src/vnet/ipsec/ipsec_tun.c

   1 /*
   2  * ipsec_tun.h : IPSEC tunnel protection
   3  *
   4  * Copyright (c) 2015 Cisco and/or its affiliates.
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at:
   8  *
   9  *     http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 #include <vnet/ipsec/ipsec_tun.h>
  19 #include <vnet/ipsec/ipsec_itf.h>
  20 #include <vnet/ipsec/esp.h>
  21 #include <vnet/udp/udp_local.h>
  22 #include <vnet/adj/adj_delegate.h>
  23 #include <vnet/adj/adj_midchain.h>
  24 #include <vnet/teib/teib.h>
  25 #include <vnet/mpls/mpls.h>
  26
  27 /* instantiate the bihash functions */
  28 #include <vppinfra/bihash_8_16.h>
  29 #include <vppinfra/bihash_template.c>
  30 #include <vppinfra/bihash_24_16.h>
  31 #include <vppinfra/bihash_template.c>
  32
  33 #define IPSEC_TUN_DEFAULT_HASH_NUM_BUCKETS (64 * 1024)
  34 #define IPSEC_TUN_DEFAULT_HASH_MEMORY_SIZE 512 << 20
  35
  36 /**
  37  * The logger
  38  */
  39 vlib_log_class_t ipsec_tun_protect_logger;
  40
  41 /**
  42  * Pool of tunnel protection objects
  43  */
  44 ipsec_tun_protect_t *ipsec_tun_protect_pool;
  45
  46 /**
  47  * Adj delegate registered type
  48  */
  49 static adj_delegate_type_t ipsec_tun_adj_delegate_type;
  50
  51 /**
  52  * Adj index to TX SA mapping
  53  */
  54 index_t *ipsec_tun_protect_sa_by_adj_index;
  55
  56 const ip_address_t IP_ADDR_ALL_0 = IP_ADDRESS_V4_ALL_0S;
  57
  58 /**
  59  * The DB of all added per-nh tunnel protectiond
  60  */
  61 typedef struct ipsec_tun_protect_itf_db_t_
  62 {
  63   /** A hash table key'd on IP (4 or 6) address */
  64   uword *id_hash;
  65   /** If the interface is P2P then there is only one protect
  66    * object associated with the auto-adj for each NH proto */
  67   index_t id_itp;
  68 } ipsec_tun_protect_itf_db_t;
  69
  70 typedef struct ipsec_tun_protect_db_t_
  71 {
  72   /** Per-interface vector */
  73   ipsec_tun_protect_itf_db_t *id_itf;
  74 } ipsec_tun_protect_db_t;
  75
  76 static ipsec_tun_protect_db_t itp_db;
  77
  78 const static ipsec_tun_protect_itf_db_t IPSEC_TUN_PROTECT_DEFAULT_DB_ENTRY = {
  79   .id_itp = INDEX_INVALID,
  80 };
  81
  82 #define ITP_DBG(_itp, _fmt, _args...)                   \
  83 {                                                       \
  84   vlib_log_debug(ipsec_tun_protect_logger,              \
  85                  "[%U]: " _fmt,                         \
  86                  format_ipsec_tun_protect,              \
  87                  _itp, ##_args);                        \
  88 }
  89
  90 #define ITP_DBG2(_fmt, _args...)                        \
  91 {                                                       \
  92   vlib_log_debug(ipsec_tun_protect_logger,              \
  93                  _fmt, ##_args);                        \
  94 }
  95
  96 static u32 ipsec_tun_node_regs[N_AF];
  97
  98 void
  99 ipsec_tun_register_nodes (ip_address_family_t af)
 100 {
 101   if (0 == ipsec_tun_node_regs[af]++)
 102     {
 103       if (AF_IP4 == af)
 104         ip4_register_protocol (IP_PROTOCOL_IPSEC_ESP,
 105                                ipsec4_tun_input_node.index);
 106       else
 107         ip6_register_protocol (IP_PROTOCOL_IPSEC_ESP,
 108                                ipsec6_tun_input_node.index);
 109       ipsec_register_udp_port (UDP_DST_PORT_ipsec, (AF_IP4 == af));
 110     }
 111 }
 112
 113 void
 114 ipsec_tun_unregister_nodes (ip_address_family_t af)
 115 {
 116   ASSERT (0 != ipsec_tun_node_regs[af]);
 117   if (0 == --ipsec_tun_node_regs[af])
 118     {
 119       if (AF_IP4 == af)
 120         ip4_unregister_protocol (IP_PROTOCOL_IPSEC_ESP);
 121       else
 122         ip6_unregister_protocol (IP_PROTOCOL_IPSEC_ESP);
 123       ipsec_unregister_udp_port (UDP_DST_PORT_ipsec, (AF_IP4 == af));
 124     }
 125 }
 126
 127 static inline const ipsec_tun_protect_t *
 128 ipsec_tun_protect_from_const_base (const adj_delegate_t * ad)
 129 {
