src/vnet/ipsec/ipsec_input.c

   1 /*
   2  * decap.c : IPSec tunnel decapsulation
   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/feature/feature.h>
  22
  23 #include <vnet/ipsec/ipsec.h>
  24 #include <vnet/ipsec/esp.h>
  25 #include <vnet/ipsec/ah.h>
  26 #include <vnet/ipsec/ipsec_io.h>
  27
  28 #define foreach_ipsec_input_error               \
  29 _(RX_PKTS, "IPSEC pkts received")               \
  30 _(RX_MATCH_PKTS, "IPSEC pkts matched")
  31
  32 typedef enum
  33 {
  34 #define _(sym,str) IPSEC_INPUT_ERROR_##sym,
  35   foreach_ipsec_input_error
  36 #undef _
  37     IPSEC_INPUT_N_ERROR,
  38 } ipsec_input_error_t;
  39
  40 static char *ipsec_input_error_strings[] = {
  41 #define _(sym,string) string,
  42   foreach_ipsec_input_error
  43 #undef _
  44 };
  45
  46 typedef struct
  47 {
  48   ip_protocol_t proto;
  49   u32 spd;
  50   u32 policy_index;
  51   u32 sa_id;
  52   u32 spi;
  53   u32 seq;
  54 } ipsec_input_trace_t;
  55
  56 /* packet trace format function */
  57 static u8 *
  58 format_ipsec_input_trace (u8 * s, va_list * args)
  59 {
  60   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  61   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  62   ipsec_input_trace_t *t = va_arg (*args, ipsec_input_trace_t *);
  63
  64   s = format (s, "%U: sa_id %u spd %u policy %d spi %u (0x%08x) seq %u",
  65               format_ip_protocol, t->proto, t->sa_id,
  66               t->spd, t->policy_index, t->spi, t->spi, t->seq);
  67
  68   return s;
  69 }
  70
  71 always_inline ipsec_policy_t *
  72 ipsec_input_protect_policy_match (ipsec_spd_t * spd, u32 sa, u32 da, u32 spi)
  73 {
  74   ipsec_main_t *im = &ipsec_main;
  75   ipsec_policy_t *p;
  76   ipsec_sa_t *s;
  77   u32 *i;
  78
  79   vec_foreach (i, spd->policies[IPSEC_SPD_POLICY_IP4_INBOUND_PROTECT])
  80   {
  81     p = pool_elt_at_index (im->policies, *i);
  82     s = pool_elt_at_index (im->sad, p->sa_index);
  83
  84     if (spi != s->spi)
  85       continue;
  86
  87     if (ipsec_sa_is_set_IS_TUNNEL (s))
  88       {
  89         if (da != clib_net_to_host_u32 (s->tunnel_dst_addr.ip4.as_u32))
  90           continue;
  91
  92         if (sa != clib_net_to_host_u32 (s->tunnel_src_addr.ip4.as_u32))
  93           continue;
  94
  95         return p;
  96       }
  97
  98     if (da < clib_net_to_host_u32 (p->laddr.start.ip4.as_u32))
  99       continue;
 100
 101     if (da > clib_net_to_host_u32 (p->laddr.stop.ip4.as_u32))
 102       continue;
 103
 104     if (sa < clib_net_to_host_u32 (p->raddr.start.ip4.as_u32))
 105       continue;
 106
 107     if (sa > clib_net_to_host_u32 (p->raddr.stop.ip4.as_u32))
 108       continue;
 109
 110     return p;
 111   }
 112   return 0;
 113 }
 114
 115 always_inline uword
 116 ip6_addr_match_range (ip6_address_t * a, ip6_address_t * la,
 117                       ip6_address_t * ua)
 118 {
 119   if ((memcmp (a->as_u64, la->as_u64, 2 * sizeof (u64)) >= 0) &&
 120       (memcmp (a->as_u64, ua->as_u64, 2 * sizeof (u64)) <= 0))
 121     return 1;
 122   return 0;
 123 }
 124
 125 always_inline ipsec_policy_t *
 126 ipsec6_input_protect_policy_match (ipsec_spd_t * spd,
 127                                    ip6_address_t * sa,
 128                                    ip6_address_t * da, u32 spi)
 129 {
 130   ipsec_main_t *im = &ipsec_main;
 131   ipsec_policy_t *p;
 132   ipsec_sa_t *s;
 133   u32 *i;
 134
 135   vec_foreach (i, spd->policies[IPSEC_SPD_POLICY_IP6_INBOUND_PROTECT])
 136   {
