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// SPDX-License-Identifier: GPL-2.0
#include <stdint.h>
#include <stdbool.h>
#include <linux/bpf.h>
#include <linux/stddef.h>
#include <linux/pkt_cls.h>
#include <bpf/bpf_helpers.h>
enum {
dev_src,
dev_dst,
};
struct bpf_map_def SEC("maps") ifindex_map = {
.type = BPF_MAP_TYPE_ARRAY,
.key_size = sizeof(int),
.value_size = sizeof(int),
.max_entries = 2,
};
static __always_inline int get_dev_ifindex(int which)
{
int *ifindex = bpf_map_lookup_elem(&ifindex_map, &which);
return ifindex ? *ifindex : 0;
}
SEC("chk_egress") int tc_chk(struct __sk_buff *skb)
{
return TC_ACT_SHOT;
}
SEC("dst_ingress") int tc_dst(struct __sk_buff *skb)
{
return bpf_redirect_peer(get_dev_ifindex(dev_src), 0);
}
SEC("src_ingress") int tc_src(struct __sk_buff *skb)
{
return bpf_redirect_peer(get_dev_ifindex(dev_dst), 0);
}
char __license[] SEC("license") = "GPL";
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