src/vnet/ipsec/ipsec_output.c

   1 /*
   2  * ipsec_output.c : IPSec output 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/ipsec_io.h>
  24
  25 #define foreach_ipsec_output_error                   \
  26  _(RX_PKTS, "IPSec pkts received")                   \
  27  _(POLICY_DISCARD, "IPSec policy discard")           \
  28  _(POLICY_NO_MATCH, "IPSec policy (no match)")       \
  29  _(POLICY_PROTECT, "IPSec policy protect")           \
  30  _(POLICY_BYPASS, "IPSec policy bypass")             \
  31  _(ENCAPS_FAILED, "IPSec encapsulation failed")
  32
  33 typedef enum
  34 {
  35 #define _(sym,str) IPSEC_OUTPUT_ERROR_##sym,
  36   foreach_ipsec_output_error
  37 #undef _
  38     IPSEC_DECAP_N_ERROR,
  39 } ipsec_output_error_t;
  40
  41 static char *ipsec_output_error_strings[] = {
  42 #define _(sym,string) string,
  43   foreach_ipsec_output_error
  44 #undef _
  45 };
  46
  47 typedef struct
  48 {
  49   u32 spd_id;
  50   u32 policy_id;
  51 } ipsec_output_trace_t;
  52
  53 /* packet trace format function */
  54 static u8 *
  55 format_ipsec_output_trace (u8 * s, va_list * args)
  56 {
  57   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  58   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  59   ipsec_output_trace_t *t = va_arg (*args, ipsec_output_trace_t *);
  60
  61   s = format (s, "spd %u policy %d", t->spd_id, t->policy_id);
  62
  63   return s;
  64 }
  65
  66 always_inline ipsec_policy_t *
  67 ipsec_output_policy_match (ipsec_spd_t * spd, u8 pr, u32 la, u32 ra, u16 lp,
  68                            u16 rp)
  69 {
  70   ipsec_main_t *im = &ipsec_main;
  71   ipsec_policy_t *p;
  72   u32 *i;
  73
  74   if (!spd)
  75     return 0;
  76
  77   vec_foreach (i, spd->policies[IPSEC_SPD_POLICY_IP4_OUTBOUND])
  78   {
  79     p = pool_elt_at_index (im->policies, *i);
  80     if (PREDICT_FALSE (p->protocol && (p->protocol != pr)))
  81       continue;
  82
  83     if (ra < clib_net_to_host_u32 (p->raddr.start.ip4.as_u32))
  84       continue;
  85
  86     if (ra > clib_net_to_host_u32 (p->raddr.stop.ip4.as_u32))
  87       continue;
  88
  89     if (la < clib_net_to_host_u32 (p->laddr.start.ip4.as_u32))
  90       continue;
  91
  92     if (la > clib_net_to_host_u32 (p->laddr.stop.ip4.as_u32))
  93       continue;
  94
  95     if (PREDICT_FALSE
  96         ((pr != IP_PROTOCOL_TCP) && (pr != IP_PROTOCOL_UDP)
  97          && (pr != IP_PROTOCOL_SCTP)))
  98       return p;
  99
 100     if (lp < p->lport.start)
 101       continue;
 102
 103     if (lp > p->lport.stop)
 104       continue;
 105
 106     if (rp < p->rport.start)
 107       continue;
 108
 109     if (rp > p->rport.stop)
 110       continue;
 111
 112     return p;
 113   }
 114   return 0;
 115 }
 116
 117 always_inline uword
 118 ip6_addr_match_range (ip6_address_t * a, ip6_address_t * la,
 119                       ip6_address_t * ua)
 120 {
 121   if ((memcmp (a->as_u64, la->as_u64, 2 * sizeof (u64)) >= 0) &&
 122       (memcmp (a->as_u64, ua->as_u64, 2 * sizeof (u64)) <= 0))
 123     return 1;
 124   return 0;
 125 }
 126
 127 always_inline ipsec_policy_t *
 128 ipsec6_output_policy_match (ipsec_spd_t * spd,
 129                             ip6_address_t * la,
 130                             ip6_address_t * ra, u16 lp, u16 rp, u8 pr)
 131 {
 132   ipsec_main_t *im = &ipsec_main;
 133   ipsec_policy_t *p;
 134   u32 *i;
 135
 136   if (!spd)
 137     return 0;
 138
 139   vec_foreach (i, spd->policies[IPSEC_SPD_POLICY_IP6_OUTBOUND])
 140   {
 141     p = pool_elt_at_index (im->policies, *i);
 142     if (PREDICT_FALSE (p->protocol && (p->protocol != pr)))
 143       continue;
 144
 145     if (!ip6_addr_match_range (ra, &p->raddr.start.ip6, &p->raddr.stop.ip6))
 146       continue;
 147
 148     if (!ip6_addr_match_range (la, &p->laddr.start.ip6, &p->laddr.stop.ip6))
 149       continue;
 150
 151     if (PREDICT_FALSE
 152         ((pr != IP_PROTOCOL_TCP) && (pr != IP_PROTOCOL_UDP)
 153          && (pr != IP_PROTOCOL_SCTP)))
 154       return p;
 155
 156     if (lp < p->lport.start)
 157       continue;
 158
 159     if (lp > p->lport.stop)
