1 /* Load a shared object at run time.
2 Copyright (C) 1995-2022 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 <errno.h>
21 #include <libintl.h>
22 #include <stddef.h>
23 #include <unistd.h>
24 #include <ldsodefs.h>
25 #include <shlib-compat.h>
26
27 struct dlmopen_args
28 {
29 /* Namespace ID. */
30 Lmid_t nsid;
31 /* The arguments for dlopen_doit. */
32 const char *file;
33 int mode;
34 /* The return value of dlopen_doit. */
35 void *new;
36 /* Address of the caller. */
37 const void *caller;
38 };
39
40 static void
dlmopen_doit(void * a)41 dlmopen_doit (void *a)
42 {
43 struct dlmopen_args *args = (struct dlmopen_args *) a;
44
45 /* Non-shared code has no support for multiple namespaces. */
46 if (args->nsid != LM_ID_BASE)
47 {
48 # ifdef SHARED
49 /* If trying to open the link map for the main executable the namespace
50 must be the main one. */
51 if (args->file == NULL)
52 # endif
53 _dl_signal_error (EINVAL, NULL, NULL, N_("invalid namespace"));
54
55 /* It makes no sense to use RTLD_GLOBAL when loading a DSO into
56 a namespace other than the base namespace. */
57 if (__glibc_unlikely (args->mode & RTLD_GLOBAL))
58 _dl_signal_error (EINVAL, NULL, NULL, N_("invalid mode"));
59 }
60
61 args->new = GLRO(dl_open) (args->file ?: "", args->mode | __RTLD_DLOPEN,
62 args->caller,
63 args->nsid, __libc_argc, __libc_argv, __environ);
64 }
65
66 static void *
dlmopen_implementation(Lmid_t nsid,const char * file,int mode,void * dl_caller)67 dlmopen_implementation (Lmid_t nsid, const char *file, int mode,
68 void *dl_caller)
69 {
70 struct dlmopen_args args;
71 args.nsid = nsid;
72 args.file = file;
73 args.mode = mode;
74 args.caller = dl_caller;
75
76 return _dlerror_run (dlmopen_doit, &args) ? NULL : args.new;
77 }
78
79 #ifdef SHARED
80 void *
___dlmopen(Lmid_t nsid,const char * file,int mode)81 ___dlmopen (Lmid_t nsid, const char *file, int mode)
82 {
83 if (GLRO (dl_dlfcn_hook) != NULL)
84 return GLRO (dl_dlfcn_hook)->dlmopen (nsid, file, mode, RETURN_ADDRESS (0));
85 else
86 return dlmopen_implementation (nsid, file, mode, RETURN_ADDRESS (0));
87 }
88 versioned_symbol (libc, ___dlmopen, dlmopen, GLIBC_2_34);
89
90 # if OTHER_SHLIB_COMPAT (libdl, GLIBC_2_3_4, GLIBC_2_34)
91 compat_symbol (libdl, ___dlmopen, dlmopen, GLIBC_2_3_4);
92 # endif
93 #else /* !SHARED */
94 /* Also used with _dlfcn_hook. */
95 void *
__dlmopen(Lmid_t nsid,const char * file,int mode,void * dl_caller)96 __dlmopen (Lmid_t nsid, const char *file, int mode, void *dl_caller)
97 {
98 return dlmopen_implementation (nsid, file, mode, RETURN_ADDRESS (0));
99 }
100
101 void *
___dlmopen(Lmid_t nsid,const char * file,int mode)102 ___dlmopen (Lmid_t nsid, const char *file, int mode)
103 {
104 return __dlmopen (nsid, file, mode, RETURN_ADDRESS (0));
105 }
106 weak_alias (___dlmopen, dlmopen)
107 static_link_warning (dlmopen)
108 #endif /* !SHARED */
109