1 /* AS path management routines.
2 * Copyright (C) 1996, 97, 98, 99 Kunihiro Ishiguro
3 * Copyright (C) 2005 Sun Microsystems, Inc.
5 * This file is part of GNU Zebra.
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
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.
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
34 #include "bgpd/bgpd.h"
35 #include "bgpd/bgp_aspath.h"
36 #include "bgpd/bgp_debug.h"
37 #include "bgpd/bgp_attr.h"
38 #include "bgpd/bgp_errors.h"
40 /* Attr. Flags and Attr. Type Code. */
41 #define AS_HEADER_SIZE 2
43 /* Now FOUR octets are used for AS value. */
44 #define AS_VALUE_SIZE sizeof(as_t)
45 /* This is the old one */
46 #define AS16_VALUE_SIZE sizeof(as16_t)
48 /* Maximum protocol segment length value */
49 #define AS_SEGMENT_MAX 255
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.
57 * aspath_put returns bytes written, the only definitive record of
58 * size of wire-format attribute..
61 /* Calculated size in bytes of ASN segment data to hold N ASN's */
62 #define ASSEGMENT_DATA_SIZE(N, S) \
63 ((N) * ((S) ? AS_VALUE_SIZE : AS16_VALUE_SIZE))
65 /* Calculated size of segment struct to hold N ASN's */
66 #define ASSEGMENT_SIZE(N,S) (AS_HEADER_SIZE + ASSEGMENT_DATA_SIZE (N,S))
68 /* AS segment octet length. */
69 #define ASSEGMENT_LEN(X,S) ASSEGMENT_SIZE((X)->length,S)
71 /* AS_SEQUENCE segments can be packed together */
72 /* Can the types of X and Y be considered for packing? */
73 #define ASSEGMENT_TYPES_PACKABLE(X, Y) \
74 (((X)->type == (Y)->type) && ((X)->type == AS_SEQUENCE))
75 /* Types and length of X,Y suitable for packing? */
76 #define ASSEGMENTS_PACKABLE(X, Y) \
77 (ASSEGMENT_TYPES_PACKABLE((X), (Y)) \
78 && (((X)->length + (Y)->length) <= AS_SEGMENT_MAX))
80 /* As segment header - the on-wire representation
81 * NOT the internal representation!
83 struct assegment_header
{
88 /* Hash for aspath. This is the top level structure of AS path. */
89 static struct hash
*ashash
;
91 /* Stream for SNMP. See aspath_snmp_pathseg */
92 static struct stream
*snmp_stream
;
94 /* Callers are required to initialize the memory */
95 static as_t
*assegment_data_new(int num
)
97 return (XMALLOC(MTYPE_AS_SEG_DATA
, ASSEGMENT_DATA_SIZE(num
, 1)));
100 static void assegment_data_free(as_t
*asdata
)
102 XFREE(MTYPE_AS_SEG_DATA
, asdata
);
105 const char *const aspath_segment_type_str
[] = {
106 "as-invalid", "as-set", "as-sequence", "as-confed-sequence",
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
115 static struct assegment
*assegment_new(uint8_t type
, unsigned short length
)
117 struct assegment
*new;
119 new = XCALLOC(MTYPE_AS_SEG
, sizeof(struct assegment
));
122 new->as
= assegment_data_new(length
);
124 new->length
= length
;
130 static void assegment_free(struct assegment
*seg
)
135 assegment_data_free(seg
->as
);
136 memset(seg
, 0xfe, sizeof(struct assegment
));
137 XFREE(MTYPE_AS_SEG
, seg
);
142 /* free entire chain of segments */
143 static void assegment_free_all(struct assegment
*seg
)
145 struct assegment
*prev
;
150 assegment_free(prev
);
154 /* Duplicate just the given assegment and its data */
155 static struct assegment
*assegment_dup(struct assegment
*seg
)
157 struct assegment
*new;
159 new = assegment_new(seg
->type
, seg
->length
);
160 memcpy(new->as
, seg
->as
, ASSEGMENT_DATA_SIZE(new->length
, 1));
165 /* Duplicate entire chain of assegments, return the head */
166 static struct assegment
*assegment_dup_all(struct assegment
*seg
)
168 struct assegment
*new = NULL
;
169 struct assegment
*head
= NULL
;
173 new->next
= assegment_dup(seg
);
176 head
= new = assegment_dup(seg
);
183 /* prepend the as number to given segment, given num of times */
184 static struct assegment
*assegment_prepend_asns(struct assegment
*seg
,
193 if (num
>= AS_SEGMENT_MAX
)
194 return seg
; /* we don't do huge prepends */
196 newas
= assegment_data_new(seg
->length
+ num
);
200 for (i
= 0; i
< num
; i
++)
203 memcpy(newas
+ num
, seg
->as
, ASSEGMENT_DATA_SIZE(seg
->length
, 1));
204 assegment_data_free(seg
->as
);
211 /* append given array of as numbers to the segment */
212 static struct assegment
*assegment_append_asns(struct assegment
*seg
,
213 as_t
*asnos
, int num
)
220 newas
= XREALLOC(MTYPE_AS_SEG_DATA
, seg
->as
,
221 ASSEGMENT_DATA_SIZE(seg
->length
+ num
, 1));
224 memcpy(seg
->as
+ seg
->length
, asnos
,
225 ASSEGMENT_DATA_SIZE(num
, 1));
230 static int int_cmp(const void *p1
, const void *p2
)
232 const as_t
*as1
= p1
;
233 const as_t
*as2
= p2
;
235 return (*as1
== *as2
) ? 0 : ((*as1
> *as2
) ? 1 : -1);
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..
