src/vnet/ipsec/ipsec_tun_in.c

   1 /*
   2  * ipsec_tun_protect_in.c : IPSec interface input node
   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 #include <vnet/ipsec/ipsec_io.h>
  25 #include <vnet/ipsec/ipsec_punt.h>
  26 #include <vnet/ipsec/ipsec_tun.h>
  27 #include <vnet/ipsec/ipsec.api_enum.h>
  28 #include <vnet/ip/ip4_input.h>
  29
  30 typedef vl_counter_ipsec_tun_enum_t ipsec_tun_protect_input_error_t;
  31
  32 typedef enum ipsec_tun_next_t_
  33 {
  34 #define _(v, s) IPSEC_TUN_PROTECT_NEXT_##v,
  35   foreach_ipsec_input_next
  36 #undef _
  37     IPSEC_TUN_PROTECT_N_NEXT,
  38 } ipsec_tun_next_t;
  39
  40 typedef struct
  41 {
  42   union
  43   {
  44     ipsec4_tunnel_kv_t kv4;
  45     ipsec6_tunnel_kv_t kv6;
  46   };
  47   u8 is_ip6;
  48   u32 seq;
  49 } ipsec_tun_protect_input_trace_t;
  50
  51 static u8 *
  52 format_ipsec_tun_protect_input_trace (u8 * s, va_list * args)
  53 {
  54   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  55   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  56   ipsec_tun_protect_input_trace_t *t =
  57     va_arg (*args, ipsec_tun_protect_input_trace_t *);
  58
  59   if (t->is_ip6)
  60     s = format (s, "IPSec: %U seq %u",
  61                 format_ipsec6_tunnel_kv, &t->kv6, t->seq);
  62   else
  63     s = format (s, "IPSec: %U seq %u sa %d",
  64                 format_ipsec4_tunnel_kv, &t->kv4, t->seq);
  65   return s;
  66 }
  67
  68 always_inline u16
  69 ipsec_ip4_if_no_tunnel (vlib_node_runtime_t * node,
  70                         vlib_buffer_t * b,
  71                         const esp_header_t * esp, const ip4_header_t * ip4)
  72 {
  73   if (PREDICT_FALSE (0 == esp->spi))
  74     {
  75       b->error = node->errors[IPSEC_TUN_ERROR_SPI_0];
  76       b->punt_reason = ipsec_punt_reason[(ip4->protocol == IP_PROTOCOL_UDP ?
  77                                           IPSEC_PUNT_IP4_SPI_UDP_0 :
  78                                           IPSEC_PUNT_IP4_NO_SUCH_TUNNEL)];
  79     }
  80   else
  81     {
  82       b->error = node->errors[IPSEC_TUN_ERROR_NO_TUNNEL];
  83       b->punt_reason = ipsec_punt_reason[IPSEC_PUNT_IP4_NO_SUCH_TUNNEL];
  84     }
  85   return VNET_DEVICE_INPUT_NEXT_PUNT;
  86 }
  87
  88 always_inline u16
  89 ipsec_ip6_if_no_tunnel (vlib_node_runtime_t *node, vlib_buffer_t *b,
  90                         const esp_header_t *esp, const ip6_header_t *ip6)
  91 {
  92   if (PREDICT_FALSE (0 == esp->spi))
  93     {
  94       b->error = node->errors[IPSEC_TUN_ERROR_SPI_0];
  95       b->punt_reason = ipsec_punt_reason[(ip6->protocol == IP_PROTOCOL_UDP ?
