Blame view
fs/ext4/hash.c
7.27 KB
f51667685 ext4: fix up rema... |
1 |
// SPDX-License-Identifier: GPL-2.0 |
ac27a0ec1 [PATCH] ext4: ini... |
2 |
/* |
617ba13b3 [PATCH] ext4: ren... |
3 |
* linux/fs/ext4/hash.c |
ac27a0ec1 [PATCH] ext4: ini... |
4 5 |
* * Copyright (C) 2002 by Theodore Ts'o |
ac27a0ec1 [PATCH] ext4: ini... |
6 7 8 |
*/ #include <linux/fs.h> |
b886ee3e7 ext4: Support cas... |
9 |
#include <linux/unicode.h> |
1c83a9aab ext4: move halfmd... |
10 11 |
#include <linux/compiler.h> #include <linux/bitops.h> |
3dcf54515 ext4: move header... |
12 |
#include "ext4.h" |
ac27a0ec1 [PATCH] ext4: ini... |
13 14 15 16 17 18 19 20 21 22 23 24 25 26 |
#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); |
af5bc92dd ext4: Fix whitesp... |
27 |
} while (--n); |
ac27a0ec1 [PATCH] ext4: ini... |
28 29 30 31 |
buf[0] += b0; buf[1] += b1; } |
1c83a9aab ext4: move halfmd... |
32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 |
/* F, G and H are basic MD4 functions: selection, majority, parity */ #define F(x, y, z) ((z) ^ ((x) & ((y) ^ (z)))) #define G(x, y, z) (((x) & (y)) + (((x) ^ (y)) & (z))) #define H(x, y, z) ((x) ^ (y) ^ (z)) /* * The generic round function. The application is so specific that * we don't bother protecting all the arguments with parens, as is generally * good macro practice, in favor of extra legibility. * Rotation is separate from addition to prevent recomputation */ #define ROUND(f, a, b, c, d, x, s) \ (a += f(b, c, d) + x, a = rol32(a, s)) #define K1 0 #define K2 013240474631UL #define K3 015666365641UL /* * Basic cut-down MD4 transform. Returns only 32 bits of result. */ static __u32 half_md4_transform(__u32 buf[4], __u32 const in[8]) { __u32 a = buf[0], b = buf[1], c = buf[2], d = buf[3]; /* Round 1 */ ROUND(F, a, b, c, d, in[0] + K1, 3); ROUND(F, d, a, b, c, in[1] + K1, 7); ROUND(F, c, d, a, b, in[2] + K1, 11); ROUND(F, b, c, d, a, in[3] + K1, 19); ROUND(F, a, b, c, d, in[4] + K1, 3); ROUND(F, d, a, b, c, in[5] + K1, 7); ROUND(F, c, d, a, b, in[6] + K1, 11); ROUND(F, b, c, d, a, in[7] + K1, 19); /* Round 2 */ ROUND(G, a, b, c, d, in[1] + K2, 3); ROUND(G, d, a, b, c, in[3] + K2, 5); ROUND(G, c, d, a, b, in[5] + K2, 9); ROUND(G, b, c, d, a, in[7] + K2, 13); ROUND(G, a, b, c, d, in[0] + K2, 3); ROUND(G, d, a, b, c, in[2] + K2, 5); ROUND(G, c, d, a, b, in[4] + K2, 9); ROUND(G, b, c, d, a, in[6] + K2, 13); /* Round 3 */ ROUND(H, a, b, c, d, in[3] + K3, 3); ROUND(H, d, a, b, c, in[7] + K3, 9); ROUND(H, c, d, a, b, in[2] + K3, 11); ROUND(H, b, c, d, a, in[6] + K3, 15); ROUND(H, a, b, c, d, in[1] + K3, 3); ROUND(H, d, a, b, c, in[5] + K3, 9); ROUND(H, c, d, a, b, in[0] + K3, 11); ROUND(H, b, c, d, a, in[4] + K3, 15); buf[0] += a; buf[1] += b; buf[2] += c; buf[3] += d; return buf[1]; /* "most hashed" word */ } #undef ROUND #undef K1 #undef K2 #undef K3 #undef F #undef G #undef H |
ac27a0ec1 [PATCH] ext4: ini... |
100 101 |
/* The old legacy hash */ |
f99b25897 ext4: Add support... |