244 static struct assegment
*assegment_normalise(struct assegment
*head
)
246 struct assegment
*seg
= head
, *pin
;
247 struct assegment
*tmp
;
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 ;)
259 if (seg
->type
== AS_SET
|| seg
->type
== AS_CONFED_SET
) {
263 qsort(seg
->as
, seg
->length
, sizeof(as_t
), int_cmp
);
266 for (i
= 1; i
< seg
->length
; i
++) {
267 if (seg
->as
[tail
] == seg
->as
[i
])
272 seg
->as
[tail
] = seg
->as
[i
];
274 /* seg->length can be 0.. */
276 seg
->length
= tail
+ 1;
279 /* read ahead from the current, pinned segment while the
281 * are packable/mergeable. Append all following packable
283 * to the segment we have pinned and remove these appended
286 while (pin
->next
&& ASSEGMENT_TYPES_PACKABLE(pin
, pin
->next
)) {
290 /* append the next sequence to the pinned sequence */
291 pin
= assegment_append_asns(pin
, seg
->as
, seg
->length
);
293 /* bypass the next sequence */
294 pin
->next
= seg
->next
;
296 /* get rid of the now referenceless segment */
305 static struct aspath
*aspath_new(void)
307 return XCALLOC(MTYPE_AS_PATH
, sizeof(struct aspath
));
310 /* Free AS path structure. */
311 void aspath_free(struct aspath
*aspath
)
315 if (aspath
->segments
)
316 assegment_free_all(aspath
->segments
);
317 XFREE(MTYPE_AS_STR
, aspath
->str
);
320 json_object_free(aspath
->json
);
324 XFREE(MTYPE_AS_PATH
, aspath
);
327 /* Unintern aspath from AS path bucket. */
328 void aspath_unintern(struct aspath
**aspath
)
341 if (asp
->refcnt
== 0) {
342 /* This aspath must exist in aspath hash table. */
343 ret
= hash_release(ashash
, asp
);
350 /* Return the start or end delimiters for a particular Segment type */
351 #define AS_SEG_START 0
353 static char aspath_delimiter_char(uint8_t type
, uint8_t which
)
360 } aspath_delim_char
[] = {{AS_SET
, '{', '}'},
361 {AS_CONFED_SET
, '[', ']'},
362 {AS_CONFED_SEQUENCE
, '(', ')'},
365 for (i
= 0; aspath_delim_char
[i
].type
!= 0; i
++) {
366 if (aspath_delim_char
[i
].type
== type
) {
367 if (which
== AS_SEG_START
)
368 return aspath_delim_char
[i
].start
;
369 else if (which
== AS_SEG_END
)
370 return aspath_delim_char
[i
].end
;
376 /* countup asns from this segment and index onward */
377 static int assegment_count_asns(struct assegment
*seg
, int from
)
382 count
+= seg
->length
;
384 count
+= (seg
->length
- from
);
392 unsigned int aspath_count_confeds(struct aspath
*aspath
)
395 struct assegment
*seg
= aspath
->segments
;
398 if (seg
->type
== AS_CONFED_SEQUENCE
)
399 count
+= seg
->length
;
400 else if (seg
->type
== AS_CONFED_SET
)
408 unsigned int aspath_count_hops(const struct aspath
*aspath
)
411 struct assegment
*seg
= aspath
->segments
;
414 if (seg
->type
== AS_SEQUENCE
)
415 count
+= seg
->length
;
416 else if (seg
->type
== AS_SET
)
424 /* Check if aspath has AS_SET or AS_CONFED_SET */
425 bool aspath_check_as_sets(struct aspath
*aspath
)
427 struct assegment
*seg
= aspath
->segments
;
430 if (seg
->type
== AS_SET
|| seg
->type
== AS_CONFED_SET
)
437 /* Check if aspath has BGP_AS_ZERO */
438 bool aspath_check_as_zero(struct aspath
*aspath
)
440 struct assegment
*seg
= aspath
->segments
;
444 for (i
= 0; i
< seg
->length
; i
++)
445 if (seg
->as
[i
] == BGP_AS_ZERO
)
453 /* Estimate size aspath /might/ take if encoded into an
456 * This is a quick estimate, not definitive! aspath_put()
457 * may return a different number!!
459 unsigned int aspath_size(struct aspath
*aspath
)
462 struct assegment
*seg
= aspath
->segments
;
465 size
+= ASSEGMENT_SIZE(seg
->length
, 1);
471 /* Return highest public ASN in path */
472 as_t
aspath_highest(struct aspath
*aspath
)
474 struct assegment
*seg
= aspath
->segments
;
479 for (i
= 0; i
< seg
->length
; i
++)
480 if (seg
->as
[i
] > highest
481 && !BGP_AS_IS_PRIVATE(seg
->as
[i
]))
482 highest
= seg
->as
[i
];
488 /* Return the left-most ASN in path */
489 as_t
aspath_leftmost(struct aspath
*aspath
)
491 struct assegment
*seg
= aspath
->segments
;
494 if (seg
&& seg
->length
&& seg
->type
== AS_SEQUENCE
)
495 leftmost
= seg
->as
[0];
500 /* Return 1 if there are any 4-byte ASes in the path */
501 bool aspath_has_as4(struct aspath
*aspath
)
503 struct assegment
*seg
= aspath
->segments
;
507 for (i
= 0; i
< seg
->length
; i
++)
508 if (seg
->as
[i
] > BGP_AS_MAX
)
515 /* Convert aspath structure to string expression. */
516 static void aspath_make_str_count(struct aspath
*as
, bool make_json
)
518 struct assegment
*seg
;
522 json_object
*jaspath_segments
= NULL
;
523 json_object
*jseg
= NULL
;
524 json_object
*jseg_list
= NULL
;
527 as
->json
= json_object_new_object();
528 jaspath_segments
= json_object_new_array();
534 json_object_string_add(as
->json
, "string", "Local");
535 json_object_object_add(as
->json
, "segments",
537 json_object_int_add(as
->json
, "length", 0);
539 as
->str
= XMALLOC(MTYPE_AS_STR
, 1);
547 /* ASN takes 5 to 10 chars plus separator, see below.
548 * If there is one differing segment type, we need an additional
549 * 2 chars for segment delimiters, and the final '\0'.
550 * Hopefully this is large enough to avoid hitting the realloc
551 * code below for most common sequences.
553 * This was changed to 10 after the well-known BGP assertion, which
554 * had hit some parts of the Internet in May of 2009.
556 #define ASN_STR_LEN (10 + 1)
557 str_size
= MAX(assegment_count_asns(seg
, 0) * ASN_STR_LEN
+ 2 + 1,
558 ASPATH_STR_DEFAULT_LEN
);
559 str_buf
= XMALLOC(MTYPE_AS_STR
, str_size
);
565 /* Check AS type validity. Set separator for segment */
572 case AS_CONFED_SEQUENCE
:
576 XFREE(MTYPE_AS_STR
, str_buf
);
579 json_object_free(as
->json
);
585 /* We might need to increase str_buf, particularly if path has
586 * differing segments types, our initial guesstimate above will
587 * have been wrong. Need 10 chars for ASN, a separator each and
588 * potentially two segment delimiters, plus a space between each
589 * segment and trailing zero.
