Program and principle of ASP verification code

Program | Verification Code ##### Copyright reprint please reserve thank you for your cooperation
##### part of the program is taken from the network
##### Author: Yang Zi
##### email:yangzinet@hotmail.com
##### qq:21112856
##### WebSite:www.tingfo.net


Altogether 4 pages: form.asp; chk.asp; num.asp; Count.asp
Get a random number. Encryption!
into XBM image after decryption
Using session to judge

Form.asp


<%
' ### to Encrypt/decrypt include-code in your page
' ### strmyencryptedstring = encryptstring (strstring)
' ### strmydecryptedstring = decryptstring (strmyencryptedstring)
' ### you are the free to use this code as long as credits remain into place
' ### also if you are improve this code let me know.

Private Function encryptstring (strstring)
'####################################################################
' ### Crypt Function (C) 2001 by Slavic Kozyuk grindkore@yahoo.com
' ### arguments:strstring <---String wish to encrypt ###
' ### output:encrypted HEX string ###
'####################################################################

Dim Charhexset, Intstringlen, strtemp, Strraw, I, Intkey, Intoffset
Randomize Timer

Intkey = Round ((RND * 1000000) + 1000000) ' ##### Key bitsize
Intoffset = Round ((RND * 1000000) + 1000000) ' ##### keyoffset bitsize

If IsNull (strstring) = False Then
Strraw = strstring
Intstringlen = Len (Strraw)

For i = 0 to IntStringLen-1
strtemp = Left (Strraw, 1)
Strraw = Right (Strraw, Len (Strraw)-1)
Charhexset = Charhexset & Hex (ASC (strtemp) * Intkey) & Hex (Intkey)
Next

encryptstring = charhexset & "|" & Hex (Intoffset + intkey) & "|" & Hex (Intoffset)
Else
EncryptString = ""
End If
End Function




Private Function decryptstring (strcryptstring)
'####################################################################
' ### Crypt Function (C) 2001 by Slavic Kozyuk grindkore@yahoo.com
' ### arguments:encrypted HEX stringt ###
' ### output:decrypted ASCII string ###
'####################################################################
' ### Note This function uses Hexconv () and Get_hxno () functions ###
' ### so make sure they are not removed ###
'####################################################################

Dim Strraw, Arhexcharset, I, Intkey, Intoffset, Strrawkey, Strhexcrypdata


Strrawkey = Right (strcryptstring, Len (strcryptstring)-InStr (strcryptstring, "|"))
Intoffset = Right (Strrawkey, Len (Strrawkey)-InStr (Strrawkey, "|"))
Intkey = Hexconv (left (Strrawkey, InStr (Strrawkey, "|")-1))-Hexconv (Intoffset)
Strhexcrypdata = Left (strcryptstring, Len (strcryptstring)-(Len (Strrawkey) + 1))


Arhexcharset = Split (Strhexcrypdata, Hex (Intkey))

For i=0 to UBound (Arhexcharset)
Strraw = Strraw & Chr (Hexconv (Arhexcharset (i))/intkey)
Next

decryptstring = Strraw
End Function



Private Function Hexconv (Hexvar)
Dim hxx, Hxx_var, multiply
IF hexvar <> "" THEN
Hexvar = UCASE (Hexvar)
Hexvar = StrReverse (Hexvar)
DIM HX ()
REDIM HX (LEN (Hexvar))
hXX = 0
Hxx_var = 0
For hxx = 1 to LEN (Hexvar)
IF multiply = "" THEN multiply = 1
HX (HXX) = Mid (hexvar,hxx,1)
Hxx_var = (Get_hxno (HX (HXX)) * multiply) + Hxx_var
Multiply = (Multiply * 16)
NEXT
Hexvar = Hxx_var
Hexconv = Hexvar
End IF
End Function

Private Function get_hxno (GHX)
If ghx = "A" Then
GHX = 10
ElseIf ghx = "B" Then
GHX = 11
ElseIf ghx = "C" Then
GHX = 12
ElseIf ghx = "D" Then
GHX = 13
ElseIf ghx = "E" Then
GHX = 14
ElseIf ghx = "F" Then
GHX = 15
End If
Get_hxno = Ghx
End Function


%>


<%
Randomize
Value of num = Int (7999*rnd+2000) ' counter
num2 = encryptstring (num)
Session ("PWDT") =num
%>
<form action= "chk.asp" method=post>
Please enter the code: <input type= "text" name= "PWDs" >
<input type=submit value= submit >
</form>


