src/vnet/ip/ip4_forward.c

   1 /*
   2  * Copyright (c) 2015 Cisco and/or its affiliates.
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  */
  15 /*
  16  * ip/ip4_forward.c: IP v4 forwarding
  17  *
  18  * Copyright (c) 2008 Eliot Dresselhaus
  19  *
  20  * Permission is hereby granted, free of charge, to any person obtaining
  21  * a copy of this software and associated documentation files (the
  22  * "Software"), to deal in the Software without restriction, including
  23  * without limitation the rights to use, copy, modify, merge, publish,
  24  * distribute, sublicense, and/or sell copies of the Software, and to
  25  * permit persons to whom the Software is furnished to do so, subject to
  26  * the following conditions:
  27  *
  28  * The above copyright notice and this permission notice shall be
  29  * included in all copies or substantial portions of the Software.
  30  *
  31  *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  32  *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  33  *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  34  *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  35  *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  36  *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  37  *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  38  */
  39
  40 #include <vnet/vnet.h>
  41 #include <vnet/ip/ip.h>
  42 #include <vnet/ip/ip_frag.h>
  43 #include <vnet/ethernet/ethernet.h>     /* for ethernet_header_t */
  44 #include <vnet/ethernet/arp_packet.h>   /* for ethernet_arp_header_t */
  45 #include <vnet/ppp/ppp.h>
  46 #include <vnet/srp/srp.h>       /* for srp_hw_interface_class */
  47 #include <vnet/api_errno.h>     /* for API error numbers */
  48 #include <vnet/fib/fib_table.h> /* for FIB table and entry creation */
  49 #include <vnet/fib/fib_entry.h> /* for FIB table and entry creation */
  50 #include <vnet/fib/fib_urpf_list.h>     /* for FIB uRPF check */
  51 #include <vnet/fib/ip4_fib.h>
  52 #include <vnet/mfib/ip4_mfib.h>
  53 #include <vnet/dpo/load_balance.h>
  54 #include <vnet/dpo/load_balance_map.h>
  55 #include <vnet/dpo/receive_dpo.h>
  56 #include <vnet/dpo/classify_dpo.h>
  57 #include <vnet/mfib/mfib_table.h>       /* for mFIB table and entry creation */
  58 #include <vnet/adj/adj_dp.h>
  59 #include <vnet/pg/pg.h>
  60
  61 #include <vnet/ip/ip4_forward.h>
  62 #include <vnet/interface_output.h>
  63 #include <vnet/classify/vnet_classify.h>
  64 #include <vnet/ip/reass/ip4_full_reass.h>
  65
  66 /** @brief IPv4 lookup node.
  67     @node ip4-lookup
  68
  69     This is the main IPv4 lookup dispatch node.
  70
  71     @param vm vlib_main_t corresponding to the current thread
  72     @param node vlib_node_runtime_t
  73     @param frame vlib_frame_t whose contents should be dispatched
  74
  75     @par Graph mechanics: buffer metadata, next index usage
  76
  77     @em Uses:
  78     - <code>vnet_buffer(b)->sw_if_index[VLIB_RX]</code>
  79         - Indicates the @c sw_if_index value of the interface that the
  80           packet was received on.
  81     - <code>vnet_buffer(b)->sw_if_index[VLIB_TX]</code>
  82         - When the value is @c ~0 then the node performs a longest prefix
  83           match (LPM) for the packet destination address in the FIB attached
  84           to the receive interface.
  85         - Otherwise perform LPM for the packet destination address in the
  86           indicated FIB. In this case <code>[VLIB_TX]</code> is a FIB index
  87           value (0, 1, ...) and not a VRF id.
  88
  89     @em Sets:
  90     - <code>vnet_buffer(b)->ip.adj_index[VLIB_TX]</code>
  91         - The lookup result adjacency index.
  92
  93     <em>Next Index:</em>
  94     - Dispatches the packet to the node index found in
  95       ip_adjacency_t @c adj->lookup_next_index
  96       (where @c adj is the lookup result adjacency).
  97 */
  98 VLIB_NODE_FN (ip4_lookup_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
  99                                 vlib_frame_t * frame)
 100 {
 101   return ip4_lookup_inline (vm, node, frame);
 102 }
 103
 104 static u8 *format_ip4_lookup_trace (u8 * s, va_list * args);
 105
 106 /* *INDENT-OFF* */
 107 VLIB_REGISTER_NODE (ip4_lookup_node) =
 108 {
 109   .name = "ip4-lookup",
 110   .vector_size = sizeof (u32),
 111   .format_trace = format_ip4_lookup_trace,
 112   .n_next_nodes = IP_LOOKUP_N_NEXT,
 113   .next_nodes = IP4_LOOKUP_NEXT_NODES,
 114 };
 115 /* *INDENT-ON* */
 116
 117 VLIB_NODE_FN (ip4_load_balance_node) (vlib_main_t * vm,
 118                                       vlib_node_runtime_t * node,
 119                                       vlib_frame_t * frame)
 120 {
 121   vlib_combined_counter_main_t *cm = &load_balance_main.lbm_via_counters;
 122   u32 n_left, *from;
 123   u32 thread_index = vm->thread_index;
 124   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
 125   u16 nexts[VLIB_FRAME_SIZE], *next;
 126
 127   from = vlib_frame_vector_args (frame);
 128   n_left = frame->n_vectors;
 129   next = nexts;
 130
 131   vlib_get_buffers (vm, from, bufs, n_left);
 132
 133   while (n_left >= 4)
 134     {
 135       const load_balance_t *lb0, *lb1;
 136       const ip4_header_t *ip0, *ip1;
 137       u32 lbi0, hc0, lbi1, hc1;
 138       const dpo_id_t *dpo0, *dpo1;
 139
 140       /* Prefetch next iteration. */
 141       {
 142         vlib_prefetch_buffer_header (b[2], LOAD);
 143         vlib_prefetch_buffer_header (b[3], LOAD);
 144
 145         CLIB_PREFETCH (b[2]->data, sizeof (ip0[0]), LOAD);
 146         CLIB_PREFETCH (b[3]->data, sizeof (ip0[0]), LOAD);
 147       }
 148
 149       ip0 = vlib_buffer_get_current (b[0]);
 150       ip1 = vlib_buffer_get_current (b[1]);
 151       lbi0 = vnet_buffer (b[0])->ip.adj_index[VLIB_TX];
 152       lbi1 = vnet_buffer (b[1])->ip.adj_index[VLIB_TX];
 153
 154       lb0 = load_balance_get (lbi0);
 155       lb1 = load_balance_get (lbi1);
 156
 157       /*
 158        * this node is for via FIBs we can re-use the hash value from the
 159        * to node if present.
 160        * We don't want to use the same hash value at each level in the recursion
 161        * graph as that would lead to polarisation
 162        */
 163       hc0 = hc1 = 0;
 164
 165       if (PREDICT_FALSE (lb0->lb_n_buckets > 1))
 166         {
 167           if (PREDICT_TRUE (vnet_buffer (b[0])->ip.flow_hash))
 168             {
 169               hc0 = vnet_buffer (b[0])->ip.flow_hash =
 170                 vnet_buffer (b[0])->ip.flow_hash >> 1;
 171             }
 172           else
 173             {
 174               hc0 = vnet_buffer (b[0])->ip.flow_hash =
 175                 ip4_compute_flow_hash (ip0, lb0->lb_hash_config);
 176             }
 177           dpo0 = load_balance_get_fwd_bucket
 178             (lb0, (hc0 & (lb0->lb_n_buckets_minus_1)));
 179         }
 180       else
 181         {
 182           dpo0 = load_balance_get_bucket_i (lb0, 0);
 183         }
 184       if (PREDICT_FALSE (lb1->lb_n_buckets > 1))
 185         {
 186           if (PREDICT_TRUE (vnet_buffer (b[1])->ip.flow_hash))
 187             {
 188               hc1 = vnet_buffer (b[1])->ip.flow_hash =
 189                 vnet_buffer (b[1])->ip.flow_hash >> 1;
 190             }
 191           else
 192             {
 193               hc1 = vnet_buffer (b[1])->ip.flow_hash =
 194                 ip4_compute_flow_hash (ip1, lb1->lb_hash_config);
 195             }
 196           dpo1 = load_balance_get_fwd_bucket
 197             (lb1, (hc1 & (lb1->lb_n_buckets_minus_1)));
 198         }
 199       else
 200         {
 201           dpo1 = load_balance_get_bucket_i (lb1, 0);
 202         }
 203
 204       next[0] = dpo0->dpoi_next_node;
 205       next[1] = dpo1->dpoi_next_node;
 206
 207       vnet_buffer (b[0])->ip.adj_index[VLIB_TX] = dpo0->dpoi_index;
 208       vnet_buffer (b[1])->ip.adj_index[VLIB_TX] = dpo1->dpoi_index;
 209
 210       vlib_increment_combined_counter
 211         (cm, thread_index, lbi0, 1, vlib_buffer_length_in_chain (vm, b[0]));
 212       vlib_increment_combined_counter
 213         (cm, thread_index, lbi1, 1, vlib_buffer_length_in_chain (vm, b[1]));
 214
 215       b += 2;
 216       next += 2;
 217       n_left -= 2;
 218     }
 219
 220   while (n_left > 0)
 221     {
 222       const load_balance_t *lb0;
 223       const ip4_header_t *ip0;
 224       const dpo_id_t *dpo0;
 225       u32 lbi0, hc0;
 226
 227       ip0 = vlib_buffer_get_current (b[0]);
 228       lbi0 = vnet_buffer (b[0])->ip.adj_index[VLIB_TX];
 229
 230       lb0 = load_balance_get (lbi0);
 231
 232       hc0 = 0;
 233       if (PREDICT_FALSE (lb0->lb_n_buckets > 1))
 234         {
 235           if (PREDICT_TRUE (vnet_buffer (b[0])->ip.flow_hash))
 236             {
 237               hc0 = vnet_buffer (b[0])->ip.flow_hash =
 238                 vnet_buffer (b[0])->ip.flow_hash >> 1;
 239             }
 240           else
 241             {
 242               hc0 = vnet_buffer (b[0])->ip.flow_hash =
 243                 ip4_compute_flow_hash (ip0, lb0->lb_hash_config);
 244             }
 245           dpo0 = load_balance_get_fwd_bucket
 246             (lb0, (hc0 & (lb0->lb_n_buckets_minus_1)));
 247         }
 248       else
 249         {
 250           dpo0 = load_balance_get_bucket_i (lb0, 0);
 251         }
 252
 253       next[0] = dpo0->dpoi_next_node;
 254       vnet_buffer (b[0])->ip.adj_index[VLIB_TX] = dpo0->dpoi_index;
 255
 256       vlib_increment_combined_counter
 257         (cm, thread_index, lbi0, 1, vlib_buffer_length_in_chain (vm, b[0]));
 258
 259       b += 1;
 260       next += 1;
 261       n_left -= 1;
 262     }
 263
 264   vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
 265   if (node->flags & VLIB_NODE_FLAG_TRACE)
 266     ip4_forward_next_trace (vm, node, frame, VLIB_TX);
 267
 268   return frame->n_vectors;
 269 }
 270
 271 /* *INDENT-OFF* */
 272 VLIB_REGISTER_NODE (ip4_load_balance_node) =
 273 {
 274   .name = "ip4-load-balance",
 275   .vector_size = sizeof (u32),
 276   .sibling_of = "ip4-lookup",
 277   .format_trace = format_ip4_lookup_trace,
 278 };
 279 /* *INDENT-ON* */
 280
 281 #ifndef CLIB_MARCH_VARIANT
 282 /* get first interface address */
 283 ip4_address_t *
 284 ip4_interface_first_address (ip4_main_t * im, u32 sw_if_index,
 285                              ip_interface_address_t ** result_ia)
 286 {
 287   ip_lookup_main_t *lm = &im->lookup_main;
 288   ip_interface_address_t *ia = 0;
 289   ip4_address_t *result = 0;
 290
 291   /* *INDENT-OFF* */
 292   foreach_ip_interface_address
 293     (lm, ia, sw_if_index,
 294      1 /* honor unnumbered */ ,
 295      ({
 296        ip4_address_t * a =
 297          ip_interface_address_get_address (lm, ia);
 298        result = a;
 299        break;
 300      }));
 301   /* *INDENT-OFF* */
 302   if (result_ia)
 303     *result_ia = result ? ia : 0;
 304   return result;
 305 }
 306 #endif
 307
 308 static void
 309 ip4_add_subnet_bcast_route (u32 fib_index,
 310                             fib_prefix_t *pfx,
 311                             u32 sw_if_index)
 312 {
 313   vnet_sw_interface_flags_t iflags;
 314
 315   iflags = vnet_sw_interface_get_flags(vnet_get_main(), sw_if_index);
 316
 317   fib_table_entry_special_remove(fib_index,
 318                                  pfx,
 319                                  FIB_SOURCE_INTERFACE);
 320
 321   if (iflags & VNET_SW_INTERFACE_FLAG_DIRECTED_BCAST)
 322     {
 323       fib_table_entry_update_one_path (fib_index, pfx,
 324                                        FIB_SOURCE_INTERFACE,
 325                                        FIB_ENTRY_FLAG_NONE,
 326                                        DPO_PROTO_IP4,
 327                                        /* No next-hop address */
 328                                        &ADJ_BCAST_ADDR,
 329                                        sw_if_index,
 330                                        // invalid FIB index
 331                                        ~0,
 332                                        1,
 333                                        // no out-label stack
 334                                        NULL,
 335                                        FIB_ROUTE_PATH_FLAG_NONE);
 336     }
 337   else
 338     {
 339         fib_table_entry_special_add(fib_index,
 340                                     pfx,
 341                                     FIB_SOURCE_INTERFACE,
 342                                     (FIB_ENTRY_FLAG_DROP |
 343                                      FIB_ENTRY_FLAG_LOOSE_URPF_EXEMPT));
 344     }
 345 }
 346
 347 static void
 348 ip4_add_interface_prefix_routes (ip4_main_t *im,
 349                                  u32 sw_if_index,
 350                                  u32 fib_index,
 351                                  ip_interface_address_t * a)
 352 {
 353   ip_lookup_main_t *lm = &im->lookup_main;
 354   ip_interface_prefix_t *if_prefix;
 355   ip4_address_t *address = ip_interface_address_get_address (lm, a);
 356
 357   ip_interface_prefix_key_t key = {
 358     .prefix = {
 359       .fp_len = a->address_length,
 360       .fp_proto = FIB_PROTOCOL_IP4,
 361       .fp_addr.ip4.as_u32 = address->as_u32 & im->fib_masks[a->address_length],
 362     },
 363     .sw_if_index = sw_if_index,
 364   };
 365
 366   fib_prefix_t pfx_special = {
 367     .fp_proto = FIB_PROTOCOL_IP4,
 368   };
 369
 370   /* If prefix already set on interface, just increment ref count & return */
 371   if_prefix = ip_get_interface_prefix (lm, &key);
 372   if (if_prefix)
 373     {
 374       if_prefix->ref_count += 1;
 375       return;
 376     }
 377
 378   /* New prefix - allocate a pool entry, initialize it, add to the hash */
 379   pool_get (lm->if_prefix_pool, if_prefix);
 380   if_prefix->ref_count = 1;
 381   if_prefix->src_ia_index = a - lm->if_address_pool;
 382   clib_memcpy (&if_prefix->key, &key, sizeof (key));
 383   mhash_set (&lm->prefix_to_if_prefix_index, &key,
 384              if_prefix - lm->if_prefix_pool, 0 /* old value */);
 385
 386   pfx_special.fp_len = a->address_length;
 387   pfx_special.fp_addr.ip4.as_u32 = address->as_u32;
 388
 389   /* set the glean route for the prefix */
 390   fib_table_entry_update_one_path (fib_index, &pfx_special,
 391                                    FIB_SOURCE_INTERFACE,
 392                                    (FIB_ENTRY_FLAG_CONNECTED |
 393                                     FIB_ENTRY_FLAG_ATTACHED),
 394                                    DPO_PROTO_IP4,
 395                                    /* No next-hop address */
 396                                    NULL,
 397                                    sw_if_index,
 398                                    /* invalid FIB index */
 399                                    ~0,
 400                                    1,
 401                                    /* no out-label stack */
 402                                    NULL,
 403                                    FIB_ROUTE_PATH_FLAG_NONE);
