找来了一个md5类，居然不会用？
源码：
#ifndef _4A83ED61477FA930_F472C929D56B1227_44A6_A2AA_B2EC_C401_
#define _4A83ED61477FA930_F472C929D56B1227_44A6_A2AA_B2EC_C401_
#include <memory.h>
#include <string>
struct MD5Context
{
unsigned long state[4];
unsigned long count[2];
unsigned char buffer[64];
};
class MD5 : public MD5Context
{
public:
MD5()
{
count[0] = count[1] = 0;
state[0] = 0x67452301;
state[1] = 0xefcdab89;
state[2] = 0x98badcfe;
state[3] = 0x10325476;
}
void update( const unsigned char* input, size_t inputLen )
{
unsigned int i, index, partLen;
index = (unsigned int)( ( count[0] >> 3 ) & 0x3F );
if( ( count[0] += ( (unsigned long)inputLen << 3 ) ) < ( (unsigned long)inputLen << 3 ) )
++count[1];
count[1] += ( (unsigned long)inputLen >> 29 );
partLen = 64 - index;
if( inputLen >= partLen )
{
memcpy( &buffer[index], input, partLen );
transform( state, buffer );
for( i = partLen; i + 63 < inputLen; i += 64 )
transform( state, &input[i] );
index = 0;
}
else
i = 0;
memcpy( &buffer[index], &input[i], inputLen - i );
}
unsigned char* get() const
{
MD5 m( *this );
memcpy( digest, m.pget(), sizeof( digest ) );
return digest;
}
std::string asString() const
{
unsigned char* hash = get();
std::string result;
for( int i = 0; i < 16; ++i )
{
result += ( hash[i] / 16 ) < 10 ? '0' + ( hash[i] / 16 ) : 'A' + ( hash[i] / 16 ) - 10;
result += ( hash[i] % 16 ) < 10 ? '0' + ( hash[i] % 16 ) : 'A' + ( hash[i] % 16 ) - 10;
}
return result;
}
private:
mutable unsigned char digest[16];
unsigned char* pget()
{
unsigned char bits[8];
unsigned int index, padLen;
encode( bits, count, 8 );
index = (unsigned int)( ( count[0] >> 3 ) & 0x3f );
padLen = ( index < 56 ) ? ( 56 - index ) : ( 120 - index );
static unsigned char PADDING[64] = { 0x80 };
update( PADDING, padLen );
update( bits, 8 );
encode( digest, state, 16 );
memset( (MD5Context*)this, 0, sizeof( MD5Context ) );
return digest;
}
static unsigned long F( unsigned long x, unsigned long y, unsigned long z )
{
return ( x & y ) | ( ~x & z );
}
问题点数：0、回复次数：10Top
1 楼lemony8734（lemony）回复于 2005-06-03 01:24:01 得分 0
static unsigned long G( unsigned long x, unsigned long y, unsigned long z )
{
return ( x & z) | ( y & ~z );
}
static unsigned long H( unsigned long x, unsigned long y, unsigned long z)
{
return x ^ y ^ z;
}
static unsigned long I( unsigned long x, unsigned long y, unsigned long z)
{
return y ^ ( x | ~z );
}
static unsigned long ROTATE_LEFT( unsigned long x, unsigned long n )
{
return ( x << n ) | ( x >> ( 32 - n ) );
}
static void FF( unsigned long& a, unsigned long b, unsigned long c, unsigned long d, unsigned long x, unsigned long s, unsigned long ac )
{
a += F( b , c , d ) + x + (unsigned long)ac;
a = ROTATE_LEFT( a, s );
