How to timestamp incomming IP packets in kernel
I am trying to timestamp all incomming IP packets. For this I am making changes to ip_rcv_finish() function, in Linux/net/ipv4/ip_input.c. Before ip header is checked (iph->ihl > 5).
If the incomming IP packet header lenght is 5, i.e their is no option field available in IP header. How can I allocate memory in IP header to add timestamp infomation.
I have tried using sbk_push(), to allocate extra memory for timestamp. But I am not sure weather this is the right way to timestamp IP packets.