apache-api/3854: apache lacks hook for output stream "filter" modules in api

[Rainer Scherg <Ra...@t-online.de>]

>Number:         3854
>Category:       apache-api
>Synopsis:       apache lacks hook for output stream "filter" modules in api
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    apache
>State:          open
>Class:          change-request
>Submitter-Id:   apache
>Arrival-Date:   Sun Feb  7 08:30:00 PST 1999
>Last-Modified:
>Originator:     Rainer.Scherg@t-online.de
>Organization:
apache
>Release:        1.3.4
>Environment:
any
>Description:
Right now it's very difficult to implement a filter module in the
(http) output stream of apache. Developing a third party module, which
is able to examine - e.g. the proxy http content stream, can only be developed
by providing a simple - but version dependend - patch to the orig.
apache source code.

E.g.: a school (minors) is using apache proxy to connect to their network
to the internet. There may be a demand of filtering software to prevend
kids of viewing "harzardous" contents. The ProxyBlock directive cannot handle
the contents of html pages, only some servers in the internet.

By providing a hook into the datastream this could be handled by a better way.

IMO, the hook should call a filter function, which should be able to handle
the stream (buffer) in partial steps. The funtion should return a code which
indicates the server whether stream was modified, unmodified, or the server
has to cancel the request (blocked & reason).

I know this is a request which could lead to a very controverse discussion,
but IMO it's very usefull and will enhance apache by a powerfull feature
(e.g. build in virus scanner for proxies on exe files, etc.).

Rainer
>How-To-Repeat:

>Fix:

>Audit-Trail:
>Unformatted:
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