src/vnet/ipsec/ipsec_if.c

   1 /*
   2  * ipsec_if.c : IPSec interface support
   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/vnet.h>
  19 #include <vnet/api_errno.h>
  20 #include <vnet/ip/ip.h>
  21 #include <vnet/fib/fib.h>
  22 #include <vnet/udp/udp.h>
  23 #include <vnet/adj/adj_midchain.h>
  24
  25 #include <vnet/ipsec/ipsec.h>
  26 #include <vnet/ipsec/esp.h>
  27
  28 void vl_api_rpc_call_main_thread (void *fp, u8 * data, u32 data_length);
  29
  30 static u8 *
  31 format_ipsec_name (u8 * s, va_list * args)
  32 {
  33   u32 dev_instance = va_arg (*args, u32);
  34   ipsec_main_t *im = &ipsec_main;
  35   ipsec_tunnel_if_t *t = im->tunnel_interfaces + dev_instance;
  36
  37   return format (s, "ipsec%d", t->show_instance);
  38 }
  39
  40 /* Statistics (not really errors) */
  41 #define foreach_ipsec_if_tx_error    \
  42 _(TX, "good packets transmitted")
  43
  44 static void
  45 ipsec_if_tunnel_stack (adj_index_t ai)
  46 {
  47   ipsec_main_t *ipm = &ipsec_main;
  48   ipsec_tunnel_if_t *it;
  49   ip_adjacency_t *adj;
  50   u32 sw_if_index;
  51
  52   adj = adj_get (ai);
  53   sw_if_index = adj->rewrite_header.sw_if_index;
  54
  55   if ((vec_len (ipm->ipsec_if_by_sw_if_index) <= sw_if_index) ||
  56       (~0 == ipm->ipsec_if_by_sw_if_index[sw_if_index]))
  57     return;
  58
  59   it = pool_elt_at_index (ipm->tunnel_interfaces,
  60                           ipm->ipsec_if_by_sw_if_index[sw_if_index]);
  61
  62   if (!vnet_hw_interface_is_link_up (vnet_get_main (), it->hw_if_index))
  63     {
  64       adj_midchain_delegate_unstack (ai);
  65     }
  66   else
  67     {
  68       ipsec_sa_t *sa;
  69
  70       sa = ipsec_sa_get (it->output_sa_index);
  71
  72       /* *INDENT-OFF* */
  73       fib_prefix_t pfx = {
  74         .fp_addr = sa->tunnel_dst_addr,
  75         .fp_len = (ipsec_sa_is_set_IS_TUNNEL_V6(sa) ? 128 : 32),
  76         .fp_proto = (ipsec_sa_is_set_IS_TUNNEL_V6(sa) ?
  77                      FIB_PROTOCOL_IP6 :
  78                      FIB_PROTOCOL_IP4),
  79       };
  80       /* *INDENT-ON* */
  81
  82       adj_midchain_delegate_stack (ai, sa->tx_fib_index, &pfx);
  83     }
  84 }
  85
  86 /**
  87  * @brief Call back when restacking all adjacencies on a IPSec interface
  88  */
  89 static adj_walk_rc_t
  90 ipsec_if_adj_walk_cb (adj_index_t ai, void *ctx)
  91 {
  92   ipsec_if_tunnel_stack (ai);
  93
  94   return (ADJ_WALK_RC_CONTINUE);
  95 }
  96
  97 static void
  98 ipsec_if_tunnel_restack (ipsec_tunnel_if_t * it)
  99 {
 100   fib_protocol_t proto;
 101
 102   /*
 103    * walk all the adjacencies on the IPSec interface and restack them
 104    */
 105   FOR_EACH_FIB_IP_PROTOCOL (proto)
 106   {
 107     adj_nbr_walk (it->sw_if_index, proto, ipsec_if_adj_walk_cb, NULL);
 108   }
 109 }
 110
 111 static clib_error_t *
 112 ipsec_admin_up_down_function (vnet_main_t * vnm, u32 hw_if_index, u32 flags)
 113 {
 114   ipsec_main_t *im = &ipsec_main;
 115   clib_error_t *err = 0;
 116   ipsec_tunnel_if_t *t;
 117   vnet_hw_interface_t *hi;
 118   ipsec_sa_t *sa;
 119
 120   hi = vnet_get_hw_interface (vnm, hw_if_index);
 121   t = pool_elt_at_index (im->tunnel_interfaces, hi->hw_instance);
 122   t->flags = flags;
