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
  22 #include <vnet/ipsec/ipsec.h>
  23 #include <vnet/ipsec/esp.h>
  24
  25 #define foreach_ipsec_input_next                \
  26 _(DROP, "error-drop")                           \
  27 _(ESP_DECRYPT, "esp-decrypt")
  28
  29 #define _(v, s) IPSEC_INPUT_NEXT_##v,
  30 typedef enum
  31 {
  32   foreach_ipsec_input_next
  33 #undef _
  34     IPSEC_INPUT_N_NEXT,
  35 } ipsec_input_next_t;
  36
  37
  38 #define foreach_ipsec_input_error                   \
  39  _(RX_PKTS, "IPSEC pkts received")                  \
  40  _(DECRYPTION_FAILED, "IPSEC decryption failed")
  41
  42
  43 typedef enum
  44 {
  45 #define _(sym,str) IPSEC_INPUT_ERROR_##sym,
  46   foreach_ipsec_input_error
  47 #undef _
  48     IPSEC_INPUT_N_ERROR,
  49 } ipsec_input_error_t;
  50
  51 static char *ipsec_input_error_strings[] = {
  52 #define _(sym,string) string,
  53   foreach_ipsec_input_error
  54 #undef _
  55 };
  56
  57 typedef struct
  58 {
  59   u32 tunnel_index;
  60   u32 spi;
  61   u32 seq;
  62 } ipsec_input_trace_t;
  63
  64 /* packet trace format function */
  65 static u8 *
  66 format_ipsec_input_trace (u8 * s, va_list * args)
  67 {
  68   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  69   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  70   ipsec_input_trace_t *t = va_arg (*args, ipsec_input_trace_t *);
  71
  72   if (t->tunnel_index != ~0)
  73     {
  74       s =
  75         format (s, "esp: tunnel %u spi %u seq %u", t->tunnel_index, t->spi,
  76                 t->seq);
  77     }
  78   else
  79     {
  80       s = format (s, "esp: no tunnel spi %u seq %u", t->spi, t->seq);
  81     }
  82   return s;
  83 }
  84
  85 always_inline ipsec_policy_t *
  86 ipsec_input_protect_policy_match (ipsec_spd_t * spd, u32 sa, u32 da, u32 spi)
  87 {
  88   ipsec_main_t *im = &ipsec_main;
  89   ipsec_policy_t *p;
  90   ipsec_sa_t *s;
  91   u32 *i;
  92
  93   vec_foreach (i, spd->ipv4_inbound_protect_policy_indices)
  94   {
  95     p = pool_elt_at_index (spd->policies, *i);
  96     s = pool_elt_at_index (im->sad, p->sa_index);
  97
  98     if (spi != s->spi)
  99       continue;
 100
 101     if (s->is_tunnel)
 102       {
 103         if (da != clib_net_to_host_u32 (s->tunnel_dst_addr.ip4.as_u32))
 104           continue;
 105
 106         if (sa != clib_net_to_host_u32 (s->tunnel_src_addr.ip4.as_u32))
 107           continue;
 108
 109         return p;
 110       }
 111
 112     if (da < clib_net_to_host_u32 (p->laddr.start.ip4.as_u32))
 113       continue;
 114
 115     if (da > clib_net_to_host_u32 (p->laddr.stop.ip4.as_u32))
 116       continue;
 117
 118     if (sa < clib_net_to_host_u32 (p->raddr.start.ip4.as_u32))
 119       continue;
 120
 121     if (sa > clib_net_to_host_u32 (p->raddr.stop.ip4.as_u32))
 122       continue;
 123
 124     return p;
 125   }
 126   return 0;
 127 }
 128
 129 always_inline uword
 130 ip6_addr_match_range (ip6_address_t * a, ip6_address_t * la,
 131                       ip6_address_t * ua)
 132 {
 133   if ((memcmp (a->as_u64, la->as_u64, 2 * sizeof (u64)) >= 0) &&
 134       (memcmp (a->as_u64, ua->as_u64, 2 * sizeof (u64)) <= 0))
 135     return 1;
 136   return 0;
 137 }
 138
 139 always_inline ipsec_policy_t *
 140 ipsec_input_ip6_protect_policy_match (ipsec_spd_t * spd,
 141                                       ip6_address_t * sa,
