AES算法 asp源码
发布时间：2009-08-28 13:05:00
随着对称密码的发展,DES数据加密标准算法由于密钥长度较小(56位),已经不适应当今分布式开放网络对数据加密安全性的要求，因此1997年NIST公开征集新的数据加密标准,即AES。经过三轮的筛选,比利时Joan Daeman和Vincent Rijmen提交的Rijndael算法被提议为AES的最终算法。此算法将成为美国新的数据加密标准而被广泛应用在各个领域中。
尽管人们对AES还有不同的看法,但总体来说,AES作为新一代的数据加密标准汇聚了强安全性、高性能、高效率、易用和灵活等优点。AES设计有三个密钥长度:128,192,256位，相对而言，AES的128密钥比DES的56密钥强1021倍。AES算法主要包括三个方面：轮变化、圈数和密钥扩展。本文以128为例，介绍算法的基本原理；结合AVR汇编语言，实现高级数据加密算法AES。
AES是分组密钥，算法输入128位数据，密钥长度也是128位。用Nr表示对一个数据分组加密的轮数（加密轮数与密钥长度的关系如表1所列）。每一轮都需要一个与输入分组具有相同长度的扩展密钥Expandedkey(i)的参与。由于外部输入的加密密钥K长度有限,所以在算法中要用一个密钥扩展程序(Keyexpansion)把外部密钥K扩展成更长的比特串,以生成各轮的加密和解密密钥。
<％
Class TAES
Private cls_lOnBits(30), cls_l2Power(30), cls_bytOnBits(7),cls_byt2Power(7)
Private cls_InCo(3)
Private cls_fbsub(255), cls_rbsub(255), cls_ptab(255), cls_ltab(255), cls_ftable(255), cls_rtable(255), cls_rco(29)
Private cls_Nk, cls_Nb, cls_Nr
Private cls_fi(23), cls_ri(23), cls_fkey(119), cls_rkey(119)
Private Sub Class_Initialize()
cls_InCo(0) = &HB
cls_InCo(1) = &HD
cls_InCo(2) = &H9
cls_InCo(3) = &HE
cls_bytOnBits(0) = 1
cls_bytOnBits(1) = 3
cls_bytOnBits(2) = 7
cls_bytOnBits(3) = 15
cls_bytOnBits(4) = 31
cls_bytOnBits(5) = 63
cls_bytOnBits(6) = 127
cls_bytOnBits(7) = 255
cls_byt2Power(0) = 1
cls_byt2Power(1) = 2
cls_byt2Power(2) = 4
cls_byt2Power(3) = 8
cls_byt2Power(4) = 16
cls_byt2Power(5) = 32
cls_byt2Power(6) = 64
cls_byt2Power(7) = 128
cls_lOnBits(0) = 1
cls_lOnBits(1) = 3
cls_lOnBits(2) = 7
cls_lOnBits(3) = 15
cls_lOnBits(4) = 31
cls_lOnBits(5) = 63
cls_lOnBits(6) = 127
cls_lOnBits(7) = 255
cls_lOnBits(8) = 511
cls_lOnBits(9) = 1023
cls_lOnBits(10) = 2047
cls_lOnBits(11) = 4095
cls_lOnBits(12) = 8191
cls_lOnBits(13) = 16383
cls_lOnBits(14) = 32767
cls_lOnBits(15) = 65535
cls_lOnBits(16) = 131071
cls_lOnBits(17) = 262143
cls_lOnBits(18) = 524287
cls_lOnBits(19) = 1048575
cls_lOnBits(20) = 2097151
cls_lOnBits(21) = 4194303
cls_lOnBits(22) = 8388607
cls_lOnBits(23) = 16777215
cls_lOnBits(24) = 33554431
cls_lOnBits(25) = 67108863
cls_lOnBits(26) = 134217727
cls_lOnBits(27) = 268435455
cls_lOnBits(28) = 536870911
cls_lOnBits(29) = 1073741823
cls_lOnBits(30) = 2147483647
cls_l2Power(0) = 1
cls_l2Power(1) = 2
cls_l2Power(2) = 4
cls_l2Power(3) = 8
cls_l2Power(4) = 16
cls_l2Power(5) = 32
cls_l2Power(6) = 64
cls_l2Power(7) = 128
cls_l2Power(8) = 256
cls_l2Power(9) = 512
cls_l2Power(10) = 1024
cls_l2Power(11) = 2048
cls_l2Power(12) = 4096
cls_l2Power(13) = 8192
cls_l2Power(14) = 16384
cls_l2Power(15) = 32768
