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

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <stdint.h>
   3 #include <stdbool.h>
   4
   5 #include <linux/bpf.h>
   6 #include <linux/stddef.h>
   7 #include <linux/pkt_cls.h>
   8
   9 #include <bpf/bpf_helpers.h>
  10
  11 enum {
  12         dev_src,
  13         dev_dst,
  14 };
  15
  16 struct bpf_map_def SEC("maps") ifindex_map = {
  17         .type           = BPF_MAP_TYPE_ARRAY,
  18         .key_size       = sizeof(int),
  19         .value_size     = sizeof(int),
  20         .max_entries    = 2,
  21 };
  22
  23 static __always_inline int get_dev_ifindex(int which)
  24 {
  25         int *ifindex = bpf_map_lookup_elem(&ifindex_map, &which);
  26
  27         return ifindex ? *ifindex : 0;
  28 }
  29
  30 SEC("chk_egress") int tc_chk(struct __sk_buff *skb)
  31 {
  32         return TC_ACT_SHOT;
  33 }
  34
  35 SEC("dst_ingress") int tc_dst(struct __sk_buff *skb)
  36 {
  37         return bpf_redirect_peer(get_dev_ifindex(dev_src), 0);
  38 }
  39
  40 SEC("src_ingress") int tc_src(struct __sk_buff *skb)
  41 {
  42         return bpf_redirect_peer(get_dev_ifindex(dev_dst), 0);
  43 }
  44
  45 char __license[] SEC("license") = "GPL";