Add a helper function to get socket cookie in eBPF
Retrieve the socket cookie generated by sock_gen_cookie() from a sk_buff
with a known socket. Generates a new cookie if one was not yet set.If
the socket pointer inside sk_buff is NULL, 0 is returned. The helper
function coud be useful in monitoring per socket networking traffic
statistics and provide a unique socket identifier per namespace.
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Chenbo Feng <fengc@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index ce6f029..cdfc559 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -459,6 +459,12 @@ union bpf_attr {
* Return:
* > 0 length of the string including the trailing NUL on success
* < 0 error
+ *
+ * u64 bpf_bpf_get_socket_cookie(skb)
+ * Get the cookie for the socket stored inside sk_buff.
+ * @skb: pointer to skb
+ * Return: 8 Bytes non-decreasing number on success or 0 if the socket
+ * field is missing inside sk_buff
*/
#define __BPF_FUNC_MAPPER(FN) \
FN(unspec), \
@@ -506,7 +512,8 @@ union bpf_attr {
FN(get_numa_node_id), \
FN(skb_change_head), \
FN(xdp_adjust_head), \
- FN(probe_read_str),
+ FN(probe_read_str), \
+ FN(get_socket_cookie),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call