diff options
author | Bastien Montagne <montagne29@wanadoo.fr> | 2014-11-14 13:00:10 +0300 |
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committer | Bastien Montagne <montagne29@wanadoo.fr> | 2014-11-14 13:00:26 +0300 |
commit | 64c0c13e6e08c51e92504631468db864f553d9b5 (patch) | |
tree | 5903262689a45defda7a98782656964bdaa50f6b /source/blender/blenlib/intern/md5.c | |
parent | c8a9764987a8c1e7ea0093e8a0b028a65af6ee33 (diff) |
Add Murmur2A hashing feature to BLI
Murmur2a is a very fast hashing function generation int32 hashes.
It also features a very good distribution of generated hashes.
However, it is not endianness-agnostic, meaning it will usually generate
different hashes for a same key on big- and little-endian architectures.
Consequently, **it shall not be used to generate persistent hashes**
(never store them in .blend file e.g.).
This implementation supports incremental hashing, and is a direct
adaptation of reference implementation (in c++):
https://smhasher.googlecode.com/svn-history/r130/trunk/MurmurHash2.cpp
That cpp code was also used to generate reference values in gtests file.
Reviewers: sergey, campbellbarton
Reviewed By: campbellbarton
Projects: #bf_blender
Differential Revision: https://developer.blender.org/D892
Diffstat (limited to 'source/blender/blenlib/intern/md5.c')
-rw-r--r-- | source/blender/blenlib/intern/md5.c | 408 |
1 files changed, 0 insertions, 408 deletions
diff --git a/source/blender/blenlib/intern/md5.c b/source/blender/blenlib/intern/md5.c deleted file mode 100644 index 3d1a9cdb7a4..00000000000 --- a/source/blender/blenlib/intern/md5.c +++ /dev/null @@ -1,408 +0,0 @@ -/* - * ***** BEGIN GPL LICENSE BLOCK ***** - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version 2 - * of the License, or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software Foundation, - * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. - * - * ***** END GPL LICENSE BLOCK ***** - * - * Copyright (C) 1995 Software Foundation, Inc. - * - * Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>. - */ - -/** \file blender/blenlib/intern/md5.c - * \ingroup bli - * - * Functions to compute MD5 message digest of files or memory blocks - * according to the definition of MD5 in RFC 1321 from April 1992. - */ - -#include "BLI_md5.h" /* own include */ - -#include <stdlib.h> -#include <string.h> -#include <stdio.h> -#include <sys/types.h> - -#if defined HAVE_LIMITS_H || defined _LIBC -# include <limits.h> -#endif - -/* The following contortions are an attempt to use the C preprocessor to determine an unsigned integral type - * that is 32 bits wide. An alternative approach is to use autoconf's AC_CHECK_SIZEOF macro, but doing that - * would require that the configure script compile and *run* the resulting executable. - * Locally running cross-compiled executables is usually not possible. - */ - -#if defined __STDC__ && __STDC__ -# define UINT_MAX_32_BITS 4294967295U -#else -# define UINT_MAX_32_BITS 0xFFFFFFFF -#endif - -/* If UINT_MAX isn't defined, assume it's a 32-bit type. - * This should be valid for all systems GNU cares about because that doesn't include 16-bit systems, - * and only modern systems (that certainly have <limits.h>) have 64+-bit integral types. - */ - -#ifndef UINT_MAX -# define UINT_MAX UINT_MAX_32_BITS -#endif - -#if UINT_MAX == UINT_MAX_32_BITS - typedef unsigned int md5_uint32; -#else -# if USHRT_MAX == UINT_MAX_32_BITS - typedef unsigned short md5_uint32; -# else -# if ULONG_MAX == UINT_MAX_32_BITS - typedef unsigned long md5_uint32; -# else - /* The following line is intended to