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718e3744 | 1 | /* OSPF SPF calculation. |
2 | Copyright (C) 1999, 2000 Kunihiro Ishiguro, Toshiaki Takada | |
3 | ||
4 | This file is part of GNU Zebra. | |
5 | ||
6 | GNU Zebra is free software; you can redistribute it and/or modify it | |
7 | under the terms of the GNU General Public License as published by the | |
8 | Free Software Foundation; either version 2, or (at your option) any | |
9 | later version. | |
10 | ||
11 | GNU Zebra is distributed in the hope that it will be useful, but | |
12 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
14 | General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with GNU Zebra; see the file COPYING. If not, write to the Free | |
18 | Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA | |
19 | 02111-1307, USA. */ | |
20 | ||
21 | #include <zebra.h> | |
22 | ||
23 | #include "thread.h" | |
24 | #include "memory.h" | |
25 | #include "hash.h" | |
26 | #include "linklist.h" | |
27 | #include "prefix.h" | |
28 | #include "if.h" | |
29 | #include "table.h" | |
30 | #include "log.h" | |
31 | #include "sockunion.h" /* for inet_ntop () */ | |
462f20d5 | 32 | #include "pqueue.h" |
718e3744 | 33 | |
34 | #include "ospfd/ospfd.h" | |
35 | #include "ospfd/ospf_interface.h" | |
36 | #include "ospfd/ospf_ism.h" | |
37 | #include "ospfd/ospf_asbr.h" | |
38 | #include "ospfd/ospf_lsa.h" | |
39 | #include "ospfd/ospf_lsdb.h" | |
40 | #include "ospfd/ospf_neighbor.h" | |
41 | #include "ospfd/ospf_nsm.h" | |
42 | #include "ospfd/ospf_spf.h" | |
43 | #include "ospfd/ospf_route.h" | |
44 | #include "ospfd/ospf_ia.h" | |
45 | #include "ospfd/ospf_ase.h" | |
46 | #include "ospfd/ospf_abr.h" | |
47 | #include "ospfd/ospf_dump.h" | |
48 | ||
9c27ef9b PJ |
49 | static void ospf_vertex_free (void *); |
50 | /* List of allocated vertices, to simplify cleanup of SPF. | |
51 | * Not thread-safe obviously. If it ever needs to be, it'd have to be | |
52 | * dynamically allocated at begin of ospf_spf_calculate | |
53 | */ | |
54 | static struct list vertex_list = { .del = ospf_vertex_free }; | |
55 | \f | |
462f20d5 | 56 | /* Heap related functions, for the managment of the candidates, to |
57 | * be used with pqueue. */ | |
58 | static int | |
59 | cmp (void * node1 , void * node2) | |
60 | { | |
61 | struct vertex * v1 = (struct vertex *) node1; | |
62 | struct vertex * v2 = (struct vertex *) node2; | |
63 | if (v1 != NULL && v2 != NULL ) | |
9c27ef9b PJ |
64 | { |
65 | /* network vertices must be chosen before router vertices of same | |
66 | * cost in order to find all shortest paths | |
67 | */ | |
68 | if ( ((v1->distance - v2->distance) == 0) | |
69 | && (v1->type != v2->type)) | |
70 | { | |
71 | switch (v1->type) | |
72 | { | |
73 | case OSPF_VERTEX_NETWORK: | |
74 | return -1; | |
75 | case OSPF_VERTEX_ROUTER: | |
76 | return 1; | |
77 | } | |
78 | } | |
79 | else | |
80 | return (v1->distance - v2->distance); | |
81 | } | |
82 | return 0; | |
462f20d5 | 83 | } |
84 | ||
85 | static void | |
eb3da6df | 86 | update_stat (void *node , int position) |
462f20d5 | 87 | { |
eb3da6df | 88 | struct vertex *v = node; |
89 | ||
462f20d5 | 90 | /* Set the status of the vertex, when its position changes. */ |
91 | *(v->stat) = position; | |
92 | } | |
eb3da6df | 93 | \f |
4dadc291 | 94 | static struct vertex_nexthop * |
eb3da6df | 95 | vertex_nexthop_new (void) |
718e3744 | 96 | { |
eb3da6df | 97 | return XCALLOC (MTYPE_OSPF_NEXTHOP, sizeof (struct vertex_nexthop)); |
718e3744 | 98 | } |
99 | ||
4dadc291 | 100 | static void |
718e3744 | 101 | vertex_nexthop_free (struct vertex_nexthop *nh) |
102 | { | |
103 | XFREE (MTYPE_OSPF_NEXTHOP, nh); | |
104 | } | |
105 | ||
eb3da6df | 106 | /* Free the canonical nexthop objects for an area, ie the nexthop objects |
9c27ef9b PJ |
107 | * attached to the first-hop router vertices, and any intervening network |
108 | * vertices. | |
eb3da6df | 109 | */ |
110 | static void | |
111 | ospf_canonical_nexthops_free (struct vertex *root) | |
718e3744 | 112 | { |
eb3da6df | 113 | struct listnode *node, *nnode; |
114 | struct vertex *child; | |
115 | ||
116 | for (ALL_LIST_ELEMENTS (root->children, node, nnode, child)) | |
117 | { | |
118 | struct listnode *n2, *nn2; | |
119 | struct vertex_parent *vp; | |
120 | ||
58e1befe | 121 | /* router vertices through an attached network each |
122 | * have a distinct (canonical / not inherited) nexthop | |
123 | * which must be freed. | |
124 | * | |
125 | * A network vertex can only have router vertices as its | |
126 | * children, so only one level of recursion is possible. | |
127 | */ | |
eb3da6df | 128 | if (child->type == OSPF_VERTEX_NETWORK) |
129 | ospf_canonical_nexthops_free (child); | |
130 | ||
58e1befe | 131 | /* Free child nexthops pointing back to this root vertex */ |
eb3da6df | 132 | for (ALL_LIST_ELEMENTS (child->parents, n2, nn2, vp)) |
9c27ef9b | 133 | if (vp->parent == root && vp->nexthop) |
58e1befe | 134 | vertex_nexthop_free (vp->nexthop); |
eb3da6df | 135 | } |
136 | } | |
137 | \f | |
9c27ef9b PJ |
138 | /* TODO: Parent list should be excised, in favour of maintaining only |
139 | * vertex_nexthop, with refcounts. | |
140 | */ | |
eb3da6df | 141 | static struct vertex_parent * |
142 | vertex_parent_new (struct vertex *v, int backlink, struct vertex_nexthop *hop) | |
143 | { | |
144 | struct vertex_parent *new; | |
145 | ||
146 | new = XMALLOC (MTYPE_OSPF_VERTEX_PARENT, sizeof (struct vertex_parent)); | |
147 | ||
148 | if (new == NULL) | |
149 | return NULL; | |
150 | ||
151 | new->parent = v; | |
152 | new->backlink = backlink; | |
153 | new->nexthop = hop; | |
718e3744 | 154 | return new; |
155 | } | |
0c0f9cd5 | 156 | |
eb3da6df | 157 | static void |
9c27ef9b | 158 | vertex_parent_free (void *p) |
eb3da6df | 159 | { |
160 | XFREE (MTYPE_OSPF_VERTEX_PARENT, p); | |
161 | } | |
162 | \f | |
4dadc291 | 163 | static struct vertex * |
718e3744 | 164 | ospf_vertex_new (struct ospf_lsa *lsa) |
165 | { | |
166 | struct vertex *new; | |
167 | ||
eb3da6df | 168 | new = XCALLOC (MTYPE_OSPF_VERTEX, sizeof (struct vertex)); |
718e3744 | 169 | |
