1/* Support functions handling ptrace_scope.
2 Copyright (C) 2019-2020 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#include <support/check.h>
20#include <support/xstdio.h>
21#include <support/xptrace.h>
22
23int
24support_ptrace_scope (void)
25{
26 int ptrace_scope = -1;
27
28#ifdef __linux__
29 /* YAMA may be not enabled. Otherwise it contains a value from 0 to 3:
30 - 0 classic ptrace permissions
31 - 1 restricted ptrace
32 - 2 admin-only attach
33 - 3 no attach */
34 FILE *f = fopen ("/proc/sys/kernel/yama/ptrace_scope", "r");
35 if (f != NULL)
36 {
37 TEST_COMPARE (fscanf (f, "%d", &ptrace_scope), 1);
38 xfclose (f);
39 }
40#endif
41
42 return ptrace_scope;
43}
44