64 lines
1.3 KiB
C
64 lines
1.3 KiB
C
// 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 <linux/if_ether.h>
|
|
#include <linux/ip.h>
|
|
|
|
#include <bpf/bpf_helpers.h>
|
|
|
|
volatile const __u32 IFINDEX_SRC;
|
|
volatile const __u32 IFINDEX_DST;
|
|
|
|
static const __u8 src_mac[] = {0x00, 0x11, 0x22, 0x33, 0x44, 0x55};
|
|
static const __u8 dst_mac[] = {0x00, 0x22, 0x33, 0x44, 0x55, 0x66};
|
|
|
|
SEC("tc")
|
|
int tc_chk(struct __sk_buff *skb)
|
|
{
|
|
return TC_ACT_SHOT;
|
|
}
|
|
|
|
SEC("tc")
|
|
int tc_dst(struct __sk_buff *skb)
|
|
{
|
|
return bpf_redirect_peer(IFINDEX_SRC, 0);
|
|
}
|
|
|
|
SEC("tc")
|
|
int tc_src(struct __sk_buff *skb)
|
|
{
|
|
return bpf_redirect_peer(IFINDEX_DST, 0);
|
|
}
|
|
|
|
SEC("tc")
|
|
int tc_dst_l3(struct __sk_buff *skb)
|
|
{
|
|
return bpf_redirect(IFINDEX_SRC, 0);
|
|
}
|
|
|
|
SEC("tc")
|
|
int tc_src_l3(struct __sk_buff *skb)
|
|
{
|
|
__u16 proto = skb->protocol;
|
|
|
|
if (bpf_skb_change_head(skb, ETH_HLEN, 0) != 0)
|
|
return TC_ACT_SHOT;
|
|
|
|
if (bpf_skb_store_bytes(skb, 0, &src_mac, ETH_ALEN, 0) != 0)
|
|
return TC_ACT_SHOT;
|
|
|
|
if (bpf_skb_store_bytes(skb, ETH_ALEN, &dst_mac, ETH_ALEN, 0) != 0)
|
|
return TC_ACT_SHOT;
|
|
|
|
if (bpf_skb_store_bytes(skb, ETH_ALEN + ETH_ALEN, &proto, sizeof(__u16), 0) != 0)
|
|
return TC_ACT_SHOT;
|
|
|
|
return bpf_redirect_peer(IFINDEX_DST, 0);
|
|
}
|
|
|
|
char __license[] SEC("license") = "GPL";
|