From d6c74352427367a334d37469962bbcf1b9ae364c Mon Sep 17 00:00:00 2001 From: Timo Teras Date: Thu, 17 Apr 2008 14:09:13 +0000 Subject: Initial commit of some stuff written so far. Still in state of flux. Expect breakage and major changes. --- src/md5.c | 488 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 488 insertions(+) create mode 100644 src/md5.c (limited to 'src/md5.c') diff --git a/src/md5.c b/src/md5.c new file mode 100644 index 0000000..e165724 --- /dev/null +++ b/src/md5.c @@ -0,0 +1,488 @@ +/* md5.c - Compute MD5 checksum of files or strings according to the + * definition of MD5 in RFC 1321 from April 1992. + * Copyright (C) 1995-1999 Free Software Foundation, Inc. + * + * 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, 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +/* Written by Ulrich Drepper */ +/* Hacked to work with BusyBox by Alfred M. Szmidt */ + +/* Sucked directly into ipkg since the md5sum functions aren't in libbb + Dropped a few functions since ipkg only needs md5_stream. + Got rid of evil, twisted defines of FALSE=1 and TRUE=0 + 6 March 2002 Carl Worth +*/ + +/* + * June 29, 2001 Manuel Novoa III + * + * Added MD5SUM_SIZE_VS_SPEED configuration option. + * + * Current valid values, with data from my system for comparison, are: + * (using uClibc and running on linux-2.4.4.tar.bz2) + * user times (sec) text size (386) + * 0 (fastest) 1.1 6144 + * 1 1.4 5392 + * 2 3.0 5088 + * 3 (smallest) 5.1 4912 + */ + +#define MD5SUM_SIZE_VS_SPEED 0 + +/**********************************************************************/ + +#include +#include +#include +#include +#include +#include +#include +#include +#if defined HAVE_LIMITS_H +# include +#endif + +#include "md5.h" + +/* Handle endian-ness */ +#if __BYTE_ORDER == __LITTLE_ENDIAN +#define SWAP(n) (n) +#else +#define SWAP(n) ((n << 24) | ((n&65280)<<8) | ((n&16711680)>>8) | (n>>24)) +#endif + +#if MD5SUM_SIZE_VS_SPEED == 0 +/* 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, ... */ }; +#endif + +/* 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)) + +#define CYCLIC(w, s) (w = (w << s) | (w >> (32 - s))) + +/* Process LEN bytes of BUFFER, accumulating context into CTX. + It is assumed that LEN % 64 == 0. */ +static void md5_process_block(struct md5_ctx *ctx, + const void *buffer, size_t len) +{ + md5_uint32 correct_words[16]; + const md5_uint32 *words = buffer; + size_t nwords = len / sizeof(md5_uint32); + const md5_uint32 *endp = words + nwords; +#if MD5SUM_SIZE_VS_SPEED > 0 + static const md5_uint32 C_array[] = { + /* round 1 */ + 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee, + 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501, + 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be, + 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821, + /* round 2 */ + 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa, + 0xd62f105d, 0x2441453, 0xd8a1e681, 0xe7d3fbc8, + 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed, + 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a, + /* round 3 */ + 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c, + 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70, + 0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x4881d05, + 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665, + /* round 4 */ + 0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039, + 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1, + 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1, + 