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         if (FIB_NODE_BW_REASON_FLAG_INTERFACE_BIND & ctx->fnbw_reason)
1165         {
1166             /* bind walks should appear here and pass silently up to
1167              * to the fib_entry */
1168         }
1169         break;
1170     case FIB_PATH_TYPE_UDP_ENCAP:
1171     {
1172         dpo_id_t via_dpo = DPO_INVALID;
1173
1174         /*
1175          * hope for the best - clear if restrictions apply.
1176          */
1177         path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RESOLVED;
1178
1179         udp_encap_contribute_forwarding(path->udp_encap.fp_udp_encap_id,
1180                                         path->fp_nh_proto,
1181                                         &via_dpo);
1182         /*
1183          * If this path is contributing a drop, then it's not resolved
1184          */
1185         if (dpo_is_drop(&via_dpo) || load_balance_is_drop(&via_dpo))
1186         {
1187             path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
1188         }
1189
1190         /*
1191          * update the path's contributed DPO
1192          */
1193         dpo_copy(&path->fp_dpo, &via_dpo);
1194         dpo_reset(&via_dpo);
1195         break;
1196     }
1197     case FIB_PATH_TYPE_INTF_RX:
1198         ASSERT(0);
1199     case FIB_PATH_TYPE_DEAG:
1200         /*
1201          * FIXME When VRF delete is allowed this will need a poke.
1202          */
1203     case FIB_PATH_TYPE_SPECIAL:
1204     case FIB_PATH_TYPE_RECEIVE:
1205     case FIB_PATH_TYPE_EXCLUSIVE:
1206     case FIB_PATH_TYPE_BIER_TABLE:
1207     case FIB_PATH_TYPE_BIER_IMP:
1208         /*
1209          * these path types have no parents. so to be
1210          * walked from one is unexpected.
1211          */
1212         ASSERT(0);
1213         break;
1214     }
1215
1216     /*
1217      * propagate the backwalk further to the path-list
1218      */
1219     fib_path_list_back_walk(path->fp_pl_index, ctx);
1220
1221     return (FIB_NODE_BACK_WALK_CONTINUE);
1222 }
1223
1224 static void
1225 fib_path_memory_show (void)
1226 {
1227     fib_show_memory_usage("Path",
1228                           pool_elts(fib_path_pool),
1229                           pool_len(fib_path_pool),
1230                           sizeof(fib_path_t));
1231 }
1232
1233 /*
1234  * The FIB path's graph node virtual function table
1235  */
1236 static const fib_node_vft_t fib_path_vft = {
1237     .fnv_get = fib_path_get_node,
1238     .fnv_last_lock = fib_path_last_lock_gone,
1239     .fnv_back_walk = fib_path_back_walk_notify,
1240     .fnv_mem_show = fib_path_memory_show,
1241 };
1242
1243 static fib_path_cfg_flags_t
1244 fib_path_route_flags_to_cfg_flags (const fib_route_path_t *rpath)
1245 {
1246     fib_path_cfg_flags_t cfg_flags = FIB_PATH_CFG_FLAG_NONE;
1247
1248     if (rpath->frp_flags & FIB_ROUTE_PATH_POP_PW_CW)
1249         cfg_flags |= FIB_PATH_CFG_FLAG_POP_PW_CW;
1250     if (rpath->frp_flags & FIB_ROUTE_PATH_RESOLVE_VIA_HOST)
1251         cfg_flags |= FIB_PATH_CFG_FLAG_RESOLVE_HOST;
1252     if (rpath->frp_flags & FIB_ROUTE_PATH_RESOLVE_VIA_ATTACHED)
1253         cfg_flags |= FIB_PATH_CFG_FLAG_RESOLVE_ATTACHED;
1254     if (rpath->frp_flags & FIB_ROUTE_PATH_LOCAL)
1255         cfg_flags |= FIB_PATH_CFG_FLAG_LOCAL;
1256     if (rpath->frp_flags & FIB_ROUTE_PATH_ATTACHED)
1257         cfg_flags |= FIB_PATH_CFG_FLAG_ATTACHED;
1258     if (rpath->frp_flags & FIB_ROUTE_PATH_INTF_RX)
1259         cfg_flags |= FIB_PATH_CFG_FLAG_INTF_RX;
1260     if (rpath->frp_flags & FIB_ROUTE_PATH_RPF_ID)
1261         cfg_flags |= FIB_PATH_CFG_FLAG_RPF_ID;
1262     if (rpath->frp_flags & FIB_ROUTE_PATH_EXCLUSIVE)
1263         cfg_flags |= FIB_PATH_CFG_FLAG_EXCLUSIVE;
1264     if (rpath->frp_flags & FIB_ROUTE_PATH_DROP)
1265         cfg_flags |= FIB_PATH_CFG_FLAG_DROP;
1266     if (rpath->frp_flags & FIB_ROUTE_PATH_SOURCE_LOOKUP)
1267         cfg_flags |= FIB_PATH_CFG_FLAG_DEAG_SRC;
1268     if (rpath->frp_flags & FIB_ROUTE_PATH_ICMP_UNREACH)
1269         cfg_flags |= FIB_PATH_CFG_FLAG_ICMP_UNREACH;
1270     if (rpath->frp_flags & FIB_ROUTE_PATH_ICMP_PROHIBIT)
1271         cfg_flags |= FIB_PATH_CFG_FLAG_ICMP_PROHIBIT;
1272     if (rpath->frp_flags & FIB_ROUTE_PATH_GLEAN)
1273         cfg_flags |= FIB_PATH_CFG_FLAG_GLEAN;
1274
1275     return (cfg_flags);
1276 }
1277
1278 /*
1279  * fib_path_create
1280  *
1281  * Create and initialise a new path object.
1282  * return the index of the path.
1283  */
1284 fib_node_index_t
1285 fib_path_create (fib_node_index_t pl_index,
1286                  const fib_route_path_t *rpath)
1287 {
1288     fib_path_t *path;
1289
1290     pool_get(fib_path_pool, path);
1291     clib_memset(path, 0, sizeof(*path));
1292
1293     fib_node_init(&path->fp_node,
1294                   FIB_NODE_TYPE_PATH);
1295
1296     dpo_reset(&path->fp_dpo);
1297     path->fp_pl_index = pl_index;
1298     path->fp_nh_proto = rpath->frp_proto;
1299     path->fp_via_fib = FIB_NODE_INDEX_INVALID;
1300     path->fp_weight = rpath->frp_weight;
1301     if (0 == path->fp_weight)
1302     {
1303         /*
1304          * a weight of 0 is a meaningless value. We could either reject it, and thus force
1305          * clients to always use 1, or we can accept it and fixup approrpiately.
1306          */
1307         path->fp_weight = 1;
1308     }
1309     path->fp_preference = rpath->frp_preference;
1310     path->fp_cfg_flags = fib_path_route_flags_to_cfg_flags(rpath);
1311
1312     /*
1313      * deduce the path's tpye from the parementers and save what is needed.
