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718e3744 | 1 | /* AS path management routines. |
2 | Copyright (C) 1996, 97, 98, 99 Kunihiro Ishiguro | |
fe69a505 | 3 | Copyright (C) 2005 Sun Microsystems, Inc. |
718e3744 | 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 | |
18 | along with GNU Zebra; see the file COPYING. If not, write to the Free | |
19 | Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA | |
20 | 02111-1307, USA. */ | |
21 | ||
22 | #include <zebra.h> | |
23 | ||
24 | #include "hash.h" | |
25 | #include "memory.h" | |
26 | #include "vector.h" | |
27 | #include "vty.h" | |
28 | #include "str.h" | |
29 | #include "log.h" | |
fe69a505 | 30 | #include "stream.h" |
0b2aa3a0 | 31 | #include "jhash.h" |
718e3744 | 32 | |
33 | #include "bgpd/bgpd.h" | |
34 | #include "bgpd/bgp_aspath.h" | |
0b2aa3a0 PJ |
35 | #include "bgpd/bgp_debug.h" |
36 | #include "bgpd/bgp_attr.h" | |
718e3744 | 37 | \f |
38 | /* Attr. Flags and Attr. Type Code. */ | |
39 | #define AS_HEADER_SIZE 2 | |
40 | ||
0b2aa3a0 | 41 | /* Now FOUR octets are used for AS value. */ |
718e3744 | 42 | #define AS_VALUE_SIZE sizeof (as_t) |
0b2aa3a0 PJ |
43 | /* This is the old one */ |
44 | #define AS16_VALUE_SIZE sizeof (as16_t) | |
718e3744 | 45 | |
fe69a505 | 46 | /* Maximum protocol segment length value */ |
47 | #define AS_SEGMENT_MAX 255 | |
48 | ||
49 | /* The following length and size macros relate specifically to Quagga's | |
50 | * internal representation of AS-Segments, not per se to the on-wire | |
51 | * sizes and lengths. At present (200508) they sort of match, however | |
52 | * the ONLY functions which should now about the on-wire syntax are | |
53 | * aspath_put, assegment_put and assegment_parse. | |
0b2aa3a0 PJ |
54 | * |
55 | * aspath_put returns bytes written, the only definitive record of | |
56 | * size of wire-format attribute.. | |
fe69a505 | 57 | */ |
58 | ||
59 | /* Calculated size in bytes of ASN segment data to hold N ASN's */ | |
0b2aa3a0 PJ |
60 | #define ASSEGMENT_DATA_SIZE(N,S) \ |
61 | ((N) * ( (S) ? AS_VALUE_SIZE : AS16_VALUE_SIZE) ) | |
718e3744 | 62 | |
fe69a505 | 63 | /* Calculated size of segment struct to hold N ASN's */ |
0b2aa3a0 | 64 | #define ASSEGMENT_SIZE(N,S) (AS_HEADER_SIZE + ASSEGMENT_DATA_SIZE (N,S)) |
fe69a505 | 65 | |
66 | /* AS segment octet length. */ | |
0b2aa3a0 | 67 | #define ASSEGMENT_LEN(X,S) ASSEGMENT_SIZE((X)->length,S) |
fe69a505 | 68 | |
69 | /* AS_SEQUENCE segments can be packed together */ | |
70 | /* Can the types of X and Y be considered for packing? */ | |
71 | #define ASSEGMENT_TYPES_PACKABLE(X,Y) \ | |
72 | ( ((X)->type == (Y)->type) \ | |
73 | && ((X)->type == AS_SEQUENCE)) | |
74 | /* Types and length of X,Y suitable for packing? */ | |
75 | #define ASSEGMENTS_PACKABLE(X,Y) \ | |
76 | ( ASSEGMENT_TYPES_PACKABLE( (X), (Y)) \ | |
77 | && ( ((X)->length + (Y)->length) <= AS_SEGMENT_MAX ) ) | |
78 | ||
79 | /* As segment header - the on-wire representation | |
80 | * NOT the internal representation! | |
81 | */ | |
82 | struct assegment_header | |
718e3744 | 83 | { |
84 | u_char type; | |
85 | u_char length; | |
718e3744 | 86 | }; |
87 | ||
88 | /* Hash for aspath. This is the top level structure of AS path. */ | |
89 | struct hash *ashash; | |
8fdc32ab | 90 | |
91 | /* Stream for SNMP. See aspath_snmp_pathseg */ | |
92 | static struct stream *snmp_stream; | |
718e3744 | 93 | \f |
fe69a505 | 94 | static inline as_t * |
95 | assegment_data_new (int num) | |
96 | { | |
0b2aa3a0 | 97 | return (XCALLOC (MTYPE_AS_SEG_DATA, ASSEGMENT_DATA_SIZE (num, 1))); |
fe69a505 | 98 | } |
99 | ||
100 | static inline void | |
101 | assegment_data_free (as_t *asdata) | |
102 | { | |
103 | XFREE (MTYPE_AS_SEG_DATA,asdata); | |
104 | } | |
105 | ||
106 | /* Get a new segment. Note that 0 is an allowed length, | |
107 | * and will result in a segment with no allocated data segment. | |
108 | * the caller should immediately assign data to the segment, as the segment | |
109 | * otherwise is not generally valid | |
110 | */ | |
111 | static struct assegment * | |
112 | assegment_new (u_char type, u_short length) | |
113 | { | |
114 | struct assegment *new; | |
115 | ||
116 | new = XCALLOC (MTYPE_AS_SEG, sizeof (struct assegment)); | |
117 | ||
118 | if (length) | |
119 | new->as = assegment_data_new (length); | |
120 | ||
121 | new->length = length; | |
122 | new->type = type; | |
123 | ||
124 | return new; | |
125 | } | |
126 | ||
127 | static void | |
128 | assegment_free (struct assegment *seg) | |
129 | { | |
130 | if (!seg) | |
131 | return; | |
132 | ||
133 | if (seg->as) | |
134 | XFREE (MTYPE_AS_SEG_DATA, seg->as); | |
135 | memset (seg, 0xfe, sizeof(struct assegment)); | |
136 | XFREE (MTYPE_AS_SEG, seg); | |
137 | ||
138 | return; | |
139 | } | |
140 | ||
141 | /* free entire chain of segments */ | |
142 | static void | |
143 | assegment_free_all (struct assegment *seg) | |
144 | { | |
145 | struct assegment *prev; | |
146 | ||
147 | while (seg) | |
148 | { | |
149 | prev = seg; | |
150 | seg = seg->next; | |
151 | assegment_free (prev); | |
152 | } | |
153 | } | |
154 | ||
155 | /* Duplicate just the given assegment and its data */ | |
156 | static struct assegment * | |
157 | assegment_dup (struct assegment *seg) | |
158 | { | |
159 | struct assegment *new; | |
160 | ||
161 | new = assegment_new (seg->type, seg->length); | |
0b2aa3a0 | 162 | memcpy (new->as, seg->as, ASSEGMENT_DATA_SIZE (new->length, 1) ); |
fe69a505 | 163 | |
164 | return new; | |
165 | } | |
166 | ||
167 | /* Duplicate entire chain of assegments, return the head */ | |
168 | static struct assegment * | |
169 | assegment_dup_all (struct assegment *seg) | |
170 | { | |
171 | struct assegment *new = NULL; | |
172 | struct assegment *head = NULL; | |
173 | ||
174 | while (seg) | |
175 | { | |
176 | if (head) | |
177 | { | |
178 | new->next = assegment_dup (seg); | |
179 | new = new->next; | |
180 | } | |
181 | else | |
182 | head = new = assegment_dup (seg); | |
183 | ||
184 | seg = seg->next; | |
185 | } | |
186 | return head; | |
187 | } | |
188 | ||
189 | /* prepend the as number to given segment, given num of times */ | |
190 | static struct assegment * | |
191 | assegment_prepend_asns (struct assegment *seg, as_t asnum, int num) | |
192 | { | |
193 | as_t *newas; | |
194 | ||
195 | if (!num) | |
196 | return seg; | |
197 | ||
198 | if (num >= AS_SEGMENT_MAX) | |
199 | return seg; /* we don't do huge prepends */ | |
200 | ||
201 | newas = assegment_data_new (seg->length + num); | |
202 | ||
203 | if (newas) | |
204 | { | |
205 | int i; | |
206 | for (i = 0; i < num; i++) | |
207 | newas[i] = asnum; | |
208 | ||
0b2aa3a0 | 209 | memcpy (newas + num, seg->as, ASSEGMENT_DATA_SIZE (seg->length, 1)); |
fe69a505 | 210 | XFREE (MTYPE_AS_SEG_DATA, seg->as); |
211 | seg->as = newas; | |
212 | seg->length += num; | |
213 | return seg; | |
214 | } | |
215 | ||
216 | assegment_free_all (seg); | |
217 | return NULL; | |
218 | } | |
219 | ||
220 | /* append given array of as numbers to the segment */ | |
221 | static struct assegment * | |
222 | assegment_append_asns (struct assegment *seg, as_t *asnos, int num) | |
223 | { | |
02335429 | 224 | as_t *newas; |
225 | ||
226 | newas = XREALLOC (MTYPE_AS_SEG_DATA, seg->as, | |
0b2aa3a0 | 227 | ASSEGMENT_DATA_SIZE (seg->length + num, 1)); |
fe69a505 | 228 | |
02335429 | 229 | if (newas) |
fe69a505 | 230 | { |
02335429 | 231 | seg->as = newas; |
0b2aa3a0 | 232 | memcpy (seg->as + seg->length, asnos, ASSEGMENT_DATA_SIZE(num, 1)); |
fe69a505 | 233 | seg->length += num; |
234 | return seg; | |
235 | } | |
236 | ||
237 | assegment_free_all (seg); | |
238 | return NULL; | |
239 | } | |
240 | ||
241 | static int | |
242 | int_cmp (const void *p1, const void *p2) | |
