vnet/vnet/ip/lookup.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/ip_lookup.h: ip (4 or 6) lookup structures, adjacencies, ...
  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 /**
  41  * @file
  42  * Definitions for all things IP (v4|v6) unicast and multicast lookup related.
  43  *
  44  * - Adjacency definitions and registration.
  45  * - Callbacks on route add.
  46  * - Callbacks on interface address change.
  47  */
  48 #ifndef included_ip_lookup_h
  49 #define included_ip_lookup_h
  50
  51 #include <vnet/vnet.h>
  52 #include <vlib/buffer.h>
  53 #include <vnet/ip/ip4_packet.h>
  54 #include <vnet/ip/ip6_packet.h>
  55 #include <vnet/fib/fib_node.h>
  56 #include <vnet/dpo/dpo.h>
  57 #include <vnet/ip/ip_feature_registration.h>
  58
  59 /** @brief Common (IP4/IP6) next index stored in adjacency. */
  60 typedef enum {
  61   /** Adjacency to drop this packet. */
  62   IP_LOOKUP_NEXT_DROP,
  63   /** Adjacency to punt this packet. */
  64   IP_LOOKUP_NEXT_PUNT,
  65
  66   /** This packet is for one of our own IP addresses. */
  67   IP_LOOKUP_NEXT_LOCAL,
  68
  69   /** This packet matches an "incomplete adjacency" and packets
  70      need to be passed to ARP to find rewrite string for
  71      this destination. */
  72   IP_LOOKUP_NEXT_ARP,
  73
  74   /** This packet matches an "interface route" and packets
  75      need to be passed to ARP to find rewrite string for
  76      this destination. */
  77   IP_LOOKUP_NEXT_GLEAN,
  78
  79   /** This packet is to be rewritten and forwarded to the next
  80      processing node.  This is typically the output interface but
  81      might be another node for further output processing. */
  82   IP_LOOKUP_NEXT_REWRITE,
  83
  84   /** This packets follow a load-balance */
  85   IP_LOOKUP_NEXT_LOAD_BALANCE,
  86
  87   /** This packets follow a mid-chain adjacency */
  88   IP_LOOKUP_NEXT_MIDCHAIN,
  89
  90   /** This packets needs to go to ICMP error */
  91   IP_LOOKUP_NEXT_ICMP_ERROR,
  92
  93   IP_LOOKUP_N_NEXT,
  94 } ip_lookup_next_t;
  95
  96 typedef enum {
  97   IP4_LOOKUP_N_NEXT = IP_LOOKUP_N_NEXT,
  98 } ip4_lookup_next_t;
  99
 100 typedef enum {
 101   /* Hop-by-hop header handling */
 102   IP6_LOOKUP_NEXT_HOP_BY_HOP = IP_LOOKUP_N_NEXT,
 103   IP6_LOOKUP_NEXT_ADD_HOP_BY_HOP,
 104   IP6_LOOKUP_NEXT_POP_HOP_BY_HOP,
 105   IP6_LOOKUP_N_NEXT,
 106 } ip6_lookup_next_t;
 107
 108 #define IP4_LOOKUP_NEXT_NODES {                                 \
 109     [IP_LOOKUP_NEXT_DROP] = "ip4-drop",                         \
 110     [IP_LOOKUP_NEXT_PUNT] = "ip4-punt",                         \
 111     [IP_LOOKUP_NEXT_LOCAL] = "ip4-local",                       \
 112     [IP_LOOKUP_NEXT_ARP] = "ip4-arp",                           \
 113     [IP_LOOKUP_NEXT_GLEAN] = "ip4-glean",                       \
 114     [IP_LOOKUP_NEXT_REWRITE] = "ip4-rewrite-transit",           \
 115     [IP_LOOKUP_NEXT_MIDCHAIN] = "ip4-midchain",                 \
 116     [IP_LOOKUP_NEXT_LOAD_BALANCE] = "ip4-load-balance",         \
 117     [IP_LOOKUP_NEXT_ICMP_ERROR] = "ip4-icmp-error",             \
 118 }
 119
 120 #define IP6_LOOKUP_NEXT_NODES {                                 \
 121     [IP_LOOKUP_NEXT_DROP] = "ip6-drop",                         \
 122     [IP_LOOKUP_NEXT_PUNT] = "ip6-punt",                         \
 123     [IP_LOOKUP_NEXT_LOCAL] = "ip6-local",                       \
 124     [IP_LOOKUP_NEXT_ARP] = "ip6-discover-neighbor",             \
 125     [IP_LOOKUP_NEXT_GLEAN] = "ip6-glean",                       \
