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718e3744 | 1 | /* OSPF SPF calculation. |
896014f4 DL |
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 along | |
17 | * with this program; see the file COPYING; if not, write to the Free Software | |
18 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
19 | */ | |
718e3744 | 20 | |
21 | #include <zebra.h> | |
22 | ||
cbf3e3eb | 23 | #include "monotime.h" |
718e3744 | 24 | #include "thread.h" |
25 | #include "memory.h" | |
26 | #include "hash.h" | |
27 | #include "linklist.h" | |
28 | #include "prefix.h" | |
29 | #include "if.h" | |
30 | #include "table.h" | |
31 | #include "log.h" | |
d62a17ae | 32 | #include "sockunion.h" /* for inet_ntop () */ |
462f20d5 | 33 | #include "pqueue.h" |
718e3744 | 34 | |
35 | #include "ospfd/ospfd.h" | |
36 | #include "ospfd/ospf_interface.h" | |
37 | #include "ospfd/ospf_ism.h" | |
38 | #include "ospfd/ospf_asbr.h" | |
39 | #include "ospfd/ospf_lsa.h" | |
40 | #include "ospfd/ospf_lsdb.h" | |
41 | #include "ospfd/ospf_neighbor.h" | |
42 | #include "ospfd/ospf_nsm.h" | |
43 | #include "ospfd/ospf_spf.h" | |
44 | #include "ospfd/ospf_route.h" | |
45 | #include "ospfd/ospf_ia.h" | |
46 | #include "ospfd/ospf_ase.h" | |
47 | #include "ospfd/ospf_abr.h" | |
48 | #include "ospfd/ospf_dump.h" | |
cf9b9f77 | 49 | #include "ospfd/ospf_sr.h" |
718e3744 | 50 | |
cf744958 DS |
51 | /* Variables to ensure a SPF scheduled log message is printed only once */ |
52 | ||
53 | static unsigned int spf_reason_flags = 0; | |
54 | ||
d62a17ae | 55 | static void ospf_clear_spf_reason_flags(void) |
cf744958 | 56 | { |
d62a17ae | 57 | spf_reason_flags = 0; |
cf744958 DS |
58 | } |
59 | ||
d62a17ae | 60 | static void ospf_spf_set_reason(ospf_spf_reason_t reason) |
cf744958 | 61 | { |
d62a17ae | 62 | spf_reason_flags |= 1 << reason; |
cf744958 DS |
63 | } |
64 | ||
d62a17ae | 65 | static void ospf_vertex_free(void *); |
9c27ef9b PJ |
66 | /* List of allocated vertices, to simplify cleanup of SPF. |
67 | * Not thread-safe obviously. If it ever needs to be, it'd have to be | |
68 | * dynamically allocated at begin of ospf_spf_calculate | |
69 | */ | |
d62a17ae | 70 | static struct list vertex_list = {.del = ospf_vertex_free}; |
6b0655a2 | 71 | |
462f20d5 | 72 | /* Heap related functions, for the managment of the candidates, to |
73 | * be used with pqueue. */ | |
d62a17ae | 74 | static int cmp(void *node1, void *node2) |
462f20d5 | 75 | { |
d62a17ae | 76 | struct vertex *v1 = (struct vertex *)node1; |
77 | struct vertex *v2 = (struct vertex *)node2; | |
78 | if (v1 != NULL && v2 != NULL) { | |
79 | /* network vertices must be chosen before router vertices of | |
80 | * same | |
81 | * cost in order to find all shortest paths | |
82 | */ | |
83 | if (((v1->distance - v2->distance) == 0) | |
84 | && (v1->type != v2->type)) { | |
85 | switch (v1->type) { | |
86 | case OSPF_VERTEX_NETWORK: | |
87 | return -1; | |
88 | case OSPF_VERTEX_ROUTER: | |
89 | return 1; | |
90 | } | |
91 | } else | |
92 | return (v1->distance - v2->distance); | |
93 | } | |
94 | return 0; | |
462f20d5 | 95 | } |
96 | ||
d62a17ae | 97 | static void update_stat(void *node, int position) |
462f20d5 | 98 | { |
d62a17ae | 99 | struct vertex *v = node; |
eb3da6df | 100 | |
d62a17ae | 101 | /* Set the status of the vertex, when its position changes. */ |
102 | *(v->stat) = position; | |
462f20d5 | 103 | } |
6b0655a2 | 104 | |
d62a17ae | 105 | static struct vertex_nexthop *vertex_nexthop_new(void) |
718e3744 | 106 | { |
d62a17ae | 107 | return XCALLOC(MTYPE_OSPF_NEXTHOP, sizeof(struct vertex_nexthop)); |
718e3744 | 108 | } |
109 | ||
d62a17ae | 110 | static void vertex_nexthop_free(struct vertex_nexthop *nh) |
718e3744 | 111 | { |
d62a17ae | 112 | XFREE(MTYPE_OSPF_NEXTHOP, nh); |
718e3744 | 113 | } |
114 | ||
eb3da6df | 115 | /* Free the canonical nexthop objects for an area, ie the nexthop objects |
9c27ef9b PJ |
116 | * attached to the first-hop router vertices, and any intervening network |
117 | * vertices. | |
eb3da6df | 118 | */ |
d62a17ae | 119 | static void ospf_canonical_nexthops_free(struct vertex *root) |
718e3744 | 120 | { |
d62a17ae | 121 | struct listnode *node, *nnode; |
122 | struct vertex *child; | |
123 | ||
124 | for (ALL_LIST_ELEMENTS(root->children, node, nnode, child)) { | |
125 | struct listnode *n2, *nn2; | |
126 | struct vertex_parent *vp; | |
127 | ||
128 | /* router vertices through an attached network each | |
129 | * have a distinct (canonical / not inherited) nexthop | |
130 | * which must be freed. | |
131 | * | |
132 | * A network vertex can only have router vertices as its | |
133 | * children, so only one level of recursion is possible. | |
134 | */ | |
135 | if (child->type == OSPF_VERTEX_NETWORK) | |
136 | ospf_canonical_nexthops_free(child); | |
137 | ||
138 | /* Free child nexthops pointing back to this root vertex */ | |
139 | for (ALL_LIST_ELEMENTS(child->parents, n2, nn2, vp)) | |
cd4af525 | 140 | if (vp->parent == root && vp->nexthop) { |
d62a17ae | 141 | vertex_nexthop_free(vp->nexthop); |
cd4af525 CS |
142 | vp->nexthop = NULL; |
143 | } | |
d62a17ae | 144 | } |
145 | } | |
6b0655a2 | 146 | |
9c27ef9b PJ |
147 | /* TODO: Parent list should be excised, in favour of maintaining only |
148 | * vertex_nexthop, with refcounts. | |
149 | */ | |
d62a17ae | 150 | static struct vertex_parent *vertex_parent_new(struct vertex *v, int backlink, |
151 | struct vertex_nexthop *hop) | |
eb3da6df | 152 | { |
d62a17ae | 153 | struct vertex_parent *new; |
154 | ||
155 | new = XMALLOC(MTYPE_OSPF_VERTEX_PARENT, sizeof(struct vertex_parent)); | |
156 | ||
157 | if (new == NULL) | |
158 | return NULL; | |
159 | ||
160 | new->parent = v; | |
161 | new->backlink = backlink; | |
162 | new->nexthop = hop; | |
163 | return new; | |
718e3744 | 164 | } |
0c0f9cd5 | 165 | |
d62a17ae | 166 | static void vertex_parent_free(void *p) |
eb3da6df | 167 | { |
d62a17ae | 168 | XFREE(MTYPE_OSPF_VERTEX_PARENT, p); |
eb3da6df | 169 | } |
6b0655a2 | 170 | |
d62a17ae | 171 | static struct vertex *ospf_vertex_new(struct ospf_lsa *lsa) |
718e3744 | 172 | { |
d62a17ae | 173 | struct vertex *new; |
174 | ||
175 | new = XCALLOC(MTYPE_OSPF_VERTEX, sizeof(struct vertex)); | |
176 | ||
177 | new->flags = 0; | |
178 | new->stat = &(lsa->stat); | |
179 | new->type = lsa->data->type; | |
180 | new->id = lsa->data->id; | |
181 | new->lsa = lsa->data; | |
182 | new->children = list_new(); | |
183 | new->parents = list_new(); | |
184 | new->parents->del = vertex_parent_free; | |
185 | ||
186 | listnode_add(&vertex_list, new); | |
187 | ||
188 | if (IS_DEBUG_OSPF_EVENT) | |
189 | zlog_debug("%s: Created %s vertex %s", __func__, | |
190 | new->type == OSPF_VERTEX_ROUTER ? "Router" | |
191 | : "Network", | |
