Line data Source code
1 : // SPDX-License-Identifier: GPL-3.0-or-later
2 : // Copyright (C) 2013 Andrea Mazzoleni
3 :
4 : /*
5 : * Derivative work from SpookyV2.cpp/h
6 : *
7 : * WARNING!!!! Note that this implementation doesn't use the short hash optimization
8 : * resulting in different hashes for any length shorter than 192 bytes
9 : *
10 : * SpookyHash
11 : * http://burtleburtle.net/bob/hash/spooky.html
12 : *
13 : * Exact source used as reference:
14 : * http://burtleburtle.net/bob/c/SpookyV2.h
15 : * http://burtleburtle.net/bob/c/SpookyV2.cpp
16 : */
17 :
18 : // Spooky Hash
19 : // A 128-bit noncryptographic hash, for checksums and table lookup
20 : // By Bob Jenkins. Public domain.
21 : // Oct 31 2010: published framework, disclaimer ShortHash isn't right
22 : // Nov 7 2010: disabled ShortHash
23 : // Oct 31 2011: replace End, ShortMix, ShortEnd, enable ShortHash again
24 : // April 10 2012: buffer overflow on platforms without unaligned reads
25 : // July 12 2012: was passing out variables in final to in/out in short
26 : // July 30 2012: I reintroduced the buffer overflow
27 : // August 5 2012: SpookyV2: d = should be d += in short hash, and remove extra mix from long hash
28 : //
29 : // Up to 3 bytes/cycle for long messages. Reasonably fast for short messages.
30 : // All 1 or 2 bit deltas achieve avalanche within 1% bias per output bit.
31 : //
32 : // This was developed for and tested on 64-bit x86-compatible processors.
33 : // It assumes the processor is little-endian. There is a macro
34 : // controlling whether unaligned reads are allowed (by default they are).
35 : // This should be an equally good hash on big-endian machines, but it will
36 : // compute different results on them than on little-endian machines.
37 : //
38 : // Google's CityHash has similar specs to SpookyHash, and CityHash is faster
39 : // on new Intel boxes. MD4 and MD5 also have similar specs, but they are orders
40 : // of magnitude slower. CRCs are two or more times slower, but unlike
41 : // SpookyHash, they have nice math for combining the CRCs of pieces to form
42 : // the CRCs of wholes. There are also cryptographic hashes, but those are even
43 : // slower than MD5.
44 : //
45 :
46 : #define Mix(data, s0, s1, s2, s3, s4, s5, s6, s7, s8, s9, s10, s11) \
47 : s0 += data[0]; s2 ^= s10; s11 ^= s0; s0 = util_rotl64(s0, 11); s11 += s1; \
48 : s1 += data[1]; s3 ^= s11; s0 ^= s1; s1 = util_rotl64(s1, 32); s0 += s2; \
49 : s2 += data[2]; s4 ^= s0; s1 ^= s2; s2 = util_rotl64(s2, 43); s1 += s3; \
50 : s3 += data[3]; s5 ^= s1; s2 ^= s3; s3 = util_rotl64(s3, 31); s2 += s4; \
51 : s4 += data[4]; s6 ^= s2; s3 ^= s4; s4 = util_rotl64(s4, 17); s3 += s5; \
52 : s5 += data[5]; s7 ^= s3; s4 ^= s5; s5 = util_rotl64(s5, 28); s4 += s6; \
53 : s6 += data[6]; s8 ^= s4; s5 ^= s6; s6 = util_rotl64(s6, 39); s5 += s7; \
54 : s7 += data[7]; s9 ^= s5; s6 ^= s7; s7 = util_rotl64(s7, 57); s6 += s8; \
55 : s8 += data[8]; s10 ^= s6; s7 ^= s8; s8 = util_rotl64(s8, 55); s7 += s9; \
56 : s9 += data[9]; s11 ^= s7; s8 ^= s9; s9 = util_rotl64(s9, 54); s8 += s10; \
57 : s10 += data[10]; s0 ^= s8; s9 ^= s10; s10 = util_rotl64(s10, 22); s9 += s11; \
58 : s11 += data[11]; s1 ^= s9; s10 ^= s11; s11 = util_rotl64(s11, 46); s10 += s0;
59 :
60 : #define EndPartial(h0, h1, h2, h3, h4, h5, h6, h7, h8, h9, h10, h11) \
