1 /* Test that reloading is disabled after a chroot.
2    Copyright (C) 2020-2022 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 <nss.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <limits.h>
24 #include <sys/types.h>
25 #include <errno.h>
26 #include <pwd.h>
27 #include <grp.h>
28 #include <unistd.h>
29 #include <netdb.h>
30 
31 #include <support/support.h>
32 #include <support/check.h>
33 #include <support/xunistd.h>
34 
35 #include "nss_test.h"
36 
37 #ifndef PATH_MAX
38 # define PATH_MAX 1024
39 #endif
40 
41 static struct passwd pwd_table1[] =
42   {
43    PWD_N (1234, "test1"),
44    PWD_N (4321, "test2"),
45    PWD_LAST ()
46   };
47 
48 static const char *group_4[] = {
49   "alpha", "beta", "gamma", "fred", NULL
50 };
51 
52 static struct group group_table_data1[] =
53   {
54    GRP (4),
55    GRP_LAST ()
56   };
57 
58 void
_nss_test1_init_hook(test_tables * t)59 _nss_test1_init_hook (test_tables *t)
60 {
61   t->pwd_table = pwd_table1;
62   t->grp_table = group_table_data1;
63 }
64 
65 static struct passwd pwd_table2[] =
66   {
67    PWD_N (5, "test1"),
68    PWD_N (2468, "test2"),
69    PWD_LAST ()
70   };
71 
72 static const char *group_5[] = {
73   "fred", NULL
74 };
75 
76 static struct group group_table_data2[] =
77   {
78    GRP (5),
79    GRP_LAST ()
80   };
81 
82 void
_nss_test2_init_hook(test_tables * t)83 _nss_test2_init_hook (test_tables *t)
84 {
85   t->pwd_table = pwd_table2;
86   t->grp_table = group_table_data2;
87 }
88 
89 static int
do_test(void)90 do_test (void)
91 {
92   struct passwd *pw;
93   struct group *gr;
94   struct hostent *he;
95   char buf1[PATH_MAX];
96   char buf2[PATH_MAX];
97 
98   support_need_proc ("Our xmkdirp fails if we can't map our uid, which requires /proc.");
99 
100   sprintf (buf1, "/subdir%s", support_slibdir_prefix);
101   xmkdirp (buf1, 0777);
102 
103   /* Copy this DSO into the chroot so it *could* be loaded.  */
104   sprintf (buf1, "%s/libnss_files.so.2", support_slibdir_prefix);
105   sprintf (buf2, "/subdir%s/libnss_files.so.2", support_slibdir_prefix);
106   support_copy_file (buf1, buf2);
107 
108   /* Check we're using the "outer" nsswitch.conf.  */
109 
110   /* This uses the test1 DSO.  */
111   pw = getpwnam ("test1");
112   TEST_VERIFY (pw != NULL);
113   if (pw)
114     TEST_COMPARE (pw->pw_uid, 1234);
115 
116   /* This just loads the test2 DSO.  */
117   gr = getgrgid (5);
118   TEST_VERIFY (gr != NULL);
119 
120 
121   /* Change the root dir.  */
122 
123   TEST_VERIFY (chroot ("/subdir") == 0);
124   chdir ("/");
125 
126   /* Check we're NOT using the "inner" nsswitch.conf.  */
127 
128   /* Both DSOs are loaded, which is used?  */
129   pw = getpwnam ("test2");
130   TEST_VERIFY (pw != NULL);
131   if (pw)
132     TEST_VERIFY (pw->pw_uid != 2468);
133 
134   /* We should still be using the old configuration.  */
135   pw = getpwnam ("test1");
136   TEST_VERIFY (pw != NULL);
137   if (pw)
138     TEST_COMPARE (pw->pw_uid, 1234);
139   gr = getgrgid (5);
140   TEST_VERIFY (gr != NULL);
141   gr = getgrnam ("name4");
142   TEST_VERIFY (gr == NULL);
143 
144   /* hosts in the outer nsswitch is files; the inner one is test1.
145      Verify that we're still using the outer nsswitch *and* that we
146      can load the files DSO. */
147   he = gethostbyname ("test2");
148   TEST_VERIFY (he != NULL);
149 
150   return 0;
151 }
152 
153 #include <support/test-driver.c>
154