192 | inet_ntoa(new->lsa->id)); | |
193 | return new; | |
718e3744 | 194 | } |
195 | ||
d62a17ae | 196 | static void ospf_vertex_free(void *data) |
718e3744 | 197 | { |
d62a17ae | 198 | struct vertex *v = data; |
199 | ||
200 | if (IS_DEBUG_OSPF_EVENT) | |
201 | zlog_debug("%s: Free %s vertex %s", __func__, | |
202 | v->type == OSPF_VERTEX_ROUTER ? "Router" : "Network", | |
203 | inet_ntoa(v->lsa->id)); | |
204 | ||
205 | /* There should be no parents potentially holding references to this | |
206 | * vertex | |
207 | * Children however may still be there, but presumably referenced by | |
208 | * other | |
209 | * vertices | |
210 | */ | |
211 | // assert (listcount (v->parents) == 0); | |
212 | ||
213 | if (v->children) | |
affe9e99 | 214 | list_delete_and_null(&v->children); |
d62a17ae | 215 | |
216 | if (v->parents) | |
affe9e99 | 217 | list_delete_and_null(&v->parents); |
d62a17ae | 218 | |
219 | v->lsa = NULL; | |
220 | ||
221 | XFREE(MTYPE_OSPF_VERTEX, v); | |
718e3744 | 222 | } |
223 | ||
d62a17ae | 224 | static void ospf_vertex_dump(const char *msg, struct vertex *v, |
225 | int print_parents, int print_children) | |
630e4807 | 226 | { |
d62a17ae | 227 | if (!IS_DEBUG_OSPF_EVENT) |
228 | return; | |
229 | ||
230 | zlog_debug("%s %s vertex %s distance %u flags %u", msg, | |
231 | v->type == OSPF_VERTEX_ROUTER ? "Router" : "Network", | |
232 | inet_ntoa(v->lsa->id), v->distance, (unsigned int)v->flags); | |
233 | ||
234 | if (print_parents) { | |
235 | struct listnode *node; | |
236 | struct vertex_parent *vp; | |
237 | ||
238 | for (ALL_LIST_ELEMENTS_RO(v->parents, node, vp)) { | |
239 | char buf1[BUFSIZ]; | |
240 | ||
241 | if (vp) { | |
242 | zlog_debug( | |
243 | "parent %s backlink %d nexthop %s interface %s", | |
244 | inet_ntoa(vp->parent->lsa->id), | |
245 | vp->backlink, | |
246 | inet_ntop(AF_INET, &vp->nexthop->router, | |
247 | buf1, BUFSIZ), | |
248 | vp->nexthop->oi | |
249 | ? IF_NAME(vp->nexthop->oi) | |
250 | : "NULL"); | |
251 | } | |
252 | } | |
253 | } | |
254 | ||
255 | if (print_children) { | |
256 | struct listnode *cnode; | |
257 | struct vertex *cv; | |
258 | ||
259 | for (ALL_LIST_ELEMENTS_RO(v->children, cnode, cv)) | |
260 | ospf_vertex_dump(" child:", cv, 0, 0); | |
630e4807 | 261 | } |
630e4807 | 262 | } |
263 | ||
264 | ||
265 | /* Add a vertex to the list of children in each of its parents. */ | |
d62a17ae | 266 | static void ospf_vertex_add_parent(struct vertex *v) |
718e3744 | 267 | { |
d62a17ae | 268 | struct vertex_parent *vp; |
269 | struct listnode *node; | |
270 | ||
271 | assert(v && v->parents); | |
272 | ||
273 | for (ALL_LIST_ELEMENTS_RO(v->parents, node, vp)) { | |
274 | assert(vp->parent && vp->parent->children); | |
275 | ||
276 | /* No need to add two links from the same parent. */ | |
277 | if (listnode_lookup(vp->parent->children, v) == NULL) | |
278 | listnode_add(vp->parent->children, v); | |
279 | } | |
718e3744 | 280 | } |
6b0655a2 | 281 | |
d62a17ae | 282 | static void ospf_spf_init(struct ospf_area *area) |
718e3744 | 283 | { |
d62a17ae | 284 | struct vertex *v; |
285 | ||
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; | |
718e3744 | 294 | } |
295 | ||
d355bfa7 | 296 | /* return index of link back to V from W, or -1 if no link found */ |
d62a17ae | 297 | static int ospf_lsa_has_link(struct lsa_header *w, struct lsa_header *v) |
718e3744 | 298 | { |
d62a17ae | 299 | unsigned int i, length; |
300 | struct router_lsa *rl; | |
301 | struct network_lsa *nl; | |
302 | ||
303 | /* In case of W is Network LSA. */ | |
304 | if (w->type == OSPF_NETWORK_LSA) { | |
305 | if (v->type == OSPF_NETWORK_LSA) | |
306 | return -1; | |
307 | ||
308 | nl = (struct network_lsa *)w; | |
309 | length = (ntohs(w->length) - OSPF_LSA_HEADER_SIZE - 4) / 4; | |
310 | ||
311 | for (i = 0; i < length; i++) | |
312 | if (IPV4_ADDR_SAME(&nl->routers[i], &v->id)) | |
313 | return i; | |
314 | return -1; | |
315 | } | |
316 | ||
317 | /* In case of W is Router LSA. */ | |
318 | if (w->type == OSPF_ROUTER_LSA) { | |
319 | rl = (struct router_lsa *)w; | |
320 | ||
321 | length = ntohs(w->length); | |
322 | ||
323 | for (i = 0; i < ntohs(rl->links) | |
324 | && length >= sizeof(struct router_lsa); | |
325 | i++, length -= 12) { | |
326 | switch (rl->link[i].type) { | |
327 | case LSA_LINK_TYPE_POINTOPOINT: | |
328 | case LSA_LINK_TYPE_VIRTUALLINK: | |
329 | /* Router LSA ID. */ | |
330 | if (v->type == OSPF_ROUTER_LSA | |
331 | && IPV4_ADDR_SAME(&rl->link[i].link_id, | |
332 | &v->id)) { | |
333 | return i; | |
334 | } | |
335 | break; | |
336 | case LSA_LINK_TYPE_TRANSIT: | |
337 | /* Network LSA ID. */ | |
338 | if (v->type == OSPF_NETWORK_LSA | |
339 | && IPV4_ADDR_SAME(&rl->link[i].link_id, | |
340 | &v->id)) { | |
341 | return i; | |
342 | } | |
343 | break; | |
344 | case LSA_LINK_TYPE_STUB: | |
345 | /* Stub can't lead anywhere, carry on */ | |
346 | continue; | |
347 | default: | |
348 | break; | |
349 | } | |
350 | } | |
351 | } | |
352 | return -1; | |
718e3744 | 353 | } |
354 | ||
630e4807 | 355 | /* Find the next link after prev_link from v to w. If prev_link is |
356 | * NULL, return the first link from v to w. Ignore stub and virtual links; | |
357 | * these link types will never be returned. | |
358 | */ | |
4dadc291 | 359 | static struct router_lsa_link * |
d62a17ae | 360 | ospf_get_next_link(struct vertex *v, struct vertex *w, |
361 | struct router_lsa_link *prev_link) | |
718e3744 | 362 | { |
d7c0a89a QY |
363 | uint8_t *p; |
364 | uint8_t *lim; | |
365 | uint8_t lsa_type = LSA_LINK_TYPE_TRANSIT; | |
d62a17ae | 366 | struct router_lsa_link *l; |
367 | ||
368 | if (w->type == OSPF_VERTEX_ROUTER) | |
369 | lsa_type = LSA_LINK_TYPE_POINTOPOINT; | |
370 | ||
371 | if (prev_link == NULL) | |
d7c0a89a | 372 | p = ((uint8_t *)v->lsa) + OSPF_LSA_HEADER_SIZE + 4; |
d62a17ae | 373 | else { |
d7c0a89a | 374 | p = (uint8_t *)prev_link; |
d62a17ae | 375 | p += (OSPF_ROUTER_LSA_LINK_SIZE |
376 | + (prev_link->m[0].tos_count * OSPF_ROUTER_LSA_TOS_SIZE)); | |
377 | } | |
0c0f9cd5 | 378 | |
d7c0a89a | 379 | lim = ((uint8_t *)v->lsa) + ntohs(v->lsa->length); |
718e3744 | 380 | |
d62a17ae | 381 | while (p < lim) { |
382 | l = (struct router_lsa_link *)p; | |
718e3744 | 383 | |
d62a17ae | 384 | p += (OSPF_ROUTER_LSA_LINK_SIZE |
385 | + (l->m[0].tos_count * OSPF_ROUTER_LSA_TOS_SIZE)); | |
718e3744 | 386 | |
d62a17ae | 387 | if (l->m[0].type != lsa_type) |
388 | continue; | |
718e3744 | 389 | |
d62a17ae | 390 | if (IPV4_ADDR_SAME(&l->link_id, &w->id)) |
391 | return l; | |
392 | } | |
718e3744 | 393 | |
d62a17ae | 394 | return NULL; |
718e3744 | 395 | } |
396 | ||
d62a17ae | 397 | static void ospf_spf_flush_parents(struct vertex *w) |
bc20c1a4 | 398 | { |
d62a17ae | 399 | struct vertex_parent *vp; |
400 | struct listnode *ln, *nn; | |
