日期:2014-05-17  浏览次数:20395 次

.net中数据库保存的是MD5的账号和密码。取出这些值如何判断账号密码是否正确!
我是刚毕业的实习生,
在公司里保存账号和密码是用MD5加密过的。
那现在我取出来了MD5加密后的字符串,如何判断账号和密码是否正确呢。?

------解决方案--------------------
Private Function WordToHex(lValue)
Dim lByte
Dim lCount

For lCount = 0 To 3
lByte = RShift(lValue, lCount * BITS_TO_A_BYTE) And m_lOnBits(BITS_TO_A_BYTE - 1)
WordToHex = WordToHex & Right("0" & Hex(lByte), 2)
Next
End Function

Public Function calcMD5(sMessage)
Dim x
Dim k
Dim AA
Dim BB
Dim CC
Dim DD
Dim a
Dim b
Dim c
Dim d

Const S11 = 7
Const S12 = 12
Const S13 = 17
Const S14 = 22
Const S21 = 5
Const S22 = 9
Const S23 = 14
Const S24 = 20
Const S31 = 4
Const S32 = 11
Const S33 = 16
Const S34 = 23
Const S41 = 6
Const S42 = 10
Const S43 = 15
Const S44 = 21

x = ConvertToWordArray(sMessage)

a = &H67452301
b = &HEFCDAB89
c = &H98BADCFE
d = &H10325476

For k = 0 To UBound(x) Step 16
AA = a
BB = b
CC = c
DD = d

FF a, b, c, d, x(k + 0), S11, &HD76AA478
FF d, a, b, c, x(k + 1), S12, &HE8C7B756
FF c, d, a, b, x(k + 2), S13, &H242070DB
FF b, c, d, a, x(k + 3), S14, &HC1BDCEEE
FF a, b, c, d, x(k + 4), S11, &HF57C0FAF
FF d, a, b, c, x(k + 5), S12, &H4787C62A
FF c, d, a, b, x(k + 6), S13, &HA8304613
FF b, c, d, a, x(k + 7), S14, &HFD469501
FF a, b, c, d, x(k + 8), S11, &H698098D8
FF d, a, b, c, x(k + 9), S12, &H8B44F7AF
FF c, d, a, b, x(k + 10), S13, &HFFFF5BB1
FF b, c, d, a, x(k + 11), S14, &H895CD7BE
FF a, b, c, d, x(k + 12), S11, &H6B901122
FF d, a, b, c, x(k + 13), S12, &HFD987193
FF c, d, a, b, x(k + 14), S13, &HA679438E
FF b, c, d, a, x(k + 15), S14, &H49B40821

GG a, b, c, d, x(k + 1), S21, &HF61E2562
GG d, a, b, c, x(k + 6), S22, &HC040B340
GG c, d, a, b, x(k + 11), S23, &H265E5A51
GG b, c, d, a, x(k + 0), S24, &HE9B6C7AA
GG a, b, c, d, x(k + 5), S21, &HD62F105D
GG d, a, b, c, x(k + 10), S22, &H2441453
GG c, d, a, b, x(k + 15), S23, &HD8A1E681
GG b, c, d, a, x(k + 4), S24, &HE7D3FBC8
GG a, b, c, d, x(k + 9), S21, &H21E1CDE6
GG d, a, b, c, x(k + 14), S22, &HC33707D6
GG c, d, a, b, x(k + 3), S23, &HF4D50D87
GG b, c, d, a, x(k + 8), S24, &H455A14ED
GG a, b, c, d, x(k + 13), S21, &HA9E3E905
GG d, a, b, c, x(k + 2), S22, &HFCEFA3F8
GG c, d, a, b, x(k + 7), S23, &H676F02D9
GG b, c, d, a, x(k + 12), S24, &H8D2A4C8A

HH a, b, c, d, x(k + 5), S31, &HFFFA3942
HH d, a, b, c, x(k + 8), S32, &H8771F681
HH c, d, a, b, x(k + 11), S33, &H6D9D6122
HH b, c, d, a, x(k + 14), S34, &HFDE5380C
HH a, b, c, d, x(k + 1), S31, &HA4BEEA44
HH d, a, b, c, x(k + 4), S32, &H4BDECFA9
HH c, d, a, b, x(k + 7), S33, &HF6BB4B60
HH b, c, d, a, x(k + 10), S34, &HBEBFBC70
HH a, b, c, d, x(k + 13), S31, &H289B7EC6
HH d, a, b, c, x(k + 0), S32, &HEAA127FA
HH c, d, a, b, x(k + 3), S33, &HD4EF3085
HH b, c, d, a, x(k + 6), S34, &H4881D05
HH a, b, c, d, x(k + 9), S31, &HD9D4D039
HH d, a, b, c, x(k + 12)