 126     [IP_LOOKUP_NEXT_REWRITE] = "ip6-rewrite",                   \
 127     [IP_LOOKUP_NEXT_MIDCHAIN] = "ip6-midchain",                 \
 128     [IP_LOOKUP_NEXT_LOAD_BALANCE] = "ip6-load-balance",         \
 129     [IP_LOOKUP_NEXT_ICMP_ERROR] = "ip6-icmp-error",             \
 130     [IP6_LOOKUP_NEXT_HOP_BY_HOP] = "ip6-hop-by-hop",            \
 131     [IP6_LOOKUP_NEXT_ADD_HOP_BY_HOP] = "ip6-add-hop-by-hop",    \
 132     [IP6_LOOKUP_NEXT_POP_HOP_BY_HOP] = "ip6-pop-hop-by-hop",    \
 133 }
 134
 135 /** Flow hash configuration */
 136 #define IP_FLOW_HASH_SRC_ADDR (1<<0)
 137 #define IP_FLOW_HASH_DST_ADDR (1<<1)
 138 #define IP_FLOW_HASH_PROTO (1<<2)
 139 #define IP_FLOW_HASH_SRC_PORT (1<<3)
 140 #define IP_FLOW_HASH_DST_PORT (1<<4)
 141 #define IP_FLOW_HASH_REVERSE_SRC_DST (1<<5)
 142
 143 /** Default: 5-tuple without the "reverse" bit */
 144 #define IP_FLOW_HASH_DEFAULT (0x1F)
 145
 146 #define foreach_flow_hash_bit                   \
 147 _(src, IP_FLOW_HASH_SRC_ADDR)                   \
 148 _(dst, IP_FLOW_HASH_DST_ADDR)                   \
 149 _(sport, IP_FLOW_HASH_SRC_PORT)                 \
 150 _(dport, IP_FLOW_HASH_DST_PORT)                 \
 151 _(proto, IP_FLOW_HASH_PROTO)                    \
 152 _(reverse, IP_FLOW_HASH_REVERSE_SRC_DST)
 153
 154 /**
 155  * A flow hash configuration is a mask of the flow hash options
 156  */
 157 typedef u32 flow_hash_config_t;
 158
 159 /**
 160  * Forward delcartion
 161  */
 162 struct ip_adjacency_t_;
 163
 164 /**
 165  * @brief A function type for post-rewrite fixups on midchain adjacency
 166  */
 167 typedef void (*adj_midchain_fixup_t)(vlib_main_t * vm,
 168                                      struct ip_adjacency_t_ *adj,
 169                                      vlib_buffer_t * b0);
 170
 171 /** @brief IP unicast adjacency.
 172     @note cache aligned.
 173 */
 174 typedef struct ip_adjacency_t_ {
 175   CLIB_CACHE_LINE_ALIGN_MARK(cacheline0);
 176
 177   /** Number of adjecencies in block.  Greater than 1 means multipath;
 178      otherwise equal to 1. */
 179   u16 n_adj;
 180
 181   /** Next hop after ip4-lookup. */
 182   union {
 183     ip_lookup_next_t lookup_next_index : 16;
 184     u16 lookup_next_index_as_int;
 185   };
 186
 187   /** Interface address index for this local/arp adjacency. */
 188   u32 if_address_index;
 189
 190   /** Force re-lookup in a different FIB. ~0 => normal behavior */
 191   u16 mcast_group_index;
 192
 193   /** Highest possible perf subgraph arc interposition, e.g. for ip6 ioam */
 194   u16 saved_lookup_next_index;
 195
 196   /*
 197    * link/ether-type
 198    */
 199   u8 ia_link;
 200   u8 ia_nh_proto;
 201
 202   union {
 203     union {
 204         /**
 205          * IP_LOOKUP_NEXT_ARP/IP_LOOKUP_NEXT_REWRITE
 206          *
 207          * neighbour adjacency sub-type;
 208          */
 209         struct {
 210             ip46_address_t next_hop;
 211         } nbr;
 212         /**
 213          * IP_LOOKUP_NEXT_MIDCHAIN
 214          *
 215          * A nbr adj that is also recursive. Think tunnels.
 216          * A nbr adj can transition to be of type MDICHAIN
 217          * so be sure to leave the two structs with the next_hop
 218          * fields aligned.
 219          */
 220         struct {
 221             /**
 222              * The recursive next-hop
 223              */
 224             ip46_address_t next_hop;
 225             /**
 226              * The node index of the tunnel's post rewrite/TX function.