 137     p = pool_elt_at_index (im->policies, *i);
 138     s = pool_elt_at_index (im->sad, p->sa_index);
 139
 140     if (spi != s->spi)
 141       continue;
 142
 143     if (ipsec_sa_is_set_IS_TUNNEL (s))
 144       {
 145         if (!ip6_address_is_equal (sa, &s->tunnel_src_addr.ip6))
 146           continue;
 147
 148         if (!ip6_address_is_equal (da, &s->tunnel_dst_addr.ip6))
 149           continue;
 150
 151         return p;
 152       }
 153
 154     if (!ip6_addr_match_range (sa, &p->raddr.start.ip6, &p->raddr.stop.ip6))
 155       continue;
 156
 157     if (!ip6_addr_match_range (da, &p->laddr.start.ip6, &p->laddr.stop.ip6))
 158       continue;
 159
 160     return p;
 161   }
 162   return 0;
 163 }
 164
 165 extern vlib_node_registration_t ipsec4_input_node;
 166
 167 VLIB_NODE_FN (ipsec4_input_node) (vlib_main_t * vm,
 168                                   vlib_node_runtime_t * node,
 169                                   vlib_frame_t * from_frame)
 170 {
 171   u32 n_left_from, *from, next_index, *to_next, thread_index;
 172   ipsec_main_t *im = &ipsec_main;
 173   u32 ipsec_unprocessed = 0;
 174   u32 ipsec_matched = 0;
 175
 176   from = vlib_frame_vector_args (from_frame);
 177   n_left_from = from_frame->n_vectors;
 178   thread_index = vm->thread_index;
 179
 180   next_index = node->cached_next_index;
 181
 182   while (n_left_from > 0)
 183     {
 184       u32 n_left_to_next;
 185
 186       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 187
 188       while (n_left_from > 0 && n_left_to_next > 0)
 189         {
 190           u32 bi0, next0, pi0;
 191           vlib_buffer_t *b0;
 192           ip4_header_t *ip0;
 193           esp_header_t *esp0;
 194           ah_header_t *ah0;
 195           ip4_ipsec_config_t *c0;
 196           ipsec_spd_t *spd0;
 197           ipsec_policy_t *p0 = 0;
 198           u8 has_space0;
 199
 200           bi0 = to_next[0] = from[0];
 201           from += 1;
 202           n_left_from -= 1;
 203           to_next += 1;
 204           n_left_to_next -= 1;
 205
 206           b0 = vlib_get_buffer (vm, bi0);
 207           b0->flags |= VNET_BUFFER_F_IS_IP4;
 208           b0->flags &= ~VNET_BUFFER_F_IS_IP6;
 209           c0 = vnet_feature_next_with_data (&next0, b0, sizeof (c0[0]));
 210
 211           spd0 = pool_elt_at_index (im->spds, c0->spd_index);
 212
 213           ip0 = vlib_buffer_get_current (b0);
 214
 215           if (PREDICT_TRUE
 216               (ip0->protocol == IP_PROTOCOL_IPSEC_ESP
 217                || ip0->protocol == IP_PROTOCOL_UDP))
 218             {
 219 #if 0
 220               clib_warning
 221                 ("packet received from %U to %U spi %u size %u spd_id %u",
 222                  format_ip4_address, ip0->src_address.as_u8,
 223                  format_ip4_address, ip0->dst_address.as_u8,
 224                  clib_net_to_host_u32 (esp0->spi),
 225                  clib_net_to_host_u16 (ip0->length), spd0->id);
 226 #endif
 227
 228               esp0 = (esp_header_t *) ((u8 *) ip0 + ip4_header_bytes (ip0));
 229               if (PREDICT_FALSE (ip0->protocol == IP_PROTOCOL_UDP))
 230                 {
 231                   esp0 =
 232                     (esp_header_t *) ((u8 *) esp0 + sizeof (udp_header_t));
 233                 }
 234
 235               p0 = ipsec_input_protect_policy_match (spd0,
 236                                                      clib_net_to_host_u32
 237                                                      (ip0->src_address.
