md5sum.c, md5.c, md5.h

#include <stdio.h>

#include <stdlib.h>

#include "md5.h"



#pragma warning(disable:4996)



#define BUFFER_SIZE        0x200000



void print_digest(const unsigned char* digest);

void print_digest(const unsigned char* digest) {

    int    i;



    for ( i = 0; i < 16; i++ ) {

        printf("%02x", *digest++);

    }

}



int main(int argc, char* argv[]) {

    struct MD5Context    md5;

    unsigned char*        buffer;

    unsigned char        digest[16];

    size_t                len;

    FILE*                file;

    int                    i;



    // check the arguments.

    if ( argc < 2 ) {

        printf("use this program as:
 md5sum file1 file2 file3...
");

        return(1);

    }

    // Get the memory as the buffer.

    buffer = (unsigned char*)malloc(BUFFER_SIZE);

    if ( buffer == NULL ) {

        printf("Have not enought memory to do this work!
");

        return(2);

    }

    // One by one.

    for ( i = 1; i < argc; i++ ) {

        MD5Init(&md5);

        // open the file.

        file = fopen(argv[i], "rb");

        if ( file == NULL ) {

            printf("Can't open file: %s
", argv[i]);

            continue;

        }

        // read the data from the file.

        while ( (len = fread((void*)buffer, 1, BUFFER_SIZE, file)) > 0 ) {

            MD5Update(&md5, (const unsigned char*)buffer, (unsigned int)len);

        }

        // Finish and show it.

        MD5Final(digest, &md5);

        fclose(file);

        printf("%s: ", argv[i]);

        print_digest((const unsigned char*)digest);

        printf("
");

    }

    // Free the memory.

    free((void*)buffer);



    return(0);

}

/*

 * This code implements the 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.

 */

#include <string.h>        /* for memcpy() */

#include "md5.h"

#ifndef HIGHFIRST

#define byteReverse(buf, len)    /* Nothing */

#else

void byteReverse(unsigned char *buf, unsigned longs);



#ifndef ASM_MD5

/*

 * Note: this code is harmless on little-endian machines.

 */

void byteReverse(unsigned char *buf, unsigned longs)

{

    unsigned long t;

    do {

    t = (unsigned long) ((unsigned) buf[3] << 8 | buf[2]) << 16 |

        ((unsigned) buf[1] << 8 | buf[0]);

    *(unsigned long *) buf = t;

    buf += 4;

    } while (--longs);

}

#endif

#endif



/*

 * 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)

{

  unsigned long t;



    //Update bitcount 



    t = ctx->bits[0];

    if ((ctx->bits[0] = t + ((unsigned long) 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) {

        memcpy(p, buf, len);

        return;

    }

    memcpy(p, buf, t);

    byteReverse(ctx->in, 16);

    MD5Transform(ctx->buf, (unsigned long *) ctx->in);

    buf += t;

    len -= t;

    }

    // Process data in 64-byte chunks 



    while (len >= 64) {

    memcpy(ctx->in, buf, 64);

    byteReverse(ctx->in, 16);

    MD5Transform(ctx->buf, (unsigned long *) ctx->in);

    buf += 64;

    len -= 64;

    }



    // Handle any remaining bytes of data. 



    memcpy(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 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, (unsigned long *) 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 

    ((unsigned long *) ctx->in)[14] = ctx->bits[0];

    ((unsigned long *) ctx->in)[15] = ctx->bits[1];



    MD5Transform(ctx->buf, (unsigned long *) ctx->in);

    byteReverse((unsigned char *) ctx->buf, 4);

    memcpy(digest, ctx->buf, 16);

    memset(ctx, 0, sizeof(ctx));    // In case it's sensitive 

}



#ifndef ASM_MD5



/* 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(unsigned long buf[4], unsigned long const in[16])

{

    register unsigned long 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;

}



#endif

#ifndef MD5_H

#define MD5_H



#ifdef __alpha

typedef unsigned int uint32;

#else

typedef unsigned long uint32;

#endif



struct MD5Context {

    uint32 buf[4];

    uint32 bits[2];

    unsigned char in[64];

};



void MD5Init(struct MD5Context *context);

void MD5Update(struct MD5Context *context, unsigned char const *buf,

           unsigned len);

void MD5Final(unsigned char digest[16], struct MD5Context *context);

void MD5Transform(uint32 buf[4], uint32 const in[16]);



/*

 * This is needed to make RSAREF happy on some MS-DOS compilers.

 */

typedef struct MD5Context MD5_CTX;



#endif /* !MD5_H */