 404
 405   /* length <= 30 - add glean, drop first address, maybe drop bcast address */
 406   if (a->address_length <= 30)
 407     {
 408       /* set a drop route for the base address of the prefix */
 409       pfx_special.fp_len = 32;
 410       pfx_special.fp_addr.ip4.as_u32 =
 411         address->as_u32 & im->fib_masks[a->address_length];
 412
 413       if (pfx_special.fp_addr.ip4.as_u32 != address->as_u32)
 414         fib_table_entry_special_add (fib_index, &pfx_special,
 415                                      FIB_SOURCE_INTERFACE,
 416                                      (FIB_ENTRY_FLAG_DROP |
 417                                       FIB_ENTRY_FLAG_LOOSE_URPF_EXEMPT));
 418
 419       /* set a route for the broadcast address of the prefix */
 420       pfx_special.fp_len = 32;
 421       pfx_special.fp_addr.ip4.as_u32 =
 422         address->as_u32 | ~im->fib_masks[a->address_length];
 423       if (pfx_special.fp_addr.ip4.as_u32 != address->as_u32)
 424         ip4_add_subnet_bcast_route (fib_index, &pfx_special, sw_if_index);
 425
 426
 427     }
 428   /* length == 31 - add an attached route for the other address */
 429   else if (a->address_length == 31)
 430     {
 431       pfx_special.fp_len = 32;
 432       pfx_special.fp_addr.ip4.as_u32 =
 433         address->as_u32 ^ clib_host_to_net_u32(1);
 434
 435       fib_table_entry_update_one_path (fib_index, &pfx_special,
 436                                        FIB_SOURCE_INTERFACE,
 437                                        (FIB_ENTRY_FLAG_ATTACHED),
 438                                        DPO_PROTO_IP4,
 439                                        &pfx_special.fp_addr,
 440                                        sw_if_index,
 441                                        /* invalid FIB index */
 442                                        ~0,
 443                                        1,
 444                                        NULL,
 445                                        FIB_ROUTE_PATH_FLAG_NONE);
 446     }
 447 }
 448
 449 static void
 450 ip4_add_interface_routes (u32 sw_if_index,
 451                           ip4_main_t * im, u32 fib_index,
 452                           ip_interface_address_t * a)
 453 {
 454   ip_lookup_main_t *lm = &im->lookup_main;
 455   ip4_address_t *address = ip_interface_address_get_address (lm, a);
 456   fib_prefix_t pfx = {
 457     .fp_len = 32,
 458     .fp_proto = FIB_PROTOCOL_IP4,
 459     .fp_addr.ip4 = *address,
 460   };
 461
 462   /* set special routes for the prefix if needed */
 463   ip4_add_interface_prefix_routes (im, sw_if_index, fib_index, a);
 464
 465   if (sw_if_index < vec_len (lm->classify_table_index_by_sw_if_index))
 466     {
 467       u32 classify_table_index =
 468         lm->classify_table_index_by_sw_if_index[sw_if_index];
 469       if (classify_table_index != (u32) ~ 0)
 470         {
 471           dpo_id_t dpo = DPO_INVALID;
 472
 473           dpo_set (&dpo,
 474                    DPO_CLASSIFY,
 475                    DPO_PROTO_IP4,
 476                    classify_dpo_create (DPO_PROTO_IP4, classify_table_index));
 477
 478           fib_table_entry_special_dpo_add (fib_index,
 479                                            &pfx,
 480                                            FIB_SOURCE_CLASSIFY,
 481                                            FIB_ENTRY_FLAG_NONE, &dpo);
 482           dpo_reset (&dpo);
 483         }
 484     }
 485
 486   fib_table_entry_update_one_path (fib_index, &pfx,
 487                                    FIB_SOURCE_INTERFACE,
 488                                    (FIB_ENTRY_FLAG_CONNECTED |
 489                                     FIB_ENTRY_FLAG_LOCAL),
 490                                    DPO_PROTO_IP4,
 491                                    &pfx.fp_addr,
 492                                    sw_if_index,
 493                                    // invalid FIB index
 494                                    ~0,
 495                                    1, NULL,
 496                                    FIB_ROUTE_PATH_FLAG_NONE);
 497 }
 498
 499 static void
 500 ip4_del_interface_prefix_routes (ip4_main_t * im,
 501                                  u32 sw_if_index,
 502                                  u32 fib_index,
 503                                  ip4_address_t * address,
 504                                  u32 address_length)
 505 {
 506   ip_lookup_main_t *lm = &im->lookup_main;
 507   ip_interface_prefix_t *if_prefix;
 508
 509   ip_interface_prefix_key_t key = {
 510     .prefix = {
 511       .fp_len = address_length,
 512       .fp_proto = FIB_PROTOCOL_IP4,
 513       .fp_addr.ip4.as_u32 = address->as_u32 & im->fib_masks[address_length],
 514     },
 515     .sw_if_index = sw_if_index,
 516   };
 517
 518   fib_prefix_t pfx_special = {
 519     .fp_len = 32,
 520     .fp_proto = FIB_PROTOCOL_IP4,
 521   };
 522
 523   if_prefix = ip_get_interface_prefix (lm, &key);
 524   if (!if_prefix)
 525     {
 526       clib_warning ("Prefix not found while deleting %U",
 527                     format_ip4_address_and_length, address, address_length);
 528       return;
 529     }
 530
 531   if_prefix->ref_count -= 1;
 532
 533   /*
 534    * Routes need to be adjusted if deleting last intf addr in prefix
 535    *
 536    * We're done now otherwise
 537    */
 538   if (if_prefix->ref_count > 0)
 539     return;
 540
 541   /* length <= 30, delete glean route, first address, last address */
 542   if (address_length <= 30)
 543     {
 544       /* Less work to do in FIB if we remove the covered /32s first */
 545
 546       /* first address in prefix */
 547       pfx_special.fp_addr.ip4.as_u32 =
 548         address->as_u32 & im->fib_masks[address_length];
 549       pfx_special.fp_len = 32;
 550
 551       if (pfx_special.fp_addr.ip4.as_u32 != address->as_u32)
 552         fib_table_entry_special_remove (fib_index,
 553                                         &pfx_special,
 554                                         FIB_SOURCE_INTERFACE);
 555
 556       /* prefix broadcast address */
 557       pfx_special.fp_addr.ip4.as_u32 =
 558         address->as_u32 | ~im->fib_masks[address_length];
 559       pfx_special.fp_len = 32;
 560
 561       if (pfx_special.fp_addr.ip4.as_u32 != address->as_u32)
 562         fib_table_entry_special_remove (fib_index,
 563                                         &pfx_special,
 564                                         FIB_SOURCE_INTERFACE);
 565     }
 566   else if (address_length == 31)
 567     {
 568       /* length == 31, delete attached route for the other address */
 569       pfx_special.fp_addr.ip4.as_u32 =
 570         address->as_u32 ^ clib_host_to_net_u32(1);
 571
 572       fib_table_entry_delete (fib_index, &pfx_special, FIB_SOURCE_INTERFACE);
 573     }
 574
 575   /* remove glean route for prefix */
 576   pfx_special.fp_addr.ip4 = *address;
 577   pfx_special.fp_len = address_length;
 578   fib_table_entry_delete (fib_index, &pfx_special, FIB_SOURCE_INTERFACE);
 579
 580   mhash_unset (&lm->prefix_to_if_prefix_index, &key, 0 /* old_value */);
 581   pool_put (lm->if_prefix_pool, if_prefix);
 582 }
 583
 584 static void
 585 ip4_del_interface_routes (u32 sw_if_index,
 586                           ip4_main_t * im,
 587                           u32 fib_index,
 588                           ip4_address_t * address, u32 address_length)
 589 {
 590   fib_prefix_t pfx = {
 591     .fp_len = 32,
 592     .fp_proto = FIB_PROTOCOL_IP4,
 593     .fp_addr.ip4 = *address,
 594   };
 595
 596   fib_table_entry_delete (fib_index, &pfx, FIB_SOURCE_INTERFACE);
 597
 598   ip4_del_interface_prefix_routes (im, sw_if_index, fib_index,
 599                                    address, address_length);
 600 }
 601
 602 #ifndef CLIB_MARCH_VARIANT
 603 void
 604 ip4_sw_interface_enable_disable (u32 sw_if_index, u32 is_enable)
 605 {
 606   ip4_main_t *im = &ip4_main;
 607   vnet_main_t *vnm = vnet_get_main ();
 608   vnet_hw_interface_t *hi = vnet_get_sup_hw_interface (vnm, sw_if_index);
 609
 610   vec_validate_init_empty (im->ip_enabled_by_sw_if_index, sw_if_index, 0);
 611
 612   /*
 613    * enable/disable only on the 1<->0 transition
 614    */
 615   if (is_enable)
 616     {
 617       if (1 != ++im->ip_enabled_by_sw_if_index[sw_if_index])
 618         return;
 619     }
 620   else
 621     {
 622       ASSERT (im->ip_enabled_by_sw_if_index[sw_if_index] > 0);
 623       if (0 != --im->ip_enabled_by_sw_if_index[sw_if_index])
 624         return;
 625     }
 626   vnet_feature_enable_disable ("ip4-unicast", "ip4-not-enabled", sw_if_index,
 627                                !is_enable, 0, 0);
 628
 629
 630   vnet_feature_enable_disable ("ip4-multicast", "ip4-not-enabled",
 631                                sw_if_index, !is_enable, 0, 0);
 632
 633   if (is_enable)
 634     hi->l3_if_count++;
 635   else if (hi->l3_if_count)
 636     hi->l3_if_count--;
 637
 638   {
 639     ip4_enable_disable_interface_callback_t *cb;
 640     vec_foreach (cb, im->enable_disable_interface_callbacks)
 641       cb->function (im, cb->function_opaque, sw_if_index, is_enable);
 642   }
 643 }
 644
 645 static clib_error_t *
 646 ip4_add_del_interface_address_internal (vlib_main_t * vm,
 647                                         u32 sw_if_index,
 648                                         ip4_address_t * address,
 649                                         u32 address_length, u32 is_del)
 650 {
 651   vnet_main_t *vnm = vnet_get_main ();
 652   ip4_main_t *im = &ip4_main;
 653   ip_lookup_main_t *lm = &im->lookup_main;
 654   clib_error_t *error = 0;
 655   u32 if_address_index;
 656   ip4_address_fib_t ip4_af, *addr_fib = 0;
 657
 658   error = vnet_sw_interface_supports_addressing (vnm, sw_if_index);
 659   if (error)
 660     {
 661       vnm->api_errno = VNET_API_ERROR_UNSUPPORTED;
 662       return error;
 663     }
 664
 665   ip4_addr_fib_init (&ip4_af, address,
 666                      vec_elt (im->fib_index_by_sw_if_index, sw_if_index));
 667   vec_add1 (addr_fib, ip4_af);
 668
 669   /*
 670    * there is no support for adj-fib handling in the presence of overlapping
 671    * subnets on interfaces. Easy fix - disallow overlapping subnets, like
 672    * most routers do.
 673    */
 674   /* *INDENT-OFF* */
 675   if (!is_del)
 676     {
 677       /* When adding an address check that it does not conflict
 678          with an existing address on any interface in this table. */
 679       ip_interface_address_t *ia;
 680       vnet_sw_interface_t *sif;
 681
 682       pool_foreach (sif, vnm->interface_main.sw_interfaces)
 683        {
 684           if (im->fib_index_by_sw_if_index[sw_if_index] ==
 685               im->fib_index_by_sw_if_index[sif->sw_if_index])
 686             {
 687               foreach_ip_interface_address
 688                 (&im->lookup_main, ia, sif->sw_if_index,
 689                  0 /* honor unnumbered */ ,
 690                  ({
 691                    ip4_address_t * x =
 692                      ip_interface_address_get_address
 693                      (&im->lookup_main, ia);
 694
 695                    if (ip4_destination_matches_route
 696                        (im, address, x, ia->address_length) ||
 697                        ip4_destination_matches_route (im,
 698                                                       x,
 699                                                       address,
 700                                                       address_length))
 701                      {
 702                        /* an intf may have >1 addr from the same prefix */
 703                        if ((sw_if_index == sif->sw_if_index) &&
 704                            (ia->address_length == address_length) &&
 705                            (x->as_u32 != address->as_u32))
 706                          continue;
 707
 708                        if (ia->flags & IP_INTERFACE_ADDRESS_FLAG_STALE)
 709                          /* if the address we're comparing against is stale
 710                           * then the CP has not added this one back yet, maybe
 711                           * it never will, so we have to assume it won't and
 712                           * ignore it. if it does add it back, then it will fail
 713                           * because this one is now present */
 714                          continue;
 715
 716                        /* error if the length or intf was different */
 717                        vnm->api_errno = VNET_API_ERROR_ADDRESS_IN_USE;
 718
 719                        error = clib_error_create
 720                          ("failed to add %U on %U which conflicts with %U for interface %U",
 721                           format_ip4_address_and_length, address,
 722                           address_length,
 723                           format_vnet_sw_if_index_name, vnm,
 724                           sw_if_index,
 725                           format_ip4_address_and_length, x,
 726                           ia->address_length,
 727                           format_vnet_sw_if_index_name, vnm,
 728                           sif->sw_if_index);
 729                        goto done;
 730                      }
 731                  }));
 732             }
 733       }
 734     }
 735   /* *INDENT-ON* */
 736
 737   if_address_index = ip_interface_address_find (lm, addr_fib, address_length);
 738
 739   if (is_del)
 740     {
 741       if (~0 == if_address_index)
 742         {
 743           vnm->api_errno = VNET_API_ERROR_ADDRESS_NOT_FOUND_FOR_INTERFACE;
 744           error = clib_error_create ("%U not found for interface %U",
 745                                      lm->format_address_and_length,
 746                                      addr_fib, address_length,
 747                                      format_vnet_sw_if_index_name, vnm,
 748                                      sw_if_index);
 749           goto done;
 750         }
 751
 752       error = ip_interface_address_del (lm, vnm, if_address_index, addr_fib,
 753                                         address_length, sw_if_index);
 754       if (error)
 755         goto done;
 756     }
 757   else
 758     {
 759       if (~0 != if_address_index)
 760         {
 761           ip_interface_address_t *ia;
 762
 763           ia = pool_elt_at_index (lm->if_address_pool, if_address_index);
 764
 765           if (ia->flags & IP_INTERFACE_ADDRESS_FLAG_STALE)
 766             {
 767               if (ia->sw_if_index == sw_if_index)
 768                 {
 769                   /* re-adding an address during the replace action.
 770                    * consdier this the update. clear the flag and
 771                    * we're done */
 772                   ia->flags &= ~IP_INTERFACE_ADDRESS_FLAG_STALE;
 773                   goto done;
 774                 }
 775               else
 776                 {
 777                   /* The prefix is moving from one interface to another.
