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,
  90                         vlib_buffer_t * b, const esp_header_t * esp)
  91 {
  92   b->error = node->errors[IPSEC_TUN_ERROR_NO_TUNNEL];
  93   b->punt_reason = ipsec_punt_reason[IPSEC_PUNT_IP6_NO_SUCH_TUNNEL];
  94
  95   return VNET_DEVICE_INPUT_NEXT_PUNT;
  96 }
  97
  98 always_inline uword
  99 ipsec_tun_protect_input_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
 100                                 vlib_frame_t * from_frame, int is_ip6)
 101 {
 102   ipsec_main_t *im = &ipsec_main;
 103   vnet_main_t *vnm = im->vnet_main;
 104   vnet_interface_main_t *vim = &vnm->interface_main;
 105
 106   int is_trace = node->flags & VLIB_NODE_FLAG_TRACE;
 107   u32 thread_index = vm->thread_index;
 108
 109   u32 n_left_from, *from;
 110   u16 nexts[VLIB_FRAME_SIZE], *next;
 111   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
 112
 113   from = vlib_frame_vector_args (from_frame);
 114   n_left_from = from_frame->n_vectors;
 115
 116   vlib_get_buffers (vm, from, bufs, n_left_from);
 117   b = bufs;
 118   next = nexts;
 119
 120   clib_memset_u16 (
 121     nexts, is_ip6 ? im->esp6_decrypt_next_index : im->esp4_decrypt_next_index,
 122     n_left_from);
 123
 124   u64 n_bytes = 0, n_packets = 0;
 125   u32 n_disabled = 0, n_no_tunnel = 0;
 126
 127   u32 last_sw_if_index = ~0;
 128   ipsec_tun_lkup_result_t last_result = {
 129     .tun_index = ~0
 130   };
 131   ipsec4_tunnel_kv_t last_key4;
 132   ipsec6_tunnel_kv_t last_key6;
 133   ipsec_tun_lkup_result_t itr0;
 134
 135   vlib_combined_counter_main_t *rx_counter;
 136   vlib_combined_counter_main_t *drop_counter;
 137
 138   if (is_ip6)
 139     clib_memset (&last_key6, 0xff, sizeof (last_key6));
 140   else
 141     last_key4.key = ~0;
 142
 143   rx_counter = vim->combined_sw_if_counters + VNET_INTERFACE_COUNTER_RX;
 144   drop_counter = vim->combined_sw_if_counters + VNET_INTERFACE_COUNTER_DROP;
 145
 146   while (n_left_from > 0)
 147     {
 148       u32 sw_if_index0, len0, hdr_sz0;
 149       clib_bihash_kv_24_16_t bkey60;
 150       clib_bihash_kv_8_16_t bkey40;
 151       ipsec4_tunnel_kv_t *key40;
 152       ipsec6_tunnel_kv_t *key60;
 153       ip4_header_t *ip40;
 154       ip6_header_t *ip60;
 155       esp_header_t *esp0;
 156       u16 buf_rewind0;
 157
 158       ip40 =
 159         (ip4_header_t *) (b[0]->data + vnet_buffer (b[0])->l3_hdr_offset);
 160
 161       key60 = (ipsec6_tunnel_kv_t *) & bkey60;
 162       key40 = (ipsec4_tunnel_kv_t *) & bkey40;
 163
 164       if (is_ip6)
 165         {
 166           ip60 = (ip6_header_t *) ip40;
 167           esp0 = (esp_header_t *) (ip60 + 1);
 168           buf_rewind0 = hdr_sz0 = sizeof (ip6_header_t);
 169         }
 170       else
 171         {
 172           if (ip40->protocol == IP_PROTOCOL_UDP)
 173             {
 174               /* NAT UDP port 4500 case, don't advance any more */
 175               esp0 =
 176                 (esp_header_t *) ((u8 *) ip40 + ip4_header_bytes (ip40) +
 177                                   sizeof (udp_header_t));
 178               hdr_sz0 = 0;
 179               buf_rewind0 = ip4_header_bytes (ip40) + sizeof (udp_header_t);
 180
 181               const udp_header_t *udp0 =
 182                 (udp_header_t *) ((u8 *) ip40 + ip4_header_bytes (ip40));
 183
 184               /* length 9 = sizeof(udp_header) + 1 byte of special SPI */
 185               if (clib_net_to_host_u16 (udp0->length) == 9 &&
 186                   esp0->spi_bytes[0] == 0xff)
 187                 {
 188                   b[0]->error = node->errors[IPSEC_TUN_ERROR_NAT_KEEPALIVE];
 189
 190                   next[0] = VNET_DEVICE_INPUT_NEXT_IP4_DROP;
 191                   len0 = 0;
 192
 193                   vlib_buffer_advance (b[0], -buf_rewind0);
 194                   goto trace00;
 195                 }
 196             }
 197           else
 198             {
 199               esp0 = (esp_header_t *) ((u8 *) ip40 + ip4_header_bytes (ip40));
