diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/cgroup_ancestor.c')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/cgroup_ancestor.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/cgroup_ancestor.c b/tools/testing/selftests/bpf/progs/cgroup_ancestor.c new file mode 100644 index 000000000000..8c2deb4fc493 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/cgroup_ancestor.c @@ -0,0 +1,40 @@ +// 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"; |