AFAIK, arpd is used to offload certain jobs and memory footprint from kernel. The arpd process can get packets from two sockets: notification messages from kernel via NETLINK regular ARP packets such as ARP_REPLY from the host's neighbors, via a PF_PACKET socket . My question is, how are ARP packets delivered to a userspace socket? When network stack receives an ARP packet, it passes it to arp_rcv() and arp_process() kernel functions, but I wasn't able to locate any code that sends packet to the PF_PACKET socket that arpd registered. I am sure I missed something here..

Which function sends ARP packet to ARPD daemon in Linux kernel?

AFAIK, arpd is used to offload certain jobs and memory footprint from kernel. The arpd process can get packets from two sockets:

notification messages from kernel via NETLINK
regular ARP packets such as ARP_REPLY from the host's neighbors, via a PF_PACKET socket.

My question is, how are ARP packets delivered to a userspace socket? When network stack receives an ARP packet, it passes it to arp_rcv() and arp_process() kernel functions, but I wasn't able to locate any code that sends packet to the PF_PACKET socket that arpd registered. I am sure I missed something here..

Which function sends ARP packet to ARPD daemon in Linux kernel?

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