MD5算法的Qt实现

/* Reference : 1. http://zh.wikipedia.org/zh/MD5 2. http://www.cppblog.com/ant/archive/2007/09/11/31886.html State : Rewrite by Tande, 2012-08-08. */ #include <QDebug> #include <math.h> #include "md5.h" /* Operate define */ #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)))) /* r specifies the per-round shift amounts */ const int MD5::r[64] = { 7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, 5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20, 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21 }; //const uint32 MD5::k[64] = { // 0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee, // 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501, // 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be, // 0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821, // 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa, // 0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8, // 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed, // 0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a, // 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c, // 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70, // 0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05, // 0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665, // 0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039, // 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1, // 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1, // 0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391 //}; uint32 MD5::k[64] = {0}; const byte MD5::PADDING[64] = { 0x80 }; const char MD5::HEX[16] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' }; MD5::MD5() { reset(); } //MD5::MD5(const MD5 &) //{ //} //MD5& MD5::operator=(const MD5&) //{ //} MD5::MD5(const QString &str) { reset(); update(str); } MD5::MD5(const void *input, size_t length) { reset(); update(input, length); } MD5::MD5(ifstream &in) { reset(); update(in); } void MD5::reset() { _finished = false; /*Initial Key*/ //Use binary integer part of the sines of integers as constants: /* for i from 0 to 63 k[i] := floor(abs(sin(i + 1)) ¡Á 2^32) */ for(int i=0; i<64; i++) k[i] = floor(fabs(sin(i+1))*pow(2,32)); /* reset number of bits. */ _count[0] = _count[1] = 0; /* Load magic initialization constants. */ /* //Initialize variables: var int _state[0] := 0x67452301 var int _state[1] := 0xEFCDAB89 var int _state[2] := 0x98BADCFE var int _state[3] := 0x10325476 */ _state[0] = 0x67452301; _state[1] = 0xefcdab89; _state[2] = 0x98badcfe; _state[3] = 0x10325476; } const byte* MD5::digest() { if (!_finished) { _finished = true; final(); } return _digest; } void MD5::update(const void *input, size_t length) { update((const byte*)input, length); } void MD5::update(const QString &str) { update((const byte*)str.toLatin1().data(), str.length()); } void MD5::update(ifstream &in) { if (!in) { return; } std::streamsize length; char buffer[BUFFER_SIZE]; while (!in.eof()) { in.read(buffer, BUFFER_SIZE); length = in.gcount(); if (length > 0) { update(buffer, length); } } in.close(); } /* MD5 block update operation. Continues an MD5 message-digest operation, processing another message block, and updating the context. */ void MD5::update(const byte *input, size_t length) { uint32 i, index, partLen; _finished = false; /* Compute number of bytes mod 64 */ index = (uint32)((_count[0] >> 3) & 0x3f);//0x3f = 63 /* update number of bits */ if ((_count[0] += ((uint32)length << 3)) < ((uint32)length << 3)) { ++_count[1]; } _count[1] += ((uint32)length >> 29); //qDebug()<<_count[0]<<_count[1]; partLen = 64 - index; /* transform as many times as possible. */ if (length >= partLen) { memcpy(&_buffer[index], input, partLen); transform(_buffer); for (i = partLen; i + 63 < length; i += 64) { transform(&input[i]); } index = 0; } else { i = 0; } /* Buffer remaining input */ memcpy(&_buffer[index], &input[i], length - i); } /* MD5 finalization. Ends an MD5 message-_digest operation, writing the the message _digest and zeroizing the context. */ void MD5::final() { byte bits[8]; uint32 oldState[4]; uint32 oldCount[2]; uint32 index, padLen; /* Save current state and count. */ memcpy(oldState, _state, 16); memcpy(oldCount, _count, 8); /* Save number of bits */ encode(_count, bits, 8); /* Pad out to 56 mod 64. */ index = (uint32)((_count[0] >> 3) & 0x3f); padLen = (index < 56) ? (56 - index) : (120 - index); update(PADDING, padLen); /* Append length (before padding) */ update(bits, 8); /* Store state in digest */ encode(_state, _digest, 16); /* Restore current state and count. */ memcpy(_state, oldState, 16); memcpy(_count, oldCount, 8); } void MD5::transform(const byte block[64]) { /* //Initialize hash value for this chunk: var int a := _state[0] var int b := _state[1] var int c := _state[2] var int d := _state[3] */ uint32 a = _state[0], b = _state[1], c = _state[2], d = _state[3]; uint32 temp; uint32 w[16]; uint32 f; int i; int g; /* break chunk into sixteen 32-bit little-endian words w[i], 0 ¡Ü i ¡Ü 64 */ decode(block, w, 64); /* //Main loop: for i from 0 to 63 if 0 ¡Ü i ¡Ü 15 then f := (b and c) or ((not b) and d) g := i else if 16 ¡Ü i ¡Ü 31 f := (d and b) or ((not d) and c) g := (5¡Ái + 1) mod 16 else if 32 ¡Ü i ¡Ü 47 f := b xor c xor d g := (3¡Ái + 5) mod 16 else if 48 ¡Ü i ¡Ü 63 f := c xor (b or (not d)) g := (7¡Ái) mod 16 temp := d d := c c := b b := leftrotate((a + f + k[i] + w[g]),r[i]) + b a := temp Next i */ for(i=0; i<64; i++) { if(i>=0 && i<16) { f = F(b, c, d); g = i; } else if(i>=16 && i<32) { f = G(b, c, d); g = (5*i + 1)%16; } else if(i>=32 && i<48) { f = H(b, c, d); g = (3*i + 5)%16; } else if(i>=48 && i<64) { f = I(b, c, d); g = (7*i)%16; } temp = d; d = c; c = b; b = ROTATE_LEFT((a + f + k[i] + w[g]), r[i]) + b; a = temp; } /* //Add this chunk's hash to result so far: _state[0] := _state[0] + a _state[1] := _state[1] + b _state[2] := _state[2] + c _state[3] := _state[3] + d */ _state[0] += a; _state[1] += b; _state[2] += c; _state[3] += d; } /* Encodes input (ulong) into output (byte). Assumes length is a multiple of 4. */ void MD5::encode(const uint32 *input, byte *output, size_t length) { for (size_t i = 0, j = 0; j < length; ++i, j