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/esp.h>
  20 #include <vnet/udp/udp.h>
  21 #include <vnet/adj/adj_delegate.h>
  22 #include <vnet/teib/teib.h>
  23
  24 /**
  25  * The logger
  26  */
  27 vlib_log_class_t ipsec_tun_protect_logger;
  28
  29 /**
  30  * Pool of tunnel protection objects
  31  */
  32 ipsec_tun_protect_t *ipsec_tun_protect_pool;
  33
  34 /**
  35  * Adj delegate registered type
  36  */
  37 static adj_delegate_type_t ipsec_tun_adj_delegate_type;
  38
  39 /**
  40  * Adj index to TX SA mapping
  41  */
  42 index_t *ipsec_tun_protect_sa_by_adj_index;
  43
  44 const ip_address_t IP_ADDR_ALL_0 = IP_ADDRESS_V4_ALL_0S;
  45
  46 /**
  47  * The DB of all added per-nh tunnel protectiond
  48  */
  49 typedef struct ipsec_tun_protect_itf_db_t_
  50 {
  51   /** A hash table key'd on IP (4 or 6) address */
  52   uword *id_hash;
  53   /** If the interface is P2P then there is only one protect
  54    * object associated with the auto-adj for each NH proto */
  55   index_t id_itp;
  56 } ipsec_tun_protect_itf_db_t;
  57
  58 typedef struct ipsec_tun_protect_db_t_
  59 {
  60   /** Per-interface vector */
  61   ipsec_tun_protect_itf_db_t *id_itf;
  62 } ipsec_tun_protect_db_t;
  63
  64 static ipsec_tun_protect_db_t itp_db;
  65
  66 const static ipsec_tun_protect_itf_db_t IPSEC_TUN_PROTECT_DEFAULT_DB_ENTRY = {
  67   .id_itp = INDEX_INVALID,
  68 };
  69
  70 #define ITP_DBG(_itp, _fmt, _args...)                   \
  71 {                                                       \
  72   vlib_log_debug(ipsec_tun_protect_logger,              \
  73                  "[%U]: " _fmt,                         \
  74                  format_ipsec_tun_protect,              \
  75                  _itp, ##_args);                        \
  76 }
  77
  78 #define ITP_DBG2(_fmt, _args...)                        \
  79 {                                                       \
  80   vlib_log_debug(ipsec_tun_protect_logger,              \
  81                  _fmt, ##_args);                        \
  82 }
  83
  84 static u32 ipsec_tun_node_regs[N_AF];
  85
  86 void
  87 ipsec_tun_register_nodes (ip_address_family_t af)
  88 {
  89   if (0 == ipsec_tun_node_regs[af]++)
  90     {
  91       if (AF_IP4 == af)
  92         {
  93           udp_register_dst_port (vlib_get_main (),
  94                                  UDP_DST_PORT_ipsec,
  95                                  ipsec4_tun_input_node.index, 1);
  96           ip4_register_protocol (IP_PROTOCOL_IPSEC_ESP,
  97                                  ipsec4_tun_input_node.index);
  98         }
  99       else
 100         ip6_register_protocol (IP_PROTOCOL_IPSEC_ESP,
 101                                ipsec6_tun_input_node.index);
 102     }
 103 }
 104
 105 void
 106 ipsec_tun_unregister_nodes (ip_address_family_t af)
 107 {
 108   ASSERT (0 != ipsec_tun_node_regs[af]);
 109   if (0 == --ipsec_tun_node_regs[af])
 110     {
 111       if (AF_IP4 == af)
 112         {
 113           udp_unregister_dst_port (vlib_get_main (), UDP_DST_PORT_ipsec, 1);
 114           ip4_unregister_protocol (IP_PROTOCOL_IPSEC_ESP);
 115         }
 116       else
 117         ip6_unregister_protocol (IP_PROTOCOL_IPSEC_ESP);
 118     }
 119 }
 120
 121 static void
 122 ipsec_tun_protect_add_adj (adj_index_t ai, index_t sai)
 123 {
 124   vec_validate_init_empty (ipsec_tun_protect_sa_by_adj_index, ai,
 125                            INDEX_INVALID);
 126
 127   ipsec_tun_protect_sa_by_adj_index[ai] = sai;
 128 }
 129
 130 static inline const ipsec_tun_protect_t *
 131 ipsec_tun_protect_from_const_base (const adj_delegate_t * ad)
 132 {
 133   if (ad == NULL)
 134     return (NULL);
 135   return (pool_elt_at_index (ipsec_tun_protect_pool, ad->ad_index));
 136 }
 137
 138 static void
 139 ipsec_tun_protect_feature_set (ipsec_tun_protect_t * itp, u8 enable)
 140 {
 141   ITP_DBG2 ("%s on %U", (enable ? "enable" : "disable"),
 142             format_vnet_sw_if_index_name, vnet_get_main (),
 143             itp->itp_sw_if_index);
 144
 145   if (itp->itp_flags & IPSEC_PROTECT_L2)
 146     {
 147       /* l2-GRE only supported by the vnet ipsec code */
 148       vnet_feature_enable_disable ("ethernet-output",
 149                                    (ip46_address_is_ip4 (&itp->itp_tun.src) ?
