密码知识系列之基于C++的MD5算法类

MD5算法接收任意长的一个字符串,然后将它散列成128位的编码.它在各种加密,特别是消息摘要中用处非常的大

//"md5.h"

[align=left]#ifndef _LGY_MD5_H[/align]
[align=left]#define _LGY_MD5_H[/align]
[align=left] [/align]
[align=left]/* MD5 Class. */[/align]
[align=left]class MD5_CTX {[/align]
[align=left]public:[/align]
[align=left] MD5_CTX();[/align]
[align=left]virtual ~MD5_CTX();[/align]
[align=left]void MD5Update ( unsignedchar *input, unsignedint inputLen);[/align]
[align=left]void MD5Final (unsignedchar digest[16]);[/align]
[align=left] [/align]
[align=left]private:[/align]
[align=left]unsignedlongint state[4]; /* state (ABCD) */[/align]
[align=left]unsignedlongint count[2]; /* number of bits, modulo 2^64 (lsb first) */[/align]
[align=left]unsignedchar buffer[64]; /* input buffer */[/align]
[align=left]unsignedchar PADDING[64]; /* What? */[/align]
[align=left] [/align]
[align=left]private:[/align]
[align=left]void MD5Init ();[/align]
[align=left]void MD5Transform (unsignedlongint state[4], unsignedchar block[64]);[/align]
[align=left]void MD5_memcpy (unsignedchar* output, unsignedchar* input,unsignedint len);[/align]
[align=left]void Encode (unsignedchar *output, unsignedlongint *input,unsignedint len);[/align]
[align=left]void Decode (unsignedlongint *output, unsignedchar *input, unsignedint len);[/align]
[align=left]void MD5_memset (unsignedchar* output,int value,unsignedint len);[/align]
[align=left]};[/align]
[align=left] [/align]
[align=left]#endif[/align]
[align=left] [/align]
[align=left]//md5 cpp[/align]
[align=left] [/align]
[align=left]#include"md5.h"[/align]
[align=left] [/align]
[align=left]/* Constants for MD5Transform routine.[/align]
[align=left]*/[/align]
[align=left]#define S11 7[/align]
[align=left]#define S12 12[/align]
[align=left]#define S13 17[/align]
[align=left]#define S14 22[/align]
[align=left]#define S21 5[/align]
[align=left]#define S22 9[/align]
[align=left]#define S23 14[/align]
[align=left]#define S24 20[/align]
[align=left]#define S31 4[/align]
[align=left]#define S32 11[/align]
[align=left]#define S33 16[/align]
[align=left]#define S34 23[/align]
[align=left]#define S41 6[/align]
[align=left]#define S42 10[/align]
[align=left]#define S43 15[/align]
[align=left]#define S44 21[/align]
[align=left] [/align]
[align=left]/* F, G, H and I are basic MD5 functions.[/align]
[align=left]*/[/align]
[align=left]#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))[/align]
[align=left]#define G(x, y, z) (((x) & (z)) | ((y) & (~z)))[/align]
[align=left]#define H(x, y, z) ((x) ^ (y) ^ (z))[/align]
[align=left]#define I(x, y, z) ((y) ^ ((x) | (~z)))[/align]
[align=left] [/align]
[align=left]/* ROTATE_LEFT rotates x left n bits.[/align]
[align=left]*/[/align]
[align=left]#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))[/align]
[align=left] [/align]
[align=left]/* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.[/align]
[align=left]Rotation is separate from addition to prevent recomputation.[/align]
[align=left]*/[/align]
[align=left]#define FF(a, b, c, d, x, s, ac) { /[/align]
[align=left] (a) += F ((b), (c), (d)) + (x) + (unsignedlongint)(ac); /[/align]
[align=left] (a) = ROTATE_LEFT ((a), (s)); /[/align]
[align=left] (a) += (b); /[/align]
[align=left] }[/align]
[align=left]#define GG(a, b, c, d, x, s, ac) { /[/align]
[align=left] (a) += G ((b), (c), (d)) + (x) + (unsignedlongint)(ac); /[/align]
[align=left] (a) = ROTATE_LEFT ((a), (s)); /[/align]
[align=left] (a) += (b); /[/align]
[align=left] }[/align]
[align=left]#define HH(a, b, c, d, x, s, ac) { /[/align]
[align=left] (a) += H ((b), (c), (d)) + (x) + (unsignedlongint)(ac); /[/align]
[align=left] (a) = ROTATE_LEFT ((a), (s)); /[/align]
[align=left] (a) += (b); /[/align]
[align=left] }[/align]
[align=left]#define II(a, b, c, d, x, s, ac) { /[/align]
[align=left] (a) += I ((b), (c), (d)) + (x) + (unsignedlongint)(ac); /[/align]
[align=left] (a) = ROTATE_LEFT ((a), (s)); /[/align]
[align=left] (a) += (b); /[/align]
[align=left] }[/align]
[align=left] [/align]
[align=left] [/align]
[align=left]/* MD5 initialization. Begins an MD5 operation, writing a new context.[/align]
