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
Change-Id: I4e1910810402d9a51df8985346a7a3435dae61a3
Signed-off-by: Florent Revest <revest@chromium.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: KP Singh <kpsingh@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210210111406.785541-2-revest@chromium.org
SOURCE=UPSTREAM(c5dbb89fc2ac013afe67b9e4fcb3743c02b567cd)
BUG=b:153508410
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 8616998..281d0c7 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1857,6 +1857,7 @@
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_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);
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 7f370c8..1276953 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -1668,6 +1668,14 @@
* Return
* A 8-byte long non-decreasing 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
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index cbe16e7..327fba7 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1750,6 +1750,8 @@
return &bpf_skc_to_tcp_request_sock_proto;
case BPF_FUNC_skc_to_udp6_sock:
return &bpf_skc_to_udp6_sock_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 ?
diff --git a/net/core/filter.c b/net/core/filter.c
index 9358bc4..2e1ad8c 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4627,6 +4627,18 @@
.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);
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 7f370c8..1276953 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -1668,6 +1668,14 @@
* Return
* A 8-byte long non-decreasing 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