 150                                     "esp4-encrypt-tun" :
 151                                     "esp6-encrypt-tun"),
 152                                    itp->itp_sw_if_index, enable, NULL, 0);
 153     }
 154   else
 155     {
 156       u32 fi4, fi6, sai;
 157       ipsec_main_t *im;
 158       ipsec_sa_t *sa;
 159
 160       im = &ipsec_main;
 161       sai = itp->itp_out_sa;
 162       sa = ipsec_sa_get (sai);
 163
 164       if (sa->crypto_alg == IPSEC_CRYPTO_ALG_NONE &&
 165           sa->integ_alg == IPSEC_INTEG_ALG_NONE)
 166         {
 167           fi4 = im->esp4_no_crypto_tun_feature_index;
 168           fi6 = im->esp6_no_crypto_tun_feature_index;
 169         }
 170       else
 171         {
 172           if (ip46_address_is_ip4 (&itp->itp_tun.src))
 173             {
 174               /* tunnel destination is v4 so we need the Xo4 indexes */
 175               fi4 = im->esp44_encrypt_tun_feature_index;
 176               fi6 = im->esp64_encrypt_tun_feature_index;
 177             }
 178           else
 179             {
 180               /* tunnel destination is v6 so we need the Xo6 indexes */
 181               fi4 = im->esp46_encrypt_tun_feature_index;
 182               fi6 = im->esp66_encrypt_tun_feature_index;
 183             }
 184         }
 185
 186       vnet_feature_enable_disable_with_index
 187         (vnet_get_feature_arc_index ("ip4-output"),
 188          fi4, itp->itp_sw_if_index, enable, NULL, 0);
 189       vnet_feature_enable_disable_with_index
 190         (vnet_get_feature_arc_index ("ip6-output"),
 191          fi6, itp->itp_sw_if_index, enable, NULL, 0);
 192     }
 193 }
 194
 195 static index_t
 196 ipsec_tun_protect_find (u32 sw_if_index, const ip_address_t * nh)
 197 {
 198   ipsec_tun_protect_itf_db_t *idi;
 199   uword *p;
 200
 201   if (vec_len (itp_db.id_itf) <= sw_if_index)
 202     return INDEX_INVALID;
 203
 204   if (vnet_sw_interface_is_p2p (vnet_get_main (), sw_if_index))
 205     return (itp_db.id_itf[sw_if_index].id_itp);
 206
 207   idi = &itp_db.id_itf[sw_if_index];
 208   p = hash_get_mem (idi->id_hash, nh);
 209
 210   if (NULL == p)
 211     {
 212       return INDEX_INVALID;
 213     }
 214   return (p[0]);
 215 }
 216
 217 static void
 218 ipsec_tun_protect_rx_db_add (ipsec_main_t * im,
 219                              const ipsec_tun_protect_t * itp)
 220 {
 221   const ipsec_sa_t *sa;
 222   u32 sai;
 223
 224   if (ip46_address_is_zero (&itp->itp_crypto.dst))
 225     return;
 226
 227   /* *INDENT-OFF* */
 228   FOR_EACH_IPSEC_PROTECT_INPUT_SAI(itp, sai,
 229   ({
 230       sa = ipsec_sa_get (sai);
 231
 232       ipsec_tun_lkup_result_t res = {
 233         .tun_index = itp - ipsec_tun_protect_pool,
 234         .sa_index = sai,
 235       };
 236
 237       /*
 238        * The key is formed from the tunnel's destination
 239        * as the packet lookup is done from the packet's source
 240        */
 241       if (ip46_address_is_ip4 (&itp->itp_crypto.dst))
 242         {
 243           ipsec4_tunnel_key_t key = {
 244             .remote_ip = itp->itp_crypto.dst.ip4,
 245             .spi = clib_host_to_net_u32 (sa->spi),
 246           };
 247           hash_set (im->tun4_protect_by_key, key.as_u64, res.as_u64);
 248           ipsec_tun_register_nodes(AF_IP4);
 249         }
 250       else
 251         {
 252           ipsec6_tunnel_key_t key = {
 253             .remote_ip = itp->itp_crypto.dst.ip6,
 254             .spi = clib_host_to_net_u32 (sa->spi),
 255           };
 256           hash_set_mem_alloc (&im->tun6_protect_by_key, &key, res.as_u64);
 257           ipsec_tun_register_nodes(AF_IP6);