243 | { | |
244 | const as_t *as1 = p1; | |
245 | const as_t *as2 = p2; | |
246 | ||
247 | return (*as1 == *as2) | |
248 | ? 0 : ( (*as1 > *as2) ? 1 : -1); | |
249 | } | |
250 | ||
251 | /* normalise the segment. | |
252 | * In particular, merge runs of AS_SEQUENCEs into one segment | |
253 | * Internally, we do not care about the wire segment length limit, and | |
254 | * we want each distinct AS_PATHs to have the exact same internal | |
255 | * representation - eg, so that our hashing actually works.. | |
256 | */ | |
257 | static struct assegment * | |
258 | assegment_normalise (struct assegment *head) | |
259 | { | |
260 | struct assegment *seg = head, *pin; | |
261 | struct assegment *tmp; | |
262 | ||
263 | if (!head) | |
264 | return head; | |
265 | ||
266 | while (seg) | |
267 | { | |
268 | pin = seg; | |
269 | ||
270 | /* Sort values SET segments, for determinism in paths to aid | |
271 | * creation of hash values / path comparisons | |
272 | * and because it helps other lesser implementations ;) | |
273 | */ | |
274 | if (seg->type == AS_SET || seg->type == AS_CONFED_SET) | |
0b2aa3a0 PJ |
275 | { |
276 | int tail = 0; | |
277 | int i; | |
278 | ||
279 | qsort (seg->as, seg->length, sizeof(as_t), int_cmp); | |
280 | ||
281 | /* weed out dupes */ | |
282 | for (i=1; i < seg->length; i++) | |
283 | { | |
284 | if (seg->as[tail] == seg->as[i]) | |
285 | continue; | |
286 | ||
287 | tail++; | |
288 | if (tail < i) | |
289 | seg->as[tail] = seg->as[i]; | |
290 | } | |
291 | /* seg->length can be 0.. */ | |
292 | if (seg->length) | |
293 | seg->length = tail + 1; | |
294 | } | |
fe69a505 | 295 | |
296 | /* read ahead from the current, pinned segment while the segments | |
297 | * are packable/mergeable. Append all following packable segments | |
298 | * to the segment we have pinned and remove these appended | |
299 | * segments. | |
300 | */ | |
301 | while (pin->next && ASSEGMENT_TYPES_PACKABLE(pin, pin->next)) | |
302 | { | |
303 | tmp = pin->next; | |
304 | seg = pin->next; | |
305 | ||
306 | /* append the next sequence to the pinned sequence */ | |
307 | pin = assegment_append_asns (pin, seg->as, seg->length); | |
308 | ||
309 | /* bypass the next sequence */ | |
310 | pin->next = seg->next; | |
311 | ||
312 | /* get rid of the now referenceless segment */ | |
313 | assegment_free (tmp); | |
314 | ||
315 | } | |
316 | ||
317 | seg = pin->next; | |
318 | } | |
319 | return head; | |
320 | } | |
321 | \f | |
718e3744 | 322 | static struct aspath * |
fe69a505 | 323 | aspath_new (void) |
718e3744 | 324 | { |
393deb9b | 325 | return XCALLOC (MTYPE_AS_PATH, sizeof (struct aspath)); |
718e3744 | 326 | } |
327 | ||
328 | /* Free AS path structure. */ | |
329 | void | |
330 | aspath_free (struct aspath *aspath) | |
331 | { | |
332 | if (!aspath) | |
333 | return; | |
fe69a505 | 334 | if (aspath->segments) |
335 | assegment_free_all (aspath->segments); | |
718e3744 | 336 | if (aspath->str) |
337 | XFREE (MTYPE_AS_STR, aspath->str); | |
338 | XFREE (MTYPE_AS_PATH, aspath); | |
339 | } | |
340 | ||
341 | /* Unintern aspath from AS path bucket. */ | |
342 | void | |
343 | aspath_unintern (struct aspath *aspath) | |
344 | { | |
345 | struct aspath *ret; | |
346 | ||
347 | if (aspath->refcnt) | |
348 | aspath->refcnt--; | |
349 | ||
350 | if (aspath->refcnt == 0) | |
351 | { | |
352 | /* This aspath must exist in aspath hash table. */ | |
353 | ret = hash_release (ashash, aspath); | |
354 | assert (ret != NULL); | |
355 | aspath_free (aspath); | |
356 | } | |
357 | } | |
358 | ||
359 | /* Return the start or end delimiters for a particular Segment type */ | |
360 | #define AS_SEG_START 0 | |
361 | #define AS_SEG_END 1 | |
362 | static char | |
363 | aspath_delimiter_char (u_char type, u_char which) | |
364 | { | |
365 | int i; | |
366 | struct | |
367 | { | |
368 | int type; | |
369 | char start; | |
370 | char end; | |
371 | } aspath_delim_char [] = | |
372 | { | |
373 | { AS_SET, '{', '}' }, | |
718e3744 | 374 | { AS_CONFED_SET, '[', ']' }, |
375 | { AS_CONFED_SEQUENCE, '(', ')' }, | |
376 | { 0 } | |
377 | }; | |
378 | ||
379 | for (i = 0; aspath_delim_char[i].type != 0; i++) | |
380 | { | |
381 | if (aspath_delim_char[i].type == type) | |
382 | { | |
383 | if (which == AS_SEG_START) | |
384 | return aspath_delim_char[i].start; | |
385 | else if (which == AS_SEG_END) | |
386 | return aspath_delim_char[i].end; | |
387 | } | |
388 | } | |
389 | return ' '; | |
390 | } | |
391 | ||
014b670e DO |
392 | /* countup asns from this segment and index onward */ |
393 | static int | |
394 | assegment_count_asns (struct assegment *seg, int from) | |
395 | { | |
396 | int count = 0; | |
397 | while (seg) | |
398 | { | |
399 | if (!from) | |
400 | count += seg->length; | |
401 | else | |
402 | { | |
403 | count += (seg->length - from); | |
404 | from = 0; | |
405 | } | |
406 | seg = seg->next; | |
407 | } | |
408 | return count; | |
409 | } | |
410 | ||
fe69a505 | 411 | unsigned int |
412 | aspath_count_confeds (struct aspath *aspath) | |
413 | { | |
414 | int count = 0; | |
415 | struct assegment *seg = aspath->segments; | |
416 | ||
417 | while (seg) | |
418 | { | |
419 | if (seg->type == AS_CONFED_SEQUENCE) | |
420 | count += seg->length; | |
421 | else if (seg->type == AS_CONFED_SET) | |
422 | count++; | |
423 | ||
424 | seg = seg->next; | |
425 | } | |
426 | return count; | |
427 | } | |
428 | ||
429 | unsigned int | |
430 | aspath_count_hops (struct aspath *aspath) | |
431 | { | |
432 | int count = 0; | |
433 | struct assegment *seg = aspath->segments; | |
434 | ||
435 | while (seg) | |
436 | { | |
437 | if (seg->type == AS_SEQUENCE) | |
438 | count += seg->length; | |
439 | else if (seg->type == AS_SET) | |
440 | count++; | |
441 | ||
442 | seg = seg->next; | |
443 | } | |
444 | return count; | |
445 | } | |
446 | ||
0b2aa3a0 PJ |
447 | /* Estimate size aspath /might/ take if encoded into an |
448 | * ASPATH attribute. | |
449 | * | |
450 | * This is a quick estimate, not definitive! aspath_put() | |
451 | * may return a different number!! | |
452 | */ | |
fe69a505 | 453 | unsigned int |
454 | aspath_size (struct aspath *aspath) | |
455 | { | |
456 | int size = 0; | |
457 | struct assegment *seg = aspath->segments; | |
458 | ||
459 | while (seg) | |
460 | { | |
0b2aa3a0 | 461 | size += ASSEGMENT_SIZE(seg->length, 1); |
fe69a505 | 462 | seg = seg->next; |
463 | } | |
464 | return size; | |
465 | } | |
466 | ||
2815e61f PJ |
467 | /* Return highest public ASN in path */ |
468 | as_t | |
469 | aspath_highest (struct aspath *aspath) | |
470 | { | |
471 | struct assegment *seg = aspath->segments; | |
472 | as_t highest = 0; | |
473 | unsigned int i; | |
474 | ||
475 | while (seg) | |
476 | { | |
477 | for (i = 0; i < seg->length; i++) | |
478 | if (seg->as[i] > highest | |
479 | && (seg->as[i] < BGP_PRIVATE_AS_MIN | |
480 | || seg->as[i] > BGP_PRIVATE_AS_MAX)) | |
481 | highest = seg->as[i]; | |
482 | seg = seg->next; | |
483 | } | |
484 | return highest; | |
485 | } | |
486 | ||
0b2aa3a0 PJ |
487 | /* Return 1 if there are any 4-byte ASes in the path */ |
488 | unsigned int | |
489 | aspath_has_as4 (struct aspath *aspath) | |
490 | { | |
491 | struct assegment *seg = aspath->segments; | |
492 | unsigned int i; | |
493 | ||
494 | while (seg) | |
495 | { | |
496 | for (i = 0; i < seg->length; i++) | |
497 | if (seg->as[i] > BGP_AS_MAX) | |
498 | return 1; | |
499 | seg = seg->next; | |
500 | } | |
501 | return 0; | |
502 | } | |
503 | ||
504 | /* Return number of as numbers in in path */ | |
505 | unsigned int | |
506 | aspath_count_numas (struct aspath *aspath) | |
507 | { | |
508 | struct assegment *seg = aspath->segments; | |
509 | unsigned int num; | |
510 | ||
