Obfuscate GTM's BIND Version
For various reason's, one might wish not to advertise to the world the version of BIND running on the GTM. The fix action is to add two lines to the options section of the named.conf file (See Below). This can be done at the command line by editing /var/named/config/named.conf, or by editing said file via the GUI. If done in the GUI, named is restarted for you, if done at the command line, you'll need restart manually (bigstart restart named). Anway, the lines you'll need to obfuscate the version are:
query-source address * port 53;
version "x.y.z";
You can just leave it blank with "", or you can place a message in there. Whatever text floats your boat. I did a couple queries around the net and got some "I don't think so!" messages, as well several "Contact for version information". Quite a few sites I checked returned BIND version information. This is a standard BIND configuration, so this configuration is not specific to GTM. For this test, I'll start with a query prior to configuring named. Then, I'll set the version name to "Not today, my friend..." and re-query. Results are below.
Before:
user@ubuntu:~$ dig @10.10.20.5 version.bind chaos txt
; DiG 9.5.0-P2 @10.10.20.5 version.bind chaos txt
; (1 server found)
;; global options: printcmd
;; Got answer:
;; ->>HEADER;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 0
;; WARNING: recursion requested but not available;; QUESTION SECTION:
;version.bind. CH TXT;; ANSWER SECTION:
version.bind. 0 CH TXT "9.5.1-P2";; AUTHORITY SECTION:
version.bind. 0 CH NS version.bind.;; Query time: 10 msec
;; SERVER: 10.10.20.5#53(10.10.20.5)
;; WHEN: Sun May 10 12:59:20 2009
;; MSG SIZE rcvd: 65After:
user@ubuntu:~$ dig @10.10.20.5 version.bind chaos txt
; DiG 9.5.0-P2 @10.10.20.5 version.bind chaos txt
; (1 server found)
;; global options: printcmd
;; Got answer:
;; ->>HEADER;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 0
;; WARNING: recursion requested but not available;; QUESTION SECTION:
;version.bind. CH TXT;; ANSWER SECTION:
version.bind. 0 CH TXT "Not today, my friend...";; AUTHORITY SECTION:
version.bind. 0 CH NS version.bind.
;; Query time: 8 msec
;; SERVER: 10.10.20.5#53(10.10.20.5)
;; WHEN: Sun May 10 12:40:43 2009
;; MSG SIZE rcvd: 61
For information on which version of BIND exists on the GTM releases (as well as the other 3rd party software), please reference Solution 9445.