170 | new->flags = 0; | |
462f20d5 | 171 | new->stat = &(lsa->stat); |
718e3744 | 172 | new->type = lsa->data->type; |
173 | new->id = lsa->data->id; | |
174 | new->lsa = lsa->data; | |
175 | new->distance = 0; | |
eb3da6df | 176 | new->children = list_new (); |
177 | new->parents = list_new (); | |
9c27ef9b PJ |
178 | new->parents->del = vertex_parent_free; |
179 | ||
180 | listnode_add (&vertex_list, new); | |
eb3da6df | 181 | |
9c27ef9b PJ |
182 | if (IS_DEBUG_OSPF_EVENT) |
183 | zlog_debug ("%s: Created %s vertex %s", __func__, | |
184 | new->type == OSPF_VERTEX_ROUTER ? "Router" : "Network", | |
185 | inet_ntoa (new->lsa->id)); | |
718e3744 | 186 | return new; |
187 | } | |
188 | ||
4dadc291 | 189 | static void |
9c27ef9b | 190 | ospf_vertex_free (void *data) |
718e3744 | 191 | { |
9c27ef9b | 192 | struct vertex *v = data; |
eb3da6df | 193 | |
9c27ef9b PJ |
194 | if (IS_DEBUG_OSPF_EVENT) |
195 | zlog_debug ("%s: Free %s vertex %s", __func__, | |
196 | v->type == OSPF_VERTEX_ROUTER ? "Router" : "Network", | |
197 | inet_ntoa (v->lsa->id)); | |
7461d459 | 198 | |
9c27ef9b PJ |
199 | /* There should be no parents potentially holding references to this vertex |
200 | * Children however may still be there, but presumably referenced by other | |
201 | * vertices | |
eb3da6df | 202 | */ |
9c27ef9b | 203 | //assert (listcount (v->parents) == 0); |
eb3da6df | 204 | |
9c27ef9b PJ |
205 | if (v->children) |
206 | list_delete (v->children); | |
207 | v->children = NULL; | |
208 | ||
209 | if (v->parents) | |
210 | list_delete (v->parents); | |
eb3da6df | 211 | v->parents = NULL; |
212 | ||
213 | v->lsa = NULL; | |
7461d459 | 214 | |
718e3744 | 215 | XFREE (MTYPE_OSPF_VERTEX, v); |
216 | } | |
217 | ||
4dadc291 | 218 | static void |
eb1ce605 | 219 | ospf_vertex_dump(const char *msg, struct vertex *v, |
eb3da6df | 220 | int print_parents, int print_children) |
630e4807 | 221 | { |
222 | if ( ! IS_DEBUG_OSPF_EVENT) | |
223 | return; | |
224 | ||
eb3da6df | 225 | zlog_debug("%s %s vertex %s distance %u flags %u", |
630e4807 | 226 | msg, |
227 | v->type == OSPF_VERTEX_ROUTER ? "Router" : "Network", | |
228 | inet_ntoa(v->lsa->id), | |
229 | v->distance, | |
630e4807 | 230 | (unsigned int)v->flags); |
231 | ||
eb3da6df | 232 | if (print_parents) |
630e4807 | 233 | { |
1eb8ef25 | 234 | struct listnode *node; |
eb3da6df | 235 | struct vertex_parent *vp; |
1eb8ef25 | 236 | |
eb3da6df | 237 | for (ALL_LIST_ELEMENTS_RO (v->parents, node, vp)) |
630e4807 | 238 | { |
239 | char buf1[BUFSIZ]; | |
eb3da6df | 240 | |
241 | if (vp) | |
630e4807 | 242 | { |
eb3da6df | 243 | zlog_debug ("parent %s backlink %d nexthop %s interface %s", |
244 | inet_ntoa(vp->parent->lsa->id), vp->backlink, | |
245 | inet_ntop(AF_INET, &vp->nexthop->router, buf1, BUFSIZ), | |
246 | vp->nexthop->oi ? IF_NAME(vp->nexthop->oi) : "NULL"); | |
630e4807 | 247 | } |
248 | } | |
249 | } | |
250 | ||
251 | if (print_children) | |
252 | { | |
52dc7ee6 | 253 | struct listnode *cnode; |
1eb8ef25 | 254 | struct vertex *cv; |
255 | ||
eb3da6df | 256 | for (ALL_LIST_ELEMENTS_RO (v->children, cnode, cv)) |
1eb8ef25 | 257 | ospf_vertex_dump(" child:", cv, 0, 0); |
630e4807 | 258 | } |
259 | } | |
260 | ||
261 | ||
262 | /* Add a vertex to the list of children in each of its parents. */ | |
4dadc291 | 263 | static void |
718e3744 | 264 | ospf_vertex_add_parent (struct vertex *v) |
265 | { | |
eb3da6df | 266 | struct vertex_parent *vp; |
52dc7ee6 | 267 | struct listnode *node; |
7461d459 | 268 | |
9c27ef9b | 269 | assert (v && v->parents); |
7461d459 | 270 | |
eb3da6df | 271 | for (ALL_LIST_ELEMENTS_RO (v->parents, node, vp)) |
718e3744 | 272 | { |
eb3da6df | 273 | assert (vp->parent && vp->parent->children); |
7461d459 | 274 | |
718e3744 | 275 | /* No need to add two links from the same parent. */ |
eb3da6df | 276 | if (listnode_lookup (vp->parent->children, v) == NULL) |
277 | listnode_add (vp->parent->children, v); | |
718e3744 | 278 | } |
279 | } | |
280 | \f | |
4dadc291 | 281 | static void |
718e3744 | 282 | ospf_spf_init (struct ospf_area *area) |
283 | { | |
284 | struct vertex *v; | |
9c27ef9b | 285 | |
718e3744 | 286 | /* Create root node. */ |
287 | v = ospf_vertex_new (area->router_lsa_self); | |
288 | ||
289 | area->spf = v; | |
290 | ||
291 | /* Reset ABR and ASBR router counts. */ | |
292 | area->abr_count = 0; | |
293 | area->asbr_count = 0; | |
294 | } | |
295 | ||
d355bfa7 | 296 | /* return index of link back to V from W, or -1 if no link found */ |
4dadc291 | 297 | static int |
718e3744 | 298 | ospf_lsa_has_link (struct lsa_header *w, struct lsa_header *v) |
299 | { | |
eb1ce605 | 300 | unsigned int i, length; |
718e3744 | 301 | struct router_lsa *rl; |
302 | struct network_lsa *nl; | |
303 | ||
304 | /* In case of W is Network LSA. */ | |
305 | if (w->type == OSPF_NETWORK_LSA) | |
306 | { | |
307 | if (v->type == OSPF_NETWORK_LSA) | |
d355bfa7 | 308 | return -1; |
718e3744 | 309 | |
310 | nl = (struct network_lsa *) w; | |
311 | length = (ntohs (w->length) - OSPF_LSA_HEADER_SIZE - 4) / 4; | |
0c0f9cd5 | 312 | |
718e3744 | 313 | for (i = 0; i < length; i++) |
314 | if (IPV4_ADDR_SAME (&nl->routers[i], &v->id)) | |
d355bfa7 | 315 | return i; |
316 | return -1; | |
718e3744 | 317 | } |
318 | ||
319 | /* In case of W is Router LSA. */ | |
320 | if (w->type == OSPF_ROUTER_LSA) | |
321 | { | |
322 | rl = (struct router_lsa *) w; | |
323 | ||
324 | length = ntohs (w->length); | |
325 | ||
326 | for (i = 0; | |
0c0f9cd5 | 327 | i < ntohs (rl->links) && length >= sizeof (struct router_lsa); |
328 | i++, length -= 12) | |
718e3744 | 329 | { |
330 | switch (rl->link[i].type) | |
331 | { | |
332 | case LSA_LINK_TYPE_POINTOPOINT: | |
333 | case LSA_LINK_TYPE_VIRTUALLINK: | |
334 | /* Router LSA ID. */ | |
335 | if (v->type == OSPF_ROUTER_LSA && | |
336 | IPV4_ADDR_SAME (&rl->link[i].link_id, &v->id)) | |
337 | { | |
d355bfa7 | 338 | return i; |
718e3744 | 339 | } |
340 | break; | |
341 | case LSA_LINK_TYPE_TRANSIT: | |
342 | /* Network LSA ID. */ | |
343 | if (v->type == OSPF_NETWORK_LSA && | |
344 | IPV4_ADDR_SAME (&rl->link[i].link_id, &v->id)) | |
345 | { | |
