Um, unless I'm mistaken, this is a pretty basic cypher - are you after
encrypting something that NEEDS to stay crypted, or just scrambling
something so a luser can't get at it? if its the latter, this should be
fine, but a cryptographer work his salt should be able to go thru this in
about 2 seconds flat. Something like MD5 or RC4 are _proven_ "secure" by
years of testing etc.
Another thing to look at could be Bill Raike's library - not sure of the
URL, but's he's over here in NZ somewhere :)
Nic.
----- Original Message -----
From: "Ross Levis" <[EMAIL PROTECTED]>
To: "Multiple recipients of list delphi" <[EMAIL PROTECTED]>
Sent: Wednesday, September 26, 2001 2:53 PM
Subject: RE: [DUG]: String Encryption routine
> Hi Phil
>
> This looks useful. Can I assume it decrypts as well by passing the
Encrypt
> param as False?
>
> Cheers,
> Ross.
>
> Phil Scadden wrote:
> > here is my favourite, very simple string to hex gobbledegooker.
> >
> > Function Encrypt (Src:String; Key:String; Encrypt : Boolean):string;
> > var
> > idx :integer;
> > KeyLen :Integer;
> > KeyPos :Integer;
> > offset :Integer;
> > dest :string;
> > SrcPos :Integer;
> > SrcAsc :Integer;
> > TmpSrcAsc :Integer;
> > Range :Integer;
> >
> > begin
> > KeyLen:=Length(Key);
> > if KeyLen = 0 then key:='235jhsf9msf;&#@*#';
> > KeyPos:=0;
> > SrcAsc:=0;
> > Range:=256;
> > if Encrypt then
> > begin
> > Randomize;
> > offset:=Random(Range);
> > dest:=format('%1.2x',[offset]);
> > for SrcPos := 1 to Length(Src) do
> > begin
> > SrcAsc:=(Ord(Src[SrcPos]) + offset) MOD 255;
> > if KeyPos < KeyLen then KeyPos:= KeyPos + 1
> > else KeyPos:=1;
> > SrcAsc:= SrcAsc xor Ord(Key[KeyPos]);
> > dest:=dest + format('%1.2x',[SrcAsc]);
> > offset:=SrcAsc;
> > end;
> > end
> > else
> > begin
> > offset:=StrToInt('$'+ copy(src,1,2));
> > SrcPos:=3;
> > repeat
> > SrcAsc:=StrToInt('$'+ copy(src,SrcPos,2));
> > if KeyPos < KeyLen Then KeyPos := KeyPos + 1
> > else KeyPos := 1;
> > TmpSrcAsc := SrcAsc xor Ord(Key[KeyPos]);
> > if TmpSrcAsc <= offset then
> > TmpSrcAsc := 255 + TmpSrcAsc - offset
> > else
> > TmpSrcAsc := TmpSrcAsc - offset;
> > dest := dest + chr(TmpSrcAsc);
> > offset:=srcAsc;
> > SrcPos:=SrcPos + 2;
> > until SrcPos >= Length(Src);
> > end;
> > Result:=Dest;
> > end;
> >
> > ----------------------------------------------------------
> > Phil Scadden, Institute of Geological and Nuclear Sciences
> > 41 Bell Rd South, PO Box 30368, Lower Hutt, New Zealand
> > Ph +64 4 5704821, fax +64 4 5704603
> >
> > --------------------------------------------------------------
> > -------------
> > New Zealand Delphi Users group - Delphi List -
> > [EMAIL PROTECTED]
> > Website: http://www.delphi.org.nz
> > To UnSub, send email to: [EMAIL PROTECTED]
> > with body of "unsubscribe delphi"
> > Web Archive at: http://www.mail-archive.com/delphi%40delphi.org.nz/
> >
> --------------------------------------------------------------------------
-
> New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED]
> Website: http://www.delphi.org.nz
> To UnSub, send email to: [EMAIL PROTECTED]
> with body of "unsubscribe delphi"
> Web Archive at: http://www.mail-archive.com/delphi%40delphi.org.nz/
>
---------------------------------------------------------------------------
New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED]
Website: http://www.delphi.org.nz
To UnSub, send email to: [EMAIL PROTECTED]
with body of "unsubscribe delphi"
Web Archive at: http://www.mail-archive.com/delphi%40delphi.org.nz/
