I want to encode DNS protocol header using C and create a UDP datagram. Lets say I have a query www.google.com.
Can anyone suggest how to go about it?
You can find the header format here - http://www.nersc.gov/~scottc/software/snort/dns%5Fhead.html
+2
A:
RFC 1035 explains the DNS packet format in full detail. Note that the format is designed to be as compact as possible, so there are a lot of bit- and byte-level optimisations that you will have to pay attention to. A proper, robust DNS encoder and decoder is not for the faint of heart.
Greg Hewgill
2009-11-08 18:32:35
Can you suggest any website or book where I can get any help
Bruce
2009-11-08 18:33:49
What do you need help with? Have you read and understood that RFC document?
Greg Hewgill
2009-11-08 18:37:23
yes I have...how to I do the encoding?
Bruce
2009-11-08 18:39:09
The encoding is fully specified in that RFC....
Carl Norum
2009-11-08 18:42:07
I mean how do I code it in C
Bruce
2009-11-08 18:42:51
+2
A:
+1 to RFC 1035. You can take a look on Wireshark: http://www.wireshark.org/ It shows packets in both - binary and decoded view + contains source code in C so you can check how decoding is implemented.
Oleg
2009-11-08 18:46:58
Welcome to Stack Overflow! You're pretty new here, so I thought I'd point out that "+1" means that you would click the up arrow beside a helpful post to increase its vote count. Others will do the same for your posts and that is how you gain reputation.
Greg Hewgill
2009-11-08 18:50:15
@Greg. You know that the only way you can leave a comment before 50 rep is to make an answer, right?
Ewan Todd
2009-11-08 19:09:11
thnx you for the help...I have installed wireshark and I am working on it now
Bruce
2009-11-08 19:18:11