  96                                                   IPSEC_PUNT_IP6_SPI_UDP_0 :
  97                                                   IPSEC_PUNT_IP6_NO_SUCH_TUNNEL)];
  98     }
  99   else
 100     {
 101       b->error = node->errors[IPSEC_TUN_ERROR_NO_TUNNEL];
 102       b->punt_reason = ipsec_punt_reason[IPSEC_PUNT_IP6_NO_SUCH_TUNNEL];
 103     }
 104
 105   return VNET_DEVICE_INPUT_NEXT_PUNT;
 106 }
 107
 108 always_inline uword
 109 ipsec_tun_protect_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
 110                                 vlib_frame_t * from_frame, int is_ip6)
 111 {
 112   ipsec_main_t *im = &ipsec_main;
 113   vnet_main_t *vnm = im->vnet_main;
 114   vnet_interface_main_t *vim = &vnm->interface_main;
 115
 116   int is_trace = node->flags & VLIB_NODE_FLAG_TRACE;
 117   u32 thread_index = vm->thread_index;
 118
 119   u32 n_left_from, *from;
 120   u16 nexts[VLIB_FRAME_SIZE], *next;
 121   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
 122
 123   from = vlib_frame_vector_args (from_frame);
 124   n_left_from = from_frame->n_vectors;
 125
 126   vlib_get_buffers (vm, from, bufs, n_left_from);
 127   b = bufs;
 128   next = nexts;
 129
 130   clib_memset_u16 (
 131     nexts, is_ip6 ? im->esp6_decrypt_next_index : im->esp4_decrypt_next_index,
 132     n_left_from);
 133
 134   u64 n_bytes = 0, n_packets = 0;
 135   u32 n_disabled = 0, n_no_tunnel = 0;
 136
 137   u32 last_sw_if_index = ~0;
 138   ipsec_tun_lkup_result_t last_result = {
 139     .tun_index = ~0
 140   };
 141   ipsec4_tunnel_kv_t last_key4;
 142   ipsec6_tunnel_kv_t last_key6;
 143   ipsec_tun_lkup_result_t itr0;
 144
 145   vlib_combined_counter_main_t *rx_counter;
 146   vlib_combined_counter_main_t *drop_counter;
 147
 148   if (is_ip6)
 149     clib_memset (&last_key6, 0xff, sizeof (last_key6));
 150   else
 151     last_key4.key = ~0;
 152
 153   rx_counter = vim->combined_sw_if_counters + VNET_INTERFACE_COUNTER_RX;
 154   drop_counter = vim->combined_sw_if_counters + VNET_INTERFACE_COUNTER_DROP;
 155
 156   while (n_left_from > 0)
 157     {
 158       u32 sw_if_index0, len0, hdr_sz0;
 159       clib_bihash_kv_24_16_t bkey60 = { 0 };
 160       clib_bihash_kv_8_16_t bkey40 = { 0 };
 161       ipsec4_tunnel_kv_t *key40;
 162       ipsec6_tunnel_kv_t *key60;
 163       ip4_header_t *ip40;
 164       ip6_header_t *ip60;
 165       esp_header_t *esp0;
 166       u16 buf_rewind0;
 167
 168       ip40 =
 169         (ip4_header_t *) (b[0]->data + vnet_buffer (b[0])->l3_hdr_offset);
 170
 171       key60 = (ipsec6_tunnel_kv_t *) & bkey60;
 172       key40 = (ipsec4_tunnel_kv_t *) & bkey40;
 173
 174       if (is_ip6)
 175         {
 176           ip60 = (ip6_header_t *) ip40;
 177           if (ip60->protocol == IP_PROTOCOL_UDP)
 178             {
 179               /* NAT UDP port 4500 case, don't advance any more */
 180               esp0 = (esp_header_t *) ((u8 *) ip60 + sizeof (ip6_header_t) +
 181                                        sizeof (udp_header_t));
 182               hdr_sz0 = 0;
 183               buf_rewind0 = sizeof (ip6_header_t) + sizeof (udp_header_t);
 184
 185               const udp_header_t *udp0 =
 186                 (udp_header_t *) ((u8 *) ip60 + sizeof (ip6_header_t));
 187
 188               /* length 9 = sizeof(udp_header) + 1 byte of special SPI */
 189               if (clib_net_to_host_u16 (udp0->length) == 9 &&
 190                   esp0->spi_bytes[0] == 0xff)
 191                 {
 192                   b[0]->error = node->errors[IPSEC_TUN_ERROR_NAT_KEEPALIVE];
 193
 194                   next[0] = VNET_DEVICE_INPUT_NEXT_IP6_DROP;
 195                   len0 = 0;
 196
 197                   vlib_buffer_advance (b[0], -buf_rewind0);
 198                   goto trace00;
 199                 }
 200             }
 201           else
 202             {
 203               esp0 = (esp_header_t *) (ip60 + 1);
 204               buf_rewind0 = hdr_sz0 = sizeof (ip6_header_t);
 205             }
 206         }
 207       else
 208         {
 209           if (ip40->protocol == IP_PROTOCOL_UDP)
 210             {
 211               /* NAT UDP port 4500 case, don't advance any more */
 212               esp0 =
 213                 (esp_header_t *) ((u8 *) ip40 + ip4_header_bytes (ip40) +
 214                                   sizeof (udp_header_t));
 215               hdr_sz0 = 0;
 216               buf_rewind0 = ip4_header_bytes (ip40) + sizeof (udp_header_t);
 217