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391 + }; + + static const char P_array[] = { +#if MD5SUM_SIZE_VS_SPEED > 1 + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, /* 1 */ +#endif + 1, 6, 11, 0, 5, 10, 15, 4, 9, 14, 3, 8, 13, 2, 7, 12, /* 2 */ + 5, 8, 11, 14, 1, 4, 7, 10, 13, 0, 3, 6, 9, 12, 15, 2, /* 3 */ + 0, 7, 14, 5, 12, 3, 10, 1, 8, 15, 6, 13, 4, 11, 2, 9 /* 4 */ + }; + +#if MD5SUM_SIZE_VS_SPEED > 1 + static const char S_array[] = { + 7, 12, 17, 22, + 5, 9, 14, 20, + 4, 11, 16, 23, + 6, 10, 15, 21 + }; +#endif +#endif + + md5_uint32 A = ctx->A; + md5_uint32 B = ctx->B; + md5_uint32 C = ctx->C; + md5_uint32 D = ctx->D; + + /* First increment the byte count. 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. */ + ctx->total[0] += len; + if (ctx->total[0] < len) + ++ctx->total[1]; + + /* 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; + +#if MD5SUM_SIZE_VS_SPEED > 1 + const md5_uint32 *pc; + const char *pp; + const char *ps; + int i; + md5_uint32 temp; + + for ( i=0 ; i < 16 ; i++ ) { + cwp[i] = SWAP(words[i]); + } + words += 16; + +#if MD5SUM_SIZE_VS_SPEED > 2 + pc = C_array; pp = P_array; ps = S_array - 4; + + for ( i = 0 ; i < 64 ; i++ ) { + if ((i&0x0f) == 0) ps += 4; + temp = A; + switch (i>>4) { + case 0: + temp += FF(B,C,D); + break; + case 1: + temp += FG(B,C,D); + break; + case 2: + temp += FH(B,C,D); + break; + case 3: + temp += FI(B,C,D); + } + temp += cwp[(int)(*pp++)] + *pc++; + temp = CYCLIC(temp, ps[i&3]); + temp += B; + A = D; D = C; C = B; B = temp; + } +#else + pc = C_array; pp = P_array; ps = S_array; + + for ( i = 0 ; i < 16 ; i++ ) { + temp = A + FF(B,C,D) + cwp[(int)(*pp++)] + *pc++; + temp = CYCLIC (temp, ps[i&3]); + temp += B; + A = D; D = C; C = B; B = temp; + } + + ps += 4; + for ( i = 0 ; i < 16 ; i++ ) { + temp = A + FG(B,C,D) + cwp[(int)(*pp++)] + *pc++; + temp = CYCLIC (temp, ps[i&3]); + temp += B; + A = D; D = C; C = B; B = temp; + } + ps += 4; + for ( i = 0 ; i < 16 ; i++ ) { + temp = A + FH(B,C,D) + cwp[(int)(*pp++)] + *pc++; + temp = CYCLIC (temp, ps[i&3]); + temp += B; + A = D; D = C; C = B; B = temp; + } + ps += 4; + for ( i = 0 ; i < 16 ; i++ ) { + temp = A + FI(B,C,D) + cwp[(int)(*pp++)] + *pc++; + temp = CYCLIC (temp, ps[i&3]); + temp += B; + A = D; D = C; C = B; B = temp; + } + +#endif +#else + /* 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) \ + do \ + { \ + a += FF (b, c, d) + (*cwp++ = SWAP (*words)) + T; \ + ++words; \ + CYCLIC (a, s); \ + a += b; \ + } \ + while (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 + */ + +#if MD5SUM_SIZE_VS_SPEED == 1 + const md5_uint32 *pc; + const char *pp; + int i; +#endif + + /* Round 1. */ +#if MD5SUM_SIZE_VS_SPEED == 1 + pc = C_array; + for ( i=0 ; i < 4 ; i++ ) { + OP(A, B, C, D, 7, *pc++); + OP(D, A, B, C, 12, *pc++); + OP(C, D, A, B, 17, *pc++); + OP(B, C, D, A, 22, *pc++); + } +#else + 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); +#endif + + /* 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. */ +#undef OP +#define OP(f, a, b, c, d, k, s, T) \ + do \ + { \ + a += f (b, c, d) + correct_words[k] + T; \ + CYCLIC (a, s); \ + a += b; \ + } \ + while (0) + + /* Round 2. */ +#if MD5SUM_SIZE_VS_SPEED == 1 + pp = P_array; + for ( i=0 ; i < 4 ; i++ ) { + OP(FG, A, B, C, D, (int)(*pp++), 5, *pc++); + OP(FG, D, A, B, C, (int)(*pp++), 9, *pc++); + OP(FG, C, D, A, B, (int)(*pp++), 14, *pc++); + OP(FG, B, C, D, A, (int)(*pp++), 20, *pc++); + } +#else + 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); +#endif + + /* Round 3. */ +#if