diff options
Diffstat (limited to 'sys/gnu/fs/reiserfs/reiserfs_hashes.c')
| -rw-r--r-- | sys/gnu/fs/reiserfs/reiserfs_hashes.c | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/sys/gnu/fs/reiserfs/reiserfs_hashes.c b/sys/gnu/fs/reiserfs/reiserfs_hashes.c new file mode 100644 index 0000000..3545dbf --- /dev/null +++ b/sys/gnu/fs/reiserfs/reiserfs_hashes.c @@ -0,0 +1,217 @@ +/*- + * Copyright 2000 Hans Reiser + * See README for licensing and copyright details + * + * Ported to FreeBSD by Jean-Sébastien Pédron <jspedron@club-internet.fr> + * + * $FreeBSD$ + */ + +#include <gnu/fs/reiserfs/reiserfs_fs.h> + +/* + * Keyed 32-bit hash function using TEA in a Davis-Meyer function + * H0 = Key + * Hi = E Mi(Hi-1) + Hi-1 + * + * (see Applied Cryptography, 2nd edition, p448). + * + * Jeremy Fitzhardinge <jeremy@zip.com.au> 1998 + * + * Jeremy has agreed to the contents of README. -Hans + * Yura's function is added (04/07/2000) + */ + +/* + * keyed_hash + * yura_hash + * r5_hash + */ + +#define DELTA 0x9E3779B9 +#define FULLROUNDS 10 /* 32 is overkill, 16 is strong crypto */ +#define PARTROUNDS 6 /* 6 gets complete mixing */ + +/* a, b, c, d - data; h0, h1 - accumulated hash */ +#define TEACORE(rounds) \ + do { \ + int n; \ + uint32_t b0, b1; \ + uint32_t sum; \ + \ + n = rounds; \ + sum = 0; \ + b0 = h0; \ + b1 = h1; \ + \ + do { \ + sum += DELTA; \ + b0 += ((b1 << 4) + a) ^ (b1+sum) ^ ((b1 >> 5) + b); \ + b1 += ((b0 << 4) + c) ^ (b0+sum) ^ ((b0 >> 5) + d); \ + } while (--n); \ + \ + h0 += b0; \ + h1 += b1; \ + } while (0) + +uint32_t +keyed_hash(const signed char *msg, int len) +{ + uint32_t k[] = { 0x9464a485, 0x542e1a94, 0x3e846bff, 0xb75bcfc3 }; + + uint32_t h0, h1; + uint32_t a, b, c, d; + uint32_t pad; + int i; + + h0 = k[0]; + h1 = k[1]; + + pad = (uint32_t)len | ((uint32_t)len << 8); + pad |= pad << 16; + + while(len >= 16) { + a = (uint32_t)msg[ 0] | + (uint32_t)msg[ 1] << 8 | + (uint32_t)msg[ 2] << 16 | + (uint32_t)msg[ 3] << 24; + b = (uint32_t)msg[ 4] | + (uint32_t)msg[ 5] << 8 | + (uint32_t)msg[ 6] << 16 | + (uint32_t)msg[ 7] << 24; + c = (uint32_t)msg[ 8] | + (uint32_t)msg[ 9] << 8 | + (uint32_t)msg[10] << 16 | + (uint32_t)msg[11] << 24; + d = (uint32_t)msg[12] | + (uint32_t)msg[13] << 8 | + (uint32_t)msg[14] << 16 | + (uint32_t)msg[15] << 24; + + TEACORE(PARTROUNDS); + + len -= 16; + msg += 16; + } + + if (len >= 12) { + a = (uint32_t)msg[ 0] | + (uint32_t)msg[ 1] << 8 | + (uint32_t)msg[ 2] << 16 | + (uint32_t)msg[ 3] << 24; + b = (uint32_t)msg[ 4] | + (uint32_t)msg[ 5] << 8 | + (uint32_t)msg[ 6] << 16 | + (uint32_t)msg[ 7] << 24; + c = (uint32_t)msg[ 8] | + (uint32_t)msg[ 9] << 8 | + (uint32_t)msg[10] << 16 | + (uint32_t)msg[11] << 24; + + d = pad; + for(i = 12; i < len; i++) { + d <<= 8; + d |= msg[i]; + } + } else if (len >= 8) { + a = (uint32_t)msg[ 0] | + (uint32_t)msg[ 1] << 8 | + (uint32_t)msg[ 2] << 16 | + (uint32_t)msg[ 3] << 24; + b = (uint32_t)msg[ 4] | + (uint32_t)msg[ 5] << 8 | + (uint32_t)msg[ 6] << 16 | + (uint32_t)msg[ 7] << 24; + + c = d = pad; + for(i = 8; i < len; i++) { + c <<= 8; + c |= msg[i]; + } + } else if (len >= 4) { + a = (uint32_t)msg[ 0] | + (uint32_t)msg[ 1] << 8 | + (uint32_t)msg[ 2] << 16 | + (uint32_t)msg[ 3] << 24; + + b = c = d = pad; + for(i = 4; i < len; i++) { + b <<= 8; + b |= msg[i]; + } + } else { + a = b = c = d = pad; + for(i = 0; i < len; i++) { + a <<= 8; + a |= msg[i]; + } + } + + TEACORE(FULLROUNDS); + + /* return 0; */ + return (h0 ^ h1); +} + +/* + * What follows in this file is copyright 2000 by Hans Reiser, and the + * licensing of what follows is governed by README + * */ +uint32_t +yura_hash(const signed char *msg, int len) +{ + int i; + int j, pow; + uint32_t a, c; + + for (pow = 1, i = 1; i < len; i++) + pow = pow * 10; + + if (len == 1) + a = msg[0] - 48; + else + a = (msg[0] - 48) * pow; + + for (i = 1; i < len; i++) { + c = msg[i] - 48; + for (pow = 1, j = i; j < len - 1; j++) + pow = pow * 10; + a = a + c * pow; + } + + for (; i < 40; i++) { + c = '0' - 48; + for (pow = 1, j = i; j < len - 1; j++) + pow = pow * 10; + a = a + c * pow; + } + + for (; i < 256; i++) { + c = i; + for (pow = 1, j = i; j < len - 1; j++) + pow = pow * 10; + a = a + c * pow; + } + + a = a << 7; + return (a); +} + +uint32_t +r5_hash(const signed char *msg, int len) +{ + uint32_t a; + const signed char *start; + + a = 0; + start = msg; + + while (*msg && msg < start + len) { + a += *msg << 4; + a += *msg >> 4; + a *= 11; + msg++; + } + + return (a); +} |
