vnet/vnet/gre/node.c

   1 /*
   2  * node.c: gre packet processing
   3  *
   4  * Copyright (c) 2012 Cisco and/or its affiliates.
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at:
   8  *
   9  *     http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 #include <vlib/vlib.h>
  19 #include <vnet/pg/pg.h>
  20 #include <vnet/gre/gre.h>
  21 #include <vppinfra/sparse_vec.h>
  22
  23 #define foreach_gre_input_next                  \
  24 _(PUNT, "error-punt")                           \
  25 _(DROP, "error-drop")                           \
  26 _(IP4_INPUT, "ip4-input")                       \
  27 _(IP6_INPUT, "ip6-input")
  28
  29 typedef enum {
  30 #define _(s,n) GRE_INPUT_NEXT_##s,
  31   foreach_gre_input_next
  32 #undef _
  33   GRE_INPUT_N_NEXT,
  34 } gre_input_next_t;
  35
  36 typedef struct {
  37   u32 tunnel_id;
  38   u32 length;
  39   ip4_address_t src;
  40   ip4_address_t dst;
  41 } gre_rx_trace_t;
  42
  43 u8 * format_gre_rx_trace (u8 * s, va_list * args)
  44 {
  45   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  46   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  47   gre_rx_trace_t * t = va_arg (*args, gre_rx_trace_t *);
  48
  49   s = format (s, "GRE: tunnel %d len %d src %U dst %U",
  50               t->tunnel_id, clib_net_to_host_u16(t->length),
  51               format_ip4_address, &t->src.as_u8,
  52               format_ip4_address, &t->dst.as_u8);
  53   return s;
  54 }
  55
  56 typedef struct {
  57   /* Sparse vector mapping gre protocol in network byte order
  58      to next index. */
  59   u16 * next_by_protocol;
  60
  61   u32 * sparse_index_by_next_index;
  62 } gre_input_runtime_t;
  63
  64 static uword
  65 gre_input (vlib_main_t * vm,
  66            vlib_node_runtime_t * node,
  67            vlib_frame_t * from_frame)
  68 {
  69   gre_main_t * gm = &gre_main;
  70   gre_input_runtime_t * rt = (void *) node->runtime_data;
  71   __attribute__((unused)) u32 n_left_from, next_index, i_next, * from, * to_next;
  72   u64 cached_tunnel_key = (u64) ~0;
  73   u32 cached_tunnel_sw_if_index = 0, tunnel_sw_if_index;
  74   u32 cached_tunnel_fib_index = 0, tunnel_fib_index;
  75
  76   u32 cpu_index = os_get_cpu_number();
  77
  78   from = vlib_frame_vector_args (from_frame);
  79   n_left_from = from_frame->n_vectors;
  80
  81   next_index = node->cached_next_index;
  82   i_next = vec_elt (rt->sparse_index_by_next_index, next_index);
  83
  84   while (n_left_from > 0)
  85     {
  86       u32 n_left_to_next;
  87
  88       vlib_get_next_frame (vm, node, next_index,
  89                            to_next, n_left_to_next);
  90
  91       while (n_left_from >= 4 && n_left_to_next >= 2)
  92         {
  93           u32 bi0, bi1;
  94           vlib_buffer_t * b0, * b1;
  95           gre_header_t * h0, * h1;
  96           u16 version0, version1;
  97           int verr0, verr1;
  98           u32 i0, i1, next0, next1, protocol0, protocol1;
  99           ip4_header_t *ip0, *ip1;
 100
 101           /* Prefetch next iteration. */
 102           {
 103             vlib_buffer_t * p2, * p3;
 104
 105             p2 = vlib_get_buffer (vm, from[2]);
 106             p3 = vlib_get_buffer (vm, from[3]);
 107
 108             vlib_prefetch_buffer_header (p2, LOAD);
 109             vlib_prefetch_buffer_header (p3, LOAD);
 110
 111             CLIB_PREFETCH (p2->data, sizeof (h0[0]), LOAD);
 112             CLIB_PREFETCH (p3->data, sizeof (h1[0]), LOAD);
 113           }
 114
 115           bi0 = from[0];
 116           bi1 = from[1];
 117           to_next[0] = bi0;
 118           to_next[1] = bi1;
 119           from += 2;
 120           to_next += 2;
 121           n_left_to_next -= 2;
 122           n_left_from -= 2;
 123
 124           b0 = vlib_get_buffer (vm, bi0);
 125           b1 = vlib_get_buffer (vm, bi1);
 126
 127           /* ip4_local hands us the ip header, not the gre header */
 128           ip0 = vlib_buffer_get_current (b0);
 129           ip1 = vlib_buffer_get_current (b1);
 130
 131           /* Save src + dst ip4 address, e.g. for mpls-o-gre */
 132           vnet_buffer(b0)->gre.src = ip0->src_address.as_u32;
 133           vnet_buffer(b0)->gre.dst = ip0->dst_address.as_u32;
