md5

/* 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 ();

/* 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 ( 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 ( 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;
        } // end if
    } // end while
}

void MD5Final ( 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 );
    } // end for
}

/* Basic MD5 step. Transform buf based on in.
 */
static void Transform ( 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;
}


#include <stdio.h>
#include <sys/types.h>
#include <time.h>
#include <string.h>


static void MDPrint ( 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 ( 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 ( 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 ( "12345678901234567890123456789012345678901234567890123456789012345678901234567890" );
    /* Contents of file foo are "abc" */
    MDFile ( "foo" );
}

int main ( 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 打印消息摘要和字符串内容
    ** -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 for
    } // end else

    return 1;
}