soreuseport: setsockopt SO_ATTACH_REUSEPORT_[CE]BPF

Expose socket options for setting a classic or extended BPF program
for use when selecting sockets in an SO_REUSEPORT group.  These options
can be used on the first socket to belong to a group before bind or
on any socket in the group after bind.

This change includes refactoring of the existing sk_filter code to
allow reuse of the existing BPF filter validation checks.

Signed-off-by: Craig Gallek <kraig@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 9 insertions, 1 deletions

diff --git a/include/net/sock_reuseport.h b/include/net/sock_reuseport.h
index 67d1eb8fd7af..7dda3d7adba8 100644
--- a/include/net/sock_reuseport.h
+++ b/include/net/sock_reuseport.h
@@ -1,6 +1,8 @@
 #ifndef _SOCK_REUSEPORT_H
 #define _SOCK_REUSEPORT_H
 
+#include <linux/filter.h>
+#include <linux/skbuff.h>
 #include <linux/types.h>
 #include <net/sock.h>
 
@@ -9,12 +11,18 @@ struct sock_reuseport {
 
 	u16			max_socks;	/* length of socks */
 	u16			num_socks;	/* elements in socks */
+	struct bpf_prog __rcu	*prog;		/* optional BPF sock selector */
 	struct sock		*socks[0];	/* array of sock pointers */
 };
 
 extern int reuseport_alloc(struct sock *sk);
 extern int reuseport_add_sock(struct sock *sk, const struct sock *sk2);
 extern void reuseport_detach_sock(struct sock *sk);
-extern struct sock *reuseport_select_sock(struct sock *sk, u32 hash);
+extern struct sock *reuseport_select_sock(struct sock *sk,
+					  u32 hash,
+					  struct sk_buff *skb,
+					  int hdr_len);
+extern struct bpf_prog *reuseport_attach_prog(struct sock *sk,
+					      struct bpf_prog *prog);
 
 #endif  /* _SOCK_REUSEPORT_H */