 134           vnet_buffer(b1)->gre.src = ip1->src_address.as_u32;
 135           vnet_buffer(b1)->gre.dst = ip1->dst_address.as_u32;
 136
 137           vlib_buffer_advance (b0, sizeof (*ip0));
 138           vlib_buffer_advance (b1, sizeof (*ip1));
 139
 140           h0 = vlib_buffer_get_current (b0);
 141           h1 = vlib_buffer_get_current (b1);
 142
 143           /* Index sparse array with network byte order. */
 144           protocol0 = h0->protocol;
 145           protocol1 = h1->protocol;
 146           sparse_vec_index2 (rt->next_by_protocol, protocol0, protocol1,
 147                              &i0, &i1);
 148           next0 = vec_elt(rt->next_by_protocol, i0);
 149           next1 = vec_elt(rt->next_by_protocol, i1);
 150
 151           b0->error = node->errors[next0 == SPARSE_VEC_INVALID_INDEX ? GRE_ERROR_UNKNOWN_PROTOCOL : GRE_ERROR_NONE];
 152           b1->error = node->errors[next1 == SPARSE_VEC_INVALID_INDEX ? GRE_ERROR_UNKNOWN_PROTOCOL : GRE_ERROR_NONE];
 153
 154           version0 = clib_net_to_host_u16 (h0->flags_and_version);
 155           verr0 =  version0 & GRE_VERSION_MASK;
 156           version1 = clib_net_to_host_u16 (h1->flags_and_version);
 157           verr1 =  version1 & GRE_VERSION_MASK;
 158
 159           b0->error = verr0 ? node->errors[GRE_ERROR_UNSUPPORTED_VERSION]
 160               : b0->error;
 161           next0 = verr0 ? GRE_INPUT_NEXT_DROP : next0;
 162           b1->error = verr1 ? node->errors[GRE_ERROR_UNSUPPORTED_VERSION]
 163               : b1->error;
 164           next1 = verr1 ? GRE_INPUT_NEXT_DROP : next1;
 165
 166           /* RPF check for ip4/ip6 input */
 167           if (PREDICT_FALSE(next0 == GRE_INPUT_NEXT_IP4_INPUT
 168                             || next0 == GRE_INPUT_NEXT_IP6_INPUT))
 169             {
 170               u64 key = ((u64)(vnet_buffer(b0)->gre.dst) << 32) |
 171                          (u64)(vnet_buffer(b0)->gre.src);
 172
 173               if (cached_tunnel_key != key)
 174                 {
 175                   vnet_hw_interface_t * hi;
 176                   gre_tunnel_t * t;
 177                   uword * p;
 178
 179                   ip4_main_t * ip4m = &ip4_main;
 180                   p = hash_get (gm->tunnel_by_key, key);
 181                   if (!p)
 182                     {
 183                       next0 = GRE_INPUT_NEXT_DROP;
 184                       b0->error = node->errors[GRE_ERROR_NO_SUCH_TUNNEL];
 185                       goto drop0;
 186                     }
 187                   t = pool_elt_at_index (gm->tunnels, p[0]);
 188                   hi = vnet_get_hw_interface (gm->vnet_main,
 189                             t->hw_if_index);
 190                   tunnel_sw_if_index = hi->sw_if_index;
 191                   tunnel_fib_index = vec_elt (ip4m->fib_index_by_sw_if_index,
 192                                               tunnel_sw_if_index);
 193
 194                   cached_tunnel_sw_if_index = tunnel_sw_if_index;
 195                   cached_tunnel_fib_index = tunnel_fib_index;
 196                 }
 197               else
 198                 {
 199                   tunnel_sw_if_index = cached_tunnel_sw_if_index;
 200                   tunnel_fib_index = cached_tunnel_fib_index;
 201                 }
 202
 203               u32 len = vlib_buffer_length_in_chain (vm, b0);
 204               vnet_interface_main_t *im = &gm->vnet_main->interface_main;
 205               vlib_increment_combined_counter (im->combined_sw_if_counters
 206                                                + VNET_INTERFACE_COUNTER_RX,
 207                                                cpu_index,
 208                                                tunnel_sw_if_index,
 209                                                1 /* packets */,
 210                                                len /* bytes */);
 211
 212               vnet_buffer(b0)->sw_if_index[VLIB_TX] = tunnel_fib_index;
 213             }
 214
 215 drop0:
 216           if (PREDICT_FALSE(next1 == GRE_INPUT_NEXT_IP4_INPUT
 217                             || next1 == GRE_INPUT_NEXT_IP6_INPUT))
 218             {
 219               u64 key = ((u64)(vnet_buffer(b1)->gre.dst) << 32) |