cls_l2Power(16) = 65536
cls_l2Power(17) = 131072
cls_l2Power(18) = 262144
cls_l2Power(19) = 524288
cls_l2Power(20) = 1048576
cls_l2Power(21) = 2097152
cls_l2Power(22) = 4194304
cls_l2Power(23) = 8388608
cls_l2Power(24) = 16777216
cls_l2Power(25) = 33554432
cls_l2Power(26) = 67108864
cls_l2Power(27) = 134217728
cls_l2Power(28) = 268435456
cls_l2Power(29) = 536870912
cls_l2Power(30) = 1073741824
End Sub
Private Function ByteSub(x)
Dim y, z
z = x
y = cls_ptab(255 - cls_ltab(z))
z = y
z = ROTLB(z, 1)
y = y Xor z
z = ROTLB(z, 1)
y = y Xor z
z = ROTLB(z, 1)
y = y Xor z
z = ROTLB(z, 1)
y = y Xor z
y = y Xor &H63
ByteSub = y
End Function
Private Function SHL(lValue, iShiftBits)
If iShiftBits = 0 Then
SHL = lValue
Exit Function
ElseIf iShiftBits = 31 Then
If lValue And 1 Then
SHL = &H80000000
Else
SHL = 0
End If
Exit Function
ElseIf iShiftBits < 0 Or iShiftBits > 31 Then
Err.Raise 6
End If
If (lValue And cls_l2Power(31 - iShiftBits)) Then
SHL = ((lValue And cls_lOnBits(31 - (iShiftBits + 1))) * cls_l2Power(iShiftBits)) Or &H80000000
Else
SHL = ((lValue And cls_lOnBits(31 - iShiftBits)) * cls_l2Power(iShiftBits))
End If
End Function
Private Function SHR(lValue, iShiftBits)
If iShiftBits = 0 Then
SHR = lValue
Exit Function
ElseIf iShiftBits = 31 Then
If lValue And &H80000000 Then
SHR = 1
Else
SHR = 0
End If
Exit Function
ElseIf iShiftBits < 0 Or iShiftBits > 31 Then
Err.Raise 6
End If
SHR = (lValue And &H7FFFFFFE) \ cls_l2Power(iShiftBits)
If (lValue And &H80000000) Then
SHR = (SHR Or (&H40000000 \ cls_l2Power(iShiftBits - 1)))
End If
End Function
Private Function SHLB(bytValue, bytShiftBits)
If bytShiftBits = 0 Then
SHLB = bytValue
Exit Function
ElseIf bytShiftBits = 7 Then
If bytValue And 1 Then
SHLB = &H80
Else
SHLB = 0
End If
Exit Function
ElseIf bytShiftBits < 0 Or bytShiftBits > 7 Then
Err.Raise 6
End If
SHLB = ((bytValue And cls_bytOnBits(7 - bytShiftBits)) * cls_byt2Power(bytShiftBits))
End Function
Private Function SHRB(bytValue, bytShiftBits)
If bytShiftBits = 0 Then
SHRB = bytValue
Exit Function
ElseIf bytShiftBits = 7 Then
If bytValue And &H80 Then
SHRB = 1
Else
SHRB = 0
End If
Exit Function
ElseIf bytShiftBits < 0 Or bytShiftBits > 7 Then
Err.Raise 6
End If
SHRB = bytValue \ cls_byt2Power(bytShiftBits)
End Function
Private Function ROTL(lValue, iShiftBits)
ROTL = SHL(lValue, iShiftBits) Or SHR(lValue, (32 - iShiftBits))
End Function
Private Function ROTLB(bytValue, bytShiftBits)
ROTLB = SHLB(bytValue, bytShiftBits) Or SHRB(bytValue, (8 - bytShiftBits))