 130   if (ad == NULL)
 131     return (NULL);
 132   return (pool_elt_at_index (ipsec_tun_protect_pool, ad->ad_index));
 133 }
 134
 135 static u32
 136 ipsec_tun_protect_get_adj_next (vnet_link_t linkt,
 137                                 const ipsec_tun_protect_t *itp)
 138 {
 139   ipsec_main_t *im;
 140   u32 next;
 141
 142   im = &ipsec_main;
 143   next = 0;
 144
 145   if (!(itp->itp_flags & IPSEC_PROTECT_ITF))
 146     {
 147       if (ip46_address_is_ip4 (&itp->itp_tun.src))
 148         linkt = VNET_LINK_IP4;
 149       else
 150         linkt = VNET_LINK_IP6;
 151     }
 152
 153   switch (linkt)
 154     {
 155     case VNET_LINK_IP4:
 156       next = im->esp4_encrypt_tun_node_index;
 157       break;
 158     case VNET_LINK_IP6:
 159       next = im->esp6_encrypt_tun_node_index;
 160       break;
 161     case VNET_LINK_MPLS:
 162       next = im->esp_mpls_encrypt_tun_node_index;
 163       break;
 164     case VNET_LINK_ARP:
 165     case VNET_LINK_NSH:
 166     case VNET_LINK_ETHERNET:
 167       ASSERT (0);
 168       break;
 169     }
 170
 171   return (next);
 172 }
 173
 174 static void
 175 ipsec_tun_setup_tx_nodes (u32 sw_if_index, const ipsec_tun_protect_t *itp)
 176 {
 177   vnet_feature_modify_end_node (
 178     ip4_main.lookup_main.output_feature_arc_index, sw_if_index,
 179     ipsec_tun_protect_get_adj_next (VNET_LINK_IP4, itp));
 180   vnet_feature_modify_end_node (
 181     ip6_main.lookup_main.output_feature_arc_index, sw_if_index,
 182     ipsec_tun_protect_get_adj_next (VNET_LINK_IP6, itp));
 183   vnet_feature_modify_end_node (
 184     mpls_main.output_feature_arc_index, sw_if_index,
 185     ipsec_tun_protect_get_adj_next (VNET_LINK_MPLS, itp));
 186 }
 187
 188 static void
 189 ipsec_tun_protect_add_adj (adj_index_t ai, const ipsec_tun_protect_t * itp)
 190 {
 191   vec_validate_init_empty (ipsec_tun_protect_sa_by_adj_index, ai,
 192                            INDEX_INVALID);
 193
 194   if (NULL == itp)
 195     {
 196       ipsec_tun_protect_sa_by_adj_index[ai] = INDEX_INVALID;
 197       adj_nbr_midchain_reset_next_node (ai);
 198     }
 199   else
 200     {
 201       ipsec_tun_protect_sa_by_adj_index[ai] = itp->itp_out_sa;
 202       adj_nbr_midchain_update_next_node (
 203         ai, ipsec_tun_protect_get_adj_next (adj_get_link_type (ai), itp));
 204     }
 205 }
 206
 207 static index_t
 208 ipsec_tun_protect_find (u32 sw_if_index, const ip_address_t * nh)
 209 {
 210   ipsec_tun_protect_itf_db_t *idi;
 211   uword *p;
 212
 213   if (vec_len (itp_db.id_itf) <= sw_if_index)
 214     return INDEX_INVALID;
 215
 216   if (vnet_sw_interface_is_p2p (vnet_get_main (), sw_if_index))
 217     return (itp_db.id_itf[sw_if_index].id_itp);
 218
 219   idi = &itp_db.id_itf[sw_if_index];
 220   p = hash_get_mem (idi->id_hash, nh);
 221
 222   if (NULL == p)
 223     {
 224       return INDEX_INVALID;
 225     }
 226   return (p[0]);
 227 }
 228
 229 static void
 230 ipsec_tun_protect_rx_db_add (ipsec_main_t * im,
 231                              const ipsec_tun_protect_t * itp)
 232 {
 233   const ipsec_sa_t *sa;
 234   u32 sai;
 235
 236   if (ip46_address_is_zero (&itp->itp_crypto.dst))
 237     return;
 238
 239   /* *INDENT-OFF* */
 240   FOR_EACH_IPSEC_PROTECT_INPUT_SAI(itp, sai,
 241   ({
 242       sa = ipsec_sa_get (sai);
 243
 244       ipsec_tun_lkup_result_t res = {
 245         .tun_index = itp - ipsec_tun_protect_pool,
 246         .sa_index = sai,
 247         .flags = itp->itp_flags,
 248         .sw_if_index = itp->itp_sw_if_index,
 249       };
 250
 251       /*
 252        * The key is formed from the tunnel's destination
 253        * as the packet lookup is done from the packet's source
 254        */
 255       if (ip46_address_is_ip4 (&itp->itp_crypto.dst))
 256         {
 257           ipsec4_tunnel_kv_t key = {
 258             .value = res,
 259           };
 260           clib_bihash_kv_8_16_t *bkey = (clib_bihash_kv_8_16_t*)&key;
