View source for Md5.c

this is a simple md5 checksum program I found online.  I've been able to compile it on AmigaDOS, MS-DOS and Win32 environments.

== source ==

<pre>
/*
 **********************************************************************
 ** md5.h -- Header file for implementation of MD5                   **
 ** RSA Data Security, Inc. MD5 Message Digest Algorithm             **
 ** Created: 2/17/90 RLR                                             **
 ** Revised: 12/27/90 SRD,AJ,BSK,JT Reference C version              **
 ** Revised (for MD5): RLR 4/27/91                                   **
 **   -- G modified to have y&~z instead of y&z                      **
 **   -- FF, GG, HH modified to add in last register done            **
 **   -- Access pattern: round 2 works mod 5, round 3 works mod 3    **
 **   -- distinct additive constant for each step                    **
 **   -- round 4 added, working mod 7                                **
 **********************************************************************
 */

/*
 **********************************************************************
 ** 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.                                   **
 **********************************************************************
 */

/* typedef a 32 bit type */
typedef unsigned long int UINT4;

/* Data structure for MD5 (Message Digest) computation */
typedef struct {
  UINT4 i[2];                   /* number of _bits_ handled mod 2^64 */
  UINT4 buf[4];                                    /* scratch buffer */
  unsigned char in[64];                              /* input buffer */
  unsigned char digest[16];     /* actual digest after MD5Final call */
} MD5_CTX;

void MD5Init ();
void MD5Update ();
void MD5Final ();

/*
 **********************************************************************
 ** End of md5.h                                                     **
 ******************************* (cut) ********************************
 */

/*
 **********************************************************************
 ** md5.c                                                            **
 ** RSA Data Security, Inc. MD5 Message Digest Algorithm             **
 ** Created: 2/17/90 RLR                                             **
 ** Revised: 1/91 SRD,AJ,BSK,JT Reference C Version                  **
 **********************************************************************
 */

/*
 **********************************************************************
 ** 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.                                   **
 **********************************************************************
 */

/* -- include the following line if the md5.h header file is separate -- */
/* #include "md5.h" */

/* forward declaration */
static void Transform ();

static unsigned char 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 and H are basic MD5 functions: selection, majority, parity */
#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) + (UINT4)(ac); \
   (a) = ROTATE_LEFT ((a), (s)); \
   (a) += (b); \
  }
#define GG(a, b, c, d, x, s, ac) \
  {(a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \
   (a) = ROTATE_LEFT ((a), (s)); \
   (a) += (b); \
  }
#define HH(a, b, c, d, x, s, ac) \
  {(a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \
   (a) = ROTATE_LEFT ((a), (s)); \
   (a) += (b); \
  }
#define II(a, b, c, d, x, s, ac) \
  {(a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \
   (a) = ROTATE_LEFT ((a), (s)); \
   (a) += (b); \
  }

void MD5Init (mdContext)
MD5_CTX *mdContext;
{
  mdContext->i[0] = mdContext->i[1] = (UINT4)0;

  /* Load magic initialization constants.
   */
  mdContext->buf[0] = (UINT4)0x67452301;
  mdContext->buf[1] = (UINT4)0xefcdab89;
  mdContext->buf[2] = (UINT4)0x98badcfe;
  mdContext->buf[3] = (UINT4)0x10325476;
}

void MD5Update (mdContext, inBuf, inLen)
MD5_CTX *mdContext;
unsigned char *inBuf;
unsigned int inLen;
{
  UINT4 in[16];
  int mdi;
  unsigned int i, ii;

  /* compute number of bytes mod 64 */
  mdi = (int)((mdContext->i[0] >> 3) & 0x3F);

  /* update number of bits */
  if ((mdContext->i[0] + ((UINT4)inLen << 3)) < mdContext->i[0])
    mdContext->i[1]++;
  mdContext->i[0] += ((UINT4)inLen << 3);
  mdContext->i[1] += ((UINT4)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] = (((UINT4)mdContext->in[ii+3]) << 24) |
                (((UINT4)mdContext->in[ii+2]) << 16) |
                (((UINT4)mdContext->in[ii+1]) << 8) |
                ((UINT4)mdContext->in[ii]);
      Transform (mdContext->buf, in);
      mdi = 0;
    }
  }
}

void MD5Final (mdContext)
MD5_CTX *mdContext;
{
  UINT4 in[16];
  int mdi;
  unsigned int i, ii;
  unsigned int padLen;