591 * This definitely didn't work with the value of 5 bytes and
594 #define SEGMENT_STR_LEN(X) (((X)->length * ASN_STR_LEN) + 2 + 1 + 1)
595 if ((len
+ SEGMENT_STR_LEN(seg
)) > str_size
) {
596 str_size
= len
+ SEGMENT_STR_LEN(seg
);
597 str_buf
= XREALLOC(MTYPE_AS_STR
, str_buf
, str_size
);
600 #undef SEGMENT_STR_LEN
602 if (seg
->type
!= AS_SEQUENCE
)
604 str_buf
+ len
, str_size
- len
, "%c",
605 aspath_delimiter_char(seg
->type
, AS_SEG_START
));
608 jseg_list
= json_object_new_array();
610 /* write out the ASNs, with their separators, bar the last one*/
611 for (i
= 0; i
< seg
->length
; i
++) {
613 json_object_array_add(
615 json_object_new_int64(seg
->as
[i
]));
617 len
+= snprintf(str_buf
+ len
, str_size
- len
, "%u",
620 if (i
< (seg
->length
- 1))
621 len
+= snprintf(str_buf
+ len
, str_size
- len
,
626 jseg
= json_object_new_object();
627 json_object_string_add(
629 aspath_segment_type_str
[seg
->type
]);
630 json_object_object_add(jseg
, "list", jseg_list
);
631 json_object_array_add(jaspath_segments
, jseg
);
634 if (seg
->type
!= AS_SEQUENCE
)
636 str_buf
+ len
, str_size
- len
, "%c",
637 aspath_delimiter_char(seg
->type
, AS_SEG_END
));
639 len
+= snprintf(str_buf
+ len
, str_size
- len
, " ");
644 assert(len
< str_size
);
651 json_object_string_add(as
->json
, "string", str_buf
);
652 json_object_object_add(as
->json
, "segments", jaspath_segments
);
653 json_object_int_add(as
->json
, "length", aspath_count_hops(as
));
659 void aspath_str_update(struct aspath
*as
, bool make_json
)
661 XFREE(MTYPE_AS_STR
, as
->str
);
664 json_object_free(as
->json
);
668 aspath_make_str_count(as
, make_json
);
671 /* Intern allocated AS path. */
672 struct aspath
*aspath_intern(struct aspath
*aspath
)
676 /* Assert this AS path structure is not interned and has the string
677 representation built. */
678 assert(aspath
->refcnt
== 0);
681 /* Check AS path hash. */
682 find
= hash_get(ashash
, aspath
, hash_alloc_intern
);
691 /* Duplicate aspath structure. Created same aspath structure but
692 reference count and AS path string is cleared. */
693 struct aspath
*aspath_dup(struct aspath
*aspath
)
695 unsigned short buflen
= aspath
->str_len
+ 1;
698 new = XCALLOC(MTYPE_AS_PATH
, sizeof(struct aspath
));
701 if (aspath
->segments
)
702 new->segments
= assegment_dup_all(aspath
->segments
);
707 new->str
= XMALLOC(MTYPE_AS_STR
, buflen
);
708 new->str_len
= aspath
->str_len
;
710 /* copy the string data */
711 if (aspath
->str_len
> 0)
712 memcpy(new->str
, aspath
->str
, buflen
);
719 static void *aspath_hash_alloc(void *arg
)
721 const struct aspath
*aspath
= arg
;
724 /* Malformed AS path value. */
727 /* New aspath structure is needed. */
728 new = XMALLOC(MTYPE_AS_PATH
, sizeof(struct aspath
));
730 /* Reuse segments and string representation */
732 new->segments
= aspath
->segments
;
733 new->str
= aspath
->str
;
734 new->str_len
= aspath
->str_len
;
735 new->json
= aspath
->json
;
740 /* parse as-segment byte stream in struct assegment */
741 static int assegments_parse(struct stream
*s
, size_t length
,
742 struct assegment
**result
, int use32bit
)
744 struct assegment_header segh
;
745 struct assegment
*seg
, *prev
= NULL
, *head
= NULL
;
748 /* empty aspath (ie iBGP or somesuch) */
752 if (BGP_DEBUG(as4
, AS4_SEGMENT
))
754 "[AS4SEG] Parse aspath segment: got total byte length %lu",
755 (unsigned long)length
);
757 if ((STREAM_READABLE(s
) < length
)
758 || (STREAM_READABLE(s
) < AS_HEADER_SIZE
)
759 || (length
% AS16_VALUE_SIZE
))
762 while (bytes
< length
) {
766 if ((length
- bytes
) <= AS_HEADER_SIZE
) {
768 assegment_free_all(head
);
772 /* softly softly, get the header first on its own */
773 segh
.type
= stream_getc(s
);
774 segh
.length
= stream_getc(s
);
776 seg_size
= ASSEGMENT_SIZE(segh
.length
, use32bit
);
778 if (BGP_DEBUG(as4
, AS4_SEGMENT
))
780 "[AS4SEG] Parse aspath segment: got type %d, length %d",
781 segh
.type
, segh
.length
);
784 if (((bytes
+ seg_size
) > length
)
785 /* 1771bis 4.3b: seg length contains one or more */
786 || (segh
.length
== 0)
787 /* Paranoia in case someone changes type of segment length.
788 * Shift both values by 0x10 to make the comparison operate
789 * on more, than 8 bits (otherwise it's a warning, bug
792 || ((sizeof(segh
.length
) > 1)
793 && (0x10 + segh
.length
> 0x10 + AS_SEGMENT_MAX
))) {
795 assegment_free_all(head
);
802 case AS_CONFED_SEQUENCE
:
807 assegment_free_all(head
);
811 /* now its safe to trust lengths */
812 seg
= assegment_new(segh
.type
, segh
.length
);
816 else /* it's the first segment */
819 for (i
= 0; i
< segh
.length
; i
++)
821 (use32bit
) ? stream_getl(s
) : stream_getw(s
);
825 if (BGP_DEBUG(as4
, AS4_SEGMENT
))
827 "[AS4SEG] Parse aspath segment: Bytes now: %lu",
828 (unsigned long)bytes
);
833 *result
= assegment_normalise(head
);
837 /* AS path parse function. pnt is a pointer to byte stream and length
838 is length of byte stream. If there is same AS path in the the AS
839 path hash then return it else make new AS path structure.
841 On error NULL is returned.
843 struct aspath
*aspath_parse(struct stream
*s
, size_t length
, int use32bit
)
848 /* If length is odd it's malformed AS path. */
849 /* Nit-picking: if (use32bit == 0) it is malformed if odd,
850 * otherwise its malformed when length is larger than 2 and (length-2)
851 * is not dividable by 4.
852 * But... this time we're lazy
854 if (length
% AS16_VALUE_SIZE
)
857 memset(&as
, 0, sizeof(as
));
858 if (assegments_parse(s
, length
, &as
.segments
, use32bit
) < 0)
861 /* If already same aspath exist then return it. */
862 find
= hash_get(ashash
, &as
, aspath_hash_alloc
);
864 /* if the aspath was already hashed free temporary memory. */
866 assegment_free_all(as
.segments
);
867 /* aspath_key_make() always updates the string */
868 XFREE(MTYPE_AS_STR
, as
.str
);
870 json_object_free(as
.json
);
880 static void assegment_data_put(struct stream
*s
, as_t
*as
, int num
,
884 assert(num
<= AS_SEGMENT_MAX
);
886 for (i
= 0; i
< num
; i
++)
888 stream_putl(s
, as
[i
]);
890 if (as
[i
] <= BGP_AS_MAX
)
891 stream_putw(s
, as
[i
]);
893 stream_putw(s
, BGP_AS_TRANS
);
897 static size_t assegment_header_put(struct stream
*s
, uint8_t type
, int length
)
900 assert(length
<= AS_SEGMENT_MAX
);
901 stream_putc(s
, type
);
902 lenp
= stream_get_endp(s
);
903 stream_putc(s
, length
);
907 /* write aspath data to stream */
908 size_t aspath_put(struct stream
*s
, struct aspath
*as
, int use32bit
)
910 struct assegment
*seg
= as
->segments
;
913 if (!seg
|| seg
->length
== 0)
917 * Hey, what do we do when we have > STREAM_WRITABLE(s) here?
918 * At the moment, we would write out a partial aspath, and our
920 * will complain and drop the session :-/
922 * The general assumption here is that many things tested will
923 * never happen. And, in real live, up to now, they have not.
