SRv6 static proxy plugin

Change-Id: Ia0654461d9fa36503323a8375997719c873d23b9
Signed-off-by: Francois Clad <fclad@cisco.com>

8 files changed, 1272 insertions, 0 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index 4db3f9d3537..81b34f896c0 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -155,6 +155,11 @@ M:  Hongjun Ni <hongjun.ni@intel.com>
 F:  src/plugins/pppoe/
 F:  src/plugins/pppoe.am
 
+Plugin - IPv6 Segment Routing Static Proxy
+M:	Francois Clad <fclad@cisco.com>
+F:	src/plugins/srv6-as/
+F:	src/plugins/srv6_as.am
+
 Test Infrastructure
 M:	Klement Sekera <ksekera@cisco.com>
 F:	test/
diff --git a/src/configure.ac b/src/configure.ac
index bfd59372084..d28b6c1ccfd 100644
--- a/src/configure.ac
+++ b/src/configure.ac
@@ -221,6 +221,7 @@ PLUGIN_ENABLED(marvell)
 PLUGIN_ENABLED(memif)
 PLUGIN_ENABLED(pppoe)
 PLUGIN_ENABLED(sixrd)
+PLUGIN_ENABLED(srv6as)
 PLUGIN_ENABLED(nat)
 PLUGIN_ENABLED(stn)
 PLUGIN_ENABLED(l2e)
diff --git a/src/plugins/Makefile.am b/src/plugins/Makefile.am
index 5e54d0e504a..1e3f8764218 100644
--- a/src/plugins/Makefile.am
+++ b/src/plugins/Makefile.am
@@ -83,6 +83,10 @@ if ENABLE_SIXRD_PLUGIN
 include sixrd.am
 endif
 
+if ENABLE_SRV6AS_PLUGIN
+include srv6_as.am
+endif
+
 if ENABLE_NAT_PLUGIN
 include nat.am
 endif
diff --git a/src/plugins/srv6-as/as.c b/src/plugins/srv6-as/as.c
new file mode 100644
index 00000000000..d027656b6fc
--- /dev/null
+++ b/src/plugins/srv6-as/as.c
@@ -0,0 +1,502 @@
+/*
+ * Copyright (c) 2015 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.
+ */
+/*
+ *------------------------------------------------------------------
+ * as.c - SRv6 Static Proxy (AS) function
+ *------------------------------------------------------------------
+ */
+
+#include <vnet/vnet.h>
+#include <vnet/adj/adj.h>
+#include <vnet/plugin/plugin.h>
+#include <srv6-as/as.h>
+
+#define SID_CREATE_IFACE_FEATURE_ERROR  -1
+#define SID_CREATE_INVALID_IFACE_TYPE   -3
+#define SID_CREATE_INVALID_IFACE_INDEX  -4
+#define SID_CREATE_INVALID_ADJ_INDEX    -5
+
+unsigned char function_name[] = "SRv6-AS-plugin";
+unsigned char keyword_str[] = "End.AS";
+unsigned char def_str[] =
+  "Endpoint with static proxy to SR-unaware appliance";
+unsigned char params_str[] =
+  "nh <next-hop> oif <iface-out> iif <iface-in> src <src-addr> next <sid> [next <sid> ...]";
+
+
+static inline u8 *
+prepare_rewrite (ip6_address_t src_addr, ip6_address_t * sid_list,
+		 u8 protocol)
+{
+  u8 *rewrite_str = NULL;
+  u32 rewrite_len = IPv6_DEFAULT_HEADER_LENGTH;
+
+  u8 num_sids = vec_len (sid_list);
+  u32 sr_hdr_len = 0;
+
+  if (num_sids > 1)
+    {
+      sr_hdr_len =
+	sizeof (ip6_sr_header_t) + num_sids * sizeof (ip6_address_t);
+      rewrite_len += sr_hdr_len;
+    }
+
+  vec_validate (rewrite_str, rewrite_len - 1);
+
+  /* Fill IP header */
+  ip6_header_t *iph = (ip6_header_t *) rewrite_str;
+  iph->ip_version_traffic_class_and_flow_label =
+    clib_host_to_net_u32 (0 | ((6 & 0xF) << 28));
+  iph->src_address = src_addr;
+  iph->dst_address = sid_list[0];
+  iph->payload_length = sr_hdr_len;
+  iph->hop_limit = IPv6_DEFAULT_HOP_LIMIT;
+
+  if (num_sids > 1)
+    {
+      /* Set Next Header value to Routing Extension */
+      iph->protocol = IP_PROTOCOL_IPV6_ROUTE;
+
+      /* Fill SR header */
+      ip6_sr_header_t *srh = (ip6_sr_header_t *) (iph + 1);
+      srh->protocol = protocol;
+      srh->length = sr_hdr_len / 8 - 1;
+      srh->type = ROUTING_HEADER_TYPE_SR;
+      srh->segments_left = num_sids - 1;
+      srh->first_segment = num_sids - 1;
+      srh->flags = 0x00;
+      srh->reserved = 0x00;
+
+      /* Fill segment list */
+      ip6_address_t *this_address;
+      ip6_address_t *addrp = srh->segments + srh->first_segment;
+      vec_foreach (this_address, sid_list)
+      {
+	*addrp = *this_address;
+	addrp--;
+      }
+    }
+  else
+    {
+      /* Set Next Header value to inner protocol */
+      iph->protocol = protocol;
+    }
+
+  return rewrite_str;
+}
+
+static inline void
+free_ls_mem (srv6_as_localsid_t * ls_mem)
+{
+  vec_free (ls_mem->rewrite);
+  vec_free (ls_mem->sid_list);
+  clib_mem_free (ls_mem);
+}
+
+
+/*****************************************/
+/* SRv6 LocalSID instantiation and removal functions */
+static int
+srv6_as_localsid_creation_fn (ip6_sr_localsid_t * localsid)
+{
+  ip6_sr_main_t *srm = &sr_main;
+  srv6_as_main_t *sm = &srv6_as_main;