[align=left]*/[/align]
[align=left] [/align]
[align=left]MD5_CTX::MD5_CTX()[/align]
[align=left]{[/align]
[align=left] MD5Init ();[/align]
[align=left]}[/align]
[align=left] [/align]
[align=left]MD5_CTX::~MD5_CTX()[/align]
[align=left]{[/align]
[align=left]}[/align]
[align=left] [/align]
[align=left]void MD5_CTX::MD5Init ()[/align]
[align=left]{[/align]
[align=left]this->count[0] = this->count[1] = 0;[/align]
[align=left]/* Load magic initialization constants.*/[/align]
[align=left]/*this->state[0] = 0x67452301;[/align]
[align=left] this->state[1] = 0xefcdab89;[/align]
[align=left] this->state[2] = 0x98badcfe;[/align]
[align=left] this->state[3] = 0x10325476;*/[/align]
[align=left]this->state[0] = 0x01234567;[/align]
[align=left]this->state[1] = 0x89abcdef;[/align]
[align=left]this->state[2] = 0xfedcba98;[/align]
[align=left]this->state[3] = 0x76543210;[/align]
[align=left]/* Add by Liguangyi */[/align]
[align=left] MD5_memset(PADDING, 0, sizeof(PADDING));[/align]
[align=left] *PADDING=0x80;[/align]
[align=left]}[/align]
[align=left] [/align]
[align=left]/* MD5 block update operation. Continues an MD5 message-digest[/align]
[align=left]operation, processing another message block, and updating the[/align]
[align=left]context.[/align]
[align=left]*/[/align]
[align=left]void MD5_CTX::MD5Update (unsignedchar *input,unsignedint inputLen)[/align]
[align=left]{[/align]
[align=left]unsignedint i, index, partLen;[/align]
[align=left][/align]
[align=left]/* Compute number of bytes mod 64 */[/align]
[align=left] index = (unsignedint)((this->count[0] >> 3) & 0x3F);[/align]
[align=left][/align]
[align=left]/* Update number of bits */[/align]
[align=left]if ((this->count[0] += ((unsignedlongint)inputLen << 3))[/align]
[align=left] < ((unsignedlongint)inputLen << 3))[/align]
[align=left]this->count[1]++;[/align]
[align=left]this->count[1] += ((unsignedlongint)inputLen >> 29);[/align]
[align=left][/align]
[align=left] partLen = 64 - index;[/align]
[align=left][/align]
[align=left]/* Transform as many times as possible.[/align]
[align=left] */[/align]
[align=left]if (inputLen >= partLen) {[/align]
[align=left] MD5_memcpy((unsignedchar*)&this->buffer[index], [/align]
[align=left] (unsignedchar*)input, partLen);[/align]
[align=left] MD5Transform (this->state, this->buffer);[/align]
[align=left][/align]
[align=left]for (i = partLen; i + 63 < inputLen; i += 64)[/align]
[align=left] MD5Transform (this->state, &input[i]);[/align]
[align=left][/align]
[align=left] index = 0;[/align]
[align=left] }[/align]
[align=left]else[/align]
[align=left] i = 0;[/align]
[align=left][/align]
[align=left]/* Buffer remaining input */[/align]
[align=left] MD5_memcpy ((unsignedchar*)&this->buffer[index], (unsignedchar*)&input[i], inputLen-i);[/align]
[align=left]}[/align]
[align=left] [/align]
[align=left]/* MD5 finalization. Ends an MD5 message-digest operation, writing the[/align]
[align=left]the message digest and zeroizing the context.[/align]
[align=left]*/[/align]
[align=left]void MD5_CTX::MD5Final (unsignedchar digest[16])[/align]
[align=left]{[/align]
[align=left]unsignedchar bits[8];[/align]
[align=left]unsignedint index, padLen;[/align]
[align=left][/align]
[align=left]/* Save number of bits */[/align]
[align=left] Encode (bits, this->count, 8);[/align]
[align=left][/align]
[align=left]/* Pad out to 56 mod 64.[/align]
[align=left] */[/align]
[align=left] index = (unsignedint)((this->count[0] >> 3) & 0x3f);[/align]
[align=left] padLen = (index < 56) ? (56 - index) : (120 - index);[/align]
[align=left] MD5Update ( PADDING, padLen);[/align]
[align=left][/align]
[align=left]/* Append length (before padding) */[/align]
[align=left] MD5Update (bits, 8);[/align]
[align=left]/* Store state in digest */[/align]
[align=left] Encode (digest, this->state, 16);[/align]
[align=left][/align]
[align=left]/* Zeroize sensitive information.[/align]
[align=left] */[/align]
[align=left] MD5_memset ((unsignedchar*)this, 0, sizeof (*this));[/align]
[align=left]this->MD5Init();[/align]
[align=left]}[/align]
[align=left] [/align]
[align=left]/* MD5 basic transformation. Transforms state based on block.[/align]
