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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; | |
eb3da6df | 175 | new->children = list_new (); |
176 | new->parents = list_new (); | |
9c27ef9b PJ |
177 | new->parents->del = vertex_parent_free; |
178 | ||
179 | listnode_add (&vertex_list, new); | |
eb3da6df | 180 | |
9c27ef9b PJ |
181 | if (IS_DEBUG_OSPF_EVENT) |
182 | zlog_debug ("%s: Created %s vertex %s", __func__, | |
183 | new->type == OSPF_VERTEX_ROUTER ? "Router" : "Network", | |
184 | inet_ntoa (new->lsa->id)); | |
718e3744 | 185 | return new; |
186 | } | |
187 | ||
4dadc291 | 188 | static void |
9c27ef9b | 189 | ospf_vertex_free (void *data) |
718e3744 | 190 | { |
9c27ef9b | 191 | struct vertex *v = data; |
eb3da6df | 192 | |
9c27ef9b PJ |
193 | if (IS_DEBUG_OSPF_EVENT) |
194 | zlog_debug ("%s: Free %s vertex %s", __func__, | |
195 | v->type == OSPF_VERTEX_ROUTER ? "Router" : "Network", | |
196 | inet_ntoa (v->lsa->id)); | |
7461d459 | 197 | |
9c27ef9b PJ |
198 | /* There should be no parents potentially holding references to this vertex |
199 | * Children however may still be there, but presumably referenced by other | |
200 | * vertices | |
eb3da6df | 201 | */ |
9c27ef9b | 202 | //assert (listcount (v->parents) == 0); |
eb3da6df | 203 | |
9c27ef9b PJ |
204 | if (v->children) |
205 | list_delete (v->children); | |
206 | v->children = NULL; | |
207 | ||
208 | if (v->parents) | |
209 | list_delete (v->parents); | |
eb3da6df | 210 | v->parents = NULL; |
211 | ||
212 | v->lsa = NULL; | |
7461d459 | 213 | |
718e3744 | 214 | XFREE (MTYPE_OSPF_VERTEX, v); |
215 | } | |
216 | ||
4dadc291 | 217 | static void |
eb1ce605 | 218 | ospf_vertex_dump(const char *msg, struct vertex *v, |
eb3da6df | 219 | int print_parents, int print_children) |
630e4807 | 220 | { |
221 | if ( ! IS_DEBUG_OSPF_EVENT) | |
222 | return; | |
223 | ||
eb3da6df | 224 | zlog_debug("%s %s vertex %s distance %u flags %u", |
630e4807 | 225 | msg, |
226 | v->type == OSPF_VERTEX_ROUTER ? "Router" : "Network", | |
227 | inet_ntoa(v->lsa->id), | |
228 | v->distance, | |
630e4807 | 229 | (unsigned int)v->flags); |
230 | ||
eb3da6df | 231 | if (print_parents) |
630e4807 | 232 | { |
1eb8ef25 | 233 | struct listnode *node; |
eb3da6df | 234 | struct vertex_parent *vp; |
1eb8ef25 | 235 | |
eb3da6df | 236 | for (ALL_LIST_ELEMENTS_RO (v->parents, node, vp)) |
630e4807 | 237 | { |
238 | char buf1[BUFSIZ]; | |
eb3da6df | 239 | |
240 | if (vp) | |
630e4807 | 241 | { |
eb3da6df | 242 | zlog_debug ("parent %s backlink %d nexthop %s interface %s", |
243 | inet_ntoa(vp->parent->lsa->id), vp->backlink, | |
244 | inet_ntop(AF_INET, &vp->nexthop->router, buf1, BUFSIZ), | |
245 | vp->nexthop->oi ? IF_NAME(vp->nexthop->oi) : "NULL"); | |
630e4807 | 246 | } |
247 | } | |
248 | } | |
249 | ||
250 | if (print_children) | |
251 | { | |
52dc7ee6 | 252 | struct listnode *cnode; |
1eb8ef25 | 253 | struct vertex *cv; |
254 | ||
eb3da6df | 255 | for (ALL_LIST_ELEMENTS_RO (v->children, cnode, cv)) |
1eb8ef25 | 256 | ospf_vertex_dump(" child:", cv, 0, 0); |
630e4807 | 257 | } |
258 | } | |
259 | ||
260 | ||
261 | /* Add a vertex to the list of children in each of its parents. */ | |
4dadc291 | 262 | static void |
718e3744 | 263 | ospf_vertex_add_parent (struct vertex *v) |
264 | { | |
eb3da6df | 265 | struct vertex_parent *vp; |
52dc7ee6 | 266 | struct listnode *node; |
7461d459 | 267 | |
9c27ef9b | 268 | assert (v && v->parents); |
7461d459 | 269 | |
eb3da6df | 270 | for (ALL_LIST_ELEMENTS_RO (v->parents, node, vp)) |
718e3744 | 271 | { |
eb3da6df | 272 | assert (vp->parent && vp->parent->children); |
7461d459 | 273 | |
718e3744 | 274 | /* No need to add two links from the same parent. */ |
eb3da6df | 275 | if (listnode_lookup (vp->parent->children, v) == NULL) |
276 | listnode_add (vp->parent->children, v); | |
718e3744 | 277 | } |
278 | } | |
279 | \f | |
4dadc291 | 280 | static void |
718e3744 | 281 | ospf_spf_init (struct ospf_area *area) |
282 | { | |
283 | struct vertex *v; | |
9c27ef9b | 284 | |
718e3744 | 285 | /* Create root node. */ |
286 | v = ospf_vertex_new (area->router_lsa_self); | |
bd34fb34 | 287 | |
718e3744 | 288 | area->spf = v; |
289 | ||
290 | /* Reset ABR and ASBR router counts. */ | |
291 | area->abr_count = 0; | |
292 | area->asbr_count = 0; | |
293 | } | |
294 | ||
d355bfa7 | 295 | /* return index of link back to V from W, or -1 if no link found */ |
4dadc291 | 296 | static int |
718e3744 | 297 | ospf_lsa_has_link (struct lsa_header *w, struct lsa_header *v) |
298 | { | |
eb1ce605 | 299 | unsigned int i, length; |
718e3744 | 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 | { | |
306 | if (v->type == OSPF_NETWORK_LSA) | |
d355bfa7 | 307 | return -1; |
718e3744 | 308 | |
309 | nl = (struct network_lsa *) w; | |
310 | length = (ntohs (w->length) - OSPF_LSA_HEADER_SIZE - 4) / 4; | |
0c0f9cd5 | 311 | |
718e3744 | 312 | for (i = 0; i < length; i++) |
313 | if (IPV4_ADDR_SAME (&nl->routers[i], &v->id)) | |
d355bfa7 | 314 | return i; |
315 | return -1; | |
718e3744 | 316 | } |
317 | ||
318 | /* In case of W is Router LSA. */ | |
319 | if (w->type == OSPF_ROUTER_LSA) | |
320 | { | |
321 | rl = (struct router_lsa *) w; | |
322 | ||
323 | length = ntohs (w->length); | |
324 | ||
325 | for (i = 0; | |
0c0f9cd5 | 326 | i < ntohs (rl->links) && length >= sizeof (struct router_lsa); |
327 | i++, length -= 12) | |
718e3744 | 328 | { |
329 | switch (rl->link[i].type) | |
330 | { | |
331 | case LSA_LINK_TYPE_POINTOPOINT: | |
332 | case LSA_LINK_TYPE_VIRTUALLINK: | |
333 | /* Router LSA ID. */ | |
334 | if (v->type == OSPF_ROUTER_LSA && | |
335 | IPV4_ADDR_SAME (&rl->link[i].link_id, &v->id)) | |
336 | { | |
d355bfa7 | 337 | return i; |
718e3744 | 338 | } |
