MD5算法的C代码实现及测试

本程序主要是通过 rfc1321.txt 整理而来。这个文件可以在下面的地址下载。

 

http://www.ietf.org/rfc/rfc1321.txt

 

本程序在VC 2003 .NET 和 Dev C++ 4.9  下编译通过。

 

#include <stdio.h>

typedef struct {

    unsigned int state[4];     

    unsigned int count[2];     

    unsigned char buffer[64];     

} MD5Context;

 

void MD5_Init(MD5Context * context);

void MD5_Update(MD5Context * context, unsigned char * buf, int len);

void MD5_Final(MD5Context * context, unsigned char digest[16]);

#define S11 7

#define S12 12

#define S13 17

#define S14 22

#define S21 5

#define S22 9

#define S23 14

#define S24 20

#define S31 4

#define S32 11

#define S33 16

#define S34 23

#define S41 6

#define S42 10

#define S43 15

#define S44 21

 

static unsigned char 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

};

#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)))

 

#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))

 

#define FF(a, b, c, d, x, s, ac)          /

    {                       /

    (a) += F((b), (c), (d)) + (x) + (unsigned int)(ac);  /

    (a) = ROTATE_LEFT((a), (s));           /

    (a) += (b);                 /

    }

 

#define GG(a, b, c, d, x, s, ac)          /

    {                       /

    (a) += G((b), (c), (d)) + (x) + (unsigned int)(ac);  /

    (a) = ROTATE_LEFT((a), (s));           /

    (a) += (b);                 /

    }

 

#define HH(a, b, c, d, x, s, ac)          /

    {                       /

    (a) += H((b), (c), (d)) + (x) + (unsigned int)(ac);  /

    (a) = ROTATE_LEFT((a), (s));           /

    (a) += (b);                 /

    }

 

#define II(a, b, c, d, x, s, ac)          /

    {                       /

    (a) += I((b), (c), (d)) + (x) + (unsigned int)(ac);  /

    (a) = ROTATE_LEFT((a), (s));           /

    (a) += (b);                 /

    }

static void MD5_Encode(unsigned char * output, unsigned int * input, int len)

{

    unsigned int i, j;

 

    for (i = 0, j = 0; j < len; i++, j += 4)

    {

       output[j] = (unsigned char) (input[i] & 0xff);

       output[j + 1] = (unsigned char) ((input[i] >> 8) & 0xff);

       output[j + 2] = (unsigned char) ((input[i] >> 16) & 0xff);

       output[j + 3] = (unsigned char) ((input[i] >> 24) & 0xff);

    }

}

 

static void MD5_Decode(unsigned int * output, unsigned char * input, int len)

{

    unsigned int i, j;

 

    for (i = 0, j = 0; j < len; i++, j += 4)

    {

       output[i] = ((unsigned int) input[j]) |

           (((unsigned int) input[j + 1]) << 8) |

           (((unsigned int) input[j + 2]) << 16) |

           (((unsigned int) input[j + 3]) << 24);

    }

}

 

static void MD5_Transform(unsigned int state[4], unsigned char block[64])

{

    unsigned int a = state[0], b = state[1], c = state[2], d = state[3], x[16];

 

    MD5_Decode(x, block, 64);

 

    /* Round 1 */

    FF(a, b, c, d, x[0], S11, 0xd76aa478);    /* 1 */

    FF(d, a, b, c, x[1], S12, 0xe8c7b756);    /* 2 */

    FF(c, d, a, b, x[2], S13, 0x242070db);    /* 3 */

    FF(b, c, d, a, x[3], S14, 0xc1bdceee);    /* 4 */

    FF(a, b, c, d, x[4], S11, 0xf57c0faf);    /* 5 */

    FF(d, a, b, c, x[5], S12, 0x4787c62a);    /* 6 */

    FF(c, d, a, b, x[6], S13, 0xa8304613);    /* 7 */

    FF(b, c, d, a, x[7], S14, 0xfd469501);    /* 8 */

    FF(a, b, c, d, x[8], S11, 0x698098d8);    /* 9 */

    FF(d, a, b, c, x[9], S12, 0x8b44f7af);    /* 10 */

    FF(c, d, a, b, x[10], S13, 0xffff5bb1);   /* 11 */

    FF(b, c, d, a, x[11], S14, 0x895cd7be);   /* 12 */

    FF(a, b, c, d, x[12], S11, 0x6b901122);   /* 13 */

    FF(d, a, b, c, x[13], S12, 0xfd987193);   /* 14 */

    FF(c, d, a, b, x[14], S13, 0xa679438e);   /* 15 */

    FF(b, c, d, a, x[15], S14, 0x49b40821);   /* 16 */

 