+  srv6_as_localsid_t *ls_mem = localsid->plugin_mem;
+  u32 localsid_index = localsid - srm->localsids;
+
+  /* Step 1: Prepare xconnect adjacency for sending packets to the VNF */
+
+  /* Retrieve the adjacency corresponding to the (OIF, next_hop) */
+  adj_index_t nh_adj_index = ADJ_INDEX_INVALID;
+  if (ls_mem->ip_version == DA_IP4)
+    nh_adj_index = adj_nbr_add_or_lock (FIB_PROTOCOL_IP4,
+					VNET_LINK_IP4, &ls_mem->nh_addr,
+					ls_mem->sw_if_index_out);
+  else if (ls_mem->ip_version == DA_IP6)
+    nh_adj_index = adj_nbr_add_or_lock (FIB_PROTOCOL_IP6,
+					VNET_LINK_IP6, &ls_mem->nh_addr,
+					ls_mem->sw_if_index_out);
+  if (nh_adj_index == ADJ_INDEX_INVALID)
+    {
+      free_ls_mem (ls_mem);
+      return SID_CREATE_INVALID_ADJ_INDEX;
+    }
+
+  ls_mem->nh_adj = nh_adj_index;
+
+
+  /* Step 2: Prepare inbound policy for packets returning from the VNF */
+
+  /* Make sure the provided incoming interface index is valid */
+  if (pool_is_free_index (sm->vnet_main->interface_main.sw_interfaces,
+			  ls_mem->sw_if_index_in))
+    {
+      adj_unlock (ls_mem->nh_adj);
+      free_ls_mem (ls_mem);
+      return SID_CREATE_INVALID_IFACE_INDEX;
+    }
+
+  /* Retrieve associated interface structure */
+  vnet_sw_interface_t *sw = vnet_get_sw_interface (sm->vnet_main,
+						   ls_mem->sw_if_index_in);
+  if (sw->type != VNET_SW_INTERFACE_TYPE_HARDWARE)
+    {
+      adj_unlock (ls_mem->nh_adj);
+      free_ls_mem (ls_mem);
+      return SID_CREATE_INVALID_IFACE_TYPE;
+    }
+
+  if (ls_mem->ip_version == DA_IP4)
+    {
+      /* Enable End.AS4 rewrite node for this interface */
+      int ret =
+	vnet_feature_enable_disable ("ip4-unicast", "srv6-as4-rewrite",
+				     ls_mem->sw_if_index_in, 1, 0, 0);
+      if (ret != 0)
+	{
+	  adj_unlock (ls_mem->nh_adj);
+	  free_ls_mem (ls_mem);
+	  return SID_CREATE_IFACE_FEATURE_ERROR;
+	}
+
+      /* Prepare rewrite string */
+      ls_mem->rewrite = prepare_rewrite (ls_mem->src_addr, ls_mem->sid_list,
+					 IP_PROTOCOL_IP_IN_IP);
+
+      /* Associate local SID index to this interface (resize vector if needed) */
+      if (ls_mem->sw_if_index_in >= vec_len (sm->sw_iface_localsid4))
+	{
+	  vec_resize (sm->sw_iface_localsid4,
+		      (pool_len (sm->vnet_main->interface_main.sw_interfaces)
+		       - vec_len (sm->sw_iface_localsid4)));
+	}
+      sm->sw_iface_localsid4[ls_mem->sw_if_index_in] = localsid_index;
+    }
+  else if (ls_mem->ip_version == DA_IP6)
+    {
+      /* Enable End.AS6 rewrite node for this interface */
+      int ret =
+	vnet_feature_enable_disable ("ip6-unicast", "srv6-as6-rewrite",
+				     ls_mem->sw_if_index_in, 1, 0, 0);
+      if (ret != 0)
+	{
+	  adj_unlock (ls_mem->nh_adj);
+	  free_ls_mem (ls_mem);
+	  return SID_CREATE_IFACE_FEATURE_ERROR;
+	}
+
+      /* Prepare rewrite string */
+      ls_mem->rewrite = prepare_rewrite (ls_mem->src_addr, ls_mem->sid_list,
+					 IP_PROTOCOL_IPV6);
+
+      /* Associate local SID index to this interface (resize vector if needed) */
+      if (ls_mem->sw_if_index_in >= vec_len (sm->sw_iface_localsid6))
+	{
+	  vec_resize (sm->sw_iface_localsid6,
+		      (pool_len (sm->vnet_main->interface_main.sw_interfaces)
+		       - vec_len (sm->sw_iface_localsid6)));
+	}
+      sm->sw_iface_localsid6[ls_mem->sw_if_index_in] = localsid_index;
+    }
+
+  return 0;
+}
+
+static int
+srv6_as_localsid_removal_fn (ip6_sr_localsid_t * localsid)
+{
+  srv6_as_main_t *sm = &srv6_as_main;
+  srv6_as_localsid_t *ls_mem = localsid->plugin_mem;
+
+  if (ls_mem->ip_version == DA_IP4)
+    {
+      /* Disable End.AS4 rewrite node for this interface */
+      int ret;
+      ret = vnet_feature_enable_disable ("ip4-unicast", "srv6-as4-rewrite",
+					 ls_mem->sw_if_index_in, 0, 0, 0);
+      if (ret != 0)
+	return -1;
+
+      /* Remove local SID index from interface table */
+      sm->sw_iface_localsid4[ls_mem->sw_if_index_in] = ~(u32) 0;
+    }
+  else if (ls_mem->ip_version == DA_IP6)
+    {
+      /* Disable End.AS6 rewrite node for this interface */
+      int ret;
+      ret = vnet_feature_enable_disable ("ip6-unicast", "srv6-as6-rewrite",
+					 ls_mem->sw_if_index_in, 0, 0, 0);
+      if (ret != 0)
+	return -1;
+
+      /* Remove local SID index from interface table */
+      sm->sw_iface_localsid6[ls_mem->sw_if_index_in] = ~(u32) 0;
+    }
+
+
+  /* Unlock (OIF, NHOP) adjacency (from sr_localsid.c:103) */
+  adj_unlock (ls_mem->nh_adj);
+