339 | break; | |
340 | case LSA_LINK_TYPE_TRANSIT: | |
341 | /* Network LSA ID. */ | |
342 | if (v->type == OSPF_NETWORK_LSA && | |
343 | IPV4_ADDR_SAME (&rl->link[i].link_id, &v->id)) | |
344 | { | |
d355bfa7 | 345 | return i; |
0c0f9cd5 | 346 | } |
718e3744 | 347 | break; |
348 | case LSA_LINK_TYPE_STUB: | |
eb3da6df | 349 | /* Stub can't lead anywhere, carry on */ |
718e3744 | 350 | continue; |
351 | default: | |
352 | break; | |
353 | } | |
354 | } | |
355 | } | |
d355bfa7 | 356 | return -1; |
718e3744 | 357 | } |
358 | ||
718e3744 | 359 | #define ROUTER_LSA_MIN_SIZE 12 |
360 | #define ROUTER_LSA_TOS_SIZE 4 | |
361 | ||
630e4807 | 362 | /* Find the next link after prev_link from v to w. If prev_link is |
363 | * NULL, return the first link from v to w. Ignore stub and virtual links; | |
364 | * these link types will never be returned. | |
365 | */ | |
4dadc291 | 366 | static struct router_lsa_link * |
718e3744 | 367 | ospf_get_next_link (struct vertex *v, struct vertex *w, |
0c0f9cd5 | 368 | struct router_lsa_link *prev_link) |
718e3744 | 369 | { |
370 | u_char *p; | |
371 | u_char *lim; | |
bd540377 | 372 | u_char lsa_type = LSA_LINK_TYPE_TRANSIT; |
718e3744 | 373 | struct router_lsa_link *l; |
374 | ||
bd540377 JT |
375 | if (w->type == OSPF_VERTEX_ROUTER) |
376 | lsa_type = LSA_LINK_TYPE_POINTOPOINT; | |
377 | ||
718e3744 | 378 | if (prev_link == NULL) |
630e4807 | 379 | p = ((u_char *) v->lsa) + OSPF_LSA_HEADER_SIZE + 4; |
718e3744 | 380 | else |
381 | { | |
0c0f9cd5 | 382 | p = (u_char *) prev_link; |
718e3744 | 383 | p += (ROUTER_LSA_MIN_SIZE + |
384 | (prev_link->m[0].tos_count * ROUTER_LSA_TOS_SIZE)); | |
385 | } | |
0c0f9cd5 | 386 | |
718e3744 | 387 | lim = ((u_char *) v->lsa) + ntohs (v->lsa->length); |
388 | ||
389 | while (p < lim) | |
390 | { | |
391 | l = (struct router_lsa_link *) p; | |
392 | ||
0c0f9cd5 | 393 | p += (ROUTER_LSA_MIN_SIZE + (l->m[0].tos_count * ROUTER_LSA_TOS_SIZE)); |
718e3744 | 394 | |
bd540377 | 395 | if (l->m[0].type != lsa_type) |
0c0f9cd5 | 396 | continue; |
718e3744 | 397 | |
398 | if (IPV4_ADDR_SAME (&l->link_id, &w->id)) | |
0c0f9cd5 | 399 | return l; |
718e3744 | 400 | } |
401 | ||
402 | return NULL; | |
403 | } | |
404 | ||
bc20c1a4 PJ |
405 | static void |
406 | ospf_spf_flush_parents (struct vertex *w) | |
407 | { | |
408 | struct vertex_parent *vp; | |
409 | struct listnode *ln, *nn; | |
410 | ||
411 | /* delete the existing nexthops */ | |
412 | for (ALL_LIST_ELEMENTS (w->parents, ln, nn, vp)) | |
413 | { | |
414 | list_delete_node (w->parents, ln); | |
415 | vertex_parent_free (vp); | |
416 | } | |
417 | } | |
418 | ||
75ee0b8e | 419 | /* |
420 | * Consider supplied next-hop for inclusion to the supplied list of | |
421 | * equal-cost next-hops, adjust list as neccessary. | |
bf9392c6 | 422 | */ |
4dadc291 | 423 | static void |
eb3da6df | 424 | ospf_spf_add_parent (struct vertex *v, struct vertex *w, |
bc20c1a4 | 425 | struct vertex_nexthop *newhop, |
bd34fb34 | 426 | unsigned int distance) |
bf9392c6 | 427 | { |
eb3da6df | 428 | struct vertex_parent *vp; |
429 | ||
08d3d5b3 | 430 | /* we must have a newhop, and a distance */ |
bd34fb34 | 431 | assert (v && w && newhop); |
08d3d5b3 | 432 | assert (distance); |
eb3da6df | 433 | |
08d3d5b3 PJ |
434 | /* IFF w has already been assigned a distance, then we shouldn't get here |
435 | * unless callers have determined V(l)->W is shortest / equal-shortest | |
436 | * path (0 is a special case distance (no distance yet assigned)). | |
bc20c1a4 | 437 | */ |
08d3d5b3 PJ |
438 | if (w->distance) |
439 | assert (distance <= w->distance); | |
440 | else | |
441 | w->distance = distance; | |
bc20c1a4 | 442 | |
b75ae99e PJ |
443 | if (IS_DEBUG_OSPF_EVENT) |
444 | { | |
445 | char buf[2][INET_ADDRSTRLEN]; | |
446 | zlog_debug ("%s: Adding %s as parent of %s", | |
447 | __func__, | |
448 | inet_ntop(AF_INET, &v->lsa->id, buf[0], sizeof(buf[0])), | |
449 | inet_ntop(AF_INET, &w->lsa->id, buf[1], sizeof(buf[1]))); | |
450 | } | |
451 | ||
bc20c1a4 | 452 | /* Adding parent for a new, better path: flush existing parents from W. */ |
bd34fb34 | 453 | if (distance < w->distance) |
bc20c1a4 | 454 | { |
b75ae99e PJ |
455 | if (IS_DEBUG_OSPF_EVENT) |
456 | zlog_debug ("%s: distance %d better than %d, flushing existing parents", | |
457 | __func__, distance, w->distance); | |
bc20c1a4 | 458 | ospf_spf_flush_parents (w); |
bd34fb34 | 459 | w->distance = distance; |
bc20c1a4 PJ |
460 | } |
461 | ||
462 | /* new parent is <= existing parents, add it to parent list */ | |
eb3da6df | 463 | vp = vertex_parent_new (v, ospf_lsa_has_link (w->lsa, v->lsa), newhop); |
464 | listnode_add (w->parents, vp); | |
0c0f9cd5 | 465 | |
eb3da6df | 466 | return; |
467 | } | |
468 | ||
630e4807 | 469 | /* 16.1.1. Calculate nexthop from root through V (parent) to |
bd34fb34 | 470 | * vertex W (destination), with given distance from root->W. |
eb3da6df | 471 | * |
472 | * The link must be supplied if V is the root vertex. In all other cases | |
473 | * it may be NULL. | |
bd34fb34 PJ |
474 | * |
475 | * Note that this function may fail, hence the state of the destination | |
476 | * vertex, W, should /not/ be modified in a dependent manner until | |
477 | * this function returns. This function will update the W vertex with the | |
478 | * provided distance as appropriate. | |
630e4807 | 479 | */ |
bc20c1a4 | 480 | static unsigned int |
eb3da6df | 481 | ospf_nexthop_calculation (struct ospf_area *area, struct vertex *v, |
bd34fb34 PJ |
482 | struct vertex *w, struct router_lsa_link *l, |
483 | unsigned int distance) | |
718e3744 | 484 | { |
1eb8ef25 | 485 | struct listnode *node, *nnode; |
eb3da6df | 486 | struct vertex_nexthop *nh; |
487 | struct vertex_parent *vp; | |