 160       continue;
 161
 162     if (rp < p->rport.start)
 163       continue;
 164
 165     if (rp > p->rport.stop)
 166       continue;
 167
 168     return p;
 169   }
 170
 171   return 0;
 172 }
 173
 174 static inline uword
 175 ipsec_output_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
 176                      vlib_frame_t * from_frame, int is_ipv6)
 177 {
 178   ipsec_main_t *im = &ipsec_main;
 179
 180   u32 *from, *to_next = 0, thread_index;
 181   u32 n_left_from, sw_if_index0, last_sw_if_index = (u32) ~ 0;
 182   u32 next_node_index = (u32) ~ 0, last_next_node_index = (u32) ~ 0;
 183   vlib_frame_t *f = 0;
 184   u32 spd_index0 = ~0;
 185   ipsec_spd_t *spd0 = 0;
 186   int bogus;
 187   u64 nc_protect = 0, nc_bypass = 0, nc_discard = 0, nc_nomatch = 0;
 188
 189   from = vlib_frame_vector_args (from_frame);
 190   n_left_from = from_frame->n_vectors;
 191   thread_index = vm->thread_index;
 192
 193   while (n_left_from > 0)
 194     {
 195       u32 bi0, pi0, bi1;
 196       vlib_buffer_t *b0, *b1;
 197       ipsec_policy_t *p0;
 198       ip4_header_t *ip0;
 199       ip6_header_t *ip6_0 = 0;
 200       udp_header_t *udp0;
 201       u32 iph_offset = 0;
 202       tcp_header_t *tcp0;
 203       u64 bytes0;
 204
 205       bi0 = from[0];
 206       b0 = vlib_get_buffer (vm, bi0);
 207       if (n_left_from > 1)
 208         {
 209           bi1 = from[1];
 210           b1 = vlib_get_buffer (vm, bi1);
 211           CLIB_PREFETCH (b1, CLIB_CACHE_LINE_BYTES * 2, STORE);
 212           vlib_prefetch_buffer_data (b1, LOAD);
 213         }
 214       sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_TX];
 215       iph_offset = vnet_buffer (b0)->ip.save_rewrite_length;
 216       ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0)
 217                               + iph_offset);
 218
 219       /* lookup for SPD only if sw_if_index is changed */
 220       if (PREDICT_FALSE (last_sw_if_index != sw_if_index0))
 221         {
 222           uword *p = hash_get (im->spd_index_by_sw_if_index, sw_if_index0);
 223           ALWAYS_ASSERT (p);
 224           spd_index0 = p[0];
 225           spd0 = pool_elt_at_index (im->spds, spd_index0);
 226           last_sw_if_index = sw_if_index0;
 227         }
 228
 229       if (is_ipv6)
 230         {
 231           ip6_0 = (ip6_header_t *) ((u8 *) vlib_buffer_get_current (b0)
 232                                     + iph_offset);
 233
 234           udp0 = ip6_next_header (ip6_0);
 235 #if 0
 236           clib_warning
 237             ("packet received from %U port %u to %U port %u spd_id %u",
 238              format_ip6_address, &ip6_0->src_address,
 239              clib_net_to_host_u16 (udp0->src_port), format_ip6_address,
 240              &ip6_0->dst_address, clib_net_to_host_u16 (udp0->dst_port),
 241              spd0->id);
 242 #endif
 243
 244           p0 = ipsec6_output_policy_match (spd0,
 245                                            &ip6_0->src_address,
 246                                            &ip6_0->dst_address,
 247                                            clib_net_to_host_u16
 248                                            (udp0->src_port),
 249                                            clib_net_to_host_u16
 250                                            (udp0->dst_port), ip6_0->protocol);
 251         }
 252       else
 253         {
 254           udp0 = (udp_header_t *) ((u8 *) ip0 + ip4_header_bytes (ip0));
 255
 256 #if 0
 257           clib_warning ("packet received from %U to %U port %u",
 258                         format_ip4_address, ip0->src_address.as_u8,
 259                         format_ip4_address, ip0->dst_address.as_u8,
 260                         clib_net_to_host_u16 (udp0->dst_port));
 261           clib_warning ("sw_if_index0 %u spd_index0 %u spd_id %u",
 262                         sw_if_index0, spd_index0, spd0->id);
 263 #endif
 264
 265           p0 = ipsec_output_policy_match (spd0, ip0->protocol,
 266                                           clib_net_to_host_u32
 267                                           (ip0->src_address.as_u32),