d355bfa7 | 346 | return i; |
0c0f9cd5 | 347 | } |
718e3744 | 348 | break; |
349 | case LSA_LINK_TYPE_STUB: | |
eb3da6df | 350 | /* Stub can't lead anywhere, carry on */ |
718e3744 | 351 | continue; |
352 | default: | |
353 | break; | |
354 | } | |
355 | } | |
356 | } | |
d355bfa7 | 357 | return -1; |
718e3744 | 358 | } |
359 | ||
718e3744 | 360 | #define ROUTER_LSA_MIN_SIZE 12 |
361 | #define ROUTER_LSA_TOS_SIZE 4 | |
362 | ||
630e4807 | 363 | /* Find the next link after prev_link from v to w. If prev_link is |
364 | * NULL, return the first link from v to w. Ignore stub and virtual links; | |
365 | * these link types will never be returned. | |
366 | */ | |
4dadc291 | 367 | static struct router_lsa_link * |
718e3744 | 368 | ospf_get_next_link (struct vertex *v, struct vertex *w, |
0c0f9cd5 | 369 | struct router_lsa_link *prev_link) |
718e3744 | 370 | { |
371 | u_char *p; | |
372 | u_char *lim; | |
373 | struct router_lsa_link *l; | |
374 | ||
375 | if (prev_link == NULL) | |
630e4807 | 376 | p = ((u_char *) v->lsa) + OSPF_LSA_HEADER_SIZE + 4; |
718e3744 | 377 | else |
378 | { | |
0c0f9cd5 | 379 | p = (u_char *) prev_link; |
718e3744 | 380 | p += (ROUTER_LSA_MIN_SIZE + |
381 | (prev_link->m[0].tos_count * ROUTER_LSA_TOS_SIZE)); | |
382 | } | |
0c0f9cd5 | 383 | |
718e3744 | 384 | lim = ((u_char *) v->lsa) + ntohs (v->lsa->length); |
385 | ||
386 | while (p < lim) | |
387 | { | |
388 | l = (struct router_lsa_link *) p; | |
389 | ||
0c0f9cd5 | 390 | p += (ROUTER_LSA_MIN_SIZE + (l->m[0].tos_count * ROUTER_LSA_TOS_SIZE)); |
718e3744 | 391 | |
392 | if (l->m[0].type == LSA_LINK_TYPE_STUB) | |
393 | continue; | |
394 | ||
395 | /* Defer NH calculation via VLs until summaries from | |
396 | transit areas area confidered */ | |
397 | ||
398 | if (l->m[0].type == LSA_LINK_TYPE_VIRTUALLINK) | |
0c0f9cd5 | 399 | continue; |
718e3744 | 400 | |
401 | if (IPV4_ADDR_SAME (&l->link_id, &w->id)) | |
0c0f9cd5 | 402 | return l; |
718e3744 | 403 | } |
404 | ||
405 | return NULL; | |
406 | } | |
407 | ||
bc20c1a4 PJ |
408 | static void |
409 | ospf_spf_flush_parents (struct vertex *w) | |
410 | { | |
411 | struct vertex_parent *vp; | |
412 | struct listnode *ln, *nn; | |
413 | ||
414 | /* delete the existing nexthops */ | |
415 | for (ALL_LIST_ELEMENTS (w->parents, ln, nn, vp)) | |
416 | { | |
417 | list_delete_node (w->parents, ln); | |
418 | vertex_parent_free (vp); | |
419 | } | |
420 | } | |
421 | ||
75ee0b8e | 422 | /* |
423 | * Consider supplied next-hop for inclusion to the supplied list of | |
424 | * equal-cost next-hops, adjust list as neccessary. | |
bf9392c6 | 425 | */ |
4dadc291 | 426 | static void |
eb3da6df | 427 | ospf_spf_add_parent (struct vertex *v, struct vertex *w, |
bc20c1a4 PJ |
428 | struct vertex_nexthop *newhop, |
429 | struct router_lsa_link *l) | |
bf9392c6 | 430 | { |
eb3da6df | 431 | struct vertex_parent *vp; |
bc20c1a4 | 432 | unsigned int new_distance; |
eb3da6df | 433 | |
434 | /* we must have a newhop.. */ | |
bc20c1a4 PJ |
435 | assert (v && w && l && newhop); |
436 | ||
437 | new_distance = v->distance + ntohs (l->m[0].metric); | |
eb3da6df | 438 | |
bc20c1a4 PJ |
439 | /* We shouldn't get here unless callers have determined V(l)->W is |
440 | * shortest / equal-shortest path. | |
441 | */ | |
442 | assert (new_distance <= w->distance); | |
443 | ||
444 | /* Adding parent for a new, better path: flush existing parents from W. */ | |
445 | if (new_distance < w->distance) | |
446 | { | |
447 | ospf_spf_flush_parents (w); | |
448 | w->distance = new_distance; | |
449 | } | |
450 | ||
451 | /* new parent is <= existing parents, add it to parent list */ | |
eb3da6df | 452 | vp = vertex_parent_new (v, ospf_lsa_has_link (w->lsa, v->lsa), newhop); |
453 | listnode_add (w->parents, vp); | |
0c0f9cd5 | 454 | |
eb3da6df | 455 | return; |
456 | } | |
457 | ||
630e4807 | 458 | /* 16.1.1. Calculate nexthop from root through V (parent) to |
459 | * vertex W (destination). | |
eb3da6df | 460 | * |
461 | * The link must be supplied if V is the root vertex. In all other cases | |
462 | * it may be NULL. | |
630e4807 | 463 | */ |
bc20c1a4 | 464 | static unsigned int |
eb3da6df | 465 | ospf_nexthop_calculation (struct ospf_area *area, struct vertex *v, |
466 | struct vertex *w, struct router_lsa_link *l) | |
718e3744 | 467 | { |
1eb8ef25 | 468 | struct listnode *node, *nnode; |
eb3da6df | 469 | struct vertex_nexthop *nh; |
470 | struct vertex_parent *vp; | |
718e3744 | 471 | struct ospf_interface *oi = NULL; |
bc20c1a4 | 472 | unsigned int added = 0; |
0c0f9cd5 | 473 | |
718e3744 | 474 | if (IS_DEBUG_OSPF_EVENT) |
630e4807 | 475 | { |
2a42e285 | 476 | zlog_debug ("ospf_nexthop_calculation(): Start"); |
630e4807 | 477 | ospf_vertex_dump("V (parent):", v, 1, 1); |
478 | ospf_vertex_dump("W (dest) :", w, 1, 1); | |
479 | } | |
718e3744 | 480 | |
718e3744 | 481 | if (v == area->spf) |
9c27ef9b | 482 | { |
630e4807 | 483 | /* 16.1.1 para 4. In the first case, the parent vertex (V) is the |
484 | root (the calculating router itself). This means that the | |
485 | destination is either a directly connected network or directly | |
486 | connected router. The outgoing interface in this case is simply | |
487 | the OSPF interface connecting to the destination network/router. | |
488 | */ | |
489 | ||
718e3744 | 490 | if (w->type == OSPF_VERTEX_ROUTER) |
0c0f9cd5 | 491 | { |
eb3da6df | 492 | /* l is a link from v to w |
493 | * l2 will be link from w to v | |
494 | */ | |
495 | struct router_lsa_link *l2 = NULL; | |
496 | ||
497 | /* we *must* be supplied with the link data */ | |
498 | assert (l != NULL); | |
499 | ||
500 | if (IS_DEBUG_OSPF_EVENT) | |
0c0f9cd5 | 501 | { |
eb3da6df | 502 | char buf1[BUFSIZ]; |
503 | char buf2[BUFSIZ]; | |
504 | ||
505 | zlog_debug("ospf_nexthop_calculation(): considering link " | |
506 | "type %d link_id %s link_data %s", | |
507 | l->m[0].type, | |
508 | inet_ntop (AF_INET, &l->link_id, buf1, BUFSIZ), | |
509 | inet_ntop (AF_INET, &l->link_data, buf2, BUFSIZ)); | |
510 | } | |
511 | ||
512 | if (l->m[0].type == LSA_LINK_TYPE_POINTOPOINT) | |
513 | { | |
