From 3fd6b24ace319b139ec3c4e3031a5f05d21e304e Mon Sep 17 00:00:00 2001 From: Jozsef Kadlecsik Date: Tue, 15 Jun 2010 13:30:55 +0200 Subject: ipset 5 in an almost ready state - milestone Reworked protocol and internal interfaces, missing set types added, backward compatibility verified, lots of tests added (and thanks to the tests, bugs fixed), even the manpage is rewritten ;-). Countless changes everywhere... The missing bits before announcing ipset 5: - net namespace support - new iptables/ip6tables extension library - iptables/ip6tables match and target tests (backward/forward compatibility) - tests on catching syntax errors --- kernel/include/linux/netfilter/ip_set_jhash.h | 152 ++++++++++---------------- 1 file changed, 58 insertions(+), 94 deletions(-) (limited to 'kernel/include/linux/netfilter/ip_set_jhash.h') diff --git a/kernel/include/linux/netfilter/ip_set_jhash.h b/kernel/include/linux/netfilter/ip_set_jhash.h index 90bfcc3..d5e0d6d 100644 --- a/kernel/include/linux/netfilter/ip_set_jhash.h +++ b/kernel/include/linux/netfilter/ip_set_jhash.h @@ -1,7 +1,6 @@ #ifndef _LINUX_JHASH_H #define _LINUX_JHASH_H - -/* jhash.h: Jenkins hash support. +/* jhash.c: Jenkins hash support. * * Copyright (C) 2006. Bob Jenkins (bob_jenkins@burtleburtle.net) * @@ -17,141 +16,106 @@ * if SELF_TEST is defined. You can use this free for any purpose. It's in * the public domain. It has no warranty. * - * Copyright (C) 2009 Jozsef Kadlecsik (kadlec@blackhole.kfki.hu) + * Copyright (C) 2009-2010 Jozsef Kadlecsik (kadlec@blackhole.kfki.hu) * * I've modified Bob's hash to be useful in the Linux kernel, and - * any bugs present are my fault. Jozsef + * any bugs present are my fault. The generic jhash is left out intentionally. + * Jozsef */ - -#define __rot(x,k) (((x)<<(k)) | ((x)>>(32-(k)))) - -/* __jhash_mix - mix 3 32-bit values reversibly. */ -#define __jhash_mix(a,b,c) \ -{ \ - a -= c; a ^= __rot(c, 4); c += b; \ - b -= a; b ^= __rot(a, 6); a += c; \ - c -= b; c ^= __rot(b, 8); b += a; \ - a -= c; a ^= __rot(c,16); c += b; \ - b -= a; b ^= __rot(a,19); a += c; \ - c -= b; c ^= __rot(b, 4); b += a; \ +#ifdef __KERNEL__ +#include + +/* Best hash sizes are of power of two */ +#define jhash_size(n) ((u32)1<<(n)) +/* Mask the hash value, i.e (value & jhash_mask(n)) instead of (value % n) */ +#define jhash_mask(n) (jhash_size(n)-1) + +/* __jhash_rot - rotate 32 bit */ +#define __jhash_rot(x,k) (((x)<<(k)) | ((x)>>(32-(k)))) + +/* __jhash_mix -- mix 3 32-bit values reversibly. */ +#define __jhash_mix(a,b,c) \ +{ \ + a -= c; a ^= __jhash_rot(c, 4); c += b; \ + b -= a; b ^= __jhash_rot(a, 6); a += c; \ + c -= b; c ^= __jhash_rot(b, 8); b += a; \ + a -= c; a ^= __jhash_rot(c,16); c += b; \ + b -= a; b ^= __jhash_rot(a,19); a += c; \ + c -= b; c ^= __jhash_rot(b, 4); b += a; \ } /* __jhash_final - final mixing of 3 32-bit values (a,b,c) into c */ -#define __jhash_final(a,b,c) \ -{ \ - c ^= b; c -= __rot(b,14); \ - a ^= c; a -= __rot(c,11); \ - b ^= a; b -= __rot(a,25); \ - c ^= b; c -= __rot(b,16); \ - a ^= c; a -= __rot(c,4); \ - b ^= a; b -= __rot(a,14); \ - c ^= b; c -= __rot(b,24); \ +#define __jhash_final(a,b,c) \ +{ \ + c ^= b; c -= __jhash_rot(b,14); \ + a ^= c; a -= __jhash_rot(c,11); \ + b ^= a; b -= __jhash_rot(a,25); \ + c ^= b; c -= __jhash_rot(b,16); \ + a ^= c; a -= __jhash_rot(c,4); \ + b ^= a; b -= __jhash_rot(a,14); \ + c ^= b; c -= __jhash_rot(b,24); \ } -/* An arbitrary value */ -#define JHASH_RANDOM_PARAM 0xdeadbeef - -/* The most generic version, hashes an arbitrary sequence - * of bytes. No alignment or length assumptions are made about - * the input key. The result depends on endianness. - */ -static inline u32 jhash(const void *key, u32 length, u32 initval) -{ - u32 a,b,c; - const u8 *k = key; - - /* Set up the internal state */ - a = b = c = JHASH_RANDOM_PARAM + length + initval; - - /* all but the last block: affect some 32 bits of (a,b,c) */ - while (length > 12) { - a += (k[0] + ((u32)k[1]<<8) + ((u32)k[2]<<16) + ((u32)k[3]<<24)); - b += (k[4] + ((u32)k[5]<<8) + ((u32)k[6]<<16) + ((u32)k[7]<<24)); - c += (k[8] + ((u32)k[9]<<8) + ((u32)k[10]<<16) + ((u32)k[11]<<24)); - __jhash_mix(a, b, c); - length -= 12; - k += 12; - } - - /* last block: affect all 32 bits of (c) */ - /* all the case statements fall through */ - switch (length) { - case 12: c += (u32)k[11]<<24; - case 11: c += (u32)k[10]<<16; - case 10: c += (u32)k[9]<<8; - case 9 : c += k[8]; - case 8 : b += (u32)k[7]<<24; - case 7 : b += (u32)k[6]<<16; - case 6 : b += (u32)k[5]<<8; - case 5 : b += k[4]; - case 4 : a += (u32)k[3]<<24; - case 3 : a += (u32)k[2]<<16; - case 2 : a += (u32)k[1]<<8; - case 1 : a += k[0]; - __jhash_final(a, b, c); - case 0 : - break; - } - - return c; -} +#define JHASH_INITVAL 0xdeadbeef -/* A special optimized version that handles 1 or more of u32s. - * The length parameter here is the number of u32s in the key. +/* jhash2 - hash an array of u32's + * @k: the key which must be an array of u32's + * @length: the number of u32's in the key + * @initval: the previous hash, or an arbitray value + * + * Returns the hash value of the key. */ static inline u32 jhash2(const u32 *k, u32 length, u32 initval) { u32 a, b, c; /* Set up the internal state */ - a = b = c = JHASH_RANDOM_PARAM + (length<<2) + initval; + a = b = c = JHASH_INITVAL + (length<<2) + initval; - /* handle most of the key */ + /* Handle most of the key */ while (length > 3) { a += k[0]; b += k[1]; c += k[2]; - __jhash_mix(a, b, c); + __jhash_mix(a,b,c); length -= 3; k += 3; } - - /* handle the last 3 u32's */ - /* all the case statements fall through */ - switch (length) { + + /* Handle the last 3 u32's: all the case statements fall through */ + switch(length) { case 3: c += k[2]; case 2: b += k[1]; case 1: a += k[0]; - __jhash_final(a, b, c); - case 0: /* case 0: nothing left to add */ + __jhash_final(a,b,c); + case 0: /* Nothing left to add */ break; } return c; } -/* A special ultra-optimized versions that knows they are hashing exactly - * 3, 2 or 1 word(s). - */ +/* jhash_3words - hash exactly 3, 2 or 1 word(s) */ static inline u32 jhash_3words(u32 a, u32 b, u32 c, u32 initval) { - a += JHASH_RANDOM_PARAM + initval; - b += JHASH_RANDOM_PARAM + initval; - c += JHASH_RANDOM_PARAM + initval; - - __jhash_final(a, b, c); + a += JHASH_INITVAL; + b += JHASH_INITVAL; + c += initval; + __jhash_final(a,b,c); + return c; } - static inline u32 jhash_2words(u32 a, u32 b, u32 initval) { - return jhash_3words(0, a, b, initval); + return jhash_3words(a, b, 0, initval); } static inline u32 jhash_1word(u32 a, u32 initval) { - return jhash_3words(0, 0, a, initval); + return jhash_3words(a, 0, 0, initval); } +#endif /* __KERNEL__ */ + #endif /* _LINUX_JHASH_H */ -- cgit v1.2.3