tools/testing/selftests/bpf/test_queue_stack_map.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 // Copyright (c) 2018 Politecnico di Torino
   3 #include <stddef.h>
   4 #include <string.h>
   5 #include <linux/bpf.h>
   6 #include <linux/if_ether.h>
   7 #include <linux/ip.h>
   8 #include <linux/pkt_cls.h>
   9 #include "bpf_helpers.h"
  10
  11 int _version SEC("version") = 1;
  12
  13 struct bpf_map_def __attribute__ ((section("maps"), used)) map_in = {
  14         .type = MAP_TYPE,
  15         .key_size = 0,
  16         .value_size = sizeof(__u32),
  17         .max_entries = 32,
  18         .map_flags = 0,
  19 };
  20
  21 struct bpf_map_def __attribute__ ((section("maps"), used)) map_out = {
  22         .type = MAP_TYPE,
  23         .key_size = 0,
  24         .value_size = sizeof(__u32),
  25         .max_entries = 32,
  26         .map_flags = 0,
  27 };
  28
  29 SEC("test")
  30 int _test(struct __sk_buff *skb)
  31 {
  32         void *data_end = (void *)(long)skb->data_end;
  33         void *data = (void *)(long)skb->data;
  34         struct ethhdr *eth = (struct ethhdr *)(data);
  35         __u32 value;
  36         int err;
  37
  38         if (eth + 1 > data_end)
  39                 return TC_ACT_SHOT;
  40
  41         struct iphdr *iph = (struct iphdr *)(eth + 1);
  42
  43         if (iph + 1 > data_end)
  44                 return TC_ACT_SHOT;
  45
  46         err = bpf_map_pop_elem(&map_in, &value);
  47         if (err)
  48                 return TC_ACT_SHOT;
  49
  50         iph->daddr = value;
  51
  52         err = bpf_map_push_elem(&map_out, &iph->saddr, 0);
  53         if (err)
  54                 return TC_ACT_SHOT;
  55
  56         return TC_ACT_OK;
  57 }
  58
  59 char _license[] SEC("license") = "GPL";