925 while (seg
&& (ASSEGMENT_LEN(seg
, use32bit
) <= STREAM_WRITEABLE(s
))) {
926 struct assegment
*next
= seg
->next
;
931 /* Overlength segments have to be split up */
932 while ((seg
->length
- written
) > AS_SEGMENT_MAX
) {
933 assegment_header_put(s
, seg
->type
, AS_SEGMENT_MAX
);
934 assegment_data_put(s
, (seg
->as
+ written
),
935 AS_SEGMENT_MAX
, use32bit
);
936 written
+= AS_SEGMENT_MAX
;
937 bytes
+= ASSEGMENT_SIZE(AS_SEGMENT_MAX
, use32bit
);
940 /* write the final segment, probably is also the first
942 lenp
= assegment_header_put(s
, seg
->type
,
943 seg
->length
- written
);
944 assegment_data_put(s
, (seg
->as
+ written
),
945 seg
->length
- written
, use32bit
);
947 /* Sequence-type segments can be 'packed' together
948 * Case of a segment which was overlength and split up
949 * will be missed here, but that doesn't matter.
951 while (next
&& ASSEGMENTS_PACKABLE(seg
, next
)) {
952 /* NB: We should never normally get here given
954 * normalise aspath data when parse them.
956 * safe than sorry. We potentially could call
957 * assegment_normalise here instead, but it's
959 * easier to do it on the fly here rather than
961 * the segment list twice every time we write
966 /* Next segment's data can fit in this one */
967 assegment_data_put(s
, next
->as
, next
->length
, use32bit
);
969 /* update the length of the segment header */
970 stream_putc_at(s
, lenp
,
971 seg
->length
- written
+ next
->length
);
972 asns_packed
+= next
->length
;
977 bytes
+= ASSEGMENT_SIZE(seg
->length
- written
+ asns_packed
,
984 /* This is for SNMP BGP4PATHATTRASPATHSEGMENT
985 * We have no way to manage the storage, so we use a static stream
986 * wrapper around aspath_put.
988 uint8_t *aspath_snmp_pathseg(struct aspath
*as
, size_t *varlen
)
990 #define SNMP_PATHSEG_MAX 1024
993 snmp_stream
= stream_new(SNMP_PATHSEG_MAX
);
995 stream_reset(snmp_stream
);
1001 aspath_put(snmp_stream
, as
, 0); /* use 16 bit for now here */
1003 *varlen
= stream_get_endp(snmp_stream
);
1004 return stream_pnt(snmp_stream
);
1007 static struct assegment
*aspath_aggregate_as_set_add(struct aspath
*aspath
,
1008 struct assegment
*asset
,
1013 /* If this is first AS set member, create new as-set segment. */
1014 if (asset
== NULL
) {
1015 asset
= assegment_new(AS_SET
, 1);
1016 if (!aspath
->segments
)
1017 aspath
->segments
= asset
;
1019 struct assegment
*seg
= aspath
->segments
;
1024 asset
->type
= AS_SET
;
1028 /* Check this AS value already exists or not. */
1029 for (i
= 0; i
< asset
->length
; i
++)
1030 if (asset
->as
[i
] == as
)
1034 asset
->as
= XREALLOC(MTYPE_AS_SEG_DATA
, asset
->as
,
1035 asset
->length
* AS_VALUE_SIZE
);
1036 asset
->as
[asset
->length
- 1] = as
;
1043 /* Modify as1 using as2 for aggregation. */
1044 struct aspath
*aspath_aggregate(struct aspath
*as1
, struct aspath
*as2
)
1050 struct assegment
*seg1
= as1
->segments
;
1051 struct assegment
*seg2
= as2
->segments
;
1052 struct aspath
*aspath
= NULL
;
1053 struct assegment
*asset
= NULL
;
1054 struct assegment
*prevseg
= NULL
;
1056 /* First of all check common leading sequence. */
1057 while (seg1
&& seg2
) {
1058 /* Check segment type. */
1059 if (seg1
->type
!= seg2
->type
)
1062 /* Minimum segment length. */
1063 minlen
= MIN(seg1
->length
, seg2
->length
);
1065 for (match
= 0; match
< minlen
; match
++)
1066 if (seg1
->as
[match
] != seg2
->as
[match
])
1070 struct assegment
*seg
= assegment_new(seg1
->type
, 0);
1072 seg
= assegment_append_asns(seg
, seg1
->as
, match
);
1075 aspath
= aspath_new();
1076 aspath
->segments
= seg
;
1078 prevseg
->next
= seg
;
1083 if (match
!= minlen
|| match
!= seg1
->length
1084 || seg1
->length
!= seg2
->length
)
1086 /* We are moving on to the next segment to reset match */
1095 aspath
= aspath_new();
1097 /* Make as-set using rest of all information. */
1100 for (i
= from
; i
< seg1
->length
; i
++)
1101 asset
= aspath_aggregate_as_set_add(aspath
, asset
,
1110 for (i
= from
; i
< seg2
->length
; i
++)
1111 asset
= aspath_aggregate_as_set_add(aspath
, asset
,
1118 assegment_normalise(aspath
->segments
);
1119 aspath_str_update(aspath
, false);
1123 /* When a BGP router receives an UPDATE with an MP_REACH_NLRI
1124 attribute, check the leftmost AS number in the AS_PATH attribute is
1125 or not the peer's AS number. */
1126 bool aspath_firstas_check(struct aspath
*aspath
, as_t asno
)
1128 if ((aspath
== NULL
) || (aspath
->segments
== NULL
))
1131 if (aspath
->segments
&& (aspath
->segments
->type
== AS_SEQUENCE
)
1132 && (aspath
->segments
->as
[0] == asno
))
1138 unsigned int aspath_get_first_as(struct aspath
*aspath
)
1140 if (aspath
== NULL
|| aspath
->segments
== NULL
)
1143 return aspath
->segments
->as
[0];
1146 unsigned int aspath_get_last_as(struct aspath
*aspath
)
1149 unsigned int last_as
= 0;
1150 const struct assegment
*seg
;
1152 if (aspath
== NULL
|| aspath
->segments
== NULL
)
1155 seg
= aspath
->segments
;
1158 if (seg
->type
== AS_SEQUENCE
|| seg
->type
== AS_CONFED_SEQUENCE
)
1159 for (i
= 0; i
< seg
->length
; i
++)
1160 last_as
= seg
->as
[i
];
1167 /* AS path loop check. If aspath contains asno then return >= 1. */
1168 int aspath_loop_check(struct aspath
*aspath
, as_t asno
)
1170 struct assegment
*seg
;
1173 if ((aspath
== NULL
) || (aspath
->segments
== NULL
))
1176 seg
= aspath
->segments
;
1181 for (i
= 0; i
< seg
->length
; i
++)
1182 if (seg
->as
[i
] == asno
)
1190 /* When all of AS path is private AS return 1. */
1191 bool aspath_private_as_check(struct aspath
*aspath
)
1193 struct assegment
*seg
;
1195 if (!(aspath
&& aspath
->segments
))
1198 seg
= aspath
->segments
;
1203 for (i
= 0; i
< seg
->length
; i
++) {
1204 if (!BGP_AS_IS_PRIVATE(seg
->as
[i
]))
1212 /* Return True if the entire ASPATH consist of the specified ASN */
1213 bool aspath_single_asn_check(struct aspath
*aspath
, as_t asn
)
1215 struct assegment
*seg
;
1217 if (!(aspath
&& aspath
->segments
))
1220 seg
= aspath
->segments
;
1225 for (i
= 0; i
< seg
->length
; i
++) {
1226 if (seg
->as
[i
] != asn
)
1234 /* Replace all instances of the target ASN with our own ASN */
1235 struct aspath
*aspath_replace_specific_asn(struct aspath
*aspath
,
1236 as_t target_asn
, as_t our_asn
)
1239 struct assegment
*seg
;
1241 new = aspath_dup(aspath
);
1242 seg
= new->segments
;
1247 for (i
= 0; i
< seg
->length
; i
++) {
1248 if (seg
->as
[i
] == target_asn
)
1249 seg
->as
[i
] = our_asn
;
1254 aspath_str_update(new, false);
1258 /* Replace all ASNs with our own ASN */
1259 struct aspath
*aspath_replace_all_asn(struct aspath
*aspath
, as_t our_asn
)
1262 struct assegment
*seg
;
1264 new = aspath_dup(aspath
);
1265 seg
= new->segments
;
1270 for (i
= 0; i
< seg
->length
; i
++)
1271 seg
->as
[i
] = our_asn
;
1276 aspath_str_update(new, false);
1280 /* Replace all private ASNs with our own ASN */
1281 struct aspath
*aspath_replace_private_asns(struct aspath
*aspath
, as_t asn
,
1285 struct assegment
*seg
;
1287 new = aspath_dup(aspath
);
1288 seg
= new->segments
;
1293 for (i
= 0; i
< seg
->length
; i
++) {
1294 /* Don't replace if public ASN or peer's ASN */
1295 if (BGP_AS_IS_PRIVATE(seg
->as
[i
])
1296 && (seg
->as
[i
] != peer_asn
))
1302 aspath_str_update(new, false);
1306 /* Remove all private ASNs */
1307 struct aspath
*aspath_remove_private_asns(struct aspath
*aspath
, as_t peer_asn
)
1310 struct assegment
*seg
;
1311 struct assegment
*new_seg
;
1312 struct assegment
*last_new_seg
;
1318 new = XCALLOC(MTYPE_AS_PATH
, sizeof(struct aspath
));
1322 last_new_seg
= NULL
;
1323 seg
= aspath
->segments
;
1327 for (i
= 0; i
< seg
->length
; i
++) {
1329 if (!BGP_AS_IS_PRIVATE(seg
->as
[i
]))
1331 /* ASN matches peer's.
