src/vnet/ip/ip4_forward.h

   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.h: 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 #ifndef __included_ip4_forward_h__
  41 #define __included_ip4_forward_h__
  42
  43 #include <vnet/fib/ip4_fib.h>
  44 #include <vnet/dpo/load_balance_map.h>
  45
  46 /**
  47  * @file
  48  * @brief IPv4 Forwarding.
  49  *
  50  * This file contains the source code for IPv4 forwarding.
  51  */
  52
  53 always_inline uword
  54 ip4_lookup_inline (vlib_main_t * vm,
  55                    vlib_node_runtime_t * node,
  56                    vlib_frame_t * frame,
  57                    int lookup_for_responses_to_locally_received_packets)
  58 {
  59   ip4_main_t *im = &ip4_main;
  60   vlib_combined_counter_main_t *cm = &load_balance_main.lbm_to_counters;
  61   u32 n_left_from, n_left_to_next, *from, *to_next;
  62   ip_lookup_next_t next;
  63   u32 thread_index = vlib_get_thread_index ();
  64
  65   from = vlib_frame_vector_args (frame);
  66   n_left_from = frame->n_vectors;
  67   next = node->cached_next_index;
  68
  69   while (n_left_from > 0)
  70     {
  71       vlib_get_next_frame (vm, node, next, to_next, n_left_to_next);
  72
  73       while (n_left_from >= 8 && n_left_to_next >= 4)
  74         {
  75           vlib_buffer_t *p0, *p1, *p2, *p3;
  76           ip4_header_t *ip0, *ip1, *ip2, *ip3;
  77           ip_lookup_next_t next0, next1, next2, next3;
  78           const load_balance_t *lb0, *lb1, *lb2, *lb3;
  79           ip4_fib_mtrie_t *mtrie0, *mtrie1, *mtrie2, *mtrie3;
  80           ip4_fib_mtrie_leaf_t leaf0, leaf1, leaf2, leaf3;
  81           ip4_address_t *dst_addr0, *dst_addr1, *dst_addr2, *dst_addr3;
  82           u32 pi0, pi1, pi2, pi3, lb_index0, lb_index1, lb_index2, lb_index3;
  83           flow_hash_config_t flow_hash_config0, flow_hash_config1;
  84           flow_hash_config_t flow_hash_config2, flow_hash_config3;
  85           u32 hash_c0, hash_c1, hash_c2, hash_c3;
  86           const dpo_id_t *dpo0, *dpo1, *dpo2, *dpo3;
  87
  88           /* Prefetch next iteration. */
  89           {
  90             vlib_buffer_t *p4, *p5, *p6, *p7;
  91
  92             p4 = vlib_get_buffer (vm, from[4]);
  93             p5 = vlib_get_buffer (vm, from[5]);
  94             p6 = vlib_get_buffer (vm, from[6]);
  95             p7 = vlib_get_buffer (vm, from[7]);
  96
  97             vlib_prefetch_buffer_header (p4, LOAD);
  98             vlib_prefetch_buffer_header (p5, LOAD);
  99             vlib_prefetch_buffer_header (p6, LOAD);
 100             vlib_prefetch_buffer_header (p7, LOAD);
 101
 102             CLIB_PREFETCH (p4->data, sizeof (ip0[0]), LOAD);
 103             CLIB_PREFETCH (p5->data, sizeof (ip0[0]), LOAD);
 104             CLIB_PREFETCH (p6->data, sizeof (ip0[0]), LOAD);
 105             CLIB_PREFETCH (p7->data, sizeof (ip0[0]), LOAD);
 106           }
 107
 108           pi0 = to_next[0] = from[0];
 109           pi1 = to_next[1] = from[1];
 110           pi2 = to_next[2] = from[2];
 111           pi3 = to_next[3] = from[3];
 112
 113           from += 4;
 114           to_next += 4;
 115           n_left_to_next -= 4;
 116           n_left_from -= 4;
 117
 118           p0 = vlib_get_buffer (vm, pi0);
 119           p1 = vlib_get_buffer (vm, pi1);
 120           p2 = vlib_get_buffer (vm, pi2);
 121           p3 = vlib_get_buffer (vm, pi3);
 122
 123           ip0 = vlib_buffer_get_current (p0);
 124           ip1 = vlib_buffer_get_current (p1);
 125           ip2 = vlib_buffer_get_current (p2);
 126           ip3 = vlib_buffer_get_current (p3);
 127
 128           dst_addr0 = &ip0->dst_address;
 129           dst_addr1 = &ip1->dst_address;
 130           dst_addr2 = &ip2->dst_address;
 131           dst_addr3 = &ip3->dst_address;
 132
 133           ip_lookup_set_buffer_fib_index (im->fib_index_by_sw_if_index, p0);