 220                          (u64)(vnet_buffer(b1)->gre.src);
 221
 222               if (cached_tunnel_key != key)
 223                 {
 224                   vnet_hw_interface_t * hi;
 225                   gre_tunnel_t * t;
 226                   uword * p;
 227
 228                   ip4_main_t * ip4m = &ip4_main;
 229                   p = hash_get (gm->tunnel_by_key, key);
 230                   if (!p)
 231                     {
 232                       next1 = GRE_INPUT_NEXT_DROP;
 233                       b1->error = node->errors[GRE_ERROR_NO_SUCH_TUNNEL];
 234                       goto drop1;
 235                     }
 236                   t = pool_elt_at_index (gm->tunnels, p[0]);
 237                   hi = vnet_get_hw_interface (gm->vnet_main,
 238                             t->hw_if_index);
 239                   tunnel_sw_if_index = hi->sw_if_index;
 240                   tunnel_fib_index = vec_elt (ip4m->fib_index_by_sw_if_index,
 241                                               tunnel_sw_if_index);
 242
 243                   cached_tunnel_sw_if_index = tunnel_sw_if_index;
 244                   cached_tunnel_fib_index = tunnel_fib_index;
 245                 }
 246               else
 247                 {
 248                   tunnel_sw_if_index = cached_tunnel_sw_if_index;
 249                   tunnel_fib_index = cached_tunnel_fib_index;
 250                 }
 251
 252               u32 len = vlib_buffer_length_in_chain (vm, b1);
 253               vnet_interface_main_t *im = &gm->vnet_main->interface_main;
 254               vlib_increment_combined_counter (im->combined_sw_if_counters
 255                                                + VNET_INTERFACE_COUNTER_RX,
 256                                                cpu_index,
 257                                                tunnel_sw_if_index,
 258                                                1 /* packets */,
 259                                                len /* bytes */);
 260
 261               vnet_buffer(b1)->sw_if_index[VLIB_TX] = tunnel_fib_index;
 262             }
 263 drop1:
 264           if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED))
 265             {
 266               gre_rx_trace_t *tr = vlib_add_trace (vm, node,
 267                                                    b0, sizeof (*tr));
 268               tr->tunnel_id = ~0;
 269               tr->length = ip0->length;
 270               tr->src.as_u32 = ip0->src_address.as_u32;
 271               tr->dst.as_u32 = ip0->dst_address.as_u32;
 272             }
 273
 274           if (PREDICT_FALSE(b1->flags & VLIB_BUFFER_IS_TRACED))
 275             {
 276               gre_rx_trace_t *tr = vlib_add_trace (vm, node,
 277                                                    b1, sizeof (*tr));
 278               tr->tunnel_id = ~0;
 279               tr->length = ip1->length;
 280               tr->src.as_u32 = ip1->src_address.as_u32;
 281               tr->dst.as_u32 = ip1->dst_address.as_u32;
 282             }
 283
 284           vlib_buffer_advance (b0, sizeof (*h0));
 285           vlib_buffer_advance (b1, sizeof (*h1));
 286
 287           vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
 288                                            to_next, n_left_to_next,
 289                                            bi0, bi1, next0, next1);
 290         }
 291
 292       while (n_left_from > 0 && n_left_to_next > 0)
 293         {
 294           u32 bi0;
 295           vlib_buffer_t * b0;
 296           gre_header_t * h0;
 297           ip4_header_t * ip0;
 298           u16 version0;
 299           int verr0;
 300           u32 i0, next0;
 301
 302           bi0 = from[0];
 303           to_next[0] = bi0;
 304           from += 1;
 305           to_next += 1;
 306           n_left_from -= 1;
 307           n_left_to_next -= 1;
 308
 309           b0 = vlib_get_buffer (vm, bi0);
 310           ip0 = vlib_buffer_get_current (b0);
 311
 312           vnet_buffer(b0)->gre.src = ip0->src_address.as_u32;
 313           vnet_buffer(b0)->gre.dst = ip0->dst_address.as_u32;
 314
 315           vlib_buffer_advance (b0, sizeof (*ip0));
 316
 317           h0 = vlib_buffer_get_current (b0);
 318
 319           i0 = sparse_vec_index (rt->next_by_protocol, h0->protocol);
