diff options
Diffstat (limited to 'fs/ext4/hash.c')
-rw-r--r-- | fs/ext4/hash.c | 77 |
1 files changed, 67 insertions, 10 deletions
diff --git a/fs/ext4/hash.c b/fs/ext4/hash.c index 556ca8eba3db..ac8f168c8ab4 100644 --- a/fs/ext4/hash.c +++ b/fs/ext4/hash.c | |||
@@ -35,23 +35,71 @@ static void TEA_transform(__u32 buf[4], __u32 const in[]) | |||
35 | 35 | ||
36 | 36 | ||
37 | /* The old legacy hash */ | 37 | /* The old legacy hash */ |
38 | static __u32 dx_hack_hash(const char *name, int len) | 38 | static __u32 dx_hack_hash_unsigned(const char *name, int len) |
39 | { | 39 | { |
40 | __u32 hash0 = 0x12a3fe2d, hash1 = 0x37abe8f9; | 40 | __u32 hash, hash0 = 0x12a3fe2d, hash1 = 0x37abe8f9; |
41 | const unsigned char *ucp = (const unsigned char *) name; | ||
42 | |||
43 | while (len--) { | ||
44 | hash = hash1 + (hash0 ^ (((int) *ucp++) * 7152373)); | ||
45 | |||
46 | if (hash & 0x80000000) | ||
47 | hash -= 0x7fffffff; | ||
48 | hash1 = hash0; | ||
49 | hash0 = hash; | ||
50 | } | ||
51 | return hash0 << 1; | ||
52 | } | ||
53 | |||
54 | static __u32 dx_hack_hash_signed(const char *name, int len) | ||
55 | { | ||
56 | __u32 hash, hash0 = 0x12a3fe2d, hash1 = 0x37abe8f9; | ||
57 | const signed char *scp = (const signed char *) name; | ||
58 | |||
41 | while (len--) { | 59 | while (len--) { |
42 | __u32 hash = hash1 + (hash0 ^ (*name++ * 7152373)); | 60 | hash = hash1 + (hash0 ^ (((int) *scp++) * 7152373)); |
43 | 61 | ||
44 | if (hash & 0x80000000) hash -= 0x7fffffff; | 62 | if (hash & 0x80000000) |
63 | hash -= 0x7fffffff; | ||
45 | hash1 = hash0; | 64 | hash1 = hash0; |
46 | hash0 = hash; | 65 | hash0 = hash; |
47 | } | 66 | } |
48 | return (hash0 << 1); | 67 | return hash0 << 1; |
68 | } | ||
69 | |||
70 | static void str2hashbuf_signed(const char *msg, int len, __u32 *buf, int num) | ||
71 | { | ||
72 | __u32 pad, val; | ||
73 | int i; | ||
74 | const signed char *scp = (const signed char *) msg; | ||
75 | |||
76 | pad = (__u32)len | ((__u32)len << 8); | ||
77 | pad |= pad << 16; | ||
78 | |||
79 | val = pad; | ||
80 | if (len > num*4) | ||
81 | len = num * 4; | ||
82 | for (i = 0; i < len; i++) { | ||
83 | if ((i % 4) == 0) | ||
84 | val = pad; | ||
85 | val = ((int) scp[i]) + (val << 8); | ||
86 | if ((i % 4) == 3) { | ||
87 | *buf++ = val; | ||
88 | val = pad; | ||
89 | num--; | ||
90 | } | ||
91 | } | ||
92 | if (--num >= 0) | ||
93 | *buf++ = val; | ||
94 | while (--num >= 0) | ||
95 | *buf++ = pad; | ||
49 | } | 96 | } |
50 | 97 | ||
51 | static void str2hashbuf(const char *msg, int len, __u32 *buf, int num) | 98 | static void str2hashbuf_unsigned(const char *msg, int len, __u32 *buf, int num) |
52 | { | 99 | { |
53 | __u32 pad, val; | 100 | __u32 pad, val; |
54 | int i; | 101 | int i; |
102 | const unsigned char *ucp = (const unsigned char *) msg; | ||
