| 0,0 → 1,182 |
|---|
| /* |
| This code is based on the code found from 7-Zip, which has a modified |
| version of the SHA-256 found from Crypto++ <http://www.cryptopp.com/>. |
| The code was modified a little to fit into liblzma and fitz. |
| |
| This file has been put into the public domain. |
| You can do whatever you want with this file. |
| */ |
| |
| #include "fitz.h" |
| |
| static inline int isbigendian(void) |
| { |
| static const int one = 1; |
| return *(char*)&one == 0; |
| } |
| |
| static inline unsigned int bswap32(unsigned int num) |
| { |
| if (!isbigendian()) |
| { |
| return ( (((num) << 24)) |
| | (((num) << 8) & 0x00FF0000) |
| | (((num) >> 8) & 0x0000FF00) |
| | (((num) >> 24)) ); |
| } |
| return num; |
| } |
| |
| /* At least on x86, GCC is able to optimize this to a rotate instruction. */ |
| #define rotr_32(num, amount) ((num) >> (amount) | (num) << (32 - (amount))) |
| |
| #define blk0(i) (W[i] = data[i]) |
| #define blk2(i) (W[i & 15] += s1(W[(i - 2) & 15]) + W[(i - 7) & 15] \ |
| + s0(W[(i - 15) & 15])) |
| |
| #define Ch(x, y, z) (z ^ (x & (y ^ z))) |
| #define Maj(x, y, z) ((x & y) | (z & (x | y))) |
| |
| #define a(i) T[(0 - i) & 7] |
| #define b(i) T[(1 - i) & 7] |
| #define c(i) T[(2 - i) & 7] |
| #define d(i) T[(3 - i) & 7] |
| #define e(i) T[(4 - i) & 7] |
| #define f(i) T[(5 - i) & 7] |
| #define g(i) T[(6 - i) & 7] |
| #define h(i) T[(7 - i) & 7] |
| |
| #define R(i) \ |
| h(i) += S1(e(i)) + Ch(e(i), f(i), g(i)) + SHA256_K[i + j] \ |
| + (j ? blk2(i) : blk0(i)); \ |
| d(i) += h(i); \ |
| h(i) += S0(a(i)) + Maj(a(i), b(i), c(i)) |
| |
| #define S0(x) (rotr_32(x, 2) ^ rotr_32(x, 13) ^ rotr_32(x, 22)) |
| #define S1(x) (rotr_32(x, 6) ^ rotr_32(x, 11) ^ rotr_32(x, 25)) |
| #define s0(x) (rotr_32(x, 7) ^ rotr_32(x, 18) ^ (x >> 3)) |
| #define s1(x) (rotr_32(x, 17) ^ rotr_32(x, 19) ^ (x >> 10)) |
| |
| static const unsigned int SHA256_K[64] = { |
| 0x428A2F98, 0x71374491, 0xB5C0FBCF, 0xE9B5DBA5, |
| 0x3956C25B, 0x59F111F1, 0x923F82A4, 0xAB1C5ED5, |
| 0xD807AA98, 0x12835B01, 0x243185BE, 0x550C7DC3, |
| 0x72BE5D74, 0x80DEB1FE, 0x9BDC06A7, 0xC19BF174, |
| 0xE49B69C1, 0xEFBE4786, 0x0FC19DC6, 0x240CA1CC, |
| 0x2DE92C6F, 0x4A7484AA, 0x5CB0A9DC, 0x76F988DA, |
| 0x983E5152, 0xA831C66D, 0xB00327C8, 0xBF597FC7, |
| 0xC6E00BF3, 0xD5A79147, 0x06CA6351, 0x14292967, |
| 0x27B70A85, 0x2E1B2138, 0x4D2C6DFC, 0x53380D13, |
| 0x650A7354, 0x766A0ABB, 0x81C2C92E, 0x92722C85, |
| 0xA2BFE8A1, 0xA81A664B, 0xC24B8B70, 0xC76C51A3, |
| 0xD192E819, 0xD6990624, 0xF40E3585, 0x106AA070, |
| 0x19A4C116, 0x1E376C08, 0x2748774C, 0x34B0BCB5, |
| 0x391C0CB3, 0x4ED8AA4A, 0x5B9CCA4F, 0x682E6FF3, |
| 0x748F82EE, 0x78A5636F, 0x84C87814, 0x8CC70208, |
| 0x90BEFFFA, 0xA4506CEB, 0xBEF9A3F7, 0xC67178F2, |
| }; |
| |
| static void |
| transform(unsigned int state[8], const unsigned int data_xe[16]) |
| { |
| unsigned int data[16]; |
| unsigned int W[16]; |
| unsigned int T[8]; |
