vnet/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
  26 #define foreach_ipsec_input_next                \
  27 _(DROP, "error-drop")                           \
  28 _(ESP_DECRYPT, "esp-decrypt")
  29
  30 #define _(v, s) IPSEC_INPUT_NEXT_##v,
  31 typedef enum
  32 {
  33   foreach_ipsec_input_next
  34 #undef _
  35     IPSEC_INPUT_N_NEXT,
  36 } ipsec_input_next_t;
  37
  38
  39 #define foreach_ipsec_input_error                   \
  40  _(RX_PKTS, "IPSEC pkts received")                  \
  41  _(DECRYPTION_FAILED, "IPSEC decryption failed")
  42
  43
  44 typedef enum
  45 {
  46 #define _(sym,str) IPSEC_INPUT_ERROR_##sym,
  47   foreach_ipsec_input_error
  48 #undef _
  49     IPSEC_INPUT_N_ERROR,
  50 } ipsec_input_error_t;
  51
  52 static char *ipsec_input_error_strings[] = {
  53 #define _(sym,string) string,
  54   foreach_ipsec_input_error
  55 #undef _
  56 };
  57
  58 typedef struct
  59 {
  60   u32 sa_id;
  61   u32 spi;
  62   u32 seq;
  63 } ipsec_input_trace_t;
  64
  65 /* packet trace format function */
  66 static u8 *
  67 format_ipsec_input_trace (u8 * s, va_list * args)
  68 {
  69   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  70   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  71   ipsec_input_trace_t *t = va_arg (*args, ipsec_input_trace_t *);
  72
  73   if (t->spi == 0 && t->seq == 0)
  74     {
  75       s = format (s, "esp: no esp packet");
  76       return s;
  77     }
  78
  79   if (t->sa_id != 0)
  80     {
  81       s = format (s, "esp: sa_id %u spi %u seq %u", t->sa_id, t->spi, t->seq);
  82     }
  83   else
  84     {
  85       s = format (s, "esp: no sa spi %u seq %u", t->spi, t->seq);
  86     }
  87   return s;
  88 }
  89
  90 always_inline ipsec_policy_t *
  91 ipsec_input_protect_policy_match (ipsec_spd_t * spd, u32 sa, u32 da, u32 spi)
  92 {
  93   ipsec_main_t *im = &ipsec_main;
  94   ipsec_policy_t *p;
  95   ipsec_sa_t *s;
  96   u32 *i;
  97
  98   vec_foreach (i, spd->ipv4_inbound_protect_policy_indices)
  99   {
 100     p = pool_elt_at_index (spd->policies, *i);
 101     s = pool_elt_at_index (im->sad, p->sa_index);
 102
 103     if (spi != s->spi)
 104       continue;
 105
 106     if (s->is_tunnel)
 107       {
 108         if (da != clib_net_to_host_u32 (s->tunnel_dst_addr.ip4.as_u32))
 109           continue;
 110
 111         if (sa != clib_net_to_host_u32 (s->tunnel_src_addr.ip4.as_u32))
 112           continue;
 113
 114         return p;
 115       }
 116
 117     if (da < clib_net_to_host_u32 (p->laddr.start.ip4.as_u32))
 118       continue;
 119
 120     if (da > clib_net_to_host_u32 (p->laddr.stop.ip4.as_u32))
 121       continue;
 122
 123     if (sa < clib_net_to_host_u32 (p->raddr.start.ip4.as_u32))
 124       continue;
 125
 126     if (sa > clib_net_to_host_u32 (p->raddr.stop.ip4.as_u32))
 127       continue;
 128
 129     return p;
 130   }
 131   return 0;
 132 }
 133
 134 always_inline uword
 135 ip6_addr_match_range (ip6_address_t * a, ip6_address_t * la,
 136                       ip6_address_t * ua)
 137 {
 138   if ((memcmp (a->as_u64, la->as_u64, 2 * sizeof (u64)) >= 0) &&
 139       (memcmp (a->as_u64, ua->as_u64, 2 * sizeof (u64)) <= 0))
 140     return 1;
 141   return 0;
 142 }
 143
 144 always_inline ipsec_policy_t *
 145 ipsec_input_ip6_protect_policy_match (ipsec_spd_t * spd,
 146                                       ip6_address_t * sa,
 147                                       ip6_address_t * da, u32 spi)
