net: add a UID to use for ULP socket assignment

Create a UID field and enum that can be used to assign ULPs to
sockets. This saves a set of string comparisons if the ULP id
is known.

For sockmap, which is added in the next patches, a ULP is used to
hook into TCP sockets close state. In this case the ULP being added
is done at map insert time and the ULP is known and done on the kernel
side. In this case the named lookup is not needed. Because we don't
want to expose psock internals to user space socket options a user
visible flag is also added. For TLS this is set for BPF it will be
cleared.

Alos remove pr_notice, user gets an error code back and should check
that rather than rely on logs.

Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

1 files changed, 6 insertions, 0 deletions

diff --git a/include/net/tcp.h b/include/net/tcp.h
index 5827866..a58292d 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -1983,6 +1983,10 @@ enum hrtimer_restart tcp_pace_kick(struct hrtimer *timer);
 #define TCP_ULP_MAX		128
 #define TCP_ULP_BUF_MAX		(TCP_ULP_NAME_MAX*TCP_ULP_MAX)
 
+enum {
+	TCP_ULP_TLS,
+};
+
 struct tcp_ulp_ops {
 	struct list_head	list;
 
@@ -1991,7 +1995,9 @@ struct tcp_ulp_ops {
 	/* cleanup ulp */
 	void (*release)(struct sock *sk);
 
+	int		uid;
 	char		name[TCP_ULP_NAME_MAX];
+	bool		user_visible;
 	struct module	*owner;
 };
 int tcp_register_ulp(struct tcp_ulp_ops *type);