I have a mod_perl handler that I wrote some time ago that I'm now reviewing from the POV of security. It starts roughly like this: 

sub handler
{
    my $r = shift;

    local ($NS::IP_address,
           %NS::params,
           %NS::cookies);

    .
    .
    $NS::IP_address = $r->connection()->remote_ip();
    .
    .
}

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i.e. it localizes some variables in a namespace and then assigns to them, making them globally available throughout the handler.

At the end of the handler, my reasoning was that the dynamic scoping of those variables would ensure that their contents are no longer available to any later request. However, given that those some of those variables contain sensitive data (usernames and password (hashes)), I'd like to be sure that I'm not missing some obvious reason why this could fail in a mod_perl environment.

Any mod_perl gurus out there who can give a definitive yay-or-nay to my approach above ?

Steve Collyer

In reply to mod_perl: globals and security question by scollyer

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