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 #include <bpf/bpf_core_read.h> 12 13 char LICENSE[] SEC("license") = "GPL"; 14 15 bool seen_tc1; 16 bool seen_tc2; 17 bool seen_tc3; 18 bool seen_tc4; 19 bool seen_tc5; 20 bool seen_tc6; 21 bool seen_tc7; 22 bool seen_tc8; 23 24 bool set_type; 25 26 bool seen_eth; 27 bool seen_host; 28 bool seen_mcast; 29 30 int mark, prio; 31 unsigned short headroom, tailroom; 32 33 SEC("tc/ingress") 34 int tc1(struct __sk_buff *skb) 35 { 36 struct ethhdr eth = {}; 37 38 if (skb->protocol != __bpf_constant_htons(ETH_P_IP)) 39 goto out; 40 if (bpf_skb_load_bytes(skb, 0, ð, sizeof(eth))) 41 goto out; 42 seen_eth = eth.h_proto == bpf_htons(ETH_P_IP); 43 seen_host = skb->pkt_type == PACKET_HOST; 44 if (seen_host && set_type) { 45 eth.h_dest[0] = 4; 46 if (bpf_skb_store_bytes(skb, 0, ð, sizeof(eth), 0)) 47 goto fail; 48 bpf_skb_change_type(skb, PACKET_MULTICAST); 49 } 50 out: 51 seen_tc1 = true; 52 fail: 53 return TCX_NEXT; 54 } 55 56 SEC("tc/egress") 57 int tc2(struct __sk_buff *skb) 58 { 59 seen_tc2 = true; 60 return TCX_NEXT; 61 } 62 63 SEC("tc/egress") 64 int tc3(struct __sk_buff *skb) 65 { 66 seen_tc3 = true; 67 return TCX_NEXT; 68 } 69 70 SEC("tc/egress") 71 int tc4(struct __sk_buff *skb) 72 { 73 seen_tc4 = true; 74 return TCX_NEXT; 75 } 76 77 SEC("tc/egress") 78 int tc5(struct __sk_buff *skb) 79 { 80 seen_tc5 = true; 81 return TCX_PASS; 82 } 83 84 SEC("tc/egress") 85 int tc6(struct __sk_buff *skb) 86 { 87 seen_tc6 = true; 88 return TCX_PASS; 89 } 90 91 SEC("tc/ingress") 92 int tc7(struct __sk_buff *skb) 93 { 94 struct ethhdr eth = {}; 95 96 if (skb->protocol != __bpf_constant_htons(ETH_P_IP)) 97 goto out; 98 if (bpf_skb_load_bytes(skb, 0, ð, sizeof(eth))) 99 goto out; 100 if (eth.h_dest[0] == 4 && set_type) { 101 seen_mcast = skb->pkt_type == PACKET_MULTICAST; 102 bpf_skb_change_type(skb, PACKET_HOST); 103 } 104 out: 105 seen_tc7 = true; 106 return TCX_PASS; 107 } 108 109 struct sk_buff { 110 struct net_device *dev; 111 }; 112 113 struct net_device { 114 unsigned short needed_headroom; 115 unsigned short needed_tailroom; 116 }; 117 118 SEC("tc/egress") 119 int tc8(struct __sk_buff *skb) 120 { 121 struct net_device *dev = BPF_CORE_READ((struct sk_buff *)skb, dev); 122 123 seen_tc8 = true; 124 mark = skb->mark; 125 prio = skb->priority; 126 headroom = BPF_CORE_READ(dev, needed_headroom); 127 tailroom = BPF_CORE_READ(dev, needed_tailroom); 128 return TCX_PASS; 129 } 130