Received: (qmail 64834 invoked by uid 501); 13 Jul 2000 10:58:50 -0000
Message-Id: <20000713105849.64833.qmail@locus.apache.org>
Date: 13 Jul 2000 10:58:49 -0000
From: Johannes Schmidt-Fischer <jsf@InterFace-AG.com>
Reply-To: jsf@InterFace-AG.com
To: submit@bugz.apache.org
Subject: ProxyPassReverse matches hostnames case sensitive
X-Send-Pr-Version: 3.110

>Number:         6306
>Category:       mod_proxy
>Synopsis:       ProxyPassReverse matches hostnames case sensitive
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    apache
>State:          open
>Quarter:
>Keywords:
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Thu Jul 13 04:00:01 PDT 2000
>Closed-Date:
>Last-Modified:
>Originator:     jsf@InterFace-AG.com
>Release:        1.3.11
>Organization:
apache
>Environment:
Suse Linux 6.3 (problem is not os specific btw)
>Description:
When using ProxyPass and ProxyPassReverse for passing through to another HTTP
server and for reversing any redirect information coming back the matching of
the URL returned from that other server is matched by using strncmp() which is
case sensitive and therefore doesn't change the redirect information if the
hostname coming back is not equal to the hostname in the ProxyPassReverse
statement.

In the ProxyPassReverse statement the hostname must be given exactly as it is
returned from that other server, otherwise the given URL will never match. This
is not according to hostnames not being case sensitive in e.g. DNS.
>How-To-Repeat:
You need two HTTP servers (virtual hosts within one server will do I think). In
my example these two servers are named host1.MyDomain.com and host2.MyDomain.com.

Configuration for host1.MyDomain.com in httpd.conf:


ProxyPass / http://host2.mydomain.com/
ProxyPassReverse / http://host2.mydomain.com/

Configuration for host2.MyDomain.com:

The ServerName returned is host2.MyDomain.com.
Let's assume that there is a directory "Documents" in the DocumentRoot directory.

Now I try to access this directory by sending the URL
http://host1.mydomain.com/Documents to the server host1.MyDomain.com. This URL
is transformed by means of ProxyPass and sent to host2.MyDomain.com as
http://host2.mydomain.com/Documents . This other server returns a "permanently
moved" answer with the new location of http://host2.MyDomain.com/Documents/ .
Since this doesn't match with the ProxyPassReverse statement it is sent back as
is to the browser which in turn tries to contact host2.MyDomain.com directly
which might or might not be possible.
>Fix:
The simple solution would be to describe this "feature" in the mod_proxy
documentation (e.g. as a "Caveat").

Otherwise it would be necessary to split a location URL and the ProxyPassReverse
URL (param #2) both into access method, hostname, and (partial) path and to match
those separately (access method and path case sensitive, hostname not case sensitive).
>Release-Note:
>Audit-Trail:
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