src/vnet/fib/fib_path.c

   1 /*
   2  * Copyright (c) 2016 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 #include <vlib/vlib.h>
  17 #include <vnet/vnet.h>
  18 #include <vnet/ip/format.h>
  19 #include <vnet/ip/ip.h>
  20 #include <vnet/dpo/drop_dpo.h>
  21 #include <vnet/dpo/receive_dpo.h>
  22 #include <vnet/dpo/load_balance_map.h>
  23 #include <vnet/dpo/lookup_dpo.h>
  24 #include <vnet/dpo/interface_rx_dpo.h>
  25 #include <vnet/dpo/mpls_disposition.h>
  26 #include <vnet/dpo/dvr_dpo.h>
  27 #include <vnet/dpo/ip_null_dpo.h>
  28 #include <vnet/dpo/classify_dpo.h>
  29 #include <vnet/dpo/pw_cw.h>
  30
  31 #include <vnet/adj/adj.h>
  32 #include <vnet/adj/adj_mcast.h>
  33
  34 #include <vnet/fib/fib_path.h>
  35 #include <vnet/fib/fib_node.h>
  36 #include <vnet/fib/fib_table.h>
  37 #include <vnet/fib/fib_entry.h>
  38 #include <vnet/fib/fib_path_list.h>
  39 #include <vnet/fib/fib_internal.h>
  40 #include <vnet/fib/fib_urpf_list.h>
  41 #include <vnet/fib/mpls_fib.h>
  42 #include <vnet/fib/fib_path_ext.h>
  43 #include <vnet/udp/udp_encap.h>
  44 #include <vnet/bier/bier_fmask.h>
  45 #include <vnet/bier/bier_table.h>
  46 #include <vnet/bier/bier_imp.h>
  47 #include <vnet/bier/bier_disp_table.h>
  48
  49 /**
  50  * Enurmeration of path types
  51  */
  52 typedef enum fib_path_type_t_ {
  53     /**
  54      * Marker. Add new types after this one.
  55      */
  56     FIB_PATH_TYPE_FIRST = 0,
  57     /**
  58      * Attached-nexthop. An interface and a nexthop are known.
  59      */
  60     FIB_PATH_TYPE_ATTACHED_NEXT_HOP = FIB_PATH_TYPE_FIRST,
  61     /**
  62      * attached. Only the interface is known.
  63      */
  64     FIB_PATH_TYPE_ATTACHED,
  65     /**
  66      * recursive. Only the next-hop is known.
  67      */
  68     FIB_PATH_TYPE_RECURSIVE,
  69     /**
  70      * special. nothing is known. so we drop.
  71      */
  72     FIB_PATH_TYPE_SPECIAL,
  73     /**
  74      * exclusive. user provided adj.
  75      */
  76     FIB_PATH_TYPE_EXCLUSIVE,
  77     /**
  78      * deag. Link to a lookup adj in the next table
  79      */
  80     FIB_PATH_TYPE_DEAG,
  81     /**
  82      * interface receive.
  83      */
  84     FIB_PATH_TYPE_INTF_RX,
  85     /**
  86      * Path resolves via a UDP encap object.
  87      */
  88     FIB_PATH_TYPE_UDP_ENCAP,
  89     /**
  90      * receive. it's for-us.
  91      */
  92     FIB_PATH_TYPE_RECEIVE,
  93     /**
  94      * bier-imp. it's via a BIER imposition.
  95      */
  96     FIB_PATH_TYPE_BIER_IMP,
  97     /**
  98      * bier-fmask. it's via a BIER ECMP-table.
  99      */
 100     FIB_PATH_TYPE_BIER_TABLE,
 101     /**
 102      * bier-fmask. it's via a BIER f-mask.
 103      */
 104     FIB_PATH_TYPE_BIER_FMASK,
 105     /**
 106      * via a DVR.
 107      */
 108     FIB_PATH_TYPE_DVR,
 109 } __attribute__ ((packed)) fib_path_type_t;
 110
 111 #define FIB_PATH_TYPES {                                        \
 112     [FIB_PATH_TYPE_ATTACHED_NEXT_HOP] = "attached-nexthop",     \
 113     [FIB_PATH_TYPE_ATTACHED]          = "attached",             \
 114     [FIB_PATH_TYPE_RECURSIVE]         = "recursive",            \
 115     [FIB_PATH_TYPE_SPECIAL]           = "special",              \
 116     [FIB_PATH_TYPE_EXCLUSIVE]         = "exclusive",            \
 117     [FIB_PATH_TYPE_DEAG]              = "deag",                 \
 118     [FIB_PATH_TYPE_INTF_RX]           = "intf-rx",              \
 119     [FIB_PATH_TYPE_UDP_ENCAP]         = "udp-encap",            \
 120     [FIB_PATH_TYPE_RECEIVE]           = "receive",              \
 121     [FIB_PATH_TYPE_BIER_IMP]          = "bier-imp",             \
 122     [FIB_PATH_TYPE_BIER_TABLE]        = "bier-table",           \
 123     [FIB_PATH_TYPE_BIER_FMASK]        = "bier-fmask",           \
 124     [FIB_PATH_TYPE_DVR]               = "dvr",                  \
 125 }
 126
 127 /**
 128  * Enurmeration of path operational (i.e. derived) attributes
 129  */
 130 typedef enum fib_path_oper_attribute_t_ {
 131     /**
 132      * Marker. Add new types after this one.
 133      */
 134     FIB_PATH_OPER_ATTRIBUTE_FIRST = 0,
 135     /**
 136      * The path forms part of a recursive loop.
 137      */
 138     FIB_PATH_OPER_ATTRIBUTE_RECURSIVE_LOOP = FIB_PATH_OPER_ATTRIBUTE_FIRST,
 139     /**
 140      * The path is resolved
 141      */
 142     FIB_PATH_OPER_ATTRIBUTE_RESOLVED,
 143     /**
 144      * The path has become a permanent drop.
 145      */
 146     FIB_PATH_OPER_ATTRIBUTE_DROP,
 147     /**
 148      * Marker. Add new types before this one, then update it.
 149      */
 150     FIB_PATH_OPER_ATTRIBUTE_LAST = FIB_PATH_OPER_ATTRIBUTE_DROP,
 151 } __attribute__ ((packed)) fib_path_oper_attribute_t;
 152
 153 /**
 154  * The maximum number of path operational attributes
 155  */
 156 #define FIB_PATH_OPER_ATTRIBUTE_MAX (FIB_PATH_OPER_ATTRIBUTE_LAST + 1)
 157
 158 #define FIB_PATH_OPER_ATTRIBUTES {                                      \
 159     [FIB_PATH_OPER_ATTRIBUTE_RECURSIVE_LOOP] = "recursive-loop",        \
 160     [FIB_PATH_OPER_ATTRIBUTE_RESOLVED]       = "resolved",              \
 161     [FIB_PATH_OPER_ATTRIBUTE_DROP]           = "drop",                  \
 162 }
 163
 164 #define FOR_EACH_FIB_PATH_OPER_ATTRIBUTE(_item) \
 165     for (_item = FIB_PATH_OPER_ATTRIBUTE_FIRST; \
 166          _item <= FIB_PATH_OPER_ATTRIBUTE_LAST; \
 167          _item++)
 168
 169 /**
 170  * Path flags from the attributes
 171  */
 172 typedef enum fib_path_oper_flags_t_ {
 173     FIB_PATH_OPER_FLAG_NONE = 0,
 174     FIB_PATH_OPER_FLAG_RECURSIVE_LOOP = (1 << FIB_PATH_OPER_ATTRIBUTE_RECURSIVE_LOOP),
 175     FIB_PATH_OPER_FLAG_DROP = (1 << FIB_PATH_OPER_ATTRIBUTE_DROP),
 176     FIB_PATH_OPER_FLAG_RESOLVED = (1 << FIB_PATH_OPER_ATTRIBUTE_RESOLVED),
 177 } __attribute__ ((packed)) fib_path_oper_flags_t;
 178
 179 /**
 180  * A FIB path
 181  */
 182 typedef struct fib_path_t_ {
 183     /**
 184      * A path is a node in the FIB graph.
 185      */
 186     fib_node_t fp_node;
 187
 188     /**
 189      * The index of the path-list to which this path belongs
 190      */
 191     u32 fp_pl_index;
 192
 193     /**
 194      * This marks the start of the memory area used to hash
 195      * the path
 196      */
 197     STRUCT_MARK(path_hash_start);
 198
 199     /**
 200      * Configuration Flags
 201      */
 202     fib_path_cfg_flags_t fp_cfg_flags;
 203
 204     /**
 205      * The type of the path. This is the selector for the union
 206      */
 207     fib_path_type_t fp_type;
 208
 209     /**
 210      * The protocol of the next-hop, i.e. the address family of the
 211      * next-hop's address. We can't derive this from the address itself
 212      * since the address can be all zeros
 213      */
 214     dpo_proto_t fp_nh_proto;
 215
 216     /**
 217      * UCMP [unnormalised] weigth
 218      */
 219     u8 fp_weight;
 220
 221     /**
 222      * A path preference. 0 is the best.
 223      * Only paths of the best preference, that are 'up', are considered
 224      * for forwarding.
 225      */
 226     u8 fp_preference;
 227
 228     /**
 229      * per-type union of the data required to resolve the path
 230      */
 231     union {
 232         struct {
 233             /**
 234              * The next-hop
 235              */
 236             ip46_address_t fp_nh;
 237             /**
 238              * The interface
 239              */
 240             u32 fp_interface;
 241         } attached_next_hop;
 242         struct {
 243             /**
 244              * The Connected local address
 245              */
 246             fib_prefix_t fp_connected;
 247             /**
 248              * The interface
 249              */
 250             u32 fp_interface;
 251         } attached;
 252         struct {
 253             union
 254             {
 255                 /**
 256                  * The next-hop
 257                  */
 258                 ip46_address_t fp_ip;
 259                 struct {
 260                     /**
 261                      * The local label to resolve through.
 262                      */
 263                     mpls_label_t fp_local_label;
 264                     /**
 265                      * The EOS bit of the resolving label
 266                      */
 267                     mpls_eos_bit_t fp_eos;
 268                 };
 269             } fp_nh;
 270             /**
 271              * The FIB table index in which to find the next-hop.
 272              */
 273             fib_node_index_t fp_tbl_id;
 274         } recursive;
 275         struct {
 276             /**
 277              * BIER FMask ID
 278              */
 279             index_t fp_bier_fmask;
 280         } bier_fmask;
 281         struct {
 282             /**
 283              * The BIER table's ID
 284              */
 285             bier_table_id_t fp_bier_tbl;
 286         } bier_table;
 287         struct {
 288             /**
 289              * The BIER imposition object
 290              * this is part of the path's key, since the index_t
 291              * of an imposition object is the object's key.
 292              */
 293             index_t fp_bier_imp;
 294         } bier_imp;
 295         struct {
 296             /**
 297              * The FIB index in which to perfom the next lookup
 298              */
 299             fib_node_index_t fp_tbl_id;
 300             /**
 301              * The RPF-ID to tag the packets with
 302              */
 303             fib_rpf_id_t fp_rpf_id;
 304         } deag;
 305         struct {
 306         } special;
 307         struct {
 308             /**
 309              * The user provided 'exclusive' DPO
 310              */
 311             dpo_id_t fp_ex_dpo;
 312         } exclusive;
 313         struct {
 314             /**
 315              * The interface on which the local address is configured
 316              */
 317             u32 fp_interface;
 318             /**
 319              * The next-hop
 320              */
 321             ip46_address_t fp_addr;
 322         } receive;
 323         struct {
 324             /**
 325              * The interface on which the packets will be input.
 326              */
 327             u32 fp_interface;
 328         } intf_rx;
 329         struct {
 330             /**
 331              * The UDP Encap object this path resolves through
 332              */
 333             u32 fp_udp_encap_id;
 334         } udp_encap;
 335         struct {
 336             /**
 337              * The UDP Encap object this path resolves through
 338              */
 339             u32 fp_classify_table_id;
 340         } classify;
 341         struct {
 342             /**
 343              * The interface
 344              */
 345             u32 fp_interface;
 346         } dvr;
 347     };
 348     STRUCT_MARK(path_hash_end);
 349
 350     /**
 351      * Members in this last section represent information that is
 352      * dervied during resolution. It should not be copied to new paths
 353      * nor compared.
 354      */
 355
 356     /**
 357      * Operational Flags
 358      */
 359     fib_path_oper_flags_t fp_oper_flags;
 360
 361     union {
 362         /**
 363          * the resolving via fib. not part of the union, since it it not part
 364          * of the path's hash.
 365          */
 366         fib_node_index_t fp_via_fib;
 367         /**
 368          * the resolving bier-table
 369          */
 370         index_t fp_via_bier_tbl;
 371         /**
 372          * the resolving bier-fmask
 373          */
 374         index_t fp_via_bier_fmask;
 375     };
 376
 377     /**
 378      * The Data-path objects through which this path resolves for IP.
 379      */
 380     dpo_id_t fp_dpo;
 381
 382     /**
 383      * the index of this path in the parent's child list.
