From: Chenbo Feng <chenbofeng.ker...@gmail.com> Date: Wed, 5 Apr 2017 19:00:54 -0700
> In the current kernel socket cookie implementation, there is no simple > and direct way to retrieve the socket cookie based on file descriptor. A > process mat need to get it from sock fd if it want to correlate with > sock_diag output or use a bpf map with new socket cookie function. > > If userspace wants to receive the socket cookie for a given socket fd, > it must send a SOCK_DIAG_BY_FAMILY dump request and look for the 5-tuple. > This is slow and can be ambiguous in the case of sockets that have the > same 5-tuple (e.g., tproxy / transparent sockets, SO_REUSEPORT sockets, > etc.). > > As shown in the example program. The xt_eBPF program is using socket cookie > to record the network traffics statistics and with the socket cookie > retrieved by getsockopt. The program can directly access to a specific > socket data without scanning the whole bpf map. Series applied, thank you.