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718e3744 | 1 | /* AS path management routines. |
896014f4 DL |
2 | * Copyright (C) 1996, 97, 98, 99 Kunihiro Ishiguro |
3 | * Copyright (C) 2005 Sun Microsystems, Inc. | |
4 | * | |
5 | * This file is part of GNU Zebra. | |
6 | * | |
7 | * GNU Zebra is free software; you can redistribute it and/or modify it | |
8 | * under the terms of the GNU General Public License as published by the | |
9 | * Free Software Foundation; either version 2, or (at your option) any | |
10 | * later version. | |
11 | * | |
12 | * GNU Zebra is distributed in the hope that it will be useful, but | |
13 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
15 | * General Public License for more details. | |
16 | * | |
17 | * You should have received a copy of the GNU General Public License along | |
18 | * with this program; see the file COPYING; if not, write to the Free Software | |
19 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
20 | */ | |
718e3744 | 21 | |
22 | #include <zebra.h> | |
23 | ||
24 | #include "hash.h" | |
25 | #include "memory.h" | |
26 | #include "vector.h" | |
718e3744 | 27 | #include "log.h" |
fe69a505 | 28 | #include "stream.h" |
4dcadbef | 29 | #include "command.h" |
0b2aa3a0 | 30 | #include "jhash.h" |
3f9c7369 | 31 | #include "queue.h" |
039f3a34 | 32 | #include "filter.h" |
718e3744 | 33 | |
34 | #include "bgpd/bgpd.h" | |
35 | #include "bgpd/bgp_aspath.h" | |
0b2aa3a0 PJ |
36 | #include "bgpd/bgp_debug.h" |
37 | #include "bgpd/bgp_attr.h" | |
559aaa30 | 38 | #include "bgpd/bgp_errors.h" |
6b0655a2 | 39 | |
718e3744 | 40 | /* Attr. Flags and Attr. Type Code. */ |
ade6974d | 41 | #define AS_HEADER_SIZE 2 |
718e3744 | 42 | |
0b2aa3a0 | 43 | /* Now FOUR octets are used for AS value. */ |
718e3744 | 44 | #define AS_VALUE_SIZE sizeof (as_t) |
0b2aa3a0 PJ |
45 | /* This is the old one */ |
46 | #define AS16_VALUE_SIZE sizeof (as16_t) | |
718e3744 | 47 | |
fe69a505 | 48 | /* Maximum protocol segment length value */ |
49 | #define AS_SEGMENT_MAX 255 | |
50 | ||
51 | /* The following length and size macros relate specifically to Quagga's | |
52 | * internal representation of AS-Segments, not per se to the on-wire | |
53 | * sizes and lengths. At present (200508) they sort of match, however | |
54 | * the ONLY functions which should now about the on-wire syntax are | |
55 | * aspath_put, assegment_put and assegment_parse. | |
0b2aa3a0 PJ |
56 | * |
57 | * aspath_put returns bytes written, the only definitive record of | |
58 | * size of wire-format attribute.. | |
fe69a505 | 59 | */ |
60 | ||
61 | /* Calculated size in bytes of ASN segment data to hold N ASN's */ | |
d62a17ae | 62 | #define ASSEGMENT_DATA_SIZE(N, S) \ |
63 | ((N) * ((S) ? AS_VALUE_SIZE : AS16_VALUE_SIZE)) | |
718e3744 | 64 | |
fe69a505 | 65 | /* Calculated size of segment struct to hold N ASN's */ |
0b2aa3a0 | 66 | #define ASSEGMENT_SIZE(N,S) (AS_HEADER_SIZE + ASSEGMENT_DATA_SIZE (N,S)) |
fe69a505 | 67 | |
68 | /* AS segment octet length. */ | |
0b2aa3a0 | 69 | #define ASSEGMENT_LEN(X,S) ASSEGMENT_SIZE((X)->length,S) |
fe69a505 | 70 | |
71 | /* AS_SEQUENCE segments can be packed together */ | |
72 | /* Can the types of X and Y be considered for packing? */ | |
d62a17ae | 73 | #define ASSEGMENT_TYPES_PACKABLE(X, Y) \ |
74 | (((X)->type == (Y)->type) && ((X)->type == AS_SEQUENCE)) | |
fe69a505 | 75 | /* Types and length of X,Y suitable for packing? */ |
d62a17ae | 76 | #define ASSEGMENTS_PACKABLE(X, Y) \ |
77 | (ASSEGMENT_TYPES_PACKABLE((X), (Y)) \ | |
78 | && (((X)->length + (Y)->length) <= AS_SEGMENT_MAX)) | |
fe69a505 | 79 | |
d62a17ae | 80 | /* As segment header - the on-wire representation |
fe69a505 | 81 | * NOT the internal representation! |
82 | */ | |
d62a17ae | 83 | struct assegment_header { |
d7c0a89a QY |
84 | uint8_t type; |
85 | uint8_t length; | |
718e3744 | 86 | }; |
87 | ||
88 | /* Hash for aspath. This is the top level structure of AS path. */ | |
da88ea82 | 89 | static struct hash *ashash; |
8fdc32ab | 90 | |
91 | /* Stream for SNMP. See aspath_snmp_pathseg */ | |
92 | static struct stream *snmp_stream; | |
6b0655a2 | 93 | |
f669f7d2 | 94 | /* Callers are required to initialize the memory */ |
d62a17ae | 95 | static as_t *assegment_data_new(int num) |
fe69a505 | 96 | { |
d62a17ae | 97 | return (XMALLOC(MTYPE_AS_SEG_DATA, ASSEGMENT_DATA_SIZE(num, 1))); |
fe69a505 | 98 | } |
99 | ||
d62a17ae | 100 | static void assegment_data_free(as_t *asdata) |
289d2501 | 101 | { |
d62a17ae | 102 | XFREE(MTYPE_AS_SEG_DATA, asdata); |
289d2501 LB |
103 | } |
104 | ||
2b64873d DL |
105 | const char *const aspath_segment_type_str[] = { |
106 | "as-invalid", "as-set", "as-sequence", "as-confed-sequence", | |
107 | "as-confed-set" | |
108 | }; | |
f1aa5d8a | 109 | |
fe69a505 | 110 | /* Get a new segment. Note that 0 is an allowed length, |
111 | * and will result in a segment with no allocated data segment. | |
112 | * the caller should immediately assign data to the segment, as the segment | |
113 | * otherwise is not generally valid | |
114 | */ | |
d7c0a89a | 115 | static struct assegment *assegment_new(uint8_t type, unsigned short length) |
d62a17ae | 116 | { |
117 | struct assegment *new; | |
118 | ||
119 | new = XCALLOC(MTYPE_AS_SEG, sizeof(struct assegment)); | |
120 | ||
121 | if (length) | |
122 | new->as = assegment_data_new(length); | |
123 | ||
124 | new->length = length; | |
125 | new->type = type; | |
126 | ||
127 | return new; | |
128 | } | |
129 | ||
130 | static void assegment_free(struct assegment *seg) | |
131 | { | |
132 | if (!seg) | |
133 | return; | |
134 | ||
135 | if (seg->as) | |
136 | assegment_data_free(seg->as); | |
137 | memset(seg, 0xfe, sizeof(struct assegment)); | |
138 | XFREE(MTYPE_AS_SEG, seg); | |
139 | ||
140 | return; | |
fe69a505 | 141 | } |
142 | ||
143 | /* free entire chain of segments */ | |
d62a17ae | 144 | static void assegment_free_all(struct assegment *seg) |
fe69a505 | 145 | { |
d62a17ae | 146 | struct assegment *prev; |
147 | ||
148 | while (seg) { | |
149 | prev = seg; | |
150 | seg = seg->next; | |
151 | assegment_free(prev); | |
152 | } | |
fe69a505 | 153 | } |
154 | ||
155 | /* Duplicate just the given assegment and its data */ | |
d62a17ae | 156 | static struct assegment *assegment_dup(struct assegment *seg) |
fe69a505 | 157 | { |
d62a17ae | 158 | struct assegment *new; |
159 | ||
160 | new = assegment_new(seg->type, seg->length); | |
161 | memcpy(new->as, seg->as, ASSEGMENT_DATA_SIZE(new->length, 1)); | |
162 | ||
163 | return new; | |
fe69a505 | 164 | } |
165 | ||
166 | /* Duplicate entire chain of assegments, return the head */ | |
d62a17ae | 167 | static struct assegment *assegment_dup_all(struct assegment *seg) |
168 | { | |
169 | struct assegment *new = NULL; | |
170 | struct assegment *head = NULL; | |
171 | ||
172 | while (seg) { | |
173 | if (head) { | |
174 | new->next = assegment_dup(seg); | |
175 | new = new->next; | |
176 | } else | |
177 | head = new = assegment_dup(seg); | |
178 | ||
179 | seg = seg->next; | |
180 | } | |
181 | return head; | |
fe69a505 | 182 | } |
183 | ||
184 | /* prepend the as number to given segment, given num of times */ | |
d62a17ae | 185 | static struct assegment *assegment_prepend_asns(struct assegment *seg, |
186 | as_t asnum, int num) | |
fe69a505 | 187 | { |
d62a17ae | 188 | as_t *newas; |
189 | int i; | |
fe69a505 | 190 | |
d62a17ae | 191 | if (!num) |
192 | return seg; | |
f669f7d2 | 193 | |
d62a17ae | 194 | if (num >= AS_SEGMENT_MAX) |
195 | return seg; /* we don't do huge prepends */ | |
f669f7d2 | 196 | |
d62a17ae | 197 | if ((newas = assegment_data_new(seg->length + num)) == NULL) |
198 | return seg; | |
199 | ||
200 | for (i = 0; i < num; i++) | |
201 | newas[i] = asnum; | |
202 | ||
203 | memcpy(newas + num, seg->as, ASSEGMENT_DATA_SIZE(seg->length, 1)); | |
204 | assegment_data_free(seg->as); | |
205 | seg->as = newas; | |
206 | seg->length += num; | |
207 | ||
208 | return seg; | |
fe69a505 | 209 | } |
210 | ||
211 | /* append given array of as numbers to the segment */ | |
d62a17ae | 212 | static struct assegment *assegment_append_asns(struct assegment *seg, |
213 | as_t *asnos, int num) | |
fe69a505 | 214 | { |
d62a17ae | 215 | as_t *newas; |
fe69a505 | 216 | |
e00d8008 NT |
217 | if (!seg) |
218 | return seg; | |
219 | ||
d62a17ae | 220 | newas = XREALLOC(MTYPE_AS_SEG_DATA, seg->as, |
221 | ASSEGMENT_DATA_SIZE(seg->length + num, 1)); | |
222 | ||
0ce1ca80 DS |
223 | seg->as = newas; |
224 | memcpy(seg->as + seg->length, asnos, | |
225 | ASSEGMENT_DATA_SIZE(num, 1)); | |
226 | seg->length += num; | |
227 | return seg; | |
fe69a505 | 228 | } |
229 | ||
d62a17ae | 230 | static int int_cmp(const void *p1, const void *p2) |
fe69a505 | 231 | { |
d62a17ae | 232 | const as_t *as1 = p1; |
233 | const as_t *as2 = p2; | |
234 | ||
235 | return (*as1 == *as2) ? 0 : ((*as1 > *as2) ? 1 : -1); | |
fe69a505 | 236 | } |
237 | ||
238 | /* normalise the segment. | |
239 | * In particular, merge runs of AS_SEQUENCEs into one segment | |
240 | * Internally, we do not care about the wire segment length limit, and | |
241 | * we want each distinct AS_PATHs to have the exact same internal | |
242 | * representation - eg, so that our hashing actually works.. | |
243 | */ | |
d62a17ae | 244 | static struct assegment *assegment_normalise(struct assegment *head) |
245 | { | |
246 | struct assegment *seg = head, *pin; | |
247 | struct assegment *tmp; | |
248 | ||
249 | if (!head) | |
250 | return head; | |
251 | ||
252 | while (seg) { | |
253 | pin = seg; | |
254 | ||
255 | /* Sort values SET segments, for determinism in paths to aid | |
256 | * creation of hash values / path comparisons | |
257 | * and because it helps other lesser implementations ;) | |
258 | */ | |
259 | if (seg->type == AS_SET || seg->type == AS_CONFED_SET) { | |
260 | int tail = 0; | |
261 | int i; | |
262 | ||
