vnet/vnet/ip/ip4.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.h: ip4 main include file
  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_ip_ip4_h
  41 #define included_ip_ip4_h
  42
  43 #include <vnet/ip/ip4_mtrie.h>
  44 #include <vnet/ip/ip4_packet.h>
  45 #include <vnet/ip/lookup.h>
  46 #include <vnet/ip/ip_feature_registration.h>
  47
  48 typedef struct ip4_fib_t {
  49   /* Hash table for each prefix length mapping. */
  50   uword * adj_index_by_dst_address[33];
  51
  52   /* Temporary vectors for holding new/old values for hash_set. */
  53   uword * new_hash_values, * old_hash_values;
  54
  55   /* Mtrie for fast lookups.  Hash is used to maintain overlapping prefixes. */
  56   ip4_fib_mtrie_t mtrie;
  57
  58   /* Table ID (hash key) for this FIB. */
  59   u32 table_id;
  60
  61   /* Index into FIB vector. */
  62   u32 index;
  63
  64   /* flow hash configuration */
  65   u32 flow_hash_config;
  66
  67   /* N-tuple classifier indices */
  68   u32 fwd_classify_table_index;
  69   u32 rev_classify_table_index;
  70
  71 } ip4_fib_t;
  72
  73 struct ip4_main_t;
  74
  75 typedef void (ip4_add_del_route_function_t)
  76   (struct ip4_main_t * im,
  77    uword opaque,
  78    ip4_fib_t * fib,
  79    u32 flags,
  80    ip4_address_t * address,
  81    u32 address_length,
  82    void * old_result,
  83    void * new_result);
  84
  85 typedef struct {
  86   ip4_add_del_route_function_t * function;
  87   uword required_flags;
  88   uword function_opaque;
  89 } ip4_add_del_route_callback_t;
  90
  91 typedef void (ip4_add_del_interface_address_function_t)
  92   (struct ip4_main_t * im,
  93    uword opaque,
  94    u32 sw_if_index,
  95    ip4_address_t * address,
  96    u32 address_length,
  97    u32 if_address_index,
  98    u32 is_del);
  99
 100 typedef struct {
 101   ip4_add_del_interface_address_function_t * function;
 102   uword function_opaque;
 103 } ip4_add_del_interface_address_callback_t;
 104
 105 typedef struct ip4_main_t {
 106   ip_lookup_main_t lookup_main;
 107
 108   /* Vector of FIBs. */
 109   ip4_fib_t * fibs;
 110
 111   u32 fib_masks[33];
 112
 113   /* Table index indexed by software interface. */
 114   u32 * fib_index_by_sw_if_index;
 115
 116   /* Hash table mapping table id to fib index.
 117      ID space is not necessarily dense; index space is dense. */
 118   uword * fib_index_by_table_id;
 119
 120   /* Vector of functions to call when routes are added/deleted. */
 121   ip4_add_del_route_callback_t * add_del_route_callbacks;
 122
 123   /* Hash table mapping interface route rewrite adjacency index by sw if index. */
 124   uword * interface_route_adj_index_by_sw_if_index;
 125
 126   /* Functions to call when interface address changes. */
 127   ip4_add_del_interface_address_callback_t * add_del_interface_address_callbacks;
 128
 129   /* Template used to generate IP4 ARP packets. */
 130   vlib_packet_template_t ip4_arp_request_packet_template;
 131
 132   /* feature path configuration lists */
 133   vnet_ip_feature_registration_t * next_uc_feature;
 134   vnet_ip_feature_registration_t * next_mc_feature;
 135
 136   /* Built-in unicast feature path indices, see ip_feature_init_cast(...)  */
 137   u32 ip4_unicast_rx_feature_check_access;
 138   u32 ip4_unicast_rx_feature_source_reachable_via_rx;
 139   u32 ip4_unicast_rx_feature_source_reachable_via_any;
 140   u32 ip4_unicast_rx_feature_ipsec;
 141   u32 ip4_unicast_rx_feature_vpath;
 142   u32 ip4_unicast_rx_feature_lookup;
 143
 144   /* Built-in multicast feature path indices */
 145   u32 ip4_multicast_rx_feature_vpath;
 146   u32 ip4_multicast_rx_feature_lookup;
 147
 148   /* Seed for Jenkins hash used to compute ip4 flow hash. */
 149   u32 flow_hash_seed;
 150
 151   struct {
 152     /* TTL to use for host generated packets. */
 153     u8 ttl;
 154
 155     /* TOS byte to use for host generated packets. */
 156     u8 tos;
 157
 158     u8 pad[2];
 159   } host_config;
