/*****************************************************************************/

/* md32.cpp                               Copyright (c) Ladislav Zezula 2007 */

/*---------------------------------------------------------------------------*/

/* Implementation of MD5                                                     */

/*---------------------------------------------------------------------------*/

/*   Date    Ver   Who  Comment                                              */

/* --------  ----  ---  -------                                              */

/* 11.06.07  1.00  Lad  The first version of md5.cpp                         */

/*****************************************************************************/



#include <string.h>

#include "md5.h"



/*

 * 32-bit integer manipulation macros (little endian)

 */

#ifndef GET_UINT32_LE

#define GET_UINT32_LE(n,b,i)                            \

{                                                       \

    (n) = ( (unsigned long) (b)[(i)    ]       )        \

        | ( (unsigned long) (b)[(i) + 1] <<  8 )        \

        | ( (unsigned long) (b)[(i) + 2] << 16 )        \

        | ( (unsigned long) (b)[(i) + 3] << 24 );       \

}

#endif

#ifndef PUT_UINT32_LE

#define PUT_UINT32_LE(n,b,i)                            \

{                                                       \

    (b)[(i)    ] = (unsigned char) ( (n)       );       \

    (b)[(i) + 1] = (unsigned char) ( (n) >>  8 );       \

    (b)[(i) + 2] = (unsigned char) ( (n) >> 16 );       \

    (b)[(i) + 3] = (unsigned char) ( (n) >> 24 );       \

}

#endif



void md5_process( md5_context *ctx, unsigned char data[64] )

{

    unsigned long X[16], A, B, C, D;



    GET_UINT32_LE( X[0],  data,  0 );

    GET_UINT32_LE( X[1],  data,  4 );

    GET_UINT32_LE( X[2],  data,  8 );

    GET_UINT32_LE( X[3],  data, 12 );

    GET_UINT32_LE( X[4],  data, 16 );

    GET_UINT32_LE( X[5],  data, 20 );

    GET_UINT32_LE( X[6],  data, 24 );

    GET_UINT32_LE( X[7],  data, 28 );

    GET_UINT32_LE( X[8],  data, 32 );

    GET_UINT32_LE( X[9],  data, 36 );

    GET_UINT32_LE( X[10], data, 40 );

    GET_UINT32_LE( X[11], data, 44 );

    GET_UINT32_LE( X[12], data, 48 );

    GET_UINT32_LE( X[13], data, 52 );

    GET_UINT32_LE( X[14], data, 56 );

    GET_UINT32_LE( X[15], data, 60 );



#define S(x,n) ((x << n) | ((x & 0xFFFFFFFF) >> (32 - n)))



#define P(a,b,c,d,k,s,t)                                \

{                                                       \

    a += F(b,c,d) + X[k] + t; a = S(a,s) + b;           \

}



    A = ctx->state[0];

    B = ctx->state[1];

    C = ctx->state[2];

    D = ctx->state[3];



#define F(x,y,z) (z ^ (x & (y ^ z)))



    P( A, B, C, D,  0,  7, 0xD76AA478 );

    P( D, A, B, C,  1, 12, 0xE8C7B756 );

    P( C, D, A, B,  2, 17, 0x242070DB );

    P( B, C, D, A,  3, 22, 0xC1BDCEEE );

    P( A, B, C, D,  4,  7, 0xF57C0FAF );

    P( D, A, B, C,  5, 12, 0x4787C62A );

    P( C, D, A, B,  6, 17, 0xA8304613 );

    P( B, C, D, A,  7, 22, 0xFD469501 );

    P( A, B, C, D,  8,  7, 0x698098D8 );

    P( D, A, B, C,  9, 12, 0x8B44F7AF );

    P( C, D, A, B, 10, 17, 0xFFFF5BB1 );

    P( B, C, D, A, 11, 22, 0x895CD7BE );

    P( A, B, C, D, 12,  7, 0x6B901122 );

    P( D, A, B, C, 13, 12, 0xFD987193 );

    P( C, D, A, B, 14, 17, 0xA679438E );

    P( B, C, D, A, 15, 22, 0x49B40821 );



#undef F



#define F(x,y,z) (y ^ (z & (x ^ y)))



    P( A, B, C, D,  1,  5, 0xF61E2562 );

    P( D, A, B, C,  6,  9, 0xC040B340 );

    P( C, D, A, B, 11, 14, 0x265E5A51 );

    P( B, C, D, A,  0, 20, 0xE9B6C7AA );

    P( A, B, C, D,  5,  5, 0xD62F105D );

    P( D, A, B, C, 10,  9, 0x02441453 );

    P( C, D, A, B, 15, 14, 0xD8A1E681 );

    P( B, C, D, A,  4, 20, 0xE7D3FBC8 );

    P( A, B, C, D,  9,  5, 0x21E1CDE6 );

    P( D, A, B, C, 14,  9, 0xC33707D6 );

    P( C, D, A, B,  3, 14, 0xF4D50D87 );

    P( B, C, D, A,  8, 20, 0x455A14ED );

    P( A, B, C, D, 13,  5, 0xA9E3E905 );

    P( D, A, B, C,  2,  9, 0xFCEFA3F8 );

