1 | /* Basic test for gethostid. |
2 | Copyright (C) 2018-2022 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 <gnu/lib-names.h> |
20 | #include <nss.h> |
21 | #include <stdio.h> |
22 | #include <stdlib.h> |
23 | #include <string.h> |
24 | #include <support/namespace.h> |
25 | #include <support/support.h> |
26 | #include <support/temp_file.h> |
27 | #include <support/xdlfcn.h> |
28 | #include <support/xstdio.h> |
29 | #include <support/xunistd.h> |
30 | #include <unistd.h> |
31 | |
32 | /* Initial test is run outside a chroot, to increase the likelihood of |
33 | success. */ |
34 | static void |
35 | outside_chroot (void *closure) |
36 | { |
37 | long id = gethostid (); |
38 | printf (format: "info: host ID outside chroot: 0x%lx\n" , id); |
39 | } |
40 | |
41 | /* The same, but this time perform a chroot operation. */ |
42 | static void |
43 | in_chroot (void *closure) |
44 | { |
45 | const char *chroot_path = closure; |
46 | xchroot (path: chroot_path); |
47 | long id = gethostid (); |
48 | printf (format: "info: host ID in chroot: 0x%lx\n" , id); |
49 | } |
50 | |
51 | static int |
52 | do_test (void) |
53 | { |
54 | support_isolate_in_subprocess (callback: outside_chroot, NULL); |
55 | |
56 | /* Now run the test inside a chroot. */ |
57 | support_become_root (); |
58 | if (!support_can_chroot ()) |
59 | /* Cannot perform further tests. */ |
60 | return 0; |
61 | |
62 | /* Only use nss_files. */ |
63 | __nss_configure_lookup (dbname: "hosts" , string: "files" ); |
64 | |
65 | /* Load the DSO outside of the chroot. */ |
66 | xdlopen (LIBNSS_FILES_SO, RTLD_LAZY); |
67 | |
68 | char *chroot_dir = support_create_temp_directory (base: "tst-gethostid-" ); |
69 | support_isolate_in_subprocess (callback: in_chroot, closure: chroot_dir); |
70 | |
71 | /* Tests with /etc/hosts in the chroot. */ |
72 | { |
73 | char *path = xasprintf (format: "%s/etc" , chroot_dir); |
74 | add_temp_file (name: path); |
75 | xmkdir (path, 0777); |
76 | free (ptr: path); |
77 | path = xasprintf (format: "%s/etc/hosts" , chroot_dir); |
78 | add_temp_file (name: path); |
79 | |
80 | FILE *fp = xfopen (path, mode: "w" ); |
81 | xfclose (fp); |
82 | printf (format: "info: chroot test with an empty /etc/hosts file\n" ); |
83 | support_isolate_in_subprocess (callback: in_chroot, closure: chroot_dir); |
84 | |
85 | char hostname[1024]; |
86 | int ret = gethostname (name: hostname, len: sizeof (hostname)); |
87 | if (ret < 0) |
88 | printf (format: "warning: invalid result from gethostname: %d\n" , ret); |
89 | else if (strlen (hostname) == 0) |
90 | puts (s: "warning: gethostname returned empty string" ); |
91 | else |
92 | { |
93 | printf (format: "info: chroot test with IPv6 address in /etc/hosts for: %s\n" , |
94 | hostname); |
95 | fp = xfopen (path, mode: "w" ); |
96 | /* Use an IPv6 address to induce another lookup failure. */ |
97 | fprintf (fp, "2001:db8::1 %s\n" , hostname); |
98 | xfclose (fp); |
99 | support_isolate_in_subprocess (callback: in_chroot, closure: chroot_dir); |
100 | } |
101 | free (ptr: path); |
102 | } |
103 | free (ptr: chroot_dir); |
104 | |
105 | return 0; |
106 | } |
107 | |
108 | #include <support/test-driver.c> |
109 | |