Simple encrypt/decrypt functions in Classic ASP - asp-classic

Question

Are there any simple encrypt/decrypt functions in Classic ASP?
The data that needs to be encrypted and decrypted is not super sensitive. So simple functions would do.

Answer 1

4guysfromrolla.com: RC4 Encryption Using ASP & VBScript
See the attachments at the end of the page.
The page layout looks a bit broken to me, but all the info is there. I made it readable it by deleting the code block from the DOM via bowser development tools.

Answer 2

Try this:
' Encrypt and decrypt functions for classic ASP (by TFI)
'********* set a random string with random length ***********
cryptkey = "GNQ?4i0-*\CldnU+[vrF1j1PcWeJfVv4QGBurFK6}*l[H1S:oY\v#U?i,oD]f/n8oFk6NesH--^PJeCLdp+(t8SVe:ewY(wR9p-CzG<,Q/(U*.pXDiz/KvnXP`BXnkgfeycb)1A4XKAa-2G}74Z8CqZ*A0P8E[S`6RfLwW+Pc}13U}_y0bfscJ<vkA[JC;0mEEuY4Q,([U*XRR}lYTE7A(O8KiF8>W/m1D*YoAlkBK#`3A)trZsO5xv#5#MRRFkt\"
'**************************** ENCRYPT FUNCTION ******************************
'*** Note: bytes 255 and 0 are converted into the same character, in order to
'*** avoid a char 0 which would terminate the string
function encrypt(inputstr)
Dim i,x
outputstr=""
cc=0
for i=1 to len(inputstr)
x=asc(mid(inputstr,i,1))
x=x-48
if x<0 then x=x+255
x=x+asc(mid(cryptkey,cc+1,1))
if x>255 then x=x-255
outputstr=outputstr&chr(x)
cc=(cc+1) mod len(cryptkey)
next
encrypt=server.urlencode(replace(outputstr,"%","%25"))
end function
'**************************** DECRYPT FUNCTION ******************************
function decrypt(byval inputstr)
Dim i,x
inputstr=urldecode(inputstr)
outputstr=""
cc=0
for i=1 to len(inputstr)
x=asc(mid(inputstr,i,1))
x=x-asc(mid(cryptkey,cc+1,1))
if x<0 then x=x+255
x=x+48
if x>255 then x=x-255
outputstr=outputstr&chr(x)
cc=(cc+1) mod len(cryptkey)
next
decrypt=outputstr
end function
'****************************************************************************
Function URLDecode(sConvert)
Dim aSplit
Dim sOutput
Dim I
If IsNull(sConvert) Then
URLDecode = ""
Exit Function
End If
'sOutput = REPLACE(sConvert, "+", " ") ' convert all pluses to spaces
sOutput=sConvert
aSplit = Split(sOutput, "%") ' next convert %hexdigits to the character
If IsArray(aSplit) Then
sOutput = aSplit(0)
For I = 0 to UBound(aSplit) - 1
sOutput = sOutput & Chr("&H" & Left(aSplit(i + 1), 2)) & Right(aSplit(i + 1), Len(aSplit(i + 1)) - 2)
Next
End If
URLDecode = sOutput
End Function

Answer 3

I know is a bit late for BrokenLink, but for the record and others like me who were looking for the same.
I found this https://www.example-code.com/vbscript/crypt_aes_encrypt_file.asp.
It needs to install a chilkat ActiveX component on WindowsServer. But this inconvenient becomes convenient when looking resources and processing time.
Its very easy to use, and the given example is pretty clear. To make it your own, just change the "keyHex" variable value and voilá.