1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/skia/trunk/src/utils/SkMD5.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,252 @@
1.4 +/*
1.5 + * Copyright 2012 Google Inc.
1.6 + *
1.7 + * Use of this source code is governed by a BSD-style license that can be
1.8 + * found in the LICENSE file.
1.9 + *
1.10 + * The following code is based on the description in RFC 1321.
1.11 + * http://www.ietf.org/rfc/rfc1321.txt
1.12 + */
1.13 +
1.14 +#include "SkTypes.h"
1.15 +#include "SkMD5.h"
1.16 +#include <string.h>
1.17 +
1.18 +/** MD5 basic transformation. Transforms state based on block. */
1.19 +static void transform(uint32_t state[4], const uint8_t block[64]);
1.20 +
1.21 +/** Encodes input into output (4 little endian 32 bit values). */
1.22 +static void encode(uint8_t output[16], const uint32_t input[4]);
1.23 +
1.24 +/** Encodes input into output (little endian 64 bit value). */
1.25 +static void encode(uint8_t output[8], const uint64_t input);
1.26 +
1.27 +/** Decodes input (4 little endian 32 bit values) into storage, if required. */
1.28 +static const uint32_t* decode(uint32_t storage[16], const uint8_t input[64]);
1.29 +
1.30 +SkMD5::SkMD5() : byteCount(0) {
1.31 + // These are magic numbers from the specification.
1.32 + this->state[0] = 0x67452301;
1.33 + this->state[1] = 0xefcdab89;
1.34 + this->state[2] = 0x98badcfe;
1.35 + this->state[3] = 0x10325476;
1.36 +}
1.37 +
1.38 +void SkMD5::update(const uint8_t* input, size_t inputLength) {
1.39 + unsigned int bufferIndex = (unsigned int)(this->byteCount & 0x3F);
1.40 + unsigned int bufferAvailable = 64 - bufferIndex;
1.41 +
1.42 + unsigned int inputIndex;
1.43 + if (inputLength >= bufferAvailable) {
1.44 + if (bufferIndex) {
1.45 + memcpy(&this->buffer[bufferIndex], input, bufferAvailable);
1.46 + transform(this->state, this->buffer);
1.47 + inputIndex = bufferAvailable;
1.48 + } else {
1.49 + inputIndex = 0;
1.50 + }
1.51 +
1.52 + for (; inputIndex + 63 < inputLength; inputIndex += 64) {
1.53 + transform(this->state, &input[inputIndex]);
1.54 + }
1.55 +
1.56 + bufferIndex = 0;
1.57 + } else {
1.58 + inputIndex = 0;
1.59 + }
1.60 +
1.61 + memcpy(&this->buffer[bufferIndex], &input[inputIndex], inputLength - inputIndex);
1.62 +
1.63 + this->byteCount += inputLength;
1.64 +}
1.65 +
1.66 +void SkMD5::finish(Digest& digest) {
1.67 + // Get the number of bits before padding.
1.68 + uint8_t bits[8];
1.69 + encode(bits, this->byteCount << 3);
1.70 +
1.71 + // Pad out to 56 mod 64.
1.72 + unsigned int bufferIndex = (unsigned int)(this->byteCount & 0x3F);
1.73 + unsigned int paddingLength = (bufferIndex < 56) ? (56 - bufferIndex) : (120 - bufferIndex);
1.74 + static uint8_t PADDING[64] = {
1.75 + 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
1.76 + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
1.77 + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
1.78 + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
1.79 + };
1.80 + this->update(PADDING, paddingLength);
1.81 +
1.82 + // Append length (length before padding, will cause final update).
1.83 + this->update(bits, 8);
1.84 +
1.85 + // Write out digest.
1.86 + encode(digest.data, this->state);
1.87 +
1.88 +#if defined(SK_MD5_CLEAR_DATA)
1.89 + // Clear state.
