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 vlib_node_registration_t ipsec_input_node;
  56
  57 typedef struct {
  58   u32 tunnel_index;
  59   u32 spi;
  60   u32 seq;
  61 } ipsec_input_trace_t;
  62
  63 /* packet trace format function */
  64 static u8 * format_ipsec_input_trace (u8 * s, va_list * args)
  65 {
  66   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  67   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  68   ipsec_input_trace_t * t = va_arg (*args, ipsec_input_trace_t *);
  69
  70   if (t->tunnel_index != ~0)
  71   {
  72     s = format (s, "esp: tunnel %u spi %u seq %u", t->tunnel_index, t->spi, t->seq);
  73   }
  74   else
  75   {
  76     s = format (s, "esp: no tunnel spi %u seq %u",t->spi, t->seq);
  77   }
  78   return s;
  79 }
  80
  81 always_inline ipsec_policy_t *
  82 ipsec_input_protect_policy_match(ipsec_spd_t * spd, u32 sa, u32 da, u32 spi)
  83 {
  84   ipsec_main_t *im = &ipsec_main;
  85   ipsec_policy_t * p;
  86   ipsec_sa_t * s;
  87   u32 * i;
  88
  89   vec_foreach(i, spd->ipv4_inbound_protect_policy_indices)
  90     {
  91       p = pool_elt_at_index(spd->policies, *i);
  92       s = pool_elt_at_index(im->sad, p->sa_index);
  93
  94       if (spi != s->spi)
  95         continue;
  96
  97       if (s->is_tunnel)
  98         {
  99            if (da != clib_net_to_host_u32(s->tunnel_dst_addr.ip4.as_u32))
 100                continue;
 101
 102            if (sa != clib_net_to_host_u32(s->tunnel_src_addr.ip4.as_u32))
 103                continue;
 104
 105            return p;
 106         }
 107
 108       if (da < clib_net_to_host_u32(p->laddr.start.ip4.as_u32))
 109         continue;
 110
 111       if (da > clib_net_to_host_u32(p->laddr.stop.ip4.as_u32))
 112         continue;
 113
 114       if (sa < clib_net_to_host_u32(p->raddr.start.ip4.as_u32))
 115         continue;
 116
 117       if (sa > clib_net_to_host_u32(p->raddr.stop.ip4.as_u32))
 118         continue;
 119
 120       return p;
 121     }
 122     return 0;
 123 }
 124
 125 always_inline uword
 126 ip6_addr_match_range (ip6_address_t * a, ip6_address_t * la, ip6_address_t * ua)
 127 {
 128   if ((memcmp(a->as_u64, la->as_u64, 2 * sizeof(u64)) >= 0) &&
 129       (memcmp(a->as_u64, ua->as_u64, 2 * sizeof(u64)) <= 0))
 130     return 1;
 131   return 0;
 132 }
 133
 134 always_inline ipsec_policy_t *
 135 ipsec_input_ip6_protect_policy_match (ipsec_spd_t * spd,
 136                                       ip6_address_t * sa,
 137                                       ip6_address_t * da,
 138                                       u32 spi)
 139 {
 140   ipsec_main_t *im = &ipsec_main;
 141   ipsec_policy_t * p;
 142   ipsec_sa_t * s;
 143   u32 * i;
 144
 145   vec_foreach(i, spd->ipv6_inbound_protect_policy_indices)
 146     {
 147       p = pool_elt_at_index(spd->policies, *i);
 148       s = pool_elt_at_index(im->sad, p->sa_index);
 149
 150       if (spi != s->spi)
 151         continue;
 152
 153       if (s->is_tunnel)
 154         {
 155           if (!ip6_address_is_equal(sa, &s->tunnel_src_addr.ip6))
 156             continue;
 157
 158           if (!ip6_address_is_equal(da, &s->tunnel_dst_addr.ip6))
 159             continue;
 160
 161           return p;
 162         }
 163
 164       if (!ip6_addr_match_range(sa, &p->raddr.start.ip6, &p->raddr.stop.ip6))
 165         continue;
 166
 167       if (!ip6_addr_match_range(da, &p->laddr.start.ip6, &p->laddr.stop.ip6))
 168         continue;
 169
 170       return p;
 171     }
 172     return 0;
 173 }
 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                                      &vnet_buffer (b0)->ip.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) = {
 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
 292 static uword
 293 ipsec_input_ip6_node_fn (vlib_main_t * vm,
 294                          vlib_node_runtime_t * node,
 295                          vlib_frame_t * from_frame)
 296 {
 297   ip6_main_t * i6m = &ip6_main;
 298   ip_lookup_main_t * lm = &i6m->lookup_main;
 299   ip_config_main_t * cm = &lm->rx_config_mains[VNET_UNICAST];
