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Merge pull request #1496 from donaldsharp/install_failure
[mirror_frr.git] / bgpd / bgp_attr.c
1 /* BGP attributes management routines.
2 * Copyright (C) 1996, 97, 98, 1999 Kunihiro Ishiguro
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 */
20
21 #include <zebra.h>
22
23 #include "linklist.h"
24 #include "prefix.h"
25 #include "memory.h"
26 #include "vector.h"
27 #include "stream.h"
28 #include "log.h"
29 #include "hash.h"
30 #include "jhash.h"
31 #include "queue.h"
32 #include "table.h"
33 #include "filter.h"
34 #include "command.h"
35
36 #include "bgpd/bgpd.h"
37 #include "bgpd/bgp_attr.h"
38 #include "bgpd/bgp_route.h"
39 #include "bgpd/bgp_aspath.h"
40 #include "bgpd/bgp_community.h"
41 #include "bgpd/bgp_debug.h"
42 #include "bgpd/bgp_label.h"
43 #include "bgpd/bgp_packet.h"
44 #include "bgpd/bgp_ecommunity.h"
45 #include "bgpd/bgp_lcommunity.h"
46 #include "bgpd/bgp_updgrp.h"
47 #include "bgpd/bgp_encap_types.h"
48 #if ENABLE_BGP_VNC
49 #include "bgpd/rfapi/bgp_rfapi_cfg.h"
50 #include "bgp_encap_types.h"
51 #include "bgp_vnc_types.h"
52 #endif
53 #include "bgp_encap_types.h"
54 #include "bgp_evpn.h"
55
56 /* Attribute strings for logging. */
57 static const struct message attr_str[] = {
58 {BGP_ATTR_ORIGIN, "ORIGIN"},
59 {BGP_ATTR_AS_PATH, "AS_PATH"},
60 {BGP_ATTR_NEXT_HOP, "NEXT_HOP"},
61 {BGP_ATTR_MULTI_EXIT_DISC, "MULTI_EXIT_DISC"},
62 {BGP_ATTR_LOCAL_PREF, "LOCAL_PREF"},
63 {BGP_ATTR_ATOMIC_AGGREGATE, "ATOMIC_AGGREGATE"},
64 {BGP_ATTR_AGGREGATOR, "AGGREGATOR"},
65 {BGP_ATTR_COMMUNITIES, "COMMUNITY"},
66 {BGP_ATTR_ORIGINATOR_ID, "ORIGINATOR_ID"},
67 {BGP_ATTR_CLUSTER_LIST, "CLUSTER_LIST"},
68 {BGP_ATTR_DPA, "DPA"},
69 {BGP_ATTR_ADVERTISER, "ADVERTISER"},
70 {BGP_ATTR_RCID_PATH, "RCID_PATH"},
71 {BGP_ATTR_MP_REACH_NLRI, "MP_REACH_NLRI"},
72 {BGP_ATTR_MP_UNREACH_NLRI, "MP_UNREACH_NLRI"},
73 {BGP_ATTR_EXT_COMMUNITIES, "EXT_COMMUNITIES"},
74 {BGP_ATTR_AS4_PATH, "AS4_PATH"},
75 {BGP_ATTR_AS4_AGGREGATOR, "AS4_AGGREGATOR"},
76 {BGP_ATTR_AS_PATHLIMIT, "AS_PATHLIMIT"},
77 {BGP_ATTR_ENCAP, "ENCAP"},
78 #if ENABLE_BGP_VNC
79 {BGP_ATTR_VNC, "VNC"},
80 #endif
81 {BGP_ATTR_LARGE_COMMUNITIES, "LARGE_COMMUNITY"},
82 {BGP_ATTR_PREFIX_SID, "PREFIX_SID"},
83 {0}};
84
85 static const struct message attr_flag_str[] =
86 {
87 {BGP_ATTR_FLAG_OPTIONAL, "Optional"},
88 {BGP_ATTR_FLAG_TRANS, "Transitive"},
89 {BGP_ATTR_FLAG_PARTIAL, "Partial"},
90 /* bgp_attr_flags_diagnose() relies on this bit being last in
91 this list */
92 {BGP_ATTR_FLAG_EXTLEN, "Extended Length"},
93 {0}};
94
95 static struct hash *cluster_hash;
96
97 static void *cluster_hash_alloc(void *p)
98 {
99 const struct cluster_list *val = (const struct cluster_list *)p;
100 struct cluster_list *cluster;
101
102 cluster = XMALLOC(MTYPE_CLUSTER, sizeof(struct cluster_list));
103 cluster->length = val->length;
104
105 if (cluster->length) {
106 cluster->list = XMALLOC(MTYPE_CLUSTER_VAL, val->length);
107 memcpy(cluster->list, val->list, val->length);
108 } else
109 cluster->list = NULL;
110
111 cluster->refcnt = 0;
112
113 return cluster;
114 }
115
116 /* Cluster list related functions. */
117 static struct cluster_list *cluster_parse(struct in_addr *pnt, int length)
118 {
119 struct cluster_list tmp;
120 struct cluster_list *cluster;
121
122 tmp.length = length;
123 tmp.list = pnt;
124
125 cluster = hash_get(cluster_hash, &tmp, cluster_hash_alloc);
126 cluster->refcnt++;
127 return cluster;
128 }
129
130 int cluster_loop_check(struct cluster_list *cluster, struct in_addr originator)
131 {
132 int i;
133
134 for (i = 0; i < cluster->length / 4; i++)
135 if (cluster->list[i].s_addr == originator.s_addr)
136 return 1;
137 return 0;
138 }
139
140 static unsigned int cluster_hash_key_make(void *p)
141 {
142 const struct cluster_list *cluster = p;
143
144 return jhash(cluster->list, cluster->length, 0);
145 }
146
147 static int cluster_hash_cmp(const void *p1, const void *p2)
148 {
149 const struct cluster_list *cluster1 = p1;
150 const struct cluster_list *cluster2 = p2;
151
152 return (cluster1->length == cluster2->length
153 && memcmp(cluster1->list, cluster2->list, cluster1->length)
154 == 0);
155 }
156
157 static void cluster_free(struct cluster_list *cluster)
158 {
159 if (cluster->list)
160 XFREE(MTYPE_CLUSTER_VAL, cluster->list);
161 XFREE(MTYPE_CLUSTER, cluster);
162 }
163
164 static struct cluster_list *cluster_intern(struct cluster_list *cluster)
165 {
166 struct cluster_list *find;
167
168 find = hash_get(cluster_hash, cluster, cluster_hash_alloc);
169 find->refcnt++;
170
171 return find;
172 }
173
174 void cluster_unintern(struct cluster_list *cluster)
175 {
176 if (cluster->refcnt)
177 cluster->refcnt--;
178
179 if (cluster->refcnt == 0) {
180 hash_release(cluster_hash, cluster);
181 cluster_free(cluster);
182 }
183 }
184
185 static void cluster_init(void)
186 {
187 cluster_hash = hash_create(cluster_hash_key_make,
188 cluster_hash_cmp,
189 "BGP Cluster");
190 }
191
192 static void cluster_finish(void)
193 {
194 hash_clean(cluster_hash, (void (*)(void *))cluster_free);
195 hash_free(cluster_hash);
196 cluster_hash = NULL;
197 }
198
199 static struct hash *encap_hash = NULL;
200 #if ENABLE_BGP_VNC
201 static struct hash *vnc_hash = NULL;
202 #endif
203
204 struct bgp_attr_encap_subtlv *encap_tlv_dup(struct bgp_attr_encap_subtlv *orig)
205 {
206 struct bgp_attr_encap_subtlv *new;
207 struct bgp_attr_encap_subtlv *tail;
208 struct bgp_attr_encap_subtlv *p;
209
210 for (p = orig, tail = new = NULL; p; p = p->next) {
211 int size = sizeof(struct bgp_attr_encap_subtlv) + p->length;
212 if (tail) {
213 tail->next = XCALLOC(MTYPE_ENCAP_TLV, size);
214 tail = tail->next;
215 } else {
216 tail = new = XCALLOC(MTYPE_ENCAP_TLV, size);
217 }
218 assert(tail);
219 memcpy(tail, p, size);
220 tail->next = NULL;
221 }
222
223 return new;
224 }
225
226 static void encap_free(struct bgp_attr_encap_subtlv *p)
227 {
228 struct bgp_attr_encap_subtlv *next;
229 while (p) {
230 next = p->next;
231 p->next = NULL;
232 XFREE(MTYPE_ENCAP_TLV, p);
233 p = next;
234 }
235 }
236
237 void bgp_attr_flush_encap(struct attr *attr)
238 {
239 if (!attr)
240 return;
241
242 if (attr->encap_subtlvs) {
243 encap_free(attr->encap_subtlvs);
244 attr->encap_subtlvs = NULL;
245 }
246 #if ENABLE_BGP_VNC
247 if (attr->vnc_subtlvs) {
248 encap_free(attr->vnc_subtlvs);
249 attr->vnc_subtlvs = NULL;
250 }
251 #endif
252 }
253
254 /*
255 * Compare encap sub-tlv chains
256 *
257 * 1 = equivalent
258 * 0 = not equivalent
259 *
260 * This algorithm could be made faster if needed
261 */
262 static int encap_same(struct bgp_attr_encap_subtlv *h1,
263 struct bgp_attr_encap_subtlv *h2)
264 {
265 struct bgp_attr_encap_subtlv *p;
266 struct bgp_attr_encap_subtlv *q;
267
268 if (h1 == h2)
269 return 1;
270 if (h1 == NULL || h2 == NULL)
271 return 0;
272
273 for (p = h1; p; p = p->next) {
274 for (q = h2; q; q = q->next) {
275 if ((p->type == q->type) && (p->length == q->length)
276 && !memcmp(p->value, q->value, p->length)) {
277
278 break;
279 }
280 }
281 if (!q)
282 return 0;
283 }
284
285 for (p = h2; p; p = p->next) {
286 for (q = h1; q; q = q->next) {
287 if ((p->type == q->type) && (p->length == q->length)
288 && !memcmp(p->value, q->value, p->length)) {
289
290 break;
291 }
292 }
293 if (!q)
294 return 0;
295 }
296
297 return 1;
298 }
299
300 static void *encap_hash_alloc(void *p)
301 {
302 /* Encap structure is already allocated. */
303 return p;
304 }
305
306 typedef enum {
307 ENCAP_SUBTLV_TYPE,
308 #if ENABLE_BGP_VNC
309 VNC_SUBTLV_TYPE
310 #endif
311 } encap_subtlv_type;
312
313 static struct bgp_attr_encap_subtlv *
314 encap_intern(struct bgp_attr_encap_subtlv *encap, encap_subtlv_type type)
315 {
316 struct bgp_attr_encap_subtlv *find;
317 struct hash *hash = encap_hash;
318 #if ENABLE_BGP_VNC
319 if (type == VNC_SUBTLV_TYPE)
320 hash = vnc_hash;
321 #endif
322
323 find = hash_get(hash, encap, encap_hash_alloc);
324 if (find != encap)
325 encap_free(encap);
326 find->refcnt++;
327
328 return find;
329 }
330
331 static void encap_unintern(struct bgp_attr_encap_subtlv **encapp,
332 encap_subtlv_type type)
333 {
334 struct bgp_attr_encap_subtlv *encap = *encapp;
335 if (encap->refcnt)
336 encap->refcnt--;
337
338 if (encap->refcnt == 0) {
339 struct hash *hash = encap_hash;
340 #if ENABLE_BGP_VNC
341 if (type == VNC_SUBTLV_TYPE)
342 hash = vnc_hash;
343 #endif
344 hash_release(hash, encap);
345 encap_free(encap);
346 *encapp = NULL;
347 }
348 }
349
350 static unsigned int encap_hash_key_make(void *p)
351 {
352 const struct bgp_attr_encap_subtlv *encap = p;
353
354 return jhash(encap->value, encap->length, 0);
355 }
356
357 static int encap_hash_cmp(const void *p1, const void *p2)
358 {
359 return encap_same((struct bgp_attr_encap_subtlv *)p1,
360 (struct bgp_attr_encap_subtlv *)p2);
361 }
362
363 static void encap_init(void)
364 {
365 encap_hash = hash_create(encap_hash_key_make,
366 encap_hash_cmp,
367 "BGP Encap Hash");
368 #if ENABLE_BGP_VNC
369 vnc_hash = hash_create(encap_hash_key_make,
370 encap_hash_cmp,
371 "BGP VNC Hash");
372 #endif
373 }
374
375 static void encap_finish(void)
376 {
377 hash_clean(encap_hash, (void (*)(void *))encap_free);
378 hash_free(encap_hash);
379 encap_hash = NULL;
380 #if ENABLE_BGP_VNC
381 hash_clean(vnc_hash, (void (*)(void *))encap_free);
382 hash_free(vnc_hash);
383 vnc_hash = NULL;
384 #endif
385 }
386
387 static bool overlay_index_same(const struct attr *a1, const struct attr *a2)
388 {
389 if (!a1 && a2)
390 return false;
391 if (!a2 && a1)
392 return false;
393 if (!a1 && !a2)
394 return true;
395 return !memcmp(&(a1->evpn_overlay), &(a2->evpn_overlay),
396 sizeof(struct overlay_index));
397 }
398
399 /* Unknown transit attribute. */
400 static struct hash *transit_hash;
401
402 static void transit_free(struct transit *transit)
403 {
404 if (transit->val)
405 XFREE(MTYPE_TRANSIT_VAL, transit->val);
406 XFREE(MTYPE_TRANSIT, transit);
407 }
408
409 static void *transit_hash_alloc(void *p)
410 {
411 /* Transit structure is already allocated. */
412 return p;
413 }
414
415 static struct transit *transit_intern(struct transit *transit)
416 {
417 struct transit *find;
418
419 find = hash_get(transit_hash, transit, transit_hash_alloc);
420 if (find != transit)
421 transit_free(transit);
422 find->refcnt++;
423
424 return find;
425 }
426
427 void transit_unintern(struct transit *transit)
428 {
429 if (transit->refcnt)
430 transit->refcnt--;
431
432 if (transit->refcnt == 0) {
433 hash_release(transit_hash, transit);
434 transit_free(transit);
435 }
436 }
437
438 static unsigned int transit_hash_key_make(void *p)
439 {
440 const struct transit *transit = p;
441
442 return jhash(transit->val, transit->length, 0);
443 }
444
445 static int transit_hash_cmp(const void *p1, const void *p2)
446 {
447 const struct transit *transit1 = p1;
448 const struct transit *transit2 = p2;
449
450 return (transit1->length == transit2->length
451 && memcmp(transit1->val, transit2->val, transit1->length) == 0);
452 }
453
454 static void transit_init(void)
455 {
456 transit_hash = hash_create(transit_hash_key_make,
457 transit_hash_cmp,
458 "BGP Transit Hash");
459 }
460
461 static void transit_finish(void)
462 {
463 hash_clean(transit_hash, (void (*)(void *))transit_free);
464 hash_free(transit_hash);
465 transit_hash = NULL;
466 }
467
468 /* Attribute hash routines. */
469 static struct hash *attrhash;
470
471 /* Shallow copy of an attribute
472 * Though, not so shallow that it doesn't copy the contents
473 * of the attr_extra pointed to by 'extra'
474 */
475 void bgp_attr_dup(struct attr *new, struct attr *orig)
476 {
477 *new = *orig;
478 }
479
480 unsigned long int attr_count(void)
481 {
482 return attrhash->count;
483 }
484
485 unsigned long int attr_unknown_count(void)
486 {
487 return transit_hash->count;
488 }
489
490 unsigned int attrhash_key_make(void *p)
491 {
492 const struct attr *attr = (struct attr *)p;
493 uint32_t key = 0;
494 #define MIX(val) key = jhash_1word(val, key)
495
496 MIX(attr->origin);
497 MIX(attr->nexthop.s_addr);
498 MIX(attr->med);
499 MIX(attr->local_pref);
500 MIX(attr->aggregator_as);
501 MIX(attr->aggregator_addr.s_addr);
502 MIX(attr->weight);
503 MIX(attr->mp_nexthop_global_in.s_addr);
504 MIX(attr->originator_id.s_addr);
505 MIX(attr->tag);
506 MIX(attr->label);
507 MIX(attr->label_index);
508
509 if (attr->aspath)
510 MIX(aspath_key_make(attr->aspath));
511 if (attr->community)
512 MIX(community_hash_make(attr->community));
513
514 if (attr->lcommunity)
515 MIX(lcommunity_hash_make(attr->lcommunity));
516 if (attr->ecommunity)
517 MIX(ecommunity_hash_make(attr->ecommunity));
518 if (attr->cluster)
519 MIX(cluster_hash_key_make(attr->cluster));
520 if (attr->transit)
521 MIX(transit_hash_key_make(attr->transit));
522 if (attr->encap_subtlvs)
523 MIX(encap_hash_key_make(attr->encap_subtlvs));
524 #if ENABLE_BGP_VNC
525 if (attr->vnc_subtlvs)
526 MIX(encap_hash_key_make(attr->vnc_subtlvs));
527 #endif
528 MIX(attr->mp_nexthop_len);
529 key = jhash(attr->mp_nexthop_global.s6_addr, IPV6_MAX_BYTELEN, key);
530 key = jhash(attr->mp_nexthop_local.s6_addr, IPV6_MAX_BYTELEN, key);
531
532 return key;
533 }
534
535 int attrhash_cmp(const void *p1, const void *p2)
536 {
537 const struct attr *attr1 = p1;
538 const struct attr *attr2 = p2;
539
540 if (attr1->flag == attr2->flag && attr1->origin == attr2->origin
541 && attr1->nexthop.s_addr == attr2->nexthop.s_addr
542 && attr1->aspath == attr2->aspath
543 && attr1->community == attr2->community && attr1->med == attr2->med