a += b;
}
static void GG( unsigned long& a, unsigned long b, unsigned long c, unsigned long d, unsigned long x, unsigned long s, unsigned long ac )
{
a += G( b , c , d ) + x + (unsigned long)ac;
a = ROTATE_LEFT( a, s );
a += b;
}
static void HH( unsigned long& a, unsigned long b, unsigned long c, unsigned long d, unsigned long x, unsigned long s, unsigned long ac )
{
a += H( b , c , d ) + x + (unsigned long)ac;
a = ROTATE_LEFT( a, s );
a += b;
}
static void II( unsigned long& a, unsigned long b, unsigned long c, unsigned long d, unsigned long x, unsigned long s, unsigned long ac )
{
a += I( b , c , d ) + x + (unsigned long)ac;
a = ROTATE_LEFT( a, s );
a += b;
}
static void transform( unsigned long state[4], const unsigned char block[64] )
{
unsigned long 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], 7, 0xd76aa478 ); /* 1 */
FF( d, a, b, c, x[1], 12, 0xe8c7b756 ); /* 2 */
FF( c, d, a, b, x[2], 17, 0x242070db ); /* 3 */
FF( b, c, d, a, x[3], 22, 0xc1bdceee ); /* 4 */
FF( a, b, c, d, x[4], 7, 0xf57c0faf ); /* 5 */
FF( d, a, b, c, x[5], 12, 0x4787c62a ); /* 6 */
FF( c, d, a, b, x[6], 17, 0xa8304613 ); /* 7 */
FF( b, c, d, a, x[7], 22, 0xfd469501 ); /* 8 */
FF( a, b, c, d, x[8], 7, 0x698098d8 ); /* 9 */
FF( d, a, b, c, x[9], 12, 0x8b44f7af ); /* 10 */
FF( c, d, a, b, x[10], 17, 0xffff5bb1 ); /* 11 */
FF( b, c, d, a, x[11], 22, 0x895cd7be ); /* 12 */
FF( a, b, c, d, x[12], 7, 0x6b901122 ); /* 13 */
FF( d, a, b, c, x[13], 12, 0xfd987193 ); /* 14 */
FF( c, d, a, b, x[14], 17, 0xa679438e ); /* 15 */
FF( b, c, d, a, x[15], 22, 0x49b40821 ); /* 16 */
/* Round 2 */
GG( a, b, c, d, x[1], 5, 0xf61e2562 ); /* 17 */
GG( d, a, b, c, x[6], 9, 0xc040b340 ); /* 18 */
GG( c, d, a, b, x[11], 14, 0x265e5a51 ); /* 19 */
GG( b, c, d, a, x[0], 20, 0xe9b6c7aa ); /* 20 */
GG( a, b, c, d, x[5], 5, 0xd62f105d ); /* 21 */
GG( d, a, b, c, x[10], 9, 0x2441453 ); /* 22 */
GG( c, d, a, b, x[15], 14, 0xd8a1e681 ); /* 23 */
GG( b, c, d, a, x[4], 20, 0xe7d3fbc8 ); /* 24 */
GG( a, b, c, d, x[9], 5, 0x21e1cde6 ); /* 25 */
GG( d, a, b, c, x[14], 9, 0xc33707d6 ); /* 26 */
GG( c, d, a, b, x[3], 14, 0xf4d50d87 ); /* 27 */
GG( b, c, d, a, x[8], 20, 0x455a14ed ); /* 28 */
GG( a, b, c, d, x[13], 5, 0xa9e3e905 ); /* 29 */
GG( d, a, b, c, x[2], 9, 0xfcefa3f8 ); /* 30 */
GG( c, d, a, b, x[7], 14, 0x676f02d9 ); /* 31 */
GG( b, c, d, a, x[12], 20, 0x8d2a4c8a ); /* 32 */
/* Round 3 */
HH( a, b, c, d, x[5], 4, 0xfffa3942 ); /* 33 */
HH( d, a, b, c, x[8], 11, 0x8771f681 ); /* 34 */
HH( c, d, a, b, x[11], 16, 0x6d9d6122 ); /* 35 */
HH( b, c, d, a, x[14], 23, 0xfde5380c ); /* 36 */
HH( a, b, c, d, x[1], 4, 0xa4beea44 ); /* 37 */
HH( d, a, b, c, x[4], 11, 0x4bdecfa9 ); /* 38 */