 134           ip_lookup_set_buffer_fib_index (im->fib_index_by_sw_if_index, p1);
 135           ip_lookup_set_buffer_fib_index (im->fib_index_by_sw_if_index, p2);
 136           ip_lookup_set_buffer_fib_index (im->fib_index_by_sw_if_index, p3);
 137
 138           if (!lookup_for_responses_to_locally_received_packets)
 139             {
 140               mtrie0 = &ip4_fib_get (vnet_buffer (p0)->ip.fib_index)->mtrie;
 141               mtrie1 = &ip4_fib_get (vnet_buffer (p1)->ip.fib_index)->mtrie;
 142               mtrie2 = &ip4_fib_get (vnet_buffer (p2)->ip.fib_index)->mtrie;
 143               mtrie3 = &ip4_fib_get (vnet_buffer (p3)->ip.fib_index)->mtrie;
 144
 145               leaf0 = ip4_fib_mtrie_lookup_step_one (mtrie0, dst_addr0);
 146               leaf1 = ip4_fib_mtrie_lookup_step_one (mtrie1, dst_addr1);
 147               leaf2 = ip4_fib_mtrie_lookup_step_one (mtrie2, dst_addr2);
 148               leaf3 = ip4_fib_mtrie_lookup_step_one (mtrie3, dst_addr3);
 149             }
 150
 151           if (!lookup_for_responses_to_locally_received_packets)
 152             {
 153               leaf0 = ip4_fib_mtrie_lookup_step (mtrie0, leaf0, dst_addr0, 2);
 154               leaf1 = ip4_fib_mtrie_lookup_step (mtrie1, leaf1, dst_addr1, 2);
 155               leaf2 = ip4_fib_mtrie_lookup_step (mtrie2, leaf2, dst_addr2, 2);
 156               leaf3 = ip4_fib_mtrie_lookup_step (mtrie3, leaf3, dst_addr3, 2);
 157             }
 158
 159           if (!lookup_for_responses_to_locally_received_packets)
 160             {
 161               leaf0 = ip4_fib_mtrie_lookup_step (mtrie0, leaf0, dst_addr0, 3);
 162               leaf1 = ip4_fib_mtrie_lookup_step (mtrie1, leaf1, dst_addr1, 3);
 163               leaf2 = ip4_fib_mtrie_lookup_step (mtrie2, leaf2, dst_addr2, 3);
 164               leaf3 = ip4_fib_mtrie_lookup_step (mtrie3, leaf3, dst_addr3, 3);
 165             }
 166
 167           if (lookup_for_responses_to_locally_received_packets)
 168             {
 169               lb_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_RX];
 170               lb_index1 = vnet_buffer (p1)->ip.adj_index[VLIB_RX];
 171               lb_index2 = vnet_buffer (p2)->ip.adj_index[VLIB_RX];
 172               lb_index3 = vnet_buffer (p3)->ip.adj_index[VLIB_RX];
 173             }
 174           else
 175             {
 176               lb_index0 = ip4_fib_mtrie_leaf_get_adj_index (leaf0);
 177               lb_index1 = ip4_fib_mtrie_leaf_get_adj_index (leaf1);
 178               lb_index2 = ip4_fib_mtrie_leaf_get_adj_index (leaf2);
 179               lb_index3 = ip4_fib_mtrie_leaf_get_adj_index (leaf3);
 180             }
 181
 182           ASSERT (lb_index0 && lb_index1 && lb_index2 && lb_index3);
 183           lb0 = load_balance_get (lb_index0);
 184           lb1 = load_balance_get (lb_index1);
 185           lb2 = load_balance_get (lb_index2);
 186           lb3 = load_balance_get (lb_index3);
 187
 188           ASSERT (lb0->lb_n_buckets > 0);
 189           ASSERT (is_pow2 (lb0->lb_n_buckets));
 190           ASSERT (lb1->lb_n_buckets > 0);
 191           ASSERT (is_pow2 (lb1->lb_n_buckets));
 192           ASSERT (lb2->lb_n_buckets > 0);
 193           ASSERT (is_pow2 (lb2->lb_n_buckets));
 194           ASSERT (lb3->lb_n_buckets > 0);
 195           ASSERT (is_pow2 (lb3->lb_n_buckets));
 196
 197           /* Use flow hash to compute multipath adjacency. */
 198           hash_c0 = vnet_buffer (p0)->ip.flow_hash = 0;
 199           hash_c1 = vnet_buffer (p1)->ip.flow_hash = 0;
 200           hash_c2 = vnet_buffer (p2)->ip.flow_hash = 0;
 201           hash_c3 = vnet_buffer (p3)->ip.flow_hash = 0;
 202           if (PREDICT_FALSE (lb0->lb_n_buckets > 1))
 203             {
 204               flow_hash_config0 = lb0->lb_hash_config;
 205               hash_c0 = vnet_buffer (p0)->ip.flow_hash =