 384      */
 385     u32 fp_sibling;
 386 } fib_path_t;
 387
 388 /*
 389  * Array of strings/names for the path types and attributes
 390  */
 391 static const char *fib_path_type_names[] = FIB_PATH_TYPES;
 392 static const char *fib_path_oper_attribute_names[] = FIB_PATH_OPER_ATTRIBUTES;
 393 static const char *fib_path_cfg_attribute_names[]  = FIB_PATH_CFG_ATTRIBUTES;
 394
 395 /*
 396  * The memory pool from which we allocate all the paths
 397  */
 398 static fib_path_t *fib_path_pool;
 399
 400 /**
 401  * the logger
 402  */
 403 vlib_log_class_t fib_path_logger;
 404
 405 /*
 406  * Debug macro
 407  */
 408 #define FIB_PATH_DBG(_p, _fmt, _args...)                                \
 409 {                                                                       \
 410     vlib_log_debug (fib_path_logger,                                    \
 411                     "[%U]: " _fmt,                                      \
 412                     format_fib_path, fib_path_get_index(_p), 0,         \
 413                     FIB_PATH_FORMAT_FLAGS_ONE_LINE,                     \
 414                     ##_args);                                           \
 415 }
 416
 417 static fib_path_t *
 418 fib_path_get (fib_node_index_t index)
 419 {
 420     return (pool_elt_at_index(fib_path_pool, index));
 421 }
 422
 423 static fib_node_index_t
 424 fib_path_get_index (fib_path_t *path)
 425 {
 426     return (path - fib_path_pool);
 427 }
 428
 429 static fib_node_t *
 430 fib_path_get_node (fib_node_index_t index)
 431 {
 432     return ((fib_node_t*)fib_path_get(index));
 433 }
 434
 435 static fib_path_t*
 436 fib_path_from_fib_node (fib_node_t *node)
 437 {
 438     ASSERT(FIB_NODE_TYPE_PATH == node->fn_type);
 439     return ((fib_path_t*)node);
 440 }
 441
 442 u8 *
 443 format_fib_path (u8 * s, va_list * args)
 444 {
 445     fib_node_index_t path_index = va_arg (*args, fib_node_index_t);
 446     u32 indent = va_arg (*args, u32);
 447     fib_format_path_flags_t flags =  va_arg (*args, fib_format_path_flags_t);
 448     vnet_main_t * vnm = vnet_get_main();
 449     fib_path_oper_attribute_t oattr;
 450     fib_path_cfg_attribute_t cattr;
 451     fib_path_t *path;
 452     const char *eol;
 453
 454     if (flags & FIB_PATH_FORMAT_FLAGS_ONE_LINE)
 455     {
 456         eol = "";
 457     }
 458     else
 459     {
 460         eol = "\n";
 461     }
 462
 463     path = fib_path_get(path_index);
 464
 465     s = format (s, "%Upath:[%d] ", format_white_space, indent,
 466                 fib_path_get_index(path));
 467     s = format (s, "pl-index:%d ", path->fp_pl_index);
 468     s = format (s, "%U ", format_dpo_proto, path->fp_nh_proto);
 469     s = format (s, "weight=%d ", path->fp_weight);
 470     s = format (s, "pref=%d ", path->fp_preference);
 471     s = format (s, "%s: ", fib_path_type_names[path->fp_type]);
 472     if (FIB_PATH_OPER_FLAG_NONE != path->fp_oper_flags) {
 473         s = format(s, " oper-flags:");
 474         FOR_EACH_FIB_PATH_OPER_ATTRIBUTE(oattr) {
 475             if ((1<<oattr) & path->fp_oper_flags) {
 476                 s = format (s, "%s,", fib_path_oper_attribute_names[oattr]);
 477             }
 478         }
 479     }
 480     if (FIB_PATH_CFG_FLAG_NONE != path->fp_cfg_flags) {
 481         s = format(s, " cfg-flags:");
 482         FOR_EACH_FIB_PATH_CFG_ATTRIBUTE(cattr) {
 483             if ((1<<cattr) & path->fp_cfg_flags) {
 484                 s = format (s, "%s,", fib_path_cfg_attribute_names[cattr]);
 485             }
 486         }
 487     }
 488     if (!(flags & FIB_PATH_FORMAT_FLAGS_ONE_LINE))
 489         s = format(s, "\n%U", format_white_space, indent+2);
 490
 491     switch (path->fp_type)
 492     {
 493     case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
 494         s = format (s, "%U", format_ip46_address,
 495                     &path->attached_next_hop.fp_nh,
 496                     IP46_TYPE_ANY);
 497         if (path->fp_oper_flags & FIB_PATH_OPER_FLAG_DROP)
 498         {
 499             s = format (s, " if_index:%d", path->attached_next_hop.fp_interface);
 500         }
 501         else
 502         {
 503             s = format (s, " %U",
 504                         format_vnet_sw_interface_name,
 505                         vnm,
 506                         vnet_get_sw_interface(
 507                             vnm,
 508                             path->attached_next_hop.fp_interface));
 509             if (vnet_sw_interface_is_p2p(vnet_get_main(),
 510                                          path->attached_next_hop.fp_interface))
 511             {
 512                 s = format (s, " (p2p)");
 513             }
 514         }
 515         if (!dpo_id_is_valid(&path->fp_dpo))
 516         {
 517             s = format(s, "%s%Uunresolved", eol, format_white_space, indent+2);
 518         }
 519         else
 520         {
 521             s = format(s, "%s%U%U", eol,
 522                        format_white_space, indent,
 523                        format_dpo_id,
 524                        &path->fp_dpo, 13);
 525         }
 526         break;
 527     case FIB_PATH_TYPE_ATTACHED:
 528         if (path->fp_oper_flags & FIB_PATH_OPER_FLAG_DROP)
 529         {
 530             s = format (s, "if_index:%d", path->attached_next_hop.fp_interface);
 531         }
 532         else
 533         {
 534             s = format (s, " %U",
 535                         format_vnet_sw_interface_name,
 536                         vnm,
 537                         vnet_get_sw_interface(
 538                             vnm,
 539                             path->attached.fp_interface));
 540         }
 541         break;
 542     case FIB_PATH_TYPE_RECURSIVE:
 543         if (DPO_PROTO_MPLS == path->fp_nh_proto)
 544         {
 545             s = format (s, "via %U %U",
 546                         format_mpls_unicast_label,
 547                         path->recursive.fp_nh.fp_local_label,
 548                         format_mpls_eos_bit,
 549                         path->recursive.fp_nh.fp_eos);
 550         }
 551         else
 552         {
 553             s = format (s, "via %U",
 554                         format_ip46_address,
 555                         &path->recursive.fp_nh.fp_ip,
 556                         IP46_TYPE_ANY);
 557         }
 558         s = format (s, " in fib:%d",
 559                     path->recursive.fp_tbl_id,
 560                     path->fp_via_fib);
 561         s = format (s, " via-fib:%d", path->fp_via_fib);
 562         s = format (s, " via-dpo:[%U:%d]",
 563                     format_dpo_type, path->fp_dpo.dpoi_type,
 564                     path->fp_dpo.dpoi_index);
 565
 566         break;
 567     case FIB_PATH_TYPE_UDP_ENCAP:
 568         s = format (s, "UDP-encap ID:%d", path->udp_encap.fp_udp_encap_id);
 569         break;
 570     case FIB_PATH_TYPE_BIER_TABLE:
 571         s = format (s, "via bier-table:[%U}",
 572                     format_bier_table_id,
 573                     &path->bier_table.fp_bier_tbl);
 574         s = format (s, " via-dpo:[%U:%d]",
 575                     format_dpo_type, path->fp_dpo.dpoi_type,
 576                     path->fp_dpo.dpoi_index);
 577         break;
 578     case FIB_PATH_TYPE_BIER_FMASK:
 579         s = format (s, "via-fmask:%d", path->bier_fmask.fp_bier_fmask);
 580         s = format (s, " via-dpo:[%U:%d]",
 581                     format_dpo_type, path->fp_dpo.dpoi_type,
 582                     path->fp_dpo.dpoi_index);
 583         break;
 584     case FIB_PATH_TYPE_BIER_IMP:
 585         s = format (s, "via %U", format_bier_imp,
 586                     path->bier_imp.fp_bier_imp, 0, BIER_SHOW_BRIEF);
 587         break;
 588     case FIB_PATH_TYPE_DVR:
 589         s = format (s, " %U",
 590                     format_vnet_sw_interface_name,
 591                     vnm,
 592                     vnet_get_sw_interface(
 593                         vnm,
 594                         path->dvr.fp_interface));
 595         break;
 596     case FIB_PATH_TYPE_DEAG:
 597         s = format (s, " %sfib-index:%d",
 598                     (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_RPF_ID ?  "m" : ""),
 599                     path->deag.fp_tbl_id);
 600         break;
 601     case FIB_PATH_TYPE_RECEIVE:
 602     case FIB_PATH_TYPE_INTF_RX:
 603     case FIB_PATH_TYPE_SPECIAL:
 604     case FIB_PATH_TYPE_EXCLUSIVE:
 605         if (dpo_id_is_valid(&path->fp_dpo))
 606         {
 607             s = format(s, "%U", format_dpo_id,
 608                        &path->fp_dpo, indent+2);
 609         }
 610         break;
 611     }
 612     return (s);
 613 }
 614
 615 /*
 616  * fib_path_last_lock_gone
 617  *
 618  * We don't share paths, we share path lists, so the [un]lock functions
 619  * are no-ops
 620  */
 621 static void
 622 fib_path_last_lock_gone (fib_node_t *node)
 623 {
 624     ASSERT(0);
 625 }
 626
 627 static fib_path_t*
 628 fib_path_attached_next_hop_get_adj (fib_path_t *path,
 629                                     vnet_link_t link,
 630                                     dpo_id_t *dpo)
 631 {
 632     fib_node_index_t fib_path_index;
 633     fib_protocol_t nh_proto;
 634     adj_index_t ai;
 635
 636     fib_path_index = fib_path_get_index(path);
 637     nh_proto = dpo_proto_to_fib(path->fp_nh_proto);
 638
 639     if (vnet_sw_interface_is_p2p(vnet_get_main(),
 640                                  path->attached_next_hop.fp_interface))
 641     {
 642         /*
 643          * if the interface is p2p then the adj for the specific
 644          * neighbour on that link will never exist. on p2p links
 645          * the subnet address (the attached route) links to the
 646          * auto-adj (see below), we want that adj here too.
 647          */
 648         ai = adj_nbr_add_or_lock(nh_proto, link, &zero_addr,
 649                                  path->attached_next_hop.fp_interface);
 650     }
 651     else
 652     {
 653         ai = adj_nbr_add_or_lock(nh_proto, link,
 654                                  &path->attached_next_hop.fp_nh,
 655                                  path->attached_next_hop.fp_interface);
 656     }
 657
 658     dpo_set(dpo, DPO_ADJACENCY, vnet_link_to_dpo_proto(link), ai);
 659     adj_unlock(ai);
 660
 661     return (fib_path_get(fib_path_index));
 662 }
 663
 664 static void
 665 fib_path_attached_next_hop_set (fib_path_t *path)
 666 {
 667     dpo_id_t tmp = DPO_INVALID;
 668
 669     /*
 670      * resolve directly via the adjacency discribed by the
 671      * interface and next-hop
 672      */
 673     dpo_copy (&tmp, &path->fp_dpo);
 674     path = fib_path_attached_next_hop_get_adj(path,
 675                                               dpo_proto_to_link(path->fp_nh_proto),
 676                                               &tmp);
 677     dpo_copy(&path->fp_dpo, &tmp);
 678     dpo_reset(&tmp);
 679     ASSERT(dpo_is_adj(&path->fp_dpo));
 680
 681     /*
 682      * become a child of the adjacency so we receive updates
 683      * when its rewrite changes
 684      */
 685     path->fp_sibling = adj_child_add(path->fp_dpo.dpoi_index,
 686                                      FIB_NODE_TYPE_PATH,
 687                                      fib_path_get_index(path));
 688
 689     if (!vnet_sw_interface_is_up(vnet_get_main(),
 690                                  path->attached_next_hop.fp_interface) ||
 691         !adj_is_up(path->fp_dpo.dpoi_index))
 692     {
 693         path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
 694     }
 695 }
 696
 697 static void
 698 fib_path_attached_get_adj (fib_path_t *path,
 699                            vnet_link_t link,
 700                            dpo_id_t *dpo)
 701 {
 702     fib_protocol_t nh_proto;
 703
 704     nh_proto = dpo_proto_to_fib(path->fp_nh_proto);
 705
 706     if (vnet_sw_interface_is_p2p(vnet_get_main(),
 707                                  path->attached.fp_interface))
 708     {
 709         /*
 710          * point-2-point interfaces do not require a glean, since
 711          * there is nothing to ARP. Install a rewrite/nbr adj instead
 712          */
 713         adj_index_t ai;
 714
 715         ai = adj_nbr_add_or_lock(nh_proto, link, &zero_addr,
 716                                  path->attached.fp_interface);
 717
 718         dpo_set(dpo, DPO_ADJACENCY, vnet_link_to_dpo_proto(link), ai);
 719         adj_unlock(ai);
 720     }
 721     else if (vnet_sw_interface_is_nbma(vnet_get_main(),
 722                                        path->attached.fp_interface))
 723     {
 724         dpo_copy(dpo, drop_dpo_get(path->fp_nh_proto));
 725     }
 726     else
 727     {
 728         adj_index_t ai;
 729
 730         ai = adj_glean_add_or_lock(nh_proto, link,
 731                                    path->attached.fp_interface,
 732                                    &path->attached.fp_connected);
 733         dpo_set(dpo, DPO_ADJACENCY_GLEAN, vnet_link_to_dpo_proto(link), ai);
 734         adj_unlock(ai);
 735     }
 736 }
 737
 738 /*
 739  * create of update the paths recursive adj
 740  */
 741 static void
 742 fib_path_recursive_adj_update (fib_path_t *path,
 743                                fib_forward_chain_type_t fct,
 744                                dpo_id_t *dpo)
 745 {
 746     dpo_id_t via_dpo = DPO_INVALID;
 747
 748     /*
 749      * get the DPO to resolve through from the via-entry
 750      */
 751     fib_entry_contribute_forwarding(path->fp_via_fib,
 752                                     fct,
 753                                     &via_dpo);
 754
 755
 756     /*
 757      * hope for the best - clear if restrictions apply.