 778                    * delete the stale and add the new */
 779                   ip4_add_del_interface_address_internal (vm,
 780                                                           ia->sw_if_index,
 781                                                           address,
 782                                                           address_length, 1);
 783                   ia = NULL;
 784                   error = ip_interface_address_add (lm, sw_if_index,
 785                                                     addr_fib, address_length,
 786                                                     &if_address_index);
 787                 }
 788             }
 789           else
 790             {
 791               vnm->api_errno = VNET_API_ERROR_DUPLICATE_IF_ADDRESS;
 792               error = clib_error_create
 793                 ("Prefix %U already found on interface %U",
 794                  lm->format_address_and_length, addr_fib, address_length,
 795                  format_vnet_sw_if_index_name, vnm, ia->sw_if_index);
 796             }
 797         }
 798       else
 799         error = ip_interface_address_add (lm, sw_if_index,
 800                                           addr_fib, address_length,
 801                                           &if_address_index);
 802     }
 803
 804   if (error)
 805     goto done;
 806
 807   ip4_sw_interface_enable_disable (sw_if_index, !is_del);
 808   ip4_mfib_interface_enable_disable (sw_if_index, !is_del);
 809
 810   /* intf addr routes are added/deleted on admin up/down */
 811   if (vnet_sw_interface_is_admin_up (vnm, sw_if_index))
 812     {
 813       if (is_del)
 814         ip4_del_interface_routes (sw_if_index,
 815                                   im, ip4_af.fib_index, address,
 816                                   address_length);
 817       else
 818         ip4_add_interface_routes (sw_if_index,
 819                                   im, ip4_af.fib_index,
 820                                   pool_elt_at_index
 821                                   (lm->if_address_pool, if_address_index));
 822     }
 823
 824   ip4_add_del_interface_address_callback_t *cb;
 825   vec_foreach (cb, im->add_del_interface_address_callbacks)
 826     cb->function (im, cb->function_opaque, sw_if_index,
 827                   address, address_length, if_address_index, is_del);
 828
 829 done:
 830   vec_free (addr_fib);
 831   return error;
 832 }
 833
 834 clib_error_t *
 835 ip4_add_del_interface_address (vlib_main_t * vm,
 836                                u32 sw_if_index,
 837                                ip4_address_t * address,
 838                                u32 address_length, u32 is_del)
 839 {
 840   return ip4_add_del_interface_address_internal
 841     (vm, sw_if_index, address, address_length, is_del);
 842 }
 843
 844 void
 845 ip4_directed_broadcast (u32 sw_if_index, u8 enable)
 846 {
 847   ip_interface_address_t *ia;
 848   ip4_main_t *im;
 849
 850   im = &ip4_main;
 851
 852   /*
 853    * when directed broadcast is enabled, the subnet braodcast route will forward
 854    * packets using an adjacency with a broadcast MAC. otherwise it drops
 855    */
 856   /* *INDENT-OFF* */
 857   foreach_ip_interface_address(&im->lookup_main, ia,
 858                                sw_if_index, 0,
 859      ({
 860        if (ia->address_length <= 30)
 861          {
 862            ip4_address_t *ipa;
 863
 864            ipa = ip_interface_address_get_address (&im->lookup_main, ia);
 865
 866            fib_prefix_t pfx = {
 867              .fp_len = 32,
 868              .fp_proto = FIB_PROTOCOL_IP4,
 869              .fp_addr = {
 870                .ip4.as_u32 = (ipa->as_u32 | ~im->fib_masks[ia->address_length]),
 871              },
 872            };
 873
 874            ip4_add_subnet_bcast_route
 875              (fib_table_get_index_for_sw_if_index(FIB_PROTOCOL_IP4,
 876                                                   sw_if_index),
 877               &pfx, sw_if_index);
 878          }
 879      }));
 880   /* *INDENT-ON* */
 881 }
 882 #endif
 883
 884 static clib_error_t *
 885 ip4_sw_interface_admin_up_down (vnet_main_t * vnm, u32 sw_if_index, u32 flags)
 886 {
 887   ip4_main_t *im = &ip4_main;
 888   ip_interface_address_t *ia;
 889   ip4_address_t *a;
 890   u32 is_admin_up, fib_index;
 891
 892   vec_validate_init_empty (im->
 893                            lookup_main.if_address_pool_index_by_sw_if_index,
 894                            sw_if_index, ~0);
 895
 896   is_admin_up = (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) != 0;
 897
 898   fib_index = vec_elt (im->fib_index_by_sw_if_index, sw_if_index);
 899
 900   /* *INDENT-OFF* */
 901   foreach_ip_interface_address (&im->lookup_main, ia, sw_if_index,
 902                                 0 /* honor unnumbered */,
 903   ({
 904     a = ip_interface_address_get_address (&im->lookup_main, ia);
 905     if (is_admin_up)
 906       ip4_add_interface_routes (sw_if_index,
 907                                 im, fib_index,
 908                                 ia);
 909     else
 910       ip4_del_interface_routes (sw_if_index,
 911                                 im, fib_index,
 912                                 a, ia->address_length);
 913   }));
 914   /* *INDENT-ON* */
 915
 916   return 0;
 917 }
 918
 919 VNET_SW_INTERFACE_ADMIN_UP_DOWN_FUNCTION (ip4_sw_interface_admin_up_down);
 920
 921 /* Built-in ip4 unicast rx feature path definition */
 922 /* *INDENT-OFF* */
 923 VNET_FEATURE_ARC_INIT (ip4_unicast, static) =
 924 {
 925   .arc_name = "ip4-unicast",
 926   .start_nodes = VNET_FEATURES ("ip4-input", "ip4-input-no-checksum"),
 927   .last_in_arc = "ip4-lookup",
 928   .arc_index_ptr = &ip4_main.lookup_main.ucast_feature_arc_index,
 929 };
 930
 931 VNET_FEATURE_INIT (ip4_flow_classify, static) =
 932 {
 933   .arc_name = "ip4-unicast",
 934   .node_name = "ip4-flow-classify",
 935   .runs_before = VNET_FEATURES ("ip4-inacl"),
 936 };
 937
 938 VNET_FEATURE_INIT (ip4_inacl, static) =
 939 {
 940   .arc_name = "ip4-unicast",
 941   .node_name = "ip4-inacl",
 942   .runs_before = VNET_FEATURES ("ip4-policer-classify"),
 943 };
 944
 945 VNET_FEATURE_INIT (ip4_source_and_port_range_check_rx, static) =
 946 {
 947   .arc_name = "ip4-unicast",
 948   .node_name = "ip4-source-and-port-range-check-rx",
 949   .runs_before = VNET_FEATURES ("ip4-policer-classify"),
 950 };
 951
 952 VNET_FEATURE_INIT (ip4_policer_classify, static) =
 953 {
 954   .arc_name = "ip4-unicast",
 955   .node_name = "ip4-policer-classify",
 956   .runs_before = VNET_FEATURES ("ipsec4-input-feature"),
 957 };
 958
 959 VNET_FEATURE_INIT (ip4_ipsec, static) =
 960 {
 961   .arc_name = "ip4-unicast",
 962   .node_name = "ipsec4-input-feature",
 963   .runs_before = VNET_FEATURES ("vpath-input-ip4"),
 964 };
 965
 966 VNET_FEATURE_INIT (ip4_vpath, static) =
 967 {
 968   .arc_name = "ip4-unicast",
 969   .node_name = "vpath-input-ip4",
 970   .runs_before = VNET_FEATURES ("ip4-vxlan-bypass"),
 971 };
 972
 973 VNET_FEATURE_INIT (ip4_vxlan_bypass, static) =
 974 {
 975   .arc_name = "ip4-unicast",
 976   .node_name = "ip4-vxlan-bypass",
 977   .runs_before = VNET_FEATURES ("ip4-lookup"),
 978 };
 979
 980 VNET_FEATURE_INIT (ip4_not_enabled, static) =
 981 {
 982   .arc_name = "ip4-unicast",
 983   .node_name = "ip4-not-enabled",
 984   .runs_before = VNET_FEATURES ("ip4-lookup"),
 985 };
 986
 987 VNET_FEATURE_INIT (ip4_lookup, static) =
 988 {
 989   .arc_name = "ip4-unicast",
 990   .node_name = "ip4-lookup",
 991   .runs_before = 0,     /* not before any other features */
 992 };
 993
 994 /* Built-in ip4 multicast rx feature path definition */
 995 VNET_FEATURE_ARC_INIT (ip4_multicast, static) =
 996 {
 997   .arc_name = "ip4-multicast",
 998   .start_nodes = VNET_FEATURES ("ip4-input", "ip4-input-no-checksum"),
 999   .last_in_arc = "ip4-mfib-forward-lookup",
1000   .arc_index_ptr = &ip4_main.lookup_main.mcast_feature_arc_index,
1001 };
1002
1003 VNET_FEATURE_INIT (ip4_vpath_mc, static) =
1004 {
1005   .arc_name = "ip4-multicast",
1006   .node_name = "vpath-input-ip4",
1007   .runs_before = VNET_FEATURES ("ip4-mfib-forward-lookup"),
1008 };
1009
1010 VNET_FEATURE_INIT (ip4_mc_not_enabled, static) =
1011 {
1012   .arc_name = "ip4-multicast",
1013   .node_name = "ip4-not-enabled",
1014   .runs_before = VNET_FEATURES ("ip4-mfib-forward-lookup"),
1015 };
1016
1017 VNET_FEATURE_INIT (ip4_lookup_mc, static) =
1018 {
1019   .arc_name = "ip4-multicast",
1020   .node_name = "ip4-mfib-forward-lookup",
1021   .runs_before = 0,     /* last feature */
1022 };
1023
1024 /* Source and port-range check ip4 tx feature path definition */
1025 VNET_FEATURE_ARC_INIT (ip4_output, static) =
1026 {
1027   .arc_name = "ip4-output",
1028   .start_nodes = VNET_FEATURES ("ip4-rewrite", "ip4-midchain", "ip4-dvr-dpo"),
1029   .last_in_arc = "interface-output",
1030   .arc_index_ptr = &ip4_main.lookup_main.output_feature_arc_index,
1031 };
1032
1033 VNET_FEATURE_INIT (ip4_source_and_port_range_check_tx, static) =
1034 {
1035   .arc_name = "ip4-output",
1036   .node_name = "ip4-source-and-port-range-check-tx",
1037   .runs_before = VNET_FEATURES ("ip4-outacl"),
1038 };
1039
1040 VNET_FEATURE_INIT (ip4_outacl, static) =
1041 {
1042   .arc_name = "ip4-output",
1043   .node_name = "ip4-outacl",
1044   .runs_before = VNET_FEATURES ("ipsec4-output-feature"),
1045 };
1046
1047 VNET_FEATURE_INIT (ip4_ipsec_output, static) =
1048 {
1049   .arc_name = "ip4-output",
1050   .node_name = "ipsec4-output-feature",
1051   .runs_before = VNET_FEATURES ("interface-output"),
1052 };
1053
1054 /* Built-in ip4 tx feature path definition */
1055 VNET_FEATURE_INIT (ip4_interface_output, static) =
1056 {
1057   .arc_name = "ip4-output",
1058   .node_name = "interface-output",
1059   .runs_before = 0,     /* not before any other features */
1060 };
1061 /* *INDENT-ON* */
1062
1063 static clib_error_t *
1064 ip4_sw_interface_add_del (vnet_main_t * vnm, u32 sw_if_index, u32 is_add)
1065 {
1066   ip4_main_t *im = &ip4_main;
1067
1068   vec_validate_init_empty (im->fib_index_by_sw_if_index, sw_if_index, ~0);
1069   vec_validate_init_empty (im->mfib_index_by_sw_if_index, sw_if_index, ~0);
1070
1071   if (is_add)
1072     {
1073       /* Fill in lookup tables with default table (0). */
1074       im->fib_index_by_sw_if_index[sw_if_index] = 0;
1075       im->mfib_index_by_sw_if_index[sw_if_index] = 0;
1076     }
1077   else
1078     {
1079       ip4_main_t *im4 = &ip4_main;
1080       ip_lookup_main_t *lm4 = &im4->lookup_main;
1081       ip_interface_address_t *ia = 0;
1082       ip4_address_t *address;
1083       vlib_main_t *vm = vlib_get_main ();
1084
1085       vnet_sw_interface_update_unnumbered (sw_if_index, ~0, 0);
1086       /* *INDENT-OFF* */
1087       foreach_ip_interface_address (lm4, ia, sw_if_index, 0,
1088       ({
1089         address = ip_interface_address_get_address (lm4, ia);
1090         ip4_add_del_interface_address(vm, sw_if_index, address, ia->address_length, 1);
1091       }));
1092       /* *INDENT-ON* */
1093       ip4_mfib_interface_enable_disable (sw_if_index, 0);
1094
1095       if (0 != im4->fib_index_by_sw_if_index[sw_if_index])
1096         fib_table_bind (FIB_PROTOCOL_IP4, sw_if_index, 0);
1097       if (0 != im4->mfib_index_by_sw_if_index[sw_if_index])
1098         mfib_table_bind (FIB_PROTOCOL_IP4, sw_if_index, 0);
1099
1100       /* Erase the lookup tables just in case */
1101       im4->fib_index_by_sw_if_index[sw_if_index] = ~0;
1102       im4->mfib_index_by_sw_if_index[sw_if_index] = ~0;
1103     }
1104
1105   vnet_feature_enable_disable ("ip4-unicast", "ip4-not-enabled", sw_if_index,
1106                                is_add, 0, 0);
1107
1108   vnet_feature_enable_disable ("ip4-multicast", "ip4-not-enabled",
1109                                sw_if_index, is_add, 0, 0);
1110
1111   return /* no error */ 0;
1112 }
1113
1114 VNET_SW_INTERFACE_ADD_DEL_FUNCTION (ip4_sw_interface_add_del);
1115
1116 /* Global IP4 main. */
1117 #ifndef CLIB_MARCH_VARIANT
1118 ip4_main_t ip4_main;
1119 #endif /* CLIB_MARCH_VARIANT */
1120
1121 static clib_error_t *
1122 ip4_lookup_init (vlib_main_t * vm)
1123 {
1124   ip4_main_t *im = &ip4_main;
1125   clib_error_t *error;
1126   uword i;
1127
1128   if ((error = vlib_call_init_function (vm, vnet_feature_init)))
1129     return error;
1130   if ((error = vlib_call_init_function (vm, ip4_mtrie_module_init)))
1131     return (error);
1132   if ((error = vlib_call_init_function (vm, fib_module_init)))
1133     return error;
1134   if ((error = vlib_call_init_function (vm, mfib_module_init)))
1135     return error;
1136
1137   for (i = 0; i < ARRAY_LEN (im->fib_masks); i++)
1138     {
1139       u32 m;
1140
1141       if (i < 32)
1142         m = pow2_mask (i) << (32 - i);
1143       else
1144         m = ~0;
1145       im->fib_masks[i] = clib_host_to_net_u32 (m);
1146     }
1147
1148   ip_lookup_init (&im->lookup_main, /* is_ip6 */ 0);
1149
1150   /* Create FIB with index 0 and table id of 0. */
1151   fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4, 0,
1152                                      FIB_SOURCE_DEFAULT_ROUTE);
1153   mfib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4, 0,
1154                                       MFIB_SOURCE_DEFAULT_ROUTE);
1155
1156   {
1157     pg_node_t *pn;
1158     pn = pg_get_node (ip4_lookup_node.index);
1159     pn->unformat_edit = unformat_pg_ip4_header;
1160   }
1161
1162   {
1163     ethernet_arp_header_t h;
1164
1165     clib_memset (&h, 0, sizeof (h));
1166
1167 #define _16(f,v) h.f = clib_host_to_net_u16 (v);
1168 #define _8(f,v) h.f = v;
1169     _16 (l2_type, ETHERNET_ARP_HARDWARE_TYPE_ethernet);
1170     _16 (l3_type, ETHERNET_TYPE_IP4);