514 | /* If the destination is a router which connects to | |
515 | the calculating router via a Point-to-MultiPoint | |
516 | network, the destination's next hop IP address(es) | |
517 | can be determined by examining the destination's | |
518 | router-LSA: each link pointing back to the | |
519 | calculating router and having a Link Data field | |
520 | belonging to the Point-to-MultiPoint network | |
521 | provides an IP address of the next hop router. | |
522 | ||
523 | At this point l is a link from V to W, and V is the | |
524 | root ("us"). Find the local interface associated | |
525 | with l (its address is in l->link_data). If it | |
526 | is a point-to-multipoint interface, then look through | |
527 | the links in the opposite direction (W to V). If | |
528 | any of them have an address that lands within the | |
529 | subnet declared by the PtMP link, then that link | |
530 | is a constituent of the PtMP link, and its address is | |
531 | a nexthop address for V. | |
532 | */ | |
533 | oi = ospf_if_is_configured (area->ospf, &l->link_data); | |
534 | if (oi && oi->type == OSPF_IFTYPE_POINTOMULTIPOINT) | |
0c0f9cd5 | 535 | { |
eb3da6df | 536 | struct prefix_ipv4 la; |
537 | ||
538 | la.family = AF_INET; | |
539 | la.prefixlen = oi->address->prefixlen; | |
540 | ||
541 | /* V links to W on PtMP interface | |
542 | - find the interface address on W */ | |
543 | while ((l2 = ospf_get_next_link (w, v, l2))) | |
0c0f9cd5 | 544 | { |
eb3da6df | 545 | la.prefix = l2->link_data; |
0c0f9cd5 | 546 | |
eb3da6df | 547 | if (prefix_cmp ((struct prefix *) &la, |
548 | oi->address) == 0) | |
549 | /* link_data is on our PtMP network */ | |
550 | break; | |
551 | } | |
552 | } /* end l is on point-to-multipoint link */ | |
553 | else | |
554 | { | |
555 | /* l is a regular point-to-point link. | |
556 | Look for a link from W to V. | |
557 | */ | |
558 | while ((l2 = ospf_get_next_link (w, v, l2))) | |
0c0f9cd5 | 559 | { |
eb3da6df | 560 | oi = ospf_if_is_configured (area->ospf, |
561 | &(l2->link_data)); | |
562 | ||
563 | if (oi == NULL) | |
564 | continue; | |
565 | ||
566 | if (!IPV4_ADDR_SAME (&oi->address->u.prefix4, | |
567 | &l->link_data)) | |
568 | continue; | |
569 | ||
570 | break; | |
0c0f9cd5 | 571 | } |
eb3da6df | 572 | } |
573 | ||
574 | if (oi && l2) | |
575 | { | |
576 | /* found all necessary info to build nexthop */ | |
577 | nh = vertex_nexthop_new (); | |
578 | nh->oi = oi; | |
579 | nh->router = l2->link_data; | |
bc20c1a4 PJ |
580 | ospf_spf_add_parent (v, w, nh, l); |
581 | return 1; | |
eb3da6df | 582 | } |
583 | else | |
9c27ef9b PJ |
584 | zlog_info("ospf_nexthop_calculation(): " |
585 | "could not determine nexthop for link"); | |
586 | } /* end point-to-point link from V to W */ | |
587 | else if (l->m[0].type == LSA_LINK_TYPE_VIRTUALLINK) | |
588 | { | |
589 | struct ospf_vl_data *vl_data; | |
590 | ||
591 | /* VLink implementation limitations: | |
592 | * a) vl_data can only reference one nexthop, so no ECMP | |
593 | * to backbone through VLinks. Though transit-area | |
594 | * summaries may be considered, and those can be ECMP. | |
595 | * b) We can only use /one/ VLink, even if multiple ones | |
596 | * exist this router through multiple transit-areas. | |
597 | */ | |
598 | vl_data = ospf_vl_lookup (area->ospf, NULL, l->link_id); | |
599 | ||
600 | if (vl_data | |
601 | && CHECK_FLAG (vl_data->flags, OSPF_VL_FLAG_APPROVED)) | |
eb3da6df | 602 | { |
9c27ef9b PJ |
603 | nh = vertex_nexthop_new (); |
604 | nh->oi = vl_data->nexthop.oi; | |
605 | nh->router = vl_data->nexthop.router; | |
bc20c1a4 PJ |
606 | ospf_spf_add_parent (v, w, nh, l); |
607 | return 1; | |
eb3da6df | 608 | } |
9c27ef9b | 609 | else |
bc20c1a4 PJ |
610 | zlog_info("ospf_nexthop_calculation(): " |
611 | "vl_data for VL link not found"); | |
9c27ef9b | 612 | } /* end virtual-link from V to W */ |
bc20c1a4 | 613 | return 0; |
630e4807 | 614 | } /* end W is a Router vertex */ |
718e3744 | 615 | else |
0c0f9cd5 | 616 | { |
eb3da6df | 617 | assert(w->type == OSPF_VERTEX_NETWORK); |
618 | oi = ospf_if_is_configured (area->ospf, &(l->link_data)); | |
619 | if (oi) | |
0c0f9cd5 | 620 | { |
eb3da6df | 621 | nh = vertex_nexthop_new (); |
622 | nh->oi = oi; | |
623 | nh->router.s_addr = 0; | |
bc20c1a4 PJ |
624 | ospf_spf_add_parent (v, w, nh, l); |
625 | return 1; | |
0c0f9cd5 | 626 | } |
627 | } | |
9c27ef9b PJ |
628 | zlog_info("ospf_nexthop_calculation(): " |
629 | "Unknown attached link"); | |
bc20c1a4 | 630 | return 0; |
630e4807 | 631 | } /* end V is the root */ |
630e4807 | 632 | /* Check if W's parent is a network connected to root. */ |
718e3744 | 633 | else if (v->type == OSPF_VERTEX_NETWORK) |
634 | { | |
630e4807 | 635 | /* See if any of V's parents are the root. */ |
eb3da6df | 636 | for (ALL_LIST_ELEMENTS (v->parents, node, nnode, vp)) |
718e3744 | 637 | { |
eb3da6df | 638 | if (vp->parent == area->spf) /* connects to root? */ |
630e4807 | 639 | { |
640 | /* 16.1.1 para 5. ...the parent vertex is a network that | |
641 | * directly connects the calculating router to the destination | |
642 | * router. The list of next hops is then determined by | |
643 | * examining the destination's router-LSA... | |
644 | */ | |
645 | ||
646 | assert(w->type == OSPF_VERTEX_ROUTER); | |
0c0f9cd5 | 647 | while ((l = ospf_get_next_link (w, v, l))) |
648 | { | |
630e4807 | 649 | /* ...For each link in the router-LSA that points back to the |
650 | * parent network, the link's Link Data field provides the IP | |
651 | * address of a next hop router. The outgoing interface to | |
652 | * use can then be derived from the next hop IP address (or | |
653 | * it can be inherited from the parent network). | |
654 | */ | |
eb3da6df | 655 | nh = vertex_nexthop_new (); |
656 | nh->oi = vp->nexthop->oi; | |
657 | nh->router = l->link_data; | |
bc20c1a4 PJ |
658 | added = 1; |
659 | ospf_spf_add_parent (v, w, nh, l); | |
0c0f9cd5 | 660 | } |
0c0f9cd5 | 661 | } |
718e3744 | 662 | } |
bc20c1a4 | 663 | return added; |
718e3744 | 664 | } |
665 | ||
630e4807 | 666 | /* 16.1.1 para 4. If there is at least one intervening router in the |