 258         }
 259   }))
 260   /* *INDENT-ON* */
 261 }
 262
 263 static adj_walk_rc_t
 264 ipsec_tun_protect_adj_add (adj_index_t ai, void *arg)
 265 {
 266   ipsec_tun_protect_t *itp = arg;
 267   adj_delegate_add (adj_get (ai), ipsec_tun_adj_delegate_type,
 268                     itp - ipsec_tun_protect_pool);
 269   ipsec_tun_protect_add_adj (ai, itp->itp_out_sa);
 270
 271   return (ADJ_WALK_RC_CONTINUE);
 272 }
 273
 274 static void
 275 ipsec_tun_protect_tx_db_add (ipsec_tun_protect_t * itp)
 276 {
 277   /*
 278    * add the delegate to the adj
 279    */
 280   ipsec_tun_protect_itf_db_t *idi;
 281   fib_protocol_t nh_proto;
 282   ip46_address_t nh;
 283
 284   vec_validate_init_empty (itp_db.id_itf,
 285                            itp->itp_sw_if_index,
 286                            IPSEC_TUN_PROTECT_DEFAULT_DB_ENTRY);
 287
 288   idi = &itp_db.id_itf[itp->itp_sw_if_index];
 289
 290   if (vnet_sw_interface_is_p2p (vnet_get_main (), itp->itp_sw_if_index))
 291     {
 292       if (INDEX_INVALID == idi->id_itp)
 293         {
 294           ipsec_tun_protect_feature_set (itp, 1);
 295         }
 296       idi->id_itp = itp - ipsec_tun_protect_pool;
 297
 298       FOR_EACH_FIB_IP_PROTOCOL (nh_proto)
 299         adj_nbr_walk (itp->itp_sw_if_index,
 300                       nh_proto, ipsec_tun_protect_adj_add, itp);
 301     }
 302   else
 303     {
 304       if (NULL == idi->id_hash)
 305         {
 306           idi->id_hash =
 307             hash_create_mem (0, sizeof (ip_address_t), sizeof (uword));
 308           /*
 309            * enable the encrypt feature for egress if this is the first addition
 310            * on this interface
 311            */
 312           ipsec_tun_protect_feature_set (itp, 1);
 313         }
 314
 315       hash_set_mem (idi->id_hash, itp->itp_key, itp - ipsec_tun_protect_pool);
 316
 317       /*
 318        * walk all the adjs with the same nh on this interface
 319        * to associate them with this protection
 320        */
 321       nh_proto = ip_address_to_46 (itp->itp_key, &nh);
 322
 323       adj_nbr_walk_nh (itp->itp_sw_if_index,
 324                        nh_proto, &nh, ipsec_tun_protect_adj_add, itp);
 325
 326       ipsec_tun_register_nodes (FIB_PROTOCOL_IP6 == nh_proto ?
 327                                 AF_IP6 : AF_IP4);
 328     }
 329 }
 330
 331 static void
 332 ipsec_tun_protect_rx_db_remove (ipsec_main_t * im,
 333                                 const ipsec_tun_protect_t * itp)
 334 {
 335   const ipsec_sa_t *sa;
 336
 337   /* *INDENT-OFF* */
 338   FOR_EACH_IPSEC_PROTECT_INPUT_SA(itp, sa,
 339   ({
 340       if (ip46_address_is_ip4 (&itp->itp_crypto.dst))
 341         {
 342           ipsec4_tunnel_key_t key = {
 343             .remote_ip = itp->itp_crypto.dst.ip4,
 344             .spi = clib_host_to_net_u32 (sa->spi),
 345           };
 346           if (hash_get(im->tun4_protect_by_key, key.as_u64))
 347             {
 348               hash_unset (im->tun4_protect_by_key, key.as_u64);
 349               ipsec_tun_unregister_nodes(AF_IP4);
 350             }
 351         }
 352       else
 353         {
 354           ipsec6_tunnel_key_t key = {
 355             .remote_ip = itp->itp_crypto.dst.ip6,
 356             .spi = clib_host_to_net_u32 (sa->spi),
 357           };
 358           if (hash_get_mem(im->tun6_protect_by_key, &key))
 359             {
 360               hash_unset_mem_free (&im->tun6_protect_by_key, &key);
 361               ipsec_tun_unregister_nodes(AF_IP6);
 362             }
 363         }
 364   }))
 365   /* *INDENT-ON* */
 366 }
 367
 368 static adj_walk_rc_t
 369 ipsec_tun_protect_adj_remove (adj_index_t ai, void *arg)