evoke an error. Using #error is not portable enough. */ - "Cannot determine unsigned 32-bit data type." -# endif -# endif -#endif - - -/* Following code is low level, upon which are built up the functions 'md5_stream' and 'md5_buffer'. */ - -/* Structure to save state of computation between the single steps. */ -struct md5_ctx -{ - md5_uint32 A; - md5_uint32 B; - md5_uint32 C; - md5_uint32 D; -}; - -#ifdef __BIG_ENDIAN__ -# define SWAP(n) (((n) << 24) | (((n) & 0xff00) << 8) | (((n) >> 8) & 0xff00) | ((n) >> 24)) -#else -# define SWAP(n) (n) -#endif - -/* This array contains the bytes used to pad the buffer to the next 64-byte boundary. (RFC 1321, 3.1: Step 1) */ -static const unsigned char fillbuf[64] = {0x80, 0 /* , 0, 0, ... */}; - -/** Initialize structure containing state of computation. - * (RFC 1321, 3.3: Step 3) - */ -static void md5_init_ctx(struct md5_ctx *ctx) -{ - ctx->A = 0x67452301; - ctx->B = 0xefcdab89; - ctx->C = 0x98badcfe; - ctx->D = 0x10325476; -} - -/** Starting with the result of former calls of this function (or the initialization), this function updates - * the 'ctx' context for the next 'len' bytes starting at 'buffer'. - * It is necessary that 'len' is a multiple of 64!!! - */ -static void md5_process_block (const void *buffer, size_t len, struct md5_ctx *ctx) -{ -/* These are the four functions used in the four steps of the MD5 algorithm and defined in the RFC 1321. - * The first function is a little bit optimized (as found in Colin Plumbs public domain implementation). - */ -/* #define FF(b, c, d) ((b & c) | (~b & d)) */ -#define FF(b, c, d) (d ^ (b & (c ^ d))) -#define FG(b, c, d) FF (d, b, c) -#define FH(b, c, d) (b ^ c ^ d) -#define FI(b, c, d) (c ^ (b | ~d)) - -/* It is unfortunate that C does not provide an operator for cyclic rotation. Hope the C compiler is smart enough. */ -#define CYCLIC(w, s) (w = (w << s) | (w >> (32 - s))) - - md5_uint32 correct_words[16]; - const md5_uint32 *words = buffer; - size_t nwords = len / sizeof(md5_uint32); - const md5_uint32 *endp = words + nwords; - md5_uint32 A = ctx->A; - md5_uint32 B = ctx->B; - md5_uint32 C = ctx->C; - md5_uint32 D = ctx->D; - - /* Process all bytes in the buffer with 64 bytes in each round of the loop. */ - while (words < endp) { - md5_uint32 *cwp = correct_words; - md5_uint32 A_save = A; - md5_uint32 B_save = B; - md5_uint32 C_save = C; - md5_uint32 D_save = D; - - /* First round: using the given function, the context and a constant the next context is computed. - * Because the algorithms processing unit is a 32-bit word and it is determined to work on words in - * little endian byte order we perhaps have to change the byte order before the computation. - * To reduce the work for the next steps we store the swapped words in the array CORRECT_WORDS. - */ -#define OP(a, b, c, d, s, T) \ - a += FF(b, c, d) + (*cwp++ = SWAP(*words)) + T; \ - ++words; \ - CYCLIC(a, s); \ - a += b; \ - (void)0 - - /* Before we start, one word to the strange constants. They are defined in RFC 1321 as: - * T[i] = (int) (4294967296.0 * fabs (sin (i))), i=1..64 - */ - - /* Round 1. */ - OP(A, B, C, D, 7, 0xd76aa478); - OP(D, A, B, C, 12, 0xe8c7b756); - OP(C, D, A, B, 17, 0x242070db); - OP(B, C, D, A, 22, 0xc1bdceee); - OP(A, B, C, D, 7, 0xf57c0faf); - OP(D, A, B, C, 12, 0x4787c62a); - OP(C, D, A, B, 17, 0xa8304613); - OP(B, C, D, A, 22, 0xfd469501); - OP(A, B, C, D, 7, 0x698098d8); - OP(D, A, B, C, 12, 0x8b44f7af); - OP(C, D, A, B, 17, 0xffff5bb1); - OP(B, C, D, A, 22, 0x895cd7be); - OP(A, B, C, D, 7, 0x6b901122); - OP(D, A, B, C, 12, 0xfd987193); - OP(C, D, A, B, 