1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2023 Isovalent */
3 #include <stdbool.h>
4
5 #include <linux/bpf.h>
6 #include <linux/if_ether.h>
7 #include <linux/stddef.h>
8 #include <linux/if_packet.h>
9 #include <bpf/bpf_endian.h>
10 #include <bpf/bpf_helpers.h>
11
12 char LICENSE[] SEC("license") = "GPL";
13
14 bool seen_tc1;
15 bool seen_tc2;
16 bool seen_tc3;
17 bool seen_tc4;
18 bool seen_tc5;
19 bool seen_tc6;
20 bool seen_tc7;
21
22 bool set_type;
23
24 bool seen_eth;
25 bool seen_host;
26 bool seen_mcast;
27
28 SEC("tc/ingress")
29 int tc1(struct __sk_buff *skb)
30 {
31 struct ethhdr eth = {};
32
33 if (skb->protocol != __bpf_constant_htons(ETH_P_IP))
34 goto out;
35 if (bpf_skb_load_bytes(skb, 0, ð, sizeof(eth)))
36 goto out;
37 seen_eth = eth.h_proto == bpf_htons(ETH_P_IP);
38 seen_host = skb->pkt_type == PACKET_HOST;
39 if (seen_host && set_type) {
40 eth.h_dest[0] = 4;
41 if (bpf_skb_store_bytes(skb, 0, ð, sizeof(eth), 0))
42 goto fail;
43 bpf_skb_change_type(skb, PACKET_MULTICAST);
44 }
45 out:
46 seen_tc1 = true;
47 fail:
48 return TCX_NEXT;
49 }
50
51 SEC("tc/egress")
52 int tc2(struct __sk_buff *skb)
53 {
54 seen_tc2 = true;
55 return TCX_NEXT;
56 }
57
58 SEC("tc/egress")
59 int tc3(struct __sk_buff *skb)
60 {
61 seen_tc3 = true;
62 return TCX_NEXT;
63 }
64
65 SEC("tc/egress")
66 int tc4(struct __sk_buff *skb)
67 {
68 seen_tc4 = true;
69 return TCX_NEXT;
70 }
71
72 SEC("tc/egress")
73 int tc5(struct __sk_buff *skb)
74 {
75 seen_tc5 = true;
76 return TCX_PASS;
77 }
78
79 SEC("tc/egress")
80 int tc6(struct __sk_buff *skb)
81 {
82 seen_tc6 = true;
83 return TCX_PASS;
84 }
85
86 SEC("tc/ingress")
87 int tc7(struct __sk_buff *skb)
88 {
89 struct ethhdr eth = {};
90
91 if (skb->protocol != __bpf_constant_htons(ETH_P_IP))
92 goto out;
93 if (bpf_skb_load_bytes(skb, 0, ð, sizeof(eth)))
94 goto out;
95 if (eth.h_dest[0] == 4 && set_type) {
96 seen_mcast = skb->pkt_type == PACKET_MULTICAST;
97 bpf_skb_change_type(skb, PACKET_HOST);
98 }
99 out:
100 seen_tc7 = true;
101 return TCX_PASS;
102 }
103
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