 160 } ip4_main_t;
 161
 162 /* Global ip4 main structure. */
 163 extern ip4_main_t ip4_main;
 164
 165 #define VNET_IP4_UNICAST_FEATURE_INIT(x,...)                    \
 166   __VA_ARGS__ vnet_ip_feature_registration_t uc_##x;            \
 167 static void __vnet_add_feature_registration_uc_##x (void)       \
 168   __attribute__((__constructor__)) ;                            \
 169 static void __vnet_add_feature_registration_uc_##x (void)       \
 170 {                                                               \
 171   ip4_main_t * im = &ip4_main;                                  \
 172   uc_##x.next = im->next_uc_feature;                            \
 173   im->next_uc_feature = &uc_##x;                                \
 174 }                                                               \
 175 __VA_ARGS__ vnet_ip_feature_registration_t uc_##x
 176
 177 #define VNET_IP4_MULTICAST_FEATURE_INIT(x,...)                  \
 178   __VA_ARGS__ vnet_ip_feature_registration_t mc_##x;            \
 179 static void __vnet_add_feature_registration_mc_##x (void)       \
 180   __attribute__((__constructor__)) ;                            \
 181 static void __vnet_add_feature_registration_mc_##x (void)       \
 182 {                                                               \
 183   ip4_main_t * im = &ip4_main;                                  \
 184   mc_##x.next = im->next_mc_feature;                            \
 185   im->next_mc_feature = &mc_##x;                                \
 186 }                                                               \
 187 __VA_ARGS__ vnet_ip_feature_registration_t mc_##x
 188
 189
 190 /* Global ip4 input node.  Errors get attached to ip4 input node. */
 191 extern vlib_node_registration_t ip4_input_node;
 192 extern vlib_node_registration_t ip4_lookup_node;
 193 extern vlib_node_registration_t ip4_rewrite_node;
 194 extern vlib_node_registration_t ip4_rewrite_local_node;
 195 extern vlib_node_registration_t ip4_arp_node;
 196
 197 u32 ip4_fib_lookup_with_table (ip4_main_t * im, u32 fib_index, ip4_address_t * dst,
 198                                u32 disable_default_route);
 199
 200 always_inline u32
 201 ip4_fib_lookup_buffer (ip4_main_t * im, u32 fib_index, ip4_address_t * dst,
 202                        vlib_buffer_t * b)
 203 {
 204   return ip4_fib_lookup_with_table (im, fib_index, dst,
 205                                     /* disable_default_route */ 0);
 206 }
 207
 208 always_inline u32
 209 ip4_fib_lookup (ip4_main_t * im, u32 sw_if_index, ip4_address_t * dst)
 210 {
 211   u32 fib_index = vec_elt (im->fib_index_by_sw_if_index, sw_if_index);
 212   return ip4_fib_lookup_with_table (im, fib_index, dst,
 213                                     /* disable_default_route */ 0);
 214 }
 215
 216 always_inline uword
 217 ip4_destination_matches_route (ip4_main_t * im,
 218                                ip4_address_t * key,
 219                                ip4_address_t * dest,
 220                                uword dest_length)
 221 { return 0 == ((key->data_u32 ^ dest->data_u32) & im->fib_masks[dest_length]); }
 222
 223 always_inline uword
 224 ip4_destination_matches_interface (ip4_main_t * im,
 225                                    ip4_address_t * key,
 226                                    ip_interface_address_t * ia)
 227 {
 228   ip4_address_t * a = ip_interface_address_get_address (&im->lookup_main, ia);
 229   return ip4_destination_matches_route (im, key, a, ia->address_length);
 230 }
 231
 232 /* As above but allows for unaligned destinations (e.g. works right from IP header of packet). */
 233 always_inline uword
 234 ip4_unaligned_destination_matches_route (ip4_main_t * im,
 235                                          ip4_address_t * key,
 236                                          ip4_address_t * dest,
 237                                          uword dest_length)
