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gnupg/cipher/md5.c
1997-11-18 14:06:00 +00:00

421 lines
13 KiB
C

/* md5.c - MD5 Message-Digest Algorithm
* Copyright (c) 1994 by Werner Koch (dd9jn)
*
* This is a hacked version from WkLib
*
* This file is part of WkLib.
*
* WkLib 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.
*
* WkLib 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., 675 Mass Ave, Cambridge, MA 02139, USA.
***********************************************************************
** Copyright (C) 1990, RSA Data Security, Inc. All rights reserved. **
** **
** License to copy and use this software is granted provided that **
** it is identified as the "RSA Data Security, Inc. MD5 Message- **
** Digest Algorithm" in all material mentioning or referencing this **
** software or this function. **
** **
** License is also granted to make and use derivative works **
** provided that such works are identified as "derived from the RSA **
** Data Security, Inc. MD5 Message-Digest Algorithm" in all **
** material mentioning or referencing the derived work. **
** **
** RSA Data Security, Inc. makes no representations concerning **
** either the merchantability of this software or the suitability **
** of this software for any particular purpose. It is provided "as **
** is" without express or implied warranty of any kind. **
** **
** These notices must be retained in any copies of any part of this **
** documentation and/or software. **
***********************************************************************
*
* History:
* 16.01.95 wk now uses generic base-64 support
* 24.01.95 wk changed back to original base-64 coding, because
* the generic base-64 support was changed to go conform
* with RFC1113 !
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include "util.h"
#include "md5.h"
#include "memory.h"
#if __WATCOMC__ && defined(M_I86)
/* 16-Bit Compiler breaks Code in Function Transform() */
/* (at least when compiling for windows) */
#ifndef __SW_OD
#error must be compiled without optimizations
#endif
#endif
static void Init( MD5HANDLE mdContext);
static void Transform(u32 *buf,u32 *in);
static byte PADDING[64] = {
0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
};
/* F, G, H and I are basic MD5 functions */
#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
#define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
#define H(x, y, z) ((x) ^ (y) ^ (z))
#define I(x, y, z) ((y) ^ ((x) | (~z)))
/* ROTATE_LEFT rotates x left n bits */
#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
/* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4 */
/* Rotation is separate from addition to prevent recomputation */
#define FF(a, b, c, d, x, s, ac) \
{(a) += F ((b), (c), (d)) + (x) + (u32)(ac); \
(a) = ROTATE_LEFT ((a), (s)); \
(a) += (b); \
}
#define GG(a, b, c, d, x, s, ac) \
{(a) += G ((b), (c), (d)) + (x) + (u32)(ac); \
(a) = ROTATE_LEFT ((a), (s)); \
(a) += (b); \
}
#define HH(a, b, c, d, x, s, ac) \
{(a) += H ((b), (c), (d)) + (x) + (u32)(ac); \
(a) = ROTATE_LEFT ((a), (s)); \
(a) += (b); \
}
#define II(a, b, c, d, x, s, ac) \
{(a) += I ((b), (c), (d)) + (x) + (u32)(ac); \
(a) = ROTATE_LEFT ((a), (s)); \
(a) += (b); \
}
/* The routine Init initializes the message-digest context
* mdContext. All fields are set to zero.
* mode should be zero is reserved for extensions.
*/
MD5HANDLE
md5_open(int secure)
{
MD5HANDLE mdContext;
mdContext = secure? m_alloc_secure( sizeof *mdContext )
: m_alloc( sizeof *mdContext );
Init(mdContext);
return mdContext;
}
MD5HANDLE
md5_copy( MD5HANDLE a )
{
MD5HANDLE mdContext;
assert(a);
mdContext = m_is_secure(a)? m_alloc_secure( sizeof *mdContext )
: m_alloc( sizeof *mdContext );
memcpy( mdContext, a, sizeof *a );
return mdContext;
}
void
md5_close(MD5HANDLE hd)
{
if( hd )
m_free(hd);
}
static void
Init( MD5HANDLE mdContext)
{
mdContext->i[0] = mdContext->i[1] = (u32)0;
/* Load magic initialization constants.