 758      */
 759     path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RESOLVED;
 760
 761     /*
 762      * Validate any recursion constraints and over-ride the via
 763      * adj if not met
 764      */
 765     if (path->fp_oper_flags & FIB_PATH_OPER_FLAG_RECURSIVE_LOOP)
 766     {
 767         path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
 768         dpo_copy(&via_dpo, drop_dpo_get(path->fp_nh_proto));
 769     }
 770     else if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_RESOLVE_HOST)
 771     {
 772         /*
 773          * the via FIB must be a host route.
 774          * note the via FIB just added will always be a host route
 775          * since it is an RR source added host route. So what we need to
 776          * check is whether the route has other sources. If it does then
 777          * some other source has added it as a host route. If it doesn't
 778          * then it was added only here and inherits forwarding from a cover.
 779          * the cover is not a host route.
 780          * The RR source is the lowest priority source, so we check if it
 781          * is the best. if it is there are no other sources.
 782          */
 783         if (fib_entry_get_best_source(path->fp_via_fib) >= FIB_SOURCE_RR)
 784         {
 785             path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
 786             dpo_copy(&via_dpo, drop_dpo_get(path->fp_nh_proto));
 787
 788             /*
 789              * PIC edge trigger. let the load-balance maps know
 790              */
 791             load_balance_map_path_state_change(fib_path_get_index(path));
 792         }
 793     }
 794     else if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_RESOLVE_ATTACHED)
 795     {
 796         /*
 797          * RR source entries inherit the flags from the cover, so
 798          * we can check the via directly
 799          */
 800         if (!(FIB_ENTRY_FLAG_ATTACHED & fib_entry_get_flags(path->fp_via_fib)))
 801         {
 802             path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
 803             dpo_copy(&via_dpo, drop_dpo_get(path->fp_nh_proto));
 804
 805             /*
 806              * PIC edge trigger. let the load-balance maps know
 807              */
 808             load_balance_map_path_state_change(fib_path_get_index(path));
 809         }
 810     }
 811     /*
 812      * check for over-riding factors on the FIB entry itself
 813      */
 814     if (!fib_entry_is_resolved(path->fp_via_fib))
 815     {
 816         path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
 817         dpo_copy(&via_dpo, drop_dpo_get(path->fp_nh_proto));
 818
 819         /*
 820          * PIC edge trigger. let the load-balance maps know
 821          */
 822         load_balance_map_path_state_change(fib_path_get_index(path));
 823     }
 824
 825     /*
 826      * If this path is contributing a drop, then it's not resolved
 827      */
 828     if (dpo_is_drop(&via_dpo) || load_balance_is_drop(&via_dpo))
 829     {
 830         path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
 831     }
 832
 833     /*
 834      * update the path's contributed DPO
 835      */
 836     dpo_copy(dpo, &via_dpo);
 837
 838     FIB_PATH_DBG(path, "recursive update:");
 839
 840     dpo_reset(&via_dpo);
 841 }
 842
 843 /*
 844  * re-evaulate the forwarding state for a via fmask path
 845  */
 846 static void
 847 fib_path_bier_fmask_update (fib_path_t *path,
 848                             dpo_id_t *dpo)
 849 {
 850     bier_fmask_contribute_forwarding(path->bier_fmask.fp_bier_fmask, dpo);
 851
 852     /*
 853      * if we are stakcing on the drop, then the path is not resolved
 854      */
 855     if (dpo_is_drop(dpo))
 856     {
 857         path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
 858     }
 859     else
 860     {
 861         path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RESOLVED;
 862     }
 863 }
 864
 865 /*
 866  * fib_path_is_permanent_drop
 867  *
 868  * Return !0 if the path is configured to permanently drop,
 869  * despite other attributes.
 870  */
 871 static int
 872 fib_path_is_permanent_drop (fib_path_t *path)
 873 {
 874     return ((path->fp_cfg_flags & FIB_PATH_CFG_FLAG_DROP) ||
 875             (path->fp_oper_flags & FIB_PATH_OPER_FLAG_DROP));
 876 }
 877
 878 /*
 879  * fib_path_unresolve
 880  *
 881  * Remove our dependency on the resolution target
 882  */
 883 static void
 884 fib_path_unresolve (fib_path_t *path)
 885 {
 886     /*
 887      * the forced drop path does not need unresolving
 888      */
 889     if (fib_path_is_permanent_drop(path))
 890     {
 891         return;
 892     }
 893
 894     switch (path->fp_type)
 895     {
 896     case FIB_PATH_TYPE_RECURSIVE:
 897         if (FIB_NODE_INDEX_INVALID != path->fp_via_fib)
 898         {
 899             fib_entry_child_remove(path->fp_via_fib,
 900                                    path->fp_sibling);
 901             fib_table_entry_special_remove(path->recursive.fp_tbl_id,
 902                                            fib_entry_get_prefix(path->fp_via_fib),
 903                                            FIB_SOURCE_RR);
 904             fib_table_unlock(path->recursive.fp_tbl_id,
 905                              dpo_proto_to_fib(path->fp_nh_proto),
 906                              FIB_SOURCE_RR);
 907             path->fp_via_fib = FIB_NODE_INDEX_INVALID;
 908         }
 909         break;
 910     case FIB_PATH_TYPE_BIER_FMASK:
 911         bier_fmask_child_remove(path->fp_via_bier_fmask,
 912                                 path->fp_sibling);
 913         break;
 914     case FIB_PATH_TYPE_BIER_IMP:
 915         bier_imp_unlock(path->fp_dpo.dpoi_index);
 916         break;
 917     case FIB_PATH_TYPE_BIER_TABLE:
 918         bier_table_ecmp_unlock(path->fp_via_bier_tbl);
 919         break;
 920     case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
 921     case FIB_PATH_TYPE_ATTACHED:
 922         if (dpo_is_adj(&path->fp_dpo))
 923             adj_child_remove(path->fp_dpo.dpoi_index,
 924                              path->fp_sibling);
 925         break;
 926     case FIB_PATH_TYPE_UDP_ENCAP:
 927         udp_encap_unlock(path->fp_dpo.dpoi_index);
 928         break;
 929     case FIB_PATH_TYPE_EXCLUSIVE:
 930         dpo_reset(&path->exclusive.fp_ex_dpo);
 931         break;
 932     case FIB_PATH_TYPE_SPECIAL:
 933     case FIB_PATH_TYPE_RECEIVE:
 934     case FIB_PATH_TYPE_INTF_RX:
 935     case FIB_PATH_TYPE_DEAG:
 936     case FIB_PATH_TYPE_DVR:
 937         /*
 938          * these hold only the path's DPO, which is reset below.
 939          */
 940         break;
 941     }
 942
 943     /*
 944      * release the adj we were holding and pick up the
 945      * drop just in case.
 946      */
 947     dpo_reset(&path->fp_dpo);
 948     path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
 949
 950     return;
 951 }
 952
 953 static fib_forward_chain_type_t
 954 fib_path_to_chain_type (const fib_path_t *path)
 955 {
 956     if (DPO_PROTO_MPLS == path->fp_nh_proto)
 957     {
 958         if (FIB_PATH_TYPE_RECURSIVE == path->fp_type &&
 959             MPLS_EOS == path->recursive.fp_nh.fp_eos)
 960         {
 961             return (FIB_FORW_CHAIN_TYPE_MPLS_EOS);
 962         }
 963         else
 964         {
 965             return (FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS);
 966         }
 967     }
 968     else
 969     {
 970         return (fib_forw_chain_type_from_dpo_proto(path->fp_nh_proto));
 971     }
 972 }
 973
 974 /*
 975  * fib_path_back_walk_notify
 976  *
 977  * A back walk has reach this path.
 978  */
 979 static fib_node_back_walk_rc_t
 980 fib_path_back_walk_notify (fib_node_t *node,
 981                            fib_node_back_walk_ctx_t *ctx)
 982 {
 983     fib_path_t *path;
 984
 985     path = fib_path_from_fib_node(node);
 986
 987     FIB_PATH_DBG(path, "bw:%U",
 988                  format_fib_node_bw_reason, ctx->fnbw_reason);
 989
 990     switch (path->fp_type)
 991     {
 992     case FIB_PATH_TYPE_RECURSIVE:
 993         if (FIB_NODE_BW_REASON_FLAG_EVALUATE & ctx->fnbw_reason)
 994         {
 995             /*
 996              * modify the recursive adjacency to use the new forwarding
 997              * of the via-fib.
 998              * this update is visible to packets in flight in the DP.
 999              */
1000             fib_path_recursive_adj_update(
1001                 path,
1002                 fib_path_to_chain_type(path),
1003                 &path->fp_dpo);
1004         }
1005         if ((FIB_NODE_BW_REASON_FLAG_ADJ_UPDATE & ctx->fnbw_reason) ||
1006             (FIB_NODE_BW_REASON_FLAG_ADJ_MTU    & ctx->fnbw_reason) ||
1007             (FIB_NODE_BW_REASON_FLAG_ADJ_DOWN   & ctx->fnbw_reason))
1008         {
1009             /*
1010              * ADJ updates (complete<->incomplete) do not need to propagate to
1011              * recursive entries.
1012              * The only reason its needed as far back as here, is that the adj
1013              * and the incomplete adj are a different DPO type, so the LBs need
1014              * to re-stack.
1015              * If this walk was quashed in the fib_entry, then any non-fib_path
1016              * children (like tunnels that collapse out the LB when they stack)
1017              * would not see the update.
1018              */
1019             return (FIB_NODE_BACK_WALK_CONTINUE);
1020         }
1021         break;
1022     case FIB_PATH_TYPE_BIER_FMASK:
1023         if (FIB_NODE_BW_REASON_FLAG_EVALUATE & ctx->fnbw_reason)
1024         {
1025             /*
1026              * update to use the BIER fmask's new forwading
1027              */
1028             fib_path_bier_fmask_update(path, &path->fp_dpo);
1029         }
1030         if ((FIB_NODE_BW_REASON_FLAG_ADJ_UPDATE & ctx->fnbw_reason) ||
1031             (FIB_NODE_BW_REASON_FLAG_ADJ_DOWN   & ctx->fnbw_reason))
1032         {
1033             /*
1034              * ADJ updates (complete<->incomplete) do not need to propagate to
1035              * recursive entries.
1036              * The only reason its needed as far back as here, is that the adj
1037              * and the incomplete adj are a different DPO type, so the LBs need
1038              * to re-stack.
1039              * If this walk was quashed in the fib_entry, then any non-fib_path
1040              * children (like tunnels that collapse out the LB when they stack)
1041              * would not see the update.
1042              */
1043             return (FIB_NODE_BACK_WALK_CONTINUE);
1044         }
1045         break;
1046     case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
1047         /*
1048 FIXME comment
1049          * ADJ_UPDATE backwalk pass silently through here and up to
1050          * the path-list when the multipath adj collapse occurs.
1051          * The reason we do this is that the assumtption is that VPP
1052          * runs in an environment where the Control-Plane is remote
1053          * and hence reacts slowly to link up down. In order to remove
1054          * this down link from the ECMP set quickly, we back-walk.
1055          * VPP also has dedicated CPUs, so we are not stealing resources
1056          * from the CP to do so.
1057          */
1058         if (FIB_NODE_BW_REASON_FLAG_INTERFACE_UP & ctx->fnbw_reason)
1059         {
1060             if (path->fp_oper_flags & FIB_PATH_OPER_FLAG_RESOLVED)
1061             {
1062                 /*
1063                  * alreday resolved. no need to walk back again
1064                  */
1065                 return (FIB_NODE_BACK_WALK_CONTINUE);
1066             }
1067             path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RESOLVED;
1068         }
1069         if (FIB_NODE_BW_REASON_FLAG_INTERFACE_DOWN & ctx->fnbw_reason)
1070         {
1071             if (!(path->fp_oper_flags & FIB_PATH_OPER_FLAG_RESOLVED))
1072             {
1073                 /*
1074                  * alreday unresolved. no need to walk back again
1075                  */
1076                 return (FIB_NODE_BACK_WALK_CONTINUE);
1077             }
1078             path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
1079         }
1080         if (FIB_NODE_BW_REASON_FLAG_INTERFACE_DELETE & ctx->fnbw_reason)
1081         {
1082             /*
1083              * The interface this path resolves through has been deleted.
1084              * This will leave the path in a permanent drop state. The route
1085              * needs to be removed and readded (and hence the path-list deleted)
1086              * before it can forward again.
