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Merge pull request #2475 from LabNConsulting/working/master/no_vrf_socket_4l3mdev
[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 #include "bgp_flowspec_private.h"
56
57 /* Attribute strings for logging. */
58 static const struct message attr_str[] = {
59 {BGP_ATTR_ORIGIN, "ORIGIN"},
60 {BGP_ATTR_AS_PATH, "AS_PATH"},
61 {BGP_ATTR_NEXT_HOP, "NEXT_HOP"},
62 {BGP_ATTR_MULTI_EXIT_DISC, "MULTI_EXIT_DISC"},
63 {BGP_ATTR_LOCAL_PREF, "LOCAL_PREF"},
64 {BGP_ATTR_ATOMIC_AGGREGATE, "ATOMIC_AGGREGATE"},
65 {BGP_ATTR_AGGREGATOR, "AGGREGATOR"},
66 {BGP_ATTR_COMMUNITIES, "COMMUNITY"},
67 {BGP_ATTR_ORIGINATOR_ID, "ORIGINATOR_ID"},
68 {BGP_ATTR_CLUSTER_LIST, "CLUSTER_LIST"},
69 {BGP_ATTR_DPA, "DPA"},
70 {BGP_ATTR_ADVERTISER, "ADVERTISER"},
71 {BGP_ATTR_RCID_PATH, "RCID_PATH"},
72 {BGP_ATTR_MP_REACH_NLRI, "MP_REACH_NLRI"},
73 {BGP_ATTR_MP_UNREACH_NLRI, "MP_UNREACH_NLRI"},
74 {BGP_ATTR_EXT_COMMUNITIES, "EXT_COMMUNITIES"},
75 {BGP_ATTR_AS4_PATH, "AS4_PATH"},
76 {BGP_ATTR_AS4_AGGREGATOR, "AS4_AGGREGATOR"},
77 {BGP_ATTR_AS_PATHLIMIT, "AS_PATHLIMIT"},
78 {BGP_ATTR_PMSI_TUNNEL, "PMSI_TUNNEL_ATTRIBUTE"},
79 {BGP_ATTR_ENCAP, "ENCAP"},
80 #if ENABLE_BGP_VNC
81 {BGP_ATTR_VNC, "VNC"},
82 #endif
83 {BGP_ATTR_LARGE_COMMUNITIES, "LARGE_COMMUNITY"},
84 {BGP_ATTR_PREFIX_SID, "PREFIX_SID"},
85 {0}};
86
87 static const struct message attr_flag_str[] = {
88 {BGP_ATTR_FLAG_OPTIONAL, "Optional"},
89 {BGP_ATTR_FLAG_TRANS, "Transitive"},
90 {BGP_ATTR_FLAG_PARTIAL, "Partial"},
91 /* bgp_attr_flags_diagnose() relies on this bit being last in
92 this list */
93 {BGP_ATTR_FLAG_EXTLEN, "Extended Length"},
94 {0}};
95
96 static struct hash *cluster_hash;
97
98 static void *cluster_hash_alloc(void *p)
99 {
100 const struct cluster_list *val = (const struct cluster_list *)p;
101 struct cluster_list *cluster;
102
103 cluster = XMALLOC(MTYPE_CLUSTER, sizeof(struct cluster_list));
104 cluster->length = val->length;
105
106 if (cluster->length) {
107 cluster->list = XMALLOC(MTYPE_CLUSTER_VAL, val->length);
108 memcpy(cluster->list, val->list, val->length);
109 } else
110 cluster->list = NULL;
111
112 cluster->refcnt = 0;
113
114 return cluster;
115 }
116
117 /* Cluster list related functions. */
118 static struct cluster_list *cluster_parse(struct in_addr *pnt, int length)
119 {
120 struct cluster_list tmp;
121 struct cluster_list *cluster;
122
123 tmp.length = length;
124 tmp.list = pnt;
125
126 cluster = hash_get(cluster_hash, &tmp, cluster_hash_alloc);
127 cluster->refcnt++;
128 return cluster;
129 }
130
131 int cluster_loop_check(struct cluster_list *cluster, struct in_addr originator)
132 {
133 int i;
134
135 for (i = 0; i < cluster->length / 4; i++)
136 if (cluster->list[i].s_addr == originator.s_addr)
137 return 1;
138 return 0;
139 }
140
141 static unsigned int cluster_hash_key_make(void *p)
142 {
143 const struct cluster_list *cluster = p;
144
145 return jhash(cluster->list, cluster->length, 0);
146 }
147
148 static int cluster_hash_cmp(const void *p1, const void *p2)
149 {
150 const struct cluster_list *cluster1 = p1;
151 const struct cluster_list *cluster2 = p2;
152
153 return (cluster1->length == cluster2->length
154 && memcmp(cluster1->list, cluster2->list, cluster1->length)
155 == 0);
156 }
157
158 static void cluster_free(struct cluster_list *cluster)
159 {
160 if (cluster->list)
161 XFREE(MTYPE_CLUSTER_VAL, cluster->list);
162 XFREE(MTYPE_CLUSTER, cluster);
163 }
164
165 static struct cluster_list *cluster_intern(struct cluster_list *cluster)
166 {
167 struct cluster_list *find;
168
169 find = hash_get(cluster_hash, cluster, cluster_hash_alloc);
170 find->refcnt++;
171
172 return find;
173 }
174
175 void cluster_unintern(struct cluster_list *cluster)
176 {
177 if (cluster->refcnt)
178 cluster->refcnt--;
179
180 if (cluster->refcnt == 0) {
181 hash_release(cluster_hash, cluster);
182 cluster_free(cluster);
183 }
184 }
185
186 static void cluster_init(void)
187 {
188 cluster_hash = hash_create(cluster_hash_key_make, 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, encap_hash_cmp,
366 "BGP Encap Hash");
367 #if ENABLE_BGP_VNC
368 vnc_hash = hash_create(encap_hash_key_make, encap_hash_cmp,
369 "BGP VNC Hash");
370 #endif
371 }
372
373 static void encap_finish(void)
374 {
375 hash_clean(encap_hash, (void (*)(void *))encap_free);
376 hash_free(encap_hash);
377 encap_hash = NULL;
378 #if ENABLE_BGP_VNC
379 hash_clean(vnc_hash, (void (*)(void *))encap_free);
380 hash_free(vnc_hash);
381 vnc_hash = NULL;
382 #endif
383 }
384
385 static bool overlay_index_same(const struct attr *a1, const struct attr *a2)
386 {
387 if (!a1 && a2)
388 return false;
389 if (!a2 && a1)
390 return false;
391 if (!a1 && !a2)
392 return true;
393 return !memcmp(&(a1->evpn_overlay), &(a2->evpn_overlay),
394 sizeof(struct overlay_index));
395 }
396
397 /* Unknown transit attribute. */
398 static struct hash *transit_hash;
399
400 static void transit_free(struct transit *transit)
401 {
402 if (transit->val)
403 XFREE(MTYPE_TRANSIT_VAL, transit->val);
404 XFREE(MTYPE_TRANSIT, transit);
405 }
406
407 static void *transit_hash_alloc(void *p)
408 {
409 /* Transit structure is already allocated. */
410 return p;
411 }
412
413 static struct transit *transit_intern(struct transit *transit)
414 {
415 struct transit *find;
416
417 find = hash_get(transit_hash, transit, transit_hash_alloc);
418 if (find != transit)
419 transit_free(transit);
420 find->refcnt++;
421
422 return find;
423 }
424
425 void transit_unintern(struct transit *transit)
426 {
427 if (transit->refcnt)
428 transit->refcnt--;
429
430 if (transit->refcnt == 0) {
431 hash_release(transit_hash, transit);
432 transit_free(transit);
433 }
434 }
435
436 static unsigned int transit_hash_key_make(void *p)
437 {
438 const struct transit *transit = p;
439
440 return jhash(transit->val, transit->length, 0);
441 }
442
443 static int transit_hash_cmp(const void *p1, const void *p2)
444 {
445 const struct transit *transit1 = p1;
446 const struct transit *transit2 = p2;
447
448 return (transit1->length == transit2->length
449 && memcmp(transit1->val, transit2->val, transit1->length) == 0);
450 }
451
452 static void transit_init(void)
453 {
454 transit_hash = hash_create(transit_hash_key_make, transit_hash_cmp,
455 "BGP Transit Hash");
456 }
457
458 static void transit_finish(void)
459 {
460 hash_clean(transit_hash, (void (*)(void *))transit_free);
461 hash_free(transit_hash);
462 transit_hash = NULL;
463 }
464
465 /* Attribute hash routines. */
466 static struct hash *attrhash;
467
468 /* Shallow copy of an attribute
469 * Though, not so shallow that it doesn't copy the contents
470 * of the attr_extra pointed to by 'extra'
471 */
472 void bgp_attr_dup(struct attr *new, struct attr *orig)
473 {
474 *new = *orig;
475 }
476
477 unsigned long int attr_count(void)
478 {
479 return attrhash->count;
480 }
481
482 unsigned long int attr_unknown_count(void)
483 {
484 return transit_hash->count;
485 }
486
487 unsigned int attrhash_key_make(void *p)
488 {
489 const struct attr *attr = (struct attr *)p;
490 uint32_t key = 0;
491 #define MIX(val) key = jhash_1word(val, key)
492 #define MIX3(a, b, c) key = jhash_3words((a), (b), (c), key)
493
494 MIX3(attr->origin, attr->nexthop.s_addr, attr->med);
495 MIX3(attr->local_pref, attr->aggregator_as,
496 attr->aggregator_addr.s_addr);
497 MIX3(attr->weight, attr->mp_nexthop_global_in.s_addr,
498 attr->originator_id.s_addr);
499 MIX3(attr->tag, attr->label, attr->label_index);
500
501 if (attr->aspath)
502 MIX(aspath_key_make(attr->aspath));
503 if (attr->community)
504 MIX(community_hash_make(attr->community));
505
506 if (attr->lcommunity)
507 MIX(lcommunity_hash_make(attr->lcommunity));
508 if (attr->ecommunity)
509 MIX(ecommunity_hash_make(attr->ecommunity));
510 if (attr->cluster)
511 MIX(cluster_hash_key_make(attr->cluster));
512 if (attr->transit)
513 MIX(transit_hash_key_make(attr->transit));
514 if (attr->encap_subtlvs)
515 MIX(encap_hash_key_make(attr->encap_subtlvs));
516 #if ENABLE_BGP_VNC
517 if (attr->vnc_subtlvs)
518 MIX(encap_hash_key_make(attr->vnc_subtlvs));
519 #endif
520 MIX(attr->mp_nexthop_len);
521 key = jhash(attr->mp_nexthop_global.s6_addr, IPV6_MAX_BYTELEN, key);
522 key = jhash(attr->mp_nexthop_local.s6_addr, IPV6_MAX_BYTELEN, key);
523 MIX(attr->nh_ifindex);
524 MIX(attr->nh_lla_ifindex);
525
526 return key;
527 }
528
529 int attrhash_cmp(const void *p1, const void *p2)
530 {
531 const struct attr *attr1 = p1;
532 const struct attr *attr2 = p2;
533
534 if (attr1->flag == attr2->flag && attr1->origin == attr2->origin
535 && attr1->nexthop.s_addr == attr2->nexthop.s_addr
536 && attr1->aspath == attr2->aspath
537 && attr1->community == attr2->community && attr1->med == attr2->med
538 && attr1->local_pref == attr2->local_pref
539 && attr1->rmap_change_flags == attr2->rmap_change_flags) {
540 if (attr1->aggregator_as == attr2->aggregator_as
541 && attr1->aggregator_addr.s_addr
542 == attr2->aggregator_addr.s_addr
543 && attr1->weight == attr2->weight
544 && attr1->tag == attr2->tag
545 && attr1->label_index == attr2->label_index
546 && attr1->mp_nexthop_len == attr2->mp_nexthop_len
547 && attr1->ecommunity == attr2->ecommunity
548 && attr1->lcommunity == attr2->lcommunity
549 && attr1->cluster == attr2->cluster
550 && attr1->transit == attr2->transit
551 && (attr1->encap_tunneltype == attr2->encap_tunneltype)
552 && encap_same(attr1->encap_subtlvs, attr2->encap_subtlvs)
553 #if ENABLE_BGP_VNC
554 && encap_same(attr1->vnc_subtlvs, attr2->vnc_subtlvs)
555 #endif
556 && IPV6_ADDR_SAME(&attr1->mp_nexthop_global,
557 &attr2->mp_nexthop_global)
558 && IPV6_ADDR_SAME(&attr1->mp_nexthop_local,
559 &attr2->mp_nexthop_local)
560 && IPV4_ADDR_SAME(&attr1->mp_nexthop_global_in,
561 &attr2->mp_nexthop_global_in)
562 && IPV4_ADDR_SAME(&attr1->originator_id,
563 &attr2->originator_id)
564 && overlay_index_same(attr1, attr2)
565 && attr1->nh_ifindex == attr2->nh_ifindex
566 && attr1->nh_lla_ifindex == attr2->nh_lla_ifindex)
567 return 1;
568 }
569
570 return 0;
571 }
572
573 static void attrhash_init(void)
574 {
575 attrhash =
576 hash_create(attrhash_key_make, attrhash_cmp, "BGP Attributes");
577 }
578
579 /*
580 * special for hash_clean below
581 */
582 static void attr_vfree(void *attr)
583 {
584 XFREE(MTYPE_ATTR, attr);
585 }
586
587 static void attrhash_finish(void)
588 {
589 hash_clean(attrhash, attr_vfree);
590 hash_free(attrhash);
591 attrhash = NULL;
592 }
593
594 static void attr_show_all_iterator(struct hash_backet *backet, struct vty *vty)
595 {
596 struct attr *attr = backet->data;
597
598 vty_out(vty, "attr[%ld] nexthop %s\n", attr->refcnt,
599 inet_ntoa(attr->nexthop));
600 vty_out(vty, "\tflags: %" PRIu64 " med: %u local_pref: %u origin: %u weight: %u label: %u\n",
601 attr->flag, attr->med, attr->local_pref, attr->origin,
602 attr->weight, attr->label);
603 }
604
605 void attr_show_all(struct vty *vty)
606 {
607 hash_iterate(attrhash, (void (*)(struct hash_backet *,
608 void *))attr_show_all_iterator,
609 vty);
610 }
611
612 static void *bgp_attr_hash_alloc(void *p)
613 {
614 struct attr *val = (struct attr *)p;
615 struct attr *attr;
616
617 attr = XMALLOC(MTYPE_ATTR, sizeof(struct attr));
618 *attr = *val;
619 if (val->encap_subtlvs) {
620 val->encap_subtlvs = NULL;
621 }
622 #if ENABLE_BGP_VNC
623 if (val->vnc_subtlvs) {
624 val->vnc_subtlvs = NULL;
625 }
626 #endif
627 attr->refcnt = 0;
628 return attr;
629 }
630
631 /* Internet argument attribute. */
632 struct attr *bgp_attr_intern(struct attr *attr)
633 {
634 struct attr *find;
635
636 /* Intern referenced strucutre. */
637 if (attr->aspath) {
638 if (!attr->aspath->refcnt)
639 attr->aspath = aspath_intern(attr->aspath);
640 else
641 attr->aspath->refcnt++;
642 }
643 if (attr->community) {
644 if (!attr->community->refcnt)
645 attr->community = community_intern(attr->community);
646 else
647 attr->community->refcnt++;
648 }
649
650 if (attr->ecommunity) {
651 if (!attr->ecommunity->refcnt)
652 attr->ecommunity = ecommunity_intern(attr->ecommunity);
653 else
654 attr->ecommunity->refcnt++;
655 }
656 if (attr->lcommunity) {
657 if (!attr->lcommunity->refcnt)
658 attr->lcommunity = lcommunity_intern(attr->lcommunity);
659 else
660 attr->lcommunity->refcnt++;
661 }
662 if (attr->cluster) {
663 if (!attr->cluster->refcnt)
664 attr->cluster = cluster_intern(attr->cluster);
665 else
666 attr->cluster->refcnt++;
667 }
668 if (attr->transit) {
669 if (!attr->transit->refcnt)
670 attr->transit = transit_intern(attr->transit);
671 else
672 attr->transit->refcnt++;
673 }
674 if (attr->encap_subtlvs) {
675 if (!attr->encap_subtlvs->refcnt)
676 attr->encap_subtlvs = encap_intern(attr->encap_subtlvs,
677 ENCAP_SUBTLV_TYPE);
678 else
679 attr->encap_subtlvs->refcnt++;
680 }
681 #if ENABLE_BGP_VNC
682 if (attr->vnc_subtlvs) {
683 if (!attr->vnc_subtlvs->refcnt)
684 attr->vnc_subtlvs = encap_intern(attr->vnc_subtlvs,
685 VNC_SUBTLV_TYPE);
686 else
687 attr->vnc_subtlvs->refcnt++;
688 }
689 #endif
690
691 /* At this point, attr only contains intern'd pointers. that means
692 * if we find it in attrhash, it has all the same pointers and we
693 * correctly updated the refcounts on these.