+  /* Clean up local SID memory */
+  free_ls_mem (ls_mem);
+
+  return 0;
+}
+
+/**********************************/
+/* SRv6 LocalSID format functions */
+/*
+ * Prints nicely the parameters of a localsid
+ * Example: print "Table 5"
+ */
+u8 *
+format_srv6_as_localsid (u8 * s, va_list * args)
+{
+  srv6_as_localsid_t *ls_mem = va_arg (*args, void *);
+
+  vnet_main_t *vnm = vnet_get_main ();
+
+  if (ls_mem->ip_version == DA_IP4)
+    {
+      s =
+	format (s, "Next-hop:\t%U\n", format_ip4_address,
+		&ls_mem->nh_addr.ip4);
+    }
+  else
+    {
+      s =
+	format (s, "Next-hop:\t%U\n", format_ip6_address,
+		&ls_mem->nh_addr.ip6);
+    }
+
+  s = format (s, "\tOutgoing iface:\t%U\n", format_vnet_sw_if_index_name, vnm,
+	      ls_mem->sw_if_index_out);
+  s = format (s, "\tIncoming iface:\t%U\n", format_vnet_sw_if_index_name, vnm,
+	      ls_mem->sw_if_index_in);
+  s = format (s, "\tSource address:\t%U\n", format_ip6_address,
+	      &ls_mem->src_addr);
+
+  s = format (s, "\tSegment list:\t< ");
+  ip6_address_t *addr;
+  vec_foreach (addr, ls_mem->sid_list)
+  {
+    s = format (s, "%U, ", format_ip6_address, addr);
+  }
+  s = format (s, "\b\b > ");
+
+  return s;
+}
+
+/*
+ * Process the parameters of a localsid
+ * Example: process from:
+ * sr localsid address cafe::1 behavior new_srv6_localsid 5
+ * everything from behavior on... so in this case 'new_srv6_localsid 5'
+ * Notice that it MUST match the keyword_str and params_str defined above.
+ */
+uword
+unformat_srv6_as_localsid (unformat_input_t * input, va_list * args)
+{
+  void **plugin_mem_p = va_arg (*args, void **);
+  srv6_as_localsid_t *ls_mem;
+
+  vnet_main_t *vnm = vnet_get_main ();
+
+  u8 ip_version = 0;
+  ip46_address_t nh_addr;
+  u32 sw_if_index_out;
+  u32 sw_if_index_in;
+  ip6_address_t src_addr;
+  ip6_address_t next_sid;
+  ip6_address_t *sid_list = NULL;
+
+  u8 params = 0;
+#define PARAM_AS_NH   (1 << 0)
+#define PARAM_AS_OIF  (1 << 1)
+#define PARAM_AS_IIF  (1 << 2)
+#define PARAM_AS_SRC  (1 << 3)
+
+  if (!unformat (input, "end.as"))
+    return 0;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (!(params & PARAM_AS_NH) && unformat (input, "nh %U",
+					       unformat_ip4_address,
+					       &nh_addr.ip4))
+	{
+	  ip_version = DA_IP4;
+	  params |= PARAM_AS_NH;
+	}
+      if (!(params & PARAM_AS_NH) && unformat (input, "nh %U",
+					       unformat_ip6_address,
+					       &nh_addr.ip6))
+	{
+	  ip_version = DA_IP6;
+	  params |= PARAM_AS_NH;
+	}
+      else if (!(params & PARAM_AS_OIF) && unformat (input, "oif %U",
+						     unformat_vnet_sw_interface,
+						     vnm, &sw_if_index_out))
+	{
+	  params |= PARAM_AS_OIF;
+	}
+      else if (!(params & PARAM_AS_IIF) && unformat (input, "iif %U",
+						     unformat_vnet_sw_interface,
+						     vnm, &sw_if_index_in))
+	{
+	  params |= PARAM_AS_IIF;
+	}
+      else if (!(params & PARAM_AS_SRC) && unformat (input, "src %U",
+						     unformat_ip6_address,
+						     &src_addr))
+	{
+	  params |= PARAM_AS_SRC;
+	}
+      else if (unformat (input, "next %U", unformat_ip6_address, &next_sid))
+	{
+	  vec_add1 (sid_list, next_sid);
+	}
+      else
+	{
+	  break;
+	}
+    }
+
+  /* Make sure that all parameters are supplied */
+  u8 params_chk = (PARAM_AS_NH | PARAM_AS_OIF | PARAM_AS_IIF | PARAM_AS_SRC);
+  if ((params & params_chk) != params_chk || sid_list == NULL)
+    {
+      vec_free (sid_list);
+      return 0;
+    }
+
+  /* Allocate and initialize memory block for local SID parameters */
+  ls_mem = clib_mem_alloc_aligned_at_offset (sizeof *ls_mem, 0, 0, 1);
+  memset (ls_mem, 0, sizeof *ls_mem);
+  *plugin_mem_p = ls_mem;
+
+  /* Set local SID parameters */
+  ls_mem->ip_version = ip_version;
+  if (ip_version == DA_IP4)
+    ls_mem->nh_addr.ip4 = nh_addr.ip4;
+  else
+    ls_mem->nh_addr.ip6 = nh_addr.ip6;
+  ls_mem->sw_if_index_out = sw_if_index_out;
+  ls_mem->sw_if_index_in = sw_if_index_in;
+  ls_mem->src_addr = src_addr;
+  ls_mem->sid_list = sid_list;
+
+  return 1;
+}
+
+/*************************/
+/* SRv6 LocalSID FIB DPO */
+static u8 *
+format_srv6_as_dpo (u8 * s, va_list * args)
+{
+  index_t index = va_arg (*args, index_t);
+  CLIB_UNUSED (u32 indent) = va_arg (*args, u32);
+
+  return (format (s, "SR: static_proxy_index:[%u]", index));
+}
+
+void
+srv6_as_dpo_lock (dpo_id_t * dpo)
+{
+}
+
+void
+srv6_as_dpo_unlock (dpo_id_t * dpo)
+{
+}
+