667 | * current shortest path between the destination and the root, the | |
668 | * destination simply inherits the set of next hops from the | |
669 | * parent. | |
670 | */ | |
eb3da6df | 671 | for (ALL_LIST_ELEMENTS (v->parents, node, nnode, vp)) |
bc20c1a4 PJ |
672 | { |
673 | added = 1; | |
674 | ospf_spf_add_parent (v, w, vp->nexthop, l); | |
675 | } | |
9c27ef9b | 676 | |
bc20c1a4 | 677 | return added; |
718e3744 | 678 | } |
679 | ||
630e4807 | 680 | /* RFC2328 Section 16.1 (2). |
681 | * v is on the SPF tree. Examine the links in v's LSA. Update the list | |
682 | * of candidates with any vertices not already on the list. If a lower-cost | |
683 | * path is found to a vertex already on the candidate list, store the new cost. | |
684 | */ | |
4dadc291 | 685 | static void |
718e3744 | 686 | ospf_spf_next (struct vertex *v, struct ospf_area *area, |
462f20d5 | 687 | struct pqueue * candidate) |
718e3744 | 688 | { |
689 | struct ospf_lsa *w_lsa = NULL; | |
718e3744 | 690 | u_char *p; |
691 | u_char *lim; | |
692 | struct router_lsa_link *l = NULL; | |
693 | struct in_addr *r; | |
718e3744 | 694 | int type = 0; |
695 | ||
696 | /* If this is a router-LSA, and bit V of the router-LSA (see Section | |
697 | A.4.2:RFC2328) is set, set Area A's TransitCapability to TRUE. */ | |
698 | if (v->type == OSPF_VERTEX_ROUTER) | |
699 | { | |
700 | if (IS_ROUTER_LSA_VIRTUAL ((struct router_lsa *) v->lsa)) | |
701 | area->transit = OSPF_TRANSIT_TRUE; | |
702 | } | |
703 | ||
704 | p = ((u_char *) v->lsa) + OSPF_LSA_HEADER_SIZE + 4; | |
0c0f9cd5 | 705 | lim = ((u_char *) v->lsa) + ntohs (v->lsa->length); |
706 | ||
718e3744 | 707 | while (p < lim) |
708 | { | |
eb3da6df | 709 | struct vertex *w; |
710 | unsigned int distance; | |
d355bfa7 | 711 | |
718e3744 | 712 | /* In case of V is Router-LSA. */ |
713 | if (v->lsa->type == OSPF_ROUTER_LSA) | |
714 | { | |
715 | l = (struct router_lsa_link *) p; | |
716 | ||
0c0f9cd5 | 717 | p += (ROUTER_LSA_MIN_SIZE + |
718e3744 | 718 | (l->m[0].tos_count * ROUTER_LSA_TOS_SIZE)); |
719 | ||
720 | /* (a) If this is a link to a stub network, examine the next | |
721 | link in V's LSA. Links to stub networks will be | |
722 | considered in the second stage of the shortest path | |
723 | calculation. */ | |
724 | if ((type = l->m[0].type) == LSA_LINK_TYPE_STUB) | |
725 | continue; | |
726 | ||
727 | /* (b) Otherwise, W is a transit vertex (router or transit | |
728 | network). Look up the vertex W's LSA (router-LSA or | |
729 | network-LSA) in Area A's link state database. */ | |
730 | switch (type) | |
731 | { | |
732 | case LSA_LINK_TYPE_POINTOPOINT: | |
733 | case LSA_LINK_TYPE_VIRTUALLINK: | |
734 | if (type == LSA_LINK_TYPE_VIRTUALLINK) | |
0c0f9cd5 | 735 | { |
736 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 737 | zlog_debug ("looking up LSA through VL: %s", |
0c0f9cd5 | 738 | inet_ntoa (l->link_id)); |
739 | } | |
718e3744 | 740 | |
741 | w_lsa = ospf_lsa_lookup (area, OSPF_ROUTER_LSA, l->link_id, | |
742 | l->link_id); | |
743 | if (w_lsa) | |
0c0f9cd5 | 744 | { |
745 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 746 | zlog_debug ("found Router LSA %s", inet_ntoa (l->link_id)); |
0c0f9cd5 | 747 | } |
718e3744 | 748 | break; |
749 | case LSA_LINK_TYPE_TRANSIT: | |
0c0f9cd5 | 750 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 751 | zlog_debug ("Looking up Network LSA, ID: %s", |
0c0f9cd5 | 752 | inet_ntoa (l->link_id)); |
718e3744 | 753 | w_lsa = ospf_lsa_lookup_by_id (area, OSPF_NETWORK_LSA, |
0c0f9cd5 | 754 | l->link_id); |
718e3744 | 755 | if (w_lsa) |
0c0f9cd5 | 756 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 757 | zlog_debug ("found the LSA"); |
718e3744 | 758 | break; |
759 | default: | |
0c0f9cd5 | 760 | zlog_warn ("Invalid LSA link type %d", type); |
718e3744 | 761 | continue; |
762 | } | |
763 | } | |
764 | else | |
765 | { | |
766 | /* In case of V is Network-LSA. */ | |
0c0f9cd5 | 767 | r = (struct in_addr *) p; |
718e3744 | 768 | p += sizeof (struct in_addr); |
769 | ||
770 | /* Lookup the vertex W's LSA. */ | |
771 | w_lsa = ospf_lsa_lookup_by_id (area, OSPF_ROUTER_LSA, *r); | |
772 | } | |
773 | ||
774 | /* (b cont.) If the LSA does not exist, or its LS age is equal | |
775 | to MaxAge, or it does not have a link back to vertex V, | |
776 | examine the next link in V's LSA.[23] */ | |
777 | if (w_lsa == NULL) | |
778 | continue; | |
779 | ||
780 | if (IS_LSA_MAXAGE (w_lsa)) | |
781 | continue; | |
782 | ||
eb3da6df | 783 | if (ospf_lsa_has_link (w_lsa->data, v->lsa) < 0 ) |
718e3744 | 784 | { |
0c0f9cd5 | 785 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 786 | zlog_debug ("The LSA doesn't have a link back"); |
718e3744 | 787 | continue; |
788 | } | |
789 | ||
790 | /* (c) If vertex W is already on the shortest-path tree, examine | |
791 | the next link in the LSA. */ | |
462f20d5 | 792 | if (w_lsa->stat == LSA_SPF_IN_SPFTREE) |
793 | { | |
794 | if (IS_DEBUG_OSPF_EVENT) | |
795 | zlog_debug ("The LSA is already in SPF"); | |
796 | continue; | |
797 | } | |
718e3744 | 798 | |
799 | /* (d) Calculate the link state cost D of the resulting path | |
800 | from the root to vertex W. D is equal to the sum of the link | |
801 | state cost of the (already calculated) shortest path to | |
802 | vertex V and the advertised cost of the link between vertices | |
803 | V and W. If D is: */ | |
804 | ||
718e3744 | 805 | /* calculate link cost D. */ |
806 | if (v->lsa->type == OSPF_ROUTER_LSA) | |
eb3da6df | 807 | distance = v->distance + ntohs (l->m[0].metric); |
630e4807 | 808 | else /* v is not a Router-LSA */ |
eb3da6df | 809 | distance = v->distance; |
718e3744 | 810 | |
811 | /* Is there already vertex W in candidate list? */ | |
462f20d5 | 812 | if (w_lsa->stat == LSA_SPF_NOT_EXPLORED) |
813 | { | |
eb3da6df | 814 | /* prepare vertex W. */ |
815 | w = ospf_vertex_new (w_lsa); | |
bc20c1a4 | 816 | w->distance = distance; |
eb3da6df | 817 | |
462f20d5 | 818 | /* Calculate nexthop to W. */ |
bc20c1a4 PJ |
819 | if (ospf_nexthop_calculation (area, v, w, l)) |
820 | pqueue_enqueue (w, candidate); | |
462f20d5 | 821 | } |
822 | else if (w_lsa->stat >= 0) | |
