1/* Check the usability of <dlfcn.h> functions in audit modules. Audit module.
2 Copyright (C) 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 <dlfcn.h>
20#include <first-versions.h>
21#include <gnu/lib-names.h>
22#include <link.h>
23#include <stdio.h>
24#include <string.h>
25#include <unistd.h>
26
27#include <support/check.h>
28#include <support/xdlfcn.h>
29
30unsigned int
31la_version (unsigned int current)
32{
33 /* Exercise various <dlfcn.h> functions. */
34
35 /* Check dlopen, dlsym, dlclose. */
36 void *handle = xdlopen (LIBM_SO, RTLD_LOCAL | RTLD_NOW);
37 void *ptr = xdlsym (handle, symbol: "sincos");
38 TEST_VERIFY (ptr != NULL);
39 ptr = dlsym (handle: handle, name: "SINCOS");
40 TEST_VERIFY (ptr == NULL);
41 const char *message = dlerror ();
42 TEST_VERIFY (strstr (message, ": undefined symbol: SINCOS") != NULL);
43 ptr = dlsym (handle: handle, name: "SINCOS");
44 TEST_VERIFY (ptr == NULL);
45 xdlclose (handle);
46 TEST_COMPARE_STRING (dlerror (), NULL);
47
48 handle = xdlopen (LIBC_SO, RTLD_LOCAL | RTLD_NOW | RTLD_NOLOAD);
49
50 /* Check dlvsym. _exit is unlikely to gain another symbol
51 version. */
52 TEST_VERIFY (xdlsym (handle, "_exit")
53 == xdlvsym (handle, "_exit", FIRST_VERSION_libc__exit_STRING));
54
55 /* Check dlinfo. */
56 {
57 void *handle2 = NULL;
58 TEST_COMPARE (dlinfo (handle, RTLD_DI_LINKMAP, &handle2), 0);
59 TEST_VERIFY (handle2 == handle);
60 }
61
62 /* Check dladdr and dladdr1. */
63 Dl_info info = { };
64 TEST_VERIFY (dladdr (&_exit, &info) != 0);
65 if (strcmp (s1: info.dli_sname, s2: "_Exit") != 0) /* _Exit is an alias. */
66 TEST_COMPARE_STRING (info.dli_sname, "_exit");
67 TEST_VERIFY (info.dli_saddr == &_exit);
68 TEST_VERIFY (strstr (info.dli_fname, LIBC_SO));
69 void *extra_info;
70 memset (s: &info, c: 0, n: sizeof (info));
71 TEST_VERIFY (dladdr1 (&_exit, &info, &extra_info, RTLD_DL_LINKMAP) != 0);
72 TEST_VERIFY (extra_info == handle);
73
74 /* Check _dl_find_object. */
75 struct dl_find_object dlfo;
76 TEST_COMPARE (_dl_find_object (__builtin_return_address (0), &dlfo), 0);
77 /* "ld.so" is seen with --enable-hardcoded-path-in-tests. */
78 if (strcmp (s1: basename (filename: dlfo.dlfo_link_map->l_name), s2: "ld.so") != 0)
79 TEST_COMPARE_STRING (basename (dlfo.dlfo_link_map->l_name), LD_SO);
80 TEST_COMPARE (_dl_find_object (dlsym (handle, "environ"), &dlfo), 0);
81 TEST_COMPARE_STRING (basename (dlfo.dlfo_link_map->l_name), LIBC_SO);
82 TEST_COMPARE (_dl_find_object ((void *) 1, &dlfo), -1);
83 TEST_COMPARE (_dl_find_object ((void *) -1, &dlfo), -1);
84
85 /* Verify that dlmopen creates a new namespace. */
86 void *dlmopen_handle = xdlmopen (LM_ID_NEWLM, LIBC_SO, RTLD_NOW);
87 TEST_VERIFY (dlmopen_handle != handle);
88 memset (s: &info, c: 0, n: sizeof (info));
89 extra_info = NULL;
90 ptr = xdlsym (handle: dlmopen_handle, symbol: "_exit");
91 TEST_VERIFY (dladdr1 (ptr, &info, &extra_info, RTLD_DL_LINKMAP) != 0);
92 TEST_VERIFY (extra_info == dlmopen_handle);
93 xdlclose (handle: dlmopen_handle);
94
95 /* Terminate the process with an error state. This does not happen
96 automatically because the audit module state is not shared with
97 the main program. */
98 if (support_record_failure_is_failed ())
99 {
100 fflush (stdout);
101 fflush (stderr);
102 _exit (status: 1);
103 }
104
105 return LAV_CURRENT;
106}
107
108char *
109la_objsearch (const char *name, uintptr_t *cookie, unsigned int flag)
110{
111 if (strcmp (s1: name, s2: "mapped to libc") == 0)
112 return (char *) LIBC_SO;
113 else
114 return (char *) name;
115}
116

source code of glibc/elf/tst-auditmod26.c