263 | qsort(seg->as, seg->length, sizeof(as_t), int_cmp); | |
264 | ||
265 | /* weed out dupes */ | |
266 | for (i = 1; i < seg->length; i++) { | |
267 | if (seg->as[tail] == seg->as[i]) | |
268 | continue; | |
269 | ||
270 | tail++; | |
271 | if (tail < i) | |
272 | seg->as[tail] = seg->as[i]; | |
273 | } | |
274 | /* seg->length can be 0.. */ | |
275 | if (seg->length) | |
276 | seg->length = tail + 1; | |
277 | } | |
278 | ||
279 | /* read ahead from the current, pinned segment while the | |
280 | * segments | |
281 | * are packable/mergeable. Append all following packable | |
282 | * segments | |
283 | * to the segment we have pinned and remove these appended | |
284 | * segments. | |
285 | */ | |
286 | while (pin->next && ASSEGMENT_TYPES_PACKABLE(pin, pin->next)) { | |
287 | tmp = pin->next; | |
288 | seg = pin->next; | |
289 | ||
290 | /* append the next sequence to the pinned sequence */ | |
291 | pin = assegment_append_asns(pin, seg->as, seg->length); | |
292 | ||
293 | /* bypass the next sequence */ | |
294 | pin->next = seg->next; | |
295 | ||
296 | /* get rid of the now referenceless segment */ | |
297 | assegment_free(tmp); | |
298 | } | |
299 | ||
300 | seg = pin->next; | |
0b2aa3a0 | 301 | } |
d62a17ae | 302 | return head; |
718e3744 | 303 | } |
304 | ||
d62a17ae | 305 | static struct aspath *aspath_new(void) |
718e3744 | 306 | { |
d62a17ae | 307 | return XCALLOC(MTYPE_AS_PATH, sizeof(struct aspath)); |
308 | } | |
f1aa5d8a | 309 | |
d62a17ae | 310 | /* Free AS path structure. */ |
311 | void aspath_free(struct aspath *aspath) | |
312 | { | |
313 | if (!aspath) | |
314 | return; | |
315 | if (aspath->segments) | |
316 | assegment_free_all(aspath->segments); | |
0a22ddfb | 317 | XFREE(MTYPE_AS_STR, aspath->str); |
d62a17ae | 318 | |
319 | if (aspath->json) { | |
320 | json_object_free(aspath->json); | |
321 | aspath->json = NULL; | |
322 | } | |
f1aa5d8a | 323 | |
d62a17ae | 324 | XFREE(MTYPE_AS_PATH, aspath); |
718e3744 | 325 | } |
326 | ||
327 | /* Unintern aspath from AS path bucket. */ | |
d62a17ae | 328 | void aspath_unintern(struct aspath **aspath) |
718e3744 | 329 | { |
d62a17ae | 330 | struct aspath *ret; |
331 | struct aspath *asp = *aspath; | |
332 | ||
333 | if (asp->refcnt) | |
334 | asp->refcnt--; | |
718e3744 | 335 | |
d62a17ae | 336 | if (asp->refcnt == 0) { |
337 | /* This aspath must exist in aspath hash table. */ | |
338 | ret = hash_release(ashash, asp); | |
339 | assert(ret != NULL); | |
340 | aspath_free(asp); | |
341 | *aspath = NULL; | |
342 | } | |
718e3744 | 343 | } |
344 | ||
345 | /* Return the start or end delimiters for a particular Segment type */ | |
346 | #define AS_SEG_START 0 | |
347 | #define AS_SEG_END 1 | |
d7c0a89a | 348 | static char aspath_delimiter_char(uint8_t type, uint8_t which) |
d62a17ae | 349 | { |
350 | int i; | |
351 | struct { | |
352 | int type; | |
353 | char start; | |
354 | char end; | |
355 | } aspath_delim_char[] = {{AS_SET, '{', '}'}, | |
356 | {AS_CONFED_SET, '[', ']'}, | |
357 | {AS_CONFED_SEQUENCE, '(', ')'}, | |
358 | {0}}; | |
359 | ||
360 | for (i = 0; aspath_delim_char[i].type != 0; i++) { | |
361 | if (aspath_delim_char[i].type == type) { | |
362 | if (which == AS_SEG_START) | |
363 | return aspath_delim_char[i].start; | |
364 | else if (which == AS_SEG_END) | |
365 | return aspath_delim_char[i].end; | |
366 | } | |
718e3744 | 367 | } |
d62a17ae | 368 | return ' '; |
718e3744 | 369 | } |
370 | ||
014b670e | 371 | /* countup asns from this segment and index onward */ |
d62a17ae | 372 | static int assegment_count_asns(struct assegment *seg, int from) |
373 | { | |
374 | int count = 0; | |
375 | while (seg) { | |
376 | if (!from) | |
377 | count += seg->length; | |
378 | else { | |
379 | count += (seg->length - from); | |
380 | from = 0; | |
381 | } | |
382 | seg = seg->next; | |
383 | } | |
384 | return count; | |
385 | } | |
386 | ||
387 | unsigned int aspath_count_confeds(struct aspath *aspath) | |
388 | { | |
389 | int count = 0; | |
390 | struct assegment *seg = aspath->segments; | |
391 | ||
392 | while (seg) { | |
393 | if (seg->type == AS_CONFED_SEQUENCE) | |
394 | count += seg->length; | |
395 | else if (seg->type == AS_CONFED_SET) | |
396 | count++; | |
397 | ||
398 | seg = seg->next; | |
399 | } | |
400 | return count; | |
401 | } | |
402 | ||
403 | unsigned int aspath_count_hops(const struct aspath *aspath) | |
404 | { | |
405 | int count = 0; | |
406 | struct assegment *seg = aspath->segments; | |
407 | ||
408 | while (seg) { | |
409 | if (seg->type == AS_SEQUENCE) | |
410 | count += seg->length; | |
411 | else if (seg->type == AS_SET) | |
412 | count++; | |
413 | ||
414 | seg = seg->next; | |
415 | } | |
416 | return count; | |
fe69a505 | 417 | } |
418 | ||
0b2aa3a0 PJ |
419 | /* Estimate size aspath /might/ take if encoded into an |
420 | * ASPATH attribute. | |
421 | * | |
422 | * This is a quick estimate, not definitive! aspath_put() | |
423 | * may return a different number!! | |
424 | */ | |
d62a17ae | 425 | unsigned int aspath_size(struct aspath *aspath) |
fe69a505 | 426 | { |
d62a17ae | 427 | int size = 0; |
428 | struct assegment *seg = aspath->segments; | |
429 | ||
430 | while (seg) { | |
431 | size += ASSEGMENT_SIZE(seg->length, 1); | |
432 | seg = seg->next; | |
433 | } | |
434 | return size; | |
fe69a505 | 435 | } |
436 | ||
2815e61f | 437 | /* Return highest public ASN in path */ |
d62a17ae | 438 | as_t aspath_highest(struct aspath *aspath) |
439 | { | |
440 | struct assegment *seg = aspath->segments; | |
441 | as_t highest = 0; | |
442 | unsigned int i; | |
443 | ||
444 | while (seg) { | |
445 | for (i = 0; i < seg->length; i++) | |
446 | if (seg->as[i] > highest | |
447 | && !BGP_AS_IS_PRIVATE(seg->as[i])) | |
448 | highest = seg->as[i]; | |
449 | seg = seg->next; | |
450 | } | |
451 | return highest; | |
2815e61f PJ |
452 | } |
453 | ||
bc3dd427 | 454 | /* Return the left-most ASN in path */ |
d62a17ae | 455 | as_t aspath_leftmost(struct aspath *aspath) |
bc3dd427 | 456 | { |
d62a17ae | 457 | struct assegment *seg = aspath->segments; |
458 | as_t leftmost = 0; | |
bc3dd427 | 459 | |
d62a17ae | 460 | if (seg && seg->length && seg->type == AS_SEQUENCE) |
461 | leftmost = seg->as[0]; | |
bc3dd427 | 462 | |
d62a17ae | 463 | return leftmost; |
bc3dd427 DW |
464 | } |
465 | ||
0b2aa3a0 | 466 | /* Return 1 if there are any 4-byte ASes in the path */ |
d62a17ae | 467 | unsigned int aspath_has_as4(struct aspath *aspath) |
468 | { | |
469 | struct assegment *seg = aspath->segments; | |
470 | unsigned int i; | |
471 | ||
472 | while (seg) { | |
473 | for (i = 0; i < seg->length; i++) | |
474 | if (seg->as[i] > BGP_AS_MAX) | |
475 | return 1; | |
476 | seg = seg->next; | |
477 | } | |
478 | return 0; | |
0b2aa3a0 PJ |
479 | } |
480 | ||
718e3744 | 481 | /* Convert aspath structure to string expression. */ |
68e1a55b | 482 | static void aspath_make_str_count(struct aspath *as, bool make_json) |
d62a17ae | 483 | { |
484 | struct assegment *seg; | |
485 | int str_size; | |
486 | int len = 0; | |
487 | char *str_buf; | |
488 | json_object *jaspath_segments = NULL; | |
489 | json_object *jseg = NULL; | |
490 | json_object *jseg_list = NULL; | |
491 | ||
68e1a55b DS |
492 | if (make_json) { |
493 | as->json = json_object_new_object(); | |
494 | jaspath_segments = json_object_new_array(); | |
495 | } | |
d62a17ae | 496 | |
497 | /* Empty aspath. */ | |
498 | if (!as->segments) { | |
68e1a55b DS |
499 | if (make_json) { |
500 | json_object_string_add(as->json, "string", "Local"); | |
996c9314 LB |
501 | json_object_object_add(as->json, "segments", |
502 | jaspath_segments); | |
68e1a55b DS |
503 | json_object_int_add(as->json, "length", 0); |
504 | } | |
d62a17ae | 505 | as->str = XMALLOC(MTYPE_AS_STR, 1); |
506 | as->str[0] = '\0'; | |
507 | as->str_len = 0; | |
508 | return; | |
509 | } | |
510 | ||
511 | seg = as->segments; | |
512 | ||
513 | /* ASN takes 5 to 10 chars plus seperator, see below. | |
514 | * If there is one differing segment type, we need an additional | |
515 | * 2 chars for segment delimiters, and the final '\0'. | |
516 | * Hopefully this is large enough to avoid hitting the realloc | |
517 | * code below for most common sequences. | |
518 | * | |
519 | * This was changed to 10 after the well-known BGP assertion, which | |
520 | * had hit some parts of the Internet in May of 2009. | |
521 | */ | |
014b670e | 522 | #define ASN_STR_LEN (10 + 1) |
d62a17ae | 523 | str_size = MAX(assegment_count_asns(seg, 0) * ASN_STR_LEN + 2 + 1, |
524 | ASPATH_STR_DEFAULT_LEN); | |
525 | str_buf = XMALLOC(MTYPE_AS_STR, str_size); | |
526 | ||
527 | while (seg) { | |
528 | int i; | |
529 | char seperator; | |
530 | ||
531 | /* Check AS type validity. Set seperator for segment */ | |
532 | switch (seg->type) { | |
533 | case AS_SET: | |
534 | case AS_CONFED_SET: | |
535 | seperator = ','; | |
536 | break; | |
537 | case AS_SEQUENCE: | |
538 | case AS_CONFED_SEQUENCE: | |
539 | seperator = ' '; | |
540 | break; | |
541 | default: | |
542 | XFREE(MTYPE_AS_STR, str_buf); | |
543 | as->str = NULL; | |
544 | as->str_len = 0; | |
545 | json_object_free(as->json); | |
546 | as->json = NULL; | |
68e1a55b | 547 | |
d62a17ae | 548 | return; |
549 | } | |
550 | ||
551 | /* We might need to increase str_buf, particularly if path has | |
552 | * differing segments types, our initial guesstimate above will | |
553 | * have been wrong. Need 10 chars for ASN, a seperator each and | |
554 | * potentially two segment delimiters, plus a space between each | |
555 | * segment and trailing zero. | |
556 | * | |
557 | * This definitely didn't work with the value of 5 bytes and | |
558 | * 32-bit ASNs. | |
559 | */ | |
014b670e | 560 | #define SEGMENT_STR_LEN(X) (((X)->length * ASN_STR_LEN) + 2 + 1 + 1) |
d62a17ae | 561 | if ((len + SEGMENT_STR_LEN(seg)) > str_size) { |
562 | str_size = len + SEGMENT_STR_LEN(seg); | |