 261
 262           ipsec4_tunnel_mk_key(&key, &itp->itp_crypto.dst.ip4,
 263                                clib_host_to_net_u32 (sa->spi));
 264
 265           if (!clib_bihash_is_initialised_8_16 (&im->tun4_protect_by_key))
 266             clib_bihash_init_8_16 (&im->tun4_protect_by_key,
 267                                    "IPSec IPv4 tunnels",
 268                                    IPSEC_TUN_DEFAULT_HASH_NUM_BUCKETS,
 269                                    IPSEC_TUN_DEFAULT_HASH_MEMORY_SIZE);
 270
 271           clib_bihash_add_del_8_16 (&im->tun4_protect_by_key, bkey, 1);
 272           ipsec_tun_register_nodes (AF_IP4);
 273         }
 274       else
 275         {
 276           ipsec6_tunnel_kv_t key = {
 277             .key = {
 278               .remote_ip = itp->itp_crypto.dst.ip6,
 279               .spi = clib_host_to_net_u32 (sa->spi),
 280             },
 281             .value = res,
 282           };
 283           clib_bihash_kv_24_16_t *bkey = (clib_bihash_kv_24_16_t*)&key;
 284
 285           if (!clib_bihash_is_initialised_24_16 (&im->tun6_protect_by_key))
 286             clib_bihash_init_24_16 (&im->tun6_protect_by_key,
 287                                     "IPSec IPv6 tunnels",
 288                                     IPSEC_TUN_DEFAULT_HASH_NUM_BUCKETS,
 289                                     IPSEC_TUN_DEFAULT_HASH_MEMORY_SIZE);
 290           clib_bihash_add_del_24_16 (&im->tun6_protect_by_key, bkey, 1);
 291           ipsec_tun_register_nodes (AF_IP6);
 292         }
 293   }))
 294   /* *INDENT-ON* */
 295 }
 296
 297 static adj_walk_rc_t
 298 ipsec_tun_protect_adj_add (adj_index_t ai, void *arg)
 299 {
 300   ipsec_tun_protect_t *itp = arg;
 301   adj_delegate_add (adj_get (ai), ipsec_tun_adj_delegate_type,
 302                     itp - ipsec_tun_protect_pool);
 303   ipsec_tun_protect_add_adj (ai, itp);
 304
 305   if (itp->itp_flags & IPSEC_PROTECT_ITF)
 306     ipsec_itf_adj_stack (ai, itp->itp_out_sa);
 307
 308   return (ADJ_WALK_RC_CONTINUE);
 309 }
 310
 311 static void
 312 ipsec_tun_protect_tx_db_add (ipsec_tun_protect_t * itp)
 313 {
 314   /*
 315    * add the delegate to the adj
 316    */
 317   ipsec_tun_protect_itf_db_t *idi;
 318   fib_protocol_t nh_proto;
 319   ip46_address_t nh;
 320
 321   vec_validate_init_empty (itp_db.id_itf,
 322                            itp->itp_sw_if_index,
 323                            IPSEC_TUN_PROTECT_DEFAULT_DB_ENTRY);
 324
 325   idi = &itp_db.id_itf[itp->itp_sw_if_index];
 326
 327   if (vnet_sw_interface_is_p2p (vnet_get_main (), itp->itp_sw_if_index))
 328     {
 329       if (INDEX_INVALID == idi->id_itp)
 330         {
 331           ipsec_tun_setup_tx_nodes (itp->itp_sw_if_index, itp);
 332         }
 333       idi->id_itp = itp - ipsec_tun_protect_pool;
 334
 335       FOR_EACH_FIB_IP_PROTOCOL (nh_proto)
 336         adj_nbr_walk (itp->itp_sw_if_index,
 337                       nh_proto, ipsec_tun_protect_adj_add, itp);
 338     }
 339   else
 340     {
 341       if (NULL == idi->id_hash)
 342         {
 343           idi->id_hash =
 344             hash_create_mem (0, sizeof (ip_address_t), sizeof (uword));
 345           /*
 346            * enable the encrypt feature for egress if this is the first addition
 347            * on this interface
 348            */
 349           ipsec_tun_setup_tx_nodes (itp->itp_sw_if_index, itp);
 350         }
 351
 352       hash_set_mem (idi->id_hash, itp->itp_key, itp - ipsec_tun_protect_pool);
 353
 354       /*
 355        * walk all the adjs with the same nh on this interface
 356        * to associate them with this protection
 357        */
 358       nh_proto = ip_address_to_46 (itp->itp_key, &nh);
 359
 360       adj_nbr_walk_nh (itp->itp_sw_if_index,
 361                        nh_proto, &nh, ipsec_tun_protect_adj_add, itp);
 362
 363       ipsec_tun_register_nodes (FIB_PROTOCOL_IP6 == nh_proto ?