 123
 124   if (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP)
 125     {
 126       sa = pool_elt_at_index (im->sad, t->input_sa_index);
 127
 128       err = ipsec_check_support_cb (im, sa);
 129       if (err)
 130         return err;
 131
 132       err = ipsec_add_del_sa_sess_cb (im, t->input_sa_index, 1);
 133       if (err)
 134         return err;
 135
 136       sa = pool_elt_at_index (im->sad, t->output_sa_index);
 137
 138       err = ipsec_check_support_cb (im, sa);
 139       if (err)
 140         return err;
 141
 142       err = ipsec_add_del_sa_sess_cb (im, t->output_sa_index, 1);
 143       if (err)
 144         return err;
 145
 146       vnet_hw_interface_set_flags (vnm, hw_if_index,
 147                                    VNET_HW_INTERFACE_FLAG_LINK_UP);
 148     }
 149   else
 150     {
 151       vnet_hw_interface_set_flags (vnm, hw_if_index, 0 /* down */ );
 152       sa = pool_elt_at_index (im->sad, t->input_sa_index);
 153       err = ipsec_add_del_sa_sess_cb (im, t->input_sa_index, 0);
 154       if (err)
 155         return err;
 156       sa = pool_elt_at_index (im->sad, t->output_sa_index);
 157       err = ipsec_add_del_sa_sess_cb (im, t->output_sa_index, 0);
 158       if (err)
 159         return err;
 160     }
 161
 162   ipsec_if_tunnel_restack (t);
 163
 164   return (NULL);
 165 }
 166
 167 static u8 *
 168 ipsec_if_build_rewrite (vnet_main_t * vnm,
 169                         u32 sw_if_index,
 170                         vnet_link_t link_type, const void *dst_address)
 171 {
 172   return (NULL);
 173 }
 174
 175 static void
 176 ipsec_if_update_adj (vnet_main_t * vnm, u32 sw_if_index, adj_index_t ai)
 177 {
 178   adj_nbr_midchain_update_rewrite
 179     (ai, NULL, NULL, ADJ_FLAG_MIDCHAIN_IP_STACK,
 180      ipsec_if_build_rewrite (vnm, sw_if_index, adj_get_link_type (ai), NULL));
 181
 182   ipsec_if_tunnel_stack (ai);
 183 }
 184
 185 /* *INDENT-OFF* */
 186 VNET_DEVICE_CLASS (ipsec_device_class) =
 187 {
 188   .name = "IPSec",
 189   .format_device_name = format_ipsec_name,
 190   .admin_up_down_function = ipsec_admin_up_down_function,
 191 };
 192 /* *INDENT-ON* */
 193
 194 /* *INDENT-OFF* */
 195 VNET_HW_INTERFACE_CLASS (ipsec_hw_class) =
 196 {
 197   .name = "IPSec",
 198   .build_rewrite = default_build_rewrite,
 199   .update_adjacency = ipsec_if_update_adj,
 200   .flags = VNET_HW_INTERFACE_CLASS_FLAG_P2P,
 201 };
 202 /* *INDENT-ON* */
 203
 204 static int
 205 ipsec_add_del_tunnel_if_rpc_callback (ipsec_add_del_tunnel_args_t * a)
 206 {
 207   vnet_main_t *vnm = vnet_get_main ();
 208   ASSERT (vlib_get_thread_index () == 0);
 209
 210   return ipsec_add_del_tunnel_if_internal (vnm, a, NULL);
 211 }
 212
 213 int
 214 ipsec_add_del_tunnel_if (ipsec_add_del_tunnel_args_t * args)
 215 {
 216   vl_api_rpc_call_main_thread (ipsec_add_del_tunnel_if_rpc_callback,
 217                                (u8 *) args, sizeof (*args));
 218   return 0;
 219 }
 220
 221 static u32
 222 ipsec_tun_mk_input_sa_id (u32 ti)
 223 {
 224   return (0x80000000 | ti);
 225 }
 226
 227 static u32
 228 ipsec_tun_mk_output_sa_id (u32 ti)
 229 {
 230   return (0xc0000000 | ti);
 231 }
 232
 233 static void