511 | num=0; | |
512 | while (seg) | |
513 | { | |
514 | num += seg->length; | |
515 | seg = seg->next; | |
516 | } | |
517 | return num; | |
518 | } | |
519 | ||
718e3744 | 520 | /* Convert aspath structure to string expression. */ |
94f2b392 | 521 | static char * |
718e3744 | 522 | aspath_make_str_count (struct aspath *as) |
523 | { | |
fe69a505 | 524 | struct assegment *seg; |
525 | int str_size; | |
526 | int len = 0; | |
c9e52be3 | 527 | char *str_buf; |
718e3744 | 528 | |
529 | /* Empty aspath. */ | |
fe69a505 | 530 | if (!as->segments) |
718e3744 | 531 | { |
532 | str_buf = XMALLOC (MTYPE_AS_STR, 1); | |
533 | str_buf[0] = '\0'; | |
718e3744 | 534 | return str_buf; |
535 | } | |
fe69a505 | 536 | |
537 | seg = as->segments; | |
538 | ||
014b670e DO |
539 | /* ASN takes 5 to 10 chars plus seperator, see below. |
540 | * If there is one differing segment type, we need an additional | |
541 | * 2 chars for segment delimiters, and the final '\0'. | |
542 | * Hopefully this is large enough to avoid hitting the realloc | |
543 | * code below for most common sequences. | |
544 | * | |
545 | * This was changed to 10 after the well-known BGP assertion, which | |
546 | * had hit some parts of the Internet in May of 2009. | |
547 | */ | |
548 | #define ASN_STR_LEN (10 + 1) | |
549 | str_size = MAX (assegment_count_asns (seg, 0) * ASN_STR_LEN + 2 + 1, | |
550 | ASPATH_STR_DEFAULT_LEN); | |
718e3744 | 551 | str_buf = XMALLOC (MTYPE_AS_STR, str_size); |
718e3744 | 552 | |
fe69a505 | 553 | while (seg) |
718e3744 | 554 | { |
555 | int i; | |
fe69a505 | 556 | char seperator; |
718e3744 | 557 | |
fe69a505 | 558 | /* Check AS type validity. Set seperator for segment */ |
559 | switch (seg->type) | |
560 | { | |
561 | case AS_SET: | |
562 | case AS_CONFED_SET: | |
563 | seperator = ','; | |
564 | break; | |
565 | case AS_SEQUENCE: | |
566 | case AS_CONFED_SEQUENCE: | |
567 | seperator = ' '; | |
568 | break; | |
569 | default: | |
570 | XFREE (MTYPE_AS_STR, str_buf); | |
571 | return NULL; | |
572 | } | |
573 | ||
014b670e DO |
574 | /* We might need to increase str_buf, particularly if path has |
575 | * differing segments types, our initial guesstimate above will | |
576 | * have been wrong. Need 10 chars for ASN, a seperator each and | |
577 | * potentially two segment delimiters, plus a space between each | |
578 | * segment and trailing zero. | |
579 | * | |
580 | * This definitely didn't work with the value of 5 bytes and | |
581 | * 32-bit ASNs. | |
582 | */ | |
583 | #define SEGMENT_STR_LEN(X) (((X)->length * ASN_STR_LEN) + 2 + 1 + 1) | |
584 | if ( (len + SEGMENT_STR_LEN(seg)) > str_size) | |
585 | { | |
586 | str_size = len + SEGMENT_STR_LEN(seg); | |
587 | str_buf = XREALLOC (MTYPE_AS_STR, str_buf, str_size); | |
588 | } | |
589 | #undef ASN_STR_LEN | |
590 | #undef SEGMENT_STR_LEN | |
591 | ||
fe69a505 | 592 | if (seg->type != AS_SEQUENCE) |
014b670e DO |
593 | len += snprintf (str_buf + len, str_size - len, |
594 | "%c", | |
595 | aspath_delimiter_char (seg->type, AS_SEG_START)); | |
fe69a505 | 596 | |
597 | /* write out the ASNs, with their seperators, bar the last one*/ | |
598 | for (i = 0; i < seg->length; i++) | |
599 | { | |
600 | len += snprintf (str_buf + len, str_size - len, "%u", seg->as[i]); | |
601 | ||
602 | if (i < (seg->length - 1)) | |
603 | len += snprintf (str_buf + len, str_size - len, "%c", seperator); | |
604 | } | |
605 | ||
606 | if (seg->type != AS_SEQUENCE) | |
607 | len += snprintf (str_buf + len, str_size - len, "%c", | |
608 | aspath_delimiter_char (seg->type, AS_SEG_END)); | |
609 | if (seg->next) | |
610 | len += snprintf (str_buf + len, str_size - len, " "); | |
611 | ||
612 | seg = seg->next; | |
718e3744 | 613 | } |
fe69a505 | 614 | |
615 | assert (len < str_size); | |
616 | ||
617 | str_buf[len] = '\0'; | |
718e3744 | 618 | |
619 | return str_buf; | |
620 | } | |
621 | ||
fe69a505 | 622 | static void |
623 | aspath_str_update (struct aspath *as) | |
624 | { | |
625 | if (as->str) | |
626 | XFREE (MTYPE_AS_STR, as->str); | |
627 | as->str = aspath_make_str_count (as); | |
628 | } | |
629 | ||
718e3744 | 630 | /* Intern allocated AS path. */ |
631 | struct aspath * | |
632 | aspath_intern (struct aspath *aspath) | |
633 | { | |
634 | struct aspath *find; | |
635 | ||
636 | /* Assert this AS path structure is not interned. */ | |
637 | assert (aspath->refcnt == 0); | |
638 | ||
639 | /* Check AS path hash. */ | |
640 | find = hash_get (ashash, aspath, hash_alloc_intern); | |
641 | ||
642 | if (find != aspath) | |
fe69a505 | 643 | aspath_free (aspath); |
718e3744 | 644 | |
645 | find->refcnt++; | |
646 | ||
647 | if (! find->str) | |
648 | find->str = aspath_make_str_count (find); | |
649 | ||
650 | return find; | |
651 | } | |
652 | ||
653 | /* Duplicate aspath structure. Created same aspath structure but | |
654 | reference count and AS path string is cleared. */ | |
655 | struct aspath * | |
656 | aspath_dup (struct aspath *aspath) | |
657 | { | |
658 | struct aspath *new; | |
659 | ||
fe69a505 | 660 | new = XCALLOC (MTYPE_AS_PATH, sizeof (struct aspath)); |
718e3744 | 661 | |
fe69a505 | 662 | if (aspath->segments) |
663 | new->segments = assegment_dup_all (aspath->segments); | |
718e3744 | 664 | else |
fe69a505 | 665 | new->segments = NULL; |
718e3744 | 666 | |
fe69a505 | 667 | new->str = aspath_make_str_count (aspath); |
718e3744 | 668 | |
669 | return new; | |
670 | } | |
671 | ||
94f2b392 | 672 | static void * |
fe69a505 | 673 | aspath_hash_alloc (void *arg) |
718e3744 | 674 | { |
675 | struct aspath *aspath; | |
676 | ||
0b2aa3a0 | 677 | /* New aspath structure is needed. */ |
fe69a505 | 678 | aspath = aspath_dup (arg); |
679 | ||
718e3744 | 680 | /* Malformed AS path value. */ |
681 | if (! aspath->str) | |
682 | { | |
683 | aspath_free (aspath); | |
684 | return NULL; | |
685 | } | |
686 | ||
687 | return aspath; | |
688 | } | |
689 | ||
fe69a505 | 690 | /* parse as-segment byte stream in struct assegment */ |
ad72740e | 691 | static struct assegment * |
0b2aa3a0 | 692 | assegments_parse (struct stream *s, size_t length, int use32bit) |
fe69a505 | 693 | { |
694 | struct assegment_header segh; | |
695 | struct assegment *seg, *prev = NULL, *head = NULL; | |
696 | size_t bytes = 0; | |
697 | ||
698 | /* empty aspath (ie iBGP or somesuch) */ | |
699 | if (length == 0) | |
700 | return NULL; | |
701 | ||
0b2aa3a0 PJ |
702 | if (BGP_DEBUG (as4, AS4_SEGMENT)) |
703 | zlog_debug ("[AS4SEG] Parse aspath segment: got total byte length %lu", | |
704 | (unsigned long) length); | |
fe69a505 | 705 | /* basic checks */ |
706 | if ( (STREAM_READABLE(s) < length) | |
707 | || (STREAM_READABLE(s) < AS_HEADER_SIZE) | |
0b2aa3a0 | 708 | || (length % AS16_VALUE_SIZE )) |
fe69a505 | 709 | return NULL; |
710 | ||
711 | while ( (STREAM_READABLE(s) > AS_HEADER_SIZE) | |
712 | && (bytes < length)) | |
713 | { | |
714 | int i; | |
0b2aa3a0 | 715 | int seg_size; |
fe69a505 | 716 | |
717 | /* softly softly, get the header first on its own */ | |
718 | segh.type = stream_getc (s); | |
719 | segh.length = stream_getc (s); | |
720 | ||
0b2aa3a0 PJ |
721 | seg_size = ASSEGMENT_SIZE(segh.length, use32bit); |
722 | ||
723 | if (BGP_DEBUG (as4, AS4_SEGMENT)) | |
724 | zlog_debug ("[AS4SEG] Parse aspath segment: got type %d, length %d", | |
725 | segh.type, segh.length); | |
726 | ||
fe69a505 | 727 | /* check it.. */ |
0b2aa3a0 | 728 | if ( ((bytes + seg_size) > length) |
fe69a505 | 729 | /* 1771bis 4.3b: seg length contains one or more */ |
730 | || (segh.length == 0) | |
731 | /* Paranoia in case someone changes type of segment length */ | |
0b2aa3a0 | 732 | || ((sizeof segh.length > 1) && (segh.length > AS_SEGMENT_MAX)) ) |
fe69a505 | 733 | { |
734 | if (head) | |