1314      */
1315     if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_LOCAL)
1316     {
1317         path->fp_type = FIB_PATH_TYPE_RECEIVE;
1318         path->receive.fp_interface = rpath->frp_sw_if_index;
1319         path->receive.fp_addr = rpath->frp_addr;
1320     }
1321     else if (rpath->frp_flags & FIB_ROUTE_PATH_UDP_ENCAP)
1322     {
1323         path->fp_type = FIB_PATH_TYPE_UDP_ENCAP;
1324         path->udp_encap.fp_udp_encap_id = rpath->frp_udp_encap_id;
1325     }
1326     else if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_INTF_RX)
1327     {
1328         path->fp_type = FIB_PATH_TYPE_INTF_RX;
1329         path->intf_rx.fp_interface = rpath->frp_sw_if_index;
1330     }
1331     else if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_RPF_ID)
1332     {
1333         path->fp_type = FIB_PATH_TYPE_DEAG;
1334         path->deag.fp_tbl_id = rpath->frp_fib_index;
1335         path->deag.fp_rpf_id = rpath->frp_rpf_id;
1336     }
1337     else if (rpath->frp_flags & FIB_ROUTE_PATH_BIER_FMASK)
1338     {
1339         path->fp_type = FIB_PATH_TYPE_BIER_FMASK;
1340         path->bier_fmask.fp_bier_fmask = rpath->frp_bier_fmask;
1341     }
1342     else if (rpath->frp_flags & FIB_ROUTE_PATH_BIER_IMP)
1343     {
1344         path->fp_type = FIB_PATH_TYPE_BIER_IMP;
1345         path->bier_imp.fp_bier_imp = rpath->frp_bier_imp;
1346     }
1347     else if (rpath->frp_flags & FIB_ROUTE_PATH_BIER_TABLE)
1348     {
1349         path->fp_type = FIB_PATH_TYPE_BIER_TABLE;
1350         path->bier_table.fp_bier_tbl = rpath->frp_bier_tbl;
1351     }
1352     else if (rpath->frp_flags & FIB_ROUTE_PATH_DEAG)
1353     {
1354         path->fp_type = FIB_PATH_TYPE_DEAG;
1355         path->deag.fp_tbl_id = rpath->frp_fib_index;
1356     }
1357     else if (rpath->frp_flags & FIB_ROUTE_PATH_DVR)
1358     {
1359         path->fp_type = FIB_PATH_TYPE_DVR;
1360         path->dvr.fp_interface = rpath->frp_sw_if_index;
1361     }
1362     else if (rpath->frp_flags & FIB_ROUTE_PATH_EXCLUSIVE)
1363     {
1364         path->fp_type = FIB_PATH_TYPE_EXCLUSIVE;
1365         dpo_copy(&path->exclusive.fp_ex_dpo, &rpath->dpo);
1366     }
1367     else if ((path->fp_cfg_flags & FIB_PATH_CFG_FLAG_ICMP_PROHIBIT) ||
1368         (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_ICMP_UNREACH))
1369     {
1370         path->fp_type = FIB_PATH_TYPE_SPECIAL;
1371     }
1372     else if ((path->fp_cfg_flags & FIB_PATH_CFG_FLAG_CLASSIFY))
1373     {
1374         path->fp_type = FIB_PATH_TYPE_SPECIAL;
1375         path->classify.fp_classify_table_id = rpath->frp_classify_table_id;
1376     }
1377     else if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_GLEAN)
1378     {
1379         path->fp_type = FIB_PATH_TYPE_ATTACHED;
1380         path->attached.fp_interface = rpath->frp_sw_if_index;
1381         path->attached.fp_connected = rpath->frp_connected;
1382     }
1383     else if (~0 != rpath->frp_sw_if_index)
1384     {
1385         if (ip46_address_is_zero(&rpath->frp_addr))
1386         {
1387             path->fp_type = FIB_PATH_TYPE_ATTACHED;
1388             path->attached.fp_interface = rpath->frp_sw_if_index;
1389         }
1390         else
1391         {
1392             path->fp_type = FIB_PATH_TYPE_ATTACHED_NEXT_HOP;
1393             path->attached_next_hop.fp_interface = rpath->frp_sw_if_index;
1394             path->attached_next_hop.fp_nh = rpath->frp_addr;
1395         }
1396     }
1397     else
1398     {
1399         if (ip46_address_is_zero(&rpath->frp_addr))
1400         {
1401             if (~0 == rpath->frp_fib_index)
1402             {
1403                 path->fp_type = FIB_PATH_TYPE_SPECIAL;
1404             }
1405             else
1406             {
1407                 path->fp_type = FIB_PATH_TYPE_DEAG;
1408                 path->deag.fp_tbl_id = rpath->frp_fib_index;
1409                 path->deag.fp_rpf_id = ~0;
1410             }
1411         }
1412         else
1413         {
1414             path->fp_type = FIB_PATH_TYPE_RECURSIVE;
1415             if (DPO_PROTO_MPLS == path->fp_nh_proto)
1416             {
1417                 path->recursive.fp_nh.fp_local_label = rpath->frp_local_label;
1418                 path->recursive.fp_nh.fp_eos = rpath->frp_eos;
1419             }
1420             else
1421             {
1422                 path->recursive.fp_nh.fp_ip = rpath->frp_addr;
1423             }
1424             path->recursive.fp_tbl_id = rpath->frp_fib_index;
1425         }
1426     }
1427
1428     FIB_PATH_DBG(path, "create");
1429
1430     return (fib_path_get_index(path));
1431 }
1432
1433 /*
1434  * fib_path_create_special
1435  *
1436  * Create and initialise a new path object.
1437  * return the index of the path.
1438  */
1439 fib_node_index_t
1440 fib_path_create_special (fib_node_index_t pl_index,
1441                          dpo_proto_t nh_proto,
1442                          fib_path_cfg_flags_t flags,
1443                          const dpo_id_t *dpo)
1444 {
1445     fib_path_t *path;
1446
1447     pool_get(fib_path_pool, path);
1448     clib_memset(path, 0, sizeof(*path));
1449
1450     fib_node_init(&path->fp_node,
1451                   FIB_NODE_TYPE_PATH);
1452     dpo_reset(&path->fp_dpo);
1453
1454     path->fp_pl_index = pl_index;
1455     path->fp_weight = 1;
1456     path->fp_preference = 0;
1457     path->fp_nh_proto = nh_proto;
1458     path->fp_via_fib = FIB_NODE_INDEX_INVALID;
1459     path->fp_cfg_flags = flags;
1460
1461     if (FIB_PATH_CFG_FLAG_DROP & flags)
1462     {
1463         path->fp_type = FIB_PATH_TYPE_SPECIAL;
1464     }
1465     else if (FIB_PATH_CFG_FLAG_LOCAL & flags)
1466     {
1467         path->fp_type = FIB_PATH_TYPE_RECEIVE;
1468         path->attached.fp_interface = FIB_NODE_INDEX_INVALID;
1469     }
1470     else
1471     {
1472         path->fp_type = FIB_PATH_TYPE_EXCLUSIVE;
1473         ASSERT(NULL != dpo);
1474         dpo_copy(&path->exclusive.fp_ex_dpo, dpo);
1475     }
1476
1477     return (fib_path_get_index(path));
1478 }
1479
1480 /*
1481  * fib_path_copy
1482  *
1483  * Copy a path. return index of new path.
1484  */
1485 fib_node_index_t
1486 fib_path_copy (fib_node_index_t path_index,
1487                fib_node_index_t path_list_index)
1488 {
1489     fib_path_t *path, *orig_path;
1490
1491     pool_get(fib_path_pool, path);
1492
1493     orig_path = fib_path_get(path_index);
1494     ASSERT(NULL != orig_path);
1495
1496     clib_memcpy(path, orig_path, sizeof(*path));
1497
1498     FIB_PATH_DBG(path, "create-copy:%d", path_index);
1499
1500     /*
1501      * reset the dynamic section
1502      */
1503     fib_node_init(&path->fp_node, FIB_NODE_TYPE_PATH);
1504     path->fp_oper_flags     = FIB_PATH_OPER_FLAG_NONE;
1505     path->fp_pl_index  = path_list_index;
1506     path->fp_via_fib   = FIB_NODE_INDEX_INVALID;
1507     clib_memset(&path->fp_dpo, 0, sizeof(path->fp_dpo));
1508     dpo_reset(&path->fp_dpo);
1509
1510     if (path->fp_type == FIB_PATH_TYPE_EXCLUSIVE)
1511     {
1512         clib_memset(&path->exclusive.fp_ex_dpo, 0, sizeof(dpo_id_t));
1513         dpo_copy(&path->exclusive.fp_ex_dpo, &orig_path->exclusive.fp_ex_dpo);
1514     }
1515
1516     return (fib_path_get_index(path));
1517 }
1518
1519 /*
1520  * fib_path_destroy
1521  *
1522  * destroy a path that is no longer required
1523  */
1524 void
1525 fib_path_destroy (fib_node_index_t path_index)
1526 {
1527     fib_path_t *path;
1528
1529     path = fib_path_get(path_index);
1530
1531     ASSERT(NULL != path);
1532     FIB_PATH_DBG(path, "destroy");
1533
1534     fib_path_unresolve(path);
1535
1536     fib_node_deinit(&path->fp_node);
1537     pool_put(fib_path_pool, path);
1538 }
1539
1540 /*
1541  * fib_path_destroy
1542  *
1543  * destroy a path that is no longer required
1544  */
1545 uword
1546 fib_path_hash (fib_node_index_t path_index)
1547 {
1548     fib_path_t *path;
1549
1550     path = fib_path_get(path_index);
1551
1552     return (hash_memory(STRUCT_MARK_PTR(path, path_hash_start),
1553                         (STRUCT_OFFSET_OF(fib_path_t, path_hash_end) -
1554                          STRUCT_OFFSET_OF(fib_path_t, path_hash_start)),
1555                         0));
1556 }
1557
1558 /*
1559  * fib_path_cmp_i
1560  *
1561  * Compare two paths for equivalence.