1.90 + memset(this, 0, sizeof(*this));
1.91 +#endif
1.92 +}
1.93 +
1.94 +struct F { uint32_t operator()(uint32_t x, uint32_t y, uint32_t z) {
1.95 + //return (x & y) | ((~x) & z);
1.96 + return ((y ^ z) & x) ^ z; //equivelent but faster
1.97 +}};
1.98 +
1.99 +struct G { uint32_t operator()(uint32_t x, uint32_t y, uint32_t z) {
1.100 + return (x & z) | (y & (~z));
1.101 + //return ((x ^ y) & z) ^ y; //equivelent but slower
1.102 +}};
1.103 +
1.104 +struct H { uint32_t operator()(uint32_t x, uint32_t y, uint32_t z) {
1.105 + return x ^ y ^ z;
1.106 +}};
1.107 +
1.108 +struct I { uint32_t operator()(uint32_t x, uint32_t y, uint32_t z) {
1.109 + return y ^ (x | (~z));
1.110 +}};
1.111 +
1.112 +/** Rotates x left n bits. */
1.113 +static inline uint32_t rotate_left(uint32_t x, uint8_t n) {
1.114 + return (x << n) | (x >> (32 - n));
1.115 +}
1.116 +
1.117 +template <typename T>
1.118 +static inline void operation(T operation, uint32_t& a, uint32_t b, uint32_t c, uint32_t d,
1.119 + uint32_t x, uint8_t s, uint32_t t) {
1.120 + a = b + rotate_left(a + operation(b, c, d) + x + t, s);
1.121 +}
1.122 +
1.123 +static void transform(uint32_t state[4], const uint8_t block[64]) {
1.124 + uint32_t a = state[0], b = state[1], c = state[2], d = state[3];
1.125 +
1.126 + uint32_t storage[16];
1.127 + const uint32_t* X = decode(storage, block);
1.128 +
1.129 + // Round 1
1.130 + operation(F(), a, b, c, d, X[ 0], 7, 0xd76aa478); // 1
1.131 + operation(F(), d, a, b, c, X[ 1], 12, 0xe8c7b756); // 2
1.132 + operation(F(), c, d, a, b, X[ 2], 17, 0x242070db); // 3
1.133 + operation(F(), b, c, d, a, X[ 3], 22, 0xc1bdceee); // 4
1.134 + operation(F(), a, b, c, d, X[ 4], 7, 0xf57c0faf); // 5
1.135 + operation(F(), d, a, b, c, X[ 5], 12, 0x4787c62a); // 6
1.136 + operation(F(), c, d, a, b, X[ 6], 17, 0xa8304613); // 7
1.137 + operation(F(), b, c, d, a, X[ 7], 22, 0xfd469501); // 8
1.138 + operation(F(), a, b, c, d, X[ 8], 7, 0x698098d8); // 9
1.139 + operation(F(), d, a, b, c, X[ 9], 12, 0x8b44f7af); // 10
1.140 + operation(F(), c, d, a, b, X[10], 17, 0xffff5bb1); // 11
1.141 + operation(F(), b, c, d, a, X[11], 22, 0x895cd7be); // 12
1.142 + operation(F(), a, b, c, d, X[12], 7, 0x6b901122); // 13
1.143 + operation(F(), d, a, b, c, X[13], 12, 0xfd987193); // 14
1.144 + operation(F(), c, d, a, b, X[14], 17, 0xa679438e); // 15
1.145 + operation(F(), b, c, d, a, X[15], 22, 0x49b40821); // 16
1.146 +
1.147 + // Round 2
1.148 + operation(G(), a, b, c, d, X[ 1], 5, 0xf61e2562); // 17
1.149 + operation(G(), d, a, b, c, X[ 6], 9, 0xc040b340); // 18
1.150 + operation(G(), c, d, a, b, X[11], 14, 0x265e5a51); // 19
1.151 + operation(G(), b, c, d, a, X[ 0], 20, 0xe9b6c7aa); // 20
1.152 + operation(G(), a, b, c, d, X[ 5], 5, 0xd62f105d); // 21
1.153 + operation(G(), d, a, b, c, X[10], 9, 0x2441453); // 22
1.154 + operation(G(), c, d, a, b, X[15], 14, 0xd8a1e681); // 23
1.155 + operation(G(), b, c, d, a, X[ 4], 20, 0xe7d3fbc8); // 24
1.156 + operation(G(), a, b, c, d, X[ 9], 5, 0x21e1cde6); // 25
1.157 + operation(G(), d, a, b, c, X[14], 9, 0xc33707d6); // 26
1.158 + operation(G(), c, d, a, b, X[ 3], 14, 0xf4d50d87); // 27
1.159 + operation(G(), b, c, d, a, X[ 8], 20, 0x455a14ed); // 28
1.160 + operation(G(), a, b, c, d, X[13], 5, 0xa9e3e905); // 29
1.161 + operation(G(), d, a, b, c, X[ 2], 9, 0xfcefa3f8); // 30
1.162 + operation(G(), c, d, a, b, X[ 7], 14, 0x676f02d9); // 31
1.163 + operation(G(), b, c, d, a, X[12], 20, 0x8d2a4c8a); // 32
1.164 +
1.165 + // Round 3
1.166 + operation(H(), a, b, c, d, X[ 5], 4, 0xfffa3942); // 33
1.167 + operation(H(), d, a, b, c, X[ 8], 11, 0x8771f681); // 34
1.168 + operation(H(), c, d, a, b, X[11], 16, 0x6d9d6122); // 35
1.169 + operation(H(), b, c, d, a, X[14], 23, 0xfde5380c); // 36
1.170 + operation(H(), a, b, c, d, X[ 1], 4, 0xa4beea44); // 37