401 | ||
402 | /* delete the existing nexthops */ | |
403 | for (ALL_LIST_ELEMENTS(w->parents, ln, nn, vp)) { | |
404 | list_delete_node(w->parents, ln); | |
405 | vertex_parent_free(vp); | |
406 | } | |
bc20c1a4 PJ |
407 | } |
408 | ||
d62a17ae | 409 | /* |
75ee0b8e | 410 | * Consider supplied next-hop for inclusion to the supplied list of |
d62a17ae | 411 | * equal-cost next-hops, adjust list as neccessary. |
bf9392c6 | 412 | */ |
d62a17ae | 413 | static void ospf_spf_add_parent(struct vertex *v, struct vertex *w, |
414 | struct vertex_nexthop *newhop, | |
415 | unsigned int distance) | |
bf9392c6 | 416 | { |
d62a17ae | 417 | struct vertex_parent *vp, *wp; |
418 | struct listnode *node; | |
419 | ||
420 | /* we must have a newhop, and a distance */ | |
421 | assert(v && w && newhop); | |
422 | assert(distance); | |
423 | ||
424 | /* IFF w has already been assigned a distance, then we shouldn't get | |
425 | * here | |
426 | * unless callers have determined V(l)->W is shortest / equal-shortest | |
427 | * path (0 is a special case distance (no distance yet assigned)). | |
428 | */ | |
429 | if (w->distance) | |
430 | assert(distance <= w->distance); | |
431 | else | |
432 | w->distance = distance; | |
433 | ||
434 | if (IS_DEBUG_OSPF_EVENT) { | |
435 | char buf[2][INET_ADDRSTRLEN]; | |
436 | zlog_debug( | |
437 | "%s: Adding %s as parent of %s", __func__, | |
438 | inet_ntop(AF_INET, &v->lsa->id, buf[0], sizeof(buf[0])), | |
439 | inet_ntop(AF_INET, &w->lsa->id, buf[1], | |
440 | sizeof(buf[1]))); | |
441 | } | |
442 | ||
443 | /* Adding parent for a new, better path: flush existing parents from W. | |
444 | */ | |
445 | if (distance < w->distance) { | |
446 | if (IS_DEBUG_OSPF_EVENT) | |
447 | zlog_debug( | |
448 | "%s: distance %d better than %d, flushing existing parents", | |
449 | __func__, distance, w->distance); | |
450 | ospf_spf_flush_parents(w); | |
451 | w->distance = distance; | |
452 | } | |
453 | ||
454 | /* new parent is <= existing parents, add it to parent list (if nexthop | |
455 | * not on parent list) | |
456 | */ | |
457 | for (ALL_LIST_ELEMENTS_RO(w->parents, node, wp)) { | |
458 | if (memcmp(newhop, wp->nexthop, sizeof(*newhop)) == 0) { | |
459 | if (IS_DEBUG_OSPF_EVENT) | |
460 | zlog_debug( | |
461 | "%s: ... nexthop already on parent list, skipping add", | |
462 | __func__); | |
463 | return; | |
464 | } | |
465 | } | |
7b92589c | 466 | |
d62a17ae | 467 | vp = vertex_parent_new(v, ospf_lsa_has_link(w->lsa, v->lsa), newhop); |
468 | listnode_add(w->parents, vp); | |
0c0f9cd5 | 469 | |
d62a17ae | 470 | return; |
eb3da6df | 471 | } |
472 | ||
630e4807 | 473 | /* 16.1.1. Calculate nexthop from root through V (parent) to |
bd34fb34 | 474 | * vertex W (destination), with given distance from root->W. |
eb3da6df | 475 | * |
476 | * The link must be supplied if V is the root vertex. In all other cases | |
477 | * it may be NULL. | |
bd34fb34 PJ |
478 | * |
479 | * Note that this function may fail, hence the state of the destination | |
480 | * vertex, W, should /not/ be modified in a dependent manner until | |
481 | * this function returns. This function will update the W vertex with the | |
482 | * provided distance as appropriate. | |
630e4807 | 483 | */ |
d62a17ae | 484 | static unsigned int ospf_nexthop_calculation(struct ospf_area *area, |
485 | struct vertex *v, struct vertex *w, | |
486 | struct router_lsa_link *l, | |
487 | unsigned int distance, int lsa_pos) | |
718e3744 | 488 | { |
d62a17ae | 489 | struct listnode *node, *nnode; |
490 | struct vertex_nexthop *nh; | |
491 | struct vertex_parent *vp; | |
492 | struct ospf_interface *oi = NULL; | |
493 | unsigned int added = 0; | |
494 | char buf1[BUFSIZ]; | |
495 | char buf2[BUFSIZ]; | |
496 | ||
497 | if (IS_DEBUG_OSPF_EVENT) { | |
498 | zlog_debug("ospf_nexthop_calculation(): Start"); | |
499 | ospf_vertex_dump("V (parent):", v, 1, 1); | |
500 | ospf_vertex_dump("W (dest) :", w, 1, 1); | |
501 | zlog_debug("V->W distance: %d", distance); | |
c81ee5c9 JT |
502 | } |
503 | ||
d62a17ae | 504 | if (v == area->spf) { |
505 | /* 16.1.1 para 4. In the first case, the parent vertex (V) is | |
506 | the | |
507 | root (the calculating router itself). This means that the | |
508 | destination is either a directly connected network or | |
509 | directly | |
510 | connected router. The outgoing interface in this case is | |
511 | simply | |
512 | the OSPF interface connecting to the destination | |
513 | network/router. | |
514 | */ | |
515 | ||
516 | /* we *must* be supplied with the link data */ | |
517 | assert(l != NULL); | |
518 | oi = ospf_if_lookup_by_lsa_pos(area, lsa_pos); | |
519 | if (!oi) { | |
520 | zlog_debug( | |
521 | "%s: OI not found in LSA: lsa_pos:%d link_id:%s link_data:%s", | |
522 | __func__, lsa_pos, | |
523 | inet_ntop(AF_INET, &l->link_id, buf1, BUFSIZ), | |
524 | inet_ntop(AF_INET, &l->link_data, buf2, | |
525 | BUFSIZ)); | |
526 | return 0; | |
c81ee5c9 | 527 | } |
c81ee5c9 | 528 | |
d62a17ae | 529 | if (IS_DEBUG_OSPF_EVENT) { |
530 | zlog_debug( | |
531 | "%s: considering link:%s " | |
532 | "type:%d link_id:%s link_data:%s", | |
533 | __func__, oi->ifp->name, l->m[0].type, | |
534 | inet_ntop(AF_INET, &l->link_id, buf1, BUFSIZ), | |
535 | inet_ntop(AF_INET, &l->link_data, buf2, | |
536 | BUFSIZ)); | |
537 | } | |
c81ee5c9 | 538 | |
d62a17ae | 539 | if (w->type == OSPF_VERTEX_ROUTER) { |
540 | /* l is a link from v to w | |
541 | * l2 will be link from w to v | |
542 | */ | |
543 | struct router_lsa_link *l2 = NULL; | |
544 | ||
545 | if (l->m[0].type == LSA_LINK_TYPE_POINTOPOINT) { | |
546 | struct in_addr nexthop = {.s_addr = 0}; | |
547 | ||
548 | /* If the destination is a router which connects | |
549 | to | |
550 | the calculating router via a | |
551 | Point-to-MultiPoint | |
552 | network, the destination's next hop IP | |
553 | address(es) | |
554 | can be determined by examining the | |
555 | destination's | |
556 | router-LSA: each link pointing back to the | |
557 | calculating router and having a Link Data | |
558 | field | |
559 | belonging to the Point-to-MultiPoint network | |
560 | provides an IP address of the next hop | |
561 | router. | |
562 | ||
563 | At this point l is a link from V to W, and V | |
564 | is the | |
565 | root ("us"). If it is a point-to-multipoint | |
566 | interface, | |
567 | then look through the links in the opposite | |
568 | direction (W to V). | |
569 | If any of them have an address that lands | |
570 | within the | |
571 | subnet declared by the PtMP link, then that | |
572 | link | |
573 | is a constituent of the PtMP link, and its | |
574 | address is | |
575 | a nexthop address for V. | |
576 | */ | |
577 | if (oi->type == OSPF_IFTYPE_POINTOPOINT) { | |
