在C语言中实现MD5算法

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*/

#ifndef PROTOTYPES

#define PROTOTYPES 0

#endif

typedef unsigned char *POINTER;

typedef unsigned short int UINT2;

typedef unsigned long int UINT4;

#if PROTOTYPES

#define PROTO_LIST(list) list

#else

#define PROTO_LIST(list) ()

#endif

—————————— MD5.h————————————————————————————

typedef struct {

UINT4 state[4];

UINT4 count[2];

unsigned char buffer[64];

} MD5_CTX;

void MD5Init PROTO_LIST ((MD5_CTX *));

void MD5Update PROTO_LIST

((MD5_CTX *, unsigned char *, unsigned int));

void MD5Final PROTO_LIST ((unsigned char [16], MD5_CTX *));

※※※※※※※※※MD5C.C※※※※※※※※※※※※※※※※※※※※※※※※

#include "global.h"

#include "md5.h"

#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 void MD5Transform PROTO_LIST ((UINT4 [4], unsigned char [64]));

static void Encode PROTO_LIST

((unsigned char *, UINT4 *, unsigned int));

static void Decode PROTO_LIST

((UINT4 *, unsigned char *, unsigned int));

static void MD5_memcpy PROTO_LIST ((POINTER, POINTER, unsigned int));

static void MD5_memset PROTO_LIST ((POINTER, int, unsigned int));

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

};

/* 定义F G H I 为四个基数

#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) + (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); \

}

/*开始进行MD5计算

void MD5Init (context)

MD5_CTX *context;

{

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

/* 在这里定义四个常数，也就是我们刚才讲到的四个特征数.

context->state[0] = 0x67452301;

context->state[1] = 0xefcdab89;

context->state[2] = 0x98badcfe;

context->state[3] = 0x10325476;

}

void MD5Update (context, input, inputLen)

MD5_CTX *context;

unsigned char *input;                       &nbs