823 | { | |
824 | /* Get the vertex from candidates. */ | |
eb3da6df | 825 | w = candidate->array[w_lsa->stat]; |
718e3744 | 826 | |
462f20d5 | 827 | /* if D is greater than. */ |
eb3da6df | 828 | if (w->distance < distance) |
718e3744 | 829 | { |
718e3744 | 830 | continue; |
831 | } | |
462f20d5 | 832 | /* equal to. */ |
eb3da6df | 833 | else if (w->distance == distance) |
718e3744 | 834 | { |
eb3da6df | 835 | /* Found an equal-cost path to W. |
836 | * Calculate nexthop of to W from V. */ | |
837 | ospf_nexthop_calculation (area, v, w, l); | |
718e3744 | 838 | } |
462f20d5 | 839 | /* less than. */ |
840 | else | |
718e3744 | 841 | { |
bc20c1a4 PJ |
842 | /* Found a lower-cost path to W. |
843 | * nexthop_calculation is conditional, if it finds | |
844 | * valid nexthop it will call spf_add_parents, which | |
845 | * will flush the old parents | |
846 | */ | |
847 | if (ospf_nexthop_calculation (area, v, w, l)) | |
848 | /* Decrease the key of the node in the heap, | |
849 | * re-sort the heap. */ | |
850 | trickle_down (w_lsa->stat, candidate); | |
718e3744 | 851 | } |
630e4807 | 852 | } /* end W is already on the candidate list */ |
853 | } /* end loop over the links in V's LSA */ | |
718e3744 | 854 | } |
855 | ||
4dadc291 | 856 | static void |
718e3744 | 857 | ospf_spf_dump (struct vertex *v, int i) |
858 | { | |
52dc7ee6 | 859 | struct listnode *cnode; |
860 | struct listnode *nnode; | |
eb3da6df | 861 | struct vertex_parent *parent; |
718e3744 | 862 | |
863 | if (v->type == OSPF_VERTEX_ROUTER) | |
864 | { | |
865 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 866 | zlog_debug ("SPF Result: %d [R] %s", i, inet_ntoa (v->lsa->id)); |
718e3744 | 867 | } |
868 | else | |
869 | { | |
870 | struct network_lsa *lsa = (struct network_lsa *) v->lsa; | |
871 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 872 | zlog_debug ("SPF Result: %d [N] %s/%d", i, inet_ntoa (v->lsa->id), |
0c0f9cd5 | 873 | ip_masklen (lsa->mask)); |
630e4807 | 874 | } |
718e3744 | 875 | |
1eb8ef25 | 876 | if (IS_DEBUG_OSPF_EVENT) |
eb3da6df | 877 | for (ALL_LIST_ELEMENTS_RO (v->parents, nnode, parent)) |
878 | { | |
879 | zlog_debug (" nexthop %p %s %s", | |
880 | parent->nexthop, | |
881 | inet_ntoa (parent->nexthop->router), | |
882 | parent->nexthop->oi ? IF_NAME(parent->nexthop->oi) | |
883 | : "NULL"); | |
884 | } | |
718e3744 | 885 | |
886 | i++; | |
887 | ||
eb3da6df | 888 | for (ALL_LIST_ELEMENTS_RO (v->children, cnode, v)) |
1eb8ef25 | 889 | ospf_spf_dump (v, i); |
718e3744 | 890 | } |
891 | ||
892 | /* Second stage of SPF calculation. */ | |
4dadc291 | 893 | static void |
0c0f9cd5 | 894 | ospf_spf_process_stubs (struct ospf_area *area, struct vertex *v, |
718e3744 | 895 | struct route_table *rt) |
896 | { | |
1eb8ef25 | 897 | struct listnode *cnode, *cnnode; |
718e3744 | 898 | struct vertex *child; |
899 | ||
900 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 901 | zlog_debug ("ospf_process_stub():processing stubs for area %s", |
0c0f9cd5 | 902 | inet_ntoa (area->area_id)); |
718e3744 | 903 | if (v->type == OSPF_VERTEX_ROUTER) |
904 | { | |
905 | u_char *p; | |
906 | u_char *lim; | |
907 | struct router_lsa_link *l; | |
908 | struct router_lsa *rlsa; | |
909 | ||
0c0f9cd5 | 910 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 911 | zlog_debug ("ospf_process_stubs():processing router LSA, id: %s", |
0c0f9cd5 | 912 | inet_ntoa (v->lsa->id)); |
718e3744 | 913 | rlsa = (struct router_lsa *) v->lsa; |
914 | ||
915 | ||
0c0f9cd5 | 916 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 917 | zlog_debug ("ospf_process_stubs(): we have %d links to process", |
0c0f9cd5 | 918 | ntohs (rlsa->links)); |
630e4807 | 919 | p = ((u_char *) v->lsa) + OSPF_LSA_HEADER_SIZE + 4; |
718e3744 | 920 | lim = ((u_char *) v->lsa) + ntohs (v->lsa->length); |
921 | ||
922 | while (p < lim) | |
923 | { | |
924 | l = (struct router_lsa_link *) p; | |
925 | ||
926 | p += (ROUTER_LSA_MIN_SIZE + | |
927 | (l->m[0].tos_count * ROUTER_LSA_TOS_SIZE)); | |
928 | ||
929 | if (l->m[0].type == LSA_LINK_TYPE_STUB) | |
930 | ospf_intra_add_stub (rt, l, v, area); | |
931 | } | |
932 | } | |
933 | ||
630e4807 | 934 | ospf_vertex_dump("ospf_process_stubs(): after examining links: ", v, 1, 1); |
718e3744 | 935 | |
eb3da6df | 936 | for (ALL_LIST_ELEMENTS (v->children, cnode, cnnode, child)) |
718e3744 | 937 | { |
718e3744 | 938 | if (CHECK_FLAG (child->flags, OSPF_VERTEX_PROCESSED)) |
0c0f9cd5 | 939 | continue; |
718e3744 | 940 | |
941 | ospf_spf_process_stubs (area, child, rt); | |
942 | ||
943 | SET_FLAG (child->flags, OSPF_VERTEX_PROCESSED); | |
944 | } | |
945 | } | |
946 | ||
947 | void | |
948 | ospf_rtrs_free (struct route_table *rtrs) | |
949 | { | |
950 | struct route_node *rn; | |
52dc7ee6 | 951 | struct list *or_list; |
1eb8ef25 | 952 | struct ospf_route *or; |
953 | struct listnode *node, *nnode; | |
718e3744 | 954 | |
955 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 956 | zlog_debug ("Route: Router Routing Table free"); |
718e3744 | 957 | |
958 | for (rn = route_top (rtrs); rn; rn = route_next (rn)) | |
959 | if ((or_list = rn->info) != NULL) | |
960 | { | |
1eb8ef25 | 961 | for (ALL_LIST_ELEMENTS (or_list, node, nnode, or)) |
962 | ospf_route_free (or); | |
718e3744 | 963 | |
0c0f9cd5 | 964 | list_delete (or_list); |
718e3744 | 965 | |
0c0f9cd5 | 966 | /* Unlock the node. */ |
967 | rn->info = NULL; | |
968 | route_unlock_node (rn); | |
718e3744 | 969 | } |
970 | route_table_finish (rtrs); | |
971 | } | |
972 | ||
4dadc291 | 973 | static void |
718e3744 | 974 | ospf_rtrs_print (struct route_table *rtrs) |
975 | { | |
976 | struct route_node *rn; | |
52dc7ee6 | 977 | struct list *or_list; |
978 | struct listnode *ln; | |
979 | struct listnode *pnode; | |
718e3744 | 980 | struct ospf_route *or; |
981 | struct ospf_path *path; | |
982 | char buf1[BUFSIZ]; | |
983 | char buf2[BUFSIZ]; | |
984 | ||
985 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 986 | zlog_debug ("ospf_rtrs_print() start"); |
718e3744 | 987 | |
988 | for (rn = route_top (rtrs); rn; rn = route_next (rn)) | |
989 | if ((or_list = rn->info) != NULL) | |