544 && attr1->local_pref == attr2->local_pref
545 && attr1->rmap_change_flags == attr2->rmap_change_flags) {
546 if (attr1->aggregator_as == attr2->aggregator_as
547 && attr1->aggregator_addr.s_addr
548 == attr2->aggregator_addr.s_addr
549 && attr1->weight == attr2->weight
550 && attr1->tag == attr2->tag
551 && attr1->label_index == attr2->label_index
552 && attr1->mp_nexthop_len == attr2->mp_nexthop_len
553 && IPV6_ADDR_SAME(&attr1->mp_nexthop_global,
554 &attr2->mp_nexthop_global)
555 && IPV6_ADDR_SAME(&attr1->mp_nexthop_local,
556 &attr2->mp_nexthop_local)
557 && IPV4_ADDR_SAME(&attr1->mp_nexthop_global_in,
558 &attr2->mp_nexthop_global_in)
559 && attr1->ecommunity == attr2->ecommunity
560 && attr1->lcommunity == attr2->lcommunity
561 && attr1->cluster == attr2->cluster
562 && attr1->transit == attr2->transit
563 && (attr1->encap_tunneltype == attr2->encap_tunneltype)
564 && encap_same(attr1->encap_subtlvs, attr2->encap_subtlvs)
565 #if ENABLE_BGP_VNC
566 && encap_same(attr1->vnc_subtlvs, attr2->vnc_subtlvs)
567 #endif
568 && IPV4_ADDR_SAME(&attr1->originator_id,
569 &attr2->originator_id)
570 && overlay_index_same(attr1, attr2))
571 return 1;
572 }
573
574 return 0;
575 }
576
577 static void attrhash_init(void)
578 {
579 attrhash = hash_create(attrhash_key_make,
580 attrhash_cmp,
581 "BGP Attributes");
582 }
583
584 /*
585 * special for hash_clean below
586 */
587 static void attr_vfree(void *attr)
588 {
589 XFREE(MTYPE_ATTR, attr);
590 }
591
592 static void attrhash_finish(void)
593 {
594 hash_clean(attrhash, attr_vfree);
595 hash_free(attrhash);
596 attrhash = NULL;
597 }
598
599 static void attr_show_all_iterator(struct hash_backet *backet, struct vty *vty)
600 {
601 struct attr *attr = backet->data;
602
603 vty_out(vty, "attr[%ld] nexthop %s\n", attr->refcnt,
604 inet_ntoa(attr->nexthop));
605 }
606
607 void attr_show_all(struct vty *vty)
608 {
609 hash_iterate(attrhash, (void (*)(struct hash_backet *,
610 void *))attr_show_all_iterator,
611 vty);
612 }
613
614 static void *bgp_attr_hash_alloc(void *p)
615 {
616 struct attr *val = (struct attr *)p;
617 struct attr *attr;
618
619 attr = XMALLOC(MTYPE_ATTR, sizeof(struct attr));
620 *attr = *val;
621 if (val->encap_subtlvs) {
622 val->encap_subtlvs = NULL;
623 }
624 #if ENABLE_BGP_VNC
625 if (val->vnc_subtlvs) {
626 val->vnc_subtlvs = NULL;
627 }
628 #endif
629 attr->refcnt = 0;
630 return attr;
631 }
632
633 /* Internet argument attribute. */
634 struct attr *bgp_attr_intern(struct attr *attr)
635 {
636 struct attr *find;
637
638 /* Intern referenced strucutre. */
639 if (attr->aspath) {
640 if (!attr->aspath->refcnt)
641 attr->aspath = aspath_intern(attr->aspath);
642 else
643 attr->aspath->refcnt++;
644 }
645 if (attr->community) {
646 if (!attr->community->refcnt)
647 attr->community = community_intern(attr->community);
648 else
649 attr->community->refcnt++;
650 }
651
652 if (attr->ecommunity) {
653 if (!attr->ecommunity->refcnt)
654 attr->ecommunity = ecommunity_intern(attr->ecommunity);
655 else
656 attr->ecommunity->refcnt++;
657 }
658 if (attr->lcommunity) {
659 if (!attr->lcommunity->refcnt)
660 attr->lcommunity = lcommunity_intern(attr->lcommunity);
661 else
662 attr->lcommunity->refcnt++;
663 }
664 if (attr->cluster) {
665 if (!attr->cluster->refcnt)
666 attr->cluster = cluster_intern(attr->cluster);
667 else
668 attr->cluster->refcnt++;
669 }
670 if (attr->transit) {
671 if (!attr->transit->refcnt)
672 attr->transit = transit_intern(attr->transit);
673 else
674 attr->transit->refcnt++;
675 }
676 if (attr->encap_subtlvs) {
677 if (!attr->encap_subtlvs->refcnt)
678 attr->encap_subtlvs = encap_intern(attr->encap_subtlvs,
679 ENCAP_SUBTLV_TYPE);
680 else
681 attr->encap_subtlvs->refcnt++;
682 }
683 #if ENABLE_BGP_VNC
684 if (attr->vnc_subtlvs) {
685 if (!attr->vnc_subtlvs->refcnt)
686 attr->vnc_subtlvs = encap_intern(attr->vnc_subtlvs,
687 VNC_SUBTLV_TYPE);
688 else
689 attr->vnc_subtlvs->refcnt++;
690 }
691 #endif
692
693 /* At this point, attr only contains intern'd pointers. that means
694 * if we find it in attrhash, it has all the same pointers and we
695 * correctly updated the refcounts on these.
696 * If we don't find it, we need to allocate a one because in all
697 * cases this returns a new reference to a hashed attr, but the input
698 * wasn't on hash. */
699 find = (struct attr *)hash_get(attrhash, attr, bgp_attr_hash_alloc);
700 find->refcnt++;
701
702 return find;
703 }
704
705 /* Make network statement's attribute. */
706 struct attr *bgp_attr_default_set(struct attr *attr, u_char origin)
707 {
708 memset(attr, 0, sizeof(struct attr));
709
710 attr->origin = origin;
711 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_ORIGIN);
712 attr->aspath = aspath_empty();
713 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_AS_PATH);
714 attr->weight = BGP_ATTR_DEFAULT_WEIGHT;
715 attr->tag = 0;
716 attr->label_index = BGP_INVALID_LABEL_INDEX;
717 attr->label = MPLS_INVALID_LABEL;
718 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_NEXT_HOP);
719 attr->mp_nexthop_len = IPV6_MAX_BYTELEN;
720
721 return attr;
722 }
723
724 /* Create the attributes for an aggregate */
725 struct attr *bgp_attr_aggregate_intern(struct bgp *bgp, u_char origin,
726 struct aspath *aspath,
727 struct community *community, int as_set,
728 u_char atomic_aggregate)
729 {
730 struct attr attr;
731 struct attr *new;
732
733 memset(&attr, 0, sizeof(struct attr));
734
735 /* Origin attribute. */
736 attr.origin = origin;
737 attr.flag |= ATTR_FLAG_BIT(BGP_ATTR_ORIGIN);
738
739 /* AS path attribute. */
740 if (aspath)
741 attr.aspath = aspath_intern(aspath);
742 else
743 attr.aspath = aspath_empty();
744 attr.flag |= ATTR_FLAG_BIT(BGP_ATTR_AS_PATH);
745
746 /* Next hop attribute. */
747 attr.flag |= ATTR_FLAG_BIT(BGP_ATTR_NEXT_HOP);
748
749 if (community) {
750 u_int32_t gshut = COMMUNITY_GSHUT;
751
752 /* If we are not shutting down ourselves and we are
753 * aggregating a route that contains the GSHUT community we
754 * need to remove that community when creating the aggregate */
755 if (!bgp_flag_check(bgp, BGP_FLAG_GRACEFUL_SHUTDOWN) &&
756 community_include(community, gshut)) {
757 community_del_val(community, &gshut);
758 }
759
760 attr.community = community;
761 attr.flag |= ATTR_FLAG_BIT(BGP_ATTR_COMMUNITIES);
762 }
763
764 if (bgp_flag_check(bgp, BGP_FLAG_GRACEFUL_SHUTDOWN)) {
765 bgp_attr_add_gshut_community(&attr);
766 }
767
768 attr.label_index = BGP_INVALID_LABEL_INDEX;
769 attr.label = MPLS_INVALID_LABEL;
770 attr.weight = BGP_ATTR_DEFAULT_WEIGHT;
771 attr.mp_nexthop_len = IPV6_MAX_BYTELEN;
772 if (!as_set || atomic_aggregate)
773 attr.flag |= ATTR_FLAG_BIT(BGP_ATTR_ATOMIC_AGGREGATE);
774 attr.flag |= ATTR_FLAG_BIT(BGP_ATTR_AGGREGATOR);
775 if (CHECK_FLAG(bgp->config, BGP_CONFIG_CONFEDERATION))
776 attr.aggregator_as = bgp->confed_id;
777 else
778 attr.aggregator_as = bgp->as;
779 attr.aggregator_addr = bgp->router_id;
780 attr.label_index = BGP_INVALID_LABEL_INDEX;
781 attr.label = MPLS_INVALID_LABEL;
782
783 new = bgp_attr_intern(&attr);
784
785 aspath_unintern(&new->aspath);
786 return new;
787 }
788
789 /* Unintern just the sub-components of the attr, but not the attr */
790 void bgp_attr_unintern_sub(struct attr *attr)
791 {
792 /* aspath refcount shoud be decrement. */
793 if (attr->aspath)
794 aspath_unintern(&attr->aspath);
795 UNSET_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_AS_PATH));
796
797 if (attr->community)
798 community_unintern(&attr->community);
799 UNSET_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_COMMUNITIES));
800
801 if (attr->ecommunity)
802 ecommunity_unintern(&attr->ecommunity);
803 UNSET_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_EXT_COMMUNITIES));
804
805 if (attr->lcommunity)
806 lcommunity_unintern(&attr->lcommunity);
807 UNSET_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_LARGE_COMMUNITIES));
808
809 if (attr->cluster)
810 cluster_unintern(attr->cluster);
811 UNSET_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_CLUSTER_LIST));
812
813 if (attr->transit)
814 transit_unintern(attr->transit);
815
816 if (attr->encap_subtlvs)
817 encap_unintern(&attr->encap_subtlvs, ENCAP_SUBTLV_TYPE);
818
819 #if ENABLE_BGP_VNC
820 if (attr->vnc_subtlvs)
821 encap_unintern(&attr->vnc_subtlvs, VNC_SUBTLV_TYPE);
822 #endif
823 }
824
825 /*
826 * We have some show commands that let you experimentally
827 * apply a route-map. When we apply the route-map
828 * we are reseting values but not saving them for
829 * posterity via intern'ing( because route-maps don't
830 * do that) but at this point in time we need
831 * to compare the new attr to the old and if the
832 * routemap has changed it we need to, as Snoop Dog says,
833 * Drop it like it's hot
834 */
835 void bgp_attr_undup(struct attr *new, struct attr *old)
836 {
837 if (new->aspath != old->aspath)
838 aspath_free(new->aspath);
839
840 if (new->community != old->community)
841 community_free(new->community);
842
843 if (new->ecommunity != old->ecommunity)
844 ecommunity_free(&new->ecommunity);
845
846 if (new->lcommunity != old->lcommunity)
847 lcommunity_free(&new->lcommunity);
848
849 }
850
851 /* Free bgp attribute and aspath. */
852 void bgp_attr_unintern(struct attr **pattr)
853 {
854 struct attr *attr = *pattr;
855 struct attr *ret;
856 struct attr tmp;
857
858 /* Decrement attribute reference. */
859 attr->refcnt--;
860
861 tmp = *attr;
862
863 /* If reference becomes zero then free attribute object. */
864 if (attr->refcnt == 0) {
865 ret = hash_release(attrhash, attr);
866 assert(ret != NULL);
867 XFREE(MTYPE_ATTR, attr);
868 *pattr = NULL;
869 }
870
871 bgp_attr_unintern_sub(&tmp);
872 }
873
874 void bgp_attr_flush(struct attr *attr)
875 {
876 if (attr->aspath && !attr->aspath->refcnt) {
877 aspath_free(attr->aspath);
878 attr->aspath = NULL;
879 }
880 if (attr->community && !attr->community->refcnt) {
881 community_free(attr->community);
882 attr->community = NULL;
883 }
884
885 if (attr->ecommunity && !attr->ecommunity->refcnt)
886 ecommunity_free(&attr->ecommunity);
887 if (attr->lcommunity && !attr->lcommunity->refcnt)
888 lcommunity_free(&attr->lcommunity);
889 if (attr->cluster && !attr->cluster->refcnt) {
890 cluster_free(attr->cluster);
891 attr->cluster = NULL;
892 }
893 if (attr->transit && !attr->transit->refcnt) {
894 transit_free(attr->transit);
895 attr->transit = NULL;
896 }
897 if (attr->encap_subtlvs && !attr->encap_subtlvs->refcnt) {
898 encap_free(attr->encap_subtlvs);
899 attr->encap_subtlvs = NULL;
900 }
901 #if ENABLE_BGP_VNC
902 if (attr->vnc_subtlvs && !attr->vnc_subtlvs->refcnt) {
903 encap_free(attr->vnc_subtlvs);
904 attr->vnc_subtlvs = NULL;
905 }
906 #endif
907 }
908
909 /* Implement draft-scudder-idr-optional-transitive behaviour and
910 * avoid resetting sessions for malformed attributes which are
911 * are partial/optional and hence where the error likely was not
912 * introduced by the sending neighbour.
913 */
914 static bgp_attr_parse_ret_t
915 bgp_attr_malformed(struct bgp_attr_parser_args *args, u_char subcode,
916 bgp_size_t length)
917 {
918 struct peer *const peer = args->peer;
919 const u_int8_t flags = args->flags;
920 /* startp and length must be special-cased, as whether or not to
921 * send the attribute data with the NOTIFY depends on the error,
922 * the caller therefore signals this with the seperate length argument
923 */
924 u_char *notify_datap = (length > 0 ? args->startp : NULL);
925
926 /* Only relax error handling for eBGP peers */
927 if (peer->sort != BGP_PEER_EBGP) {
928 bgp_notify_send_with_data(peer, BGP_NOTIFY_UPDATE_ERR, subcode,
929 notify_datap, length);
930 return BGP_ATTR_PARSE_ERROR;
931 }
932
933 /* Adjust the stream getp to the end of the attribute, in case we can
934 * still proceed but the caller hasn't read all the attribute.
935 */
936 stream_set_getp(BGP_INPUT(peer),
937 (args->startp - STREAM_DATA(BGP_INPUT(peer)))
938 + args->total);
939
940 switch (args->type) {
941 /* where an attribute is relatively inconsequential, e.g. it does not
942 * affect route selection, and can be safely ignored, then any such
943 * attributes which are malformed should just be ignored and the route
944 * processed as normal.
945 */
946 case BGP_ATTR_AS4_AGGREGATOR:
947 case BGP_ATTR_AGGREGATOR:
948 case BGP_ATTR_ATOMIC_AGGREGATE:
949 return BGP_ATTR_PARSE_PROCEED;
950
951 /* Core attributes, particularly ones which may influence route
952 * selection, should always cause session resets
953 */
954 case BGP_ATTR_ORIGIN:
955 case BGP_ATTR_AS_PATH:
956 case BGP_ATTR_NEXT_HOP:
957 case BGP_ATTR_MULTI_EXIT_DISC:
958 case BGP_ATTR_LOCAL_PREF:
959 case BGP_ATTR_COMMUNITIES:
960 case BGP_ATTR_ORIGINATOR_ID:
961 case BGP_ATTR_CLUSTER_LIST:
962 case BGP_ATTR_MP_REACH_NLRI:
963 case BGP_ATTR_MP_UNREACH_NLRI:
964 case BGP_ATTR_EXT_COMMUNITIES:
965 bgp_notify_send_with_data(peer, BGP_NOTIFY_UPDATE_ERR, subcode,
966 notify_datap, length);
967 return BGP_ATTR_PARSE_ERROR;
968 }
969
970 /* Partial optional attributes that are malformed should not cause
971 * the whole session to be reset. Instead treat it as a withdrawal
972 * of the routes, if possible.
973 */
974 if (CHECK_FLAG(flags, BGP_ATTR_FLAG_TRANS)
975 && CHECK_FLAG(flags, BGP_ATTR_FLAG_OPTIONAL)
976 && CHECK_FLAG(flags, BGP_ATTR_FLAG_PARTIAL))
977 return BGP_ATTR_PARSE_WITHDRAW;
978
979 /* default to reset */
980 return BGP_ATTR_PARSE_ERROR_NOTIFYPLS;
981 }
982
983 /* Find out what is wrong with the path attribute flag bits and log the error.