1171     _8 (n_l2_address_bytes, 6);
1172     _8 (n_l3_address_bytes, 4);
1173     _16 (opcode, ETHERNET_ARP_OPCODE_request);
1174 #undef _16
1175 #undef _8
1176
1177     vlib_packet_template_init (vm, &im->ip4_arp_request_packet_template,
1178                                /* data */ &h,
1179                                sizeof (h),
1180                                /* alloc chunk size */ 8,
1181                                "ip4 arp");
1182   }
1183
1184   return error;
1185 }
1186
1187 VLIB_INIT_FUNCTION (ip4_lookup_init);
1188
1189 typedef struct
1190 {
1191   /* Adjacency taken. */
1192   u32 dpo_index;
1193   u32 flow_hash;
1194   u32 fib_index;
1195
1196   /* Packet data, possibly *after* rewrite. */
1197   u8 packet_data[64 - 1 * sizeof (u32)];
1198 }
1199 ip4_forward_next_trace_t;
1200
1201 #ifndef CLIB_MARCH_VARIANT
1202 u8 *
1203 format_ip4_forward_next_trace (u8 * s, va_list * args)
1204 {
1205   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1206   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1207   ip4_forward_next_trace_t *t = va_arg (*args, ip4_forward_next_trace_t *);
1208   u32 indent = format_get_indent (s);
1209   s = format (s, "%U%U",
1210               format_white_space, indent,
1211               format_ip4_header, t->packet_data, sizeof (t->packet_data));
1212   return s;
1213 }
1214 #endif
1215
1216 static u8 *
1217 format_ip4_lookup_trace (u8 * s, va_list * args)
1218 {
1219   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1220   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1221   ip4_forward_next_trace_t *t = va_arg (*args, ip4_forward_next_trace_t *);
1222   u32 indent = format_get_indent (s);
1223
1224   s = format (s, "fib %d dpo-idx %d flow hash: 0x%08x",
1225               t->fib_index, t->dpo_index, t->flow_hash);
1226   s = format (s, "\n%U%U",
1227               format_white_space, indent,
1228               format_ip4_header, t->packet_data, sizeof (t->packet_data));
1229   return s;
1230 }
1231
1232 static u8 *
1233 format_ip4_rewrite_trace (u8 * s, va_list * args)
1234 {
1235   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
1236   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
1237   ip4_forward_next_trace_t *t = va_arg (*args, ip4_forward_next_trace_t *);
1238   u32 indent = format_get_indent (s);
1239
1240   s = format (s, "tx_sw_if_index %d dpo-idx %d : %U flow hash: 0x%08x",
1241               t->fib_index, t->dpo_index, format_ip_adjacency,
1242               t->dpo_index, FORMAT_IP_ADJACENCY_NONE, t->flow_hash);
1243   s = format (s, "\n%U%U",
1244               format_white_space, indent,
1245               format_ip_adjacency_packet_data,
1246               t->packet_data, sizeof (t->packet_data));
1247   return s;
1248 }
1249
1250 #ifndef CLIB_MARCH_VARIANT
1251 /* Common trace function for all ip4-forward next nodes. */
1252 void
1253 ip4_forward_next_trace (vlib_main_t * vm,
1254                         vlib_node_runtime_t * node,
1255                         vlib_frame_t * frame, vlib_rx_or_tx_t which_adj_index)
1256 {
1257   u32 *from, n_left;
1258   ip4_main_t *im = &ip4_main;
1259
1260   n_left = frame->n_vectors;
1261   from = vlib_frame_vector_args (frame);
1262
1263   while (n_left >= 4)
1264     {
1265       u32 bi0, bi1;
1266       vlib_buffer_t *b0, *b1;
1267       ip4_forward_next_trace_t *t0, *t1;
1268
1269       /* Prefetch next iteration. */
1270       vlib_prefetch_buffer_with_index (vm, from[2], LOAD);
1271       vlib_prefetch_buffer_with_index (vm, from[3], LOAD);
1272
1273       bi0 = from[0];
1274       bi1 = from[1];
1275
1276       b0 = vlib_get_buffer (vm, bi0);
1277       b1 = vlib_get_buffer (vm, bi1);
1278
1279       if (b0->flags & VLIB_BUFFER_IS_TRACED)
1280         {
1281           t0 = vlib_add_trace (vm, node, b0, sizeof (t0[0]));
1282           t0->dpo_index = vnet_buffer (b0)->ip.adj_index[which_adj_index];
1283           t0->flow_hash = vnet_buffer (b0)->ip.flow_hash;
1284           t0->fib_index =
1285             (vnet_buffer (b0)->sw_if_index[VLIB_TX] !=
1286              (u32) ~ 0) ? vnet_buffer (b0)->sw_if_index[VLIB_TX] :
1287             vec_elt (im->fib_index_by_sw_if_index,
1288                      vnet_buffer (b0)->sw_if_index[VLIB_RX]);
1289
1290           clib_memcpy_fast (t0->packet_data,
1291                             vlib_buffer_get_current (b0),
1292                             sizeof (t0->packet_data));
1293         }
1294       if (b1->flags & VLIB_BUFFER_IS_TRACED)
1295         {
1296           t1 = vlib_add_trace (vm, node, b1, sizeof (t1[0]));
1297           t1->dpo_index = vnet_buffer (b1)->ip.adj_index[which_adj_index];
1298           t1->flow_hash = vnet_buffer (b1)->ip.flow_hash;
1299           t1->fib_index =
1300             (vnet_buffer (b1)->sw_if_index[VLIB_TX] !=
1301              (u32) ~ 0) ? vnet_buffer (b1)->sw_if_index[VLIB_TX] :
1302             vec_elt (im->fib_index_by_sw_if_index,
1303                      vnet_buffer (b1)->sw_if_index[VLIB_RX]);
1304           clib_memcpy_fast (t1->packet_data, vlib_buffer_get_current (b1),
1305                             sizeof (t1->packet_data));
1306         }
1307       from += 2;
1308       n_left -= 2;
1309     }
1310
1311   while (n_left >= 1)
1312     {
1313       u32 bi0;
1314       vlib_buffer_t *b0;
1315       ip4_forward_next_trace_t *t0;
1316
1317       bi0 = from[0];
1318
1319       b0 = vlib_get_buffer (vm, bi0);
1320
1321       if (b0->flags & VLIB_BUFFER_IS_TRACED)
1322         {
1323           t0 = vlib_add_trace (vm, node, b0, sizeof (t0[0]));
1324           t0->dpo_index = vnet_buffer (b0)->ip.adj_index[which_adj_index];
1325           t0->flow_hash = vnet_buffer (b0)->ip.flow_hash;
1326           t0->fib_index =
1327             (vnet_buffer (b0)->sw_if_index[VLIB_TX] !=
1328              (u32) ~ 0) ? vnet_buffer (b0)->sw_if_index[VLIB_TX] :
1329             vec_elt (im->fib_index_by_sw_if_index,
1330                      vnet_buffer (b0)->sw_if_index[VLIB_RX]);
1331           clib_memcpy_fast (t0->packet_data, vlib_buffer_get_current (b0),
1332                             sizeof (t0->packet_data));
1333         }
1334       from += 1;
1335       n_left -= 1;
1336     }
1337 }
1338
1339 /* Compute TCP/UDP/ICMP4 checksum in software. */
1340 u16
1341 ip4_tcp_udp_compute_checksum (vlib_main_t * vm, vlib_buffer_t * p0,
1342                               ip4_header_t * ip0)
1343 {
1344   ip_csum_t sum0;
1345   u32 ip_header_length, payload_length_host_byte_order;
1346
1347   /* Initialize checksum with ip header. */
1348   ip_header_length = ip4_header_bytes (ip0);
1349   payload_length_host_byte_order =
1350     clib_net_to_host_u16 (ip0->length) - ip_header_length;
1351   sum0 =
1352     clib_host_to_net_u32 (payload_length_host_byte_order +
1353                           (ip0->protocol << 16));
1354
1355   if (BITS (uword) == 32)
1356     {
1357       sum0 =
1358         ip_csum_with_carry (sum0,
1359                             clib_mem_unaligned (&ip0->src_address, u32));
1360       sum0 =
1361         ip_csum_with_carry (sum0,
1362                             clib_mem_unaligned (&ip0->dst_address, u32));
1363     }
1364   else
1365     sum0 =
1366       ip_csum_with_carry (sum0, clib_mem_unaligned (&ip0->src_address, u64));
1367
1368   return ip_calculate_l4_checksum (vm, p0, sum0,
1369                                    payload_length_host_byte_order, (u8 *) ip0,
1370                                    ip_header_length, NULL);
1371 }
1372
1373 u32
1374 ip4_tcp_udp_validate_checksum (vlib_main_t * vm, vlib_buffer_t * p0)
1375 {
1376   ip4_header_t *ip0 = vlib_buffer_get_current (p0);
1377   udp_header_t *udp0;
1378   u16 sum16;
1379
1380   ASSERT (ip0->protocol == IP_PROTOCOL_TCP
1381           || ip0->protocol == IP_PROTOCOL_UDP);
1382
1383   udp0 = (void *) (ip0 + 1);
1384   if (ip0->protocol == IP_PROTOCOL_UDP && udp0->checksum == 0)
1385     {
1386       p0->flags |= (VNET_BUFFER_F_L4_CHECKSUM_COMPUTED
1387                     | VNET_BUFFER_F_L4_CHECKSUM_CORRECT);
1388       return p0->flags;
1389     }
1390
1391   sum16 = ip4_tcp_udp_compute_checksum (vm, p0, ip0);
1392
1393   p0->flags |= (VNET_BUFFER_F_L4_CHECKSUM_COMPUTED
1394                 | ((sum16 == 0) << VNET_BUFFER_F_LOG2_L4_CHECKSUM_CORRECT));
1395
1396   return p0->flags;
1397 }
1398 #endif
1399
1400 /* *INDENT-OFF* */
1401 VNET_FEATURE_ARC_INIT (ip4_local) = {
1402   .arc_name = "ip4-local",
1403   .start_nodes = VNET_FEATURES ("ip4-local", "ip4-receive"),
1404   .last_in_arc = "ip4-local-end-of-arc",
1405 };
1406 /* *INDENT-ON* */
1407
1408 static inline void
1409 ip4_local_l4_csum_validate (vlib_main_t * vm, vlib_buffer_t * p,
1410                             ip4_header_t * ip, u8 is_udp, u8 * error,
1411                             u8 * good_tcp_udp)
1412 {
1413   u32 flags0;
1414   flags0 = ip4_tcp_udp_validate_checksum (vm, p);
1415   *good_tcp_udp = (flags0 & VNET_BUFFER_F_L4_CHECKSUM_CORRECT) != 0;
1416   if (is_udp)
1417     {
1418       udp_header_t *udp;
1419       u32 ip_len, udp_len;
1420       i32 len_diff;
1421       udp = ip4_next_header (ip);
1422       /* Verify UDP length. */
1423       ip_len = clib_net_to_host_u16 (ip->length);
1424       udp_len = clib_net_to_host_u16 (udp->length);
1425
1426       len_diff = ip_len - udp_len;
1427       *good_tcp_udp &= len_diff >= 0;
1428       *error = len_diff < 0 ? IP4_ERROR_UDP_LENGTH : *error;
1429     }
1430 }
1431
1432 #define ip4_local_csum_is_offloaded(_b)                                       \
1433   ((_b->flags & VNET_BUFFER_F_OFFLOAD) &&                                     \
1434    (vnet_buffer (_b)->oflags &                                                \
1435     (VNET_BUFFER_OFFLOAD_F_TCP_CKSUM | VNET_BUFFER_OFFLOAD_F_UDP_CKSUM)))
1436
1437 #define ip4_local_need_csum_check(is_tcp_udp, _b)                       \
1438     (is_tcp_udp && !(_b->flags & VNET_BUFFER_F_L4_CHECKSUM_COMPUTED     \
1439         || ip4_local_csum_is_offloaded (_b)))
1440
1441 #define ip4_local_csum_is_valid(_b)                                     \
1442     (_b->flags & VNET_BUFFER_F_L4_CHECKSUM_CORRECT                      \
1443         || (ip4_local_csum_is_offloaded (_b))) != 0
1444
1445 static inline void
1446 ip4_local_check_l4_csum (vlib_main_t * vm, vlib_buffer_t * b,
1447                          ip4_header_t * ih, u8 * error)
1448 {
1449   u8 is_udp, is_tcp_udp, good_tcp_udp;
1450
1451   is_udp = ih->protocol == IP_PROTOCOL_UDP;
1452   is_tcp_udp = is_udp || ih->protocol == IP_PROTOCOL_TCP;
1453
1454   if (PREDICT_FALSE (ip4_local_need_csum_check (is_tcp_udp, b)))
1455     ip4_local_l4_csum_validate (vm, b, ih, is_udp, error, &good_tcp_udp);
1456   else
1457     good_tcp_udp = ip4_local_csum_is_valid (b);
1458
1459   ASSERT (IP4_ERROR_TCP_CHECKSUM + 1 == IP4_ERROR_UDP_CHECKSUM);
1460   *error = (is_tcp_udp && !good_tcp_udp
1461             ? IP4_ERROR_TCP_CHECKSUM + is_udp : *error);
1462 }
1463
1464 static inline void
1465 ip4_local_check_l4_csum_x2 (vlib_main_t * vm, vlib_buffer_t ** b,
1466                             ip4_header_t ** ih, u8 * error)
1467 {
1468   u8 is_udp[2], is_tcp_udp[2], good_tcp_udp[2];
1469
1470   is_udp[0] = ih[0]->protocol == IP_PROTOCOL_UDP;
1471   is_udp[1] = ih[1]->protocol == IP_PROTOCOL_UDP;
1472
1473   is_tcp_udp[0] = is_udp[0] || ih[0]->protocol == IP_PROTOCOL_TCP;
1474   is_tcp_udp[1] = is_udp[1] || ih[1]->protocol == IP_PROTOCOL_TCP;
1475
1476   good_tcp_udp[0] = ip4_local_csum_is_valid (b[0]);
1477   good_tcp_udp[1] = ip4_local_csum_is_valid (b[1]);
1478
1479   if (PREDICT_FALSE (ip4_local_need_csum_check (is_tcp_udp[0], b[0])
1480                      || ip4_local_need_csum_check (is_tcp_udp[1], b[1])))
1481     {
1482       if (is_tcp_udp[0])
1483         ip4_local_l4_csum_validate (vm, b[0], ih[0], is_udp[0], &error[0],
1484                                     &good_tcp_udp[0]);
1485       if (is_tcp_udp[1])
1486         ip4_local_l4_csum_validate (vm, b[1], ih[1], is_udp[1], &error[1],
1487                                     &good_tcp_udp[1]);
1488     }
1489
1490   error[0] = (is_tcp_udp[0] && !good_tcp_udp[0] ?
1491               IP4_ERROR_TCP_CHECKSUM + is_udp[0] : error[0]);
1492   error[1] = (is_tcp_udp[1] && !good_tcp_udp[1] ?
1493               IP4_ERROR_TCP_CHECKSUM + is_udp[1] : error[1]);
1494 }
1495
1496 static inline void
1497 ip4_local_set_next_and_error (vlib_node_runtime_t * error_node,
1498                               vlib_buffer_t * b, u16 * next, u8 error,
1499                               u8 head_of_feature_arc)
1500 {
1501   u8 arc_index = vnet_feat_arc_ip4_local.feature_arc_index;
1502   u32 next_index;
1503
1504   *next = error != IP4_ERROR_UNKNOWN_PROTOCOL ? IP_LOCAL_NEXT_DROP : *next;
1505   b->error = error ? error_node->errors[error] : 0;
1506   if (head_of_feature_arc)
1507     {
1508       next_index = *next;
1509       if (PREDICT_TRUE (error == (u8) IP4_ERROR_UNKNOWN_PROTOCOL))
1510         {
1511           vnet_feature_arc_start (arc_index,
1512                                   vnet_buffer (b)->sw_if_index[VLIB_RX],
1513                                   &next_index, b);
1514           *next = next_index;
1515         }
1516     }
1517 }
1518
1519 typedef struct
1520 {
1521   ip4_address_t src;
1522   u32 lbi;
1523   u8 error;
1524   u8 first;
1525 } ip4_local_last_check_t;
1526
1527 static inline void
1528 ip4_local_check_src (vlib_buffer_t *b, ip4_header_t *ip0,
1529                      ip4_local_last_check_t *last_check, u8 *error0,
1530                      int is_receive_dpo)
1531 {
1532   const dpo_id_t *dpo0;
1533   load_balance_t *lb0;
1534   u32 lbi0;
1535
1536   vnet_buffer (b)->ip.fib_index =
1537     vnet_buffer (b)->sw_if_index[VLIB_TX] != ~0 ?