 268                                           clib_net_to_host_u32
 269                                           (ip0->dst_address.as_u32),
 270                                           clib_net_to_host_u16
 271                                           (udp0->src_port),
 272                                           clib_net_to_host_u16
 273                                           (udp0->dst_port));
 274         }
 275       tcp0 = (void *) udp0;
 276
 277       if (PREDICT_TRUE (p0 != NULL))
 278         {
 279           pi0 = p0 - im->policies;
 280
 281           vlib_prefetch_combined_counter (&ipsec_spd_policy_counters,
 282                                           thread_index, pi0);
 283
 284           if (is_ipv6)
 285             {
 286               bytes0 = clib_net_to_host_u16 (ip6_0->payload_length);
 287               bytes0 += sizeof (ip6_header_t);
 288             }
 289           else
 290             {
 291               bytes0 = clib_net_to_host_u16 (ip0->length);
 292             }
 293
 294           if (p0->policy == IPSEC_POLICY_ACTION_PROTECT)
 295             {
 296               ipsec_sa_t *sa = 0;
 297               nc_protect++;
 298               sa = ipsec_sa_get (p0->sa_index);
 299               if (sa->protocol == IPSEC_PROTOCOL_ESP)
 300                 if (is_ipv6)
 301                   next_node_index = im->esp6_encrypt_node_index;
 302                 else
 303                   next_node_index = im->esp4_encrypt_node_index;
 304               else if (is_ipv6)
 305                 next_node_index = im->ah6_encrypt_node_index;
 306               else
 307                 next_node_index = im->ah4_encrypt_node_index;
 308               vnet_buffer (b0)->ipsec.sad_index = p0->sa_index;
 309
 310               if (PREDICT_FALSE (b0->flags & VNET_BUFFER_F_OFFLOAD))
 311                 {
 312                   u32 oflags = vnet_buffer2 (b0)->oflags;
 313
 314                   /*
 315                    * Clearing offload flags before checksum is computed
 316                    * It guarantees the cache hit!
 317                    */
 318                   vnet_buffer_offload_flags_clear (b0, oflags);
 319
 320                   if (is_ipv6)
 321                     {
 322                       if (PREDICT_FALSE (oflags &
 323                                          VNET_BUFFER_OFFLOAD_F_TCP_CKSUM))
 324                         {
 325                           tcp0->checksum = ip6_tcp_udp_icmp_compute_checksum (
 326                             vm, b0, ip6_0, &bogus);
 327                         }
 328                       if (PREDICT_FALSE (oflags &
 329                                          VNET_BUFFER_OFFLOAD_F_UDP_CKSUM))
 330                         {
 331                           udp0->checksum = ip6_tcp_udp_icmp_compute_checksum (
 332                             vm, b0, ip6_0, &bogus);
 333                         }
 334                     }
 335                   else
 336                     {
 337                       if (PREDICT_FALSE (oflags &
 338                                          VNET_BUFFER_OFFLOAD_F_IP_CKSUM))
 339                         {
 340                           ip0->checksum = ip4_header_checksum (ip0);
 341                         }
 342                       if (PREDICT_FALSE (oflags &
 343                                          VNET_BUFFER_OFFLOAD_F_TCP_CKSUM))
 344                         {
 345                           tcp0->checksum =
 346                             ip4_tcp_udp_compute_checksum (vm, b0, ip0);
 347                         }
 348                       if (PREDICT_FALSE (oflags &
 349                                          VNET_BUFFER_OFFLOAD_F_UDP_CKSUM))
 350                         {
 351                           udp0->checksum =
 352                             ip4_tcp_udp_compute_checksum (vm, b0, ip0);
 353                         }
 354                     }
 355                 }
 356               vlib_buffer_advance (b0, iph_offset);
 357             }
 358           else if (p0->policy == IPSEC_POLICY_ACTION_BYPASS)