 234 ipsec_tunnel_feature_set (ipsec_main_t * im, ipsec_tunnel_if_t * t, u8 enable)
 235 {
 236   u8 arc;
 237
 238   arc = vnet_get_feature_arc_index ("ip4-output");
 239
 240   vnet_feature_enable_disable_with_index (arc,
 241                                           im->esp4_encrypt_tun_feature_index,
 242                                           t->sw_if_index, enable,
 243                                           &t->output_sa_index,
 244                                           sizeof (t->output_sa_index));
 245
 246   arc = vnet_get_feature_arc_index ("ip6-output");
 247
 248   vnet_feature_enable_disable_with_index (arc,
 249                                           im->esp6_encrypt_tun_feature_index,
 250                                           t->sw_if_index, enable,
 251                                           &t->output_sa_index,
 252                                           sizeof (t->output_sa_index));
 253 }
 254
 255 int
 256 ipsec_add_del_tunnel_if_internal (vnet_main_t * vnm,
 257                                   ipsec_add_del_tunnel_args_t * args,
 258                                   u32 * sw_if_index)
 259 {
 260   ipsec_tunnel_if_t *t;
 261   ipsec_main_t *im = &ipsec_main;
 262   vnet_hw_interface_t *hi = NULL;
 263   u32 hw_if_index = ~0;
 264   uword *p;
 265   u32 dev_instance;
 266   ipsec_key_t crypto_key, integ_key;
 267   ipsec_sa_flags_t flags;
 268   int rv;
 269   int is_ip6 = args->is_ip6;
 270   ipsec4_tunnel_key_t key4;
 271   ipsec6_tunnel_key_t key6;
 272
 273   if (!is_ip6)
 274     {
 275       key4.remote_ip = args->remote_ip.ip4.as_u32;
 276       key4.spi = clib_host_to_net_u32 (args->remote_spi);
 277       p = hash_get (im->ipsec4_if_pool_index_by_key, key4.as_u64);
 278     }
 279   else
 280     {
 281       key6.remote_ip = args->remote_ip.ip6;
 282       key6.spi = clib_host_to_net_u32 (args->remote_spi);
 283       p = hash_get_mem (im->ipsec6_if_pool_index_by_key, &key6);
 284     }
 285
 286   if (args->is_add)
 287     {
 288       /* check if same src/dst pair exists */
 289       if (p)
 290         return VNET_API_ERROR_INVALID_VALUE;
 291
 292       pool_get_aligned_zero (im->tunnel_interfaces, t, CLIB_CACHE_LINE_BYTES);
 293
 294       dev_instance = t - im->tunnel_interfaces;
 295       if (args->renumber)
 296         t->show_instance = args->show_instance;
 297       else
 298         t->show_instance = dev_instance;
 299
 300       if (hash_get (im->ipsec_if_real_dev_by_show_dev, t->show_instance))
 301         {
 302           pool_put (im->tunnel_interfaces, t);
 303           return VNET_API_ERROR_INSTANCE_IN_USE;
 304         }
 305
 306       hash_set (im->ipsec_if_real_dev_by_show_dev, t->show_instance,
 307                 dev_instance);
 308
 309       flags = IPSEC_SA_FLAG_IS_TUNNEL;
 310       if (args->is_ip6)
 311         flags |= IPSEC_SA_FLAG_IS_TUNNEL_V6;
 312       if (args->udp_encap)
 313         flags |= IPSEC_SA_FLAG_UDP_ENCAP;
 314       if (args->esn)
 315         flags |= IPSEC_SA_FLAG_USE_ESN;
 316       if (args->anti_replay)
 317         flags |= IPSEC_SA_FLAG_USE_ANTI_REPLAY;
 318
 319       ipsec_mk_key (&crypto_key,
 320                     args->remote_crypto_key, args->remote_crypto_key_len);
 321       ipsec_mk_key (&integ_key,