 370 {
 371   adj_delegate_remove (ai, ipsec_tun_adj_delegate_type);
 372   ipsec_tun_protect_add_adj (ai, INDEX_INVALID);
 373
 374   return (ADJ_WALK_RC_CONTINUE);
 375 }
 376
 377 static void
 378 ipsec_tun_protect_tx_db_remove (ipsec_tun_protect_t * itp)
 379 {
 380   ipsec_tun_protect_itf_db_t *idi;
 381   fib_protocol_t nh_proto;
 382   ip46_address_t nh;
 383
 384   nh_proto = ip_address_to_46 (itp->itp_key, &nh);
 385   idi = &itp_db.id_itf[itp->itp_sw_if_index];
 386
 387   if (vnet_sw_interface_is_p2p (vnet_get_main (), itp->itp_sw_if_index))
 388     {
 389       ipsec_tun_protect_feature_set (itp, 0);
 390       idi->id_itp = INDEX_INVALID;
 391
 392       FOR_EACH_FIB_IP_PROTOCOL (nh_proto)
 393         adj_nbr_walk (itp->itp_sw_if_index,
 394                       nh_proto, ipsec_tun_protect_adj_remove, itp);
 395     }
 396   else
 397     {
 398       adj_nbr_walk_nh (itp->itp_sw_if_index,
 399                        nh_proto, &nh, ipsec_tun_protect_adj_remove, itp);
 400
 401       hash_unset_mem (idi->id_hash, itp->itp_key);
 402
 403       if (0 == hash_elts (idi->id_hash))
 404         {
 405           ipsec_tun_protect_feature_set (itp, 0);
 406           hash_free (idi->id_hash);
 407           idi->id_hash = NULL;
 408         }
 409       ipsec_tun_unregister_nodes (FIB_PROTOCOL_IP6 == nh_proto ?
 410                                   AF_IP6 : AF_IP4);
 411     }
 412 }
 413
 414 static void
 415 ipsec_tun_protect_set_crypto_addr (ipsec_tun_protect_t * itp)
 416 {
 417   ipsec_sa_t *sa;
 418
 419   /* *INDENT-OFF* */
 420   FOR_EACH_IPSEC_PROTECT_INPUT_SA(itp, sa,
 421   ({
 422     if (ipsec_sa_is_set_IS_TUNNEL (sa))
 423       {
 424         itp->itp_crypto.src = sa->tunnel_dst_addr;
 425         itp->itp_crypto.dst = sa->tunnel_src_addr;
 426         ipsec_sa_set_IS_PROTECT (sa);
 427         itp->itp_flags |= IPSEC_PROTECT_ENCAPED;
 428       }
 429     else
 430       {
 431         itp->itp_crypto.src = itp->itp_tun.src;
 432         itp->itp_crypto.dst = itp->itp_tun.dst;
 433         itp->itp_flags &= ~IPSEC_PROTECT_ENCAPED;
 434       }
 435   }));
 436   /* *INDENT-ON* */
 437 }
 438
 439 static void
 440 ipsec_tun_protect_config (ipsec_main_t * im,
 441                           ipsec_tun_protect_t * itp, u32 sa_out, u32 * sas_in)
 442 {
 443   index_t sai;
 444   u32 ii;
 445
 446   itp->itp_n_sa_in = vec_len (sas_in);
 447   for (ii = 0; ii < itp->itp_n_sa_in; ii++)
 448     itp->itp_in_sas[ii] = sas_in[ii];
 449   itp->itp_out_sa = sa_out;
 450
 451   ipsec_sa_lock (itp->itp_out_sa);
 452
 453   /* *INDENT-OFF* */
 454   FOR_EACH_IPSEC_PROTECT_INPUT_SAI(itp, sai,
 455   ({
 456     ipsec_sa_lock(sai);
 457   }));
 458   ipsec_tun_protect_set_crypto_addr(itp);
 459   /* *INDENT-ON* */
 460
 461   /*
 462    * add to the DB against each SA
 463    */
 464   ipsec_tun_protect_rx_db_add (im, itp);
 465   ipsec_tun_protect_tx_db_add (itp);
 466
 467   ITP_DBG (itp, "configured");
 468 }
 469
 470 static void
 471 ipsec_tun_protect_unconfig (ipsec_main_t * im, ipsec_tun_protect_t * itp)
 472 {
 473   ipsec_sa_t *sa;
 474   index_t sai;
 475
 476   /* *INDENT-OFF* */
 477   FOR_EACH_IPSEC_PROTECT_INPUT_SA(itp, sa,
 478   ({
 479     ipsec_sa_unset_IS_PROTECT (sa);
 480   }));
 481
 482   ipsec_tun_protect_rx_db_remove (im, itp);
 483   ipsec_tun_protect_tx_db_remove (itp);
 484
 485   ipsec_sa_unlock(itp->itp_out_sa);
 486
 487   FOR_EACH_IPSEC_PROTECT_INPUT_SAI(itp, sai,
 488   ({
 489     ipsec_sa_unlock(sai);
 490   }));
 491   /* *INDENT-ON* */
 492   ITP_DBG (itp, "unconfigured");
 493 }
 494
 495 int
 496 ipsec_tun_protect_update_one (u32 sw_if_index,