 148 {
 149   ipsec_main_t *im = &ipsec_main;
 150   ipsec_policy_t *p;
 151   ipsec_sa_t *s;
 152   u32 *i;
 153
 154   vec_foreach (i, spd->ipv6_inbound_protect_policy_indices)
 155   {
 156     p = pool_elt_at_index (spd->policies, *i);
 157     s = pool_elt_at_index (im->sad, p->sa_index);
 158
 159     if (spi != s->spi)
 160       continue;
 161
 162     if (s->is_tunnel)
 163       {
 164         if (!ip6_address_is_equal (sa, &s->tunnel_src_addr.ip6))
 165           continue;
 166
 167         if (!ip6_address_is_equal (da, &s->tunnel_dst_addr.ip6))
 168           continue;
 169
 170         return p;
 171       }
 172
 173     if (!ip6_addr_match_range (sa, &p->raddr.start.ip6, &p->raddr.stop.ip6))
 174       continue;
 175
 176     if (!ip6_addr_match_range (da, &p->laddr.start.ip6, &p->laddr.stop.ip6))
 177       continue;
 178
 179     return p;
 180   }
 181   return 0;
 182 }
 183
 184 static vlib_node_registration_t ipsec_input_ip4_node;
 185
 186 static uword
 187 ipsec_input_ip4_node_fn (vlib_main_t * vm,
 188                          vlib_node_runtime_t * node,
 189                          vlib_frame_t * from_frame)
 190 {
 191   u32 n_left_from, *from, next_index, *to_next;
 192   ipsec_main_t *im = &ipsec_main;
 193
 194   from = vlib_frame_vector_args (from_frame);
 195   n_left_from = from_frame->n_vectors;
 196
 197   next_index = node->cached_next_index;
 198
 199   while (n_left_from > 0)
 200     {
 201       u32 n_left_to_next;
 202
 203       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 204
 205       while (n_left_from > 0 && n_left_to_next > 0)
 206         {
 207           u32 bi0, next0;
 208           vlib_buffer_t *b0;
 209           ip4_header_t *ip0;
 210           esp_header_t *esp0;
 211           ip4_ipsec_config_t *c0;
 212           ipsec_spd_t *spd0;
 213           ipsec_policy_t *p0 = 0;
 214
 215           bi0 = to_next[0] = from[0];
 216           from += 1;
 217           n_left_from -= 1;
 218           to_next += 1;
 219           n_left_to_next -= 1;
 220
 221           b0 = vlib_get_buffer (vm, bi0);
 222           c0 =
 223             vnet_feature_next_with_data (vnet_buffer (b0)->sw_if_index
 224                                          [VLIB_RX], &next0, b0,
 225                                          sizeof (c0[0]));
 226
 227           spd0 = pool_elt_at_index (im->spds, c0->spd_index);
 228
 229           ip0 = vlib_buffer_get_current (b0);
 230           esp0 = (esp_header_t *) ((u8 *) ip0 + ip4_header_bytes (ip0));
 231
 232           if (PREDICT_TRUE (ip0->protocol == IP_PROTOCOL_IPSEC_ESP))
 233             {
 234 #if 0
 235               clib_warning
 236                 ("packet received from %U to %U spi %u size %u spd_id %u",
 237                  format_ip4_address, ip0->src_address.as_u8,
 238                  format_ip4_address, ip0->dst_address.as_u8,
 239                  clib_net_to_host_u32 (esp0->spi),
 240                  clib_net_to_host_u16 (ip0->length), spd0->id);
 241 #endif
 242
 243               p0 = ipsec_input_protect_policy_match (spd0,
 244                                                      clib_net_to_host_u32
 245                                                      (ip0->src_address.
 246                                                       as_u32),
 247                                                      clib_net_to_host_u32
 248                                                      (ip0->dst_address.