718e3744 | 488 | struct ospf_interface *oi = NULL; |
bc20c1a4 | 489 | unsigned int added = 0; |
0c0f9cd5 | 490 | |
718e3744 | 491 | if (IS_DEBUG_OSPF_EVENT) |
630e4807 | 492 | { |
2a42e285 | 493 | zlog_debug ("ospf_nexthop_calculation(): Start"); |
630e4807 | 494 | ospf_vertex_dump("V (parent):", v, 1, 1); |
495 | ospf_vertex_dump("W (dest) :", w, 1, 1); | |
bd34fb34 | 496 | zlog_debug ("V->W distance: %d", distance); |
630e4807 | 497 | } |
718e3744 | 498 | |
718e3744 | 499 | if (v == area->spf) |
9c27ef9b | 500 | { |
630e4807 | 501 | /* 16.1.1 para 4. In the first case, the parent vertex (V) is the |
502 | root (the calculating router itself). This means that the | |
503 | destination is either a directly connected network or directly | |
504 | connected router. The outgoing interface in this case is simply | |
505 | the OSPF interface connecting to the destination network/router. | |
506 | */ | |
507 | ||
718e3744 | 508 | if (w->type == OSPF_VERTEX_ROUTER) |
0c0f9cd5 | 509 | { |
eb3da6df | 510 | /* l is a link from v to w |
511 | * l2 will be link from w to v | |
512 | */ | |
513 | struct router_lsa_link *l2 = NULL; | |
514 | ||
515 | /* we *must* be supplied with the link data */ | |
516 | assert (l != NULL); | |
517 | ||
518 | if (IS_DEBUG_OSPF_EVENT) | |
0c0f9cd5 | 519 | { |
eb3da6df | 520 | char buf1[BUFSIZ]; |
521 | char buf2[BUFSIZ]; | |
522 | ||
523 | zlog_debug("ospf_nexthop_calculation(): considering link " | |
524 | "type %d link_id %s link_data %s", | |
525 | l->m[0].type, | |
526 | inet_ntop (AF_INET, &l->link_id, buf1, BUFSIZ), | |
527 | inet_ntop (AF_INET, &l->link_data, buf2, BUFSIZ)); | |
528 | } | |
529 | ||
530 | if (l->m[0].type == LSA_LINK_TYPE_POINTOPOINT) | |
531 | { | |
532 | /* If the destination is a router which connects to | |
533 | the calculating router via a Point-to-MultiPoint | |
534 | network, the destination's next hop IP address(es) | |
535 | can be determined by examining the destination's | |
536 | router-LSA: each link pointing back to the | |
537 | calculating router and having a Link Data field | |
538 | belonging to the Point-to-MultiPoint network | |
539 | provides an IP address of the next hop router. | |
540 | ||
541 | At this point l is a link from V to W, and V is the | |
542 | root ("us"). Find the local interface associated | |
543 | with l (its address is in l->link_data). If it | |
544 | is a point-to-multipoint interface, then look through | |
545 | the links in the opposite direction (W to V). If | |
546 | any of them have an address that lands within the | |
547 | subnet declared by the PtMP link, then that link | |
548 | is a constituent of the PtMP link, and its address is | |
549 | a nexthop address for V. | |
550 | */ | |
551 | oi = ospf_if_is_configured (area->ospf, &l->link_data); | |
552 | if (oi && oi->type == OSPF_IFTYPE_POINTOMULTIPOINT) | |
0c0f9cd5 | 553 | { |
eb3da6df | 554 | struct prefix_ipv4 la; |
555 | ||
556 | la.family = AF_INET; | |
557 | la.prefixlen = oi->address->prefixlen; | |
558 | ||
559 | /* V links to W on PtMP interface | |
560 | - find the interface address on W */ | |
561 | while ((l2 = ospf_get_next_link (w, v, l2))) | |
0c0f9cd5 | 562 | { |
eb3da6df | 563 | la.prefix = l2->link_data; |
0c0f9cd5 | 564 | |
eb3da6df | 565 | if (prefix_cmp ((struct prefix *) &la, |
566 | oi->address) == 0) | |
567 | /* link_data is on our PtMP network */ | |
568 | break; | |
569 | } | |
570 | } /* end l is on point-to-multipoint link */ | |
571 | else | |
572 | { | |
573 | /* l is a regular point-to-point link. | |
574 | Look for a link from W to V. | |
575 | */ | |
576 | while ((l2 = ospf_get_next_link (w, v, l2))) | |
0c0f9cd5 | 577 | { |
eb3da6df | 578 | oi = ospf_if_is_configured (area->ospf, |
579 | &(l2->link_data)); | |
580 | ||
581 | if (oi == NULL) | |
582 | continue; | |
583 | ||
584 | if (!IPV4_ADDR_SAME (&oi->address->u.prefix4, | |
585 | &l->link_data)) | |
586 | continue; | |
587 | ||
588 | break; | |
0c0f9cd5 | 589 | } |
eb3da6df | 590 | } |
591 | ||
592 | if (oi && l2) | |
593 | { | |
594 | /* found all necessary info to build nexthop */ | |
595 | nh = vertex_nexthop_new (); | |
596 | nh->oi = oi; | |
597 | nh->router = l2->link_data; | |
bd34fb34 | 598 | ospf_spf_add_parent (v, w, nh, distance); |
bc20c1a4 | 599 | return 1; |
eb3da6df | 600 | } |
601 | else | |
9c27ef9b PJ |
602 | zlog_info("ospf_nexthop_calculation(): " |
603 | "could not determine nexthop for link"); | |
604 | } /* end point-to-point link from V to W */ | |
605 | else if (l->m[0].type == LSA_LINK_TYPE_VIRTUALLINK) | |
606 | { | |
607 | struct ospf_vl_data *vl_data; | |
608 | ||
609 | /* VLink implementation limitations: | |
610 | * a) vl_data can only reference one nexthop, so no ECMP | |
611 | * to backbone through VLinks. Though transit-area | |
612 | * summaries may be considered, and those can be ECMP. | |
613 | * b) We can only use /one/ VLink, even if multiple ones | |
614 | * exist this router through multiple transit-areas. | |
615 | */ | |
616 | vl_data = ospf_vl_lookup (area->ospf, NULL, l->link_id); | |
617 | ||
618 | if (vl_data | |
619 | && CHECK_FLAG (vl_data->flags, OSPF_VL_FLAG_APPROVED)) | |
eb3da6df | 620 | { |
9c27ef9b PJ |
621 | nh = vertex_nexthop_new (); |
622 | nh->oi = vl_data->nexthop.oi; | |
623 | nh->router = vl_data->nexthop.router; | |
bd34fb34 | 624 | ospf_spf_add_parent (v, w, nh, distance); |
bc20c1a4 | 625 | return 1; |
eb3da6df | 626 | } |
9c27ef9b | 627 | else |
bc20c1a4 PJ |
628 | zlog_info("ospf_nexthop_calculation(): " |
629 | "vl_data for VL link not found"); | |
9c27ef9b | 630 | } /* end virtual-link from V to W */ |
bc20c1a4 | 631 | return 0; |
630e4807 | 632 | } /* end W is a Router vertex */ |
718e3744 | 633 | else |
