I am writing a code as follows
$ID= 1; #2 octets
$flags = 0; #(For Request value is 0)#2 octets
$QDCOUNT=1; #2 octets
$ANCOUNT=0;#2 octets
$NSCOUNT=0;#2 octets
$ARCOUNT=0;#2 octets
$QNAME= "www.google.com";#16 octets
$QTYPE=23; #(For NAPTR)#2 octets
$QCLASS=1; #(For IN)#2 octet


my $DNS_Request= "$ID$flags$QDCOUNT$ANCOUNT$NSCOUNT$ARCOUNT$QNAME$QTYP
+E$QCLASS";


$MySocket->send($DNS_Request);

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Here the problem is that Suppose i am assigning the value $ID=1. How can can i convert it into the hexa value of 2 octets which is '0001' and so for other values with their respective octets.

The $QNAME = "www.google.com". How can i convert it into the hexa value '0377777706676F6F676C6503636F6D00'.

So that Wire shark will decoded it properly without showing malformed packet.

The problem is that if i am sending the $QNAME value diretly (That means without converting into the hexa format). The wireshark decoded it as '7777772e676F6F676C652e636F6D'.Which shows it as a malformed packet.

Plz suggest me a suitable code. So that i can send a DNS request properly.

Regd's
Sanjay

In reply to How to create a DNS message in perl? by sanjay nayak

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