 364                                 AF_IP6 : AF_IP4);
 365     }
 366 }
 367
 368 static void
 369 ipsec_tun_protect_rx_db_remove (ipsec_main_t * im,
 370                                 const ipsec_tun_protect_t * itp)
 371 {
 372   const ipsec_sa_t *sa;
 373
 374   /* *INDENT-OFF* */
 375   FOR_EACH_IPSEC_PROTECT_INPUT_SA(itp, sa,
 376   ({
 377     if (ip46_address_is_ip4 (&itp->itp_crypto.dst))
 378       {
 379           ipsec4_tunnel_kv_t key;
 380           clib_bihash_kv_8_16_t res, *bkey = (clib_bihash_kv_8_16_t*)&key;
 381
 382           ipsec4_tunnel_mk_key(&key, &itp->itp_crypto.dst.ip4,
 383                                clib_host_to_net_u32 (sa->spi));
 384
 385           if (!clib_bihash_search_8_16 (&im->tun4_protect_by_key, bkey, &res))
 386             {
 387               clib_bihash_add_del_8_16 (&im->tun4_protect_by_key, bkey, 0);
 388               ipsec_tun_unregister_nodes(AF_IP4);
 389             }
 390       }
 391     else
 392       {
 393         ipsec6_tunnel_kv_t key = {
 394           .key = {
 395             .remote_ip = itp->itp_crypto.dst.ip6,
 396             .spi = clib_host_to_net_u32 (sa->spi),
 397           },
 398         };
 399         clib_bihash_kv_24_16_t res, *bkey = (clib_bihash_kv_24_16_t*)&key;
 400
 401         if (!clib_bihash_search_24_16 (&im->tun6_protect_by_key, bkey, &res))
 402           {
 403             clib_bihash_add_del_24_16 (&im->tun6_protect_by_key, bkey, 0);
 404             ipsec_tun_unregister_nodes(AF_IP6);
 405           }
 406       }
 407   }));
 408   /* *INDENT-ON* */
 409 }
 410
 411 static adj_walk_rc_t
 412 ipsec_tun_protect_adj_remove (adj_index_t ai, void *arg)
 413 {
 414   ipsec_tun_protect_t *itp = arg;
 415
 416   adj_delegate_remove (ai, ipsec_tun_adj_delegate_type);
 417   ipsec_tun_protect_add_adj (ai, NULL);
 418
 419   if (itp->itp_flags & IPSEC_PROTECT_ITF)
 420     ipsec_itf_adj_unstack (ai);
 421
 422   return (ADJ_WALK_RC_CONTINUE);
 423 }
 424
 425 static void
 426 ipsec_tun_protect_tx_db_remove (ipsec_tun_protect_t * itp)
 427 {
 428   ipsec_tun_protect_itf_db_t *idi;
 429   fib_protocol_t nh_proto;
 430   ip46_address_t nh;
 431
 432   nh_proto = ip_address_to_46 (itp->itp_key, &nh);
 433   idi = &itp_db.id_itf[itp->itp_sw_if_index];
 434
 435   if (vnet_sw_interface_is_p2p (vnet_get_main (), itp->itp_sw_if_index))
 436     {
 437       ipsec_itf_reset_tx_nodes (itp->itp_sw_if_index);
 438       idi->id_itp = INDEX_INVALID;
 439
 440       FOR_EACH_FIB_IP_PROTOCOL (nh_proto)
 441         adj_nbr_walk (itp->itp_sw_if_index,
 442                       nh_proto, ipsec_tun_protect_adj_remove, itp);
 443     }
 444   else
 445     {
 446       adj_nbr_walk_nh (itp->itp_sw_if_index,
 447                        nh_proto, &nh, ipsec_tun_protect_adj_remove, itp);
 448
 449       hash_unset_mem (idi->id_hash, itp->itp_key);
 450
 451       if (0 == hash_elts (idi->id_hash))
 452         {
 453           ipsec_itf_reset_tx_nodes (itp->itp_sw_if_index);
 454           hash_free (idi->id_hash);
 455           idi->id_hash = NULL;
 456         }
 457       ipsec_tun_unregister_nodes (FIB_PROTOCOL_IP6 == nh_proto ?
