SRv6 static proxy plugin

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

1 files changed, 502 insertions, 0 deletions

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:
+*/