New LSA checksumming code separates generic Fletcher-16 and OSPF-specific
code and avoids back and forth endianity conversions, making it much more
readable and also several times faster.
Prior to this patch, BIRD validates the OSPF LSA checksum by calculating
a new checksum and comparing it with the checksum in the header. Due to
the specifics of the Fletcher checksum used in OSPF, this is not
necessarily correct as the checkbytes in the header may be calculated via
a different means and end up with a different value that is nonetheless
still correct.
The documented means of validating the checksum as specified in RFC 905
B.4 is to calculate c0 and c1 from the unchanged contents of the packet,
which must result in a zero value to be considered valid.
Thanks to Chris Boot for the patch.
I/O:
- BSD: specify src addr on IP sockets by IP_HDRINCL
- BSD: specify src addr on UDP sockets by IP_SENDSRCADDR
- Linux: specify src addr on IP/UDP sockets by IP_PKTINFO
- IPv6: specify src addr on IP/UDP sockets by IPV6_PKTINFO
- Alternative SKF_BIND flag for binding to IP address
- Allows IP/UDP sockets without tx_hook, on these
sockets a packet is discarded when TX queue is full
- Use consistently SOL_ for socket layer values.
OSPF:
- Packet src addr is always explicitly set
- Support for secondary addresses in BSD
- Dynamic RX/TX buffers
- Fixes some minor buffer overruns
- Interface option 'tx length'
- Names for vlink pseudoifaces (vlinkX)
- Vlinks use separate socket for TX
- Vlinks do not use fixed associated iface
- Fixes TTL for direct unicast packets
- Fixes DONTROUTE for OSPF sockets
- Use ifa->ifname instead of ifa->iface->name
- metric is 3 byte long now
- summary lsa originating
- more OSPF areas possible
- virtual links
- better E1/E2 routes handling
- some bug fixes..
I have to do:
- md5 auth (last mandatory item from rfc2328)
- !!!!DEBUG!!!!! (mainly virtual link system has probably a lot of bugs)
- 2328 appendig E