+const static dpo_vft_t srv6_as_vft = {
+  .dv_lock = srv6_as_dpo_lock,
+  .dv_unlock = srv6_as_dpo_unlock,
+  .dv_format = format_srv6_as_dpo,
+};
+
+const static char *const srv6_as_ip6_nodes[] = {
+  "srv6-as-localsid",
+  NULL,
+};
+
+const static char *const *const srv6_as_nodes[DPO_PROTO_NUM] = {
+  [DPO_PROTO_IP6] = srv6_as_ip6_nodes,
+};
+
+/**********************/
+static clib_error_t *
+srv6_as_init (vlib_main_t * vm)
+{
+  srv6_as_main_t *sm = &srv6_as_main;
+  int rv = 0;
+
+  sm->vlib_main = vm;
+  sm->vnet_main = vnet_get_main ();
+
+  /* Create DPO */
+  sm->srv6_as_dpo_type = dpo_register_new_type (&srv6_as_vft, srv6_as_nodes);
+
+  /* Register SRv6 LocalSID */
+  rv = sr_localsid_register_function (vm,
+				      function_name,
+				      keyword_str,
+				      def_str,
+				      params_str,
+				      &sm->srv6_as_dpo_type,
+				      format_srv6_as_localsid,
+				      unformat_srv6_as_localsid,
+				      srv6_as_localsid_creation_fn,
+				      srv6_as_localsid_removal_fn);
+  if (rv < 0)
+    clib_error_return (0, "SRv6 LocalSID function could not be registered.");
+  else
+    sm->srv6_localsid_behavior_id = rv;
+
+  return 0;
+}
+
+/* *INDENT-OFF* */
+VNET_FEATURE_INIT (srv6_as4_rewrite, static) =
+{
+  .arc_name = "ip4-unicast",
+  .node_name = "srv6-as4-rewrite",
+  .runs_before = 0,
+};
+
+VNET_FEATURE_INIT (srv6_as6_rewrite, static) =
+{
+  .arc_name = "ip6-unicast",
+  .node_name = "srv6-as6-rewrite",
+  .runs_before = 0,
+};
+
+VLIB_INIT_FUNCTION (srv6_as_init);
+
+VLIB_PLUGIN_REGISTER () = {
+  .version = "1.0",
+  .description = "Static SRv6 proxy",
+};
+/* *INDENT-ON* */
+
+/*
+* fd.io coding-style-patch-verification: ON
+*
+* Local Variables:
+* eval: (c-set-style "gnu")
+* End:
+*/
diff --git a/src/plugins/srv6-as/as.h b/src/plugins/srv6-as/as.h
new file mode 100644
index 00000000000..8f059187151
--- /dev/null
+++ b/src/plugins/srv6-as/as.h
@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2015 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.
+ */
+#ifndef __included_srv6_as_h__
+#define __included_srv6_as_h__
+
+#include <vnet/vnet.h>
+#include <vnet/ip/ip.h>
+#include <vnet/srv6/sr.h>
+#include <vnet/srv6/sr_packet.h>
+
+#include <vppinfra/error.h>
+#include <vppinfra/elog.h>
+
+#define DA_IP4 4
+#define DA_IP6 6
+
+typedef struct
+{
+  u16 msg_id_base;			/**< API message ID base */
+
+  vlib_main_t *vlib_main;		/**< [convenience] vlib main */
+  vnet_main_t *vnet_main;		/**< [convenience] vnet main */
+
+  dpo_type_t srv6_as_dpo_type;		/**< DPO type */
+
+  u32 srv6_localsid_behavior_id;	/**< SRv6 LocalSID behavior number */
+
+  u32 *sw_iface_localsid4;		/**< Retrieve local SID from iface */
+  u32 *sw_iface_localsid6;		/**< Retrieve local SID from iface */
+} srv6_as_main_t;
+
+/*
+ * This is the memory that will be stored per each localsid
+ * the user instantiates
+ */
+typedef struct
+{
+  ip46_address_t nh_addr;		/**< Proxied device address */
+  u32 sw_if_index_out;			/**< Outgoing iface to proxied dev. */
+  u32 nh_adj;				/**< Adjacency index for out. iface */
+  u8 ip_version;
+
+  u32 sw_if_index_in;			/**< Incoming iface from proxied dev. */
+  u8 *rewrite;				/**< Headers to be rewritten */
+  ip6_address_t src_addr;		/**< Source address to be restored */
+  ip6_address_t *sid_list;		/**< SID list to be restored */
+  char *sid_list_str;
+} srv6_as_localsid_t;
+
+srv6_as_main_t srv6_as_main;
+
+format_function_t format_srv6_as_localsid;
+unformat_function_t unformat_srv6_as_localsid;
+
+void srv6_as_dpo_lock (dpo_id_t * dpo);
+void srv6_as_dpo_unlock (dpo_id_t * dpo);
+
+extern vlib_node_registration_t srv6_as_localsid_node;
+
+#endif /* __included_srv6_as_h__ */
+
+/*
+* fd.io coding-style-patch-verification: ON
+*
+* Local Variables:
+* eval: (c-set-style "gnu")
+* End:
+*/
diff --git a/src/plugins/srv6-as/as_plugin_doc.md b/src/plugins/srv6-as/as_plugin_doc.md
new file mode 100644
index 00000000000..d8a39496a3d
--- /dev/null
+++ b/src/plugins/srv6-as/as_plugin_doc.md
@@ -0,0 +1,165 @@
+# SRv6 endpoint to SR-unaware appliance via static proxy (End.AS) {#srv6_as_plugin_doc}
+
+## Overview
+
+The static proxy is an SR endpoint behavior for processing SR-MPLS or SRv6
+encapsulated traffic on behalf of an SR-unaware service.  This proxy thus
+receives SR traffic that is formed of an MPLS label stack or an IPv6 header on
+top of an inner packet, which can be Ethernet, IPv4 or IPv6.