End Function
Private Function Pack(b())
Dim lCount
Dim lTemp
For lCount = 0 To 3
lTemp = b(lCount)
Pack = Pack Or SHL(lTemp, (lCount * 8))
Next
End Function
Private Function PackFrom(b(), k)
Dim lCount
Dim lTemp
For lCount = 0 To 3
lTemp = b(lCount + k)
PackFrom = PackFrom Or SHL(lTemp, (lCount * 8))
Next
End Function
Private Sub Unpack(a, b())
b(0) = a And cls_lOnBits(7)
b(1) = SHR(a, 8) And cls_lOnBits(7)
b(2) = SHR(a, 16) And cls_lOnBits(7)
b(3) = SHR(a, 24) And cls_lOnBits(7)
End Sub
Private Sub UnpackFrom(a, ByRef b(), k)
b(0 + k) = a And cls_lOnBits(7)
b(1 + k) = SHR(a, 8) And cls_lOnBits(7)
b(2 + k) = SHR(a, 16) And cls_lOnBits(7)
b(3 + k) = SHR(a, 24) And cls_lOnBits(7)
End Sub
Private Function IsInitialized(ByVal a_aArray)
On Error Resume Next
IsInitialized = IsNumeric(UBound(a_aArray))
End Function
Private Sub CopyBytesASP(bytDest, lDestStart, bytSource(), lSourceStart, lLength)
Dim lCount
lCount = 0
Do
bytDest(lDestStart + lCount) = bytSource(lSourceStart + lCount)
lCount = lCount + 1
Loop Until lCount = lLength
End Sub
Private Function xtime(a)
Dim b
If (a And &H80) Then
b = &H1B
Else
b = 0
End If
xtime = SHLB(a, 1)
xtime = xtime Xor b
End Function
Private Function bmul(x, y)
If x <> 0 And y <> 0 Then
bmul = cls_ptab((CLng(cls_ltab(x)) + CLng(cls_ltab(y))) Mod 255)
Else
bmul = 0
End If
End Function
Private Function SubByte(a)
Dim b(3)
Unpack a, b
b(0) = cls_fbsub(b(0))
b(1) = cls_fbsub(b(1))
b(2) = cls_fbsub(b(2))
b(3) = cls_fbsub(b(3))
SubByte = Pack(b)
End Function
Private Function product(x, y)
Dim xb(3), yb(3)
Unpack x, xb
Unpack y, yb
product = bmul(xb(0), yb(0)) Xor bmul(xb(1), yb(1)) Xor bmul(xb(2), yb(2)) Xor bmul(xb(3), yb(3))
End Function
Private Function InvMixCol(x)
Dim y, m
Dim b(3)
m = Pack(cls_InCo)
b(3) = product(m, x)
m = ROTL(m, 24)
b(2) = product(m, x)
m = ROTL(m, 24)
b(1) = product(m, x)
m = ROTL(m, 24)
b(0) = product(m, x)
y = Pack(b)
InvMixCol = y
End Function
Public Sub gentables()
Dim i, y, ib
Dim b(3)
cls_ltab(0) = 0
cls_ltab(1) = 0
cls_ltab(3) = 1
cls_ptab(0) = 1
cls_ptab(1) = 3
For i = 2 To 255
cls_ptab(i) = cls_ptab(i - 1) Xor xtime(cls_ptab(i - 1))
cls_ltab(cls_ptab(i)) = i
Next
cls_fbsub(0) = &H63
cls_rbsub(&H63) = 0
For i = 1 To 255
ib = i
y = ByteSub(ib)
cls_fbsub(i) = y
cls_rbsub(y) = i
Next
y = 1
For i = 0 To 29
cls_rco(i) = y
y = xtime(y)
Next
For i = 0 To 255
y = cls_fbsub(i)
b(3) = y Xor xtime(y)
b(2) = y
b(1) = y
b(0) = xtime(y)