17, 0xa679438e); - OP(B, C, D, A, 22, 0x49b40821); - -#undef OP - - /* For the second to fourth round we have the possibly swapped words in CORRECT_WORDS. - * Redefine the macro to take an additional first argument specifying the function to use. - */ -#define OP(f, a, b, c, d, k, s, T) \ - a += f(b, c, d) + correct_words[k] + T; \ - CYCLIC(a, s); \ - a += b; \ - (void)0 - - /* Round 2. */ - OP(FG, A, B, C, D, 1, 5, 0xf61e2562); - OP(FG, D, A, B, C, 6, 9, 0xc040b340); - OP(FG, C, D, A, B, 11, 14, 0x265e5a51); - OP(FG, B, C, D, A, 0, 20, 0xe9b6c7aa); - OP(FG, A, B, C, D, 5, 5, 0xd62f105d); - OP(FG, D, A, B, C, 10, 9, 0x02441453); - OP(FG, C, D, A, B, 15, 14, 0xd8a1e681); - OP(FG, B, C, D, A, 4, 20, 0xe7d3fbc8); - OP(FG, A, B, C, D, 9, 5, 0x21e1cde6); - OP(FG, D, A, B, C, 14, 9, 0xc33707d6); - OP(FG, C, D, A, B, 3, 14, 0xf4d50d87); - OP(FG, B, C, D, A, 8, 20, 0x455a14ed); - OP(FG, A, B, C, D, 13, 5, 0xa9e3e905); - OP(FG, D, A, B, C, 2, 9, 0xfcefa3f8); - OP(FG, C, D, A, B, 7, 14, 0x676f02d9); - OP(FG, B, C, D, A, 12, 20, 0x8d2a4c8a); - - /* Round 3. */ - OP(FH, A, B, C, D, 5, 4, 0xfffa3942); - OP(FH, D, A, B, C, 8, 11, 0x8771f681); - OP(FH, C, D, A, B, 11, 16, 0x6d9d6122); - OP(FH, B, C, D, A, 14, 23, 0xfde5380c); - OP(FH, A, B, C, D, 1, 4, 0xa4beea44); - OP(FH, D, A, B, C, 4, 11, 0x4bdecfa9); - OP(FH, C, D, A, B, 7, 16, 0xf6bb4b60); - OP(FH, B, C, D, A, 10, 23, 0xbebfbc70); - OP(FH, A, B, C, D, 13, 4, 0x289b7ec6); - OP(FH, D, A, B, C, 0, 11, 0xeaa127fa); - OP(FH, C, D, A, B, 3, 16, 0xd4ef3085); - OP(FH, B, C, D, A, 6, 23, 0x04881d05); - OP(FH, A, B, C, D, 9, 4, 0xd9d4d039); - OP(FH, D, A, B, C, 12, 11, 0xe6db99e5); - OP(FH, C, D, A, B, 15, 16, 0x1fa27cf8); - OP(FH, B, C, D, A, 2, 23, 0xc4ac5665); - - /* Round 4. */ - OP(FI, A, B, C, D, 0, 6, 0xf4292244); - OP(FI, D, A, B, C, 7, 10, 0x432aff97); - OP(FI, C, D, A, B, 14, 15, 0xab9423a7); - OP(FI, B, C, D, A, 5, 21, 0xfc93a039); - OP(FI, A, B, C, D, 12, 6, 0x655b59c3); - OP(FI, D, A, B, C, 3, 10, 0x8f0ccc92); - OP(FI, C, D, A, B, 10, 15, 0xffeff47d); - OP(FI, B, C, D, A, 1, 21, 0x85845dd1); - OP(FI, A, B, C, D, 8, 6, 0x6fa87e4f); - OP(FI, D, A, B, C, 15, 10, 0xfe2ce6e0); - OP(FI, C, D, A, B, 6, 15, 0xa3014314); - OP(FI, B, C, D, A, 13, 21, 0x4e0811a1); - OP(FI, A, B, C, D, 4, 6, 0xf7537e82); - OP(FI, D, A, B, C, 11, 10, 0xbd3af235); - OP(FI, C, D, A, B, 2, 15, 0x2ad7d2bb); - OP(FI, B, C, D, A, 9, 21, 0xeb86d391); - -#undef OP - - /* Add the starting values of the context. */ - A += A_save; - B += B_save; - C += C_save; - D += D_save; - } - - /* Put checksum in context given as argument. */ - ctx->A = A; - ctx->B = B; - ctx->C = C; - ctx->D = D; - -#undef FF -#undef FG -#undef FH -#undef FI -#undef CYCLIC -} - -/** Put result from 'ctx' in first 16 bytes of 'resbuf'. The result is always in little endian byte order, - * so that a byte-wise output yields to the wanted ASCII representation of the message digest. - */ -static void *md5_read_ctx(const struct md5_ctx *ctx, void *resbuf) -{ - md5_uint32 *digest = resbuf; - digest[0] = SWAP(ctx->A); - digest[1] = SWAP(ctx->B); - digest[2] = SWAP(ctx->C); - digest[3] = SWAP(ctx->D); - - return resbuf; -} - -/* Top level public functions. */ - -/** Compute MD5 message digest for bytes read from 'stream'. - * The resulting message digest number will be written into the 16 bytes beginning at 'resblock'. - * \return Non-zero if an error occurred. - */ -int md5_stream(FILE *stream, void *resblock) -{ -#define BLOCKSIZE 4096 /* Important: must be a multiple of 64. */ - struct md5_ctx ctx; - md5_uint32 len[2]; - char buffer[BLOCKSIZE + 