694 * If we don't find it, we need to allocate a one because in all
695 * cases this returns a new reference to a hashed attr, but the input
696 * wasn't on hash. */
697 find = (struct attr *)hash_get(attrhash, attr, bgp_attr_hash_alloc);
698 find->refcnt++;
699
700 return find;
701 }
702
703 /* Make network statement's attribute. */
704 struct attr *bgp_attr_default_set(struct attr *attr, uint8_t origin)
705 {
706 memset(attr, 0, sizeof(struct attr));
707
708 attr->origin = origin;
709 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_ORIGIN);
710 attr->aspath = aspath_empty();
711 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_AS_PATH);
712 attr->weight = BGP_ATTR_DEFAULT_WEIGHT;
713 attr->tag = 0;
714 attr->label_index = BGP_INVALID_LABEL_INDEX;
715 attr->label = MPLS_INVALID_LABEL;
716 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_NEXT_HOP);
717 attr->mp_nexthop_len = IPV6_MAX_BYTELEN;
718
719 return attr;
720 }
721
722 /* Create the attributes for an aggregate */
723 struct attr *bgp_attr_aggregate_intern(struct bgp *bgp, uint8_t origin,
724 struct aspath *aspath,
725 struct community *community, int as_set,
726 uint8_t atomic_aggregate)
727 {
728 struct attr attr;
729 struct attr *new;
730
731 memset(&attr, 0, sizeof(struct attr));
732
733 /* Origin attribute. */
734 attr.origin = origin;
735 attr.flag |= ATTR_FLAG_BIT(BGP_ATTR_ORIGIN);
736
737 /* AS path attribute. */
738 if (aspath)
739 attr.aspath = aspath_intern(aspath);
740 else
741 attr.aspath = aspath_empty();
742 attr.flag |= ATTR_FLAG_BIT(BGP_ATTR_AS_PATH);
743
744 /* Next hop attribute. */
745 attr.flag |= ATTR_FLAG_BIT(BGP_ATTR_NEXT_HOP);
746
747 if (community) {
748 uint32_t gshut = COMMUNITY_GSHUT;
749
750 /* If we are not shutting down ourselves and we are
751 * aggregating a route that contains the GSHUT community we
752 * need to remove that community when creating the aggregate */
753 if (!bgp_flag_check(bgp, BGP_FLAG_GRACEFUL_SHUTDOWN)
754 && community_include(community, gshut)) {
755 community_del_val(community, &gshut);
756 }
757
758 attr.community = community;
759 attr.flag |= ATTR_FLAG_BIT(BGP_ATTR_COMMUNITIES);
760 }
761
762 if (bgp_flag_check(bgp, BGP_FLAG_GRACEFUL_SHUTDOWN)) {
763 bgp_attr_add_gshut_community(&attr);
764 }
765
766 attr.label_index = BGP_INVALID_LABEL_INDEX;
767 attr.label = MPLS_INVALID_LABEL;
768 attr.weight = BGP_ATTR_DEFAULT_WEIGHT;
769 attr.mp_nexthop_len = IPV6_MAX_BYTELEN;
770 if (!as_set || atomic_aggregate)
771 attr.flag |= ATTR_FLAG_BIT(BGP_ATTR_ATOMIC_AGGREGATE);
772 attr.flag |= ATTR_FLAG_BIT(BGP_ATTR_AGGREGATOR);
773 if (CHECK_FLAG(bgp->config, BGP_CONFIG_CONFEDERATION))
774 attr.aggregator_as = bgp->confed_id;
775 else
776 attr.aggregator_as = bgp->as;
777 attr.aggregator_addr = bgp->router_id;
778 attr.label_index = BGP_INVALID_LABEL_INDEX;
779 attr.label = MPLS_INVALID_LABEL;
780
781 new = bgp_attr_intern(&attr);
782
783 aspath_unintern(&new->aspath);
784 return new;
785 }
786
787 /* Unintern just the sub-components of the attr, but not the attr */
788 void bgp_attr_unintern_sub(struct attr *attr)
789 {
790 /* aspath refcount shoud be decrement. */
791 if (attr->aspath)
792 aspath_unintern(&attr->aspath);
793 UNSET_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_AS_PATH));
794
795 if (attr->community)
796 community_unintern(&attr->community);
797 UNSET_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_COMMUNITIES));
798
799 if (attr->ecommunity)
800 ecommunity_unintern(&attr->ecommunity);
801 UNSET_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_EXT_COMMUNITIES));
802
803 if (attr->lcommunity)
804 lcommunity_unintern(&attr->lcommunity);
805 UNSET_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_LARGE_COMMUNITIES));
806
807 if (attr->cluster)
808 cluster_unintern(attr->cluster);
809 UNSET_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_CLUSTER_LIST));
810
811 if (attr->transit)
812 transit_unintern(attr->transit);
813
814 if (attr->encap_subtlvs)
815 encap_unintern(&attr->encap_subtlvs, ENCAP_SUBTLV_TYPE);
816
817 #if ENABLE_BGP_VNC
818 if (attr->vnc_subtlvs)
819 encap_unintern(&attr->vnc_subtlvs, VNC_SUBTLV_TYPE);
820 #endif
821 }
822
823 /*
824 * We have some show commands that let you experimentally
825 * apply a route-map. When we apply the route-map
826 * we are reseting values but not saving them for
827 * posterity via intern'ing( because route-maps don't
828 * do that) but at this point in time we need
829 * to compare the new attr to the old and if the
830 * routemap has changed it we need to, as Snoop Dog says,
831 * Drop it like it's hot
832 */
833 void bgp_attr_undup(struct attr *new, struct attr *old)
834 {
835 if (new->aspath != old->aspath)
836 aspath_free(new->aspath);
837
838 if (new->community != old->community)
839 community_free(new->community);
840
841 if (new->ecommunity != old->ecommunity)
842 ecommunity_free(&new->ecommunity);
843
844 if (new->lcommunity != old->lcommunity)
845 lcommunity_free(&new->lcommunity);
846 }
847
848 /* Free bgp attribute and aspath. */
849 void bgp_attr_unintern(struct attr **pattr)
850 {
851 struct attr *attr = *pattr;
852 struct attr *ret;
853 struct attr tmp;
854
855 /* Decrement attribute reference. */
856 attr->refcnt--;
857
858 tmp = *attr;
859
860 /* If reference becomes zero then free attribute object. */
861 if (attr->refcnt == 0) {
862 ret = hash_release(attrhash, attr);
863 assert(ret != NULL);
864 XFREE(MTYPE_ATTR, attr);
865 *pattr = NULL;
866 }
867
868 bgp_attr_unintern_sub(&tmp);
869 }
870
871 void bgp_attr_flush(struct attr *attr)
872 {
873 if (attr->aspath && !attr->aspath->refcnt) {
874 aspath_free(attr->aspath);
875 attr->aspath = NULL;
876 }
877 if (attr->community && !attr->community->refcnt) {
878 community_free(attr->community);
879 attr->community = NULL;
880 }
881
882 if (attr->ecommunity && !attr->ecommunity->refcnt)
883 ecommunity_free(&attr->ecommunity);
884 if (attr->lcommunity && !attr->lcommunity->refcnt)
885 lcommunity_free(&attr->lcommunity);
886 if (attr->cluster && !attr->cluster->refcnt) {
887 cluster_free(attr->cluster);
888 attr->cluster = NULL;
889 }
890 if (attr->transit && !attr->transit->refcnt) {
891 transit_free(attr->transit);
892 attr->transit = NULL;
893 }
894 if (attr->encap_subtlvs && !attr->encap_subtlvs->refcnt) {
895 encap_free(attr->encap_subtlvs);
896 attr->encap_subtlvs = NULL;
897 }
898 #if ENABLE_BGP_VNC
899 if (attr->vnc_subtlvs && !attr->vnc_subtlvs->refcnt) {
900 encap_free(attr->vnc_subtlvs);
901 attr->vnc_subtlvs = NULL;
902 }
903 #endif
904 }
905
906 /* Implement draft-scudder-idr-optional-transitive behaviour and
907 * avoid resetting sessions for malformed attributes which are
908 * are partial/optional and hence where the error likely was not
909 * introduced by the sending neighbour.
910 */
911 static bgp_attr_parse_ret_t
912 bgp_attr_malformed(struct bgp_attr_parser_args *args, uint8_t subcode,
913 bgp_size_t length)
914 {
915 struct peer *const peer = args->peer;
916 const uint8_t flags = args->flags;
917 /* startp and length must be special-cased, as whether or not to
918 * send the attribute data with the NOTIFY depends on the error,
919 * the caller therefore signals this with the seperate length argument
920 */
921 uint8_t *notify_datap = (length > 0 ? args->startp : NULL);
922
923 /* Only relax error handling for eBGP peers */
924 if (peer->sort != BGP_PEER_EBGP) {
925 bgp_notify_send_with_data(peer, BGP_NOTIFY_UPDATE_ERR, subcode,
926 notify_datap, length);
927 return BGP_ATTR_PARSE_ERROR;
928 }
929
930 /* Adjust the stream getp to the end of the attribute, in case we can
931 * still proceed but the caller hasn't read all the attribute.
932 */
933 stream_set_getp(BGP_INPUT(peer),
934 (args->startp - STREAM_DATA(BGP_INPUT(peer)))
935 + args->total);
936
937 switch (args->type) {
938 /* where an attribute is relatively inconsequential, e.g. it does not
939 * affect route selection, and can be safely ignored, then any such
940 * attributes which are malformed should just be ignored and the route
941 * processed as normal.
942 */
943 case BGP_ATTR_AS4_AGGREGATOR:
944 case BGP_ATTR_AGGREGATOR:
945 case BGP_ATTR_ATOMIC_AGGREGATE:
946 return BGP_ATTR_PARSE_PROCEED;
947
948 /* Core attributes, particularly ones which may influence route
949 * selection, should always cause session resets
950 */
951 case BGP_ATTR_ORIGIN:
952 case BGP_ATTR_AS_PATH:
953 case BGP_ATTR_NEXT_HOP:
954 case BGP_ATTR_MULTI_EXIT_DISC:
955 case BGP_ATTR_LOCAL_PREF:
956 case BGP_ATTR_COMMUNITIES:
957 case BGP_ATTR_ORIGINATOR_ID:
958 case BGP_ATTR_CLUSTER_LIST:
959 case BGP_ATTR_MP_REACH_NLRI:
960 case BGP_ATTR_MP_UNREACH_NLRI:
961 case BGP_ATTR_EXT_COMMUNITIES:
962 bgp_notify_send_with_data(peer, BGP_NOTIFY_UPDATE_ERR, subcode,
963 notify_datap, length);
964 return BGP_ATTR_PARSE_ERROR;
965 }
966
967 /* Partial optional attributes that are malformed should not cause
968 * the whole session to be reset. Instead treat it as a withdrawal
969 * of the routes, if possible.
970 */
971 if (CHECK_FLAG(flags, BGP_ATTR_FLAG_TRANS)
972 && CHECK_FLAG(flags, BGP_ATTR_FLAG_OPTIONAL)
973 && CHECK_FLAG(flags, BGP_ATTR_FLAG_PARTIAL))
974 return BGP_ATTR_PARSE_WITHDRAW;
975
976 /* default to reset */
977 return BGP_ATTR_PARSE_ERROR_NOTIFYPLS;
978 }
979
980 /* Find out what is wrong with the path attribute flag bits and log the error.
981 "Flag bits" here stand for Optional, Transitive and Partial, but not for
982 Extended Length. Checking O/T/P bits at once implies, that the attribute
983 being diagnosed is defined by RFC as either a "well-known" or an "optional,
984 non-transitive" attribute. */
985 static void
986 bgp_attr_flags_diagnose(struct bgp_attr_parser_args *args,
987 uint8_t desired_flags /* how RFC says it must be */
988 )
989 {
990 uint8_t seen = 0, i;
991 uint8_t real_flags = args->flags;
992 const uint8_t attr_code = args->type;
993
994 desired_flags &= ~BGP_ATTR_FLAG_EXTLEN;
995 real_flags &= ~BGP_ATTR_FLAG_EXTLEN;
996 for (i = 0; i <= 2; i++) /* O,T,P, but not E */
997 if (CHECK_FLAG(desired_flags, attr_flag_str[i].key)
998 != CHECK_FLAG(real_flags, attr_flag_str[i].key)) {
999 zlog_err("%s attribute must%s be flagged as \"%s\"",
1000 lookup_msg(attr_str, attr_code, NULL),
1001 CHECK_FLAG(desired_flags, attr_flag_str[i].key)
1002 ? ""
1003 : " not",
1004 attr_flag_str[i].str);
1005 seen = 1;
1006 }
1007 if (!seen) {
1008 zlog_debug(
1009 "Strange, %s called for attr %s, but no problem found with flags"
1010 " (real flags 0x%x, desired 0x%x)",
1011 __func__, lookup_msg(attr_str, attr_code, NULL),
1012 real_flags, desired_flags);
1013 }
1014 }
1015
1016 /* Required flags for attributes. EXTLEN will be masked off when testing,
1017 * as will PARTIAL for optional+transitive attributes.
1018 */
1019 const uint8_t attr_flags_values[] = {
1020 [BGP_ATTR_ORIGIN] = BGP_ATTR_FLAG_TRANS,
1021 [BGP_ATTR_AS_PATH] = BGP_ATTR_FLAG_TRANS,
1022 [BGP_ATTR_NEXT_HOP] = BGP_ATTR_FLAG_TRANS,
1023 [BGP_ATTR_MULTI_EXIT_DISC] = BGP_ATTR_FLAG_OPTIONAL,
1024 [BGP_ATTR_LOCAL_PREF] = BGP_ATTR_FLAG_TRANS,
1025 [BGP_ATTR_ATOMIC_AGGREGATE] = BGP_ATTR_FLAG_TRANS,
1026 [BGP_ATTR_AGGREGATOR] = BGP_ATTR_FLAG_TRANS | BGP_ATTR_FLAG_OPTIONAL,
1027 [BGP_ATTR_COMMUNITIES] = BGP_ATTR_FLAG_TRANS | BGP_ATTR_FLAG_OPTIONAL,
1028 [BGP_ATTR_ORIGINATOR_ID] = BGP_ATTR_FLAG_OPTIONAL,
1029 [BGP_ATTR_CLUSTER_LIST] = BGP_ATTR_FLAG_OPTIONAL,
1030 [BGP_ATTR_MP_REACH_NLRI] = BGP_ATTR_FLAG_OPTIONAL,
1031 [BGP_ATTR_MP_UNREACH_NLRI] = BGP_ATTR_FLAG_OPTIONAL,
1032 [BGP_ATTR_EXT_COMMUNITIES] =
1033 BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS,
1034 [BGP_ATTR_AS4_PATH] = BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS,
1035 [BGP_ATTR_AS4_AGGREGATOR] =
1036 BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS,
1037 [BGP_ATTR_PMSI_TUNNEL] = BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS,
1038 [BGP_ATTR_LARGE_COMMUNITIES] =
1039 BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS,
1040 [BGP_ATTR_PREFIX_SID] = BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS,
1041 };
1042 static const size_t attr_flags_values_max = array_size(attr_flags_values) - 1;
1043
1044 static int bgp_attr_flag_invalid(struct bgp_attr_parser_args *args)
1045 {
1046 uint8_t mask = BGP_ATTR_FLAG_EXTLEN;
1047 const uint8_t flags = args->flags;
1048 const uint8_t attr_code = args->type;
1049
1050 /* there may be attributes we don't know about */
1051 if (attr_code > attr_flags_values_max)
1052 return 0;
1053 if (attr_flags_values[attr_code] == 0)
1054 return 0;
1055
1056 /* RFC4271, "For well-known attributes, the Transitive bit MUST be set
1057 * to
1058 * 1."
1059 */
1060 if (!CHECK_FLAG(BGP_ATTR_FLAG_OPTIONAL, flags)
1061 && !CHECK_FLAG(BGP_ATTR_FLAG_TRANS, flags)) {
1062 zlog_err(
1063 "%s well-known attributes must have transitive flag set (%x)",
1064 lookup_msg(attr_str, attr_code, NULL), flags);
1065 return 1;
1066 }
1067
1068 /* "For well-known attributes and for optional non-transitive
1069 * attributes,
1070 * the Partial bit MUST be set to 0."
1071 */
1072 if (CHECK_FLAG(flags, BGP_ATTR_FLAG_PARTIAL)) {
1073 if (!CHECK_FLAG(flags, BGP_ATTR_FLAG_OPTIONAL)) {
1074 zlog_err(
1075 "%s well-known attribute "
1076 "must NOT have the partial flag set (%x)",
1077 lookup_msg(attr_str, attr_code, NULL), flags);
1078 return 1;
1079 }
1080 if (CHECK_FLAG(flags, BGP_ATTR_FLAG_OPTIONAL)
1081 && !CHECK_FLAG(flags, BGP_ATTR_FLAG_TRANS)) {
1082 zlog_err(
1083 "%s optional + transitive attribute "
1084 "must NOT have the partial flag set (%x)",
1085 lookup_msg(attr_str, attr_code, NULL), flags);
1086 return 1;
1087 }
1088 }
1089
1090 /* Optional transitive attributes may go through speakers that don't
1091 * reocgnise them and set the Partial bit.