1.171 + operation(H(), d, a, b, c, X[ 4], 11, 0x4bdecfa9); // 38
1.172 + operation(H(), c, d, a, b, X[ 7], 16, 0xf6bb4b60); // 39
1.173 + operation(H(), b, c, d, a, X[10], 23, 0xbebfbc70); // 40
1.174 + operation(H(), a, b, c, d, X[13], 4, 0x289b7ec6); // 41
1.175 + operation(H(), d, a, b, c, X[ 0], 11, 0xeaa127fa); // 42
1.176 + operation(H(), c, d, a, b, X[ 3], 16, 0xd4ef3085); // 43
1.177 + operation(H(), b, c, d, a, X[ 6], 23, 0x4881d05); // 44
1.178 + operation(H(), a, b, c, d, X[ 9], 4, 0xd9d4d039); // 45
1.179 + operation(H(), d, a, b, c, X[12], 11, 0xe6db99e5); // 46
1.180 + operation(H(), c, d, a, b, X[15], 16, 0x1fa27cf8); // 47
1.181 + operation(H(), b, c, d, a, X[ 2], 23, 0xc4ac5665); // 48
1.182 +
1.183 + // Round 4
1.184 + operation(I(), a, b, c, d, X[ 0], 6, 0xf4292244); // 49
1.185 + operation(I(), d, a, b, c, X[ 7], 10, 0x432aff97); // 50
1.186 + operation(I(), c, d, a, b, X[14], 15, 0xab9423a7); // 51
1.187 + operation(I(), b, c, d, a, X[ 5], 21, 0xfc93a039); // 52
1.188 + operation(I(), a, b, c, d, X[12], 6, 0x655b59c3); // 53
1.189 + operation(I(), d, a, b, c, X[ 3], 10, 0x8f0ccc92); // 54
1.190 + operation(I(), c, d, a, b, X[10], 15, 0xffeff47d); // 55
1.191 + operation(I(), b, c, d, a, X[ 1], 21, 0x85845dd1); // 56
1.192 + operation(I(), a, b, c, d, X[ 8], 6, 0x6fa87e4f); // 57
1.193 + operation(I(), d, a, b, c, X[15], 10, 0xfe2ce6e0); // 58
1.194 + operation(I(), c, d, a, b, X[ 6], 15, 0xa3014314); // 59
1.195 + operation(I(), b, c, d, a, X[13], 21, 0x4e0811a1); // 60
1.196 + operation(I(), a, b, c, d, X[ 4], 6, 0xf7537e82); // 61
1.197 + operation(I(), d, a, b, c, X[11], 10, 0xbd3af235); // 62
1.198 + operation(I(), c, d, a, b, X[ 2], 15, 0x2ad7d2bb); // 63
1.199 + operation(I(), b, c, d, a, X[ 9], 21, 0xeb86d391); // 64
1.200 +
1.201 + state[0] += a;
1.202 + state[1] += b;
1.203 + state[2] += c;
1.204 + state[3] += d;
1.205 +
1.206 +#if defined(SK_MD5_CLEAR_DATA)
1.207 + // Clear sensitive information.
1.208 + if (X == &storage) {
1.209 + memset(storage, 0, sizeof(storage));
1.210 + }
1.211 +#endif
1.212 +}
1.213 +
1.214 +static void encode(uint8_t output[16], const uint32_t input[4]) {
1.215 + for (size_t i = 0, j = 0; i < 4; i++, j += 4) {
1.216 + output[j ] = (uint8_t) (input[i] & 0xff);
1.217 + output[j+1] = (uint8_t)((input[i] >> 8) & 0xff);
1.218 + output[j+2] = (uint8_t)((input[i] >> 16) & 0xff);
1.219 + output[j+3] = (uint8_t)((input[i] >> 24) & 0xff);
1.220 + }
1.221 +}
1.222 +
1.223 +static void encode(uint8_t output[8], const uint64_t input) {
1.224 + output[0] = (uint8_t) (input & 0xff);
1.225 + output[1] = (uint8_t)((input >> 8) & 0xff);
1.226 + output[2] = (uint8_t)((input >> 16) & 0xff);
1.227 + output[3] = (uint8_t)((input >> 24) & 0xff);
1.228 + output[4] = (uint8_t)((input >> 32) & 0xff);
1.229 + output[5] = (uint8_t)((input >> 40) & 0xff);
1.230 + output[6] = (uint8_t)((input >> 48) & 0xff);
1.231 + output[7] = (uint8_t)((input >> 56) & 0xff);
1.232 +}
1.233 +
1.234 +static inline bool is_aligned(const void *pointer, size_t byte_count) {
1.235 + return reinterpret_cast<uintptr_t>(pointer) % byte_count == 0;
1.236 +}
1.237 +
1.238 +static const uint32_t* decode(uint32_t storage[16], const uint8_t input[64]) {
1.239 +#if defined(SK_CPU_LENDIAN) && defined(SK_CPU_FAST_UNALIGNED_ACCESS)
1.240 + return reinterpret_cast<const uint32_t*>(input);
1.241 +#else
1.242 +#if defined(SK_CPU_LENDIAN)
1.243 + if (is_aligned(input, 4)) {
1.244 + return reinterpret_cast<const uint32_t*>(input);
1.245 + }
1.246 +#endif
1.247 + for (size_t i = 0, j = 0; j < 64; i++, j += 4) {
1.248 + storage[i] = ((uint32_t)input[j ]) |
1.249 + (((uint32_t)input[j+1]) << 8) |
1.250 + (((uint32_t)input[j+2]) << 16) |
1.251 + (((uint32_t)input[j+3]) << 24);
1.252 + }
1.253 + return storage;
1.254 +#endif
1.255 +}