0c0f9cd5 | 634 | { |
eb3da6df | 635 | assert(w->type == OSPF_VERTEX_NETWORK); |
636 | oi = ospf_if_is_configured (area->ospf, &(l->link_data)); | |
637 | if (oi) | |
0c0f9cd5 | 638 | { |
eb3da6df | 639 | nh = vertex_nexthop_new (); |
640 | nh->oi = oi; | |
641 | nh->router.s_addr = 0; | |
bd34fb34 | 642 | ospf_spf_add_parent (v, w, nh, distance); |
bc20c1a4 | 643 | return 1; |
0c0f9cd5 | 644 | } |
645 | } | |
9c27ef9b PJ |
646 | zlog_info("ospf_nexthop_calculation(): " |
647 | "Unknown attached link"); | |
bc20c1a4 | 648 | return 0; |
630e4807 | 649 | } /* end V is the root */ |
630e4807 | 650 | /* Check if W's parent is a network connected to root. */ |
718e3744 | 651 | else if (v->type == OSPF_VERTEX_NETWORK) |
652 | { | |
630e4807 | 653 | /* See if any of V's parents are the root. */ |
eb3da6df | 654 | for (ALL_LIST_ELEMENTS (v->parents, node, nnode, vp)) |
718e3744 | 655 | { |
eb3da6df | 656 | if (vp->parent == area->spf) /* connects to root? */ |
630e4807 | 657 | { |
658 | /* 16.1.1 para 5. ...the parent vertex is a network that | |
659 | * directly connects the calculating router to the destination | |
660 | * router. The list of next hops is then determined by | |
661 | * examining the destination's router-LSA... | |
662 | */ | |
663 | ||
664 | assert(w->type == OSPF_VERTEX_ROUTER); | |
0c0f9cd5 | 665 | while ((l = ospf_get_next_link (w, v, l))) |
666 | { | |
630e4807 | 667 | /* ...For each link in the router-LSA that points back to the |
668 | * parent network, the link's Link Data field provides the IP | |
669 | * address of a next hop router. The outgoing interface to | |
670 | * use can then be derived from the next hop IP address (or | |
671 | * it can be inherited from the parent network). | |
672 | */ | |
eb3da6df | 673 | nh = vertex_nexthop_new (); |
674 | nh->oi = vp->nexthop->oi; | |
675 | nh->router = l->link_data; | |
bc20c1a4 | 676 | added = 1; |
bd34fb34 | 677 | ospf_spf_add_parent (v, w, nh, distance); |
0c0f9cd5 | 678 | } |
0c0f9cd5 | 679 | } |
718e3744 | 680 | } |
85ef784e PJ |
681 | if (added) |
682 | return added; | |
718e3744 | 683 | } |
684 | ||
630e4807 | 685 | /* 16.1.1 para 4. If there is at least one intervening router in the |
686 | * current shortest path between the destination and the root, the | |
687 | * destination simply inherits the set of next hops from the | |
688 | * parent. | |
689 | */ | |
b75ae99e PJ |
690 | if (IS_DEBUG_OSPF_EVENT) |
691 | zlog_debug ("%s: Intervening routers, adding parent(s)", __func__); | |
692 | ||
eb3da6df | 693 | for (ALL_LIST_ELEMENTS (v->parents, node, nnode, vp)) |
bc20c1a4 PJ |
694 | { |
695 | added = 1; | |
bd34fb34 | 696 | ospf_spf_add_parent (v, w, vp->nexthop, distance); |
bc20c1a4 | 697 | } |
9c27ef9b | 698 | |
bc20c1a4 | 699 | return added; |
718e3744 | 700 | } |
701 | ||
630e4807 | 702 | /* RFC2328 Section 16.1 (2). |
703 | * v is on the SPF tree. Examine the links in v's LSA. Update the list | |
704 | * of candidates with any vertices not already on the list. If a lower-cost | |
705 | * path is found to a vertex already on the candidate list, store the new cost. | |
706 | */ | |
4dadc291 | 707 | static void |
718e3744 | 708 | ospf_spf_next (struct vertex *v, struct ospf_area *area, |
462f20d5 | 709 | struct pqueue * candidate) |
718e3744 | 710 | { |
711 | struct ospf_lsa *w_lsa = NULL; | |
718e3744 | 712 | u_char *p; |
713 | u_char *lim; | |
714 | struct router_lsa_link *l = NULL; | |
715 | struct in_addr *r; | |
718e3744 | 716 | int type = 0; |
717 | ||
718 | /* If this is a router-LSA, and bit V of the router-LSA (see Section | |
719 | A.4.2:RFC2328) is set, set Area A's TransitCapability to TRUE. */ | |
720 | if (v->type == OSPF_VERTEX_ROUTER) | |
721 | { | |
722 | if (IS_ROUTER_LSA_VIRTUAL ((struct router_lsa *) v->lsa)) | |
723 | area->transit = OSPF_TRANSIT_TRUE; | |
724 | } | |
b75ae99e PJ |
725 | |
726 | if (IS_DEBUG_OSPF_EVENT) | |
727 | zlog_debug ("%s: Next vertex of %s vertex %s", | |
728 | __func__, | |
729 | v->type == OSPF_VERTEX_ROUTER ? "Router" : "Network", | |
730 | inet_ntoa(v->lsa->id)); | |
731 | ||
718e3744 | 732 | p = ((u_char *) v->lsa) + OSPF_LSA_HEADER_SIZE + 4; |
0c0f9cd5 | 733 | lim = ((u_char *) v->lsa) + ntohs (v->lsa->length); |
734 | ||
718e3744 | 735 | while (p < lim) |
736 | { | |
eb3da6df | 737 | struct vertex *w; |
738 | unsigned int distance; | |
d355bfa7 | 739 | |
718e3744 | 740 | /* In case of V is Router-LSA. */ |
741 | if (v->lsa->type == OSPF_ROUTER_LSA) | |
742 | { | |
743 | l = (struct router_lsa_link *) p; | |
744 | ||
0c0f9cd5 | 745 | p += (ROUTER_LSA_MIN_SIZE + |
718e3744 | 746 | (l->m[0].tos_count * ROUTER_LSA_TOS_SIZE)); |
747 | ||
748 | /* (a) If this is a link to a stub network, examine the next | |
749 | link in V's LSA. Links to stub networks will be | |
750 | considered in the second stage of the shortest path | |
751 | calculation. */ | |
752 | if ((type = l->m[0].type) == LSA_LINK_TYPE_STUB) | |
753 | continue; | |
08d3d5b3 PJ |
754 | |
755 | /* Infinite distance links shouldn't be followed, except | |
756 | * for local links (a stub-routed router still wants to | |
757 | * calculate tree, so must follow its own links). | |
758 | */ | |
759 | if ((v != area->spf) && l->m[0].metric >= OSPF_OUTPUT_COST_INFINITE) | |
760 | continue; | |
718e3744 | 761 | |
762 | /* (b) Otherwise, W is a transit vertex (router or transit | |
763 | network). Look up the vertex W's LSA (router-LSA or | |
764 | network-LSA) in Area A's link state database. */ | |
765 | switch (type) | |
766 | { | |
767 | case LSA_LINK_TYPE_POINTOPOINT: | |
768 | case LSA_LINK_TYPE_VIRTUALLINK: | |
769 | if (type == LSA_LINK_TYPE_VIRTUALLINK) | |
0c0f9cd5 | 770 | { |
771 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 772 | zlog_debug ("looking up LSA through VL: %s", |