563 | str_buf = XREALLOC(MTYPE_AS_STR, str_buf, str_size); | |
564 | } | |
014b670e DO |
565 | #undef ASN_STR_LEN |
566 | #undef SEGMENT_STR_LEN | |
d62a17ae | 567 | |
568 | if (seg->type != AS_SEQUENCE) | |
569 | len += snprintf( | |
570 | str_buf + len, str_size - len, "%c", | |
571 | aspath_delimiter_char(seg->type, AS_SEG_START)); | |
572 | ||
68e1a55b DS |
573 | if (make_json) |
574 | jseg_list = json_object_new_array(); | |
d62a17ae | 575 | |
576 | /* write out the ASNs, with their seperators, bar the last one*/ | |
577 | for (i = 0; i < seg->length; i++) { | |
68e1a55b | 578 | if (make_json) |
996c9314 LB |
579 | json_object_array_add( |
580 | jseg_list, | |
ca9e5ab3 | 581 | json_object_new_int64(seg->as[i])); |
d62a17ae | 582 | |
583 | len += snprintf(str_buf + len, str_size - len, "%u", | |
584 | seg->as[i]); | |
585 | ||
586 | if (i < (seg->length - 1)) | |
587 | len += snprintf(str_buf + len, str_size - len, | |
588 | "%c", seperator); | |
589 | } | |
590 | ||
68e1a55b DS |
591 | if (make_json) { |
592 | jseg = json_object_new_object(); | |
996c9314 LB |
593 | json_object_string_add( |
594 | jseg, "type", | |
595 | aspath_segment_type_str[seg->type]); | |
68e1a55b DS |
596 | json_object_object_add(jseg, "list", jseg_list); |
597 | json_object_array_add(jaspath_segments, jseg); | |
598 | } | |
d62a17ae | 599 | |
600 | if (seg->type != AS_SEQUENCE) | |
601 | len += snprintf( | |
602 | str_buf + len, str_size - len, "%c", | |
603 | aspath_delimiter_char(seg->type, AS_SEG_END)); | |
604 | if (seg->next) | |
605 | len += snprintf(str_buf + len, str_size - len, " "); | |
606 | ||
607 | seg = seg->next; | |
608 | } | |
609 | ||
610 | assert(len < str_size); | |
611 | ||
612 | str_buf[len] = '\0'; | |
613 | as->str = str_buf; | |
614 | as->str_len = len; | |
615 | ||
68e1a55b DS |
616 | if (make_json) { |
617 | json_object_string_add(as->json, "string", str_buf); | |
618 | json_object_object_add(as->json, "segments", jaspath_segments); | |
619 | json_object_int_add(as->json, "length", aspath_count_hops(as)); | |
620 | } | |
621 | ||
d62a17ae | 622 | return; |
623 | } | |
624 | ||
68e1a55b | 625 | void aspath_str_update(struct aspath *as, bool make_json) |
d62a17ae | 626 | { |
0a22ddfb | 627 | XFREE(MTYPE_AS_STR, as->str); |
d62a17ae | 628 | |
629 | if (as->json) { | |
630 | json_object_free(as->json); | |
631 | as->json = NULL; | |
632 | } | |
633 | ||
68e1a55b | 634 | aspath_make_str_count(as, make_json); |
fe69a505 | 635 | } |
636 | ||
718e3744 | 637 | /* Intern allocated AS path. */ |
d62a17ae | 638 | struct aspath *aspath_intern(struct aspath *aspath) |
718e3744 | 639 | { |
d62a17ae | 640 | struct aspath *find; |
f669f7d2 | 641 | |
d62a17ae | 642 | /* Assert this AS path structure is not interned and has the string |
643 | representation built. */ | |
644 | assert(aspath->refcnt == 0); | |
645 | assert(aspath->str); | |
718e3744 | 646 | |
d62a17ae | 647 | /* Check AS path hash. */ |
648 | find = hash_get(ashash, aspath, hash_alloc_intern); | |
649 | if (find != aspath) | |
650 | aspath_free(aspath); | |
718e3744 | 651 | |
d62a17ae | 652 | find->refcnt++; |
718e3744 | 653 | |
d62a17ae | 654 | return find; |
718e3744 | 655 | } |
656 | ||
657 | /* Duplicate aspath structure. Created same aspath structure but | |
658 | reference count and AS path string is cleared. */ | |
d62a17ae | 659 | struct aspath *aspath_dup(struct aspath *aspath) |
718e3744 | 660 | { |
d62a17ae | 661 | unsigned short buflen = aspath->str_len + 1; |
662 | struct aspath *new; | |
718e3744 | 663 | |
d62a17ae | 664 | new = XCALLOC(MTYPE_AS_PATH, sizeof(struct aspath)); |
665 | new->json = NULL; | |
718e3744 | 666 | |
d62a17ae | 667 | if (aspath->segments) |
668 | new->segments = assegment_dup_all(aspath->segments); | |
718e3744 | 669 | |
d62a17ae | 670 | if (!aspath->str) |
671 | return new; | |
f669f7d2 | 672 | |
d62a17ae | 673 | new->str = XMALLOC(MTYPE_AS_STR, buflen); |
674 | new->str_len = aspath->str_len; | |
f669f7d2 | 675 | |
d62a17ae | 676 | /* copy the string data */ |
677 | if (aspath->str_len > 0) | |
678 | memcpy(new->str, aspath->str, buflen); | |
679 | else | |
680 | new->str[0] = '\0'; | |
718e3744 | 681 | |
d62a17ae | 682 | return new; |
718e3744 | 683 | } |
684 | ||
d62a17ae | 685 | static void *aspath_hash_alloc(void *arg) |
718e3744 | 686 | { |
d62a17ae | 687 | const struct aspath *aspath = arg; |
688 | struct aspath *new; | |
718e3744 | 689 | |
d62a17ae | 690 | /* Malformed AS path value. */ |
691 | assert(aspath->str); | |
718e3744 | 692 | |
d62a17ae | 693 | /* New aspath structure is needed. */ |
694 | new = XMALLOC(MTYPE_AS_PATH, sizeof(struct aspath)); | |
f669f7d2 | 695 | |
d62a17ae | 696 | /* Reuse segments and string representation */ |
697 | new->refcnt = 0; | |
698 | new->segments = aspath->segments; | |
699 | new->str = aspath->str; | |
700 | new->str_len = aspath->str_len; | |
701 | new->json = aspath->json; | |
f669f7d2 | 702 | |
d62a17ae | 703 | return new; |
718e3744 | 704 | } |
705 | ||
ab005298 | 706 | /* parse as-segment byte stream in struct assegment */ |
d62a17ae | 707 | static int assegments_parse(struct stream *s, size_t length, |
708 | struct assegment **result, int use32bit) | |
709 | { | |
710 | struct assegment_header segh; | |
711 | struct assegment *seg, *prev = NULL, *head = NULL; | |
712 | size_t bytes = 0; | |
713 | ||
714 | /* empty aspath (ie iBGP or somesuch) */ | |
715 | if (length == 0) | |
716 | return 0; | |
717 | ||
718 | if (BGP_DEBUG(as4, AS4_SEGMENT)) | |
719 | zlog_debug( | |
720 | "[AS4SEG] Parse aspath segment: got total byte length %lu", | |
721 | (unsigned long)length); | |
722 | /* basic checks */ | |
723 | if ((STREAM_READABLE(s) < length) | |
724 | || (STREAM_READABLE(s) < AS_HEADER_SIZE) | |
725 | || (length % AS16_VALUE_SIZE)) | |
726 | return -1; | |
727 | ||
728 | while (bytes < length) { | |
729 | int i; | |
730 | size_t seg_size; | |
731 | ||
732 | if ((length - bytes) <= AS_HEADER_SIZE) { | |
733 | if (head) | |
734 | assegment_free_all(head); | |
735 | return -1; | |
736 | } | |
737 | ||
738 | /* softly softly, get the header first on its own */ | |
739 | segh.type = stream_getc(s); | |
740 | segh.length = stream_getc(s); | |
741 | ||
742 | seg_size = ASSEGMENT_SIZE(segh.length, use32bit); | |
743 | ||
744 | if (BGP_DEBUG(as4, AS4_SEGMENT)) | |
745 | zlog_debug( | |
746 | "[AS4SEG] Parse aspath segment: got type %d, length %d", | |
747 | segh.type, segh.length); | |
748 | ||
749 | /* check it.. */ | |
750 | if (((bytes + seg_size) > length) | |
751 | /* 1771bis 4.3b: seg length contains one or more */ | |
752 | || (segh.length == 0) | |
753 | /* Paranoia in case someone changes type of segment length. | |
754 | * Shift both values by 0x10 to make the comparison operate | |
755 | * on more, than 8 bits (otherwise it's a warning, bug | |
756 | * #564). | |
757 | */ | |
758 | || ((sizeof segh.length > 1) | |
759 | && (0x10 + segh.length > 0x10 + AS_SEGMENT_MAX))) { | |
760 | if (head) | |
761 | assegment_free_all(head); | |
762 | return -1; | |
763 | } | |
764 | ||
765 | switch (segh.type) { | |
766 | case AS_SEQUENCE: | |
767 | case AS_SET: | |
768 | case AS_CONFED_SEQUENCE: | |
769 | case AS_CONFED_SET: | |
770 | break; | |
771 | default: | |
772 | if (head) | |
773 | assegment_free_all(head); | |
774 | return -1; | |
775 | } | |
776 | ||
777 | /* now its safe to trust lengths */ | |
778 | seg = assegment_new(segh.type, segh.length); | |
779 | ||
780 | if (head) | |
781 | prev->next = seg; | |
782 | else /* it's the first segment */ | |
783 | head = prev = seg; | |
784 | ||
785 | for (i = 0; i < segh.length; i++) | |
786 | seg->as[i] = | |
787 | (use32bit) ? stream_getl(s) : stream_getw(s); | |
788 | ||
789 | bytes += seg_size; | |
790 | ||
791 | if (BGP_DEBUG(as4, AS4_SEGMENT)) | |
792 | zlog_debug( | |
793 | "[AS4SEG] Parse aspath segment: Bytes now: %lu", | |
794 | (unsigned long)bytes); | |
795 | ||
796 | prev = seg; | |
797 | } | |
798 | ||
799 | *result = assegment_normalise(head); | |
800 | return 0; | |
fe69a505 | 801 | } |
802 | ||
ab005298 PJ |
803 | /* AS path parse function. pnt is a pointer to byte stream and length |
804 | is length of byte stream. If there is same AS path in the the AS | |
d62a17ae | 805 | path hash then return it else make new AS path structure. |
806 | ||
b881c707 | 807 | On error NULL is returned. |
cddb8112 | 808 | */ |
d62a17ae | 809 | struct aspath *aspath_parse(struct stream *s, size_t length, int use32bit) |
810 | { | |
811 | struct aspath as; | |
812 | struct aspath *find; | |
813 | ||
814 | /* If length is odd it's malformed AS path. */ | |
815 | /* Nit-picking: if (use32bit == 0) it is malformed if odd, | |
816 | * otherwise its malformed when length is larger than 2 and (length-2) | |
817 | * is not dividable by 4. | |
818 | * But... this time we're lazy | |
819 | */ | |
820 | if (length % AS16_VALUE_SIZE) | |
821 | return NULL; | |
822 | ||
823 | memset(&as, 0, sizeof(struct aspath)); | |
824 | if (assegments_parse(s, length, &as.segments, use32bit) < 0) | |
825 | return NULL; | |
826 | ||
827 | /* If already same aspath exist then return it. */ | |
828 | find = hash_get(ashash, &as, aspath_hash_alloc); | |
829 | ||
830 | /* bug! should not happen, let the daemon crash below */ | |
831 | assert(find); | |
832 | ||
833 | /* if the aspath was already hashed free temporary memory. */ | |
834 | if (find->refcnt) { | |
835 | assegment_free_all(as.segments); | |
836 | /* aspath_key_make() always updates the string */ | |
837 | XFREE(MTYPE_AS_STR, as.str); | |
838 | if (as.json) { | |
839 | json_object_free(as.json); | |
840 | as.json = NULL; | |
841 | } | |
4390a8ee | 842 | } |
f669f7d2 | 843 | |
d62a17ae | 844 | find->refcnt++; |
718e3744 | 845 | |
d62a17ae | 846 | return find; |
718e3744 | 847 | } |
848 | ||
d62a17ae | 849 | static void assegment_data_put(struct stream *s, as_t *as, int num, |