1087              */
1088             fib_path_unresolve(path);
1089             path->fp_oper_flags |= FIB_PATH_OPER_FLAG_DROP;
1090         }
1091         if (FIB_NODE_BW_REASON_FLAG_ADJ_UPDATE & ctx->fnbw_reason)
1092         {
1093             /*
1094              * restack the DPO to pick up the correct DPO sub-type
1095              */
1096             dpo_id_t tmp = DPO_INVALID;
1097             uword if_is_up;
1098
1099             if_is_up = vnet_sw_interface_is_up(
1100                            vnet_get_main(),
1101                            path->attached_next_hop.fp_interface);
1102
1103             dpo_copy (&tmp, &path->fp_dpo);
1104             path = fib_path_attached_next_hop_get_adj(
1105                 path,
1106                 dpo_proto_to_link(path->fp_nh_proto),
1107                 &tmp);
1108             dpo_copy(&path->fp_dpo, &tmp);
1109             dpo_reset(&tmp);
1110
1111             path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
1112             if (if_is_up && adj_is_up(path->fp_dpo.dpoi_index))
1113             {
1114                 path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RESOLVED;
1115             }
1116
1117             if (!if_is_up)
1118             {
1119                 /*
1120                  * If the interface is not up there is no reason to walk
1121                  * back to children. if we did they would only evalute
1122                  * that this path is unresolved and hence it would
1123                  * not contribute the adjacency - so it would be wasted
1124                  * CPU time.
1125                  */
1126                 return (FIB_NODE_BACK_WALK_CONTINUE);
1127             }
1128         }
1129         if (FIB_NODE_BW_REASON_FLAG_ADJ_DOWN & ctx->fnbw_reason)
1130         {
1131             if (!(path->fp_oper_flags & FIB_PATH_OPER_FLAG_RESOLVED))
1132             {
1133                 /*
1134                  * alreday unresolved. no need to walk back again
1135                  */
1136                 return (FIB_NODE_BACK_WALK_CONTINUE);
1137             }
1138             /*
1139              * the adj has gone down. the path is no longer resolved.
1140              */
1141             path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
1142         }
1143         break;
1144     case FIB_PATH_TYPE_ATTACHED:
1145     case FIB_PATH_TYPE_DVR:
1146         /*
1147          * FIXME; this could schedule a lower priority walk, since attached
1148          * routes are not usually in ECMP configurations so the backwalk to
1149          * the FIB entry does not need to be high priority
1150          */
1151         if (FIB_NODE_BW_REASON_FLAG_INTERFACE_UP & ctx->fnbw_reason)
1152         {
1153             path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RESOLVED;
1154         }
1155         if (FIB_NODE_BW_REASON_FLAG_INTERFACE_DOWN & ctx->fnbw_reason)
1156         {
1157             path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
1158         }
1159         if (FIB_NODE_BW_REASON_FLAG_INTERFACE_DELETE & ctx->fnbw_reason)
1160         {
1161             fib_path_unresolve(path);
1162             path->fp_oper_flags |= FIB_PATH_OPER_FLAG_DROP;
1163         }
1164         break;
1165     case FIB_PATH_TYPE_UDP_ENCAP:
1166     {
1167         dpo_id_t via_dpo = DPO_INVALID;
1168
1169         /*
1170          * hope for the best - clear if restrictions apply.
1171          */
1172         path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RESOLVED;
1173
1174         udp_encap_contribute_forwarding(path->udp_encap.fp_udp_encap_id,
1175                                         path->fp_nh_proto,
1176                                         &via_dpo);
1177         /*
1178          * If this path is contributing a drop, then it's not resolved
1179          */
1180         if (dpo_is_drop(&via_dpo) || load_balance_is_drop(&via_dpo))
1181         {
1182             path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
1183         }
1184
1185         /*
1186          * update the path's contributed DPO
1187          */
1188         dpo_copy(&path->fp_dpo, &via_dpo);
1189         dpo_reset(&via_dpo);
1190         break;
1191     }
1192     case FIB_PATH_TYPE_INTF_RX:
1193         ASSERT(0);
1194     case FIB_PATH_TYPE_DEAG:
1195         /*
1196          * FIXME When VRF delete is allowed this will need a poke.
1197          */
1198     case FIB_PATH_TYPE_SPECIAL:
1199     case FIB_PATH_TYPE_RECEIVE:
1200     case FIB_PATH_TYPE_EXCLUSIVE:
1201     case FIB_PATH_TYPE_BIER_TABLE:
1202     case FIB_PATH_TYPE_BIER_IMP:
1203         /*
1204          * these path types have no parents. so to be
1205          * walked from one is unexpected.
1206          */
1207         ASSERT(0);
1208         break;
1209     }
1210
1211     /*
1212      * propagate the backwalk further to the path-list
1213      */
1214     fib_path_list_back_walk(path->fp_pl_index, ctx);
1215
1216     return (FIB_NODE_BACK_WALK_CONTINUE);
1217 }
1218
1219 static void
1220 fib_path_memory_show (void)
1221 {
1222     fib_show_memory_usage("Path",
1223                           pool_elts(fib_path_pool),
1224                           pool_len(fib_path_pool),
1225                           sizeof(fib_path_t));
1226 }
1227
1228 /*
1229  * The FIB path's graph node virtual function table
1230  */
1231 static const fib_node_vft_t fib_path_vft = {
1232     .fnv_get = fib_path_get_node,
1233     .fnv_last_lock = fib_path_last_lock_gone,
1234     .fnv_back_walk = fib_path_back_walk_notify,
1235     .fnv_mem_show = fib_path_memory_show,
1236 };
1237
1238 static fib_path_cfg_flags_t
1239 fib_path_route_flags_to_cfg_flags (const fib_route_path_t *rpath)
1240 {
1241     fib_path_cfg_flags_t cfg_flags = FIB_PATH_CFG_FLAG_NONE;
1242
1243     if (rpath->frp_flags & FIB_ROUTE_PATH_POP_PW_CW)
1244         cfg_flags |= FIB_PATH_CFG_FLAG_POP_PW_CW;
1245     if (rpath->frp_flags & FIB_ROUTE_PATH_RESOLVE_VIA_HOST)
1246         cfg_flags |= FIB_PATH_CFG_FLAG_RESOLVE_HOST;
1247     if (rpath->frp_flags & FIB_ROUTE_PATH_RESOLVE_VIA_ATTACHED)
1248         cfg_flags |= FIB_PATH_CFG_FLAG_RESOLVE_ATTACHED;
1249     if (rpath->frp_flags & FIB_ROUTE_PATH_LOCAL)
1250         cfg_flags |= FIB_PATH_CFG_FLAG_LOCAL;
1251     if (rpath->frp_flags & FIB_ROUTE_PATH_ATTACHED)
1252         cfg_flags |= FIB_PATH_CFG_FLAG_ATTACHED;
1253     if (rpath->frp_flags & FIB_ROUTE_PATH_INTF_RX)
1254         cfg_flags |= FIB_PATH_CFG_FLAG_INTF_RX;
1255     if (rpath->frp_flags & FIB_ROUTE_PATH_RPF_ID)
1256         cfg_flags |= FIB_PATH_CFG_FLAG_RPF_ID;
1257     if (rpath->frp_flags & FIB_ROUTE_PATH_EXCLUSIVE)
1258         cfg_flags |= FIB_PATH_CFG_FLAG_EXCLUSIVE;
1259     if (rpath->frp_flags & FIB_ROUTE_PATH_DROP)
1260         cfg_flags |= FIB_PATH_CFG_FLAG_DROP;
1261     if (rpath->frp_flags & FIB_ROUTE_PATH_SOURCE_LOOKUP)
1262         cfg_flags |= FIB_PATH_CFG_FLAG_DEAG_SRC;
1263     if (rpath->frp_flags & FIB_ROUTE_PATH_ICMP_UNREACH)
1264         cfg_flags |= FIB_PATH_CFG_FLAG_ICMP_UNREACH;
1265     if (rpath->frp_flags & FIB_ROUTE_PATH_ICMP_PROHIBIT)
1266         cfg_flags |= FIB_PATH_CFG_FLAG_ICMP_PROHIBIT;
1267     if (rpath->frp_flags & FIB_ROUTE_PATH_GLEAN)
1268         cfg_flags |= FIB_PATH_CFG_FLAG_GLEAN;
1269
1270     return (cfg_flags);
1271 }
1272
1273 /*
1274  * fib_path_create
1275  *
1276  * Create and initialise a new path object.
1277  * return the index of the path.
1278  */
1279 fib_node_index_t
1280 fib_path_create (fib_node_index_t pl_index,
1281                  const fib_route_path_t *rpath)
1282 {
1283     fib_path_t *path;
1284
1285     pool_get(fib_path_pool, path);
1286     clib_memset(path, 0, sizeof(*path));
1287
1288     fib_node_init(&path->fp_node,
1289                   FIB_NODE_TYPE_PATH);
1290
1291     dpo_reset(&path->fp_dpo);
1292     path->fp_pl_index = pl_index;
1293     path->fp_nh_proto = rpath->frp_proto;
1294     path->fp_via_fib = FIB_NODE_INDEX_INVALID;
1295     path->fp_weight = rpath->frp_weight;
1296     if (0 == path->fp_weight)
1297     {
1298         /*
1299          * a weight of 0 is a meaningless value. We could either reject it, and thus force
1300          * clients to always use 1, or we can accept it and fixup approrpiately.
1301          */
1302         path->fp_weight = 1;
1303     }
1304     path->fp_preference = rpath->frp_preference;
1305     path->fp_cfg_flags = fib_path_route_flags_to_cfg_flags(rpath);
1306
1307     /*
1308      * deduce the path's tpye from the parementers and save what is needed.
1309      */
1310     if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_LOCAL)
1311     {
1312         path->fp_type = FIB_PATH_TYPE_RECEIVE;
1313         path->receive.fp_interface = rpath->frp_sw_if_index;
1314         path->receive.fp_addr = rpath->frp_addr;
1315     }
1316     else if (rpath->frp_flags & FIB_ROUTE_PATH_UDP_ENCAP)
1317     {
1318         path->fp_type = FIB_PATH_TYPE_UDP_ENCAP;
1319         path->udp_encap.fp_udp_encap_id = rpath->frp_udp_encap_id;
1320     }
1321     else if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_INTF_RX)
1322     {
1323         path->fp_type = FIB_PATH_TYPE_INTF_RX;
1324         path->intf_rx.fp_interface = rpath->frp_sw_if_index;
1325     }
1326     else if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_RPF_ID)
1327     {
1328         path->fp_type = FIB_PATH_TYPE_DEAG;
1329         path->deag.fp_tbl_id = rpath->frp_fib_index;
1330         path->deag.fp_rpf_id = rpath->frp_rpf_id;
1331     }
1332     else if (rpath->frp_flags & FIB_ROUTE_PATH_BIER_FMASK)
1333     {
1334         path->fp_type = FIB_PATH_TYPE_BIER_FMASK;
1335         path->bier_fmask.fp_bier_fmask = rpath->frp_bier_fmask;
1336     }
1337     else if (rpath->frp_flags & FIB_ROUTE_PATH_BIER_IMP)
1338     {
1339         path->fp_type = FIB_PATH_TYPE_BIER_IMP;
1340         path->bier_imp.fp_bier_imp = rpath->frp_bier_imp;
1341     }
1342     else if (rpath->frp_flags & FIB_ROUTE_PATH_BIER_TABLE)
1343     {
1344         path->fp_type = FIB_PATH_TYPE_BIER_TABLE;
1345         path->bier_table.fp_bier_tbl = rpath->frp_bier_tbl;
1346     }
1347     else if (rpath->frp_flags & FIB_ROUTE_PATH_DEAG)
1348     {
1349         path->fp_type = FIB_PATH_TYPE_DEAG;
1350         path->deag.fp_tbl_id = rpath->frp_fib_index;
1351     }
1352     else if (rpath->frp_flags & FIB_ROUTE_PATH_DVR)
1353     {
1354         path->fp_type = FIB_PATH_TYPE_DVR;
1355         path->dvr.fp_interface = rpath->frp_sw_if_index;
1356     }
1357     else if (rpath->frp_flags & FIB_ROUTE_PATH_EXCLUSIVE)
1358     {
1359         path->fp_type = FIB_PATH_TYPE_EXCLUSIVE;
1360         dpo_copy(&path->exclusive.fp_ex_dpo, &rpath->dpo);
1361     }
1362     else if ((path->fp_cfg_flags & FIB_PATH_CFG_FLAG_ICMP_PROHIBIT) ||
1363         (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_ICMP_UNREACH))
1364     {
1365         path->fp_type = FIB_PATH_TYPE_SPECIAL;
1366     }
1367     else if ((path->fp_cfg_flags & FIB_PATH_CFG_FLAG_CLASSIFY))
1368     {
1369         path->fp_type = FIB_PATH_TYPE_SPECIAL;
1370         path->classify.fp_classify_table_id = rpath->frp_classify_table_id;
1371     }
1372     else if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_GLEAN)
1373     {
1374         path->fp_type = FIB_PATH_TYPE_ATTACHED;
1375         path->attached.fp_interface = rpath->frp_sw_if_index;
1376         path->attached.fp_connected = rpath->frp_connected;
1377     }
1378     else if (~0 != rpath->frp_sw_if_index)
1379     {
1380         if (ip46_address_is_zero(&rpath->frp_addr))
1381         {
1382             path->fp_type = FIB_PATH_TYPE_ATTACHED;
1383             path->attached.fp_interface = rpath->frp_sw_if_index;
1384         }
1385         else
1386         {
1387             path->fp_type = FIB_PATH_TYPE_ATTACHED_NEXT_HOP;
1388             path->attached_next_hop.fp_interface = rpath->frp_sw_if_index;
1389             path->attached_next_hop.fp_nh = rpath->frp_addr;
1390         }
1391     }
1392     else
1393     {
1394         if (ip46_address_is_zero(&rpath->frp_addr))
1395         {
1396             if (~0 == rpath->frp_fib_index)
1397             {
1398                 path->fp_type = FIB_PATH_TYPE_SPECIAL;
1399             }
1400             else
1401             {
1402                 path->fp_type = FIB_PATH_TYPE_DEAG;
1403                 path->deag.fp_tbl_id = rpath->frp_fib_index;
1404                 path->deag.fp_rpf_id = ~0;
1405             }
1406         }
1407         else
1408         {
1409             path->fp_type = FIB_PATH_TYPE_RECURSIVE;
1410             if (DPO_PROTO_MPLS == path->fp_nh_proto)
1411             {
1412                 path->recursive.fp_nh.fp_local_label = rpath->frp_local_label;
1413                 path->recursive.fp_nh.fp_eos = rpath->frp_eos;
1414             }
1415             else
1416             {
1417                 path->recursive.fp_nh.fp_ip = rpath->frp_addr;
1418             }
1419             path->recursive.fp_tbl_id = rpath->frp_fib_index;
1420         }
1421     }
1422
1423     FIB_PATH_DBG(path, "create");
1424
1425     return (fib_path_get_index(path));
1426 }
1427
1428 /*
1429  * fib_path_create_special
1430  *
1431  * Create and initialise a new path object.
