VPP-395 Add udp-punt node(s) and API

Uses existing UDP local API in order to register
requested UDP port punt to the host.

CLI: set punt udp [del] <port>
API: punt protocol <l4-protocol> [ip <ver>] [port <l4-port>] [del]
* Only UDP (l4-protocol = 17) is supported at this time

Change-Id: I9232af1c891d1ed174d77f3e0dfe60c4b9d85e40
Signed-off-by: Alex Popovsky <apopovsk@cisco.com>

5 files changed, 379 insertions, 3 deletions

diff --git a/vnet/Makefile.am b/vnet/Makefile.am
index 1b7b96911f9..88d556404b7 100644
--- a/vnet/Makefile.am
+++ b/vnet/Makefile.am
@@ -290,6 +290,7 @@ libvnet_la_SOURCES +=				\
  vnet/ip/udp_format.c				\
  vnet/ip/udp_init.c				\
  vnet/ip/udp_local.c				\
+ vnet/ip/punt.c					\
  vnet/ip/udp_pg.c                               \
  vnet/ip/ip_input_acl.c                         \
  vnet/ip/ip_frag.c
@@ -319,7 +320,9 @@ nobase_include_HEADERS +=			\
  vnet/ip/tcp_packet.h				\
  vnet/ip/udp.h					\
  vnet/ip/udp_error.def				\
- vnet/ip/udp_packet.h
+ vnet/ip/udp_packet.h				\
+ vnet/ip/punt_error.def				\
+ vnet/ip/punt.h
 
 ########################################
 # Layer 3 protocol: IPSec
diff --git a/vnet/vnet/ip/punt.c b/vnet/vnet/ip/punt.c
new file mode 100644
index 00000000000..188d03a82cc
--- /dev/null
+++ b/vnet/vnet/ip/punt.c
@@ -0,0 +1,311 @@
+/*
+ * 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 togather 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 <vlib/vlib.h>
+#include <vnet/pg/pg.h>
+#include <vnet/ip/udp.h>
+#include <vnet/ip/punt.h>
+
+#define foreach_punt_next \
+  _ (PUNT, "error-punt")
+
+typedef enum
+{
+#define _(s,n) PUNT_NEXT_##s,
+  foreach_punt_next
+#undef _
+    PUNT_N_NEXT,
+} punt_next_t;
+
+vlib_node_registration_t udp4_punt_node;
+vlib_node_registration_t udp6_punt_node;
+
+/** @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, 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, 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
+*/
+static uword
+udp4_punt (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
+*/
+static uword
+udp6_punt (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) = {
+  .function = udp4_punt,
+  .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_NODE_FUNCTION_MULTIARCH (udp4_punt_node, udp4_punt)
+
+VLIB_REGISTER_NODE (udp6_punt_node) = {
+  .function = udp6_punt,
+  .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 _
+  },
+};
+
+VLIB_NODE_FUNCTION_MULTIARCH (udp6_punt_node, udp6_punt)
+/* *INDENT-ON* */
+
+/**
+ * @brief Request IP traffic punt to the local TCP/IP stack.
+ *
+ * @em Note
+ * - UDP is the only protocol supported in the current implementation
+ * - When requesting UDP punt port number(s) must be specified
+ * - All TCP traffic is currently punted to the host by default
+ *
+ * @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 protocol 8-bits L4 protocol value
+ *                 Only value of 17 (UDP) is currently supported
+ * @param port     16-bits L4 (TCP/IP) port number when applicable
+ *
+ * @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,
+		   int is_add)
+{
+  /* For now we only support adding specific UDP port punt */
+  {
+    if (!is_add)
+      return clib_error_return (0, "punt delete is not supported yet");
+
+    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, "TCP/UDP port must be specified");
+  }
+
+  if (ipv != (u8) ~ 0)
+    {
+      if (ipv == 4)
+	udp_register_dst_port (vm, port, udp4_punt_node.index, 1);
+      else if (ipv == 6)
+	udp_register_dst_port (vm, port, udp6_punt_node.index, 0);
+      else
+	return clib_error_return (0, "IP version must be 4 or 6, got %d",
+				  ipv);
+    }
+  else
+    {
+      udp_register_dst_port (vm, port, udp4_punt_node.index, 1);
+      udp_register_dst_port (vm, port, udp6_punt_node.index, 0);
+    }
+
+  return 0;
+
+}
+
+static clib_error_t *
+udp_punt_cli (vlib_main_t * vm,
+	      unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+  u32 udp_port;
+  int is_add = 1;
+  clib_error_t *error;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "del"))
+	is_add = 0;
+      else if (unformat (input, "%d", &udp_port))
+	{
+	  /* punt both IPv6 and IPv4 when used in CLI */
+	  error = vnet_punt_add_del (vm, ~0, IP_PROTOCOL_UDP,
+				     udp_port, is_add);
+	  if (error)
+	    clib_error_report (error);
+	}
+    }
+
+  return 0;
+}
+
+/*?
+ * The set of '<em>set punt</em>' commands allows specific IP traffic to
+ * be punted to the host TCP/IP stack
+ *
+ * @em Note
+ * - UDP is the only protocol supported in the current implementation
+ * - When requesting UDP punt port number(s) must be specified
+ * - All TCP traffic is currently punted to the host by default
+ *
+ * @cliexpar
+ * @parblock
+ * Example of how to request NTP traffic to be punted
+ * @cliexcmd{set punt udp 125}
+ *
+ * @endparblock
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (punt_udp_command, static) = {
+  .path = "set punt udp",
+  .short_help = "set punt udp [del] port-num1 [port-num2 ...]",
+  .function = udp_punt_cli,
+};
+/* *INDENT-ON* */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/vnet/vnet/ip/punt.h b/vnet/vnet/ip/punt.h
new file mode 100644
index 00000000000..09a9d4c55bf
--- /dev/null
+++ b/vnet/vnet/ip/punt.h
@@ -0,0 +1,43 @@
+/*
+ * 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 Definitions for punt infrastructure.
+ */
+#ifndef included_punt_h
+#define included_punt_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;
+
+
+clib_error_t *vnet_punt_add_del (vlib_main_t * vm, u8 ipv,
+				 u8 protocol, u16 port, int is_add);
+
+#endif /* included_punt_h */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/vnet/vnet/ip/punt_error.def b/vnet/vnet/ip/punt_error.def
new file mode 100644
index 00000000000..a76d7e7b817
--- /dev/null
+++ b/vnet/vnet/ip/punt_error.def
@@ -0,0 +1,19 @@
+/*
+ * punt_error.def: punt errors
+ *
+ * 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.
+ */
+
+punt_error (NONE, "no error")
+punt_error (UDP_PORT, "udp port punt")
diff --git a/vnet/vnet/ip/udp_error.def b/vnet/vnet/ip/udp_error.def
index 46e3bd9ef47..311d20684c5 100644
--- a/vnet/vnet/ip/udp_error.def
+++ b/vnet/vnet/ip/udp_error.def
@@ -1,7 +1,7 @@
 /*
- * udp_error.def: gre errors
+ * udp_error.def: udp errors
  *
- * Copyright (c) 2013 Cisco and/or its affiliates.
+ * Copyright (c) 2013-2016 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: