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Commit | Line | Data |
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d66e34cd | 1 | /* Run time dynamic linker. |
49891c10 | 2 | Copyright (C) 1995, 1996, 1997, 1998 Free Software Foundation, Inc. |
afd4eb37 | 3 | This file is part of the GNU C Library. |
d66e34cd | 4 | |
afd4eb37 UD |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Library General Public License as | |
7 | published by the Free Software Foundation; either version 2 of the | |
8 | License, or (at your option) any later version. | |
d66e34cd | 9 | |
afd4eb37 UD |
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 | Library General Public License for more details. | |
d66e34cd | 14 | |
afd4eb37 UD |
15 | You should have received a copy of the GNU Library General Public |
16 | License along with the GNU C Library; see the file COPYING.LIB. If not, | |
17 | write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
18 | Boston, MA 02111-1307, USA. */ | |
d66e34cd | 19 | |
7dea968e | 20 | #include <fcntl.h> |
d66e34cd | 21 | #include <stdlib.h> |
f51d1dfd | 22 | #include <string.h> |
d66e34cd | 23 | #include <unistd.h> |
2064087b | 24 | #include <sys/mman.h> /* Check if MAP_ANON is defined. */ |
a853022c | 25 | #include <elf/ldsodefs.h> |
ce37fa88 | 26 | #include <stdio-common/_itoa.h> |
f21acc89 | 27 | #include <entry.h> |
f5348425 | 28 | #include "dynamic-link.h" |
e2102c14 | 29 | #include "dl-librecon.h" |
f5348425 | 30 | |
a853022c | 31 | #include <assert.h> |
f5348425 | 32 | |
d66e34cd RM |
33 | /* System-specific function to do initial startup for the dynamic linker. |
34 | After this, file access calls and getenv must work. This is responsible | |
cddcfecf | 35 | for setting __libc_enable_secure if we need to be secure (e.g. setuid), |
d66e34cd | 36 | and for setting _dl_argc and _dl_argv, and then calling _dl_main. */ |
266180eb RM |
37 | extern ElfW(Addr) _dl_sysdep_start (void **start_argptr, |
38 | void (*dl_main) (const ElfW(Phdr) *phdr, | |
39 | ElfW(Half) phent, | |
40 | ElfW(Addr) *user_entry)); | |
4cb20290 | 41 | extern void _dl_sysdep_start_cleanup (void); |
d66e34cd | 42 | |
14bab8de UD |
43 | /* System-dependent function to read a file's whole contents |
44 | in the most convenient manner available. */ | |
45 | extern void *_dl_sysdep_read_whole_file (const char *filename, | |
46 | size_t *filesize_ptr, | |
47 | int mmap_prot); | |
48 | ||
fd26970f | 49 | /* Helper function to handle errors while resolving symbols. */ |
c84142e8 UD |
50 | static void print_unresolved (int errcode, const char *objname, |
51 | const char *errsting); | |
52 | ||
53 | /* Helper function to handle errors when a version is missing. */ | |
54 | static void print_missing_version (int errcode, const char *objname, | |
55 | const char *errsting); | |
fd26970f | 56 | |
ea278354 UD |
57 | |
58 | /* This is a list of all the modes the dynamic loader can be in. */ | |
59 | enum mode { normal, list, verify, trace }; | |
60 | ||
61 | /* Process all environments variables the dynamic linker must recognize. | |
62 | Since all of them start with `LD_' we are a bit smarter while finding | |
63 | all the entries. */ | |
64 | static void process_envvars (enum mode *modep, int *lazyp); | |
65 | ||
d66e34cd RM |
66 | int _dl_argc; |
67 | char **_dl_argv; | |
4cb20290 | 68 | const char *_dl_rpath; |
cf29ffbe | 69 | int _dl_verbose; |
0a54e401 UD |
70 | const char *_dl_platform; |
71 | size_t _dl_platformlen; | |
f41c8091 | 72 | unsigned long _dl_hwcap; |
0a54e401 | 73 | struct r_search_path *_dl_search_paths; |
3996f34b UD |
74 | const char *_dl_profile; |
75 | const char *_dl_profile_output; | |
76 | struct link_map *_dl_profile_map; | |
b5efde2f | 77 | int _dl_debug_libs; |
7dea968e | 78 | int _dl_debug_impcalls; |
0c367d92 | 79 | int _dl_debug_bindings; |
de100ca7 | 80 | int _dl_debug_symbols; |
8193034b UD |
81 | int _dl_debug_versions; |
82 | int _dl_debug_reloc; | |
83 | int _dl_debug_files; | |
d66e34cd | 84 | |
39778c6c UD |
85 | /* Set nonzero during loading and initialization of executable and |
86 | libraries, cleared before the executable's entry point runs. This | |
87 | must not be initialized to nonzero, because the unused dynamic | |
88 | linker loaded in for libc.so's "ld.so.1" dep will provide the | |
89 | definition seen by libc.so's initializer; that value must be zero, | |
90 | and will be since that dynamic linker's _dl_start and dl_main will | |
91 | never be called. */ | |
92 | int _dl_starting_up; | |
93 | ||
266180eb RM |
94 | static void dl_main (const ElfW(Phdr) *phdr, |
95 | ElfW(Half) phent, | |
96 | ElfW(Addr) *user_entry); | |
d66e34cd | 97 | |
ee188d55 | 98 | struct link_map _dl_rtld_map; |
c84142e8 | 99 | struct libname_list _dl_rtld_libname; |
f41c8091 | 100 | struct libname_list _dl_rtld_libname2; |
86d2c878 | 101 | |
b1dbbaa4 RM |
102 | #ifdef RTLD_START |
103 | RTLD_START | |
104 | #else | |
105 | #error "sysdeps/MACHINE/dl-machine.h fails to define RTLD_START" | |
106 | #endif | |
107 | ||
ceb2d9aa | 108 | static ElfW(Addr) |
d66e34cd RM |
109 | _dl_start (void *arg) |
110 | { | |
86d2c878 | 111 | struct link_map bootstrap_map; |
d66e34cd | 112 | |
b1dbbaa4 RM |
113 | /* This #define produces dynamic linking inline functions for |
114 | bootstrap relocation instead of general-purpose relocation. */ | |
115 | #define RTLD_BOOTSTRAP | |
c84142e8 | 116 | #define RESOLVE(sym, version, flags) bootstrap_map.l_addr |
b1dbbaa4 RM |
117 | #include "dynamic-link.h" |
118 | ||
d66e34cd | 119 | /* Figure out the run-time load address of the dynamic linker itself. */ |
86d2c878 | 120 | bootstrap_map.l_addr = elf_machine_load_address (); |
d66e34cd | 121 | |
47707456 UD |
122 | /* Read our own dynamic section and fill in the info array. */ |
123 | bootstrap_map.l_ld = (void *) bootstrap_map.l_addr + elf_machine_dynamic (); | |
86d2c878 | 124 | elf_get_dynamic_info (bootstrap_map.l_ld, bootstrap_map.l_info); |
d66e34cd RM |
125 | |
126 | #ifdef ELF_MACHINE_BEFORE_RTLD_RELOC | |
86d2c878 | 127 | ELF_MACHINE_BEFORE_RTLD_RELOC (bootstrap_map.l_info); |
d66e34cd RM |
128 | #endif |
129 | ||
130 | /* Relocate ourselves so we can do normal function calls and | |
131 | data access using the global offset table. */ | |
421f82e5 | 132 | |
3996f34b | 133 | ELF_DYNAMIC_RELOCATE (&bootstrap_map, 0, 0); |
ea7eb7e3 UD |
134 | /* Please note that we don't allow profiling of this object and |
135 | therefore need not test whether we have to allocate the array | |
136 | for the relocation results (as done in dl-reloc.c). */ | |
421f82e5 | 137 | |
d66e34cd RM |
138 | /* Now life is sane; we can call functions and access global data. |
139 | Set up to use the operating system facilities, and find out from | |
140 | the operating system's program loader where to find the program | |
141 | header table in core. */ | |
142 | ||
86d2c878 | 143 | /* Transfer data about ourselves to the permanent link_map structure. */ |
ee188d55 RM |
144 | _dl_rtld_map.l_addr = bootstrap_map.l_addr; |
145 | _dl_rtld_map.l_ld = bootstrap_map.l_ld; | |
f41c8091 | 146 | _dl_rtld_map.l_opencount = 1; |
ee188d55 RM |
147 | memcpy (_dl_rtld_map.l_info, bootstrap_map.l_info, |
148 | sizeof _dl_rtld_map.l_info); | |
149 | _dl_setup_hash (&_dl_rtld_map); | |
86d2c878 | 150 | |
4cb20290 RM |
151 | /* Cache the DT_RPATH stored in ld.so itself; this will be |
152 | the default search path. */ | |
f41c8091 UD |
153 | if (_dl_rtld_map.l_info[DT_STRTAB] && _dl_rtld_map.l_info[DT_RPATH]) |
154 | { | |
155 | _dl_rpath = (void *) (_dl_rtld_map.l_addr + | |
156 | _dl_rtld_map.l_info[DT_STRTAB]->d_un.d_ptr + | |
157 | _dl_rtld_map.l_info[DT_RPATH]->d_un.d_val); | |
158 | } | |
d66e34cd RM |
159 | |
160 | /* Call the OS-dependent function to set up life so we can do things like | |
161 | file access. It will call `dl_main' (below) to do all the real work | |
162 | of the dynamic linker, and then unwind our frame and run the user | |
163 | entry point on the same stack we entered on. */ | |
8d6468d0 | 164 | return _dl_sysdep_start (arg, &dl_main); |
d66e34cd RM |
165 | } |
166 | ||
d66e34cd RM |
167 | /* Now life is peachy; we can do all normal operations. |
168 | On to the real work. */ | |
169 | ||
f21acc89 | 170 | void ENTRY_POINT (void); |
d66e34cd | 171 | |
993b3242 UD |
172 | /* Some helper functions. */ |
173 | ||
174 | /* Arguments to relocate_doit. */ | |
175 | struct relocate_args | |
176 | { | |
177 | struct link_map *l; | |
178 | int lazy; | |
179 | }; | |
180 | ||
181 | struct map_args | |
182 | { | |
183 | /* Argument to map_doit. */ | |
184 | char *str; | |
185 | /* Return value of map_doit. */ | |
186 | struct link_map *main_map; | |
187 | }; | |
188 | ||
189 | /* Arguments to version_check_doit. */ | |
190 | struct version_check_args | |
191 | { | |
192 | struct link_map *main_map; | |
193 | int doexit; | |
194 | }; | |
195 | ||
196 | static void | |
197 | relocate_doit (void *a) | |
198 | { | |
199 | struct relocate_args *args = (struct relocate_args *) a; | |
200 | ||
201 | _dl_relocate_object (args->l, _dl_object_relocation_scope (args->l), | |
202 | args->lazy); | |
203 | } | |
204 | ||
205 | static void | |
206 | map_doit (void *a) | |
207 | { | |
208 | struct map_args *args = (struct map_args *)a; | |
c6222ab9 | 209 | args->main_map = _dl_map_object (NULL, args->str, 0, lt_library, 0); |
993b3242 UD |
210 | } |
211 | ||
212 | static void | |