578 | /* Having nexthop = 0 is tempting, but | |
579 | NOT acceptable. | |
580 | It breaks AS-External routes with a | |
581 | forwarding address, | |
582 | since | |
583 | ospf_ase_complete_direct_routes() | |
584 | will mistakenly | |
585 | assume we've reached the last hop and | |
586 | should place the | |
587 | forwarding address as nexthop. | |
588 | Also, users may configure | |
589 | multi-access links in p2p mode, | |
590 | so we need the IP to ARP the nexthop. | |
591 | */ | |
592 | struct ospf_neighbor *nbr_w; | |
593 | ||
594 | nbr_w = ospf_nbr_lookup_by_routerid( | |
595 | oi->nbrs, &l->link_id); | |
596 | if (nbr_w != NULL) { | |
597 | added = 1; | |
598 | nexthop = nbr_w->src; | |
599 | } | |
600 | } else if (oi->type | |
601 | == OSPF_IFTYPE_POINTOMULTIPOINT) { | |
602 | struct prefix_ipv4 la; | |
603 | ||
604 | la.family = AF_INET; | |
605 | la.prefixlen = oi->address->prefixlen; | |
606 | ||
607 | /* V links to W on PtMP interface | |
608 | - find the interface address on W */ | |
609 | while ((l2 = ospf_get_next_link(w, v, | |
610 | l2))) { | |
611 | la.prefix = l2->link_data; | |
612 | ||
613 | if (prefix_cmp((struct prefix | |
614 | *)&la, | |
615 | oi->address) | |
616 | != 0) | |
617 | continue; | |
618 | /* link_data is on our PtMP | |
619 | * network */ | |
620 | added = 1; | |
621 | nexthop = l2->link_data; | |
622 | break; | |
623 | } | |
624 | } | |
625 | ||
626 | if (added) { | |
627 | /* found all necessary info to build | |
628 | * nexthop */ | |
629 | nh = vertex_nexthop_new(); | |
630 | nh->oi = oi; | |
631 | nh->router = nexthop; | |
632 | ospf_spf_add_parent(v, w, nh, distance); | |
633 | return 1; | |
634 | } else | |
635 | zlog_info( | |
636 | "%s: could not determine nexthop for link %s", | |
637 | __func__, oi->ifp->name); | |
638 | } /* end point-to-point link from V to W */ | |
639 | else if (l->m[0].type == LSA_LINK_TYPE_VIRTUALLINK) { | |
640 | struct ospf_vl_data *vl_data; | |
641 | ||
642 | /* VLink implementation limitations: | |
643 | * a) vl_data can only reference one nexthop, so | |
644 | * no ECMP | |
645 | * to backbone through VLinks. Though | |
646 | * transit-area | |
647 | * summaries may be considered, and those can | |
648 | * be ECMP. | |
649 | * b) We can only use /one/ VLink, even if | |
650 | * multiple ones | |
651 | * exist this router through multiple | |
652 | * transit-areas. | |
653 | */ | |
654 | vl_data = ospf_vl_lookup(area->ospf, NULL, | |
655 | l->link_id); | |
656 | ||
657 | if (vl_data | |
658 | && CHECK_FLAG(vl_data->flags, | |
659 | OSPF_VL_FLAG_APPROVED)) { | |
660 | nh = vertex_nexthop_new(); | |
661 | nh->oi = vl_data->nexthop.oi; | |
662 | nh->router = vl_data->nexthop.router; | |
663 | ospf_spf_add_parent(v, w, nh, distance); | |
664 | return 1; | |
665 | } else | |
666 | zlog_info( | |
667 | "ospf_nexthop_calculation(): " | |
668 | "vl_data for VL link not found"); | |
669 | } /* end virtual-link from V to W */ | |
670 | return 0; | |
671 | } /* end W is a Router vertex */ | |
672 | else { | |
673 | assert(w->type == OSPF_VERTEX_NETWORK); | |
674 | ||
675 | nh = vertex_nexthop_new(); | |
676 | nh->oi = oi; | |
677 | nh->router.s_addr = 0; /* Nexthop not required */ | |
678 | ospf_spf_add_parent(v, w, nh, distance); | |
679 | return 1; | |
680 | } | |
681 | } /* end V is the root */ | |
682 | /* Check if W's parent is a network connected to root. */ | |
683 | else if (v->type == OSPF_VERTEX_NETWORK) { | |
684 | /* See if any of V's parents are the root. */ | |
685 | for (ALL_LIST_ELEMENTS(v->parents, node, nnode, vp)) { | |
686 | if (vp->parent == area->spf) /* connects to root? */ | |
687 | { | |
688 | /* 16.1.1 para 5. ...the parent vertex is a | |
689 | * network that | |
690 | * directly connects the calculating router to | |
691 | * the destination | |
692 | * router. The list of next hops is then | |
693 | * determined by | |
694 | * examining the destination's router-LSA... | |
695 | */ | |
696 | ||
697 | assert(w->type == OSPF_VERTEX_ROUTER); | |
698 | while ((l = ospf_get_next_link(w, v, l))) { | |
699 | /* ...For each link in the router-LSA | |
700 | * that points back to the | |
701 | * parent network, the link's Link Data | |
702 | * field provides the IP | |
703 | * address of a next hop router. The | |
704 | * outgoing interface to | |
705 | * use can then be derived from the next | |
706 | * hop IP address (or | |
707 | * it can be inherited from the parent | |
708 | * network). | |
709 | */ | |
710 | nh = vertex_nexthop_new(); | |
711 | nh->oi = vp->nexthop->oi; | |
712 | nh->router = l->link_data; | |
713 | added = 1; | |
714 | ospf_spf_add_parent(v, w, nh, distance); | |
715 | } | |
716 | /* Note lack of return is deliberate. See next | |
717 | * comment. */ | |
718 | } | |
c81ee5c9 | 719 | } |
d62a17ae | 720 | /* NB: This code is non-trivial. |
721 | * | |
722 | * E.g. it is not enough to know that V connects to the root. It | |
723 | * is | |
724 | * also important that the while above, looping through all | |
725 | * links from | |
726 | * W->V found at least one link, so that we know there is | |
727 | * bi-directional connectivity between V and W (which need not | |
728 | * be the | |
729 | * case, e.g. when OSPF has not yet converged fully). | |
730 | * Otherwise, if | |
731 | * we /always/ return here, without having checked that | |
732 | * root->V->-W | |
733 | * actually resulted in a valid nexthop being created, then we | |
734 | * we will | |
735 | * prevent SPF from finding/using higher cost paths. | |
736 | * | |
737 | * It is important, if root->V->W has not been added, that we | |
738 | * continue | |
739 | * through to the intervening-router nexthop code below. So as | |
740 | * to | |
741 | * ensure other paths to V may be used. This avoids unnecessary | |
742 | * blackholes while OSPF is convergening. | |
743 | * | |
744 | * I.e. we may have arrived at this function, examining V -> W, | |
745 | * via | |
746 | * workable paths other than root -> V, and it's important to | |
747 | * avoid | |
748 | * getting "confused" by non-working root->V->W path - it's | |
749 | * important | |
750 | * to *not* lose the working non-root paths, just because of a | |
751 | * non-viable root->V->W. | |
752 | * | |
753 | * See also bug #330 (required reading!), and: | |
754 | * | |
755 | * http://blogs.oracle.com/paulj/entry/the_difference_a_line_makes | |
756 | */ | |
757 | if (added) | |
758 | return added; | |
759 | } | |
c81ee5c9 | 760 | |
d62a17ae | 761 | /* 16.1.1 para 4. If there is at least one intervening router in the |
762 | * current shortest path between the destination and the root, the | |
763 | * destination simply inherits the set of next hops from the | |
764 | * parent. | |
765 | */ | |
766 | if (IS_DEBUG_OSPF_EVENT) | |