cls_ftable(i) = Pack(b)
y = cls_rbsub(i)
b(3) = bmul(cls_InCo(0), y)
b(2) = bmul(cls_InCo(1), y)
b(1) = bmul(cls_InCo(2), y)
b(0) = bmul(cls_InCo(3), y)
cls_rtable(i) = Pack(b)
Next
End Sub
Private Sub gkey(nb, nk, key())
Dim i, j, k, m, n
Dim C1, C2, C3
Dim CipherKey(7)
cls_Nb = nb
cls_Nk = nk
If cls_Nb >= cls_Nk Then
cls_Nr = 6 + cls_Nb
Else
cls_Nr = 6 + cls_Nk
End If
C1 = 1
If cls_Nb < 8 Then
C2 = 2
C3 = 3
Else
C2 = 3
C3 = 4
End If
For j = 0 To nb - 1
m = j * 3
cls_fi(m) = (j + C1) Mod nb
cls_fi(m + 1) = (j + C2) Mod nb
cls_fi(m + 2) = (j + C3) Mod nb
cls_ri(m) = (nb + j - C1) Mod nb
cls_ri(m + 1) = (nb + j - C2) Mod nb
cls_ri(m + 2) = (nb + j - C3) Mod nb
Next
N = cls_Nb * (cls_Nr + 1)
For i = 0 To cls_Nk - 1
j = i * 4
CipherKey(i) = PackFrom(key, j)
Next
For i = 0 To cls_Nk - 1
cls_fkey(i) = CipherKey(i)
Next
j = cls_Nk
k = 0
Do While j < N
cls_fkey(j) = cls_fkey(j - cls_Nk) Xor _
SubByte(ROTL(cls_fkey(j - 1), 24)) Xor cls_rco(k)
If cls_Nk <= 6 Then
i = 1
Do While i < cls_Nk And (i + j) < N
cls_fkey(i + j) = cls_fkey(i + j - cls_Nk) Xor _
cls_fkey(i + j - 1)
i = i + 1
Loop
Else
i = 1
Do While i < 4 And (i + j) < N
cls_fkey(i + j) = cls_fkey(i + j - cls_Nk) Xor _
cls_fkey(i + j - 1)
i = i + 1
Loop
If j + 4 < N Then
cls_fkey(j + 4) = cls_fkey(j + 4 - cls_Nk) Xor _
SubByte(cls_fkey(j + 3))
End If
i = 5
Do While i < cls_Nk And (i + j) < N
cls_fkey(i + j) = cls_fkey(i + j - cls_Nk) Xor _
cls_fkey(i + j - 1)
i = i + 1
Loop
End If
j = j + cls_Nk
k = k + 1
Loop
For j = 0 To cls_Nb - 1
cls_rkey(j + N - nb) = cls_fkey(j)
Next
i = cls_Nb
Do While i < N - cls_Nb
k = N - cls_Nb - i
For j = 0 To cls_Nb - 1
cls_rkey(k + j) = InvMixCol(cls_fkey(i + j))
Next
i = i + cls_Nb
Loop
j = N - cls_Nb
Do While j < N
cls_rkey(j - N + cls_Nb) = cls_fkey(j)
j = j + 1
Loop
End Sub
Private Sub EncryptData(buff())
Dim i, j, k, m, x, y, t
Dim a(7), b(7)
For i = 0 To cls_Nb - 1
j = i * 4
a(i) = PackFrom(buff, j)
a(i) = a(i) Xor cls_fkey(i)
Next
k = cls_Nb
x = a
y = b
For i = 1 To cls_Nr - 1
For j = 0 To cls_Nb - 1
m = j * 3
y(j) = cls_fkey(k) Xor cls_ftable(x(j) And cls_lOnBits(7)) Xor _
ROTL(cls_ftable(SHR(x(cls_fi(m)), 8) And cls_lOnBits(7)), 8) Xor _
ROTL(cls_ftable(SHR(x(cls_fi(m + 1)), 16) And cls_lOnBits(7)), 16) Xor _
ROTL(cls_ftable(SHR(x(cls_fi(m + 2)), 24) And cls_lOnBits(7)), 24)
k = k + 1
Next
t = x
x = y
y = t
Next
For j = 0 To cls_Nb - 1
m = j * 3
y(j) = cls_fkey(k) Xor cls_fbsub(x(j) And cls_lOnBits(7)) Xor _
