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// SPDX-License-Identifier: GPL-2.0
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
struct {
__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
__uint(max_entries, 3);
__uint(key_size, sizeof(__u32));
__uint(value_size, sizeof(__u32));
} jmp_table SEC(".maps");
#define TAIL_FUNC(x) \
SEC("classifier/" #x) \
int bpf_func_##x(struct __sk_buff *skb) \
{ \
return x; \
}
TAIL_FUNC(0)
TAIL_FUNC(1)
TAIL_FUNC(2)
SEC("classifier")
int entry(struct __sk_buff *skb)
{
/* Multiple locations to make sure we patch
* all of them.
*/
bpf_tail_call_static(skb, &jmp_table, 0);
bpf_tail_call_static(skb, &jmp_table, 0);
bpf_tail_call_static(skb, &jmp_table, 0);
bpf_tail_call_static(skb, &jmp_table, 0);
bpf_tail_call_static(skb, &jmp_table, 1);
bpf_tail_call_static(skb, &jmp_table, 1);
bpf_tail_call_static(skb, &jmp_table, 1);
bpf_tail_call_static(skb, &jmp_table, 1);
bpf_tail_call_static(skb, &jmp_table, 2);
bpf_tail_call_static(skb, &jmp_table, 2);
bpf_tail_call_static(skb, &jmp_table, 2);
bpf_tail_call_static(skb, &jmp_table, 2);
return 3;
}
char __license[] SEC("license") = "GPL";
int _version SEC("version") = 1;
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