767 | zlog_debug("%s: Intervening routers, adding parent(s)", | |
768 | __func__); | |
769 | ||
770 | for (ALL_LIST_ELEMENTS(v->parents, node, nnode, vp)) { | |
771 | added = 1; | |
772 | ospf_spf_add_parent(v, w, vp->nexthop, distance); | |
773 | } | |
c81ee5c9 | 774 | |
d62a17ae | 775 | return added; |
718e3744 | 776 | } |
777 | ||
630e4807 | 778 | /* RFC2328 Section 16.1 (2). |
779 | * v is on the SPF tree. Examine the links in v's LSA. Update the list | |
780 | * of candidates with any vertices not already on the list. If a lower-cost | |
781 | * path is found to a vertex already on the candidate list, store the new cost. | |
782 | */ | |
b5a8894d | 783 | static void ospf_spf_next(struct vertex *v, struct ospf *ospf, |
996c9314 | 784 | struct ospf_area *area, struct pqueue *candidate) |
718e3744 | 785 | { |
d62a17ae | 786 | struct ospf_lsa *w_lsa = NULL; |
d7c0a89a QY |
787 | uint8_t *p; |
788 | uint8_t *lim; | |
d62a17ae | 789 | struct router_lsa_link *l = NULL; |
790 | struct in_addr *r; | |
791 | int type = 0, lsa_pos = -1, lsa_pos_next = 0; | |
792 | ||
793 | /* If this is a router-LSA, and bit V of the router-LSA (see Section | |
794 | A.4.2:RFC2328) is set, set Area A's TransitCapability to TRUE. */ | |
795 | if (v->type == OSPF_VERTEX_ROUTER) { | |
796 | if (IS_ROUTER_LSA_VIRTUAL((struct router_lsa *)v->lsa)) | |
797 | area->transit = OSPF_TRANSIT_TRUE; | |
798 | } | |
718e3744 | 799 | |
d62a17ae | 800 | if (IS_DEBUG_OSPF_EVENT) |
801 | zlog_debug("%s: Next vertex of %s vertex %s", __func__, | |
802 | v->type == OSPF_VERTEX_ROUTER ? "Router" : "Network", | |
803 | inet_ntoa(v->lsa->id)); | |
804 | ||
d7c0a89a QY |
805 | p = ((uint8_t *)v->lsa) + OSPF_LSA_HEADER_SIZE + 4; |
806 | lim = ((uint8_t *)v->lsa) + ntohs(v->lsa->length); | |
d62a17ae | 807 | |
808 | while (p < lim) { | |
809 | struct vertex *w; | |
810 | unsigned int distance; | |
811 | ||
812 | /* In case of V is Router-LSA. */ | |
813 | if (v->lsa->type == OSPF_ROUTER_LSA) { | |
814 | l = (struct router_lsa_link *)p; | |
815 | ||
816 | lsa_pos = lsa_pos_next; /* LSA link position */ | |
817 | lsa_pos_next++; | |
818 | p += (OSPF_ROUTER_LSA_LINK_SIZE | |
819 | + (l->m[0].tos_count * OSPF_ROUTER_LSA_TOS_SIZE)); | |
820 | ||
821 | /* (a) If this is a link to a stub network, examine the | |
822 | next | |
823 | link in V's LSA. Links to stub networks will be | |
824 | considered in the second stage of the shortest path | |
825 | calculation. */ | |
826 | if ((type = l->m[0].type) == LSA_LINK_TYPE_STUB) | |
827 | continue; | |
828 | ||
829 | /* (b) Otherwise, W is a transit vertex (router or | |
830 | transit | |
831 | network). Look up the vertex W's LSA (router-LSA or | |
832 | network-LSA) in Area A's link state database. */ | |
833 | switch (type) { | |
834 | case LSA_LINK_TYPE_POINTOPOINT: | |
835 | case LSA_LINK_TYPE_VIRTUALLINK: | |
836 | if (type == LSA_LINK_TYPE_VIRTUALLINK) { | |
837 | if (IS_DEBUG_OSPF_EVENT) | |
838 | zlog_debug( | |
839 | "looking up LSA through VL: %s", | |
840 | inet_ntoa(l->link_id)); | |
841 | } | |
842 | ||
b5a8894d CS |
843 | w_lsa = ospf_lsa_lookup(ospf, area, |
844 | OSPF_ROUTER_LSA, | |
d62a17ae | 845 | l->link_id, l->link_id); |
846 | if (w_lsa) { | |
847 | if (IS_DEBUG_OSPF_EVENT) | |
848 | zlog_debug( | |
849 | "found Router LSA %s", | |
850 | inet_ntoa(l->link_id)); | |
851 | } | |
852 | break; | |
853 | case LSA_LINK_TYPE_TRANSIT: | |
854 | if (IS_DEBUG_OSPF_EVENT) | |
855 | zlog_debug( | |
856 | "Looking up Network LSA, ID: %s", | |
857 | inet_ntoa(l->link_id)); | |
858 | w_lsa = ospf_lsa_lookup_by_id( | |
859 | area, OSPF_NETWORK_LSA, l->link_id); | |
860 | if (w_lsa) | |
861 | if (IS_DEBUG_OSPF_EVENT) | |
862 | zlog_debug("found the LSA"); | |
863 | break; | |
864 | default: | |
865 | zlog_warn("Invalid LSA link type %d", type); | |
866 | continue; | |
867 | } | |
868 | } else { | |
869 | /* In case of V is Network-LSA. */ | |
870 | r = (struct in_addr *)p; | |
871 | p += sizeof(struct in_addr); | |
872 | ||
873 | /* Lookup the vertex W's LSA. */ | |
874 | w_lsa = ospf_lsa_lookup_by_id(area, OSPF_ROUTER_LSA, | |
875 | *r); | |
876 | if (w_lsa) { | |
877 | if (IS_DEBUG_OSPF_EVENT) | |
878 | zlog_debug("found Router LSA %s", | |
879 | inet_ntoa(w_lsa->data->id)); | |
880 | } | |
881 | } | |
718e3744 | 882 | |
d62a17ae | 883 | /* (b cont.) If the LSA does not exist, or its LS age is equal |
884 | to MaxAge, or it does not have a link back to vertex V, | |
885 | examine the next link in V's LSA.[23] */ | |
886 | if (w_lsa == NULL) { | |
887 | if (IS_DEBUG_OSPF_EVENT) | |
888 | zlog_debug("No LSA found"); | |
889 | continue; | |
890 | } | |
718e3744 | 891 | |
d62a17ae | 892 | if (IS_LSA_MAXAGE(w_lsa)) { |
893 | if (IS_DEBUG_OSPF_EVENT) | |
894 | zlog_debug("LSA is MaxAge"); | |
895 | continue; | |
896 | } | |
718e3744 | 897 | |
d62a17ae | 898 | if (ospf_lsa_has_link(w_lsa->data, v->lsa) < 0) { |
899 | if (IS_DEBUG_OSPF_EVENT) | |
900 | zlog_debug("The LSA doesn't have a link back"); | |
901 | continue; | |
902 | } | |
718e3744 | 903 | |
d62a17ae | 904 | /* (c) If vertex W is already on the shortest-path tree, examine |
905 | the next link in the LSA. */ | |
906 | if (w_lsa->stat == LSA_SPF_IN_SPFTREE) { | |
907 | if (IS_DEBUG_OSPF_EVENT) | |
908 | zlog_debug("The LSA is already in SPF"); | |
909 | continue; | |
910 | } | |
718e3744 | 911 | |
d62a17ae | 912 | /* (d) Calculate the link state cost D of the resulting path |
913 | from the root to vertex W. D is equal to the sum of the link | |
914 | state cost of the (already calculated) shortest path to | |
915 | vertex V and the advertised cost of the link between vertices | |
916 | V and W. If D is: */ | |
917 | ||
918 | /* calculate link cost D. */ | |
919 | if (v->lsa->type == OSPF_ROUTER_LSA) | |
920 | distance = v->distance + ntohs(l->m[0].metric); | |
921 | else /* v is not a Router-LSA */ | |
922 | distance = v->distance; | |
923 | ||
924 | /* Is there already vertex W in candidate list? */ | |
925 | if (w_lsa->stat == LSA_SPF_NOT_EXPLORED) { | |
926 | /* prepare vertex W. */ | |
927 | w = ospf_vertex_new(w_lsa); | |
928 | ||
929 | /* Calculate nexthop to W. */ | |
930 | if (ospf_nexthop_calculation(area, v, w, l, distance, | |
931 | lsa_pos)) | |
932 | pqueue_enqueue(w, candidate); | |
933 | else if (IS_DEBUG_OSPF_EVENT) | |
934 | zlog_debug("Nexthop Calc failed"); | |
935 | } else if (w_lsa->stat >= 0) { | |
936 | /* Get the vertex from candidates. */ | |
937 | w = candidate->array[w_lsa->stat]; | |
938 | ||
939 | /* if D is greater than. */ | |
940 | if (w->distance < distance) { | |
941 | continue; | |
942 | } | |
943 | /* equal to. */ | |
944 | else if (w->distance == distance) { | |
945 | /* Found an equal-cost path to W. | |
946 | * Calculate nexthop of to W from V. */ | |