1538     vnet_buffer (b)->sw_if_index[VLIB_TX] : vnet_buffer (b)->ip.fib_index;
1539
1540   if (is_receive_dpo)
1541     {
1542       receive_dpo_t *rd;
1543       rd = receive_dpo_get (vnet_buffer (b)->ip.adj_index[VLIB_TX]);
1544       vnet_buffer (b)->ip.rx_sw_if_index = rd->rd_sw_if_index;
1545     }
1546   else
1547     vnet_buffer (b)->ip.rx_sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
1548
1549   /*
1550    * vnet_buffer()->ip.adj_index[VLIB_RX] will be set to the index of the
1551    *  adjacency for the destination address (the local interface address).
1552    * vnet_buffer()->ip.adj_index[VLIB_TX] will be set to the index of the
1553    *  adjacency for the source address (the remote sender's address)
1554    */
1555   if (PREDICT_TRUE (last_check->src.as_u32 != ip0->src_address.as_u32) ||
1556       last_check->first)
1557     {
1558       lbi0 = ip4_fib_forwarding_lookup (vnet_buffer (b)->ip.fib_index,
1559                                         &ip0->src_address);
1560
1561       vnet_buffer (b)->ip.adj_index[VLIB_RX] =
1562         vnet_buffer (b)->ip.adj_index[VLIB_TX];
1563       vnet_buffer (b)->ip.adj_index[VLIB_TX] = lbi0;
1564
1565       lb0 = load_balance_get (lbi0);
1566       dpo0 = load_balance_get_bucket_i (lb0, 0);
1567
1568       /*
1569        * Must have a route to source otherwise we drop the packet.
1570        * ip4 broadcasts are accepted, e.g. to make dhcp client work
1571        *
1572        * The checks are:
1573        *  - the source is a recieve => it's from us => bogus, do this
1574        *    first since it sets a different error code.
1575        *  - uRPF check for any route to source - accept if passes.
1576        *  - allow packets destined to the broadcast address from unknown sources
1577        */
1578
1579       *error0 = ((*error0 == IP4_ERROR_UNKNOWN_PROTOCOL
1580                   && dpo0->dpoi_type == DPO_RECEIVE) ?
1581                  IP4_ERROR_SPOOFED_LOCAL_PACKETS : *error0);
1582       *error0 = ((*error0 == IP4_ERROR_UNKNOWN_PROTOCOL
1583                   && !fib_urpf_check_size (lb0->lb_urpf)
1584                   && ip0->dst_address.as_u32 != 0xFFFFFFFF) ?
1585                  IP4_ERROR_SRC_LOOKUP_MISS : *error0);
1586
1587       last_check->src.as_u32 = ip0->src_address.as_u32;
1588       last_check->lbi = lbi0;
1589       last_check->error = *error0;
1590       last_check->first = 0;
1591     }
1592   else
1593     {
1594       vnet_buffer (b)->ip.adj_index[VLIB_RX] =
1595         vnet_buffer (b)->ip.adj_index[VLIB_TX];
1596       vnet_buffer (b)->ip.adj_index[VLIB_TX] = last_check->lbi;
1597       *error0 = last_check->error;
1598     }
1599 }
1600
1601 static inline void
1602 ip4_local_check_src_x2 (vlib_buffer_t **b, ip4_header_t **ip,
1603                         ip4_local_last_check_t *last_check, u8 *error,
1604                         int is_receive_dpo)
1605 {
1606   const dpo_id_t *dpo[2];
1607   load_balance_t *lb[2];
1608   u32 not_last_hit;
1609   u32 lbi[2];
1610
1611   not_last_hit = last_check->first;
1612   not_last_hit |= ip[0]->src_address.as_u32 ^ last_check->src.as_u32;
1613   not_last_hit |= ip[1]->src_address.as_u32 ^ last_check->src.as_u32;
1614
1615   vnet_buffer (b[0])->ip.fib_index =
1616     vnet_buffer (b[0])->sw_if_index[VLIB_TX] != ~0 ?
1617     vnet_buffer (b[0])->sw_if_index[VLIB_TX] :
1618     vnet_buffer (b[0])->ip.fib_index;
1619
1620   vnet_buffer (b[1])->ip.fib_index =
1621     vnet_buffer (b[1])->sw_if_index[VLIB_TX] != ~0 ?
1622     vnet_buffer (b[1])->sw_if_index[VLIB_TX] :
1623     vnet_buffer (b[1])->ip.fib_index;
1624
1625   if (is_receive_dpo)
1626     {
1627       const receive_dpo_t *rd0, *rd1;
1628       rd0 = receive_dpo_get (vnet_buffer (b[0])->ip.adj_index[VLIB_TX]);
1629       rd1 = receive_dpo_get (vnet_buffer (b[1])->ip.adj_index[VLIB_TX]);
1630       vnet_buffer (b[0])->ip.rx_sw_if_index = rd0->rd_sw_if_index;
1631       vnet_buffer (b[1])->ip.rx_sw_if_index = rd1->rd_sw_if_index;
1632     }
1633   else
1634     {
1635       vnet_buffer (b[0])->ip.rx_sw_if_index =
1636         vnet_buffer (b[0])->sw_if_index[VLIB_RX];
1637       vnet_buffer (b[1])->ip.rx_sw_if_index =
1638         vnet_buffer (b[1])->sw_if_index[VLIB_RX];
1639     }
1640
1641   /*
1642    * vnet_buffer()->ip.adj_index[VLIB_RX] will be set to the index of the
1643    *  adjacency for the destination address (the local interface address).
1644    * vnet_buffer()->ip.adj_index[VLIB_TX] will be set to the index of the
1645    *  adjacency for the source address (the remote sender's address)
1646    */
1647   if (PREDICT_TRUE (not_last_hit))
1648     {
1649       ip4_fib_forwarding_lookup_x2 (
1650         vnet_buffer (b[0])->ip.fib_index, vnet_buffer (b[1])->ip.fib_index,
1651         &ip[0]->src_address, &ip[1]->src_address, &lbi[0], &lbi[1]);
1652
1653       vnet_buffer (b[0])->ip.adj_index[VLIB_RX] =
1654         vnet_buffer (b[0])->ip.adj_index[VLIB_TX];
1655       vnet_buffer (b[0])->ip.adj_index[VLIB_TX] = lbi[0];
1656
1657       vnet_buffer (b[1])->ip.adj_index[VLIB_RX] =
1658         vnet_buffer (b[1])->ip.adj_index[VLIB_TX];
1659       vnet_buffer (b[1])->ip.adj_index[VLIB_TX] = lbi[1];
1660
1661       lb[0] = load_balance_get (lbi[0]);
1662       lb[1] = load_balance_get (lbi[1]);
1663
1664       dpo[0] = load_balance_get_bucket_i (lb[0], 0);
1665       dpo[1] = load_balance_get_bucket_i (lb[1], 0);
1666
1667       error[0] = ((error[0] == IP4_ERROR_UNKNOWN_PROTOCOL &&
1668                    dpo[0]->dpoi_type == DPO_RECEIVE) ?
1669                   IP4_ERROR_SPOOFED_LOCAL_PACKETS : error[0]);
1670       error[0] = ((error[0] == IP4_ERROR_UNKNOWN_PROTOCOL &&
1671                    !fib_urpf_check_size (lb[0]->lb_urpf) &&
1672                    ip[0]->dst_address.as_u32 != 0xFFFFFFFF)
1673                   ? IP4_ERROR_SRC_LOOKUP_MISS : error[0]);
1674
1675       error[1] = ((error[1] == IP4_ERROR_UNKNOWN_PROTOCOL &&
1676                    dpo[1]->dpoi_type == DPO_RECEIVE) ?
1677                   IP4_ERROR_SPOOFED_LOCAL_PACKETS : error[1]);
1678       error[1] = ((error[1] == IP4_ERROR_UNKNOWN_PROTOCOL &&
1679                    !fib_urpf_check_size (lb[1]->lb_urpf) &&
1680                    ip[1]->dst_address.as_u32 != 0xFFFFFFFF)
1681                   ? IP4_ERROR_SRC_LOOKUP_MISS : error[1]);
1682
1683       last_check->src.as_u32 = ip[1]->src_address.as_u32;
1684       last_check->lbi = lbi[1];
1685       last_check->error = error[1];
1686       last_check->first = 0;
1687     }
1688   else
1689     {
1690       vnet_buffer (b[0])->ip.adj_index[VLIB_RX] =
1691         vnet_buffer (b[0])->ip.adj_index[VLIB_TX];
1692       vnet_buffer (b[0])->ip.adj_index[VLIB_TX] = last_check->lbi;
1693
1694       vnet_buffer (b[1])->ip.adj_index[VLIB_RX] =
1695         vnet_buffer (b[1])->ip.adj_index[VLIB_TX];
1696       vnet_buffer (b[1])->ip.adj_index[VLIB_TX] = last_check->lbi;
1697
1698       error[0] = last_check->error;
1699       error[1] = last_check->error;
1700     }
1701 }
1702
1703 enum ip_local_packet_type_e
1704 {
1705   IP_LOCAL_PACKET_TYPE_L4,
1706   IP_LOCAL_PACKET_TYPE_NAT,
1707   IP_LOCAL_PACKET_TYPE_FRAG,
1708 };
1709
1710 /**
1711  * Determine packet type and next node.
1712  *
1713  * The expectation is that all packets that are not L4 will skip
1714  * checksums and source checks.
1715  */
1716 always_inline u8
1717 ip4_local_classify (vlib_buffer_t * b, ip4_header_t * ip, u16 * next)
1718 {
1719   ip_lookup_main_t *lm = &ip4_main.lookup_main;
1720
1721   if (PREDICT_FALSE (ip4_is_fragment (ip)))
1722     {
1723       *next = IP_LOCAL_NEXT_REASSEMBLY;
1724       return IP_LOCAL_PACKET_TYPE_FRAG;
1725     }
1726   if (PREDICT_FALSE (b->flags & VNET_BUFFER_F_IS_NATED))
1727     {
1728       *next = lm->local_next_by_ip_protocol[ip->protocol];
1729       return IP_LOCAL_PACKET_TYPE_NAT;
1730     }
1731
1732   *next = lm->local_next_by_ip_protocol[ip->protocol];
1733   return IP_LOCAL_PACKET_TYPE_L4;
1734 }
1735
1736 static inline uword
1737 ip4_local_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
1738                   vlib_frame_t *frame, int head_of_feature_arc,
1739                   int is_receive_dpo)
1740 {
1741   u32 *from, n_left_from;
1742   vlib_node_runtime_t *error_node =
1743     vlib_node_get_runtime (vm, ip4_local_node.index);
1744   u16 nexts[VLIB_FRAME_SIZE], *next;
1745   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
1746   ip4_header_t *ip[2];
1747   u8 error[2], pt[2];
1748
1749   ip4_local_last_check_t last_check = {
1750     /*
1751      * 0.0.0.0 can appear as the source address of an IP packet,
1752      * as can any other address, hence the need to use the 'first'
1753      * member to make sure the .lbi is initialised for the first
1754      * packet.