1eb8ef25 | 990 | for (ALL_LIST_ELEMENTS_RO (or_list, ln, or)) |
718e3744 | 991 | { |
718e3744 | 992 | switch (or->path_type) |
993 | { | |
994 | case OSPF_PATH_INTRA_AREA: | |
0c0f9cd5 | 995 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 996 | zlog_debug ("%s [%d] area: %s", |
0c0f9cd5 | 997 | inet_ntop (AF_INET, &or->id, buf1, BUFSIZ), |
998 | or->cost, inet_ntop (AF_INET, &or->u.std.area_id, | |
999 | buf2, BUFSIZ)); | |
718e3744 | 1000 | break; |
1001 | case OSPF_PATH_INTER_AREA: | |
0c0f9cd5 | 1002 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 1003 | zlog_debug ("%s IA [%d] area: %s", |
0c0f9cd5 | 1004 | inet_ntop (AF_INET, &or->id, buf1, BUFSIZ), |
1005 | or->cost, inet_ntop (AF_INET, &or->u.std.area_id, | |
1006 | buf2, BUFSIZ)); | |
718e3744 | 1007 | break; |
1008 | default: | |
1009 | break; | |
1010 | } | |
1011 | ||
1eb8ef25 | 1012 | for (ALL_LIST_ELEMENTS_RO (or->paths, pnode, path)) |
718e3744 | 1013 | { |
718e3744 | 1014 | if (path->nexthop.s_addr == 0) |
0c0f9cd5 | 1015 | { |
1016 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1017 | zlog_debug (" directly attached to %s\r\n", |
0c0f9cd5 | 1018 | IF_NAME (path->oi)); |
1019 | } | |
1020 | else | |
1021 | { | |
1022 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1023 | zlog_debug (" via %s, %s\r\n", |
0c0f9cd5 | 1024 | inet_ntoa (path->nexthop), IF_NAME (path->oi)); |
1025 | } | |
718e3744 | 1026 | } |
1027 | } | |
1028 | ||
2a42e285 | 1029 | zlog_debug ("ospf_rtrs_print() end"); |
718e3744 | 1030 | } |
1031 | ||
1032 | /* Calculating the shortest-path tree for an area. */ | |
4dadc291 | 1033 | static void |
0c0f9cd5 | 1034 | ospf_spf_calculate (struct ospf_area *area, struct route_table *new_table, |
718e3744 | 1035 | struct route_table *new_rtrs) |
1036 | { | |
462f20d5 | 1037 | struct pqueue *candidate; |
718e3744 | 1038 | struct vertex *v; |
eb3da6df | 1039 | |
718e3744 | 1040 | if (IS_DEBUG_OSPF_EVENT) |
1041 | { | |
2a42e285 | 1042 | zlog_debug ("ospf_spf_calculate: Start"); |
1043 | zlog_debug ("ospf_spf_calculate: running Dijkstra for area %s", | |
0c0f9cd5 | 1044 | inet_ntoa (area->area_id)); |
718e3744 | 1045 | } |
1046 | ||
1047 | /* Check router-lsa-self. If self-router-lsa is not yet allocated, | |
1048 | return this area's calculation. */ | |
0c0f9cd5 | 1049 | if (!area->router_lsa_self) |
718e3744 | 1050 | { |
1051 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1052 | zlog_debug ("ospf_spf_calculate: " |
0c0f9cd5 | 1053 | "Skip area %s's calculation due to empty router_lsa_self", |
1054 | inet_ntoa (area->area_id)); | |
718e3744 | 1055 | return; |
1056 | } | |
1057 | ||
1058 | /* RFC2328 16.1. (1). */ | |
0c0f9cd5 | 1059 | /* Initialize the algorithm's data structures. */ |
462f20d5 | 1060 | |
1061 | /* This function scans all the LSA database and set the stat field to | |
1062 | * LSA_SPF_NOT_EXPLORED. */ | |
1063 | ospf_lsdb_clean_stat (area->lsdb); | |
1064 | /* Create a new heap for the candidates. */ | |
1065 | candidate = pqueue_create(); | |
1066 | candidate->cmp = cmp; | |
1067 | candidate->update = update_stat; | |
718e3744 | 1068 | |
1069 | /* Initialize the shortest-path tree to only the root (which is the | |
1070 | router doing the calculation). */ | |
1071 | ospf_spf_init (area); | |
1072 | v = area->spf; | |
462f20d5 | 1073 | /* Set LSA position to LSA_SPF_IN_SPFTREE. This vertex is the root of the |
1074 | * spanning tree. */ | |
1075 | *(v->stat) = LSA_SPF_IN_SPFTREE; | |
718e3744 | 1076 | |
1077 | /* Set Area A's TransitCapability to FALSE. */ | |
1078 | area->transit = OSPF_TRANSIT_FALSE; | |
1079 | area->shortcut_capability = 1; | |
eb3da6df | 1080 | |
718e3744 | 1081 | for (;;) |
1082 | { | |
1083 | /* RFC2328 16.1. (2). */ | |
462f20d5 | 1084 | ospf_spf_next (v, area, candidate); |
718e3744 | 1085 | |
1086 | /* RFC2328 16.1. (3). */ | |
1087 | /* If at this step the candidate list is empty, the shortest- | |
1088 | path tree (of transit vertices) has been completely built and | |
1089 | this stage of the procedure terminates. */ | |
462f20d5 | 1090 | if (candidate->size == 0) |
718e3744 | 1091 | break; |
1092 | ||
1093 | /* Otherwise, choose the vertex belonging to the candidate list | |
1094 | that is closest to the root, and add it to the shortest-path | |
1095 | tree (removing it from the candidate list in the | |
0c0f9cd5 | 1096 | process). */ |
462f20d5 | 1097 | /* Extract from the candidates the node with the lower key. */ |
1098 | v = (struct vertex *) pqueue_dequeue (candidate); | |
1099 | /* Update stat field in vertex. */ | |
1100 | *(v->stat) = LSA_SPF_IN_SPFTREE; | |
eb3da6df | 1101 | |
718e3744 | 1102 | ospf_vertex_add_parent (v); |
1103 | ||
718e3744 | 1104 | /* Note that when there is a choice of vertices closest to the |
1105 | root, network vertices must be chosen before router vertices | |
1106 | in order to necessarily find all equal-cost paths. */ | |
1107 | /* We don't do this at this moment, we should add the treatment | |
1108 | above codes. -- kunihiro. */ | |
1109 | ||
1110 | /* RFC2328 16.1. (4). */ | |
1111 | if (v->type == OSPF_VERTEX_ROUTER) | |
1112 | ospf_intra_add_router (new_rtrs, v, area); | |
0c0f9cd5 | 1113 | else |
718e3744 | 1114 | ospf_intra_add_transit (new_table, v, area); |
1115 | ||
1116 | /* RFC2328 16.1. (5). */ | |
1117 | /* Iterate the algorithm by returning to Step 2. */ | |
630e4807 | 1118 | |
1119 | } /* end loop until no more candidate vertices */ | |
718e3744 | 1120 | |
1121 | if (IS_DEBUG_OSPF_EVENT) | |
1122 | { | |
1123 | ospf_spf_dump (area->spf, 0); | |
1124 | ospf_route_table_dump (new_table); | |
1125 | } | |
1126 | ||
1127 | /* Second stage of SPF calculation procedure's */ | |
1128 | ospf_spf_process_stubs (area, area->spf, new_table); | |
1129 | ||
eb3da6df | 1130 | /* Free candidate queue. */ |
462f20d5 | 1131 | pqueue_delete (candidate); |
eb3da6df | 1132 | |
1133 | ospf_vertex_dump (__func__, area->spf, 0, 1); | |
1134 | /* Free nexthop information, canonical versions of which are attached | |
1135 | * the first level of router vertices attached to the root vertex, see | |
1136 | * ospf_nexthop_calculation. | |