 249                                                       as_u32),
 250                                                      clib_net_to_host_u32
 251                                                      (esp0->spi));
 252
 253               if (PREDICT_TRUE (p0 != 0))
 254                 {
 255                   p0->counter.packets++;
 256                   p0->counter.bytes += clib_net_to_host_u16 (ip0->length);
 257                   vnet_buffer (b0)->ipsec.sad_index = p0->sa_index;
 258                   vnet_buffer (b0)->ipsec.flags = 0;
 259                   next0 = IPSEC_INPUT_NEXT_ESP_DECRYPT;
 260                   vlib_buffer_advance (b0, ip4_header_bytes (ip0));
 261                   goto trace0;
 262                 }
 263             }
 264
 265           /* FIXME bypass and discard */
 266
 267         trace0:
 268           if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 269             {
 270               ipsec_input_trace_t *tr =
 271                 vlib_add_trace (vm, node, b0, sizeof (*tr));
 272               if (ip0->protocol == IP_PROTOCOL_IPSEC_ESP)
 273                 {
 274                   if (p0)
 275                     tr->sa_id = p0->sa_id;
 276                   tr->spi = clib_host_to_net_u32 (esp0->spi);
 277                   tr->seq = clib_host_to_net_u32 (esp0->seq);
 278                 }
 279             }
 280
 281           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 282                                            to_next, n_left_to_next, bi0,
 283                                            next0);
 284         }
 285       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 286     }
 287   vlib_node_increment_counter (vm, ipsec_input_ip4_node.index,
 288                                IPSEC_INPUT_ERROR_RX_PKTS,
 289                                from_frame->n_vectors);
 290
 291   return from_frame->n_vectors;
 292 }
 293
 294
 295 /* *INDENT-OFF* */
 296 VLIB_REGISTER_NODE (ipsec_input_ip4_node,static) = {
 297   .function = ipsec_input_ip4_node_fn,
 298   .name = "ipsec-input-ip4",
 299   .vector_size = sizeof (u32),
 300   .format_trace = format_ipsec_input_trace,
 301   .type = VLIB_NODE_TYPE_INTERNAL,
 302
 303   .n_errors = ARRAY_LEN(ipsec_input_error_strings),
 304   .error_strings = ipsec_input_error_strings,
 305
 306   .n_next_nodes = IPSEC_INPUT_N_NEXT,
 307   .next_nodes = {
 308 #define _(s,n) [IPSEC_INPUT_NEXT_##s] = n,
 309     foreach_ipsec_input_next
 310 #undef _
 311   },
 312 };
 313 /* *INDENT-ON* */
 314
 315 VLIB_NODE_FUNCTION_MULTIARCH (ipsec_input_ip4_node, ipsec_input_ip4_node_fn)
 316      static vlib_node_registration_t ipsec_input_ip6_node;
 317
 318      static uword
 319        ipsec_input_ip6_node_fn (vlib_main_t * vm,
 320                                 vlib_node_runtime_t * node,
 321                                 vlib_frame_t * from_frame)
 322 {
 323   u32 n_left_from, *from, next_index, *to_next;
 324   ipsec_main_t *im = &ipsec_main;
 325
 326   from = vlib_frame_vector_args (from_frame);
 327   n_left_from = from_frame->n_vectors;
 328
 329   next_index = node->cached_next_index;
 330
 331   while (n_left_from > 0)
 332     {
 333       u32 n_left_to_next;
 334
 335       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 336
 337       while (n_left_from > 0 && n_left_to_next > 0)
 338         {
 339           u32 bi0, next0;
 340           vlib_buffer_t *b0;
 341           ip6_header_t *ip0;
 342           esp_header_t *esp0;
 343           ip4_ipsec_config_t *c0;
 344           ipsec_spd_t *spd0;
 345           ipsec_policy_t *p0 = 0;
 346           u32 header_size = sizeof (ip0[0]);
 347
 348           bi0 = to_next[0] = from[0];
 349           from += 1;
 350           n_left_from -= 1;
 351           to_next += 1;
 352           n_left_to_next -= 1;
 353
