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authorOndrej Zajicek <santiago@crfreenet.org>2009-04-17 01:48:36 +0200
committerOndrej Zajicek <santiago@crfreenet.org>2009-04-17 01:48:36 +0200
commitc8a6b9a3d199444fd45879dd5cc5ececd9624822 (patch)
tree1ada700f499ec771ea68873c87b51bc71b455a27 /doc/bird.sgml
parent024c310b537abc3ddbac3054de71fd759d422824 (diff)
downloadbird-c8a6b9a3d199444fd45879dd5cc5ececd9624822.tar
bird-c8a6b9a3d199444fd45879dd5cc5ececd9624822.zip
Rewrite of buggy AS path matching.
Old AS path maching supposes thath AS number appears only once in AS path, but that is not true. It also contains some bugs related to AS path sets. New code does not use any assumptions about semantic structure of AS path. It is asymptotically slower than the old code, but on real paths it is not significant. It also allows '?' for matching one arbitrary AS number.
Diffstat (limited to 'doc/bird.sgml')
-rw-r--r--doc/bird.sgml3
1 files changed, 2 insertions, 1 deletions
diff --git a/doc/bird.sgml b/doc/bird.sgml
index 1cb3fc4..70d970f 100644
--- a/doc/bird.sgml
+++ b/doc/bird.sgml
@@ -549,7 +549,8 @@ incompatible with each other (that is to prevent you from shooting in the foot).
(using <cf>path &tilde; [= 2 3 5 * =]</cf> syntax). The masks
resemble wildcard patterns as used by UNIX shells. Autonomous
system numbers match themselves, <cf/*/ matches any (even empty)
- sequence of arbitrary AS numbers. For example, if <cf>bgp_path</cf> is 4 3 2 1, then:
+ sequence of arbitrary AS numbers and <cf/?/ matches one arbitrary AS number.
+ For example, if <cf>bgp_path</cf> is 4 3 2 1, then:
<tt>bgp_path &tilde; [= * 4 3 * =]</tt> is true, but
<tt>bgp_path &tilde; [= * 4 5 * =]</tt> is false.
There is also old syntax that uses / .. / instead of [= .. =] and ? instead of *.