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   /* Handle for this adjacency in adjacency heap. */
 177   u32 heap_handle;
 178
 179   /** Number of adjecencies in block.  Greater than 1 means multipath;
 180      otherwise equal to 1. */
 181   u16 n_adj;
 182
 183   /** Next hop after ip4-lookup. */
 184   union {
 185     ip_lookup_next_t lookup_next_index : 16;
 186     u16 lookup_next_index_as_int;
 187   };
 188
 189   /** Interface address index for this local/arp adjacency. */
 190   u32 if_address_index;
 191
 192   /** Force re-lookup in a different FIB. ~0 => normal behavior */
 193   u16 mcast_group_index;
 194
 195   /** Highest possible perf subgraph arc interposition, e.g. for ip6 ioam */
 196   u16 saved_lookup_next_index;
 197
 198   /*
 199    * link/ether-type
 200    */
 201   u8 ia_link;
 202   u8 ia_nh_proto;
 203
 204   union {
 205     union {
 206         /**
 207          * IP_LOOKUP_NEXT_ARP/IP_LOOKUP_NEXT_REWRITE
 208          *
 209          * neighbour adjacency sub-type;
 210          */
 211         struct {
 212             ip46_address_t next_hop;
 213         } nbr;
 214         /**
 215          * IP_LOOKUP_NEXT_MIDCHAIN
 216          *
 217          * A nbr adj that is also recursive. Think tunnels.
 218          * A nbr adj can transition to be of type MDICHAIN
 219          * so be sure to leave the two structs with the next_hop
 220          * fields aligned.
 221          */
 222         struct {
 223             /**
 224              * The recursive next-hop
 225              */
 226             ip46_address_t next_hop;
 227             /**
 228              * The node index of the tunnel's post rewrite/TX function.
 229              */
 230             u32 tx_function_node;
 231             /**
 232              * The next DPO to use
 233              */
 234             dpo_id_t next_dpo;
 235
 236             /**
 237              * A function to perform the post-rewrite fixup
 238              */
 239             adj_midchain_fixup_t fixup_func;
 240         } midchain;
 241         /**
 242          * IP_LOOKUP_NEXT_GLEAN
 243          *
 244          * Glean the address to ARP for from the packet's destination
 245          */
 246         struct {
 247             ip46_address_t receive_addr;
 248         } glean;
 249     } sub_type;
 250   };
 251
 252   CLIB_CACHE_LINE_ALIGN_MARK(cacheline1);
 253
 254   /* Rewrite in second/third cache lines */
 255   vnet_declare_rewrite (VLIB_BUFFER_PRE_DATA_SIZE);
 256
 257   /*
 258    * member not accessed in the data plane are relgated to the
 259    * remaining cachelines
 260    */
 261   fib_node_t ia_node;
 262 } ip_adjacency_t;
 263
 264 _Static_assert((STRUCT_OFFSET_OF(ip_adjacency_t, cacheline0) == 0),
 265                "IP adjacency cachline 0 is not offset");
 266 _Static_assert((STRUCT_OFFSET_OF(ip_adjacency_t, cacheline1) ==
 267                 CLIB_CACHE_LINE_BYTES),
 268                "IP adjacency cachline 1 is more than one cachline size offset");
 269
 270 /* An all zeros address */
 271 extern const ip46_address_t zero_addr;
 272
 273 /* IP multicast adjacency. */
 274 typedef struct {
 275   /* Handle for this adjacency in adjacency heap. */
 276   u32 heap_handle;
 277
 278   /* Number of adjecencies in block. */
 279   u32 n_adj;
 280
 281   /* Rewrite string. */
 282   vnet_declare_rewrite (64 - 2*sizeof(u32));
 283 } ip_multicast_rewrite_t;
 284
 285 typedef struct {
 286   /* ip4-multicast-rewrite next index. */
 287   u32 next_index;
 288
 289   u8 n_rewrite_bytes;
 290
 291   u8 rewrite_string[64 - 1*sizeof(u32) - 1*sizeof(u8)];
 292 } ip_multicast_rewrite_string_t;
 293
 294 typedef struct {
 295   ip_multicast_rewrite_t * rewrite_heap;
 296
 297   ip_multicast_rewrite_string_t * rewrite_strings;
 298
 299   /* Negative rewrite string index; >= 0 sw_if_index.