1332 * Don't double-count if peer_asn is public.
1334 else if (seg
->as
[i
] == peer_asn
)
1338 // The entire segment is public so copy it
1339 if (public == seg
->length
)
1340 new_seg
= assegment_dup(seg
);
1342 // The segment is a mix of public and private ASNs. Copy as many
1344 // there are public ASNs then come back and fill in only the
1347 /* length needs to account for all retained ASNs
1348 * (public or peer_asn), not just public
1350 new_seg
= assegment_new(seg
->type
, (public + peer
));
1352 for (i
= 0; i
< seg
->length
; i
++) {
1353 // keep ASN if public or matches peer's ASN
1354 if (!BGP_AS_IS_PRIVATE(seg
->as
[i
])
1355 || (seg
->as
[i
] == peer_asn
)) {
1356 new_seg
->as
[j
] = seg
->as
[i
];
1362 // This is the first segment so set the aspath segments pointer
1365 new->segments
= new_seg
;
1367 last_new_seg
->next
= new_seg
;
1369 last_new_seg
= new_seg
;
1373 aspath_str_update(new, false);
1377 /* AS path confed check. If aspath contains confed set or sequence then return
1379 bool aspath_confed_check(struct aspath
*aspath
)
1381 struct assegment
*seg
;
1383 if (!(aspath
&& aspath
->segments
))
1386 seg
= aspath
->segments
;
1389 if (seg
->type
== AS_CONFED_SET
1390 || seg
->type
== AS_CONFED_SEQUENCE
)
1397 /* Leftmost AS path segment confed check. If leftmost AS segment is of type
1398 AS_CONFED_SEQUENCE or AS_CONFED_SET then return 1. */
1399 bool aspath_left_confed_check(struct aspath
*aspath
)
1402 if (!(aspath
&& aspath
->segments
))
1405 if ((aspath
->segments
->type
== AS_CONFED_SEQUENCE
)
1406 || (aspath
->segments
->type
== AS_CONFED_SET
))
1412 /* Merge as1 to as2. as2 should be uninterned aspath. */
1413 static struct aspath
*aspath_merge(struct aspath
*as1
, struct aspath
*as2
)
1415 struct assegment
*last
, *new;
1420 last
= new = assegment_dup_all(as1
->segments
);
1422 /* find the last valid segment */
1423 while (last
&& last
->next
)
1427 last
->next
= as2
->segments
;
1428 as2
->segments
= new;
1429 aspath_str_update(as2
, false);
1433 /* Prepend as1 to as2. as2 should be uninterned aspath. */
1434 struct aspath
*aspath_prepend(struct aspath
*as1
, struct aspath
*as2
)
1436 struct assegment
*as1segtail
;
1437 struct assegment
*as2segtail
;
1438 struct assegment
*as2seghead
;
1443 /* If as2 is empty, only need to dupe as1's chain onto as2 */
1444 if (as2
->segments
== NULL
) {
1445 as2
->segments
= assegment_dup_all(as1
->segments
);
1446 aspath_str_update(as2
, false);
1450 /* If as1 is empty AS, no prepending to do. */
1451 if (as1
->segments
== NULL
)
1454 /* find the tail as1's segment chain. */
1455 as1segtail
= as1
->segments
;
1456 while (as1segtail
&& as1segtail
->next
)
1457 as1segtail
= as1segtail
->next
;
1459 /* Delete any AS_CONFED_SEQUENCE segment from as2. */
1460 if (as1segtail
->type
== AS_SEQUENCE
1461 && as2
->segments
->type
== AS_CONFED_SEQUENCE
)
1462 as2
= aspath_delete_confed_seq(as2
);
1464 if (!as2
->segments
) {
1465 as2
->segments
= assegment_dup_all(as1
->segments
);
1466 aspath_str_update(as2
, false);
1470 /* Compare last segment type of as1 and first segment type of as2. */
1471 if (as1segtail
->type
!= as2
->segments
->type
)
1472 return aspath_merge(as1
, as2
);
1474 if (as1segtail
->type
== AS_SEQUENCE
) {
1475 /* We have two chains of segments, as1->segments and seg2,
1476 * and we have to attach them together, merging the attaching
1477 * segments together into one.
1479 * 1. dupe as1->segments onto head of as2
1480 * 2. merge seg2's asns onto last segment of this new chain
1481 * 3. attach chain after seg2
1485 as2seghead
= as2
->segments
;
1487 /* dupe as1 onto as2's head */
1488 as2segtail
= as2
->segments
= assegment_dup_all(as1
->segments
);
1490 /* refind the tail of as2 */
1491 while (as2segtail
&& as2segtail
->next
)
1492 as2segtail
= as2segtail
->next
;
1494 /* merge the old head, seg2, into tail, seg1 */
1495 assegment_append_asns(as2segtail
, as2seghead
->as
,
1496 as2seghead
->length
);
1499 * bypass the merged seg2, and attach any chain after it
1500 * to chain descending from as2's head
1503 as2segtail
->next
= as2seghead
->next
;
1505 /* as2->segments is now referenceless and useless */
1506 assegment_free(as2seghead
);
1508 /* we've now prepended as1's segment chain to as2, merging
1509 * the inbetween AS_SEQUENCE of seg2 in the process
1511 aspath_str_update(as2
, false);
1514 /* AS_SET merge code is needed at here. */
1515 return aspath_merge(as1
, as2
);
1517 /* XXX: Ermmm, what if as1 has multiple segments?? */
1522 /* Iterate over AS_PATH segments and wipe all occurrences of the
1523 * listed AS numbers. Hence some segments may lose some or even
1524 * all data on the way, the operation is implemented as a smarter
1525 * version of aspath_dup(), which allocates memory to hold the new
1526 * data, not the original. The new AS path is returned.