850 | int use32bit) | |
fe69a505 | 851 | { |
d62a17ae | 852 | int i; |
853 | assert(num <= AS_SEGMENT_MAX); | |
854 | ||
855 | for (i = 0; i < num; i++) | |
856 | if (use32bit) | |
857 | stream_putl(s, as[i]); | |
858 | else { | |
859 | if (as[i] <= BGP_AS_MAX) | |
860 | stream_putw(s, as[i]); | |
861 | else | |
862 | stream_putw(s, BGP_AS_TRANS); | |
863 | } | |
fe69a505 | 864 | } |
718e3744 | 865 | |
d7c0a89a | 866 | static size_t assegment_header_put(struct stream *s, uint8_t type, int length) |
718e3744 | 867 | { |
d62a17ae | 868 | size_t lenp; |
869 | assert(length <= AS_SEGMENT_MAX); | |
870 | stream_putc(s, type); | |
871 | lenp = stream_get_endp(s); | |
872 | stream_putc(s, length); | |
873 | return lenp; | |
fe69a505 | 874 | } |
718e3744 | 875 | |
fe69a505 | 876 | /* write aspath data to stream */ |
d62a17ae | 877 | size_t aspath_put(struct stream *s, struct aspath *as, int use32bit) |
878 | { | |
879 | struct assegment *seg = as->segments; | |
880 | size_t bytes = 0; | |
881 | ||
882 | if (!seg || seg->length == 0) | |
883 | return 0; | |
884 | ||
885 | if (seg) { | |
886 | /* | |
887 | * Hey, what do we do when we have > STREAM_WRITABLE(s) here? | |
888 | * At the moment, we would write out a partial aspath, and our | |
889 | * peer | |
890 | * will complain and drop the session :-/ | |
891 | * | |
892 | * The general assumption here is that many things tested will | |
893 | * never happen. And, in real live, up to now, they have not. | |
894 | */ | |
9d303b37 DL |
895 | while (seg && (ASSEGMENT_LEN(seg, use32bit) |
896 | <= STREAM_WRITEABLE(s))) { | |
d62a17ae | 897 | struct assegment *next = seg->next; |
898 | int written = 0; | |
899 | int asns_packed = 0; | |
900 | size_t lenp; | |
901 | ||
902 | /* Overlength segments have to be split up */ | |
903 | while ((seg->length - written) > AS_SEGMENT_MAX) { | |
904 | assegment_header_put(s, seg->type, | |
905 | AS_SEGMENT_MAX); | |
248c86da | 906 | assegment_data_put(s, (seg->as + written), AS_SEGMENT_MAX, |
d62a17ae | 907 | use32bit); |
908 | written += AS_SEGMENT_MAX; | |
996c9314 LB |
909 | bytes += ASSEGMENT_SIZE(AS_SEGMENT_MAX, |
910 | use32bit); | |
d62a17ae | 911 | } |
912 | ||
913 | /* write the final segment, probably is also the first | |
914 | */ | |
915 | lenp = assegment_header_put(s, seg->type, | |
916 | seg->length - written); | |
917 | assegment_data_put(s, (seg->as + written), | |
918 | seg->length - written, use32bit); | |
919 | ||
920 | /* Sequence-type segments can be 'packed' together | |
921 | * Case of a segment which was overlength and split up | |
922 | * will be missed here, but that doesn't matter. | |
923 | */ | |
924 | while (next && ASSEGMENTS_PACKABLE(seg, next)) { | |
925 | /* NB: We should never normally get here given | |
926 | * we | |
927 | * normalise aspath data when parse them. | |
928 | * However, better | |
929 | * safe than sorry. We potentially could call | |
930 | * assegment_normalise here instead, but it's | |
931 | * cheaper and | |
932 | * easier to do it on the fly here rather than | |
933 | * go through | |
934 | * the segment list twice every time we write | |
935 | * out | |
936 | * aspath's. | |
937 | */ | |
938 | ||
939 | /* Next segment's data can fit in this one */ | |
940 | assegment_data_put(s, next->as, next->length, | |
941 | use32bit); | |
942 | ||
943 | /* update the length of the segment header */ | |
944 | stream_putc_at(s, lenp, | |
945 | seg->length - written | |
946 | + next->length); | |
947 | asns_packed += next->length; | |
948 | ||
949 | next = next->next; | |
950 | } | |
951 | ||
952 | bytes += ASSEGMENT_SIZE( | |
953 | seg->length - written + asns_packed, use32bit); | |
954 | seg = next; | |
955 | } | |
956 | } | |
957 | return bytes; | |
fe69a505 | 958 | } |
959 | ||
960 | /* This is for SNMP BGP4PATHATTRASPATHSEGMENT | |
961 | * We have no way to manage the storage, so we use a static stream | |
962 | * wrapper around aspath_put. | |
963 | */ | |
d7c0a89a | 964 | uint8_t *aspath_snmp_pathseg(struct aspath *as, size_t *varlen) |
fe69a505 | 965 | { |
966 | #define SNMP_PATHSEG_MAX 1024 | |
8fdc32ab | 967 | |
d62a17ae | 968 | if (!snmp_stream) |
969 | snmp_stream = stream_new(SNMP_PATHSEG_MAX); | |
970 | else | |
971 | stream_reset(snmp_stream); | |
972 | ||
973 | if (!as) { | |
974 | *varlen = 0; | |
975 | return NULL; | |
976 | } | |
977 | aspath_put(snmp_stream, as, 0); /* use 16 bit for now here */ | |
978 | ||
979 | *varlen = stream_get_endp(snmp_stream); | |
980 | return stream_pnt(snmp_stream); | |
981 | } | |
982 | ||
fe69a505 | 983 | #define min(A,B) ((A) < (B) ? (A) : (B)) |
718e3744 | 984 | |
d62a17ae | 985 | static struct assegment *aspath_aggregate_as_set_add(struct aspath *aspath, |
986 | struct assegment *asset, | |
987 | as_t as) | |
988 | { | |
989 | int i; | |
990 | ||
991 | /* If this is first AS set member, create new as-set segment. */ | |
992 | if (asset == NULL) { | |
993 | asset = assegment_new(AS_SET, 1); | |
994 | if (!aspath->segments) | |
995 | aspath->segments = asset; | |
996 | else { | |
997 | struct assegment *seg = aspath->segments; | |
998 | while (seg->next) | |
999 | seg = seg->next; | |
1000 | seg->next = asset; | |
1001 | } | |
1002 | asset->type = AS_SET; | |
1003 | asset->length = 1; | |
1004 | asset->as[0] = as; | |
1005 | } else { | |
1006 | /* Check this AS value already exists or not. */ | |
1007 | for (i = 0; i < asset->length; i++) | |
1008 | if (asset->as[i] == as) | |
1009 | return asset; | |
1010 | ||
1011 | asset->length++; | |
1012 | asset->as = XREALLOC(MTYPE_AS_SEG_DATA, asset->as, | |
1013 | asset->length * AS_VALUE_SIZE); | |
1014 | asset->as[asset->length - 1] = as; | |
1015 | } | |
1016 | ||
1017 | ||
1018 | return asset; | |
718e3744 | 1019 | } |
1020 | ||
1021 | /* Modify as1 using as2 for aggregation. */ | |
d62a17ae | 1022 | struct aspath *aspath_aggregate(struct aspath *as1, struct aspath *as2) |
1023 | { | |
1024 | int i; | |
1025 | int minlen = 0; | |
1026 | int match = 0; | |
1027 | int from; | |
1028 | struct assegment *seg1 = as1->segments; | |
1029 | struct assegment *seg2 = as2->segments; | |
1030 | struct aspath *aspath = NULL; | |
1031 | struct assegment *asset = NULL; | |
1032 | struct assegment *prevseg = NULL; | |
1033 | ||
1034 | /* First of all check common leading sequence. */ | |
1035 | while (seg1 && seg2) { | |
1036 | /* Check segment type. */ | |
1037 | if (seg1->type != seg2->type) | |
1038 | break; | |
1039 | ||
1040 | /* Minimum segment length. */ | |
1041 | minlen = min(seg1->length, seg2->length); | |
1042 | ||
1043 | for (match = 0; match < minlen; match++) | |
1044 | if (seg1->as[match] != seg2->as[match]) | |
1045 | break; | |
1046 | ||
1047 | if (match) { | |
1048 | struct assegment *seg = assegment_new(seg1->type, 0); | |
1049 | ||
1050 | seg = assegment_append_asns(seg, seg1->as, match); | |
1051 | ||
1052 | if (!aspath) { | |
1053 | aspath = aspath_new(); | |
1054 | aspath->segments = seg; | |
1055 | } else | |
1056 | prevseg->next = seg; | |
1057 | ||
1058 | prevseg = seg; | |
1059 | } | |
1060 | ||
1061 | if (match != minlen || match != seg1->length | |
1062 | || seg1->length != seg2->length) | |
1063 | break; | |
1064 | /* We are moving on to the next segment to reset match */ | |
1065 | else | |
1066 | match = 0; | |
1067 | ||
1068 | seg1 = seg1->next; | |
1069 | seg2 = seg2->next; | |
1070 | } | |
1071 | ||
1072 | if (!aspath) | |
1073 | aspath = aspath_new(); | |
1074 | ||
1075 | /* Make as-set using rest of all information. */ | |
1076 | from = match; | |
1077 | while (seg1) { | |
1078 | for (i = from; i < seg1->length; i++) | |
1079 | asset = aspath_aggregate_as_set_add(aspath, asset, | |
1080 | seg1->as[i]); | |
1081 | ||
1082 | from = 0; | |
1083 | seg1 = seg1->next; | |
718e3744 | 1084 | } |
1085 | ||
d62a17ae | 1086 | from = match; |
1087 | while (seg2) { | |
1088 | for (i = from; i < seg2->length; i++) | |
1089 | asset = aspath_aggregate_as_set_add(aspath, asset, | |
1090 | seg2->as[i]); | |
1091 | ||
1092 | from = 0; | |
1093 | seg2 = seg2->next; | |
1094 | } | |
1095 | ||
1096 | assegment_normalise(aspath->segments); | |
68e1a55b | 1097 | aspath_str_update(aspath, false); |
d62a17ae | 1098 | return aspath; |
718e3744 | 1099 | } |
1100 | ||
1101 | /* When a BGP router receives an UPDATE with an MP_REACH_NLRI | |
1102 | attribute, check the leftmost AS number in the AS_PATH attribute is | |
d62a17ae | 1103 | or not the peer's AS number. */ |
1104 | int aspath_firstas_check(struct aspath *aspath, as_t asno) | |
718e3744 | 1105 | { |
d62a17ae | 1106 | if ((aspath == NULL) || (aspath->segments == NULL)) |
1107 | return 0; | |
1108 | ||
1109 | if (aspath->segments && (aspath->segments->type == AS_SEQUENCE) | |
1110 | && (aspath->segments->as[0] == asno)) | |
1111 | return 1; | |
718e3744 | 1112 | |
d62a17ae | 1113 | return 0; |
718e3744 | 1114 | } |
1115 | ||
d62a17ae | 1116 | unsigned int aspath_get_first_as(struct aspath *aspath) |
06370dac | 1117 | { |
d62a17ae | 1118 | if (aspath == NULL || aspath->segments == NULL) |
1119 | return 0; | |
06370dac | 1120 | |
d62a17ae | 1121 | return aspath->segments->as[0]; |
06370dac DW |
1122 | } |
1123 | ||
d62a17ae | 1124 | unsigned int aspath_get_last_as(struct aspath *aspath) |
aac9ef6c | 1125 | { |
d62a17ae | 1126 | int i; |
1127 | unsigned int last_as = 0; | |
1128 | const struct assegment *seg; | |
aac9ef6c | 1129 | |
d62a17ae | 1130 | if (aspath == NULL || aspath->segments == NULL) |
1131 | return last_as; | |
aac9ef6c | 1132 | |
d62a17ae | 1133 | seg = aspath->segments; |
aac9ef6c | 1134 | |
d62a17ae | 1135 | while (seg) { |
1136 | if (seg->type == AS_SEQUENCE || seg->type == AS_CONFED_SEQUENCE) | |
1137 | for (i = 0; i < seg->length; i++) | |
1138 | last_as = seg->as[i]; | |
1139 | seg = seg->next; | |
1140 | } | |
aac9ef6c | 1141 | |
d62a17ae | 1142 | return last_as; |
aac9ef6c DW |