0c0f9cd5 | 773 | inet_ntoa (l->link_id)); |
774 | } | |
718e3744 | 775 | |
776 | w_lsa = ospf_lsa_lookup (area, OSPF_ROUTER_LSA, l->link_id, | |
777 | l->link_id); | |
778 | if (w_lsa) | |
0c0f9cd5 | 779 | { |
780 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 781 | zlog_debug ("found Router LSA %s", inet_ntoa (l->link_id)); |
0c0f9cd5 | 782 | } |
718e3744 | 783 | break; |
784 | case LSA_LINK_TYPE_TRANSIT: | |
0c0f9cd5 | 785 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 786 | zlog_debug ("Looking up Network LSA, ID: %s", |
0c0f9cd5 | 787 | inet_ntoa (l->link_id)); |
718e3744 | 788 | w_lsa = ospf_lsa_lookup_by_id (area, OSPF_NETWORK_LSA, |
0c0f9cd5 | 789 | l->link_id); |
718e3744 | 790 | if (w_lsa) |
0c0f9cd5 | 791 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 792 | zlog_debug ("found the LSA"); |
718e3744 | 793 | break; |
794 | default: | |
0c0f9cd5 | 795 | zlog_warn ("Invalid LSA link type %d", type); |
718e3744 | 796 | continue; |
797 | } | |
798 | } | |
799 | else | |
800 | { | |
801 | /* In case of V is Network-LSA. */ | |
0c0f9cd5 | 802 | r = (struct in_addr *) p; |
718e3744 | 803 | p += sizeof (struct in_addr); |
804 | ||
805 | /* Lookup the vertex W's LSA. */ | |
806 | w_lsa = ospf_lsa_lookup_by_id (area, OSPF_ROUTER_LSA, *r); | |
b75ae99e PJ |
807 | if (w_lsa) |
808 | { | |
809 | if (IS_DEBUG_OSPF_EVENT) | |
810 | zlog_debug ("found Router LSA %s", inet_ntoa (w_lsa->data->id)); | |
811 | } | |
718e3744 | 812 | } |
813 | ||
814 | /* (b cont.) If the LSA does not exist, or its LS age is equal | |
815 | to MaxAge, or it does not have a link back to vertex V, | |
816 | examine the next link in V's LSA.[23] */ | |
817 | if (w_lsa == NULL) | |
b75ae99e PJ |
818 | { |
819 | if (IS_DEBUG_OSPF_EVENT) | |
820 | zlog_debug ("No LSA found"); | |
821 | continue; | |
822 | } | |
718e3744 | 823 | |
824 | if (IS_LSA_MAXAGE (w_lsa)) | |
b75ae99e PJ |
825 | { |
826 | if (IS_DEBUG_OSPF_EVENT) | |
827 | zlog_debug ("LSA is MaxAge"); | |
828 | continue; | |
829 | } | |
718e3744 | 830 | |
eb3da6df | 831 | if (ospf_lsa_has_link (w_lsa->data, v->lsa) < 0 ) |
718e3744 | 832 | { |
0c0f9cd5 | 833 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 834 | zlog_debug ("The LSA doesn't have a link back"); |
718e3744 | 835 | continue; |
836 | } | |
837 | ||
838 | /* (c) If vertex W is already on the shortest-path tree, examine | |
839 | the next link in the LSA. */ | |
462f20d5 | 840 | if (w_lsa->stat == LSA_SPF_IN_SPFTREE) |
841 | { | |
842 | if (IS_DEBUG_OSPF_EVENT) | |
843 | zlog_debug ("The LSA is already in SPF"); | |
844 | continue; | |
845 | } | |
718e3744 | 846 | |
847 | /* (d) Calculate the link state cost D of the resulting path | |
848 | from the root to vertex W. D is equal to the sum of the link | |
849 | state cost of the (already calculated) shortest path to | |
850 | vertex V and the advertised cost of the link between vertices | |
851 | V and W. If D is: */ | |
852 | ||
718e3744 | 853 | /* calculate link cost D. */ |
854 | if (v->lsa->type == OSPF_ROUTER_LSA) | |
eb3da6df | 855 | distance = v->distance + ntohs (l->m[0].metric); |
630e4807 | 856 | else /* v is not a Router-LSA */ |
eb3da6df | 857 | distance = v->distance; |
718e3744 | 858 | |
859 | /* Is there already vertex W in candidate list? */ | |
462f20d5 | 860 | if (w_lsa->stat == LSA_SPF_NOT_EXPLORED) |
861 | { | |
eb3da6df | 862 | /* prepare vertex W. */ |
863 | w = ospf_vertex_new (w_lsa); | |
864 | ||
462f20d5 | 865 | /* Calculate nexthop to W. */ |
bd34fb34 | 866 | if (ospf_nexthop_calculation (area, v, w, l, distance)) |
bc20c1a4 | 867 | pqueue_enqueue (w, candidate); |
b75ae99e PJ |
868 | else if (IS_DEBUG_OSPF_EVENT) |
869 | zlog_debug ("Nexthop Calc failed"); | |
462f20d5 | 870 | } |
871 | else if (w_lsa->stat >= 0) | |
872 | { | |
873 | /* Get the vertex from candidates. */ | |
eb3da6df | 874 | w = candidate->array[w_lsa->stat]; |
718e3744 | 875 | |
462f20d5 | 876 | /* if D is greater than. */ |
eb3da6df | 877 | if (w->distance < distance) |
718e3744 | 878 | { |
718e3744 | 879 | continue; |
880 | } | |
462f20d5 | 881 | /* equal to. */ |
eb3da6df | 882 | else if (w->distance == distance) |
718e3744 | 883 | { |
eb3da6df | 884 | /* Found an equal-cost path to W. |
885 | * Calculate nexthop of to W from V. */ | |
bd34fb34 | 886 | ospf_nexthop_calculation (area, v, w, l, distance); |
718e3744 | 887 | } |
462f20d5 | 888 | /* less than. */ |
889 | else | |
718e3744 | 890 | { |
bc20c1a4 PJ |
891 | /* Found a lower-cost path to W. |
892 | * nexthop_calculation is conditional, if it finds | |
893 | * valid nexthop it will call spf_add_parents, which | |
894 | * will flush the old parents | |
895 | */ | |
bd34fb34 | 896 | if (ospf_nexthop_calculation (area, v, w, l, distance)) |
7591d8b8 PJ |
897 | /* Decrease the key of the node in the heap. |
898 | * trickle-sort it up towards root, just in case this | |
899 | * node should now be the new root due the cost change. | |
e95537f0 | 900 | * (next pqueu_{de,en}queue will fully re-heap the queue). |
7591d8b8 PJ |
901 | */ |
902 | trickle_up (w_lsa->stat, candidate); | |
718e3744 | 903 | } |
630e4807 | 904 | } /* end W is already on the candidate list */ |
905 | } /* end loop over the links in V's LSA */ | |
718e3744 | 906 | } |
907 | ||
4dadc291 | 908 | static void |
718e3744 | 909 | ospf_spf_dump (struct vertex *v, int i) |
910 | { | |
52dc7ee6 | 911 | struct listnode *cnode; |
912 | struct listnode *nnode; | |
eb3da6df | 913 | struct vertex_parent *parent; |
718e3744 | 914 | |
915 | if (v->type == OSPF_VERTEX_ROUTER) | |
916 | { | |
917 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 918 | zlog_debug ("SPF Result: %d [R] %s", i, inet_ntoa (v->lsa->id)); |