MD5SUM_SIZE_VS_SPEED == 1 + for ( i=0 ; i < 4 ; i++ ) { + OP(FH, A, B, C, D, (int)(*pp++), 4, *pc++); + OP(FH, D, A, B, C, (int)(*pp++), 11, *pc++); + OP(FH, C, D, A, B, (int)(*pp++), 16, *pc++); + OP(FH, B, C, D, A, (int)(*pp++), 23, *pc++); + } +#else + 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); +#endif + + /* Round 4. */ +#if MD5SUM_SIZE_VS_SPEED == 1 + for ( i=0 ; i < 4 ; i++ ) { + OP(FI, A, B, C, D, (int)(*pp++), 6, *pc++); + OP(FI, D, A, B, C, (int)(*pp++), 10, *pc++); + OP(FI, C, D, A, B, (int)(*pp++), 15, *pc++); + OP(FI, B, C, D, A, (int)(*pp++), 21, *pc++); + } +#else + 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); +#endif +#endif + + /* 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; +} + +/* Initialize structure containing state of computation. + (RFC 1321, 3.3: Step 3) */ +void md5_init(struct md5_ctx *ctx) +{ + ctx->A = 0x67452301; + ctx->B = 0xefcdab89; + ctx->C = 0x98badcfe; + ctx->D = 0x10325476; + + ctx->total[0] = ctx->total[1] = 0; + ctx->buflen = 0; +} + +void md5_process(struct md5_ctx *ctx, const void *buffer, size_t len) +{ + /* When we already have some bits in our internal buffer concatenate + both inputs first. */ + if (ctx->buflen != 0) { + size_t left_over = ctx->buflen; + size_t add = 128 - left_over > len ? len : 128 - left_over; + + memcpy(&ctx->buffer[left_over], buffer, add); + ctx->buflen += add; + + if (left_over + add > 64) { + md5_process_block(ctx, ctx->buffer, (left_over + add) & ~63); + /* The regions in the following copy operation cannot overlap. */ + memcpy(ctx->buffer, &ctx->buffer[(left_over + add) & ~63], + (left_over + add) & 63); + ctx->buflen = (left_over + add) & 63; + } + + buffer = (const char *) buffer + add; + len -= add; + } + + /* Process available complete blocks. */ + if (len > 64) { + md5_process_block(ctx, buffer, len & ~63); + buffer = (const char *) buffer + (len & ~63); + len &= 63; + } + + /* Move remaining bytes in internal buffer. */ + if (len > 0) { + memcpy(ctx->buffer, buffer, len); + ctx->buflen = len; + } +} + +/* Process the remaining bytes in the internal buffer and the usual + prolog according to the standard and write the result to RESBUF. + + IMPORTANT: On some systems it is required that RESBUF is correctly + aligned for a 32 bits value. */ +void md5_finish(struct md5_ctx *ctx, md5sum_t resbuf) +{ + /* Take yet unprocessed bytes into account. */ + md5_uint32 bytes = ctx->buflen; + size_t pad; + + /* Now count remaining bytes. */ + ctx->total[0] += bytes; + if (ctx->total[0] < bytes) + ++ctx->total[1]; + + pad = bytes >= 56 ? 64 + 56 - bytes : 56 - bytes; +#if MD5SUM_SIZE_VS_SPEED > 0 + memset(&ctx->buffer[bytes], 0, pad); + ctx->buffer[bytes] = 0x80; +#else + memcpy(&ctx->buffer[bytes], fillbuf, pad); +#endif + + /* Put the 64-bit file length in *bits* at the end of the buffer. */ + *(md5_uint32 *) & ctx->buffer[bytes + pad] = SWAP(ctx->total[0] << 3); + *(md5_uint32 *) & ctx->buffer[bytes + pad + 4] = + SWAP( ((ctx->total[1] << 3) | (ctx->total[0] >> 29)) ); + + /* Process last bytes. */ + md5_process_block(ctx, ctx->buffer, bytes + pad + 8); + + /* Put result from CTX in first 16 bytes following 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. + + IMPORTANT: On some systems it is required that RESBUF is correctly + aligned for a 32 bits value. */ + ((md5_uint32 *) resbuf)[0] = SWAP(ctx->A); + ((md5_uint32 *) resbuf)[1] = SWAP(ctx->B); + ((md5_uint32 *) resbuf)[2] = SWAP(ctx->C); + ((md5_uint32 *) resbuf)[3] = SWAP(ctx->D); +} + -- cgit v1.2.3-70-g09d2