 300      Sorted.  Used to hash. */
 301   i32 ** adjacency_id_vector;
 302
 303   uword * adjacency_by_id_vector;
 304 } ip_multicast_lookup_main_t;
 305
 306 typedef struct {
 307   /* Key for mhash; in fact, just a byte offset into mhash key vector. */
 308   u32 address_key;
 309
 310   /* Interface which has this address. */
 311   u32 sw_if_index;
 312
 313   /* Adjacency for neighbor probe (ARP) for this interface address. */
 314   u32 neighbor_probe_adj_index;
 315
 316   /* Address (prefix) length for this interface. */
 317   u16 address_length;
 318
 319   /* Will be used for something eventually.  Primary vs. secondary? */
 320   u16 flags;
 321
 322   /* Next and previous pointers for doubly linked list of
 323      addresses per software interface. */
 324   u32 next_this_sw_interface;
 325   u32 prev_this_sw_interface;
 326 } ip_interface_address_t;
 327
 328 typedef enum {
 329   IP_LOCAL_NEXT_DROP,
 330   IP_LOCAL_NEXT_PUNT,
 331   IP_LOCAL_NEXT_UDP_LOOKUP,
 332   IP_LOCAL_NEXT_ICMP,
 333   IP_LOCAL_N_NEXT,
 334 } ip_local_next_t;
 335
 336 struct ip_lookup_main_t;
 337
 338 typedef void (* ip_add_del_adjacency_callback_t) (struct ip_lookup_main_t * lm,
 339                                                   u32 adj_index,
 340                                                   ip_adjacency_t * adj,
 341                                                   u32 is_del);
 342
 343 typedef struct ip_lookup_main_t {
 344   /* Adjacency heap. */
 345   ip_adjacency_t * adjacency_heap;
 346
 347   /** load-balance  packet/byte counters indexed by LB index. */
 348   vlib_combined_counter_main_t load_balance_counters;
 349
 350   /** any-tx-feature-enabled interface bitmap */
 351   uword * tx_sw_if_has_ip_output_features;
 352
 353   /** count of enabled features, per sw_if_index, to maintain bitmap */
 354   i16 * tx_feature_count_by_sw_if_index;
 355
 356   /** Pool of addresses that are assigned to interfaces. */
 357   ip_interface_address_t * if_address_pool;
 358
 359   /** Hash table mapping address to index in interface address pool. */
 360   mhash_t address_to_if_address_index;
 361
 362   /** Head of doubly linked list of interface addresses for each software interface.
