Current implementation handles flowspec prefix length and offset only
in bytes, but RFC 8956 (Dissemination of Flow Specification Rules for
IPv6) Section 3.1 [1] and example in Section 3.8.2 [2] states the
pattern should begin right after offset *bits*.
For example, pattern "::1:1234:5678:9800:0/60-104" is currently
serialized as "02 68 3c 01 12 34 56 78 98", but it should shift its
pattern 4 more bits to the left: "02 68 3c 11 23 45 67 89 80".
This patch implements shifting left/right for IPv6 type and use it to
correct the behaviour. Test data are replaced with the correct ones.
Minor changes and test vectors done by committer.
[1]: https://www.rfc-editor.org/rfc/rfc8956.html#section-3.1
[2]: https://www.rfc-editor.org/rfc/rfc8956.html#section-3.8.2
For numeric operators, comma is used for disjunction in expressions like
"10, 20, 30..40". But for bitmask operators, comma is used for
conjunction in a way that does not really make much sense. Use always
explicit logical operators (&& and ||) to connect bitmask operators.
Thanks to Matt Corallo for the bugreport.
During NLRI parsing of IPv6 Flowspec, dst prefix was not properly
extracted from NLRI, therefore a received flow was stored in a different
position in flowspec routing table, and was not reachable by command
'show route <flow>'.
Add proper prefix part accessors to flowspec code and use them from BGP
NLRI parsing code.
Thanks to Alex D. for the bugreport.