984 "Flag bits" here stand for Optional, Transitive and Partial, but not for
985 Extended Length. Checking O/T/P bits at once implies, that the attribute
986 being diagnosed is defined by RFC as either a "well-known" or an "optional,
987 non-transitive" attribute. */
988 static void
989 bgp_attr_flags_diagnose(struct bgp_attr_parser_args *args,
990 u_int8_t desired_flags /* how RFC says it must be */
991 )
992 {
993 u_char seen = 0, i;
994 u_char real_flags = args->flags;
995 const u_int8_t attr_code = args->type;
996
997 desired_flags &= ~BGP_ATTR_FLAG_EXTLEN;
998 real_flags &= ~BGP_ATTR_FLAG_EXTLEN;
999 for (i = 0; i <= 2; i++) /* O,T,P, but not E */
1000 if (CHECK_FLAG(desired_flags, attr_flag_str[i].key)
1001 != CHECK_FLAG(real_flags, attr_flag_str[i].key)) {
1002 zlog_err("%s attribute must%s be flagged as \"%s\"",
1003 lookup_msg(attr_str, attr_code, NULL),
1004 CHECK_FLAG(desired_flags, attr_flag_str[i].key)
1005 ? ""
1006 : " not",
1007 attr_flag_str[i].str);
1008 seen = 1;
1009 }
1010 if (!seen) {
1011 zlog_debug(
1012 "Strange, %s called for attr %s, but no problem found with flags"
1013 " (real flags 0x%x, desired 0x%x)",
1014 __func__, lookup_msg(attr_str, attr_code, NULL),
1015 real_flags, desired_flags);
1016 }
1017 }
1018
1019 /* Required flags for attributes. EXTLEN will be masked off when testing,
1020 * as will PARTIAL for optional+transitive attributes.
1021 */
1022 const u_int8_t attr_flags_values[] = {
1023 [BGP_ATTR_ORIGIN] = BGP_ATTR_FLAG_TRANS,
1024 [BGP_ATTR_AS_PATH] = BGP_ATTR_FLAG_TRANS,
1025 [BGP_ATTR_NEXT_HOP] = BGP_ATTR_FLAG_TRANS,
1026 [BGP_ATTR_MULTI_EXIT_DISC] = BGP_ATTR_FLAG_OPTIONAL,
1027 [BGP_ATTR_LOCAL_PREF] = BGP_ATTR_FLAG_TRANS,
1028 [BGP_ATTR_ATOMIC_AGGREGATE] = BGP_ATTR_FLAG_TRANS,
1029 [BGP_ATTR_AGGREGATOR] =
1030 BGP_ATTR_FLAG_TRANS | BGP_ATTR_FLAG_OPTIONAL,
1031 [BGP_ATTR_COMMUNITIES] =
1032 BGP_ATTR_FLAG_TRANS | BGP_ATTR_FLAG_OPTIONAL,
1033 [BGP_ATTR_ORIGINATOR_ID] = BGP_ATTR_FLAG_OPTIONAL,
1034 [BGP_ATTR_CLUSTER_LIST] = BGP_ATTR_FLAG_OPTIONAL,
1035 [BGP_ATTR_MP_REACH_NLRI] = BGP_ATTR_FLAG_OPTIONAL,
1036 [BGP_ATTR_MP_UNREACH_NLRI] = BGP_ATTR_FLAG_OPTIONAL,
1037 [BGP_ATTR_EXT_COMMUNITIES] =
1038 BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS,
1039 [BGP_ATTR_AS4_PATH] =
1040 BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS,
1041 [BGP_ATTR_AS4_AGGREGATOR] =
1042 BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS,
1043 [BGP_ATTR_LARGE_COMMUNITIES] =
1044 BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS,
1045 [BGP_ATTR_PREFIX_SID] =
1046 BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS,
1047 };
1048 static const size_t attr_flags_values_max = array_size(attr_flags_values) - 1;
1049
1050 static int bgp_attr_flag_invalid(struct bgp_attr_parser_args *args)
1051 {
1052 u_int8_t mask = BGP_ATTR_FLAG_EXTLEN;
1053 const u_int8_t flags = args->flags;
1054 const u_int8_t attr_code = args->type;
1055
1056 /* there may be attributes we don't know about */
1057 if (attr_code > attr_flags_values_max)
1058 return 0;
1059 if (attr_flags_values[attr_code] == 0)
1060 return 0;
1061
1062 /* RFC4271, "For well-known attributes, the Transitive bit MUST be set
1063 * to
1064 * 1."
1065 */
1066 if (!CHECK_FLAG(BGP_ATTR_FLAG_OPTIONAL, flags)
1067 && !CHECK_FLAG(BGP_ATTR_FLAG_TRANS, flags)) {
1068 zlog_err(
1069 "%s well-known attributes must have transitive flag set (%x)",
1070 lookup_msg(attr_str, attr_code, NULL), flags);
1071 return 1;
1072 }
1073
1074 /* "For well-known attributes and for optional non-transitive
1075 * attributes,
1076 * the Partial bit MUST be set to 0."
1077 */
1078 if (CHECK_FLAG(flags, BGP_ATTR_FLAG_PARTIAL)) {
1079 if (!CHECK_FLAG(flags, BGP_ATTR_FLAG_OPTIONAL)) {
1080 zlog_err(
1081 "%s well-known attribute "
1082 "must NOT have the partial flag set (%x)",
1083 lookup_msg(attr_str, attr_code, NULL), flags);
1084 return 1;
1085 }
1086 if (CHECK_FLAG(flags, BGP_ATTR_FLAG_OPTIONAL)
1087 && !CHECK_FLAG(flags, BGP_ATTR_FLAG_TRANS)) {
1088 zlog_err(
1089 "%s optional + transitive attribute "
1090 "must NOT have the partial flag set (%x)",
1091 lookup_msg(attr_str, attr_code, NULL), flags);
1092 return 1;
1093 }
1094 }
1095
1096 /* Optional transitive attributes may go through speakers that don't
1097 * reocgnise them and set the Partial bit.
1098 */
1099 if (CHECK_FLAG(flags, BGP_ATTR_FLAG_OPTIONAL)
1100 && CHECK_FLAG(flags, BGP_ATTR_FLAG_TRANS))
1101 SET_FLAG(mask, BGP_ATTR_FLAG_PARTIAL);
1102
1103 if ((flags & ~mask) == attr_flags_values[attr_code])
1104 return 0;
1105
1106 bgp_attr_flags_diagnose(args, attr_flags_values[attr_code]);
1107 return 1;
1108 }
1109
1110 /* Get origin attribute of the update message. */
1111 static bgp_attr_parse_ret_t bgp_attr_origin(struct bgp_attr_parser_args *args)
1112 {
1113 struct peer *const peer = args->peer;
1114 struct attr *const attr = args->attr;
1115 const bgp_size_t length = args->length;
1116
1117 /* If any recognized attribute has Attribute Length that conflicts
1118 with the expected length (based on the attribute type code), then
1119 the Error Subcode is set to Attribute Length Error. The Data
1120 field contains the erroneous attribute (type, length and
1121 value). */
1122 if (length != 1) {
1123 zlog_err("Origin attribute length is not one %d", length);
1124 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1125 args->total);
1126 }
1127
1128 /* Fetch origin attribute. */
1129 attr->origin = stream_getc(BGP_INPUT(peer));
1130
1131 /* If the ORIGIN attribute has an undefined value, then the Error
1132 Subcode is set to Invalid Origin Attribute. The Data field
1133 contains the unrecognized attribute (type, length and value). */
1134 if ((attr->origin != BGP_ORIGIN_IGP) && (attr->origin != BGP_ORIGIN_EGP)
1135 && (attr->origin != BGP_ORIGIN_INCOMPLETE)) {
1136 zlog_err("Origin attribute value is invalid %d", attr->origin);
1137 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_INVAL_ORIGIN,
1138 args->total);
1139 }
1140
1141 /* Set oring attribute flag. */
1142 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_ORIGIN);
1143
1144 return 0;
1145 }
1146
1147 /* Parse AS path information. This function is wrapper of
1148 aspath_parse. */
1149 static int bgp_attr_aspath(struct bgp_attr_parser_args *args)
1150 {
1151 struct attr *const attr = args->attr;
1152 struct peer *const peer = args->peer;
1153 const bgp_size_t length = args->length;
1154
1155 /*
1156 * peer with AS4 => will get 4Byte ASnums
1157 * otherwise, will get 16 Bit
1158 */
1159 attr->aspath = aspath_parse(peer->curr, length,
1160 CHECK_FLAG(peer->cap, PEER_CAP_AS4_RCV));
1161
1162 /* In case of IBGP, length will be zero. */
1163 if (!attr->aspath) {
1164 zlog_err("Malformed AS path from %s, length is %d", peer->host,
1165 length);
1166 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_MAL_AS_PATH,
1167 0);
1168 }
1169
1170 /* Set aspath attribute flag. */
1171 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_AS_PATH);
1172
1173 return BGP_ATTR_PARSE_PROCEED;
1174 }
1175
1176 static bgp_attr_parse_ret_t bgp_attr_aspath_check(struct peer *const peer,
1177 struct attr *const attr)
1178 {
1179 /* These checks were part of bgp_attr_aspath, but with
1180 * as4 we should to check aspath things when
1181 * aspath synthesizing with as4_path has already taken place.
1182 * Otherwise we check ASPATH and use the synthesized thing, and that is
1183 * not right.
1184 * So do the checks later, i.e. here
1185 */
1186 struct bgp *bgp = peer->bgp;
1187 struct aspath *aspath;
1188
1189 /* Confederation sanity check. */
1190 if ((peer->sort == BGP_PEER_CONFED
1191 && !aspath_left_confed_check(attr->aspath))
1192 || (peer->sort == BGP_PEER_EBGP
1193 && aspath_confed_check(attr->aspath))) {
1194 zlog_err("Malformed AS path from %s", peer->host);
1195 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
1196 BGP_NOTIFY_UPDATE_MAL_AS_PATH);
1197 return BGP_ATTR_PARSE_ERROR;
1198 }
1199
1200 /* First AS check for EBGP. */
1201 if (bgp != NULL && bgp_flag_check(bgp, BGP_FLAG_ENFORCE_FIRST_AS)) {
1202 if (peer->sort == BGP_PEER_EBGP
1203 && !aspath_firstas_check(attr->aspath, peer->as)) {
1204 zlog_err("%s incorrect first AS (must be %u)",
1205 peer->host, peer->as);
1206 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
1207 BGP_NOTIFY_UPDATE_MAL_AS_PATH);
1208 return BGP_ATTR_PARSE_ERROR;
1209 }
1210 }
1211
1212 /* local-as prepend */
1213 if (peer->change_local_as
1214 && !CHECK_FLAG(peer->flags, PEER_FLAG_LOCAL_AS_NO_PREPEND)) {
1215 aspath = aspath_dup(attr->aspath);
1216 aspath = aspath_add_seq(aspath, peer->change_local_as);
1217 aspath_unintern(&attr->aspath);
1218 attr->aspath = aspath_intern(aspath);
1219 }
1220
1221 return BGP_ATTR_PARSE_PROCEED;
1222 }
1223
1224 /* Parse AS4 path information. This function is another wrapper of
1225 aspath_parse. */
1226 static int bgp_attr_as4_path(struct bgp_attr_parser_args *args,
1227 struct aspath **as4_path)
1228 {
1229 struct peer *const peer = args->peer;
1230 struct attr *const attr = args->attr;
1231 const bgp_size_t length = args->length;
1232
1233 *as4_path = aspath_parse(peer->curr, length, 1);
1234
1235 /* In case of IBGP, length will be zero. */
1236 if (!*as4_path) {
1237 zlog_err("Malformed AS4 path from %s, length is %d", peer->host,
1238 length);
1239 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_MAL_AS_PATH,
1240 0);
1241 }
1242
1243 /* Set aspath attribute flag. */
1244 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_AS4_PATH);
1245
1246 return BGP_ATTR_PARSE_PROCEED;
1247 }
1248
1249 /* Nexthop attribute. */
1250 static bgp_attr_parse_ret_t bgp_attr_nexthop(struct bgp_attr_parser_args *args)
1251 {
1252 struct peer *const peer = args->peer;
1253 struct attr *const attr = args->attr;
1254 const bgp_size_t length = args->length;
1255
1256 in_addr_t nexthop_h, nexthop_n;
1257
1258 /* Check nexthop attribute length. */
1259 if (length != 4) {
1260 zlog_err("Nexthop attribute length isn't four [%d]", length);
1261
1262 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1263 args->total);
1264 }
1265
1266 /* According to section 6.3 of RFC4271, syntactically incorrect NEXT_HOP
1267 attribute must result in a NOTIFICATION message (this is implemented
1268 below).
1269 At the same time, semantically incorrect NEXT_HOP is more likely to
1270 be just
1271 logged locally (this is implemented somewhere else). The UPDATE
1272 message
1273 gets ignored in any of these cases. */
1274 nexthop_n = stream_get_ipv4(peer->curr);
1275 nexthop_h = ntohl(nexthop_n);
1276 if ((IPV4_NET0(nexthop_h) || IPV4_NET127(nexthop_h)
1277 || IPV4_CLASS_DE(nexthop_h))
1278 && !BGP_DEBUG(
1279 allow_martians,
1280 ALLOW_MARTIANS)) /* loopbacks may be used in testing */
1281 {
1282 char buf[INET_ADDRSTRLEN];
1283 inet_ntop(AF_INET, &nexthop_n, buf, INET_ADDRSTRLEN);
1284 zlog_err("Martian nexthop %s", buf);
1285 return bgp_attr_malformed(
1286 args, BGP_NOTIFY_UPDATE_INVAL_NEXT_HOP, args->total);
1287 }
1288
1289 attr->nexthop.s_addr = nexthop_n;
1290 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_NEXT_HOP);
1291
1292 return BGP_ATTR_PARSE_PROCEED;
1293 }
1294
1295 /* MED atrribute. */
1296 static bgp_attr_parse_ret_t bgp_attr_med(struct bgp_attr_parser_args *args)
1297 {
1298 struct peer *const peer = args->peer;
1299 struct attr *const attr = args->attr;
1300 const bgp_size_t length = args->length;
1301
1302 /* Length check. */
1303 if (length != 4) {
1304 zlog_err("MED attribute length isn't four [%d]", length);
1305
1306 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1307 args->total);
1308 }
1309
1310 attr->med = stream_getl(peer->curr);
1311
1312 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_MULTI_EXIT_DISC);
1313
1314 return BGP_ATTR_PARSE_PROCEED;
1315 }
1316
1317 /* Local preference attribute. */
1318 static bgp_attr_parse_ret_t
1319 bgp_attr_local_pref(struct bgp_attr_parser_args *args)
1320 {
1321 struct peer *const peer = args->peer;
1322 struct attr *const attr = args->attr;
1323 const bgp_size_t length = args->length;
1324
1325 /* Length check. */
1326 if (length != 4) {
1327 zlog_err("LOCAL_PREF attribute length isn't 4 [%u]", length);
1328 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1329 args->total);
1330 }
1331
1332 /* If it is contained in an UPDATE message that is received from an
1333 external peer, then this attribute MUST be ignored by the
1334 receiving speaker. */
1335 if (peer->sort == BGP_PEER_EBGP) {
1336 stream_forward_getp(peer->curr, length);
1337 return BGP_ATTR_PARSE_PROCEED;
1338 }
1339
1340 attr->local_pref = stream_getl(peer->curr);
1341
1342 /* Set the local-pref flag. */
1343 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_LOCAL_PREF);
1344
1345 return BGP_ATTR_PARSE_PROCEED;
1346 }
1347
1348 /* Atomic aggregate. */
1349 static int bgp_attr_atomic(struct bgp_attr_parser_args *args)
1350 {
1351 struct attr *const attr = args->attr;
1352 const bgp_size_t length = args->length;
1353
1354 /* Length check. */
1355 if (length != 0) {
1356 zlog_err("ATOMIC_AGGREGATE attribute length isn't 0 [%u]",
1357 length);
1358 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1359 args->total);
1360 }
1361
1362 /* Set atomic aggregate flag. */
1363 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_ATOMIC_AGGREGATE);
1364
1365 return BGP_ATTR_PARSE_PROCEED;
1366 }
1367
1368 /* Aggregator attribute */
1369 static int bgp_attr_aggregator(struct bgp_attr_parser_args *args)
1370 {
1371 struct peer *const peer = args->peer;
1372 struct attr *const attr = args->attr;
1373 const bgp_size_t length = args->length;
1374
1375 int wantedlen = 6;
1376
1377 /* peer with AS4 will send 4 Byte AS, peer without will send 2 Byte */
1378 if (CHECK_FLAG(peer->cap, PEER_CAP_AS4_RCV))
1379 wantedlen = 8;
1380
1381 if (length != wantedlen) {
1382 zlog_err("AGGREGATOR attribute length isn't %u [%u]", wantedlen,
1383 length);
1384 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1385 args->total);
1386 }
1387
1388 if (CHECK_FLAG(peer->cap, PEER_CAP_AS4_RCV))
1389 attr->aggregator_as = stream_getl(peer->curr);
1390 else
1391 attr->aggregator_as = stream_getw(peer->curr);
1392 attr->aggregator_addr.s_addr = stream_get_ipv4(peer->curr);
1393
1394 /* Set atomic aggregate flag. */
1395 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_AGGREGATOR);
1396
1397 return BGP_ATTR_PARSE_PROCEED;
1398 }
1399
1400 /* New Aggregator attribute */
1401 static bgp_attr_parse_ret_t
1402 bgp_attr_as4_aggregator(struct bgp_attr_parser_args *args,
1403 as_t *as4_aggregator_as,
1404 struct in_addr *as4_aggregator_addr)
1405 {
1406 struct peer *const peer = args->peer;
1407 struct attr *const attr = args->attr;
1408 const bgp_size_t length = args->length;
1409
1410 if (length != 8) {
1411 zlog_err("New Aggregator length is not 8 [%d]", length);
1412 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1413 0);
1414 }
1415
1416 *as4_aggregator_as = stream_getl(peer->curr);
1417 as4_aggregator_addr->s_addr = stream_get_ipv4(peer->curr);
1418
1419 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_AS4_AGGREGATOR);
1420
1421 return BGP_ATTR_PARSE_PROCEED;
1422 }
1423
1424 /* Munge Aggregator and New-Aggregator, AS_PATH and NEW_AS_PATH.