  /* 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);
  MD5Update (mdContext, PADDING, padLen);

  /* append length in bits and transform */
  for (i = 0, ii = 0; i < 14; i++, ii += 4)
    in[i] = (((UINT4)mdContext->in[ii+3]) << 24) |
            (((UINT4)mdContext->in[ii+2]) << 16) |
            (((UINT4)mdContext->in[ii+1]) << 8) |
            ((UINT4)mdContext->in[ii]);
  Transform (mdContext->buf, in);

  /* store buffer in digest */
  for (i = 0, ii = 0; i < 4; i++, ii += 4) {
    mdContext->digest[ii] = (unsigned char)(mdContext->buf[i] & 0xFF);
    mdContext->digest[ii+1] =
      (unsigned char)((mdContext->buf[i] >> 8) & 0xFF);
    mdContext->digest[ii+2] =
      (unsigned char)((mdContext->buf[i] >> 16) & 0xFF);
    mdContext->digest[ii+3] =
      (unsigned char)((mdContext->buf[i] >> 24) & 0xFF);
  }
}

/* Basic MD5 step. Transform buf based on in.
 */
static void Transform (buf, in)
UINT4 *buf;
UINT4 *in;
{
  UINT4 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, 3614090360); /* 1 */
  FF ( d, a, b, c, in[ 1], S12, 3905402710); /* 2 */
  FF ( c, d, a, b, in[ 2], S13,  606105819); /* 3 */
  FF ( b, c, d, a, in[ 3], S14, 3250441966); /* 4 */
  FF ( a, b, c, d, in[ 4], S11, 4118548399); /* 5 */
  FF ( d, a, b, c, in[ 5], S12, 1200080426); /* 6 */
  FF ( c, d, a, b, in[ 6], S13, 2821735955); /* 7 */
  FF ( b, c, d, a, in[ 7], S14, 4249261313); /* 8 */
  FF ( a, b, c, d, in[ 8], S11, 1770035416); /* 9 */
  FF ( d, a, b, c, in[ 9], S12, 2336552879); /* 10 */
  FF ( c, d, a, b, in[10], S13, 4294925233); /* 11 */
  FF ( b, c, d, a, in[11], S14, 2304563134); /* 12 */
  FF ( a, b, c, d, in[12], S11, 1804603682); /* 13 */
  FF ( d, a, b, c, in[13], S12, 4254626195); /* 14 */
  FF ( c, d, a, b, in[14], S13, 2792965006); /* 15 */
  FF ( b, c, d, a, in[15], S14, 1236535329); /* 16 */

  /* Round 2 */
#define S21 5
#define S22 9
#define S23 14
#define S24 20
  GG ( a, b, c, d, in[ 1], S21, 4129170786); /* 17 */
  GG ( d, a, b, c, in[ 6], S22, 3225465664); /* 18 */
  GG ( c, d, a, b, in[11], S23,  643717713); /* 19 */
  GG ( b, c, d, a, in[ 0], S24, 3921069994); /* 20 */
  GG ( a, b, c, d, in[ 5], S21, 3593408605); /* 21 */
  GG ( d, a, b, c, in[10], S22,   38016083); /* 22 */
  GG ( c, d, a, b, in[15], S23, 3634488961); /* 23 */
  GG ( b, c, d, a, in[ 4], S24, 3889429448); /* 24 */
  GG ( a, b, c, d, in[ 9], S21,  568446438); /* 25 */
  GG ( d, a, b, c, in[14], S22, 3275163606); /* 26 */
  GG ( c, d, a, b, in[ 3], S23, 4107603335); /* 27 */
  GG ( b, c, d, a, in[ 8], S24, 1163531501); /* 28 */
  GG ( a, b, c, d, in[13], S21, 2850285829); /* 29 */
  GG ( d, a, b, c, in[ 2], S22, 4243563512); /* 30 */
  GG ( c, d, a, b, in[ 7], S23, 1735328473); /* 31 */
  GG ( b, c, d, a, in[12], S24, 2368359562); /* 32 */