 497                               const ip_address_t * nh, u32 sa_out, u32 sa_in)
 498 {
 499   u32 *sas_in = NULL;
 500   int rv;
 501
 502   vec_add1 (sas_in, sa_in);
 503   rv = ipsec_tun_protect_update (sw_if_index, nh, sa_out, sas_in);
 504
 505   return (rv);
 506 }
 507
 508 int
 509 ipsec_tun_protect_update_out (u32 sw_if_index,
 510                               const ip_address_t * nh, u32 sa_out)
 511 {
 512   u32 itpi, *sas_in, sai, *saip;
 513   ipsec_tun_protect_t *itp;
 514   ipsec_main_t *im;
 515   int rv;
 516
 517   sas_in = NULL;
 518   rv = 0;
 519   im = &ipsec_main;
 520
 521   itpi = ipsec_tun_protect_find (sw_if_index, nh);
 522
 523   if (INDEX_INVALID == itpi)
 524     {
 525       return (VNET_API_ERROR_INVALID_INTERFACE);
 526     }
 527
 528   itp = pool_elt_at_index (ipsec_tun_protect_pool, itpi);
 529
 530   /* *INDENT-OFF* */
 531   FOR_EACH_IPSEC_PROTECT_INPUT_SAI (itp, sai,
 532   ({
 533     ipsec_sa_lock (sai);
 534     vec_add1 (sas_in, sai);
 535   }));
 536   /* *INDENT-ON* */
 537
 538   sa_out = ipsec_sa_find_and_lock (sa_out);
 539
 540   if (~0 == sa_out)
 541     {
 542       rv = VNET_API_ERROR_INVALID_VALUE;
 543       goto out;
 544     }
 545
 546   ipsec_tun_protect_unconfig (im, itp);
 547   ipsec_tun_protect_config (im, itp, sa_out, sas_in);
 548
 549   ipsec_sa_unlock (sa_out);
 550   vec_foreach (saip, sas_in) ipsec_sa_unlock (*saip);
 551
 552 out:
 553   vec_free (sas_in);
 554   return (rv);
 555 }
 556
 557 int
 558 ipsec_tun_protect_update_in (u32 sw_if_index,
 559                              const ip_address_t * nh, u32 sa_in)
 560 {
 561   u32 itpi, *sas_in, sa_out;
 562   ipsec_tun_protect_t *itp;
 563   ipsec_main_t *im;
 564   int rv;
 565
 566   sas_in = NULL;
 567   rv = 0;
 568   im = &ipsec_main;
 569   itpi = ipsec_tun_protect_find (sw_if_index, nh);
 570
 571   if (INDEX_INVALID == itpi)
 572     {
 573       return (VNET_API_ERROR_INVALID_INTERFACE);
 574     }
 575
 576   sa_in = ipsec_sa_find_and_lock (sa_in);
 577
 578   if (~0 == sa_in)
 579     {
 580       rv = VNET_API_ERROR_INVALID_VALUE;
 581       goto out;
 582     }
 583   vec_add1 (sas_in, sa_in);
 584
 585   itp = pool_elt_at_index (ipsec_tun_protect_pool, itpi);
 586   sa_out = itp->itp_out_sa;
 587
 588   ipsec_sa_lock (sa_out);
 589
 590   ipsec_tun_protect_unconfig (im, itp);
 591   ipsec_tun_protect_config (im, itp, sa_out, sas_in);
 592
 593   ipsec_sa_unlock (sa_out);
 594   ipsec_sa_unlock (sa_in);
 595 out:
 596   vec_free (sas_in);
 597   return (rv);
 598 }
 599
 600 static void
 601 ipsec_tun_protect_update_from_teib (ipsec_tun_protect_t * itp,
 602                                     const teib_entry_t * ne)
 603 {
 604   if (NULL != ne)
 605     {
 606       const fib_prefix_t *pfx;
 607
 608       pfx = teib_entry_get_nh (ne);
 609
 610       ip46_address_copy (&itp->itp_tun.dst, &pfx->fp_addr);
 611     }
 612   else
 613     ip46_address_reset (&itp->itp_tun.dst);
 614 }
 615
 616 int
 617 ipsec_tun_protect_update (u32 sw_if_index,
 618                           const ip_address_t * nh, u32 sa_out, u32 * sas_in)
 619 {
 620   ipsec_tun_protect_t *itp;
 621   u32 itpi, ii, *saip;
 622   ipsec_main_t *im;
 623   int rv;
 624
 625   ITP_DBG2 ("update: %U/%U",
 626             format_vnet_sw_if_index_name, vnet_get_main (), sw_if_index,
 627             format_ip_address, nh);
 628
 629   if (vec_len (sas_in) > ITP_MAX_N_SA_IN)
 630     {
 631       rv = VNET_API_ERROR_LIMIT_EXCEEDED;
 632       goto out;
 633     }
 634
 635   rv = 0;
 636   im = &ipsec_main;
 637   if (NULL == nh)
 638     nh = &IP_ADDR_ALL_0;