1425 */
1426 static bgp_attr_parse_ret_t
1427 bgp_attr_munge_as4_attrs(struct peer *const peer, struct attr *const attr,
1428 struct aspath *as4_path, as_t as4_aggregator,
1429 struct in_addr *as4_aggregator_addr)
1430 {
1431 int ignore_as4_path = 0;
1432 struct aspath *newpath;
1433
1434 if (!attr->aspath) {
1435 /* NULL aspath shouldn't be possible as bgp_attr_parse should
1436 * have
1437 * checked that all well-known, mandatory attributes were
1438 * present.
1439 *
1440 * Can only be a problem with peer itself - hard error
1441 */
1442 return BGP_ATTR_PARSE_ERROR;
1443 }
1444
1445 if (CHECK_FLAG(peer->cap, PEER_CAP_AS4_RCV)) {
1446 /* peer can do AS4, so we ignore AS4_PATH and AS4_AGGREGATOR
1447 * if given.
1448 * It is worth a warning though, because the peer really
1449 * should not send them
1450 */
1451 if (BGP_DEBUG(as4, AS4)) {
1452 if (attr->flag & (ATTR_FLAG_BIT(BGP_ATTR_AS4_PATH)))
1453 zlog_debug("[AS4] %s %s AS4_PATH", peer->host,
1454 "AS4 capable peer, yet it sent");
1455
1456 if (attr->flag
1457 & (ATTR_FLAG_BIT(BGP_ATTR_AS4_AGGREGATOR)))
1458 zlog_debug("[AS4] %s %s AS4_AGGREGATOR",
1459 peer->host,
1460 "AS4 capable peer, yet it sent");
1461 }
1462
1463 return BGP_ATTR_PARSE_PROCEED;
1464 }
1465
1466 /* We have a asn16 peer. First, look for AS4_AGGREGATOR
1467 * because that may override AS4_PATH
1468 */
1469 if (attr->flag & (ATTR_FLAG_BIT(BGP_ATTR_AS4_AGGREGATOR))) {
1470 if (attr->flag & (ATTR_FLAG_BIT(BGP_ATTR_AGGREGATOR))) {
1471 /* received both.
1472 * if the as_number in aggregator is not AS_TRANS,
1473 * then AS4_AGGREGATOR and AS4_PATH shall be ignored
1474 * and the Aggregator shall be taken as
1475 * info on the aggregating node, and the AS_PATH
1476 * shall be taken as the AS_PATH
1477 * otherwise
1478 * the Aggregator shall be ignored and the
1479 * AS4_AGGREGATOR shall be taken as the
1480 * Aggregating node and the AS_PATH is to be
1481 * constructed "as in all other cases"
1482 */
1483 if (attr->aggregator_as != BGP_AS_TRANS) {
1484 /* ignore */
1485 if (BGP_DEBUG(as4, AS4))
1486 zlog_debug(
1487 "[AS4] %s BGP not AS4 capable peer"
1488 " send AGGREGATOR != AS_TRANS and"
1489 " AS4_AGGREGATOR, so ignore"
1490 " AS4_AGGREGATOR and AS4_PATH",
1491 peer->host);
1492 ignore_as4_path = 1;
1493 } else {
1494 /* "New_aggregator shall be taken as aggregator"
1495 */
1496 attr->aggregator_as = as4_aggregator;
1497 attr->aggregator_addr.s_addr =
1498 as4_aggregator_addr->s_addr;
1499 }
1500 } else {
1501 /* We received a AS4_AGGREGATOR but no AGGREGATOR.
1502 * That is bogus - but reading the conditions
1503 * we have to handle AS4_AGGREGATOR as if it were
1504 * AGGREGATOR in that case
1505 */
1506 if (BGP_DEBUG(as4, AS4))
1507 zlog_debug(
1508 "[AS4] %s BGP not AS4 capable peer send"
1509 " AS4_AGGREGATOR but no AGGREGATOR, will take"
1510 " it as if AGGREGATOR with AS_TRANS had been there",
1511 peer->host);
1512 attr->aggregator_as = as4_aggregator;
1513 /* sweep it under the carpet and simulate a "good"
1514 * AGGREGATOR */
1515 attr->flag |= (ATTR_FLAG_BIT(BGP_ATTR_AGGREGATOR));
1516 }
1517 }
1518
1519 /* need to reconcile NEW_AS_PATH and AS_PATH */
1520 if (!ignore_as4_path
1521 && (attr->flag & (ATTR_FLAG_BIT(BGP_ATTR_AS4_PATH)))) {
1522 newpath = aspath_reconcile_as4(attr->aspath, as4_path);
1523 aspath_unintern(&attr->aspath);
1524 attr->aspath = aspath_intern(newpath);
1525 }
1526 return BGP_ATTR_PARSE_PROCEED;
1527 }
1528
1529 /* Community attribute. */
1530 static bgp_attr_parse_ret_t
1531 bgp_attr_community(struct bgp_attr_parser_args *args)
1532 {
1533 struct peer *const peer = args->peer;
1534 struct attr *const attr = args->attr;
1535 const bgp_size_t length = args->length;
1536
1537 if (length == 0) {
1538 attr->community = NULL;
1539 return BGP_ATTR_PARSE_PROCEED;
1540 }
1541
1542 attr->community =
1543 community_parse((u_int32_t *)stream_pnt(peer->curr), length);
1544
1545 /* XXX: fix community_parse to use stream API and remove this */
1546 stream_forward_getp(peer->curr, length);
1547
1548 if (!attr->community)
1549 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
1550 args->total);
1551
1552 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_COMMUNITIES);
1553
1554 return BGP_ATTR_PARSE_PROCEED;
1555 }
1556
1557 /* Originator ID attribute. */
1558 static bgp_attr_parse_ret_t
1559 bgp_attr_originator_id(struct bgp_attr_parser_args *args)
1560 {
1561 struct peer *const peer = args->peer;
1562 struct attr *const attr = args->attr;
1563 const bgp_size_t length = args->length;
1564
1565 /* Length check. */
1566 if (length != 4) {
1567 zlog_err("Bad originator ID length %d", length);
1568
1569 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1570 args->total);
1571 }
1572
1573 attr->originator_id.s_addr = stream_get_ipv4(peer->curr);
1574
1575 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_ORIGINATOR_ID);
1576
1577 return BGP_ATTR_PARSE_PROCEED;
1578 }
1579
1580 /* Cluster list attribute. */
1581 static bgp_attr_parse_ret_t
1582 bgp_attr_cluster_list(struct bgp_attr_parser_args *args)
1583 {
1584 struct peer *const peer = args->peer;
1585 struct attr *const attr = args->attr;
1586 const bgp_size_t length = args->length;
1587
1588 /* Check length. */
1589 if (length % 4) {
1590 zlog_err("Bad cluster list length %d", length);
1591
1592 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1593 args->total);
1594 }
1595
1596 attr->cluster =
1597 cluster_parse((struct in_addr *)stream_pnt(peer->curr), length);
1598
1599 /* XXX: Fix cluster_parse to use stream API and then remove this */
1600 stream_forward_getp(peer->curr, length);
1601
1602 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_CLUSTER_LIST);
1603
1604 return BGP_ATTR_PARSE_PROCEED;
1605 }
1606
1607 /* Multiprotocol reachability information parse. */
1608 int bgp_mp_reach_parse(struct bgp_attr_parser_args *args,
1609 struct bgp_nlri *mp_update)
1610 {
1611 iana_afi_t pkt_afi;
1612 afi_t afi;
1613 iana_safi_t pkt_safi;
1614 safi_t safi;
1615 bgp_size_t nlri_len;
1616 size_t start;
1617 struct stream *s;
1618 struct peer *const peer = args->peer;
1619 struct attr *const attr = args->attr;
1620 const bgp_size_t length = args->length;
1621
1622 /* Set end of packet. */
1623 s = BGP_INPUT(peer);
1624 start = stream_get_getp(s);
1625
1626 /* safe to read statically sized header? */
1627 #define BGP_MP_REACH_MIN_SIZE 5
1628 #define LEN_LEFT (length - (stream_get_getp(s) - start))
1629 if ((length > STREAM_READABLE(s)) || (length < BGP_MP_REACH_MIN_SIZE)) {
1630 zlog_info("%s: %s sent invalid length, %lu", __func__,
1631 peer->host, (unsigned long)length);
1632 return BGP_ATTR_PARSE_ERROR_NOTIFYPLS;
1633 }
1634
1635 /* Load AFI, SAFI. */
1636 pkt_afi = stream_getw(s);
1637 pkt_safi = stream_getc(s);
1638
1639 /* Convert AFI, SAFI to internal values, check. */
1640 if (bgp_map_afi_safi_iana2int(pkt_afi, pkt_safi, &afi, &safi)) {
1641 /* Log if AFI or SAFI is unrecognized. This is not an error
1642 * unless
1643 * the attribute is otherwise malformed.
1644 */
1645 if (bgp_debug_update(peer, NULL, NULL, 0))
1646 zlog_debug(
1647 "%s: MP_REACH received AFI %u or SAFI %u is unrecognized",
1648 peer->host, pkt_afi, pkt_safi);
1649 return BGP_ATTR_PARSE_ERROR;
1650 }
1651
1652 /* Get nexthop length. */
1653 attr->mp_nexthop_len = stream_getc(s);
1654
1655 if (LEN_LEFT < attr->mp_nexthop_len) {
1656 zlog_info(
1657 "%s: %s, MP nexthop length, %u, goes past end of attribute",
1658 __func__, peer->host, attr->mp_nexthop_len);
1659 return BGP_ATTR_PARSE_ERROR_NOTIFYPLS;
1660 }
1661
1662 /* Nexthop length check. */
1663 switch (attr->mp_nexthop_len) {
1664 case BGP_ATTR_NHLEN_VPNV4:
1665 stream_getl(s); /* RD high */
1666 stream_getl(s); /* RD low */
1667 /*
1668 * NOTE: intentional fall through
1669 * - for consistency in rx processing
1670 */
1671 case BGP_ATTR_NHLEN_IPV4:
1672 stream_get(&attr->mp_nexthop_global_in, s, IPV4_MAX_BYTELEN);
1673 /* Probably needed for RFC 2283 */
1674 if (attr->nexthop.s_addr == 0)
1675 memcpy(&attr->nexthop.s_addr,
1676 &attr->mp_nexthop_global_in, IPV4_MAX_BYTELEN);
1677 break;
1678 case BGP_ATTR_NHLEN_IPV6_GLOBAL:
1679 case BGP_ATTR_NHLEN_VPNV6_GLOBAL:
1680 if (attr->mp_nexthop_len == BGP_ATTR_NHLEN_VPNV6_GLOBAL) {
1681 stream_getl(s); /* RD high */
1682 stream_getl(s); /* RD low */
1683 }
1684 stream_get(&attr->mp_nexthop_global, s, IPV6_MAX_BYTELEN);
1685 break;
1686 case BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL:
1687 case BGP_ATTR_NHLEN_VPNV6_GLOBAL_AND_LL:
1688 if (attr->mp_nexthop_len
1689 == BGP_ATTR_NHLEN_VPNV6_GLOBAL_AND_LL) {
1690 stream_getl(s); /* RD high */
1691 stream_getl(s); /* RD low */
1692 }
1693 stream_get(&attr->mp_nexthop_global, s, IPV6_MAX_BYTELEN);
1694 if (attr->mp_nexthop_len
1695 == BGP_ATTR_NHLEN_VPNV6_GLOBAL_AND_LL) {
1696 stream_getl(s); /* RD high */
1697 stream_getl(s); /* RD low */
1698 }
1699 stream_get(&attr->mp_nexthop_local, s, IPV6_MAX_BYTELEN);
1700 if (!IN6_IS_ADDR_LINKLOCAL(&attr->mp_nexthop_local)) {
1701 char buf1[INET6_ADDRSTRLEN];
1702 char buf2[INET6_ADDRSTRLEN];
1703
1704 if (bgp_debug_update(peer, NULL, NULL, 1))
1705 zlog_debug(
1706 "%s rcvd nexthops %s, %s -- ignoring non-LL value",
1707 peer->host,
1708 inet_ntop(AF_INET6,
1709 &attr->mp_nexthop_global,
1710 buf1, INET6_ADDRSTRLEN),
1711 inet_ntop(AF_INET6,
1712 &attr->mp_nexthop_local, buf2,
1713 INET6_ADDRSTRLEN));
1714
1715 attr->mp_nexthop_len = IPV6_MAX_BYTELEN;
1716 }
1717 break;
1718 default:
1719 zlog_info("%s: (%s) Wrong multiprotocol next hop length: %d",
1720 __func__, peer->host, attr->mp_nexthop_len);
1721 return BGP_ATTR_PARSE_ERROR_NOTIFYPLS;
1722 }
1723
1724 if (!LEN_LEFT) {
1725 zlog_info("%s: (%s) Failed to read SNPA and NLRI(s)", __func__,
1726 peer->host);
1727 return BGP_ATTR_PARSE_ERROR_NOTIFYPLS;
1728 }
1729
1730 {
1731 u_char val;
1732 if ((val = stream_getc(s)))
1733 zlog_warn(
1734 "%s sent non-zero value, %u, for defunct SNPA-length field",
1735 peer->host, val);
1736 }
1737
1738 /* must have nrli_len, what is left of the attribute */
1739 nlri_len = LEN_LEFT;
1740 if (nlri_len > STREAM_READABLE(s)) {
1741 zlog_info("%s: (%s) Failed to read NLRI", __func__, peer->host);
1742 return BGP_ATTR_PARSE_ERROR_NOTIFYPLS;
1743 }
1744
1745 if (!nlri_len) {
1746 zlog_info("%s: (%s) No Reachability, Treating as a EOR marker",
1747 __func__, peer->host);
1748
1749 mp_update->afi = afi;
1750 mp_update->safi = safi;
1751 return BGP_ATTR_PARSE_EOR;
1752 }
1753
1754 mp_update->afi = afi;
1755 mp_update->safi = safi;
1756 mp_update->nlri = stream_pnt(s);
1757 mp_update->length = nlri_len;
1758
1759 stream_forward_getp(s, nlri_len);
1760
1761 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_MP_REACH_NLRI);
1762
1763 return BGP_ATTR_PARSE_PROCEED;
1764 #undef LEN_LEFT
1765 }
1766
1767 /* Multiprotocol unreachable parse */
1768 int bgp_mp_unreach_parse(struct bgp_attr_parser_args *args,
1769 struct bgp_nlri *mp_withdraw)
1770 {
1771 struct stream *s;
1772 iana_afi_t pkt_afi;
1773 afi_t afi;
1774 iana_safi_t pkt_safi;
1775 safi_t safi;
1776 u_int16_t withdraw_len;
1777 struct peer *const peer = args->peer;
1778 struct attr *const attr = args->attr;
1779 const bgp_size_t length = args->length;
1780
1781 s = peer->curr;
1782
1783 #define BGP_MP_UNREACH_MIN_SIZE 3
1784 if ((length > STREAM_READABLE(s)) || (length < BGP_MP_UNREACH_MIN_SIZE))
1785 return BGP_ATTR_PARSE_ERROR_NOTIFYPLS;
1786
1787 pkt_afi = stream_getw(s);
1788 pkt_safi = stream_getc(s);
1789
1790 /* Convert AFI, SAFI to internal values, check. */
1791 if (bgp_map_afi_safi_iana2int(pkt_afi, pkt_safi, &afi, &safi)) {
1792 /* Log if AFI or SAFI is unrecognized. This is not an error
1793 * unless
1794 * the attribute is otherwise malformed.
1795 */
1796 if (bgp_debug_update(peer, NULL, NULL, 0))
1797 zlog_debug(
1798 "%s: MP_UNREACH received AFI %u or SAFI %u is unrecognized",
1799 peer->host, pkt_afi, pkt_safi);
1800 return BGP_ATTR_PARSE_ERROR;
1801 }
1802
1803 withdraw_len = length - BGP_MP_UNREACH_MIN_SIZE;
1804
1805 mp_withdraw->afi = afi;
1806 mp_withdraw->safi = safi;
1807 mp_withdraw->nlri = stream_pnt(s);
1808 mp_withdraw->length = withdraw_len;
1809
1810 stream_forward_getp(s, withdraw_len);
1811
1812 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_MP_UNREACH_NLRI);
1813
1814 return BGP_ATTR_PARSE_PROCEED;
1815 }
1816
1817 /* Large Community attribute. */
1818 static bgp_attr_parse_ret_t
1819 bgp_attr_large_community(struct bgp_attr_parser_args *args)
1820 {
1821 struct peer *const peer = args->peer;
1822 struct attr *const attr = args->attr;
1823 const bgp_size_t length = args->length;
1824
1825 /*
1826 * Large community follows new attribute format.