 238                                                       as_u32),
 239                                                      clib_net_to_host_u32
 240                                                      (ip0->dst_address.
 241                                                       as_u32),
 242                                                      clib_net_to_host_u32
 243                                                      (esp0->spi));
 244
 245               has_space0 =
 246                 vlib_buffer_has_space (b0,
 247                                        (clib_address_t) (esp0 + 1) -
 248                                        (clib_address_t) ip0);
 249
 250               if (PREDICT_TRUE ((p0 != NULL) & (has_space0)))
 251                 {
 252                   ipsec_matched += 1;
 253
 254                   pi0 = p0 - im->policies;
 255                   vlib_increment_combined_counter
 256                     (&ipsec_spd_policy_counters,
 257                      thread_index, pi0, 1,
 258                      clib_net_to_host_u16 (ip0->length));
 259
 260                   vnet_buffer (b0)->ipsec.sad_index = p0->sa_index;
 261                   next0 = im->esp4_decrypt_next_index;
 262                   vlib_buffer_advance (b0, ((u8 *) esp0 - (u8 *) ip0));
 263                   goto trace0;
 264                 }
 265               else
 266                 {
 267                   p0 = 0;
 268                   pi0 = ~0;
 269                 };
 270
 271               /* FIXME bypass and discard */
 272             trace0:
 273               if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE) &&
 274                   PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 275                 {
 276                   ipsec_input_trace_t *tr =
 277                     vlib_add_trace (vm, node, b0, sizeof (*tr));
 278
 279                   tr->proto = ip0->protocol;
 280                   tr->sa_id = p0 ? p0->sa_id : ~0;
 281                   tr->spi =
 282                     has_space0 ? clib_net_to_host_u32 (esp0->spi) : ~0;
 283                   tr->seq =
 284                     has_space0 ? clib_net_to_host_u32 (esp0->seq) : ~0;
 285                   tr->spd = spd0->id;
 286                   tr->policy_index = pi0;
 287                 }
 288             }
 289           else if (ip0->protocol == IP_PROTOCOL_IPSEC_AH)
 290             {
 291               ah0 = (ah_header_t *) ((u8 *) ip0 + ip4_header_bytes (ip0));
 292               p0 = ipsec_input_protect_policy_match (spd0,
 293                                                      clib_net_to_host_u32
 294                                                      (ip0->src_address.
 295                                                       as_u32),
 296                                                      clib_net_to_host_u32
 297                                                      (ip0->dst_address.
 298                                                       as_u32),
 299                                                      clib_net_to_host_u32
 300                                                      (ah0->spi));
 301
 302               has_space0 =
 303                 vlib_buffer_has_space (b0,
 304                                        (clib_address_t) (ah0 + 1) -
 305                                        (clib_address_t) ip0);
 306
 307               if (PREDICT_TRUE ((p0 != NULL) & (has_space0)))
 308                 {
 309                   ipsec_matched += 1;
 310
 311                   pi0 = p0 - im->policies;
 312                   vlib_increment_combined_counter
 313                     (&ipsec_spd_policy_counters,
 314                      thread_index, pi0, 1,
 315                      clib_net_to_host_u16 (ip0->length));
 316
 317                   vnet_buffer (b0)->ipsec.sad_index = p0->sa_index;
 318                   next0 = im->ah4_decrypt_next_index;
 319                   goto trace1;
 320                 }
 321               else
 322                 {
 323                   p0 = 0;
 324                   pi0 = ~0;
 325                 }
 326               /* FIXME bypass and discard */
 327             trace1:
 328               if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE) &&
 329                   PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 330                 {
 331                   ipsec_input_trace_t *tr =