 320           next0 = vec_elt(rt->next_by_protocol, i0);
 321
 322           b0->error =
 323               node->errors[next0 == SPARSE_VEC_INVALID_INDEX
 324                            ? GRE_ERROR_UNKNOWN_PROTOCOL : GRE_ERROR_NONE];
 325
 326           version0 = clib_net_to_host_u16 (h0->flags_and_version);
 327           verr0 =  version0 & GRE_VERSION_MASK;
 328           b0->error = verr0 ? node->errors[GRE_ERROR_UNSUPPORTED_VERSION]
 329               : b0->error;
 330           next0 = verr0 ? GRE_INPUT_NEXT_DROP : next0;
 331
 332           /* For IP payload we need to find source interface
 333              so we can increase counters and help forward node to
 334              pick right FIB */
 335           if (PREDICT_FALSE(next0 == GRE_INPUT_NEXT_IP4_INPUT
 336                             || next0 == GRE_INPUT_NEXT_IP6_INPUT))
 337             {
 338               u64 key = ((u64)(vnet_buffer(b0)->gre.dst) << 32) |
 339                          (u64)(vnet_buffer(b0)->gre.src);
 340
 341               if (cached_tunnel_key != key)
 342                 {
 343                   vnet_hw_interface_t * hi;
 344                   gre_tunnel_t * t;
 345                   uword * p;
 346
 347                   ip4_main_t * ip4m = &ip4_main;
 348                   p = hash_get (gm->tunnel_by_key, key);
 349                   if (!p)
 350                     {
 351                       next0 = GRE_INPUT_NEXT_DROP;
 352                       b0->error = node->errors[GRE_ERROR_NO_SUCH_TUNNEL];
 353                       goto drop;
 354                     }
 355                   t = pool_elt_at_index (gm->tunnels, p[0]);
 356                   hi = vnet_get_hw_interface (gm->vnet_main,
 357                             t->hw_if_index);
 358                   tunnel_sw_if_index = hi->sw_if_index;
 359                   tunnel_fib_index = vec_elt (ip4m->fib_index_by_sw_if_index,
 360                                               tunnel_sw_if_index);
 361
 362                   cached_tunnel_sw_if_index = tunnel_sw_if_index;
 363                   cached_tunnel_fib_index = tunnel_fib_index;
 364                 }
 365               else
 366                 {
 367                   tunnel_sw_if_index = cached_tunnel_sw_if_index;
 368                   tunnel_fib_index = cached_tunnel_fib_index;
 369                 }
 370
 371               u32 len = vlib_buffer_length_in_chain (vm, b0);
 372               vnet_interface_main_t *im = &gm->vnet_main->interface_main;
 373               vlib_increment_combined_counter (im->combined_sw_if_counters
 374                                                + VNET_INTERFACE_COUNTER_RX,
 375                                                cpu_index,
 376                                                tunnel_sw_if_index,
 377                                                1 /* packets */,
 378                                                len /* bytes */);
 379
 380               vnet_buffer(b0)->sw_if_index[VLIB_TX] = tunnel_fib_index;
 381             }
 382
 383 drop:
 384           if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED))
 385             {
 386               gre_rx_trace_t *tr = vlib_add_trace (vm, node,
 387                                                    b0, sizeof (*tr));
 388               tr->tunnel_id = ~0;
 389               tr->length = ip0->length;
 390               tr->src.as_u32 = ip0->src_address.as_u32;
 391               tr->dst.as_u32 = ip0->dst_address.as_u32;
 392             }
 393
 394           vlib_buffer_advance (b0, sizeof (*h0));
 395
 396           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 397                                            to_next, n_left_to_next,
 398                                            bi0, next0);
 399         }
 400
 401       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 402     }
 403   vlib_node_increment_counter (vm, gre_input_node.index,
 404                                GRE_ERROR_PKTS_DECAP, from_frame->n_vectors);
 405   return from_frame->n_vectors;
 406 }
 407
 408 static char * gre_error_strings[] = {
 409 #define gre_error(n,s) s,
 410 #include "error.def"
 411 #undef gre_error
 412 };
 413