HH( c, d, a, b, x[7], 16, 0xf6bb4b60 ); /* 39 */
HH( b, c, d, a, x[10], 23, 0xbebfbc70 ); /* 40 */
HH( a, b, c, d, x[13], 4, 0x289b7ec6 ); /* 41 */
HH( d, a, b, c, x[0], 11, 0xeaa127fa ); /* 42 */
HH( c, d, a, b, x[3], 16, 0xd4ef3085 ); /* 43 */
HH( b, c, d, a, x[6], 23, 0x4881d05 ); /* 44 */
HH( a, b, c, d, x[9], 4, 0xd9d4d039 ); /* 45 */
HH( d, a, b, c, x[12], 11, 0xe6db99e5 ); /* 46 */
HH( c, d, a, b, x[15], 16, 0x1fa27cf8 ); /* 47 */
HH( b, c, d, a, x[2], 23, 0xc4ac5665 ); /* 48 */
/* Round 4 */
II( a, b, c, d, x[0], 6, 0xf4292244 ); /* 49 */
II( d, a, b, c, x[7], 10, 0x432aff97 ); /* 50 */
II( c, d, a, b, x[14], 15, 0xab9423a7 ); /* 51 */
II( b, c, d, a, x[5], 21, 0xfc93a039 ); /* 52 */
II( a, b, c, d, x[12], 6, 0x655b59c3 ); /* 53 */
II( d, a, b, c, x[3], 10, 0x8f0ccc92 ); /* 54 */
II( c, d, a, b, x[10], 15, 0xffeff47d ); /* 55 */
II( b, c, d, a, x[1], 21, 0x85845dd1 ); /* 56 */
II( a, b, c, d, x[8], 6, 0x6fa87e4f ); /* 57 */
II( d, a, b, c, x[15], 10, 0xfe2ce6e0 ); /* 58 */
II( c, d, a, b, x[6], 15, 0xa3014314 ); /* 59 */
II( b, c, d, a, x[13], 21, 0x4e0811a1 ); /* 60 */
II( a, b, c, d, x[4], 6, 0xf7537e82 ); /* 61 */
II( d, a, b, c, x[11], 10, 0xbd3af235 ); /* 62 */
II( c, d, a, b, x[2], 15, 0x2ad7d2bb ); /* 63 */
II( b, c, d, a, x[9], 21, 0xeb86d391 ); /* 64 */
state[0] += a;
state[1] += b;
state[2] += c;
state[3] += d;
memset( x, 0, sizeof( x ) );
}
static void encode( unsigned char* output, const unsigned long *input, size_t len )
{
for( unsigned int 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 decode( unsigned long* output, const unsigned char* input, size_t len )
{
for( unsigned int i = 0, j = 0; j < len; ++i, j += 4 )
output[i] = input[j] | ( input[j+1] << 8) |
( input[j+2] << 16 ) | ( input[j+3] << 24 );
}
};
#endif
有没有人可以告诉我，如何在程序中去调用啊～～～～
试了好久都没有成功～～～～～～Top
2 楼Beover1984（摇滚人生）回复于 2005-06-03 09:03:33 得分 0
MD5 md5_digest;
md5.update( (unsigned char*)"abcd", 4 ); //如果数据比较大,调用多次update
cout << md5.get() << endl;Top
3 楼lemony8734（lemony）回复于 2005-06-03 16:39:28 得分 0
输出来的是乱码啊～Top
4 楼lemony8734（lemony）回复于 2005-06-03 20:13:48 得分 0
我顶～Top
5 楼boxban（冻酸梨）回复于 2005-06-03 22:33:00 得分 0
MD5 md5_digest;
md5.update( (unsigned char*)"abcd", 4 ); //如果数据比较大,调用多次update
cout << md5.asString()<< endl;
Top
6 楼lemony8734（lemony）回复于 2005-06-04 00:07:56 得分 0
我如何得到16位的密文？Top
7 楼lemony8734（lemony）回复于 2005-06-04 04:28:39 得分 0
这段代码测试成功，但是我如果对密文进行二次加密，也就是说用第一次得到的密码在加一次密Top
8 楼Beover1984（摇滚人生）回复于 2005-06-06 08:45:39 得分 0
MD5只是产生摘要不是一种加密,因为它无法逆运算Top
9 楼sizheng0320（四正）回复于 2005-06-30 10:43:18 得分 0
收藏先
在网上找到改进这个算法的，用了CString，不过我也没弄会。Top
10 楼sizheng0320（四正）回复于 2005-07-03 12:03:16 得分 0
那个asString() 是做什么的呢？我用它输出不了什么，而用get可以输出结果。
另外，“//如果数据比较大,调用多次update”是什么意思？最大能多大？Top