72]; - size_t pad, sum; - - /* Initialize the computation context. */ - md5_init_ctx(&ctx); - - len[0] = 0; - len[1] = 0; - - /* Iterate over full file contents. */ - while (1) { - /* We read the file in blocks of BLOCKSIZE bytes. One call of the computation function processes - * the whole buffer so that with the next round of the loop another block can be read. - */ - size_t n; - sum = 0; - - /* Read block. Take care for partial reads. */ - do { - n = fread(buffer, 1, BLOCKSIZE - sum, stream); - sum += n; - } while (sum < BLOCKSIZE && n != 0); - - if (n == 0 && ferror(stream)) - return 1; - - /* RFC 1321 specifies the possible length of the file up to 2^64 bits. - * Here we only compute the number of bytes. Do a double word increment. - */ - len[0] += sum; - if (len[0] < sum) - ++len[1]; - - /* If end of file is reached, end the loop. */ - if (n == 0) - break; - - /* Process buffer with BLOCKSIZE bytes. Note that BLOCKSIZE % 64 == 0. */ - md5_process_block(buffer, BLOCKSIZE, &ctx); - } - - /* We can copy 64 bytes because the buffer is always big enough. 'fillbuf' contains the needed bits. */ - memcpy(&buffer[sum], fillbuf, 64); - - /* Compute amount of padding bytes needed. Alignment is done to (N + PAD) % 64 == 56. - * There is always at least one byte padded, i.e. if the alignment is correctly aligned, - * 64 padding bytes are added. - */ - pad = sum & 63; - pad = pad >= 56 ? 64 + 56 - pad : 56 - pad; - - /* Put the 64-bit file length in *bits* at the end of the buffer. */ - *(md5_uint32 *) &buffer[sum + pad] = SWAP(len[0] << 3); - *(md5_uint32 *) &buffer[sum + pad + 4] = SWAP((len[1] << 3) | (len[0] >> 29)); - - /* Process last bytes. */ - md5_process_block(buffer, sum + pad + 8, &ctx); - - /* Construct result in desired memory. */ - md5_read_ctx(&ctx, resblock); - return 0; -} - -/** Compute MD5 message digest for 'len' bytes beginning at 'buffer'. - * The result is always in little endian byte order, so that a byte-wise output yields to the wanted - * ASCII representation of the message digest. - */ -void *md5_buffer(const char *buffer, size_t len, void *resblock) -{ - struct md5_ctx ctx; - char restbuf[64 + 72]; - size_t blocks = len & ~63; - size_t pad, rest; - - /* Initialize the computation context. */ - md5_init_ctx(&ctx); - - /* Process whole buffer but last len % 64 bytes. */ - md5_process_block(buffer, blocks, &ctx); - - /* REST bytes are not processed yet. */ - rest = len - blocks; - /* Copy to own buffer. */ - memcpy(restbuf, &buffer[blocks], rest); - /* Append needed fill bytes at end of buffer. We can copy 64 bytes because the buffer is always big enough. */ - memcpy(&restbuf[rest], fillbuf, 64); - - /* PAD bytes are used for padding to correct alignment. Note that always at least one byte is padded. */ - pad = rest >= 56 ? 64 + 56 - rest : 56 - rest; - - /* Put length of buffer in *bits* in last eight bytes. */ - *(md5_uint32 *) &restbuf[rest + pad] = (md5_uint32) SWAP(len << 3); - *(md5_uint32 *) &restbuf[rest + pad + 4] = (md5_uint32) SWAP(len >> 29); - - /* Process last bytes. */ - md5_process_block(restbuf, rest + pad + 8, &ctx); - - /* Put result in desired memory area. */ - return md5_read_ctx(&ctx, resblock); -} - -char *md5_to_hexdigest(void *resblock, char r_hex_digest[33]) -{ - static const char hex_map[17] = "0123456789abcdef"; - const unsigned char *p; - char *q; - short len; - - for (q = r_hex_digest, p = (const unsigned char *)resblock, len = 0; len < 16; ++p, ++len) { - const unsigned char c = *p; - *q++ = hex_map[c >> 4]; - *q++ = hex_map[c & 15]; - } - *q = '\0'; - - return r_hex_digest; -} |