Bug #16337 Updated: include() does not decode % correctly
| From: | tmorgan-spam at kavi dot com | Date: | Wed, 10 Jul 2002 06:10:04 +0000 |
| Subject: | Bug #16337 Updated: include() does not decode % correctly | ||
| References: | 1 | Groups: | php.bugs |
| Request: | Send a blank email to php-bugs+get-13687@lists.php.net to get a copy of this message | ||
ID: 16337
Updated by: tmorgan-spam@kavi.com
Reported By: tmorgan-spam@kavi.com
Status: Verified
Bug Type: HTTP related
Operating System: Unix based
PHP Version: 4.3.0-dev
New Comment:
Regarding base64 encoding:
Yes, the HTTP spec does use b64 for wrapping up username:password
pairs. However, you must remember that A: the URL syntax is you see in
a browser is much different from the data that is passed to a webserver
in HTTP.
B: the http://USERNAME:PASSWORD@domain.tld/
syntax is more of a
defacto-standard-made-legit, and the parsing of it really has nothing
to do with HTTP.
Let me explain more by example. Say my username was the literal
USERNAME, and my password was the literal PASSWORD. then the encoded
pair is: VVNFUk5BTUU6UEFTU1dPUkQ=
that would make my request URL look like:
http://VVNFUk5BTUU6UEFTU1dPUkQ=@www.example.org/
Isn't that a little weird? Does the parser handle '=' before the @?
maybe, but I don't think this syntax is what is originally intended...
So, if instead you mean to encode each of the two tokens seperately,
then the parser would have to unencode b64 and re-encode them again
with the ':' in the middle.
Therefore, does it really matter what encoding is used the first time
through? It is undone anyway. To me, it only makes sense to use URL
encoding, since that is what we are talking about here. We need to
escape characters that would otherwise be considered special in a URL.
<rant>
Every syntax has a set of special characters. When embedding user data
that uses those characters, those characters must be escaped or quoted.
This is a simple principle that 90% of web developers haven't caught
onto yet, and that is why the internet is plagued with cross site
scripting vulnerabilities. (And SQL injection, and shell injection,
and...)
</rant>
Previous Comments:
------------------------------------------------------------------------
[2002-07-09 23:46:35] sniper@php.net
The bug can be found here:
It's partly php_url_parse's fault. It uses regexps
to separate the url parts..but will fail if you pass it
a url like this:
http://username:pass@word@www.example.org/
This will end up as having username 'username' and password 'pass'.
(host being word@www.example.org)
Now, if the username and password are urlencoded (or base64 encoded)
the above mentioned regexp will work..but this will fail:
ext/standard/http_fopen_wrapper.c:150-165
As it goes and base64-encodes the user/password pair.
So, which should be fixed? Let user pass the username/password without
modifying them first (fix the regexps) or require them to be urlencoded
and decode them
before base64 encoding ??
------------------------------------------------------------------------
[2002-07-09 20:59:06] eru@php.net
Judging from the RFC, I'd say you're not using the appropriate encoding
scheme. The RFC says:
base64-user-pass = <base64 encoding of user-pass>
user-pass = userid ":" password
userid = *<TEXT excluding ":">
password = *TEXT
So in your case this would be
$user_pass64 = base64_encode( $username.":".$password );
include("http://".$user_pass64."@www.example.com/");
------------------------------------------------------------------------
[2002-07-09 20:34:34] tmorgan-spam@kavi.com
You know, I would really like this bug fixed, but I am really
frustrated by the attitude I am getting here. Three and a half months
have passed, and yet not a single developer at PHP has taken 10 minutes
to attempt to replicate it themselves. I know there are a lot of bugs
in PHP that need fixing, but cmon, at least an assessment of when it is
going to be fixed. And if it IS fixed in the new release, then why
don't you tell me that?
As for example code, well, I have already given the one line that is
necessary, but I will try to make it plainer:
// GIVEN: user provided $username & $password
// What SHOULD work:
$clean_username = urlencode($username);
$clean_password = urlencode($password);
include("http://$clean_username:$clean_password@www.example.com/");
The url parser in include() needs to parse, then decode, those two
strings before passing them to the HTTP session. If you want to know
why this should be this way, read my previous comments.
------------------------------------------------------------------------
[2002-07-09 19:51:46] sniper@php.net
First, try this snapshot:
http://snaps.php.net/php4-latest.tar.gz
And if this doesn't work like you think it should work,
provide a short but complete script which clearly (!) demonstrates the
possible bug.
------------------------------------------------------------------------
[2002-05-14 01:42:13] tmorgan-spam@kavi.com
We are still having issues with this. If you require any additional
explanation, or examples, I can give them. Some indication of whether
this is being worked on or not would be nice...
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The remainder of the comments for this report are too long. To view
the rest of the comments, please view the bug report online at
http://bugs.php.net/16337
--
Edit this bug report at http://bugs.php.net/?id=16337&edit=1