MD5密碼編譯演算法（c語言實現）

md5.h檔案

/*md5.hauthor mwater.www.epopsoft.com */#ifndef _MD5_H_#define _MD5_H_#include <memory.h>#define R_memset(x, y, z) memset(x, y, z)#define R_memcpy(x, y, z) memcpy(x, y, z)#define R_memcmp(x, y, z) memcmp(x, y, z)typedef unsigned long UINT4;typedef unsigned char *POINTER;/* MD5 context. */typedef struct {/* state (ABCD) */   /*四個32bits數，用於存放最終計算得到的訊息摘要。當訊息長度〉512bits時，也用於存放每個512bits的中間結果*/ UINT4 state[4];   /* number of bits, modulo 2^64 (lsb first) */    /*儲存原始資訊的bits數長度,不包括填充的bits，最長為 2^64 bits，因為2^64是一個64位元的最大值*/UINT4 count[2];/* input buffer */ /*存放輸入的資訊的緩衝區，512bits*/unsigned char buffer[64];  } MD5_CTX;unsigned char * mi_md5(unsigned char * content ,int len ,unsigned char  * md5_res/*the length of md5_res must be more than 16 Bytes*/ );#endif /* _MD5_H_ */

md5.cpp檔案

/*    md5.cpp   */#include "md5.h"/* Constants for MD5Transform routine. *//*md5轉換用到的常量，演算法本身規定的*/#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 21static void MD5Transform(UINT4 [4], unsigned char [64]);static void Encode(unsigned char *, UINT4 *, unsigned int);static void Decode(UINT4 *, unsigned char *, unsigned int);/*用於bits填充的緩衝區，為什麼要64個位元組呢？因為當欲加密的資訊的bits數被512除其餘數為448時，需要填充的bits的最大值為512=64*8 。*/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};/*接下來的這幾個宏定義是md5演算法規定的，就是對資訊進行md5加密都要做的運算。據說有經驗的高手跟蹤程式時根據這幾個特殊的操作就可以斷定是不是用的md5*//* F, G, H and I are basic MD5 functions.*/#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); \}/* MD5 initialization. Begins an MD5 operation, writing a new context. *//*初始化md5的結構*/static void MD5Init (MD5_CTX *context){/*將當前的有效資訊的長度設成0,這個很簡單,還沒有有效資訊,長度當然是0了*/context->count[0] = context->count[1] = 0;/* Load magic initialization constants.*//*初始化連結變數，演算法要求這樣，這個沒法解釋了*/context->state[0] = 0x67452301;context->state[1] = 0xefcdab89;context->state[2] = 0x98badcfe;context->state[3] = 0x10325476;}/* MD5 block update operation. Continues an MD5 message-digestoperation, processing another message block, and updating thecontext. *//*將與加密的資訊傳遞給md5結構，可以多次調用context：初始化過了的md5結構input：欲加密的資訊，可以任意長inputLen：指定input的長度*/static void MD5Update(MD5_CTX *context,unsigned char * input,unsigned int  inputLen){unsigned int i, index, partLen;/* Compute number of bytes mod 64 *//*計算已有資訊的bits長度的位元組數的模64, 64bytes=512bits。用於判斷已有資訊加上當前傳過來的資訊的總長度能不能達到512bits，如果能夠達到則對湊夠的512bits進行一次處理*/index = (unsigned int)((context->count[0] >> 3) & 0x3F);/* Update number of bits *//*更新已有資訊的bits長度*/if((context->count[0] += ((UINT4)inputLen << 3)) < ((UINT4)inputLen << 3))context->count[1]++;context->count[1] += ((UINT4)inputLen >> 29);/*計算已有的位元組數長度還差多少位元組可以 湊成64的整倍數*/partLen = 64 - index;/* Transform as many times as possible.*//*如果當前輸入的位元組數 大於 已有位元組數長度補足64位元組整倍數所差的位元組數*/if(inputLen >= partLen) {/*用當前輸入的內容把context->buffer的內容補足512bits*/R_memcpy((POINTER)&context->buffer[index], (POINTER)input, partLen);/*用基本函數對填充滿的512bits（已經儲存到context->buffer中） 做一次轉換，轉換結果儲存到context->state中*/MD5Transform(context->state, context->buffer);/*對當前輸入的剩餘位元組做轉換（如果剩餘的位元組<在輸入的input緩衝區中>大於512bits的話 ），轉換結果儲存到context->state中*/for(i = partLen; i + 63 < inputLen; i += 64)/*把i+63<inputlen改為i+64<=inputlen更容易理解*/MD5Transform(context->state, &input[i]);index = 0;}elsei = 0;/* Buffer remaining input *//*將輸入緩衝區中的不足填充滿512bits的剩餘內容填充到context->buffer中，留待以後再作處理*/R_memcpy((POINTER)&context->buffer[index], (POINTER)&input[i], inputLen-i);}/* MD5 finalization. Ends an MD5 message-digest operation, writing thethe message digest and zeroizing the context. *//*擷取加密 的最終結果digest：儲存最終的加密串context：你前面初始化並填入了資訊的md5結構*/static void MD5Final (unsigned char digest[16],MD5_CTX *context){unsigned char bits[8];unsigned int index, padLen;/* Save number of bits *//*將要被轉換的資訊(所有的)的bits長度拷貝到bits中*/Encode(bits, context->count, 8);/* Pad out to 56 mod 64. *//* 計算所有的bits長度的位元組數的模64, 64bytes=512bits*/index = (unsigned int)((context->count[0] >> 3) & 0x3f);/*計算需要填充的位元組數，padLen的取值範圍在1-64之間*/padLen = (index < 56) ? (56 - index) : (120 - index);/*這一次函數調用絕對不會再導致MD5Transform的被調用，因為這一次不會填滿512bits*/MD5Update(context, PADDING, padLen);/* Append length (before padding) *//*補上原始資訊的bits長度（bits長度固定的用64bits表示），這一次能夠恰巧湊夠512bits，不會多也不會少*/MD5Update(context, bits, 8);/* Store state in digest *//*將最終的結果儲存到digest中。ok，終於大功告成了*/Encode(digest, context->state, 16);/* Zeroize sensitive information. */R_memset((POINTER)context, 0, sizeof(*context));}/* MD5 basic transformation. Transforms state based on block. *//*對512bits資訊(即block緩衝區)進行一次處理，每次處理包括四輪state[4]：md5結構中的state[4]，用於儲存對512bits資訊加密的中間結果或者最終結果block[64]：欲加密的512bits資訊*/static void MD5Transform (UINT4 state[4], unsigned char block[64]){UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];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;/* Zeroize sensitive information. */R_memset((POINTER)x, 0, sizeof(x));}/* Encodes input (UINT4) into output (unsigned char). Assumes len isa multiple of 4. *//*將4位元組的整數copy到字元形式的緩衝區中output：用於輸出的字元緩衝區input：欲轉換的四位元組的整數形式的數組len：output緩衝區的長度，要求是4的整數倍*/static void Encode(unsigned char *output, UINT4 *input,unsigned 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);}}/* Decodes input (unsigned char) into output (UINT4). Assumes len isa multiple of 4. *//*與上面的函數正好相反，這一個把字元形式的緩衝區中的資料copy到4位元組的整數中（即以整數形式儲存）output：儲存轉換出的整數input：欲轉換的字元緩衝區len：輸入的字元緩衝區的長度，要求是4的整數倍*/static void Decode(UINT4 *output, unsigned char *input,unsigned int  len){unsigned int i, j;for(i = 0, j = 0; j < len; i++, j += 4)output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |(((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);}unsigned char * mi_md5(unsigned char * content ,int len ,unsigned char  * md5_res/*the length of md5_res must be more than 16 Bytes*/ ){MD5_CTX md5Ctx;MD5Init(&md5Ctx);MD5Update(&md5Ctx, content, len);MD5Final(md5_res, &md5Ctx);return md5_res ;}