 363      ~0 means this interface has no address. */
 364   u32 * if_address_pool_index_by_sw_if_index;
 365
 366   /** First table index to use for this interface, ~0 => none */
 367   u32 * classify_table_index_by_sw_if_index;
 368
 369   /** rx unicast, multicast, tx interface/feature configuration. */
 370   ip_config_main_t feature_config_mains[VNET_N_IP_FEAT];
 371
 372   /** Number of bytes in a fib result.  Must be at least
 373      sizeof (uword).  First word is always adjacency index. */
 374   u32 fib_result_n_bytes, fib_result_n_words;
 375
 376   format_function_t * format_fib_result;
 377
 378   /** 1 for ip6; 0 for ip4. */
 379   u32 is_ip6;
 380
 381   /** Either format_ip4_address_and_length or format_ip6_address_and_length. */
 382   format_function_t * format_address_and_length;
 383
 384   /** Special adjacency format functions */
 385   format_function_t ** special_adjacency_format_functions;
 386
 387   /** Table mapping ip protocol to ip[46]-local node next index. */
 388   u8 local_next_by_ip_protocol[256];
 389
 390   /** IP_BUILTIN_PROTOCOL_{TCP,UDP,ICMP,OTHER} by protocol in IP header. */
 391   u8 builtin_protocol_by_ip_protocol[256];
 392 } ip_lookup_main_t;
 393
 394 always_inline ip_adjacency_t *
 395 ip_get_adjacency (ip_lookup_main_t * lm,
 396                   u32 adj_index)
 397 {
 398   ip_adjacency_t * adj;
 399
 400   adj = vec_elt_at_index (lm->adjacency_heap, adj_index);
 401
 402   ASSERT (adj->heap_handle != ~0);
 403
 404   return adj;
 405 }
 406
 407 #define ip_prefetch_adjacency(lm,adj_index,type)                \
 408 do {                                                            \
 409   ip_adjacency_t * _adj = (lm)->adjacency_heap + (adj_index);   \
 410   CLIB_PREFETCH (_adj, sizeof (_adj[0]), type);                 \
 411 } while (0)
 412
 413 /* Create new block of given number of contiguous adjacencies. */
 414 ip_adjacency_t *
 415 ip_add_adjacency (ip_lookup_main_t * lm,
 416                   ip_adjacency_t * adj,
 417                   u32 n_adj,
 418                   u32 * adj_index_result);
 419
 420 clib_error_t *
 421 ip_interface_address_add_del (ip_lookup_main_t * lm,
 422                               u32 sw_if_index,
 423                               void * address,
 424                               u32 address_length,
 425                               u32 is_del,
 426                               u32 * result_index);
 427
 428 u8 *
 429 format_ip_flow_hash_config (u8 * s, va_list * args);
 430
 431 always_inline ip_interface_address_t *
 432 ip_get_interface_address (ip_lookup_main_t * lm, void * addr_fib)
 433 {
 434   uword * p = mhash_get (&lm->address_to_if_address_index, addr_fib);
 435   return p ? pool_elt_at_index (lm->if_address_pool, p[0]) : 0;
 436 }
 437
 438 u32
 439 fib_table_id_find_fib_index (fib_protocol_t proto,
 440                              u32 table_id);
 441
 442 always_inline void *
 443 ip_interface_address_get_address (ip_lookup_main_t * lm, ip_interface_address_t * a)
 444 { return mhash_key_to_mem (&lm->address_to_if_address_index, a->address_key); }
 445
 446 #define foreach_ip_interface_address(lm,a,sw_if_index,loop,body)        \
 447 do {                                                                    \
 448     vnet_main_t *_vnm = vnet_get_main();                                     \
 449     u32 _sw_if_index = sw_if_index;                                     \
 450     vnet_sw_interface_t *_swif;                                         \
 451     _swif = vnet_get_sw_interface (_vnm, _sw_if_index);                 \
 452                                                                         \
 453     /*                                                                  \
 454      * Loop => honor unnumbered interface addressing.                   \
 455      */                                                                 \
 456     if (loop && _swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)       \
 457       _sw_if_index = _swif->unnumbered_sw_if_index;                     \
 458     u32 _ia =                                                           \
 459       (vec_len((lm)->if_address_pool_index_by_sw_if_index)              \
 460        > (_sw_if_index))                                                \
 461         ? vec_elt ((lm)->if_address_pool_index_by_sw_if_index,          \
 462                    (_sw_if_index)) : (u32)~0;                           \
 463     ip_interface_address_t * _a;                                        \
 464     while (_ia != ~0)                                                   \
 465     {                                                                   \
 466         _a = pool_elt_at_index ((lm)->if_address_pool, _ia);            \
 467         _ia = _a->next_this_sw_interface;                               \
 468         (a) = _a;                                                       \
 469         body;                                                           \
 470     }                                                                   \
 471 } while (0)
 472
 473 void ip_lookup_init (ip_lookup_main_t * lm, u32 ip_lookup_node_index);
 474
 475 #endif /* included_ip_lookup_h */