net: sock: allow eBPF programs to be attached to sockets

introduce new setsockopt() command:

setsockopt(sock, SOL_SOCKET, SO_ATTACH_BPF, &prog_fd, sizeof(prog_fd))

where prog_fd was received from syscall bpf(BPF_PROG_LOAD, attr, ...)
and attr->prog_type == BPF_PROG_TYPE_SOCKET_FILTER

setsockopt() calls bpf_prog_get() which increments refcnt of the program,
so it doesn't get unloaded while socket is using the program.

The same eBPF program can be attached to multiple sockets.

User task exit automatically closes socket which calls sk_filter_uncharge()
which decrements refcnt of eBPF program

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Alexei Starovoitov 2014-12-01 15:06:35 -08:00 committed by David S. Miller
parent ddd872bc30
commit 89aa075832
18 changed files with 155 additions and 2 deletions

View file

@ -89,4 +89,7 @@
#define SO_INCOMING_CPU 49
#define SO_ATTACH_BPF 50
#define SO_DETACH_BPF SO_DETACH_FILTER
#endif /* _ASM_POWERPC_SOCKET_H */