+
+A static SR proxy segment is associated with the following mandatory parameters:
+
+- INNER-TYPE: Inner packet type
+- S-ADDR: Ethernet or IP address of the service (only for inner type IPv4 and
+	IPv6)
+- IFACE-OUT: Local interface for sending traffic towards the service
+- IFACE-IN: Local interface receiving the traffic coming back from the service
+- CACHE: SR information to be attached on the traffic coming back from the
+	service
+
+A static SR proxy segment is thus defined for a specific service, inner packet
+type and cached SR information.  It is also bound to a pair of directed
+interfaces on the proxy.  These may be both directions of a single interface, or
+opposite directions of two different interfaces.  The latter is recommended in
+case the service is to be used as part of a bi-directional SR SC policy.  If the
+proxy and the service both support 802.1Q, IFACE-OUT and IFACE-IN can also
+represent sub-interfaces.
+
+The first part of this behavior is triggered when the proxy node receives a
+packet whose active segment matches a segment associated with the static proxy
+behavior.  It removes the SR information from the packet then sends it on a
+specific interface towards the associated service.  This SR information
+corresponds to the full label stack for SR-MPLS or to the encapsulation IPv6
+header with any attached extension header in the case of SRv6.
+
+The second part is an inbound policy attached to the proxy interface receiving
+the traffic returning from the service, IFACE-IN.  This policy attaches to the
+incoming traffic the cached SR information associated with the SR proxy segment.
+If the proxy segment uses the SR-MPLS data plane, CACHE contains a stack of
+labels to be pushed on top the packets.  With the SRv6 data plane, CACHE is
+defined as a source address, an active segment and an optional SRH (tag,
+segments left, segment list and metadata).  The proxy encapsulates the packets
+with an IPv6 header that has the source address, the active segment as
+destination address and the SRH as a routing extension header.  After the SR
+information has been attached, the packets are forwarded according to the active
+segment, which is represented by the top MPLS label or the IPv6 Destination
+Address.
+
+In this scenario, there are no restrictions on the operations that can be
+performed by the service on the stream of packets.  It may operate at all
+protocol layers, terminate transport layer connections, generate new packets and
+initiate transport layer connections.  This behavior may also be used to
+integrate an IPv4-only service into an SRv6 policy.  However, a static SR proxy
+segment can be used in only one service chain at a time.  As opposed to most
+other segment types, a static SR proxy segment is bound to a unique list of
+segments, which represents a directed SR SC policy.  This is due to the cached
+SR information being defined in the segment configuration.  This limitation only
+prevents multiple segment lists from using the same static SR proxy segment at
+the same time, but a single segment list can be shared by any number of traffic
+flows.  Besides, since the returning traffic from the service is re- classified
+based on the incoming interface, an interface can be used as receiving interface
+(IFACE-IN) only for a single SR proxy segment at a time.  In the case of a
+bi-directional SR SC policy, a different SR proxy segment and receiving
+interface are required for the return direction.
+
+## SRv6 pseudocode
+
+### Static proxy for inner type Ethernet - End.AS2
+
+Upon receiving an IPv6 packet destined for S, where S is an End.AS2 SID, a node
+N does:
+
+```
+   1.   IF ENH == 59 THEN                                        ;; Ref1
+   2.       Remove the (outer) IPv6 header and its extension headers
+   3.       Forward the exposed frame on IFACE-OUT
+   4.   ELSE
+   5.       Drop the packet
+```
+
+Ref1: 59 refers to "no next header" as defined by IANA allocation for Internet
+Protocol Numbers.
+
+Upon receiving on IFACE-IN an Ethernet frame with a destination address
+different than the interface address, a node N does:
+
+```
+   1.   IF CACHE.SRH THEN                                        ;; Ref2
+   2.       Push CACHE.SRH on top of the existing Ethernet header
+   3.       Set NH value of the pushed SRH to 59
+   4.   Push outer IPv6 header with SA, DA and traffic class from CACHE
+   5.   Set outer payload length and flow label
+   6.   Set NH value to 43 if an SRH was added, or 59 otherwise
+   7.   Lookup outer DA in appropriate table and proceed accordingly
+```
+
+Ref2: CACHE.SRH represents the SRH defined in CACHE, if any, for the static SR
+proxy segment associated with IFACE-IN.
+
+The receiving interface must be configured in promiscuous mode in order to
+accept those Ethernet frames.
+
+### Static proxy for inner type IPv4 - End.AS4
+
+Upon receiving an IPv6 packet destined for S, where S is an End.AS4 SID, a node
+N does:
+
+```
+   1.   IF ENH == 4 THEN                                         ;; Ref1
+   2.       Remove the (outer) IPv6 header and its extension headers
+   3.       Forward the exposed packet on IFACE-OUT towards S-ADDR
+   4.   ELSE
+   5.       Drop the packet
+```
+
+Ref1: 4 refers to IPv4 encapsulation as defined by IANA allocation for Internet
+Protocol Numbers.
+
+Upon receiving a non link-local IPv4 packet on IFACE-IN, a node N does:
+
+```
+   1.   IF CACHE.SRH THEN                                        ;; Ref2
+   2.       Push CACHE.SRH on top of the existing IPv4 header
+   3.       Set NH value of the pushed SRH to 4
+   4.   Push outer IPv6 header with SA, DA and traffic class from CACHE
+   5.   Set outer payload length and flow label
+   6.   Set NH value to 43 if an SRH was added, or 4 otherwise
+   7.   Decrement inner TTL and update checksum
+   8.   Lookup outer DA in appropriate table and proceed accordingly
+```
+
+Ref2: CACHE.SRH represents the SRH defined in CACHE, if any, for the static SR
+proxy segment associated with IFACE-IN.
+
+### Static proxy for inner type IPv6 - End.AS6
+
+Upon receiving an IPv6 packet destined for S, where S is an End.AS6 SID, a node
+N does:
+
+```
+   1.   IF ENH == 41 THEN                                        ;; Ref1
+   2.       Remove the (outer) IPv6 header and its extension headers
+   3.       Forward the exposed packet on IFACE-OUT towards S-ADDR
+   4.   ELSE
+   5.       Drop the packet
+```
+
+Ref1: 41 refers to IPv6 encapsulation as defined by IANA allocation for Internet
+Protocol Numbers.