 458                                   AF_IP6 : AF_IP4);
 459     }
 460 }
 461
 462 static void
 463 ipsec_tun_protect_set_crypto_addr (ipsec_tun_protect_t * itp)
 464 {
 465   ipsec_sa_t *sa;
 466
 467   /* *INDENT-OFF* */
 468   FOR_EACH_IPSEC_PROTECT_INPUT_SA(itp, sa,
 469   ({
 470     if (ipsec_sa_is_set_IS_TUNNEL (sa))
 471       {
 472         itp->itp_crypto.src = ip_addr_46 (&sa->tunnel.t_dst);
 473         itp->itp_crypto.dst = ip_addr_46 (&sa->tunnel.t_src);
 474         if (!(itp->itp_flags & IPSEC_PROTECT_ITF))
 475           {
 476             ipsec_sa_set_IS_PROTECT (sa);
 477             itp->itp_flags |= IPSEC_PROTECT_ENCAPED;
 478           }
 479       }
 480     else
 481       {
 482         itp->itp_crypto.src = itp->itp_tun.src;
 483         itp->itp_crypto.dst = itp->itp_tun.dst;
 484         itp->itp_flags &= ~IPSEC_PROTECT_ENCAPED;
 485       }
 486   }));
 487   /* *INDENT-ON* */
 488 }
 489
 490 static void
 491 ipsec_tun_protect_config (ipsec_main_t * im,
 492                           ipsec_tun_protect_t * itp, u32 sa_out, u32 * sas_in)
 493 {
 494   index_t sai;
 495   u32 ii;
 496
 497   itp->itp_n_sa_in = vec_len (sas_in);
 498   for (ii = 0; ii < itp->itp_n_sa_in; ii++)
 499     itp->itp_in_sas[ii] = sas_in[ii];
 500   itp->itp_out_sa = sa_out;
 501
 502   ipsec_sa_lock (itp->itp_out_sa);
 503
 504   if (itp->itp_flags & IPSEC_PROTECT_ITF)
 505     ipsec_sa_set_NO_ALGO_NO_DROP (ipsec_sa_get (itp->itp_out_sa));
 506
 507   /* *INDENT-OFF* */
 508   FOR_EACH_IPSEC_PROTECT_INPUT_SAI(itp, sai,
 509   ({
 510     ipsec_sa_lock(sai);
 511   }));
 512   ipsec_tun_protect_set_crypto_addr(itp);
 513   /* *INDENT-ON* */
 514
 515   /*
 516    * add to the DB against each SA
 517    */
 518   ipsec_tun_protect_rx_db_add (im, itp);
 519   ipsec_tun_protect_tx_db_add (itp);
 520
 521   ITP_DBG (itp, "configured");
 522 }
 523
 524 static void
 525 ipsec_tun_protect_unconfig (ipsec_main_t * im, ipsec_tun_protect_t * itp)
 526 {
 527   ipsec_sa_t *sa;
 528   index_t sai;
 529
 530   /* *INDENT-OFF* */
 531   FOR_EACH_IPSEC_PROTECT_INPUT_SA(itp, sa,
 532   ({
 533     ipsec_sa_unset_IS_PROTECT (sa);
 534   }));
 535
 536   ipsec_tun_protect_rx_db_remove (im, itp);
 537   ipsec_tun_protect_tx_db_remove (itp);
 538
 539   ipsec_sa_unset_NO_ALGO_NO_DROP (ipsec_sa_get (itp->itp_out_sa));
 540   ipsec_sa_unlock(itp->itp_out_sa);
 541
 542   FOR_EACH_IPSEC_PROTECT_INPUT_SAI(itp, sai,
 543   ({
 544     ipsec_sa_unlock(sai);
 545   }));
 546   /* *INDENT-ON* */
 547   ITP_DBG (itp, "unconfigured");
 548 }
 549
 550 static void
 551 ipsec_tun_protect_update_from_teib (ipsec_tun_protect_t * itp,
 552                                     const teib_entry_t * ne)
 553 {
 554   if (NULL != ne)
 555     {
 556       const fib_prefix_t *pfx;
 557
 558       pfx = teib_entry_get_nh (ne);
 559
 560       ip46_address_copy (&itp->itp_tun.dst, &pfx->fp_addr);
 561     }
 562   else
 563     ip46_address_reset (&itp->itp_tun.dst);
 564 }
 565
 566 int
 567 ipsec_tun_protect_update (u32 sw_if_index,
 568                           const ip_address_t * nh, u32 sa_out, u32 * sas_in)
 569 {
 570   ipsec_tun_protect_t *itp;
 571   u32 itpi, ii, *saip;
 572   ipsec_main_t *im;
 573   int rv;
 574
 575   if (NULL == nh)
 576     nh = &IP_ADDR_ALL_0;
 577
 578   ITP_DBG2 ("update: %U/%U",
 579             format_vnet_sw_if_index_name, vnet_get_main (), sw_if_index,
 580             format_ip_address, nh);
 581
 582   if (vec_len (sas_in) > ITP_MAX_N_SA_IN)
 583     {
 584       rv = VNET_API_ERROR_LIMIT_EXCEEDED;
 585       goto out;
 586     }
 587
 588   rv = 0;
 589   im = &ipsec_main;
 590   itpi = ipsec_tun_protect_find (sw_if_index, nh);
 591
 592   vec_foreach_index (ii, sas_in)
 593   {
 594     sas_in[ii] = ipsec_sa_find_and_lock (sas_in[ii]);
 595     if (~0 == sas_in[ii])
 596       {
 597         rv = VNET_API_ERROR_INVALID_VALUE;
 598         goto out;
 599       }
 600   }
 601
 602   sa_out = ipsec_sa_find_and_lock (sa_out);
 603
 604   if (~0 == sa_out)
 605     {
 606       rv = VNET_API_ERROR_INVALID_VALUE;
 607       goto out;
 608     }
 609
 610   if (INDEX_INVALID == itpi)
 611     {
 612       vnet_device_class_t *dev_class;
 613       vnet_hw_interface_t *hi;
 614       vnet_main_t *vnm;
 615       u8 is_l2;
 616
 617       vnm = vnet_get_main ();
 618       hi = vnet_get_sup_hw_interface (vnm, sw_if_index);
 619       dev_class = vnet_get_device_class (vnm, hi->dev_class_index);
 620
 621       if (NULL == dev_class->ip_tun_desc)
 622         {
 623           rv = VNET_API_ERROR_INVALID_SW_IF_INDEX;
 624           goto out;
 625         }
 626
 627       pool_get_zero (ipsec_tun_protect_pool, itp);
 628
 629       itp->itp_sw_if_index = sw_if_index;
 630       itp->itp_ai = ADJ_INDEX_INVALID;
 631
 632       itp->itp_n_sa_in = vec_len (sas_in);
 633       for (ii = 0; ii < itp->itp_n_sa_in; ii++)
 634         itp->itp_in_sas[ii] = sas_in[ii];
 635       itp->itp_out_sa = sa_out;
 636
 637       itp->itp_key = clib_mem_alloc (sizeof (*itp->itp_key));
 638       ip_address_copy (itp->itp_key, nh);
 639
 640       rv = dev_class->ip_tun_desc (sw_if_index,
 641                                    &itp->itp_tun.src,
 642                                    &itp->itp_tun.dst, &is_l2);
 643
 644       if (rv)
 645         goto out;
 646
 647       if (ip46_address_is_zero (&itp->itp_tun.src))
 648         {
 649           /*
 650            * must be one of those pesky ipsec interfaces that has no encap.