 322                     args->remote_integ_key, args->remote_integ_key_len);
 323
 324       rv = ipsec_sa_add (ipsec_tun_mk_input_sa_id (dev_instance),
 325                          args->remote_spi,
 326                          IPSEC_PROTOCOL_ESP,
 327                          args->crypto_alg,
 328                          &crypto_key,
 329                          args->integ_alg,
 330                          &integ_key,
 331                          (flags | IPSEC_SA_FLAG_IS_INBOUND),
 332                          args->tx_table_id,
 333                          args->salt,
 334                          &args->remote_ip,
 335                          &args->local_ip, &t->input_sa_index);
 336
 337       if (rv)
 338         return rv;
 339
 340       ipsec_mk_key (&crypto_key,
 341                     args->local_crypto_key, args->local_crypto_key_len);
 342       ipsec_mk_key (&integ_key,
 343                     args->local_integ_key, args->local_integ_key_len);
 344
 345       rv = ipsec_sa_add (ipsec_tun_mk_output_sa_id (dev_instance),
 346                          args->local_spi,
 347                          IPSEC_PROTOCOL_ESP,
 348                          args->crypto_alg,
 349                          &crypto_key,
 350                          args->integ_alg,
 351                          &integ_key,
 352                          flags,
 353                          args->tx_table_id,
 354                          args->salt,
 355                          &args->local_ip,
 356                          &args->remote_ip, &t->output_sa_index);
 357
 358       if (rv)
 359         return rv;
 360
 361       /* copy the key */
 362       if (is_ip6)
 363         hash_set_mem_alloc (&im->ipsec6_if_pool_index_by_key, &key6,
 364                             t - im->tunnel_interfaces);
 365       else
 366         hash_set (im->ipsec4_if_pool_index_by_key, key4.as_u64,
 367                   t - im->tunnel_interfaces);
 368
 369       hw_if_index = vnet_register_interface (vnm, ipsec_device_class.index,
 370                                              t - im->tunnel_interfaces,
 371                                              ipsec_hw_class.index,
 372                                              t - im->tunnel_interfaces);
 373
 374       hi = vnet_get_hw_interface (vnm, hw_if_index);
 375
 376       t->hw_if_index = hw_if_index;
 377       t->sw_if_index = hi->sw_if_index;
 378
 379       /* Standard default jumbo MTU. */
 380       vnet_sw_interface_set_mtu (vnm, t->sw_if_index, 9000);
 381
 382       /* Add the new tunnel to the DB of tunnels per sw_if_index ... */
 383       vec_validate_init_empty (im->ipsec_if_by_sw_if_index, t->sw_if_index,
 384                                ~0);
 385       im->ipsec_if_by_sw_if_index[t->sw_if_index] = dev_instance;
 386
 387       ipsec_tunnel_feature_set (im, t, 1);
 388
 389       /*1st interface, register protocol */
 390       if (pool_elts (im->tunnel_interfaces) == 1)
 391         {
 392           ip4_register_protocol (IP_PROTOCOL_IPSEC_ESP,
 393                                  ipsec4_if_input_node.index);
 394           ip6_register_protocol (IP_PROTOCOL_IPSEC_ESP,
 395                                  ipsec6_if_input_node.index);