ROTL(cls_fbsub(SHR(x(cls_fi(m)), 8) And cls_lOnBits(7)), 8) Xor _
ROTL(cls_fbsub(SHR(x(cls_fi(m + 1)), 16) And cls_lOnBits(7)), 16) Xor _
ROTL(cls_fbsub(SHR(x(cls_fi(m + 2)), 24) And cls_lOnBits(7)), 24)
k = k + 1
Next
For i = 0 To cls_Nb - 1
j = i * 4
UnpackFrom y(i), buff, j
x(i) = 0
y(i) = 0
Next
End Sub
Private Sub DecryptData(buff())
Dim i, j, k, m, x, y, t
Dim a(7), b(7)
For i = 0 To cls_Nb - 1
j = i * 4
a(i) = PackFrom(buff, j)
a(i) = a(i) Xor cls_rkey(i)
Next
k = cls_Nb
x = a
y = b
For i = 1 To cls_Nr - 1
For j = 0 To cls_Nb - 1
m = j * 3
y(j) = cls_rkey(k) Xor cls_rtable(x(j) And cls_lOnBits(7)) Xor _
ROTL(cls_rtable(SHR(x(cls_ri(m)), 8) And cls_lOnBits(7)), 8) Xor _
ROTL(cls_rtable(SHR(x(cls_ri(m + 1)), 16) And cls_lOnBits(7)), 16) Xor _
ROTL(cls_rtable(SHR(x(cls_ri(m + 2)), 24) And cls_lOnBits(7)), 24)
k = k + 1
Next
t = x
x = y
y = t
Next
For j = 0 To cls_Nb - 1
m = j * 3
y(j) = cls_rkey(k) Xor cls_rbsub(x(j) And cls_lOnBits(7)) Xor _
ROTL(cls_rbsub(SHR(x(cls_ri(m)), 8) And cls_lOnBits(7)), 8) Xor _
ROTL(cls_rbsub(SHR(x(cls_ri(m + 1)), 16) And cls_lOnBits(7)), 16) Xor _
ROTL(cls_rbsub(SHR(x(cls_ri(m + 2)), 24) And cls_lOnBits(7)), 24)
k = k + 1
Next
For i = 0 To cls_Nb - 1
j = i * 4
UnpackFrom y(i), buff, j
x(i) = 0
y(i) = 0
Next
End Sub
Public Function Encrypt(a_sMsg, a_sPassword)
Dim bytKey(31)
Dim bytTemp(31)
Dim bytLen(3)
Dim bytIn()
Dim bytOut()
Dim lCount, lLength, lEncodedLength, lPosition
Dim bytMessage
Dim sResult
lLength = Len(a_sMsg)
ReDim bytMessage(lLength-1)
For lCount = 1 To lLength
bytMessage(lCount-1)=CByte(AscB(Mid(a_sMsg,lCount,1)))
Next
lLength = Len(a_sPassword)
ReDim bytPassword(lLength-1)
For lCount = 1 To lLength
bytPassword(lCount-1)=CByte(AscB(Mid(a_sPassword,lCount,1)))
Next
If Not IsInitialized(bytMessage) Then
Exit Function
End If
If Not IsInitialized(bytPassword) Then
Exit Function
End If
For lCount = 0 To UBound(bytPassword)
bytKey(lCount) = bytPassword(lCount)
If lCount = 31 Then
Exit For
End If
Next
Call genTables()
Call gKey(8, 8, bytKey)
lLength = UBound(bytMessage) + 1
lEncodedLength = lLength + 4
If lEncodedLength Mod 32 <> 0 Then
lEncodedLength = lEncodedLength + 32 - (lEncodedLength Mod 32)
End If
ReDim bytIn(lEncodedLength - 1)
ReDim bytOut(lEncodedLength - 1)
Unpack lLength, bytIn
CopyBytesASP bytIn, 4, bytMessage, 0, lLength
For lCount = 0 To lEncodedLength - 1 Step 32
CopyBytesASP bytTemp, 0, bytIn, lCount, 32
EncryptData bytTemp
CopyBytesASP bytOut, lCount, bytTemp, 0, 32
Next
sResult = ""