 651            * the encap then MUST come from the tunnel mode SA.
 652            */
 653           ipsec_sa_t *sa;
 654
 655           sa = ipsec_sa_get (itp->itp_out_sa);
 656
 657           if (!ipsec_sa_is_set_IS_TUNNEL (sa))
 658             {
 659               rv = VNET_API_ERROR_INVALID_DST_ADDRESS;
 660               goto out;
 661             }
 662
 663           itp->itp_flags |= IPSEC_PROTECT_ITF;
 664         }
 665       else if (ip46_address_is_zero (&itp->itp_tun.dst))
 666         {
 667           /* tunnel has no destination address, presumably because it's p2mp
 668              in which case we use the nh that this is protection for */
 669           ipsec_tun_protect_update_from_teib
 670             (itp, teib_entry_find (sw_if_index, nh));
 671         }
 672
 673       if (is_l2)
 674         itp->itp_flags |= IPSEC_PROTECT_L2;
 675
 676       /*
 677        * add to the tunnel DB for ingress
 678        *  - if the SA is in trasnport mode, then the packates will arrive
 679        *    with the IP src,dst of the protected tunnel, in which case we can
 680        *    simply strip the IP header and hand the payload to the protocol
 681        *    appropriate input handler
 682        *  - if the SA is in tunnel mode then there are two IP headers present
 683        *    one for the crytpo tunnel endpoints (described in the SA) and one
 684        *    for the tunnel endpoints. The outer IP headers in the srriving
 685        *    packets will have the crypto endpoints. So the DB needs to contain
 686        *    the crpto endpoint. Once the crypto header is stripped, revealing,
 687        *    the tunnel-IP we have 2 choices:
 688        *     1) do a tunnel lookup based on the revealed header
 689        *     2) skip the tunnel lookup and assume that the packet matches the
 690        *        one that is protected here.
 691        *    If we did 1) then we would allow our peer to use the SA for tunnel
 692        *    X to inject traffic onto tunnel Y, this is not good. If we do 2)
 693        *    then we don't verify that the peer is indeed using SA for tunnel
 694        *    X and addressing tunnel X. So we take a compromise, once the SA
 695        *    matches to tunnel X we veriy that the inner IP matches the value
 696        *    of the tunnel we are protecting, else it's dropped.
 697        */
 698       ipsec_tun_protect_config (im, itp, sa_out, sas_in);
 699     }
 700   else
 701     {
 702       /* updating SAs only */
 703       itp = pool_elt_at_index (ipsec_tun_protect_pool, itpi);
 704
 705       ipsec_tun_protect_unconfig (im, itp);
 706       ipsec_tun_protect_config (im, itp, sa_out, sas_in);
 707     }
 708
 709   ipsec_sa_unlock (sa_out);
 710   vec_foreach (saip, sas_in) ipsec_sa_unlock (*saip);
 711   vec_free (sas_in);
 712
 713 out:
 714   return (rv);
 715 }
 716
 717 int
 718 ipsec_tun_protect_del (u32 sw_if_index, const ip_address_t * nh)
 719 {
 720   ipsec_tun_protect_t *itp;
 721   ipsec_main_t *im;
 722   index_t itpi;
 723
 724   ITP_DBG2 ("delete: %U/%U",
 725             format_vnet_sw_if_index_name, vnet_get_main (), sw_if_index,
 726             format_ip_address, nh);
 727
 728   im = &ipsec_main;
 729   if (NULL == nh)
 730     nh = &IP_ADDR_ALL_0;
 731
 732   itpi = ipsec_tun_protect_find (sw_if_index, nh);
 733
 734   if (INDEX_INVALID == itpi)
 735     return (VNET_API_ERROR_NO_SUCH_ENTRY);
 736
 737   itp = ipsec_tun_protect_get (itpi);
 738   ipsec_tun_protect_unconfig (im, itp);
 739
 740   if (ADJ_INDEX_INVALID != itp->itp_ai)
 741     adj_unlock (itp->itp_ai);
 742
 743   clib_mem_free (itp->itp_key);
 744   pool_put (ipsec_tun_protect_pool, itp);
 745
 746   return (0);
 747 }
 748
 749 void
 750 ipsec_tun_protect_walk (ipsec_tun_protect_walk_cb_t fn, void *ctx)