947 | ospf_nexthop_calculation(area, v, w, l, | |
948 | distance, lsa_pos); | |
949 | } | |
950 | /* less than. */ | |
951 | else { | |
952 | /* Found a lower-cost path to W. | |
953 | * nexthop_calculation is conditional, if it | |
954 | * finds | |
955 | * valid nexthop it will call spf_add_parents, | |
956 | * which | |
957 | * will flush the old parents | |
958 | */ | |
959 | if (ospf_nexthop_calculation(area, v, w, l, | |
960 | distance, lsa_pos)) | |
961 | /* Decrease the key of the node in the | |
962 | * heap. | |
963 | * trickle-sort it up towards root, just | |
964 | * in case this | |
965 | * node should now be the new root due | |
966 | * the cost change. | |
967 | * (next pqueu_{de,en}queue will fully | |
968 | * re-heap the queue). | |
969 | */ | |
970 | trickle_up(w_lsa->stat, candidate); | |
971 | } | |
972 | } /* end W is already on the candidate list */ | |
973 | } /* end loop over the links in V's LSA */ | |
974 | } | |
718e3744 | 975 | |
d62a17ae | 976 | static void ospf_spf_dump(struct vertex *v, int i) |
977 | { | |
978 | struct listnode *cnode; | |
979 | struct listnode *nnode; | |
980 | struct vertex_parent *parent; | |
981 | ||
982 | if (v->type == OSPF_VERTEX_ROUTER) { | |
983 | if (IS_DEBUG_OSPF_EVENT) | |
984 | zlog_debug("SPF Result: %d [R] %s", i, | |
985 | inet_ntoa(v->lsa->id)); | |
986 | } else { | |
987 | struct network_lsa *lsa = (struct network_lsa *)v->lsa; | |
988 | if (IS_DEBUG_OSPF_EVENT) | |
989 | zlog_debug("SPF Result: %d [N] %s/%d", i, | |
990 | inet_ntoa(v->lsa->id), | |
991 | ip_masklen(lsa->mask)); | |
462f20d5 | 992 | } |
718e3744 | 993 | |
d62a17ae | 994 | if (IS_DEBUG_OSPF_EVENT) |
995 | for (ALL_LIST_ELEMENTS_RO(v->parents, nnode, parent)) { | |
996 | zlog_debug(" nexthop %p %s %s", (void *)parent->nexthop, | |
997 | inet_ntoa(parent->nexthop->router), | |
998 | parent->nexthop->oi | |
999 | ? IF_NAME(parent->nexthop->oi) | |
1000 | : "NULL"); | |
1001 | } | |
718e3744 | 1002 | |
d62a17ae | 1003 | i++; |
718e3744 | 1004 | |
d62a17ae | 1005 | for (ALL_LIST_ELEMENTS_RO(v->children, cnode, v)) |
1006 | ospf_spf_dump(v, i); | |
718e3744 | 1007 | } |
1008 | ||
1009 | /* Second stage of SPF calculation. */ | |
d62a17ae | 1010 | static void ospf_spf_process_stubs(struct ospf_area *area, struct vertex *v, |
1011 | struct route_table *rt, int parent_is_root) | |
718e3744 | 1012 | { |
d62a17ae | 1013 | struct listnode *cnode, *cnnode; |
1014 | struct vertex *child; | |
1015 | ||
1016 | if (IS_DEBUG_OSPF_EVENT) | |
1017 | zlog_debug("ospf_process_stub():processing stubs for area %s", | |
1018 | inet_ntoa(area->area_id)); | |
1019 | if (v->type == OSPF_VERTEX_ROUTER) { | |
d7c0a89a QY |
1020 | uint8_t *p; |
1021 | uint8_t *lim; | |
d62a17ae | 1022 | struct router_lsa_link *l; |
1023 | struct router_lsa *rlsa; | |
1024 | int lsa_pos = 0; | |
1025 | ||
1026 | if (IS_DEBUG_OSPF_EVENT) | |
1027 | zlog_debug( | |
1028 | "ospf_process_stubs():processing router LSA, id: %s", | |
1029 | inet_ntoa(v->lsa->id)); | |
1030 | rlsa = (struct router_lsa *)v->lsa; | |
1031 | ||
1032 | ||
1033 | if (IS_DEBUG_OSPF_EVENT) | |
1034 | zlog_debug( | |
1035 | "ospf_process_stubs(): we have %d links to process", | |
1036 | ntohs(rlsa->links)); | |
d7c0a89a QY |
1037 | p = ((uint8_t *)v->lsa) + OSPF_LSA_HEADER_SIZE + 4; |
1038 | lim = ((uint8_t *)v->lsa) + ntohs(v->lsa->length); | |
d62a17ae | 1039 | |
1040 | while (p < lim) { | |
1041 | l = (struct router_lsa_link *)p; | |
1042 | ||
1043 | p += (OSPF_ROUTER_LSA_LINK_SIZE | |
1044 | + (l->m[0].tos_count * OSPF_ROUTER_LSA_TOS_SIZE)); | |
1045 | ||
1046 | if (l->m[0].type == LSA_LINK_TYPE_STUB) | |
1047 | ospf_intra_add_stub(rt, l, v, area, | |
1048 | parent_is_root, lsa_pos); | |
1049 | lsa_pos++; | |
1050 | } | |
1051 | } | |
718e3744 | 1052 | |
d62a17ae | 1053 | ospf_vertex_dump("ospf_process_stubs(): after examining links: ", v, 1, |
1054 | 1); | |
718e3744 | 1055 | |
d62a17ae | 1056 | for (ALL_LIST_ELEMENTS(v->children, cnode, cnnode, child)) { |
1057 | if (CHECK_FLAG(child->flags, OSPF_VERTEX_PROCESSED)) | |
1058 | continue; | |
718e3744 | 1059 | |
d62a17ae | 1060 | /* the first level of routers connected to the root |
1061 | * should have 'parent_is_root' set, including those | |
1062 | * connected via a network vertex. | |
1063 | */ | |
1064 | if (area->spf == v) | |
1065 | parent_is_root = 1; | |
1066 | else if (v->type == OSPF_VERTEX_ROUTER) | |
1067 | parent_is_root = 0; | |
1068 | ||
1069 | ospf_spf_process_stubs(area, child, rt, parent_is_root); | |
1070 | ||
1071 | SET_FLAG(child->flags, OSPF_VERTEX_PROCESSED); | |
1072 | } | |
718e3744 | 1073 | } |
1074 | ||
d62a17ae | 1075 | void ospf_rtrs_free(struct route_table *rtrs) |
718e3744 | 1076 | { |
d62a17ae | 1077 | struct route_node *rn; |
1078 | struct list *or_list; | |
1079 | struct ospf_route * or ; | |
1080 | struct listnode *node, *nnode; | |
718e3744 | 1081 | |
d62a17ae | 1082 | if (IS_DEBUG_OSPF_EVENT) |
1083 | zlog_debug("Route: Router Routing Table free"); | |
718e3744 | 1084 | |
d62a17ae | 1085 | for (rn = route_top(rtrs); rn; rn = route_next(rn)) |
1086 | if ((or_list = rn->info) != NULL) { | |
1087 | for (ALL_LIST_ELEMENTS(or_list, node, nnode, or)) | |
1088 | ospf_route_free(or); | |
718e3744 | 1089 | |
affe9e99 | 1090 | list_delete_and_null(&or_list); |
718e3744 | 1091 | |
d62a17ae | 1092 | /* Unlock the node. */ |
1093 | rn->info = NULL; | |
1094 | route_unlock_node(rn); | |
1095 | } | |
1096 | route_table_finish(rtrs); | |
718e3744 | 1097 | } |
1098 | ||
075e12f5 | 1099 | #if 0 |
4dadc291 | 1100 | static void |
718e3744 | 1101 | ospf_rtrs_print (struct route_table *rtrs) |
1102 | { | |
1103 | struct route_node *rn; | |
52dc7ee6 | 1104 | struct list *or_list; |
1105 | struct listnode *ln; | |
1106 | struct listnode *pnode; | |
718e3744 | 1107 | struct ospf_route *or; |
1108 | struct ospf_path *path; | |
1109 | char buf1[BUFSIZ]; | |
1110 | char buf2[BUFSIZ]; | |
1111 | ||
1112 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1113 | zlog_debug ("ospf_rtrs_print() start"); |
718e3744 | 1114 | |
1115 | for (rn = route_top (rtrs); rn; rn = route_next (rn)) | |
1116 | if ((or_list = rn->info) != NULL) | |
1eb8ef25 | 1117 | for (ALL_LIST_ELEMENTS_RO (or_list, ln, or)) |
718e3744 | 1118 | { |
718e3744 | 1119 | switch (or->path_type) |
1120 | { | |
1121 | case OSPF_PATH_INTRA_AREA: | |
0c0f9cd5 | 1122 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 1123 | zlog_debug ("%s [%d] area: %s", |
0c0f9cd5 | 1124 | inet_ntop (AF_INET, &or->id, buf1, BUFSIZ), |
1125 | or->cost, inet_ntop (AF_INET, &or->u.std.area_id, | |
1126 | buf2, BUFSIZ)); | |
718e3744 | 1127 | break; |
1128 | case OSPF_PATH_INTER_AREA: | |
0c0f9cd5 | 1129 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 1130 | zlog_debug ("%s IA [%d] area: %s", |