1143 | } |
1144 | ||
1f742f21 | 1145 | /* AS path loop check. If aspath contains asno then return >= 1. */ |
d62a17ae | 1146 | int aspath_loop_check(struct aspath *aspath, as_t asno) |
1147 | { | |
1148 | struct assegment *seg; | |
1149 | int count = 0; | |
1150 | ||
1151 | if ((aspath == NULL) || (aspath->segments == NULL)) | |
1152 | return 0; | |
1153 | ||
1154 | seg = aspath->segments; | |
1155 | ||
1156 | while (seg) { | |
1157 | int i; | |
1158 | ||
1159 | for (i = 0; i < seg->length; i++) | |
1160 | if (seg->as[i] == asno) | |
1161 | count++; | |
1162 | ||
1163 | seg = seg->next; | |
1164 | } | |
1165 | return count; | |
718e3744 | 1166 | } |
1167 | ||
1168 | /* When all of AS path is private AS return 1. */ | |
d62a17ae | 1169 | int aspath_private_as_check(struct aspath *aspath) |
718e3744 | 1170 | { |
d62a17ae | 1171 | struct assegment *seg; |
5000f21c | 1172 | |
d62a17ae | 1173 | if (!(aspath && aspath->segments)) |
1174 | return 0; | |
5000f21c | 1175 | |
d62a17ae | 1176 | seg = aspath->segments; |
718e3744 | 1177 | |
d62a17ae | 1178 | while (seg) { |
1179 | int i; | |
5000f21c | 1180 | |
d62a17ae | 1181 | for (i = 0; i < seg->length; i++) { |
1182 | if (!BGP_AS_IS_PRIVATE(seg->as[i])) | |
1183 | return 0; | |
1184 | } | |
1185 | seg = seg->next; | |
718e3744 | 1186 | } |
d62a17ae | 1187 | return 1; |
718e3744 | 1188 | } |
1189 | ||
c7122e14 | 1190 | /* Return True if the entire ASPATH consist of the specified ASN */ |
d62a17ae | 1191 | int aspath_single_asn_check(struct aspath *aspath, as_t asn) |
c7122e14 | 1192 | { |
d62a17ae | 1193 | struct assegment *seg; |
c7122e14 | 1194 | |
d62a17ae | 1195 | if (!(aspath && aspath->segments)) |
1196 | return 0; | |
c7122e14 | 1197 | |
d62a17ae | 1198 | seg = aspath->segments; |
c7122e14 | 1199 | |
d62a17ae | 1200 | while (seg) { |
1201 | int i; | |
c7122e14 | 1202 | |
d62a17ae | 1203 | for (i = 0; i < seg->length; i++) { |
1204 | if (seg->as[i] != asn) | |
1205 | return 0; | |
1206 | } | |
1207 | seg = seg->next; | |
c7122e14 | 1208 | } |
d62a17ae | 1209 | return 1; |
c7122e14 DS |
1210 | } |
1211 | ||
1212 | /* Replace all instances of the target ASN with our own ASN */ | |
d62a17ae | 1213 | struct aspath *aspath_replace_specific_asn(struct aspath *aspath, |
1214 | as_t target_asn, as_t our_asn) | |
c7122e14 | 1215 | { |
d62a17ae | 1216 | struct aspath *new; |
1217 | struct assegment *seg; | |
c7122e14 | 1218 | |
d62a17ae | 1219 | new = aspath_dup(aspath); |
1220 | seg = new->segments; | |
c7122e14 | 1221 | |
d62a17ae | 1222 | while (seg) { |
1223 | int i; | |
c7122e14 | 1224 | |
d62a17ae | 1225 | for (i = 0; i < seg->length; i++) { |
1226 | if (seg->as[i] == target_asn) | |
1227 | seg->as[i] = our_asn; | |
1228 | } | |
1229 | seg = seg->next; | |
c7122e14 | 1230 | } |
c7122e14 | 1231 | |
68e1a55b | 1232 | aspath_str_update(new, false); |
d62a17ae | 1233 | return new; |
c7122e14 DS |
1234 | } |
1235 | ||
5000f21c | 1236 | /* Replace all private ASNs with our own ASN */ |
bf26b80e DS |
1237 | struct aspath *aspath_replace_private_asns(struct aspath *aspath, as_t asn, |
1238 | as_t peer_asn) | |
5000f21c | 1239 | { |
d62a17ae | 1240 | struct aspath *new; |
1241 | struct assegment *seg; | |
5000f21c | 1242 | |
d62a17ae | 1243 | new = aspath_dup(aspath); |
1244 | seg = new->segments; | |
5000f21c | 1245 | |
d62a17ae | 1246 | while (seg) { |
1247 | int i; | |
5000f21c | 1248 | |
d62a17ae | 1249 | for (i = 0; i < seg->length; i++) { |
bf26b80e DS |
1250 | /* Don't replace if public ASN or peer's ASN */ |
1251 | if (BGP_AS_IS_PRIVATE(seg->as[i]) | |
1252 | && (seg->as[i] != peer_asn)) | |
d62a17ae | 1253 | seg->as[i] = asn; |
1254 | } | |
1255 | seg = seg->next; | |
5000f21c | 1256 | } |
5000f21c | 1257 | |
68e1a55b | 1258 | aspath_str_update(new, false); |
d62a17ae | 1259 | return new; |
5000f21c DS |
1260 | } |
1261 | ||
1262 | /* Remove all private ASNs */ | |
bf26b80e | 1263 | struct aspath *aspath_remove_private_asns(struct aspath *aspath, as_t peer_asn) |
d62a17ae | 1264 | { |
1265 | struct aspath *new; | |
1266 | struct assegment *seg; | |
1267 | struct assegment *new_seg; | |
1268 | struct assegment *last_new_seg; | |
1269 | int i; | |
1270 | int j; | |
1271 | int public = 0; | |
1272 | ||
1273 | new = XCALLOC(MTYPE_AS_PATH, sizeof(struct aspath)); | |
1274 | ||
1275 | new->json = NULL; | |
1276 | new_seg = NULL; | |
1277 | last_new_seg = NULL; | |
1278 | seg = aspath->segments; | |
1279 | while (seg) { | |
1280 | public | |
1281 | = 0; | |
1282 | for (i = 0; i < seg->length; i++) { | |
1283 | // ASN is public | |
1284 | if (!BGP_AS_IS_PRIVATE(seg->as[i])) { | |
1285 | public | |
1286 | ++; | |
1287 | } | |
1288 | } | |
1289 | ||
d62a17ae | 1290 | // The entire segment is public so copy it |
bf26b80e | 1291 | if (public == seg->length) |
d62a17ae | 1292 | new_seg = assegment_dup(seg); |
d62a17ae | 1293 | |
1294 | // The segment is a mix of public and private ASNs. Copy as many | |
1295 | // spots as | |
1296 | // there are public ASNs then come back and fill in only the | |
1297 | // public ASNs. | |
1298 | else { | |
1299 | new_seg = assegment_new(seg->type, public); | |
1300 | j = 0; | |
1301 | for (i = 0; i < seg->length; i++) { | |
bf26b80e DS |
1302 | // keep ASN if public or matches peer's ASN |
1303 | if (!BGP_AS_IS_PRIVATE(seg->as[i]) | |
1304 | || (seg->as[i] == peer_asn)) { | |
d62a17ae | 1305 | new_seg->as[j] = seg->as[i]; |
1306 | j++; | |
1307 | } | |
1308 | } | |
1309 | } | |
1310 | ||
1311 | // This is the first segment so set the aspath segments pointer | |
1312 | // to this one | |
1313 | if (!last_new_seg) | |
1314 | new->segments = new_seg; | |
1315 | else | |
1316 | last_new_seg->next = new_seg; | |
1317 | ||
1318 | last_new_seg = new_seg; | |
1319 | seg = seg->next; | |
1320 | } | |
1321 | ||
68e1a55b | 1322 | aspath_str_update(new, false); |
d62a17ae | 1323 | return new; |
1324 | } | |
1325 | ||
1326 | /* AS path confed check. If aspath contains confed set or sequence then return | |
1327 | * 1. */ | |
1328 | int aspath_confed_check(struct aspath *aspath) | |
1329 | { | |
1330 | struct assegment *seg; | |
1331 | ||
1332 | if (!(aspath && aspath->segments)) | |
1333 | return 0; | |
1334 | ||
1335 | seg = aspath->segments; | |
1336 | ||
1337 | while (seg) { | |
1338 | if (seg->type == AS_CONFED_SET | |
1339 | || seg->type == AS_CONFED_SEQUENCE) | |
1340 | return 1; | |
1341 | seg = seg->next; | |
1342 | } | |
1343 | return 0; | |
ca87e1d3 VT |
1344 | } |
1345 | ||
1346 | /* Leftmost AS path segment confed check. If leftmost AS segment is of type | |
1347 | AS_CONFED_SEQUENCE or AS_CONFED_SET then return 1. */ | |
d62a17ae | 1348 | int aspath_left_confed_check(struct aspath *aspath) |
ca87e1d3 VT |
1349 | { |
1350 | ||
d62a17ae | 1351 | if (!(aspath && aspath->segments)) |
1352 | return 0; | |
ca87e1d3 | 1353 | |
d62a17ae | 1354 | if ((aspath->segments->type == AS_CONFED_SEQUENCE) |
1355 | || (aspath->segments->type == AS_CONFED_SET)) | |
1356 | return 1; | |
ca87e1d3 | 1357 | |
d62a17ae | 1358 | return 0; |
ca87e1d3 VT |
1359 | } |
1360 | ||
718e3744 | 1361 | /* Merge as1 to as2. as2 should be uninterned aspath. */ |
d62a17ae | 1362 | static struct aspath *aspath_merge(struct aspath *as1, struct aspath *as2) |
718e3744 | 1363 | { |
d62a17ae | 1364 | struct assegment *last, *new; |
718e3744 | 1365 | |
d62a17ae | 1366 | if (!as1 || !as2) |
1367 | return NULL; | |
718e3744 | 1368 | |
d62a17ae | 1369 | last = new = assegment_dup_all(as1->segments); |
1370 | ||
1371 | /* find the last valid segment */ | |
1372 | while (last && last->next) | |
1373 | last = last->next; | |
1374 | ||
e00d8008 NT |
1375 | if (last) |
1376 | last->next = as2->segments; | |
d62a17ae | 1377 | as2->segments = new; |
68e1a55b | 1378 | aspath_str_update(as2, false); |
d62a17ae | 1379 | return as2; |
718e3744 | 1380 | } |
1381 | ||
1382 | /* Prepend as1 to as2. as2 should be uninterned aspath. */ | |
d62a17ae | 1383 | struct aspath *aspath_prepend(struct aspath *as1, struct aspath *as2) |
1384 | { | |
3c510881 QY |
1385 | struct assegment *as1segtail; |
1386 | struct assegment *as2segtail; | |
1387 | struct assegment *as2seghead; | |
d62a17ae | 1388 | |
1389 | if (!as1 || !as2) | |
1390 | return NULL; | |
1391 | ||
d62a17ae | 1392 | /* If as2 is empty, only need to dupe as1's chain onto as2 */ |
3c510881 | 1393 | if (as2->segments == NULL) { |
d62a17ae | 1394 | as2->segments = assegment_dup_all(as1->segments); |
68e1a55b | 1395 | aspath_str_update(as2, false); |
d62a17ae | 1396 | return as2; |
1397 | } | |
1398 | ||
1399 | /* If as1 is empty AS, no prepending to do. */ | |
3c510881 | 1400 | if (as1->segments == NULL) |
d62a17ae | 1401 | return as2; |
1402 | ||
1403 | /* find the tail as1's segment chain. */ | |
3c510881 QY |
1404 | as1segtail = as1->segments; |
1405 | while (as1segtail && as1segtail->next) | |
1406 | as1segtail = as1segtail->next; | |
d62a17ae | 1407 | |
1408 | /* Delete any AS_CONFED_SEQUENCE segment from as2. */ | |
3c510881 QY |
1409 | if (as1segtail->type == AS_SEQUENCE |
1410 | && as2->segments->type == AS_CONFED_SEQUENCE) | |
d62a17ae | 1411 | as2 = aspath_delete_confed_seq(as2); |
1412 | ||
3c510881 QY |
1413 | if (!as2->segments) { |
1414 | as2->segments = assegment_dup_all(as1->segments); | |
1415 | aspath_str_update(as2, false); | |
1416 | return as2; | |
1417 | } | |
1418 | ||
d62a17ae | 1419 | /* Compare last segment type of as1 and first segment type of as2. */ |
3c510881 | 1420 | if (as1segtail->type != as2->segments->type) |
d62a17ae | 1421 | return aspath_merge(as1, as2); |
1422 | ||
3c510881 | 1423 | if (as1segtail->type == AS_SEQUENCE) { |
d62a17ae | 1424 | /* We have two chains of segments, as1->segments and seg2, |
1425 | * and we have to attach them together, merging the attaching | |
1426 | * segments together into one. | |
1427 | * | |
1428 | * 1. dupe as1->segments onto head of as2 | |
