diff options
Diffstat (limited to 'fs/ext3/hash.c')
| -rw-r--r-- | fs/ext3/hash.c | 206 |
1 files changed, 0 insertions, 206 deletions
diff --git a/fs/ext3/hash.c b/fs/ext3/hash.c deleted file mode 100644 index ede315c..0000000 --- a/fs/ext3/hash.c +++ /dev/null @@ -1,206 +0,0 @@ -/* - * linux/fs/ext3/hash.c - * - * Copyright (C) 2002 by Theodore Ts'o - * - * This file is released under the GPL v2. - * - * This file may be redistributed under the terms of the GNU Public - * License. - */ - -#include "ext3.h" -#include <linux/cryptohash.h> - -#define DELTA 0x9E3779B9 - -static void TEA_transform(__u32 buf[4], __u32 const in[]) -{ - __u32 sum = 0; - __u32 b0 = buf[0], b1 = buf[1]; - __u32 a = in[0], b = in[1], c = in[2], d = in[3]; - int n = 16; - - do { - sum += DELTA; - b0 += ((b1 << 4)+a) ^ (b1+sum) ^ ((b1 >> 5)+b); - b1 += ((b0 << 4)+c) ^ (b0+sum) ^ ((b0 >> 5)+d); - } while(--n); - - buf[0] += b0; - buf[1] += b1; -} - - -/* The old legacy hash */ -static __u32 dx_hack_hash_unsigned(const char *name, int len) -{ - __u32 hash, hash0 = 0x12a3fe2d, hash1 = 0x37abe8f9; - const unsigned char *ucp = (const unsigned char *) name; - - while (len--) { - hash = hash1 + (hash0 ^ (((int) *ucp++) * 7152373)); - - if (hash & 0x80000000) - hash -= 0x7fffffff; - hash1 = hash0; - hash0 = hash; - } - return hash0 << 1; -} - -static __u32 dx_hack_hash_signed(const char *name, int len) -{ - __u32 hash, hash0 = 0x12a3fe2d, hash1 = 0x37abe8f9; - const signed char *scp = (const signed char *) name; - - while (len--) { - hash = hash1 + (hash0 ^ (((int) *scp++) * 7152373)); - - if (hash & 0x80000000) - hash -= 0x7fffffff; - hash1 = hash0; - hash0 = hash; - } - return hash0 << 1; -} - -static void str2hashbuf_signed(const char *msg, int len, __u32 *buf, int num) -{ - __u32 pad, val; - int i; - const signed char *scp = (const signed char *) msg; - - pad = (__u32)len | ((__u32)len << 8); - pad |= pad << 16; - - val = pad; - if (len > num*4) - len = num * 4; - for (i = 0; i < len; i++) { - if ((i % 4) == 0) - val = pad; - val = ((int) scp[i]) + (val << 8); - if ((i % 4) == 3) { - *buf++ = val; - val = pad; - num--; - } - } - if (--num >= 0) - *buf++ = val; - while (--num >= 0) - *buf++ = pad; -} - -static void str2hashbuf_unsigned(const char *msg, int len, __u32 *buf, int num) -{ - __u32 pad, val; - int i; - const unsigned char *ucp = (const unsigned char *) msg; - - pad = (__u32)len | ((__u32)len << 8); - pad |= pad << 16; - - val = pad; - if (len > num*4) - len = num * 4; - for (i=0; i < len; i++) { - if ((i % 4) == 0) - val = pad; - val = ((int) ucp[i]) + (val << 8); - if ((i % 4) == 3) { - *buf++ = val; - val = pad; - num--; - } - } - if (--num >= 0) - *buf++ = val; - while (--num >= 0) - *buf++ = pad; -} - -/* - * Returns the hash of a filename. If len is 0 and name is NULL, then - * this function can be used to test whether or not a hash version is - * supported. - * - * The seed is an 4 longword (32 bits) "secret" which can be used to - * uniquify a hash. If the seed is all zero's, then some default seed - * may be used. - * - * A particular hash version specifies whether or not the seed is - * represented, and whether or not the returned hash is 32 bits or 64 - * bits. 32 bit hashes will return 0 for the minor hash. - */ -int ext3fs_dirhash(const char *name, int len, struct dx_hash_info *hinfo) -{ - __u32 hash; - __u32 minor_hash = 0; - const char *p; - int i; - __u32 in[8], buf[4]; - void (*str2hashbuf)(const char *, int, __u32 *, int) = - str2hashbuf_signed; - - /* Initialize the default seed for the hash checksum functions */ - buf[0] = 0x67452301; - buf[1] = 0xefcdab89; - buf[2] = 0x98badcfe; - buf[3] = 0x10325476; - - /* Check to see if the seed is all zero's */ - if (hinfo->seed) { - for (i=0; i < 4; i++) { - if (hinfo->seed[i]) - break; - } - if (i < 4) - memcpy(buf, hinfo->seed, sizeof(buf)); - } - - switch (hinfo->hash_version) { - case DX_HASH_LEGACY_UNSIGNED: - hash = dx_hack_hash_unsigned(name, len); - break; - case DX_HASH_LEGACY: - hash = dx_hack_hash_signed(name, len); - break; - case DX_HASH_HALF_MD4_UNSIGNED: - str2hashbuf = str2hashbuf_unsigned; - case DX_HASH_HALF_MD4: - p = name; - while (len > 0) { - (*str2hashbuf)(p, len, in, 8); - half_md4_transform(buf, in); - len -= 32; - p += 32; - } - minor_hash = buf[2]; - hash = buf[1]; - break; - case DX_HASH_TEA_UNSIGNED: - str2hashbuf = str2hashbuf_unsigned; - case DX_HASH_TEA: - p = name; - while (len > 0) { - (*str2hashbuf)(p, len, in, 4); - TEA_transform(buf, in); - len -= 16; - p += 16; - } - hash = buf[0]; - minor_hash = buf[1]; - break; - default: - hinfo->hash = 0; - return -1; - } - hash = hash & ~1; - if (hash == (EXT3_HTREE_EOF_32BIT << 1)) - hash = (EXT3_HTREE_EOF_32BIT - 1) << 1; - hinfo->hash = hash; - hinfo->minor_hash = minor_hash; - return 0; -} |