[align=left]*/[/align]
[align=left]void MD5_CTX::MD5Transform (unsignedlongint state[4], unsignedchar block[64])[/align]
[align=left]{[/align]
[align=left]unsignedlongint a = state[0], b = state[1], c = state[2], d = state[3], x[16];[/align]
[align=left][/align]
[align=left] Decode (x, block, 64);[/align]
[align=left][/align]
[align=left]/* Round 1 */[/align]
[align=left] FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */[/align]
[align=left] FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */[/align]
[align=left] FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */[/align]
[align=left] FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */[/align]
[align=left] FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */[/align]
[align=left] FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */[/align]
[align=left] FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */[/align]
[align=left] FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */[/align]
[align=left] FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */[/align]
[align=left] FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */[/align]
[align=left] FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */[/align]
[align=left] FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */[/align]
[align=left] FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */[/align]
[align=left] FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */[/align]
[align=left] FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */[/align]
[align=left] FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */[/align]
[align=left][/align]
[align=left]/* Round 2 */[/align]
[align=left] GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */[/align]
[align=left] GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */[/align]
[align=left] GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */[/align]
[align=left] GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */[/align]
[align=left] GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */[/align]
[align=left] GG (d, a, b, c, x[10], S22, 0x2441453); /* 22 */[/align]
[align=left] GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */[/align]
[align=left] GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */[/align]
[align=left] GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */[/align]
[align=left] GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */[/align]
[align=left] GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */[/align]
[align=left] GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */[/align]
[align=left] GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */[/align]
[align=left] GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */[/align]
[align=left] GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */[/align]
[align=left] GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */[/align]
[align=left][/align]
[align=left]/* Round 3 */[/align]
[align=left] HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */[/align]
[align=left] HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */[/align]
[align=left] HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */[/align]
[align=left] HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */[/align]
[align=left] HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */[/align]
[align=left] HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */[/align]
[align=left] HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */[/align]
[align=left] HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */[/align]
[align=left] HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */[/align]
[align=left] HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */[/align]
[align=left] HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */[/align]
[align=left] HH (b, c, d, a, x[ 6], S34, 0x4881d05); /* 44 */[/align]
[align=left] HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */[/align]
[align=left] HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */[/align]
