_socket_register_t_handler (vl_api_punt_socket_register_t * mp)
   vl_api_send_msg (reg, (u8 *) rmp);
 }
 
+void
+send_punt_socket_details (vl_api_registration_t * reg,
+			  u32 context, punt_socket_detail_t * p)
+{
+  vl_api_punt_socket_details_t *mp;
+
+  mp = vl_msg_api_alloc (sizeof (*mp));
+  if (!mp)
+    return;
+
+  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));
+
+  vl_api_send_msg (reg, (u8 *) mp);
+}
+
+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;
+
+  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);
+}
+
 static void
 vl_api_punt_socket_deregister_t_handler (vl_api_punt_socket_deregister_t * mp)
 {
@@ -104,8 +155,8 @@ vl_api_punt_socket_deregister_t_handler (vl_api_punt_socket_deregister_t * mp)
   clib_error_t *error;
   vl_api_registration_t *reg;
 
-  error = vnet_punt_socket_del (vm, mp->is_ip4, mp->l4_protocol,
-				ntohs (mp->l4_port));
+  error = vnet_punt_socket_del (vm, mp->punt.ipv, mp->punt.l4_protocol,
+				ntohs (mp->punt.l4_port));
   if (error)
     {
       rv = -1;
diff --git a/src/vnet/sctp/sctp.c b/src/vnet/sctp/sctp.c
index 41548bc0d7a..85ca9b8048f 100644
--- a/src/vnet/sctp/sctp.c
+++ b/src/vnet/sctp/sctp.c
@@ -987,6 +987,29 @@ sctp_init (vlib_main_t * vm)
 
 VLIB_INIT_FUNCTION (sctp_init);
 
+static clib_error_t *
+show_sctp_punt_fn (vlib_main_t * vm, unformat_input_t * input,
+		   vlib_cli_command_t * cmd_arg)
+{
+  sctp_main_t *tm = &sctp_main;
+  if (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    return clib_error_return (0, "unknown input `%U'", format_unformat_error,
+			      input);
+  vlib_cli_output (vm, "IPv4 UDP punt: %s",
+		   tm->punt_unknown4 ? "enabled" : "disabled");
+  vlib_cli_output (vm, "IPv6 UDP punt: %s",
+		   tm->punt_unknown6 ? "enabled" : "disabled");
+  return 0;
+}
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (show_tcp_punt_command, static) =
+{
+  .path = "show sctp punt",
+  .short_help = "show sctp punt",
+  .function = show_sctp_punt_fn,
+};
+/* *INDENT-ON* */
+
 /*
  * fd.io coding-style-patch-verification: ON
  *
diff --git a/src/vnet/udp/udp.c b/src/vnet/udp/udp.c
index ccac921b8b3..8c2daaf66e6 100644
--- a/src/vnet/udp/udp.c
+++ b/src/vnet/udp/udp.c
@@ -441,6 +441,66 @@ udp_init (vlib_main_t * vm)
 
 VLIB_INIT_FUNCTION (udp_init);
 
+static clib_error_t *
+show_udp_punt_fn (vlib_main_t * vm, unformat_input_t * input,
+		  vlib_cli_command_t * cmd_arg)
+{
+  udp_main_t *um = vnet_get_udp_main ();
+
+  clib_error_t *error = NULL;
+
+  if (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    return clib_error_return (0, "unknown input `%U'", format_unformat_error,
+			      input);
+
+  udp_dst_port_info_t *port_info;
+  if (um->punt_unknown4)
+    {
+      vlib_cli_output (vm, "IPv4 UDP punt: enabled");
+    }
+  else
+    {
+      u8 *s = NULL;
+      vec_foreach (port_info, um->dst_port_infos[UDP_IP4])
+      {
+	if (udp_is_valid_dst_port (port_info->dst_port, 1))
+	  {
+	    s = format (s, (!s) ? "%d" : ", %d", port_info->dst_port);
+	  }
+      }
+      s = format (s, "%c", 0);
+      vlib_cli_output (vm, "IPV4 UDP ports punt : %s", s);
+    }
+
+  if (um->punt_unknown6)
+    {
+      vlib_cli_output (vm, "IPv6 UDP punt: enabled");
+    }
+  else
+    {
+      u8 *s = NULL;
+      vec_foreach (port_info, um->dst_port_infos[UDP_IP6])
+      {
+	if (udp_is_valid_dst_port (port_info->dst_port, 01))
+	  {
+	    s = format (s, (!s) ? "%d" : ", %d", port_info->dst_port);
+	  }
+      }
+      s = format (s, "%c", 0);
+      vlib_cli_output (vm, "IPV6 UDP ports punt : %s", s);
+    }
+
+  return (error);
+}
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (show_tcp_punt_command, static) =
+{
+  .path = "show udp punt",
+  .short_help = "show udp punt [ipv4|ipv6]",
+  .function = show_udp_punt_fn,
+};
+/* *INDENT-ON* */
+
 /*
  * fd.io coding-style-patch-verification: ON
  *
diff --git a/src/vnet/udp/udp.h b/src/vnet/udp/udp.h
index 8b94a0088f6..19db4f81777 100644
--- a/src/vnet/udp/udp.h
+++ b/src/vnet/udp/udp.h
@@ -252,6 +252,7 @@ void udp_register_dst_port (vlib_main_t * vm,
 			    u32 node_index, u8 is_ip4);
 void udp_unregister_dst_port (vlib_main_t * vm,
 			      udp_dst_port_t dst_port, u8 is_ip4);
+bool udp_is_valid_dst_port (udp_dst_port_t dst_port, u8 is_ip4);
 
 void udp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add);
 
diff --git a/src/vnet/udp/udp_local.c b/src/vnet/udp/udp_local.c
index bb7305d8d03..a16ba22cf27 100644
--- a/src/vnet/udp/udp_local.c
+++ b/src/vnet/udp/udp_local.c
@@ -549,6 +549,22 @@ udp_unregister_dst_port (vlib_main_t * vm, udp_dst_port_t dst_port, u8 is_ip4)
   n[0] = SPARSE_VEC_INVALID_INDEX;
 }
 
+bool
+udp_is_valid_dst_port (udp_dst_port_t dst_port, u8 is_ip4)
+{
+  udp_main_t *um = &udp_main;
+  u16 *n;
+
+  if (is_ip4)
+    n = sparse_vec_validate (um->next_by_dst_port4,
+			     clib_host_to_net_u16 (dst_port));
+  else
+    n = sparse_vec_validate (um->next_by_dst_port6,
+			     clib_host_to_net_u16 (dst_port));
+
+  return (n[0] != SPARSE_VEC_INVALID_INDEX);
+}
+
 void
 udp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add)
 {