Commit c5dbb89f authored by Florent Revest's avatar Florent Revest Committed by Alexei Starovoitov
Browse files

bpf: Expose bpf_get_socket_cookie to tracing programs 



This needs a new helper that:
- can work in a sleepable context (using sock_gen_cookie)
- takes a struct sock pointer and checks that it's not NULL

Signed-off-by: default avatarFlorent Revest <revest@chromium.org>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Acked-by: default avatarKP Singh <kpsingh@kernel.org>
Acked-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210210111406.785541-2-revest@chromium.org
parent 07881ccb

include/linux/bpf.h

+1 −0
Original line number Diff line number Diff line
@@ -1885,6 +1885,7 @@ extern const struct bpf_func_proto bpf_per_cpu_ptr_proto; 
extern const struct bpf_func_proto bpf_this_cpu_ptr_proto;

extern const struct bpf_func_proto bpf_ktime_get_coarse_ns_proto;

extern const struct bpf_func_proto bpf_sock_from_file_proto;

extern const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto;



const struct bpf_func_proto *bpf_tracing_func_proto(

	enum bpf_func_id func_id, const struct bpf_prog *prog);

include/uapi/linux/bpf.h

+8 −0
Original line number Diff line number Diff line
@@ -1673,6 +1673,14 @@ union bpf_attr { 
 * 	Return

 * 		A 8-byte long unique number.

 *

 * u64 bpf_get_socket_cookie(struct sock *sk)

 * 	Description

 * 		Equivalent to **bpf_get_socket_cookie**\ () helper that accepts

 * 		*sk*, but gets socket from a BTF **struct sock**. This helper

 * 		also works for sleepable programs.

 * 	Return

 * 		A 8-byte long unique number or 0 if *sk* is NULL.

 *

 * u32 bpf_get_socket_uid(struct sk_buff *skb)

 * 	Return

 * 		The owner UID of the socket associated to *skb*. If the socket

kernel/trace/bpf_trace.c

+2 −0
Original line number Diff line number Diff line
@@ -1760,6 +1760,8 @@ tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) 
		return &bpf_sk_storage_delete_tracing_proto;

	case BPF_FUNC_sock_from_file:

		return &bpf_sock_from_file_proto;

	case BPF_FUNC_get_socket_cookie:

		return &bpf_get_socket_ptr_cookie_proto;

#endif

	case BPF_FUNC_seq_printf:

		return prog->expected_attach_type == BPF_TRACE_ITER ?

net/core/filter.c

+12 −0
Original line number Diff line number Diff line
@@ -4631,6 +4631,18 @@ static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = { 
	.arg1_type	= ARG_PTR_TO_CTX,

};



BPF_CALL_1(bpf_get_socket_ptr_cookie, struct sock *, sk)

{

	return sk ? sock_gen_cookie(sk) : 0;

}



const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto = {

	.func		= bpf_get_socket_ptr_cookie,

	.gpl_only	= false,

	.ret_type	= RET_INTEGER,

	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,

};



BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)

{

	return __sock_gen_cookie(ctx->sk);

tools/include/uapi/linux/bpf.h

+8 −0
Original line number Diff line number Diff line
@@ -1673,6 +1673,14 @@ union bpf_attr { 
 * 	Return

 * 		A 8-byte long unique number.

 *

 * u64 bpf_get_socket_cookie(struct sock *sk)

 * 	Description

 * 		Equivalent to **bpf_get_socket_cookie**\ () helper that accepts

 * 		*sk*, but gets socket from a BTF **struct sock**. This helper

 * 		also works for sleepable programs.

 * 	Return

 * 		A 8-byte long unique number or 0 if *sk* is NULL.

 *

 * u32 bpf_get_socket_uid(struct sk_buff *skb)

 * 	Return

 * 		The owner UID of the socket associated to *skb*. If the socket