| unsigned int j; |
| |
| /* ensure big-endian integers */ |
| for (j = 0; j < 16; j++) |
| data[j] = bswap32(data_xe[j]); |
| |
| /* Copy state[] to working vars. */ |
| memcpy(T, state, sizeof(T)); |
| |
| /* 64 operations, partially loop unrolled */ |
| for (j = 0; j < 64; j += 16) { |
| R( 0); R( 1); R( 2); R( 3); |
| R( 4); R( 5); R( 6); R( 7); |
| R( 8); R( 9); R(10); R(11); |
| R(12); R(13); R(14); R(15); |
| } |
| |
| /* Add the working vars back into state[]. */ |
| state[0] += a(0); |
| state[1] += b(0); |
| state[2] += c(0); |
| state[3] += d(0); |
| state[4] += e(0); |
| state[5] += f(0); |
| state[6] += g(0); |
| state[7] += h(0); |
| } |
| |
| void fz_sha256_init(fz_sha256 *context) |
| { |
| context->count[0] = context->count[1] = 0; |
| |
| context->state[0] = 0x6A09E667; |
| context->state[1] = 0xBB67AE85; |
| context->state[2] = 0x3C6EF372; |
| context->state[3] = 0xA54FF53A; |
| context->state[4] = 0x510E527F; |
| context->state[5] = 0x9B05688C; |
| context->state[6] = 0x1F83D9AB; |
| context->state[7] = 0x5BE0CD19; |
| } |
| |
| void fz_sha256_update(fz_sha256 *context, const unsigned char *input, unsigned int inlen) |
| { |
| /* Copy the input data into a properly aligned temporary buffer. |
| * This way we can be called with arbitrarily sized buffers |
| * (no need to be multiple of 64 bytes), and the code works also |
| * on architectures that don't allow unaligned memory access. */ |
| while (inlen > 0) |
| { |
| const unsigned int copy_start = context->count[0] & 0x3F; |
| unsigned int copy_size = 64 - copy_start; |
| if (copy_size > inlen) |
| copy_size = inlen; |
| |
| memcpy(context->buffer.u8 + copy_start, input, copy_size); |
| |
| input += copy_size; |
| inlen -= copy_size; |
| context->count[0] += copy_size; |
| /* carry overflow from low to high */ |
| if (context->count[0] < copy_size) |
| context->count[1]++; |
| |
| if ((context->count[0] & 0x3F) == 0) |
| transform(context->state, context->buffer.u32); |
| } |
| } |
| |
| void fz_sha256_final(fz_sha256 *context, unsigned char digest[32]) |
| { |
| /* Add padding as described in RFC 3174 (it describes SHA-1 but |
| * the same padding style is used for SHA-256 too). */ |
| unsigned int j = context->count[0] & 0x3F; |
| context->buffer.u8[j++] = 0x80; |
| |
| while (j != 56) |
| { |
| if (j == 64) |
| { |
| transform(context->state, context->buffer.u32); |
| j = 0; |
| } |
| context->buffer.u8[j++] = 0x00; |
| } |
| |
| /* Convert the message size from bytes to bits. */ |
| context->count[1] = (context->count[1] << 3) + (context->count[0] >> 29); |
| context->count[0] = context->count[0] << 3; |
| |
| context->buffer.u32[14] = bswap32(context->count[1]); |
| context->buffer.u32[15] = bswap32(context->count[0]); |
| transform(context->state, context->buffer.u32); |
| |
| for (j = 0; j < 8; j++) |
| ((unsigned int *)digest)[j] = bswap32(context->state[j]); |
| memset(context, 0, sizeof(fz_sha256)); |
| } |