718e3744 | 919 | } |
920 | else | |
921 | { | |
922 | struct network_lsa *lsa = (struct network_lsa *) v->lsa; | |
923 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 924 | zlog_debug ("SPF Result: %d [N] %s/%d", i, inet_ntoa (v->lsa->id), |
0c0f9cd5 | 925 | ip_masklen (lsa->mask)); |
630e4807 | 926 | } |
718e3744 | 927 | |
1eb8ef25 | 928 | if (IS_DEBUG_OSPF_EVENT) |
eb3da6df | 929 | for (ALL_LIST_ELEMENTS_RO (v->parents, nnode, parent)) |
930 | { | |
931 | zlog_debug (" nexthop %p %s %s", | |
932 | parent->nexthop, | |
933 | inet_ntoa (parent->nexthop->router), | |
934 | parent->nexthop->oi ? IF_NAME(parent->nexthop->oi) | |
935 | : "NULL"); | |
936 | } | |
718e3744 | 937 | |
938 | i++; | |
939 | ||
eb3da6df | 940 | for (ALL_LIST_ELEMENTS_RO (v->children, cnode, v)) |
1eb8ef25 | 941 | ospf_spf_dump (v, i); |
718e3744 | 942 | } |
943 | ||
944 | /* Second stage of SPF calculation. */ | |
4dadc291 | 945 | static void |
0c0f9cd5 | 946 | ospf_spf_process_stubs (struct ospf_area *area, struct vertex *v, |
b3bc68e5 PJ |
947 | struct route_table *rt, |
948 | int parent_is_root) | |
718e3744 | 949 | { |
1eb8ef25 | 950 | struct listnode *cnode, *cnnode; |
718e3744 | 951 | struct vertex *child; |
952 | ||
953 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 954 | zlog_debug ("ospf_process_stub():processing stubs for area %s", |
0c0f9cd5 | 955 | inet_ntoa (area->area_id)); |
718e3744 | 956 | if (v->type == OSPF_VERTEX_ROUTER) |
957 | { | |
958 | u_char *p; | |
959 | u_char *lim; | |
960 | struct router_lsa_link *l; | |
961 | struct router_lsa *rlsa; | |
962 | ||
0c0f9cd5 | 963 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 964 | zlog_debug ("ospf_process_stubs():processing router LSA, id: %s", |
0c0f9cd5 | 965 | inet_ntoa (v->lsa->id)); |
718e3744 | 966 | rlsa = (struct router_lsa *) v->lsa; |
967 | ||
968 | ||
0c0f9cd5 | 969 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 970 | zlog_debug ("ospf_process_stubs(): we have %d links to process", |
0c0f9cd5 | 971 | ntohs (rlsa->links)); |
630e4807 | 972 | p = ((u_char *) v->lsa) + OSPF_LSA_HEADER_SIZE + 4; |
718e3744 | 973 | lim = ((u_char *) v->lsa) + ntohs (v->lsa->length); |
974 | ||
975 | while (p < lim) | |
976 | { | |
977 | l = (struct router_lsa_link *) p; | |
978 | ||
979 | p += (ROUTER_LSA_MIN_SIZE + | |
980 | (l->m[0].tos_count * ROUTER_LSA_TOS_SIZE)); | |
981 | ||
982 | if (l->m[0].type == LSA_LINK_TYPE_STUB) | |
b3bc68e5 | 983 | ospf_intra_add_stub (rt, l, v, area, parent_is_root); |
718e3744 | 984 | } |
985 | } | |
986 | ||
630e4807 | 987 | ospf_vertex_dump("ospf_process_stubs(): after examining links: ", v, 1, 1); |
718e3744 | 988 | |
eb3da6df | 989 | for (ALL_LIST_ELEMENTS (v->children, cnode, cnnode, child)) |
718e3744 | 990 | { |
718e3744 | 991 | if (CHECK_FLAG (child->flags, OSPF_VERTEX_PROCESSED)) |
0c0f9cd5 | 992 | continue; |
b3bc68e5 PJ |
993 | |
994 | /* the first level of routers connected to the root | |
995 | * should have 'parent_is_root' set, including those | |
996 | * connected via a network vertex. | |
997 | */ | |
998 | if (area->spf == v) | |
999 | parent_is_root = 1; | |
1000 | else if (v->type == OSPF_VERTEX_ROUTER) | |
1001 | parent_is_root = 0; | |
1002 | ||
1003 | ospf_spf_process_stubs (area, child, rt, parent_is_root); | |
718e3744 | 1004 | |
1005 | SET_FLAG (child->flags, OSPF_VERTEX_PROCESSED); | |
1006 | } | |
1007 | } | |
1008 | ||
1009 | void | |
1010 | ospf_rtrs_free (struct route_table *rtrs) | |
1011 | { | |
1012 | struct route_node *rn; | |
52dc7ee6 | 1013 | struct list *or_list; |
1eb8ef25 | 1014 | struct ospf_route *or; |
1015 | struct listnode *node, *nnode; | |
718e3744 | 1016 | |
1017 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1018 | zlog_debug ("Route: Router Routing Table free"); |
718e3744 | 1019 | |
1020 | for (rn = route_top (rtrs); rn; rn = route_next (rn)) | |
1021 | if ((or_list = rn->info) != NULL) | |
1022 | { | |
1eb8ef25 | 1023 | for (ALL_LIST_ELEMENTS (or_list, node, nnode, or)) |
1024 | ospf_route_free (or); | |
718e3744 | 1025 | |
0c0f9cd5 | 1026 | list_delete (or_list); |
718e3744 | 1027 | |
0c0f9cd5 | 1028 | /* Unlock the node. */ |
1029 | rn->info = NULL; | |
1030 | route_unlock_node (rn); | |
718e3744 | 1031 | } |
1032 | route_table_finish (rtrs); | |
1033 | } | |
1034 | ||
4dadc291 | 1035 | static void |
718e3744 | 1036 | ospf_rtrs_print (struct route_table *rtrs) |
1037 | { | |
1038 | struct route_node *rn; | |
52dc7ee6 | 1039 | struct list *or_list; |
1040 | struct listnode *ln; | |
1041 | struct listnode *pnode; | |
718e3744 | 1042 | struct ospf_route *or; |
1043 | struct ospf_path *path; | |
1044 | char buf1[BUFSIZ]; | |
1045 | char buf2[BUFSIZ]; | |
1046 | ||
1047 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1048 | zlog_debug ("ospf_rtrs_print() start"); |
718e3744 | 1049 | |
1050 | for (rn = route_top (rtrs); rn; rn = route_next (rn)) | |
1051 | if ((or_list = rn->info) != NULL) | |
1eb8ef25 | 1052 | for (ALL_LIST_ELEMENTS_RO (or_list, ln, or)) |
718e3744 | 1053 | { |
718e3744 | 1054 | switch (or->path_type) |
1055 | { | |
1056 | case OSPF_PATH_INTRA_AREA: | |
0c0f9cd5 | 1057 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 1058 | zlog_debug ("%s [%d] area: %s", |
0c0f9cd5 | 1059 | inet_ntop (AF_INET, &or->id, buf1, BUFSIZ), |
1060 | or->cost, inet_ntop (AF_INET, &or->u.std.area_id, | |
1061 | buf2, BUFSIZ)); | |
718e3744 | 1062 | break; |
1063 | case OSPF_PATH_INTER_AREA: | |
0c0f9cd5 | 1064 | if (IS_DEBUG_OSPF_EVENT) |
2a42e285 | 1065 | zlog_debug ("%s IA [%d] area: %s", |
0c0f9cd5 | 1066 | inet_ntop (AF_INET, &or->id, buf1, BUFSIZ), |
1067 | or->cost, inet_ntop (AF_INET, &or->u.std.area_id, | |
1068 | buf2, BUFSIZ)); | |
718e3744 | 1069 | break; |