1562  */
1563 static int
1564 fib_path_cmp_i (const fib_path_t *path1,
1565                 const fib_path_t *path2)
1566 {
1567     int res;
1568
1569     res = 1;
1570
1571     /*
1572      * paths of different types and protocol are not equal.
1573      * different weights and/or preference only are the same path.
1574      */
1575     if (path1->fp_type != path2->fp_type)
1576     {
1577         res = (path1->fp_type - path2->fp_type);
1578     }
1579     else if (path1->fp_nh_proto != path2->fp_nh_proto)
1580     {
1581         res = (path1->fp_nh_proto - path2->fp_nh_proto);
1582     }
1583     else
1584     {
1585         /*
1586          * both paths are of the same type.
1587          * consider each type and its attributes in turn.
1588          */
1589         switch (path1->fp_type)
1590         {
1591         case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
1592             res = ip46_address_cmp(&path1->attached_next_hop.fp_nh,
1593                                    &path2->attached_next_hop.fp_nh);
1594             if (0 == res) {
1595                 res = (path1->attached_next_hop.fp_interface -
1596                        path2->attached_next_hop.fp_interface);
1597             }
1598             break;
1599         case FIB_PATH_TYPE_ATTACHED:
1600             res = (path1->attached.fp_interface -
1601                    path2->attached.fp_interface);
1602             break;
1603         case FIB_PATH_TYPE_RECURSIVE:
1604             res = ip46_address_cmp(&path1->recursive.fp_nh.fp_ip,
1605                                    &path2->recursive.fp_nh.fp_ip);
1606
1607             if (0 == res)
1608             {
1609                 res = (path1->recursive.fp_tbl_id - path2->recursive.fp_tbl_id);
1610             }
1611             break;
1612         case FIB_PATH_TYPE_BIER_FMASK:
1613             res = (path1->bier_fmask.fp_bier_fmask -
1614                    path2->bier_fmask.fp_bier_fmask);
1615             break;
1616         case FIB_PATH_TYPE_BIER_IMP:
1617             res = (path1->bier_imp.fp_bier_imp -
1618                    path2->bier_imp.fp_bier_imp);
1619             break;
1620         case FIB_PATH_TYPE_BIER_TABLE:
1621             res = bier_table_id_cmp(&path1->bier_table.fp_bier_tbl,
1622                                     &path2->bier_table.fp_bier_tbl);
1623             break;
1624         case FIB_PATH_TYPE_DEAG:
1625             res = (path1->deag.fp_tbl_id - path2->deag.fp_tbl_id);
1626             if (0 == res)
1627             {
1628                 res = (path1->deag.fp_rpf_id - path2->deag.fp_rpf_id);
1629             }
1630             break;
1631         case FIB_PATH_TYPE_INTF_RX:
1632             res = (path1->intf_rx.fp_interface - path2->intf_rx.fp_interface);
1633             break;
1634         case FIB_PATH_TYPE_UDP_ENCAP:
1635             res = (path1->udp_encap.fp_udp_encap_id - path2->udp_encap.fp_udp_encap_id);
1636             break;
1637         case FIB_PATH_TYPE_DVR:
1638             res = (path1->dvr.fp_interface - path2->dvr.fp_interface);
1639             break;
1640         case FIB_PATH_TYPE_EXCLUSIVE:
1641             res = dpo_cmp(&path1->exclusive.fp_ex_dpo, &path2->exclusive.fp_ex_dpo);
1642             break;
1643         case FIB_PATH_TYPE_SPECIAL:
1644         case FIB_PATH_TYPE_RECEIVE:
1645             res = 0;
1646             break;
1647         }
1648     }
1649     return (res);
1650 }
1651
1652 /*
1653  * fib_path_cmp_for_sort
1654  *
1655  * Compare two paths for equivalence. Used during path sorting.
1656  * As usual 0 means equal.
1657  */
1658 int
1659 fib_path_cmp_for_sort (void * v1,
1660                        void * v2)
1661 {
1662     fib_node_index_t *pi1 = v1, *pi2 = v2;
1663     fib_path_t *path1, *path2;
1664
1665     path1 = fib_path_get(*pi1);
1666     path2 = fib_path_get(*pi2);
1667
1668     /*
1669      * when sorting paths we want the highest preference paths
1670      * first, so that the choices set built is in prefernce order
1671      */
1672     if (path1->fp_preference != path2->fp_preference)
1673     {
1674         return (path1->fp_preference - path2->fp_preference);
1675     }
1676
1677     return (fib_path_cmp_i(path1, path2));
1678 }
1679
1680 /*
1681  * fib_path_cmp
1682  *
1683  * Compare two paths for equivalence.
1684  */
1685 int
1686 fib_path_cmp (fib_node_index_t pi1,
1687               fib_node_index_t pi2)
1688 {
1689     fib_path_t *path1, *path2;
1690
1691     path1 = fib_path_get(pi1);
1692     path2 = fib_path_get(pi2);
1693
1694     return (fib_path_cmp_i(path1, path2));
1695 }
1696
1697 int
1698 fib_path_cmp_w_route_path (fib_node_index_t path_index,
1699                            const fib_route_path_t *rpath)
1700 {
1701     fib_path_t *path;
1702     int res;
1703
1704     path = fib_path_get(path_index);
1705
1706     res = 1;
1707
1708     if (path->fp_weight != rpath->frp_weight)
1709     {
1710         res = (path->fp_weight - rpath->frp_weight);
1711     }
1712     else
1713     {
1714         /*
1715          * both paths are of the same type.
1716          * consider each type and its attributes in turn.
1717          */
1718         switch (path->fp_type)
1719         {
1720         case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
1721             res = ip46_address_cmp(&path->attached_next_hop.fp_nh,
1722                                    &rpath->frp_addr);
1723             if (0 == res)
1724             {
1725                 res = (path->attached_next_hop.fp_interface -
1726                        rpath->frp_sw_if_index);
1727             }
1728             break;
1729         case FIB_PATH_TYPE_ATTACHED:
1730             res = (path->attached.fp_interface - rpath->frp_sw_if_index);
1731             break;
1732         case FIB_PATH_TYPE_RECURSIVE:
1733             if (DPO_PROTO_MPLS == path->fp_nh_proto)
1734             {
1735                 res = path->recursive.fp_nh.fp_local_label - rpath->frp_local_label;
1736
1737                 if (res == 0)
1738                 {
1739                     res = path->recursive.fp_nh.fp_eos - rpath->frp_eos;
1740                 }
1741             }
1742             else
1743             {
1744                 res = ip46_address_cmp(&path->recursive.fp_nh.fp_ip,
1745                                        &rpath->frp_addr);
1746             }
1747
1748             if (0 == res)
1749             {
1750                 res = (path->recursive.fp_tbl_id - rpath->frp_fib_index);
1751             }
1752             break;
1753         case FIB_PATH_TYPE_BIER_FMASK:
1754             res = (path->bier_fmask.fp_bier_fmask - rpath->frp_bier_fmask);
1755             break;
1756         case FIB_PATH_TYPE_BIER_IMP:
1757             res = (path->bier_imp.fp_bier_imp - rpath->frp_bier_imp);
1758             break;
1759         case FIB_PATH_TYPE_BIER_TABLE:
1760             res = bier_table_id_cmp(&path->bier_table.fp_bier_tbl,
1761                                     &rpath->frp_bier_tbl);
1762             break;
1763         case FIB_PATH_TYPE_INTF_RX:
1764             res = (path->intf_rx.fp_interface - rpath->frp_sw_if_index);
1765             break;
1766         case FIB_PATH_TYPE_UDP_ENCAP:
1767             res = (path->udp_encap.fp_udp_encap_id - rpath->frp_udp_encap_id);
1768             break;
1769         case FIB_PATH_TYPE_DEAG:
1770             res = (path->deag.fp_tbl_id - rpath->frp_fib_index);
1771             if (0 == res)
1772             {
1773                 res = (path->deag.fp_rpf_id - rpath->frp_rpf_id);
1774             }
1775             break;
1776         case FIB_PATH_TYPE_DVR:
1777             res = (path->dvr.fp_interface - rpath->frp_sw_if_index);
1778             break;
1779         case FIB_PATH_TYPE_EXCLUSIVE:
1780             res = dpo_cmp(&path->exclusive.fp_ex_dpo, &rpath->dpo);
1781             break;
1782         case FIB_PATH_TYPE_RECEIVE:
1783             if (rpath->frp_flags & FIB_ROUTE_PATH_LOCAL)
1784             {
1785                 res = 0;
1786             }
1787             else
1788             {
1789                 res = 1;
1790             }
1791             break;
1792         case FIB_PATH_TYPE_SPECIAL:
1793             res = 0;
1794             break;
1795         }
1796     }
1797     return (res);
1798 }
1799
1800 /*
1801  * fib_path_recursive_loop_detect
1802  *
1803  * A forward walk of the FIB object graph to detect for a cycle/loop. This
1804  * walk is initiated when an entry is linking to a new path list or from an old.