 238 { return 0 == ((clib_mem_unaligned (&key->data_u32, u32) ^ dest->data_u32) & im->fib_masks[dest_length]); }
 239
 240 always_inline void
 241 ip4_src_address_for_packet (ip4_main_t * im, vlib_buffer_t * p, ip4_address_t * src, u32 sw_if_index)
 242 {
 243   ip_lookup_main_t * lm = &im->lookup_main;
 244   ip_interface_address_t * ia = ip_interface_address_for_packet (lm, p, sw_if_index);
 245   ip4_address_t * a = ip_interface_address_get_address (lm, ia);
 246   *src = a[0];
 247 }
 248
 249 /* Find interface address which matches destination. */
 250 always_inline ip4_address_t *
 251 ip4_interface_address_matching_destination (ip4_main_t * im, ip4_address_t * dst, u32 sw_if_index,
 252                                             ip_interface_address_t ** result_ia)
 253 {
 254   ip_lookup_main_t * lm = &im->lookup_main;
 255   ip_interface_address_t * ia;
 256   ip4_address_t * result = 0;
 257
 258   foreach_ip_interface_address (lm, ia, sw_if_index,
 259                                 1 /* honor unnumbered */,
 260   ({
 261     ip4_address_t * a = ip_interface_address_get_address (lm, ia);
 262     if (ip4_destination_matches_route (im, dst, a, ia->address_length))
 263       {
 264         result = a;
 265         break;
 266       }
 267   }));
 268   if (result_ia)
 269     *result_ia = result ? ia : 0;
 270   return result;
 271 }
 272
 273 clib_error_t *
 274 ip4_add_del_interface_address (vlib_main_t * vm, u32 sw_if_index,
 275                                ip4_address_t * address, u32 address_length,
 276                                u32 is_del);
 277
 278 int ip4_address_compare (ip4_address_t * a1, ip4_address_t * a2);
 279
 280 /* Add/del a route to the FIB. */
 281
 282 #define IP4_ROUTE_FLAG_ADD (0 << 0)
 283 #define IP4_ROUTE_FLAG_DEL (1 << 0)
 284 #define IP4_ROUTE_FLAG_TABLE_ID  (0 << 1)
 285 #define IP4_ROUTE_FLAG_FIB_INDEX (1 << 1)
 286 #define IP4_ROUTE_FLAG_KEEP_OLD_ADJACENCY (1 << 2)
 287 #define IP4_ROUTE_FLAG_NO_REDISTRIBUTE (1 << 3)
 288 /* Not last add/del in group.  Facilities batching requests into packets. */
 289 #define IP4_ROUTE_FLAG_NOT_LAST_IN_GROUP (1 << 4)
 290 /* Dynamic route created via ARP reply. */
 291 #define IP4_ROUTE_FLAG_NEIGHBOR (1 << 5)
 292
 293 typedef struct {
 294   /* IP4_ROUTE_FLAG_* */
 295   u32 flags;
 296
 297   /* Either index of fib or table_id to hash and get fib.
 298      IP4_ROUTE_FLAG_FIB_INDEX specifies index; otherwise table_id is assumed. */
 299   u32 table_index_or_table_id;
 300
 301   /* Destination address (prefix) and length. */
 302   ip4_address_t dst_address;
 303   u32 dst_address_length;
 304
 305   /* Adjacency to use for this destination. */
 306   u32 adj_index;
 307
 308   /* If specified adjacencies to add and then
 309      use for this destination.  add_adj/n_add_adj
 310      are override adj_index if specified. */
 311   ip_adjacency_t * add_adj;
 312   u32 n_add_adj;
 313 } ip4_add_del_route_args_t;
 314
 315 /**
 316  * \brief Get or create an IPv4 fib.
 317  *
 318  * Get or create an IPv4 fib with the provided fib ID or index.
 319  * The fib ID is a possibly-sparse user-defined value while
 320  * the fib index defines the position of the fib in the fib vector.
 321  *
 322  * \param im
 323  *      ip4_main pointer.
 324  * \param table_index_or_id
 325  *      The table index if \c IP4_ROUTE_FLAG_FIB_INDEX bit is set in \p flags.
 326  *      Otherwise, when set to \c ~0, an arbitrary and unused fib ID is picked
 327  *      and can be retrieved with \c ret->table_id.
 328  *      Otherwise, the fib ID to be used to retrieve or create the desired fib.
 329  * \param flags
 330  *      Indicates whether \p table_index_or_id is the fib index or ID.
 331  *      When the bit \c IP4_ROUTE_FLAG_FIB_INDEX is set, \p table_index_or_id
 332  *      is considered as the fib index, and the fib ID otherwise.
 333  * \returns A pointer to the retrieved or created fib.
 334  *
 335  * \remark When getting a fib with the fib index, the fib MUST already exist.
