LXR linux/tools/testing/selftests/bpf/progs/test_skmsg_load

   1// SPDX-License-Identifier: GPL-2.0
   2// Copyright (c) 2020 Isovalent, Inc.
   3#include "vmlinux.h"
   4#include <bpf/bpf_helpers.h>
   5
   6struct {
   7        __uint(type, BPF_MAP_TYPE_SOCKMAP);
   8        __uint(max_entries, 2);
   9        __type(key, __u32);
  10        __type(value, __u64);
  11} sock_map SEC(".maps");
  12
  13struct {
  14        __uint(type, BPF_MAP_TYPE_SOCKHASH);
  15        __uint(max_entries, 2);
  16        __type(key, __u32);
  17        __type(value, __u64);
  18} sock_hash SEC(".maps");
  19
  20struct {
  21        __uint(type, BPF_MAP_TYPE_SK_STORAGE);
  22        __uint(map_flags, BPF_F_NO_PREALLOC);
  23        __type(key, __u32);
  24        __type(value, __u64);
  25} socket_storage SEC(".maps");
  26
  27SEC("sk_msg")
  28int prog_msg_verdict(struct sk_msg_md *msg)
  29{
  30        struct task_struct *task = (struct task_struct *)bpf_get_current_task();
  31        int verdict = SK_PASS;
  32        __u32 pid, tpid;
  33        __u64 *sk_stg;
  34
  35        pid = bpf_get_current_pid_tgid() >> 32;
  36        sk_stg = bpf_sk_storage_get(&socket_storage, msg->sk, 0, BPF_SK_STORAGE_GET_F_CREATE);
  37        if (!sk_stg)
  38                return SK_DROP;
  39        *sk_stg = pid;
  40        bpf_probe_read_kernel(&tpid , sizeof(tpid), &task->tgid);
  41        if (pid != tpid)
  42                verdict = SK_DROP;
  43        bpf_sk_storage_delete(&socket_storage, (void *)msg->sk);
  44        return verdict;
  45}
  46
  47char _license[] SEC("license") = "GPL";
  48