1755      */
1756     .src = {.as_u32 = 0},
1757     .lbi = ~0,
1758     .error = IP4_ERROR_UNKNOWN_PROTOCOL,
1759     .first = 1,
1760   };
1761
1762   from = vlib_frame_vector_args (frame);
1763   n_left_from = frame->n_vectors;
1764
1765   if (node->flags & VLIB_NODE_FLAG_TRACE)
1766     ip4_forward_next_trace (vm, node, frame, VLIB_TX);
1767
1768   vlib_get_buffers (vm, from, bufs, n_left_from);
1769   b = bufs;
1770   next = nexts;
1771
1772   while (n_left_from >= 6)
1773     {
1774       u8 not_batch = 0;
1775
1776       /* Prefetch next iteration. */
1777       {
1778         vlib_prefetch_buffer_header (b[4], LOAD);
1779         vlib_prefetch_buffer_header (b[5], LOAD);
1780
1781         clib_prefetch_load (b[4]->data);
1782         clib_prefetch_load (b[5]->data);
1783       }
1784
1785       error[0] = error[1] = IP4_ERROR_UNKNOWN_PROTOCOL;
1786
1787       ip[0] = vlib_buffer_get_current (b[0]);
1788       ip[1] = vlib_buffer_get_current (b[1]);
1789
1790       vnet_buffer (b[0])->l3_hdr_offset = b[0]->current_data;
1791       vnet_buffer (b[1])->l3_hdr_offset = b[1]->current_data;
1792
1793       pt[0] = ip4_local_classify (b[0], ip[0], &next[0]);
1794       pt[1] = ip4_local_classify (b[1], ip[1], &next[1]);
1795
1796       not_batch = pt[0] ^ pt[1];
1797
1798       if (head_of_feature_arc == 0 || (pt[0] && not_batch == 0))
1799         goto skip_checks;
1800
1801       if (PREDICT_TRUE (not_batch == 0))
1802         {
1803           ip4_local_check_l4_csum_x2 (vm, b, ip, error);
1804           ip4_local_check_src_x2 (b, ip, &last_check, error, is_receive_dpo);
1805         }
1806       else
1807         {
1808           if (!pt[0])
1809             {
1810               ip4_local_check_l4_csum (vm, b[0], ip[0], &error[0]);
1811               ip4_local_check_src (b[0], ip[0], &last_check, &error[0],
1812                                    is_receive_dpo);
1813             }
1814           if (!pt[1])
1815             {
1816               ip4_local_check_l4_csum (vm, b[1], ip[1], &error[1]);
1817               ip4_local_check_src (b[1], ip[1], &last_check, &error[1],
1818                                    is_receive_dpo);
1819             }
1820         }
1821
1822     skip_checks:
1823
1824       ip4_local_set_next_and_error (error_node, b[0], &next[0], error[0],
1825                                     head_of_feature_arc);
1826       ip4_local_set_next_and_error (error_node, b[1], &next[1], error[1],
1827                                     head_of_feature_arc);
1828
1829       b += 2;
1830       next += 2;
1831       n_left_from -= 2;
1832     }
1833
1834   while (n_left_from > 0)
1835     {
1836       error[0] = IP4_ERROR_UNKNOWN_PROTOCOL;
1837
1838       ip[0] = vlib_buffer_get_current (b[0]);
1839       vnet_buffer (b[0])->l3_hdr_offset = b[0]->current_data;
1840       pt[0] = ip4_local_classify (b[0], ip[0], &next[0]);
1841
1842       if (head_of_feature_arc == 0 || pt[0])
1843         goto skip_check;
1844
1845       ip4_local_check_l4_csum (vm, b[0], ip[0], &error[0]);
1846       ip4_local_check_src (b[0], ip[0], &last_check, &error[0],
1847                            is_receive_dpo);
1848
1849     skip_check:
1850
1851       ip4_local_set_next_and_error (error_node, b[0], &next[0], error[0],
1852                                     head_of_feature_arc);
1853
1854       b += 1;
1855       next += 1;
1856       n_left_from -= 1;
1857     }
1858
1859   vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
1860   return frame->n_vectors;
1861 }
1862
1863 VLIB_NODE_FN (ip4_local_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
1864                                vlib_frame_t * frame)
1865 {
1866   return ip4_local_inline (vm, node, frame, 1 /* head of feature arc */,
1867                            0 /* is_receive_dpo */);
1868 }
1869
1870 VLIB_REGISTER_NODE (ip4_local_node) =
1871 {
1872   .name = "ip4-local",
1873   .vector_size = sizeof (u32),
1874   .format_trace = format_ip4_forward_next_trace,
1875   .n_errors = IP4_N_ERROR,
1876   .error_strings = ip4_error_strings,
1877   .n_next_nodes = IP_LOCAL_N_NEXT,
1878   .next_nodes =
1879   {
1880     [IP_LOCAL_NEXT_DROP] = "ip4-drop",
1881     [IP_LOCAL_NEXT_PUNT] = "ip4-punt",
1882     [IP_LOCAL_NEXT_UDP_LOOKUP] = "ip4-udp-lookup",
1883     [IP_LOCAL_NEXT_ICMP] = "ip4-icmp-input",
1884     [IP_LOCAL_NEXT_REASSEMBLY] = "ip4-local-full-reassembly",
1885   },
1886 };
1887
1888 VLIB_NODE_FN (ip4_receive_local_node)
1889 (vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
1890 {
1891   return ip4_local_inline (vm, node, frame, 1 /* head of feature arc */,
1892                            1 /* is_receive_dpo */);
1893 }
1894
1895 VLIB_REGISTER_NODE (ip4_receive_local_node) = {
1896   .name = "ip4-receive",
1897   .vector_size = sizeof (u32),
1898   .format_trace = format_ip4_forward_next_trace,
1899   .sibling_of = "ip4-local"
1900 };
1901
1902 VLIB_NODE_FN (ip4_local_end_of_arc_node) (vlib_main_t * vm,
1903                                           vlib_node_runtime_t * node,
1904                                           vlib_frame_t * frame)
1905 {
1906   return ip4_local_inline (vm, node, frame, 0 /* head of feature arc */,
1907                            0 /* is_receive_dpo */);
1908 }
1909
1910 VLIB_REGISTER_NODE (ip4_local_end_of_arc_node) = {
1911   .name = "ip4-local-end-of-arc",
1912   .vector_size = sizeof (u32),
1913
1914   .format_trace = format_ip4_forward_next_trace,
1915   .sibling_of = "ip4-local",
1916 };
1917
1918 VNET_FEATURE_INIT (ip4_local_end_of_arc, static) = {
1919   .arc_name = "ip4-local",
1920   .node_name = "ip4-local-end-of-arc",
1921   .runs_before = 0, /* not before any other features */
1922 };
1923
1924 #ifndef CLIB_MARCH_VARIANT
1925 void
1926 ip4_register_protocol (u32 protocol, u32 node_index)
1927 {
1928   vlib_main_t *vm = vlib_get_main ();
1929   ip4_main_t *im = &ip4_main;
1930   ip_lookup_main_t *lm = &im->lookup_main;
1931
1932   ASSERT (protocol < ARRAY_LEN (lm->local_next_by_ip_protocol));
1933   lm->local_next_by_ip_protocol[protocol] =
1934     vlib_node_add_next (vm, ip4_local_node.index, node_index);
1935 }
1936
1937 void
1938 ip4_unregister_protocol (u32 protocol)
1939 {
1940   ip4_main_t *im = &ip4_main;
1941   ip_lookup_main_t *lm = &im->lookup_main;
1942
1943   ASSERT (protocol < ARRAY_LEN (lm->local_next_by_ip_protocol));
1944   lm->local_next_by_ip_protocol[protocol] = IP_LOCAL_NEXT_PUNT;
1945 }
1946 #endif
1947
1948 static clib_error_t *
1949 show_ip_local_command_fn (vlib_main_t * vm,
1950                           unformat_input_t * input, vlib_cli_command_t * cmd)
1951 {
1952   ip4_main_t *im = &ip4_main;
1953   ip_lookup_main_t *lm = &im->lookup_main;
1954   int i;
1955
1956   vlib_cli_output (vm, "Protocols handled by ip4_local");
1957   for (i = 0; i < ARRAY_LEN (lm->local_next_by_ip_protocol); i++)
1958     {
1959       if (lm->local_next_by_ip_protocol[i] != IP_LOCAL_NEXT_PUNT)
1960         {
1961           u32 node_index = vlib_get_node (vm,
1962                                           ip4_local_node.index)->
1963             next_nodes[lm->local_next_by_ip_protocol[i]];
1964           vlib_cli_output (vm, "%U: %U", format_ip_protocol, i,
1965                            format_vlib_node_name, vm, node_index);
1966         }
1967     }
1968   return 0;
1969 }
1970
1971
1972
1973 /*?
1974  * Display the set of protocols handled by the local IPv4 stack.
1975  *
1976  * @cliexpar
1977  * Example of how to display local protocol table:
1978  * @cliexstart{show ip local}
1979  * Protocols handled by ip4_local
1980  * 1
1981  * 17
1982  * 47
1983  * @cliexend
1984 ?*/
1985 /* *INDENT-OFF* */
1986 VLIB_CLI_COMMAND (show_ip_local, static) =
1987 {
1988   .path = "show ip local",
1989   .function = show_ip_local_command_fn,
1990   .short_help = "show ip local",
1991 };
1992 /* *INDENT-ON* */
1993
1994 typedef enum
1995 {
1996   IP4_REWRITE_NEXT_DROP,
1997   IP4_REWRITE_NEXT_ICMP_ERROR,
1998   IP4_REWRITE_NEXT_FRAGMENT,
1999   IP4_REWRITE_N_NEXT            /* Last */
2000 } ip4_rewrite_next_t;
2001
2002 /**
2003  * This bits of an IPv4 address to mask to construct a multicast
2004  * MAC address
2005  */
2006 #if CLIB_ARCH_IS_BIG_ENDIAN
2007 #define IP4_MCAST_ADDR_MASK 0x007fffff
2008 #else
2009 #define IP4_MCAST_ADDR_MASK 0xffff7f00
2010 #endif
2011
2012 always_inline void
2013 ip4_mtu_check (vlib_buffer_t * b, u16 packet_len,
2014                u16 adj_packet_bytes, bool df, u16 * next,
2015                u8 is_midchain, u32 * error)
2016 {
2017   if (packet_len > adj_packet_bytes)
2018     {
2019       *error = IP4_ERROR_MTU_EXCEEDED;
2020       if (df)
2021         {
2022           icmp4_error_set_vnet_buffer
2023             (b, ICMP4_destination_unreachable,
2024              ICMP4_destination_unreachable_fragmentation_needed_and_dont_fragment_set,
2025              adj_packet_bytes);
2026           *next = IP4_REWRITE_NEXT_ICMP_ERROR;
2027         }
2028       else
2029         {
2030           /* IP fragmentation */
2031           ip_frag_set_vnet_buffer (b, adj_packet_bytes,
2032                                    (is_midchain ?
2033                                     IP_FRAG_NEXT_IP_REWRITE_MIDCHAIN :
2034                                     IP_FRAG_NEXT_IP_REWRITE), 0);
2035           *next = IP4_REWRITE_NEXT_FRAGMENT;
2036         }
2037     }
2038 }
2039
2040 /* increment TTL & update checksum.
2041    Works either endian, so no need for byte swap. */
2042 static_always_inline void
2043 ip4_ttl_inc (vlib_buffer_t * b, ip4_header_t * ip)
2044 {
2045   i32 ttl;
2046   u32 checksum;
2047   if (PREDICT_FALSE (b->flags & VNET_BUFFER_F_LOCALLY_ORIGINATED))
2048     return;
2049
2050   ttl = ip->ttl;
2051
2052   checksum = ip->checksum - clib_host_to_net_u16 (0x0100);
2053   checksum += checksum >= 0xffff;
2054
2055   ip->checksum = checksum;
2056   ttl += 1;
2057   ip->ttl = ttl;
2058
2059   ASSERT (ip4_header_checksum_is_valid (ip));
2060 }
2061
2062 /* Decrement TTL & update checksum.
2063    Works either endian, so no need for byte swap. */
2064 static_always_inline void
2065 ip4_ttl_and_checksum_check (vlib_buffer_t * b, ip4_header_t * ip, u16 * next,
2066                             u32 * error)
2067 {
2068   i32 ttl;
2069   u32 checksum;
2070   if (PREDICT_FALSE (b->flags & VNET_BUFFER_F_LOCALLY_ORIGINATED))
2071     return;
2072
2073   ttl = ip->ttl;
2074
2075   /* Input node should have reject packets with ttl 0. */
2076   ASSERT (ip->ttl > 0);
2077
2078   checksum = ip->checksum + clib_host_to_net_u16 (0x0100);
2079   checksum += checksum >= 0xffff;
2080
2081   ip->checksum = checksum;
2082   ttl -= 1;
2083   ip->ttl = ttl;
2084
2085   /*
2086    * If the ttl drops below 1 when forwarding, generate
2087    * an ICMP response.
2088    */
2089   if (PREDICT_FALSE (ttl <= 0))
2090     {
2091       *error = IP4_ERROR_TIME_EXPIRED;
2092       vnet_buffer (b)->sw_if_index[VLIB_TX] = (u32) ~ 0;
2093       icmp4_error_set_vnet_buffer (b, ICMP4_time_exceeded,
2094                                    ICMP4_time_exceeded_ttl_exceeded_in_transit,
2095                                    0);
2096       *next = IP4_REWRITE_NEXT_ICMP_ERROR;
2097     }
2098
2099   /* Verify checksum. */
2100   ASSERT (ip4_header_checksum_is_valid (ip) ||
2101           (vnet_buffer (b)->oflags & VNET_BUFFER_OFFLOAD_F_IP_CKSUM) ||
2102           (vnet_buffer (b)->oflags & VNET_BUFFER_OFFLOAD_F_OUTER_IP_CKSUM));
2103 }
2104
2105 always_inline uword
2106 ip4_rewrite_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
2107                     vlib_frame_t *frame, int do_counters, int is_midchain,
2108                     int is_mcast)
2109 {
2110   ip_lookup_main_t *lm = &ip4_main.lookup_main;
2111   u32 *from = vlib_frame_vector_args (frame);
2112   vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
2113   u16 nexts[VLIB_FRAME_SIZE], *next;
2114   u32 n_left_from;
2115   vlib_node_runtime_t *error_node =
2116     vlib_node_get_runtime (vm, ip4_input_node.index);
2117
2118   n_left_from = frame->n_vectors;
2119   u32 thread_index = vm->thread_index;
2120
2121   vlib_get_buffers (vm, from, bufs, n_left_from);
2122   clib_memset_u16 (nexts, IP4_REWRITE_NEXT_DROP, n_left_from);
2123
2124 #if (CLIB_N_PREFETCHES >= 8)
2125   if (n_left_from >= 6)
2126     {
2127       int i;
2128       for (i = 2; i < 6; i++)
2129         vlib_prefetch_buffer_header (bufs[i], LOAD);
2130     }
2131
2132   next = nexts;
2133   b = bufs;
2134   while (n_left_from >= 8)
2135     {
2136       const ip_adjacency_t *adj0, *adj1;
2137       ip4_header_t *ip0, *ip1;
2138       u32 rw_len0, error0, adj_index0;
2139       u32 rw_len1, error1, adj_index1;
2140       u32 tx_sw_if_index0, tx_sw_if_index1;
2141       u8 *p;
2142
2143       if (is_midchain)
2144         {
2145           vlib_prefetch_buffer_header (b[6], LOAD);
2146           vlib_prefetch_buffer_header (b[7], LOAD);
2147         }
2148
2149       adj_index0 = vnet_buffer (b[0])->ip.adj_index[VLIB_TX];
2150       adj_index1 = vnet_buffer (b[1])->ip.adj_index[VLIB_TX];
2151
2152       /*
2153        * pre-fetch the per-adjacency counters
2154        */
2155       if (do_counters)
2156         {
2157           vlib_prefetch_combined_counter (&adjacency_counters,
2158                                           thread_index, adj_index0);
2159           vlib_prefetch_combined_counter (&adjacency_counters,
2160                                           thread_index, adj_index1);
2161         }
2162
2163       ip0 = vlib_buffer_get_current (b[0]);
2164       ip1 = vlib_buffer_get_current (b[1]);
2165
2166       error0 = error1 = IP4_ERROR_NONE;
2167
2168       ip4_ttl_and_checksum_check (b[0], ip0, next + 0, &error0);
2169       ip4_ttl_and_checksum_check (b[1], ip1, next + 1, &error1);
2170
2171       /* Rewrite packet header and updates lengths. */
2172       adj0 = adj_get (adj_index0);
2173       adj1 = adj_get (adj_index1);
2174
2175       /* Worth pipelining. No guarantee that adj0,1 are hot... */
2176       rw_len0 = adj0[0].rewrite_header.data_bytes;
2177       rw_len1 = adj1[0].rewrite_header.data_bytes;
2178       vnet_buffer (b[0])->ip.save_rewrite_length = rw_len0;
2179       vnet_buffer (b[1])->ip.save_rewrite_length = rw_len1;
2180
2181       p = vlib_buffer_get_current (b[2]);
2182       clib_prefetch_store (p - CLIB_CACHE_LINE_BYTES);
2183       clib_prefetch_load (p);
2184
2185       p = vlib_buffer_get_current (b[3]);
2186       clib_prefetch_store (p - CLIB_CACHE_LINE_BYTES);
2187       clib_prefetch_load (p);
2188
2189       /* Check MTU of outgoing interface. */
2190       u16 ip0_len = clib_net_to_host_u16 (ip0->length);
2191       u16 ip1_len = clib_net_to_host_u16 (ip1->length);
2192
2193       if (b[0]->flags & VNET_BUFFER_F_GSO)
2194         ip0_len = gso_mtu_sz (b[0]);
2195       if (b[1]->flags & VNET_BUFFER_F_GSO)
2196         ip1_len = gso_mtu_sz (b[1]);
2197
2198       ip4_mtu_check (b[0], ip0_len,
2199                      adj0[0].rewrite_header.max_l3_packet_bytes,
2200                      ip0->flags_and_fragment_offset &
2201                      clib_host_to_net_u16 (IP4_HEADER_FLAG_DONT_FRAGMENT),
2202                      next + 0, is_midchain, &error0);
2203       ip4_mtu_check (b[1], ip1_len,
2204                      adj1[0].rewrite_header.max_l3_packet_bytes,
2205                      ip1->flags_and_fragment_offset &
2206                      clib_host_to_net_u16 (IP4_HEADER_FLAG_DONT_FRAGMENT),
2207                      next + 1, is_midchain, &error1);
2208
2209       if (is_mcast)
2210         {
2211           error0 = ((adj0[0].rewrite_header.sw_if_index ==
2212                      vnet_buffer (b[0])->sw_if_index[VLIB_RX]) ?
2213                     IP4_ERROR_SAME_INTERFACE : error0);
2214           error1 = ((adj1[0].rewrite_header.sw_if_index ==
2215                      vnet_buffer (b[1])->sw_if_index[VLIB_RX]) ?