 142                                       ip6_address_t * da, u32 spi)
 143 {
 144   ipsec_main_t *im = &ipsec_main;
 145   ipsec_policy_t *p;
 146   ipsec_sa_t *s;
 147   u32 *i;
 148
 149   vec_foreach (i, spd->ipv6_inbound_protect_policy_indices)
 150   {
 151     p = pool_elt_at_index (spd->policies, *i);
 152     s = pool_elt_at_index (im->sad, p->sa_index);
 153
 154     if (spi != s->spi)
 155       continue;
 156
 157     if (s->is_tunnel)
 158       {
 159         if (!ip6_address_is_equal (sa, &s->tunnel_src_addr.ip6))
 160           continue;
 161
 162         if (!ip6_address_is_equal (da, &s->tunnel_dst_addr.ip6))
 163           continue;
 164
 165         return p;
 166       }
 167
 168     if (!ip6_addr_match_range (sa, &p->raddr.start.ip6, &p->raddr.stop.ip6))
 169       continue;
 170
 171     if (!ip6_addr_match_range (da, &p->laddr.start.ip6, &p->laddr.stop.ip6))
 172       continue;
 173
 174     return p;
 175   }
 176   return 0;
 177 }
 178
 179 static vlib_node_registration_t ipsec_input_ip4_node;
 180
 181 static uword
 182 ipsec_input_ip4_node_fn (vlib_main_t * vm,
 183                          vlib_node_runtime_t * node,
 184                          vlib_frame_t * from_frame)
 185 {
 186   ip4_main_t *i4m = &ip4_main;
 187   ip_lookup_main_t *lm = &i4m->lookup_main;
 188   ip_config_main_t *cm = &lm->rx_config_mains[VNET_UNICAST];
 189   u32 n_left_from, *from, next_index, *to_next;
 190   ipsec_main_t *im = &ipsec_main;
 191
 192   from = vlib_frame_vector_args (from_frame);
 193   n_left_from = from_frame->n_vectors;
 194
 195   next_index = node->cached_next_index;
 196
 197   while (n_left_from > 0)
 198     {
 199       u32 n_left_to_next;
 200
 201       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 202
 203       while (n_left_from > 0 && n_left_to_next > 0)
 204         {
 205           u32 bi0, next0;
 206           vlib_buffer_t *b0;
 207           ip4_header_t *ip0;
 208           esp_header_t *esp0;
 209           ip4_ipsec_config_t *c0;
 210           u32 tunnel_index0 = ~0;
 211           ipsec_spd_t *spd0;
 212
 213           bi0 = to_next[0] = from[0];
 214           from += 1;
 215           n_left_from -= 1;
 216           to_next += 1;
 217           n_left_to_next -= 1;
 218
 219           b0 = vlib_get_buffer (vm, bi0);
 220           c0 = vnet_get_config_data (&cm->config_main,
 221                                      &b0->current_config_index,
 222                                      &next0, sizeof (c0[0]));
 223
 224           spd0 = pool_elt_at_index (im->spds, c0->spd_index);
 225
 226           ip0 = vlib_buffer_get_current (b0);
 227           esp0 = (esp_header_t *) ((u8 *) ip0 + ip4_header_bytes (ip0));
 228
 229           if (PREDICT_TRUE (ip0->protocol == IP_PROTOCOL_IPSEC_ESP))
 230             {
 231 #if 0
 232               clib_warning
 233                 ("packet received from %U to %U spi %u size %u spd_id %u",
 234                  format_ip4_address, ip0->src_address.as_u8,
 235                  format_ip4_address, ip0->dst_address.as_u8,
 236                  clib_net_to_host_u32 (esp0->spi),
 237                  clib_net_to_host_u16 (ip0->length), spd0->id);
 238 #endif
 239               ipsec_policy_t *p0;
 240               p0 = ipsec_input_protect_policy_match (spd0,
 241                                                      clib_net_to_host_u32
 242                                                      (ip0->src_address.
