Sophie: pdns-3.0.1-0.1mdv2010.2 i586

pdns-3.0.1-0.1mdv2010.2.i586.rpm

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>Chapter 7. Security settings &amp; considerations</H1
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><H1
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><A
NAME="SETTINGS"
>7.1. Settings</A
></H1
><P
>PDNS has several options to easily allow it to run more securely. Most notable are the <B
CLASS="COMMAND"
>chroot</B
>, 
	<B
CLASS="COMMAND"
>setuid</B
> and <B
CLASS="COMMAND"
>setgid</B
> options which can be specified.</P
><P
>	For additional information on PowerDNS security, PowerDNS security incidents and PowerDNS security policy, see <A
HREF="security-policy.html"
>Section 1.4</A
>.
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><A
NAME="AEN2952"
>7.1.1. Running as a less privileged identity</A
></H2
><P
>	  By specifying <B
CLASS="COMMAND"
>setuid</B
> and <B
CLASS="COMMAND"
>setgid</B
>, PDNS changes to this identity shortly after
	  binding to the privileged DNS ports. These options are highly recommended. It is suggested that a separate identity
	  is created for PDNS as the user 'nobody' is in fact quite powerful on most systems.
	</P
><P
>	  Both these parameters can be specified either numerically or as real names.
	  You should set these parameters immediately if they are not set!
	</P
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><A
NAME="AEN2958"
>7.1.2. Jailing the process in a chroot</A
></H2
><P
>	  The <B
CLASS="COMMAND"
>chroot</B
> option secures PDNS to its own directory so that even if it should become compromised and
	  under control of external influences, it will have a hard time affecting the rest of the system.
	</P
><P
>	  Even though this will hamper hackers a lot, chroot jails have been known to be broken. 
	</P
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>	      When chrooting PDNS, take care that backends will be able to get to their files. Many databases need access to a UNIX 
	      domain socket which should live within the chroot. It is often possible to hardlink such a socket into the chroot dir.
	    </P
><P
>	      When running with master or slave support, be aware that many operating systems need access to specific libraries
	      (ofen <TT
CLASS="FILENAME"
>/lib/libnss*</TT
>) in order to support resolution of domain names! You can also hardlink these.
	    </P
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>
	</P
><P
>	  The default PDNS configuration is best chrooted to <TT
CLASS="FILENAME"
>./</TT
>, which boils down to the configured location
	  of the controlsocket. 
	</P
><P
>	  This is achieved by adding the following to pdns.conf: <B
CLASS="COMMAND"
>chroot=./</B
>, and restarting PDNS.
	</P
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