*/
mdContext->buf[0] = (u32)0x67452301L;
mdContext->buf[1] = (u32)0xefcdab89L;
mdContext->buf[2] = (u32)0x98badcfeL;
mdContext->buf[3] = (u32)0x10325476L;
mdContext->bufcount = 0;
}
/* The routine Update updates the message-digest context to
* account for the presence of each of the characters inBuf[0..inLen-1]
* in the message whose digest is being computed.
*/
void
md5_write( MD5HANDLE mdContext, byte *inBuf, size_t inLen)
{
register int i, ii;
int mdi;
u32 in[16];
if(mdContext->bufcount) { /* flush the buffer */
i = mdContext->bufcount;
mdContext->bufcount = 0;
md5_write( mdContext, mdContext->digest, i);
}
if( !inBuf )
return;
/* compute number of bytes mod 64 */
mdi = (int)((mdContext->i[0] >> 3) & 0x3F);
/* update number of bits */
if((mdContext->i[0] + ((u32)inLen << 3)) < mdContext->i[0])
mdContext->i[1]++;
mdContext->i[0] += ((u32)inLen << 3);
mdContext->i[1] += ((u32)inLen >> 29);
while(inLen--) {
/* add new character to buffer, increment mdi */
mdContext->in[mdi++] = *inBuf++;
/* transform if necessary */
if( mdi == 0x40 ) {
for(i = 0, ii = 0; i < 16; i++, ii += 4)
in[i] = (((u32)mdContext->in[ii+3]) << 24) |
(((u32)mdContext->in[ii+2]) << 16) |
(((u32)mdContext->in[ii+1]) << 8) |
((u32)mdContext->in[ii]);
Transform(mdContext->buf, in);
mdi = 0;
}
}
}
/****************
* Process a single character, this character will be buffered to
* increase performance. The digest-field is used as a buffer.
*/
void
md5_putchar( MD5HANDLE mdContext, int c )
{
if(mdContext->bufcount == 16)
md5_write( mdContext, NULL, 0 );
mdContext->digest[mdContext->bufcount++] = c & 0xff;
}
/* The routine final terminates the message-digest computation and
* ends with the desired message digest in mdContext->digest[0...15].
* The handle is prepared for a new MD5 cycle.
* Returns 16 bytes representing the digest.
*/
void
md5_final(MD5HANDLE mdContext)
{
u32 in[16];
int mdi;
unsigned int i, ii;
unsigned int padLen;
if(mdContext->bufcount) /* flush buffer */
md5_write(mdContext, NULL, 0 );
/* save number of bits */
in[14] = mdContext->i[0];
in[15] = mdContext->i[1];
/* compute number of bytes mod 64 */
mdi = (int)((mdContext->i[0] >> 3) & 0x3F);
/* pad out to 56 mod 64 */
padLen = (mdi < 56) ? (56 - mdi) : (120 - mdi);
md5_write(mdContext, PADDING, padLen);
/* append length in bits and transform */
for(i = 0, ii = 0; i < 14; i++, ii += 4)
in[i] = (((u32)mdContext->in[ii+3]) << 24) |
(((u32)mdContext->in[ii+2]) << 16) |
(((u32)mdContext->in[ii+1]) << 8) |
((u32)mdContext->in[ii]);
Transform(mdContext->buf, in);
/* store buffer in digest */
for(i = 0, ii = 0; i < 4; i++, ii += 4) {
mdContext->digest[ii] = (byte)(mdContext->buf[i] & 0xFF);
mdContext->digest[ii+1] = (byte)((mdContext->buf[i] >> 8) & 0xFF);
mdContext->digest[ii+2] = (byte)((mdContext->buf[i] >> 16) & 0xFF);
mdContext->digest[ii+3] = (byte)((mdContext->buf[i] >> 24) & 0xFF);
}
Init(mdContext);
}
/**********
* Returns 16 bytes representing the digest.
