Linux Server Security, Second Edition

This is the Title of the Book, eMatter Edition

Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

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Chapter 6: Securing Domain Name Services (DNS)

Suppose in the fictional named.conf file excerpted in Example 6-11 we see the

following:

allow-transfer { goodmonkeys; };

This statement, which could be nested in either an options{} statement or a zone{}

statement (depending on whether it’s global or zone-specific), says that zone-trans-

fer requests will be honored only if they match the ACL goodmonkeys—i.e., only if

the requests come from 10.10.100.13 and are signed with the key mon_key.

Sources of BIND (and IS Security) Information

The guidelines and techniques we’ve covered here should give you a good start on

securing your BIND server(s). For more in-depth understanding of these techniques,

I strongly recommend you read the BIND v8 Operators’ Guide and the BIND v9

Administrators’ Reference Manual. For me at least, these are among the most useful

documents provided in any OSS package. Another excellent source of BIND security

information is Liu’s “DNS Security” slideshow. The “Resources” section at the end

of this chapter lists information about these and other BIND resources.

Equally important, every BIND user should subscribe to at least one security-advi-

sory email list. BUGTRAQ is my personal favorite, since it’s both timely and inclu-

sive (but it’s also high volume; I recommend ...