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

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (c) 2023, SUSE. */
   3
   4 #include "vmlinux.h"
   5 #include <bpf/bpf_tracing.h>
   6 #include "bpf_tracing_net.h"
   7
   8 char _license[] SEC("license") = "GPL";
   9 int pid;
  10
  11 SEC("fmod_ret/update_socket_protocol")
  12 int BPF_PROG(mptcpify, int family, int type, int protocol)
  13 {
  14         if (bpf_get_current_pid_tgid() >> 32 != pid)
  15                 return protocol;
  16
  17         if ((family == AF_INET || family == AF_INET6) &&
  18             type == SOCK_STREAM &&
  19             (!protocol || protocol == IPPROTO_TCP)) {
  20                 return IPPROTO_MPTCP;
  21         }
  22
  23         return protocol;
  24 }