On 2014-07-08 20:19:09 (+0800), shhuiw <shhuiw@xxxxxxx> wrote: > DNS loopkup should use UDP packet, and you have to construct UDP request > based on your captured IP addresses in your module. DNS can actually use both TCP and UDP. > And you have to use DNS server fallback lists and time-out control if some DNS > server cannot work well. Yeah. Doing DNS lookups (forward or reverse) is complicated. There's a dns_query function in the kernel (net/dns_resolver), which apparently upcalls into user space, but I'd avoid dealing with DNS in the kernel at all. Just pass the IP address to user space and let it deal with it. There are plenty of DNS libraries available. Odds are you need to pass the resulting information to user space anyway, so you're not really losing anything. What are you trying to accomplish anyway? Regards, Kristof _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies