src/plugins/srv6-am/am.c

   1 /*
   2  * Copyright (c) 2015 Cisco and/or its affiliates.
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  */
  15 /*
  16  *------------------------------------------------------------------
  17  * am.c - SRv6 Masquerading Proxy (AM) function
  18  *------------------------------------------------------------------
  19  */
  20
  21 #include <vnet/vnet.h>
  22 #include <vnet/adj/adj.h>
  23 #include <vnet/plugin/plugin.h>
  24 #include <vpp/app/version.h>
  25 #include <srv6-am/am.h>
  26
  27 unsigned char function_name[] = "SRv6-AM-plugin";
  28 unsigned char keyword_str[] = "End.AM";
  29 unsigned char def_str[] = "Endpoint to SR-unaware appliance via masquerading";
  30 unsigned char params_str[] = "nh <next-hop> oif <iface-out> iif <iface-in>";
  31
  32
  33 /*****************************************/
  34 /* SRv6 LocalSID instantiation and removal functions */
  35 static int
  36 srv6_am_localsid_creation_fn (ip6_sr_localsid_t * localsid)
  37 {
  38   srv6_am_main_t *sm = &srv6_am_main;
  39   srv6_am_localsid_t *ls_mem = localsid->plugin_mem;
  40   adj_index_t nh_adj_index = ADJ_INDEX_INVALID;
  41
  42   /* Step 1: Prepare xconnect adjacency for sending packets to the VNF */
  43
  44   /* Retrieve the adjacency corresponding to the (OIF, next_hop) */
  45   nh_adj_index = adj_nbr_add_or_lock (FIB_PROTOCOL_IP6,
  46                                       VNET_LINK_IP6, &ls_mem->nh_addr,
  47                                       ls_mem->sw_if_index_out);
  48   if (nh_adj_index == ADJ_INDEX_INVALID)
  49     return -5;
  50
  51   localsid->nh_adj = nh_adj_index;
  52
  53
  54   /* Step 2: Prepare inbound policy for packets returning from the VNF */
  55
  56   /* Sanitise the SW_IF_INDEX */
  57   if (pool_is_free_index (sm->vnet_main->interface_main.sw_interfaces,
  58                           ls_mem->sw_if_index_in))
  59     return -3;
  60
  61   vnet_sw_interface_t *sw = vnet_get_sw_interface (sm->vnet_main,
  62                                                    ls_mem->sw_if_index_in);
  63   if (sw->type != VNET_SW_INTERFACE_TYPE_HARDWARE)
  64     return -3;
  65
  66   int ret = vnet_feature_enable_disable ("ip6-unicast", "srv6-am-rewrite",
  67                                          ls_mem->sw_if_index_in, 1, 0, 0);
  68   if (ret != 0)
  69     return -1;
  70
  71   return 0;
  72 }
  73
  74 static int
  75 srv6_am_localsid_removal_fn (ip6_sr_localsid_t * localsid)
  76 {
  77   srv6_am_localsid_t *ls_mem = localsid->plugin_mem;
  78
  79   /* Remove hardware indirection (from sr_steering.c:137) */
  80   int ret = vnet_feature_enable_disable ("ip6-unicast", "srv6-am-rewrite",
  81                                          ls_mem->sw_if_index_in, 0, 0, 0);
  82   if (ret != 0)
  83     return -1;
  84
  85   /* Unlock (OIF, NHOP) adjacency (from sr_localsid.c:103) */
  86   adj_unlock (localsid->nh_adj);
  87
  88   /* Clean up local SID memory */
  89   clib_mem_free (localsid->plugin_mem);
  90
  91   return 0;
  92 }
  93
  94 /**********************************/
  95 /* SRv6 LocalSID format functions */
  96 /*
  97  * Prints nicely the parameters of a localsid
  98  * Example: print "Table 5"
  99  */
 100 u8 *
 101 format_srv6_am_localsid (u8 * s, va_list * args)
 102 {
 103   srv6_am_localsid_t *ls_mem = va_arg (*args, void *);
 104
 105   vnet_main_t *vnm = vnet_get_main ();
 106
 107   return (format (s,
 108                   "Next-hop:\t%U\n"
 109                   "\tOutgoing iface: %U\n"
 110                   "\tIncoming iface: %U",
 111                   format_ip6_address, &ls_mem->nh_addr.ip6,
 112                   format_vnet_sw_if_index_name, vnm, ls_mem->sw_if_index_out,
 113                   format_vnet_sw_if_index_name, vnm, ls_mem->sw_if_index_in));
 114 }
 115
 116 /*
 117  * Process the parameters of a localsid
 118  * Example: process from:
 119  * sr localsid address cafe::1 behavior new_srv6_localsid 5
 120  * everything from behavior on... so in this case 'new_srv6_localsid 5'
 121  * Notice that it MUST match the keyword_str and params_str defined above.
 122  */
 123 uword
 124 unformat_srv6_am_localsid (unformat_input_t * input, va_list * args)
 125 {
 126   void **plugin_mem_p = va_arg (*args, void **);
 127   srv6_am_localsid_t *ls_mem;
 128
 129   vnet_main_t *vnm = vnet_get_main ();
 130
 131   ip46_address_t nh_addr;
 132   u32 sw_if_index_out;
 133   u32 sw_if_index_in;
 134
 135   if (unformat (input, "end.am nh %U oif %U iif %U",
 136                 unformat_ip6_address, &nh_addr.ip6,
 137                 unformat_vnet_sw_interface, vnm, &sw_if_index_out,
 138                 unformat_vnet_sw_interface, vnm, &sw_if_index_in))
 139     {
 140       /* Allocate a portion of memory */
 141       ls_mem = clib_mem_alloc_aligned_at_offset (sizeof *ls_mem, 0, 0, 1);
 142
 143       /* Set to zero the memory */
 144       clib_memset (ls_mem, 0, sizeof *ls_mem);
 145
 146       /* Our brand-new car is ready */
 147       clib_memcpy (&ls_mem->nh_addr.ip6, &nh_addr.ip6,
 148                    sizeof (ip6_address_t));
 149       ls_mem->sw_if_index_out = sw_if_index_out;
 150       ls_mem->sw_if_index_in = sw_if_index_in;
 151
 152       /* Dont forget to add it to the localsid */
 153       *plugin_mem_p = ls_mem;
 154       return 1;
 155     }
 156   return 0;
 157 }
 158
 159 /*************************/
 160 /* SRv6 LocalSID FIB DPO */
 161 static u8 *
 162 format_srv6_am_dpo (u8 * s, va_list * args)
 163 {
 164   index_t index = va_arg (*args, index_t);
 165   CLIB_UNUSED (u32 indent) = va_arg (*args, u32);
 166
 167   return (format (s, "SR: dynamic_proxy_index:[%u]", index));
 168 }
 169
 170 void
 171 srv6_am_dpo_lock (dpo_id_t * dpo)
 172 {
 173 }
 174
 175 void
 176 srv6_am_dpo_unlock (dpo_id_t * dpo)
 177 {
 178 }
 179
 180 const static dpo_vft_t srv6_am_vft = {
 181   .dv_lock = srv6_am_dpo_lock,
 182   .dv_unlock = srv6_am_dpo_unlock,
 183   .dv_format = format_srv6_am_dpo,
 184 };
 185
 186 const static char *const srv6_am_ip6_nodes[] = {
 187   "srv6-am-localsid",
 188   NULL,
 189 };
 190
 191 const static char *const *const srv6_am_nodes[DPO_PROTO_NUM] = {
 192   [DPO_PROTO_IP6] = srv6_am_ip6_nodes,
 193 };
 194
 195 /**********************/
 196 static clib_error_t *
 197 srv6_am_init (vlib_main_t * vm)
 198 {
 199   srv6_am_main_t *sm = &srv6_am_main;
 200   int rv = 0;
 201
 202   sm->vlib_main = vm;
 203   sm->vnet_main = vnet_get_main ();
 204
 205   /* Create DPO */
 206   sm->srv6_am_dpo_type = dpo_register_new_type (&srv6_am_vft, srv6_am_nodes);
 207
 208   /* Register SRv6 LocalSID */
 209   rv = sr_localsid_register_function (vm,
 210                                       function_name,
 211                                       keyword_str,
 212                                       def_str,
 213                                       params_str,
 214                                       &sm->srv6_am_dpo_type,
 215                                       format_srv6_am_localsid,
 216                                       unformat_srv6_am_localsid,
 217                                       srv6_am_localsid_creation_fn,
 218                                       srv6_am_localsid_removal_fn);
 219   if (rv < 0)
 220     clib_error_return (0, "SRv6 LocalSID function could not be registered.");
 221   else
 222     sm->srv6_localsid_behavior_id = rv;
 223
 224   return 0;
 225 }
 226
 227 /* *INDENT-OFF* */
 228 VNET_FEATURE_INIT (srv6_am_rewrite, static) =
 229 {
 230   .arc_name = "ip6-unicast",
 231   .node_name = "srv6-am-rewrite",
 232   .runs_before = 0,
 233 };
 234
 235 VLIB_INIT_FUNCTION (srv6_am_init);
 236
 237 VLIB_PLUGIN_REGISTER () = {
 238   .version = VPP_BUILD_VER,
 239   .description = "Masquerading SRv6 proxy",
 240 };
 241 /* *INDENT-ON* */
 242
 243 /*
 244 * fd.io coding-style-patch-verification: ON
 245 *
 246 * Local Variables:
 247 * eval: (c-set-style "gnu")
 248 * End:
 249 */