 751 {
 752   index_t itpi;
 753
 754   /* *INDENT-OFF* */
 755   pool_foreach_index (itpi, ipsec_tun_protect_pool)
 756    {
 757     fn (itpi, ctx);
 758   }
 759   /* *INDENT-ON* */
 760 }
 761
 762 void
 763 ipsec_tun_protect_walk_itf (u32 sw_if_index,
 764                             ipsec_tun_protect_walk_cb_t fn, void *ctx)
 765 {
 766   ipsec_tun_protect_itf_db_t *idi;
 767   ip_address_t *key;
 768   index_t itpi;
 769
 770   if (vec_len (itp_db.id_itf) <= sw_if_index)
 771     return;
 772
 773   idi = &itp_db.id_itf[sw_if_index];
 774
 775   /* *INDENT-OFF* */
 776   hash_foreach(key, itpi, idi->id_hash,
 777   ({
 778     fn (itpi, ctx);
 779   }));
 780   /* *INDENT-ON* */
 781   if (INDEX_INVALID != idi->id_itp)
 782     fn (idi->id_itp, ctx);
 783 }
 784
 785 static void
 786 ipsec_tun_feature_update (u32 sw_if_index, u8 arc_index, u8 is_enable,
 787                           void *data)
 788 {
 789   ipsec_tun_protect_t *itp;
 790   index_t itpi;
 791
 792   if (arc_index != feature_main.device_input_feature_arc_index)
 793     return;
 794
 795   /* Only p2p tunnels supported */
 796   itpi = ipsec_tun_protect_find (sw_if_index, &IP_ADDR_ALL_0);
 797   if (itpi == INDEX_INVALID)
 798     return;
 799
 800   itp = ipsec_tun_protect_get (itpi);
 801
 802   if (is_enable)
 803     {
 804       u32 decrypt_tun = ip46_address_is_ip4 (&itp->itp_crypto.dst) ?
 805                           ipsec_main.esp4_decrypt_tun_node_index :
 806                           ipsec_main.esp6_decrypt_tun_node_index;
 807
 808       if (!(itp->itp_flags & IPSEC_PROTECT_FEAT))
 809         {
 810           itp->itp_flags |= IPSEC_PROTECT_FEAT;
 811           vnet_feature_modify_end_node (
 812             feature_main.device_input_feature_arc_index, sw_if_index,
 813             decrypt_tun);
 814         }
 815     }
 816   else
 817     {
 818       if (itp->itp_flags & IPSEC_PROTECT_FEAT)
 819         {
 820           itp->itp_flags &= ~IPSEC_PROTECT_FEAT;
 821
 822           u32 eth_in =
 823             vlib_get_node_by_name (vlib_get_main (), (u8 *) "ethernet-input")
 824               ->index;
 825
 826           vnet_feature_modify_end_node (
 827             feature_main.device_input_feature_arc_index, sw_if_index, eth_in);
 828         }
 829     }
 830
 831   /* Propagate flag change into lookup entries */
 832   ipsec_tun_protect_rx_db_remove (&ipsec_main, itp);
 833   ipsec_tun_protect_rx_db_add (&ipsec_main, itp);
 834 }
 835
 836 static void
 837 ipsec_tun_protect_adj_delegate_adj_deleted (adj_delegate_t * ad)
 838 {
 839   /* remove our delegate */
 840   ipsec_tun_protect_add_adj (ad->ad_adj_index, NULL);
 841   adj_delegate_remove (ad->ad_adj_index, ipsec_tun_adj_delegate_type);
 842 }
 843
 844 static void
 845 ipsec_tun_protect_adj_delegate_adj_modified (adj_delegate_t * ad)
 846 {
 847   ipsec_tun_protect_add_adj (ad->ad_adj_index,
 848                              ipsec_tun_protect_get (ad->ad_index));
 849 }
 850
 851 static void
 852 ipsec_tun_protect_adj_delegate_adj_created (adj_index_t ai)
 853 {
 854   /* add our delegate if there is protection for this neighbour */
 855   ip_address_t ip = IP_ADDRESS_V4_ALL_0S;
 856   ip_adjacency_t *adj;
 857   index_t itpi;
 858
 859   if (!adj_is_midchain (ai))
 860     return;
 861
 862   vec_validate_init_empty (ipsec_tun_protect_sa_by_adj_index, ai,
 863                            INDEX_INVALID);
 864
 865   adj = adj_get (ai);
 866
 867   ip_address_from_46 (&adj->sub_type.midchain.next_hop,
 868                       adj->ia_nh_proto, &ip);
 869
 870   itpi = ipsec_tun_protect_find (adj->rewrite_header.sw_if_index, &ip);
 871
 872   if (INDEX_INVALID != itpi)
 873     ipsec_tun_protect_adj_add (ai, ipsec_tun_protect_get (itpi));
 874 }
 875
 876 static u8 *