1432  * return the index of the path.
1433  */
1434 fib_node_index_t
1435 fib_path_create_special (fib_node_index_t pl_index,
1436                          dpo_proto_t nh_proto,
1437                          fib_path_cfg_flags_t flags,
1438                          const dpo_id_t *dpo)
1439 {
1440     fib_path_t *path;
1441
1442     pool_get(fib_path_pool, path);
1443     clib_memset(path, 0, sizeof(*path));
1444
1445     fib_node_init(&path->fp_node,
1446                   FIB_NODE_TYPE_PATH);
1447     dpo_reset(&path->fp_dpo);
1448
1449     path->fp_pl_index = pl_index;
1450     path->fp_weight = 1;
1451     path->fp_preference = 0;
1452     path->fp_nh_proto = nh_proto;
1453     path->fp_via_fib = FIB_NODE_INDEX_INVALID;
1454     path->fp_cfg_flags = flags;
1455
1456     if (FIB_PATH_CFG_FLAG_DROP & flags)
1457     {
1458         path->fp_type = FIB_PATH_TYPE_SPECIAL;
1459     }
1460     else if (FIB_PATH_CFG_FLAG_LOCAL & flags)
1461     {
1462         path->fp_type = FIB_PATH_TYPE_RECEIVE;
1463         path->attached.fp_interface = FIB_NODE_INDEX_INVALID;
1464     }
1465     else
1466     {
1467         path->fp_type = FIB_PATH_TYPE_EXCLUSIVE;
1468         ASSERT(NULL != dpo);
1469         dpo_copy(&path->exclusive.fp_ex_dpo, dpo);
1470     }
1471
1472     return (fib_path_get_index(path));
1473 }
1474
1475 /*
1476  * fib_path_copy
1477  *
1478  * Copy a path. return index of new path.
1479  */
1480 fib_node_index_t
1481 fib_path_copy (fib_node_index_t path_index,
1482                fib_node_index_t path_list_index)
1483 {
1484     fib_path_t *path, *orig_path;
1485
1486     pool_get(fib_path_pool, path);
1487
1488     orig_path = fib_path_get(path_index);
1489     ASSERT(NULL != orig_path);
1490
1491     clib_memcpy(path, orig_path, sizeof(*path));
1492
1493     FIB_PATH_DBG(path, "create-copy:%d", path_index);
1494
1495     /*
1496      * reset the dynamic section
1497      */
1498     fib_node_init(&path->fp_node, FIB_NODE_TYPE_PATH);
1499     path->fp_oper_flags     = FIB_PATH_OPER_FLAG_NONE;
1500     path->fp_pl_index  = path_list_index;
1501     path->fp_via_fib   = FIB_NODE_INDEX_INVALID;
1502     clib_memset(&path->fp_dpo, 0, sizeof(path->fp_dpo));
1503     dpo_reset(&path->fp_dpo);
1504
1505     return (fib_path_get_index(path));
1506 }
1507
1508 /*
1509  * fib_path_destroy
1510  *
1511  * destroy a path that is no longer required
1512  */
1513 void
1514 fib_path_destroy (fib_node_index_t path_index)
1515 {
1516     fib_path_t *path;
1517
1518     path = fib_path_get(path_index);
1519
1520     ASSERT(NULL != path);
1521     FIB_PATH_DBG(path, "destroy");
1522
1523     fib_path_unresolve(path);
1524
1525     fib_node_deinit(&path->fp_node);
1526     pool_put(fib_path_pool, path);
1527 }
1528
1529 /*
1530  * fib_path_destroy
1531  *
1532  * destroy a path that is no longer required
1533  */
1534 uword
1535 fib_path_hash (fib_node_index_t path_index)
1536 {
1537     fib_path_t *path;
1538
1539     path = fib_path_get(path_index);
1540
1541     return (hash_memory(STRUCT_MARK_PTR(path, path_hash_start),
1542                         (STRUCT_OFFSET_OF(fib_path_t, path_hash_end) -
1543                          STRUCT_OFFSET_OF(fib_path_t, path_hash_start)),
1544                         0));
1545 }
1546
1547 /*
1548  * fib_path_cmp_i
1549  *
1550  * Compare two paths for equivalence.
1551  */
1552 static int
1553 fib_path_cmp_i (const fib_path_t *path1,
1554                 const fib_path_t *path2)
1555 {
1556     int res;
1557
1558     res = 1;
1559
1560     /*
1561      * paths of different types and protocol are not equal.
1562      * different weights and/or preference only are the same path.
1563      */
1564     if (path1->fp_type != path2->fp_type)
1565     {
1566         res = (path1->fp_type - path2->fp_type);
1567     }
1568     else if (path1->fp_nh_proto != path2->fp_nh_proto)
1569     {
1570         res = (path1->fp_nh_proto - path2->fp_nh_proto);
1571     }
1572     else
1573     {
1574         /*
1575          * both paths are of the same type.
1576          * consider each type and its attributes in turn.
1577          */
1578         switch (path1->fp_type)
1579         {
1580         case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
1581             res = ip46_address_cmp(&path1->attached_next_hop.fp_nh,
1582                                    &path2->attached_next_hop.fp_nh);
1583             if (0 == res) {
1584                 res = (path1->attached_next_hop.fp_interface -
1585                        path2->attached_next_hop.fp_interface);
1586             }
1587             break;
1588         case FIB_PATH_TYPE_ATTACHED:
1589             res = (path1->attached.fp_interface -
1590                    path2->attached.fp_interface);
1591             break;
1592         case FIB_PATH_TYPE_RECURSIVE:
1593             res = ip46_address_cmp(&path1->recursive.fp_nh.fp_ip,
1594                                    &path2->recursive.fp_nh.fp_ip);
1595
1596             if (0 == res)
1597             {
1598                 res = (path1->recursive.fp_tbl_id - path2->recursive.fp_tbl_id);
1599             }
1600             break;
1601         case FIB_PATH_TYPE_BIER_FMASK:
1602             res = (path1->bier_fmask.fp_bier_fmask -
1603                    path2->bier_fmask.fp_bier_fmask);
1604             break;
1605         case FIB_PATH_TYPE_BIER_IMP:
1606             res = (path1->bier_imp.fp_bier_imp -
1607                    path2->bier_imp.fp_bier_imp);
1608             break;
1609         case FIB_PATH_TYPE_BIER_TABLE:
1610             res = bier_table_id_cmp(&path1->bier_table.fp_bier_tbl,
1611                                     &path2->bier_table.fp_bier_tbl);
1612             break;
1613         case FIB_PATH_TYPE_DEAG:
1614             res = (path1->deag.fp_tbl_id - path2->deag.fp_tbl_id);
1615             if (0 == res)
1616             {
1617                 res = (path1->deag.fp_rpf_id - path2->deag.fp_rpf_id);
1618             }
1619             break;
1620         case FIB_PATH_TYPE_INTF_RX:
1621             res = (path1->intf_rx.fp_interface - path2->intf_rx.fp_interface);
1622             break;
1623         case FIB_PATH_TYPE_UDP_ENCAP:
1624             res = (path1->udp_encap.fp_udp_encap_id - path2->udp_encap.fp_udp_encap_id);
1625             break;
1626         case FIB_PATH_TYPE_DVR:
1627             res = (path1->dvr.fp_interface - path2->dvr.fp_interface);
1628             break;
1629         case FIB_PATH_TYPE_EXCLUSIVE:
1630             res = dpo_cmp(&path1->exclusive.fp_ex_dpo, &path2->exclusive.fp_ex_dpo);
1631             break;
1632         case FIB_PATH_TYPE_SPECIAL:
1633         case FIB_PATH_TYPE_RECEIVE:
1634             res = 0;
1635             break;
1636         }
1637     }
1638     return (res);
1639 }
1640
1641 /*
1642  * fib_path_cmp_for_sort
1643  *
1644  * Compare two paths for equivalence. Used during path sorting.
1645  * As usual 0 means equal.
1646  */
1647 int
1648 fib_path_cmp_for_sort (void * v1,
1649                        void * v2)
1650 {
1651     fib_node_index_t *pi1 = v1, *pi2 = v2;
1652     fib_path_t *path1, *path2;
1653
1654     path1 = fib_path_get(*pi1);
1655     path2 = fib_path_get(*pi2);
1656
1657     /*
1658      * when sorting paths we want the highest preference paths
1659      * first, so that the choices set built is in prefernce order
1660      */
1661     if (path1->fp_preference != path2->fp_preference)
1662     {
1663         return (path1->fp_preference - path2->fp_preference);
1664     }
1665
1666     return (fib_path_cmp_i(path1, path2));
1667 }
1668
1669 /*
1670  * fib_path_cmp
1671  *
1672  * Compare two paths for equivalence.
1673  */
1674 int
1675 fib_path_cmp (fib_node_index_t pi1,
1676               fib_node_index_t pi2)
1677 {
1678     fib_path_t *path1, *path2;
1679
1680     path1 = fib_path_get(pi1);
1681     path2 = fib_path_get(pi2);
1682
1683     return (fib_path_cmp_i(path1, path2));
1684 }
1685
1686 int
1687 fib_path_cmp_w_route_path (fib_node_index_t path_index,
1688                            const fib_route_path_t *rpath)
1689 {
1690     fib_path_t *path;
1691     int res;
1692
1693     path = fib_path_get(path_index);
1694
1695     res = 1;
1696
1697     if (path->fp_weight != rpath->frp_weight)
1698     {
1699         res = (path->fp_weight - rpath->frp_weight);
1700     }
1701     else
1702     {
1703         /*
1704          * both paths are of the same type.
1705          * consider each type and its attributes in turn.
1706          */
1707         switch (path->fp_type)
1708         {
1709         case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
1710             res = ip46_address_cmp(&path->attached_next_hop.fp_nh,
1711                                    &rpath->frp_addr);
1712             if (0 == res)
1713             {
1714                 res = (path->attached_next_hop.fp_interface -
1715                        rpath->frp_sw_if_index);
1716             }
1717             break;
1718         case FIB_PATH_TYPE_ATTACHED:
1719             res = (path->attached.fp_interface - rpath->frp_sw_if_index);
1720             break;
1721         case FIB_PATH_TYPE_RECURSIVE:
1722             if (DPO_PROTO_MPLS == path->fp_nh_proto)
1723             {
1724                 res = path->recursive.fp_nh.fp_local_label - rpath->frp_local_label;
1725
1726                 if (res == 0)
1727                 {
1728                     res = path->recursive.fp_nh.fp_eos - rpath->frp_eos;
1729                 }
1730             }
1731             else
1732             {
1733                 res = ip46_address_cmp(&path->recursive.fp_nh.fp_ip,
1734                                        &rpath->frp_addr);
1735             }
1736
1737             if (0 == res)
1738             {
1739                 res = (path->recursive.fp_tbl_id - rpath->frp_fib_index);
1740             }
1741             break;
1742         case FIB_PATH_TYPE_BIER_FMASK:
1743             res = (path->bier_fmask.fp_bier_fmask - rpath->frp_bier_fmask);
1744             break;
1745         case FIB_PATH_TYPE_BIER_IMP:
1746             res = (path->bier_imp.fp_bier_imp - rpath->frp_bier_imp);
1747             break;
1748         case FIB_PATH_TYPE_BIER_TABLE:
1749             res = bier_table_id_cmp(&path->bier_table.fp_bier_tbl,
1750                                     &rpath->frp_bier_tbl);
1751             break;
1752         case FIB_PATH_TYPE_INTF_RX:
1753             res = (path->intf_rx.fp_interface - rpath->frp_sw_if_index);
1754             break;
1755         case FIB_PATH_TYPE_UDP_ENCAP:
1756             res = (path->udp_encap.fp_udp_encap_id - rpath->frp_udp_encap_id);
1757             break;
1758         case FIB_PATH_TYPE_DEAG:
1759             res = (path->deag.fp_tbl_id - rpath->frp_fib_index);
1760             if (0 == res)
1761             {
1762                 res = (path->deag.fp_rpf_id - rpath->frp_rpf_id);
1763             }
1764             break;
1765         case FIB_PATH_TYPE_DVR:
1766             res = (path->dvr.fp_interface - rpath->frp_sw_if_index);
1767             break;
1768         case FIB_PATH_TYPE_EXCLUSIVE:
1769             res = dpo_cmp(&path->exclusive.fp_ex_dpo, &rpath->dpo);
1770             break;
1771         case FIB_PATH_TYPE_RECEIVE:
1772             if (rpath->frp_flags & FIB_ROUTE_PATH_LOCAL)
1773             {
1774                 res = 0;
1775             }
1776             else
1777             {
1778                 res = 1;
1779             }
1780             break;
1781         case FIB_PATH_TYPE_SPECIAL:
1782             res = 0;
1783             break;
1784         }
1785     }
1786     return (res);
1787 }
1788
1789 /*
1790  * fib_path_recursive_loop_detect
1791  *
1792  * A forward walk of the FIB object graph to detect for a cycle/loop. This
1793  * walk is initiated when an entry is linking to a new path list or from an old.