735 | assegment_free_all (head); | |
736 | return NULL; | |
737 | } | |
738 | ||
739 | /* now its safe to trust lengths */ | |
740 | seg = assegment_new (segh.type, segh.length); | |
741 | ||
742 | if (head) | |
743 | prev->next = seg; | |
744 | else /* it's the first segment */ | |
745 | head = prev = seg; | |
746 | ||
747 | for (i = 0; i < segh.length; i++) | |
0b2aa3a0 PJ |
748 | seg->as[i] = (use32bit) ? stream_getl (s) : stream_getw (s); |
749 | ||
750 | bytes += seg_size; | |
fe69a505 | 751 | |
0b2aa3a0 PJ |
752 | if (BGP_DEBUG (as4, AS4_SEGMENT)) |
753 | zlog_debug ("[AS4SEG] Parse aspath segment: Bytes now: %lu", | |
754 | (unsigned long) bytes); | |
fe69a505 | 755 | |
756 | prev = seg; | |
757 | } | |
758 | ||
759 | return assegment_normalise (head); | |
760 | } | |
761 | ||
718e3744 | 762 | /* AS path parse function. pnt is a pointer to byte stream and length |
763 | is length of byte stream. If there is same AS path in the the AS | |
764 | path hash then return it else make new AS path structure. */ | |
765 | struct aspath * | |
0b2aa3a0 | 766 | aspath_parse (struct stream *s, size_t length, int use32bit) |
718e3744 | 767 | { |
768 | struct aspath as; | |
769 | struct aspath *find; | |
770 | ||
771 | /* If length is odd it's malformed AS path. */ | |
0b2aa3a0 PJ |
772 | /* Nit-picking: if (use32bit == 0) it is malformed if odd, |
773 | * otherwise its malformed when length is larger than 2 and (length-2) | |
774 | * is not dividable by 4. | |
775 | * But... this time we're lazy | |
776 | */ | |
777 | if (length % AS16_VALUE_SIZE ) | |
718e3744 | 778 | return NULL; |
779 | ||
0b2aa3a0 PJ |
780 | memset (&as, 0, sizeof (struct aspath)); |
781 | as.segments = assegments_parse (s, length, use32bit); | |
fe69a505 | 782 | |
718e3744 | 783 | /* If already same aspath exist then return it. */ |
784 | find = hash_get (ashash, &as, aspath_hash_alloc); | |
02335429 | 785 | |
786 | /* aspath_hash_alloc dupes segments too. that probably could be | |
787 | * optimised out. | |
788 | */ | |
789 | assegment_free_all (as.segments); | |
0b2aa3a0 PJ |
790 | if (as.str) |
791 | XFREE (MTYPE_AS_STR, as.str); | |
02335429 | 792 | |
718e3744 | 793 | if (! find) |
794 | return NULL; | |
795 | find->refcnt++; | |
796 | ||
797 | return find; | |
798 | } | |
799 | ||
fe69a505 | 800 | static inline void |
0b2aa3a0 | 801 | assegment_data_put (struct stream *s, as_t *as, int num, int use32bit) |
fe69a505 | 802 | { |
803 | int i; | |
804 | assert (num <= AS_SEGMENT_MAX); | |
805 | ||
806 | for (i = 0; i < num; i++) | |
0b2aa3a0 PJ |
807 | if ( use32bit ) |
808 | stream_putl (s, as[i]); | |
809 | else | |
810 | { | |
811 | if ( as[i] <= BGP_AS_MAX ) | |
812 | stream_putw(s, as[i]); | |
813 | else | |
814 | stream_putw(s, BGP_AS_TRANS); | |
815 | } | |
fe69a505 | 816 | } |
718e3744 | 817 | |
fe69a505 | 818 | static inline size_t |
819 | assegment_header_put (struct stream *s, u_char type, int length) | |
718e3744 | 820 | { |
fe69a505 | 821 | size_t lenp; |
822 | assert (length <= AS_SEGMENT_MAX); | |
823 | stream_putc (s, type); | |
824 | lenp = stream_get_endp (s); | |
825 | stream_putc (s, length); | |
826 | return lenp; | |
827 | } | |
718e3744 | 828 | |
fe69a505 | 829 | /* write aspath data to stream */ |
0b2aa3a0 PJ |
830 | size_t |
831 | aspath_put (struct stream *s, struct aspath *as, int use32bit ) | |
fe69a505 | 832 | { |
833 | struct assegment *seg = as->segments; | |
0b2aa3a0 | 834 | size_t bytes = 0; |
fe69a505 | 835 | |
836 | if (!seg || seg->length == 0) | |
0b2aa3a0 | 837 | return 0; |
fe69a505 | 838 | |
839 | if (seg) | |
718e3744 | 840 | { |
0b2aa3a0 PJ |
841 | /* |
842 | * Hey, what do we do when we have > STREAM_WRITABLE(s) here? | |
843 | * At the moment, we would write out a partial aspath, and our peer | |
844 | * will complain and drop the session :-/ | |
845 | * | |
846 | * The general assumption here is that many things tested will | |
847 | * never happen. And, in real live, up to now, they have not. | |
848 | */ | |
849 | while (seg && (ASSEGMENT_LEN(seg, use32bit) <= STREAM_WRITEABLE(s))) | |
fe69a505 | 850 | { |
0b2aa3a0 | 851 | struct assegment *next = seg->next; |
fe69a505 | 852 | int written = 0; |
0b2aa3a0 | 853 | int asns_packed = 0; |
fe69a505 | 854 | size_t lenp; |
855 | ||
856 | /* Overlength segments have to be split up */ | |
857 | while ( (seg->length - written) > AS_SEGMENT_MAX) | |
858 | { | |
859 | assegment_header_put (s, seg->type, AS_SEGMENT_MAX); | |
0b2aa3a0 | 860 | assegment_data_put (s, seg->as, AS_SEGMENT_MAX, use32bit); |
fe69a505 | 861 | written += AS_SEGMENT_MAX; |
0b2aa3a0 | 862 | bytes += ASSEGMENT_SIZE (written, use32bit); |
fe69a505 | 863 | } |
864 | ||
865 | /* write the final segment, probably is also the first */ | |
866 | lenp = assegment_header_put (s, seg->type, seg->length - written); | |
0b2aa3a0 PJ |
867 | assegment_data_put (s, (seg->as + written), seg->length - written, |
868 | use32bit); | |
fe69a505 | 869 | |
870 | /* Sequence-type segments can be 'packed' together | |
871 | * Case of a segment which was overlength and split up | |
872 | * will be missed here, but that doesn't matter. | |
873 | */ | |
0b2aa3a0 | 874 | while (next && ASSEGMENTS_PACKABLE (seg, next)) |
fe69a505 | 875 | { |
876 | /* NB: We should never normally get here given we | |
877 | * normalise aspath data when parse them. However, better | |
878 | * safe than sorry. We potentially could call | |
879 | * assegment_normalise here instead, but it's cheaper and | |
880 | * easier to do it on the fly here rather than go through | |
881 | * the segment list twice every time we write out | |
882 | * aspath's. | |
883 | */ | |
884 | ||
885 | /* Next segment's data can fit in this one */ | |
0b2aa3a0 | 886 | assegment_data_put (s, next->as, next->length, use32bit); |
fe69a505 | 887 | |
888 | /* update the length of the segment header */ | |
0b2aa3a0 PJ |
889 | stream_putc_at (s, lenp, seg->length - written + next->length); |
890 | asns_packed += next->length; | |
891 | ||
892 | next = next->next; | |
fe69a505 | 893 | } |
0b2aa3a0 PJ |
894 | |
895 | bytes += ASSEGMENT_SIZE (seg->length - written + asns_packed, | |
896 | use32bit); | |
897 | seg = next; | |
fe69a505 | 898 | } |
718e3744 | 899 | } |
0b2aa3a0 | 900 | return bytes; |
fe69a505 | 901 | } |
902 | ||
903 | /* This is for SNMP BGP4PATHATTRASPATHSEGMENT | |
904 | * We have no way to manage the storage, so we use a static stream | |
905 | * wrapper around aspath_put. | |
906 | */ | |
907 | u_char * | |
908 | aspath_snmp_pathseg (struct aspath *as, size_t *varlen) | |
909 | { | |
910 | #define SNMP_PATHSEG_MAX 1024 | |
8fdc32ab | 911 | |
912 | if (!snmp_stream) | |
913 | snmp_stream = stream_new (SNMP_PATHSEG_MAX); | |
718e3744 | 914 | else |
8fdc32ab | 915 | stream_reset (snmp_stream); |
fe69a505 | 916 | |
917 | if (!as) | |
718e3744 | 918 | { |
fe69a505 | 919 | *varlen = 0; |
920 | return NULL; | |
718e3744 | 921 | } |
0b2aa3a0 | 922 | aspath_put (snmp_stream, as, 0); /* use 16 bit for now here */ |
fe69a505 | 923 | |
8fdc32ab | 924 | *varlen = stream_get_endp (snmp_stream); |
925 | return stream_pnt(snmp_stream); | |
718e3744 | 926 | } |
fe69a505 | 927 | |
928 | #define min(A,B) ((A) < (B) ? (A) : (B)) | |
718e3744 | 929 | |
94f2b392 | 930 | static struct assegment * |
718e3744 | 931 | aspath_aggregate_as_set_add (struct aspath *aspath, struct assegment *asset, |
932 | as_t as) | |
933 | { | |
934 | int i; | |
935 | ||
936 | /* If this is first AS set member, create new as-set segment. */ | |
937 | if (asset == NULL) | |
938 | { | |
fe69a505 | 939 | asset = assegment_new (AS_SET, 1); |
940 | if (! aspath->segments) | |
941 | aspath->segments = asset; | |
718e3744 | 942 | else |
fe69a505 | 943 | { |