 218               const udp_header_t *udp0 =
 219                 (udp_header_t *) ((u8 *) ip40 + ip4_header_bytes (ip40));
 220
 221               /* length 9 = sizeof(udp_header) + 1 byte of special SPI */
 222               if (clib_net_to_host_u16 (udp0->length) == 9 &&
 223                   esp0->spi_bytes[0] == 0xff)
 224                 {
 225                   b[0]->error = node->errors[IPSEC_TUN_ERROR_NAT_KEEPALIVE];
 226
 227                   next[0] = VNET_DEVICE_INPUT_NEXT_IP4_DROP;
 228                   len0 = 0;
 229
 230                   vlib_buffer_advance (b[0], -buf_rewind0);
 231                   goto trace00;
 232                 }
 233             }
 234           else
 235             {
 236               esp0 = (esp_header_t *) ((u8 *) ip40 + ip4_header_bytes (ip40));
 237               buf_rewind0 = hdr_sz0 = ip4_header_bytes (ip40);
 238             }
 239         }
 240
 241       /* stats for the tunnel include all the data after the IP header
 242          just like a norml IP-IP tunnel */
 243       vlib_buffer_advance (b[0], hdr_sz0);
 244       len0 = vlib_buffer_length_in_chain (vm, b[0]);
 245
 246       if (len0 < sizeof (esp_header_t))
 247         {
 248           b[0]->error = node->errors[IPSEC_TUN_ERROR_TOO_SHORT];
 249
 250           next[0] = is_ip6 ? VNET_DEVICE_INPUT_NEXT_IP6_DROP :
 251                              VNET_DEVICE_INPUT_NEXT_IP4_DROP;
 252           vlib_buffer_advance (b[0], -buf_rewind0);
 253           goto trace00;
 254         }
 255
 256       if (is_ip6)
 257         {
 258           key60->key.remote_ip = ip60->src_address;
 259           key60->key.spi = esp0->spi;
 260           key60->key.__pad = 0;
 261
 262           if (memcmp (key60, &last_key6, sizeof (last_key6)) == 0)
 263             {
 264               clib_memcpy_fast (&itr0, &last_result, sizeof (itr0));
 265             }
 266           else
 267             {
 268               int rv =
 269                 clib_bihash_search_inline_24_16 (&im->tun6_protect_by_key,
 270                                                  &bkey60);
 271               if (!rv)
 272                 {
 273                   clib_memcpy_fast (&itr0, &bkey60.value, sizeof (itr0));
 274                   clib_memcpy_fast (&last_result, &bkey60.value,
 275                                     sizeof (last_result));
 276                   clib_memcpy_fast (&last_key6, key60, sizeof (last_key6));
 277                 }
 278               else
 279                 {
 280                   next[0] = ipsec_ip6_if_no_tunnel (node, b[0], esp0, ip60);
 281                   n_no_tunnel++;
 282                   goto trace00;
 283                 }
 284             }
 285         }
 286       else
 287         {
 288           ipsec4_tunnel_mk_key (key40, &ip40->src_address, esp0->spi);
 289
 290           if (key40->key == last_key4.key)
 291             {
 292               clib_memcpy_fast (&itr0, &last_result, sizeof (itr0));
 293             }
 294           else
 295             {
 296               int rv =
 297                 clib_bihash_search_inline_8_16 (&im->tun4_protect_by_key,
 298                                                 &bkey40);
 299               if (!rv)
 300                 {
 301                   clib_memcpy_fast (&itr0, &bkey40.value, sizeof (itr0));
 302                   clib_memcpy_fast (&last_result, &bkey40.value,
 303                                     sizeof (last_result));
 304                   last_key4.key = key40->key;
 305                 }
 306               else
 307                 {
 308                   next[0] = ipsec_ip4_if_no_tunnel (node, b[0], esp0, ip40);
 309                   vlib_buffer_advance (b[0], -buf_rewind0);
 310                   n_no_tunnel++;
 311                   goto trace00;
 312                 }
 313             }
 314         }
 315
 316       vnet_buffer (b[0])->ipsec.sad_index = itr0.sa_index;
 317       vnet_buffer (b[0])->ipsec.protect_index = itr0.tun_index;
 318
 319       sw_if_index0 = itr0.sw_if_index;
 320       vnet_buffer (b[0])->sw_if_index[VLIB_RX] = sw_if_index0;
 321
 322       if (PREDICT_FALSE (!vnet_sw_interface_is_admin_up (vnm, sw_if_index0)))
 323         {
 324           vlib_increment_combined_counter
 325             (drop_counter, thread_index, sw_if_index0, 1, len0);
 326           n_disabled++;
 327           b[0]->error = node->errors[IPSEC_TUN_ERROR_DISABLED];