1092 */
1093 if (CHECK_FLAG(flags, BGP_ATTR_FLAG_OPTIONAL)
1094 && CHECK_FLAG(flags, BGP_ATTR_FLAG_TRANS))
1095 SET_FLAG(mask, BGP_ATTR_FLAG_PARTIAL);
1096
1097 if ((flags & ~mask) == attr_flags_values[attr_code])
1098 return 0;
1099
1100 bgp_attr_flags_diagnose(args, attr_flags_values[attr_code]);
1101 return 1;
1102 }
1103
1104 /* Get origin attribute of the update message. */
1105 static bgp_attr_parse_ret_t bgp_attr_origin(struct bgp_attr_parser_args *args)
1106 {
1107 struct peer *const peer = args->peer;
1108 struct attr *const attr = args->attr;
1109 const bgp_size_t length = args->length;
1110
1111 /* If any recognized attribute has Attribute Length that conflicts
1112 with the expected length (based on the attribute type code), then
1113 the Error Subcode is set to Attribute Length Error. The Data
1114 field contains the erroneous attribute (type, length and
1115 value). */
1116 if (length != 1) {
1117 zlog_err("Origin attribute length is not one %d", length);
1118 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1119 args->total);
1120 }
1121
1122 /* Fetch origin attribute. */
1123 attr->origin = stream_getc(BGP_INPUT(peer));
1124
1125 /* If the ORIGIN attribute has an undefined value, then the Error
1126 Subcode is set to Invalid Origin Attribute. The Data field
1127 contains the unrecognized attribute (type, length and value). */
1128 if ((attr->origin != BGP_ORIGIN_IGP) && (attr->origin != BGP_ORIGIN_EGP)
1129 && (attr->origin != BGP_ORIGIN_INCOMPLETE)) {
1130 zlog_err("Origin attribute value is invalid %d", attr->origin);
1131 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_INVAL_ORIGIN,
1132 args->total);
1133 }
1134
1135 /* Set oring attribute flag. */
1136 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_ORIGIN);
1137
1138 return 0;
1139 }
1140
1141 /* Parse AS path information. This function is wrapper of
1142 aspath_parse. */
1143 static int bgp_attr_aspath(struct bgp_attr_parser_args *args)
1144 {
1145 struct attr *const attr = args->attr;
1146 struct peer *const peer = args->peer;
1147 const bgp_size_t length = args->length;
1148
1149 /*
1150 * peer with AS4 => will get 4Byte ASnums
1151 * otherwise, will get 16 Bit
1152 */
1153 attr->aspath = aspath_parse(peer->curr, length,
1154 CHECK_FLAG(peer->cap, PEER_CAP_AS4_RCV));
1155
1156 /* In case of IBGP, length will be zero. */
1157 if (!attr->aspath) {
1158 zlog_err("Malformed AS path from %s, length is %d", peer->host,
1159 length);
1160 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_MAL_AS_PATH,
1161 0);
1162 }
1163
1164 /* Set aspath attribute flag. */
1165 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_AS_PATH);
1166
1167 return BGP_ATTR_PARSE_PROCEED;
1168 }
1169
1170 static bgp_attr_parse_ret_t bgp_attr_aspath_check(struct peer *const peer,
1171 struct attr *const attr)
1172 {
1173 /* These checks were part of bgp_attr_aspath, but with
1174 * as4 we should to check aspath things when
1175 * aspath synthesizing with as4_path has already taken place.
1176 * Otherwise we check ASPATH and use the synthesized thing, and that is
1177 * not right.
1178 * So do the checks later, i.e. here
1179 */
1180 struct aspath *aspath;
1181
1182 /* Confederation sanity check. */
1183 if ((peer->sort == BGP_PEER_CONFED
1184 && !aspath_left_confed_check(attr->aspath))
1185 || (peer->sort == BGP_PEER_EBGP
1186 && aspath_confed_check(attr->aspath))) {
1187 zlog_err("Malformed AS path from %s", peer->host);
1188 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
1189 BGP_NOTIFY_UPDATE_MAL_AS_PATH);
1190 return BGP_ATTR_PARSE_ERROR;
1191 }
1192
1193 /* First AS check for EBGP. */
1194 if (CHECK_FLAG(peer->flags, PEER_FLAG_ENFORCE_FIRST_AS)) {
1195 if (peer->sort == BGP_PEER_EBGP
1196 && !aspath_firstas_check(attr->aspath, peer->as)) {
1197 zlog_err("%s incorrect first AS (must be %u)",
1198 peer->host, peer->as);
1199 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
1200 BGP_NOTIFY_UPDATE_MAL_AS_PATH);
1201 return BGP_ATTR_PARSE_ERROR;
1202 }
1203 }
1204
1205 /* local-as prepend */
1206 if (peer->change_local_as
1207 && !CHECK_FLAG(peer->flags, PEER_FLAG_LOCAL_AS_NO_PREPEND)) {
1208 aspath = aspath_dup(attr->aspath);
1209 aspath = aspath_add_seq(aspath, peer->change_local_as);
1210 aspath_unintern(&attr->aspath);
1211 attr->aspath = aspath_intern(aspath);
1212 }
1213
1214 return BGP_ATTR_PARSE_PROCEED;
1215 }
1216
1217 /* Parse AS4 path information. This function is another wrapper of
1218 aspath_parse. */
1219 static int bgp_attr_as4_path(struct bgp_attr_parser_args *args,
1220 struct aspath **as4_path)
1221 {
1222 struct peer *const peer = args->peer;
1223 struct attr *const attr = args->attr;
1224 const bgp_size_t length = args->length;
1225
1226 *as4_path = aspath_parse(peer->curr, length, 1);
1227
1228 /* In case of IBGP, length will be zero. */
1229 if (!*as4_path) {
1230 zlog_err("Malformed AS4 path from %s, length is %d", peer->host,
1231 length);
1232 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_MAL_AS_PATH,
1233 0);
1234 }
1235
1236 /* Set aspath attribute flag. */
1237 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_AS4_PATH);
1238
1239 return BGP_ATTR_PARSE_PROCEED;
1240 }
1241
1242 /* Nexthop attribute. */
1243 static bgp_attr_parse_ret_t bgp_attr_nexthop(struct bgp_attr_parser_args *args)
1244 {
1245 struct peer *const peer = args->peer;
1246 struct attr *const attr = args->attr;
1247 const bgp_size_t length = args->length;
1248
1249 in_addr_t nexthop_h, nexthop_n;
1250
1251 /* Check nexthop attribute length. */
1252 if (length != 4) {
1253 zlog_err("Nexthop attribute length isn't four [%d]", length);
1254
1255 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1256 args->total);
1257 }
1258
1259 /* According to section 6.3 of RFC4271, syntactically incorrect NEXT_HOP
1260 attribute must result in a NOTIFICATION message (this is implemented
1261 below).
1262 At the same time, semantically incorrect NEXT_HOP is more likely to
1263 be just
1264 logged locally (this is implemented somewhere else). The UPDATE
1265 message
1266 gets ignored in any of these cases. */
1267 nexthop_n = stream_get_ipv4(peer->curr);
1268 nexthop_h = ntohl(nexthop_n);
1269 if ((IPV4_NET0(nexthop_h) || IPV4_NET127(nexthop_h)
1270 || IPV4_CLASS_DE(nexthop_h))
1271 && !BGP_DEBUG(
1272 allow_martians,
1273 ALLOW_MARTIANS)) /* loopbacks may be used in testing */
1274 {
1275 char buf[INET_ADDRSTRLEN];
1276 inet_ntop(AF_INET, &nexthop_n, buf, INET_ADDRSTRLEN);
1277 zlog_err("Martian nexthop %s", buf);
1278 return bgp_attr_malformed(
1279 args, BGP_NOTIFY_UPDATE_INVAL_NEXT_HOP, args->total);
1280 }
1281
1282 attr->nexthop.s_addr = nexthop_n;
1283 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_NEXT_HOP);
1284
1285 return BGP_ATTR_PARSE_PROCEED;
1286 }
1287
1288 /* MED atrribute. */
1289 static bgp_attr_parse_ret_t bgp_attr_med(struct bgp_attr_parser_args *args)
1290 {
1291 struct peer *const peer = args->peer;
1292 struct attr *const attr = args->attr;
1293 const bgp_size_t length = args->length;
1294
1295 /* Length check. */
1296 if (length != 4) {
1297 zlog_err("MED attribute length isn't four [%d]", length);
1298
1299 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1300 args->total);
1301 }
1302
1303 attr->med = stream_getl(peer->curr);
1304
1305 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_MULTI_EXIT_DISC);
1306
1307 return BGP_ATTR_PARSE_PROCEED;
1308 }
1309
1310 /* Local preference attribute. */
1311 static bgp_attr_parse_ret_t
1312 bgp_attr_local_pref(struct bgp_attr_parser_args *args)
1313 {
1314 struct peer *const peer = args->peer;
1315 struct attr *const attr = args->attr;
1316 const bgp_size_t length = args->length;
1317
1318 /* Length check. */
1319 if (length != 4) {
1320 zlog_err("LOCAL_PREF attribute length isn't 4 [%u]", length);
1321 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1322 args->total);
1323 }
1324
1325 /* If it is contained in an UPDATE message that is received from an
1326 external peer, then this attribute MUST be ignored by the
1327 receiving speaker. */
1328 if (peer->sort == BGP_PEER_EBGP) {
1329 stream_forward_getp(peer->curr, length);
1330 return BGP_ATTR_PARSE_PROCEED;
1331 }
1332
1333 attr->local_pref = stream_getl(peer->curr);
1334
1335 /* Set the local-pref flag. */
1336 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_LOCAL_PREF);
1337
1338 return BGP_ATTR_PARSE_PROCEED;
1339 }
1340
1341 /* Atomic aggregate. */
1342 static int bgp_attr_atomic(struct bgp_attr_parser_args *args)
1343 {
1344 struct attr *const attr = args->attr;
1345 const bgp_size_t length = args->length;
1346
1347 /* Length check. */
1348 if (length != 0) {
1349 zlog_err("ATOMIC_AGGREGATE attribute length isn't 0 [%u]",
1350 length);
1351 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1352 args->total);
1353 }
1354
1355 /* Set atomic aggregate flag. */
1356 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_ATOMIC_AGGREGATE);
1357
1358 return BGP_ATTR_PARSE_PROCEED;
1359 }
1360
1361 /* Aggregator attribute */
1362 static int bgp_attr_aggregator(struct bgp_attr_parser_args *args)
1363 {
1364 struct peer *const peer = args->peer;
1365 struct attr *const attr = args->attr;
1366 const bgp_size_t length = args->length;
1367
1368 int wantedlen = 6;
1369
1370 /* peer with AS4 will send 4 Byte AS, peer without will send 2 Byte */
1371 if (CHECK_FLAG(peer->cap, PEER_CAP_AS4_RCV))
1372 wantedlen = 8;
1373
1374 if (length != wantedlen) {
1375 zlog_err("AGGREGATOR attribute length isn't %u [%u]", wantedlen,
1376 length);
1377 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1378 args->total);
1379 }
1380
1381 if (CHECK_FLAG(peer->cap, PEER_CAP_AS4_RCV))
1382 attr->aggregator_as = stream_getl(peer->curr);
1383 else
1384 attr->aggregator_as = stream_getw(peer->curr);
1385 attr->aggregator_addr.s_addr = stream_get_ipv4(peer->curr);
1386
1387 /* Set atomic aggregate flag. */
1388 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_AGGREGATOR);
1389
1390 return BGP_ATTR_PARSE_PROCEED;
1391 }
1392
1393 /* New Aggregator attribute */
1394 static bgp_attr_parse_ret_t
1395 bgp_attr_as4_aggregator(struct bgp_attr_parser_args *args,
1396 as_t *as4_aggregator_as,
1397 struct in_addr *as4_aggregator_addr)
1398 {
1399 struct peer *const peer = args->peer;
1400 struct attr *const attr = args->attr;
1401 const bgp_size_t length = args->length;
1402
1403 if (length != 8) {
1404 zlog_err("New Aggregator length is not 8 [%d]", length);
1405 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1406 0);
1407 }
1408
1409 *as4_aggregator_as = stream_getl(peer->curr);
1410 as4_aggregator_addr->s_addr = stream_get_ipv4(peer->curr);
1411
1412 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_AS4_AGGREGATOR);
1413
1414 return BGP_ATTR_PARSE_PROCEED;
1415 }
1416
1417 /* Munge Aggregator and New-Aggregator, AS_PATH and NEW_AS_PATH.
1418 */
1419 static bgp_attr_parse_ret_t
1420 bgp_attr_munge_as4_attrs(struct peer *const peer, struct attr *const attr,
1421 struct aspath *as4_path, as_t as4_aggregator,
1422 struct in_addr *as4_aggregator_addr)
1423 {
1424 int ignore_as4_path = 0;
1425 struct aspath *newpath;
1426
1427 if (!attr->aspath) {
1428 /* NULL aspath shouldn't be possible as bgp_attr_parse should
1429 * have
1430 * checked that all well-known, mandatory attributes were
1431 * present.
1432 *
1433 * Can only be a problem with peer itself - hard error
1434 */
1435 return BGP_ATTR_PARSE_ERROR;
1436 }
1437
1438 if (CHECK_FLAG(peer->cap, PEER_CAP_AS4_RCV)) {
1439 /* peer can do AS4, so we ignore AS4_PATH and AS4_AGGREGATOR
1440 * if given.
1441 * It is worth a warning though, because the peer really
1442 * should not send them
1443 */
1444 if (BGP_DEBUG(as4, AS4)) {
1445 if (attr->flag & (ATTR_FLAG_BIT(BGP_ATTR_AS4_PATH)))
1446 zlog_debug("[AS4] %s %s AS4_PATH", peer->host,
1447 "AS4 capable peer, yet it sent");
1448
1449 if (attr->flag
1450 & (ATTR_FLAG_BIT(BGP_ATTR_AS4_AGGREGATOR)))
1451 zlog_debug("[AS4] %s %s AS4_AGGREGATOR",
1452 peer->host,
1453 "AS4 capable peer, yet it sent");
1454 }
1455
1456 return BGP_ATTR_PARSE_PROCEED;
1457 }
1458
1459 /* We have a asn16 peer. First, look for AS4_AGGREGATOR
1460 * because that may override AS4_PATH
1461 */
1462 if (attr->flag & (ATTR_FLAG_BIT(BGP_ATTR_AS4_AGGREGATOR))) {
1463 if (attr->flag & (ATTR_FLAG_BIT(BGP_ATTR_AGGREGATOR))) {
1464 /* received both.
1465 * if the as_number in aggregator is not AS_TRANS,
1466 * then AS4_AGGREGATOR and AS4_PATH shall be ignored
1467 * and the Aggregator shall be taken as
1468 * info on the aggregating node, and the AS_PATH
1469 * shall be taken as the AS_PATH
1470 * otherwise
1471 * the Aggregator shall be ignored and the
1472 * AS4_AGGREGATOR shall be taken as the
1473 * Aggregating node and the AS_PATH is to be
1474 * constructed "as in all other cases"
1475 */
1476 if (attr->aggregator_as != BGP_AS_TRANS) {
1477 /* ignore */
1478 if (BGP_DEBUG(as4, AS4))
1479 zlog_debug(
1480 "[AS4] %s BGP not AS4 capable peer"
1481 " send AGGREGATOR != AS_TRANS and"
1482 " AS4_AGGREGATOR, so ignore"
1483 " AS4_AGGREGATOR and AS4_PATH",
1484 peer->host);
1485 ignore_as4_path = 1;
1486 } else {
1487 /* "New_aggregator shall be taken as aggregator"
1488 */
1489 attr->aggregator_as = as4_aggregator;
1490 attr->aggregator_addr.s_addr =
1491 as4_aggregator_addr->s_addr;
1492 }
1493 } else {
1494 /* We received a AS4_AGGREGATOR but no AGGREGATOR.