944 | struct assegment *seg = aspath->segments; | |
945 | while (seg->next) | |
946 | seg = seg->next; | |
947 | seg->next = asset; | |
948 | } | |
718e3744 | 949 | asset->type = AS_SET; |
950 | asset->length = 1; | |
fe69a505 | 951 | asset->as[0] = as; |
718e3744 | 952 | } |
953 | else | |
954 | { | |
718e3744 | 955 | /* Check this AS value already exists or not. */ |
956 | for (i = 0; i < asset->length; i++) | |
fe69a505 | 957 | if (asset->as[i] == as) |
718e3744 | 958 | return asset; |
fe69a505 | 959 | |
718e3744 | 960 | asset->length++; |
fe69a505 | 961 | asset->as = XREALLOC (MTYPE_AS_SEG_DATA, asset->as, |
962 | asset->length * AS_VALUE_SIZE); | |
963 | asset->as[asset->length - 1] = as; | |
718e3744 | 964 | } |
fe69a505 | 965 | |
718e3744 | 966 | |
967 | return asset; | |
968 | } | |
969 | ||
970 | /* Modify as1 using as2 for aggregation. */ | |
971 | struct aspath * | |
972 | aspath_aggregate (struct aspath *as1, struct aspath *as2) | |
973 | { | |
974 | int i; | |
975 | int minlen; | |
976 | int match; | |
fe69a505 | 977 | int from; |
978 | struct assegment *seg1 = as1->segments; | |
979 | struct assegment *seg2 = as2->segments; | |
0b2aa3a0 | 980 | struct aspath *aspath = NULL; |
718e3744 | 981 | struct assegment *asset; |
0b2aa3a0 | 982 | struct assegment *prevseg = NULL; |
718e3744 | 983 | |
984 | match = 0; | |
985 | minlen = 0; | |
986 | aspath = NULL; | |
987 | asset = NULL; | |
718e3744 | 988 | |
989 | /* First of all check common leading sequence. */ | |
fe69a505 | 990 | while (seg1 && seg2) |
0b2aa3a0 | 991 | { |
718e3744 | 992 | /* Check segment type. */ |
993 | if (seg1->type != seg2->type) | |
994 | break; | |
995 | ||
996 | /* Minimum segment length. */ | |
997 | minlen = min (seg1->length, seg2->length); | |
998 | ||
999 | for (match = 0; match < minlen; match++) | |
fe69a505 | 1000 | if (seg1->as[match] != seg2->as[match]) |
718e3744 | 1001 | break; |
1002 | ||
1003 | if (match) | |
1004 | { | |
0b2aa3a0 PJ |
1005 | struct assegment *seg = assegment_new (seg1->type, 0); |
1006 | ||
1007 | seg = assegment_append_asns (seg, seg1->as, match); | |
1008 | ||
718e3744 | 1009 | if (! aspath) |
0b2aa3a0 PJ |
1010 | { |
1011 | aspath = aspath_new (); | |
1012 | aspath->segments = seg; | |
1013 | } | |
1014 | else | |
1015 | prevseg->next = seg; | |
1016 | ||
1017 | prevseg = seg; | |
718e3744 | 1018 | } |
1019 | ||
1020 | if (match != minlen || match != seg1->length | |
1021 | || seg1->length != seg2->length) | |
1022 | break; | |
fe69a505 | 1023 | |
1024 | seg1 = seg1->next; | |
1025 | seg2 = seg2->next; | |
718e3744 | 1026 | } |
1027 | ||
1028 | if (! aspath) | |
1029 | aspath = aspath_new(); | |
1030 | ||
1031 | /* Make as-set using rest of all information. */ | |
fe69a505 | 1032 | from = match; |
1033 | while (seg1) | |
718e3744 | 1034 | { |
fe69a505 | 1035 | for (i = from; i < seg1->length; i++) |
1036 | asset = aspath_aggregate_as_set_add (aspath, asset, seg1->as[i]); | |
1037 | ||
1038 | from = 0; | |
1039 | seg1 = seg1->next; | |
718e3744 | 1040 | } |
1041 | ||
fe69a505 | 1042 | from = match; |
1043 | while (seg2) | |
718e3744 | 1044 | { |
fe69a505 | 1045 | for (i = from; i < seg2->length; i++) |
1046 | asset = aspath_aggregate_as_set_add (aspath, asset, seg2->as[i]); | |
718e3744 | 1047 | |
fe69a505 | 1048 | from = 0; |
1049 | seg2 = seg2->next; | |
718e3744 | 1050 | } |
fe69a505 | 1051 | |
1052 | assegment_normalise (aspath->segments); | |
1053 | aspath_str_update (aspath); | |
718e3744 | 1054 | return aspath; |
1055 | } | |
1056 | ||
1057 | /* When a BGP router receives an UPDATE with an MP_REACH_NLRI | |
1058 | attribute, check the leftmost AS number in the AS_PATH attribute is | |
1059 | or not the peer's AS number. */ | |
1060 | int | |
1061 | aspath_firstas_check (struct aspath *aspath, as_t asno) | |
1062 | { | |
fe69a505 | 1063 | if ( (aspath == NULL) || (aspath->segments == NULL) ) |
718e3744 | 1064 | return 0; |
fe69a505 | 1065 | |
1066 | if (aspath->segments | |
1067 | && (aspath->segments->type == AS_SEQUENCE) | |
1068 | && (aspath->segments->as[0] == asno )) | |
718e3744 | 1069 | return 1; |
1070 | ||
1071 | return 0; | |
1072 | } | |
1073 | ||
1f742f21 | 1074 | /* AS path loop check. If aspath contains asno then return >= 1. */ |
718e3744 | 1075 | int |
1076 | aspath_loop_check (struct aspath *aspath, as_t asno) | |
1077 | { | |
fe69a505 | 1078 | struct assegment *seg; |
718e3744 | 1079 | int count = 0; |
1080 | ||
1f742f21 | 1081 | if ( (aspath == NULL) || (aspath->segments == NULL) ) |
718e3744 | 1082 | return 0; |
fe69a505 | 1083 | |
1084 | seg = aspath->segments; | |
1085 | ||
1086 | while (seg) | |
718e3744 | 1087 | { |
1088 | int i; | |
718e3744 | 1089 | |
fe69a505 | 1090 | for (i = 0; i < seg->length; i++) |
1091 | if (seg->as[i] == asno) | |
718e3744 | 1092 | count++; |
fe69a505 | 1093 | |
1094 | seg = seg->next; | |
718e3744 | 1095 | } |
1096 | return count; | |
1097 | } | |
1098 | ||
1099 | /* When all of AS path is private AS return 1. */ | |
1100 | int | |
1101 | aspath_private_as_check (struct aspath *aspath) | |
1102 | { | |
fe69a505 | 1103 | struct assegment *seg; |
1104 | ||
1105 | if ( !(aspath && aspath->segments) ) | |
718e3744 | 1106 | return 0; |
fe69a505 | 1107 | |
1108 | seg = aspath->segments; | |
718e3744 | 1109 | |
fe69a505 | 1110 | while (seg) |
718e3744 | 1111 | { |
1112 | int i; | |
718e3744 | 1113 | |
fe69a505 | 1114 | for (i = 0; i < seg->length; i++) |
718e3744 | 1115 | { |
fe69a505 | 1116 | if ( (seg->as[i] < BGP_PRIVATE_AS_MIN) |
1117 | || (seg->as[i] > BGP_PRIVATE_AS_MAX) ) | |
718e3744 | 1118 | return 0; |
1119 | } | |
fe69a505 | 1120 | seg = seg->next; |
718e3744 | 1121 | } |
1122 | return 1; | |
1123 | } | |
1124 | ||
1125 | /* Merge as1 to as2. as2 should be uninterned aspath. */ | |
94f2b392 | 1126 | static struct aspath * |
718e3744 | 1127 | aspath_merge (struct aspath *as1, struct aspath *as2) |
1128 | { | |
fe69a505 | 1129 | struct assegment *last, *new; |
718e3744 | 1130 | |
1131 | if (! as1 || ! as2) | |
1132 | return NULL; | |
1133 | ||
fe69a505 | 1134 | last = new = assegment_dup_all (as1->segments); |
1135 | ||
1136 | /* find the last valid segment */ | |
1137 | while (last && last->next) | |
1138 | last = last->next; | |
1139 | ||
1140 | last->next = as2->segments; | |
1141 | as2->segments = new; | |
1142 | aspath_str_update (as2); | |
718e3744 | 1143 | return as2; |
1144 | } | |
1145 | ||
1146 | /* Prepend as1 to as2. as2 should be uninterned aspath. */ | |
1147 | struct aspath * | |
1148 | aspath_prepend (struct aspath *as1, struct aspath *as2) | |
1149 | { | |
fe69a505 | 1150 | struct assegment *seg1; |
1151 | struct assegment *seg2; | |
718e3744 | 1152 | |
1153 | if (! as1 || ! as2) | |
1154 | return NULL; | |
fe69a505 | 1155 | |
1156 | seg1 = as1->segments; | |
1157 | seg2 = as2->segments; | |
1158 | ||
1159 | /* If as2 is empty, only need to dupe as1's chain onto as2 */ | |
718e3744 | 1160 | if (seg2 == NULL) |
1161 | { | |
fe69a505 | 1162 | as2->segments = assegment_dup_all (as1->segments); |
1163 | aspath_str_update (as2); | |
718e3744 | 1164 | return as2; |
1165 | } | |
fe69a505 | 1166 | |
1167 | /* If as1 is empty AS, no prepending to do. */ | |
718e3744 | 1168 | if (seg1 == NULL) |
1169 | return as2; | |
fe69a505 | 1170 | |
1171 | /* find the tail as1's segment chain. */ | |
1172 | while (seg1 && seg1->next) | |
1173 | seg1 = seg1->next; | |
718e3744 | 1174 | |
1175 | /* Compare last segment type of as1 and first segment type of as2. */ | |
1176 | if (seg1->type != seg2->type) | |
1177 | return aspath_merge (as1, as2); | |
1178 | ||
1179 | if (seg1->type == AS_SEQUENCE) | |
1180 | { | |
fe69a505 | 1181 | /* We have two chains of segments, as1->segments and seg2, |