+
+Upon receiving a non-link-local IPv6 packet on IFACE-IN, a node N does:
+
+```
+   1.   IF CACHE.SRH THEN                                        ;; Ref2
+   2.       Push CACHE.SRH on top of the existing IPv6 header
+   3.       Set NH value of the pushed SRH to 41
+   4.   Push outer IPv6 header with SA, DA and traffic class from CACHE
+   5.   Set outer payload length and flow label
+   6.   Set NH value to 43 if an SRH was added, or 41 otherwise
+   7.   Decrement inner Hop Limit
+   8.   Lookup outer DA in appropriate table and proceed accordingly
+```
+
+Ref2: CACHE.SRH represents the SRH defined in CACHE, if any, for the static SR
+proxy segment associated with IFACE-IN.
+
diff --git a/src/plugins/srv6-as/node.c b/src/plugins/srv6-as/node.c
new file mode 100644
index 00000000000..921799fb7a5
--- /dev/null
+++ b/src/plugins/srv6-as/node.c
@@ -0,0 +1,492 @@
+/*
+ * Copyright (c) 2015 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.
+ */
+#include <vlib/vlib.h>
+#include <vnet/vnet.h>
+#include <vppinfra/error.h>
+#include <srv6-as/as.h>
+
+
+/******************************* Packet tracing *******************************/
+
+typedef struct
+{
+  u32 localsid_index;
+} srv6_as_localsid_trace_t;
+
+typedef struct
+{
+  ip6_address_t src, dst;
+} srv6_as_rewrite_trace_t;
+
+static u8 *
+format_srv6_as_localsid_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 *);
+  srv6_as_localsid_trace_t *t = va_arg (*args, srv6_as_localsid_trace_t *);
+
+  return format (s, "SRv6-AS-localsid: localsid_index %d", t->localsid_index);
+}
+
+static u8 *
+format_srv6_as_rewrite_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 *);
+  srv6_as_rewrite_trace_t *t = va_arg (*args, srv6_as_rewrite_trace_t *);
+
+  return format (s, "SRv6-AS-rewrite: src %U dst %U",
+		 format_ip6_address, &t->src, format_ip6_address, &t->dst);
+}
+
+
+/***************************** Nodes registration *****************************/
+
+vlib_node_registration_t srv6_as4_rewrite_node;
+vlib_node_registration_t srv6_as6_rewrite_node;
+
+
+/****************************** Packet counters *******************************/
+
+#define foreach_srv6_as_rewrite_counter \
+_(PROCESSED, "srv6-as rewritten packets") \
+_(NO_RW, "(Error) No header for rewriting.")
+
+typedef enum
+{
+#define _(sym,str) SRV6_AS_REWRITE_COUNTER_##sym,
+  foreach_srv6_as_rewrite_counter
+#undef _
+    SRV6_AS_REWRITE_N_COUNTERS,
+} srv6_as_rewrite_counters;
+
+static char *srv6_as_rewrite_counter_strings[] = {
+#define _(sym,string) string,
+  foreach_srv6_as_rewrite_counter
+#undef _
+};
+
+
+/********************************* Next nodes *********************************/
+
+typedef enum
+{
+  SRV6_AS_LOCALSID_NEXT_ERROR,
+  SRV6_AS_LOCALSID_NEXT_REWRITE4,
+  SRV6_AS_LOCALSID_NEXT_REWRITE6,
+  SRV6_AS_LOCALSID_N_NEXT,
+} srv6_as_localsid_next_t;
+
+typedef enum
+{
+  SRV6_AS_REWRITE_NEXT_ERROR,
+  SRV6_AS_REWRITE_NEXT_LOOKUP,
+  SRV6_AS_REWRITE_N_NEXT,
+} srv6_as_rewrite_next_t;
+
+
+/******************************* Local SID node *******************************/
+
+/**
+ * @brief Function doing SRH processing for AS behavior
+ */
+static_always_inline void
+end_as_processing (vlib_buffer_t * b0,
+		   ip6_header_t * ip0,
+		   srv6_as_localsid_t * ls0_mem, u32 * next0)
+{
+  u16 encap_len;
+  ip6_ext_header_t *ext_hdr;
+  u8 hdr_type;
+
+  /* Compute encapsulation headers length */
+  encap_len = sizeof (ip6_header_t);
+  ext_hdr = (ip6_ext_header_t *) (ip0 + 1);
+  hdr_type = ip0->protocol;
+
+  while (ip6_ext_hdr (hdr_type))
+    {
+      encap_len += ip6_ext_header_len (ext_hdr);
+      hdr_type = ext_hdr->next_hdr;
+      ext_hdr = ip6_ext_next_header (ext_hdr);
+    }
+
+  /* Make sure next header is IP */
+  if (PREDICT_FALSE (hdr_type != IP_PROTOCOL_IPV6 &&
+		     hdr_type != IP_PROTOCOL_IP_IN_IP))
+    {
+      return;
+    }
+
+  /* Remove IP header and extensions */
+  vlib_buffer_advance (b0, encap_len);
+
+  /* Set Xconnect adjacency to VNF */
+  vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ls0_mem->nh_adj;
+
+  if (ls0_mem->ip_version == DA_IP4)
+    *next0 = SRV6_AS_LOCALSID_NEXT_REWRITE4;
+  else if (ls0_mem->ip_version == DA_IP6)
+    *next0 = SRV6_AS_LOCALSID_NEXT_REWRITE6;
+}
+
+/**
+ * @brief SRv6 AS Localsid graph node
+ */
+static uword
+srv6_as_localsid_fn (vlib_main_t * vm,
+		     vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  ip6_sr_main_t *sm = &sr_main;
+  u32 n_left_from, next_index, *from, *to_next;
+  u32 cnt_packets = 0;
+
+  from = vlib_frame_vector_args (frame);
+  n_left_from = frame->n_vectors;
+  next_index = node->cached_next_index;
+
+  u32 thread_index = vlib_get_thread_index ();
+
+  while (n_left_from > 0)
+    {
+      u32 n_left_to_next;
+
+      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+
+      /* TODO: Dual/quad loop */
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  u32 bi0;
+	  vlib_buffer_t *b0;
+	  ip6_header_t *ip0 = 0;
+	  ip6_sr_localsid_t *ls0;
+	  u32 next0 = SRV6_AS_LOCALSID_NEXT_ERROR;
+
+	  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);
+	  ip0 = vlib_buffer_get_current (b0);
+
+	  /* Lookup the SR End behavior based on IP DA (adj) */
+	  ls0 = pool_elt_at_index (sm->localsids,
+				   vnet_buffer (b0)->ip.adj_index[VLIB_TX]);
+
+	  /* SRH processing */
+	  end_as_processing (b0, ip0, ls0->plugin_mem, &next0);
+
+	  if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
+	    {
+	      srv6_as_localsid_trace_t *tr =
+		vlib_add_trace (vm, node, b0, sizeof *tr);
+	      tr->localsid_index = ls0 - sm->localsids;
+	    }
+
+	  /* This increments the SRv6 per LocalSID counters. */
+	  vlib_increment_combined_counter (((next0 ==
+					     SRV6_AS_LOCALSID_NEXT_ERROR) ?