 414 VLIB_REGISTER_NODE (gre_input_node) = {
 415   .function = gre_input,
 416   .name = "gre-input",
 417   /* Takes a vector of packets. */
 418   .vector_size = sizeof (u32),
 419
 420   .runtime_data_bytes = sizeof (gre_input_runtime_t),
 421
 422   .n_errors = GRE_N_ERROR,
 423   .error_strings = gre_error_strings,
 424
 425   .n_next_nodes = GRE_INPUT_N_NEXT,
 426   .next_nodes = {
 427 #define _(s,n) [GRE_INPUT_NEXT_##s] = n,
 428     foreach_gre_input_next
 429 #undef _
 430   },
 431
 432   .format_buffer = format_gre_header_with_length,
 433   .format_trace = format_gre_rx_trace,
 434   .unformat_buffer = unformat_gre_header,
 435 };
 436
 437 void
 438 gre_register_input_protocol (vlib_main_t * vm,
 439                              gre_protocol_t protocol,
 440                              u32 node_index)
 441 {
 442   gre_main_t * em = &gre_main;
 443   gre_protocol_info_t * pi;
 444   gre_input_runtime_t * rt;
 445   u16 * n;
 446   u32 i;
 447
 448   {
 449     clib_error_t * error = vlib_call_init_function (vm, gre_input_init);
 450     if (error)
 451       clib_error_report (error);
 452   }
 453
 454   pi = gre_get_protocol_info (em, protocol);
 455   pi->node_index = node_index;
 456   pi->next_index = vlib_node_add_next (vm,
 457                                        gre_input_node.index,
 458                                        node_index);
 459
 460   /* Setup gre protocol -> next index sparse vector mapping. */
 461   rt = vlib_node_get_runtime_data (vm, gre_input_node.index);
 462   n = sparse_vec_validate (rt->next_by_protocol,
 463                            clib_host_to_net_u16 (protocol));
 464   n[0] = pi->next_index;
 465
 466   /* Rebuild next index -> sparse index inverse mapping when sparse vector
 467      is updated. */
 468   vec_validate (rt->sparse_index_by_next_index, pi->next_index);
 469   for (i = 1; i < vec_len (rt->next_by_protocol); i++)
 470     rt->sparse_index_by_next_index[rt->next_by_protocol[i]] = i;
 471 }
 472
 473 static void
 474 gre_setup_node (vlib_main_t * vm, u32 node_index)
 475 {
 476   vlib_node_t * n = vlib_get_node (vm, node_index);
 477   pg_node_t * pn = pg_get_node (node_index);
 478
 479   n->format_buffer = format_gre_header_with_length;
 480   n->unformat_buffer = unformat_gre_header;
 481   pn->unformat_edit = unformat_pg_gre_header;
 482 }
 483
 484 static clib_error_t * gre_input_init (vlib_main_t * vm)
 485 {
 486   gre_input_runtime_t * rt;
 487   vlib_node_t *ip4_input, *ip6_input, *mpls_unicast_input;
 488
 489   {
 490     clib_error_t * error;
 491     error = vlib_call_init_function (vm, gre_init);
 492     if (error)
 493       clib_error_report (error);
 494   }
 495
 496   gre_setup_node (vm, gre_input_node.index);
 497
 498   rt = vlib_node_get_runtime_data (vm, gre_input_node.index);
 499
 500   rt->next_by_protocol = sparse_vec_new
 501     (/* elt bytes */ sizeof (rt->next_by_protocol[0]),
 502      /* bits in index */ BITS (((gre_header_t *) 0)->protocol));
 503
 504   vec_validate (rt->sparse_index_by_next_index, GRE_INPUT_NEXT_DROP);
 505   vec_validate (rt->sparse_index_by_next_index, GRE_INPUT_NEXT_PUNT);
 506   rt->sparse_index_by_next_index[GRE_INPUT_NEXT_DROP]
 507     = SPARSE_VEC_INVALID_INDEX;
 508   rt->sparse_index_by_next_index[GRE_INPUT_NEXT_PUNT]
 509     = SPARSE_VEC_INVALID_INDEX;
 510
 511   /* These could be moved to the supported protocol input node defn's */
 512   ip4_input = vlib_get_node_by_name (vm, (u8 *)"ip4-input");
 513   ASSERT(ip4_input);
 514   ip6_input = vlib_get_node_by_name (vm, (u8 *)"ip6-input");
 515   ASSERT(ip6_input);
 516   mpls_unicast_input = vlib_get_node_by_name (vm, (u8 *)"mpls-gre-input");
 517   ASSERT(mpls_unicast_input);
 518
 519   gre_register_input_protocol (vm, GRE_PROTOCOL_ip4,
 520                                ip4_input->index);
 521
 522   gre_register_input_protocol (vm, GRE_PROTOCOL_ip6,
 523                                ip6_input->index);
 524
 525   gre_register_input_protocol (vm, GRE_PROTOCOL_mpls_unicast,
 526                                mpls_unicast_input->index);
 527
 528   ip4_register_protocol (IP_PROTOCOL_GRE, gre_input_node.index);
 529
 530   return 0;
 531 }
 532
 533 VLIB_INIT_FUNCTION (gre_input_init);