1182 | * and we have to attach them together, merging the attaching | |
1183 | * segments together into one. | |
1184 | * | |
1185 | * 1. dupe as1->segments onto head of as2 | |
1186 | * 2. merge seg2's asns onto last segment of this new chain | |
1187 | * 3. attach chain after seg2 | |
1188 | */ | |
718e3744 | 1189 | |
fe69a505 | 1190 | /* dupe as1 onto as2's head */ |
1191 | seg1 = as2->segments = assegment_dup_all (as1->segments); | |
1192 | ||
1193 | /* refind the tail of as2, reusing seg1 */ | |
1194 | while (seg1 && seg1->next) | |
1195 | seg1 = seg1->next; | |
1196 | ||
1197 | /* merge the old head, seg2, into tail, seg1 */ | |
1198 | seg1 = assegment_append_asns (seg1, seg2->as, seg2->length); | |
1199 | ||
1200 | /* bypass the merged seg2, and attach any chain after it to | |
1201 | * chain descending from as2's head | |
1202 | */ | |
1203 | seg1->next = seg2->next; | |
1204 | ||
1205 | /* seg2 is now referenceless and useless*/ | |
1206 | assegment_free (seg2); | |
1207 | ||
1208 | /* we've now prepended as1's segment chain to as2, merging | |
1209 | * the inbetween AS_SEQUENCE of seg2 in the process | |
1210 | */ | |
1211 | aspath_str_update (as2); | |
718e3744 | 1212 | return as2; |
1213 | } | |
1214 | else | |
1215 | { | |
1216 | /* AS_SET merge code is needed at here. */ | |
1217 | return aspath_merge (as1, as2); | |
1218 | } | |
fe69a505 | 1219 | /* XXX: Ermmm, what if as1 has multiple segments?? */ |
1220 | ||
718e3744 | 1221 | /* Not reached */ |
1222 | } | |
1223 | ||
841f7a57 DO |
1224 | /* Iterate over AS_PATH segments and wipe all occurences of the |
1225 | * listed AS numbers. Hence some segments may lose some or even | |
1226 | * all data on the way, the operation is implemented as a smarter | |
1227 | * version of aspath_dup(), which allocates memory to hold the new | |
1228 | * data, not the original. The new AS path is returned. | |
1229 | */ | |
1230 | struct aspath * | |
1231 | aspath_filter_exclude (struct aspath * source, struct aspath * exclude_list) | |
1232 | { | |
1233 | struct assegment * srcseg, * exclseg, * lastseg; | |
1234 | struct aspath * newpath; | |
1235 | ||
1236 | newpath = aspath_new(); | |
1237 | lastseg = NULL; | |
1238 | ||
1239 | for (srcseg = source->segments; srcseg; srcseg = srcseg->next) | |
1240 | { | |
1241 | unsigned i, y, newlen = 0, done = 0, skip_as; | |
1242 | struct assegment * newseg; | |
1243 | ||
1244 | /* Find out, how much ASns are we going to pick from this segment. | |
1245 | * We can't perform filtering right inline, because the size of | |
1246 | * the new segment isn't known at the moment yet. | |
1247 | */ | |
1248 | for (i = 0; i < srcseg->length; i++) | |
1249 | { | |
1250 | skip_as = 0; | |
1251 | for (exclseg = exclude_list->segments; exclseg && !skip_as; exclseg = exclseg->next) | |
1252 | for (y = 0; y < exclseg->length; y++) | |
1253 | if (srcseg->as[i] == exclseg->as[y]) | |
1254 | { | |
1255 | skip_as = 1; | |
1256 | // There's no sense in testing the rest of exclusion list, bail out. | |
1257 | break; | |
1258 | } | |
1259 | if (!skip_as) | |
1260 | newlen++; | |
1261 | } | |
1262 | /* newlen is now the number of ASns to copy */ | |
1263 | if (!newlen) | |
1264 | continue; | |
1265 | ||
1266 | /* Actual copying. Allocate memory and iterate once more, performing filtering. */ | |
1267 | newseg = assegment_new (srcseg->type, newlen); | |
1268 | for (i = 0; i < srcseg->length; i++) | |
1269 | { | |
1270 | skip_as = 0; | |
1271 | for (exclseg = exclude_list->segments; exclseg && !skip_as; exclseg = exclseg->next) | |
1272 | for (y = 0; y < exclseg->length; y++) | |
1273 | if (srcseg->as[i] == exclseg->as[y]) | |
1274 | { | |
1275 | skip_as = 1; | |
1276 | break; | |
1277 | } | |
1278 | if (skip_as) | |
1279 | continue; | |
1280 | newseg->as[done++] = srcseg->as[i]; | |
1281 | } | |
1282 | /* At his point newlen must be equal to done, and both must be positive. Append | |
1283 | * the filtered segment to the gross result. */ | |
1284 | if (!lastseg) | |
1285 | newpath->segments = newseg; | |
1286 | else | |
1287 | lastseg->next = newseg; | |
1288 | lastseg = newseg; | |
1289 | } | |
1290 | aspath_str_update (newpath); | |
1291 | /* We are happy returning even an empty AS_PATH, because the administrator | |
1292 | * might expect this very behaviour. There's a mean to avoid this, if necessary, | |
1293 | * by having a match rule against certain AS_PATH regexps in the route-map index. | |
1294 | */ | |
1295 | aspath_free (source); | |
1296 | return newpath; | |
1297 | } | |
1298 | ||
718e3744 | 1299 | /* Add specified AS to the leftmost of aspath. */ |
1300 | static struct aspath * | |
1301 | aspath_add_one_as (struct aspath *aspath, as_t asno, u_char type) | |
1302 | { | |
fe69a505 | 1303 | struct assegment *assegment = aspath->segments; |
718e3744 | 1304 | |
1305 | /* In case of empty aspath. */ | |
1306 | if (assegment == NULL || assegment->length == 0) | |
1307 | { | |
fe69a505 | 1308 | aspath->segments = assegment_new (type, 1); |
1309 | aspath->segments->as[0] = asno; | |
1310 | ||
718e3744 | 1311 | if (assegment) |
fe69a505 | 1312 | assegment_free (assegment); |
718e3744 | 1313 | |
1314 | return aspath; | |
1315 | } | |
1316 | ||
1317 | if (assegment->type == type) | |
fe69a505 | 1318 | aspath->segments = assegment_prepend_asns (aspath->segments, asno, 1); |
1319 | else | |
718e3744 | 1320 | { |
fe69a505 | 1321 | /* create new segment |
1322 | * push it onto head of aspath's segment chain | |
1323 | */ | |
718e3744 | 1324 | struct assegment *newsegment; |
fe69a505 | 1325 | |
1326 | newsegment = assegment_new (type, 1); | |
1327 | newsegment->as[0] = asno; | |
1328 | ||
1329 | newsegment->next = assegment; | |
1330 | aspath->segments = newsegment; | |
718e3744 | 1331 | } |
1332 | ||
1333 | return aspath; | |
1334 | } | |
1335 | ||
1336 | /* Add specified AS to the leftmost of aspath. */ | |
1337 | struct aspath * | |
1338 | aspath_add_seq (struct aspath *aspath, as_t asno) | |
1339 | { | |
1340 | return aspath_add_one_as (aspath, asno, AS_SEQUENCE); | |
1341 | } | |
1342 | ||
1343 | /* Compare leftmost AS value for MED check. If as1's leftmost AS and | |
1344 | as2's leftmost AS is same return 1. */ | |
1345 | int | |
ffe11cfb | 1346 | aspath_cmp_left (const struct aspath *aspath1, const struct aspath *aspath2) |
718e3744 | 1347 | { |
ffe11cfb SH |
1348 | const struct assegment *seg1 = NULL; |
1349 | const struct assegment *seg2 = NULL; | |
718e3744 | 1350 | |
fe69a505 | 1351 | if (!(aspath1 && aspath2)) |
1352 | return 0; | |
718e3744 | 1353 | |
fe69a505 | 1354 | seg1 = aspath1->segments; |
1355 | seg2 = aspath2->segments; | |
718e3744 | 1356 | |
fe69a505 | 1357 | /* find first non-confed segments for each */ |
1358 | while (seg1 && ((seg1->type == AS_CONFED_SEQUENCE) | |
1359 | || (seg1->type == AS_CONFED_SET))) | |
1360 | seg1 = seg1->next; | |
718e3744 | 1361 | |
fe69a505 | 1362 | while (seg2 && ((seg2->type == AS_CONFED_SEQUENCE) |
1363 | || (seg2->type == AS_CONFED_SET))) | |
1364 | seg2 = seg2->next; | |
718e3744 | 1365 | |
fe69a505 | 1366 | /* Check as1's */ |
1367 | if (!(seg1 && seg2 | |
1368 | && (seg1->type == AS_SEQUENCE) && (seg2->type == AS_SEQUENCE))) | |
1369 | return 0; | |
1370 | ||
1371 | if (seg1->as[0] == seg2->as[0]) | |
718e3744 | 1372 | return 1; |
1373 | ||
1374 | return 0; | |
1375 | } | |
1376 | ||
0b2aa3a0 PJ |
1377 | /* Truncate an aspath after a number of hops, and put the hops remaining |
1378 | * at the front of another aspath. Needed for AS4 compat. | |
1379 | * | |
1380 | * Returned aspath is a /new/ aspath, which should either by free'd or | |
1381 | * interned by the caller, as desired. | |
1382 | */ | |
1383 | struct aspath * | |
1384 | aspath_reconcile_as4 ( struct aspath *aspath, struct aspath *as4path) | |
