secure_seq: use SipHash in place of MD5

This gives a clear speed and security improvement. Siphash is both
faster and is more solid crypto than the aging MD5.

Rather than manually filling MD5 buffers, for IPv6, we simply create
a layout by a simple anonymous struct, for which gcc generates
rather efficient code. For IPv4, we pass the values directly to the
short input convenience functions.

64-bit x86_64:
[    1.683628] secure_tcpv6_sequence_number_md5# cycles: 99563527
[    1.717350] secure_tcp_sequence_number_md5# cycles: 92890502
[    1.741968] secure_tcpv6_sequence_number_siphash# cycles: 67825362
[    1.762048] secure_tcp_sequence_number_siphash# cycles: 67485526

32-bit x86:
[    1.600012] secure_tcpv6_sequence_number_md5# cycles: 103227892
[    1.634219] secure_tcp_sequence_number_md5# cycles: 94732544
[    1.669102] secure_tcpv6_sequence_number_siphash# cycles: 96299384
[    1.700165] secure_tcp_sequence_number_siphash# cycles: 86015473

Signed-off-by: Jason A. Donenfeld <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: David Miller <[email protected]>
Cc: David Laight <[email protected]>
Cc: Tom Herbert <[email protected]>
Cc: Hannes Frederic Sowa <[email protected]>
Cc: Eric Dumazet <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

0 files changed, 0 insertions, 0 deletions