 227              */
 228             u32 tx_function_node;
 229             /**
 230              * The next DPO to use
 231              */
 232             dpo_id_t next_dpo;
 233
 234             /**
 235              * A function to perform the post-rewrite fixup
 236              */
 237             adj_midchain_fixup_t fixup_func;
 238         } midchain;
 239         /**
 240          * IP_LOOKUP_NEXT_GLEAN
 241          *
 242          * Glean the address to ARP for from the packet's destination
 243          */
 244         struct {
 245             ip46_address_t receive_addr;
 246         } glean;
 247     } sub_type;
 248   };
 249
 250   CLIB_CACHE_LINE_ALIGN_MARK(cacheline1);
 251
 252   /* Rewrite in second/third cache lines */
 253   vnet_declare_rewrite (VLIB_BUFFER_PRE_DATA_SIZE);
 254
 255   /*
 256    * member not accessed in the data plane are relgated to the
 257    * remaining cachelines
 258    */
 259   fib_node_t ia_node;
 260 } ip_adjacency_t;
 261
 262 _Static_assert((STRUCT_OFFSET_OF(ip_adjacency_t, cacheline0) == 0),
 263                "IP adjacency cachline 0 is not offset");
 264 _Static_assert((STRUCT_OFFSET_OF(ip_adjacency_t, cacheline1) ==
 265                 CLIB_CACHE_LINE_BYTES),
 266                "IP adjacency cachline 1 is more than one cachline size offset");
 267
 268 /* An all zeros address */
 269 extern const ip46_address_t zero_addr;
 270
 271 /* IP multicast adjacency. */
 272 typedef struct {
 273   /* Handle for this adjacency in adjacency heap. */
 274   u32 heap_handle;
 275
 276   /* Number of adjecencies in block. */
 277   u32 n_adj;
 278
 279   /* Rewrite string. */
 280   vnet_declare_rewrite (64 - 2*sizeof(u32));
 281 } ip_multicast_rewrite_t;
 282
 283 typedef struct {
 284   /* ip4-multicast-rewrite next index. */
 285   u32 next_index;
 286
 287   u8 n_rewrite_bytes;
 288
 289   u8 rewrite_string[64 - 1*sizeof(u32) - 1*sizeof(u8)];
 290 } ip_multicast_rewrite_string_t;
 291
 292 typedef struct {
 293   ip_multicast_rewrite_t * rewrite_heap;
 294
 295   ip_multicast_rewrite_string_t * rewrite_strings;
 296
 297   /* Negative rewrite string index; >= 0 sw_if_index.
 298      Sorted.  Used to hash. */
 299   i32 ** adjacency_id_vector;
 300
 301   uword * adjacency_by_id_vector;
 302 } ip_multicast_lookup_main_t;
 303
 304 typedef struct {
 305   /* Key for mhash; in fact, just a byte offset into mhash key vector. */
 306   u32 address_key;
 307
 308   /* Interface which has this address. */
 309   u32 sw_if_index;
 310
 311   /* Adjacency for neighbor probe (ARP) for this interface address. */
 312   u32 neighbor_probe_adj_index;
 313
 314   /* Address (prefix) length for this interface. */
 315   u16 address_length;
 316
 317   /* Will be used for something eventually.  Primary vs. secondary? */
 318   u16 flags;
 319
 320   /* Next and previous pointers for doubly linked list of
 321      addresses per software interface. */
 322   u32 next_this_sw_interface;
 323   u32 prev_this_sw_interface;
 324 } ip_interface_address_t;
 325
 326 typedef enum {
 327   IP_LOCAL_NEXT_DROP,
 328   IP_LOCAL_NEXT_PUNT,
 329   IP_LOCAL_NEXT_UDP_LOOKUP,
 330   IP_LOCAL_NEXT_ICMP,
 331   IP_LOCAL_N_NEXT,
 332 } ip_local_next_t;
 333
 334 struct ip_lookup_main_t;
 335
 336 typedef void (* ip_add_del_adjacency_callback_t) (struct ip_lookup_main_t * lm,
 337                                                   u32 adj_index,
 338                                                   ip_adjacency_t * adj,
 339                                                   u32 is_del);
 340
 341 typedef struct ip_lookup_main_t {
 342   /* Adjacency heap. */
 343   ip_adjacency_t * adjacency_heap;
 344
 345   /** load-balance  packet/byte counters indexed by LB index. */
 346   vlib_combined_counter_main_t load_balance_counters;
 347
 348   /** any-tx-feature-enabled interface bitmap */
 349   uword * tx_sw_if_has_ip_output_features;
 350
 351   /** count of enabled features, per sw_if_index, to maintain bitmap */
 352   i16 * tx_feature_count_by_sw_if_index;
 353
 354   /** Pool of addresses that are assigned to interfaces. */
 355   ip_interface_address_t * if_address_pool;
 356
 357   /** Hash table mapping address to index in interface address pool. */
 358   mhash_t address_to_if_address_index;
 359
 360   /** Head of doubly linked list of interface addresses for each software interface.