102 |
static __u32 dx_hack_hash_unsigned(const char *name, int len) |
ac27a0ec1 [PATCH] ext4: ini... |
103 |
{ |
f99b25897 ext4: Add support... |
104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 |
__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; |
ac27a0ec1 [PATCH] ext4: ini... |
122 |
while (len--) { |
f99b25897 ext4: Add support... |
123 |
hash = hash1 + (hash0 ^ (((int) *scp++) * 7152373)); |
ac27a0ec1 [PATCH] ext4: ini... |
124 |
|
f99b25897 ext4: Add support... |
125 126 |
if (hash & 0x80000000) hash -= 0x7fffffff; |
ac27a0ec1 [PATCH] ext4: ini... |
127 128 129 |
hash1 = hash0; hash0 = hash; } |
f99b25897 ext4: Add support... |
130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 |
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++) { |
f99b25897 ext4: Add support... |
146 147 148 149 150 151 152 153 154 155 156 |
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; |
ac27a0ec1 [PATCH] ext4: ini... |
157 |
} |
f99b25897 ext4: Add support... |
158 |
static void str2hashbuf_unsigned(const char *msg, int len, __u32 *buf, int num) |
ac27a0ec1 [PATCH] ext4: ini... |
159 160 161 |
{ __u32 pad, val; int i; |
f99b25897 ext4: Add support... |
162 |
const unsigned char *ucp = (const unsigned char *) msg; |
ac27a0ec1 [PATCH] ext4: ini... |
163 164 165 166 167 168 169 |
pad = (__u32)len | ((__u32)len << 8); pad |= pad << 16; val = pad; if (len > num*4) len = num * 4; |
af5bc92dd ext4: Fix whitesp... |
170 |
for (i = 0; i < len; i++) { |
f99b25897 ext4: Add support... |
171 |
val = ((int) ucp[i]) + (val << 8); |
ac27a0ec1 [PATCH] ext4: ini... |
172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 |
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. */ |
705a3e5b1 ANDROID: ext4: Ha... |
197 |
static int __ext4fs_dirhash(const struct inode *dir, const char *name, int len, |
b886ee3e7 ext4: Support cas... |
198 |
struct dx_hash_info *hinfo) |
ac27a0ec1 [PATCH] ext4: ini... |
199 200 201 202 203 204 |
{ __u32 hash; __u32 minor_hash = 0; const char *p; int i; __u32 in[8], buf[4]; |
f99b25897 ext4: Add support... |
205 206 |
void (*str2hashbuf)(const char *, int, __u32 *, int) = str2hashbuf_signed; |
ac27a0ec1 [PATCH] ext4: ini... |
207 208 209 210 211 212 213 214 215 |
/* 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) { |
af5bc92dd ext4: Fix whitesp... |
216 |
for (i = 0; i < 4; i++) { |
0e79537d3 ext4: reduce one ... |
217 218 |
if (hinfo->seed[i]) { memcpy(buf, hinfo->seed, sizeof(buf)); |
ac27a0ec1 [PATCH] ext4: ini... |
219 |
break; |
0e79537d3 ext4: reduce one ... |
220 |
} |
ac27a0ec1 [PATCH] ext4: ini... |
221 |
} |
ac27a0ec1 [PATCH] ext4: ini... |
222 223 224 |
} switch (hinfo->hash_version) { |
f99b25897 ext4: Add support... |
225 226 227 |
case DX_HASH_LEGACY_UNSIGNED: hash = dx_hack_hash_unsigned(name, len); break; |
ac27a0ec1 [PATCH] ext4: ini... |
228 |
case DX_HASH_LEGACY: |
f99b25897 ext4: Add support... |
229 |
hash = dx_hack_hash_signed(name, len); |