[align=left] HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */[/align]
[align=left] HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */[/align]
[align=left][/align]
[align=left]/* Round 4 */[/align]
[align=left] II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */[/align]
[align=left] II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */[/align]
[align=left] II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */[/align]
[align=left] II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */[/align]
[align=left] II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */[/align]
[align=left] II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */[/align]
[align=left] II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */[/align]
[align=left] II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */[/align]
[align=left] II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */[/align]
[align=left] II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */[/align]
[align=left] II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */[/align]
[align=left] II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */[/align]
[align=left] II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */[/align]
[align=left] II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */[/align]
[align=left] II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */[/align]
[align=left] II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */[/align]
[align=left][/align]
[align=left] state[0] += a;[/align]
[align=left] state[1] += b;[/align]
[align=left] state[2] += c;[/align]
[align=left] state[3] += d;[/align]
[align=left][/align]
[align=left]/* Zeroize sensitive information.[/align]
[align=left] */[/align]
[align=left] MD5_memset ((unsignedchar*)x, 0, sizeof (x));[/align]
[align=left]}[/align]
[align=left] [/align]
[align=left]/* Encodes input (unsigned long int) into output (unsigned char). Assumes len is[/align]
[align=left]a multiple of 4.[/align]
[align=left]*/[/align]
[align=left]void MD5_CTX::Encode (unsignedchar *output, unsignedlongint *input,unsignedint len)[/align]
[align=left]{[/align]
[align=left]unsignedint i, j;[/align]
[align=left][/align]
[align=left]for (i = 0, j = 0; j < len; i++, j += 4) {[/align]
[align=left] output[j] = (unsignedchar)(input[i] & 0xff);[/align]
[align=left] output[j+1] = (unsignedchar)((input[i] >> 8) & 0xff);[/align]
[align=left] output[j+2] = (unsignedchar)((input[i] >> 16) & 0xff);[/align]
[align=left] output[j+3] = (unsignedchar)((input[i] >> 24) & 0xff);[/align]
[align=left] }[/align]
[align=left]}[/align]
[align=left] [/align]
[align=left]/* Decodes input (unsigned char) into output (unsigned long int). Assumes len is[/align]
[align=left]a multiple of 4.[/align]
[align=left]*/[/align]
[align=left]void MD5_CTX::Decode (unsignedlongint *output, unsignedchar *input, unsignedint len)[/align]
[align=left]{[/align]
[align=left]unsignedint i, j;[/align]
[align=left][/align]
[align=left]for (i = 0, j = 0; j < len; i++, j += 4)[/align]
[align=left] output[i] = ((unsignedlongint)input[j]) | (((unsignedlongint)input[j+1]) << 8) |[/align]
[align=left] (((unsignedlongint)input[j+2]) << 16) | (((unsignedlongint)input[j+3]) << 24);[/align]
[align=left]}[/align]
[align=left] [/align]
[align=left]/* Note: Replace "for loop" with standard memcpy if possible.[/align]
[align=left]*/[/align]
[align=left] [/align]
[align=left]void MD5_CTX::MD5_memcpy (unsignedchar* output, unsignedchar* input,unsignedint len)[/align]
[align=left]{[/align]
[align=left]unsignedint i;[/align]
[align=left][/align]
[align=left]for (i = 0; i < len; i++)[/align]
[align=left] output[i] = input[i];[/align]
[align=left]}[/align]
[align=left] [/align]
[align=left]/* Note: Replace "for loop" with standard memset if possible.[/align]
[align=left]*/[/align]
[align=left]void MD5_CTX::MD5_memset (unsignedchar* output,int value,unsignedint len)[/align]
[align=left]{[/align]
[align=left]unsignedint i;[/align]
[align=left][/align]
[align=left]for (i = 0; i < len; i++)[/align]
[align=left] ((char *)output)[i] = (char)value;[/align]
[align=left]}[/align]
[align=left] [/align]