1495 * That is bogus - but reading the conditions
1496 * we have to handle AS4_AGGREGATOR as if it were
1497 * AGGREGATOR in that case
1498 */
1499 if (BGP_DEBUG(as4, AS4))
1500 zlog_debug(
1501 "[AS4] %s BGP not AS4 capable peer send"
1502 " AS4_AGGREGATOR but no AGGREGATOR, will take"
1503 " it as if AGGREGATOR with AS_TRANS had been there",
1504 peer->host);
1505 attr->aggregator_as = as4_aggregator;
1506 /* sweep it under the carpet and simulate a "good"
1507 * AGGREGATOR */
1508 attr->flag |= (ATTR_FLAG_BIT(BGP_ATTR_AGGREGATOR));
1509 }
1510 }
1511
1512 /* need to reconcile NEW_AS_PATH and AS_PATH */
1513 if (!ignore_as4_path
1514 && (attr->flag & (ATTR_FLAG_BIT(BGP_ATTR_AS4_PATH)))) {
1515 newpath = aspath_reconcile_as4(attr->aspath, as4_path);
1516 if (!newpath)
1517 return BGP_ATTR_PARSE_ERROR;
1518
1519 aspath_unintern(&attr->aspath);
1520 attr->aspath = aspath_intern(newpath);
1521 }
1522 return BGP_ATTR_PARSE_PROCEED;
1523 }
1524
1525 /* Community attribute. */
1526 static bgp_attr_parse_ret_t
1527 bgp_attr_community(struct bgp_attr_parser_args *args)
1528 {
1529 struct peer *const peer = args->peer;
1530 struct attr *const attr = args->attr;
1531 const bgp_size_t length = args->length;
1532
1533 if (length == 0) {
1534 attr->community = NULL;
1535 return BGP_ATTR_PARSE_PROCEED;
1536 }
1537
1538 attr->community =
1539 community_parse((uint32_t *)stream_pnt(peer->curr), length);
1540
1541 /* XXX: fix community_parse to use stream API and remove this */
1542 stream_forward_getp(peer->curr, length);
1543
1544 if (!attr->community)
1545 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
1546 args->total);
1547
1548 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_COMMUNITIES);
1549
1550 return BGP_ATTR_PARSE_PROCEED;
1551 }
1552
1553 /* Originator ID attribute. */
1554 static bgp_attr_parse_ret_t
1555 bgp_attr_originator_id(struct bgp_attr_parser_args *args)
1556 {
1557 struct peer *const peer = args->peer;
1558 struct attr *const attr = args->attr;
1559 const bgp_size_t length = args->length;
1560
1561 /* Length check. */
1562 if (length != 4) {
1563 zlog_err("Bad originator ID length %d", length);
1564
1565 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1566 args->total);
1567 }
1568
1569 attr->originator_id.s_addr = stream_get_ipv4(peer->curr);
1570
1571 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_ORIGINATOR_ID);
1572
1573 return BGP_ATTR_PARSE_PROCEED;
1574 }
1575
1576 /* Cluster list attribute. */
1577 static bgp_attr_parse_ret_t
1578 bgp_attr_cluster_list(struct bgp_attr_parser_args *args)
1579 {
1580 struct peer *const peer = args->peer;
1581 struct attr *const attr = args->attr;
1582 const bgp_size_t length = args->length;
1583
1584 /* Check length. */
1585 if (length % 4) {
1586 zlog_err("Bad cluster list length %d", length);
1587
1588 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
1589 args->total);
1590 }
1591
1592 attr->cluster =
1593 cluster_parse((struct in_addr *)stream_pnt(peer->curr), length);
1594
1595 /* XXX: Fix cluster_parse to use stream API and then remove this */
1596 stream_forward_getp(peer->curr, length);
1597
1598 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_CLUSTER_LIST);
1599
1600 return BGP_ATTR_PARSE_PROCEED;
1601 }
1602
1603 /* Multiprotocol reachability information parse. */
1604 int bgp_mp_reach_parse(struct bgp_attr_parser_args *args,
1605 struct bgp_nlri *mp_update)
1606 {
1607 iana_afi_t pkt_afi;
1608 afi_t afi;
1609 iana_safi_t pkt_safi;
1610 safi_t safi;
1611 bgp_size_t nlri_len;
1612 size_t start;
1613 struct stream *s;
1614 struct peer *const peer = args->peer;
1615 struct attr *const attr = args->attr;
1616 const bgp_size_t length = args->length;
1617
1618 /* Set end of packet. */
1619 s = BGP_INPUT(peer);
1620 start = stream_get_getp(s);
1621
1622 /* safe to read statically sized header? */
1623 #define BGP_MP_REACH_MIN_SIZE 5
1624 #define LEN_LEFT (length - (stream_get_getp(s) - start))
1625 if ((length > STREAM_READABLE(s)) || (length < BGP_MP_REACH_MIN_SIZE)) {
1626 zlog_info("%s: %s sent invalid length, %lu", __func__,
1627 peer->host, (unsigned long)length);
1628 return BGP_ATTR_PARSE_ERROR_NOTIFYPLS;
1629 }
1630
1631 /* Load AFI, SAFI. */
1632 pkt_afi = stream_getw(s);
1633 pkt_safi = stream_getc(s);
1634
1635 /* Convert AFI, SAFI to internal values, check. */
1636 if (bgp_map_afi_safi_iana2int(pkt_afi, pkt_safi, &afi, &safi)) {
1637 /* Log if AFI or SAFI is unrecognized. This is not an error
1638 * unless
1639 * the attribute is otherwise malformed.
1640 */
1641 if (bgp_debug_update(peer, NULL, NULL, 0))
1642 zlog_debug(
1643 "%s: MP_REACH received AFI %u or SAFI %u is unrecognized",
1644 peer->host, pkt_afi, pkt_safi);
1645 return BGP_ATTR_PARSE_ERROR;
1646 }
1647
1648 /* Get nexthop length. */
1649 attr->mp_nexthop_len = stream_getc(s);
1650
1651 if (LEN_LEFT < attr->mp_nexthop_len) {
1652 zlog_info(
1653 "%s: %s, MP nexthop length, %u, goes past end of attribute",
1654 __func__, peer->host, attr->mp_nexthop_len);
1655 return BGP_ATTR_PARSE_ERROR_NOTIFYPLS;
1656 }
1657
1658 /* Nexthop length check. */
1659 switch (attr->mp_nexthop_len) {
1660 case 0:
1661 if (safi != SAFI_FLOWSPEC) {
1662 zlog_info("%s: (%s) Wrong multiprotocol next hop length: %d",
1663 __func__, peer->host, attr->mp_nexthop_len);
1664 return BGP_ATTR_PARSE_ERROR_NOTIFYPLS;
1665 }
1666 break;
1667 case BGP_ATTR_NHLEN_VPNV4:
1668 stream_getl(s); /* RD high */
1669 stream_getl(s); /* RD low */
1670 /*
1671 * NOTE: intentional fall through
1672 * - for consistency in rx processing
1673 *
1674 * The following comment is to signal GCC this intention
1675 * and supress the warning
1676 */
1677 /* FALLTHRU */
1678 case BGP_ATTR_NHLEN_IPV4:
1679 stream_get(&attr->mp_nexthop_global_in, s, IPV4_MAX_BYTELEN);
1680 /* Probably needed for RFC 2283 */
1681 if (attr->nexthop.s_addr == 0)
1682 memcpy(&attr->nexthop.s_addr,
1683 &attr->mp_nexthop_global_in, IPV4_MAX_BYTELEN);
1684 break;
1685 case BGP_ATTR_NHLEN_IPV6_GLOBAL:
1686 case BGP_ATTR_NHLEN_VPNV6_GLOBAL:
1687 if (attr->mp_nexthop_len == BGP_ATTR_NHLEN_VPNV6_GLOBAL) {
1688 stream_getl(s); /* RD high */
1689 stream_getl(s); /* RD low */
1690 }
1691 stream_get(&attr->mp_nexthop_global, s, IPV6_MAX_BYTELEN);
1692 if (IN6_IS_ADDR_LINKLOCAL(&attr->mp_nexthop_global))
1693 attr->nh_ifindex = peer->nexthop.ifp->ifindex;
1694 break;
1695 case BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL:
1696 case BGP_ATTR_NHLEN_VPNV6_GLOBAL_AND_LL:
1697 if (attr->mp_nexthop_len
1698 == BGP_ATTR_NHLEN_VPNV6_GLOBAL_AND_LL) {
1699 stream_getl(s); /* RD high */
1700 stream_getl(s); /* RD low */
1701 }
1702 stream_get(&attr->mp_nexthop_global, s, IPV6_MAX_BYTELEN);
1703 if (IN6_IS_ADDR_LINKLOCAL(&attr->mp_nexthop_global))
1704 attr->nh_ifindex = peer->nexthop.ifp->ifindex;
1705 if (attr->mp_nexthop_len
1706 == BGP_ATTR_NHLEN_VPNV6_GLOBAL_AND_LL) {
1707 stream_getl(s); /* RD high */
1708 stream_getl(s); /* RD low */
1709 }
1710 stream_get(&attr->mp_nexthop_local, s, IPV6_MAX_BYTELEN);
1711 if (!IN6_IS_ADDR_LINKLOCAL(&attr->mp_nexthop_local)) {
1712 char buf1[INET6_ADDRSTRLEN];
1713 char buf2[INET6_ADDRSTRLEN];
1714
1715 if (bgp_debug_update(peer, NULL, NULL, 1))
1716 zlog_debug(
1717 "%s rcvd nexthops %s, %s -- ignoring non-LL value",
1718 peer->host,
1719 inet_ntop(AF_INET6,
1720 &attr->mp_nexthop_global,
1721 buf1, INET6_ADDRSTRLEN),
1722 inet_ntop(AF_INET6,
1723 &attr->mp_nexthop_local, buf2,
1724 INET6_ADDRSTRLEN));
1725
1726 attr->mp_nexthop_len = IPV6_MAX_BYTELEN;
1727 }
1728 attr->nh_lla_ifindex = peer->nexthop.ifp->ifindex;
1729 break;
1730 default:
1731 zlog_info("%s: (%s) Wrong multiprotocol next hop length: %d",
1732 __func__, peer->host, attr->mp_nexthop_len);
1733 return BGP_ATTR_PARSE_ERROR_NOTIFYPLS;
1734 }
1735
1736 if (!LEN_LEFT) {
1737 zlog_info("%s: (%s) Failed to read SNPA and NLRI(s)", __func__,
1738 peer->host);
1739 return BGP_ATTR_PARSE_ERROR_NOTIFYPLS;
1740 }
1741
1742 {
1743 uint8_t val;
1744 if ((val = stream_getc(s)))
1745 zlog_warn(
1746 "%s sent non-zero value, %u, for defunct SNPA-length field",
1747 peer->host, val);
1748 }
1749
1750 /* must have nrli_len, what is left of the attribute */
1751 nlri_len = LEN_LEFT;
1752 if (nlri_len > STREAM_READABLE(s)) {
1753 zlog_info("%s: (%s) Failed to read NLRI", __func__, peer->host);
1754 return BGP_ATTR_PARSE_ERROR_NOTIFYPLS;
1755 }
1756
1757 if (!nlri_len) {
1758 zlog_info("%s: (%s) No Reachability, Treating as a EOR marker",
1759 __func__, peer->host);
1760
1761 mp_update->afi = afi;
1762 mp_update->safi = safi;
1763 return BGP_ATTR_PARSE_EOR;
1764 }
1765
1766 mp_update->afi = afi;
1767 mp_update->safi = safi;
1768 mp_update->nlri = stream_pnt(s);
1769 mp_update->length = nlri_len;
1770
1771 stream_forward_getp(s, nlri_len);
1772
1773 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_MP_REACH_NLRI);
1774
1775 return BGP_ATTR_PARSE_PROCEED;
1776 #undef LEN_LEFT
1777 }
1778
1779 /* Multiprotocol unreachable parse */
1780 int bgp_mp_unreach_parse(struct bgp_attr_parser_args *args,
1781 struct bgp_nlri *mp_withdraw)
1782 {
1783 struct stream *s;
1784 iana_afi_t pkt_afi;
1785 afi_t afi;
1786 iana_safi_t pkt_safi;
1787 safi_t safi;
1788 uint16_t withdraw_len;
1789 struct peer *const peer = args->peer;
1790 struct attr *const attr = args->attr;
1791 const bgp_size_t length = args->length;
1792
1793 s = peer->curr;
1794
1795 #define BGP_MP_UNREACH_MIN_SIZE 3
1796 if ((length > STREAM_READABLE(s)) || (length < BGP_MP_UNREACH_MIN_SIZE))
1797 return BGP_ATTR_PARSE_ERROR_NOTIFYPLS;
1798
1799 pkt_afi = stream_getw(s);
1800 pkt_safi = stream_getc(s);
1801
1802 /* Convert AFI, SAFI to internal values, check. */
1803 if (bgp_map_afi_safi_iana2int(pkt_afi, pkt_safi, &afi, &safi)) {
1804 /* Log if AFI or SAFI is unrecognized. This is not an error
1805 * unless
1806 * the attribute is otherwise malformed.
1807 */
1808 if (bgp_debug_update(peer, NULL, NULL, 0))
1809 zlog_debug(
1810 "%s: MP_UNREACH received AFI %u or SAFI %u is unrecognized",
1811 peer->host, pkt_afi, pkt_safi);
1812 return BGP_ATTR_PARSE_ERROR;
1813 }
1814
1815 withdraw_len = length - BGP_MP_UNREACH_MIN_SIZE;
1816
1817 mp_withdraw->afi = afi;
1818 mp_withdraw->safi = safi;
1819 mp_withdraw->nlri = stream_pnt(s);
1820 mp_withdraw->length = withdraw_len;
1821
1822 stream_forward_getp(s, withdraw_len);
1823
1824 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_MP_UNREACH_NLRI);
1825
1826 return BGP_ATTR_PARSE_PROCEED;
1827 }
1828
1829 /* Large Community attribute. */
1830 static bgp_attr_parse_ret_t
1831 bgp_attr_large_community(struct bgp_attr_parser_args *args)
1832 {
1833 struct peer *const peer = args->peer;
1834 struct attr *const attr = args->attr;
1835 const bgp_size_t length = args->length;
1836
1837 /*
1838 * Large community follows new attribute format.
1839 */
1840 if (length == 0) {
1841 attr->lcommunity = NULL;
1842 /* Empty extcomm doesn't seem to be invalid per se */
1843 return BGP_ATTR_PARSE_PROCEED;
1844 }
1845
1846 attr->lcommunity =
1847 lcommunity_parse((uint8_t *)stream_pnt(peer->curr), length);
1848 /* XXX: fix ecommunity_parse to use stream API */
1849 stream_forward_getp(peer->curr, length);
1850
1851 if (!attr->lcommunity)
1852 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
1853 args->total);
1854
1855 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_LARGE_COMMUNITIES);
1856
1857 return BGP_ATTR_PARSE_PROCEED;
1858 }
1859
1860 /* Extended Community attribute. */
1861 static bgp_attr_parse_ret_t
1862 bgp_attr_ext_communities(struct bgp_attr_parser_args *args)
1863 {
1864 struct peer *const peer = args->peer;
1865 struct attr *const attr = args->attr;
1866 const bgp_size_t length = args->length;
1867 uint8_t sticky = 0;
1868
1869 if (length == 0) {
1870 attr->ecommunity = NULL;
1871 /* Empty extcomm doesn't seem to be invalid per se */
1872 return BGP_ATTR_PARSE_PROCEED;
1873 }
1874
1875 attr->ecommunity =
1876 ecommunity_parse((uint8_t *)stream_pnt(peer->curr), length);
1877 /* XXX: fix ecommunity_parse to use stream API */
1878 stream_forward_getp(peer->curr, length);
1879
1880 if (!attr->ecommunity)
1881 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
1882 args->total);
1883
1884 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_EXT_COMMUNITIES);
1885
1886 /* Extract MAC mobility sequence number, if any. */
1887 attr->mm_seqnum = bgp_attr_mac_mobility_seqnum(attr, &sticky);
1888 attr->sticky = sticky;
1889
1890 /* Check if this is a Gateway MAC-IP advertisement */
1891 attr->default_gw = bgp_attr_default_gw(attr);
1892
1893 /* Extract the Rmac, if any */
1894 bgp_attr_rmac(attr, &attr->rmac);
1895
1896 return BGP_ATTR_PARSE_PROCEED;
1897 }
1898
1899 /* Parse Tunnel Encap attribute in an UPDATE */
1900 static int bgp_attr_encap(uint8_t type, struct peer *peer, /* IN */
1901 bgp_size_t length, /* IN: attr's length field */
1902 struct attr *attr, /* IN: caller already allocated */
1903 uint8_t flag, /* IN: attr's flags field */
1904 uint8_t *startp)
1905 {
1906 bgp_size_t total;
1907 uint16_t tunneltype = 0;
1908
1909 total = length + (CHECK_FLAG(flag, BGP_ATTR_FLAG_EXTLEN) ? 4 : 3);
1910
1911 if (!CHECK_FLAG(flag, BGP_ATTR_FLAG_TRANS)
1912 || !CHECK_FLAG(flag, BGP_ATTR_FLAG_OPTIONAL)) {
1913 zlog_info(
1914 "Tunnel Encap attribute flag isn't optional and transitive %d",
1915 flag);
1916 bgp_notify_send_with_data(peer, BGP_NOTIFY_UPDATE_ERR,
1917 BGP_NOTIFY_UPDATE_ATTR_FLAG_ERR,
1918 startp, total);
1919 return -1;
1920 }
1921
1922 if (BGP_ATTR_ENCAP == type) {
1923 /* read outer TLV type and length */
1924 uint16_t tlv_length;
1925
1926 if (length < 4) {
1927 zlog_info(
1928 "Tunnel Encap attribute not long enough to contain outer T,L");
1929 bgp_notify_send_with_data(
1930 peer, BGP_NOTIFY_UPDATE_ERR,
1931 BGP_NOTIFY_UPDATE_OPT_ATTR_ERR, startp, total);
1932 return -1;
1933 }
1934 tunneltype = stream_getw(BGP_INPUT(peer));
1935 tlv_length = stream_getw(BGP_INPUT(peer));
1936 length -= 4;
1937
1938 if (tlv_length != length) {
1939 zlog_info("%s: tlv_length(%d) != length(%d)", __func__,
1940 tlv_length, length);
1941 }
1942 }
1943
1944 while (length >= 4) {
1945 uint16_t subtype = 0;
1946 uint16_t sublength = 0;
1947 struct bgp_attr_encap_subtlv *tlv;
1948
1949 if (BGP_ATTR_ENCAP == type) {
1950 subtype = stream_getc(BGP_INPUT(peer));
1951 sublength = stream_getc(BGP_INPUT(peer));
1952 length -= 2;
1953 #if ENABLE_BGP_VNC
1954 } else {
1955 subtype = stream_getw(BGP_INPUT(peer));
1956 sublength = stream_getw(BGP_INPUT(peer));
1957 length -= 4;
1958 #endif
1959 }
1960
1961 if (sublength > length) {
1962 zlog_info(
1963 "Tunnel Encap attribute sub-tlv length %d exceeds remaining length %d",
1964 sublength, length);
1965 bgp_notify_send_with_data(
1966 peer, BGP_NOTIFY_UPDATE_ERR,
1967 BGP_NOTIFY_UPDATE_OPT_ATTR_ERR, startp, total);
1968 return -1;
1969 }
1970
1971 /* alloc and copy sub-tlv */
1972 /* TBD make sure these are freed when attributes are released */
1973 tlv = XCALLOC(MTYPE_ENCAP_TLV,
1974 sizeof(struct bgp_attr_encap_subtlv) + sublength);
1975 tlv->type = subtype;
1976 tlv->length = sublength;
1977 stream_get(tlv->value, peer->curr, sublength);
1978 length -= sublength;
1979
1980 /* attach tlv to encap chain */
1981 if (BGP_ATTR_ENCAP == type) {
1982 struct bgp_attr_encap_subtlv *stlv_last;
1983 for (stlv_last = attr->encap_subtlvs;
1984 stlv_last && stlv_last->next;
1985 stlv_last = stlv_last->next)
1986 ;
1987 if (stlv_last) {
1988 stlv_last->next = tlv;
1989 } else {
1990 attr->encap_subtlvs = tlv;
1991 }
1992 #if ENABLE_BGP_VNC
1993 } else {
1994 struct bgp_attr_encap_subtlv *stlv_last;
1995 for (stlv_last = attr->vnc_subtlvs;
1996 stlv_last && stlv_last->next;
1997 stlv_last = stlv_last->next)
1998 ;
1999 if (stlv_last) {
2000 stlv_last->next = tlv;
2001 } else {
2002 attr->vnc_subtlvs = tlv;
2003 }
2004 #endif
2005 }
2006 }
2007
2008 if (BGP_ATTR_ENCAP == type) {
2009 attr->encap_tunneltype = tunneltype;
2010 }
2011
2012 if (length) {
2013 /* spurious leftover data */
2014 zlog_info(
2015 "Tunnel Encap attribute length is bad: %d leftover octets",
2016 length);
2017 bgp_notify_send_with_data(peer, BGP_NOTIFY_UPDATE_ERR,
2018 BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
2019 startp, total);
2020 return -1;
2021 }
2022
2023 return 0;
2024 }
2025
2026 /*
2027 * Read an individual SID value returning how much data we have read
2028 * Returns 0 if there was an error that needs to be passed up the stack
2029 */
2030 static bgp_attr_parse_ret_t bgp_attr_psid_sub(int32_t type,
2031 int32_t length,
2032 struct bgp_attr_parser_args *args,
2033 struct bgp_nlri *mp_update)
2034 {
2035 struct peer *const peer = args->peer;
2036 struct attr *const attr = args->attr;
2037 uint32_t label_index;
2038 struct in6_addr ipv6_sid;
2039 uint32_t srgb_base;
2040 uint32_t srgb_range;
2041 int srgb_count;
2042
2043 if (type == BGP_PREFIX_SID_LABEL_INDEX) {
2044 if (length != BGP_PREFIX_SID_LABEL_INDEX_LENGTH) {
2045 zlog_err(
2046 "Prefix SID label index length is %d instead of %d",
2047 length,
2048 BGP_PREFIX_SID_LABEL_INDEX_LENGTH);
2049 return bgp_attr_malformed(args,
2050 BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
2051 args->total);
2052 }
2053
2054 /* Ignore flags and reserved */
2055 stream_getc(peer->curr);
2056 stream_getw(peer->curr);
2057
2058 /* Fetch the label index and see if it is valid. */
2059 label_index = stream_getl(peer->curr);
2060 if (label_index == BGP_INVALID_LABEL_INDEX)
2061 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
2062 args->total);
2063
2064 /* Store label index; subsequently, we'll check on
2065 * address-family */
2066 attr->label_index = label_index;
2067
2068 /*
2069 * Ignore the Label index attribute unless received for
2070 * labeled-unicast
2071 * SAFI.