55 | 103 | ||
56 | pad = (__u32)len | ((__u32)len << 8); | 104 | pad = (__u32)len | ((__u32)len << 8); |
57 | pad |= pad << 16; | 105 | pad |= pad << 16; |
@@ -62,7 +110,7 @@ static void str2hashbuf(const char *msg, int len, __u32 *buf, int num) | |||
62 | for (i = 0; i < len; i++) { | 110 | for (i = 0; i < len; i++) { |
63 | if ((i % 4) == 0) | 111 | if ((i % 4) == 0) |
64 | val = pad; | 112 | val = pad; |
65 | val = msg[i] + (val << 8); | 113 | val = ((int) ucp[i]) + (val << 8); |
66 | if ((i % 4) == 3) { | 114 | if ((i % 4) == 3) { |
67 | *buf++ = val; | 115 | *buf++ = val; |
68 | val = pad; | 116 | val = pad; |
@@ -95,6 +143,8 @@ int ext4fs_dirhash(const char *name, int len, struct dx_hash_info *hinfo) | |||
95 | const char *p; | 143 | const char *p; |
96 | int i; | 144 | int i; |
97 | __u32 in[8], buf[4]; | 145 | __u32 in[8], buf[4]; |
146 | void (*str2hashbuf)(const char *, int, __u32 *, int) = | ||
147 | str2hashbuf_signed; | ||
98 | 148 | ||
99 | /* Initialize the default seed for the hash checksum functions */ | 149 | /* Initialize the default seed for the hash checksum functions */ |
100 | buf[0] = 0x67452301; | 150 | buf[0] = 0x67452301; |
@@ -113,13 +163,18 @@ int ext4fs_dirhash(const char *name, int len, struct dx_hash_info *hinfo) | |||
113 | } | 163 | } |
114 | 164 | ||
115 | switch (hinfo->hash_version) { | 165 | switch (hinfo->hash_version) { |
166 | case DX_HASH_LEGACY_UNSIGNED: | ||
167 | hash = dx_hack_hash_unsigned(name, len); | ||
168 | break; | ||
116 | case DX_HASH_LEGACY: | 169 | case DX_HASH_LEGACY: |
117 | hash = dx_hack_hash(name, len); | 170 | hash = dx_hack_hash_signed(name, len); |
118 | break; | 171 | break; |
172 | case DX_HASH_HALF_MD4_UNSIGNED: | ||
173 | str2hashbuf = str2hashbuf_unsigned; | ||
119 | case DX_HASH_HALF_MD4: | 174 | case DX_HASH_HALF_MD4: |
120 | p = name; | 175 | p = name; |
121 | while (len > 0) { | 176 | while (len > 0) { |
122 | str2hashbuf(p, len, in, 8); | 177 | (*str2hashbuf)(p, len, in, 8); |
123 | half_md4_transform(buf, in); | 178 | half_md4_transform(buf, in); |
124 | len -= 32; | 179 | len -= 32; |
125 | p += 32; | 180 | p += 32; |
@@ -127,10 +182,12 @@ int ext4fs_dirhash(const char *name, int len, struct dx_hash_info *hinfo) | |||
127 | minor_hash = buf[2]; | 182 | minor_hash = buf[2]; |
128 | hash = buf[1]; | 183 | hash = buf[1]; |
129 | break; | 184 | break; |
185 | case DX_HASH_TEA_UNSIGNED: | ||
186 | str2hashbuf = str2hashbuf_unsigned; | ||
130 | case DX_HASH_TEA: | 187 | case DX_HASH_TEA: |
131 | p = name; | 188 | p = name; |
132 | while (len > 0) { | 189 | while (len > 0) { |
133 | str2hashbuf(p, len, in, 4); | 190 | (*str2hashbuf)(p, len, in, 4); |
134 | TEA_transform(buf, in); | 191 | TEA_transform(buf, in); |
135 | len -= 16; | 192 | len -= 16; |
136 | p += 16; | 193 | p += 16; |