From 345236211715ffb7cc28f6ff0b26acb90181e738 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Fri, 26 Aug 2016 18:00:00 +0200 Subject: src: add hash expression This is special expression that transforms an input expression into a 32-bit unsigned integer. This expression takes a modulus parameter to scale the result and the random seed so the hash result becomes harder to predict. You can use it to set the packet mark, eg. # nft add rule x y meta mark set jhash ip saddr . ip daddr mod 2 seed 0xdeadbeef You can combine this with maps too, eg. # nft add rule x y dnat to jhash ip saddr mod 2 seed 0xdeadbeef map { \ 0 : 192.168.20.100, \ 1 : 192.168.30.100 \ } Currently, this expression implements the jenkins hash implementation available in the Linux kernel: http://lxr.free-electrons.com/source/include/linux/jhash.h But it should be possible to extend it to support any other hash function type. Signed-off-by: Pablo Neira Ayuso --- src/Makefile.am | 1 + 1 file changed, 1 insertion(+) (limited to 'src/Makefile.am') diff --git a/src/Makefile.am b/src/Makefile.am index 241a078b..63bbef2c 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -36,6 +36,7 @@ nft_SOURCES = main.c \ proto.c \ payload.c \ exthdr.c \ + hash.c \ meta.c \ numgen.c \ ct.c \ -- cgit v1.2.3