 336  */
 337 ip4_fib_t *
 338 find_ip4_fib_by_table_index_or_id (ip4_main_t * im,
 339                                    u32 table_index_or_id, u32 flags);
 340
 341 void ip4_add_del_route (ip4_main_t * im, ip4_add_del_route_args_t * args);
 342
 343 void ip4_add_del_route_next_hop (ip4_main_t * im,
 344                                  u32 flags,
 345                                  ip4_address_t * dst_address,
 346                                  u32 dst_address_length,
 347                                  ip4_address_t * next_hop,
 348                                  u32 next_hop_sw_if_index,
 349                                  u32 next_hop_weight, u32 adj_index,
 350                                  u32 explicit_fib_index);
 351
 352 void *
 353 ip4_get_route (ip4_main_t * im,
 354                u32 fib_index_or_table_id,
 355                u32 flags,
 356                u8 * address,
 357                u32 address_length);
 358
 359 void
 360 ip4_foreach_matching_route (ip4_main_t * im,
 361                             u32 table_index_or_table_id,
 362                             u32 flags,
 363                             ip4_address_t * address,
 364                             u32 address_length,
 365                             ip4_address_t ** results,
 366                             u8 ** result_lengths);
 367
 368 void ip4_delete_matching_routes (ip4_main_t * im,
 369                                  u32 table_index_or_table_id,
 370                                  u32 flags,
 371                                  ip4_address_t * address,
 372                                  u32 address_length);
 373
 374 void ip4_maybe_remap_adjacencies (ip4_main_t * im,
 375                                   u32 table_index_or_table_id,
 376                                   u32 flags);
 377
 378 void ip4_adjacency_set_interface_route (vnet_main_t * vnm,
 379                                         ip_adjacency_t * adj,
 380                                         u32 sw_if_index,
 381                                         u32 if_address_index);
 382
 383 /* Send an ARP request to see if given destination is reachable on given interface. */
 384 clib_error_t *
 385 ip4_probe_neighbor (vlib_main_t * vm, ip4_address_t * dst, u32 sw_if_index);
 386
 387 clib_error_t *
 388 ip4_set_arp_limit (u32 arp_limit);
 389
 390 uword
 391 ip4_udp_register_listener (vlib_main_t * vm,
 392                            u16 dst_port,
 393                            u32 next_node_index);
 394
 395 void
 396 ip4_icmp_register_type (vlib_main_t * vm, icmp4_type_t type,
 397                         u32 node_index);
 398
 399 u16 ip4_tcp_udp_compute_checksum (vlib_main_t * vm, vlib_buffer_t * p0, ip4_header_t * ip0);
 400
 401 void ip4_register_protocol (u32 protocol, u32 node_index);
 402
 403 serialize_function_t serialize_vnet_ip4_main, unserialize_vnet_ip4_main;
 404
 405 int vnet_set_ip4_flow_hash (u32 table_id, u32 flow_hash_config);
 406
 407 void ip4_mtrie_init (ip4_fib_mtrie_t * m);
 408
 409 int vnet_set_ip4_classify_intfc (vlib_main_t * vm, u32 sw_if_index,
 410                                  u32 table_index);
 411
 412 /* Compute flow hash.  We'll use it to select which adjacency to use for this
 413    flow.  And other things. */
 414 always_inline u32
 415 ip4_compute_flow_hash (ip4_header_t * ip, u32 flow_hash_config)
 416 {
 417     tcp_header_t * tcp = (void *) (ip + 1);
 418     u32 a, b, c, t1, t2;
 419     uword is_tcp_udp = (ip->protocol == IP_PROTOCOL_TCP
 420                         || ip->protocol == IP_PROTOCOL_UDP);
 421
 422     t1 = (flow_hash_config & IP_FLOW_HASH_SRC_ADDR)
 423         ? ip->src_address.data_u32 : 0;
 424     t2 = (flow_hash_config & IP_FLOW_HASH_DST_ADDR)
 425         ? ip->dst_address.data_u32 : 0;
 426
 427     a = (flow_hash_config & IP_FLOW_HASH_REVERSE_SRC_DST) ? t2 : t1;
 428     b = (flow_hash_config & IP_FLOW_HASH_REVERSE_SRC_DST) ? t1 : t2;
 429     b ^= (flow_hash_config & IP_FLOW_HASH_PROTO) ? ip->protocol : 0;
 430
 431     t1 = is_tcp_udp ? tcp->ports.src : 0;
 432     t2 = is_tcp_udp ? tcp->ports.dst : 0;
 433
 434     t1 = (flow_hash_config & IP_FLOW_HASH_SRC_PORT) ? t1 : 0;
 435     t2 = (flow_hash_config & IP_FLOW_HASH_DST_PORT) ? t2 : 0;
 436
 437     c = (flow_hash_config & IP_FLOW_HASH_REVERSE_SRC_DST) ?
 438         (t1<<16) | t2 : (t2<<16) | t1;
 439
 440     hash_v3_mix32 (a, b, c);
 441     hash_v3_finalize32 (a, b, c);
 442
 443     return c;
 444 }
 445
 446 #endif /* included_ip_ip4_h */