 877 ipsec_tun_protect_adj_delegate_format (const adj_delegate_t * aed, u8 * s)
 878 {
 879   const ipsec_tun_protect_t *itp;
 880
 881   itp = ipsec_tun_protect_from_const_base (aed);
 882   s = format (s, "ipsec-tun-protect:\n%U", format_ipsec_tun_protect, itp);
 883
 884   return (s);
 885 }
 886
 887 static void
 888 ipsec_tun_teib_entry_added (const teib_entry_t * ne)
 889 {
 890   ipsec_tun_protect_t *itp;
 891   index_t itpi;
 892
 893   itpi = ipsec_tun_protect_find (teib_entry_get_sw_if_index (ne),
 894                                  teib_entry_get_peer (ne));
 895
 896   if (INDEX_INVALID == itpi)
 897     return;
 898
 899   itp = ipsec_tun_protect_get (itpi);
 900   ipsec_tun_protect_rx_db_remove (&ipsec_main, itp);
 901   ipsec_tun_protect_update_from_teib (itp, ne);
 902   ipsec_tun_protect_set_crypto_addr (itp);
 903   ipsec_tun_protect_rx_db_add (&ipsec_main, itp);
 904
 905   ITP_DBG (itp, "teib-added");
 906 }
 907
 908 static void
 909 ipsec_tun_teib_entry_deleted (const teib_entry_t * ne)
 910 {
 911   ipsec_tun_protect_t *itp;
 912   index_t itpi;
 913
 914   itpi = ipsec_tun_protect_find (teib_entry_get_sw_if_index (ne),
 915                                  teib_entry_get_peer (ne));
 916
 917   if (INDEX_INVALID == itpi)
 918     return;
 919
 920   itp = ipsec_tun_protect_get (itpi);
 921   ipsec_tun_protect_rx_db_remove (&ipsec_main, itp);
 922   ipsec_tun_protect_update_from_teib (itp, NULL);
 923   ipsec_tun_protect_set_crypto_addr (itp);
 924
 925   ITP_DBG (itp, "teib-removed");
 926 }
 927
 928 /**
 929  * VFT registered with the adjacency delegate
 930  */
 931 const static adj_delegate_vft_t ipsec_tun_adj_delegate_vft = {
 932   .adv_adj_deleted = ipsec_tun_protect_adj_delegate_adj_deleted,
 933   .adv_adj_created = ipsec_tun_protect_adj_delegate_adj_created,
 934   .adv_adj_modified = ipsec_tun_protect_adj_delegate_adj_modified,
 935   .adv_format = ipsec_tun_protect_adj_delegate_format,
 936 };
 937
 938 const static teib_vft_t ipsec_tun_teib_vft = {
 939   .nv_added = ipsec_tun_teib_entry_added,
 940   .nv_deleted = ipsec_tun_teib_entry_deleted,
 941 };
 942
 943 void
 944 ipsec_tun_table_init (ip_address_family_t af, uword table_size, u32 n_buckets)
 945 {
 946   ipsec_main_t *im;
 947
 948   im = &ipsec_main;
 949
 950   if (AF_IP4 == af)
 951     clib_bihash_init_8_16 (&im->tun4_protect_by_key,
 952                            "IPSec IPv4 tunnels", n_buckets, table_size);
 953   else
 954     clib_bihash_init_24_16 (&im->tun6_protect_by_key,
 955                             "IPSec IPv6 tunnels", n_buckets, table_size);
 956 }
 957
 958 static clib_error_t *
 959 ipsec_tunnel_protect_init (vlib_main_t *vm)
 960 {
 961   ipsec_main_t *im;
 962
 963   im = &ipsec_main;
 964   clib_bihash_init_24_16 (&im->tun6_protect_by_key,
 965                           "IPSec IPv6 tunnels",
 966                           IPSEC_TUN_DEFAULT_HASH_NUM_BUCKETS,
 967                           IPSEC_TUN_DEFAULT_HASH_MEMORY_SIZE);
 968   clib_bihash_init_8_16 (&im->tun4_protect_by_key,
 969                          "IPSec IPv4 tunnels",
 970                          IPSEC_TUN_DEFAULT_HASH_NUM_BUCKETS,
 971                          IPSEC_TUN_DEFAULT_HASH_MEMORY_SIZE);
 972
 973   ipsec_tun_adj_delegate_type =
 974     adj_delegate_register_new_type (&ipsec_tun_adj_delegate_vft);
 975
 976   ipsec_tun_protect_logger = vlib_log_register_class ("ipsec", "tun");
 977
 978   teib_register (&ipsec_tun_teib_vft);
 979
 980   vnet_feature_register (ipsec_tun_feature_update, NULL);
 981
 982   return 0;
 983 }
 984
 985 VLIB_INIT_FUNCTION (ipsec_tunnel_protect_init);
 986
 987 /*
 988  * fd.io coding-style-patch-verification: ON
 989  *
 990  * Local Variables:
 991  * eval: (c-set-style "gnu")
 992  * End:
 993  */