Chk.asp
<%
If Trim (Request.Form ("PWDs")) <>trim (Session ("PWDT")) Then
%>
Input error: should be: <%=session ("PWDT")%>, but you enter: <%=request.form ("PWDs")%>
<%
Else
%>
Enter the correct
<%end if%>

Count.asp

<!--#include file= "num.asp"-->

<%
' ### to Encrypt/decrypt include-code in your page
' ### strmyencryptedstring = encryptstring (strstring)
' ### strmydecryptedstring = decryptstring (strmyencryptedstring)
' ### you are the free to use this code as long as credits remain into place
' ### also if you are improve this code let me know.

Private Function encryptstring (strstring)
'####################################################################
' ### Crypt Function (C) 2001 by Slavic Kozyuk grindkore@yahoo.com
' ### arguments:strstring <---String wish to encrypt ###
' ### output:encrypted HEX string ###
'####################################################################

Dim Charhexset, Intstringlen, strtemp, Strraw, I, Intkey, Intoffset
Randomize Timer

Intkey = Round ((RND * 1000000) + 1000000) ' ##### Key bitsize
Intoffset = Round ((RND * 1000000) + 1000000) ' ##### keyoffset bitsize

If IsNull (strstring) = False Then
Strraw = strstring
Intstringlen = Len (Strraw)

For i = 0 to IntStringLen-1
strtemp = Left (Strraw, 1)
Strraw = Right (Strraw, Len (Strraw)-1)
Charhexset = Charhexset & Hex (ASC (strtemp) * Intkey) & Hex (Intkey)
Next

encryptstring = charhexset & "|" & Hex (Intoffset + intkey) & "|" & Hex (Intoffset)
Else
EncryptString = ""
End If
End Function




Private Function decryptstring (strcryptstring)
'####################################################################
' ### Crypt Function (C) 2001 by Slavic Kozyuk grindkore@yahoo.com
' ### arguments:encrypted HEX stringt ###
' ### output:decrypted ASCII string ###
'####################################################################
' ### Note This function uses Hexconv () and Get_hxno () functions ###
' ### so make sure they are not removed ###
'####################################################################

Dim Strraw, Arhexcharset, I, Intkey, Intoffset, Strrawkey, Strhexcrypdata


Strrawkey = Right (strcryptstring, Len (strcryptstring)-InStr (strcryptstring, "|"))
Intoffset = Right (Strrawkey, Len (Strrawkey)-InStr (Strrawkey, "|"))
Intkey = Hexconv (left (Strrawkey, InStr (Strrawkey, "|")-1))-Hexconv (Intoffset)
Strhexcrypdata = Left (strcryptstring, Len (strcryptstring)-(Len (Strrawkey) + 1))


Arhexcharset = Split (Strhexcrypdata, Hex (Intkey))

For i=0 to UBound (Arhexcharset)
Strraw = Strraw & Chr (Hexconv (Arhexcharset (i))/intkey)
Next

decryptstring = Strraw
End Function



Private Function Hexconv (Hexvar)
Dim hxx, Hxx_var, multiply
IF hexvar <> "" THEN
Hexvar = UCASE (Hexvar)
Hexvar = StrReverse (Hexvar)
DIM HX ()
REDIM HX (LEN (Hexvar))
hXX = 0
Hxx_var = 0
For hxx = 1 to LEN (Hexvar)
IF multiply = "" THEN multiply = 1
HX (HXX) = Mid (hexvar,hxx,1)
Hxx_var = (Get_hxno (HX (HXX)) * multiply) + Hxx_var
Multiply = (Multiply * 16)
NEXT
Hexvar = Hxx_var
Hexconv = Hexvar
End IF
End Function

Private Function get_hxno (GHX)
If ghx = "A" Then
GHX = 10
ElseIf ghx = "B" Then
GHX = 11
ElseIf ghx = "C" Then
GHX = 12
ElseIf ghx = "D" Then
GHX = 13
ElseIf ghx = "E" Then
GHX = 14
ElseIf ghx = "F" Then
GHX = 15
End If
Get_hxno = Ghx
End Function


%>


<%
Dim Image
Dim Width, Height
Dim num
Dim digtal
Dim Length
Dim sort
Length = 4 ' Custom counter Lengths

Redim Sort (Length)