+					    &(sm->sr_ls_invalid_counters) :
+					    &(sm->sr_ls_valid_counters)),
+					   thread_index, ls0 - sm->localsids,
+					   1, vlib_buffer_length_in_chain (vm,
+									   b0));
+
+	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
+					   n_left_to_next, bi0, next0);
+
+	  cnt_packets++;
+	}
+
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  return frame->n_vectors;
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (srv6_as_localsid_node) = {
+  .function = srv6_as_localsid_fn,
+  .name = "srv6-as-localsid",
+  .vector_size = sizeof (u32),
+  .format_trace = format_srv6_as_localsid_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+  .n_next_nodes = SRV6_AS_LOCALSID_N_NEXT,
+  .next_nodes = {
+    [SRV6_AS_LOCALSID_NEXT_REWRITE4] = "ip4-rewrite",
+    [SRV6_AS_LOCALSID_NEXT_REWRITE6] = "ip6-rewrite",
+    [SRV6_AS_LOCALSID_NEXT_ERROR] = "error-drop",
+  },
+};
+/* *INDENT-ON* */
+
+
+/******************************* Rewriting node *******************************/
+
+/**
+ * @brief Graph node for applying a SR policy into an IPv6 packet. Encapsulation
+ */
+static uword
+srv6_as4_rewrite_fn (vlib_main_t * vm,
+		     vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  ip6_sr_main_t *srm = &sr_main;
+  srv6_as_main_t *sm = &srv6_as_main;
+  u32 n_left_from, next_index, *from, *to_next;
+  u32 cnt_packets = 0;
+
+  from = vlib_frame_vector_args (frame);
+  n_left_from = frame->n_vectors;
+  next_index = node->cached_next_index;
+
+  while (n_left_from > 0)
+    {
+      u32 n_left_to_next;
+
+      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+
+      /* TODO: Dual/quad loop */
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  u32 bi0;
+	  vlib_buffer_t *b0;
+	  ip4_header_t *ip0_encap = 0;
+	  ip6_header_t *ip0 = 0;
+	  ip6_sr_localsid_t *ls0;
+	  srv6_as_localsid_t *ls0_mem;
+	  u32 next0 = SRV6_AS_REWRITE_NEXT_LOOKUP;
+	  u16 new_l0 = 0;
+
+	  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);
+	  ip0_encap = vlib_buffer_get_current (b0);
+	  ls0 = pool_elt_at_index (srm->localsids,
+				   sm->sw_iface_localsid4[vnet_buffer
+							  (b0)->sw_if_index
+							  [VLIB_RX]]);
+	  ls0_mem = ls0->plugin_mem;
+
+	  if (PREDICT_FALSE (ls0_mem == NULL || ls0_mem->rewrite == NULL))
+	    {
+	      next0 = SRV6_AS_REWRITE_NEXT_ERROR;
+	      b0->error = node->errors[SRV6_AS_REWRITE_COUNTER_NO_RW];
+	    }
+	  else
+	    {
+	      ASSERT (VLIB_BUFFER_PRE_DATA_SIZE >=
+		      (vec_len (ls0_mem->rewrite) + b0->current_data));
+
+	      clib_memcpy (((u8 *) ip0_encap) - vec_len (ls0_mem->rewrite),
+			   ls0_mem->rewrite, vec_len (ls0_mem->rewrite));
+	      vlib_buffer_advance (b0, -(word) vec_len (ls0_mem->rewrite));
+
+	      ip0 = vlib_buffer_get_current (b0);
+
+	      /* Update inner IPv4 TTL and checksum */
+	      u32 checksum0;
+	      ip0_encap->ttl -= 1;
+	      checksum0 = ip0_encap->checksum + clib_host_to_net_u16 (0x0100);
+	      checksum0 += checksum0 >= 0xffff;
+	      ip0_encap->checksum = checksum0;
+
+	      /* Update outer IPv6 length (in case it has changed) */
+	      new_l0 = vec_len (ls0_mem->rewrite) - sizeof (ip6_header_t) +
+		clib_net_to_host_u16 (ip0_encap->length);
+	      ip0->payload_length = clib_host_to_net_u16 (new_l0);
+	    }
+
+	  if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE) &&
+	      PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
+	    {
+	      srv6_as_rewrite_trace_t *tr =
+		vlib_add_trace (vm, node, b0, sizeof *tr);
+	      clib_memcpy (tr->src.as_u8, ip0->src_address.as_u8,
+			   sizeof tr->src.as_u8);
+	      clib_memcpy (tr->dst.as_u8, ip0->dst_address.as_u8,
+			   sizeof tr->dst.as_u8);
+	    }
+
+	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
+					   n_left_to_next, bi0, next0);
+
+	  cnt_packets++;
+	}
+
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  /* Update counters */
+  vlib_node_increment_counter (vm, srv6_as4_rewrite_node.index,
+			       SRV6_AS_REWRITE_COUNTER_PROCESSED,
+			       cnt_packets);
+
+  return frame->n_vectors;
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (srv6_as4_rewrite_node) = {
+  .function = srv6_as4_rewrite_fn,
+  .name = "srv6-as4-rewrite",
+  .vector_size = sizeof (u32),
