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