 361      ~0 means this interface has no address. */
 362   u32 * if_address_pool_index_by_sw_if_index;
 363
 364   /** First table index to use for this interface, ~0 => none */
 365   u32 * classify_table_index_by_sw_if_index;
 366
 367   /** rx unicast, multicast, tx interface/feature configuration. */
 368   ip_config_main_t feature_config_mains[VNET_N_IP_FEAT];
 369
 370   /** Number of bytes in a fib result.  Must be at least
 371      sizeof (uword).  First word is always adjacency index. */
 372   u32 fib_result_n_bytes, fib_result_n_words;
 373
 374   format_function_t * format_fib_result;
 375
 376   /** 1 for ip6; 0 for ip4. */
 377   u32 is_ip6;
 378
 379   /** Either format_ip4_address_and_length or format_ip6_address_and_length. */
 380   format_function_t * format_address_and_length;
 381
 382   /** Special adjacency format functions */
 383   format_function_t ** special_adjacency_format_functions;
 384
 385   /** Table mapping ip protocol to ip[46]-local node next index. */
 386   u8 local_next_by_ip_protocol[256];
 387
 388   /** IP_BUILTIN_PROTOCOL_{TCP,UDP,ICMP,OTHER} by protocol in IP header. */
 389   u8 builtin_protocol_by_ip_protocol[256];
 390 } ip_lookup_main_t;
 391
 392 always_inline ip_adjacency_t *
 393 ip_get_adjacency (ip_lookup_main_t * lm,
 394                   u32 adj_index)
 395 {
 396   ip_adjacency_t * adj;
 397
 398   adj = vec_elt_at_index (lm->adjacency_heap, adj_index);
 399
 400   return adj;
 401 }
 402
 403 #define ip_prefetch_adjacency(lm,adj_index,type)                \
 404 do {                                                            \
 405   ip_adjacency_t * _adj = (lm)->adjacency_heap + (adj_index);   \
 406   CLIB_PREFETCH (_adj, sizeof (_adj[0]), type);                 \
 407 } while (0)
 408
 409 /* Create new block of given number of contiguous adjacencies. */
 410 ip_adjacency_t *
 411 ip_add_adjacency (ip_lookup_main_t * lm,
 412                   ip_adjacency_t * adj,
 413                   u32 n_adj,
 414                   u32 * adj_index_result);
 415
 416 clib_error_t *
 417 ip_interface_address_add_del (ip_lookup_main_t * lm,
 418                               u32 sw_if_index,
 419                               void * address,
 420                               u32 address_length,
 421                               u32 is_del,
 422                               u32 * result_index);
 423
 424 u8 *
 425 format_ip_flow_hash_config (u8 * s, va_list * args);
 426
 427 always_inline ip_interface_address_t *
 428 ip_get_interface_address (ip_lookup_main_t * lm, void * addr_fib)
 429 {
 430   uword * p = mhash_get (&lm->address_to_if_address_index, addr_fib);
 431   return p ? pool_elt_at_index (lm->if_address_pool, p[0]) : 0;
 432 }
 433
 434 u32
 435 fib_table_id_find_fib_index (fib_protocol_t proto,
 436                              u32 table_id);
 437
 438 always_inline void *
 439 ip_interface_address_get_address (ip_lookup_main_t * lm, ip_interface_address_t * a)
 440 { return mhash_key_to_mem (&lm->address_to_if_address_index, a->address_key); }
 441
 442 #define foreach_ip_interface_address(lm,a,sw_if_index,loop,body)        \
 443 do {                                                                    \
 444     vnet_main_t *_vnm = vnet_get_main();                                     \
 445     u32 _sw_if_index = sw_if_index;                                     \
 446     vnet_sw_interface_t *_swif;                                         \
 447     _swif = vnet_get_sw_interface (_vnm, _sw_if_index);                 \
 448                                                                         \
 449     /*                                                                  \
 450      * Loop => honor unnumbered interface addressing.                   \
 451      */                                                                 \
 452     if (loop && _swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)       \
 453       _sw_if_index = _swif->unnumbered_sw_if_index;                     \
 454     u32 _ia =                                                           \
 455       (vec_len((lm)->if_address_pool_index_by_sw_if_index)              \
 456        > (_sw_if_index))                                                \
 457         ? vec_elt ((lm)->if_address_pool_index_by_sw_if_index,          \
 458                    (_sw_if_index)) : (u32)~0;                           \
 459     ip_interface_address_t * _a;                                        \
 460     while (_ia != ~0)                                                   \
 461     {                                                                   \
 462         _a = pool_elt_at_index ((lm)->if_address_pool, _ia);            \
 463         _ia = _a->next_this_sw_interface;                               \
 464         (a) = _a;                                                       \
 465         body;                                                           \
 466     }                                                                   \
 467 } while (0)
 468
 469 void ip_lookup_init (ip_lookup_main_t * lm, u32 ip_lookup_node_index);
 470
 471 #endif /* included_ip_lookup_h */