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// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2023 Isovalent */
#include <stdbool.h>
#include <linux/bpf.h>
#include <linux/if_ether.h>
#include <linux/stddef.h>
#include <linux/if_packet.h>
#include <bpf/bpf_endian.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_core_read.h>
char LICENSE[] SEC("license") = "GPL";
bool seen_tc1;
bool seen_tc2;
bool seen_tc3;
bool seen_tc4;
bool seen_tc5;
bool seen_tc6;
bool seen_tc7;
bool seen_tc8;
bool set_type;
bool seen_eth;
bool seen_host;
bool seen_mcast;
int mark, prio;
unsigned short headroom, tailroom;
SEC("tc/ingress")
int tc1(struct __sk_buff *skb)
{
struct ethhdr eth = {};
if (skb->protocol != __bpf_constant_htons(ETH_P_IP))
goto out;
if (bpf_skb_load_bytes(skb, 0, ð, sizeof(eth)))
goto out;
seen_eth = eth.h_proto == bpf_htons(ETH_P_IP);
seen_host = skb->pkt_type == PACKET_HOST;
if (seen_host && set_type) {
eth.h_dest[0] = 4;
if (bpf_skb_store_bytes(skb, 0, ð, sizeof(eth), 0))
goto fail;
bpf_skb_change_type(skb, PACKET_MULTICAST);
}
out:
seen_tc1 = true;
fail:
return TCX_NEXT;
}
SEC("tc/egress")
int tc2(struct __sk_buff *skb)
{
seen_tc2 = true;
return TCX_NEXT;
}
SEC("tc/egress")
int tc3(struct __sk_buff *skb)
{
seen_tc3 = true;
return TCX_NEXT;
}
SEC("tc/egress")
int tc4(struct __sk_buff *skb)
{
seen_tc4 = true;
return TCX_NEXT;
}
SEC("tc/egress")
int tc5(struct __sk_buff *skb)
{
seen_tc5 = true;
return TCX_PASS;
}
SEC("tc/egress")
int tc6(struct __sk_buff *skb)
{
seen_tc6 = true;
return TCX_PASS;
}
SEC("tc/ingress")
int tc7(struct __sk_buff *skb)
{
struct ethhdr eth = {};
if (skb->protocol != __bpf_constant_htons(ETH_P_IP))
goto out;
if (bpf_skb_load_bytes(skb, 0, ð, sizeof(eth)))
goto out;
if (eth.h_dest[0] == 4 && set_type) {
seen_mcast = skb->pkt_type == PACKET_MULTICAST;
bpf_skb_change_type(skb, PACKET_HOST);
}
out:
seen_tc7 = true;
return TCX_PASS;
}
struct sk_buff {
struct net_device *dev;
};
struct net_device {
unsigned short needed_headroom;
unsigned short needed_tailroom;
};
SEC("tc/egress")
int tc8(struct __sk_buff *skb)
{
struct net_device *dev = BPF_CORE_READ((struct sk_buff *)skb, dev);
seen_tc8 = true;
mark = skb->mark;
prio = skb->priority;
headroom = BPF_CORE_READ(dev, needed_headroom);
tailroom = BPF_CORE_READ(dev, needed_tailroom);
return TCX_PASS;
}