41 lines
903 B
C
41 lines
903 B
C
|
// SPDX-License-Identifier: GPL-2.0
|
||
|
|
// Copyright (c) 2018 Facebook
|
||
|
|
|
||
|
|
#include <vmlinux.h>
|
||
|
|
#include <bpf/bpf_helpers.h>
|
||
|
|
#include <bpf/bpf_core_read.h>
|
||
|
|
#include "bpf_tracing_net.h"
|
||
|
|
#define NUM_CGROUP_LEVELS 4
|
||
|
|
|
||
|
|
__u64 cgroup_ids[NUM_CGROUP_LEVELS];
|
||
|
|
__u16 dport;
|
||
|
|
|
||
|
|
static __always_inline void log_nth_level(struct __sk_buff *skb, __u32 level)
|
||
|
|
{
|
||
|
|
/* [1] &level passed to external function that may change it, it's
|
||
|
|
* incompatible with loop unroll.
|
||
|
|
*/
|
||
|
|
cgroup_ids[level] = bpf_skb_ancestor_cgroup_id(skb, level);
|
||
|
|
}
|
||
|
|
|
||
|
|
SEC("tc")
|
||
|
|
int log_cgroup_id(struct __sk_buff *skb)
|
||
|
|
{
|
||
|
|
struct sock *sk = (void *)skb->sk;
|
||
|
|
|
||
|
|
if (!sk)
|
||
|
|
return TC_ACT_OK;
|
||
|
|
|
||
|
|
sk = bpf_core_cast(sk, struct sock);
|
||
|
|
if (sk->sk_protocol == IPPROTO_UDP && sk->sk_dport == dport) {
|
||
|
|
log_nth_level(skb, 0);
|
||
|
|
log_nth_level(skb, 1);
|
||
|
|
log_nth_level(skb, 2);
|
||
|
|
log_nth_level(skb, 3);
|
||
|
|
}
|
||
|
|
|
||
|
|
return TC_ACT_OK;
|
||
|
|
}
|
||
|
|
|
||
|
|
char _license[] SEC("license") = "GPL";
|