 206                 ip4_compute_flow_hash (ip0, flow_hash_config0);
 207               dpo0 =
 208                 load_balance_get_fwd_bucket (lb0,
 209                                              (hash_c0 &
 210                                               (lb0->lb_n_buckets_minus_1)));
 211             }
 212           else
 213             {
 214               dpo0 = load_balance_get_bucket_i (lb0, 0);
 215             }
 216           if (PREDICT_FALSE (lb1->lb_n_buckets > 1))
 217             {
 218               flow_hash_config1 = lb1->lb_hash_config;
 219               hash_c1 = vnet_buffer (p1)->ip.flow_hash =
 220                 ip4_compute_flow_hash (ip1, flow_hash_config1);
 221               dpo1 =
 222                 load_balance_get_fwd_bucket (lb1,
 223                                              (hash_c1 &
 224                                               (lb1->lb_n_buckets_minus_1)));
 225             }
 226           else
 227             {
 228               dpo1 = load_balance_get_bucket_i (lb1, 0);
 229             }
 230           if (PREDICT_FALSE (lb2->lb_n_buckets > 1))
 231             {
 232               flow_hash_config2 = lb2->lb_hash_config;
 233               hash_c2 = vnet_buffer (p2)->ip.flow_hash =
 234                 ip4_compute_flow_hash (ip2, flow_hash_config2);
 235               dpo2 =
 236                 load_balance_get_fwd_bucket (lb2,
 237                                              (hash_c2 &
 238                                               (lb2->lb_n_buckets_minus_1)));
 239             }
 240           else
 241             {
 242               dpo2 = load_balance_get_bucket_i (lb2, 0);
 243             }
 244           if (PREDICT_FALSE (lb3->lb_n_buckets > 1))
 245             {
 246               flow_hash_config3 = lb3->lb_hash_config;
 247               hash_c3 = vnet_buffer (p3)->ip.flow_hash =
 248                 ip4_compute_flow_hash (ip3, flow_hash_config3);
 249               dpo3 =
 250                 load_balance_get_fwd_bucket (lb3,
 251                                              (hash_c3 &
 252                                               (lb3->lb_n_buckets_minus_1)));
 253             }
 254           else
 255             {
 256               dpo3 = load_balance_get_bucket_i (lb3, 0);
 257             }
 258
 259           next0 = dpo0->dpoi_next_node;
 260           vnet_buffer (p0)->ip.adj_index[VLIB_TX] = dpo0->dpoi_index;
 261           next1 = dpo1->dpoi_next_node;
 262           vnet_buffer (p1)->ip.adj_index[VLIB_TX] = dpo1->dpoi_index;
 263           next2 = dpo2->dpoi_next_node;
 264           vnet_buffer (p2)->ip.adj_index[VLIB_TX] = dpo2->dpoi_index;
 265           next3 = dpo3->dpoi_next_node;
 266           vnet_buffer (p3)->ip.adj_index[VLIB_TX] = dpo3->dpoi_index;
 267
 268           vlib_increment_combined_counter
 269             (cm, thread_index, lb_index0, 1,
 270              vlib_buffer_length_in_chain (vm, p0));
 271           vlib_increment_combined_counter
 272             (cm, thread_index, lb_index1, 1,
 273              vlib_buffer_length_in_chain (vm, p1));
 274           vlib_increment_combined_counter
 275             (cm, thread_index, lb_index2, 1,
 276              vlib_buffer_length_in_chain (vm, p2));
 277           vlib_increment_combined_counter
 278             (cm, thread_index, lb_index3, 1,
 279              vlib_buffer_length_in_chain (vm, p3));
 280
 281           vlib_validate_buffer_enqueue_x4 (vm, node, next,
 282                                            to_next, n_left_to_next,
 283                                            pi0, pi1, pi2, pi3,
 284                                            next0, next1, next2, next3);
 285         }
 286
 287       while (n_left_from > 0 && n_left_to_next > 0)
 288         {
 289           vlib_buffer_t *p0;
 290           ip4_header_t *ip0;