1827 */
1828 if (length == 0) {
1829 attr->lcommunity = NULL;
1830 /* Empty extcomm doesn't seem to be invalid per se */
1831 return BGP_ATTR_PARSE_PROCEED;
1832 }
1833
1834 attr->lcommunity =
1835 lcommunity_parse((u_int8_t *)stream_pnt(peer->curr), length);
1836 /* XXX: fix ecommunity_parse to use stream API */
1837 stream_forward_getp(peer->curr, length);
1838
1839 if (!attr->lcommunity)
1840 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
1841 args->total);
1842
1843 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_LARGE_COMMUNITIES);
1844
1845 return BGP_ATTR_PARSE_PROCEED;
1846 }
1847
1848 /* Extended Community attribute. */
1849 static bgp_attr_parse_ret_t
1850 bgp_attr_ext_communities(struct bgp_attr_parser_args *args)
1851 {
1852 struct peer *const peer = args->peer;
1853 struct attr *const attr = args->attr;
1854 const bgp_size_t length = args->length;
1855 u_char sticky = 0;
1856
1857 if (length == 0) {
1858 attr->ecommunity = NULL;
1859 /* Empty extcomm doesn't seem to be invalid per se */
1860 return BGP_ATTR_PARSE_PROCEED;
1861 }
1862
1863 attr->ecommunity =
1864 ecommunity_parse((u_int8_t *)stream_pnt(peer->curr), length);
1865 /* XXX: fix ecommunity_parse to use stream API */
1866 stream_forward_getp(peer->curr, length);
1867
1868 if (!attr->ecommunity)
1869 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
1870 args->total);
1871
1872 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_EXT_COMMUNITIES);
1873
1874 /* Extract MAC mobility sequence number, if any. */
1875 attr->mm_seqnum = bgp_attr_mac_mobility_seqnum(attr, &sticky);
1876 attr->sticky = sticky;
1877
1878 return BGP_ATTR_PARSE_PROCEED;
1879 }
1880
1881 /* Parse Tunnel Encap attribute in an UPDATE */
1882 static int bgp_attr_encap(uint8_t type, struct peer *peer, /* IN */
1883 bgp_size_t length, /* IN: attr's length field */
1884 struct attr *attr, /* IN: caller already allocated */
1885 u_char flag, /* IN: attr's flags field */
1886 u_char *startp)
1887 {
1888 bgp_size_t total;
1889 uint16_t tunneltype = 0;
1890
1891 total = length + (CHECK_FLAG(flag, BGP_ATTR_FLAG_EXTLEN) ? 4 : 3);
1892
1893 if (!CHECK_FLAG(flag, BGP_ATTR_FLAG_TRANS)
1894 || !CHECK_FLAG(flag, BGP_ATTR_FLAG_OPTIONAL)) {
1895 zlog_info(
1896 "Tunnel Encap attribute flag isn't optional and transitive %d",
1897 flag);
1898 bgp_notify_send_with_data(peer, BGP_NOTIFY_UPDATE_ERR,
1899 BGP_NOTIFY_UPDATE_ATTR_FLAG_ERR,
1900 startp, total);
1901 return -1;
1902 }
1903
1904 if (BGP_ATTR_ENCAP == type) {
1905 /* read outer TLV type and length */
1906 uint16_t tlv_length;
1907
1908 if (length < 4) {
1909 zlog_info(
1910 "Tunnel Encap attribute not long enough to contain outer T,L");
1911 bgp_notify_send_with_data(
1912 peer, BGP_NOTIFY_UPDATE_ERR,
1913 BGP_NOTIFY_UPDATE_OPT_ATTR_ERR, startp, total);
1914 return -1;
1915 }
1916 tunneltype = stream_getw(BGP_INPUT(peer));
1917 tlv_length = stream_getw(BGP_INPUT(peer));
1918 length -= 4;
1919
1920 if (tlv_length != length) {
1921 zlog_info("%s: tlv_length(%d) != length(%d)", __func__,
1922 tlv_length, length);
1923 }
1924 }
1925
1926 while (length >= 4) {
1927 uint16_t subtype = 0;
1928 uint16_t sublength = 0;
1929 struct bgp_attr_encap_subtlv *tlv;
1930
1931 if (BGP_ATTR_ENCAP == type) {
1932 subtype = stream_getc(BGP_INPUT(peer));
1933 sublength = stream_getc(BGP_INPUT(peer));
1934 length -= 2;
1935 #if ENABLE_BGP_VNC
1936 } else {
1937 subtype = stream_getw(BGP_INPUT(peer));
1938 sublength = stream_getw(BGP_INPUT(peer));
1939 length -= 4;
1940 #endif
1941 }
1942
1943 if (sublength > length) {
1944 zlog_info(
1945 "Tunnel Encap attribute sub-tlv length %d exceeds remaining length %d",
1946 sublength, length);
1947 bgp_notify_send_with_data(
1948 peer, BGP_NOTIFY_UPDATE_ERR,
1949 BGP_NOTIFY_UPDATE_OPT_ATTR_ERR, startp, total);
1950 return -1;
1951 }
1952
1953 /* alloc and copy sub-tlv */
1954 /* TBD make sure these are freed when attributes are released */
1955 tlv = XCALLOC(MTYPE_ENCAP_TLV,
1956 sizeof(struct bgp_attr_encap_subtlv)
1957 + sublength);
1958 tlv->type = subtype;
1959 tlv->length = sublength;
1960 stream_get(tlv->value, peer->curr, sublength);
1961 length -= sublength;
1962
1963 /* attach tlv to encap chain */
1964 if (BGP_ATTR_ENCAP == type) {
1965 struct bgp_attr_encap_subtlv *stlv_last;
1966 for (stlv_last = attr->encap_subtlvs;
1967 stlv_last && stlv_last->next;
1968 stlv_last = stlv_last->next)
1969 ;
1970 if (stlv_last) {
1971 stlv_last->next = tlv;
1972 } else {
1973 attr->encap_subtlvs = tlv;
1974 }
1975 #if ENABLE_BGP_VNC
1976 } else {
1977 struct bgp_attr_encap_subtlv *stlv_last;
1978 for (stlv_last = attr->vnc_subtlvs;
1979 stlv_last && stlv_last->next;
1980 stlv_last = stlv_last->next)
1981 ;
1982 if (stlv_last) {
1983 stlv_last->next = tlv;
1984 } else {
1985 attr->vnc_subtlvs = tlv;
1986 }
1987 #endif
1988 }
1989 }
1990
1991 if (BGP_ATTR_ENCAP == type) {
1992 attr->encap_tunneltype = tunneltype;
1993 }
1994
1995 if (length) {
1996 /* spurious leftover data */
1997 zlog_info(
1998 "Tunnel Encap attribute length is bad: %d leftover octets",
1999 length);
2000 bgp_notify_send_with_data(peer, BGP_NOTIFY_UPDATE_ERR,
2001 BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
2002 startp, total);
2003 return -1;
2004 }
2005
2006 return 0;
2007 }
2008
2009 /* Prefix SID attribute
2010 * draft-ietf-idr-bgp-prefix-sid-05
2011 */
2012 static bgp_attr_parse_ret_t
2013 bgp_attr_prefix_sid(struct bgp_attr_parser_args *args,
2014 struct bgp_nlri *mp_update)
2015 {
2016 struct peer *const peer = args->peer;
2017 struct attr *const attr = args->attr;
2018 int type;
2019 int length;
2020 u_int32_t label_index;
2021 struct in6_addr ipv6_sid;
2022 u_int32_t srgb_base;
2023 u_int32_t srgb_range;
2024 int srgb_count;
2025
2026 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_PREFIX_SID);
2027
2028 type = stream_getc(peer->curr);
2029 length = stream_getw(peer->curr);
2030
2031 if (type == BGP_PREFIX_SID_LABEL_INDEX) {
2032 if (length != BGP_PREFIX_SID_LABEL_INDEX_LENGTH) {
2033 zlog_err(
2034 "Prefix SID label index length is %d instead of %d",
2035 length, BGP_PREFIX_SID_LABEL_INDEX_LENGTH);
2036 return bgp_attr_malformed(
2037 args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
2038 args->total);
2039 }
2040
2041 /* Ignore flags and reserved */
2042 stream_getc(peer->curr);
2043 stream_getw(peer->curr);
2044
2045 /* Fetch the label index and see if it is valid. */
2046 label_index = stream_getl(peer->curr);
2047 if (label_index == BGP_INVALID_LABEL_INDEX)
2048 return bgp_attr_malformed(
2049 args, BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
2050 args->total);
2051
2052 /* Store label index; subsequently, we'll check on
2053 * address-family */
2054 attr->label_index = label_index;
2055
2056 /*
2057 * Ignore the Label index attribute unless received for
2058 * labeled-unicast
2059 * SAFI.
2060 */
2061 if (!mp_update->length
2062 || mp_update->safi != SAFI_LABELED_UNICAST)
2063 attr->label_index = BGP_INVALID_LABEL_INDEX;
2064 }
2065
2066 /* Placeholder code for the IPv6 SID type */
2067 else if (type == BGP_PREFIX_SID_IPV6) {
2068 if (length != BGP_PREFIX_SID_IPV6_LENGTH) {
2069 zlog_err("Prefix SID IPv6 length is %d instead of %d",
2070 length, BGP_PREFIX_SID_IPV6_LENGTH);
2071 return bgp_attr_malformed(
2072 args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
2073 args->total);
2074 }
2075
2076 /* Ignore reserved */
2077 stream_getc(peer->curr);
2078 stream_getw(peer->curr);
2079
2080 stream_get(&ipv6_sid, peer->curr, 16);
2081 }
2082
2083 /* Placeholder code for the Originator SRGB type */
2084 else if (type == BGP_PREFIX_SID_ORIGINATOR_SRGB) {
2085 /* Ignore flags */
2086 stream_getw(peer->curr);
2087
2088 length -= 2;
2089
2090 if (length % BGP_PREFIX_SID_ORIGINATOR_SRGB_LENGTH) {
2091 zlog_err(
2092 "Prefix SID Originator SRGB length is %d, it must be a multiple of %d ",
2093 length, BGP_PREFIX_SID_ORIGINATOR_SRGB_LENGTH);
2094 return bgp_attr_malformed(
2095 args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
2096 args->total);
2097 }
2098
2099 srgb_count = length / BGP_PREFIX_SID_ORIGINATOR_SRGB_LENGTH;
2100
2101 for (int i = 0; i < srgb_count; i++) {
2102 stream_get(&srgb_base, peer->curr, 3);
2103 stream_get(&srgb_range, peer->curr, 3);
2104 }
2105 }
2106
2107 return BGP_ATTR_PARSE_PROCEED;
2108 }
2109
2110 /* BGP unknown attribute treatment. */
2111 static bgp_attr_parse_ret_t bgp_attr_unknown(struct bgp_attr_parser_args *args)
2112 {
2113 bgp_size_t total = args->total;
2114 struct transit *transit;
2115 struct peer *const peer = args->peer;
2116 struct attr *const attr = args->attr;
2117 u_char *const startp = args->startp;
2118 const u_char type = args->type;
2119 const u_char flag = args->flags;
2120 const bgp_size_t length = args->length;
2121
2122 if (bgp_debug_update(peer, NULL, NULL, 1))
2123 zlog_debug(
2124 "%s Unknown attribute is received (type %d, length %d)",
2125 peer->host, type, length);
2126
2127 /* Forward read pointer of input stream. */
2128 stream_forward_getp(peer->curr, length);
2129
2130 /* If any of the mandatory well-known attributes are not recognized,
2131 then the Error Subcode is set to Unrecognized Well-known
2132 Attribute. The Data field contains the unrecognized attribute
2133 (type, length and value). */
2134 if (!CHECK_FLAG(flag, BGP_ATTR_FLAG_OPTIONAL)) {
2135 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_UNREC_ATTR,
2136 args->total);
2137 }
2138
2139 /* Unrecognized non-transitive optional attributes must be quietly
2140 ignored and not passed along to other BGP peers. */
2141 if (!CHECK_FLAG(flag, BGP_ATTR_FLAG_TRANS))
2142 return BGP_ATTR_PARSE_PROCEED;
2143
2144 /* If a path with recognized transitive optional attribute is
2145 accepted and passed along to other BGP peers and the Partial bit
2146 in the Attribute Flags octet is set to 1 by some previous AS, it
2147 is not set back to 0 by the current AS. */
2148 SET_FLAG(*startp, BGP_ATTR_FLAG_PARTIAL);
2149
2150 /* Store transitive attribute to the end of attr->transit. */
2151 if (!attr->transit)
2152 attr->transit = XCALLOC(MTYPE_TRANSIT, sizeof(struct transit));
2153
2154 transit = attr->transit;
2155
2156 if (transit->val)
2157 transit->val = XREALLOC(MTYPE_TRANSIT_VAL, transit->val,
2158 transit->length + total);
2159 else
2160 transit->val = XMALLOC(MTYPE_TRANSIT_VAL, total);
2161
2162 memcpy(transit->val + transit->length, startp, total);
2163 transit->length += total;
2164
2165 return BGP_ATTR_PARSE_PROCEED;
2166 }
2167
2168 /* Well-known attribute check. */
2169 static int bgp_attr_check(struct peer *peer, struct attr *attr)
2170 {
2171 u_char type = 0;
2172
2173 /* BGP Graceful-Restart End-of-RIB for IPv4 unicast is signaled as an
2174 * empty UPDATE. */
2175 if (CHECK_FLAG(peer->cap, PEER_CAP_RESTART_RCV) && !attr->flag)
2176 return BGP_ATTR_PARSE_PROCEED;
2177
2178 /* "An UPDATE message that contains the MP_UNREACH_NLRI is not required
2179 to carry any other path attributes.", though if MP_REACH_NLRI or NLRI
2180 are present, it should. Check for any other attribute being present
2181 instead.
2182 */
2183 if (attr->flag == ATTR_FLAG_BIT(BGP_ATTR_MP_UNREACH_NLRI))
2184 return BGP_ATTR_PARSE_PROCEED;
2185
2186 if (!CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_ORIGIN)))
2187 type = BGP_ATTR_ORIGIN;
2188
2189 if (!CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_AS_PATH)))
2190 type = BGP_ATTR_AS_PATH;
2191
2192 /* RFC 2858 makes Next-Hop optional/ignored, if MP_REACH_NLRI is present
2193 * and
2194 * NLRI is empty. We can't easily check NLRI empty here though.