*/
byte *
md5_read(MD5HANDLE mdContext)
{
return mdContext->digest;
}
/****************
* Converts the result form Read into a printable representation.
* This should only be used direct after a md5_read(), because it uses
* In-Place conversion.
* Returns digest.
*/
char *
md5_tostring( byte *digest )
{
static byte bintoasc[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ."
"abcdefghijklmnopqrstuvwxyz_"
"0123456789";
int i;
byte *d, *s;
memmove(digest+8,digest, 16); /* make some room */
d = digest;
s = digest+8;
for(i=0; i < 5; i++, s += 3 ) {
*d++ = bintoasc[(*s >> 2) & 077];
*d++ = bintoasc[(((*s << 4) & 060) | ((s[1] >> 4) & 017)) & 077];
*d++ = bintoasc[(((s[1] << 2) & 074) | ((s[2] >> 6) & 03)) & 077];
*d++ = bintoasc[s[2] & 077];
}
*d++ = bintoasc[(*s >> 2) & 077];
*d++ = bintoasc[((*s << 4) & 060) & 077];
*d = 0;
return (char*)digest;
}
/* Basic MD5 step. Transforms buf based on in. Note that if the Mysterious
* Constants are arranged backwards in little-endian order and decrypted with
* the DES they produce OCCULT MESSAGES!
*/
static void
Transform(register u32 *buf,register u32 *in)
{
register u32 a = buf[0], b = buf[1], c = buf[2], d = buf[3];
/* Round 1 */
#define S11 7
#define S12 12
#define S13 17
#define S14 22
FF ( a, b, c, d, in[ 0], S11, 0xD76AA478L); /* 1 */
FF ( d, a, b, c, in[ 1], S12, 0xE8C7B756L); /* 2 */
FF ( c, d, a, b, in[ 2], S13, 0x242070DBL); /* 3 */
FF ( b, c, d, a, in[ 3], S14, 0xC1BDCEEEL); /* 4 */
FF ( a, b, c, d, in[ 4], S11, 0xF57C0FAFL); /* 5 */
FF ( d, a, b, c, in[ 5], S12, 0x4787C62AL); /* 6 */
FF ( c, d, a, b, in[ 6], S13, 0xA8304613L); /* 7 */
FF ( b, c, d, a, in[ 7], S14, 0xFD469501L); /* 8 */
FF ( a, b, c, d, in[ 8], S11, 0x698098D8L); /* 9 */
FF ( d, a, b, c, in[ 9], S12, 0x8B44F7AFL); /* 10 */
FF ( c, d, a, b, in[10], S13, 0xFFFF5BB1L); /* 11 */
FF ( b, c, d, a, in[11], S14, 0x895CD7BEL); /* 12 */
FF ( a, b, c, d, in[12], S11, 0x6B901122L); /* 13 */
FF ( d, a, b, c, in[13], S12, 0xFD987193L); /* 14 */
FF ( c, d, a, b, in[14], S13, 0xA679438EL); /* 15 */
FF ( b, c, d, a, in[15], S14, 0x49B40821L); /* 16 */
/* Round 2 */
#define S21 5
#define S22 9
#define S23 14
#define S24 20
GG ( a, b, c, d, in[ 1], S21, 0xF61E2562L); /* 17 */
GG ( d, a, b, c, in[ 6], S22, 0xC040B340L); /* 18 */
GG ( c, d, a, b, in[11], S23, 0x265E5A51L); /* 19 */
GG ( b, c, d, a, in[ 0], S24, 0xE9B6C7AAL); /* 20 */
GG ( a, b, c, d, in[ 5], S21, 0xD62F105DL); /* 21 */
GG ( d, a, b, c, in[10], S22, 0x02441453L); /* 22 */