 243                                                       as_u32),
 244                                                      clib_net_to_host_u32
 245                                                      (ip0->dst_address.
 246                                                       as_u32),
 247                                                      clib_net_to_host_u32
 248                                                      (esp0->spi));
 249
 250               if (PREDICT_TRUE (p0 != 0))
 251                 {
 252                   p0->counter.packets++;
 253                   p0->counter.bytes += clib_net_to_host_u16 (ip0->length);
 254                   vnet_buffer (b0)->output_features.ipsec_sad_index =
 255                     p0->sa_index;
 256                   next0 = IPSEC_INPUT_NEXT_ESP_DECRYPT;
 257                   vlib_buffer_advance (b0, ip4_header_bytes (ip0));
 258                   goto trace0;
 259                 }
 260             }
 261
 262           /* FIXME bypass and discard */
 263
 264         trace0:
 265           if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 266             {
 267               ipsec_input_trace_t *tr =
 268                 vlib_add_trace (vm, node, b0, sizeof (*tr));
 269               tr->tunnel_index = tunnel_index0;
 270               tr->spi = clib_host_to_net_u32 (esp0->spi);
 271               tr->seq = clib_host_to_net_u32 (esp0->seq);
 272             }
 273
 274           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 275                                            to_next, n_left_to_next, bi0,
 276                                            next0);
 277         }
 278       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 279     }
 280   vlib_node_increment_counter (vm, ipsec_input_ip4_node.index,
 281                                IPSEC_INPUT_ERROR_RX_PKTS,
 282                                from_frame->n_vectors);
 283
 284   return from_frame->n_vectors;
 285 }
 286
 287
 288 /* *INDENT-OFF* */
 289 VLIB_REGISTER_NODE (ipsec_input_ip4_node,static) = {
 290   .function = ipsec_input_ip4_node_fn,
 291   .name = "ipsec-input-ip4",
 292   .vector_size = sizeof (u32),
 293   .format_trace = format_ipsec_input_trace,
 294   .type = VLIB_NODE_TYPE_INTERNAL,
 295
 296   .n_errors = ARRAY_LEN(ipsec_input_error_strings),
 297   .error_strings = ipsec_input_error_strings,
 298
 299   .n_next_nodes = IPSEC_INPUT_N_NEXT,
 300   .next_nodes = {
 301 #define _(s,n) [IPSEC_INPUT_NEXT_##s] = n,
 302     foreach_ipsec_input_next
 303 #undef _
 304   },
 305 };
 306 /* *INDENT-ON* */
 307
 308 VLIB_NODE_FUNCTION_MULTIARCH (ipsec_input_ip4_node, ipsec_input_ip4_node_fn)
 309      static vlib_node_registration_t ipsec_input_ip6_node;
 310
 311      static uword
 312        ipsec_input_ip6_node_fn (vlib_main_t * vm,
 313                                 vlib_node_runtime_t * node,
 314                                 vlib_frame_t * from_frame)
 315 {
 316   ip6_main_t *i6m = &ip6_main;
 317   ip_lookup_main_t *lm = &i6m->lookup_main;
 318   ip_config_main_t *cm = &lm->rx_config_mains[VNET_UNICAST];
 319   u32 n_left_from, *from, next_index, *to_next;
 320   ipsec_main_t *im = &ipsec_main;
 321
 322   from = vlib_frame_vector_args (from_frame);
 323   n_left_from = from_frame->n_vectors;
 324
 325   next_index = node->cached_next_index;
 326
 327   while (n_left_from > 0)
 328     {
 329       u32 n_left_to_next;
 330
 331       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 332
 333       while (n_left_from > 0 && n_left_to_next > 0)
 334         {
 335           u32 bi0, next0;
 336           vlib_buffer_t *b0;
 337           ip6_header_t *ip0;
 338           esp_header_t *esp0;
 339           ip4_ipsec_config_t *c0;
 340           u32 tunnel_index0 = ~0;
 341           ipsec_spd_t *spd0;
 342           u32 header_size = sizeof (ip0[0]);
 343