2195 */
2196 if (!CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_NEXT_HOP))
2197 && !CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_MP_REACH_NLRI)))
2198 type = BGP_ATTR_NEXT_HOP;
2199
2200 if (peer->sort == BGP_PEER_IBGP
2201 && !CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_LOCAL_PREF)))
2202 type = BGP_ATTR_LOCAL_PREF;
2203
2204 if (type) {
2205 zlog_warn("%s Missing well-known attribute %s.", peer->host,
2206 lookup_msg(attr_str, type, NULL));
2207 bgp_notify_send_with_data(peer, BGP_NOTIFY_UPDATE_ERR,
2208 BGP_NOTIFY_UPDATE_MISS_ATTR, &type,
2209 1);
2210 return BGP_ATTR_PARSE_ERROR;
2211 }
2212 return BGP_ATTR_PARSE_PROCEED;
2213 }
2214
2215 /* Read attribute of update packet. This function is called from
2216 bgp_update_receive() in bgp_packet.c. */
2217 bgp_attr_parse_ret_t bgp_attr_parse(struct peer *peer, struct attr *attr,
2218 bgp_size_t size, struct bgp_nlri *mp_update,
2219 struct bgp_nlri *mp_withdraw)
2220 {
2221 int ret;
2222 u_char flag = 0;
2223 u_char type = 0;
2224 bgp_size_t length;
2225 u_char *startp, *endp;
2226 u_char *attr_endp;
2227 u_char seen[BGP_ATTR_BITMAP_SIZE];
2228 /* we need the as4_path only until we have synthesized the as_path with
2229 * it */
2230 /* same goes for as4_aggregator */
2231 struct aspath *as4_path = NULL;
2232 as_t as4_aggregator = 0;
2233 struct in_addr as4_aggregator_addr = {.s_addr = 0};
2234
2235 /* Initialize bitmap. */
2236 memset(seen, 0, BGP_ATTR_BITMAP_SIZE);
2237
2238 /* End pointer of BGP attribute. */
2239 endp = BGP_INPUT_PNT(peer) + size;
2240
2241 /* Get attributes to the end of attribute length. */
2242 while (BGP_INPUT_PNT(peer) < endp) {
2243 /* Check remaining length check.*/
2244 if (endp - BGP_INPUT_PNT(peer) < BGP_ATTR_MIN_LEN) {
2245 /* XXX warning: long int format, int arg (arg 5) */
2246 zlog_warn(
2247 "%s: error BGP attribute length %lu is smaller than min len",
2248 peer->host,
2249 (unsigned long)(endp
2250 - stream_pnt(BGP_INPUT(peer))));
2251
2252 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
2253 BGP_NOTIFY_UPDATE_ATTR_LENG_ERR);
2254 return BGP_ATTR_PARSE_ERROR;
2255 }
2256
2257 /* Fetch attribute flag and type. */
2258 startp = BGP_INPUT_PNT(peer);
2259 /* "The lower-order four bits of the Attribute Flags octet are
2260 unused. They MUST be zero when sent and MUST be ignored when
2261 received." */
2262 flag = 0xF0 & stream_getc(BGP_INPUT(peer));
2263 type = stream_getc(BGP_INPUT(peer));
2264
2265 /* Check whether Extended-Length applies and is in bounds */
2266 if (CHECK_FLAG(flag, BGP_ATTR_FLAG_EXTLEN)
2267 && ((endp - startp) < (BGP_ATTR_MIN_LEN + 1))) {
2268 zlog_warn(
2269 "%s: Extended length set, but just %lu bytes of attr header",
2270 peer->host,
2271 (unsigned long)(endp
2272 - stream_pnt(BGP_INPUT(peer))));
2273
2274 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
2275 BGP_NOTIFY_UPDATE_ATTR_LENG_ERR);
2276 return BGP_ATTR_PARSE_ERROR;
2277 }
2278
2279 /* Check extended attribue length bit. */
2280 if (CHECK_FLAG(flag, BGP_ATTR_FLAG_EXTLEN))
2281 length = stream_getw(BGP_INPUT(peer));
2282 else
2283 length = stream_getc(BGP_INPUT(peer));
2284
2285 /* If any attribute appears more than once in the UPDATE
2286 message, then the Error Subcode is set to Malformed Attribute
2287 List. */
2288
2289 if (CHECK_BITMAP(seen, type)) {
2290 zlog_warn(
2291 "%s: error BGP attribute type %d appears twice in a message",
2292 peer->host, type);
2293
2294 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
2295 BGP_NOTIFY_UPDATE_MAL_ATTR);
2296 return BGP_ATTR_PARSE_ERROR;
2297 }
2298
2299 /* Set type to bitmap to check duplicate attribute. `type' is
2300 unsigned char so it never overflow bitmap range. */
2301
2302 SET_BITMAP(seen, type);
2303
2304 /* Overflow check. */
2305 attr_endp = BGP_INPUT_PNT(peer) + length;
2306
2307 if (attr_endp > endp) {
2308 zlog_warn(
2309 "%s: BGP type %d length %d is too large, attribute total length is %d. attr_endp is %p. endp is %p",
2310 peer->host, type, length, size, attr_endp,
2311 endp);
2312 /*
2313 * RFC 4271 6.3
2314 * If any recognized attribute has an Attribute
2315 * Length that conflicts with the expected length
2316 * (based on the attribute type code), then the
2317 * Error Subcode MUST be set to Attribute Length
2318 * Error. The Data field MUST contain the erroneous
2319 * attribute (type, length, and value).
2320 * ----------
2321 * We do not currently have a good way to determine the
2322 * length of the attribute independent of the length
2323 * received in the message. Instead we send the
2324 * minimum between the amount of data we have and the
2325 * amount specified by the attribute length field.
2326 *
2327 * Instead of directly passing in the packet buffer and
2328 * offset we use the stream_get* functions to read into
2329 * a stack buffer, since they perform bounds checking
2330 * and we are working with untrusted data.
2331 */
2332 unsigned char ndata[BGP_MAX_PACKET_SIZE];
2333 memset(ndata, 0x00, sizeof(ndata));
2334 size_t lfl =
2335 CHECK_FLAG(flag, BGP_ATTR_FLAG_EXTLEN) ? 2 : 1;
2336 /* Rewind to end of flag field */
2337 stream_forward_getp(BGP_INPUT(peer), -(1 + lfl));
2338 /* Type */
2339 stream_get(&ndata[0], BGP_INPUT(peer), 1);
2340 /* Length */
2341 stream_get(&ndata[1], BGP_INPUT(peer), lfl);
2342 /* Value */
2343 size_t atl = attr_endp - startp;
2344 size_t ndl = MIN(atl, STREAM_READABLE(BGP_INPUT(peer)));
2345 stream_get(&ndata[lfl + 1], BGP_INPUT(peer), ndl);
2346
2347 bgp_notify_send_with_data(
2348 peer, BGP_NOTIFY_UPDATE_ERR,
2349 BGP_NOTIFY_UPDATE_ATTR_LENG_ERR, ndata,
2350 ndl + lfl + 1);
2351
2352 return BGP_ATTR_PARSE_ERROR;
2353 }
2354
2355 struct bgp_attr_parser_args attr_args = {
2356 .peer = peer,
2357 .length = length,
2358 .attr = attr,
2359 .type = type,
2360 .flags = flag,
2361 .startp = startp,
2362 .total = attr_endp - startp,
2363 };
2364
2365
2366 /* If any recognized attribute has Attribute Flags that conflict
2367 with the Attribute Type Code, then the Error Subcode is set
2368 to
2369 Attribute Flags Error. The Data field contains the erroneous
2370 attribute (type, length and value). */
2371 if (bgp_attr_flag_invalid(&attr_args)) {
2372 bgp_attr_parse_ret_t ret;
2373 ret = bgp_attr_malformed(
2374 &attr_args, BGP_NOTIFY_UPDATE_ATTR_FLAG_ERR,
2375 attr_args.total);
2376 if (ret == BGP_ATTR_PARSE_PROCEED)
2377 continue;
2378 return ret;
2379 }
2380
2381 /* OK check attribute and store it's value. */
2382 switch (type) {
2383 case BGP_ATTR_ORIGIN:
2384 ret = bgp_attr_origin(&attr_args);
2385 break;
2386 case BGP_ATTR_AS_PATH:
2387 ret = bgp_attr_aspath(&attr_args);
2388 break;
2389 case BGP_ATTR_AS4_PATH:
2390 ret = bgp_attr_as4_path(&attr_args, &as4_path);
2391 break;
2392 case BGP_ATTR_NEXT_HOP:
2393 ret = bgp_attr_nexthop(&attr_args);
2394 break;
2395 case BGP_ATTR_MULTI_EXIT_DISC:
2396 ret = bgp_attr_med(&attr_args);
2397 break;
2398 case BGP_ATTR_LOCAL_PREF:
2399 ret = bgp_attr_local_pref(&attr_args);
2400 break;
2401 case BGP_ATTR_ATOMIC_AGGREGATE:
2402 ret = bgp_attr_atomic(&attr_args);
2403 break;
2404 case BGP_ATTR_AGGREGATOR:
2405 ret = bgp_attr_aggregator(&attr_args);
2406 break;
2407 case BGP_ATTR_AS4_AGGREGATOR:
2408 ret = bgp_attr_as4_aggregator(&attr_args,
2409 &as4_aggregator,
2410 &as4_aggregator_addr);
2411 break;
2412 case BGP_ATTR_COMMUNITIES:
2413 ret = bgp_attr_community(&attr_args);
2414 break;
2415 case BGP_ATTR_LARGE_COMMUNITIES:
2416 ret = bgp_attr_large_community(&attr_args);
2417 break;
2418 case BGP_ATTR_ORIGINATOR_ID:
2419 ret = bgp_attr_originator_id(&attr_args);
2420 break;
2421 case BGP_ATTR_CLUSTER_LIST:
2422 ret = bgp_attr_cluster_list(&attr_args);
2423 break;
2424 case BGP_ATTR_MP_REACH_NLRI:
2425 ret = bgp_mp_reach_parse(&attr_args, mp_update);
2426 break;
2427 case BGP_ATTR_MP_UNREACH_NLRI:
2428 ret = bgp_mp_unreach_parse(&attr_args, mp_withdraw);
2429 break;
2430 case BGP_ATTR_EXT_COMMUNITIES:
2431 ret = bgp_attr_ext_communities(&attr_args);
2432 break;
2433 #if ENABLE_BGP_VNC
2434 case BGP_ATTR_VNC:
2435 #endif
2436 case BGP_ATTR_ENCAP:
2437 ret = bgp_attr_encap(type, peer, length, attr, flag,
2438 startp);
2439 break;
2440 case BGP_ATTR_PREFIX_SID:
2441 ret = bgp_attr_prefix_sid(&attr_args, mp_update);
2442 break;
2443 default:
2444 ret = bgp_attr_unknown(&attr_args);
2445 break;
2446 }
2447
2448 if (ret == BGP_ATTR_PARSE_ERROR_NOTIFYPLS) {
2449 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
2450 BGP_NOTIFY_UPDATE_MAL_ATTR);
2451 ret = BGP_ATTR_PARSE_ERROR;
2452 }
2453
2454 if (ret == BGP_ATTR_PARSE_EOR) {
2455 if (as4_path)
2456 aspath_unintern(&as4_path);
2457 return ret;
2458 }
2459
2460 /* If hard error occured immediately return to the caller. */
2461 if (ret == BGP_ATTR_PARSE_ERROR) {
2462 zlog_warn("%s: Attribute %s, parse error", peer->host,
2463 lookup_msg(attr_str, type, NULL));
2464 if (as4_path)
2465 aspath_unintern(&as4_path);
2466 return ret;
2467 }
2468 if (ret == BGP_ATTR_PARSE_WITHDRAW) {
2469
2470 zlog_warn(
2471 "%s: Attribute %s, parse error - treating as withdrawal",
2472 peer->host, lookup_msg(attr_str, type, NULL));
2473 if (as4_path)
2474 aspath_unintern(&as4_path);
2475 return ret;
2476 }
2477
2478 /* Check the fetched length. */
2479 if (BGP_INPUT_PNT(peer) != attr_endp) {
2480 zlog_warn("%s: BGP attribute %s, fetch error",
2481 peer->host, lookup_msg(attr_str, type, NULL));
2482 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
2483 BGP_NOTIFY_UPDATE_ATTR_LENG_ERR);
2484 if (as4_path)
2485 aspath_unintern(&as4_path);
2486 return BGP_ATTR_PARSE_ERROR;
2487 }
2488 }
2489
2490 /* Check final read pointer is same as end pointer. */
2491 if (BGP_INPUT_PNT(peer) != endp) {
2492 zlog_warn("%s: BGP attribute %s, length mismatch", peer->host,
2493 lookup_msg(attr_str, type, NULL));
2494 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
2495 BGP_NOTIFY_UPDATE_ATTR_LENG_ERR);
2496 if (as4_path)
2497 aspath_unintern(&as4_path);
2498 return BGP_ATTR_PARSE_ERROR;
2499 }
2500
2501 /* Check all mandatory well-known attributes are present */
2502 {
2503 bgp_attr_parse_ret_t ret;
2504 if ((ret = bgp_attr_check(peer, attr)) < 0) {
2505 if (as4_path)
2506 aspath_unintern(&as4_path);
2507 return ret;
2508 }
2509 }
2510
2511 /*
2512 * At this place we can see whether we got AS4_PATH and/or
2513 * AS4_AGGREGATOR from a 16Bit peer and act accordingly.
2514 * We can not do this before we've read all attributes because
2515 * the as4 handling does not say whether AS4_PATH has to be sent
2516 * after AS_PATH or not - and when AS4_AGGREGATOR will be send
2517 * in relationship to AGGREGATOR.
2518 * So, to be defensive, we are not relying on any order and read
2519 * all attributes first, including these 32bit ones, and now,
2520 * afterwards, we look what and if something is to be done for as4.
2521 *
2522 * It is possible to not have AS_PATH, e.g. GR EoR and sole
2523 * MP_UNREACH_NLRI.
2524 */
2525 /* actually... this doesn't ever return failure currently, but
2526 * better safe than sorry */
2527 if (CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_AS_PATH))
2528 && bgp_attr_munge_as4_attrs(peer, attr, as4_path, as4_aggregator,
2529 &as4_aggregator_addr)) {
2530 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
2531 BGP_NOTIFY_UPDATE_MAL_ATTR);
2532 if (as4_path)
2533 aspath_unintern(&as4_path);
2534 return BGP_ATTR_PARSE_ERROR;
2535 }
2536
2537 /* At this stage, we have done all fiddling with as4, and the
2538 * resulting info is in attr->aggregator resp. attr->aspath
2539 * so we can chuck as4_aggregator and as4_path alltogether in
2540 * order to save memory
2541 */
2542 if (as4_path) {
2543 aspath_unintern(&as4_path); /* unintern - it is in the hash */
2544 /* The flag that we got this is still there, but that does not
2545 * do any trouble
2546 */
2547 }
2548 /*
2549 * The "rest" of the code does nothing with as4_aggregator.
2550 * there is no memory attached specifically which is not part
2551 * of the attr.
2552 * so ignoring just means do nothing.
2553 */
2554 /*
2555 * Finally do the checks on the aspath we did not do yet
2556 * because we waited for a potentially synthesized aspath.