2072 */
2073 if (!mp_update->length
2074 || mp_update->safi != SAFI_LABELED_UNICAST)
2075 attr->label_index = BGP_INVALID_LABEL_INDEX;
2076 }
2077
2078 /* Placeholder code for the IPv6 SID type */
2079 else if (type == BGP_PREFIX_SID_IPV6) {
2080 if (length != BGP_PREFIX_SID_IPV6_LENGTH) {
2081 zlog_err("Prefix SID IPv6 length is %d instead of %d",
2082 length, BGP_PREFIX_SID_IPV6_LENGTH);
2083 return bgp_attr_malformed(args,
2084 BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
2085 args->total);
2086 }
2087
2088 /* Ignore reserved */
2089 stream_getc(peer->curr);
2090 stream_getw(peer->curr);
2091
2092 stream_get(&ipv6_sid, peer->curr, 16);
2093 }
2094
2095 /* Placeholder code for the Originator SRGB type */
2096 else if (type == BGP_PREFIX_SID_ORIGINATOR_SRGB) {
2097 /* Ignore flags */
2098 stream_getw(peer->curr);
2099
2100 length -= 2;
2101
2102 if (length % BGP_PREFIX_SID_ORIGINATOR_SRGB_LENGTH) {
2103 zlog_err(
2104 "Prefix SID Originator SRGB length is %d, it must be a multiple of %d ",
2105 length, BGP_PREFIX_SID_ORIGINATOR_SRGB_LENGTH);
2106 return bgp_attr_malformed(
2107 args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
2108 args->total);
2109 }
2110
2111 srgb_count = length / BGP_PREFIX_SID_ORIGINATOR_SRGB_LENGTH;
2112
2113 for (int i = 0; i < srgb_count; i++) {
2114 stream_get(&srgb_base, peer->curr, 3);
2115 stream_get(&srgb_range, peer->curr, 3);
2116 }
2117 }
2118
2119 return BGP_ATTR_PARSE_PROCEED;
2120 }
2121
2122 /* Prefix SID attribute
2123 * draft-ietf-idr-bgp-prefix-sid-05
2124 */
2125 bgp_attr_parse_ret_t
2126 bgp_attr_prefix_sid(int32_t tlength, struct bgp_attr_parser_args *args,
2127 struct bgp_nlri *mp_update)
2128 {
2129 struct peer *const peer = args->peer;
2130 struct attr *const attr = args->attr;
2131 bgp_attr_parse_ret_t ret;
2132
2133 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_PREFIX_SID);
2134
2135 while (tlength) {
2136 int32_t type, length;
2137
2138 type = stream_getc(peer->curr);
2139 length = stream_getw(peer->curr);
2140
2141 ret = bgp_attr_psid_sub(type, length, args, mp_update);
2142
2143 if (ret != BGP_ATTR_PARSE_PROCEED)
2144 return ret;
2145 /*
2146 * Subtract length + the T and the L
2147 * since length is the Vector portion
2148 */
2149 tlength -= length + 3;
2150
2151 if (tlength < 0) {
2152 zlog_err("Prefix SID internal length %d causes us to read beyond the total Prefix SID length",
2153 length);
2154 return bgp_attr_malformed(args,
2155 BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
2156 args->total);
2157 }
2158 }
2159
2160 return BGP_ATTR_PARSE_PROCEED;
2161 }
2162
2163 /* PMSI tunnel attribute (RFC 6514)
2164 * Basic validation checks done here.
2165 */
2166 static bgp_attr_parse_ret_t
2167 bgp_attr_pmsi_tunnel(struct bgp_attr_parser_args *args)
2168 {
2169 struct peer *const peer = args->peer;
2170 struct attr *const attr = args->attr;
2171 const bgp_size_t length = args->length;
2172 uint8_t tnl_type;
2173
2174 /* Verify that the receiver is expecting "ingress replication" as we
2175 * can only support that.
2176 */
2177 if (length < 2) {
2178 zlog_err("Bad PMSI tunnel attribute length %d", length);
2179 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
2180 args->total);
2181 }
2182 stream_getc(peer->curr); /* Flags */
2183 tnl_type = stream_getc(peer->curr);
2184 if (tnl_type > PMSI_TNLTYPE_MAX) {
2185 zlog_err("Invalid PMSI tunnel attribute type %d", tnl_type);
2186 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_OPT_ATTR_ERR,
2187 args->total);
2188 }
2189 if (tnl_type == PMSI_TNLTYPE_INGR_REPL) {
2190 if (length != 9) {
2191 zlog_err("Bad PMSI tunnel attribute length %d for IR",
2192 length);
2193 return bgp_attr_malformed(
2194 args, BGP_NOTIFY_UPDATE_ATTR_LENG_ERR,
2195 args->total);
2196 }
2197 }
2198
2199 attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_PMSI_TUNNEL);
2200 attr->pmsi_tnl_type = tnl_type;
2201
2202 /* Forward read pointer of input stream. */
2203 stream_forward_getp(peer->curr, length - 2);
2204
2205 return BGP_ATTR_PARSE_PROCEED;
2206 }
2207
2208 /* BGP unknown attribute treatment. */
2209 static bgp_attr_parse_ret_t bgp_attr_unknown(struct bgp_attr_parser_args *args)
2210 {
2211 bgp_size_t total = args->total;
2212 struct transit *transit;
2213 struct peer *const peer = args->peer;
2214 struct attr *const attr = args->attr;
2215 uint8_t *const startp = args->startp;
2216 const uint8_t type = args->type;
2217 const uint8_t flag = args->flags;
2218 const bgp_size_t length = args->length;
2219
2220 if (bgp_debug_update(peer, NULL, NULL, 1))
2221 zlog_debug(
2222 "%s Unknown attribute is received (type %d, length %d)",
2223 peer->host, type, length);
2224
2225 /* Forward read pointer of input stream. */
2226 stream_forward_getp(peer->curr, length);
2227
2228 /* If any of the mandatory well-known attributes are not recognized,
2229 then the Error Subcode is set to Unrecognized Well-known
2230 Attribute. The Data field contains the unrecognized attribute
2231 (type, length and value). */
2232 if (!CHECK_FLAG(flag, BGP_ATTR_FLAG_OPTIONAL)) {
2233 return bgp_attr_malformed(args, BGP_NOTIFY_UPDATE_UNREC_ATTR,
2234 args->total);
2235 }
2236
2237 /* Unrecognized non-transitive optional attributes must be quietly
2238 ignored and not passed along to other BGP peers. */
2239 if (!CHECK_FLAG(flag, BGP_ATTR_FLAG_TRANS))
2240 return BGP_ATTR_PARSE_PROCEED;
2241
2242 /* If a path with recognized transitive optional attribute is
2243 accepted and passed along to other BGP peers and the Partial bit
2244 in the Attribute Flags octet is set to 1 by some previous AS, it
2245 is not set back to 0 by the current AS. */
2246 SET_FLAG(*startp, BGP_ATTR_FLAG_PARTIAL);
2247
2248 /* Store transitive attribute to the end of attr->transit. */
2249 if (!attr->transit)
2250 attr->transit = XCALLOC(MTYPE_TRANSIT, sizeof(struct transit));
2251
2252 transit = attr->transit;
2253
2254 if (transit->val)
2255 transit->val = XREALLOC(MTYPE_TRANSIT_VAL, transit->val,
2256 transit->length + total);
2257 else
2258 transit->val = XMALLOC(MTYPE_TRANSIT_VAL, total);
2259
2260 memcpy(transit->val + transit->length, startp, total);
2261 transit->length += total;
2262
2263 return BGP_ATTR_PARSE_PROCEED;
2264 }
2265
2266 /* Well-known attribute check. */
2267 static int bgp_attr_check(struct peer *peer, struct attr *attr)
2268 {
2269 uint8_t type = 0;
2270
2271 /* BGP Graceful-Restart End-of-RIB for IPv4 unicast is signaled as an
2272 * empty UPDATE. */
2273 if (CHECK_FLAG(peer->cap, PEER_CAP_RESTART_RCV) && !attr->flag)
2274 return BGP_ATTR_PARSE_PROCEED;
2275
2276 /* "An UPDATE message that contains the MP_UNREACH_NLRI is not required
2277 to carry any other path attributes.", though if MP_REACH_NLRI or NLRI
2278 are present, it should. Check for any other attribute being present
2279 instead.
2280 */
2281 if ((!CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_MP_REACH_NLRI)) &&
2282 CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_MP_UNREACH_NLRI))))
2283 return BGP_ATTR_PARSE_PROCEED;
2284
2285 if (!CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_ORIGIN)))
2286 type = BGP_ATTR_ORIGIN;
2287
2288 if (!CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_AS_PATH)))
2289 type = BGP_ATTR_AS_PATH;
2290
2291 /* RFC 2858 makes Next-Hop optional/ignored, if MP_REACH_NLRI is present
2292 * and
2293 * NLRI is empty. We can't easily check NLRI empty here though.
2294 */
2295 if (!CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_NEXT_HOP))
2296 && !CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_MP_REACH_NLRI)))
2297 type = BGP_ATTR_NEXT_HOP;
2298
2299 if (peer->sort == BGP_PEER_IBGP
2300 && !CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_LOCAL_PREF)))
2301 type = BGP_ATTR_LOCAL_PREF;
2302
2303 if (type) {
2304 zlog_warn("%s Missing well-known attribute %s.", peer->host,
2305 lookup_msg(attr_str, type, NULL));
2306 bgp_notify_send_with_data(peer, BGP_NOTIFY_UPDATE_ERR,
2307 BGP_NOTIFY_UPDATE_MISS_ATTR, &type,
2308 1);
2309 return BGP_ATTR_PARSE_ERROR;
2310 }
2311 return BGP_ATTR_PARSE_PROCEED;
2312 }
2313
2314 /* Read attribute of update packet. This function is called from
2315 bgp_update_receive() in bgp_packet.c. */
2316 bgp_attr_parse_ret_t bgp_attr_parse(struct peer *peer, struct attr *attr,
2317 bgp_size_t size, struct bgp_nlri *mp_update,
2318 struct bgp_nlri *mp_withdraw)
2319 {
2320 int ret;
2321 uint8_t flag = 0;
2322 uint8_t type = 0;
2323 bgp_size_t length;
2324 uint8_t *startp, *endp;
2325 uint8_t *attr_endp;
2326 uint8_t seen[BGP_ATTR_BITMAP_SIZE];
2327 /* we need the as4_path only until we have synthesized the as_path with
2328 * it */
2329 /* same goes for as4_aggregator */
2330 struct aspath *as4_path = NULL;
2331 as_t as4_aggregator = 0;
2332 struct in_addr as4_aggregator_addr = {.s_addr = 0};
2333
2334 /* Initialize bitmap. */
2335 memset(seen, 0, BGP_ATTR_BITMAP_SIZE);
2336
2337 /* End pointer of BGP attribute. */
2338 endp = BGP_INPUT_PNT(peer) + size;
2339
2340 /* Get attributes to the end of attribute length. */
2341 while (BGP_INPUT_PNT(peer) < endp) {
2342 /* Check remaining length check.*/
2343 if (endp - BGP_INPUT_PNT(peer) < BGP_ATTR_MIN_LEN) {
2344 /* XXX warning: long int format, int arg (arg 5) */
2345 zlog_warn(
2346 "%s: error BGP attribute length %lu is smaller than min len",
2347 peer->host,
2348 (unsigned long)(endp
2349 - stream_pnt(BGP_INPUT(peer))));
2350
2351 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
2352 BGP_NOTIFY_UPDATE_ATTR_LENG_ERR);
2353 return BGP_ATTR_PARSE_ERROR;
2354 }
2355
2356 /* Fetch attribute flag and type. */
2357 startp = BGP_INPUT_PNT(peer);
2358 /* "The lower-order four bits of the Attribute Flags octet are
2359 unused. They MUST be zero when sent and MUST be ignored when
2360 received." */
2361 flag = 0xF0 & stream_getc(BGP_INPUT(peer));
2362 type = stream_getc(BGP_INPUT(peer));
2363
2364 /* Check whether Extended-Length applies and is in bounds */
2365 if (CHECK_FLAG(flag, BGP_ATTR_FLAG_EXTLEN)
2366 && ((endp - startp) < (BGP_ATTR_MIN_LEN + 1))) {
2367 zlog_warn(
2368 "%s: Extended length set, but just %lu bytes of attr header",
2369 peer->host,
2370 (unsigned long)(endp
2371 - stream_pnt(BGP_INPUT(peer))));
2372
2373 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
2374 BGP_NOTIFY_UPDATE_ATTR_LENG_ERR);
2375 return BGP_ATTR_PARSE_ERROR;
2376 }
2377
2378 /* Check extended attribue length bit. */
2379 if (CHECK_FLAG(flag, BGP_ATTR_FLAG_EXTLEN))
2380 length = stream_getw(BGP_INPUT(peer));
2381 else
2382 length = stream_getc(BGP_INPUT(peer));
2383
2384 /* If any attribute appears more than once in the UPDATE
2385 message, then the Error Subcode is set to Malformed Attribute
2386 List. */
2387
2388 if (CHECK_BITMAP(seen, type)) {
2389 zlog_warn(
2390 "%s: error BGP attribute type %d appears twice in a message",
2391 peer->host, type);
2392
2393 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
2394 BGP_NOTIFY_UPDATE_MAL_ATTR);
2395 return BGP_ATTR_PARSE_ERROR;
2396 }
2397
2398 /* Set type to bitmap to check duplicate attribute. `type' is
2399 unsigned char so it never overflow bitmap range. */
2400
2401 SET_BITMAP(seen, type);
2402
2403 /* Overflow check. */
2404 attr_endp = BGP_INPUT_PNT(peer) + length;
2405
2406 if (attr_endp > endp) {
2407 zlog_warn(
2408 "%s: BGP type %d length %d is too large, attribute total length is %d. attr_endp is %p. endp is %p",
2409 peer->host, type, length, size, attr_endp,
2410 endp);
2411 /*
2412 * RFC 4271 6.3
2413 * If any recognized attribute has an Attribute
2414 * Length that conflicts with the expected length
2415 * (based on the attribute type code), then the
2416 * Error Subcode MUST be set to Attribute Length
2417 * Error. The Data field MUST contain the erroneous
2418 * attribute (type, length, and value).