 396         }
 397
 398     }
 399   else
 400     {
 401       u32 ti;
 402
 403       /* check if exists */
 404       if (!p)
 405         return VNET_API_ERROR_INVALID_VALUE;
 406
 407       ti = p[0];
 408       t = pool_elt_at_index (im->tunnel_interfaces, ti);
 409       hi = vnet_get_hw_interface (vnm, t->hw_if_index);
 410       vnet_sw_interface_set_flags (vnm, hi->sw_if_index, 0);    /* admin down */
 411
 412       ipsec_tunnel_feature_set (im, t, 0);
 413       vnet_delete_hw_interface (vnm, t->hw_if_index);
 414
 415       if (is_ip6)
 416         hash_unset_mem_free (&im->ipsec6_if_pool_index_by_key, &key6);
 417       else
 418         hash_unset (im->ipsec4_if_pool_index_by_key, key4.as_u64);
 419
 420       hash_unset (im->ipsec_if_real_dev_by_show_dev, t->show_instance);
 421       im->ipsec_if_by_sw_if_index[t->sw_if_index] = ~0;
 422
 423       pool_put (im->tunnel_interfaces, t);
 424
 425       /* delete input and output SA */
 426       ipsec_sa_del (ipsec_tun_mk_input_sa_id (ti));
 427       ipsec_sa_del (ipsec_tun_mk_output_sa_id (ti));
 428     }
 429
 430   if (sw_if_index)
 431     *sw_if_index = hi->sw_if_index;
 432
 433   return 0;
 434 }
 435
 436 int
 437 ipsec_set_interface_sa (vnet_main_t * vnm, u32 hw_if_index, u32 sa_id,
 438                         u8 is_outbound)
 439 {
 440   ipsec_main_t *im = &ipsec_main;
 441   vnet_hw_interface_t *hi;
 442   ipsec_tunnel_if_t *t;
 443   ipsec_sa_t *sa, *old_sa;
 444   u32 sa_index, old_sa_index;
 445   uword *p;
 446
 447   hi = vnet_get_hw_interface (vnm, hw_if_index);
 448   t = pool_elt_at_index (im->tunnel_interfaces, hi->dev_instance);
 449
 450   sa_index = ipsec_get_sa_index_by_sa_id (sa_id);
 451   if (sa_index == ~0)
 452     {
 453       clib_warning ("SA with ID %u not found", sa_id);
 454       return VNET_API_ERROR_INVALID_VALUE;
 455     }
 456
 457   if (ipsec_is_sa_used (sa_index))
 458     {
 459       clib_warning ("SA with ID %u is already in use", sa_id);
 460       return VNET_API_ERROR_INVALID_VALUE;
 461     }
 462
 463   sa = pool_elt_at_index (im->sad, sa_index);
 464
 465   if (!is_outbound)
 466     {
 467       old_sa_index = t->input_sa_index;
 468       old_sa = pool_elt_at_index (im->sad, old_sa_index);
 469
 470       if (ipsec_sa_is_set_IS_TUNNEL_V6 (sa) ^
 471           ipsec_sa_is_set_IS_TUNNEL_V6 (old_sa))
 472         {
 473           clib_warning ("IPsec interface SA endpoints type can't be changed");
 474           return VNET_API_ERROR_INVALID_VALUE;
 475         }
 476
 477       if (ipsec_sa_is_set_IS_TUNNEL_V6 (sa))
 478         {
 479           ipsec6_tunnel_key_t key;
 480
 481           /* unset old inbound hash entry. packets should stop arriving */
 482           key.remote_ip = old_sa->tunnel_src_addr.ip6;
 483           key.spi = clib_host_to_net_u32 (old_sa->spi);
 484
 485           p = hash_get_mem (im->ipsec6_if_pool_index_by_key, &key);
 486           if (p)
 487             hash_unset_mem_free (&im->ipsec6_if_pool_index_by_key, &key);
 488
 489           /* set new inbound SA, then set new hash entry */
 490           t->input_sa_index = sa_index;
 491           key.remote_ip = sa->tunnel_src_addr.ip6;