2557 */
2558 if (attr->flag & (ATTR_FLAG_BIT(BGP_ATTR_AS_PATH))) {
2559 ret = bgp_attr_aspath_check(peer, attr);
2560 if (ret != BGP_ATTR_PARSE_PROCEED)
2561 return ret;
2562 }
2563 /* Finally intern unknown attribute. */
2564 if (attr->transit)
2565 attr->transit = transit_intern(attr->transit);
2566 if (attr->encap_subtlvs)
2567 attr->encap_subtlvs =
2568 encap_intern(attr->encap_subtlvs, ENCAP_SUBTLV_TYPE);
2569 #if ENABLE_BGP_VNC
2570 if (attr->vnc_subtlvs)
2571 attr->vnc_subtlvs =
2572 encap_intern(attr->vnc_subtlvs, VNC_SUBTLV_TYPE);
2573 #endif
2574
2575 return BGP_ATTR_PARSE_PROCEED;
2576 }
2577
2578 size_t bgp_packet_mpattr_start(struct stream *s, struct peer *peer, afi_t afi,
2579 safi_t safi, struct bpacket_attr_vec_arr *vecarr,
2580 struct attr *attr)
2581 {
2582 size_t sizep;
2583 iana_afi_t pkt_afi;
2584 iana_safi_t pkt_safi;
2585 afi_t nh_afi;
2586
2587 /* Set extended bit always to encode the attribute length as 2 bytes */
2588 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_EXTLEN);
2589 stream_putc(s, BGP_ATTR_MP_REACH_NLRI);
2590 sizep = stream_get_endp(s);
2591 stream_putw(s, 0); /* Marker: Attribute length. */
2592
2593
2594 /* Convert AFI, SAFI to values for packet. */
2595 bgp_map_afi_safi_int2iana(afi, safi, &pkt_afi, &pkt_safi);
2596
2597 stream_putw(s, pkt_afi); /* AFI */
2598 stream_putc(s, pkt_safi); /* SAFI */
2599
2600 /* Nexthop AFI */
2601 if (afi == AFI_IP
2602 && (safi == SAFI_UNICAST || safi == SAFI_LABELED_UNICAST))
2603 nh_afi = peer_cap_enhe(peer, afi, safi) ? AFI_IP6 : AFI_IP;
2604 else
2605 nh_afi = BGP_NEXTHOP_AFI_FROM_NHLEN(attr->mp_nexthop_len);
2606
2607 /* Nexthop */
2608 bpacket_attr_vec_arr_set_vec(vecarr, BGP_ATTR_VEC_NH, s, attr);
2609 switch (nh_afi) {
2610 case AFI_IP:
2611 switch (safi) {
2612 case SAFI_UNICAST:
2613 case SAFI_MULTICAST:
2614 case SAFI_LABELED_UNICAST:
2615 stream_putc(s, 4);
2616 stream_put_ipv4(s, attr->nexthop.s_addr);
2617 break;
2618 case SAFI_MPLS_VPN:
2619 stream_putc(s, 12);
2620 stream_putl(s, 0); /* RD = 0, per RFC */
2621 stream_putl(s, 0);
2622 stream_put(s, &attr->mp_nexthop_global_in, 4);
2623 break;
2624 case SAFI_ENCAP:
2625 case SAFI_EVPN:
2626 stream_putc(s, 4);
2627 stream_put(s, &attr->mp_nexthop_global_in, 4);
2628 break;
2629 default:
2630 break;
2631 }
2632 break;
2633 case AFI_IP6:
2634 switch (safi) {
2635 case SAFI_UNICAST:
2636 case SAFI_MULTICAST:
2637 case SAFI_LABELED_UNICAST:
2638 case SAFI_EVPN: {
2639 if (attr->mp_nexthop_len
2640 == BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL) {
2641 stream_putc(s,
2642 BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL);
2643 stream_put(s, &attr->mp_nexthop_global,
2644 IPV6_MAX_BYTELEN);
2645 stream_put(s, &attr->mp_nexthop_local,
2646 IPV6_MAX_BYTELEN);
2647 } else {
2648 stream_putc(s, IPV6_MAX_BYTELEN);
2649 stream_put(s, &attr->mp_nexthop_global,
2650 IPV6_MAX_BYTELEN);
2651 }
2652 } break;
2653 case SAFI_MPLS_VPN: {
2654 if (attr->mp_nexthop_len
2655 == BGP_ATTR_NHLEN_IPV6_GLOBAL) {
2656 stream_putc(s, 24);
2657 stream_putl(s, 0); /* RD = 0, per RFC */
2658 stream_putl(s, 0);
2659 stream_put(s, &attr->mp_nexthop_global,
2660 IPV6_MAX_BYTELEN);
2661 } else if (attr->mp_nexthop_len
2662 == BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL) {
2663 stream_putc(s, 48);
2664 stream_putl(s, 0); /* RD = 0, per RFC */
2665 stream_putl(s, 0);
2666 stream_put(s, &attr->mp_nexthop_global,
2667 IPV6_MAX_BYTELEN);
2668 stream_putl(s, 0); /* RD = 0, per RFC */
2669 stream_putl(s, 0);
2670 stream_put(s, &attr->mp_nexthop_local,
2671 IPV6_MAX_BYTELEN);
2672 }
2673 } break;
2674 case SAFI_ENCAP:
2675 stream_putc(s, IPV6_MAX_BYTELEN);
2676 stream_put(s, &attr->mp_nexthop_global,
2677 IPV6_MAX_BYTELEN);
2678 break;
2679 default:
2680 break;
2681 }
2682 break;
2683 default:
2684 zlog_err(
2685 "Bad nexthop when sening to %s, AFI %u SAFI %u nhlen %d",
2686 peer->host, afi, safi, attr->mp_nexthop_len);
2687 break;
2688 }
2689
2690 /* SNPA */
2691 stream_putc(s, 0);
2692 return sizep;
2693 }
2694
2695 void bgp_packet_mpattr_prefix(struct stream *s, afi_t afi, safi_t safi,
2696 struct prefix *p, struct prefix_rd *prd,
2697 mpls_label_t *label, int addpath_encode,
2698 u_int32_t addpath_tx_id, struct attr *attr)
2699 {
2700 if (safi == SAFI_MPLS_VPN) {
2701 if (addpath_encode)
2702 stream_putl(s, addpath_tx_id);
2703 /* Label, RD, Prefix write. */
2704 stream_putc(s, p->prefixlen + 88);
2705 stream_put(s, label, BGP_LABEL_BYTES);
2706 stream_put(s, prd->val, 8);
2707 stream_put(s, &p->u.prefix, PSIZE(p->prefixlen));
2708 } else if (afi == AFI_L2VPN && safi == SAFI_EVPN) {
2709 /* EVPN prefix - contents depend on type */
2710 bgp_evpn_encode_prefix(s, p, prd, label, attr, addpath_encode,
2711 addpath_tx_id);
2712 } else if (safi == SAFI_LABELED_UNICAST) {
2713 /* Prefix write with label. */
2714 stream_put_labeled_prefix(s, p, label);
2715 } else
2716 stream_put_prefix_addpath(s, p, addpath_encode, addpath_tx_id);
2717 }
2718
2719 size_t bgp_packet_mpattr_prefix_size(afi_t afi, safi_t safi, struct prefix *p)
2720 {
2721 int size = PSIZE(p->prefixlen);
2722 if (safi == SAFI_MPLS_VPN)
2723 size += 88;
2724 else if (afi == AFI_L2VPN && safi == SAFI_EVPN)
2725 size += 232; // TODO: Maximum possible for type-2, type-3 and
2726 // type-5
2727 return size;
2728 }
2729
2730 /*
2731 * Encodes the tunnel encapsulation attribute,
2732 * and with ENABLE_BGP_VNC the VNC attribute which uses
2733 * almost the same TLV format
2734 */
2735 static void bgp_packet_mpattr_tea(struct bgp *bgp, struct peer *peer,
2736 struct stream *s, struct attr *attr,
2737 uint8_t attrtype)
2738 {
2739 unsigned int attrlenfield = 0;
2740 unsigned int attrhdrlen = 0;
2741 struct bgp_attr_encap_subtlv *subtlvs;
2742 struct bgp_attr_encap_subtlv *st;
2743 const char *attrname;
2744
2745 if (!attr || (attrtype == BGP_ATTR_ENCAP
2746 && (!attr->encap_tunneltype
2747 || attr->encap_tunneltype == BGP_ENCAP_TYPE_MPLS)))
2748 return;
2749
2750 switch (attrtype) {
2751 case BGP_ATTR_ENCAP:
2752 attrname = "Tunnel Encap";
2753 subtlvs = attr->encap_subtlvs;
2754 if (subtlvs == NULL) /* nothing to do */
2755 return;
2756 /*
2757 * The tunnel encap attr has an "outer" tlv.
2758 * T = tunneltype,
2759 * L = total length of subtlvs,
2760 * V = concatenated subtlvs.
2761 */
2762 attrlenfield = 2 + 2; /* T + L */
2763 attrhdrlen = 1 + 1; /* subTLV T + L */
2764 break;
2765
2766 #if ENABLE_BGP_VNC
2767 case BGP_ATTR_VNC:
2768 attrname = "VNC";
2769 subtlvs = attr->vnc_subtlvs;
2770 if (subtlvs == NULL) /* nothing to do */
2771 return;
2772 attrlenfield = 0; /* no outer T + L */
2773 attrhdrlen = 2 + 2; /* subTLV T + L */
2774 break;
2775 #endif
2776
2777 default:
2778 assert(0);
2779 }
2780
2781 /* compute attr length */
2782 for (st = subtlvs; st; st = st->next) {
2783 attrlenfield += (attrhdrlen + st->length);
2784 }
2785
2786 if (attrlenfield > 0xffff) {
2787 zlog_info("%s attribute is too long (length=%d), can't send it",
2788 attrname, attrlenfield);
2789 return;
2790 }
2791
2792 if (attrlenfield > 0xff) {
2793 /* 2-octet length field */
2794 stream_putc(s, BGP_ATTR_FLAG_TRANS | BGP_ATTR_FLAG_OPTIONAL
2795 | BGP_ATTR_FLAG_EXTLEN);
2796 stream_putc(s, attrtype);
2797 stream_putw(s, attrlenfield & 0xffff);
2798 } else {
2799 /* 1-octet length field */
2800 stream_putc(s, BGP_ATTR_FLAG_TRANS | BGP_ATTR_FLAG_OPTIONAL);
2801 stream_putc(s, attrtype);
2802 stream_putc(s, attrlenfield & 0xff);
2803 }
2804
2805 if (attrtype == BGP_ATTR_ENCAP) {
2806 /* write outer T+L */
2807 stream_putw(s, attr->encap_tunneltype);
2808 stream_putw(s, attrlenfield - 4);
2809 }
2810
2811 /* write each sub-tlv */
2812 for (st = subtlvs; st; st = st->next) {
2813 if (attrtype == BGP_ATTR_ENCAP) {
2814 stream_putc(s, st->type);
2815 stream_putc(s, st->length);
2816 #if ENABLE_BGP_VNC
2817 } else {
2818 stream_putw(s, st->type);
2819 stream_putw(s, st->length);
2820 #endif
2821 }
2822 stream_put(s, st->value, st->length);
2823 }
2824 }
2825
2826 void bgp_packet_mpattr_end(struct stream *s, size_t sizep)
2827 {
2828 /* Set MP attribute length. Don't count the (2) bytes used to encode
2829 the attr length */
2830 stream_putw_at(s, sizep, (stream_get_endp(s) - sizep) - 2);
2831 }
2832
2833 /* Make attribute packet. */
2834 bgp_size_t bgp_packet_attribute(struct bgp *bgp, struct peer *peer,
2835 struct stream *s, struct attr *attr,
2836 struct bpacket_attr_vec_arr *vecarr,
2837 struct prefix *p, afi_t afi, safi_t safi,
2838 struct peer *from, struct prefix_rd *prd,
2839 mpls_label_t *label, int addpath_encode,
2840 u_int32_t addpath_tx_id)
2841 {
2842 size_t cp;
2843 size_t aspath_sizep;
2844 struct aspath *aspath;
2845 int send_as4_path = 0;
2846 int send_as4_aggregator = 0;
2847 int use32bit = (CHECK_FLAG(peer->cap, PEER_CAP_AS4_RCV)) ? 1 : 0;
2848
2849 if (!bgp)
2850 bgp = peer->bgp;
2851
2852 /* Remember current pointer. */
2853 cp = stream_get_endp(s);
2854
2855 if (p
2856 && !((afi == AFI_IP && safi == SAFI_UNICAST)
2857 && !peer_cap_enhe(peer, afi, safi))) {
2858 size_t mpattrlen_pos = 0;
2859
2860 mpattrlen_pos = bgp_packet_mpattr_start(s, peer, afi, safi,
2861 vecarr, attr);
2862 bgp_packet_mpattr_prefix(s, afi, safi, p, prd, label,
2863 addpath_encode, addpath_tx_id, attr);
2864 bgp_packet_mpattr_end(s, mpattrlen_pos);
2865 }
2866
2867 /* Origin attribute. */
2868 stream_putc(s, BGP_ATTR_FLAG_TRANS);
2869 stream_putc(s, BGP_ATTR_ORIGIN);
2870 stream_putc(s, 1);
2871 stream_putc(s, attr->origin);
2872
2873 /* AS path attribute. */
2874
2875 /* If remote-peer is EBGP */
2876 if (peer->sort == BGP_PEER_EBGP
2877 && (!CHECK_FLAG(peer->af_flags[afi][safi],
2878 PEER_FLAG_AS_PATH_UNCHANGED)
2879 || attr->aspath->segments == NULL)
2880 && (!CHECK_FLAG(peer->af_flags[afi][safi],
2881 PEER_FLAG_RSERVER_CLIENT))) {
2882 aspath = aspath_dup(attr->aspath);
2883
2884 /* Even though we may not be configured for confederations we
2885 * may have
2886 * RXed an AS_PATH with AS_CONFED_SEQUENCE or AS_CONFED_SET */
2887 aspath = aspath_delete_confed_seq(aspath);
2888
2889 if (CHECK_FLAG(bgp->config, BGP_CONFIG_CONFEDERATION)) {
2890 /* Stuff our path CONFED_ID on the front */
2891 aspath = aspath_add_seq(aspath, bgp->confed_id);
2892 } else {
2893 if (peer->change_local_as) {
2894 /* If replace-as is specified, we only use the
2895 change_local_as when
2896 advertising routes. */
2897 if (!CHECK_FLAG(
2898 peer->flags,
2899 PEER_FLAG_LOCAL_AS_REPLACE_AS)) {
2900 aspath = aspath_add_seq(aspath,
2901 peer->local_as);
2902 }
2903 aspath = aspath_add_seq(aspath,
2904 peer->change_local_as);
2905 } else {
2906 aspath = aspath_add_seq(aspath, peer->local_as);
2907 }
2908 }
2909 } else if (peer->sort == BGP_PEER_CONFED) {
2910 /* A confed member, so we need to do the AS_CONFED_SEQUENCE
2911 * thing */
2912 aspath = aspath_dup(attr->aspath);
2913 aspath = aspath_add_confed_seq(aspath, peer->local_as);
2914 } else
2915 aspath = attr->aspath;
2916
2917 /* If peer is not AS4 capable, then:
2918 * - send the created AS_PATH out as AS4_PATH (optional, transitive),
2919 * but ensure that no AS_CONFED_SEQUENCE and AS_CONFED_SET path
2920 * segment
2921 * types are in it (i.e. exclude them if they are there)
2922 * AND do this only if there is at least one asnum > 65535 in the
2923 * path!
2924 * - send an AS_PATH out, but put 16Bit ASnums in it, not 32bit, and
2925 * change
2926 * all ASnums > 65535 to BGP_AS_TRANS
2927 */
2928
2929 stream_putc(s, BGP_ATTR_FLAG_TRANS | BGP_ATTR_FLAG_EXTLEN);
2930 stream_putc(s, BGP_ATTR_AS_PATH);
2931 aspath_sizep = stream_get_endp(s);
2932 stream_putw(s, 0);
2933 stream_putw_at(s, aspath_sizep, aspath_put(s, aspath, use32bit));
2934
2935 /* OLD session may need NEW_AS_PATH sent, if there are 4-byte ASNs
2936 * in the path
2937 */
2938 if (!use32bit && aspath_has_as4(aspath))
2939 send_as4_path =
2940 1; /* we'll do this later, at the correct place */
2941
2942 /* Nexthop attribute. */
2943 if (afi == AFI_IP && safi == SAFI_UNICAST
2944 && !peer_cap_enhe(peer, afi, safi)) {
2945 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_NEXT_HOP)) {
2946 stream_putc(s, BGP_ATTR_FLAG_TRANS);
2947 stream_putc(s, BGP_ATTR_NEXT_HOP);
2948 bpacket_attr_vec_arr_set_vec(vecarr, BGP_ATTR_VEC_NH, s,
2949 attr);
2950 stream_putc(s, 4);
2951 stream_put_ipv4(s, attr->nexthop.s_addr);
2952 } else if (peer_cap_enhe(from, afi, safi)) {
2953 /*
2954 * Likely this is the case when an IPv4 prefix was
2955 * received with
2956 * Extended Next-hop capability and now being advertised
2957 * to
2958 * non-ENHE peers.
2959 * Setting the mandatory (ipv4) next-hop attribute here
2960 * to enable
2961 * implicit next-hop self with correct (ipv4 address
2962 * family).
2963 */
2964 stream_putc(s, BGP_ATTR_FLAG_TRANS);
2965 stream_putc(s, BGP_ATTR_NEXT_HOP);
2966 bpacket_attr_vec_arr_set_vec(vecarr, BGP_ATTR_VEC_NH, s,
2967 NULL);
2968 stream_putc(s, 4);
2969 stream_put_ipv4(s, 0);
2970 }
2971 }
2972
2973 /* MED attribute. */
2974 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_MULTI_EXIT_DISC)
2975 || bgp->maxmed_active) {
2976 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL);
2977 stream_putc(s, BGP_ATTR_MULTI_EXIT_DISC);
2978 stream_putc(s, 4);
2979 stream_putl(s, (bgp->maxmed_active ? bgp->maxmed_value
2980 : attr->med));
2981 }
2982
2983 /* Local preference. */
2984 if (peer->sort == BGP_PEER_IBGP || peer->sort == BGP_PEER_CONFED) {
2985 stream_putc(s, BGP_ATTR_FLAG_TRANS);
2986 stream_putc(s, BGP_ATTR_LOCAL_PREF);
2987 stream_putc(s, 4);
2988 stream_putl(s, attr->local_pref);
2989 }
2990
2991 /* Atomic aggregate. */
2992 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_ATOMIC_AGGREGATE)) {
2993 stream_putc(s, BGP_ATTR_FLAG_TRANS);
2994 stream_putc(s, BGP_ATTR_ATOMIC_AGGREGATE);
2995 stream_putc(s, 0);
2996 }
2997
2998 /* Aggregator. */
2999 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_AGGREGATOR)) {
3000 /* Common to BGP_ATTR_AGGREGATOR, regardless of ASN size */
3001 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS);
3002 stream_putc(s, BGP_ATTR_AGGREGATOR);
3003
3004 if (use32bit) {
3005 /* AS4 capable peer */
3006 stream_putc(s, 8);
3007 stream_putl(s, attr->aggregator_as);
3008 } else {
3009 /* 2-byte AS peer */
3010 stream_putc(s, 6);
3011
3012 /* Is ASN representable in 2-bytes? Or must AS_TRANS be
3013 * used? */
3014 if (attr->aggregator_as > 65535) {
3015 stream_putw(s, BGP_AS_TRANS);
3016
3017 /* we have to send AS4_AGGREGATOR, too.
3018 * we'll do that later in order to send
3019 * attributes in ascending
3020 * order.
3021 */
3022 send_as4_aggregator = 1;
3023 } else
3024 stream_putw(s, (u_int16_t)attr->aggregator_as);
3025 }
3026 stream_put_ipv4(s, attr->aggregator_addr.s_addr);
3027 }
3028
3029 /* Community attribute. */
3030 if (CHECK_FLAG(peer->af_flags[afi][safi], PEER_FLAG_SEND_COMMUNITY)
3031 && (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_COMMUNITIES))) {
3032 if (attr->community->size * 4 > 255) {
3033 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL
3034 | BGP_ATTR_FLAG_TRANS
3035 | BGP_ATTR_FLAG_EXTLEN);
3036 stream_putc(s, BGP_ATTR_COMMUNITIES);
3037 stream_putw(s, attr->community->size * 4);
3038 } else {
3039 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL
3040 | BGP_ATTR_FLAG_TRANS);
3041 stream_putc(s, BGP_ATTR_COMMUNITIES);
3042 stream_putc(s, attr->community->size * 4);
3043 }
3044 stream_put(s, attr->community->val, attr->community->size * 4);
3045 }
3046
3047 /*
3048 * Large Community attribute.
