diff -r 000000000000 -r 6474c204b198 gfx/skia/trunk/src/utils/SkMD5.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/gfx/skia/trunk/src/utils/SkMD5.cpp Wed Dec 31 06:09:35 2014 +0100 @@ -0,0 +1,252 @@ +/* + * Copyright 2012 Google Inc. + * + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + * + * The following code is based on the description in RFC 1321. + * http://www.ietf.org/rfc/rfc1321.txt + */ + +#include "SkTypes.h" +#include "SkMD5.h" +#include + +/** MD5 basic transformation. Transforms state based on block. */ +static void transform(uint32_t state[4], const uint8_t block[64]); + +/** Encodes input into output (4 little endian 32 bit values). */ +static void encode(uint8_t output[16], const uint32_t input[4]); + +/** Encodes input into output (little endian 64 bit value). */ +static void encode(uint8_t output[8], const uint64_t input); + +/** Decodes input (4 little endian 32 bit values) into storage, if required. */ +static const uint32_t* decode(uint32_t storage[16], const uint8_t input[64]); + +SkMD5::SkMD5() : byteCount(0) { + // These are magic numbers from the specification. + this->state[0] = 0x67452301; + this->state[1] = 0xefcdab89; + this->state[2] = 0x98badcfe; + this->state[3] = 0x10325476; +} + +void SkMD5::update(const uint8_t* input, size_t inputLength) { + unsigned int bufferIndex = (unsigned int)(this->byteCount & 0x3F); + unsigned int bufferAvailable = 64 - bufferIndex; + + unsigned int inputIndex; + if (inputLength >= bufferAvailable) { + if (bufferIndex) { + memcpy(&this->buffer[bufferIndex], input, bufferAvailable); + transform(this->state, this->buffer); + inputIndex = bufferAvailable; + } else { + inputIndex = 0; + } + + for (; inputIndex + 63 < inputLength; inputIndex += 64) { + transform(this->state, &input[inputIndex]); + } + + bufferIndex = 0; + } else { + inputIndex = 0; + } + + memcpy(&this->buffer[bufferIndex], &input[inputIndex], inputLength - inputIndex); + + this->byteCount += inputLength; +} + +void SkMD5::finish(Digest& digest) { + // Get the number of bits before padding. + uint8_t bits[8]; + encode(bits, this->byteCount << 3); + + // Pad out to 56 mod 64. + unsigned int bufferIndex = (unsigned int)(this->byteCount & 0x3F); + unsigned int paddingLength = (bufferIndex < 56) ? (56 - bufferIndex) : (120 - bufferIndex); + static uint8_t PADDING[64] = { + 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + }; + this->update(PADDING, paddingLength); + + // Append length (length before padding, will cause final update). + this->update(bits, 8); + + // Write out digest. + encode(digest.data, this->state); + +#if defined(SK_MD5_CLEAR_DATA) + // Clear state. + memset(this, 0, sizeof(*this)); +#endif +} + +struct F { uint32_t operator()(uint32_t x, uint32_t y, uint32_t z) { + //return (x & y) | ((~x) & z); + return ((y ^ z) & x) ^ z; //equivelent but faster +}}; + +struct G { uint32_t operator()(uint32_t x, uint32_t y, uint32_t z) { + return (x & z) | (y & (~z)); + //return ((x ^ y) & z) ^ y; //equivelent but slower +}}; + +struct H { uint32_t operator()(uint32_t