0c0f9cd5 | 1131 | inet_ntop (AF_INET, &or->id, buf1, BUFSIZ), |
1132 | or->cost, inet_ntop (AF_INET, &or->u.std.area_id, | |
1133 | buf2, BUFSIZ)); | |
718e3744 | 1134 | break; |
1135 | default: | |
1136 | break; | |
1137 | } | |
1138 | ||
1eb8ef25 | 1139 | for (ALL_LIST_ELEMENTS_RO (or->paths, pnode, path)) |
718e3744 | 1140 | { |
718e3744 | 1141 | if (path->nexthop.s_addr == 0) |
0c0f9cd5 | 1142 | { |
1143 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1144 | zlog_debug (" directly attached to %s\r\n", |
baaea325 | 1145 | ifindex2ifname (path->ifindex), VRF_DEFAULT); |
0c0f9cd5 | 1146 | } |
1147 | else | |
1148 | { | |
1149 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1150 | zlog_debug (" via %s, %s\r\n", |
a8ba847f | 1151 | inet_ntoa (path->nexthop), |
baaea325 | 1152 | ifindex2ifname (path->ifindex), VRF_DEFAULT); |
0c0f9cd5 | 1153 | } |
718e3744 | 1154 | } |
1155 | } | |
1156 | ||
2a42e285 | 1157 | zlog_debug ("ospf_rtrs_print() end"); |
718e3744 | 1158 | } |
075e12f5 | 1159 | #endif |
718e3744 | 1160 | |
1161 | /* Calculating the shortest-path tree for an area. */ | |
b5a8894d | 1162 | static void ospf_spf_calculate(struct ospf *ospf, struct ospf_area *area, |
d62a17ae | 1163 | struct route_table *new_table, |
1164 | struct route_table *new_rtrs) | |
718e3744 | 1165 | { |
d62a17ae | 1166 | struct pqueue *candidate; |
1167 | struct vertex *v; | |
718e3744 | 1168 | |
d62a17ae | 1169 | if (IS_DEBUG_OSPF_EVENT) { |
1170 | zlog_debug("ospf_spf_calculate: Start"); | |
1171 | zlog_debug("ospf_spf_calculate: running Dijkstra for area %s", | |
1172 | inet_ntoa(area->area_id)); | |
1173 | } | |
718e3744 | 1174 | |
d62a17ae | 1175 | /* Check router-lsa-self. If self-router-lsa is not yet allocated, |
1176 | return this area's calculation. */ | |
1177 | if (!area->router_lsa_self) { | |
1178 | if (IS_DEBUG_OSPF_EVENT) | |
1179 | zlog_debug( | |
1180 | "ospf_spf_calculate: " | |
1181 | "Skip area %s's calculation due to empty router_lsa_self", | |
1182 | inet_ntoa(area->area_id)); | |
1183 | return; | |
1184 | } | |
718e3744 | 1185 | |
d62a17ae | 1186 | /* RFC2328 16.1. (1). */ |
1187 | /* Initialize the algorithm's data structures. */ | |
1188 | ||
1189 | /* This function scans all the LSA database and set the stat field to | |
1190 | * LSA_SPF_NOT_EXPLORED. */ | |
1191 | ospf_lsdb_clean_stat(area->lsdb); | |
1192 | /* Create a new heap for the candidates. */ | |
1193 | candidate = pqueue_create(); | |
1194 | candidate->cmp = cmp; | |
1195 | candidate->update = update_stat; | |
1196 | ||
1197 | /* Initialize the shortest-path tree to only the root (which is the | |
1198 | router doing the calculation). */ | |
1199 | ospf_spf_init(area); | |
1200 | v = area->spf; | |
1201 | /* Set LSA position to LSA_SPF_IN_SPFTREE. This vertex is the root of | |
1202 | * the | |
1203 | * spanning tree. */ | |
1204 | *(v->stat) = LSA_SPF_IN_SPFTREE; | |
1205 | ||
1206 | /* Set Area A's TransitCapability to FALSE. */ | |
1207 | area->transit = OSPF_TRANSIT_FALSE; | |
1208 | area->shortcut_capability = 1; | |
1209 | ||
1210 | for (;;) { | |
1211 | /* RFC2328 16.1. (2). */ | |
b5a8894d | 1212 | ospf_spf_next(v, ospf, area, candidate); |
d62a17ae | 1213 | |
1214 | /* RFC2328 16.1. (3). */ | |
1215 | /* If at this step the candidate list is empty, the shortest- | |
1216 | path tree (of transit vertices) has been completely built and | |
1217 | this stage of the procedure terminates. */ | |
1218 | if (candidate->size == 0) | |
1219 | break; | |
1220 | ||
1221 | /* Otherwise, choose the vertex belonging to the candidate list | |
1222 | that is closest to the root, and add it to the shortest-path | |
1223 | tree (removing it from the candidate list in the | |
1224 | process). */ | |
1225 | /* Extract from the candidates the node with the lower key. */ | |
1226 | v = (struct vertex *)pqueue_dequeue(candidate); | |
1227 | /* Update stat field in vertex. */ | |
1228 | *(v->stat) = LSA_SPF_IN_SPFTREE; | |
1229 | ||
1230 | ospf_vertex_add_parent(v); | |
1231 | ||
1232 | /* RFC2328 16.1. (4). */ | |
1233 | if (v->type == OSPF_VERTEX_ROUTER) | |
1234 | ospf_intra_add_router(new_rtrs, v, area); | |
1235 | else | |
1236 | ospf_intra_add_transit(new_table, v, area); | |
1237 | ||
1238 | /* RFC2328 16.1. (5). */ | |
1239 | /* Iterate the algorithm by returning to Step 2. */ | |
1240 | ||
1241 | } /* end loop until no more candidate vertices */ | |
1242 | ||
1243 | if (IS_DEBUG_OSPF_EVENT) { | |
1244 | ospf_spf_dump(area->spf, 0); | |
1245 | ospf_route_table_dump(new_table); | |
1246 | } | |
cf744958 | 1247 | |
d62a17ae | 1248 | /* Second stage of SPF calculation procedure's */ |
1249 | ospf_spf_process_stubs(area, area->spf, new_table, 0); | |
cf744958 | 1250 | |
d62a17ae | 1251 | /* Free candidate queue. */ |
1252 | pqueue_delete(candidate); | |
718e3744 | 1253 | |
d62a17ae | 1254 | ospf_vertex_dump(__func__, area->spf, 0, 1); |
1255 | /* Free nexthop information, canonical versions of which are attached | |
1256 | * the first level of router vertices attached to the root vertex, see | |
1257 | * ospf_nexthop_calculation. | |
1258 | */ | |
1259 | ospf_canonical_nexthops_free(area->spf); | |
718e3744 | 1260 | |
d62a17ae | 1261 | /* Increment SPF Calculation Counter. */ |
1262 | area->spf_calculation++; | |
1263 | ||
1264 | monotime(&area->ospf->ts_spf); | |
1265 | area->ts_spf = area->ospf->ts_spf; | |
cf744958 | 1266 | |
d62a17ae | 1267 | if (IS_DEBUG_OSPF_EVENT) |
1268 | zlog_debug("ospf_spf_calculate: Stop. %zd vertices", | |
1269 | mtype_stats_alloc(MTYPE_OSPF_VERTEX)); | |
1270 | ||
1271 | /* Free SPF vertices, but not the list. List has ospf_vertex_free | |
1272 | * as deconstructor. | |
1273 | */ | |
1274 | list_delete_all_node(&vertex_list); | |
718e3744 | 1275 | } |
6b0655a2 | 1276 | |
718e3744 | 1277 | /* Timer for SPF calculation. */ |
d62a17ae | 1278 | static int ospf_spf_calculate_timer(struct thread *thread) |
718e3744 | 1279 | { |
d62a17ae | 1280 | struct ospf *ospf = THREAD_ARG(thread); |
1281 | struct route_table *new_table, *new_rtrs; | |
1282 | struct ospf_area *area; | |
1283 | struct listnode *node, *nnode; | |
1284 | struct timeval start_time, spf_start_time; | |
1285 | int areas_processed = 0; | |
1286 | unsigned long ia_time, prune_time, rt_time; | |
1287 | unsigned long abr_time, total_spf_time, spf_time; | |
1288 | char rbuf[32]; /* reason_buf */ | |
1289 | ||
1290 | if (IS_DEBUG_OSPF_EVENT) | |
1291 | zlog_debug("SPF: Timer (SPF calculation expire)"); | |
1292 | ||
1293 | ospf->t_spf_calc = NULL; | |
1294 | ||
1295 | monotime(&spf_start_time); | |
1296 | /* Allocate new table tree. */ | |
1297 | new_table = route_table_init(); | |
1298 | new_rtrs = route_table_init(); | |
1299 | ||
1300 | ospf_vl_unapprove(ospf); | |
1301 | ||