 354           b0 = vlib_get_buffer (vm, bi0);
 355           c0 =
 356             vnet_feature_next_with_data (vnet_buffer (b0)->sw_if_index
 357                                          [VLIB_RX], &next0, b0,
 358                                          sizeof (c0[0]));
 359
 360           spd0 = pool_elt_at_index (im->spds, c0->spd_index);
 361
 362           ip0 = vlib_buffer_get_current (b0);
 363           esp0 = (esp_header_t *) ((u8 *) ip0 + header_size);
 364
 365           if (PREDICT_TRUE (ip0->protocol == IP_PROTOCOL_IPSEC_ESP))
 366             {
 367 #if 0
 368               clib_warning
 369                 ("packet received from %U to %U spi %u size %u spd_id %u",
 370                  format_ip6_address, &ip0->src_address, format_ip6_address,
 371                  &ip0->dst_address, clib_net_to_host_u32 (esp0->spi),
 372                  clib_net_to_host_u16 (ip0->payload_length) + header_size,
 373                  spd0->id);
 374 #endif
 375               p0 = ipsec_input_ip6_protect_policy_match (spd0,
 376                                                          &ip0->src_address,
 377                                                          &ip0->dst_address,
 378                                                          clib_net_to_host_u32
 379                                                          (esp0->spi));
 380
 381               if (PREDICT_TRUE (p0 != 0))
 382                 {
 383                   p0->counter.packets++;
 384                   p0->counter.bytes +=
 385                     clib_net_to_host_u16 (ip0->payload_length);
 386                   p0->counter.bytes += header_size;
 387                   vnet_buffer (b0)->ipsec.sad_index = p0->sa_index;
 388                   vnet_buffer (b0)->ipsec.flags = 0;
 389                   next0 = IPSEC_INPUT_NEXT_ESP_DECRYPT;
 390                   vlib_buffer_advance (b0, header_size);
 391                   goto trace0;
 392                 }
 393             }
 394
 395         trace0:
 396           if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 397             {
 398               ipsec_input_trace_t *tr =
 399                 vlib_add_trace (vm, node, b0, sizeof (*tr));
 400               if (ip0->protocol == IP_PROTOCOL_IPSEC_ESP)
 401                 {
 402                   if (p0)
 403                     tr->sa_id = p0->sa_id;
 404                   tr->spi = clib_host_to_net_u32 (esp0->spi);
 405                   tr->seq = clib_host_to_net_u32 (esp0->seq);
 406                 }
 407             }
 408
 409           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 410                                            n_left_to_next, bi0, next0);
 411         }
 412       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 413     }
 414   vlib_node_increment_counter (vm, ipsec_input_ip6_node.index,
 415                                IPSEC_INPUT_ERROR_RX_PKTS,
 416                                from_frame->n_vectors);
 417
 418   return from_frame->n_vectors;
 419 }
 420
 421
 422 /* *INDENT-OFF* */
 423 VLIB_REGISTER_NODE (ipsec_input_ip6_node,static) = {
 424   .function = ipsec_input_ip6_node_fn,
 425   .name = "ipsec-input-ip6",
 426   .vector_size = sizeof (u32),
 427   .format_trace = format_ipsec_input_trace,
 428   .type = VLIB_NODE_TYPE_INTERNAL,
 429
 430   .n_errors = ARRAY_LEN(ipsec_input_error_strings),
 431   .error_strings = ipsec_input_error_strings,
 432
 433   .n_next_nodes = IPSEC_INPUT_N_NEXT,
 434   .next_nodes = {
 435 #define _(s,n) [IPSEC_INPUT_NEXT_##s] = n,
 436     foreach_ipsec_input_next
 437 #undef _
 438   },
 439 };
 440 /* *INDENT-ON* */
 441
 442 VLIB_NODE_FUNCTION_MULTIARCH (ipsec_input_ip6_node, ipsec_input_ip6_node_fn)
 443 /*
 444  * fd.io coding-style-patch-verification: ON
 445  *
 446  * Local Variables:
 447  * eval: (c-set-style "gnu")
 448  * End:
 449  */