 639   itpi = ipsec_tun_protect_find (sw_if_index, nh);
 640
 641   vec_foreach_index (ii, sas_in)
 642   {
 643     sas_in[ii] = ipsec_sa_find_and_lock (sas_in[ii]);
 644     if (~0 == sas_in[ii])
 645       {
 646         rv = VNET_API_ERROR_INVALID_VALUE;
 647         goto out;
 648       }
 649   }
 650
 651   sa_out = ipsec_sa_find_and_lock (sa_out);
 652
 653   if (~0 == sa_out)
 654     {
 655       rv = VNET_API_ERROR_INVALID_VALUE;
 656       goto out;
 657     }
 658
 659   if (INDEX_INVALID == itpi)
 660     {
 661       vnet_device_class_t *dev_class;
 662       vnet_hw_interface_t *hi;
 663       vnet_main_t *vnm;
 664       u8 is_l2;
 665
 666       vnm = vnet_get_main ();
 667       hi = vnet_get_sup_hw_interface (vnm, sw_if_index);
 668       dev_class = vnet_get_device_class (vnm, hi->dev_class_index);
 669
 670       if (NULL == dev_class->ip_tun_desc)
 671         {
 672           rv = VNET_API_ERROR_INVALID_SW_IF_INDEX;
 673           goto out;
 674         }
 675
 676       pool_get_zero (ipsec_tun_protect_pool, itp);
 677
 678       itp->itp_sw_if_index = sw_if_index;
 679
 680       itp->itp_n_sa_in = vec_len (sas_in);
 681       for (ii = 0; ii < itp->itp_n_sa_in; ii++)
 682         itp->itp_in_sas[ii] = sas_in[ii];
 683       itp->itp_out_sa = sa_out;
 684
 685       itp->itp_key = clib_mem_alloc (sizeof (*itp->itp_key));
 686       ip_address_copy (itp->itp_key, nh);
 687
 688       rv = dev_class->ip_tun_desc (sw_if_index,
 689                                    &itp->itp_tun.src,
 690                                    &itp->itp_tun.dst, &is_l2);
 691
 692       if (rv)
 693         goto out;
 694
 695       if (ip46_address_is_zero (&itp->itp_tun.dst))
 696         {
 697           /* tunnel has no destination address, presumably because it's p2mp
 698              in which case we use the nh that this is protection for */
 699           ip46_address_t peer;
 700
 701           ip_address_to_46 (nh, &peer);
 702
 703           ipsec_tun_protect_update_from_teib
 704             (itp, teib_entry_find (sw_if_index, &peer));
 705         }
 706
 707       if (is_l2)
 708         itp->itp_flags |= IPSEC_PROTECT_L2;
 709
 710       /*
 711        * add to the tunnel DB for ingress
 712        *  - if the SA is in trasnport mode, then the packates will arrivw
 713        *    with the IP src,dst of the protected tunnel, in which case we can
 714        *    simply strip the IP header and hand the payload to the protocol
 715        *    appropriate input handler
 716        *  - if the SA is in tunnel mode then there are two IP headers present
 717        *    one for the crytpo tunnel endpoints (described in the SA) and one
 718        *    for the tunnel endpoints. The outer IP headers in the srriving
 719        *    packets will have the crypto endpoints. So the DB needs to contain
 720        *    the crpto endpoint. Once the crypto header is stripped, revealing,
 721        *    the tunnel-IP we have 2 choices:
 722        *     1) do a tunnel lookup based on the revealed header
 723        *     2) skip the tunnel lookup and assume that the packet matches the
 724        *        one that is protected here.
 725        *    If we did 1) then we would allow our peer to use the SA for tunnel
 726        *    X to inject traffic onto tunnel Y, this is not good. If we do 2)
 727        *    then we don't verify that the peer is indeed using SA for tunnel
 728        *    X and addressing tunnel X. So we take a compromise, once the SA
 729        *    matches to tunnel X we veriy that the inner IP matches the value
 730        *    of the tunnel we are protecting, else it's dropped.