1137 | */ | |
1138 | ospf_canonical_nexthops_free (area->spf); | |
1139 | ||
9c27ef9b PJ |
1140 | /* Free SPF vertices, but not the list. List has ospf_vertex_free |
1141 | * as deconstructor. | |
1142 | */ | |
1143 | list_delete_all_node (&vertex_list); | |
eb3da6df | 1144 | |
718e3744 | 1145 | /* Increment SPF Calculation Counter. */ |
1146 | area->spf_calculation++; | |
1147 | ||
2518efd1 | 1148 | quagga_gettime (QUAGGA_CLK_MONOTONIC, &area->ospf->ts_spf); |
718e3744 | 1149 | |
1150 | if (IS_DEBUG_OSPF_EVENT) | |
9c27ef9b PJ |
1151 | zlog_debug ("ospf_spf_calculate: Stop. %ld vertices", |
1152 | mtype_stats_alloc(MTYPE_OSPF_VERTEX)); | |
718e3744 | 1153 | } |
1154 | \f | |
1155 | /* Timer for SPF calculation. */ | |
4dadc291 | 1156 | static int |
68980084 | 1157 | ospf_spf_calculate_timer (struct thread *thread) |
718e3744 | 1158 | { |
68980084 | 1159 | struct ospf *ospf = THREAD_ARG (thread); |
718e3744 | 1160 | struct route_table *new_table, *new_rtrs; |
1eb8ef25 | 1161 | struct ospf_area *area; |
1162 | struct listnode *node, *nnode; | |
718e3744 | 1163 | |
1164 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1165 | zlog_debug ("SPF: Timer (SPF calculation expire)"); |
0c0f9cd5 | 1166 | |
718e3744 | 1167 | ospf->t_spf_calc = NULL; |
1168 | ||
1169 | /* Allocate new table tree. */ | |
1170 | new_table = route_table_init (); | |
0c0f9cd5 | 1171 | new_rtrs = route_table_init (); |
718e3744 | 1172 | |
68980084 | 1173 | ospf_vl_unapprove (ospf); |
718e3744 | 1174 | |
1175 | /* Calculate SPF for each area. */ | |
1eb8ef25 | 1176 | for (ALL_LIST_ELEMENTS (ospf->areas, node, nnode, area)) |
9c27ef9b PJ |
1177 | { |
1178 | /* Do backbone last, so as to first discover intra-area paths | |
1179 | * for any back-bone virtual-links | |
1180 | */ | |
1181 | if (ospf->backbone && ospf->backbone == area) | |
1182 | continue; | |
1183 | ||
1184 | ospf_spf_calculate (area, new_table, new_rtrs); | |
1185 | } | |
1186 | ||
1187 | /* SPF for backbone, if required */ | |
1188 | if (ospf->backbone) | |
1189 | ospf_spf_calculate (ospf->backbone, new_table, new_rtrs); | |
1190 | ||
68980084 | 1191 | ospf_vl_shut_unapproved (ospf); |
718e3744 | 1192 | |
68980084 | 1193 | ospf_ia_routing (ospf, new_table, new_rtrs); |
718e3744 | 1194 | |
1195 | ospf_prune_unreachable_networks (new_table); | |
1196 | ospf_prune_unreachable_routers (new_rtrs); | |
1197 | ||
1198 | /* AS-external-LSA calculation should not be performed here. */ | |
1199 | ||
1200 | /* If new Router Route is installed, | |
1201 | then schedule re-calculate External routes. */ | |
1202 | if (1) | |
68980084 | 1203 | ospf_ase_calculate_schedule (ospf); |
718e3744 | 1204 | |
68980084 | 1205 | ospf_ase_calculate_timer_add (ospf); |
718e3744 | 1206 | |
1207 | /* Update routing table. */ | |
68980084 | 1208 | ospf_route_install (ospf, new_table); |
718e3744 | 1209 | |
1210 | /* Update ABR/ASBR routing table */ | |
68980084 | 1211 | if (ospf->old_rtrs) |
718e3744 | 1212 | { |
1213 | /* old_rtrs's node holds linked list of ospf_route. --kunihiro. */ | |
68980084 | 1214 | /* ospf_route_delete (ospf->old_rtrs); */ |
1215 | ospf_rtrs_free (ospf->old_rtrs); | |
718e3744 | 1216 | } |
1217 | ||
68980084 | 1218 | ospf->old_rtrs = ospf->new_rtrs; |
1219 | ospf->new_rtrs = new_rtrs; | |
718e3744 | 1220 | |
0c0f9cd5 | 1221 | if (IS_OSPF_ABR (ospf)) |
68980084 | 1222 | ospf_abr_task (ospf); |
718e3744 | 1223 | |
1224 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1225 | zlog_debug ("SPF: calculation complete"); |
718e3744 | 1226 | |
1227 | return 0; | |
1228 | } | |
1229 | ||
1230 | /* Add schedule for SPF calculation. To avoid frequenst SPF calc, we | |
1231 | set timer for SPF calc. */ | |
1232 | void | |
68980084 | 1233 | ospf_spf_calculate_schedule (struct ospf *ospf) |
718e3744 | 1234 | { |
d24f6e2a | 1235 | unsigned long delay, elapsed, ht; |
1236 | struct timeval result; | |
718e3744 | 1237 | |
1238 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1239 | zlog_debug ("SPF: calculation timer scheduled"); |
718e3744 | 1240 | |
1241 | /* OSPF instance does not exist. */ | |
68980084 | 1242 | if (ospf == NULL) |
718e3744 | 1243 | return; |
d24f6e2a | 1244 | |
718e3744 | 1245 | /* SPF calculation timer is already scheduled. */ |
68980084 | 1246 | if (ospf->t_spf_calc) |
718e3744 | 1247 | { |
1248 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1249 | zlog_debug ("SPF: calculation timer is already scheduled: %p", |
0c0f9cd5 | 1250 | ospf->t_spf_calc); |
718e3744 | 1251 | return; |
1252 | } | |
d24f6e2a | 1253 | |
1254 | /* XXX Monotic timers: we only care about relative time here. */ | |
2518efd1 | 1255 | result = tv_sub (recent_relative_time (), ospf->ts_spf); |
d24f6e2a | 1256 | |
1257 | elapsed = (result.tv_sec * 1000) + (result.tv_usec / 1000); | |
1258 | ht = ospf->spf_holdtime * ospf->spf_hold_multiplier; | |
1259 | ||
1260 | if (ht > ospf->spf_max_holdtime) | |
1261 | ht = ospf->spf_max_holdtime; | |
1262 | ||
718e3744 | 1263 | /* Get SPF calculation delay time. */ |
d24f6e2a | 1264 | if (elapsed < ht) |
718e3744 | 1265 | { |
d24f6e2a | 1266 | /* Got an event within the hold time of last SPF. We need to |
1267 | * increase the hold_multiplier, if it's not already at/past | |
1268 | * maximum value, and wasn't already increased.. | |
1269 | */ | |
1270 | if (ht < ospf->spf_max_holdtime) | |
1271 | ospf->spf_hold_multiplier++; | |
1272 | ||
1273 | /* always honour the SPF initial delay */ | |
1274 | if ( (ht - elapsed) < ospf->spf_delay) | |
0c0f9cd5 | 1275 | delay = ospf->spf_delay; |
718e3744 | 1276 | else |
d24f6e2a | 1277 | delay = ht - elapsed; |
718e3744 | 1278 | } |
1279 | else | |
d24f6e2a | 1280 | { |
1281 | /* Event is past required hold-time of last SPF */ | |
1282 | delay = ospf->spf_delay; | |
1283 | ospf->spf_hold_multiplier = 1; | |
1284 | } | |
1285 | ||
718e3744 | 1286 | if (IS_DEBUG_OSPF_EVENT) |
d24f6e2a | 1287 | zlog_debug ("SPF: calculation timer delay = %ld", delay); |
1288 | ||
68980084 | 1289 | ospf->t_spf_calc = |
d24f6e2a | 1290 | thread_add_timer_msec (master, ospf_spf_calculate_timer, ospf, delay); |
718e3744 | 1291 | } |