 291           ip_lookup_next_t next0;
 292           const load_balance_t *lb0;
 293           ip4_fib_mtrie_t *mtrie0;
 294           ip4_fib_mtrie_leaf_t leaf0;
 295           ip4_address_t *dst_addr0;
 296           u32 pi0, lbi0;
 297           flow_hash_config_t flow_hash_config0;
 298           const dpo_id_t *dpo0;
 299           u32 hash_c0;
 300
 301           pi0 = from[0];
 302           to_next[0] = pi0;
 303
 304           p0 = vlib_get_buffer (vm, pi0);
 305           ip0 = vlib_buffer_get_current (p0);
 306           dst_addr0 = &ip0->dst_address;
 307           ip_lookup_set_buffer_fib_index (im->fib_index_by_sw_if_index, p0);
 308
 309           if (!lookup_for_responses_to_locally_received_packets)
 310             {
 311               mtrie0 = &ip4_fib_get (vnet_buffer (p0)->ip.fib_index)->mtrie;
 312               leaf0 = ip4_fib_mtrie_lookup_step_one (mtrie0, dst_addr0);
 313             }
 314
 315           if (!lookup_for_responses_to_locally_received_packets)
 316             leaf0 = ip4_fib_mtrie_lookup_step (mtrie0, leaf0, dst_addr0, 2);
 317
 318           if (!lookup_for_responses_to_locally_received_packets)
 319             leaf0 = ip4_fib_mtrie_lookup_step (mtrie0, leaf0, dst_addr0, 3);
 320
 321           if (lookup_for_responses_to_locally_received_packets)
 322             lbi0 = vnet_buffer (p0)->ip.adj_index[VLIB_RX];
 323           else
 324             {
 325               /* Handle default route. */
 326               lbi0 = ip4_fib_mtrie_leaf_get_adj_index (leaf0);
 327             }
 328
 329           ASSERT (lbi0);
 330           lb0 = load_balance_get (lbi0);
 331
 332           ASSERT (lb0->lb_n_buckets > 0);
 333           ASSERT (is_pow2 (lb0->lb_n_buckets));
 334
 335           /* Use flow hash to compute multipath adjacency. */
 336           hash_c0 = vnet_buffer (p0)->ip.flow_hash = 0;
 337           if (PREDICT_FALSE (lb0->lb_n_buckets > 1))
 338             {
 339               flow_hash_config0 = lb0->lb_hash_config;
 340
 341               hash_c0 = vnet_buffer (p0)->ip.flow_hash =
 342                 ip4_compute_flow_hash (ip0, flow_hash_config0);
 343               dpo0 =
 344                 load_balance_get_fwd_bucket (lb0,
 345                                              (hash_c0 &
 346                                               (lb0->lb_n_buckets_minus_1)));
 347             }
 348           else
 349             {
 350               dpo0 = load_balance_get_bucket_i (lb0, 0);
 351             }
 352
 353           next0 = dpo0->dpoi_next_node;
 354           vnet_buffer (p0)->ip.adj_index[VLIB_TX] = dpo0->dpoi_index;
 355
 356           vlib_increment_combined_counter (cm, thread_index, lbi0, 1,
 357                                            vlib_buffer_length_in_chain (vm,
 358                                                                         p0));
 359
 360           from += 1;
 361           to_next += 1;
 362           n_left_to_next -= 1;
 363           n_left_from -= 1;
 364
 365           if (PREDICT_FALSE (next0 != next))
 366             {
 367               n_left_to_next += 1;
 368               vlib_put_next_frame (vm, node, next, n_left_to_next);
 369               next = next0;
 370               vlib_get_next_frame (vm, node, next, to_next, n_left_to_next);
 371               to_next[0] = pi0;
 372               to_next += 1;
 373               n_left_to_next -= 1;
 374             }
 375         }
 376
 377       vlib_put_next_frame (vm, node, next, n_left_to_next);
 378     }
 379
 380   if (node->flags & VLIB_NODE_FLAG_TRACE)
 381     ip4_forward_next_trace (vm, node, frame, VLIB_TX);
 382
 383   return frame->n_vectors;
 384 }
 385
 386 #endif /* __included_ip4_forward_h__ */
 387
 388 /*
 389  * fd.io coding-style-patch-verification: ON
 390  *
 391  * Local Variables:
 392  * eval: (c-set-style "gnu")
 393  * End:
 394  */