1805  * The entry vector passed contains all the FIB entrys that are children of this
1806  * path (it is all the entries encountered on the walk so far). If this vector
1807  * contains the entry this path resolve via, then a loop is about to form.
1808  * The loop must be allowed to form, since we need the dependencies in place
1809  * so that we can track when the loop breaks.
1810  * However, we MUST not produce a loop in the forwarding graph (else packets
1811  * would loop around the switch path until the loop breaks), so we mark recursive
1812  * paths as looped so that they do not contribute forwarding information.
1813  * By marking the path as looped, an etry such as;
1814  *    X/Y
1815  *     via a.a.a.a (looped)
1816  *     via b.b.b.b (not looped)
1817  * can still forward using the info provided by b.b.b.b only
1818  */
1819 int
1820 fib_path_recursive_loop_detect (fib_node_index_t path_index,
1821                                 fib_node_index_t **entry_indicies)
1822 {
1823     fib_path_t *path;
1824
1825     path = fib_path_get(path_index);
1826
1827     /*
1828      * the forced drop path is never looped, cos it is never resolved.
1829      */
1830     if (fib_path_is_permanent_drop(path))
1831     {
1832         return (0);
1833     }
1834
1835     switch (path->fp_type)
1836     {
1837     case FIB_PATH_TYPE_RECURSIVE:
1838     {
1839         fib_node_index_t *entry_index, *entries;
1840         int looped = 0;
1841         entries = *entry_indicies;
1842
1843         vec_foreach(entry_index, entries) {
1844             if (*entry_index == path->fp_via_fib)
1845             {
1846                 /*
1847                  * the entry that is about to link to this path-list (or
1848                  * one of this path-list's children) is the same entry that
1849                  * this recursive path resolves through. this is a cycle.
1850                  * abort the walk.
1851                  */
1852                 looped = 1;
1853                 break;
1854             }
1855         }
1856
1857         if (looped)
1858         {
1859             FIB_PATH_DBG(path, "recursive loop formed");
1860             path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RECURSIVE_LOOP;
1861
1862             dpo_copy(&path->fp_dpo, drop_dpo_get(path->fp_nh_proto));
1863         }
1864         else
1865         {
1866             /*
1867              * no loop here yet. keep forward walking the graph.
1868              */
1869             if (fib_entry_recursive_loop_detect(path->fp_via_fib, entry_indicies))
1870             {
1871                 FIB_PATH_DBG(path, "recursive loop formed");
1872                 path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RECURSIVE_LOOP;
1873             }
1874             else
1875             {
1876                 FIB_PATH_DBG(path, "recursive loop cleared");
1877                 path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RECURSIVE_LOOP;
1878             }
1879         }
1880         break;
1881     }
1882     case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
1883     case FIB_PATH_TYPE_ATTACHED:
1884         if (dpo_is_adj(&path->fp_dpo) &&
1885             adj_recursive_loop_detect(path->fp_dpo.dpoi_index,
1886                                       entry_indicies))
1887         {
1888             FIB_PATH_DBG(path, "recursive loop formed");
1889             path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RECURSIVE_LOOP;
1890         }
1891         else
1892         {
1893             FIB_PATH_DBG(path, "recursive loop cleared");
1894             path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RECURSIVE_LOOP;
1895         }
1896         break;
1897     case FIB_PATH_TYPE_SPECIAL:
1898     case FIB_PATH_TYPE_DEAG:
1899     case FIB_PATH_TYPE_DVR:
1900     case FIB_PATH_TYPE_RECEIVE:
1901     case FIB_PATH_TYPE_INTF_RX:
1902     case FIB_PATH_TYPE_UDP_ENCAP:
1903     case FIB_PATH_TYPE_EXCLUSIVE:
1904     case FIB_PATH_TYPE_BIER_FMASK:
1905     case FIB_PATH_TYPE_BIER_TABLE:
1906     case FIB_PATH_TYPE_BIER_IMP:
1907         /*
1908          * these path types cannot be part of a loop, since they are the leaves
1909          * of the graph.
1910          */
1911         break;
1912     }
1913
1914     return (fib_path_is_looped(path_index));
1915 }
1916
1917 int
1918 fib_path_resolve (fib_node_index_t path_index)
1919 {
1920     fib_path_t *path;
1921
1922     path = fib_path_get(path_index);
1923
1924     /*
1925      * hope for the best.
1926      */
1927     path->fp_oper_flags |= FIB_PATH_OPER_FLAG_RESOLVED;
1928
1929     /*
1930      * the forced drop path resolves via the drop adj
1931      */
1932     if (fib_path_is_permanent_drop(path))
1933     {
1934         dpo_copy(&path->fp_dpo, drop_dpo_get(path->fp_nh_proto));
1935         path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
1936         return (fib_path_is_resolved(path_index));
1937     }
1938
1939     switch (path->fp_type)
1940     {
1941     case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
1942         fib_path_attached_next_hop_set(path);
1943         break;
1944     case FIB_PATH_TYPE_ATTACHED:
1945     {
1946         dpo_id_t tmp = DPO_INVALID;
1947
1948         /*
1949          * path->attached.fp_interface
1950          */
1951         if (!vnet_sw_interface_is_up(vnet_get_main(),
1952                                      path->attached.fp_interface))
1953         {
1954             path->fp_oper_flags &= ~FIB_PATH_OPER_FLAG_RESOLVED;
1955         }
1956         fib_path_attached_get_adj(path,
1957                                   dpo_proto_to_link(path->fp_nh_proto),
1958                                   &tmp);
1959
1960         /*
1961          * re-fetch after possible mem realloc
1962          */
1963         path = fib_path_get(path_index);
1964         dpo_copy(&path->fp_dpo, &tmp);
1965
1966         /*
1967          * become a child of the adjacency so we receive updates
1968          * when the interface state changes
1969          */
1970         if (dpo_is_adj(&path->fp_dpo))
1971         {
1972             path->fp_sibling = adj_child_add(path->fp_dpo.dpoi_index,
1973                                              FIB_NODE_TYPE_PATH,
1974                                              fib_path_get_index(path));
1975         }
1976         dpo_reset(&tmp);
1977         break;
1978     }
1979     case FIB_PATH_TYPE_RECURSIVE:
1980     {
1981         /*
1982          * Create a RR source entry in the table for the address
1983          * that this path recurses through.
1984          * This resolve action is recursive, hence we may create
1985          * more paths in the process. more creates mean maybe realloc
1986          * of this path.
1987          */
1988         fib_node_index_t fei;
1989         fib_prefix_t pfx;
1990
1991         ASSERT(FIB_NODE_INDEX_INVALID == path->fp_via_fib);
1992
1993         if (DPO_PROTO_MPLS == path->fp_nh_proto)
1994         {
1995             fib_prefix_from_mpls_label(path->recursive.fp_nh.fp_local_label,
1996                                        path->recursive.fp_nh.fp_eos,
1997                                        &pfx);
1998         }
1999         else
2000         {
2001             ASSERT(!ip46_address_is_zero(&path->recursive.fp_nh.fp_ip));
2002
2003             fib_protocol_t fp = (ip46_address_is_ip4(&path->recursive.fp_nh.fp_ip) ?
2004                                         FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6);
2005             fib_prefix_from_ip46_addr(fp, &path->recursive.fp_nh.fp_ip, &pfx);
2006         }
2007
2008         fib_table_lock(path->recursive.fp_tbl_id,
2009                        dpo_proto_to_fib(path->fp_nh_proto),
2010                        FIB_SOURCE_RR);
2011         fei = fib_table_entry_special_add(path->recursive.fp_tbl_id,
2012                                           &pfx,
2013                                           FIB_SOURCE_RR,
2014                                           FIB_ENTRY_FLAG_NONE);
2015
2016         path = fib_path_get(path_index);
2017         path->fp_via_fib = fei;
2018
2019         /*
2020          * become a dependent child of the entry so the path is
2021          * informed when the forwarding for the entry changes.