 332                     vlib_add_trace (vm, node, b0, sizeof (*tr));
 333
 334                   tr->proto = ip0->protocol;
 335                   tr->sa_id = p0 ? p0->sa_id : ~0;
 336                   tr->spi = has_space0 ? clib_net_to_host_u32 (ah0->spi) : ~0;
 337                   tr->seq =
 338                     has_space0 ? clib_net_to_host_u32 (ah0->seq_no) : ~0;
 339                   tr->spd = spd0->id;
 340                   tr->policy_index = pi0;
 341                 }
 342             }
 343           else
 344             {
 345               ipsec_unprocessed += 1;
 346             }
 347
 348           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 349                                            to_next, n_left_to_next, bi0,
 350                                            next0);
 351         }
 352       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 353     }
 354
 355   vlib_node_increment_counter (vm, ipsec4_input_node.index,
 356                                IPSEC_INPUT_ERROR_RX_PKTS,
 357                                from_frame->n_vectors - ipsec_unprocessed);
 358
 359   vlib_node_increment_counter (vm, ipsec4_input_node.index,
 360                                IPSEC_INPUT_ERROR_RX_MATCH_PKTS,
 361                                ipsec_matched);
 362   return from_frame->n_vectors;
 363 }
 364
 365
 366 /* *INDENT-OFF* */
 367 VLIB_REGISTER_NODE (ipsec4_input_node) = {
 368   .name = "ipsec4-input-feature",
 369   .vector_size = sizeof (u32),
 370   .format_trace = format_ipsec_input_trace,
 371   .type = VLIB_NODE_TYPE_INTERNAL,
 372   .n_errors = ARRAY_LEN(ipsec_input_error_strings),
 373   .error_strings = ipsec_input_error_strings,
 374   .n_next_nodes = IPSEC_INPUT_N_NEXT,
 375   .next_nodes = {
 376 #define _(s,n) [IPSEC_INPUT_NEXT_##s] = n,
 377     foreach_ipsec_input_next
 378 #undef _
 379   },
 380 };
 381 /* *INDENT-ON* */
 382
 383 extern vlib_node_registration_t ipsec6_input_node;
 384
 385
 386 VLIB_NODE_FN (ipsec6_input_node) (vlib_main_t * vm,
 387                                   vlib_node_runtime_t * node,
 388                                   vlib_frame_t * from_frame)
 389 {
 390   u32 n_left_from, *from, next_index, *to_next, thread_index;
 391   ipsec_main_t *im = &ipsec_main;
 392   u32 ipsec_unprocessed = 0;
 393   u32 ipsec_matched = 0;
 394
 395   from = vlib_frame_vector_args (from_frame);
 396   n_left_from = from_frame->n_vectors;
 397   thread_index = vm->thread_index;
 398
 399   next_index = node->cached_next_index;
 400
 401   while (n_left_from > 0)
 402     {
 403       u32 n_left_to_next;
 404
 405       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 406
 407       while (n_left_from > 0 && n_left_to_next > 0)
 408         {
 409           u32 bi0, next0, pi0;
 410           vlib_buffer_t *b0;
 411           ip6_header_t *ip0;
 412           esp_header_t *esp0;
 413           ip4_ipsec_config_t *c0;
 414           ipsec_spd_t *spd0;
 415           ipsec_policy_t *p0 = 0;
 416           ah_header_t *ah0;
 417           u32 header_size = sizeof (ip0[0]);
 418
 419           bi0 = to_next[0] = from[0];
 420           from += 1;
 421           n_left_from -= 1;
 422           to_next += 1;
 423           n_left_to_next -= 1;
 424
 425           b0 = vlib_get_buffer (vm, bi0);
 426           b0->flags |= VNET_BUFFER_F_IS_IP6;
 427           b0->flags &= ~VNET_BUFFER_F_IS_IP4;
 428           c0 = vnet_feature_next_with_data (&next0, b0, sizeof (c0[0]));
 429
 430           spd0 = pool_elt_at_index (im->spds, c0->spd_index);
 431
 432           ip0 = vlib_buffer_get_current (b0);
 433           esp0 = (esp_header_t *) ((u8 *) ip0 + header_size);
 434           ah0 = (ah_header_t *) ((u8 *) ip0 + header_size);
 435
 436           if (PREDICT_TRUE (ip0->protocol == IP_PROTOCOL_IPSEC_ESP))
 437             {
 438 #if 0
 439               clib_warning
 440                 ("packet received from %U to %U spi %u size %u spd_id %u",
 441                  format_ip6_address, &ip0->src_address, format_ip6_address,
 442                  &ip0->dst_address, clib_net_to_host_u32 (esp0->spi),
 443                  clib_net_to_host_u16 (ip0->payload_length) + header_size,
 444                  spd0->id);
 445 #endif
 446               p0 = ipsec6_input_protect_policy_match (spd0,
 447                                                       &ip0->src_address,