x, uint32_t y, uint32_t z) { + return x ^ y ^ z; +}}; + +struct I { uint32_t operator()(uint32_t x, uint32_t y, uint32_t z) { + return y ^ (x | (~z)); +}}; + +/** Rotates x left n bits. */ +static inline uint32_t rotate_left(uint32_t x, uint8_t n) { + return (x << n) | (x >> (32 - n)); +} + +template +static inline void operation(T operation, uint32_t& a, uint32_t b, uint32_t c, uint32_t d, + uint32_t x, uint8_t s, uint32_t t) { + a = b + rotate_left(a + operation(b, c, d) + x + t, s); +} + +static void transform(uint32_t state[4], const uint8_t block[64]) { + uint32_t a = state[0], b = state[1], c = state[2], d = state[3]; + + uint32_t storage[16]; + const uint32_t* X = decode(storage, block); + + // Round 1 + operation(F(), a, b, c, d, X[ 0], 7, 0xd76aa478); // 1 + operation(F(), d, a, b, c, X[ 1], 12, 0xe8c7b756); // 2 + operation(F(), c, d, a, b, X[ 2], 17, 0x242070db); // 3 + operation(F(), b, c, d, a, X[ 3], 22, 0xc1bdceee); // 4 + operation(F(), a, b, c, d, X[ 4], 7, 0xf57c0faf); // 5 + operation(F(), d, a, b, c, X[ 5], 12, 0x4787c62a); // 6 + operation(F(), c, d, a, b, X[ 6], 17, 0xa8304613); // 7 + operation(F(), b, c, d, a, X[ 7], 22, 0xfd469501); // 8 + operation(F(), a, b, c, d, X[ 8], 7, 0x698098d8); // 9 + operation(F(), d, a, b, c, X[ 9], 12, 0x8b44f7af); // 10 + operation(F(), c, d, a, b, X[10], 17, 0xffff5bb1); // 11 + operation(F(), b, c, d, a, X[11], 22, 0x895cd7be); // 12 + operation(F(), a, b, c, d, X[12], 7, 0x6b901122); // 13 + operation(F(), d, a, b, c, X[13], 12, 0xfd987193); // 14 + operation(F(), c, d, a, b, X[14], 17, 0xa679438e); // 15 + operation(F(), b, c, d, a, X[15], 22, 0x49b40821); // 16 + + // Round 2 + operation(G(), a, b, c, d, X[ 1], 5, 0xf61e2562); // 17 + operation(G(), d, a, b, c, X[ 6], 9, 0xc040b340); // 18 + operation(G(), c, d, a, b, X[11], 14, 0x265e5a51); // 19 + operation(G(), b, c, d, a, X[ 0], 20, 0xe9b6c7aa); // 20 + operation(G(), a, b, c, d, X[ 5], 5, 0xd62f105d); // 21 + operation(G(), d, a, b, c, X[10], 9, 0x2441453); // 22 + operation(G(), c, d, a, b, X[15], 14, 0xd8a1e681); // 23 + operation(G(), b, c, d, a, X[ 4], 20, 0xe7d3fbc8); // 24 + operation(G(), a, b, c, d, X[ 9], 5, 0x21e1cde6); // 25 + operation(G(), d, a, b, c, X[14], 9, 0xc33707d6); // 26 + operation(G(), c, d, a, b, X[ 3], 14, 0xf4d50d87); // 27 + operation(G(), b, c, d, a, X[ 8], 20, 0x455a14ed); // 28 + operation(G(), a, b, c, d, X[13], 5, 0xa9e3e905); // 29 + operation(G(), d, a, b, c, X[ 2], 9, 0xfcefa3f8); // 30 + operation(G(), c, d, a, b, X[ 7], 14, 0x676f02d9); // 31 + operation(G(), b, c, d, a, X[12], 20, 0x8d2a4c8a); // 32 + + // Round 3 + operation(H(), a, b, c, d, X[ 5], 4, 0xfffa3942); // 33 + operation(H(), d, a, b, c, X[ 8], 11, 0x8771f681); // 34 + operation(H(), c, d, a, b, X[11], 16, 0x6d9d6122); // 35 + operation(H(), b, c, d, a, X[14], 23, 0xfde5380c); // 36 + operation(H(), a, b, c, d, X[ 1], 4, 0xa4beea44); // 37 + operation(H(), d, a, b, c, X[ 4], 11, 0x4bdecfa9); // 38 + operation(H(), c, d, a, b, X[ 7], 16, 0xf6bb4b60); // 39 + operation(H(), b, c, d, a, X[10], 23, 