 200               buf_rewind0 = hdr_sz0 = ip4_header_bytes (ip40);
 201             }
 202         }
 203
 204       /* stats for the tunnel include all the data after the IP header
 205          just like a norml IP-IP tunnel */
 206       vlib_buffer_advance (b[0], hdr_sz0);
 207       len0 = vlib_buffer_length_in_chain (vm, b[0]);
 208
 209       if (len0 < sizeof (esp_header_t))
 210         {
 211           b[0]->error = node->errors[IPSEC_TUN_ERROR_TOO_SHORT];
 212
 213           next[0] = is_ip6 ? VNET_DEVICE_INPUT_NEXT_IP6_DROP :
 214                              VNET_DEVICE_INPUT_NEXT_IP4_DROP;
 215           vlib_buffer_advance (b[0], -buf_rewind0);
 216           goto trace00;
 217         }
 218
 219       if (is_ip6)
 220         {
 221           key60->key.remote_ip = ip60->src_address;
 222           key60->key.spi = esp0->spi;
 223           key60->key.__pad = 0;
 224
 225           if (memcmp (key60, &last_key6, sizeof (last_key6)) == 0)
 226             {
 227               clib_memcpy_fast (&itr0, &last_result, sizeof (itr0));
 228             }
 229           else
 230             {
 231               int rv =
 232                 clib_bihash_search_inline_24_16 (&im->tun6_protect_by_key,
 233                                                  &bkey60);
 234               if (!rv)
 235                 {
 236                   clib_memcpy_fast (&itr0, &bkey60.value, sizeof (itr0));
 237                   clib_memcpy_fast (&last_result, &bkey60.value,
 238                                     sizeof (last_result));
 239                   clib_memcpy_fast (&last_key6, key60, sizeof (last_key6));
 240                 }
 241               else
 242                 {
 243                   next[0] = ipsec_ip6_if_no_tunnel (node, b[0], esp0);
 244                   n_no_tunnel++;
 245                   goto trace00;
 246                 }
 247             }
 248         }
 249       else
 250         {
 251           ipsec4_tunnel_mk_key (key40, &ip40->src_address, esp0->spi);
 252
 253           if (key40->key == last_key4.key)
 254             {
 255               clib_memcpy_fast (&itr0, &last_result, sizeof (itr0));
 256             }
 257           else
 258             {
 259               int rv =
 260                 clib_bihash_search_inline_8_16 (&im->tun4_protect_by_key,
 261                                                 &bkey40);
 262               if (!rv)
 263                 {
 264                   clib_memcpy_fast (&itr0, &bkey40.value, sizeof (itr0));
 265                   clib_memcpy_fast (&last_result, &bkey40.value,
 266                                     sizeof (last_result));
 267                   last_key4.key = key40->key;
 268                 }
 269               else
 270                 {
 271                   next[0] = ipsec_ip4_if_no_tunnel (node, b[0], esp0, ip40);
 272                   vlib_buffer_advance (b[0], -buf_rewind0);
 273                   n_no_tunnel++;
 274                   goto trace00;
 275                 }
 276             }
 277         }
 278
 279       vnet_buffer (b[0])->ipsec.sad_index = itr0.sa_index;
 280       vnet_buffer (b[0])->ipsec.protect_index = itr0.tun_index;
 281
 282       sw_if_index0 = itr0.sw_if_index;
 283       vnet_buffer (b[0])->sw_if_index[VLIB_RX] = sw_if_index0;
 284
 285       if (PREDICT_FALSE (!vnet_sw_interface_is_admin_up (vnm, sw_if_index0)))
 286         {
 287           vlib_increment_combined_counter
 288             (drop_counter, thread_index, sw_if_index0, 1, len0);
 289           n_disabled++;
 290           b[0]->error = node->errors[IPSEC_TUN_ERROR_DISABLED];
 291           next[0] = is_ip6 ? VNET_DEVICE_INPUT_NEXT_IP6_DROP :
 292                              VNET_DEVICE_INPUT_NEXT_IP4_DROP;
 293           goto trace00;
 294         }
 295       else
 296         {
 297           if (PREDICT_TRUE (sw_if_index0 == last_sw_if_index))
 298             {
 299               n_packets++;
 300               n_bytes += len0;
 301             }
 302           else
 303             {