1429 | * 2. merge seg2's asns onto last segment of this new chain | |
1430 | * 3. attach chain after seg2 | |
1431 | */ | |
1432 | ||
3c510881 QY |
1433 | /* save as2 head */ |
1434 | as2seghead = as2->segments; | |
1435 | ||
d62a17ae | 1436 | /* dupe as1 onto as2's head */ |
3c510881 | 1437 | as2segtail = as2->segments = assegment_dup_all(as1->segments); |
d62a17ae | 1438 | |
3c510881 QY |
1439 | /* refind the tail of as2 */ |
1440 | while (as2segtail && as2segtail->next) | |
1441 | as2segtail = as2segtail->next; | |
d62a17ae | 1442 | |
1443 | /* merge the old head, seg2, into tail, seg1 */ | |
3c510881 QY |
1444 | assegment_append_asns(as2segtail, as2seghead->as, |
1445 | as2seghead->length); | |
d62a17ae | 1446 | |
3c510881 QY |
1447 | /* |
1448 | * bypass the merged seg2, and attach any chain after it | |
1449 | * to chain descending from as2's head | |
d62a17ae | 1450 | */ |
e00d8008 NT |
1451 | if (as2segtail) |
1452 | as2segtail->next = as2seghead->next; | |
d62a17ae | 1453 | |
3c510881 QY |
1454 | /* as2->segments is now referenceless and useless */ |
1455 | assegment_free(as2seghead); | |
d62a17ae | 1456 | |
1457 | /* we've now prepended as1's segment chain to as2, merging | |
1458 | * the inbetween AS_SEQUENCE of seg2 in the process | |
1459 | */ | |
68e1a55b | 1460 | aspath_str_update(as2, false); |
d62a17ae | 1461 | return as2; |
1462 | } else { | |
1463 | /* AS_SET merge code is needed at here. */ | |
1464 | return aspath_merge(as1, as2); | |
1465 | } | |
1466 | /* XXX: Ermmm, what if as1 has multiple segments?? */ | |
1467 | ||
1468 | /* Not reached */ | |
718e3744 | 1469 | } |
1470 | ||
f79f7a7b | 1471 | /* Iterate over AS_PATH segments and wipe all occurrences of the |
841f7a57 DO |
1472 | * listed AS numbers. Hence some segments may lose some or even |
1473 | * all data on the way, the operation is implemented as a smarter | |
1474 | * version of aspath_dup(), which allocates memory to hold the new | |
1475 | * data, not the original. The new AS path is returned. | |
1476 | */ | |
d62a17ae | 1477 | struct aspath *aspath_filter_exclude(struct aspath *source, |
1478 | struct aspath *exclude_list) | |
1479 | { | |
1480 | struct assegment *srcseg, *exclseg, *lastseg; | |
1481 | struct aspath *newpath; | |
1482 | ||
1483 | newpath = aspath_new(); | |
1484 | lastseg = NULL; | |
1485 | ||
1486 | for (srcseg = source->segments; srcseg; srcseg = srcseg->next) { | |
1487 | unsigned i, y, newlen = 0, done = 0, skip_as; | |
1488 | struct assegment *newseg; | |
1489 | ||
1490 | /* Find out, how much ASns are we going to pick from this | |
1491 | * segment. | |
1492 | * We can't perform filtering right inline, because the size of | |
1493 | * the new segment isn't known at the moment yet. | |
1494 | */ | |
1495 | for (i = 0; i < srcseg->length; i++) { | |
1496 | skip_as = 0; | |
1497 | for (exclseg = exclude_list->segments; | |
1498 | exclseg && !skip_as; exclseg = exclseg->next) | |
1499 | for (y = 0; y < exclseg->length; y++) | |
1500 | if (srcseg->as[i] == exclseg->as[y]) { | |
1501 | skip_as = 1; | |
1502 | // There's no sense in testing | |
1503 | // the rest of exclusion list, | |
1504 | // bail out. | |
1505 | break; | |
1506 | } | |
1507 | if (!skip_as) | |
1508 | newlen++; | |
1509 | } | |
1510 | /* newlen is now the number of ASns to copy */ | |
1511 | if (!newlen) | |
1512 | continue; | |
1513 | ||
1514 | /* Actual copying. Allocate memory and iterate once more, | |
1515 | * performing filtering. */ | |
1516 | newseg = assegment_new(srcseg->type, newlen); | |
1517 | for (i = 0; i < srcseg->length; i++) { | |
1518 | skip_as = 0; | |
1519 | for (exclseg = exclude_list->segments; | |
1520 | exclseg && !skip_as; exclseg = exclseg->next) | |
1521 | for (y = 0; y < exclseg->length; y++) | |
1522 | if (srcseg->as[i] == exclseg->as[y]) { | |
1523 | skip_as = 1; | |
1524 | break; | |
1525 | } | |
1526 | if (skip_as) | |
1527 | continue; | |
1528 | newseg->as[done++] = srcseg->as[i]; | |
1529 | } | |
1530 | /* At his point newlen must be equal to done, and both must be | |
1531 | * positive. Append | |
1532 | * the filtered segment to the gross result. */ | |
1533 | if (!lastseg) | |
1534 | newpath->segments = newseg; | |
1535 | else | |
1536 | lastseg->next = newseg; | |
1537 | lastseg = newseg; | |
1538 | } | |
68e1a55b | 1539 | aspath_str_update(newpath, false); |
d62a17ae | 1540 | /* We are happy returning even an empty AS_PATH, because the |
1541 | * administrator | |
1542 | * might expect this very behaviour. There's a mean to avoid this, if | |
1543 | * necessary, | |
1544 | * by having a match rule against certain AS_PATH regexps in the | |
1545 | * route-map index. | |
1546 | */ | |
1547 | aspath_free(source); | |
1548 | return newpath; | |
841f7a57 DO |
1549 | } |
1550 | ||
718e3744 | 1551 | /* Add specified AS to the leftmost of aspath. */ |
d62a17ae | 1552 | static struct aspath *aspath_add_asns(struct aspath *aspath, as_t asno, |
d7c0a89a | 1553 | uint8_t type, unsigned num) |
d62a17ae | 1554 | { |
1555 | struct assegment *assegment = aspath->segments; | |
1556 | unsigned i; | |
1557 | ||
1558 | if (assegment && assegment->type == type) { | |
1559 | /* extend existing segment */ | |
1560 | aspath->segments = | |
1561 | assegment_prepend_asns(aspath->segments, asno, num); | |
1562 | } else { | |
1563 | /* prepend with new segment */ | |
1564 | struct assegment *newsegment = assegment_new(type, num); | |
1565 | for (i = 0; i < num; i++) | |
1566 | newsegment->as[i] = asno; | |
1567 | ||
1568 | /* insert potentially replacing empty segment */ | |
1569 | if (assegment && assegment->length == 0) { | |
1570 | newsegment->next = assegment->next; | |
1571 | assegment_free(assegment); | |
1572 | } else | |
1573 | newsegment->next = assegment; | |
1574 | aspath->segments = newsegment; | |
bc3dd427 | 1575 | } |
718e3744 | 1576 | |
68e1a55b | 1577 | aspath_str_update(aspath, false); |
d62a17ae | 1578 | return aspath; |
718e3744 | 1579 | } |
1580 | ||
bc3dd427 | 1581 | /* Add specified AS to the leftmost of aspath num times. */ |
d62a17ae | 1582 | struct aspath *aspath_add_seq_n(struct aspath *aspath, as_t asno, unsigned num) |
bc3dd427 | 1583 | { |
d62a17ae | 1584 | return aspath_add_asns(aspath, asno, AS_SEQUENCE, num); |
bc3dd427 DW |
1585 | } |
1586 | ||
718e3744 | 1587 | /* Add specified AS to the leftmost of aspath. */ |
d62a17ae | 1588 | struct aspath *aspath_add_seq(struct aspath *aspath, as_t asno) |
718e3744 | 1589 | { |
d62a17ae | 1590 | return aspath_add_asns(aspath, asno, AS_SEQUENCE, 1); |
718e3744 | 1591 | } |
1592 | ||
1593 | /* Compare leftmost AS value for MED check. If as1's leftmost AS and | |
1594 | as2's leftmost AS is same return 1. */ | |
d62a17ae | 1595 | int aspath_cmp_left(const struct aspath *aspath1, const struct aspath *aspath2) |
718e3744 | 1596 | { |
d62a17ae | 1597 | const struct assegment *seg1; |
1598 | const struct assegment *seg2; | |
1599 | ||
1600 | if (!(aspath1 && aspath2)) | |
1601 | return 0; | |
718e3744 | 1602 | |
d62a17ae | 1603 | seg1 = aspath1->segments; |
1604 | seg2 = aspath2->segments; | |
718e3744 | 1605 | |
d62a17ae | 1606 | /* If both paths are originated in this AS then we do want to compare |
1607 | * MED */ | |
1608 | if (!seg1 && !seg2) | |
1609 | return 1; | |
718e3744 | 1610 | |
d62a17ae | 1611 | /* find first non-confed segments for each */ |
9d303b37 DL |
1612 | while (seg1 && ((seg1->type == AS_CONFED_SEQUENCE) |
1613 | || (seg1->type == AS_CONFED_SET))) | |
d62a17ae | 1614 | seg1 = seg1->next; |
2a3fa5d7 | 1615 | |
9d303b37 DL |
1616 | while (seg2 && ((seg2->type == AS_CONFED_SEQUENCE) |
1617 | || (seg2->type == AS_CONFED_SET))) | |
d62a17ae | 1618 | seg2 = seg2->next; |
718e3744 | 1619 | |
d62a17ae | 1620 | /* Check as1's */ |
1621 | if (!(seg1 && seg2 && (seg1->type == AS_SEQUENCE) | |
1622 | && (seg2->type == AS_SEQUENCE))) | |
1623 | return 0; | |
718e3744 | 1624 | |
d62a17ae | 1625 | if (seg1->as[0] == seg2->as[0]) |
1626 | return 1; | |
718e3744 | 1627 | |
d62a17ae | 1628 | return 0; |
718e3744 | 1629 | } |
1630 | ||
0b2aa3a0 PJ |
1631 | /* Truncate an aspath after a number of hops, and put the hops remaining |
1632 | * at the front of another aspath. Needed for AS4 compat. | |
1633 | * | |
1634 | * Returned aspath is a /new/ aspath, which should either by free'd or | |
1635 | * interned by the caller, as desired. | |
1636 | */ | |
d62a17ae | 1637 | struct aspath *aspath_reconcile_as4(struct aspath *aspath, |
1638 | struct aspath *as4path) | |
1639 | { | |
1640 | struct assegment *seg, *newseg, *prevseg = NULL; | |
1641 | struct aspath *newpath = NULL, *mergedpath; | |
1642 | int hops, cpasns = 0; | |
1643 | ||
e8a3a0a0 | 1644 | if (!aspath || !as4path) |
d62a17ae | 1645 | return NULL; |
1646 | ||
1647 | seg = aspath->segments; | |
1648 | ||
1649 | /* CONFEDs should get reconciled too.. */ | |
1650 | hops = (aspath_count_hops(aspath) + aspath_count_confeds(aspath)) | |
1651 | - aspath_count_hops(as4path); | |
1652 | ||
1653 | if (hops < 0) { | |
1654 | if (BGP_DEBUG(as4, AS4)) | |
ade6974d | 1655 | flog_warn( |
e50f7cfd | 1656 | EC_BGP_ASPATH_FEWER_HOPS, |
ade6974d | 1657 | "[AS4] Fewer hops in AS_PATH than NEW_AS_PATH"); |
d62a17ae | 1658 | /* Something's gone wrong. The RFC says we should now ignore |
1659 | * AS4_PATH, | |
1660 | * which is daft behaviour - it contains vital loop-detection | |
1661 | * information which must have been removed from AS_PATH. | |
1662 | */ | |
1663 | hops = aspath_count_hops(aspath); | |
1664 | } | |
1665 | ||
1666 | if (!hops) { | |
1667 | newpath = aspath_dup(as4path); | |
68e1a55b | 1668 | aspath_str_update(newpath, false); |
d62a17ae | 1669 | return newpath; |
0b2aa3a0 | 1670 | } |
d62a17ae | 1671 | |
1672 | if (BGP_DEBUG(as4, AS4)) | |
1673 | zlog_debug( | |
1674 | "[AS4] got AS_PATH %s and AS4_PATH %s synthesizing now", | |
1675 | aspath->str, as4path->str); | |
