David Fletcher | 11 Jul 20:34
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Chroot and name resolution with PHP

Hi,

I'm using mod_security-1.8.3, with Apache httpd-2.0.50 and PHP 4.3.7 on
Slackware linux.

In one of my PHP scripts I use the fsockopen function, which requires a
name (e.g www.example.com) to be resolved. This works fine if I do not use
the chroot capabilities of mod_security. However, with the chroot running,
I get errors like 

Warning: fsockopen(): php_network_getaddresses: getaddrinfo failed: Name
or service not known

Adding these files to the chroot gets rid of the problem:

/chroot/apache/lib/libnss_dns.so.2
/chroot/apache/libnss_files.so.2
/chroot/apache/libresolv.so.2
/chroot/apache/etc/resolv.conf

Everything else in the chroot work really well using mod_security, without
having to find all the libraries and put them in the chroot. That's what I
really like about mod_security!

Is there some way to avoid the need to put these name resolution libraries
in the chroot?

Thanks for any help,

David Fletcher.

--

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Email: David at megapico dot co dot uk
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