samples/bpf/sock_flags_kern.c

   1 #include <uapi/linux/bpf.h>
   2 #include <linux/socket.h>
   3 #include <linux/net.h>
   4 #include <uapi/linux/in.h>
   5 #include <uapi/linux/in6.h>
   6 #include "bpf_helpers.h"
   7
   8 SEC("cgroup/sock1")
   9 int bpf_prog1(struct bpf_sock *sk)
  10 {
  11         char fmt[] = "socket: family %d type %d protocol %d\n";
  12
  13         bpf_trace_printk(fmt, sizeof(fmt), sk->family, sk->type, sk->protocol);
  14
  15         /* block PF_INET6, SOCK_RAW, IPPROTO_ICMPV6 sockets
  16          * ie., make ping6 fail
  17          */
  18         if (sk->family == PF_INET6 &&
  19             sk->type == SOCK_RAW   &&
  20             sk->protocol == IPPROTO_ICMPV6)
  21                 return 0;
  22
  23         return 1;
  24 }
  25
  26 SEC("cgroup/sock2")
  27 int bpf_prog2(struct bpf_sock *sk)
  28 {
  29         char fmt[] = "socket: family %d type %d protocol %d\n";
  30
  31         bpf_trace_printk(fmt, sizeof(fmt), sk->family, sk->type, sk->protocol);
  32
  33         /* block PF_INET, SOCK_RAW, IPPROTO_ICMP sockets
  34          * ie., make ping fail
  35          */
  36         if (sk->family == PF_INET &&
  37             sk->type == SOCK_RAW  &&
  38             sk->protocol == IPPROTO_ICMP)
  39                 return 0;
  40
  41         return 1;
  42 }
  43
  44 char _license[] SEC("license") = "GPL";