2419 * ----------
2420 * We do not currently have a good way to determine the
2421 * length of the attribute independent of the length
2422 * received in the message. Instead we send the
2423 * minimum between the amount of data we have and the
2424 * amount specified by the attribute length field.
2425 *
2426 * Instead of directly passing in the packet buffer and
2427 * offset we use the stream_get* functions to read into
2428 * a stack buffer, since they perform bounds checking
2429 * and we are working with untrusted data.
2430 */
2431 unsigned char ndata[BGP_MAX_PACKET_SIZE];
2432 memset(ndata, 0x00, sizeof(ndata));
2433 size_t lfl =
2434 CHECK_FLAG(flag, BGP_ATTR_FLAG_EXTLEN) ? 2 : 1;
2435 /* Rewind to end of flag field */
2436 stream_forward_getp(BGP_INPUT(peer), -(1 + lfl));
2437 /* Type */
2438 stream_get(&ndata[0], BGP_INPUT(peer), 1);
2439 /* Length */
2440 stream_get(&ndata[1], BGP_INPUT(peer), lfl);
2441 /* Value */
2442 size_t atl = attr_endp - startp;
2443 size_t ndl = MIN(atl, STREAM_READABLE(BGP_INPUT(peer)));
2444 stream_get(&ndata[lfl + 1], BGP_INPUT(peer), ndl);
2445
2446 bgp_notify_send_with_data(
2447 peer, BGP_NOTIFY_UPDATE_ERR,
2448 BGP_NOTIFY_UPDATE_ATTR_LENG_ERR, ndata,
2449 ndl + lfl + 1);
2450
2451 return BGP_ATTR_PARSE_ERROR;
2452 }
2453
2454 struct bgp_attr_parser_args attr_args = {
2455 .peer = peer,
2456 .length = length,
2457 .attr = attr,
2458 .type = type,
2459 .flags = flag,
2460 .startp = startp,
2461 .total = attr_endp - startp,
2462 };
2463
2464
2465 /* If any recognized attribute has Attribute Flags that conflict
2466 with the Attribute Type Code, then the Error Subcode is set
2467 to
2468 Attribute Flags Error. The Data field contains the erroneous
2469 attribute (type, length and value). */
2470 if (bgp_attr_flag_invalid(&attr_args)) {
2471 bgp_attr_parse_ret_t ret;
2472 ret = bgp_attr_malformed(
2473 &attr_args, BGP_NOTIFY_UPDATE_ATTR_FLAG_ERR,
2474 attr_args.total);
2475 if (ret == BGP_ATTR_PARSE_PROCEED)
2476 continue;
2477 return ret;
2478 }
2479
2480 /* OK check attribute and store it's value. */
2481 switch (type) {
2482 case BGP_ATTR_ORIGIN:
2483 ret = bgp_attr_origin(&attr_args);
2484 break;
2485 case BGP_ATTR_AS_PATH:
2486 ret = bgp_attr_aspath(&attr_args);
2487 break;
2488 case BGP_ATTR_AS4_PATH:
2489 ret = bgp_attr_as4_path(&attr_args, &as4_path);
2490 break;
2491 case BGP_ATTR_NEXT_HOP:
2492 ret = bgp_attr_nexthop(&attr_args);
2493 break;
2494 case BGP_ATTR_MULTI_EXIT_DISC:
2495 ret = bgp_attr_med(&attr_args);
2496 break;
2497 case BGP_ATTR_LOCAL_PREF:
2498 ret = bgp_attr_local_pref(&attr_args);
2499 break;
2500 case BGP_ATTR_ATOMIC_AGGREGATE:
2501 ret = bgp_attr_atomic(&attr_args);
2502 break;
2503 case BGP_ATTR_AGGREGATOR:
2504 ret = bgp_attr_aggregator(&attr_args);
2505 break;
2506 case BGP_ATTR_AS4_AGGREGATOR:
2507 ret = bgp_attr_as4_aggregator(&attr_args,
2508 &as4_aggregator,
2509 &as4_aggregator_addr);
2510 break;
2511 case BGP_ATTR_COMMUNITIES:
2512 ret = bgp_attr_community(&attr_args);
2513 break;
2514 case BGP_ATTR_LARGE_COMMUNITIES:
2515 ret = bgp_attr_large_community(&attr_args);
2516 break;
2517 case BGP_ATTR_ORIGINATOR_ID:
2518 ret = bgp_attr_originator_id(&attr_args);
2519 break;
2520 case BGP_ATTR_CLUSTER_LIST:
2521 ret = bgp_attr_cluster_list(&attr_args);
2522 break;
2523 case BGP_ATTR_MP_REACH_NLRI:
2524 ret = bgp_mp_reach_parse(&attr_args, mp_update);
2525 break;
2526 case BGP_ATTR_MP_UNREACH_NLRI:
2527 ret = bgp_mp_unreach_parse(&attr_args, mp_withdraw);
2528 break;
2529 case BGP_ATTR_EXT_COMMUNITIES:
2530 ret = bgp_attr_ext_communities(&attr_args);
2531 break;
2532 #if ENABLE_BGP_VNC
2533 case BGP_ATTR_VNC:
2534 #endif
2535 case BGP_ATTR_ENCAP:
2536 ret = bgp_attr_encap(type, peer, length, attr, flag,
2537 startp);
2538 break;
2539 case BGP_ATTR_PREFIX_SID:
2540 ret = bgp_attr_prefix_sid(length,
2541 &attr_args, mp_update);
2542 break;
2543 case BGP_ATTR_PMSI_TUNNEL:
2544 ret = bgp_attr_pmsi_tunnel(&attr_args);
2545 break;
2546 default:
2547 ret = bgp_attr_unknown(&attr_args);
2548 break;
2549 }
2550
2551 if (ret == BGP_ATTR_PARSE_ERROR_NOTIFYPLS) {
2552 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
2553 BGP_NOTIFY_UPDATE_MAL_ATTR);
2554 ret = BGP_ATTR_PARSE_ERROR;
2555 }
2556
2557 if (ret == BGP_ATTR_PARSE_EOR) {
2558 if (as4_path)
2559 aspath_unintern(&as4_path);
2560 return ret;
2561 }
2562
2563 /* If hard error occured immediately return to the caller. */
2564 if (ret == BGP_ATTR_PARSE_ERROR) {
2565 zlog_warn("%s: Attribute %s, parse error", peer->host,
2566 lookup_msg(attr_str, type, NULL));
2567 if (as4_path)
2568 aspath_unintern(&as4_path);
2569 return ret;
2570 }
2571 if (ret == BGP_ATTR_PARSE_WITHDRAW) {
2572
2573 zlog_warn(
2574 "%s: Attribute %s, parse error - treating as withdrawal",
2575 peer->host, lookup_msg(attr_str, type, NULL));
2576 if (as4_path)
2577 aspath_unintern(&as4_path);
2578 return ret;
2579 }
2580
2581 /* Check the fetched length. */
2582 if (BGP_INPUT_PNT(peer) != attr_endp) {
2583 zlog_warn("%s: BGP attribute %s, fetch error",
2584 peer->host, lookup_msg(attr_str, type, NULL));
2585 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
2586 BGP_NOTIFY_UPDATE_ATTR_LENG_ERR);
2587 if (as4_path)
2588 aspath_unintern(&as4_path);
2589 return BGP_ATTR_PARSE_ERROR;
2590 }
2591 }
2592
2593 /* Check final read pointer is same as end pointer. */
2594 if (BGP_INPUT_PNT(peer) != endp) {
2595 zlog_warn("%s: BGP attribute %s, length mismatch", peer->host,
2596 lookup_msg(attr_str, type, NULL));
2597 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
2598 BGP_NOTIFY_UPDATE_ATTR_LENG_ERR);
2599 if (as4_path)
2600 aspath_unintern(&as4_path);
2601 return BGP_ATTR_PARSE_ERROR;
2602 }
2603
2604 /* Check all mandatory well-known attributes are present */
2605 {
2606 bgp_attr_parse_ret_t ret;
2607 if ((ret = bgp_attr_check(peer, attr)) < 0) {
2608 if (as4_path)
2609 aspath_unintern(&as4_path);
2610 return ret;
2611 }
2612 }
2613
2614 /*
2615 * At this place we can see whether we got AS4_PATH and/or
2616 * AS4_AGGREGATOR from a 16Bit peer and act accordingly.
2617 * We can not do this before we've read all attributes because
2618 * the as4 handling does not say whether AS4_PATH has to be sent
2619 * after AS_PATH or not - and when AS4_AGGREGATOR will be send
2620 * in relationship to AGGREGATOR.
2621 * So, to be defensive, we are not relying on any order and read
2622 * all attributes first, including these 32bit ones, and now,
2623 * afterwards, we look what and if something is to be done for as4.
2624 *
2625 * It is possible to not have AS_PATH, e.g. GR EoR and sole
2626 * MP_UNREACH_NLRI.
2627 */
2628 /* actually... this doesn't ever return failure currently, but
2629 * better safe than sorry */
2630 if (CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_AS_PATH))
2631 && bgp_attr_munge_as4_attrs(peer, attr, as4_path, as4_aggregator,
2632 &as4_aggregator_addr)) {
2633 bgp_notify_send(peer, BGP_NOTIFY_UPDATE_ERR,
2634 BGP_NOTIFY_UPDATE_MAL_ATTR);
2635 if (as4_path)
2636 aspath_unintern(&as4_path);
2637 return BGP_ATTR_PARSE_ERROR;
2638 }
2639
2640 /* At this stage, we have done all fiddling with as4, and the
2641 * resulting info is in attr->aggregator resp. attr->aspath
2642 * so we can chuck as4_aggregator and as4_path alltogether in
2643 * order to save memory
2644 */
2645 if (as4_path) {
2646 aspath_unintern(&as4_path); /* unintern - it is in the hash */
2647 /* The flag that we got this is still there, but that does not
2648 * do any trouble
2649 */
2650 }
2651 /*
2652 * The "rest" of the code does nothing with as4_aggregator.
2653 * there is no memory attached specifically which is not part
2654 * of the attr.
2655 * so ignoring just means do nothing.
2656 */
2657 /*
2658 * Finally do the checks on the aspath we did not do yet
2659 * because we waited for a potentially synthesized aspath.
2660 */
2661 if (attr->flag & (ATTR_FLAG_BIT(BGP_ATTR_AS_PATH))) {
2662 ret = bgp_attr_aspath_check(peer, attr);
2663 if (ret != BGP_ATTR_PARSE_PROCEED)
2664 return ret;
2665 }
2666 /* Finally intern unknown attribute. */
2667 if (attr->transit)
2668 attr->transit = transit_intern(attr->transit);
2669 if (attr->encap_subtlvs)
2670 attr->encap_subtlvs =
2671 encap_intern(attr->encap_subtlvs, ENCAP_SUBTLV_TYPE);
2672 #if ENABLE_BGP_VNC
2673 if (attr->vnc_subtlvs)
2674 attr->vnc_subtlvs =
2675 encap_intern(attr->vnc_subtlvs, VNC_SUBTLV_TYPE);
2676 #endif
2677
2678 return BGP_ATTR_PARSE_PROCEED;
2679 }
2680
2681 size_t bgp_packet_mpattr_start(struct stream *s, struct peer *peer, afi_t afi,
2682 safi_t safi, struct bpacket_attr_vec_arr *vecarr,
2683 struct attr *attr)
2684 {
2685 size_t sizep;
2686 iana_afi_t pkt_afi;
2687 iana_safi_t pkt_safi;
2688 afi_t nh_afi;
2689
2690 /* Set extended bit always to encode the attribute length as 2 bytes */
2691 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_EXTLEN);
2692 stream_putc(s, BGP_ATTR_MP_REACH_NLRI);
2693 sizep = stream_get_endp(s);
2694 stream_putw(s, 0); /* Marker: Attribute length. */
2695
2696
2697 /* Convert AFI, SAFI to values for packet. */
2698 bgp_map_afi_safi_int2iana(afi, safi, &pkt_afi, &pkt_safi);
2699
2700 stream_putw(s, pkt_afi); /* AFI */
2701 stream_putc(s, pkt_safi); /* SAFI */
2702
2703 /* Nexthop AFI */
2704 if (afi == AFI_IP
2705 && (safi == SAFI_UNICAST || safi == SAFI_LABELED_UNICAST))
2706 nh_afi = peer_cap_enhe(peer, afi, safi) ? AFI_IP6 : AFI_IP;
2707 else
2708 nh_afi = BGP_NEXTHOP_AFI_FROM_NHLEN(attr->mp_nexthop_len);
2709
2710 /* Nexthop */
2711 bpacket_attr_vec_arr_set_vec(vecarr, BGP_ATTR_VEC_NH, s, attr);
2712 switch (nh_afi) {
2713 case AFI_IP:
2714 switch (safi) {
2715 case SAFI_UNICAST:
2716 case SAFI_MULTICAST:
2717 case SAFI_LABELED_UNICAST:
2718 stream_putc(s, 4);
2719 stream_put_ipv4(s, attr->nexthop.s_addr);
2720 break;
2721 case SAFI_MPLS_VPN:
2722 stream_putc(s, 12);
2723 stream_putl(s, 0); /* RD = 0, per RFC */
2724 stream_putl(s, 0);
2725 stream_put(s, &attr->mp_nexthop_global_in, 4);
2726 break;
2727 case SAFI_ENCAP:
2728 case SAFI_EVPN:
2729 stream_putc(s, 4);
2730 stream_put(s, &attr->mp_nexthop_global_in, 4);
2731 break;
2732 case SAFI_FLOWSPEC:
2733 stream_putc(s, 0); /* no nexthop for flowspec */
2734 default:
2735 break;
2736 }
2737 break;
2738 case AFI_IP6:
2739 switch (safi) {
2740 case SAFI_UNICAST:
2741 case SAFI_MULTICAST:
2742 case SAFI_LABELED_UNICAST:
2743 case SAFI_EVPN: {
2744 if (attr->mp_nexthop_len
2745 == BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL) {
2746 stream_putc(s,
2747 BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL);
2748 stream_put(s, &attr->mp_nexthop_global,
2749 IPV6_MAX_BYTELEN);
2750 stream_put(s, &attr->mp_nexthop_local,
2751 IPV6_MAX_BYTELEN);
2752 } else {
2753 stream_putc(s, IPV6_MAX_BYTELEN);
2754 stream_put(s, &attr->mp_nexthop_global,
2755 IPV6_MAX_BYTELEN);
2756 }
2757 } break;
2758 case SAFI_MPLS_VPN: {
2759 if (attr->mp_nexthop_len
2760 == BGP_ATTR_NHLEN_IPV6_GLOBAL) {
2761 stream_putc(s, 24);
2762 stream_putl(s, 0); /* RD = 0, per RFC */
2763 stream_putl(s, 0);
2764 stream_put(s, &attr->mp_nexthop_global,
2765 IPV6_MAX_BYTELEN);
2766 } else if (attr->mp_nexthop_len
2767 == BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL) {
2768 stream_putc(s, 48);
2769 stream_putl(s, 0); /* RD = 0, per RFC */
2770 stream_putl(s, 0);
2771 stream_put(s, &attr->mp_nexthop_global,
2772 IPV6_MAX_BYTELEN);
2773 stream_putl(s, 0); /* RD = 0, per RFC */
2774 stream_putl(s, 0);
2775 stream_put(s, &attr->mp_nexthop_local,
2776 IPV6_MAX_BYTELEN);
2777 }
2778 } break;
2779 case SAFI_ENCAP:
2780 stream_putc(s, IPV6_MAX_BYTELEN);
2781 stream_put(s, &attr->mp_nexthop_global,
2782 IPV6_MAX_BYTELEN);
2783 break;
2784 case SAFI_FLOWSPEC:
2785 stream_putc(s, 0); /* no nexthop for flowspec */
2786 default:
2787 break;
2788 }
2789 break;
2790 default:
2791 if (safi != SAFI_FLOWSPEC)
2792 zlog_err(
2793 "Bad nexthop when sending to %s, AFI %u SAFI %u nhlen %d",
2794 peer->host, afi, safi, attr->mp_nexthop_len);
2795 break;
2796 }
2797
2798 /* SNPA */
2799 stream_putc(s, 0);
2800 return sizep;
2801 }
2802
2803 void bgp_packet_mpattr_prefix(struct stream *s, afi_t afi, safi_t safi,
2804 struct prefix *p, struct prefix_rd *prd,
2805 mpls_label_t *label, uint32_t num_labels,
2806 int addpath_encode, uint32_t addpath_tx_id,
2807 struct attr *attr)
2808 {
2809 if (safi == SAFI_MPLS_VPN) {
2810 if (addpath_encode)
2811 stream_putl(s, addpath_tx_id);
2812 /* Label, RD, Prefix write. */
2813 stream_putc(s, p->prefixlen + 88);
2814 stream_put(s, label, BGP_LABEL_BYTES);
2815 stream_put(s, prd->val, 8);
2816 stream_put(s, &p->u.prefix, PSIZE(p->prefixlen));
2817 } else if (afi == AFI_L2VPN && safi == SAFI_EVPN) {
2818 /* EVPN prefix - contents depend on type */
2819 bgp_evpn_encode_prefix(s, p, prd, label, num_labels, attr,
2820 addpath_encode, addpath_tx_id);
2821 } else if (safi == SAFI_LABELED_UNICAST) {
2822 /* Prefix write with label. */
2823 stream_put_labeled_prefix(s, p, label);
2824 } else if (safi == SAFI_FLOWSPEC) {
2825 if (PSIZE (p->prefixlen)+2 < FLOWSPEC_NLRI_SIZELIMIT)
2826 stream_putc(s, PSIZE (p->prefixlen)+2);
2827 else
2828 stream_putw(s, (PSIZE (p->prefixlen)+2)|(0xf<<12));
2829 stream_putc(s, 2);/* Filter type */
2830 stream_putc(s, p->prefixlen);/* Prefix length */
2831 stream_put(s, &p->u.prefix, PSIZE (p->prefixlen));
2832 } else
2833 stream_put_prefix_addpath(s, p, addpath_encode, addpath_tx_id);
2834 }
2835
2836 size_t bgp_packet_mpattr_prefix_size(afi_t afi, safi_t safi, struct prefix *p)
2837 {
2838 int size = PSIZE(p->prefixlen);
2839 if (safi == SAFI_MPLS_VPN)
2840 size += 88;
2841 else if (afi == AFI_L2VPN && safi == SAFI_EVPN)
2842 size += 232; // TODO: Maximum possible for type-2, type-3 and
2843 // type-5
2844 return size;
2845 }
2846
2847 /*
2848 * Encodes the tunnel encapsulation attribute,
2849 * and with ENABLE_BGP_VNC the VNC attribute which uses
2850 * almost the same TLV format
2851 */
2852 static void bgp_packet_mpattr_tea(struct bgp *bgp, struct peer *peer,
2853 struct stream *s, struct attr *attr,
2854 uint8_t attrtype)
2855 {
2856 unsigned int attrlenfield = 0;
2857 unsigned int attrhdrlen = 0;
2858 struct bgp_attr_encap_subtlv *subtlvs;
2859 struct bgp_attr_encap_subtlv *st;
2860 const char *attrname;
2861
2862 if (!attr || (attrtype == BGP_ATTR_ENCAP
2863 && (!attr->encap_tunneltype
2864 || attr->encap_tunneltype == BGP_ENCAP_TYPE_MPLS)))
2865 return;
2866
2867 switch (attrtype) {
2868 case BGP_ATTR_ENCAP:
2869 attrname = "Tunnel Encap";
2870 subtlvs = attr->encap_subtlvs;
2871 if (subtlvs == NULL) /* nothing to do */
2872 return;
2873 /*
2874 * The tunnel encap attr has an "outer" tlv.