1676 | ||
1677 | while (seg && hops > 0) { | |
1678 | switch (seg->type) { | |
1679 | case AS_SET: | |
1680 | case AS_CONFED_SET: | |
1681 | hops--; | |
1682 | cpasns = seg->length; | |
1683 | break; | |
1684 | case AS_CONFED_SEQUENCE: | |
1685 | /* Should never split a confed-sequence, if hop-count | |
1686 | * suggests we must then something's gone wrong | |
1687 | * somewhere. | |
1688 | * | |
1689 | * Most important goal is to preserve AS_PATHs prime | |
1690 | * function | |
1691 | * as loop-detector, so we fudge the numbers so that the | |
1692 | * entire | |
1693 | * confed-sequence is merged in. | |
1694 | */ | |
1695 | if (hops < seg->length) { | |
1696 | if (BGP_DEBUG(as4, AS4)) | |
1697 | zlog_debug( | |
1698 | "[AS4] AS4PATHmangle: AS_CONFED_SEQUENCE falls" | |
1699 | " across 2/4 ASN boundary somewhere, broken.."); | |
1700 | hops = seg->length; | |
1701 | } | |
1702 | /* fallthru */ | |
1703 | case AS_SEQUENCE: | |
1704 | cpasns = MIN(seg->length, hops); | |
1705 | hops -= seg->length; | |
1706 | } | |
1707 | ||
1708 | assert(cpasns <= seg->length); | |
1709 | ||
1710 | newseg = assegment_new(seg->type, 0); | |
1711 | newseg = assegment_append_asns(newseg, seg->as, cpasns); | |
1712 | ||
1713 | if (!newpath) { | |
1714 | newpath = aspath_new(); | |
1715 | newpath->segments = newseg; | |
1716 | } else | |
1717 | prevseg->next = newseg; | |
1718 | ||
1719 | prevseg = newseg; | |
1720 | seg = seg->next; | |
1721 | } | |
1722 | ||
1723 | /* We may be able to join some segments here, and we must | |
1724 | * do this because... we want normalised aspaths in out hash | |
1725 | * and we do not want to stumble in aspath_put. | |
1726 | */ | |
1727 | mergedpath = aspath_merge(newpath, aspath_dup(as4path)); | |
1728 | aspath_free(newpath); | |
1729 | mergedpath->segments = assegment_normalise(mergedpath->segments); | |
68e1a55b | 1730 | aspath_str_update(mergedpath, false); |
d62a17ae | 1731 | |
1732 | if (BGP_DEBUG(as4, AS4)) | |
1733 | zlog_debug("[AS4] result of synthesizing is %s", | |
1734 | mergedpath->str); | |
1735 | ||
1736 | return mergedpath; | |
0b2aa3a0 PJ |
1737 | } |
1738 | ||
718e3744 | 1739 | /* Compare leftmost AS value for MED check. If as1's leftmost AS and |
1740 | as2's leftmost AS is same return 1. (confederation as-path | |
1741 | only). */ | |
74df8d6d DS |
1742 | bool aspath_cmp_left_confed(const struct aspath *aspath1, |
1743 | const struct aspath *aspath2) | |
718e3744 | 1744 | { |
d62a17ae | 1745 | if (!(aspath1 && aspath2)) |
74df8d6d | 1746 | return false; |
718e3744 | 1747 | |
d62a17ae | 1748 | if (!(aspath1->segments && aspath2->segments)) |
74df8d6d | 1749 | return false; |
d62a17ae | 1750 | |
1751 | if ((aspath1->segments->type != AS_CONFED_SEQUENCE) | |
1752 | || (aspath2->segments->type != AS_CONFED_SEQUENCE)) | |
74df8d6d | 1753 | return false; |
d62a17ae | 1754 | |
1755 | if (aspath1->segments->as[0] == aspath2->segments->as[0]) | |
74df8d6d | 1756 | return true; |
d62a17ae | 1757 | |
74df8d6d | 1758 | return false; |
718e3744 | 1759 | } |
1760 | ||
66b199b2 DS |
1761 | /* Delete all AS_CONFED_SEQUENCE/SET segments from aspath. |
1762 | * RFC 5065 section 4.1.c.1 | |
1763 | * | |
1764 | * 1) if any path segments of the AS_PATH are of the type | |
1765 | * AS_CONFED_SEQUENCE or AS_CONFED_SET, those segments MUST be | |
1766 | * removed from the AS_PATH attribute, leaving the sanitized | |
1767 | * AS_PATH attribute to be operated on by steps 2, 3 or 4. | |
1768 | */ | |
d62a17ae | 1769 | struct aspath *aspath_delete_confed_seq(struct aspath *aspath) |
718e3744 | 1770 | { |
d62a17ae | 1771 | struct assegment *seg, *prev, *next; |
1772 | char removed_confed_segment; | |
1773 | ||
1774 | if (!(aspath && aspath->segments)) | |
1775 | return aspath; | |
718e3744 | 1776 | |
d62a17ae | 1777 | seg = aspath->segments; |
1778 | removed_confed_segment = 0; | |
1779 | next = NULL; | |
1780 | prev = NULL; | |
718e3744 | 1781 | |
d62a17ae | 1782 | while (seg) { |
1783 | next = seg->next; | |
66b199b2 | 1784 | |
d62a17ae | 1785 | if (seg->type == AS_CONFED_SEQUENCE |
1786 | || seg->type == AS_CONFED_SET) { | |
1787 | /* This is the first segment in the aspath */ | |
1788 | if (aspath->segments == seg) | |
1789 | aspath->segments = seg->next; | |
1790 | else | |
1791 | prev->next = seg->next; | |
66b199b2 | 1792 | |
d62a17ae | 1793 | assegment_free(seg); |
1794 | removed_confed_segment = 1; | |
1795 | } else | |
1796 | prev = seg; | |
66b199b2 | 1797 | |
d62a17ae | 1798 | seg = next; |
1799 | } | |
66b199b2 | 1800 | |
d62a17ae | 1801 | if (removed_confed_segment) |
68e1a55b | 1802 | aspath_str_update(aspath, false); |
66b199b2 | 1803 | |
d62a17ae | 1804 | return aspath; |
718e3744 | 1805 | } |
1806 | ||
1807 | /* Add new AS number to the leftmost part of the aspath as | |
1808 | AS_CONFED_SEQUENCE. */ | |
d62a17ae | 1809 | struct aspath *aspath_add_confed_seq(struct aspath *aspath, as_t asno) |
718e3744 | 1810 | { |
d62a17ae | 1811 | return aspath_add_asns(aspath, asno, AS_CONFED_SEQUENCE, 1); |
718e3744 | 1812 | } |
1813 | ||
1814 | /* Add new as value to as path structure. */ | |
d62a17ae | 1815 | static void aspath_as_add(struct aspath *as, as_t asno) |
718e3744 | 1816 | { |
d62a17ae | 1817 | struct assegment *seg = as->segments; |
1818 | ||
1819 | if (!seg) | |
1820 | return; | |
718e3744 | 1821 | |
d62a17ae | 1822 | /* Last segment search procedure. */ |
1823 | while (seg->next) | |
1824 | seg = seg->next; | |
93c1749c | 1825 | |
d62a17ae | 1826 | assegment_append_asns(seg, &asno, 1); |
718e3744 | 1827 | } |
1828 | ||
1829 | /* Add new as segment to the as path. */ | |
d62a17ae | 1830 | static void aspath_segment_add(struct aspath *as, int type) |
718e3744 | 1831 | { |
d62a17ae | 1832 | struct assegment *seg = as->segments; |
1833 | struct assegment *new = assegment_new(type, 0); | |
718e3744 | 1834 | |
d62a17ae | 1835 | if (seg) { |
1836 | while (seg->next) | |
1837 | seg = seg->next; | |
1838 | seg->next = new; | |
1839 | } else | |
1840 | as->segments = new; | |
718e3744 | 1841 | } |
1842 | ||
d62a17ae | 1843 | struct aspath *aspath_empty(void) |
718e3744 | 1844 | { |
d62a17ae | 1845 | return aspath_parse(NULL, 0, 1); /* 32Bit ;-) */ |
718e3744 | 1846 | } |
1847 | ||
d62a17ae | 1848 | struct aspath *aspath_empty_get(void) |
718e3744 | 1849 | { |
d62a17ae | 1850 | struct aspath *aspath; |
718e3744 | 1851 | |
d62a17ae | 1852 | aspath = aspath_new(); |
68e1a55b | 1853 | aspath_make_str_count(aspath, false); |
d62a17ae | 1854 | return aspath; |
718e3744 | 1855 | } |
1856 | ||
d62a17ae | 1857 | unsigned long aspath_count(void) |
718e3744 | 1858 | { |
d62a17ae | 1859 | return ashash->count; |
1860 | } | |
6b0655a2 | 1861 | |
d62a17ae | 1862 | /* |
718e3744 | 1863 | Theoretically, one as path can have: |
1864 | ||
1865 | One BGP packet size should be less than 4096. | |
1866 | One BGP attribute size should be less than 4096 - BGP header size. | |
1867 | One BGP aspath size should be less than 4096 - BGP header size - | |
1868 | BGP mandantry attribute size. | |
1869 | */ | |
1870 | ||
1871 | /* AS path string lexical token enum. */ | |
d62a17ae | 1872 | enum as_token { |
1873 | as_token_asval, | |
1874 | as_token_set_start, | |
1875 | as_token_set_end, | |
1876 | as_token_confed_seq_start, | |
1877 | as_token_confed_seq_end, | |
1878 | as_token_confed_set_start, | |
1879 | as_token_confed_set_end, | |
1880 | as_token_unknown | |
718e3744 | 1881 | }; |
1882 | ||
1883 | /* Return next token and point for string parse. */ | |
d62a17ae | 1884 | static const char *aspath_gettoken(const char *buf, enum as_token *token, |
d7c0a89a | 1885 | unsigned long *asno) |
d62a17ae | 1886 | { |
1887 | const char *p = buf; | |
1888 | ||
1889 | /* Skip seperators (space for sequences, ',' for sets). */ | |
fefa5e0f | 1890 | while (isspace((unsigned char)*p) || *p == ',') |
d62a17ae | 1891 | p++; |
1892 | ||
1893 | /* Check the end of the string and type specify characters | |
1894 | (e.g. {}()). */ | |
1895 | switch (*p) { | |
1896 | case '\0': | |
1897 | return NULL; | |
1898 | case '{': | |
1899 | *token = as_token_set_start; | |
1900 | p++; | |
1901 | return p; | |
1902 | case '}': | |
1903 | *token = as_token_set_end; | |
1904 | p++; | |
1905 | return p; | |
1906 | case '(': | |
1907 | *token = as_token_confed_seq_start; | |
1908 | p++; | |
1909 | return p; | |
1910 | case ')': | |
1911 | *token = as_token_confed_seq_end; | |
1912 | p++; | |
1913 | return p; | |
1914 | case '[': | |
1915 | *token = as_token_confed_set_start; | |
1916 | p++; | |
1917 | return p; | |
1918 | case ']': | |
1919 | *token = as_token_confed_set_end; | |
1920 | p++; | |
1921 | return p; | |
1922 | } | |
1923 | ||
1924 | /* Check actual AS value. */ | |
fefa5e0f | 1925 | if (isdigit((unsigned char)*p)) { |
d62a17ae | 1926 | as_t asval; |
1927 | ||
1928 | *token = as_token_asval; | |
1929 | asval = (*p - '0'); | |
1930 | p++; | |
1931 | ||
fefa5e0f | 1932 | while (isdigit((unsigned char)*p)) { |
d62a17ae | 1933 | asval *= 10; |
1934 | asval += (*p - '0'); | |
1935 | p++; | |
1936 | } | |
1937 | *asno = asval; | |
1938 | return p; | |
718e3744 | 1939 | } |
718e3744 | 1940 | |
d62a17ae | 1941 | /* There is no match then return unknown token. */ |
1942 | *token = as_token_unknown; | |
b42d80dd VJ |
1943 | p++; |
1944 | return p; | |
d62a17ae | 1945 | } |
1946 | ||
1947 | struct aspath *aspath_str2aspath(const char *str) | |
1948 | { | |
1949 | enum as_token token = as_token_unknown; | |
d7c0a89a QY |
1950 | unsigned short as_type; |
1951 | unsigned long asno = 0; | |
d62a17ae | 1952 | struct aspath *aspath; |
1953 | int needtype; | |
1954 | ||
1955 | aspath = aspath_new(); | |
1956 | ||
1957 | /* We start default type as AS_SEQUENCE. */ | |
1958 | as_type = AS_SEQUENCE; | |
1959 | needtype = 1; | |
1960 | ||
1961 | while ((str = aspath_gettoken(str, &token, &asno)) != NULL) { | |
1962 | switch (token) { | |