 492           key.spi = clib_host_to_net_u32 (sa->spi);
 493
 494           hash_set_mem_alloc (&im->ipsec6_if_pool_index_by_key, &key,
 495                               hi->dev_instance);
 496         }
 497       else
 498         {
 499           ipsec4_tunnel_key_t key;
 500
 501           /* unset old inbound hash entry. packets should stop arriving */
 502           key.remote_ip = old_sa->tunnel_src_addr.ip4.as_u32;
 503           key.spi = clib_host_to_net_u32 (old_sa->spi);
 504
 505           p = hash_get (im->ipsec4_if_pool_index_by_key, key.as_u64);
 506           if (p)
 507             hash_unset (im->ipsec4_if_pool_index_by_key, key.as_u64);
 508
 509           /* set new inbound SA, then set new hash entry */
 510           t->input_sa_index = sa_index;
 511           key.remote_ip = sa->tunnel_src_addr.ip4.as_u32;
 512           key.spi = clib_host_to_net_u32 (sa->spi);
 513
 514           hash_set (im->ipsec4_if_pool_index_by_key, key.as_u64,
 515                     hi->dev_instance);
 516         }
 517     }
 518   else
 519     {
 520       old_sa_index = t->output_sa_index;
 521       old_sa = pool_elt_at_index (im->sad, old_sa_index);
 522
 523       if (ipsec_sa_is_set_IS_TUNNEL_V6 (sa) ^
 524           ipsec_sa_is_set_IS_TUNNEL_V6 (old_sa))
 525         {
 526           clib_warning ("IPsec interface SA endpoints type can't be changed");
 527           return VNET_API_ERROR_INVALID_VALUE;
 528         }
 529
 530       /*
 531        * re-enable the feature to get the new SA in
 532        * the workers are stopped so no packets are sent in the clear
 533        */
 534       ipsec_tunnel_feature_set (im, t, 0);
 535       t->output_sa_index = sa_index;
 536       ipsec_tunnel_feature_set (im, t, 1);
 537     }
 538
 539   /* remove sa_id to sa_index mapping on old SA */
 540   if (ipsec_get_sa_index_by_sa_id (old_sa->id) == old_sa_index)
 541     hash_unset (im->sa_index_by_sa_id, old_sa->id);
 542
 543   if (ipsec_add_del_sa_sess_cb (im, old_sa_index, 0))
 544     {
 545       clib_warning ("IPsec backend add/del callback returned error");
 546       return VNET_API_ERROR_SYSCALL_ERROR_1;
 547     }
 548   ipsec_sa_del (old_sa->id);
 549
 550   return 0;
 551 }
 552
 553 clib_error_t *
 554 ipsec_tunnel_if_init (vlib_main_t * vm)
 555 {
 556   ipsec_main_t *im = &ipsec_main;
 557
 558   /* initialize the ipsec-if ip4 hash */
 559   im->ipsec4_if_pool_index_by_key =
 560     hash_create (0, sizeof (ipsec4_tunnel_key_t));
 561   /* initialize the ipsec-if ip6 hash */
 562   im->ipsec6_if_pool_index_by_key = hash_create_mem (0,
 563                                                      sizeof
 564                                                      (ipsec6_tunnel_key_t),
 565                                                      sizeof (uword));
 566   im->ipsec_if_real_dev_by_show_dev = hash_create (0, sizeof (uword));
 567
 568   udp_register_dst_port (vm, UDP_DST_PORT_ipsec, ipsec4_if_input_node.index,
 569                          1);
 570   return 0;
 571 }
 572
 573 VLIB_INIT_FUNCTION (ipsec_tunnel_if_init);
 574
 575
 576 /*
 577  * fd.io coding-style-patch-verification: ON
 578  *
 579  * Local Variables:
 580  * eval: (c-set-style "gnu")
 581  * End:
 582  */