2022          */
2023         path->fp_sibling = fib_entry_child_add(path->fp_via_fib,
2024                                                FIB_NODE_TYPE_PATH,
2025                                                fib_path_get_index(path));
2026
2027         /*
2028          * create and configure the IP DPO
2029          */
2030         fib_path_recursive_adj_update(
2031             path,
2032             fib_path_to_chain_type(path),
2033             &path->fp_dpo);
2034
2035         break;
2036     }
2037     case FIB_PATH_TYPE_BIER_FMASK:
2038     {
2039         /*
2040          * become a dependent child of the entry so the path is
2041          * informed when the forwarding for the entry changes.
2042          */
2043         path->fp_sibling = bier_fmask_child_add(path->bier_fmask.fp_bier_fmask,
2044                                                 FIB_NODE_TYPE_PATH,
2045                                                 fib_path_get_index(path));
2046
2047         path->fp_via_bier_fmask = path->bier_fmask.fp_bier_fmask;
2048         fib_path_bier_fmask_update(path, &path->fp_dpo);
2049
2050         break;
2051     }
2052     case FIB_PATH_TYPE_BIER_IMP:
2053         bier_imp_lock(path->bier_imp.fp_bier_imp);
2054         bier_imp_contribute_forwarding(path->bier_imp.fp_bier_imp,
2055                                        DPO_PROTO_IP4,
2056                                        &path->fp_dpo);
2057         break;
2058     case FIB_PATH_TYPE_BIER_TABLE:
2059     {
2060         /*
2061          * Find/create the BIER table to link to
2062          */
2063         ASSERT(FIB_NODE_INDEX_INVALID == path->fp_via_bier_tbl);
2064
2065         path->fp_via_bier_tbl =
2066             bier_table_ecmp_create_and_lock(&path->bier_table.fp_bier_tbl);
2067
2068         bier_table_contribute_forwarding(path->fp_via_bier_tbl,
2069                                          &path->fp_dpo);
2070         break;
2071     }
2072     case FIB_PATH_TYPE_SPECIAL:
2073         if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_ICMP_PROHIBIT)
2074         {
2075             ip_null_dpo_add_and_lock (path->fp_nh_proto,
2076                                       IP_NULL_ACTION_SEND_ICMP_PROHIBIT,
2077                                       &path->fp_dpo);
2078         }
2079         else if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_ICMP_UNREACH)
2080         {
2081             ip_null_dpo_add_and_lock (path->fp_nh_proto,
2082                                       IP_NULL_ACTION_SEND_ICMP_UNREACH,
2083                                       &path->fp_dpo);
2084         }
2085         else if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_CLASSIFY)
2086         {
2087             dpo_set (&path->fp_dpo, DPO_CLASSIFY,
2088                      path->fp_nh_proto,
2089                      classify_dpo_create (path->fp_nh_proto,
2090                                           path->classify.fp_classify_table_id));
2091         }
2092         else
2093         {
2094             /*
2095              * Resolve via the drop
2096              */
2097             dpo_copy(&path->fp_dpo, drop_dpo_get(path->fp_nh_proto));
2098         }
2099         break;
2100     case FIB_PATH_TYPE_DEAG:
2101     {
2102         if (DPO_PROTO_BIER == path->fp_nh_proto)
2103         {
2104             bier_disp_table_contribute_forwarding(path->deag.fp_tbl_id,
2105                                                   &path->fp_dpo);
2106         }
2107         else
2108         {
2109             /*
2110              * Resolve via a lookup DPO.
2111              * FIXME. control plane should add routes with a table ID
2112              */
2113             lookup_input_t input;
2114             lookup_cast_t cast;
2115
2116             cast = (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_RPF_ID ?
2117                     LOOKUP_MULTICAST :
2118                     LOOKUP_UNICAST);
2119             input = (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_DEAG_SRC ?
2120                      LOOKUP_INPUT_SRC_ADDR :
2121                      LOOKUP_INPUT_DST_ADDR);
2122
2123             lookup_dpo_add_or_lock_w_fib_index(path->deag.fp_tbl_id,
2124                                                path->fp_nh_proto,
2125                                                cast,
2126                                                input,
2127                                                LOOKUP_TABLE_FROM_CONFIG,
2128                                                &path->fp_dpo);
2129         }
2130         break;
2131     }
2132     case FIB_PATH_TYPE_DVR:
2133         dvr_dpo_add_or_lock(path->dvr.fp_interface,
2134                             path->fp_nh_proto,
2135                             &path->fp_dpo);
2136         break;
2137     case FIB_PATH_TYPE_RECEIVE:
2138         /*
2139          * Resolve via a receive DPO.
2140          */
2141         receive_dpo_add_or_lock(path->fp_nh_proto,
2142                                 path->receive.fp_interface,
2143                                 &path->receive.fp_addr,
2144                                 &path->fp_dpo);
2145         break;
2146     case FIB_PATH_TYPE_UDP_ENCAP:
2147         udp_encap_lock(path->udp_encap.fp_udp_encap_id);
2148         udp_encap_contribute_forwarding(path->udp_encap.fp_udp_encap_id,
2149                                         path->fp_nh_proto,
2150                                         &path->fp_dpo);
2151         break;
2152     case FIB_PATH_TYPE_INTF_RX: {
2153         /*
2154          * Resolve via a receive DPO.
2155          */
2156         interface_rx_dpo_add_or_lock(path->fp_nh_proto,
2157                                      path->intf_rx.fp_interface,
2158                                      &path->fp_dpo);
2159         break;
2160     }
2161     case FIB_PATH_TYPE_EXCLUSIVE:
2162         /*
2163          * Resolve via the user provided DPO
2164          */
2165         dpo_copy(&path->fp_dpo, &path->exclusive.fp_ex_dpo);
2166         break;
2167     }
2168
2169     return (fib_path_is_resolved(path_index));
2170 }
2171
2172 u32
2173 fib_path_get_resolving_interface (fib_node_index_t path_index)
2174 {
2175     fib_path_t *path;
2176
2177     path = fib_path_get(path_index);
2178
2179     switch (path->fp_type)
2180     {
2181     case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
2182         return (path->attached_next_hop.fp_interface);
2183     case FIB_PATH_TYPE_ATTACHED:
2184         return (path->attached.fp_interface);
2185     case FIB_PATH_TYPE_RECEIVE:
2186         return (path->receive.fp_interface);
2187     case FIB_PATH_TYPE_RECURSIVE:
2188         if (fib_path_is_resolved(path_index))
2189         {
2190             return (fib_entry_get_resolving_interface(path->fp_via_fib));
2191         }
2192         break;
2193     case FIB_PATH_TYPE_DVR:
2194         return (path->dvr.fp_interface);
2195     case FIB_PATH_TYPE_INTF_RX:
2196     case FIB_PATH_TYPE_UDP_ENCAP:
2197     case FIB_PATH_TYPE_SPECIAL:
2198     case FIB_PATH_TYPE_DEAG:
2199     case FIB_PATH_TYPE_EXCLUSIVE:
2200     case FIB_PATH_TYPE_BIER_FMASK:
2201     case FIB_PATH_TYPE_BIER_TABLE:
2202     case FIB_PATH_TYPE_BIER_IMP:
2203         break;
2204     }
2205     return (dpo_get_urpf(&path->fp_dpo));
2206 }
2207
2208 index_t
2209 fib_path_get_resolving_index (fib_node_index_t path_index)
2210 {
2211     fib_path_t *path;
2212
2213     path = fib_path_get(path_index);
2214
2215     switch (path->fp_type)
2216     {
2217     case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
2218     case FIB_PATH_TYPE_ATTACHED:
2219     case FIB_PATH_TYPE_RECEIVE:
2220     case FIB_PATH_TYPE_INTF_RX:
2221     case FIB_PATH_TYPE_SPECIAL:
2222     case FIB_PATH_TYPE_DEAG:
2223     case FIB_PATH_TYPE_DVR:
2224     case FIB_PATH_TYPE_EXCLUSIVE:
2225         break;
2226     case FIB_PATH_TYPE_UDP_ENCAP:
2227         return (path->udp_encap.fp_udp_encap_id);
2228     case FIB_PATH_TYPE_RECURSIVE:
2229         return (path->fp_via_fib);
2230     case FIB_PATH_TYPE_BIER_FMASK:
2231         return (path->bier_fmask.fp_bier_fmask);
2232    case FIB_PATH_TYPE_BIER_TABLE:
2233        return (path->fp_via_bier_tbl);
2234    case FIB_PATH_TYPE_BIER_IMP:
2235        return (path->bier_imp.fp_bier_imp);
2236     }
2237     return (~0);
2238 }
2239
2240 adj_index_t
2241 fib_path_get_adj (fib_node_index_t path_index)
2242 {
2243     fib_path_t *path;
2244
2245     path = fib_path_get(path_index);
2246
2247     if (dpo_is_adj(&path->fp_dpo))
2248     {
2249         return (path->fp_dpo.dpoi_index);
2250     }
2251     return (ADJ_INDEX_INVALID);
2252 }
2253
2254 u16
2255 fib_path_get_weight (fib_node_index_t path_index)
2256 {
2257     fib_path_t *path;
2258
2259     path = fib_path_get(path_index);
2260
2261     ASSERT(path);
2262
2263     return (path->fp_weight);
2264 }
2265
2266 u16
2267 fib_path_get_preference (fib_node_index_t path_index)
2268 {
2269     fib_path_t *path;
2270
2271     path = fib_path_get(path_index);
2272
2273     ASSERT(path);
2274
2275     return (path->fp_preference);
2276 }
2277
2278 u32
2279 fib_path_get_rpf_id (fib_node_index_t path_index)
2280 {
2281     fib_path_t *path;
2282
2283     path = fib_path_get(path_index);
2284
2285     ASSERT(path);
2286
2287     if (FIB_PATH_CFG_FLAG_RPF_ID & path->fp_cfg_flags)
2288     {
2289         return (path->deag.fp_rpf_id);
2290     }
2291
2292     return (~0);
2293 }
2294
2295 /**
2296  * @brief Contribute the path's adjacency to the list passed.