 448                                                       &ip0->dst_address,
 449                                                       clib_net_to_host_u32
 450                                                       (esp0->spi));
 451
 452               if (PREDICT_TRUE (p0 != 0))
 453                 {
 454                   ipsec_matched += 1;
 455
 456                   pi0 = p0 - im->policies;
 457                   vlib_increment_combined_counter
 458                     (&ipsec_spd_policy_counters,
 459                      thread_index, pi0, 1,
 460                      clib_net_to_host_u16 (ip0->payload_length) +
 461                      header_size);
 462
 463                   vnet_buffer (b0)->ipsec.sad_index = p0->sa_index;
 464                   next0 = im->esp6_decrypt_next_index;
 465                   vlib_buffer_advance (b0, header_size);
 466                   goto trace0;
 467                 }
 468               else
 469                 {
 470                   pi0 = ~0;
 471                 }
 472             }
 473           else if (ip0->protocol == IP_PROTOCOL_IPSEC_AH)
 474             {
 475               p0 = ipsec6_input_protect_policy_match (spd0,
 476                                                       &ip0->src_address,
 477                                                       &ip0->dst_address,
 478                                                       clib_net_to_host_u32
 479                                                       (ah0->spi));
 480
 481               if (PREDICT_TRUE (p0 != 0))
 482                 {
 483                   ipsec_matched += 1;
 484                   pi0 = p0 - im->policies;
 485                   vlib_increment_combined_counter
 486                     (&ipsec_spd_policy_counters,
 487                      thread_index, pi0, 1,
 488                      clib_net_to_host_u16 (ip0->payload_length) +
 489                      header_size);
 490
 491                   vnet_buffer (b0)->ipsec.sad_index = p0->sa_index;
 492                   next0 = im->ah6_decrypt_next_index;
 493                   goto trace0;
 494                 }
 495               else
 496                 {
 497                   pi0 = ~0;
 498                 }
 499             }
 500           else
 501             {
 502               ipsec_unprocessed += 1;
 503             }
 504
 505         trace0:
 506           if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE) &&
 507               PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 508             {
 509               ipsec_input_trace_t *tr =
 510                 vlib_add_trace (vm, node, b0, sizeof (*tr));
 511
 512               if (p0)
 513                 tr->sa_id = p0->sa_id;
 514               tr->proto = ip0->protocol;
 515               tr->spi = clib_net_to_host_u32 (esp0->spi);
 516               tr->seq = clib_net_to_host_u32 (esp0->seq);
 517               tr->spd = spd0->id;
 518             }
 519
 520           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 521                                            n_left_to_next, bi0, next0);
 522         }
 523       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 524     }
 525
 526   vlib_node_increment_counter (vm, ipsec6_input_node.index,
 527                                IPSEC_INPUT_ERROR_RX_PKTS,
 528                                from_frame->n_vectors - ipsec_unprocessed);
 529
 530   vlib_node_increment_counter (vm, ipsec6_input_node.index,
 531                                IPSEC_INPUT_ERROR_RX_MATCH_PKTS,
 532                                ipsec_matched);
 533
 534   return from_frame->n_vectors;
 535 }
 536
 537
 538 /* *INDENT-OFF* */
 539 VLIB_REGISTER_NODE (ipsec6_input_node) = {
 540   .name = "ipsec6-input-feature",
 541   .vector_size = sizeof (u32),
 542   .format_trace = format_ipsec_input_trace,
 543   .type = VLIB_NODE_TYPE_INTERNAL,
 544   .n_errors = ARRAY_LEN(ipsec_input_error_strings),
 545   .error_strings = ipsec_input_error_strings,
 546   .n_next_nodes = IPSEC_INPUT_N_NEXT,
 547   .next_nodes = {
 548 #define _(s,n) [IPSEC_INPUT_NEXT_##s] = n,
 549     foreach_ipsec_input_next
 550 #undef _
 551   },
 552 };
 553 /* *INDENT-ON* */
 554
 555 /*
 556  * fd.io coding-style-patch-verification: ON
 557  *
 558  * Local Variables:
 559  * eval: (c-set-style "gnu")
 560  * End:
 561  */