 328           next[0] = is_ip6 ? VNET_DEVICE_INPUT_NEXT_IP6_DROP :
 329                              VNET_DEVICE_INPUT_NEXT_IP4_DROP;
 330           goto trace00;
 331         }
 332       else
 333         {
 334           if (PREDICT_TRUE (sw_if_index0 == last_sw_if_index))
 335             {
 336               n_packets++;
 337               n_bytes += len0;
 338             }
 339           else
 340             {
 341               if (n_packets && !(itr0.flags & IPSEC_PROTECT_ENCAPED))
 342                 {
 343                   vlib_increment_combined_counter
 344                     (rx_counter, thread_index, last_sw_if_index,
 345                      n_packets, n_bytes);
 346                 }
 347
 348               last_sw_if_index = sw_if_index0;
 349               n_packets = 1;
 350               n_bytes = len0;
 351             }
 352
 353           //IPSEC_TUN_PROTECT_NEXT_DECRYPT;
 354           next[0] = is_ip6 ? im->esp6_decrypt_tun_next_index :
 355                              im->esp4_decrypt_tun_next_index;
 356
 357           if (itr0.flags & IPSEC_PROTECT_FEAT)
 358             {
 359               u32 next32;
 360               u8 arc = feature_main.device_input_feature_arc_index;
 361
 362               next32 = next[0];
 363               vnet_feature_arc_start (arc, sw_if_index0, &next32, b[0]);
 364               next[0] = next32;
 365             }
 366         }
 367     trace00:
 368       if (PREDICT_FALSE (is_trace))
 369         {
 370           if (b[0]->flags & VLIB_BUFFER_IS_TRACED)
 371             {
 372               ipsec_tun_protect_input_trace_t *tr =
 373                 vlib_add_trace (vm, node, b[0], sizeof (*tr));
 374               if (is_ip6)
 375                 clib_memcpy (&tr->kv6, &bkey60, sizeof (tr->kv6));
 376               else
 377                 clib_memcpy (&tr->kv4, &bkey40, sizeof (tr->kv4));
 378               tr->is_ip6 = is_ip6;
 379               tr->seq = (len0 >= sizeof (*esp0) ?
 380                          clib_host_to_net_u32 (esp0->seq) : ~0);
 381             }
 382         }
 383
 384       /* next */
 385       b += 1;
 386       next += 1;
 387       n_left_from -= 1;
 388     }
 389
 390   if (n_packets && !(itr0.flags & IPSEC_PROTECT_ENCAPED))
 391     vlib_increment_combined_counter (rx_counter,
 392                                      thread_index,
 393                                      last_sw_if_index, n_packets, n_bytes);
 394
 395   vlib_node_increment_counter (vm, node->node_index, IPSEC_TUN_ERROR_RX,
 396                                from_frame->n_vectors -
 397                                  (n_disabled + n_no_tunnel));
 398   vlib_node_increment_counter (vm, node->node_index, IPSEC_TUN_ERROR_NO_TUNNEL,
 399                                n_no_tunnel);
 400
 401   vlib_buffer_enqueue_to_next (vm, node, from, nexts, from_frame->n_vectors);
 402
 403   return from_frame->n_vectors;
 404 }
 405
 406 VLIB_NODE_FN (ipsec4_tun_input_node) (vlib_main_t * vm,
 407                                       vlib_node_runtime_t * node,
 408                                       vlib_frame_t * from_frame)
 409 {
 410   return ipsec_tun_protect_input_inline (vm, node, from_frame, 0);
 411 }
 412
 413 /* *INDENT-OFF* */
 414 VLIB_REGISTER_NODE (ipsec4_tun_input_node) = {
 415   .name = "ipsec4-tun-input",
 416   .vector_size = sizeof (u32),
 417   .format_trace = format_ipsec_tun_protect_input_trace,
 418   .type = VLIB_NODE_TYPE_INTERNAL,
 419   .n_errors = IPSEC_TUN_N_ERROR,
 420   .error_counters = ipsec_tun_error_counters,
 421   .sibling_of = "device-input",
 422 };
 423 /* *INDENT-ON* */
 424
 425 VLIB_NODE_FN (ipsec6_tun_input_node) (vlib_main_t * vm,
 426                                       vlib_node_runtime_t * node,
 427                                       vlib_frame_t * from_frame)
 428 {
 429   return ipsec_tun_protect_input_inline (vm, node, from_frame, 1);
 430 }
 431
 432 /* *INDENT-OFF* */
 433 VLIB_REGISTER_NODE (ipsec6_tun_input_node) = {
 434   .name = "ipsec6-tun-input",
 435   .vector_size = sizeof (u32),
 436   .format_trace = format_ipsec_tun_protect_input_trace,
 437   .type = VLIB_NODE_TYPE_INTERNAL,
 438   .n_errors = IPSEC_TUN_N_ERROR,
 439   .error_counters = ipsec_tun_error_counters,
 440   .sibling_of = "device-input",
 441 };
 442 /* *INDENT-ON* */
 443
 444 /*
 445  * fd.io coding-style-patch-verification: ON
 446  *
 447  * Local Variables:
 448  * eval: (c-set-style "gnu")
 449  * End:
 450  */