2875 * T = tunneltype,
2876 * L = total length of subtlvs,
2877 * V = concatenated subtlvs.
2878 */
2879 attrlenfield = 2 + 2; /* T + L */
2880 attrhdrlen = 1 + 1; /* subTLV T + L */
2881 break;
2882
2883 #if ENABLE_BGP_VNC
2884 case BGP_ATTR_VNC:
2885 attrname = "VNC";
2886 subtlvs = attr->vnc_subtlvs;
2887 if (subtlvs == NULL) /* nothing to do */
2888 return;
2889 attrlenfield = 0; /* no outer T + L */
2890 attrhdrlen = 2 + 2; /* subTLV T + L */
2891 break;
2892 #endif
2893
2894 default:
2895 assert(0);
2896 }
2897
2898 /* compute attr length */
2899 for (st = subtlvs; st; st = st->next) {
2900 attrlenfield += (attrhdrlen + st->length);
2901 }
2902
2903 if (attrlenfield > 0xffff) {
2904 zlog_info("%s attribute is too long (length=%d), can't send it",
2905 attrname, attrlenfield);
2906 return;
2907 }
2908
2909 if (attrlenfield > 0xff) {
2910 /* 2-octet length field */
2911 stream_putc(s,
2912 BGP_ATTR_FLAG_TRANS | BGP_ATTR_FLAG_OPTIONAL
2913 | BGP_ATTR_FLAG_EXTLEN);
2914 stream_putc(s, attrtype);
2915 stream_putw(s, attrlenfield & 0xffff);
2916 } else {
2917 /* 1-octet length field */
2918 stream_putc(s, BGP_ATTR_FLAG_TRANS | BGP_ATTR_FLAG_OPTIONAL);
2919 stream_putc(s, attrtype);
2920 stream_putc(s, attrlenfield & 0xff);
2921 }
2922
2923 if (attrtype == BGP_ATTR_ENCAP) {
2924 /* write outer T+L */
2925 stream_putw(s, attr->encap_tunneltype);
2926 stream_putw(s, attrlenfield - 4);
2927 }
2928
2929 /* write each sub-tlv */
2930 for (st = subtlvs; st; st = st->next) {
2931 if (attrtype == BGP_ATTR_ENCAP) {
2932 stream_putc(s, st->type);
2933 stream_putc(s, st->length);
2934 #if ENABLE_BGP_VNC
2935 } else {
2936 stream_putw(s, st->type);
2937 stream_putw(s, st->length);
2938 #endif
2939 }
2940 stream_put(s, st->value, st->length);
2941 }
2942 }
2943
2944 void bgp_packet_mpattr_end(struct stream *s, size_t sizep)
2945 {
2946 /* Set MP attribute length. Don't count the (2) bytes used to encode
2947 the attr length */
2948 stream_putw_at(s, sizep, (stream_get_endp(s) - sizep) - 2);
2949 }
2950
2951 /* Make attribute packet. */
2952 bgp_size_t bgp_packet_attribute(struct bgp *bgp, struct peer *peer,
2953 struct stream *s, struct attr *attr,
2954 struct bpacket_attr_vec_arr *vecarr,
2955 struct prefix *p, afi_t afi, safi_t safi,
2956 struct peer *from, struct prefix_rd *prd,
2957 mpls_label_t *label, uint32_t num_labels,
2958 int addpath_encode, uint32_t addpath_tx_id)
2959 {
2960 size_t cp;
2961 size_t aspath_sizep;
2962 struct aspath *aspath;
2963 int send_as4_path = 0;
2964 int send_as4_aggregator = 0;
2965 int use32bit = (CHECK_FLAG(peer->cap, PEER_CAP_AS4_RCV)) ? 1 : 0;
2966
2967 if (!bgp)
2968 bgp = peer->bgp;
2969
2970 /* Remember current pointer. */
2971 cp = stream_get_endp(s);
2972
2973 if (p
2974 && !((afi == AFI_IP && safi == SAFI_UNICAST)
2975 && !peer_cap_enhe(peer, afi, safi))) {
2976 size_t mpattrlen_pos = 0;
2977
2978 mpattrlen_pos = bgp_packet_mpattr_start(s, peer, afi, safi,
2979 vecarr, attr);
2980 bgp_packet_mpattr_prefix(s, afi, safi, p, prd, label,
2981 num_labels, addpath_encode,
2982 addpath_tx_id, attr);
2983 bgp_packet_mpattr_end(s, mpattrlen_pos);
2984 }
2985
2986 /* Origin attribute. */
2987 stream_putc(s, BGP_ATTR_FLAG_TRANS);
2988 stream_putc(s, BGP_ATTR_ORIGIN);
2989 stream_putc(s, 1);
2990 stream_putc(s, attr->origin);
2991
2992 /* AS path attribute. */
2993
2994 /* If remote-peer is EBGP */
2995 if (peer->sort == BGP_PEER_EBGP
2996 && (!CHECK_FLAG(peer->af_flags[afi][safi],
2997 PEER_FLAG_AS_PATH_UNCHANGED)
2998 || attr->aspath->segments == NULL)
2999 && (!CHECK_FLAG(peer->af_flags[afi][safi],
3000 PEER_FLAG_RSERVER_CLIENT))) {
3001 aspath = aspath_dup(attr->aspath);
3002
3003 /* Even though we may not be configured for confederations we
3004 * may have
3005 * RXed an AS_PATH with AS_CONFED_SEQUENCE or AS_CONFED_SET */
3006 aspath = aspath_delete_confed_seq(aspath);
3007
3008 if (CHECK_FLAG(bgp->config, BGP_CONFIG_CONFEDERATION)) {
3009 /* Stuff our path CONFED_ID on the front */
3010 aspath = aspath_add_seq(aspath, bgp->confed_id);
3011 } else {
3012 if (peer->change_local_as) {
3013 /* If replace-as is specified, we only use the
3014 change_local_as when
3015 advertising routes. */
3016 if (!CHECK_FLAG(
3017 peer->flags,
3018 PEER_FLAG_LOCAL_AS_REPLACE_AS)) {
3019 aspath = aspath_add_seq(aspath,
3020 peer->local_as);
3021 }
3022 aspath = aspath_add_seq(aspath,
3023 peer->change_local_as);
3024 } else {
3025 aspath = aspath_add_seq(aspath, peer->local_as);
3026 }
3027 }
3028 } else if (peer->sort == BGP_PEER_CONFED) {
3029 /* A confed member, so we need to do the AS_CONFED_SEQUENCE
3030 * thing */
3031 aspath = aspath_dup(attr->aspath);
3032 aspath = aspath_add_confed_seq(aspath, peer->local_as);
3033 } else
3034 aspath = attr->aspath;
3035
3036 /* If peer is not AS4 capable, then:
3037 * - send the created AS_PATH out as AS4_PATH (optional, transitive),
3038 * but ensure that no AS_CONFED_SEQUENCE and AS_CONFED_SET path
3039 * segment
3040 * types are in it (i.e. exclude them if they are there)
3041 * AND do this only if there is at least one asnum > 65535 in the
3042 * path!
3043 * - send an AS_PATH out, but put 16Bit ASnums in it, not 32bit, and
3044 * change
3045 * all ASnums > 65535 to BGP_AS_TRANS
3046 */
3047
3048 stream_putc(s, BGP_ATTR_FLAG_TRANS | BGP_ATTR_FLAG_EXTLEN);
3049 stream_putc(s, BGP_ATTR_AS_PATH);
3050 aspath_sizep = stream_get_endp(s);
3051 stream_putw(s, 0);
3052 stream_putw_at(s, aspath_sizep, aspath_put(s, aspath, use32bit));
3053
3054 /* OLD session may need NEW_AS_PATH sent, if there are 4-byte ASNs
3055 * in the path
3056 */
3057 if (!use32bit && aspath_has_as4(aspath))
3058 send_as4_path =
3059 1; /* we'll do this later, at the correct place */
3060
3061 /* Nexthop attribute. */
3062 if (afi == AFI_IP && safi == SAFI_UNICAST
3063 && !peer_cap_enhe(peer, afi, safi)) {
3064 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_NEXT_HOP)) {
3065 stream_putc(s, BGP_ATTR_FLAG_TRANS);
3066 stream_putc(s, BGP_ATTR_NEXT_HOP);
3067 bpacket_attr_vec_arr_set_vec(vecarr, BGP_ATTR_VEC_NH, s,
3068 attr);
3069 stream_putc(s, 4);
3070 stream_put_ipv4(s, attr->nexthop.s_addr);
3071 } else if (peer_cap_enhe(from, afi, safi)) {
3072 /*
3073 * Likely this is the case when an IPv4 prefix was
3074 * received with
3075 * Extended Next-hop capability and now being advertised
3076 * to
3077 * non-ENHE peers.
3078 * Setting the mandatory (ipv4) next-hop attribute here
3079 * to enable
3080 * implicit next-hop self with correct (ipv4 address
3081 * family).
3082 */
3083 stream_putc(s, BGP_ATTR_FLAG_TRANS);
3084 stream_putc(s, BGP_ATTR_NEXT_HOP);
3085 bpacket_attr_vec_arr_set_vec(vecarr, BGP_ATTR_VEC_NH, s,
3086 NULL);
3087 stream_putc(s, 4);
3088 stream_put_ipv4(s, 0);
3089 }
3090 }
3091
3092 /* MED attribute. */
3093 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_MULTI_EXIT_DISC)
3094 || bgp->maxmed_active) {
3095 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL);
3096 stream_putc(s, BGP_ATTR_MULTI_EXIT_DISC);
3097 stream_putc(s, 4);
3098 stream_putl(s, (bgp->maxmed_active ? bgp->maxmed_value
3099 : attr->med));
3100 }
3101
3102 /* Local preference. */
3103 if (peer->sort == BGP_PEER_IBGP || peer->sort == BGP_PEER_CONFED) {
3104 stream_putc(s, BGP_ATTR_FLAG_TRANS);
3105 stream_putc(s, BGP_ATTR_LOCAL_PREF);
3106 stream_putc(s, 4);
3107 stream_putl(s, attr->local_pref);
3108 }
3109
3110 /* Atomic aggregate. */
3111 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_ATOMIC_AGGREGATE)) {
3112 stream_putc(s, BGP_ATTR_FLAG_TRANS);
3113 stream_putc(s, BGP_ATTR_ATOMIC_AGGREGATE);
3114 stream_putc(s, 0);
3115 }
3116
3117 /* Aggregator. */
3118 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_AGGREGATOR)) {
3119 /* Common to BGP_ATTR_AGGREGATOR, regardless of ASN size */
3120 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS);
3121 stream_putc(s, BGP_ATTR_AGGREGATOR);
3122
3123 if (use32bit) {
3124 /* AS4 capable peer */
3125 stream_putc(s, 8);
3126 stream_putl(s, attr->aggregator_as);
3127 } else {
3128 /* 2-byte AS peer */
3129 stream_putc(s, 6);
3130
3131 /* Is ASN representable in 2-bytes? Or must AS_TRANS be
3132 * used? */
3133 if (attr->aggregator_as > 65535) {
3134 stream_putw(s, BGP_AS_TRANS);
3135
3136 /* we have to send AS4_AGGREGATOR, too.
3137 * we'll do that later in order to send
3138 * attributes in ascending
3139 * order.
3140 */
3141 send_as4_aggregator = 1;
3142 } else
3143 stream_putw(s, (uint16_t)attr->aggregator_as);
3144 }
3145 stream_put_ipv4(s, attr->aggregator_addr.s_addr);
3146 }
3147
3148 /* Community attribute. */
3149 if (CHECK_FLAG(peer->af_flags[afi][safi], PEER_FLAG_SEND_COMMUNITY)
3150 && (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_COMMUNITIES))) {
3151 if (attr->community->size * 4 > 255) {
3152 stream_putc(s,
3153 BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS
3154 | BGP_ATTR_FLAG_EXTLEN);
3155 stream_putc(s, BGP_ATTR_COMMUNITIES);
3156 stream_putw(s, attr->community->size * 4);
3157 } else {
3158 stream_putc(s,
3159 BGP_ATTR_FLAG_OPTIONAL
3160 | BGP_ATTR_FLAG_TRANS);
3161 stream_putc(s, BGP_ATTR_COMMUNITIES);
3162 stream_putc(s, attr->community->size * 4);
3163 }
3164 stream_put(s, attr->community->val, attr->community->size * 4);
3165 }
3166
3167 /*
3168 * Large Community attribute.