1385 | { | |
1386 | struct assegment *seg, *newseg, *prevseg = NULL; | |
1387 | struct aspath *newpath = NULL, *mergedpath; | |
1388 | int hops, cpasns = 0; | |
1389 | ||
1390 | if (!aspath) | |
1391 | return NULL; | |
1392 | ||
1393 | seg = aspath->segments; | |
1394 | ||
1395 | /* CONFEDs should get reconciled too.. */ | |
1396 | hops = (aspath_count_hops (aspath) + aspath_count_confeds (aspath)) | |
1397 | - aspath_count_hops (as4path); | |
1398 | ||
1399 | if (hops < 0) | |
1400 | { | |
1401 | if (BGP_DEBUG (as4, AS4)) | |
1402 | zlog_warn ("[AS4] Fewer hops in AS_PATH than NEW_AS_PATH"); | |
1403 | /* Something's gone wrong. The RFC says we should now ignore AS4_PATH, | |
1404 | * which is daft behaviour - it contains vital loop-detection | |
1405 | * information which must have been removed from AS_PATH. | |
1406 | */ | |
1407 | hops = aspath_count_hops (aspath); | |
1408 | } | |
1409 | ||
1410 | if (!hops) | |
1411 | return aspath_dup (as4path); | |
1412 | ||
1413 | if ( BGP_DEBUG(as4, AS4)) | |
1414 | zlog_debug("[AS4] got AS_PATH %s and AS4_PATH %s synthesizing now", | |
1415 | aspath->str, as4path->str); | |
1416 | ||
1417 | while (seg && hops > 0) | |
1418 | { | |
1419 | switch (seg->type) | |
1420 | { | |
1421 | case AS_SET: | |
1422 | case AS_CONFED_SET: | |
1423 | hops--; | |
1424 | cpasns = seg->length; | |
1425 | break; | |
1426 | case AS_CONFED_SEQUENCE: | |
1427 | /* Should never split a confed-sequence, if hop-count | |
1428 | * suggests we must then something's gone wrong somewhere. | |
1429 | * | |
1430 | * Most important goal is to preserve AS_PATHs prime function | |
1431 | * as loop-detector, so we fudge the numbers so that the entire | |
1432 | * confed-sequence is merged in. | |
1433 | */ | |
1434 | if (hops < seg->length) | |
1435 | { | |
1436 | if (BGP_DEBUG (as4, AS4)) | |
1437 | zlog_debug ("[AS4] AS4PATHmangle: AS_CONFED_SEQUENCE falls" | |
1438 | " across 2/4 ASN boundary somewhere, broken.."); | |
1439 | hops = seg->length; | |
1440 | } | |
1441 | case AS_SEQUENCE: | |
1442 | cpasns = MIN(seg->length, hops); | |
1443 | hops -= seg->length; | |
1444 | } | |
1445 | ||
1446 | assert (cpasns <= seg->length); | |
1447 | ||
1448 | newseg = assegment_new (seg->type, 0); | |
1449 | newseg = assegment_append_asns (newseg, seg->as, cpasns); | |
1450 | ||
1451 | if (!newpath) | |
1452 | { | |
1453 | newpath = aspath_new (); | |
1454 | newpath->segments = newseg; | |
1455 | } | |
1456 | else | |
1457 | prevseg->next = newseg; | |
1458 | ||
1459 | prevseg = newseg; | |
1460 | seg = seg->next; | |
1461 | } | |
1462 | ||
1463 | /* We may be able to join some segments here, and we must | |
1464 | * do this because... we want normalised aspaths in out hash | |
1465 | * and we do not want to stumble in aspath_put. | |
1466 | */ | |
1467 | mergedpath = aspath_merge (newpath, aspath_dup(as4path)); | |
1468 | aspath_free (newpath); | |
1469 | mergedpath->segments = assegment_normalise (mergedpath->segments); | |
1470 | aspath_str_update (mergedpath); | |
1471 | ||
1472 | if ( BGP_DEBUG(as4, AS4)) | |
1473 | zlog_debug ("[AS4] result of synthesizing is %s", | |
1474 | mergedpath->str); | |
1475 | ||
1476 | return mergedpath; | |
1477 | } | |
1478 | ||
718e3744 | 1479 | /* Compare leftmost AS value for MED check. If as1's leftmost AS and |
1480 | as2's leftmost AS is same return 1. (confederation as-path | |
1481 | only). */ | |
1482 | int | |
ffe11cfb | 1483 | aspath_cmp_left_confed (const struct aspath *aspath1, const struct aspath *aspath2) |
718e3744 | 1484 | { |
fe69a505 | 1485 | if (! (aspath1 && aspath2) ) |
718e3744 | 1486 | return 0; |
fe69a505 | 1487 | |
ad72740e | 1488 | if ( !(aspath1->segments && aspath2->segments) ) |
1489 | return 0; | |
1490 | ||
fe69a505 | 1491 | if ( (aspath1->segments->type != AS_CONFED_SEQUENCE) |
1492 | || (aspath2->segments->type != AS_CONFED_SEQUENCE) ) | |
718e3744 | 1493 | return 0; |
fe69a505 | 1494 | |
1495 | if (aspath1->segments->as[0] == aspath2->segments->as[0]) | |
718e3744 | 1496 | return 1; |
1497 | ||
1498 | return 0; | |
1499 | } | |
1500 | ||
fe69a505 | 1501 | /* Delete all leading AS_CONFED_SEQUENCE/SET segments from aspath. |
1502 | * See RFC3065, 6.1 c1 */ | |
718e3744 | 1503 | struct aspath * |
1504 | aspath_delete_confed_seq (struct aspath *aspath) | |
1505 | { | |
fe69a505 | 1506 | struct assegment *seg; |
718e3744 | 1507 | |
fe69a505 | 1508 | if (!(aspath && aspath->segments)) |
718e3744 | 1509 | return aspath; |
1510 | ||
fe69a505 | 1511 | seg = aspath->segments; |
1512 | ||
1513 | /* "if the first path segment of the AS_PATH is | |
1514 | * of type AS_CONFED_SEQUENCE," | |
1515 | */ | |
1516 | if (aspath->segments->type != AS_CONFED_SEQUENCE) | |
1517 | return aspath; | |
718e3744 | 1518 | |
fe69a505 | 1519 | /* "... that segment and any immediately following segments |
1520 | * of the type AS_CONFED_SET or AS_CONFED_SEQUENCE are removed | |
1521 | * from the AS_PATH attribute," | |
1522 | */ | |
1523 | while (seg && | |
1524 | (seg->type == AS_CONFED_SEQUENCE || seg->type == AS_CONFED_SET)) | |
718e3744 | 1525 | { |
fe69a505 | 1526 | aspath->segments = seg->next; |
1527 | assegment_free (seg); | |
1528 | seg = aspath->segments; | |
718e3744 | 1529 | } |
fe69a505 | 1530 | aspath_str_update (aspath); |
718e3744 | 1531 | return aspath; |
1532 | } | |
1533 | ||
1534 | /* Add new AS number to the leftmost part of the aspath as | |
1535 | AS_CONFED_SEQUENCE. */ | |
1536 | struct aspath* | |
1537 | aspath_add_confed_seq (struct aspath *aspath, as_t asno) | |
1538 | { | |
1539 | return aspath_add_one_as (aspath, asno, AS_CONFED_SEQUENCE); | |
1540 | } | |
1541 | ||
1542 | /* Add new as value to as path structure. */ | |
94f2b392 | 1543 | static void |
718e3744 | 1544 | aspath_as_add (struct aspath *as, as_t asno) |
1545 | { | |
fe69a505 | 1546 | struct assegment *seg = as->segments; |
718e3744 | 1547 | |
fe69a505 | 1548 | if (!seg) |
1549 | return; | |
1550 | ||
93c1749c AS |
1551 | /* Last segment search procedure. */ |
1552 | while (seg->next) | |
1553 | seg = seg->next; | |
1554 | ||
fe69a505 | 1555 | assegment_append_asns (seg, &asno, 1); |
718e3744 | 1556 | } |
1557 | ||
1558 | /* Add new as segment to the as path. */ | |
94f2b392 | 1559 | static void |
718e3744 | 1560 | aspath_segment_add (struct aspath *as, int type) |
1561 | { | |
fe69a505 | 1562 | struct assegment *seg = as->segments; |
1563 | struct assegment *new = assegment_new (type, 0); | |
718e3744 | 1564 | |
93c1749c AS |
1565 | if (seg) |
1566 | { | |
1567 | while (seg->next) | |
1568 | seg = seg->next; | |
1569 | seg->next = new; | |
1570 | } | |
718e3744 | 1571 | else |
93c1749c | 1572 | as->segments = new; |
718e3744 | 1573 | } |
1574 | ||
1575 | struct aspath * | |
94f2b392 | 1576 | aspath_empty (void) |
718e3744 | 1577 | { |
0b2aa3a0 | 1578 | return aspath_parse (NULL, 0, 1); /* 32Bit ;-) */ |
718e3744 | 1579 | } |
1580 | ||
1581 | struct aspath * | |
94f2b392 | 1582 | aspath_empty_get (void) |
718e3744 | 1583 | { |
1584 | struct aspath *aspath; | |
1585 | ||
1586 | aspath = aspath_new (); | |
1587 | aspath->str = aspath_make_str_count (aspath); | |
1588 | return aspath; | |
1589 | } | |
1590 | ||
1591 | unsigned long | |
fe69a505 | 1592 | aspath_count (void) |
718e3744 | 1593 | { |
1594 | return ashash->count; | |
1595 | } | |
1596 | \f | |
1597 | /* | |
1598 | Theoretically, one as path can have: | |
1599 | ||
1600 | One BGP packet size should be less than 4096. | |
1601 | One BGP attribute size should be less than 4096 - BGP header size. | |
1602 | One BGP aspath size should be less than 4096 - BGP header size - | |
1603 | BGP mandantry attribute size. | |
1604 | */ | |
1605 | ||
