tools/testing/selftests/bpf/progs/test_tc_link.c

   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, &eth, 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, &eth, 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, &eth, 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 }