Re: [PHP] $_GET is Mangling Base64 value

On Thu, Mar 11, 2010 at 4:57 PM, George Langley <[email protected]>wrote:

>        Hi all. Is there an issue with $_GET not handling a Base64-encoded
> value correctly? (PHP is 5.1.6)
>        Am receiving a Base64-encoded value:
>
> theurl.com/index.php?message=xxxxx
>
>  and retrieving it with $_GET:
>
> echo $_GET["message"];
>
> xxxxx is a Japanese phrase, that has been encoded into Base64. So is using
> the + symbol:
>
> ...OODq+OCou...
>
> but my $_GET is replacing the + with a space:
>
> ...OODq OCou...
>
> thus the base64_decode() is failing (displays diamonds with questions marks
> on my Mac).
>
>        The Base64-encoded string is 156 characters long, if that has any
> bearing. My test URL is 230 characters in total, less than the "old" 256
> limit.
>        All I can find online is a reference that PHP will no longer assume
> that a space is a +:
>
> <http://ca3.php.net/manual/en/function.base64-decode.php#69298>
>
> but my problem is the opposite - the + symbols are there, but the GET is
> removing them.
>        (And to add a wrinkle, this then goes into a Joomla! page, whose
> getVar() command completely removes the +, so I couldn't even do a string
> replace, as I don't know where the + should have been!)
>
>        Tired of looking at the dark red spot on the wall! Thanks.
>
>
> George Langley    Multimedia Developer    Audio/Video Editor    Musician,
> Arranger, Composer www.georgelangley.ca
>
>
>
Get variables are automatically urldecoded:
http://php.net/manual/en/function.urldecode.php

The '+' character is one of the special characters automatically decoded
(normally signifies a space.)  I would try using an encoding scheme that
doen't have collisions with special URL characters, use a different global
array not automatically decoded (POST, SESSION), or cautiously urlencode the
url's '+' chars (string replace all spaces to +) and then perform the base
64 decoding.

-- 
Nephtali:  PHP web framework that functions beautifully
http://nephtaliproject.com