 304               if (n_packets && !(itr0.flags & IPSEC_PROTECT_ENCAPED))
 305                 {
 306                   vlib_increment_combined_counter
 307                     (rx_counter, thread_index, last_sw_if_index,
 308                      n_packets, n_bytes);
 309                 }
 310
 311               last_sw_if_index = sw_if_index0;
 312               n_packets = 1;
 313               n_bytes = len0;
 314             }
 315
 316           //IPSEC_TUN_PROTECT_NEXT_DECRYPT;
 317           next[0] = is_ip6 ? im->esp6_decrypt_tun_next_index :
 318                              im->esp4_decrypt_tun_next_index;
 319
 320           if (itr0.flags & IPSEC_PROTECT_FEAT)
 321             {
 322               u32 next32;
 323               u8 arc = feature_main.device_input_feature_arc_index;
 324
 325               next32 = next[0];
 326               vnet_feature_arc_start (arc, sw_if_index0, &next32, b[0]);
 327               next[0] = next32;
 328             }
 329         }
 330     trace00:
 331       if (PREDICT_FALSE (is_trace))
 332         {
 333           if (b[0]->flags & VLIB_BUFFER_IS_TRACED)
 334             {
 335               ipsec_tun_protect_input_trace_t *tr =
 336                 vlib_add_trace (vm, node, b[0], sizeof (*tr));
 337               if (is_ip6)
 338                 clib_memcpy (&tr->kv6, &bkey60, sizeof (tr->kv6));
 339               else
 340                 clib_memcpy (&tr->kv4, &bkey40, sizeof (tr->kv4));
 341               tr->is_ip6 = is_ip6;
 342               tr->seq = (len0 >= sizeof (*esp0) ?
 343                          clib_host_to_net_u32 (esp0->seq) : ~0);
 344             }
 345         }
 346
 347       /* next */
 348       b += 1;
 349       next += 1;
 350       n_left_from -= 1;
 351     }
 352
 353   if (n_packets && !(itr0.flags & IPSEC_PROTECT_ENCAPED))
 354     vlib_increment_combined_counter (rx_counter,
 355                                      thread_index,
 356                                      last_sw_if_index, n_packets, n_bytes);
 357
 358   vlib_node_increment_counter (vm, node->node_index, IPSEC_TUN_ERROR_RX,
 359                                from_frame->n_vectors -
 360                                  (n_disabled + n_no_tunnel));
 361   vlib_node_increment_counter (vm, node->node_index, IPSEC_TUN_ERROR_NO_TUNNEL,
 362                                n_no_tunnel);
 363
 364   vlib_buffer_enqueue_to_next (vm, node, from, nexts, from_frame->n_vectors);
 365
 366   return from_frame->n_vectors;
 367 }
 368
 369 VLIB_NODE_FN (ipsec4_tun_input_node) (vlib_main_t * vm,
 370                                       vlib_node_runtime_t * node,
 371                                       vlib_frame_t * from_frame)
 372 {
 373   return ipsec_tun_protect_input_inline (vm, node, from_frame, 0);
 374 }
 375
 376 /* *INDENT-OFF* */
 377 VLIB_REGISTER_NODE (ipsec4_tun_input_node) = {
 378   .name = "ipsec4-tun-input",
 379   .vector_size = sizeof (u32),
 380   .format_trace = format_ipsec_tun_protect_input_trace,
 381   .type = VLIB_NODE_TYPE_INTERNAL,
 382   .n_errors = IPSEC_TUN_N_ERROR,
 383   .error_counters = ipsec_tun_error_counters,
 384   .sibling_of = "device-input",
 385 };
 386 /* *INDENT-ON* */
 387
 388 VLIB_NODE_FN (ipsec6_tun_input_node) (vlib_main_t * vm,
 389                                       vlib_node_runtime_t * node,
 390                                       vlib_frame_t * from_frame)
 391 {
 392   return ipsec_tun_protect_input_inline (vm, node, from_frame, 1);
 393 }
 394
 395 /* *INDENT-OFF* */
 396 VLIB_REGISTER_NODE (ipsec6_tun_input_node) = {
 397   .name = "ipsec6-tun-input",
 398   .vector_size = sizeof (u32),
 399   .format_trace = format_ipsec_tun_protect_input_trace,
 400   .type = VLIB_NODE_TYPE_INTERNAL,
 401   .n_errors = IPSEC_TUN_N_ERROR,
 402   .error_counters = ipsec_tun_error_counters,
 403   .sibling_of = "device-input",
 404 };
 405 /* *INDENT-ON* */
 406
 407 /*
 408  * fd.io coding-style-patch-verification: ON
 409  *
 410  * Local Variables:
 411  * eval: (c-set-style "gnu")
 412  * End:
 413  */