    /* Round 2 */

    GG(a, b, c, d, x[1], S21, 0xf61e2562);    /* 17 */

    GG(d, a, b, c, x[6], S22, 0xc040b340);    /* 18 */

    GG(c, d, a, b, x[11], S23, 0x265e5a51);   /* 19 */

    GG(b, c, d, a, x[0], S24, 0xe9b6c7aa);    /* 20 */

    GG(a, b, c, d, x[5], S21, 0xd62f105d);    /* 21 */

    GG(d, a, b, c, x[10], S22, 0x2441453);    /* 22 */

    GG(c, d, a, b, x[15], S23, 0xd8a1e681);   /* 23 */

    GG(b, c, d, a, x[4], S24, 0xe7d3fbc8);    /* 24 */

    GG(a, b, c, d, x[9], S21, 0x21e1cde6);    /* 25 */

    GG(d, a, b, c, x[14], S22, 0xc33707d6);   /* 26 */

    GG(c, d, a, b, x[3], S23, 0xf4d50d87);    /* 27 */

    GG(b, c, d, a, x[8], S24, 0x455a14ed);    /* 28 */

    GG(a, b, c, d, x[13], S21, 0xa9e3e905);   /* 29 */

    GG(d, a, b, c, x[2], S22, 0xfcefa3f8);    /* 30 */

    GG(c, d, a, b, x[7], S23, 0x676f02d9);    /* 31 */

    GG(b, c, d, a, x[12], S24, 0x8d2a4c8a);   /* 32 */

 

    /* Round 3 */

    HH(a, b, c, d, x[5], S31, 0xfffa3942);    /* 33 */

    HH(d, a, b, c, x[8], S32, 0x8771f681);    /* 34 */

    HH(c, d, a, b, x[11], S33, 0x6d9d6122);   /* 35 */

    HH(b, c, d, a, x[14], S34, 0xfde5380c);   /* 36 */

    HH(a, b, c, d, x[1], S31, 0xa4beea44);    /* 37 */

    HH(d, a, b, c, x[4], S32, 0x4bdecfa9);    /* 38 */

    HH(c, d, a, b, x[7], S33, 0xf6bb4b60);    /* 39 */

    HH(b, c, d, a, x[10], S34, 0xbebfbc70);   /* 40 */

    HH(a, b, c, d, x[13], S31, 0x289b7ec6);   /* 41 */

    HH(d, a, b, c, x[0], S32, 0xeaa127fa);    /* 42 */

    HH(c, d, a, b, x[3], S33, 0xd4ef3085);    /* 43 */

    HH(b, c, d, a, x[6], S34, 0x4881d05); /* 44 */

    HH(a, b, c, d, x[9], S31, 0xd9d4d039);    /* 45 */

    HH(d, a, b, c, x[12], S32, 0xe6db99e5);   /* 46 */

    HH(c, d, a, b, x[15], S33, 0x1fa27cf8);   /* 47 */

    HH(b, c, d, a, x[2], S34, 0xc4ac5665);    /* 48 */

 

    /* Round 4 */

    II(a, b, c, d, x[0], S41, 0xf4292244);    /* 49 */

    II(d, a, b, c, x[7], S42, 0x432aff97);    /* 50 */

    II(c, d, a, b, x[14], S43, 0xab9423a7);   /* 51 */

    II(b, c, d, a, x[5], S44, 0xfc93a039);    /* 52 */

    II(a, b, c, d, x[12], S41, 0x655b59c3);   /* 53 */

    II(d, a, b, c, x[3], S42, 0x8f0ccc92);    /* 54 */

    II(c, d, a, b, x[10], S43, 0xffeff47d);   /* 55 */

    II(b, c, d, a, x[1], S44, 0x85845dd1);    /* 56 */

    II(a, b, c, d, x[8], S41, 0x6fa87e4f);    /* 57 */

    II(d, a, b, c, x[15], S42, 0xfe2ce6e0);   /* 58 */

    II(c, d, a, b, x[6], S43, 0xa3014314);    /* 59 */

    II(b, c, d, a, x[13], S44, 0x4e0811a1);   /* 60 */

    II(a, b, c, d, x[4], S41, 0xf7537e82);    /* 61 */

    II(d, a, b, c, x[11], S42, 0xbd3af235);   /* 62 */

    II(c, d, a, b, x[2], S43, 0x2ad7d2bb);    /* 63 */

    II(b, c, d, a, x[9], S44, 0xeb86d391);    /* 64 */

 

    state[0] += a;

    state[1] += b;

    state[2] += c;

    state[3] += d;