GG ( c, d, a, b, in[15], S23, 0xD8A1E681L); /* 23 */
GG ( b, c, d, a, in[ 4], S24, 0xE7D3FBC8L); /* 24 */
GG ( a, b, c, d, in[ 9], S21, 0x21E1CDE6L); /* 25 */
GG ( d, a, b, c, in[14], S22, 0xC33707D6L); /* 26 */
GG ( c, d, a, b, in[ 3], S23, 0xF4D50D87L); /* 27 */
GG ( b, c, d, a, in[ 8], S24, 0x455A14EDL); /* 28 */
GG ( a, b, c, d, in[13], S21, 0xA9E3E905L); /* 29 */
GG ( d, a, b, c, in[ 2], S22, 0xFCEFA3F8L); /* 30 */
GG ( c, d, a, b, in[ 7], S23, 0x676F02D9L); /* 31 */
GG ( b, c, d, a, in[12], S24, 0x8D2A4C8AL); /* 32 */
/* Round 3 */
#define S31 4
#define S32 11
#define S33 16
#define S34 23
HH ( a, b, c, d, in[ 5], S31, 0xFFFA3942L); /* 33 */
HH ( d, a, b, c, in[ 8], S32, 0x8771F681L); /* 34 */
HH ( c, d, a, b, in[11], S33, 0x6D9D6122L); /* 35 */
HH ( b, c, d, a, in[14], S34, 0xFDE5380CL); /* 36 */
HH ( a, b, c, d, in[ 1], S31, 0xA4BEEA44L); /* 37 */
HH ( d, a, b, c, in[ 4], S32, 0x4BDECFA9L); /* 38 */
HH ( c, d, a, b, in[ 7], S33, 0xF6BB4B60L); /* 39 */
HH ( b, c, d, a, in[10], S34, 0xBEBFBC70L); /* 40 */
HH ( a, b, c, d, in[13], S31, 0x289B7EC6L); /* 41 */
HH ( d, a, b, c, in[ 0], S32, 0xEAA127FAL); /* 42 */
HH ( c, d, a, b, in[ 3], S33, 0xD4EF3085L); /* 43 */
HH ( b, c, d, a, in[ 6], S34, 0x04881D05L); /* 44 */
HH ( a, b, c, d, in[ 9], S31, 0xD9D4D039L); /* 45 */
HH ( d, a, b, c, in[12], S32, 0xE6DB99E5L); /* 46 */
HH ( c, d, a, b, in[15], S33, 0x1FA27CF8L); /* 47 */
HH ( b, c, d, a, in[ 2], S34, 0xC4AC5665L); /* 48 */
/* Round 4 */
#define S41 6
#define S42 10
#define S43 15
#define S44 21
II ( a, b, c, d, in[ 0], S41, 0xF4292244L); /* 49 */
II ( d, a, b, c, in[ 7], S42, 0x432AFF97L); /* 50 */
II ( c, d, a, b, in[14], S43, 0xAB9423A7L); /* 51 */
II ( b, c, d, a, in[ 5], S44, 0xFC93A039L); /* 52 */
II ( a, b, c, d, in[12], S41, 0x655B59C3L); /* 53 */
II ( d, a, b, c, in[ 3], S42, 0x8F0CCC92L); /* 54 */
II ( c, d, a, b, in[10], S43, 0xFFEFF47DL); /* 55 */
II ( b, c, d, a, in[ 1], S44, 0x85845DD1L); /* 56 */
II ( a, b, c, d, in[ 8], S41, 0x6FA87E4FL); /* 57 */
II ( d, a, b, c, in[15], S42, 0xFE2CE6E0L); /* 58 */
II ( c, d, a, b, in[ 6], S43, 0xA3014314L); /* 59 */
II ( b, c, d, a, in[13], S44, 0x4E0811A1L); /* 60 */
II ( a, b, c, d, in[ 4], S41, 0xF7537E82L); /* 61 */
II ( d, a, b, c, in[11], S42, 0xBD3AF235L); /* 62 */
II ( c, d, a, b, in[ 2], S43, 0x2AD7D2BBL); /* 63 */
II ( b, c, d, a, in[ 9], S44, 0xEB86D391L); /* 64 */
buf[0] += a;
buf[1] += b;
buf[2] += c;
buf[3] += d;
}
/* end of file */