2297  * By calling this function over all paths, recursively, a child
2298  * can construct its full set of forwarding adjacencies, and hence its
2299  * uRPF list.
2300  */
2301 void
2302 fib_path_contribute_urpf (fib_node_index_t path_index,
2303                           index_t urpf)
2304 {
2305     fib_path_t *path;
2306
2307     path = fib_path_get(path_index);
2308
2309     /*
2310      * resolved and unresolved paths contribute to the RPF list.
2311      */
2312     switch (path->fp_type)
2313     {
2314     case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
2315         fib_urpf_list_append(urpf, path->attached_next_hop.fp_interface);
2316         break;
2317
2318     case FIB_PATH_TYPE_ATTACHED:
2319         fib_urpf_list_append(urpf, path->attached.fp_interface);
2320         break;
2321
2322     case FIB_PATH_TYPE_RECURSIVE:
2323         if (FIB_NODE_INDEX_INVALID != path->fp_via_fib &&
2324             !fib_path_is_looped(path_index))
2325         {
2326             /*
2327              * there's unresolved due to constraints, and there's unresolved
2328              * due to ain't got no via. can't do nowt w'out via.
2329              */
2330             fib_entry_contribute_urpf(path->fp_via_fib, urpf);
2331         }
2332         break;
2333
2334     case FIB_PATH_TYPE_EXCLUSIVE:
2335     case FIB_PATH_TYPE_SPECIAL:
2336     {
2337         /*
2338          * these path types may link to an adj, if that's what
2339          * the clinet gave
2340          */
2341         u32 rpf_sw_if_index;
2342
2343         rpf_sw_if_index = dpo_get_urpf(&path->fp_dpo);
2344
2345         if (~0 != rpf_sw_if_index)
2346         {
2347             fib_urpf_list_append(urpf, rpf_sw_if_index);
2348         }
2349         break;
2350     }
2351     case FIB_PATH_TYPE_DVR:
2352         fib_urpf_list_append(urpf, path->dvr.fp_interface);
2353         break;
2354     case FIB_PATH_TYPE_UDP_ENCAP:
2355         fib_urpf_list_append(urpf, path->udp_encap.fp_udp_encap_id);
2356         break;
2357     case FIB_PATH_TYPE_DEAG:
2358     case FIB_PATH_TYPE_RECEIVE:
2359     case FIB_PATH_TYPE_INTF_RX:
2360     case FIB_PATH_TYPE_BIER_FMASK:
2361     case FIB_PATH_TYPE_BIER_TABLE:
2362     case FIB_PATH_TYPE_BIER_IMP:
2363         /*
2364          * these path types don't link to an adj
2365          */
2366         break;
2367     }
2368 }
2369
2370 void
2371 fib_path_stack_mpls_disp (fib_node_index_t path_index,
2372                           dpo_proto_t payload_proto,
2373                           fib_mpls_lsp_mode_t mode,
2374                           dpo_id_t *dpo)
2375 {
2376     fib_path_t *path;
2377
2378     path = fib_path_get(path_index);
2379
2380     ASSERT(path);
2381
2382     switch (path->fp_type)
2383     {
2384     case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
2385     {
2386         dpo_id_t tmp = DPO_INVALID;
2387
2388         dpo_copy(&tmp, dpo);
2389
2390         mpls_disp_dpo_create(payload_proto, ~0, mode, &tmp, dpo);
2391         dpo_reset(&tmp);
2392         break;
2393     }
2394     case FIB_PATH_TYPE_DEAG:
2395     {
2396         dpo_id_t tmp = DPO_INVALID;
2397
2398         dpo_copy(&tmp, dpo);
2399
2400         mpls_disp_dpo_create(payload_proto,
2401                              path->deag.fp_rpf_id,
2402                              mode, &tmp, dpo);
2403         dpo_reset(&tmp);
2404         break;
2405     }
2406     case FIB_PATH_TYPE_RECEIVE:
2407     case FIB_PATH_TYPE_ATTACHED:
2408     case FIB_PATH_TYPE_RECURSIVE:
2409     case FIB_PATH_TYPE_INTF_RX:
2410     case FIB_PATH_TYPE_UDP_ENCAP:
2411     case FIB_PATH_TYPE_EXCLUSIVE:
2412     case FIB_PATH_TYPE_SPECIAL:
2413     case FIB_PATH_TYPE_BIER_FMASK:
2414     case FIB_PATH_TYPE_BIER_TABLE:
2415     case FIB_PATH_TYPE_BIER_IMP:
2416     case FIB_PATH_TYPE_DVR:
2417         break;
2418     }
2419
2420     if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_POP_PW_CW)
2421     {
2422         dpo_id_t tmp = DPO_INVALID;
2423
2424         dpo_copy(&tmp, dpo);
2425
2426         pw_cw_dpo_create(&tmp, dpo);
2427         dpo_reset(&tmp);
2428     }
2429 }
2430
2431 void
2432 fib_path_contribute_forwarding (fib_node_index_t path_index,
2433                                 fib_forward_chain_type_t fct,
2434                                 dpo_proto_t payload_proto,
2435                                 dpo_id_t *dpo)
2436 {
2437     fib_path_t *path;
2438
2439     path = fib_path_get(path_index);
2440
2441     ASSERT(path);
2442
2443     /*
2444      * The DPO stored in the path was created when the path was resolved.
2445      * This then represents the path's 'native' protocol; IP.
2446      * For all others will need to go find something else.