 

    memset((char *) x, 0, sizeof(x));

}

 

void MD5_Init(MD5Context * context)

{

    context->count[0] = context->count[1] = 0;

 

    context->state[0] = 0x67452301;

    context->state[1] = 0xefcdab89;

    context->state[2] = 0x98badcfe;

    context->state[3] = 0x10325476;

}

 

void MD5_Update(MD5Context * context, unsigned char * buf, int len)

{

    unsigned int i, index, partLen;

 

    index = (unsigned int) ((context->count[0] >> 3) & 0x3F);

 

    if ((context->count[0] += ((unsigned int) len << 3)) < ((unsigned int) len << 3))

    context->count[1]++;

    context->count[1] += ((unsigned int) len >> 29);

 

    partLen = 64 - index;

 

    if (len >= partLen)

    {

       memcpy((char *) &context->buffer[index], (char *) buf, partLen);

       MD5_Transform(context->state, context->buffer);

 

       for (i = partLen; i + 63 < len; i += 64)

           MD5_Transform(context->state, &buf[i]);

 

       index = 0;

    }

    else

    {

        i = 0;

    }

 

    memcpy((char *) &context->buffer[index], (char *) &buf[i], len - i);

}

 

void MD5_Final(MD5Context * context, unsigned char digest[16])

{

    unsigned char bits[8];

    unsigned int index, padLen;

 

    MD5_Encode(bits, context->count, 8);

 

    index = (unsigned int) ((context->count[0] >> 3) & 0x3f);

    padLen = (index < 56) ? (56 - index) : (120 - index);

    MD5_Update(context, PADDING, padLen);

 

    MD5_Update(context, bits, 8);

 

    MD5_Encode(digest, context->state, 16);

 

    memset((char *) context, 0, sizeof(*context));

}

void MD5_File (char * filename)

{

    FILE *file;

    MD5Context context;

    unsigned char buff[16];

    int i,len;

    unsigned char buffer[0x0400];

 

    if (!(file = fopen (filename, "rb")))

       printf ("%s can't be opened/n", filename);

    else

    {

       MD5_Init (&context);

       while (len = fread (buffer, 1, 1024, file))

           MD5_Update (&context, buffer, len);

       MD5_Final(&context,buff);

       fclose (file);

       for(i=0;i<16;i++)

       {

           printf("%x",(buff[i] & 0xF0)>>4);

           printf("%x",buff[i] & 0x0F);

       }

       printf("/n");

    }

}

int main()

{

    int i =0,j,len,startTime,endTime;

    MD5Context context;

    unsigned char buff[16];

   

    char * str1 = "";

    char * str2 = "abc";

    char * str3 = "message digest";

    char * str4 = "abcdefghijklmnopqrstuvwxyz";

    char * str5 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";

    char * str6 = "12345678901234567890123456789012345678901234567890123456789012345678901234567890";

   

    char str[7][100] =

    {

       "",

       "a",

       "abc",

       "message digest",

       "abcdefghijklmnopqrstuvwxyz",

       "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789",

       "12345678901234567890123456789012345678901234567890123456789012345678901234567890"

    };

    for(i=0;i<6;i++)

    {

       len = strlen(str[i]);

       MD5_Init(&context);

       MD5_Update(&context,(unsigned char *)str[i], len);

       MD5_Final(&context,buff);

       printf("MD5(/"%s/") = /n",str[i]);

       for(j=0;j<16;j++)

       {

           printf("%x",(buff[j] & 0xF0)>>4);

           printf("%x",buff[j] & 0x0F);

       }

       printf("/n***********************************************************/n");

    }

    printf("Wating.../n");

    MD5_File("00.dat");

    system("pause");

    return 0;

}