 300   u32 n_left_from, *from, next_index, *to_next;
 301   ipsec_main_t *im = &ipsec_main;
 302
 303   from = vlib_frame_vector_args (from_frame);
 304   n_left_from = from_frame->n_vectors;
 305
 306   next_index = node->cached_next_index;
 307
 308   while (n_left_from > 0)
 309     {
 310       u32 n_left_to_next;
 311
 312       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 313
 314       while (n_left_from > 0 && n_left_to_next > 0)
 315         {
 316           u32 bi0, next0;
 317           vlib_buffer_t * b0;
 318           ip6_header_t *ip0;
 319           esp_header_t *esp0;
 320           ip4_ipsec_config_t * c0;
 321           u32 tunnel_index0 = ~0;
 322           ipsec_spd_t * spd0;
 323           u32 header_size = sizeof(ip0[0]);
 324
 325           bi0 = to_next[0] = from[0];
 326           from += 1;
 327           n_left_from -= 1;
 328           to_next +=1;
 329           n_left_to_next -= 1;
 330
 331           b0 = vlib_get_buffer (vm, bi0);
 332           c0 = vnet_get_config_data (&cm->config_main,
 333                                      &vnet_buffer (b0)->ip.current_config_index,
 334                                      &next0, sizeof (c0[0]));
 335
 336           spd0 = pool_elt_at_index(im->spds, c0->spd_index);
 337
 338           ip0 = vlib_buffer_get_current (b0);
 339           esp0 = (esp_header_t *) ((u8 *) ip0 + header_size);
 340
 341           if (PREDICT_TRUE(ip0->protocol == IP_PROTOCOL_IPSEC_ESP))
 342             {
 343 #if 0
 344               clib_warning("packet received from %U to %U spi %u size %u spd_id %u",
 345                            format_ip6_address, &ip0->src_address,
 346                            format_ip6_address, &ip0->dst_address,
 347                            clib_net_to_host_u32(esp0->spi),
 348                            clib_net_to_host_u16(ip0->payload_length) + header_size,
 349                            spd0->id);
 350 #endif
 351               ipsec_policy_t * p0;
 352               p0 = ipsec_input_ip6_protect_policy_match(spd0,
 353                          &ip0->src_address,
 354                          &ip0->dst_address,
 355                          clib_net_to_host_u32(esp0->spi));
 356
 357               if (PREDICT_TRUE(p0 != 0))
 358                 {
 359                   p0->counter.packets++;
 360                   p0->counter.bytes += clib_net_to_host_u16(ip0->payload_length);
 361                   p0->counter.bytes += header_size;
 362                   vnet_buffer(b0)->output_features.ipsec_sad_index = p0->sa_index;
 363                   next0 = IPSEC_INPUT_NEXT_ESP_DECRYPT;
 364                   vlib_buffer_advance(b0, header_size);
 365                   goto trace0;
 366                 }
 367             }
 368
 369 trace0:
 370           if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED)) {
 371             ipsec_input_trace_t *tr = vlib_add_trace (vm, node, b0, sizeof (*tr));
 372             tr->tunnel_index = tunnel_index0;
 373             tr->spi = clib_host_to_net_u32(esp0->spi);
 374             tr->seq = clib_host_to_net_u32(esp0->seq);
 375           }
 376
 377           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 378                                            n_left_to_next, bi0, next0);
 379         }
 380       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 381     }
 382   vlib_node_increment_counter (vm, ipsec_input_ip6_node.index,
 383                                IPSEC_INPUT_ERROR_RX_PKTS,
 384                                from_frame->n_vectors);
 385
 386   return from_frame->n_vectors;
 387 }
 388
 389
 390 VLIB_REGISTER_NODE (ipsec_input_ip6_node) = {
 391   .function = ipsec_input_ip6_node_fn,
 392   .name = "ipsec-input-ip6",
 393   .vector_size = sizeof (u32),
 394   .format_trace = format_ipsec_input_trace,
 395   .type = VLIB_NODE_TYPE_INTERNAL,
 396
 397   .n_errors = ARRAY_LEN(ipsec_input_error_strings),
 398   .error_strings = ipsec_input_error_strings,
 399
 400   .n_next_nodes = IPSEC_INPUT_N_NEXT,
 401   .next_nodes = {
 402 #define _(s,n) [IPSEC_INPUT_NEXT_##s] = n,
 403     foreach_ipsec_input_next
 404 #undef _
 405   },
 406 };