1606 | /* AS path string lexical token enum. */ | |
1607 | enum as_token | |
1608 | { | |
1609 | as_token_asval, | |
1610 | as_token_set_start, | |
1611 | as_token_set_end, | |
fe69a505 | 1612 | as_token_confed_seq_start, |
1613 | as_token_confed_seq_end, | |
1614 | as_token_confed_set_start, | |
1615 | as_token_confed_set_end, | |
718e3744 | 1616 | as_token_unknown |
1617 | }; | |
1618 | ||
1619 | /* Return next token and point for string parse. */ | |
94f2b392 | 1620 | static const char * |
0b2aa3a0 | 1621 | aspath_gettoken (const char *buf, enum as_token *token, u_long *asno) |
718e3744 | 1622 | { |
fd79ac91 | 1623 | const char *p = buf; |
718e3744 | 1624 | |
fe69a505 | 1625 | /* Skip seperators (space for sequences, ',' for sets). */ |
1626 | while (isspace ((int) *p) || *p == ',') | |
718e3744 | 1627 | p++; |
1628 | ||
1629 | /* Check the end of the string and type specify characters | |
1630 | (e.g. {}()). */ | |
1631 | switch (*p) | |
1632 | { | |
1633 | case '\0': | |
1634 | return NULL; | |
718e3744 | 1635 | case '{': |
1636 | *token = as_token_set_start; | |
1637 | p++; | |
1638 | return p; | |
718e3744 | 1639 | case '}': |
1640 | *token = as_token_set_end; | |
1641 | p++; | |
1642 | return p; | |
718e3744 | 1643 | case '(': |
fe69a505 | 1644 | *token = as_token_confed_seq_start; |
718e3744 | 1645 | p++; |
1646 | return p; | |
718e3744 | 1647 | case ')': |
fe69a505 | 1648 | *token = as_token_confed_seq_end; |
1649 | p++; | |
1650 | return p; | |
fe69a505 | 1651 | case '[': |
1652 | *token = as_token_confed_set_start; | |
1653 | p++; | |
1654 | return p; | |
fe69a505 | 1655 | case ']': |
1656 | *token = as_token_confed_set_end; | |
718e3744 | 1657 | p++; |
1658 | return p; | |
718e3744 | 1659 | } |
1660 | ||
1661 | /* Check actual AS value. */ | |
1662 | if (isdigit ((int) *p)) | |
1663 | { | |
10819ece | 1664 | as_t asval; |
0b2aa3a0 | 1665 | |
718e3744 | 1666 | *token = as_token_asval; |
1667 | asval = (*p - '0'); | |
1668 | p++; | |
0b2aa3a0 | 1669 | |
718e3744 | 1670 | while (isdigit ((int) *p)) |
0b2aa3a0 PJ |
1671 | { |
1672 | asval *= 10; | |
1673 | asval += (*p - '0'); | |
1674 | p++; | |
1675 | } | |
718e3744 | 1676 | *asno = asval; |
1677 | return p; | |
1678 | } | |
1679 | ||
1680 | /* There is no match then return unknown token. */ | |
1681 | *token = as_token_unknown; | |
1682 | return p++; | |
1683 | } | |
1684 | ||
1685 | struct aspath * | |
fd79ac91 | 1686 | aspath_str2aspath (const char *str) |
718e3744 | 1687 | { |
3fff6ffc | 1688 | enum as_token token = as_token_unknown; |
718e3744 | 1689 | u_short as_type; |
0b2aa3a0 | 1690 | u_long asno = 0; |
718e3744 | 1691 | struct aspath *aspath; |
1692 | int needtype; | |
1693 | ||
1694 | aspath = aspath_new (); | |
1695 | ||
1696 | /* We start default type as AS_SEQUENCE. */ | |
1697 | as_type = AS_SEQUENCE; | |
1698 | needtype = 1; | |
1699 | ||
1700 | while ((str = aspath_gettoken (str, &token, &asno)) != NULL) | |
1701 | { | |
1702 | switch (token) | |
1703 | { | |
1704 | case as_token_asval: | |
1705 | if (needtype) | |
1706 | { | |
1707 | aspath_segment_add (aspath, as_type); | |
1708 | needtype = 0; | |
1709 | } | |
1710 | aspath_as_add (aspath, asno); | |
1711 | break; | |
1712 | case as_token_set_start: | |
1713 | as_type = AS_SET; | |
1714 | aspath_segment_add (aspath, as_type); | |
1715 | needtype = 0; | |
1716 | break; | |
1717 | case as_token_set_end: | |
1718 | as_type = AS_SEQUENCE; | |
1719 | needtype = 1; | |
1720 | break; | |
fe69a505 | 1721 | case as_token_confed_seq_start: |
718e3744 | 1722 | as_type = AS_CONFED_SEQUENCE; |
1723 | aspath_segment_add (aspath, as_type); | |
1724 | needtype = 0; | |
1725 | break; | |
fe69a505 | 1726 | case as_token_confed_seq_end: |
1727 | as_type = AS_SEQUENCE; | |
1728 | needtype = 1; | |
1729 | break; | |
1730 | case as_token_confed_set_start: | |
1731 | as_type = AS_CONFED_SET; | |
1732 | aspath_segment_add (aspath, as_type); | |
1733 | needtype = 0; | |
1734 | break; | |
1735 | case as_token_confed_set_end: | |
718e3744 | 1736 | as_type = AS_SEQUENCE; |
1737 | needtype = 1; | |
1738 | break; | |
1739 | case as_token_unknown: | |
1740 | default: | |
fe69a505 | 1741 | aspath_free (aspath); |
718e3744 | 1742 | return NULL; |
718e3744 | 1743 | } |
1744 | } | |
1745 | ||
1746 | aspath->str = aspath_make_str_count (aspath); | |
1747 | ||
1748 | return aspath; | |
1749 | } | |
1750 | \f | |
1751 | /* Make hash value by raw aspath data. */ | |
1752 | unsigned int | |
923de654 | 1753 | aspath_key_make (void *p) |
718e3744 | 1754 | { |
923de654 | 1755 | struct aspath * aspath = (struct aspath *) p; |
718e3744 | 1756 | unsigned int key = 0; |
718e3744 | 1757 | |
0b2aa3a0 PJ |
1758 | if (!aspath->str) |
1759 | aspath_str_update (aspath); | |
1760 | ||
1761 | key = jhash (aspath->str, strlen(aspath->str), 2334325); | |
718e3744 | 1762 | |
1763 | return key; | |
1764 | } | |
1765 | ||
1766 | /* If two aspath have same value then return 1 else return 0 */ | |
94f2b392 | 1767 | static int |
ffe11cfb | 1768 | aspath_cmp (const void *arg1, const void *arg2) |
718e3744 | 1769 | { |
aea339f7 DO |
1770 | const struct assegment *seg1 = ((const struct aspath *)arg1)->segments; |
1771 | const struct assegment *seg2 = ((const struct aspath *)arg2)->segments; | |
fe69a505 | 1772 | |
1773 | while (seg1 || seg2) | |
1774 | { | |
1775 | int i; | |
1776 | if ((!seg1 && seg2) || (seg1 && !seg2)) | |
1777 | return 0; | |
1778 | if (seg1->type != seg2->type) | |
1779 | return 0; | |
1780 | if (seg1->length != seg2->length) | |
1781 | return 0; | |
1782 | for (i = 0; i < seg1->length; i++) | |
1783 | if (seg1->as[i] != seg2->as[i]) | |
1784 | return 0; | |
1785 | seg1 = seg1->next; | |
1786 | seg2 = seg2->next; | |
1787 | } | |
1788 | return 1; | |
718e3744 | 1789 | } |
1790 | ||
1791 | /* AS path hash initialize. */ | |
1792 | void | |
94f2b392 | 1793 | aspath_init (void) |
718e3744 | 1794 | { |
1795 | ashash = hash_create_size (32767, aspath_key_make, aspath_cmp); | |
1796 | } | |
8fdc32ab | 1797 | |
1798 | void | |
1799 | aspath_finish (void) | |
1800 | { | |
1801 | hash_free (ashash); | |
1802 | ||
1803 | if (snmp_stream) | |
1804 | stream_free (snmp_stream); | |
1805 | } | |
718e3744 | 1806 | \f |
1807 | /* return and as path value */ | |
1808 | const char * | |
1809 | aspath_print (struct aspath *as) | |
1810 | { | |
fe69a505 | 1811 | return (as ? as->str : NULL); |
718e3744 | 1812 | } |
1813 | ||
1814 | /* Printing functions */ | |
841f7a57 DO |
1815 | /* Feed the AS_PATH to the vty; the suffix string follows it only in case |
1816 | * AS_PATH wasn't empty. | |
1817 | */ | |
718e3744 | 1818 | void |
841f7a57 | 1819 | aspath_print_vty (struct vty *vty, const char *format, struct aspath *as, const char * suffix) |
718e3744 | 1820 | { |
b2518c1e PJ |
1821 | assert (format); |
1822 | vty_out (vty, format, as->str); | |
841f7a57 DO |
1823 | if (strlen (as->str) && strlen (suffix)) |
1824 | vty_out (vty, "%s", suffix); | |
718e3744 | 1825 | } |
1826 | ||
94f2b392 | 1827 | static void |
718e3744 | 1828 | aspath_show_all_iterator (struct hash_backet *backet, struct vty *vty) |
1829 | { | |
1830 | struct aspath *as; | |
1831 | ||
1832 | as = (struct aspath *) backet->data; | |
1833 | ||
efa9f830 | 1834 | vty_out (vty, "[%p:%u] (%ld) ", backet, backet->key, as->refcnt); |
718e3744 | 1835 | vty_out (vty, "%s%s", as->str, VTY_NEWLINE); |
1836 | } | |
1837 | ||
1838 | /* Print all aspath and hash information. This function is used from | |
1839 | `show ip bgp paths' command. */ | |
1840 | void | |
1841 | aspath_print_all_vty (struct vty *vty) | |
1842 | { | |
1843 | hash_iterate (ashash, | |
1844 | (void (*) (struct hash_backet *, void *)) | |
1845 | aspath_show_all_iterator, | |
1846 | vty); | |
1847 | } |