1528 struct aspath
*aspath_filter_exclude(struct aspath
*source
,
1529 struct aspath
*exclude_list
)
1531 struct assegment
*srcseg
, *exclseg
, *lastseg
;
1532 struct aspath
*newpath
;
1534 newpath
= aspath_new();
1537 for (srcseg
= source
->segments
; srcseg
; srcseg
= srcseg
->next
) {
1538 unsigned i
, y
, newlen
= 0, done
= 0, skip_as
;
1539 struct assegment
*newseg
;
1541 /* Find out, how much ASns are we going to pick from this
1543 * We can't perform filtering right inline, because the size of
1544 * the new segment isn't known at the moment yet.
1546 for (i
= 0; i
< srcseg
->length
; i
++) {
1548 for (exclseg
= exclude_list
->segments
;
1549 exclseg
&& !skip_as
; exclseg
= exclseg
->next
)
1550 for (y
= 0; y
< exclseg
->length
; y
++)
1551 if (srcseg
->as
[i
] == exclseg
->as
[y
]) {
1553 // There's no sense in testing
1554 // the rest of exclusion list,
1561 /* newlen is now the number of ASns to copy */
1565 /* Actual copying. Allocate memory and iterate once more,
1566 * performing filtering. */
1567 newseg
= assegment_new(srcseg
->type
, newlen
);
1568 for (i
= 0; i
< srcseg
->length
; i
++) {
1570 for (exclseg
= exclude_list
->segments
;
1571 exclseg
&& !skip_as
; exclseg
= exclseg
->next
)
1572 for (y
= 0; y
< exclseg
->length
; y
++)
1573 if (srcseg
->as
[i
] == exclseg
->as
[y
]) {
1579 newseg
->as
[done
++] = srcseg
->as
[i
];
1581 /* At his point newlen must be equal to done, and both must be
1583 * the filtered segment to the gross result. */
1585 newpath
->segments
= newseg
;
1587 lastseg
->next
= newseg
;
1590 aspath_str_update(newpath
, false);
1591 /* We are happy returning even an empty AS_PATH, because the
1593 * might expect this very behaviour. There's a mean to avoid this, if
1595 * by having a match rule against certain AS_PATH regexps in the
1598 aspath_free(source
);
1602 /* Add specified AS to the leftmost of aspath. */
1603 static struct aspath
*aspath_add_asns(struct aspath
*aspath
, as_t asno
,
1604 uint8_t type
, unsigned num
)
1606 struct assegment
*assegment
= aspath
->segments
;
1609 if (assegment
&& assegment
->type
== type
) {
1610 /* extend existing segment */
1612 assegment_prepend_asns(aspath
->segments
, asno
, num
);
1614 /* prepend with new segment */
1615 struct assegment
*newsegment
= assegment_new(type
, num
);
1616 for (i
= 0; i
< num
; i
++)
1617 newsegment
->as
[i
] = asno
;
1619 /* insert potentially replacing empty segment */
1620 if (assegment
&& assegment
->length
== 0) {
1621 newsegment
->next
= assegment
->next
;
1622 assegment_free(assegment
);
1624 newsegment
->next
= assegment
;
1625 aspath
->segments
= newsegment
;
1628 aspath_str_update(aspath
, false);
1632 /* Add specified AS to the leftmost of aspath num times. */
1633 struct aspath
*aspath_add_seq_n(struct aspath
*aspath
, as_t asno
, unsigned num
)
1635 return aspath_add_asns(aspath
, asno
, AS_SEQUENCE
, num
);
1638 /* Add specified AS to the leftmost of aspath. */
1639 struct aspath
*aspath_add_seq(struct aspath
*aspath
, as_t asno
)
1641 return aspath_add_asns(aspath
, asno
, AS_SEQUENCE
, 1);
1644 /* Compare leftmost AS value for MED check. If as1's leftmost AS and
1645 as2's leftmost AS is same return 1. */
1646 bool aspath_cmp_left(const struct aspath
*aspath1
, const struct aspath
*aspath2
)
1648 const struct assegment
*seg1
;
1649 const struct assegment
*seg2
;
1651 if (!(aspath1
&& aspath2
))
1654 seg1
= aspath1
->segments
;
1655 seg2
= aspath2
->segments
;
1657 /* If both paths are originated in this AS then we do want to compare
1662 /* find first non-confed segments for each */
1663 while (seg1
&& ((seg1
->type
== AS_CONFED_SEQUENCE
)
1664 || (seg1
->type
== AS_CONFED_SET
)))
1667 while (seg2
&& ((seg2
->type
== AS_CONFED_SEQUENCE
)
1668 || (seg2
->type
== AS_CONFED_SET
)))
1672 if (!(seg1
&& seg2
&& (seg1
->type
== AS_SEQUENCE
)
1673 && (seg2
->type
== AS_SEQUENCE
)))
1676 if (seg1
->as
[0] == seg2
->as
[0])
1682 /* Truncate an aspath after a number of hops, and put the hops remaining
1683 * at the front of another aspath. Needed for AS4 compat.
1685 * Returned aspath is a /new/ aspath, which should either by free'd or
1686 * interned by the caller, as desired.
1688 struct aspath
*aspath_reconcile_as4(struct aspath
*aspath
,
1689 struct aspath
*as4path
)
1691 struct assegment
*seg
, *newseg
, *prevseg
= NULL
;
1692 struct aspath
*newpath
= NULL
, *mergedpath
;
1693 int hops
, cpasns
= 0;
1695 if (!aspath
|| !as4path
)
1698 seg
= aspath
->segments
;
1700 /* CONFEDs should get reconciled too.. */
1701 hops
= (aspath_count_hops(aspath
) + aspath_count_confeds(aspath
))
1702 - aspath_count_hops(as4path
);
1705 if (BGP_DEBUG(as4
, AS4
))
1707 EC_BGP_ASPATH_FEWER_HOPS
,
1708 "[AS4] Fewer hops in AS_PATH than NEW_AS_PATH");
1709 /* Something's gone wrong. The RFC says we should now ignore
1711 * which is daft behaviour - it contains vital loop-detection
1712 * information which must have been removed from AS_PATH.
1714 hops
= aspath_count_hops(aspath
);
1718 newpath
= aspath_dup(as4path
);
1719 aspath_str_update(newpath
, false);
1723 if (BGP_DEBUG(as4
, AS4
))
1725 "[AS4] got AS_PATH %s and AS4_PATH %s synthesizing now",
1726 aspath
->str
, as4path
->str
);
1728 while (seg
&& hops
> 0) {
1729 switch (seg
->type
) {
1733 cpasns
= seg
->length
;
1735 case AS_CONFED_SEQUENCE
:
1736 /* Should never split a confed-sequence, if hop-count
1737 * suggests we must then something's gone wrong
1740 * Most important goal is to preserve AS_PATHs prime
1742 * as loop-detector, so we fudge the numbers so that the
1744 * confed-sequence is merged in.