For lCount = 0 To UBound(bytOut)
sResult = sResult & Right("0" & Hex(bytOut(lCount)), 2)
Next
Encrypt = sResult
End Function
Public Function Decrypt(a_sIn, a_sPassword)
Dim bytMessage(), bytOut()
Dim bytKey(31), bytTemp(31), bytIn, bytPassword, bytLen(3)
Dim lCount, lLength, lEncodedLength, lPosition
Dim sResult, sMsg : sMsg = Trim(a_sIn)
Dim iCount
If sMsg="" Or IsEmpty(sMsg) Or IsNull(sMsg) Then
Exit Function
End If
lLength = Len(sMsg)
ReDim bytIn(lLength/2-1)
iCount = 0
For lCount = 1 To lLength Step 2
bytIn(iCount) = CByte(Int("&H" & Mid(sMsg, lCount,2)))
iCount = iCount + 1
Next
lLength = Len(a_sPassword)
ReDim bytPassword(lLength-1)
For lCount = 1 To lLength
bytPassword(lCount-1)=CByte(AscB(Mid(a_sPassword,lCount,1)))
Next
If Not IsInitialized(bytIn) Then
Exit Function
End If
If Not IsInitialized(bytPassword) Then
Exit Function
End If
lEncodedLength = UBound(bytIn) + 1
If Int(lEncodedLength) Mod 32 <> 0 Then
Exit Function
End If
For lCount = 0 To UBound(bytPassword)
bytKey(lCount) = bytPassword(lCount)
If lCount = 31 Then
Exit For
End If
Next
Call genTables()
Call gKey(8, 8, bytKey)
ReDim bytOut(lEncodedLength - 1)
For lCount = 0 To lEncodedLength - 1 Step 32
CopyBytesASP bytTemp, 0, bytIn, lCount, 32
DecryptData bytTemp
CopyBytesASP bytOut, lCount, bytTemp, 0, 32
Next
lLength = Pack(bytOut)
If lLength > lEncodedLength - 4 Then
Exit Function
End If
ReDim bytMessage(lLength - 1)
CopyBytesASP bytMessage, 0, bytOut, 4, lLength
lLength = UBound(bytMessage)
sResult = ""
For lCount = 0 To lLength
sResult = sResult & Chr(bytMessage(lCount))
Next
Decrypt = sResult
End Function
End Class
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- JS操作二进制很麻烦，而且一直没有一个好的无损压缩工具来实现纯文本的压缩。所以钻研了一段时间的gzip，后来发现还是仅用 LZ77 比较容易
- 下面我们用HTML来上传3个文件看看，它包含了文本描述字段和多项选择:upload.htm<HTML> <BOD
- IE(internet explorer)公司:微软(MicroSoft)布局引擎:Trident(也做MSHTML)注:解析渲染
- 事务日志文件Transaction Log File是用来记录数据库更新情况的文件，扩展名为ldf。在 SQL Server 7.0 和 S
- 大家一定使用过 phpmyadmin 里面的数据库导入，导出功能，非常方便。但是在实际应用中，我发现如下几个问题：1、数据库超过一定尺寸，比
- 我设计第一篇网页的时候，就遇到了字体的设置问题。我发现如果用软件约定的字体大小，则显示效果会很难看的。我是用FrontPage2000作网页
- <script language="JScript" Runat="Server&q
- 首先，我要在这里写上一些很官方的概念，意在说明面向对象是很具体化的，很实体的模式，不能让有些人看见“对象&rdq
- win2000注册表程序 regedt32.exe下面是解决IIS出现Active Server Pages错误&
- 开发过程中，错误免不了。为了纠正错误与规范化。可以使用MS SQL Server的系统存储过程sp_rename与OBJECTPROPERT
- 一个网站能切换不同的CSS风格大家应该都了解，像众所周知的腾讯在今年改版时也增加了切换皮肤的功能。根据时间自动调整站点风格是不错的想法，这种
- 即使MyISAM表格式非常可靠(SQL语句对表做的所有改变在语句返回之前被写下)，如果下列任何事件发生，你依然可以获得损坏的表：&m