1302 | /* Calculate SPF for each area. */ | |
1303 | for (ALL_LIST_ELEMENTS(ospf->areas, node, nnode, area)) { | |
1304 | /* Do backbone last, so as to first discover intra-area paths | |
1305 | * for any back-bone virtual-links | |
1306 | */ | |
1307 | if (ospf->backbone && ospf->backbone == area) | |
1308 | continue; | |
cf744958 | 1309 | |
b5a8894d | 1310 | ospf_spf_calculate(ospf, area, new_table, new_rtrs); |
d62a17ae | 1311 | areas_processed++; |
1312 | } | |
1313 | ||
1314 | /* SPF for backbone, if required */ | |
1315 | if (ospf->backbone) { | |
b5a8894d | 1316 | ospf_spf_calculate(ospf, ospf->backbone, new_table, new_rtrs); |
d62a17ae | 1317 | areas_processed++; |
1318 | } | |
1319 | ||
1320 | spf_time = monotime_since(&spf_start_time, NULL); | |
1321 | ||
1322 | ospf_vl_shut_unapproved(ospf); | |
1323 | ||
1324 | monotime(&start_time); | |
1325 | ospf_ia_routing(ospf, new_table, new_rtrs); | |
1326 | ia_time = monotime_since(&start_time, NULL); | |
1327 | ||
1328 | monotime(&start_time); | |
1329 | ospf_prune_unreachable_networks(new_table); | |
1330 | ospf_prune_unreachable_routers(new_rtrs); | |
1331 | prune_time = monotime_since(&start_time, NULL); | |
1332 | ||
1333 | /* AS-external-LSA calculation should not be performed here. */ | |
1334 | ||
1335 | /* If new Router Route is installed, | |
1336 | then schedule re-calculate External routes. */ | |
1337 | if (1) | |
1338 | ospf_ase_calculate_schedule(ospf); | |
1339 | ||
1340 | ospf_ase_calculate_timer_add(ospf); | |
1341 | ||
b5a8894d | 1342 | if (IS_DEBUG_OSPF_EVENT) |
996c9314 LB |
1343 | zlog_debug( |
1344 | "%s: ospf install new route, vrf %s id %u new_table count %lu", | |
1345 | __PRETTY_FUNCTION__, ospf_vrf_id_to_name(ospf->vrf_id), | |
1346 | ospf->vrf_id, new_table->count); | |
d62a17ae | 1347 | /* Update routing table. */ |
1348 | monotime(&start_time); | |
1349 | ospf_route_install(ospf, new_table); | |
1350 | rt_time = monotime_since(&start_time, NULL); | |
1351 | ||
1352 | /* Update ABR/ASBR routing table */ | |
1353 | if (ospf->old_rtrs) { | |
1354 | /* old_rtrs's node holds linked list of ospf_route. --kunihiro. | |
1355 | */ | |
1356 | /* ospf_route_delete (ospf->old_rtrs); */ | |
1357 | ospf_rtrs_free(ospf->old_rtrs); | |
1358 | } | |
1359 | ||
1360 | ospf->old_rtrs = ospf->new_rtrs; | |
1361 | ospf->new_rtrs = new_rtrs; | |
1362 | ||
1363 | monotime(&start_time); | |
1364 | if (IS_OSPF_ABR(ospf)) | |
1365 | ospf_abr_task(ospf); | |
1366 | abr_time = monotime_since(&start_time, NULL); | |
1367 | ||
cf9b9f77 OD |
1368 | /* Schedule Segment Routing update */ |
1369 | ospf_sr_update_timer_add(ospf); | |
1370 | ||
d62a17ae | 1371 | total_spf_time = |
1372 | monotime_since(&spf_start_time, &ospf->ts_spf_duration); | |
1373 | ||
1374 | rbuf[0] = '\0'; | |
1375 | if (spf_reason_flags) { | |
1376 | if (spf_reason_flags & SPF_FLAG_ROUTER_LSA_INSTALL) | |
1377 | strncat(rbuf, "R, ", sizeof(rbuf) - strlen(rbuf) - 1); | |
1378 | if (spf_reason_flags & SPF_FLAG_NETWORK_LSA_INSTALL) | |
1379 | strncat(rbuf, "N, ", sizeof(rbuf) - strlen(rbuf) - 1); | |
1380 | if (spf_reason_flags & SPF_FLAG_SUMMARY_LSA_INSTALL) | |
1381 | strncat(rbuf, "S, ", sizeof(rbuf) - strlen(rbuf) - 1); | |
1382 | if (spf_reason_flags & SPF_FLAG_ASBR_SUMMARY_LSA_INSTALL) | |
1383 | strncat(rbuf, "AS, ", sizeof(rbuf) - strlen(rbuf) - 1); | |
1384 | if (spf_reason_flags & SPF_FLAG_ABR_STATUS_CHANGE) | |
1385 | strncat(rbuf, "ABR, ", sizeof(rbuf) - strlen(rbuf) - 1); | |
1386 | if (spf_reason_flags & SPF_FLAG_ASBR_STATUS_CHANGE) | |
1387 | strncat(rbuf, "ASBR, ", | |
1388 | sizeof(rbuf) - strlen(rbuf) - 1); | |
1389 | if (spf_reason_flags & SPF_FLAG_MAXAGE) | |
1390 | strncat(rbuf, "M, ", sizeof(rbuf) - strlen(rbuf) - 1); | |
1391 | ||
1392 | size_t rbuflen = strlen(rbuf); | |
1393 | if (rbuflen >= 2) | |
1394 | rbuf[rbuflen - 2] = '\0'; /* skip the last ", " */ | |
1395 | else | |
1396 | rbuf[0] = '\0'; | |
1397 | } | |
1398 | ||
1399 | if (IS_DEBUG_OSPF_EVENT) { | |
1400 | zlog_info("SPF Processing Time(usecs): %ld", total_spf_time); | |
1401 | zlog_info("\t SPF Time: %ld", spf_time); | |
1402 | zlog_info("\t InterArea: %ld", ia_time); | |
1403 | zlog_info("\t Prune: %ld", prune_time); | |
1404 | zlog_info("\tRouteInstall: %ld", rt_time); | |
1405 | if (IS_OSPF_ABR(ospf)) | |
1406 | zlog_info("\t ABR: %ld (%d areas)", abr_time, | |
1407 | areas_processed); | |
1408 | zlog_info("Reason(s) for SPF: %s", rbuf); | |
1409 | } | |
1410 | ||
1411 | ospf_clear_spf_reason_flags(); | |
1412 | ||
1413 | return 0; | |
718e3744 | 1414 | } |
1415 | ||
1416 | /* Add schedule for SPF calculation. To avoid frequenst SPF calc, we | |
1417 | set timer for SPF calc. */ | |
d62a17ae | 1418 | void ospf_spf_calculate_schedule(struct ospf *ospf, ospf_spf_reason_t reason) |
718e3744 | 1419 | { |
d62a17ae | 1420 | unsigned long delay, elapsed, ht; |
718e3744 | 1421 | |
d62a17ae | 1422 | if (IS_DEBUG_OSPF_EVENT) |
1423 | zlog_debug("SPF: calculation timer scheduled"); | |
1424 | ||
1425 | /* OSPF instance does not exist. */ | |
1426 | if (ospf == NULL) | |
1427 | return; | |
1428 | ||
1429 | ospf_spf_set_reason(reason); | |
1430 | ||
1431 | /* SPF calculation timer is already scheduled. */ | |
1432 | if (ospf->t_spf_calc) { | |
1433 | if (IS_DEBUG_OSPF_EVENT) | |
1434 | zlog_debug( | |
1435 | "SPF: calculation timer is already scheduled: %p", | |
1436 | (void *)ospf->t_spf_calc); | |
1437 | return; | |
1438 | } | |
1439 | ||
1440 | elapsed = monotime_since(&ospf->ts_spf, NULL) / 1000; | |
1441 | ||
1442 | ht = ospf->spf_holdtime * ospf->spf_hold_multiplier; | |
1443 | ||
1444 | if (ht > ospf->spf_max_holdtime) | |
1445 | ht = ospf->spf_max_holdtime; | |
1446 | ||
1447 | /* Get SPF calculation delay time. */ | |
1448 | if (elapsed < ht) { | |
1449 | /* Got an event within the hold time of last SPF. We need to | |
1450 | * increase the hold_multiplier, if it's not already at/past | |
1451 | * maximum value, and wasn't already increased.. | |
1452 | */ | |
1453 | if (ht < ospf->spf_max_holdtime) | |
1454 | ospf->spf_hold_multiplier++; | |
1455 | ||
1456 | /* always honour the SPF initial delay */ | |
1457 | if ((ht - elapsed) < ospf->spf_delay) | |
1458 | delay = ospf->spf_delay; | |
1459 | else | |
1460 | delay = ht - elapsed; | |
1461 | } else { | |
1462 | /* Event is past required hold-time of last SPF */ | |
1463 | delay = ospf->spf_delay; | |
1464 | ospf->spf_hold_multiplier = 1; | |
1465 | } | |
1466 | ||
1467 | if (IS_DEBUG_OSPF_EVENT) | |
05ba78e4 | 1468 | zlog_debug("SPF: calculation timer delay = %ld msec", delay); |
cf744958 | 1469 | |
d62a17ae | 1470 | ospf->t_spf_calc = NULL; |
1471 | thread_add_timer_msec(master, ospf_spf_calculate_timer, ospf, delay, | |
1472 | &ospf->t_spf_calc); | |
718e3744 | 1473 | } |