1794  * The entry vector passed contains all the FIB entrys that are children of this
1795  * path (it is all the entries encountered on the walk so far). If this vector
1796  * contains the entry this path resolve via, then a loop is about to form.
1797  * The loop must be allowed to form, since we need the dependencies in place
1798  * so that we can track when the loop breaks.
1799  * However, we MUST not produce a loop in the forwarding graph (else packets
1800  * would loop around the switch path until the loop breaks), so we mark recursive
1801  * paths as looped so that they do not contribute forwarding information.
1802  * By marking the path as looped, an etry such as;
1803  *    X/Y
1804  *     via a.a.a.a (looped)
1805  *     via b.b.b.b (not looped)
1806  * can still forward using the info provided by b.b.b.b only
1807  */
1808 int
1809 fib_path_recursive_loop_detect (fib_node_index_t path_index,
1810                                 fib_node_index_t **entry_indicies)
1811 {
1812     fib_path_t *path;
1813
1814     path = fib_path_get(path_index);
1815
1816     /*
1817      * the forced drop path is never looped, cos it is never resolved.
1818      */
1819     if (fib_path_is_permanent_drop(path))
1820     {
1821         return (0);
1822     }
1823
1824     switch (path->fp_type)
1825     {
1826     case FIB_PATH_TYPE_RECURSIVE:
1827     {
1828         fib_node_index_t *entry_index, *entries;
1829         int looped = 0;
1830         entries = *entry_indicies;
1831
1832         vec_foreach(entry_index, entries) {
1833             if (*entry_index == path->fp_via_fib)
1834             {
1835                 /*
1836                  * the entry that is about to link to this path-list (or
1837                  * one of this path-list's children) is the same entry that
1838                  * this recursive path resolves through. this is a cycle.
1839                  * abort the walk.
1840                  */
1841                 looped = 1;
1842                 break;
1843             }
1844         }
1845
1846         if (looped)
1847         {
1848             FIB_PATH_DBG(path, "recursive loop formed");
1849             path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RECURSIVE_LOOP;
1850
1851             dpo_copy(&path->fp_dpo, drop_dpo_get(path->fp_nh_proto));
1852         }
1853         else
1854         {
1855             /*
1856              * no loop here yet. keep forward walking the graph.
1857              */
1858             if (fib_entry_recursive_loop_detect(path->fp_via_fib, entry_indicies))
1859             {
1860                 FIB_PATH_DBG(path, "recursive loop formed");
1861                 path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RECURSIVE_LOOP;
1862             }
1863             else
1864             {
1865                 FIB_PATH_DBG(path, "recursive loop cleared");
1866                 path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RECURSIVE_LOOP;
1867             }
1868         }
1869         break;
1870     }
1871     case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
1872     case FIB_PATH_TYPE_ATTACHED:
1873         if (dpo_is_adj(&path->fp_dpo) &&
1874             adj_recursive_loop_detect(path->fp_dpo.dpoi_index,
1875                                       entry_indicies))
1876         {
1877             FIB_PATH_DBG(path, "recursive loop formed");
1878             path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RECURSIVE_LOOP;
1879         }
1880         else
1881         {
1882             FIB_PATH_DBG(path, "recursive loop cleared");
1883             path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RECURSIVE_LOOP;
1884         }
1885         break;
1886     case FIB_PATH_TYPE_SPECIAL:
1887     case FIB_PATH_TYPE_DEAG:
1888     case FIB_PATH_TYPE_DVR:
1889     case FIB_PATH_TYPE_RECEIVE:
1890     case FIB_PATH_TYPE_INTF_RX:
1891     case FIB_PATH_TYPE_UDP_ENCAP:
1892     case FIB_PATH_TYPE_EXCLUSIVE:
1893     case FIB_PATH_TYPE_BIER_FMASK:
1894     case FIB_PATH_TYPE_BIER_TABLE:
1895     case FIB_PATH_TYPE_BIER_IMP:
1896         /*
1897          * these path types cannot be part of a loop, since they are the leaves
1898          * of the graph.
1899          */
1900         break;
1901     }
1902
1903     return (fib_path_is_looped(path_index));
1904 }
1905
1906 int
1907 fib_path_resolve (fib_node_index_t path_index)
1908 {
1909     fib_path_t *path;
1910
1911     path = fib_path_get(path_index);
1912
1913     /*
1914      * hope for the best.
1915      */
1916     path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RESOLVED;
1917
1918     /*
1919      * the forced drop path resolves via the drop adj
1920      */
1921     if (fib_path_is_permanent_drop(path))
1922     {
1923         dpo_copy(&path->fp_dpo, drop_dpo_get(path->fp_nh_proto));
1924         path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
1925         return (fib_path_is_resolved(path_index));
1926     }
1927
1928     switch (path->fp_type)
1929     {
1930     case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
1931         fib_path_attached_next_hop_set(path);
1932         break;
1933     case FIB_PATH_TYPE_ATTACHED:
1934     {
1935         dpo_id_t tmp = DPO_INVALID;
1936
1937         /*
1938          * path->attached.fp_interface
1939          */
1940         if (!vnet_sw_interface_is_up(vnet_get_main(),
1941                                      path->attached.fp_interface))
1942         {
1943             path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
1944         }
1945         fib_path_attached_get_adj(path,
1946                                   dpo_proto_to_link(path->fp_nh_proto),
1947                                   &tmp);
1948
1949         /*
1950          * re-fetch after possible mem realloc
1951          */
1952         path = fib_path_get(path_index);
1953         dpo_copy(&path->fp_dpo, &tmp);
1954
1955         /*
1956          * become a child of the adjacency so we receive updates
1957          * when the interface state changes
1958          */
1959         if (dpo_is_adj(&path->fp_dpo))
1960         {
1961             path->fp_sibling = adj_child_add(path->fp_dpo.dpoi_index,
1962                                              FIB_NODE_TYPE_PATH,
1963                                              fib_path_get_index(path));
1964         }
1965         dpo_reset(&tmp);
1966         break;
1967     }
1968     case FIB_PATH_TYPE_RECURSIVE:
1969     {
1970         /*
1971          * Create a RR source entry in the table for the address
1972          * that this path recurses through.
1973          * This resolve action is recursive, hence we may create
1974          * more paths in the process. more creates mean maybe realloc
1975          * of this path.
1976          */
1977         fib_node_index_t fei;
1978         fib_prefix_t pfx;
1979
1980         ASSERT(FIB_NODE_INDEX_INVALID == path->fp_via_fib);
1981
1982         if (DPO_PROTO_MPLS == path->fp_nh_proto)
1983         {
1984             fib_prefix_from_mpls_label(path->recursive.fp_nh.fp_local_label,
1985                                        path->recursive.fp_nh.fp_eos,
1986                                        &pfx);
1987         }
1988         else
1989         {
1990             fib_prefix_from_ip46_addr(&path->recursive.fp_nh.fp_ip, &pfx);
1991         }
1992
1993         fib_table_lock(path->recursive.fp_tbl_id,
1994                        dpo_proto_to_fib(path->fp_nh_proto),
1995                        FIB_SOURCE_RR);
1996         fei = fib_table_entry_special_add(path->recursive.fp_tbl_id,
1997                                           &pfx,
1998                                           FIB_SOURCE_RR,
1999                                           FIB_ENTRY_FLAG_NONE);
2000
2001         path = fib_path_get(path_index);
2002         path->fp_via_fib = fei;
2003
2004         /*
2005          * become a dependent child of the entry so the path is
2006          * informed when the forwarding for the entry changes.
2007          */
2008         path->fp_sibling = fib_entry_child_add(path->fp_via_fib,
2009                                                FIB_NODE_TYPE_PATH,
2010                                                fib_path_get_index(path));
2011
2012         /*
2013          * create and configure the IP DPO
2014          */
2015         fib_path_recursive_adj_update(
2016             path,
2017             fib_path_to_chain_type(path),
2018             &path->fp_dpo);
2019
2020         break;
2021     }
2022     case FIB_PATH_TYPE_BIER_FMASK:
2023     {
2024         /*
2025          * become a dependent child of the entry so the path is
2026          * informed when the forwarding for the entry changes.
2027          */
2028         path->fp_sibling = bier_fmask_child_add(path->bier_fmask.fp_bier_fmask,
2029                                                 FIB_NODE_TYPE_PATH,
2030                                                 fib_path_get_index(path));
2031
2032         path->fp_via_bier_fmask = path->bier_fmask.fp_bier_fmask;
2033         fib_path_bier_fmask_update(path, &path->fp_dpo);
2034
2035         break;
2036     }
2037     case FIB_PATH_TYPE_BIER_IMP:
2038         bier_imp_lock(path->bier_imp.fp_bier_imp);
2039         bier_imp_contribute_forwarding(path->bier_imp.fp_bier_imp,
2040                                        DPO_PROTO_IP4,
2041                                        &path->fp_dpo);
2042         break;
2043     case FIB_PATH_TYPE_BIER_TABLE:
2044     {
2045         /*
2046          * Find/create the BIER table to link to
2047          */
2048         ASSERT(FIB_NODE_INDEX_INVALID == path->fp_via_bier_tbl);
2049
2050         path->fp_via_bier_tbl =
2051             bier_table_ecmp_create_and_lock(&path->bier_table.fp_bier_tbl);
2052
2053         bier_table_contribute_forwarding(path->fp_via_bier_tbl,
2054                                          &path->fp_dpo);
2055         break;
2056     }
2057     case FIB_PATH_TYPE_SPECIAL:
2058         if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_ICMP_PROHIBIT)
2059         {
2060             ip_null_dpo_add_and_lock (path->fp_nh_proto,
2061                                       IP_NULL_ACTION_SEND_ICMP_PROHIBIT,
2062                                       &path->fp_dpo);
2063         }
2064         else if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_ICMP_UNREACH)
2065         {
2066             ip_null_dpo_add_and_lock (path->fp_nh_proto,
2067                                       IP_NULL_ACTION_SEND_ICMP_UNREACH,
2068                                       &path->fp_dpo);
2069         }
2070         else if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_CLASSIFY)
2071         {
2072             dpo_set (&path->fp_dpo, DPO_CLASSIFY,
2073                      path->fp_nh_proto,
2074                      classify_dpo_create (path->fp_nh_proto,
2075                                           path->classify.fp_classify_table_id));
2076         }
2077         else
2078         {
2079             /*
2080              * Resolve via the drop
2081              */
2082             dpo_copy(&path->fp_dpo, drop_dpo_get(path->fp_nh_proto));
2083         }
2084         break;
2085     case FIB_PATH_TYPE_DEAG:
2086     {
2087         if (DPO_PROTO_BIER == path->fp_nh_proto)
2088         {
2089             bier_disp_table_contribute_forwarding(path->deag.fp_tbl_id,
2090                                                   &path->fp_dpo);
2091         }
2092         else
2093         {
2094             /*
2095              * Resolve via a lookup DPO.
2096              * FIXME. control plane should add routes with a table ID
2097              */
2098             lookup_input_t input;
2099             lookup_cast_t cast;
2100
2101             cast = (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_RPF_ID ?
2102                     LOOKUP_MULTICAST :
2103                     LOOKUP_UNICAST);
2104             input = (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_DEAG_SRC ?
2105                      LOOKUP_INPUT_SRC_ADDR :
2106                      LOOKUP_INPUT_DST_ADDR);
2107
2108             lookup_dpo_add_or_lock_w_fib_index(path->deag.fp_tbl_id,
2109                                                path->fp_nh_proto,
2110                                                cast,
2111                                                input,
2112                                                LOOKUP_TABLE_FROM_CONFIG,
2113                                                &path->fp_dpo);
2114         }
2115         break;
2116     }
2117     case FIB_PATH_TYPE_DVR:
2118         dvr_dpo_add_or_lock(path->dvr.fp_interface,
2119                             path->fp_nh_proto,
2120                             &path->fp_dpo);
2121         break;
2122     case FIB_PATH_TYPE_RECEIVE:
2123         /*
2124          * Resolve via a receive DPO.
2125          */
2126         receive_dpo_add_or_lock(path->fp_nh_proto,
2127                                 path->receive.fp_interface,
2128                                 &path->receive.fp_addr,
2129                                 &path->fp_dpo);
2130         break;
2131     case FIB_PATH_TYPE_UDP_ENCAP:
2132         udp_encap_lock(path->udp_encap.fp_udp_encap_id);
2133         udp_encap_contribute_forwarding(path->udp_encap.fp_udp_encap_id,
2134                                         path->fp_nh_proto,
2135                                         &path->fp_dpo);
2136         break;
2137     case FIB_PATH_TYPE_INTF_RX: {
2138         /*
2139          * Resolve via a receive DPO.