 731        */
 732       ipsec_tun_protect_config (im, itp, sa_out, sas_in);
 733     }
 734   else
 735     {
 736       /* updating SAs only */
 737       itp = pool_elt_at_index (ipsec_tun_protect_pool, itpi);
 738
 739       ipsec_tun_protect_unconfig (im, itp);
 740       ipsec_tun_protect_config (im, itp, sa_out, sas_in);
 741     }
 742
 743   ipsec_sa_unlock (sa_out);
 744   vec_foreach (saip, sas_in) ipsec_sa_unlock (*saip);
 745   vec_free (sas_in);
 746
 747 out:
 748   return (rv);
 749 }
 750
 751 int
 752 ipsec_tun_protect_del (u32 sw_if_index, const ip_address_t * nh)
 753 {
 754   ipsec_tun_protect_t *itp;
 755   ipsec_main_t *im;
 756   index_t itpi;
 757
 758   ITP_DBG2 ("delete: %U/%U",
 759             format_vnet_sw_if_index_name, vnet_get_main (), sw_if_index,
 760             format_ip_address, nh);
 761
 762   im = &ipsec_main;
 763   if (NULL == nh)
 764     nh = &IP_ADDR_ALL_0;
 765
 766   itpi = ipsec_tun_protect_find (sw_if_index, nh);
 767
 768   if (INDEX_INVALID == itpi)
 769     return (VNET_API_ERROR_NO_SUCH_ENTRY);
 770
 771   itp = ipsec_tun_protect_get (itpi);
 772   ipsec_tun_protect_unconfig (im, itp);
 773
 774   clib_mem_free (itp->itp_key);
 775   pool_put (ipsec_tun_protect_pool, itp);
 776
 777   return (0);
 778 }
 779
 780 void
 781 ipsec_tun_protect_walk (ipsec_tun_protect_walk_cb_t fn, void *ctx)
 782 {
 783   index_t itpi;
 784
 785   /* *INDENT-OFF* */
 786   pool_foreach_index(itpi, ipsec_tun_protect_pool,
 787   ({
 788     fn (itpi, ctx);
 789   }));
 790   /* *INDENT-ON* */
 791 }
 792
 793 void
 794 ipsec_tun_protect_walk_itf (u32 sw_if_index,
 795                             ipsec_tun_protect_walk_cb_t fn, void *ctx)
 796 {
 797   ipsec_tun_protect_itf_db_t *idi;
 798   ip_address_t *key;
 799   index_t itpi;
 800
 801   if (vec_len (itp_db.id_itf) <= sw_if_index)
 802     return;
 803
 804   idi = &itp_db.id_itf[sw_if_index];
 805
 806   /* *INDENT-OFF* */
 807   hash_foreach(key, itpi, idi->id_hash,
 808   ({
 809     fn (itpi, ctx);
 810   }));
 811   /* *INDENT-ON* */
 812   if (INDEX_INVALID != idi->id_itp)
 813     fn (idi->id_itp, ctx);
 814 }
 815
 816 static void
 817 ipsec_tun_protect_adj_delegate_adj_deleted (adj_delegate_t * ad)
 818 {
 819   /* remove our delegate */
 820   adj_delegate_remove (ad->ad_adj_index, ipsec_tun_adj_delegate_type);
 821   ipsec_tun_protect_add_adj (ad->ad_adj_index, INDEX_INVALID);
 822 }
 823
 824 static void
 825 ipsec_tun_protect_adj_delegate_adj_created (adj_index_t ai)
 826 {
 827   /* add our delegate if there is protection for this neighbour */
 828   ip_address_t ip = IP_ADDRESS_V4_ALL_0S;
 829   ip_adjacency_t *adj;
 830   index_t itpi;
 831
 832   adj = adj_get (ai);
 833
 834   if (adj->lookup_next_index != IP_LOOKUP_NEXT_MIDCHAIN)
 835     return;
 836
 837   ip_address_from_46 (&adj->sub_type.midchain.next_hop,
 838                       adj->ia_nh_proto, &ip);
 839
 840   itpi = ipsec_tun_protect_find (adj->rewrite_header.sw_if_index, &ip);
 841
 842   if (INDEX_INVALID != itpi)
 843     {
 844       const ipsec_tun_protect_t *itp;
 845
 846       itp = ipsec_tun_protect_get (itpi);
 847       adj_delegate_add (adj_get (ai), ipsec_tun_adj_delegate_type, itpi);
 848       ipsec_tun_protect_add_adj (ai, itp->itp_out_sa);
 849     }
 850 }
 851
 852 static u8 *
 853 ipsec_tun_protect_adj_delegate_format (const adj_delegate_t * aed, u8 * s)
 854 {
 855   const ipsec_tun_protect_t *itp;
 856
 857   itp = ipsec_tun_protect_from_const_base (aed);
 858   s = format (s, "ipsec-tun-protect:\n%U", format_ipsec_tun_protect, itp);
 859
 860   return (s);
 861 }
 862
 863 static void
 864 ipsec_tun_teib_entry_added (const teib_entry_t * ne)
 865 {
 866   const ip46_address_t *peer46;
 867   ipsec_tun_protect_t *itp;
 868   ip_address_t peer;
 869   index_t itpi;
 870
 871   peer46 = teib_entry_get_peer (ne);
 872   ip_address_from_46 (peer46,
 873                       (ip46_address_is_ip4 (peer46) ?
 874                        FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6), &peer);
 875
 876   itpi = ipsec_tun_protect_find (teib_entry_get_sw_if_index (ne), &peer);
 877
 878   if (INDEX_INVALID == itpi)
 879     return;
 880
 881   itp = ipsec_tun_protect_get (itpi);
 882   ipsec_tun_protect_rx_db_remove (&ipsec_main, itp);
 883   ipsec_tun_protect_update_from_teib (itp, ne);
 884   ipsec_tun_protect_set_crypto_addr (itp);
 885   ipsec_tun_protect_rx_db_add (&ipsec_main, itp);
 886
 887   ITP_DBG (itp, "teib-added");
 888 }
 889
 890 static void
 891 ipsec_tun_teib_entry_deleted (const teib_entry_t * ne)
 892 {
 893   const ip46_address_t *peer46;
 894   ipsec_tun_protect_t *itp;
 895   ip_address_t peer;
 896   index_t itpi;
 897
 898   peer46 = teib_entry_get_peer (ne);
 899   ip_address_from_46 (peer46,
 900                       (ip46_address_is_ip4 (peer46) ?
 901                        FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6), &peer);
 902
 903   itpi = ipsec_tun_protect_find (teib_entry_get_sw_if_index (ne), &peer);
 904
 905   if (INDEX_INVALID == itpi)
 906     return;
 907
 908   itp = ipsec_tun_protect_get (itpi);
 909   ipsec_tun_protect_rx_db_remove (&ipsec_main, itp);
 910   ipsec_tun_protect_update_from_teib (itp, NULL);
 911   ipsec_tun_protect_set_crypto_addr (itp);
 912
 913   ITP_DBG (itp, "teib-removed");
 914 }
 915
 916 /**
 917  * VFT registered with the adjacency delegate
 918  */
 919 const static adj_delegate_vft_t ipsec_tun_adj_delegate_vft = {
 920   .adv_adj_deleted = ipsec_tun_protect_adj_delegate_adj_deleted,
 921   .adv_adj_created = ipsec_tun_protect_adj_delegate_adj_created,
 922   .adv_format = ipsec_tun_protect_adj_delegate_format,
 923 };
 924
 925 const static teib_vft_t ipsec_tun_teib_vft = {
 926   .nv_added = ipsec_tun_teib_entry_added,
 927   .nv_deleted = ipsec_tun_teib_entry_deleted,
 928 };
 929
 930 clib_error_t *
 931 ipsec_tunnel_protect_init (vlib_main_t * vm)
 932 {
 933   ipsec_main_t *im;
 934
 935   im = &ipsec_main;
 936   im->tun6_protect_by_key = hash_create_mem (0,
 937                                              sizeof (ipsec6_tunnel_key_t),
 938                                              sizeof (u64));
 939   im->tun4_protect_by_key = hash_create (0, sizeof (u64));
 940
 941   /* set up feature nodes to drop outbound packets with no crypto alg set */
 942   ipsec_add_feature ("ip4-output", "esp4-no-crypto",
 943                      &im->esp4_no_crypto_tun_feature_index);
 944   ipsec_add_feature ("ip6-output", "esp6-no-crypto",
 945                      &im->esp6_no_crypto_tun_feature_index);
 946
 947   ipsec_tun_adj_delegate_type =
 948     adj_delegate_register_new_type (&ipsec_tun_adj_delegate_vft);
 949
 950   ipsec_tun_protect_logger = vlib_log_register_class ("ipsec", "tun");
 951
 952   teib_register (&ipsec_tun_teib_vft);
 953
 954   return 0;
 955 }
 956
 957 VLIB_INIT_FUNCTION (ipsec_tunnel_protect_init);
 958
 959
 960 /*
 961  * fd.io coding-style-patch-verification: ON
 962  *
 963  * Local Variables:
 964  * eval: (c-set-style "gnu")
 965  * End:
 966  */