1746 if (hops
< seg
->length
) {
1747 if (BGP_DEBUG(as4
, AS4
))
1749 "[AS4] AS4PATHmangle: AS_CONFED_SEQUENCE falls across 2/4 ASN boundary somewhere, broken..");
1754 cpasns
= MIN(seg
->length
, hops
);
1755 hops
-= seg
->length
;
1758 assert(cpasns
<= seg
->length
);
1760 newseg
= assegment_new(seg
->type
, 0);
1761 newseg
= assegment_append_asns(newseg
, seg
->as
, cpasns
);
1764 newpath
= aspath_new();
1765 newpath
->segments
= newseg
;
1767 prevseg
->next
= newseg
;
1773 /* We may be able to join some segments here, and we must
1774 * do this because... we want normalised aspaths in out hash
1775 * and we do not want to stumble in aspath_put.
1777 mergedpath
= aspath_merge(newpath
, aspath_dup(as4path
));
1778 aspath_free(newpath
);
1779 mergedpath
->segments
= assegment_normalise(mergedpath
->segments
);
1780 aspath_str_update(mergedpath
, false);
1782 if (BGP_DEBUG(as4
, AS4
))
1783 zlog_debug("[AS4] result of synthesizing is %s",
1789 /* Compare leftmost AS value for MED check. If as1's leftmost AS and
1790 as2's leftmost AS is same return 1. (confederation as-path
1792 bool aspath_cmp_left_confed(const struct aspath
*aspath1
,
1793 const struct aspath
*aspath2
)
1795 if (!(aspath1
&& aspath2
))
1798 if (!(aspath1
->segments
&& aspath2
->segments
))
1801 if ((aspath1
->segments
->type
!= AS_CONFED_SEQUENCE
)
1802 || (aspath2
->segments
->type
!= AS_CONFED_SEQUENCE
))
1805 if (aspath1
->segments
->as
[0] == aspath2
->segments
->as
[0])
1811 /* Delete all AS_CONFED_SEQUENCE/SET segments from aspath.
1812 * RFC 5065 section 4.1.c.1
1814 * 1) if any path segments of the AS_PATH are of the type
1815 * AS_CONFED_SEQUENCE or AS_CONFED_SET, those segments MUST be
1816 * removed from the AS_PATH attribute, leaving the sanitized
1817 * AS_PATH attribute to be operated on by steps 2, 3 or 4.
1819 struct aspath
*aspath_delete_confed_seq(struct aspath
*aspath
)
1821 struct assegment
*seg
, *prev
, *next
;
1822 char removed_confed_segment
;
1824 if (!(aspath
&& aspath
->segments
))
1827 seg
= aspath
->segments
;
1828 removed_confed_segment
= 0;
1835 if (seg
->type
== AS_CONFED_SEQUENCE
1836 || seg
->type
== AS_CONFED_SET
) {
1837 /* This is the first segment in the aspath */
1838 if (aspath
->segments
== seg
)
1839 aspath
->segments
= seg
->next
;
1841 prev
->next
= seg
->next
;
1843 assegment_free(seg
);
1844 removed_confed_segment
= 1;
1851 if (removed_confed_segment
)
1852 aspath_str_update(aspath
, false);
1857 /* Add new AS number to the leftmost part of the aspath as
1858 AS_CONFED_SEQUENCE. */
1859 struct aspath
*aspath_add_confed_seq(struct aspath
*aspath
, as_t asno
)
1861 return aspath_add_asns(aspath
, asno
, AS_CONFED_SEQUENCE
, 1);
1864 /* Add new as value to as path structure. */
1865 static void aspath_as_add(struct aspath
*as
, as_t asno
)
1867 struct assegment
*seg
= as
->segments
;
1872 /* Last segment search procedure. */
1876 assegment_append_asns(seg
, &asno
, 1);
1879 /* Add new as segment to the as path. */
1880 static void aspath_segment_add(struct aspath
*as
, int type
)
1882 struct assegment
*seg
= as
->segments
;
1883 struct assegment
*new = assegment_new(type
, 0);
1893 struct aspath
*aspath_empty(void)
1895 return aspath_parse(NULL
, 0, 1); /* 32Bit ;-) */
1898 struct aspath
*aspath_empty_get(void)
1900 struct aspath
*aspath
;
1902 aspath
= aspath_new();
1903 aspath_make_str_count(aspath
, false);
1907 unsigned long aspath_count(void)
1909 return ashash
->count
;
1913 Theoretically, one as path can have:
1915 One BGP packet size should be less than 4096.
1916 One BGP attribute size should be less than 4096 - BGP header size.
1917 One BGP aspath size should be less than 4096 - BGP header size -
1918 BGP mandantry attribute size.
1921 /* AS path string lexical token enum. */
1926 as_token_confed_seq_start
,
1927 as_token_confed_seq_end
,
1928 as_token_confed_set_start
,
1929 as_token_confed_set_end
,
1933 /* Return next token and point for string parse. */
1934 static const char *aspath_gettoken(const char *buf
, enum as_token
*token
,
1935 unsigned long *asno
)
1937 const char *p
= buf
;
1939 /* Skip separators (space for sequences, ',' for sets). */
1940 while (isspace((unsigned char)*p
) || *p
== ',')
1943 /* Check the end of the string and type specify characters
1949 *token
= as_token_set_start
;
1953 *token
= as_token_set_end
;
1957 *token
= as_token_confed_seq_start
;
1961 *token
= as_token_confed_seq_end
;
1965 *token
= as_token_confed_set_start
;
1969 *token
= as_token_confed_set_end
;
1974 /* Check actual AS value. */
1975 if (isdigit((unsigned char)*p
)) {
1978 *token
= as_token_asval
;
1982 while (isdigit((unsigned char)*p
)) {
1984 asval
+= (*p
- '0');
1991 /* There is no match then return unknown token. */
1992 *token
= as_token_unknown
;
1997 struct aspath
*aspath_str2aspath(const char *str
)
1999 enum as_token token
= as_token_unknown
;
2000 unsigned short as_type
;
2001 unsigned long asno
= 0;
2002 struct aspath
*aspath
;
2005 aspath
= aspath_new();
2007 /* We start default type as AS_SEQUENCE. */
2008 as_type
= AS_SEQUENCE
;
2011 while ((str
= aspath_gettoken(str
, &token
, &asno
)) != NULL
) {
2013 case as_token_asval
:
2015 aspath_segment_add(aspath
, as_type
);
2018 aspath_as_add(aspath
, asno
);
2020 case as_token_set_start
:
2022 aspath_segment_add(aspath
, as_type
);
2025 case as_token_set_end
:
2026 as_type
= AS_SEQUENCE
;
2029 case as_token_confed_seq_start
:
2030 as_type
= AS_CONFED_SEQUENCE
;
2031 aspath_segment_add(aspath
, as_type
);
2034 case as_token_confed_seq_end
:
2035 as_type
= AS_SEQUENCE
;
2038 case as_token_confed_set_start
:
2039 as_type
= AS_CONFED_SET
;
2040 aspath_segment_add(aspath
, as_type
);
2043 case as_token_confed_set_end
:
2044 as_type
= AS_SEQUENCE
;
2047 case as_token_unknown
:
2049 aspath_free(aspath
);
2054 aspath_make_str_count(aspath
, false);
2059 /* Make hash value by raw aspath data. */
2060 unsigned int aspath_key_make(const void *p
)
2062 const struct aspath
*aspath
= p
;
2063 unsigned int key
= 0;
2066 aspath_str_update((struct aspath
*)aspath
, false);
2068 key
= jhash(aspath
->str
, aspath
->str_len
, 2334325);
2073 /* If two aspath have same value then return 1 else return 0 */
2074 bool aspath_cmp(const void *arg1
, const void *arg2
)
2076 const struct assegment
*seg1
= ((const struct aspath
*)arg1
)->segments
;
2077 const struct assegment
*seg2
= ((const struct aspath
*)arg2
)->segments
;
2079 while (seg1
|| seg2
) {
2081 if ((!seg1
&& seg2
) || (seg1
&& !seg2
))
2083 if (seg1
->type
!= seg2
->type
)
2085 if (seg1
->length
!= seg2
->length
)
2087 for (i
= 0; i
< seg1
->length
; i
++)
2088 if (seg1
->as
[i
] != seg2
->as
[i
])
2096 /* AS path hash initialize. */
2097 void aspath_init(void)
2099 ashash
= hash_create_size(32768, aspath_key_make
, aspath_cmp
,
2103 void aspath_finish(void)
2105 hash_clean(ashash
, (void (*)(void *))aspath_free
);
2110 stream_free(snmp_stream
);
2113 /* return and as path value */
2114 const char *aspath_print(struct aspath
*as
)
2116 return (as
? as
->str
: NULL
);
2119 /* Printing functions */
2120 /* Feed the AS_PATH to the vty; the suffix string follows it only in case
2121 * AS_PATH wasn't empty.