1070 | default: | |
1071 | break; | |
1072 | } | |
1073 | ||
1eb8ef25 | 1074 | for (ALL_LIST_ELEMENTS_RO (or->paths, pnode, path)) |
718e3744 | 1075 | { |
718e3744 | 1076 | if (path->nexthop.s_addr == 0) |
0c0f9cd5 | 1077 | { |
1078 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1079 | zlog_debug (" directly attached to %s\r\n", |
0c0f9cd5 | 1080 | IF_NAME (path->oi)); |
1081 | } | |
1082 | else | |
1083 | { | |
1084 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1085 | zlog_debug (" via %s, %s\r\n", |
0c0f9cd5 | 1086 | inet_ntoa (path->nexthop), IF_NAME (path->oi)); |
1087 | } | |
718e3744 | 1088 | } |
1089 | } | |
1090 | ||
2a42e285 | 1091 | zlog_debug ("ospf_rtrs_print() end"); |
718e3744 | 1092 | } |
1093 | ||
1094 | /* Calculating the shortest-path tree for an area. */ | |
4dadc291 | 1095 | static void |
0c0f9cd5 | 1096 | ospf_spf_calculate (struct ospf_area *area, struct route_table *new_table, |
718e3744 | 1097 | struct route_table *new_rtrs) |
1098 | { | |
462f20d5 | 1099 | struct pqueue *candidate; |
718e3744 | 1100 | struct vertex *v; |
eb3da6df | 1101 | |
718e3744 | 1102 | if (IS_DEBUG_OSPF_EVENT) |
1103 | { | |
2a42e285 | 1104 | zlog_debug ("ospf_spf_calculate: Start"); |
1105 | zlog_debug ("ospf_spf_calculate: running Dijkstra for area %s", | |
0c0f9cd5 | 1106 | inet_ntoa (area->area_id)); |
718e3744 | 1107 | } |
1108 | ||
1109 | /* Check router-lsa-self. If self-router-lsa is not yet allocated, | |
1110 | return this area's calculation. */ | |
0c0f9cd5 | 1111 | if (!area->router_lsa_self) |
718e3744 | 1112 | { |
1113 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1114 | zlog_debug ("ospf_spf_calculate: " |
0c0f9cd5 | 1115 | "Skip area %s's calculation due to empty router_lsa_self", |
1116 | inet_ntoa (area->area_id)); | |
718e3744 | 1117 | return; |
1118 | } | |
1119 | ||
1120 | /* RFC2328 16.1. (1). */ | |
0c0f9cd5 | 1121 | /* Initialize the algorithm's data structures. */ |
462f20d5 | 1122 | |
1123 | /* This function scans all the LSA database and set the stat field to | |
1124 | * LSA_SPF_NOT_EXPLORED. */ | |
1125 | ospf_lsdb_clean_stat (area->lsdb); | |
1126 | /* Create a new heap for the candidates. */ | |
1127 | candidate = pqueue_create(); | |
1128 | candidate->cmp = cmp; | |
1129 | candidate->update = update_stat; | |
718e3744 | 1130 | |
1131 | /* Initialize the shortest-path tree to only the root (which is the | |
1132 | router doing the calculation). */ | |
1133 | ospf_spf_init (area); | |
1134 | v = area->spf; | |
462f20d5 | 1135 | /* Set LSA position to LSA_SPF_IN_SPFTREE. This vertex is the root of the |
1136 | * spanning tree. */ | |
1137 | *(v->stat) = LSA_SPF_IN_SPFTREE; | |
718e3744 | 1138 | |
1139 | /* Set Area A's TransitCapability to FALSE. */ | |
1140 | area->transit = OSPF_TRANSIT_FALSE; | |
1141 | area->shortcut_capability = 1; | |
eb3da6df | 1142 | |
718e3744 | 1143 | for (;;) |
1144 | { | |
1145 | /* RFC2328 16.1. (2). */ | |
462f20d5 | 1146 | ospf_spf_next (v, area, candidate); |
718e3744 | 1147 | |
1148 | /* RFC2328 16.1. (3). */ | |
1149 | /* If at this step the candidate list is empty, the shortest- | |
1150 | path tree (of transit vertices) has been completely built and | |
1151 | this stage of the procedure terminates. */ | |
462f20d5 | 1152 | if (candidate->size == 0) |
718e3744 | 1153 | break; |
1154 | ||
1155 | /* Otherwise, choose the vertex belonging to the candidate list | |
1156 | that is closest to the root, and add it to the shortest-path | |
1157 | tree (removing it from the candidate list in the | |
0c0f9cd5 | 1158 | process). */ |
462f20d5 | 1159 | /* Extract from the candidates the node with the lower key. */ |
1160 | v = (struct vertex *) pqueue_dequeue (candidate); | |
1161 | /* Update stat field in vertex. */ | |
1162 | *(v->stat) = LSA_SPF_IN_SPFTREE; | |
eb3da6df | 1163 | |
718e3744 | 1164 | ospf_vertex_add_parent (v); |
1165 | ||
718e3744 | 1166 | /* Note that when there is a choice of vertices closest to the |
1167 | root, network vertices must be chosen before router vertices | |
1168 | in order to necessarily find all equal-cost paths. */ | |
1169 | /* We don't do this at this moment, we should add the treatment | |
1170 | above codes. -- kunihiro. */ | |
1171 | ||
1172 | /* RFC2328 16.1. (4). */ | |
1173 | if (v->type == OSPF_VERTEX_ROUTER) | |
1174 | ospf_intra_add_router (new_rtrs, v, area); | |
0c0f9cd5 | 1175 | else |
718e3744 | 1176 | ospf_intra_add_transit (new_table, v, area); |
1177 | ||
1178 | /* RFC2328 16.1. (5). */ | |
1179 | /* Iterate the algorithm by returning to Step 2. */ | |
630e4807 | 1180 | |
1181 | } /* end loop until no more candidate vertices */ | |
718e3744 | 1182 | |
1183 | if (IS_DEBUG_OSPF_EVENT) | |
1184 | { | |
1185 | ospf_spf_dump (area->spf, 0); | |
1186 | ospf_route_table_dump (new_table); | |
1187 | } | |
1188 | ||
1189 | /* Second stage of SPF calculation procedure's */ | |
b3bc68e5 | 1190 | ospf_spf_process_stubs (area, area->spf, new_table, 0); |
718e3744 | 1191 | |
eb3da6df | 1192 | /* Free candidate queue. */ |
462f20d5 | 1193 | pqueue_delete (candidate); |
eb3da6df | 1194 | |
1195 | ospf_vertex_dump (__func__, area->spf, 0, 1); | |
1196 | /* Free nexthop information, canonical versions of which are attached | |
1197 | * the first level of router vertices attached to the root vertex, see | |
1198 | * ospf_nexthop_calculation. | |
1199 | */ | |
1200 | ospf_canonical_nexthops_free (area->spf); | |
1201 | ||
9c27ef9b PJ |
1202 | /* Free SPF vertices, but not the list. List has ospf_vertex_free |
1203 | * as deconstructor. | |
1204 | */ | |
1205 | list_delete_all_node (&vertex_list); | |
eb3da6df | 1206 | |
718e3744 | 1207 | /* Increment SPF Calculation Counter. */ |
1208 | area->spf_calculation++; | |