2447      */
2448     if (fib_path_to_chain_type(path) == fct)
2449     {
2450         dpo_copy(dpo, &path->fp_dpo);
2451     }
2452     else
2453     {
2454         switch (path->fp_type)
2455         {
2456         case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
2457             switch (fct)
2458             {
2459             case FIB_FORW_CHAIN_TYPE_MPLS_EOS: {
2460                     dpo_id_t tmp = DPO_INVALID;
2461                     dpo_copy (&tmp, dpo);
2462                     path = fib_path_attached_next_hop_get_adj(
2463                            path,
2464                            dpo_proto_to_link(payload_proto),
2465                            &tmp);
2466                     dpo_copy (dpo, &tmp);
2467                     dpo_reset(&tmp);
2468                     break;
2469             }
2470             case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
2471             case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
2472             case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
2473             case FIB_FORW_CHAIN_TYPE_ETHERNET:
2474             case FIB_FORW_CHAIN_TYPE_NSH:
2475             case FIB_FORW_CHAIN_TYPE_MCAST_IP4:
2476             case FIB_FORW_CHAIN_TYPE_MCAST_IP6:
2477                 {
2478                     dpo_id_t tmp = DPO_INVALID;
2479                     dpo_copy (&tmp, dpo);
2480                     path = fib_path_attached_next_hop_get_adj(
2481                            path,
2482                            fib_forw_chain_type_to_link_type(fct),
2483                            &tmp);
2484                     dpo_copy (dpo, &tmp);
2485                     dpo_reset(&tmp);
2486                     break;
2487                 }
2488             case FIB_FORW_CHAIN_TYPE_BIER:
2489                 break;
2490             }
2491             break;
2492         case FIB_PATH_TYPE_RECURSIVE:
2493             switch (fct)
2494             {
2495             case FIB_FORW_CHAIN_TYPE_MPLS_EOS:
2496             case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
2497             case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
2498             case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
2499             case FIB_FORW_CHAIN_TYPE_MCAST_IP4:
2500             case FIB_FORW_CHAIN_TYPE_MCAST_IP6:
2501             case FIB_FORW_CHAIN_TYPE_BIER:
2502                 fib_path_recursive_adj_update(path, fct, dpo);
2503                 break;
2504             case FIB_FORW_CHAIN_TYPE_ETHERNET:
2505             case FIB_FORW_CHAIN_TYPE_NSH:
2506                 ASSERT(0);
2507                 break;
2508             }
2509             break;
2510         case FIB_PATH_TYPE_BIER_TABLE:
2511             switch (fct)
2512             {
2513             case FIB_FORW_CHAIN_TYPE_BIER:
2514                 bier_table_contribute_forwarding(path->fp_via_bier_tbl, dpo);
2515                 break;
2516             case FIB_FORW_CHAIN_TYPE_MPLS_EOS:
2517             case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
2518             case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
2519             case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
2520             case FIB_FORW_CHAIN_TYPE_MCAST_IP4:
2521             case FIB_FORW_CHAIN_TYPE_MCAST_IP6:
2522             case FIB_FORW_CHAIN_TYPE_ETHERNET:
2523             case FIB_FORW_CHAIN_TYPE_NSH:
2524                 ASSERT(0);
2525                 break;
2526             }
2527             break;
2528         case FIB_PATH_TYPE_BIER_FMASK:
2529             switch (fct)
2530             {
2531             case FIB_FORW_CHAIN_TYPE_BIER:
2532                 fib_path_bier_fmask_update(path, dpo);
2533                 break;
2534             case FIB_FORW_CHAIN_TYPE_MPLS_EOS:
2535             case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
2536             case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
2537             case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
2538             case FIB_FORW_CHAIN_TYPE_MCAST_IP4:
2539             case FIB_FORW_CHAIN_TYPE_MCAST_IP6:
2540             case FIB_FORW_CHAIN_TYPE_ETHERNET:
2541             case FIB_FORW_CHAIN_TYPE_NSH:
2542                 ASSERT(0);
2543                 break;
2544             }
2545             break;
2546         case FIB_PATH_TYPE_BIER_IMP:
2547             bier_imp_contribute_forwarding(path->bier_imp.fp_bier_imp,
2548                                            fib_forw_chain_type_to_dpo_proto(fct),
2549                                            dpo);
2550             break;
2551         case FIB_PATH_TYPE_DEAG:
2552             switch (fct)
2553             {
2554             case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
2555                 lookup_dpo_add_or_lock_w_table_id(MPLS_FIB_DEFAULT_TABLE_ID,
2556                                                   DPO_PROTO_MPLS,
2557                                                   LOOKUP_UNICAST,
2558                                                   LOOKUP_INPUT_DST_ADDR,
2559                                                   LOOKUP_TABLE_FROM_CONFIG,
2560                                                   dpo);
2561                 break;
2562             case FIB_FORW_CHAIN_TYPE_MPLS_EOS:
2563             case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
2564             case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
2565             case FIB_FORW_CHAIN_TYPE_MCAST_IP4:
2566             case FIB_FORW_CHAIN_TYPE_MCAST_IP6:
2567                 dpo_copy(dpo, &path->fp_dpo);
2568                 break;
2569             case FIB_FORW_CHAIN_TYPE_BIER:
2570                 break;
2571             case FIB_FORW_CHAIN_TYPE_ETHERNET:
2572             case FIB_FORW_CHAIN_TYPE_NSH:
2573                 ASSERT(0);
2574                 break;
2575             }
2576             break;
2577         case FIB_PATH_TYPE_EXCLUSIVE:
2578             dpo_copy(dpo, &path->exclusive.fp_ex_dpo);
2579             break;
2580         case FIB_PATH_TYPE_ATTACHED:
2581             switch (fct)
2582             {
2583             case FIB_FORW_CHAIN_TYPE_MPLS_EOS:
2584                 /*
2585                  * End of stack traffic via an attacehd path (a glean)
2586                  * must forace an IP lookup so that the IP packet can
2587                  * match against any installed adj-fibs
2588                  */
2589                 lookup_dpo_add_or_lock_w_fib_index(
2590                     fib_table_get_index_for_sw_if_index(
2591                         dpo_proto_to_fib(payload_proto),
2592                         path->attached.fp_interface),
2593                     payload_proto,
2594                     LOOKUP_UNICAST,
2595                     LOOKUP_INPUT_DST_ADDR,
2596                     LOOKUP_TABLE_FROM_CONFIG,
2597                     dpo);
2598                 break;
2599             case FIB_FORW_CHAIN_TYPE_MPLS_NON_EOS:
2600             case FIB_FORW_CHAIN_TYPE_UNICAST_IP4:
2601             case FIB_FORW_CHAIN_TYPE_UNICAST_IP6:
2602             case FIB_FORW_CHAIN_TYPE_ETHERNET:
2603             case FIB_FORW_CHAIN_TYPE_NSH:
2604             case FIB_FORW_CHAIN_TYPE_BIER:
2605                 fib_path_attached_get_adj(path,
2606                                           fib_forw_chain_type_to_link_type(fct),
2607                                           dpo);
2608                 break;
2609             case FIB_FORW_CHAIN_TYPE_MCAST_IP4:
2610             case FIB_FORW_CHAIN_TYPE_MCAST_IP6:
2611                 {
2612                     adj_index_t ai;
2613
2614                     /*
2615                      * Create the adj needed for sending IP multicast traffic
2616                      */
2617                     if (vnet_sw_interface_is_p2p(vnet_get_main(),
2618                                                  path->attached.fp_interface))
2619                     {
2620                         /*
2621                          * point-2-point interfaces do not require a glean, since
2622                          * there is nothing to ARP. Install a rewrite/nbr adj instead
2623                          */
2624                         ai = adj_nbr_add_or_lock(dpo_proto_to_fib(path->fp_nh_proto),
2625                                                  fib_forw_chain_type_to_link_type(fct),
2626                                                  &zero_addr,
2627                                                  path->attached.fp_interface);
2628                     }
2629                     else
2630                     {
2631                         ai = adj_mcast_add_or_lock(dpo_proto_to_fib(path->fp_nh_proto),
2632                                                    fib_forw_chain_type_to_link_type(fct),
2633                                                    path->attached.fp_interface);