3049 */
3050 if (CHECK_FLAG(peer->af_flags[afi][safi],
3051 PEER_FLAG_SEND_LARGE_COMMUNITY)
3052 && (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_LARGE_COMMUNITIES))) {
3053 if (lcom_length(attr->lcommunity) > 255) {
3054 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL
3055 | BGP_ATTR_FLAG_TRANS
3056 | BGP_ATTR_FLAG_EXTLEN);
3057 stream_putc(s, BGP_ATTR_LARGE_COMMUNITIES);
3058 stream_putw(s, lcom_length(attr->lcommunity));
3059 } else {
3060 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL
3061 | BGP_ATTR_FLAG_TRANS);
3062 stream_putc(s, BGP_ATTR_LARGE_COMMUNITIES);
3063 stream_putc(s, lcom_length(attr->lcommunity));
3064 }
3065 stream_put(s, attr->lcommunity->val,
3066 lcom_length(attr->lcommunity));
3067 }
3068
3069 /* Route Reflector. */
3070 if (peer->sort == BGP_PEER_IBGP && from
3071 && from->sort == BGP_PEER_IBGP) {
3072 /* Originator ID. */
3073 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL);
3074 stream_putc(s, BGP_ATTR_ORIGINATOR_ID);
3075 stream_putc(s, 4);
3076
3077 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_ORIGINATOR_ID))
3078 stream_put_in_addr(s, &attr->originator_id);
3079 else
3080 stream_put_in_addr(s, &from->remote_id);
3081
3082 /* Cluster list. */
3083 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL);
3084 stream_putc(s, BGP_ATTR_CLUSTER_LIST);
3085
3086 if (attr->cluster) {
3087 stream_putc(s, attr->cluster->length + 4);
3088 /* If this peer configuration's parent BGP has
3089 * cluster_id. */
3090 if (bgp->config & BGP_CONFIG_CLUSTER_ID)
3091 stream_put_in_addr(s, &bgp->cluster_id);
3092 else
3093 stream_put_in_addr(s, &bgp->router_id);
3094 stream_put(s, attr->cluster->list,
3095 attr->cluster->length);
3096 } else {
3097 stream_putc(s, 4);
3098 /* If this peer configuration's parent BGP has
3099 * cluster_id. */
3100 if (bgp->config & BGP_CONFIG_CLUSTER_ID)
3101 stream_put_in_addr(s, &bgp->cluster_id);
3102 else
3103 stream_put_in_addr(s, &bgp->router_id);
3104 }
3105 }
3106
3107 /* Extended Communities attribute. */
3108 if (CHECK_FLAG(peer->af_flags[afi][safi], PEER_FLAG_SEND_EXT_COMMUNITY)
3109 && (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_EXT_COMMUNITIES))) {
3110 if (peer->sort == BGP_PEER_IBGP
3111 || peer->sort == BGP_PEER_CONFED) {
3112 if (attr->ecommunity->size * 8 > 255) {
3113 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL
3114 | BGP_ATTR_FLAG_TRANS
3115 | BGP_ATTR_FLAG_EXTLEN);
3116 stream_putc(s, BGP_ATTR_EXT_COMMUNITIES);
3117 stream_putw(s, attr->ecommunity->size * 8);
3118 } else {
3119 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL
3120 | BGP_ATTR_FLAG_TRANS);
3121 stream_putc(s, BGP_ATTR_EXT_COMMUNITIES);
3122 stream_putc(s, attr->ecommunity->size * 8);
3123 }
3124 stream_put(s, attr->ecommunity->val,
3125 attr->ecommunity->size * 8);
3126 } else {
3127 u_int8_t *pnt;
3128 int tbit;
3129 int ecom_tr_size = 0;
3130 int i;
3131
3132 for (i = 0; i < attr->ecommunity->size; i++) {
3133 pnt = attr->ecommunity->val + (i * 8);
3134 tbit = *pnt;
3135
3136 if (CHECK_FLAG(tbit,
3137 ECOMMUNITY_FLAG_NON_TRANSITIVE))
3138 continue;
3139
3140 ecom_tr_size++;
3141 }
3142
3143 if (ecom_tr_size) {
3144 if (ecom_tr_size * 8 > 255) {
3145 stream_putc(
3146 s,
3147 BGP_ATTR_FLAG_OPTIONAL
3148 | BGP_ATTR_FLAG_TRANS
3149 | BGP_ATTR_FLAG_EXTLEN);
3150 stream_putc(s,
3151 BGP_ATTR_EXT_COMMUNITIES);
3152 stream_putw(s, ecom_tr_size * 8);
3153 } else {
3154 stream_putc(
3155 s,
3156 BGP_ATTR_FLAG_OPTIONAL
3157 | BGP_ATTR_FLAG_TRANS);
3158 stream_putc(s,
3159 BGP_ATTR_EXT_COMMUNITIES);
3160 stream_putc(s, ecom_tr_size * 8);
3161 }
3162
3163 for (i = 0; i < attr->ecommunity->size; i++) {
3164 pnt = attr->ecommunity->val + (i * 8);
3165 tbit = *pnt;
3166
3167 if (CHECK_FLAG(
3168 tbit,
3169 ECOMMUNITY_FLAG_NON_TRANSITIVE))
3170 continue;
3171
3172 stream_put(s, pnt, 8);
3173 }
3174 }
3175 }
3176 }
3177
3178 /* Label index attribute. */
3179 if (safi == SAFI_LABELED_UNICAST) {
3180 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_PREFIX_SID)) {
3181 u_int32_t label_index;
3182
3183 label_index = attr->label_index;
3184
3185 if (label_index != BGP_INVALID_LABEL_INDEX) {
3186 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL
3187 | BGP_ATTR_FLAG_TRANS);
3188 stream_putc(s, BGP_ATTR_PREFIX_SID);
3189 stream_putc(s, 10);
3190 stream_putc(s, BGP_PREFIX_SID_LABEL_INDEX);
3191 stream_putw(s,
3192 BGP_PREFIX_SID_LABEL_INDEX_LENGTH);
3193 stream_putc(s, 0); // reserved
3194 stream_putw(s, 0); // flags
3195 stream_putl(s, label_index);
3196 }
3197 }
3198 }
3199
3200 if (send_as4_path) {
3201 /* If the peer is NOT As4 capable, AND */
3202 /* there are ASnums > 65535 in path THEN
3203 * give out AS4_PATH */
3204
3205 /* Get rid of all AS_CONFED_SEQUENCE and AS_CONFED_SET
3206 * path segments!
3207 * Hm, I wonder... confederation things *should* only be at
3208 * the beginning of an aspath, right? Then we should use
3209 * aspath_delete_confed_seq for this, because it is already
3210 * there! (JK)
3211 * Folks, talk to me: what is reasonable here!?
3212 */
3213 aspath = aspath_delete_confed_seq(aspath);
3214
3215 stream_putc(s, BGP_ATTR_FLAG_TRANS | BGP_ATTR_FLAG_OPTIONAL
3216 | BGP_ATTR_FLAG_EXTLEN);
3217 stream_putc(s, BGP_ATTR_AS4_PATH);
3218 aspath_sizep = stream_get_endp(s);
3219 stream_putw(s, 0);
3220 stream_putw_at(s, aspath_sizep, aspath_put(s, aspath, 1));
3221 }
3222
3223 if (aspath != attr->aspath)
3224 aspath_free(aspath);
3225
3226 if (send_as4_aggregator) {
3227 /* send AS4_AGGREGATOR, at this place */
3228 /* this section of code moved here in order to ensure the
3229 * correct
3230 * *ascending* order of attributes
3231 */
3232 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS);
3233 stream_putc(s, BGP_ATTR_AS4_AGGREGATOR);
3234 stream_putc(s, 8);
3235 stream_putl(s, attr->aggregator_as);
3236 stream_put_ipv4(s, attr->aggregator_addr.s_addr);
3237 }
3238
3239 if (((afi == AFI_IP || afi == AFI_IP6)
3240 && (safi == SAFI_ENCAP || safi == SAFI_MPLS_VPN))
3241 || (afi == AFI_L2VPN && safi == SAFI_EVPN)) {
3242 /* Tunnel Encap attribute */
3243 bgp_packet_mpattr_tea(bgp, peer, s, attr, BGP_ATTR_ENCAP);
3244
3245 #if ENABLE_BGP_VNC
3246 /* VNC attribute */
3247 bgp_packet_mpattr_tea(bgp, peer, s, attr, BGP_ATTR_VNC);
3248 #endif
3249 }
3250
3251 /* Unknown transit attribute. */
3252 if (attr->transit)
3253 stream_put(s, attr->transit->val, attr->transit->length);
3254
3255 /* Return total size of attribute. */
3256 return stream_get_endp(s) - cp;
3257 }
3258
3259 size_t bgp_packet_mpunreach_start(struct stream *s, afi_t afi, safi_t safi)
3260 {
3261 unsigned long attrlen_pnt;
3262 iana_afi_t pkt_afi;
3263 iana_safi_t pkt_safi;
3264
3265 /* Set extended bit always to encode the attribute length as 2 bytes */
3266 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_EXTLEN);
3267 stream_putc(s, BGP_ATTR_MP_UNREACH_NLRI);
3268
3269 attrlen_pnt = stream_get_endp(s);
3270 stream_putw(s, 0); /* Length of this attribute. */
3271
3272 /* Convert AFI, SAFI to values for packet. */
3273 bgp_map_afi_safi_int2iana(afi, safi, &pkt_afi, &pkt_safi);
3274
3275 stream_putw(s, pkt_afi);
3276 stream_putc(s, pkt_safi);
3277
3278 return attrlen_pnt;
3279 }
3280
3281 void bgp_packet_mpunreach_prefix(struct stream *s, struct prefix *p, afi_t afi,
3282 safi_t safi, struct prefix_rd *prd,
3283 mpls_label_t *label, int addpath_encode,
3284 u_int32_t addpath_tx_id, struct attr *attr)
3285 {
3286 u_char wlabel[3] = {0x80, 0x00, 0x00};
3287
3288 if (safi == SAFI_LABELED_UNICAST)
3289 label = (mpls_label_t *)wlabel;
3290
3291 return bgp_packet_mpattr_prefix(s, afi, safi, p, prd, label,
3292 addpath_encode, addpath_tx_id, attr);
3293 }
3294
3295 void bgp_packet_mpunreach_end(struct stream *s, size_t attrlen_pnt)
3296 {
3297 bgp_packet_mpattr_end(s, attrlen_pnt);
3298 }
3299
3300 /* Initialization of attribute. */
3301 void bgp_attr_init(void)
3302 {
3303 aspath_init();
3304 attrhash_init();
3305 community_init();
3306 ecommunity_init();
3307 lcommunity_init();
3308 cluster_init();
3309 transit_init();
3310 encap_init();
3311 }
3312
3313 void bgp_attr_finish(void)
3314 {
3315 aspath_finish();
3316 attrhash_finish();
3317 community_finish();
3318 ecommunity_finish();
3319 lcommunity_finish();
3320 cluster_finish();
3321 transit_finish();
3322 encap_finish();
3323 }
3324
3325 /* Make attribute packet. */
3326 void bgp_dump_routes_attr(struct stream *s, struct attr *attr,
3327 struct prefix *prefix)
3328 {
3329 unsigned long cp;
3330 unsigned long len;
3331 size_t aspath_lenp;
3332 struct aspath *aspath;
3333 int addpath_encode = 0;
3334 u_int32_t addpath_tx_id = 0;
3335
3336 /* Remember current pointer. */
3337 cp = stream_get_endp(s);
3338
3339 /* Place holder of length. */
3340 stream_putw(s, 0);
3341
3342 /* Origin attribute. */
3343 stream_putc(s, BGP_ATTR_FLAG_TRANS);
3344 stream_putc(s, BGP_ATTR_ORIGIN);
3345 stream_putc(s, 1);
3346 stream_putc(s, attr->origin);
3347
3348 aspath = attr->aspath;
3349
3350 stream_putc(s, BGP_ATTR_FLAG_TRANS | BGP_ATTR_FLAG_EXTLEN);
3351 stream_putc(s, BGP_ATTR_AS_PATH);
3352 aspath_lenp = stream_get_endp(s);
3353 stream_putw(s, 0);
3354
3355 stream_putw_at(s, aspath_lenp, aspath_put(s, aspath, 1));
3356
3357 /* Nexthop attribute. */
3358 /* If it's an IPv6 prefix, don't dump the IPv4 nexthop to save space */
3359 if (prefix != NULL && prefix->family != AF_INET6) {
3360 stream_putc(s, BGP_ATTR_FLAG_TRANS);
3361 stream_putc(s, BGP_ATTR_NEXT_HOP);
3362 stream_putc(s, 4);
3363 stream_put_ipv4(s, attr->nexthop.s_addr);
3364 }
3365
3366 /* MED attribute. */
3367 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_MULTI_EXIT_DISC)) {
3368 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL);
3369 stream_putc(s, BGP_ATTR_MULTI_EXIT_DISC);
3370 stream_putc(s, 4);
3371 stream_putl(s, attr->med);
3372 }
3373
3374 /* Local preference. */
3375 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_LOCAL_PREF)) {
3376 stream_putc(s, BGP_ATTR_FLAG_TRANS);
3377 stream_putc(s, BGP_ATTR_LOCAL_PREF);
3378 stream_putc(s, 4);
3379 stream_putl(s, attr->local_pref);
3380 }
3381
3382 /* Atomic aggregate. */
3383 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_ATOMIC_AGGREGATE)) {
3384 stream_putc(s, BGP_ATTR_FLAG_TRANS);
3385 stream_putc(s, BGP_ATTR_ATOMIC_AGGREGATE);
3386 stream_putc(s, 0);
3387 }
3388
3389 /* Aggregator. */
3390 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_AGGREGATOR)) {
3391 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS);
3392 stream_putc(s, BGP_ATTR_AGGREGATOR);
3393 stream_putc(s, 8);
3394 stream_putl(s, attr->aggregator_as);
3395 stream_put_ipv4(s, attr->aggregator_addr.s_addr);
3396 }
3397
3398 /* Community attribute. */
3399 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_COMMUNITIES)) {
3400 if (attr->community->size * 4 > 255) {
3401 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL
3402 | BGP_ATTR_FLAG_TRANS
3403 | BGP_ATTR_FLAG_EXTLEN);
3404 stream_putc(s, BGP_ATTR_COMMUNITIES);
3405 stream_putw(s, attr->community->size * 4);
3406 } else {
3407 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL
3408 | BGP_ATTR_FLAG_TRANS);
3409 stream_putc(s, BGP_ATTR_COMMUNITIES);
3410 stream_putc(s, attr->community->size * 4);
3411 }
3412 stream_put(s, attr->community->val, attr->community->size * 4);
3413 }
3414
3415 /* Large Community attribute. */
3416 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_LARGE_COMMUNITIES)) {
3417 if (lcom_length(attr->lcommunity) > 255) {
3418 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL
3419 | BGP_ATTR_FLAG_TRANS
3420 | BGP_ATTR_FLAG_EXTLEN);
3421 stream_putc(s, BGP_ATTR_LARGE_COMMUNITIES);
3422 stream_putw(s, lcom_length(attr->lcommunity));
3423 } else {
3424 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL
3425 | BGP_ATTR_FLAG_TRANS);
3426 stream_putc(s, BGP_ATTR_LARGE_COMMUNITIES);
3427 stream_putc(s, lcom_length(attr->lcommunity));
3428 }
3429
3430 stream_put(s, attr->lcommunity->val, lcom_length(attr->lcommunity));
3431 }
3432
3433 /* Add a MP_NLRI attribute to dump the IPv6 next hop */
3434 if (prefix != NULL && prefix->family == AF_INET6
3435 && (attr->mp_nexthop_len == BGP_ATTR_NHLEN_IPV6_GLOBAL
3436 || attr->mp_nexthop_len == BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL)) {
3437 int sizep;
3438
3439 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL);
3440 stream_putc(s, BGP_ATTR_MP_REACH_NLRI);
3441 sizep = stream_get_endp(s);
3442
3443 /* MP header */
3444 stream_putc(s, 0); /* Marker: Attribute length. */
3445 stream_putw(s, AFI_IP6); /* AFI */
3446 stream_putc(s, SAFI_UNICAST); /* SAFI */
3447
3448 /* Next hop */
3449 stream_putc(s, attr->mp_nexthop_len);
3450 stream_put(s, &attr->mp_nexthop_global, IPV6_MAX_BYTELEN);
3451 if (attr->mp_nexthop_len == BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL)
3452 stream_put(s, &attr->mp_nexthop_local,
3453 IPV6_MAX_BYTELEN);
3454
3455 /* SNPA */
3456 stream_putc(s, 0);
3457
3458 /* Prefix */
3459 stream_put_prefix_addpath(s, prefix, addpath_encode,
3460 addpath_tx_id);
3461
3462 /* Set MP attribute length. */
3463 stream_putc_at(s, sizep, (stream_get_endp(s) - sizep) - 1);
3464 }
3465
3466 /* Prefix SID */
3467 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_PREFIX_SID)) {
3468 if (attr->label_index != BGP_INVALID_LABEL_INDEX) {
3469 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL
3470 | BGP_ATTR_FLAG_TRANS);
3471 stream_putc(s, BGP_ATTR_PREFIX_SID);
3472 stream_putc(s, 10);
3473 stream_putc(s, BGP_PREFIX_SID_LABEL_INDEX);
3474 stream_putc(s, BGP_PREFIX_SID_LABEL_INDEX_LENGTH);
3475 stream_putc(s, 0); // reserved
3476 stream_putw(s, 0); // flags
3477 stream_putl(s, attr->label_index);
3478 }
3479 }
3480
3481 /* Return total size of attribute. */
3482 len = stream_get_endp(s) - cp - 2;
3483 stream_putw_at(s, cp, len);
3484 }
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