  /* Round 3 */
#define S31 4
#define S32 11
#define S33 16
#define S34 23
  HH ( a, b, c, d, in[ 5], S31, 4294588738); /* 33 */
  HH ( d, a, b, c, in[ 8], S32, 2272392833); /* 34 */
  HH ( c, d, a, b, in[11], S33, 1839030562); /* 35 */
  HH ( b, c, d, a, in[14], S34, 4259657740); /* 36 */
  HH ( a, b, c, d, in[ 1], S31, 2763975236); /* 37 */
  HH ( d, a, b, c, in[ 4], S32, 1272893353); /* 38 */
  HH ( c, d, a, b, in[ 7], S33, 4139469664); /* 39 */
  HH ( b, c, d, a, in[10], S34, 3200236656); /* 40 */
  HH ( a, b, c, d, in[13], S31,  681279174); /* 41 */
  HH ( d, a, b, c, in[ 0], S32, 3936430074); /* 42 */
  HH ( c, d, a, b, in[ 3], S33, 3572445317); /* 43 */
  HH ( b, c, d, a, in[ 6], S34,   76029189); /* 44 */
  HH ( a, b, c, d, in[ 9], S31, 3654602809); /* 45 */
  HH ( d, a, b, c, in[12], S32, 3873151461); /* 46 */
  HH ( c, d, a, b, in[15], S33,  530742520); /* 47 */
  HH ( b, c, d, a, in[ 2], S34, 3299628645); /* 48 */

  /* Round 4 */
#define S41 6
#define S42 10
#define S43 15
#define S44 21
  II ( a, b, c, d, in[ 0], S41, 4096336452); /* 49 */
  II ( d, a, b, c, in[ 7], S42, 1126891415); /* 50 */
  II ( c, d, a, b, in[14], S43, 2878612391); /* 51 */
  II ( b, c, d, a, in[ 5], S44, 4237533241); /* 52 */
  II ( a, b, c, d, in[12], S41, 1700485571); /* 53 */
  II ( d, a, b, c, in[ 3], S42, 2399980690); /* 54 */
  II ( c, d, a, b, in[10], S43, 4293915773); /* 55 */
  II ( b, c, d, a, in[ 1], S44, 2240044497); /* 56 */
  II ( a, b, c, d, in[ 8], S41, 1873313359); /* 57 */
  II ( d, a, b, c, in[15], S42, 4264355552); /* 58 */
  II ( c, d, a, b, in[ 6], S43, 2734768916); /* 59 */
  II ( b, c, d, a, in[13], S44, 1309151649); /* 60 */
  II ( a, b, c, d, in[ 4], S41, 4149444226); /* 61 */
  II ( d, a, b, c, in[11], S42, 3174756917); /* 62 */
  II ( c, d, a, b, in[ 2], S43,  718787259); /* 63 */
  II ( b, c, d, a, in[ 9], S44, 3951481745); /* 64 */

  buf[0] += a;
  buf[1] += b;
  buf[2] += c;
  buf[3] += d;
}

/*
 **********************************************************************
 ** End of md5.c                                                     **
 ******************************* (cut) ********************************
 */

/*
 **********************************************************************
 ** md5driver.c -- sample routines to test                           **
 ** RSA Data Security, Inc. MD5 message digest algorithm.            **
 ** Created: 2/16/90 RLR                                             **
 ** Updated: 1/91 SRD                                                **
 **********************************************************************
 */

/*
 **********************************************************************
 ** Copyright (C) 1990, RSA Data Security, Inc. All rights reserved. **
 **                                                                  **
 ** 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.                                   **
 **********************************************************************
 */

#include <stdio.h>
#include <sys/types.h>
#include <time.h>
#include <string.h>
/* -- include the following file if the file md5.h is separate -- */
/* #include "md5.h" */

/* Prints message digest buffer in mdContext as 32 hexadecimal digits.
   Order is from low-order byte to high-order byte of digest.
   Each byte is printed with high-order hexadecimal digit first.
 */
static void MDPrint (mdContext)
MD5_CTX *mdContext;
{
  int i;

  for (i = 0; i < 16; i++)
    printf ("%02x", mdContext->digest[i]);
}

/* size of test block */
#define TEST_BLOCK_SIZE 1000

/* number of blocks to process */
#define TEST_BLOCKS 10000

/* number of test bytes = TEST_BLOCK_SIZE * TEST_BLOCKS */
static long TEST_BYTES = (long)TEST_BLOCK_SIZE * (long)TEST_BLOCKS;