ac27a0ec1 [PATCH] ext4: ini... |
230 |
break; |
f99b25897 ext4: Add support... |
231 232 |
case DX_HASH_HALF_MD4_UNSIGNED: str2hashbuf = str2hashbuf_unsigned; |
70d7ced2e ext4: change to u... |
233 |
fallthrough; |
ac27a0ec1 [PATCH] ext4: ini... |
234 235 236 |
case DX_HASH_HALF_MD4: p = name; while (len > 0) { |
f99b25897 ext4: Add support... |
237 |
(*str2hashbuf)(p, len, in, 8); |
ac27a0ec1 [PATCH] ext4: ini... |
238 239 240 241 242 243 244 |
half_md4_transform(buf, in); len -= 32; p += 32; } minor_hash = buf[2]; hash = buf[1]; break; |
f99b25897 ext4: Add support... |
245 246 |
case DX_HASH_TEA_UNSIGNED: str2hashbuf = str2hashbuf_unsigned; |
70d7ced2e ext4: change to u... |
247 |
fallthrough; |
ac27a0ec1 [PATCH] ext4: ini... |
248 249 250 |
case DX_HASH_TEA: p = name; while (len > 0) { |
f99b25897 ext4: Add support... |
251 |
(*str2hashbuf)(p, len, in, 4); |
ac27a0ec1 [PATCH] ext4: ini... |
252 253 254 255 256 257 258 |
TEA_transform(buf, in); len -= 16; p += 16; } hash = buf[0]; minor_hash = buf[1]; break; |
705a3e5b1 ANDROID: ext4: Ha... |
259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 |
case DX_HASH_SIPHASH: { struct qstr qname = QSTR_INIT(name, len); __u64 combined_hash; if (fscrypt_has_encryption_key(dir)) { combined_hash = fscrypt_fname_siphash(dir, &qname); } else { ext4_warning_inode(dir, "Siphash requires key"); return -1; } hash = (__u32)(combined_hash >> 32); minor_hash = (__u32)combined_hash; break; } |
ac27a0ec1 [PATCH] ext4: ini... |
275 276 277 278 279 |
default: hinfo->hash = 0; return -1; } hash = hash & ~1; |
d1f5273e9 ext4: return 32/6... |
280 281 |
if (hash == (EXT4_HTREE_EOF_32BIT << 1)) hash = (EXT4_HTREE_EOF_32BIT - 1) << 1; |
ac27a0ec1 [PATCH] ext4: ini... |
282 283 284 285 |
hinfo->hash = hash; hinfo->minor_hash = minor_hash; return 0; } |
b886ee3e7 ext4: Support cas... |
286 287 288 289 290 |
int ext4fs_dirhash(const struct inode *dir, const char *name, int len, struct dx_hash_info *hinfo) { #ifdef CONFIG_UNICODE |
8b67e802e FROMLIST: ext4: U... |
291 |
const struct unicode_map *um = dir->i_sb->s_encoding; |
b886ee3e7 ext4: Support cas... |
292 293 294 |
int r, dlen; unsigned char *buff; struct qstr qstr = {.name = name, .len = len }; |
4358dcf4e ANDROID: ext4: fi... |
295 296 |
if (len && IS_CASEFOLDED(dir) && um && (!IS_ENCRYPTED(dir) || fscrypt_has_encryption_key(dir))) { |
b886ee3e7 ext4: Support cas... |
297 298 299 300 301 302 303 304 305 |
buff = kzalloc(sizeof(char) * PATH_MAX, GFP_KERNEL); if (!buff) return -ENOMEM; dlen = utf8_casefold(um, &qstr, buff, PATH_MAX); if (dlen < 0) { kfree(buff); goto opaque_seq; } |
705a3e5b1 ANDROID: ext4: Ha... |
306 |
r = __ext4fs_dirhash(dir, buff, dlen, hinfo); |
b886ee3e7 ext4: Support cas... |
307 308 309 310 311 312 |
kfree(buff); return r; } opaque_seq: #endif |
705a3e5b1 ANDROID: ext4: Ha... |
313 |
return __ext4fs_dirhash(dir, name, len, hinfo); |
b886ee3e7 ext4: Support cas... |
314 |
} |