2140          */
2141         interface_rx_dpo_add_or_lock(path->fp_nh_proto,
2142                                      path->intf_rx.fp_interface,
2143                                      &path->fp_dpo);
2144         break;
2145     }
2146     case FIB_PATH_TYPE_EXCLUSIVE:
2147         /*
2148          * Resolve via the user provided DPO
2149          */
2150         dpo_copy(&path->fp_dpo, &path->exclusive.fp_ex_dpo);
2151         break;
2152     }
2153
2154     return (fib_path_is_resolved(path_index));
2155 }
2156
2157 u32
2158 fib_path_get_resolving_interface (fib_node_index_t path_index)
2159 {
2160     fib_path_t *path;
2161
2162     path = fib_path_get(path_index);
2163
2164     switch (path->fp_type)
2165     {
2166     case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
2167         return (path->attached_next_hop.fp_interface);
2168     case FIB_PATH_TYPE_ATTACHED:
2169         return (path->attached.fp_interface);
2170     case FIB_PATH_TYPE_RECEIVE:
2171         return (path->receive.fp_interface);
2172     case FIB_PATH_TYPE_RECURSIVE:
2173         if (fib_path_is_resolved(path_index))
2174         {
2175             return (fib_entry_get_resolving_interface(path->fp_via_fib));
2176         }
2177         break;
2178     case FIB_PATH_TYPE_DVR:
2179         return (path->dvr.fp_interface);
2180     case FIB_PATH_TYPE_INTF_RX:
2181     case FIB_PATH_TYPE_UDP_ENCAP:
2182     case FIB_PATH_TYPE_SPECIAL:
2183     case FIB_PATH_TYPE_DEAG:
2184     case FIB_PATH_TYPE_EXCLUSIVE:
2185     case FIB_PATH_TYPE_BIER_FMASK:
2186     case FIB_PATH_TYPE_BIER_TABLE:
2187     case FIB_PATH_TYPE_BIER_IMP:
2188         break;
2189     }
2190     return (dpo_get_urpf(&path->fp_dpo));
2191 }
2192
2193 index_t
2194 fib_path_get_resolving_index (fib_node_index_t path_index)
2195 {
2196     fib_path_t *path;
2197
2198     path = fib_path_get(path_index);
2199
2200     switch (path->fp_type)
2201     {
2202     case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
2203     case FIB_PATH_TYPE_ATTACHED:
2204     case FIB_PATH_TYPE_RECEIVE:
2205     case FIB_PATH_TYPE_INTF_RX:
2206     case FIB_PATH_TYPE_SPECIAL:
2207     case FIB_PATH_TYPE_DEAG:
2208     case FIB_PATH_TYPE_DVR:
2209     case FIB_PATH_TYPE_EXCLUSIVE:
2210         break;
2211     case FIB_PATH_TYPE_UDP_ENCAP:
2212         return (path->udp_encap.fp_udp_encap_id);
2213     case FIB_PATH_TYPE_RECURSIVE:
2214         return (path->fp_via_fib);
2215     case FIB_PATH_TYPE_BIER_FMASK:
2216         return (path->bier_fmask.fp_bier_fmask);
2217    case FIB_PATH_TYPE_BIER_TABLE:
2218        return (path->fp_via_bier_tbl);
2219    case FIB_PATH_TYPE_BIER_IMP:
2220        return (path->bier_imp.fp_bier_imp);
2221     }
2222     return (~0);
2223 }
2224
2225 adj_index_t
2226 fib_path_get_adj (fib_node_index_t path_index)
2227 {
2228     fib_path_t *path;
2229
2230     path = fib_path_get(path_index);
2231
2232     if (dpo_is_adj(&path->fp_dpo))
2233     {
2234         return (path->fp_dpo.dpoi_index);
2235     }
2236     return (ADJ_INDEX_INVALID);
2237 }
2238
2239 u16
2240 fib_path_get_weight (fib_node_index_t path_index)
2241 {
2242     fib_path_t *path;
2243
2244     path = fib_path_get(path_index);
2245
2246     ASSERT(path);
2247
2248     return (path->fp_weight);
2249 }
2250
2251 u16
2252 fib_path_get_preference (fib_node_index_t path_index)
2253 {
2254     fib_path_t *path;
2255
2256     path = fib_path_get(path_index);
2257
2258     ASSERT(path);
2259
2260     return (path->fp_preference);
2261 }
2262
2263 u32
2264 fib_path_get_rpf_id (fib_node_index_t path_index)
2265 {
2266     fib_path_t *path;
2267
2268     path = fib_path_get(path_index);
2269
2270     ASSERT(path);
2271
2272     if (FIB_PATH_CFG_FLAG_RPF_ID & path->fp_cfg_flags)
2273     {
2274         return (path->deag.fp_rpf_id);
2275     }
2276
2277     return (~0);
2278 }
2279
2280 /**
2281  * @brief Contribute the path's adjacency to the list passed.
2282  * By calling this function over all paths, recursively, a child
2283  * can construct its full set of forwarding adjacencies, and hence its
2284  * uRPF list.
2285  */
2286 void
2287 fib_path_contribute_urpf (fib_node_index_t path_index,
2288                           index_t urpf)
2289 {
2290     fib_path_t *path;
2291
2292     path = fib_path_get(path_index);
2293
2294     /*
2295      * resolved and unresolved paths contribute to the RPF list.
2296      */
2297     switch (path->fp_type)
2298     {
2299     case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
2300         fib_urpf_list_append(urpf, path->attached_next_hop.fp_interface);
2301         break;
2302
2303     case FIB_PATH_TYPE_ATTACHED:
2304         fib_urpf_list_append(urpf, path->attached.fp_interface);
2305         break;
2306
2307     case FIB_PATH_TYPE_RECURSIVE:
2308         if (FIB_NODE_INDEX_INVALID != path->fp_via_fib &&
2309             !fib_path_is_looped(path_index))
2310         {
2311             /*
2312              * there's unresolved due to constraints, and there's unresolved
2313              * due to ain't got no via. can't do nowt w'out via.
2314              */
2315             fib_entry_contribute_urpf(path->fp_via_fib, urpf);
2316         }
2317         break;
2318
2319     case FIB_PATH_TYPE_EXCLUSIVE:
2320     case FIB_PATH_TYPE_SPECIAL:
2321     {
2322         /*
2323          * these path types may link to an adj, if that's what
2324          * the clinet gave
2325          */
2326         u32 rpf_sw_if_index;
2327
2328         rpf_sw_if_index = dpo_get_urpf(&path->fp_dpo);
2329
2330         if (~0 != rpf_sw_if_index)
2331         {
2332             fib_urpf_list_append(urpf, rpf_sw_if_index);
2333         }
2334         break;
2335     }
2336     case FIB_PATH_TYPE_DVR:
2337         fib_urpf_list_append(urpf, path->dvr.fp_interface);
2338         break;
2339     case FIB_PATH_TYPE_UDP_ENCAP:
2340         fib_urpf_list_append(urpf, path->udp_encap.fp_udp_encap_id);
2341         break;
2342     case FIB_PATH_TYPE_DEAG:
2343     case FIB_PATH_TYPE_RECEIVE:
2344     case FIB_PATH_TYPE_INTF_RX:
2345     case FIB_PATH_TYPE_BIER_FMASK:
2346     case FIB_PATH_TYPE_BIER_TABLE:
2347     case FIB_PATH_TYPE_BIER_IMP:
2348         /*
2349          * these path types don't link to an adj
2350          */
2351         break;
2352     }
2353 }
2354
2355 void
2356 fib_path_stack_mpls_disp (fib_node_index_t path_index,
2357                           dpo_proto_t payload_proto,
2358                           fib_mpls_lsp_mode_t mode,
2359                           dpo_id_t *dpo)
2360 {
2361     fib_path_t *path;
2362
2363     path = fib_path_get(path_index);
2364
2365     ASSERT(path);
2366
2367     switch (path->fp_type)
2368     {
2369     case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
2370     {
2371         dpo_id_t tmp = DPO_INVALID;
2372
2373         dpo_copy(&tmp, dpo);
2374
2375         mpls_disp_dpo_create(payload_proto, ~0, mode, &tmp, dpo);
2376         dpo_reset(&tmp);
2377         break;
2378     }
2379     case FIB_PATH_TYPE_DEAG:
2380     {
2381         dpo_id_t tmp = DPO_INVALID;
2382
2383         dpo_copy(&tmp, dpo);
2384
2385         mpls_disp_dpo_create(payload_proto,
2386                              path->deag.fp_rpf_id,
2387                              mode, &tmp, dpo);
2388         dpo_reset(&tmp);
2389         break;
2390     }
2391     case FIB_PATH_TYPE_RECEIVE:
2392     case FIB_PATH_TYPE_ATTACHED:
2393     case FIB_PATH_TYPE_RECURSIVE:
2394     case FIB_PATH_TYPE_INTF_RX:
2395     case FIB_PATH_TYPE_UDP_ENCAP:
2396     case FIB_PATH_TYPE_EXCLUSIVE:
2397     case FIB_PATH_TYPE_SPECIAL:
2398     case FIB_PATH_TYPE_BIER_FMASK:
2399     case FIB_PATH_TYPE_BIER_TABLE:
2400     case FIB_PATH_TYPE_BIER_IMP:
2401     case FIB_PATH_TYPE_DVR:
2402         break;
2403     }
2404
2405     if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_POP_PW_CW)
2406     {
2407         dpo_id_t tmp = DPO_INVALID;
2408
2409         dpo_copy(&tmp, dpo);
2410
2411         pw_cw_dpo_create(&tmp, dpo);
2412         dpo_reset(&tmp);
2413     }
2414 }
2415
2416 void
2417 fib_path_contribute_forwarding (fib_node_index_t path_index,
2418                                 fib_forward_chain_type_t fct,
2419                                 dpo_id_t *dpo)
2420 {
2421     fib_path_t *path;
2422
2423     path = fib_path_get(path_index);
2424
2425     ASSERT(path);
2426     ASSERT(FIB_FORW_CHAIN_TYPE_MPLS_EOS != fct);
2427
2428     /*
2429      * The DPO stored in the path was created when the path was resolved.
2430      * This then represents the path's 'native' protocol; IP.
2431      * For all others will need to go find something else.