2123 void aspath_print_vty(struct vty
*vty
, const char *format
, struct aspath
*as
,
2127 vty_out(vty
, format
, as
->str
);
2128 if (as
->str_len
&& strlen(suffix
))
2129 vty_out(vty
, "%s", suffix
);
2132 static void aspath_show_all_iterator(struct hash_bucket
*bucket
,
2137 as
= (struct aspath
*)bucket
->data
;
2139 vty_out(vty
, "[%p:%u] (%ld) ", (void *)bucket
, bucket
->key
, as
->refcnt
);
2140 vty_out(vty
, "%s\n", as
->str
);
2143 /* Print all aspath and hash information. This function is used from
2144 `show [ip] bgp paths' command. */
2145 void aspath_print_all_vty(struct vty
*vty
)
2147 hash_iterate(ashash
, (void (*)(struct hash_bucket
*,
2148 void *))aspath_show_all_iterator
,
2152 static struct aspath
*bgp_aggr_aspath_lookup(struct bgp_aggregate
*aggregate
,
2153 struct aspath
*aspath
)
2155 return hash_lookup(aggregate
->aspath_hash
, aspath
);
2158 static void *bgp_aggr_aspath_hash_alloc(void *p
)
2160 struct aspath
*ref
= (struct aspath
*)p
;
2161 struct aspath
*aspath
= NULL
;
2163 aspath
= aspath_dup(ref
);
2167 static void bgp_aggr_aspath_prepare(struct hash_bucket
*hb
, void *arg
)
2169 struct aspath
*hb_aspath
= hb
->data
;
2170 struct aspath
**aggr_aspath
= arg
;
2173 *aggr_aspath
= aspath_aggregate(*aggr_aspath
, hb_aspath
);
2175 *aggr_aspath
= aspath_dup(hb_aspath
);
2178 void bgp_aggr_aspath_remove(void *arg
)
2180 struct aspath
*aspath
= arg
;
2182 aspath_free(aspath
);
2185 void bgp_compute_aggregate_aspath(struct bgp_aggregate
*aggregate
,
2186 struct aspath
*aspath
)
2188 bgp_compute_aggregate_aspath_hash(aggregate
, aspath
);
2190 bgp_compute_aggregate_aspath_val(aggregate
);
2194 void bgp_compute_aggregate_aspath_hash(struct bgp_aggregate
*aggregate
,
2195 struct aspath
*aspath
)
2197 struct aspath
*aggr_aspath
= NULL
;
2199 if ((aggregate
== NULL
) || (aspath
== NULL
))
2202 /* Create hash if not already created.
2204 if (aggregate
->aspath_hash
== NULL
)
2205 aggregate
->aspath_hash
= hash_create(
2206 aspath_key_make
, aspath_cmp
,
2207 "BGP Aggregator as-path hash");
2209 aggr_aspath
= bgp_aggr_aspath_lookup(aggregate
, aspath
);
2210 if (aggr_aspath
== NULL
) {
2211 /* Insert as-path into hash.
2213 aggr_aspath
= hash_get(aggregate
->aspath_hash
, aspath
,
2214 bgp_aggr_aspath_hash_alloc
);
2217 /* Increment reference counter.
2219 aggr_aspath
->refcnt
++;
2222 void bgp_compute_aggregate_aspath_val(struct bgp_aggregate
*aggregate
)
2224 if (aggregate
== NULL
)
2226 /* Re-compute aggregate's as-path.
2228 if (aggregate
->aspath
) {
2229 aspath_free(aggregate
->aspath
);
2230 aggregate
->aspath
= NULL
;
2232 if (aggregate
->aspath_hash
2233 && aggregate
->aspath_hash
->count
) {
2234 hash_iterate(aggregate
->aspath_hash
,
2235 bgp_aggr_aspath_prepare
,
2236 &aggregate
->aspath
);
2240 void bgp_remove_aspath_from_aggregate(struct bgp_aggregate
*aggregate
,
2241 struct aspath
*aspath
)
2243 struct aspath
*aggr_aspath
= NULL
;
2244 struct aspath
*ret_aspath
= NULL
;
2247 || (!aggregate
->aspath_hash
)
2251 /* Look-up the aspath in the hash.
2253 aggr_aspath
= bgp_aggr_aspath_lookup(aggregate
, aspath
);
2255 aggr_aspath
->refcnt
--;
2257 if (aggr_aspath
->refcnt
== 0) {
2258 ret_aspath
= hash_release(aggregate
->aspath_hash
,
2260 aspath_free(ret_aspath
);
2263 /* Remove aggregate's old as-path.
2265 aspath_free(aggregate
->aspath
);
2266 aggregate
->aspath
= NULL
;
2268 bgp_compute_aggregate_aspath_val(aggregate
);
2273 void bgp_remove_aspath_from_aggregate_hash(struct bgp_aggregate
*aggregate
,
2274 struct aspath
*aspath
)
2276 struct aspath
*aggr_aspath
= NULL
;
2277 struct aspath
*ret_aspath
= NULL
;
2280 || (!aggregate
->aspath_hash
)
2284 /* Look-up the aspath in the hash.
2286 aggr_aspath
= bgp_aggr_aspath_lookup(aggregate
, aspath
);
2288 aggr_aspath
->refcnt
--;
2290 if (aggr_aspath
->refcnt
== 0) {
2291 ret_aspath
= hash_release(aggregate
->aspath_hash
,
2293 aspath_free(ret_aspath
);