1963 | case as_token_asval: | |
1964 | if (needtype) { | |
1965 | aspath_segment_add(aspath, as_type); | |
1966 | needtype = 0; | |
1967 | } | |
1968 | aspath_as_add(aspath, asno); | |
1969 | break; | |
1970 | case as_token_set_start: | |
1971 | as_type = AS_SET; | |
1972 | aspath_segment_add(aspath, as_type); | |
1973 | needtype = 0; | |
1974 | break; | |
1975 | case as_token_set_end: | |
1976 | as_type = AS_SEQUENCE; | |
1977 | needtype = 1; | |
1978 | break; | |
1979 | case as_token_confed_seq_start: | |
1980 | as_type = AS_CONFED_SEQUENCE; | |
1981 | aspath_segment_add(aspath, as_type); | |
1982 | needtype = 0; | |
1983 | break; | |
1984 | case as_token_confed_seq_end: | |
1985 | as_type = AS_SEQUENCE; | |
1986 | needtype = 1; | |
1987 | break; | |
1988 | case as_token_confed_set_start: | |
1989 | as_type = AS_CONFED_SET; | |
1990 | aspath_segment_add(aspath, as_type); | |
1991 | needtype = 0; | |
1992 | break; | |
1993 | case as_token_confed_set_end: | |
1994 | as_type = AS_SEQUENCE; | |
1995 | needtype = 1; | |
1996 | break; | |
1997 | case as_token_unknown: | |
1998 | default: | |
1999 | aspath_free(aspath); | |
2000 | return NULL; | |
2001 | } | |
2002 | } | |
2003 | ||
68e1a55b | 2004 | aspath_make_str_count(aspath, false); |
718e3744 | 2005 | |
d62a17ae | 2006 | return aspath; |
718e3744 | 2007 | } |
6b0655a2 | 2008 | |
718e3744 | 2009 | /* Make hash value by raw aspath data. */ |
d8b87afe | 2010 | unsigned int aspath_key_make(const void *p) |
718e3744 | 2011 | { |
d8b87afe | 2012 | const struct aspath *aspath = p; |
d62a17ae | 2013 | unsigned int key = 0; |
718e3744 | 2014 | |
d62a17ae | 2015 | if (!aspath->str) |
d8b87afe | 2016 | aspath_str_update((struct aspath *)aspath, false); |
f669f7d2 | 2017 | |
d62a17ae | 2018 | key = jhash(aspath->str, aspath->str_len, 2334325); |
718e3744 | 2019 | |
d62a17ae | 2020 | return key; |
718e3744 | 2021 | } |
2022 | ||
2023 | /* If two aspath have same value then return 1 else return 0 */ | |
74df8d6d | 2024 | bool aspath_cmp(const void *arg1, const void *arg2) |
d62a17ae | 2025 | { |
2026 | const struct assegment *seg1 = ((const struct aspath *)arg1)->segments; | |
2027 | const struct assegment *seg2 = ((const struct aspath *)arg2)->segments; | |
2028 | ||
2029 | while (seg1 || seg2) { | |
2030 | int i; | |
2031 | if ((!seg1 && seg2) || (seg1 && !seg2)) | |
74df8d6d | 2032 | return false; |
d62a17ae | 2033 | if (seg1->type != seg2->type) |
74df8d6d | 2034 | return false; |
d62a17ae | 2035 | if (seg1->length != seg2->length) |
74df8d6d | 2036 | return false; |
d62a17ae | 2037 | for (i = 0; i < seg1->length; i++) |
2038 | if (seg1->as[i] != seg2->as[i]) | |
74df8d6d | 2039 | return false; |
d62a17ae | 2040 | seg1 = seg1->next; |
2041 | seg2 = seg2->next; | |
2042 | } | |
74df8d6d | 2043 | return true; |
718e3744 | 2044 | } |
2045 | ||
2046 | /* AS path hash initialize. */ | |
d62a17ae | 2047 | void aspath_init(void) |
718e3744 | 2048 | { |
996c9314 | 2049 | ashash = hash_create_size(32768, aspath_key_make, aspath_cmp, |
3f65c5b1 | 2050 | "BGP AS Path"); |
718e3744 | 2051 | } |
8fdc32ab | 2052 | |
d62a17ae | 2053 | void aspath_finish(void) |
8fdc32ab | 2054 | { |
d62a17ae | 2055 | hash_clean(ashash, (void (*)(void *))aspath_free); |
2056 | hash_free(ashash); | |
2057 | ashash = NULL; | |
2058 | ||
2059 | if (snmp_stream) | |
2060 | stream_free(snmp_stream); | |
8fdc32ab | 2061 | } |
6b0655a2 | 2062 | |
718e3744 | 2063 | /* return and as path value */ |
d62a17ae | 2064 | const char *aspath_print(struct aspath *as) |
718e3744 | 2065 | { |
d62a17ae | 2066 | return (as ? as->str : NULL); |
718e3744 | 2067 | } |
2068 | ||
2069 | /* Printing functions */ | |
841f7a57 DO |
2070 | /* Feed the AS_PATH to the vty; the suffix string follows it only in case |
2071 | * AS_PATH wasn't empty. | |
2072 | */ | |
d62a17ae | 2073 | void aspath_print_vty(struct vty *vty, const char *format, struct aspath *as, |
2074 | const char *suffix) | |
718e3744 | 2075 | { |
d62a17ae | 2076 | assert(format); |
2077 | vty_out(vty, format, as->str); | |
2078 | if (as->str_len && strlen(suffix)) | |
2079 | vty_out(vty, "%s", suffix); | |
718e3744 | 2080 | } |
2081 | ||
e3b78da8 | 2082 | static void aspath_show_all_iterator(struct hash_bucket *bucket, |
d62a17ae | 2083 | struct vty *vty) |
718e3744 | 2084 | { |
d62a17ae | 2085 | struct aspath *as; |
718e3744 | 2086 | |
e3b78da8 | 2087 | as = (struct aspath *)bucket->data; |
718e3744 | 2088 | |
e3b78da8 | 2089 | vty_out(vty, "[%p:%u] (%ld) ", (void *)bucket, bucket->key, as->refcnt); |
d62a17ae | 2090 | vty_out(vty, "%s\n", as->str); |
718e3744 | 2091 | } |
2092 | ||
2093 | /* Print all aspath and hash information. This function is used from | |
716b2d8a | 2094 | `show [ip] bgp paths' command. */ |
d62a17ae | 2095 | void aspath_print_all_vty(struct vty *vty) |
718e3744 | 2096 | { |
e3b78da8 | 2097 | hash_iterate(ashash, (void (*)(struct hash_bucket *, |
9d303b37 | 2098 | void *))aspath_show_all_iterator, |
d62a17ae | 2099 | vty); |
718e3744 | 2100 | } |
e00d8008 NT |
2101 | |
2102 | static struct aspath *bgp_aggr_aspath_lookup(struct bgp_aggregate *aggregate, | |
2103 | struct aspath *aspath) | |
2104 | { | |
2105 | return hash_lookup(aggregate->aspath_hash, aspath); | |
2106 | } | |
2107 | ||
2108 | static void *bgp_aggr_aspath_hash_alloc(void *p) | |
2109 | { | |
2110 | struct aspath *ref = (struct aspath *)p; | |
2111 | struct aspath *aspath = NULL; | |
2112 | ||
2113 | aspath = aspath_dup(ref); | |
2114 | return aspath; | |
2115 | } | |
2116 | ||
2117 | static void bgp_aggr_aspath_prepare(struct hash_backet *hb, void *arg) | |
2118 | { | |
e00d8008 NT |
2119 | struct aspath *hb_aspath = hb->data; |
2120 | struct aspath **aggr_aspath = arg; | |
2121 | ||
ef51a7d8 | 2122 | if (*aggr_aspath) |
2123 | *aggr_aspath = aspath_aggregate(*aggr_aspath, hb_aspath); | |
2124 | else | |
e00d8008 NT |
2125 | *aggr_aspath = aspath_dup(hb_aspath); |
2126 | } | |
2127 | ||
2128 | void bgp_aggr_aspath_remove(void *arg) | |
2129 | { | |
2130 | struct aspath *aspath = arg; | |
2131 | ||
2132 | aspath_free(aspath); | |
2133 | } | |
2134 | ||
2135 | void bgp_compute_aggregate_aspath(struct bgp_aggregate *aggregate, | |
2136 | struct aspath *aspath) | |
ef51a7d8 | 2137 | { |
2138 | bgp_compute_aggregate_aspath_hash(aggregate, aspath); | |
2139 | ||
2140 | bgp_compute_aggregate_aspath_val(aggregate); | |
2141 | ||
2142 | } | |
2143 | ||
2144 | void bgp_compute_aggregate_aspath_hash(struct bgp_aggregate *aggregate, | |
2145 | struct aspath *aspath) | |
e00d8008 NT |
2146 | { |
2147 | struct aspath *aggr_aspath = NULL; | |
2148 | ||
2149 | if ((aggregate == NULL) || (aspath == NULL)) | |
2150 | return; | |
2151 | ||
2152 | /* Create hash if not already created. | |
2153 | */ | |
2154 | if (aggregate->aspath_hash == NULL) | |
2155 | aggregate->aspath_hash = hash_create( | |
2156 | aspath_key_make, aspath_cmp, | |
2157 | "BGP Aggregator as-path hash"); | |
2158 | ||
2159 | aggr_aspath = bgp_aggr_aspath_lookup(aggregate, aspath); | |
2160 | if (aggr_aspath == NULL) { | |
2161 | /* Insert as-path into hash. | |
2162 | */ | |
2163 | aggr_aspath = hash_get(aggregate->aspath_hash, aspath, | |
2164 | bgp_aggr_aspath_hash_alloc); | |
ef51a7d8 | 2165 | } |
e00d8008 | 2166 | |
ef51a7d8 | 2167 | /* Increment reference counter. |
2168 | */ | |
2169 | aggr_aspath->refcnt++; | |
2170 | } | |
2171 | ||
2172 | void bgp_compute_aggregate_aspath_val(struct bgp_aggregate *aggregate) | |
2173 | { | |
2174 | if (aggregate == NULL) | |
2175 | return; | |
2176 | /* Re-compute aggregate's as-path. | |
2177 | */ | |
2178 | if (aggregate->aspath) { | |
2179 | aspath_free(aggregate->aspath); | |
2180 | aggregate->aspath = NULL; | |
2181 | } | |
2182 | if (aggregate->aspath_hash | |
2183 | && aggregate->aspath_hash->count) { | |
e00d8008 NT |
2184 | hash_iterate(aggregate->aspath_hash, |
2185 | bgp_aggr_aspath_prepare, | |
2186 | &aggregate->aspath); | |
2187 | } | |
e00d8008 NT |
2188 | } |
2189 | ||
2190 | void bgp_remove_aspath_from_aggregate(struct bgp_aggregate *aggregate, | |
2191 | struct aspath *aspath) | |
2192 | { | |
2193 | struct aspath *aggr_aspath = NULL; | |
2194 | struct aspath *ret_aspath = NULL; | |
2195 | ||
ef51a7d8 | 2196 | if ((!aggregate) |
2197 | || (!aggregate->aspath_hash) | |
2198 | || (!aspath)) | |
e00d8008 NT |
2199 | return; |
2200 | ||
2201 | /* Look-up the aspath in the hash. | |
2202 | */ | |
2203 | aggr_aspath = bgp_aggr_aspath_lookup(aggregate, aspath); | |
2204 | if (aggr_aspath) { | |
2205 | aggr_aspath->refcnt--; | |
2206 | ||
2207 | if (aggr_aspath->refcnt == 0) { | |
2208 | ret_aspath = hash_release(aggregate->aspath_hash, | |
2209 | aggr_aspath); | |
2210 | aspath_free(ret_aspath); | |
ef51a7d8 | 2211 | ret_aspath = NULL; |
e00d8008 NT |
2212 | |
2213 | /* Remove aggregate's old as-path. | |
2214 | */ | |
2215 | aspath_free(aggregate->aspath); | |
2216 | aggregate->aspath = NULL; | |
2217 | ||
ef51a7d8 | 2218 | bgp_compute_aggregate_aspath_val(aggregate); |
e00d8008 NT |
2219 | } |
2220 | } | |
2221 | } | |
ef51a7d8 | 2222 | |
2223 | void bgp_remove_aspath_from_aggregate_hash(struct bgp_aggregate *aggregate, | |
2224 | struct aspath *aspath) | |
2225 | { | |
2226 | struct aspath *aggr_aspath = NULL; | |
2227 | struct aspath *ret_aspath = NULL; | |
2228 | ||
2229 | if ((!aggregate) | |
2230 | || (!aggregate->aspath_hash) | |
2231 | || (!aspath)) | |
2232 | return; | |
2233 | ||
2234 | /* Look-up the aspath in the hash. | |
2235 | */ | |
2236 | aggr_aspath = bgp_aggr_aspath_lookup(aggregate, aspath); | |
2237 | if (aggr_aspath) { | |
2238 | aggr_aspath->refcnt--; | |
2239 | ||
2240 | if (aggr_aspath->refcnt == 0) { | |
2241 | ret_aspath = hash_release(aggregate->aspath_hash, | |
2242 | aggr_aspath); | |
2243 | aspath_free(ret_aspath); | |
2244 | ret_aspath = NULL; | |
2245 | } | |
2246 | } | |
2247 | } | |
2248 |