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sattools/qfits/src/md5.c

282 lines
8.7 KiB
C

/*----------------------------------------------------------------------------*/
/**
@file md5.c
@author N. Devillard
@date July 2001
@version $Revision: 1.3 $
@brief MD5 message-digest algorithm
The algorithm is due to Ron Rivest. This code was written by Colin Plumb
in 1993, no copyright is claimed. This code is in the public domain; do
with it what you wish.
Equivalent code is available from RSA Data Security, Inc. This code has
been tested against that, and is equivalent, except that you don't need to
include two pages of legalese with every copy.
To compute the message digest of a chunk of bytes, declare an MD5Context
structure, pass it to MD5Init, call MD5Update as needed on buffers full of
bytes, and then call MD5Final, which will fill a supplied 16-byte array with
the digest.
*/
/*----------------------------------------------------------------------------*/
/*
$Id: md5.c,v 1.3 2003/01/23 09:35:57 yjung Exp $
$Author: yjung $
$Date: 2003/01/23 09:35:57 $
$Revision: 1.3 $
*/
/*-----------------------------------------------------------------------------
Includes
-----------------------------------------------------------------------------*/
#include "md5.h"
#include <string.h>
/*-----------------------------------------------------------------------------
Function prototypes
-----------------------------------------------------------------------------*/
static void byteReverse (unsigned char *buf, unsigned longs);
/*-----------------------------------------------------------------------------
Function codes
-----------------------------------------------------------------------------*/
/*
* Note: this code is harmless on little-endian machines.
*/
static void
byteReverse (unsigned char *buf, unsigned longs)
{
word32 t;
do
{
t = (word32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
((unsigned) buf[1] << 8 | buf[0]);
*(word32 *) buf = t;
buf += 4;
}
while (--longs);
}
/*
* Start MD5 accumulation. Set bit count to 0 and buffer to mysterious
* initialization constants.
*/
void
MD5Init (struct MD5Context *ctx)
{
ctx->buf[0] = 0x67452301;
ctx->buf[1] = 0xefcdab89;
ctx->buf[2] = 0x98badcfe;
ctx->buf[3] = 0x10325476;
ctx->bits[0] = 0;
ctx->bits[1] = 0;
}
/*
* Update context to reflect the concatenation of another buffer full
* of bytes.
*/
void
MD5Update (struct MD5Context *ctx, unsigned char const *buf, unsigned len)
{
register word32 t;
/* Update bitcount */
t = ctx->bits[0];
if ((ctx->bits[0] = t + ((word32) len << 3)) < t)
ctx->bits[1]++; /* Carry from low to high */
ctx->bits[1] += len >> 29;
t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */
/* Handle any leading odd-sized chunks */
if (t)
{
unsigned char *p = (unsigned char *) ctx->in + t;
t = 64 - t;
if (len < t)
{
memmove (p, buf, len);
return;
}
memmove (p, buf, t);
byteReverse (ctx->in, 16);
MD5Transform (ctx->buf, (word32 *) ctx->in);
buf += t;
len -= t;
}
/* Process data in 64-byte chunks */
while (len >= 64)
{
memmove (ctx->in, buf, 64);
byteReverse (ctx->in, 16);
MD5Transform (ctx->buf, (word32 *) ctx->in);
buf += 64;
len -= 64;
}
/* Handle any remaining bytes of data. */
memmove (ctx->in, buf, len);
}
/*
* Final wrapup - pad to 64-byte boundary with the bit pattern
* 1 0* (64-bit count of bits processed, MSB-first)
*/
void
MD5Final (unsigned char digest[16], struct MD5Context *ctx)
{
unsigned int count;
unsigned char *p;
/* Compute number of bytes mod 64 */
count = (ctx->bits[0] >> 3) & 0x3F;
/* Set the first char of padding to 0x80. This is safe since there is
always at least one byte free */
p = ctx->in + count;
*p++ = 0x80;
/* Bytes of padding needed to make 64 bytes */
count = 64 - 1 - count;
/* Pad out to 56 mod 64 */
if (count < 8)
{
/* Two lots of padding: Pad the first block to 64 bytes */
memset (p, 0, count);
byteReverse (ctx->in, 16);
MD5Transform (ctx->buf, (word32 *) ctx->in);
/* Now fill the next block with 56 bytes */
memset (ctx->in, 0, 56);
}
else
{
/* Pad block to 56 bytes */
memset (p, 0, count - 8);
}
byteReverse (ctx->in, 14);
/* Append length in bits and transform */
((word32 *) ctx->in)[14] = ctx->bits[0];
((word32 *) ctx->in)[15] = ctx->bits[1];
MD5Transform (ctx->buf, (word32 *) ctx->in);
byteReverse ((unsigned char *) ctx->buf, 4);
memmove (digest, ctx->buf, 16);
memset (ctx, 0, sizeof (ctx)); /* In case it's sensitive */
}
/* The four core functions - F1 is optimized somewhat */
/* #define F1(x, y, z) (x & y | ~x & z) */
#define F1(x, y, z) (z ^ (x & (y ^ z)))
#define F2(x, y, z) F1(z, x, y)
#define F3(x, y, z) (x ^ y ^ z)
#define F4(x, y, z) (y ^ (x | ~z))
/* This is the central step in the MD5 algorithm. */
#define MD5STEP(f, w, x, y, z, data, s) \
( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x )
/*
* The core of the MD5 algorithm, this alters an existing MD5 hash to
* reflect the addition of 16 longwords of new data. MD5Update blocks
* the data and converts bytes into longwords for this routine.