typedef unsigned char mi_u_char ;

 mi_u_char * mi_md5(unsigned char * content ,int len ,unsigned char  * md5_res/*the length of md5_res must be more than 16 Bytes*/ ){if(!md5_res || NULL==content){return NULL ;}MD5_CTX md5Ctx;MD5Init(&md5Ctx);MD5Update(&md5Ctx, content, len);MD5Final(md5_res, &md5Ctx);return md5_res ;}mi_u_char * mi_md5_hex32(unsigned char * content ,int len ,unsigned char  * md532_res/*the length of md5_res must be more than 32 Bytes*/ ){mi_int i=0;unsigned char md5final[16];mi_md5(content,len ,md5final) ;int n= 0;for (i=0; i<16; i++) {n+=sprintf((char*)md532_res + n,"%02x", md5final[i]);}return md532_res ;}

main.cpp使用樣本

#include "md5.h"#include <stdio.h>#include <stdlib.h>#include <string.h>int main(){char m_strMd5[128];int i=0;memset(m_strMd5,0,sizeof(m_strMd5)) ;unsigned char md5final[16];mi_md5((unsigned char *)"123456",6,md5final) ;for (i=0; i<16; i++) {sprintf(m_strMd5,"%s%02x",m_strMd5, md5final[i]);}printf("%s",m_strMd5);system("pause");return 0;}