Re: mod_perl and cgi-script handler

Addendum :

This is independent of the other previous explanations.

If your cgi-bin scripts happen to be written in perl, then you would get a rather 
important *response* performance improvement by using

<Directory /var/www/my-server-name/cgi-bin>
   SetHandler perl-script
   PerlResponseHandler ModPerl::Registry
..
</Directory>

That is because then, the first time your script is called, mod_perl would compile it, and 
save the (pre-)compiled code in memory. And the next time your script is called, the 
Apache-embedded perl interpreter would just run the pre-compiled code.

One drawback is memory : each of the Apache "children" will now store a pre-compiled copy 
of every perl cgi-bin script that has been run since this child was started. But if your 
scripts are run many times, the performance improvement is really dramatic.


On 11.06.2017 11:36, André Warnier (tomcat) wrote:
> Hi.
>
> Now that you mention this, I believe that the original "mistake" in your configuration
> was the
>
> <Directory /var/www/my-server-name/cgi-bin>
> ..
>     SetHandler modperl
> ..
> </Directory>
>
> and by just taking that line out, you would have the same effect (without the <FilesMatch>).
> SetHandler is the line which originally overrides the effect of "ScriptAlias".
>
> You do not need "SetHandler modperl" in order to do the authentication via your module.
> The "PerlAuthenHandler" is all that is needed.
>
> SetHandler applies to the Apache response-generation phase, which comes later than the AAA
> phase.
>
> To explain this in another way :
>
> What you are now doing below is :
>
> 1) ScriptAlias /cgi-bin/ "/var/www/my-server-name/cgi-bin/"
>
> That does the same as :
> Alias /cgi-bin/ "/var/www/my-server-name/cgi-bin/"
> plus
> <Directory /var/www/my-server-name/cgi-bin/>
>    SetHandler cgi-script
> <Directory>
>
> It sets the Apache response-generating module to be mod_cgi, instead of the default (which
> serves static pages).
> See :
> http://httpd.apache.org/docs/2.4/mod/mod_alias.html#scriptalias
> http://httpd.apache.org/docs/2.4/mod/mod_cgi.html
>
> 2) SetHandler modperl
>
> This overrides the "cgi-script" response handler which you set above, to set mod_perl
> instead.  mod_perl would now expect an additional directive
> PerlResponseHandler (some perl sub/method).
> See : http://perl.apache.org/docs/2.0/user/config/config.html#C_SetHandler_
>
> 3) <FilesMatch>
>    SetHandler cgi-script
>
> By doing this, you are resetting the response handler again, from mod_perl back to
> cgi-script (mod_cgi).
>
>
> So instead, if you just omit
>    SetHandler modperl
>
> it would be simpler, and just as effective.
>
> And if you want even more info about what is happening, see the following :
> https://perl.apache.org/docs/2.0/user/handlers/http.html
> (Note : the AAA part there is outdated for Apache 2.4)
>
> On 11.06.2017 01:47, Jie Gao wrote:
>> It seemed "SetHandler" in the mod_perl section overwrote the settings for cgi-script.
>> Adding the following to the directory stanza fixed the problem:
>>
>>      <FilesMatch .*>
>>          SetHandler cgi-script
>>      </FilesMatch>
>>
>> ..
>>
>> Regards,
>>
>>
>> Jie
>>
>>
>>
>> * Jie Gao <[email protected]> wrote:
>>
>>> Date: Fri, 9 Jun 2017 20:35:43 +1000
>>> From: Jie Gao <[email protected]>
>>> To: [email protected]
>>> Subject: mod_perl and cgi-script handler
>>> User-Agent: Mutt/1.5.24 (2015-08-30)
>>>
>>> Hi All
>>>
>>> I have run into a problem with CGI under mod_perl, and I can't get my head around it.
>>>
>>> I wanted to put a "cgi-bin" directory under my authentication/authorisation handlers,
>>> but while authen/authz works fine (debug showing access granted), the directory is in
>>> the end not handled by "cgi-script", the default cgid content handler, and the text of
>>> the cgi script gets displayed instead.
>>>
>>> My configuration is like the following:
>>>
>>> #------------------------------------------------------------
>>>
>>> PerlAddAuthzProvider my_User W::W::Authnz->authz
>>>
>>> <VirtualHost _default_:443>
>>> ...
>>> ScriptAlias /cgi-bin/ "/var/www/my-server-name/cgi-bin/"
>>>
>>> <Directory /var/www/my-server-name/cgi-bin>
>>>      AllowOverride None
>>>
>>> #    PerlOptions +SetupEnv
>>> #    Options +ExecCGI
>>> #    SetHandler modperl
>>> #    PerlAuthenHandler W::W::Authnz->authen
>>> #    AuthType mytype
>>> #    AuthName 'myname'
>>> #    <RequireAll>
>>> #    Require my_User mylogin
>>> #    Require ip 10.65.
>>> #    </RequireAll>
>>> </Directory>
>>>
>>> </VirtualHost>
>>>
>>> #------------------------------------------------------------
>>>
>>> If I comment out, as above, all the mod_perl configurations, and then add "Require all
>>> granted" to the directory stanza, the cgi scripts will run normally.
>>>
>>> Any tips/pointers as to where else I should look would be much appreciated.
>>>
>>> Regards,
>>>
>>>
>>>
>>> Jie
>>>
>>
>