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1// SPDX-License-Identifier: GPL-2.02#include <linux/bpf.h>3#include <bpf/bpf_helpers.h>4#include "bpf_legacy.h"5#include "bpf_misc.h"6 7struct {8 __uint(type, BPF_MAP_TYPE_PROG_ARRAY);9 __uint(max_entries, 2);10 __uint(key_size, sizeof(__u32));11 __uint(value_size, sizeof(__u32));12} jmp_table SEC(".maps");13 14__noinline15int subprog_tail2(struct __sk_buff *skb)16{17 volatile char arr[64] = {};18 19 if (load_word(skb, 0) || load_half(skb, 0))20 bpf_tail_call_static(skb, &jmp_table, 10);21 else22 bpf_tail_call_static(skb, &jmp_table, 1);23 24 __sink(arr[sizeof(arr) - 1]);25 26 return skb->len;27}28 29static __noinline30int subprog_tail(struct __sk_buff *skb)31{32 volatile char arr[64] = {};33 34 bpf_tail_call_static(skb, &jmp_table, 0);35 36 __sink(arr[sizeof(arr) - 1]);37 38 return skb->len * 2;39}40 41SEC("tc")42int classifier_0(struct __sk_buff *skb)43{44 volatile char arr[128] = {};45 46 __sink(arr[sizeof(arr) - 1]);47 48 return subprog_tail2(skb);49}50 51SEC("tc")52int classifier_1(struct __sk_buff *skb)53{54 volatile char arr[128] = {};55 56 __sink(arr[sizeof(arr) - 1]);57 58 return skb->len * 3;59}60 61SEC("tc")62int entry(struct __sk_buff *skb)63{64 volatile char arr[128] = {};65 66 __sink(arr[sizeof(arr) - 1]);67 68 return subprog_tail(skb);69}70 71char __license[] SEC("license") = "GPL";72