    P( C, D, A, B,  7, 14, 0x676F02D9 );

    P( B, C, D, A, 12, 20, 0x8D2A4C8A );



#undef F

    

#define F(x,y,z) (x ^ y ^ z)



    P( A, B, C, D,  5,  4, 0xFFFA3942 );

    P( D, A, B, C,  8, 11, 0x8771F681 );

    P( C, D, A, B, 11, 16, 0x6D9D6122 );

    P( B, C, D, A, 14, 23, 0xFDE5380C );

    P( A, B, C, D,  1,  4, 0xA4BEEA44 );

    P( D, A, B, C,  4, 11, 0x4BDECFA9 );

    P( C, D, A, B,  7, 16, 0xF6BB4B60 );

    P( B, C, D, A, 10, 23, 0xBEBFBC70 );

    P( A, B, C, D, 13,  4, 0x289B7EC6 );

    P( D, A, B, C,  0, 11, 0xEAA127FA );

    P( C, D, A, B,  3, 16, 0xD4EF3085 );

    P( B, C, D, A,  6, 23, 0x04881D05 );

    P( A, B, C, D,  9,  4, 0xD9D4D039 );

    P( D, A, B, C, 12, 11, 0xE6DB99E5 );

    P( C, D, A, B, 15, 16, 0x1FA27CF8 );

    P( B, C, D, A,  2, 23, 0xC4AC5665 );



#undef F



#define F(x,y,z) (y ^ (x | ~z))



    P( A, B, C, D,  0,  6, 0xF4292244 );

    P( D, A, B, C,  7, 10, 0x432AFF97 );

    P( C, D, A, B, 14, 15, 0xAB9423A7 );

    P( B, C, D, A,  5, 21, 0xFC93A039 );

    P( A, B, C, D, 12,  6, 0x655B59C3 );

    P( D, A, B, C,  3, 10, 0x8F0CCC92 );

    P( C, D, A, B, 10, 15, 0xFFEFF47D );

    P( B, C, D, A,  1, 21, 0x85845DD1 );

    P( A, B, C, D,  8,  6, 0x6FA87E4F );

    P( D, A, B, C, 15, 10, 0xFE2CE6E0 );

    P( C, D, A, B,  6, 15, 0xA3014314 );

    P( B, C, D, A, 13, 21, 0x4E0811A1 );

    P( A, B, C, D,  4,  6, 0xF7537E82 );

    P( D, A, B, C, 11, 10, 0xBD3AF235 );

    P( C, D, A, B,  2, 15, 0x2AD7D2BB );

    P( B, C, D, A,  9, 21, 0xEB86D391 );



#undef F



    ctx->state[0] += A;

    ctx->state[1] += B;

    ctx->state[2] += C;

    ctx->state[3] += D;

}



/*

 * MD5 context setup

 */



void MD5_Init( md5_context *ctx )

{

    ctx->total[0] = 0;

    ctx->total[1] = 0;



    ctx->state[0] = 0x67452301;

    ctx->state[1] = 0xEFCDAB89;

    ctx->state[2] = 0x98BADCFE;

    ctx->state[3] = 0x10325476;

}



/*

 * MD5 process buffer

 */

void MD5_Update( md5_context *ctx, unsigned char *input, int ilen )

{

    int fill;

    unsigned long left;



    if( ilen <= 0 )

        return;



    left = ctx->total[0] & 0x3F;

    fill = 64 - left;



    ctx->total[0] += ilen;

    ctx->total[0] &= 0xFFFFFFFF;



    if( ctx->total[0] < (unsigned long) ilen )

        ctx->total[1]++;



    if( left && ilen >= fill )

    {

        memcpy( (void *) (ctx->buffer + left),

                (void *) input, fill );

        md5_process( ctx, ctx->buffer );

        input += fill;

        ilen  -= fill;

        left = 0;

    }



    while( ilen >= 64 )

    {

        md5_process( ctx, input );

        input += 64;

        ilen  -= 64;

    }



    if( ilen > 0 )

    {

        memcpy( (void *) (ctx->buffer + left),

                (void *) input, ilen );

    }

}



static const unsigned char md5_padding[64] =

{

 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0

};



/*

 * MD5 final digest

 */

void MD5_Finish( md5_context *ctx, unsigned char output[16] )

{

    unsigned long last, padn;

    unsigned long high, low;

    unsigned char msglen[8];



    high = ( ctx->total[0] >> 29 )

         | ( ctx->total[1] <<  3 );

    low  = ( ctx->total[0] <<  3 );



    PUT_UINT32_LE( low,  msglen, 0 );

    PUT_UINT32_LE( high, msglen, 4 );



    last = ctx->total[0] & 0x3F;

    padn = ( last < 56 ) ? ( 56 - last ) : ( 120 - last );



    MD5_Update( ctx, (unsigned char *) md5_padding, padn );

    MD5_Update( ctx, msglen, 8 );



    PUT_UINT32_LE( ctx->state[0], output,  0 );

    PUT_UINT32_LE( ctx->state[1], output,  4 );

    PUT_UINT32_LE( ctx->state[2], output,  8 );

    PUT_UINT32_LE( ctx->state[3], output, 12 );

}