*/
void
MD5Transform (word32 buf[4], word32 const in[16])
{
register word32 a, b, c, d;
a = buf[0];
b = buf[1];
c = buf[2];
d = buf[3];
MD5STEP (F1, a, b, c, d, in[0] + 0xd76aa478, 7);
MD5STEP (F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
MD5STEP (F1, c, d, a, b, in[2] + 0x242070db, 17);
MD5STEP (F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
MD5STEP (F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
MD5STEP (F1, d, a, b, c, in[5] + 0x4787c62a, 12);
MD5STEP (F1, c, d, a, b, in[6] + 0xa8304613, 17);
MD5STEP (F1, b, c, d, a, in[7] + 0xfd469501, 22);
MD5STEP (F1, a, b, c, d, in[8] + 0x698098d8, 7);
MD5STEP (F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
MD5STEP (F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
MD5STEP (F1, b, c, d, a, in[11] + 0x895cd7be, 22);
MD5STEP (F1, a, b, c, d, in[12] + 0x6b901122, 7);
MD5STEP (F1, d, a, b, c, in[13] + 0xfd987193, 12);
MD5STEP (F1, c, d, a, b, in[14] + 0xa679438e, 17);
MD5STEP (F1, b, c, d, a, in[15] + 0x49b40821, 22);
MD5STEP (F2, a, b, c, d, in[1] + 0xf61e2562, 5);
MD5STEP (F2, d, a, b, c, in[6] + 0xc040b340, 9);
MD5STEP (F2, c, d, a, b, in[11] + 0x265e5a51, 14);
MD5STEP (F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
MD5STEP (F2, a, b, c, d, in[5] + 0xd62f105d, 5);
MD5STEP (F2, d, a, b, c, in[10] + 0x02441453, 9);
MD5STEP (F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
MD5STEP (F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
MD5STEP (F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
MD5STEP (F2, d, a, b, c, in[14] + 0xc33707d6, 9);
MD5STEP (F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
MD5STEP (F2, b, c, d, a, in[8] + 0x455a14ed, 20);
MD5STEP (F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
MD5STEP (F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
MD5STEP (F2, c, d, a, b, in[7] + 0x676f02d9, 14);
MD5STEP (F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
MD5STEP (F3, a, b, c, d, in[5] + 0xfffa3942, 4);
MD5STEP (F3, d, a, b, c, in[8] + 0x8771f681, 11);
MD5STEP (F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
MD5STEP (F3, b, c, d, a, in[14] + 0xfde5380c, 23);
MD5STEP (F3, a, b, c, d, in[1] + 0xa4beea44, 4);
MD5STEP (F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
MD5STEP (F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
MD5STEP (F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
MD5STEP (F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
MD5STEP (F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
MD5STEP (F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
MD5STEP (F3, b, c, d, a, in[6] + 0x04881d05, 23);
MD5STEP (F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
MD5STEP (F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
MD5STEP (F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
MD5STEP (F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
MD5STEP (F4, a, b, c, d, in[0] + 0xf4292244, 6);
MD5STEP (F4, d, a, b, c, in[7] + 0x432aff97, 10);
MD5STEP (F4, c, d, a, b, in[14] + 0xab9423a7, 15);
MD5STEP (F4, b, c, d, a, in[5] + 0xfc93a039, 21);
MD5STEP (F4, a, b, c, d, in[12] + 0x655b59c3, 6);
MD5STEP (F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
MD5STEP (F4, c, d, a, b, in[10] + 0xffeff47d, 15);
MD5STEP (F4, b, c, d, a, in[1] + 0x85845dd1, 21);
MD5STEP (F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
MD5STEP (F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
MD5STEP (F4, c, d, a, b, in[6] + 0xa3014314, 15);
MD5STEP (F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
MD5STEP (F4, a, b, c, d, in[4] + 0xf7537e82, 6);
MD5STEP (F4, d, a, b, c, in[11] + 0xbd3af235, 10);
MD5STEP (F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
MD5STEP (F4, b, c, d, a, in[9] + 0xeb86d391, 21);
buf[0] += a;
buf[1] += b;
buf[2] += c;
buf[3] += d;
}
/* vim: set ts=4 et sw=4 tw=75 */