2634                     }
2635                     dpo_set(dpo, DPO_ADJACENCY,
2636                             fib_forw_chain_type_to_dpo_proto(fct),
2637                             ai);
2638                     adj_unlock(ai);
2639                 }
2640                 break;
2641             }
2642             break;
2643         case FIB_PATH_TYPE_INTF_RX:
2644             /*
2645              * Create the adj needed for sending IP multicast traffic
2646              */
2647             interface_rx_dpo_add_or_lock(payload_proto,
2648                                          path->intf_rx.fp_interface,
2649                                          dpo);
2650             break;
2651         case FIB_PATH_TYPE_UDP_ENCAP:
2652             udp_encap_contribute_forwarding(path->udp_encap.fp_udp_encap_id,
2653                                             path->fp_nh_proto,
2654                                             dpo);
2655             break;
2656         case FIB_PATH_TYPE_RECEIVE:
2657         case FIB_PATH_TYPE_SPECIAL:
2658         case FIB_PATH_TYPE_DVR:
2659             dpo_copy(dpo, &path->fp_dpo);
2660             break;
2661         }
2662     }
2663 }
2664
2665 load_balance_path_t *
2666 fib_path_append_nh_for_multipath_hash (fib_node_index_t path_index,
2667                                        fib_forward_chain_type_t fct,
2668                                        dpo_proto_t payload_proto,
2669                                        load_balance_path_t *hash_key)
2670 {
2671     load_balance_path_t *mnh;
2672     fib_path_t *path;
2673
2674     path = fib_path_get(path_index);
2675
2676     ASSERT(path);
2677
2678     vec_add2(hash_key, mnh, 1);
2679
2680     mnh->path_weight = path->fp_weight;
2681     mnh->path_index = path_index;
2682
2683     if (fib_path_is_resolved(path_index))
2684     {
2685         fib_path_contribute_forwarding(path_index, fct, payload_proto, &mnh->path_dpo);
2686     }
2687     else
2688     {
2689         dpo_copy(&mnh->path_dpo,
2690                  drop_dpo_get(fib_forw_chain_type_to_dpo_proto(fct)));
2691     }
2692     return (hash_key);
2693 }
2694
2695 int
2696 fib_path_is_recursive_constrained (fib_node_index_t path_index)
2697 {
2698     fib_path_t *path;
2699
2700     path = fib_path_get(path_index);
2701
2702     return ((FIB_PATH_TYPE_RECURSIVE == path->fp_type) &&
2703             ((path->fp_cfg_flags & FIB_PATH_CFG_FLAG_RESOLVE_ATTACHED) ||
2704              (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_RESOLVE_HOST)));
2705 }
2706
2707 int
2708 fib_path_is_exclusive (fib_node_index_t path_index)
2709 {
2710     fib_path_t *path;
2711
2712     path = fib_path_get(path_index);
2713
2714     return (FIB_PATH_TYPE_EXCLUSIVE == path->fp_type);
2715 }
2716
2717 int
2718 fib_path_is_deag (fib_node_index_t path_index)
2719 {
2720     fib_path_t *path;
2721
2722     path = fib_path_get(path_index);
2723
2724     return (FIB_PATH_TYPE_DEAG == path->fp_type);
2725 }
2726
2727 int
2728 fib_path_is_resolved (fib_node_index_t path_index)
2729 {
2730     fib_path_t *path;
2731
2732     path = fib_path_get(path_index);
2733
2734     return (dpo_id_is_valid(&path->fp_dpo) &&
2735             (path->fp_oper_flags & FIB_PATH_OPER_FLAG_RESOLVED) &&
2736             !fib_path_is_looped(path_index) &&
2737             !fib_path_is_permanent_drop(path));
2738 }
2739
2740 int
2741 fib_path_is_looped (fib_node_index_t path_index)
2742 {
2743     fib_path_t *path;
2744
2745     path = fib_path_get(path_index);
2746
2747     return (path->fp_oper_flags & FIB_PATH_OPER_FLAG_RECURSIVE_LOOP);
2748 }
2749
2750 fib_path_list_walk_rc_t
2751 fib_path_encode (fib_node_index_t path_list_index,
2752                  fib_node_index_t path_index,
2753                  const fib_path_ext_t *path_ext,
2754                  void *args)
2755 {
2756     fib_path_encode_ctx_t *ctx = args;
2757     fib_route_path_t *rpath;
2758     fib_path_t *path;
2759
2760     path = fib_path_get(path_index);
2761     if (!path)
2762       return (FIB_PATH_LIST_WALK_CONTINUE);
2763
2764     vec_add2(ctx->rpaths, rpath, 1);
2765     rpath->frp_weight = path->fp_weight;
2766     rpath->frp_preference = path->fp_preference;
2767     rpath->frp_proto = path->fp_nh_proto;
2768     rpath->frp_sw_if_index = ~0;
2769     rpath->frp_fib_index = 0;
2770
2771     switch (path->fp_type)
2772     {
2773       case FIB_PATH_TYPE_RECEIVE:
2774         rpath->frp_addr = path->receive.fp_addr;
2775         rpath->frp_sw_if_index = path->receive.fp_interface;
2776         rpath->frp_flags |= FIB_ROUTE_PATH_LOCAL;
2777         break;
2778       case FIB_PATH_TYPE_ATTACHED:
2779         rpath->frp_sw_if_index = path->attached.fp_interface;
2780         break;
2781       case FIB_PATH_TYPE_ATTACHED_NEXT_HOP:
2782         rpath->frp_sw_if_index = path->attached_next_hop.fp_interface;
2783         rpath->frp_addr = path->attached_next_hop.fp_nh;
2784         break;
2785       case FIB_PATH_TYPE_BIER_FMASK:
2786         rpath->frp_bier_fmask = path->bier_fmask.fp_bier_fmask;
2787         break;
2788       case FIB_PATH_TYPE_SPECIAL:
2789         break;
2790       case FIB_PATH_TYPE_DEAG:
2791         rpath->frp_fib_index = path->deag.fp_tbl_id;
2792         if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_RPF_ID)
2793         {
2794             rpath->frp_flags |= FIB_ROUTE_PATH_RPF_ID;
2795         }
2796         break;
2797       case FIB_PATH_TYPE_RECURSIVE:
2798         rpath->frp_addr = path->recursive.fp_nh.fp_ip;
2799         rpath->frp_fib_index = path->recursive.fp_tbl_id;
2800         break;
2801       case FIB_PATH_TYPE_DVR:
2802           rpath->frp_sw_if_index = path->dvr.fp_interface;
2803           rpath->frp_flags |= FIB_ROUTE_PATH_DVR;
2804           break;
2805       case FIB_PATH_TYPE_UDP_ENCAP:
2806           rpath->frp_udp_encap_id = path->udp_encap.fp_udp_encap_id;
2807           rpath->frp_flags |= FIB_ROUTE_PATH_UDP_ENCAP;
2808           break;
2809       case FIB_PATH_TYPE_INTF_RX:
2810           rpath->frp_sw_if_index = path->receive.fp_interface;
2811           rpath->frp_flags |= FIB_ROUTE_PATH_INTF_RX;
2812           break;
2813       case FIB_PATH_TYPE_EXCLUSIVE:
2814         rpath->frp_flags |= FIB_ROUTE_PATH_EXCLUSIVE;
2815       default:
2816         break;
2817     }
2818
2819     if (path_ext && path_ext->fpe_type == FIB_PATH_EXT_MPLS)
2820     {
2821         rpath->frp_label_stack = path_ext->fpe_path.frp_label_stack;
2822     }
2823
2824     if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_DROP)
2825         rpath->frp_flags |= FIB_ROUTE_PATH_DROP;
2826     if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_ICMP_UNREACH)
2827         rpath->frp_flags |= FIB_ROUTE_PATH_ICMP_UNREACH;
2828     if (path->fp_cfg_flags & FIB_PATH_CFG_FLAG_ICMP_PROHIBIT)
2829         rpath->frp_flags |= FIB_ROUTE_PATH_ICMP_PROHIBIT;
2830
2831     return (FIB_PATH_LIST_WALK_CONTINUE);
2832 }
2833
2834 dpo_proto_t
2835 fib_path_get_proto (fib_node_index_t path_index)
2836 {
2837     fib_path_t *path;
2838
2839     path = fib_path_get(path_index);
2840
2841     return (path->fp_nh_proto);
2842 }
2843
2844 void
2845 fib_path_module_init (void)
2846 {
2847     fib_node_register_type (FIB_NODE_TYPE_PATH, &fib_path_vft);
2848     fib_path_logger = vlib_log_register_class ("fib", "path");
2849 }
2850
2851 static clib_error_t *
2852 show_fib_path_command (vlib_main_t * vm,
2853                         unformat_input_t * input,
2854                         vlib_cli_command_t * cmd)
2855 {
2856     fib_node_index_t pi;
2857     fib_path_t *path;
2858
2859     if (unformat (input, "%d", &pi))
2860     {
2861         /*
2862          * show one in detail
2863          */
2864         if (!pool_is_free_index(fib_path_pool, pi))
2865         {
2866             path = fib_path_get(pi);
2867             u8 *s = format(NULL, "%U", format_fib_path, pi, 1,
2868                            FIB_PATH_FORMAT_FLAGS_NONE);
2869             s = format(s, "\n  children:");
2870             s = fib_node_children_format(path->fp_node.fn_children, s);
2871             vlib_cli_output (vm, "%v", s);
2872             vec_free(s);
2873         }
2874         else
2875         {
2876             vlib_cli_output (vm, "path %d invalid", pi);
2877         }
2878     }
2879     else
2880     {
2881         vlib_cli_output (vm, "FIB Paths");
2882         pool_foreach_index (pi, fib_path_pool)
2883          {
2884             vlib_cli_output (vm, "%U", format_fib_path, pi, 0,
2885                              FIB_PATH_FORMAT_FLAGS_NONE);
2886         }
2887     }
2888
2889     return (NULL);
2890 }
2891
2892 VLIB_CLI_COMMAND (show_fib_path, static) = {
2893   .path = "show fib paths",
2894   .function = show_fib_path_command,
2895   .short_help = "show fib paths",
2896 };