1209 | ||
2518efd1 | 1210 | quagga_gettime (QUAGGA_CLK_MONOTONIC, &area->ospf->ts_spf); |
718e3744 | 1211 | |
1212 | if (IS_DEBUG_OSPF_EVENT) | |
9c27ef9b PJ |
1213 | zlog_debug ("ospf_spf_calculate: Stop. %ld vertices", |
1214 | mtype_stats_alloc(MTYPE_OSPF_VERTEX)); | |
718e3744 | 1215 | } |
1216 | \f | |
1217 | /* Timer for SPF calculation. */ | |
4dadc291 | 1218 | static int |
68980084 | 1219 | ospf_spf_calculate_timer (struct thread *thread) |
718e3744 | 1220 | { |
68980084 | 1221 | struct ospf *ospf = THREAD_ARG (thread); |
718e3744 | 1222 | struct route_table *new_table, *new_rtrs; |
1eb8ef25 | 1223 | struct ospf_area *area; |
1224 | struct listnode *node, *nnode; | |
718e3744 | 1225 | |
1226 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1227 | zlog_debug ("SPF: Timer (SPF calculation expire)"); |
0c0f9cd5 | 1228 | |
718e3744 | 1229 | ospf->t_spf_calc = NULL; |
1230 | ||
1231 | /* Allocate new table tree. */ | |
1232 | new_table = route_table_init (); | |
0c0f9cd5 | 1233 | new_rtrs = route_table_init (); |
718e3744 | 1234 | |
68980084 | 1235 | ospf_vl_unapprove (ospf); |
718e3744 | 1236 | |
1237 | /* Calculate SPF for each area. */ | |
1eb8ef25 | 1238 | for (ALL_LIST_ELEMENTS (ospf->areas, node, nnode, area)) |
9c27ef9b PJ |
1239 | { |
1240 | /* Do backbone last, so as to first discover intra-area paths | |
1241 | * for any back-bone virtual-links | |
1242 | */ | |
1243 | if (ospf->backbone && ospf->backbone == area) | |
1244 | continue; | |
1245 | ||
1246 | ospf_spf_calculate (area, new_table, new_rtrs); | |
1247 | } | |
1248 | ||
1249 | /* SPF for backbone, if required */ | |
1250 | if (ospf->backbone) | |
1251 | ospf_spf_calculate (ospf->backbone, new_table, new_rtrs); | |
1252 | ||
68980084 | 1253 | ospf_vl_shut_unapproved (ospf); |
718e3744 | 1254 | |
68980084 | 1255 | ospf_ia_routing (ospf, new_table, new_rtrs); |
718e3744 | 1256 | |
1257 | ospf_prune_unreachable_networks (new_table); | |
1258 | ospf_prune_unreachable_routers (new_rtrs); | |
1259 | ||
1260 | /* AS-external-LSA calculation should not be performed here. */ | |
1261 | ||
1262 | /* If new Router Route is installed, | |
1263 | then schedule re-calculate External routes. */ | |
1264 | if (1) | |
68980084 | 1265 | ospf_ase_calculate_schedule (ospf); |
718e3744 | 1266 | |
68980084 | 1267 | ospf_ase_calculate_timer_add (ospf); |
718e3744 | 1268 | |
1269 | /* Update routing table. */ | |
68980084 | 1270 | ospf_route_install (ospf, new_table); |
718e3744 | 1271 | |
1272 | /* Update ABR/ASBR routing table */ | |
68980084 | 1273 | if (ospf->old_rtrs) |
718e3744 | 1274 | { |
1275 | /* old_rtrs's node holds linked list of ospf_route. --kunihiro. */ | |
68980084 | 1276 | /* ospf_route_delete (ospf->old_rtrs); */ |
1277 | ospf_rtrs_free (ospf->old_rtrs); | |
718e3744 | 1278 | } |
1279 | ||
68980084 | 1280 | ospf->old_rtrs = ospf->new_rtrs; |
1281 | ospf->new_rtrs = new_rtrs; | |
718e3744 | 1282 | |
0c0f9cd5 | 1283 | if (IS_OSPF_ABR (ospf)) |
68980084 | 1284 | ospf_abr_task (ospf); |
718e3744 | 1285 | |
1286 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1287 | zlog_debug ("SPF: calculation complete"); |
718e3744 | 1288 | |
1289 | return 0; | |
1290 | } | |
1291 | ||
1292 | /* Add schedule for SPF calculation. To avoid frequenst SPF calc, we | |
1293 | set timer for SPF calc. */ | |
1294 | void | |
68980084 | 1295 | ospf_spf_calculate_schedule (struct ospf *ospf) |
718e3744 | 1296 | { |
d24f6e2a | 1297 | unsigned long delay, elapsed, ht; |
1298 | struct timeval result; | |
718e3744 | 1299 | |
1300 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1301 | zlog_debug ("SPF: calculation timer scheduled"); |
718e3744 | 1302 | |
1303 | /* OSPF instance does not exist. */ | |
68980084 | 1304 | if (ospf == NULL) |
718e3744 | 1305 | return; |
d24f6e2a | 1306 | |
718e3744 | 1307 | /* SPF calculation timer is already scheduled. */ |
68980084 | 1308 | if (ospf->t_spf_calc) |
718e3744 | 1309 | { |
1310 | if (IS_DEBUG_OSPF_EVENT) | |
2a42e285 | 1311 | zlog_debug ("SPF: calculation timer is already scheduled: %p", |
0c0f9cd5 | 1312 | ospf->t_spf_calc); |
718e3744 | 1313 | return; |
1314 | } | |
d24f6e2a | 1315 | |
1316 | /* XXX Monotic timers: we only care about relative time here. */ | |
2518efd1 | 1317 | result = tv_sub (recent_relative_time (), ospf->ts_spf); |
d24f6e2a | 1318 | |
1319 | elapsed = (result.tv_sec * 1000) + (result.tv_usec / 1000); | |
1320 | ht = ospf->spf_holdtime * ospf->spf_hold_multiplier; | |
1321 | ||
1322 | if (ht > ospf->spf_max_holdtime) | |
1323 | ht = ospf->spf_max_holdtime; | |
1324 | ||
718e3744 | 1325 | /* Get SPF calculation delay time. */ |
d24f6e2a | 1326 | if (elapsed < ht) |
718e3744 | 1327 | { |
d24f6e2a | 1328 | /* Got an event within the hold time of last SPF. We need to |
1329 | * increase the hold_multiplier, if it's not already at/past | |
1330 | * maximum value, and wasn't already increased.. | |
1331 | */ | |
1332 | if (ht < ospf->spf_max_holdtime) | |
1333 | ospf->spf_hold_multiplier++; | |
1334 | ||
1335 | /* always honour the SPF initial delay */ | |
1336 | if ( (ht - elapsed) < ospf->spf_delay) | |
0c0f9cd5 | 1337 | delay = ospf->spf_delay; |
718e3744 | 1338 | else |
d24f6e2a | 1339 | delay = ht - elapsed; |
718e3744 | 1340 | } |
1341 | else | |
d24f6e2a | 1342 | { |
1343 | /* Event is past required hold-time of last SPF */ | |
1344 | delay = ospf->spf_delay; | |
1345 | ospf->spf_hold_multiplier = 1; | |
1346 | } | |
1347 | ||
718e3744 | 1348 | if (IS_DEBUG_OSPF_EVENT) |
d24f6e2a | 1349 | zlog_debug ("SPF: calculation timer delay = %ld", delay); |
1350 | ||
68980084 | 1351 | ospf->t_spf_calc = |
d24f6e2a | 1352 | thread_add_timer_msec (master, ospf_spf_calculate_timer, ospf, delay); |
718e3744 | 1353 | } |