 344           bi0 = to_next[0] = from[0];
 345           from += 1;
 346           n_left_from -= 1;
 347           to_next += 1;
 348           n_left_to_next -= 1;
 349
 350           b0 = vlib_get_buffer (vm, bi0);
 351           c0 = vnet_get_config_data (&cm->config_main,
 352                                      &b0->current_config_index,
 353                                      &next0, sizeof (c0[0]));
 354
 355           spd0 = pool_elt_at_index (im->spds, c0->spd_index);
 356
 357           ip0 = vlib_buffer_get_current (b0);
 358           esp0 = (esp_header_t *) ((u8 *) ip0 + header_size);
 359
 360           if (PREDICT_TRUE (ip0->protocol == IP_PROTOCOL_IPSEC_ESP))
 361             {
 362 #if 0
 363               clib_warning
 364                 ("packet received from %U to %U spi %u size %u spd_id %u",
 365                  format_ip6_address, &ip0->src_address, format_ip6_address,
 366                  &ip0->dst_address, clib_net_to_host_u32 (esp0->spi),
 367                  clib_net_to_host_u16 (ip0->payload_length) + header_size,
 368                  spd0->id);
 369 #endif
 370               ipsec_policy_t *p0;
 371               p0 = ipsec_input_ip6_protect_policy_match (spd0,
 372                                                          &ip0->src_address,
 373                                                          &ip0->dst_address,
 374                                                          clib_net_to_host_u32
 375                                                          (esp0->spi));
 376
 377               if (PREDICT_TRUE (p0 != 0))
 378                 {
 379                   p0->counter.packets++;
 380                   p0->counter.bytes +=
 381                     clib_net_to_host_u16 (ip0->payload_length);
 382                   p0->counter.bytes += header_size;
 383                   vnet_buffer (b0)->output_features.ipsec_sad_index =
 384                     p0->sa_index;
 385                   next0 = IPSEC_INPUT_NEXT_ESP_DECRYPT;
 386                   vlib_buffer_advance (b0, header_size);
 387                   goto trace0;
 388                 }
 389             }
 390
 391         trace0:
 392           if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 393             {
 394               ipsec_input_trace_t *tr =
 395                 vlib_add_trace (vm, node, b0, sizeof (*tr));
 396               tr->tunnel_index = tunnel_index0;
 397               tr->spi = clib_host_to_net_u32 (esp0->spi);
 398               tr->seq = clib_host_to_net_u32 (esp0->seq);
 399             }
 400
 401           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 402                                            n_left_to_next, bi0, next0);
 403         }
 404       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 405     }
 406   vlib_node_increment_counter (vm, ipsec_input_ip6_node.index,
 407                                IPSEC_INPUT_ERROR_RX_PKTS,
 408                                from_frame->n_vectors);
 409
 410   return from_frame->n_vectors;
 411 }
 412
 413
 414 /* *INDENT-OFF* */
 415 VLIB_REGISTER_NODE (ipsec_input_ip6_node,static) = {
 416   .function = ipsec_input_ip6_node_fn,
 417   .name = "ipsec-input-ip6",
 418   .vector_size = sizeof (u32),
 419   .format_trace = format_ipsec_input_trace,
 420   .type = VLIB_NODE_TYPE_INTERNAL,
 421
 422   .n_errors = ARRAY_LEN(ipsec_input_error_strings),
 423   .error_strings = ipsec_input_error_strings,
 424
 425   .n_next_nodes = IPSEC_INPUT_N_NEXT,
 426   .next_nodes = {
 427 #define _(s,n) [IPSEC_INPUT_NEXT_##s] = n,
 428     foreach_ipsec_input_next
 429 #undef _
 430   },
 431 };
 432 /* *INDENT-ON* */
 433
 434 VLIB_NODE_FUNCTION_MULTIARCH (ipsec_input_ip6_node, ipsec_input_ip6_node_fn)
 435 /*
 436  * fd.io coding-style-patch-verification: ON
 437  *
 438  * Local Variables:
 439  * eval: (c-set-style "gnu")
 440  * End:
 441  */