2216                     IP4_ERROR_SAME_INTERFACE : error1);
2217         }
2218
2219       /* Don't adjust the buffer for ttl issue; icmp-error node wants
2220        * to see the IP header */
2221       if (PREDICT_TRUE (error0 == IP4_ERROR_NONE))
2222         {
2223           u32 next_index = adj0[0].rewrite_header.next_index;
2224           vlib_buffer_advance (b[0], -(word) rw_len0);
2225
2226           tx_sw_if_index0 = adj0[0].rewrite_header.sw_if_index;
2227           vnet_buffer (b[0])->sw_if_index[VLIB_TX] = tx_sw_if_index0;
2228
2229           if (PREDICT_FALSE
2230               (adj0[0].rewrite_header.flags & VNET_REWRITE_HAS_FEATURES))
2231             vnet_feature_arc_start_w_cfg_index (lm->output_feature_arc_index,
2232                                                 tx_sw_if_index0,
2233                                                 &next_index, b[0],
2234                                                 adj0->ia_cfg_index);
2235
2236           next[0] = next_index;
2237           if (is_midchain)
2238             vnet_calc_checksums_inline (vm, b[0], 1 /* is_ip4 */ ,
2239                                         0 /* is_ip6 */ );
2240         }
2241       else
2242         {
2243           b[0]->error = error_node->errors[error0];
2244           if (error0 == IP4_ERROR_MTU_EXCEEDED)
2245             ip4_ttl_inc (b[0], ip0);
2246         }
2247       if (PREDICT_TRUE (error1 == IP4_ERROR_NONE))
2248         {
2249           u32 next_index = adj1[0].rewrite_header.next_index;
2250           vlib_buffer_advance (b[1], -(word) rw_len1);
2251
2252           tx_sw_if_index1 = adj1[0].rewrite_header.sw_if_index;
2253           vnet_buffer (b[1])->sw_if_index[VLIB_TX] = tx_sw_if_index1;
2254
2255           if (PREDICT_FALSE
2256               (adj1[0].rewrite_header.flags & VNET_REWRITE_HAS_FEATURES))
2257             vnet_feature_arc_start_w_cfg_index (lm->output_feature_arc_index,
2258                                                 tx_sw_if_index1,
2259                                                 &next_index, b[1],
2260                                                 adj1->ia_cfg_index);
2261           next[1] = next_index;
2262           if (is_midchain)
2263             vnet_calc_checksums_inline (vm, b[1], 1 /* is_ip4 */ ,
2264                                         0 /* is_ip6 */ );
2265         }
2266       else
2267         {
2268           b[1]->error = error_node->errors[error1];
2269           if (error1 == IP4_ERROR_MTU_EXCEEDED)
2270             ip4_ttl_inc (b[1], ip1);
2271         }
2272
2273       if (is_midchain)
2274         /* Guess we are only writing on ipv4 header. */
2275         vnet_rewrite_two_headers (adj0[0], adj1[0],
2276                                   ip0, ip1, sizeof (ip4_header_t));
2277       else
2278         /* Guess we are only writing on simple Ethernet header. */
2279         vnet_rewrite_two_headers (adj0[0], adj1[0],
2280                                   ip0, ip1, sizeof (ethernet_header_t));
2281
2282       if (do_counters)
2283         {
2284           if (error0 == IP4_ERROR_NONE)
2285             vlib_increment_combined_counter
2286               (&adjacency_counters,
2287                thread_index,
2288                adj_index0, 1,
2289                vlib_buffer_length_in_chain (vm, b[0]) + rw_len0);
2290
2291           if (error1 == IP4_ERROR_NONE)
2292             vlib_increment_combined_counter
2293               (&adjacency_counters,
2294                thread_index,
2295                adj_index1, 1,
2296                vlib_buffer_length_in_chain (vm, b[1]) + rw_len1);
2297         }
2298
2299       if (is_midchain)
2300         {
2301           if (error0 == IP4_ERROR_NONE)
2302             adj_midchain_fixup (vm, adj0, b[0], VNET_LINK_IP4);
2303           if (error1 == IP4_ERROR_NONE)
2304             adj_midchain_fixup (vm, adj1, b[1], VNET_LINK_IP4);
2305         }
2306
2307       if (is_mcast)
2308         {
2309           /* copy bytes from the IP address into the MAC rewrite */
2310           if (error0 == IP4_ERROR_NONE)
2311             vnet_ip_mcast_fixup_header (IP4_MCAST_ADDR_MASK,
2312                                         adj0->rewrite_header.dst_mcast_offset,
2313                                         &ip0->dst_address.as_u32, (u8 *) ip0);
2314           if (error1 == IP4_ERROR_NONE)
2315             vnet_ip_mcast_fixup_header (IP4_MCAST_ADDR_MASK,
2316                                         adj1->rewrite_header.dst_mcast_offset,
2317                                         &ip1->dst_address.as_u32, (u8 *) ip1);
2318         }
2319
2320       next += 2;
2321       b += 2;
2322       n_left_from -= 2;
2323     }
2324 #elif (CLIB_N_PREFETCHES >= 4)
2325   next = nexts;
2326   b = bufs;
2327   while (n_left_from >= 1)
2328     {
2329       ip_adjacency_t *adj0;
2330       ip4_header_t *ip0;
2331       u32 rw_len0, error0, adj_index0;
2332       u32 tx_sw_if_index0;
2333       u8 *p;
2334
2335       /* Prefetch next iteration */
2336       if (PREDICT_TRUE (n_left_from >= 4))
2337         {
2338           ip_adjacency_t *adj2;
2339           u32 adj_index2;
2340
2341           vlib_prefetch_buffer_header (b[3], LOAD);
2342           vlib_prefetch_buffer_data (b[2], LOAD);
2343
2344           /* Prefetch adj->rewrite_header */
2345           adj_index2 = vnet_buffer (b[2])->ip.adj_index[VLIB_TX];
2346           adj2 = adj_get (adj_index2);
2347           p = (u8 *) adj2;
2348           CLIB_PREFETCH (p + CLIB_CACHE_LINE_BYTES, CLIB_CACHE_LINE_BYTES,
2349                          LOAD);
2350         }
2351
2352       adj_index0 = vnet_buffer (b[0])->ip.adj_index[VLIB_TX];
2353
2354       /*
2355        * Prefetch the per-adjacency counters
2356        */
2357       if (do_counters)
2358         {
2359           vlib_prefetch_combined_counter (&adjacency_counters,
2360                                           thread_index, adj_index0);
2361         }
2362
2363       ip0 = vlib_buffer_get_current (b[0]);
2364
2365       error0 = IP4_ERROR_NONE;
2366
2367       ip4_ttl_and_checksum_check (b[0], ip0, next + 0, &error0);
2368
2369       /* Rewrite packet header and updates lengths. */
2370       adj0 = adj_get (adj_index0);
2371
2372       /* Rewrite header was prefetched. */
2373       rw_len0 = adj0[0].rewrite_header.data_bytes;
2374       vnet_buffer (b[0])->ip.save_rewrite_length = rw_len0;
2375
2376       /* Check MTU of outgoing interface. */
2377       u16 ip0_len = clib_net_to_host_u16 (ip0->length);
2378
2379       if (b[0]->flags & VNET_BUFFER_F_GSO)
2380         ip0_len = gso_mtu_sz (b[0]);
2381
2382       ip4_mtu_check (b[0], ip0_len,
2383                      adj0[0].rewrite_header.max_l3_packet_bytes,
2384                      ip0->flags_and_fragment_offset &
2385                      clib_host_to_net_u16 (IP4_HEADER_FLAG_DONT_FRAGMENT),
2386                      next + 0, is_midchain, &error0);
2387
2388       if (is_mcast)
2389         {
2390           error0 = ((adj0[0].rewrite_header.sw_if_index ==
2391                      vnet_buffer (b[0])->sw_if_index[VLIB_RX]) ?
2392                     IP4_ERROR_SAME_INTERFACE : error0);
2393         }
2394
2395       /* Don't adjust the buffer for ttl issue; icmp-error node wants
2396        * to see the IP header */
2397       if (PREDICT_TRUE (error0 == IP4_ERROR_NONE))
2398         {
2399           u32 next_index = adj0[0].rewrite_header.next_index;
2400           vlib_buffer_advance (b[0], -(word) rw_len0);
2401           tx_sw_if_index0 = adj0[0].rewrite_header.sw_if_index;
2402           vnet_buffer (b[0])->sw_if_index[VLIB_TX] = tx_sw_if_index0;
2403
2404           if (PREDICT_FALSE
2405               (adj0[0].rewrite_header.flags & VNET_REWRITE_HAS_FEATURES))
2406             vnet_feature_arc_start_w_cfg_index (lm->output_feature_arc_index,
2407                                                 tx_sw_if_index0,
2408                                                 &next_index, b[0],
2409                                                 adj0->ia_cfg_index);
2410           next[0] = next_index;
2411
2412           if (is_midchain)
2413             {
2414               vnet_calc_checksums_inline (vm, b[0], 1 /* is_ip4 */ ,
2415                                           0 /* is_ip6 */ );
2416
2417               /* Guess we are only writing on ipv4 header. */
2418               vnet_rewrite_one_header (adj0[0], ip0, sizeof (ip4_header_t));
2419             }
2420           else
2421             /* Guess we are only writing on simple Ethernet header. */
2422             vnet_rewrite_one_header (adj0[0], ip0,
2423                                      sizeof (ethernet_header_t));
2424
2425           /*
2426            * Bump the per-adjacency counters
2427            */
2428           if (do_counters)
2429             vlib_increment_combined_counter
2430               (&adjacency_counters,
2431                thread_index,
2432                adj_index0, 1, vlib_buffer_length_in_chain (vm,
2433                                                            b[0]) + rw_len0);
2434
2435           if (is_midchain)
2436             adj_midchain_fixup (vm, adj0, b[0], VNET_LINK_IP4);
2437
2438           if (is_mcast)
2439             /* copy bytes from the IP address into the MAC rewrite */
2440             vnet_ip_mcast_fixup_header (IP4_MCAST_ADDR_MASK,
2441                                         adj0->rewrite_header.dst_mcast_offset,
2442                                         &ip0->dst_address.as_u32, (u8 *) ip0);
2443         }
2444       else
2445         {
2446           b[0]->error = error_node->errors[error0];
2447           if (error0 == IP4_ERROR_MTU_EXCEEDED)
2448             ip4_ttl_inc (b[0], ip0);
2449         }
2450
2451       next += 1;
2452       b += 1;
2453       n_left_from -= 1;
2454     }
2455 #endif
2456
2457   while (n_left_from > 0)
2458     {
2459       ip_adjacency_t *adj0;
2460       ip4_header_t *ip0;
2461       u32 rw_len0, adj_index0, error0;
2462       u32 tx_sw_if_index0;
2463
2464       adj_index0 = vnet_buffer (b[0])->ip.adj_index[VLIB_TX];
2465
2466       adj0 = adj_get (adj_index0);
2467
2468       if (do_counters)
2469         vlib_prefetch_combined_counter (&adjacency_counters,
2470                                         thread_index, adj_index0);
2471
2472       ip0 = vlib_buffer_get_current (b[0]);
2473
2474       error0 = IP4_ERROR_NONE;
2475
2476       ip4_ttl_and_checksum_check (b[0], ip0, next + 0, &error0);
2477
2478
2479       /* Update packet buffer attributes/set output interface. */
2480       rw_len0 = adj0[0].rewrite_header.data_bytes;
2481       vnet_buffer (b[0])->ip.save_rewrite_length = rw_len0;
2482
2483       /* Check MTU of outgoing interface. */
2484       u16 ip0_len = clib_net_to_host_u16 (ip0->length);
2485       if (b[0]->flags & VNET_BUFFER_F_GSO)
2486         ip0_len = gso_mtu_sz (b[0]);
2487
2488       ip4_mtu_check (b[0], ip0_len,
2489                      adj0[0].rewrite_header.max_l3_packet_bytes,
2490                      ip0->flags_and_fragment_offset &
2491                      clib_host_to_net_u16 (IP4_HEADER_FLAG_DONT_FRAGMENT),
2492                      next + 0, is_midchain, &error0);
2493
2494       if (is_mcast)
2495         {
2496           error0 = ((adj0[0].rewrite_header.sw_if_index ==
2497                      vnet_buffer (b[0])->sw_if_index[VLIB_RX]) ?
2498                     IP4_ERROR_SAME_INTERFACE : error0);
2499         }
2500
2501       /* Don't adjust the buffer for ttl issue; icmp-error node wants
2502        * to see the IP header */
2503       if (PREDICT_TRUE (error0 == IP4_ERROR_NONE))
2504         {
2505           u32 next_index = adj0[0].rewrite_header.next_index;
2506           vlib_buffer_advance (b[0], -(word) rw_len0);
2507           tx_sw_if_index0 = adj0[0].rewrite_header.sw_if_index;
2508           vnet_buffer (b[0])->sw_if_index[VLIB_TX] = tx_sw_if_index0;
2509
2510           if (PREDICT_FALSE
2511               (adj0[0].rewrite_header.flags & VNET_REWRITE_HAS_FEATURES))
2512             vnet_feature_arc_start_w_cfg_index (lm->output_feature_arc_index,
2513                                                 tx_sw_if_index0,
2514                                                 &next_index, b[0],
2515                                                 adj0->ia_cfg_index);
2516           next[0] = next_index;
2517
2518           if (is_midchain)
2519             {
2520               /* this acts on the packet that is about to be encapped */
2521               vnet_calc_checksums_inline (vm, b[0], 1 /* is_ip4 */ ,
2522                                           0 /* is_ip6 */ );
2523
2524               /* Guess we are only writing on ipv4 header. */
2525               vnet_rewrite_one_header (adj0[0], ip0, sizeof (ip4_header_t));
2526             }
2527           else
2528             /* Guess we are only writing on simple Ethernet header. */
2529             vnet_rewrite_one_header (adj0[0], ip0,
2530                                      sizeof (ethernet_header_t));
2531
2532           if (do_counters)
2533             vlib_increment_combined_counter
2534               (&adjacency_counters,
2535                thread_index, adj_index0, 1,
2536                vlib_buffer_length_in_chain (vm, b[0]) + rw_len0);
2537
2538           if (is_midchain)
2539             adj_midchain_fixup (vm, adj0, b[0], VNET_LINK_IP4);
2540
2541           if (is_mcast)
2542             /* copy bytes from the IP address into the MAC rewrite */
2543             vnet_ip_mcast_fixup_header (IP4_MCAST_ADDR_MASK,
2544                                         adj0->rewrite_header.dst_mcast_offset,
2545                                         &ip0->dst_address.as_u32, (u8 *) ip0);
2546         }
2547       else
2548         {
2549           b[0]->error = error_node->errors[error0];
2550           /* undo the TTL decrement - we'll be back to do it again */
2551           if (error0 == IP4_ERROR_MTU_EXCEEDED)
2552             ip4_ttl_inc (b[0], ip0);
2553         }
2554
2555       next += 1;
2556       b += 1;
2557       n_left_from -= 1;
2558     }
2559
2560
2561   /* Need to do trace after rewrites to pick up new packet data. */
2562   if (node->flags & VLIB_NODE_FLAG_TRACE)
2563     ip4_forward_next_trace (vm, node, frame, VLIB_TX);
2564
2565   vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
2566   return frame->n_vectors;
2567 }
2568
2569 /** @brief IPv4 rewrite node.
2570     @node ip4-rewrite
2571
2572     This is the IPv4 transit-rewrite node: decrement TTL, fix the ipv4
2573     header checksum, fetch the ip adjacency, check the outbound mtu,
2574     apply the adjacency rewrite, and send pkts to the adjacency
2575     rewrite header's rewrite_next_index.
2576
2577     @param vm vlib_main_t corresponding to the current thread
2578     @param node vlib_node_runtime_t
2579     @param frame vlib_frame_t whose contents should be dispatched
2580
2581     @par Graph mechanics: buffer metadata, next index usage
2582
2583     @em Uses:
2584     - <code>vnet_buffer(b)->ip.adj_index[VLIB_TX]</code>
2585         - the rewrite adjacency index
2586     - <code>adj->lookup_next_index</code>
2587         - Must be IP_LOOKUP_NEXT_REWRITE or IP_LOOKUP_NEXT_ARP, otherwise
2588           the packet will be dropped.