/* A time trial routine, to measure the speed of MD5.
   Measures wall time required to digest TEST_BLOCKS * TEST_BLOCK_SIZE
   characters.
 */
static void MDTimeTrial ()
{
  MD5_CTX mdContext;
  time_t endTime, startTime;
  unsigned char data[TEST_BLOCK_SIZE];
  unsigned int i;

  /* initialize test data */
  for (i = 0; i < TEST_BLOCK_SIZE; i++)
    data[i] = (unsigned char)(i & 0xFF);

  /* start timer */
  printf ("MD5 time trial. Processing %ld characters...\n", TEST_BYTES);
  time (&startTime);

  /* digest data in TEST_BLOCK_SIZE byte blocks */
  MD5Init (&mdContext);
  for (i = TEST_BLOCKS; i > 0; i--)
    MD5Update (&mdContext, data, TEST_BLOCK_SIZE);
  MD5Final (&mdContext);

  /* stop timer, get time difference */
  time (&endTime);
  MDPrint (&mdContext);
  printf (" is digest of test input.\n");
  printf
    ("Seconds to process test input: %ld\n", (long)(endTime-startTime));
  printf
    ("Characters processed per second: %ld\n",
     TEST_BYTES/(endTime-startTime));
}

/* Computes the message digest for string inString.
   Prints out message digest, a space, the string (in quotes) and a
   carriage return.
 */
static void MDString (inString)
char *inString;
{
  MD5_CTX mdContext;
  unsigned int len = strlen (inString);

  MD5Init (&mdContext);
  MD5Update (&mdContext, inString, len);
  MD5Final (&mdContext);
  MDPrint (&mdContext);
  printf (" \"%s\"\n\n", inString);
}

/* Computes the message digest for a specified file.
   Prints out message digest, a space, the file name, and a carriage
   return.
 */
static void MDFile (filename)
char *filename;
{
  FILE *inFile = fopen (filename, "rb");
  MD5_CTX mdContext;
  int bytes;
  unsigned char data[1024];

  if (inFile == NULL) {
    printf ("%s can't be opened.\n", filename);
    return;
  }

  MD5Init (&mdContext);
  while ((bytes = fread (data, 1, 1024, inFile)) != 0)
    MD5Update (&mdContext, data, bytes);
  MD5Final (&mdContext);
  MDPrint (&mdContext);
  printf (" %s\n", filename);
  fclose (inFile);
}

/* Writes the message digest of the data from stdin onto stdout,
   followed by a carriage return.
 */
static void MDFilter ()
{
  MD5_CTX mdContext;
  int bytes;
  unsigned char data[16];

  MD5Init (&mdContext);
  while ((bytes = fread (data, 1, 16, stdin)) != 0)
    MD5Update (&mdContext, data, bytes);
  MD5Final (&mdContext);
  MDPrint (&mdContext);
  printf ("\n");
}

/* Runs a standard suite of test data.
 */
static void MDTestSuite ()
{
  printf ("MD5 test suite results:\n\n");
  MDString ("");
  MDString ("a");
  MDString ("abc");
  MDString ("message digest");
  MDString ("abcdefghijklmnopqrstuvwxyz");
  MDString
    ("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789");
  MDString
    ("1234567890123456789012345678901234567890\
1234567890123456789012345678901234567890");
  /* Contents of file foo are "abc" */
  MDFile ("foo");
}

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

  /* For each command line argument in turn:
  ** filename          -- prints message digest and name of file
  ** -sstring          -- prints message digest and contents of string
  ** -t                -- prints time trial statistics for 1M characters
  ** -x                -- execute a standard suite of test data
  ** (no args)         -- writes messages digest of stdin onto stdout
  */
  if (argc == 1)
    MDFilter ();
  else
    for (i = 1; i < argc; i++)
      if (argv[i][0] == '-' && argv[i][1] == 's')
        MDString (argv[i] + 2);
      else if (strcmp (argv[i], "-t") == 0)
        MDTimeTrial ();
      else if (strcmp (argv[i], "-x") == 0)
        MDTestSuite ();
      else MDFile (argv[i]);
}

/*
 **********************************************************************
 ** End of md5driver.c                                               **
 ******************************* (cut) ********************************
 */
</pre>