Re: Encoding Schemes

[Vasiliy <security () gugol ru>]

Jason binger wrote:

> Hi,
>
> I am reviewing a web app and I would like to know what
> encoding scheme they are using to encode their
> parameters.
>
> 123456 encodes to B8DCCEA11586
> ABCDEF encodes to C8ACBED165F6
>
> Any help would be appreciated.
>
> Cheers.

  Seems to be quite simple. ASCII hex number of every symbol xored over 
following values according to symbol position:

position:  | 1 | 2 | 3 | 4 | 5 | 6|
xor value: |89 |EE |FD |95 |20 |B0|

  So, the first string:
      1 (31 in hex) xor 89 = B8
      2 (32 in hex) xor EE = DC
      ... etc ...

  And the second:
      A (41 in hex) xor 89 = C8
      B (42 in hex) xor EE = AC
      ... etc ...


--
wbr,
Vasiliy