2589     - <code>adj->rewrite_header</code>
2590         - Rewrite string length, rewrite string, next_index
2591
2592     @em Sets:
2593     - <code>b->current_data, b->current_length</code>
2594         - Updated net of applying the rewrite string
2595
2596     <em>Next Indices:</em>
2597     - <code> adj->rewrite_header.next_index </code>
2598       or @c ip4-drop
2599 */
2600
2601 VLIB_NODE_FN (ip4_rewrite_node) (vlib_main_t * vm, vlib_node_runtime_t * node,
2602                                  vlib_frame_t * frame)
2603 {
2604   if (adj_are_counters_enabled ())
2605     return ip4_rewrite_inline (vm, node, frame, 1, 0, 0);
2606   else
2607     return ip4_rewrite_inline (vm, node, frame, 0, 0, 0);
2608 }
2609
2610 VLIB_NODE_FN (ip4_rewrite_bcast_node) (vlib_main_t * vm,
2611                                        vlib_node_runtime_t * node,
2612                                        vlib_frame_t * frame)
2613 {
2614   if (adj_are_counters_enabled ())
2615     return ip4_rewrite_inline (vm, node, frame, 1, 0, 0);
2616   else
2617     return ip4_rewrite_inline (vm, node, frame, 0, 0, 0);
2618 }
2619
2620 VLIB_NODE_FN (ip4_midchain_node) (vlib_main_t * vm,
2621                                   vlib_node_runtime_t * node,
2622                                   vlib_frame_t * frame)
2623 {
2624   if (adj_are_counters_enabled ())
2625     return ip4_rewrite_inline (vm, node, frame, 1, 1, 0);
2626   else
2627     return ip4_rewrite_inline (vm, node, frame, 0, 1, 0);
2628 }
2629
2630 VLIB_NODE_FN (ip4_rewrite_mcast_node) (vlib_main_t * vm,
2631                                        vlib_node_runtime_t * node,
2632                                        vlib_frame_t * frame)
2633 {
2634   if (adj_are_counters_enabled ())
2635     return ip4_rewrite_inline (vm, node, frame, 1, 0, 1);
2636   else
2637     return ip4_rewrite_inline (vm, node, frame, 0, 0, 1);
2638 }
2639
2640 VLIB_NODE_FN (ip4_mcast_midchain_node) (vlib_main_t * vm,
2641                                         vlib_node_runtime_t * node,
2642                                         vlib_frame_t * frame)
2643 {
2644   if (adj_are_counters_enabled ())
2645     return ip4_rewrite_inline (vm, node, frame, 1, 1, 1);
2646   else
2647     return ip4_rewrite_inline (vm, node, frame, 0, 1, 1);
2648 }
2649
2650 /* *INDENT-OFF* */
2651 VLIB_REGISTER_NODE (ip4_rewrite_node) = {
2652   .name = "ip4-rewrite",
2653   .vector_size = sizeof (u32),
2654
2655   .format_trace = format_ip4_rewrite_trace,
2656
2657   .n_next_nodes = IP4_REWRITE_N_NEXT,
2658   .next_nodes = {
2659     [IP4_REWRITE_NEXT_DROP] = "ip4-drop",
2660     [IP4_REWRITE_NEXT_ICMP_ERROR] = "ip4-icmp-error",
2661     [IP4_REWRITE_NEXT_FRAGMENT] = "ip4-frag",
2662   },
2663 };
2664
2665 VLIB_REGISTER_NODE (ip4_rewrite_bcast_node) = {
2666   .name = "ip4-rewrite-bcast",
2667   .vector_size = sizeof (u32),
2668
2669   .format_trace = format_ip4_rewrite_trace,
2670   .sibling_of = "ip4-rewrite",
2671 };
2672
2673 VLIB_REGISTER_NODE (ip4_rewrite_mcast_node) = {
2674   .name = "ip4-rewrite-mcast",
2675   .vector_size = sizeof (u32),
2676
2677   .format_trace = format_ip4_rewrite_trace,
2678   .sibling_of = "ip4-rewrite",
2679 };
2680
2681 VLIB_REGISTER_NODE (ip4_mcast_midchain_node) = {
2682   .name = "ip4-mcast-midchain",
2683   .vector_size = sizeof (u32),
2684
2685   .format_trace = format_ip4_rewrite_trace,
2686   .sibling_of = "ip4-rewrite",
2687 };
2688
2689 VLIB_REGISTER_NODE (ip4_midchain_node) = {
2690   .name = "ip4-midchain",
2691   .vector_size = sizeof (u32),
2692   .format_trace = format_ip4_rewrite_trace,
2693   .sibling_of = "ip4-rewrite",
2694 };
2695 /* *INDENT-ON */
2696
2697 static clib_error_t *
2698 set_ip_flow_hash_command_fn (vlib_main_t * vm,
2699                              unformat_input_t * input,
2700                              vlib_cli_command_t * cmd)
2701 {
2702   int matched = 0;
2703   u32 table_id = 0;
2704   u32 flow_hash_config = 0;
2705   int rv;
2706
2707   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
2708     {
2709       if (unformat (input, "table %d", &table_id))
2710         matched = 1;
2711 #define _(a, b, v)                                                            \
2712   else if (unformat (input, #a))                                              \
2713   {                                                                           \
2714     flow_hash_config |= v;                                                    \
2715     matched = 1;                                                              \
2716   }
2717       foreach_flow_hash_bit
2718 #undef _
2719         else
2720         break;
2721     }
2722
2723   if (matched == 0)
2724     return clib_error_return (0, "unknown input `%U'",
2725                               format_unformat_error, input);
2726
2727   rv = ip_flow_hash_set (AF_IP4, table_id, flow_hash_config);
2728   switch (rv)
2729     {
2730     case 0:
2731       break;
2732
2733     case VNET_API_ERROR_NO_SUCH_FIB:
2734       return clib_error_return (0, "no such FIB table %d", table_id);
2735
2736     default:
2737       clib_warning ("BUG: illegal flow hash config 0x%x", flow_hash_config);
2738       break;
2739     }
2740
2741   return 0;
2742 }
2743
2744 /*?
2745  * Configure the set of IPv4 fields used by the flow hash.
2746  *
2747  * @cliexpar
2748  * Example of how to set the flow hash on a given table:
2749  * @cliexcmd{set ip flow-hash table 7 dst sport dport proto}
2750  * Example of display the configured flow hash:
2751  * @cliexstart{show ip fib}
2752  * ipv4-VRF:0, fib_index 0, flow hash: src dst sport dport proto
2753  * 0.0.0.0/0
2754  *   unicast-ip4-chain
2755  *   [@0]: dpo-load-balance: [index:0 buckets:1 uRPF:0 to:[0:0]]
2756  *     [0] [@0]: dpo-drop ip6
2757  * 0.0.0.0/32
2758  *   unicast-ip4-chain
2759  *   [@0]: dpo-load-balance: [index:1 buckets:1 uRPF:1 to:[0:0]]
2760  *     [0] [@0]: dpo-drop ip6
2761  * 224.0.0.0/8
2762  *   unicast-ip4-chain
2763  *   [@0]: dpo-load-balance: [index:3 buckets:1 uRPF:3 to:[0:0]]
2764  *     [0] [@0]: dpo-drop ip6
2765  * 6.0.1.2/32
2766  *   unicast-ip4-chain
2767  *   [@0]: dpo-load-balance: [index:30 buckets:1 uRPF:29 to:[0:0]]
2768  *     [0] [@3]: arp-ipv4: via 6.0.0.1 af_packet0
2769  * 7.0.0.1/32
2770  *   unicast-ip4-chain
2771  *   [@0]: dpo-load-balance: [index:31 buckets:4 uRPF:30 to:[0:0]]
2772  *     [0] [@3]: arp-ipv4: via 6.0.0.2 af_packet0
2773  *     [1] [@3]: arp-ipv4: via 6.0.0.2 af_packet0
2774  *     [2] [@3]: arp-ipv4: via 6.0.0.2 af_packet0
2775  *     [3] [@3]: arp-ipv4: via 6.0.0.1 af_packet0
2776  * 240.0.0.0/8
2777  *   unicast-ip4-chain
2778  *   [@0]: dpo-load-balance: [index:2 buckets:1 uRPF:2 to:[0:0]]
2779  *     [0] [@0]: dpo-drop ip6
2780  * 255.255.255.255/32
2781  *   unicast-ip4-chain
2782  *   [@0]: dpo-load-balance: [index:4 buckets:1 uRPF:4 to:[0:0]]
2783  *     [0] [@0]: dpo-drop ip6
2784  * ipv4-VRF:7, fib_index 1, flow hash: dst sport dport proto
2785  * 0.0.0.0/0
2786  *   unicast-ip4-chain
2787  *   [@0]: dpo-load-balance: [index:12 buckets:1 uRPF:11 to:[0:0]]
2788  *     [0] [@0]: dpo-drop ip6
2789  * 0.0.0.0/32
2790  *   unicast-ip4-chain
2791  *   [@0]: dpo-load-balance: [index:13 buckets:1 uRPF:12 to:[0:0]]
2792  *     [0] [@0]: dpo-drop ip6
2793  * 172.16.1.0/24
2794  *   unicast-ip4-chain
2795  *   [@0]: dpo-load-balance: [index:17 buckets:1 uRPF:16 to:[0:0]]
2796  *     [0] [@4]: ipv4-glean: af_packet0
2797  * 172.16.1.1/32
2798  *   unicast-ip4-chain
2799  *   [@0]: dpo-load-balance: [index:18 buckets:1 uRPF:17 to:[1:84]]
2800  *     [0] [@2]: dpo-receive: 172.16.1.1 on af_packet0
2801  * 172.16.1.2/32
2802  *   unicast-ip4-chain
2803  *   [@0]: dpo-load-balance: [index:21 buckets:1 uRPF:20 to:[0:0]]
2804  *     [0] [@5]: ipv4 via 172.16.1.2 af_packet0: IP4: 02:fe:9e:70:7a:2b -> 26:a5:f6:9c:3a:36
2805  * 172.16.2.0/24
2806  *   unicast-ip4-chain
2807  *   [@0]: dpo-load-balance: [index:19 buckets:1 uRPF:18 to:[0:0]]
2808  *     [0] [@4]: ipv4-glean: af_packet1
2809  * 172.16.2.1/32
2810  *   unicast-ip4-chain
2811  *   [@0]: dpo-load-balance: [index:20 buckets:1 uRPF:19 to:[0:0]]
2812  *     [0] [@2]: dpo-receive: 172.16.2.1 on af_packet1
2813  * 224.0.0.0/8
2814  *   unicast-ip4-chain
2815  *   [@0]: dpo-load-balance: [index:15 buckets:1 uRPF:14 to:[0:0]]
2816  *     [0] [@0]: dpo-drop ip6
2817  * 240.0.0.0/8
2818  *   unicast-ip4-chain
2819  *   [@0]: dpo-load-balance: [index:14 buckets:1 uRPF:13 to:[0:0]]
2820  *     [0] [@0]: dpo-drop ip6
2821  * 255.255.255.255/32
2822  *   unicast-ip4-chain
2823  *   [@0]: dpo-load-balance: [index:16 buckets:1 uRPF:15 to:[0:0]]
2824  *     [0] [@0]: dpo-drop ip6
2825  * @cliexend
2826 ?*/
2827 /* *INDENT-OFF* */
2828 VLIB_CLI_COMMAND (set_ip_flow_hash_command, static) =
2829 {
2830   .path = "set ip flow-hash",
2831   .short_help =
2832   "set ip flow-hash table <table-id> [src] [dst] [sport] [dport] [proto] [reverse]",
2833   .function = set_ip_flow_hash_command_fn,
2834 };
2835 /* *INDENT-ON* */
2836
2837 #ifndef CLIB_MARCH_VARIANT
2838 int
2839 vnet_set_ip4_classify_intfc (vlib_main_t * vm, u32 sw_if_index,
2840                              u32 table_index)
2841 {
2842   vnet_main_t *vnm = vnet_get_main ();
2843   vnet_interface_main_t *im = &vnm->interface_main;
2844   ip4_main_t *ipm = &ip4_main;
2845   ip_lookup_main_t *lm = &ipm->lookup_main;
2846   vnet_classify_main_t *cm = &vnet_classify_main;
2847   ip4_address_t *if_addr;
2848
2849   if (pool_is_free_index (im->sw_interfaces, sw_if_index))
2850     return VNET_API_ERROR_NO_MATCHING_INTERFACE;
2851
2852   if (table_index != ~0 && pool_is_free_index (cm->tables, table_index))
2853     return VNET_API_ERROR_NO_SUCH_ENTRY;
2854
2855   vec_validate (lm->classify_table_index_by_sw_if_index, sw_if_index);
2856   lm->classify_table_index_by_sw_if_index[sw_if_index] = table_index;
2857
2858   if_addr = ip4_interface_first_address (ipm, sw_if_index, NULL);
2859
2860   if (NULL != if_addr)
2861     {
2862       fib_prefix_t pfx = {
2863         .fp_len = 32,
2864         .fp_proto = FIB_PROTOCOL_IP4,
2865         .fp_addr.ip4 = *if_addr,
2866       };
2867       u32 fib_index;
2868
2869       fib_index = fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
2870                                                        sw_if_index);
2871
2872
2873       if (table_index != (u32) ~ 0)
2874         {
2875           dpo_id_t dpo = DPO_INVALID;
2876
2877           dpo_set (&dpo,
2878                    DPO_CLASSIFY,
2879                    DPO_PROTO_IP4,
2880                    classify_dpo_create (DPO_PROTO_IP4, table_index));
2881
2882           fib_table_entry_special_dpo_add (fib_index,
2883                                            &pfx,
2884                                            FIB_SOURCE_CLASSIFY,
2885                                            FIB_ENTRY_FLAG_NONE, &dpo);
2886           dpo_reset (&dpo);
2887         }
2888       else
2889         {
2890           fib_table_entry_special_remove (fib_index,
2891                                           &pfx, FIB_SOURCE_CLASSIFY);
2892         }
2893     }
2894
2895   return 0;
2896 }
2897 #endif
2898
2899 static clib_error_t *
2900 set_ip_classify_command_fn (vlib_main_t * vm,
2901                             unformat_input_t * input,
2902                             vlib_cli_command_t * cmd)
2903 {
2904   u32 table_index = ~0;
2905   int table_index_set = 0;
2906   u32 sw_if_index = ~0;
2907   int rv;
2908
2909   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
2910     {
2911       if (unformat (input, "table-index %d", &table_index))
2912         table_index_set = 1;
2913       else if (unformat (input, "intfc %U", unformat_vnet_sw_interface,
2914                          vnet_get_main (), &sw_if_index))
2915         ;
2916       else
2917         break;
2918     }
2919
2920   if (table_index_set == 0)
2921     return clib_error_return (0, "classify table-index must be specified");
2922
2923   if (sw_if_index == ~0)
2924     return clib_error_return (0, "interface / subif must be specified");
2925
2926   rv = vnet_set_ip4_classify_intfc (vm, sw_if_index, table_index);
2927
2928   switch (rv)
2929     {
2930     case 0:
2931       break;
2932
2933     case VNET_API_ERROR_NO_MATCHING_INTERFACE:
2934       return clib_error_return (0, "No such interface");
2935
2936     case VNET_API_ERROR_NO_SUCH_ENTRY:
2937       return clib_error_return (0, "No such classifier table");
2938     }
2939   return 0;
2940 }
2941
2942 /*?
2943  * Assign a classification table to an interface. The classification
2944  * table is created using the '<em>classify table</em>' and '<em>classify session</em>'
2945  * commands. Once the table is create, use this command to filter packets
2946  * on an interface.
2947  *
2948  * @cliexpar
2949  * Example of how to assign a classification table to an interface:
2950  * @cliexcmd{set ip classify intfc GigabitEthernet2/0/0 table-index 1}
2951 ?*/
2952 /* *INDENT-OFF* */
2953 VLIB_CLI_COMMAND (set_ip_classify_command, static) =
2954 {
2955     .path = "set ip classify",
2956     .short_help =
2957     "set ip classify intfc <interface> table-index <classify-idx>",
2958     .function = set_ip_classify_command_fn,
2959 };
2960 /* *INDENT-ON* */
2961
2962 /*
2963  * fd.io coding-style-patch-verification: ON
2964  *
2965  * Local Variables:
2966  * eval: (c-set-style "gnu")
2967  * End:
2968  */