+  .format_trace = format_srv6_as_rewrite_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+  .n_errors = SRV6_AS_REWRITE_N_COUNTERS,
+  .error_strings = srv6_as_rewrite_counter_strings,
+  .n_next_nodes = SRV6_AS_REWRITE_N_NEXT,
+  .next_nodes = {
+    [SRV6_AS_REWRITE_NEXT_LOOKUP] = "ip6-lookup",
+    [SRV6_AS_REWRITE_NEXT_ERROR] = "error-drop",
+  },
+};
+/* *INDENT-ON* */
+
+
+/**
+ * @brief Graph node for applying a SR policy into an IPv6 packet. Encapsulation
+ */
+static uword
+srv6_as6_rewrite_fn (vlib_main_t * vm,
+		     vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  ip6_sr_main_t *srm = &sr_main;
+  srv6_as_main_t *sm = &srv6_as_main;
+  u32 n_left_from, next_index, *from, *to_next;
+  u32 cnt_packets = 0;
+
+  from = vlib_frame_vector_args (frame);
+  n_left_from = frame->n_vectors;
+  next_index = node->cached_next_index;
+
+  while (n_left_from > 0)
+    {
+      u32 n_left_to_next;
+
+      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+
+      /* TODO: Dual/quad loop */
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  u32 bi0;
+	  vlib_buffer_t *b0;
+	  ip6_header_t *ip0 = 0, *ip0_encap = 0;
+	  ip6_sr_localsid_t *ls0;
+	  srv6_as_localsid_t *ls0_mem;
+	  u32 next0 = SRV6_AS_REWRITE_NEXT_LOOKUP;
+	  u16 new_l0 = 0;
+
+	  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);
+	  ip0_encap = vlib_buffer_get_current (b0);
+	  ls0 = pool_elt_at_index (srm->localsids,
+				   sm->sw_iface_localsid6[vnet_buffer
+							  (b0)->sw_if_index
+							  [VLIB_RX]]);
+	  ls0_mem = ls0->plugin_mem;
+
+	  if (PREDICT_FALSE (ls0_mem == NULL || ls0_mem->rewrite == NULL))
+	    {
+	      next0 = SRV6_AS_REWRITE_NEXT_ERROR;
+	      b0->error = node->errors[SRV6_AS_REWRITE_COUNTER_NO_RW];
+	    }
+	  else
+	    {
+	      ASSERT (VLIB_BUFFER_PRE_DATA_SIZE >=
+		      (vec_len (ls0_mem->rewrite) + b0->current_data));
+
+	      clib_memcpy (((u8 *) ip0_encap) - vec_len (ls0_mem->rewrite),
+			   ls0_mem->rewrite, vec_len (ls0_mem->rewrite));
+	      vlib_buffer_advance (b0, -(word) vec_len (ls0_mem->rewrite));
+
+	      ip0 = vlib_buffer_get_current (b0);
+
+	      /* Update inner IPv6 hop limit */
+	      ip0_encap->hop_limit -= 1;
+
+	      /* Update outer IPv6 length (in case it has changed) */
+	      new_l0 = vec_len (ls0_mem->rewrite) +
+		clib_net_to_host_u16 (ip0_encap->payload_length);
+	      ip0->payload_length = clib_host_to_net_u16 (new_l0);
+	    }
+
+	  if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE) &&
+	      PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
+	    {
+	      srv6_as_rewrite_trace_t *tr =
+		vlib_add_trace (vm, node, b0, sizeof *tr);
+	      clib_memcpy (tr->src.as_u8, ip0->src_address.as_u8,
+			   sizeof tr->src.as_u8);
+	      clib_memcpy (tr->dst.as_u8, ip0->dst_address.as_u8,
+			   sizeof tr->dst.as_u8);
+	    }
+
+	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
+					   n_left_to_next, bi0, next0);
+
+	  cnt_packets++;
+	}
+
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  /* Update counters */
+  vlib_node_increment_counter (vm, srv6_as6_rewrite_node.index,
+			       SRV6_AS_REWRITE_COUNTER_PROCESSED,
+			       cnt_packets);
+
+  return frame->n_vectors;
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (srv6_as6_rewrite_node) = {
+  .function = srv6_as6_rewrite_fn,
+  .name = "srv6-as6-rewrite",
+  .vector_size = sizeof (u32),
+  .format_trace = format_srv6_as_rewrite_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+  .n_errors = SRV6_AS_REWRITE_N_COUNTERS,
+  .error_strings = srv6_as_rewrite_counter_strings,
+  .n_next_nodes = SRV6_AS_REWRITE_N_NEXT,
+  .next_nodes = {
+    [SRV6_AS_REWRITE_NEXT_LOOKUP] = "ip6-lookup",
+    [SRV6_AS_REWRITE_NEXT_ERROR] = "error-drop",
+  },
+};
+/* *INDENT-ON* */
+
+/*
+* fd.io coding-style-patch-verification: ON
+*
+* Local Variables:
+* eval: (c-set-style "gnu")
+* End:
+*/
diff --git a/src/plugins/srv6_as.am b/src/plugins/srv6_as.am
new file mode 100644
index 00000000000..09a41b9239e
--- /dev/null
+++ b/src/plugins/srv6_as.am
@@ -0,0 +1,23 @@
+# Copyright (c) 2016 Cisco Systems, Inc.
+# 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.
+
+vppplugins_LTLIBRARIES += srv6as_plugin.la
+
+srv6as_plugin_la_SOURCES =			\
+	srv6-as/as.c	\
+	srv6-as/node.c
+
+noinst_HEADERS += srv6-as/as.h
+
+# vi:syntax=automake
+