61 : h11 += h1; h2 ^= h11; h1 = util_rotl64(h1, 44); \
62 : h0 += h2; h3 ^= h0; h2 = util_rotl64(h2, 15); \
63 : h1 += h3; h4 ^= h1; h3 = util_rotl64(h3, 34); \
64 : h2 += h4; h5 ^= h2; h4 = util_rotl64(h4, 21); \
65 : h3 += h5; h6 ^= h3; h5 = util_rotl64(h5, 38); \
66 : h4 += h6; h7 ^= h4; h6 = util_rotl64(h6, 33); \
67 : h5 += h7; h8 ^= h5; h7 = util_rotl64(h7, 10); \
68 : h6 += h8; h9 ^= h6; h8 = util_rotl64(h8, 13); \
69 : h7 += h9; h10 ^= h7; h9 = util_rotl64(h9, 38); \
70 : h8 += h10; h11 ^= h8; h10 = util_rotl64(h10, 53); \
71 : h9 += h11; h0 ^= h9; h11 = util_rotl64(h11, 42); \
72 : h10 += h0; h1 ^= h10; h0 = util_rotl64(h0, 54);
73 :
74 : #define End(data, h0, h1, h2, h3, h4, h5, h6, h7, h8, h9, h10, h11) \
75 : h0 += data[0]; h1 += data[1]; h2 += data[2]; h3 += data[3]; \
76 : h4 += data[4]; h5 += data[5]; h6 += data[6]; h7 += data[7]; \
77 : h8 += data[8]; h9 += data[9]; h10 += data[10]; h11 += data[11]; \
78 : EndPartial(h0, h1, h2, h3, h4, h5, h6, h7, h8, h9, h10, h11); \
79 : EndPartial(h0, h1, h2, h3, h4, h5, h6, h7, h8, h9, h10, h11); \
80 : EndPartial(h0, h1, h2, h3, h4, h5, h6, h7, h8, h9, h10, h11);
81 :
82 : // number of uint64_t's in internal state
83 : #define sc_numVars 12
84 :
85 : // size of the internal state
86 : #define sc_blockSize (sc_numVars * 8)
87 :
88 : //
89 : // sc_const: a constant which:
90 : // * is not zero
91 : // * is odd
92 : // * is a not-very-regular mix of 1's and 0's
93 : // * does not need any other special mathematical properties
94 : //
95 : #define sc_const 0xdeadbeefdeadbeefLL
96 :
97 3928267 : void SpookyHash128(const void* data, size_t size, const uint8_t* seed, uint8_t* digest)
98 : {
99 : uint64_t h0, h1, h2, h3, h4, h5, h6, h7, h8, h9, h10, h11;
100 : uint64_t buf[sc_numVars];
101 : size_t nblocks;
102 : const uint64_t* blocks;
103 : const uint64_t* end;
104 : size_t size_remainder;
105 : #if WORDS_BIGENDIAN
106 : unsigned i;
107 : #endif
108 :
109 3928267 : h9 = util_read64(seed + 0);
110 3928267 : h10 = util_read64(seed + 8);
111 :
112 3928267 : h0 = h3 = h6 = h9;
113 3928267 : h1 = h4 = h7 = h10;
114 3928267 : h2 = h5 = h8 = h11 = sc_const;
115 :
116 3928267 : nblocks = size / sc_blockSize;
117 3928267 : blocks = data;
118 3928267 : end = blocks + nblocks * sc_numVars;
119 :
120 : /* body */
121 35961682 : while (blocks < end) {
122 : #if WORDS_BIGENDIAN
123 : for (i = 0; i < sc_numVars; ++i)
124 : buf[i] = util_swap64(blocks[i]);
125 : Mix(buf, h0, h1, h2, h3, h4, h5, h6, h7, h8, h9, h10, h11);
126 : #else
127 32033415 : Mix(blocks, h0, h1, h2, h3, h4, h5, h6, h7, h8, h9, h10, h11);
128 : #endif
129 32033415 : blocks += sc_numVars;
130 : }
131 :
132 : /* tail */
133 3928267 : size_remainder = (size - ((const uint8_t*)end - (const uint8_t*)data));
134 3928267 : memcpy(buf, end, size_remainder);
135 3928267 : memset(((uint8_t*)buf) + size_remainder, 0, sc_blockSize - size_remainder);
136 3928267 : ((uint8_t*)buf)[sc_blockSize - 1] = size_remainder;
137 :
138 : /* finalization */
139 : #if WORDS_BIGENDIAN
140 : for (i = 0; i < sc_numVars; ++i)
141 : buf[i] = util_swap64(buf[i]);
142 : #endif
143 3928267 : End(buf, h0, h1, h2, h3, h4, h5, h6, h7, h8, h9, h10, h11);
144 :
145 3928267 : util_write64(digest + 0, h0);
146 3928267 : util_write64(digest + 8, h1);
147 3928267 : }
148 :
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