3169 */
3170 if (CHECK_FLAG(peer->af_flags[afi][safi],
3171 PEER_FLAG_SEND_LARGE_COMMUNITY)
3172 && (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_LARGE_COMMUNITIES))) {
3173 if (lcom_length(attr->lcommunity) > 255) {
3174 stream_putc(s,
3175 BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS
3176 | BGP_ATTR_FLAG_EXTLEN);
3177 stream_putc(s, BGP_ATTR_LARGE_COMMUNITIES);
3178 stream_putw(s, lcom_length(attr->lcommunity));
3179 } else {
3180 stream_putc(s,
3181 BGP_ATTR_FLAG_OPTIONAL
3182 | BGP_ATTR_FLAG_TRANS);
3183 stream_putc(s, BGP_ATTR_LARGE_COMMUNITIES);
3184 stream_putc(s, lcom_length(attr->lcommunity));
3185 }
3186 stream_put(s, attr->lcommunity->val,
3187 lcom_length(attr->lcommunity));
3188 }
3189
3190 /* Route Reflector. */
3191 if (peer->sort == BGP_PEER_IBGP && from
3192 && from->sort == BGP_PEER_IBGP) {
3193 /* Originator ID. */
3194 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL);
3195 stream_putc(s, BGP_ATTR_ORIGINATOR_ID);
3196 stream_putc(s, 4);
3197
3198 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_ORIGINATOR_ID))
3199 stream_put_in_addr(s, &attr->originator_id);
3200 else
3201 stream_put_in_addr(s, &from->remote_id);
3202
3203 /* Cluster list. */
3204 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL);
3205 stream_putc(s, BGP_ATTR_CLUSTER_LIST);
3206
3207 if (attr->cluster) {
3208 stream_putc(s, attr->cluster->length + 4);
3209 /* If this peer configuration's parent BGP has
3210 * cluster_id. */
3211 if (bgp->config & BGP_CONFIG_CLUSTER_ID)
3212 stream_put_in_addr(s, &bgp->cluster_id);
3213 else
3214 stream_put_in_addr(s, &bgp->router_id);
3215 stream_put(s, attr->cluster->list,
3216 attr->cluster->length);
3217 } else {
3218 stream_putc(s, 4);
3219 /* If this peer configuration's parent BGP has
3220 * cluster_id. */
3221 if (bgp->config & BGP_CONFIG_CLUSTER_ID)
3222 stream_put_in_addr(s, &bgp->cluster_id);
3223 else
3224 stream_put_in_addr(s, &bgp->router_id);
3225 }
3226 }
3227
3228 /* Extended Communities attribute. */
3229 if (CHECK_FLAG(peer->af_flags[afi][safi], PEER_FLAG_SEND_EXT_COMMUNITY)
3230 && (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_EXT_COMMUNITIES))) {
3231 if (peer->sort == BGP_PEER_IBGP
3232 || peer->sort == BGP_PEER_CONFED) {
3233 if (attr->ecommunity->size * 8 > 255) {
3234 stream_putc(s,
3235 BGP_ATTR_FLAG_OPTIONAL
3236 | BGP_ATTR_FLAG_TRANS
3237 | BGP_ATTR_FLAG_EXTLEN);
3238 stream_putc(s, BGP_ATTR_EXT_COMMUNITIES);
3239 stream_putw(s, attr->ecommunity->size * 8);
3240 } else {
3241 stream_putc(s,
3242 BGP_ATTR_FLAG_OPTIONAL
3243 | BGP_ATTR_FLAG_TRANS);
3244 stream_putc(s, BGP_ATTR_EXT_COMMUNITIES);
3245 stream_putc(s, attr->ecommunity->size * 8);
3246 }
3247 stream_put(s, attr->ecommunity->val,
3248 attr->ecommunity->size * 8);
3249 } else {
3250 uint8_t *pnt;
3251 int tbit;
3252 int ecom_tr_size = 0;
3253 int i;
3254
3255 for (i = 0; i < attr->ecommunity->size; i++) {
3256 pnt = attr->ecommunity->val + (i * 8);
3257 tbit = *pnt;
3258
3259 if (CHECK_FLAG(tbit,
3260 ECOMMUNITY_FLAG_NON_TRANSITIVE))
3261 continue;
3262
3263 ecom_tr_size++;
3264 }
3265
3266 if (ecom_tr_size) {
3267 if (ecom_tr_size * 8 > 255) {
3268 stream_putc(
3269 s,
3270 BGP_ATTR_FLAG_OPTIONAL
3271 | BGP_ATTR_FLAG_TRANS
3272 | BGP_ATTR_FLAG_EXTLEN);
3273 stream_putc(s,
3274 BGP_ATTR_EXT_COMMUNITIES);
3275 stream_putw(s, ecom_tr_size * 8);
3276 } else {
3277 stream_putc(
3278 s,
3279 BGP_ATTR_FLAG_OPTIONAL
3280 | BGP_ATTR_FLAG_TRANS);
3281 stream_putc(s,
3282 BGP_ATTR_EXT_COMMUNITIES);
3283 stream_putc(s, ecom_tr_size * 8);
3284 }
3285
3286 for (i = 0; i < attr->ecommunity->size; i++) {
3287 pnt = attr->ecommunity->val + (i * 8);
3288 tbit = *pnt;
3289
3290 if (CHECK_FLAG(
3291 tbit,
3292 ECOMMUNITY_FLAG_NON_TRANSITIVE))
3293 continue;
3294
3295 stream_put(s, pnt, 8);
3296 }
3297 }
3298 }
3299 }
3300
3301 /* Label index attribute. */
3302 if (safi == SAFI_LABELED_UNICAST) {
3303 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_PREFIX_SID)) {
3304 uint32_t label_index;
3305
3306 label_index = attr->label_index;
3307
3308 if (label_index != BGP_INVALID_LABEL_INDEX) {
3309 stream_putc(s,
3310 BGP_ATTR_FLAG_OPTIONAL
3311 | BGP_ATTR_FLAG_TRANS);
3312 stream_putc(s, BGP_ATTR_PREFIX_SID);
3313 stream_putc(s, 10);
3314 stream_putc(s, BGP_PREFIX_SID_LABEL_INDEX);
3315 stream_putw(s,
3316 BGP_PREFIX_SID_LABEL_INDEX_LENGTH);
3317 stream_putc(s, 0); // reserved
3318 stream_putw(s, 0); // flags
3319 stream_putl(s, label_index);
3320 }
3321 }
3322 }
3323
3324 if (send_as4_path) {
3325 /* If the peer is NOT As4 capable, AND */
3326 /* there are ASnums > 65535 in path THEN
3327 * give out AS4_PATH */
3328
3329 /* Get rid of all AS_CONFED_SEQUENCE and AS_CONFED_SET
3330 * path segments!
3331 * Hm, I wonder... confederation things *should* only be at
3332 * the beginning of an aspath, right? Then we should use
3333 * aspath_delete_confed_seq for this, because it is already
3334 * there! (JK)
3335 * Folks, talk to me: what is reasonable here!?
3336 */
3337 aspath = aspath_delete_confed_seq(aspath);
3338
3339 stream_putc(s,
3340 BGP_ATTR_FLAG_TRANS | BGP_ATTR_FLAG_OPTIONAL
3341 | BGP_ATTR_FLAG_EXTLEN);
3342 stream_putc(s, BGP_ATTR_AS4_PATH);
3343 aspath_sizep = stream_get_endp(s);
3344 stream_putw(s, 0);
3345 stream_putw_at(s, aspath_sizep, aspath_put(s, aspath, 1));
3346 }
3347
3348 if (aspath != attr->aspath)
3349 aspath_free(aspath);
3350
3351 if (send_as4_aggregator) {
3352 /* send AS4_AGGREGATOR, at this place */
3353 /* this section of code moved here in order to ensure the
3354 * correct
3355 * *ascending* order of attributes
3356 */
3357 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS);
3358 stream_putc(s, BGP_ATTR_AS4_AGGREGATOR);
3359 stream_putc(s, 8);
3360 stream_putl(s, attr->aggregator_as);
3361 stream_put_ipv4(s, attr->aggregator_addr.s_addr);
3362 }
3363
3364 if (((afi == AFI_IP || afi == AFI_IP6)
3365 && (safi == SAFI_ENCAP || safi == SAFI_MPLS_VPN))
3366 || (afi == AFI_L2VPN && safi == SAFI_EVPN)) {
3367 /* Tunnel Encap attribute */
3368 bgp_packet_mpattr_tea(bgp, peer, s, attr, BGP_ATTR_ENCAP);
3369
3370 #if ENABLE_BGP_VNC
3371 /* VNC attribute */
3372 bgp_packet_mpattr_tea(bgp, peer, s, attr, BGP_ATTR_VNC);
3373 #endif
3374 }
3375
3376 /* PMSI Tunnel */
3377 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_PMSI_TUNNEL)) {
3378 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS);
3379 stream_putc(s, BGP_ATTR_PMSI_TUNNEL);
3380 stream_putc(s, 9); // Length
3381 stream_putc(s, 0); // Flags
3382 stream_putc(s, PMSI_TNLTYPE_INGR_REPL); // IR (6)
3383 stream_put(s, &(attr->label),
3384 BGP_LABEL_BYTES); // MPLS Label / VXLAN VNI
3385 stream_put_ipv4(s, attr->nexthop.s_addr);
3386 // Unicast tunnel endpoint IP address
3387 }
3388
3389 /* Unknown transit attribute. */
3390 if (attr->transit)
3391 stream_put(s, attr->transit->val, attr->transit->length);
3392
3393 /* Return total size of attribute. */
3394 return stream_get_endp(s) - cp;
3395 }
3396
3397 size_t bgp_packet_mpunreach_start(struct stream *s, afi_t afi, safi_t safi)
3398 {
3399 unsigned long attrlen_pnt;
3400 iana_afi_t pkt_afi;
3401 iana_safi_t pkt_safi;
3402
3403 /* Set extended bit always to encode the attribute length as 2 bytes */
3404 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_EXTLEN);
3405 stream_putc(s, BGP_ATTR_MP_UNREACH_NLRI);
3406
3407 attrlen_pnt = stream_get_endp(s);
3408 stream_putw(s, 0); /* Length of this attribute. */
3409
3410 /* Convert AFI, SAFI to values for packet. */
3411 bgp_map_afi_safi_int2iana(afi, safi, &pkt_afi, &pkt_safi);
3412
3413 stream_putw(s, pkt_afi);
3414 stream_putc(s, pkt_safi);
3415
3416 return attrlen_pnt;
3417 }
3418
3419 void bgp_packet_mpunreach_prefix(struct stream *s, struct prefix *p, afi_t afi,
3420 safi_t safi, struct prefix_rd *prd,
3421 mpls_label_t *label, uint32_t num_labels,
3422 int addpath_encode, uint32_t addpath_tx_id,
3423 struct attr *attr)
3424 {
3425 uint8_t wlabel[3] = {0x80, 0x00, 0x00};
3426
3427 if (safi == SAFI_LABELED_UNICAST) {
3428 label = (mpls_label_t *)wlabel;
3429 num_labels = 1;
3430 }
3431
3432 return bgp_packet_mpattr_prefix(s, afi, safi, p, prd, label, num_labels,
3433 addpath_encode, addpath_tx_id, attr);
3434 }
3435
3436 void bgp_packet_mpunreach_end(struct stream *s, size_t attrlen_pnt)
3437 {
3438 bgp_packet_mpattr_end(s, attrlen_pnt);
3439 }
3440
3441 /* Initialization of attribute. */
3442 void bgp_attr_init(void)
3443 {
3444 aspath_init();
3445 attrhash_init();
3446 community_init();
3447 ecommunity_init();
3448 lcommunity_init();
3449 cluster_init();
3450 transit_init();
3451 encap_init();
3452 }
3453
3454 void bgp_attr_finish(void)
3455 {
3456 aspath_finish();
3457 attrhash_finish();
3458 community_finish();
3459 ecommunity_finish();
3460 lcommunity_finish();
3461 cluster_finish();
3462 transit_finish();
3463 encap_finish();
3464 }
3465
3466 /* Make attribute packet. */
3467 void bgp_dump_routes_attr(struct stream *s, struct attr *attr,
3468 struct prefix *prefix)
3469 {
3470 unsigned long cp;
3471 unsigned long len;
3472 size_t aspath_lenp;
3473 struct aspath *aspath;
3474 int addpath_encode = 0;
3475 uint32_t addpath_tx_id = 0;
3476
3477 /* Remember current pointer. */
3478 cp = stream_get_endp(s);
3479
3480 /* Place holder of length. */
3481 stream_putw(s, 0);
3482
3483 /* Origin attribute. */
3484 stream_putc(s, BGP_ATTR_FLAG_TRANS);
3485 stream_putc(s, BGP_ATTR_ORIGIN);
3486 stream_putc(s, 1);
3487 stream_putc(s, attr->origin);
3488
3489 aspath = attr->aspath;
3490
3491 stream_putc(s, BGP_ATTR_FLAG_TRANS | BGP_ATTR_FLAG_EXTLEN);
3492 stream_putc(s, BGP_ATTR_AS_PATH);
3493 aspath_lenp = stream_get_endp(s);
3494 stream_putw(s, 0);
3495
3496 stream_putw_at(s, aspath_lenp, aspath_put(s, aspath, 1));
3497
3498 /* Nexthop attribute. */
3499 /* If it's an IPv6 prefix, don't dump the IPv4 nexthop to save space */
3500 if (prefix != NULL && prefix->family != AF_INET6) {
3501 stream_putc(s, BGP_ATTR_FLAG_TRANS);
3502 stream_putc(s, BGP_ATTR_NEXT_HOP);
3503 stream_putc(s, 4);
3504 stream_put_ipv4(s, attr->nexthop.s_addr);
3505 }
3506
3507 /* MED attribute. */
3508 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_MULTI_EXIT_DISC)) {
3509 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL);
3510 stream_putc(s, BGP_ATTR_MULTI_EXIT_DISC);
3511 stream_putc(s, 4);
3512 stream_putl(s, attr->med);
3513 }
3514
3515 /* Local preference. */
3516 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_LOCAL_PREF)) {
3517 stream_putc(s, BGP_ATTR_FLAG_TRANS);
3518 stream_putc(s, BGP_ATTR_LOCAL_PREF);
3519 stream_putc(s, 4);
3520 stream_putl(s, attr->local_pref);
3521 }
3522
3523 /* Atomic aggregate. */
3524 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_ATOMIC_AGGREGATE)) {
3525 stream_putc(s, BGP_ATTR_FLAG_TRANS);
3526 stream_putc(s, BGP_ATTR_ATOMIC_AGGREGATE);
3527 stream_putc(s, 0);
3528 }
3529
3530 /* Aggregator. */
3531 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_AGGREGATOR)) {
3532 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS);
3533 stream_putc(s, BGP_ATTR_AGGREGATOR);
3534 stream_putc(s, 8);
3535 stream_putl(s, attr->aggregator_as);
3536 stream_put_ipv4(s, attr->aggregator_addr.s_addr);
3537 }
3538
3539 /* Community attribute. */
3540 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_COMMUNITIES)) {
3541 if (attr->community->size * 4 > 255) {
3542 stream_putc(s,
3543 BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS
3544 | BGP_ATTR_FLAG_EXTLEN);
3545 stream_putc(s, BGP_ATTR_COMMUNITIES);
3546 stream_putw(s, attr->community->size * 4);
3547 } else {
3548 stream_putc(s,
3549 BGP_ATTR_FLAG_OPTIONAL
3550 | BGP_ATTR_FLAG_TRANS);
3551 stream_putc(s, BGP_ATTR_COMMUNITIES);
3552 stream_putc(s, attr->community->size * 4);
3553 }
3554 stream_put(s, attr->community->val, attr->community->size * 4);
3555 }
3556
3557 /* Large Community attribute. */
3558 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_LARGE_COMMUNITIES)) {
3559 if (lcom_length(attr->lcommunity) > 255) {
3560 stream_putc(s,
3561 BGP_ATTR_FLAG_OPTIONAL | BGP_ATTR_FLAG_TRANS
3562 | BGP_ATTR_FLAG_EXTLEN);
3563 stream_putc(s, BGP_ATTR_LARGE_COMMUNITIES);
3564 stream_putw(s, lcom_length(attr->lcommunity));
3565 } else {
3566 stream_putc(s,
3567 BGP_ATTR_FLAG_OPTIONAL
3568 | BGP_ATTR_FLAG_TRANS);
3569 stream_putc(s, BGP_ATTR_LARGE_COMMUNITIES);
3570 stream_putc(s, lcom_length(attr->lcommunity));
3571 }
3572
3573 stream_put(s, attr->lcommunity->val,
3574 lcom_length(attr->lcommunity));
3575 }
3576
3577 /* Add a MP_NLRI attribute to dump the IPv6 next hop */
3578 if (prefix != NULL && prefix->family == AF_INET6
3579 && (attr->mp_nexthop_len == BGP_ATTR_NHLEN_IPV6_GLOBAL
3580 || attr->mp_nexthop_len == BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL)) {
3581 int sizep;
3582
3583 stream_putc(s, BGP_ATTR_FLAG_OPTIONAL);
3584 stream_putc(s, BGP_ATTR_MP_REACH_NLRI);
3585 sizep = stream_get_endp(s);
3586
3587 /* MP header */
3588 stream_putc(s, 0); /* Marker: Attribute length. */
3589 stream_putw(s, AFI_IP6); /* AFI */
3590 stream_putc(s, SAFI_UNICAST); /* SAFI */
3591
3592 /* Next hop */
3593 stream_putc(s, attr->mp_nexthop_len);
3594 stream_put(s, &attr->mp_nexthop_global, IPV6_MAX_BYTELEN);
3595 if (attr->mp_nexthop_len == BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL)
3596 stream_put(s, &attr->mp_nexthop_local,
3597 IPV6_MAX_BYTELEN);
3598
3599 /* SNPA */
3600 stream_putc(s, 0);
3601
3602 /* Prefix */
3603 stream_put_prefix_addpath(s, prefix, addpath_encode,
3604 addpath_tx_id);
3605
3606 /* Set MP attribute length. */
3607 stream_putc_at(s, sizep, (stream_get_endp(s) - sizep) - 1);
3608 }
3609
3610 /* Prefix SID */
3611 if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_PREFIX_SID)) {
3612 if (attr->label_index != BGP_INVALID_LABEL_INDEX) {
3613 stream_putc(s,
3614 BGP_ATTR_FLAG_OPTIONAL
3615 | BGP_ATTR_FLAG_TRANS);
3616 stream_putc(s, BGP_ATTR_PREFIX_SID);
3617 stream_putc(s, 10);
3618 stream_putc(s, BGP_PREFIX_SID_LABEL_INDEX);
3619 stream_putc(s, BGP_PREFIX_SID_LABEL_INDEX_LENGTH);
3620 stream_putc(s, 0); // reserved
3621 stream_putw(s, 0); // flags
3622 stream_putl(s, attr->label_index);
3623 }
3624 }
3625
3626 /* Return total size of attribute. */
3627 len = stream_get_endp(s) - cp - 2;
3628 stream_putw_at(s, cp, len);
3629 }
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