Num=cint (decryptstring) (Request.QueryString ("Sksid"))
Digital = ""
For I = 1 to Length-len (num) ' supplement 0
Digital = digital & "0"
Next
For I = 1 to Len (num)
Digital = digital & Mid (num, I, 1)
Next
For I = 1 to Len (digital)
Sort (i) = Mid (Digital, I, 1)
Next
width = 8 * Len (digital) ' breadth of the image
Height = 10 ' Elevation of image, in this case a fixed value


Response.contenttype= "Image/x-xbitmap"

HC=CHR (+) & Chr (10)

Image = "#define Counter_width" & Width & HC
Image = Image & "#define Counter_height" & Height & HC
Image = image & "Static unsigned char counter_bits[]={" & HC

For I = 1 to Height
For J = 1 to Length
Image = Image & A (sort (J), I) & ","
Next
Next

Image = Left (image, Len (image)-1) ' Remove the last comma
Image = Image & "};" & HC
%>
<%
Response.Write Image

%>

Num.asp

<%
Dim A (10,10)

A (0,1) = "0x3c" ' number 0
A (0,2) = "0x66"
A (0,3) = "0xc3"
A (0,4) = "0xc3"
A (0,5) = "0xc3"
A (0,6) = "0xc3"
A (0,7) = "0xc3"
A (0,8) = "0xc3"
A (0,9) = "0x66"
A (0,10) = "0x3c"

A (1,1) = "0x18" ' number 1
A (1,2) = "0x1c"
A (1,3) = "0x18"
A (1,4) = "0x18"
A (1,5) = "0x18"
A (1,6) = "0x18"
A (1,7) = "0x18"
A (1,8) = "0x18"
A (1,9) = "0x18"
A (0,10) = "0x7e"


A (2,1) = "0x3c" ' Number 2
A (2,2) = "0x66"
A (2,3) = "0x60"
A (2,4) = "0x60"
A (2,5) = "0x30"
A (2,6) = "0x18"
A (2,7) = "0x0c"
A (2,8) = "0x06"
A (2,9) = "0x06"
A (2,10) = "0x7e"

A (3,1) = "0x3c" ' Number 3
A (3,2) = "0x66"
A (3,3) = "0xc0"
A (3,4) = "0x60"
A (3,5) = "0x1c"
A (3,6) = "0x60"
A (3,7) = "0xc0"
A (3,8) = "0xc0"
A (3,9) = "0x66"
A (3,10) = "0x38"

A (4,1) = "0x38" ' Number 4
A (4,2) = "0x3c"
A (4,3) = "0x36"
A (4,4) = "0x33"
A (4,5) = "0x33"
A (4,6) = "0x33"
A (4,7) = "0xFF"
A (4,8) = "0x30"
A (4,9) = "0x30"
A (4,10) = "0xFE"

A (5,1) = "0xFE" ' number 5
A (5,2) = "0xFE"
A (5,3) = "0x06"
A (5,4) = "0x06"
A (5,5) = "0x3e"
A (5,6) = "0x60"
A (5,7) = "0xc0"
A (5,8) = "0xc3"
A (5,9) = "0x66"
A (5,10) = "0x3c"

A (6,1) = "0x60" ' number 6
A (6,2) = "0x30"
A (6,3) = "0x18"
A (6,4) = "0x0c"
A (6,5) = "0x3e"
A (6,6) = "0x63"
A (6,7) = "0xc3"
A (6,8) = "0xc3"
A (6,9) = "0x66"
A (6,10) = "0x3c"

A (7,1) = "0xFF" ' Number 7
A (7,2) = "0xc0"
A (7,3) = "0x60"
A (7,4) = "0x30"
A (7,5) = "0x18"
A (7,6) = "0x18"
A (7,7) = "0x18"
A (7,8) = "0x18"
A (7,9) = "0x18"
A (7,10) = "0x18"

A (8,1) = "0x3c" ' number 8
A (8,2) = "0x66"
A (8,3) = "0xc3"
A (8,4) = "0x66"
A (8,5) = "0x3c"
A (8,6) = "0x66"
A (8,7) = "0xc3"
A (8,8) = "0xc3"
A (8,9) = "0x66"
A (8,10) = "0x3c"

A (9,1) = "0x3c" ' Number 9
A (9,2) = "0x66"
A (9,3) = "0xc3"
A (9,4) = "0xc3"
A (9,5) = "0x66"
A (9,6) = "0x3c"
A (9,7) = "0x18"
A (9,8) = "0x0c"
A (9,9) = "0x06"
A (9,10) = "0x03"

%>