 359             {
 360               nc_bypass++;
 361               next_node_index = get_next_output_feature_node_index (b0, node);
 362             }
 363           else
 364             {
 365               nc_discard++;
 366               next_node_index = im->error_drop_node_index;
 367             }
 368           vlib_increment_combined_counter
 369             (&ipsec_spd_policy_counters, thread_index, pi0, 1, bytes0);
 370         }
 371       else
 372         {
 373           pi0 = ~0;
 374           nc_nomatch++;
 375           next_node_index = im->error_drop_node_index;
 376         }
 377
 378       from += 1;
 379       n_left_from -= 1;
 380
 381       if (PREDICT_FALSE ((last_next_node_index != next_node_index) || f == 0))
 382         {
 383           /* if this is not 1st frame */
 384           if (f)
 385             vlib_put_frame_to_node (vm, last_next_node_index, f);
 386
 387           last_next_node_index = next_node_index;
 388
 389           f = vlib_get_frame_to_node (vm, next_node_index);
 390
 391           /* frame->frame_flags, copy it from node */
 392           /* Copy trace flag from next_frame and from runtime. */
 393           f->frame_flags |= node->flags & VLIB_NODE_FLAG_TRACE;
 394
 395           to_next = vlib_frame_vector_args (f);
 396         }
 397
 398       to_next[0] = bi0;
 399       to_next += 1;
 400       f->n_vectors++;
 401
 402       if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE) &&
 403           PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 404         {
 405           ipsec_output_trace_t *tr =
 406             vlib_add_trace (vm, node, b0, sizeof (*tr));
 407           if (spd0)
 408             tr->spd_id = spd0->id;
 409           tr->policy_id = pi0;
 410         }
 411     }
 412
 413   vlib_put_frame_to_node (vm, next_node_index, f);
 414   vlib_node_increment_counter (vm, node->node_index,
 415                                IPSEC_OUTPUT_ERROR_POLICY_PROTECT, nc_protect);
 416   vlib_node_increment_counter (vm, node->node_index,
 417                                IPSEC_OUTPUT_ERROR_POLICY_BYPASS, nc_bypass);
 418   vlib_node_increment_counter (vm, node->node_index,
 419                                IPSEC_OUTPUT_ERROR_POLICY_DISCARD, nc_discard);
 420   vlib_node_increment_counter (vm, node->node_index,
 421                                IPSEC_OUTPUT_ERROR_POLICY_NO_MATCH,
 422                                nc_nomatch);
 423   return from_frame->n_vectors;
 424 }
 425
 426 VLIB_NODE_FN (ipsec4_output_node) (vlib_main_t * vm,
 427                                    vlib_node_runtime_t * node,
 428                                    vlib_frame_t * frame)
 429 {
 430   return ipsec_output_inline (vm, node, frame, 0);
 431 }
 432
 433 /* *INDENT-OFF* */
 434 VLIB_REGISTER_NODE (ipsec4_output_node) = {
 435   .name = "ipsec4-output-feature",
 436   .vector_size = sizeof (u32),
 437   .format_trace = format_ipsec_output_trace,
 438   .type = VLIB_NODE_TYPE_INTERNAL,
 439
 440   .n_errors = ARRAY_LEN(ipsec_output_error_strings),
 441   .error_strings = ipsec_output_error_strings,
 442
 443   .n_next_nodes = IPSEC_OUTPUT_N_NEXT,
 444   .next_nodes = {
 445 #define _(s,n) [IPSEC_OUTPUT_NEXT_##s] = n,
 446     foreach_ipsec_output_next
 447 #undef _
 448   },
 449 };
 450 /* *INDENT-ON* */
 451
 452 VLIB_NODE_FN (ipsec6_output_node) (vlib_main_t * vm,
 453                                    vlib_node_runtime_t * node,
 454                                    vlib_frame_t * frame)
 455 {
 456   return ipsec_output_inline (vm, node, frame, 1);
 457 }
 458
 459 VLIB_REGISTER_NODE (ipsec6_output_node) = {
 460   .name = "ipsec6-output-feature",
 461   .vector_size = sizeof (u32),
 462   .format_trace = format_ipsec_output_trace,
 463   .type = VLIB_NODE_TYPE_INTERNAL,
 464
 465   .n_errors = ARRAY_LEN(ipsec_output_error_strings),
 466   .error_strings = ipsec_output_error_strings,
 467
 468   .n_next_nodes = IPSEC_OUTPUT_N_NEXT,
 469   .next_nodes = {
 470 #define _(s,n) [IPSEC_OUTPUT_NEXT_##s] = n,
 471     foreach_ipsec_output_next
 472 #undef _
 473   },
 474 };
 475