0xbebfbc70); // 40 + operation(H(), a, b, c, d, X[13], 4, 0x289b7ec6); // 41 + operation(H(), d, a, b, c, X[ 0], 11, 0xeaa127fa); // 42 + operation(H(), c, d, a, b, X[ 3], 16, 0xd4ef3085); // 43 + operation(H(), b, c, d, a, X[ 6], 23, 0x4881d05); // 44 + operation(H(), a, b, c, d, X[ 9], 4, 0xd9d4d039); // 45 + operation(H(), d, a, b, c, X[12], 11, 0xe6db99e5); // 46 + operation(H(), c, d, a, b, X[15], 16, 0x1fa27cf8); // 47 + operation(H(), b, c, d, a, X[ 2], 23, 0xc4ac5665); // 48 + + // Round 4 + operation(I(), a, b, c, d, X[ 0], 6, 0xf4292244); // 49 + operation(I(), d, a, b, c, X[ 7], 10, 0x432aff97); // 50 + operation(I(), c, d, a, b, X[14], 15, 0xab9423a7); // 51 + operation(I(), b, c, d, a, X[ 5], 21, 0xfc93a039); // 52 + operation(I(), a, b, c, d, X[12], 6, 0x655b59c3); // 53 + operation(I(), d, a, b, c, X[ 3], 10, 0x8f0ccc92); // 54 + operation(I(), c, d, a, b, X[10], 15, 0xffeff47d); // 55 + operation(I(), b, c, d, a, X[ 1], 21, 0x85845dd1); // 56 + operation(I(), a, b, c, d, X[ 8], 6, 0x6fa87e4f); // 57 + operation(I(), d, a, b, c, X[15], 10, 0xfe2ce6e0); // 58 + operation(I(), c, d, a, b, X[ 6], 15, 0xa3014314); // 59 + operation(I(), b, c, d, a, X[13], 21, 0x4e0811a1); // 60 + operation(I(), a, b, c, d, X[ 4], 6, 0xf7537e82); // 61 + operation(I(), d, a, b, c, X[11], 10, 0xbd3af235); // 62 + operation(I(), c, d, a, b, X[ 2], 15, 0x2ad7d2bb); // 63 + operation(I(), b, c, d, a, X[ 9], 21, 0xeb86d391); // 64 + + state[0] += a; + state[1] += b; + state[2] += c; + state[3] += d; + +#if defined(SK_MD5_CLEAR_DATA) + // Clear sensitive information. + if (X == &storage) { + memset(storage, 0, sizeof(storage)); + } +#endif +} + +static void encode(uint8_t output[16], const uint32_t input[4]) { + for (size_t i = 0, j = 0; i < 4; i++, j += 4) { + output[j ] = (uint8_t) (input[i] & 0xff); + output[j+1] = (uint8_t)((input[i] >> 8) & 0xff); + output[j+2] = (uint8_t)((input[i] >> 16) & 0xff); + output[j+3] = (uint8_t)((input[i] >> 24) & 0xff); + } +} + +static void encode(uint8_t output[8], const uint64_t input) { + output[0] = (uint8_t) (input & 0xff); + output[1] = (uint8_t)((input >> 8) & 0xff); + output[2] = (uint8_t)((input >> 16) & 0xff); + output[3] = (uint8_t)((input >> 24) & 0xff); + output[4] = (uint8_t)((input >> 32) & 0xff); + output[5] = (uint8_t)((input >> 40) & 0xff); + output[6] = (uint8_t)((input >> 48) & 0xff); + output[7] = (uint8_t)((input >> 56) & 0xff); +} + +static inline bool is_aligned(const void *pointer, size_t byte_count) { + return reinterpret_cast(pointer) % byte_count == 0; +} + +static const uint32_t* decode(uint32_t storage[16], const uint8_t input[64]) { +#if defined(SK_CPU_LENDIAN) && defined(SK_CPU_FAST_UNALIGNED_ACCESS) + return reinterpret_cast(input); +#else +#if defined(SK_CPU_LENDIAN) + if (is_aligned(input, 4)) { + return reinterpret_cast(input); + } +#endif + for (size_t i = 0, j = 0; j < 64; i++, j += 4) { + storage[i] = ((uint32_t)input[j ]) | + (((uint32_t)input[j+1]) << 8) | + (((uint32_t)input[j+2]) << 16) | + (((uint32_t)input[j+3]) << 24); + } + return storage; +#endif +}