2432      */
2433     if (fib_path_to_chain_type(path) == fct)
2434     {
2435         dpo_copy(dpo, &path->fp_dpo);
2436     }
2437     else
2438     {
2439         switch (path->fp_type)
2440         {
2441         case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
2442             switch (fct)
2443             {
2444             case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
2445             case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
2446             case FIB_FORW_CHAIN_TYPE_MPLS_EOS:
2447             case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
2448             case FIB_FORW_CHAIN_TYPE_ETHERNET:
2449             case FIB_FORW_CHAIN_TYPE_NSH:
2450             case FIB_FORW_CHAIN_TYPE_MCAST_IP4:
2451             case FIB_FORW_CHAIN_TYPE_MCAST_IP6:
2452                 {
2453                     dpo_id_t tmp = DPO_INVALID;
2454                     dpo_copy (&tmp, dpo);
2455                     path = fib_path_attached_next_hop_get_adj(
2456                            path,
2457                            fib_forw_chain_type_to_link_type(fct),
2458                            &tmp);
2459                     dpo_copy (dpo, &tmp);
2460                     dpo_reset(&tmp);
2461                     break;
2462                 }
2463             case FIB_FORW_CHAIN_TYPE_BIER:
2464                 break;
2465             }
2466             break;
2467         case FIB_PATH_TYPE_RECURSIVE:
2468             switch (fct)
2469             {
2470             case FIB_FORW_CHAIN_TYPE_MPLS_EOS:
2471             case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
2472             case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
2473             case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
2474             case FIB_FORW_CHAIN_TYPE_MCAST_IP4:
2475             case FIB_FORW_CHAIN_TYPE_MCAST_IP6:
2476             case FIB_FORW_CHAIN_TYPE_BIER:
2477                 fib_path_recursive_adj_update(path, fct, dpo);
2478                 break;
2479             case FIB_FORW_CHAIN_TYPE_ETHERNET:
2480             case FIB_FORW_CHAIN_TYPE_NSH:
2481                 ASSERT(0);
2482                 break;
2483             }
2484             break;
2485         case FIB_PATH_TYPE_BIER_TABLE:
2486             switch (fct)
2487             {
2488             case FIB_FORW_CHAIN_TYPE_BIER:
2489                 bier_table_contribute_forwarding(path->fp_via_bier_tbl, dpo);
2490                 break;
2491             case FIB_FORW_CHAIN_TYPE_MPLS_EOS:
2492             case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
2493             case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
2494             case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
2495             case FIB_FORW_CHAIN_TYPE_MCAST_IP4:
2496             case FIB_FORW_CHAIN_TYPE_MCAST_IP6:
2497             case FIB_FORW_CHAIN_TYPE_ETHERNET:
2498             case FIB_FORW_CHAIN_TYPE_NSH:
2499                 ASSERT(0);
2500                 break;
2501             }
2502             break;
2503         case FIB_PATH_TYPE_BIER_FMASK:
2504             switch (fct)
2505             {
2506             case FIB_FORW_CHAIN_TYPE_BIER:
2507                 fib_path_bier_fmask_update(path, dpo);
2508                 break;
2509             case FIB_FORW_CHAIN_TYPE_MPLS_EOS:
2510             case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
2511             case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
2512             case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
2513             case FIB_FORW_CHAIN_TYPE_MCAST_IP4:
2514             case FIB_FORW_CHAIN_TYPE_MCAST_IP6:
2515             case FIB_FORW_CHAIN_TYPE_ETHERNET:
2516             case FIB_FORW_CHAIN_TYPE_NSH:
2517                 ASSERT(0);
2518                 break;
2519             }
2520             break;
2521         case FIB_PATH_TYPE_BIER_IMP:
2522             bier_imp_contribute_forwarding(path->bier_imp.fp_bier_imp,
2523                                            fib_forw_chain_type_to_dpo_proto(fct),
2524                                            dpo);
2525             break;
2526         case FIB_PATH_TYPE_DEAG:
2527             switch (fct)
2528             {
2529             case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
2530                 lookup_dpo_add_or_lock_w_table_id(MPLS_FIB_DEFAULT_TABLE_ID,
2531                                                   DPO_PROTO_MPLS,
2532                                                   LOOKUP_UNICAST,
2533                                                   LOOKUP_INPUT_DST_ADDR,
2534                                                   LOOKUP_TABLE_FROM_CONFIG,
2535                                                   dpo);
2536                 break;
2537             case FIB_FORW_CHAIN_TYPE_MPLS_EOS:
2538             case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
2539             case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
2540             case FIB_FORW_CHAIN_TYPE_MCAST_IP4:
2541             case FIB_FORW_CHAIN_TYPE_MCAST_IP6:
2542                 dpo_copy(dpo, &path->fp_dpo);
2543                 break;
2544             case FIB_FORW_CHAIN_TYPE_BIER:
2545                 break;
2546             case FIB_FORW_CHAIN_TYPE_ETHERNET:
2547             case FIB_FORW_CHAIN_TYPE_NSH:
2548                 ASSERT(0);
2549                 break;
2550             }
2551             break;
2552         case FIB_PATH_TYPE_EXCLUSIVE:
2553             dpo_copy(dpo, &path->exclusive.fp_ex_dpo);
2554             break;
2555         case FIB_PATH_TYPE_ATTACHED:
2556             switch (fct)
2557             {
2558             case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
2559             case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
2560             case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
2561             case FIB_FORW_CHAIN_TYPE_MPLS_EOS:
2562             case FIB_FORW_CHAIN_TYPE_ETHERNET:
2563             case FIB_FORW_CHAIN_TYPE_NSH:
2564             case FIB_FORW_CHAIN_TYPE_BIER:
2565                 fib_path_attached_get_adj(path,
2566                                           fib_forw_chain_type_to_link_type(fct),
2567                                           dpo);
2568                 break;
2569             case FIB_FORW_CHAIN_TYPE_MCAST_IP4:
2570             case FIB_FORW_CHAIN_TYPE_MCAST_IP6:
2571                 {
2572                     adj_index_t ai;
2573
2574                     /*
2575                      * Create the adj needed for sending IP multicast traffic
2576                      */
2577                     if (vnet_sw_interface_is_p2p(vnet_get_main(),
2578                                                  path->attached.fp_interface))
2579                     {
2580                         /*
2581                          * point-2-point interfaces do not require a glean, since
2582                          * there is nothing to ARP. Install a rewrite/nbr adj instead
2583                          */
2584                         ai = adj_nbr_add_or_lock(dpo_proto_to_fib(path->fp_nh_proto),
2585                                                  fib_forw_chain_type_to_link_type(fct),
2586                                                  &zero_addr,
2587                                                  path->attached.fp_interface);
2588                     }
2589                     else
2590                     {
2591                         ai = adj_mcast_add_or_lock(dpo_proto_to_fib(path->fp_nh_proto),
2592                                                    fib_forw_chain_type_to_link_type(fct),
2593                                                    path->attached.fp_interface);
2594                     }
2595                     dpo_set(dpo, DPO_ADJACENCY,
2596                             fib_forw_chain_type_to_dpo_proto(fct),
2597                             ai);
2598                     adj_unlock(ai);
2599                 }
2600                 break;
2601             }
2602             break;
2603         case FIB_PATH_TYPE_INTF_RX:
2604             /*
2605              * Create the adj needed for sending IP multicast traffic
2606              */
2607             interface_rx_dpo_add_or_lock(fib_forw_chain_type_to_dpo_proto(fct),
2608                                          path->attached.fp_interface,
2609                                          dpo);
2610             break;
2611         case FIB_PATH_TYPE_UDP_ENCAP:
2612             udp_encap_contribute_forwarding(path->udp_encap.fp_udp_encap_id,
2613                                             path->fp_nh_proto,
2614                                             dpo);
2615             break;
2616         case FIB_PATH_TYPE_RECEIVE:
2617         case FIB_PATH_TYPE_SPECIAL:
2618         case FIB_PATH_TYPE_DVR:
2619             dpo_copy(dpo, &path->fp_dpo);
2620             break;
2621         }
2622     }
2623 }
2624
2625 load_balance_path_t *
2626 fib_path_append_nh_for_multipath_hash (fib_node_index_t path_index,
2627                                        fib_forward_chain_type_t fct,
2628                                        load_balance_path_t *hash_key)
2629 {
2630     load_balance_path_t *mnh;
2631     fib_path_t *path;
2632
2633     path = fib_path_get(path_index);
2634
2635     ASSERT(path);
2636
2637     vec_add2(hash_key, mnh, 1);
2638
2639     mnh->path_weight = path->fp_weight;
2640     mnh->path_index = path_index;
2641
2642     if (fib_path_is_resolved(path_index))
2643     {
2644         fib_path_contribute_forwarding(path_index, fct, &mnh->path_dpo);
2645     }
2646     else
2647     {
2648         dpo_copy(&mnh->path_dpo,
2649                  drop_dpo_get(fib_forw_chain_type_to_dpo_proto(fct)));
2650     }
2651     return (hash_key);
2652 }
2653
2654 int
2655 fib_path_is_recursive_constrained (fib_node_index_t path_index)
2656 {
2657     fib_path_t *path;
2658
2659     path = fib_path_get(path_index);
2660
2661     return ((FIB_PATH_TYPE_RECURSIVE == path->fp_type) &&
2662             ((path->fp_cfg_flags & FIB_PATH_CFG_FLAG_RESOLVE_ATTACHED) ||
2663              (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_RESOLVE_HOST)));
2664 }
2665
2666 int
2667 fib_path_is_exclusive (fib_node_index_t path_index)
2668 {
2669     fib_path_t *path;
2670
2671     path = fib_path_get(path_index);
2672
2673     return (FIB_PATH_TYPE_EXCLUSIVE == path->fp_type);
2674 }
2675
2676 int
2677 fib_path_is_deag (fib_node_index_t path_index)
2678 {
2679     fib_path_t *path;
2680
2681     path = fib_path_get(path_index);
2682
2683     return (FIB_PATH_TYPE_DEAG == path->fp_type);
2684 }
2685
2686 int
2687 fib_path_is_resolved (fib_node_index_t path_index)
2688 {
2689     fib_path_t *path;
2690
2691     path = fib_path_get(path_index);
2692
2693     return (dpo_id_is_valid(&path->fp_dpo) &&
2694             (path->fp_oper_flags & FIB_PATH_OPER_FLAG_RESOLVED) &&
2695             !fib_path_is_looped(path_index) &&
2696             !fib_path_is_permanent_drop(path));
2697 }
2698
2699 int
2700 fib_path_is_looped (fib_node_index_t path_index)
2701 {
2702     fib_path_t *path;
2703
2704     path = fib_path_get(path_index);
2705
2706     return (path->fp_oper_flags & FIB_PATH_OPER_FLAG_RECURSIVE_LOOP);
2707 }
2708
2709 fib_path_list_walk_rc_t
2710 fib_path_encode (fib_node_index_t path_list_index,
2711                  fib_node_index_t path_index,
2712                  const fib_path_ext_t *path_ext,
2713                  void *args)
2714 {
2715     fib_path_encode_ctx_t *ctx = args;
2716     fib_route_path_t *rpath;
2717     fib_path_t *path;
2718
2719     path = fib_path_get(path_index);
2720     if (!path)
2721       return (FIB_PATH_LIST_WALK_CONTINUE);
2722
2723     vec_add2(ctx->rpaths, rpath, 1);
2724     rpath->frp_weight = path->fp_weight;
2725     rpath->frp_preference = path->fp_preference;
2726     rpath->frp_proto = path->fp_nh_proto;
2727     rpath->frp_sw_if_index = ~0;
2728     rpath->frp_fib_index = 0;
2729
2730     switch (path->fp_type)
2731     {
2732       case FIB_PATH_TYPE_RECEIVE:
2733         rpath->frp_addr = path->receive.fp_addr;
2734         rpath->frp_sw_if_index = path->receive.fp_interface;
2735         rpath->frp_flags |= FIB_ROUTE_PATH_LOCAL;
2736         break;
2737       case FIB_PATH_TYPE_ATTACHED:
2738         rpath->frp_sw_if_index = path->attached.fp_interface;
2739         break;
2740       case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
2741         rpath->frp_sw_if_index = path->attached_next_hop.fp_interface;
2742         rpath->frp_addr = path->attached_next_hop.fp_nh;
2743         break;
2744       case FIB_PATH_TYPE_BIER_FMASK:
2745         rpath->frp_bier_fmask = path->bier_fmask.fp_bier_fmask;
2746         break;
2747       case FIB_PATH_TYPE_SPECIAL:
2748         break;
2749       case FIB_PATH_TYPE_DEAG:
2750         rpath->frp_fib_index = path->deag.fp_tbl_id;
2751         if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_RPF_ID)
2752         {
2753             rpath->frp_flags |= FIB_ROUTE_PATH_RPF_ID;
2754         }
2755         break;
2756       case FIB_PATH_TYPE_RECURSIVE:
2757         rpath->frp_addr = path->recursive.fp_nh.fp_ip;
2758         rpath->frp_fib_index = path->recursive.fp_tbl_id;
2759         break;
2760       case FIB_PATH_TYPE_DVR:
2761           rpath->frp_sw_if_index = path->dvr.fp_interface;
2762           rpath->frp_flags |= FIB_ROUTE_PATH_DVR;
2763           break;
2764       case FIB_PATH_TYPE_UDP_ENCAP:
2765           rpath->frp_udp_encap_id = path->udp_encap.fp_udp_encap_id;
2766           rpath->frp_flags |= FIB_ROUTE_PATH_UDP_ENCAP;
2767           break;
2768       case FIB_PATH_TYPE_INTF_RX:
2769           rpath->frp_sw_if_index = path->receive.fp_interface;
2770           rpath->frp_flags |= FIB_ROUTE_PATH_INTF_RX;
2771           break;
2772       case FIB_PATH_TYPE_EXCLUSIVE:
2773         rpath->frp_flags |= FIB_ROUTE_PATH_EXCLUSIVE;
2774       default:
2775         break;
2776     }
2777
2778     if (path_ext && path_ext->fpe_type == FIB_PATH_EXT_MPLS)
2779     {
2780         rpath->frp_label_stack = path_ext->fpe_path.frp_label_stack;
2781     }
2782
2783     if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_DROP)
2784         rpath->frp_flags |= FIB_ROUTE_PATH_DROP;
2785     if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_ICMP_UNREACH)
2786         rpath->frp_flags |= FIB_ROUTE_PATH_ICMP_UNREACH;
2787     if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_ICMP_PROHIBIT)
2788         rpath->frp_flags |= FIB_ROUTE_PATH_ICMP_PROHIBIT;
2789
2790     return (FIB_PATH_LIST_WALK_CONTINUE);
2791 }
2792
2793 dpo_proto_t
2794 fib_path_get_proto (fib_node_index_t path_index)
2795 {
2796     fib_path_t *path;
2797
2798     path = fib_path_get(path_index);
2799
2800     return (path->fp_nh_proto);
2801 }
2802
2803 void
2804 fib_path_module_init (void)
2805 {
2806     fib_node_register_type (FIB_NODE_TYPE_PATH, &fib_path_vft);
2807     fib_path_logger = vlib_log_register_class ("fib", "path");
2808 }
2809
2810 static clib_error_t *
2811 show_fib_path_command (vlib_main_t * vm,
2812                         unformat_input_t * input,
2813                         vlib_cli_command_t * cmd)
2814 {
2815     fib_node_index_t pi;
2816     fib_path_t *path;
2817
2818     if (unformat (input, "%d", &pi))
2819     {
2820         /*
2821          * show one in detail
2822          */
2823         if (!pool_is_free_index(fib_path_pool, pi))
2824         {
2825             path = fib_path_get(pi);
2826             u8 *s = format(NULL, "%U", format_fib_path, pi, 1,
2827                            FIB_PATH_FORMAT_FLAGS_NONE);
2828             s = format(s, "\n  children:");
2829             s = fib_node_children_format(path->fp_node.fn_children, s);
2830             vlib_cli_output (vm, "%v", s);
2831             vec_free(s);
2832         }
2833         else
2834         {
2835             vlib_cli_output (vm, "path %d invalid", pi);
2836         }
2837     }
2838     else
2839     {
2840         vlib_cli_output (vm, "FIB Paths");
2841         pool_foreach_index (pi, fib_path_pool)
2842          {
2843             vlib_cli_output (vm, "%U", format_fib_path, pi, 0,
2844                              FIB_PATH_FORMAT_FLAGS_NONE);
2845         }
2846     }
2847
2848     return (NULL);
2849 }
2850
2851 VLIB_CLI_COMMAND (show_fib_path, static) = {
2852   .path = "show fib paths",
2853   .function = show_fib_path_command,
2854   .short_help = "show fib paths",
2855 };