213 | version_check_doit (void *a) | |
214 | { | |
215 | struct version_check_args *args = (struct version_check_args *)a; | |
216 | if (_dl_check_all_versions (args->main_map, 1) && args->doexit) | |
217 | /* We cannot start the application. Abort now. */ | |
218 | _exit (1); | |
219 | } | |
220 | ||
ce37fa88 UD |
221 | |
222 | static inline struct link_map * | |
223 | find_needed (const char *name) | |
224 | { | |
225 | unsigned int n; | |
226 | ||
227 | for (n = 0; n < _dl_loaded->l_nsearchlist; ++n) | |
228 | if (_dl_name_match_p (name, _dl_loaded->l_searchlist[n])) | |
229 | return _dl_loaded->l_searchlist[n]; | |
230 | ||
231 | /* Should never happen. */ | |
232 | return NULL; | |
233 | } | |
234 | ||
235 | static int | |
236 | match_version (const char *string, struct link_map *map) | |
237 | { | |
238 | const char *strtab = (const char *) (map->l_addr | |
239 | + map->l_info[DT_STRTAB]->d_un.d_ptr); | |
240 | ElfW(Verdef) *def; | |
241 | ||
242 | #define VERDEFTAG (DT_NUM + DT_PROCNUM + DT_VERSIONTAGIDX (DT_VERDEF)) | |
243 | if (map->l_info[VERDEFTAG] == NULL) | |
244 | /* The file has no symbol versioning. */ | |
245 | return 0; | |
246 | ||
247 | def = (ElfW(Verdef) *) ((char *) map->l_addr | |
248 | + map->l_info[VERDEFTAG]->d_un.d_ptr); | |
249 | while (1) | |
250 | { | |
251 | ElfW(Verdaux) *aux = (ElfW(Verdaux) *) ((char *) def + def->vd_aux); | |
252 | ||
253 | /* Compare the version strings. */ | |
254 | if (strcmp (string, strtab + aux->vda_name) == 0) | |
255 | /* Bingo! */ | |
256 | return 1; | |
257 | ||
258 | /* If no more definitions we failed to find what we want. */ | |
259 | if (def->vd_next == 0) | |
260 | break; | |
261 | ||
262 | /* Next definition. */ | |
263 | def = (ElfW(Verdef) *) ((char *) def + def->vd_next); | |
264 | } | |
265 | ||
266 | return 0; | |
267 | } | |
268 | ||
120b4c49 UD |
269 | static unsigned int _dl_skip_args; /* Nonzero if we were run directly. */ |
270 | static const char *library_path; /* The library search path. */ | |
271 | static const char *preloadlist; /* The list preloaded objects. */ | |
272 | static int version_info; /* Nonzero if information about | |
273 | versions has to be printed. */ | |
a1a9d215 | 274 | |
d66e34cd | 275 | static void |
266180eb RM |
276 | dl_main (const ElfW(Phdr) *phdr, |
277 | ElfW(Half) phent, | |
278 | ElfW(Addr) *user_entry) | |
d66e34cd | 279 | { |
266180eb | 280 | const ElfW(Phdr) *ph; |
ceb2d9aa | 281 | struct link_map *main_map; |
0200214b | 282 | int lazy; |
ea278354 | 283 | enum mode mode; |
2064087b RM |
284 | struct link_map **preloads; |
285 | unsigned int npreloads; | |
14bab8de UD |
286 | size_t file_size; |
287 | char *file; | |
2f6d1f1b | 288 | int has_interp = 0; |
77aba05b | 289 | unsigned int i; |
d66e34cd | 290 | |
ea278354 UD |
291 | /* Process the environment variable which control the behaviour. */ |
292 | process_envvars (&mode, &lazy); | |
3996f34b | 293 | |
46ec036d UD |
294 | /* Set up a flag which tells we are just starting. */ |
295 | _dl_starting_up = 1; | |
296 | ||
f21acc89 | 297 | if (*user_entry == (ElfW(Addr)) &ENTRY_POINT) |
0200214b RM |
298 | { |
299 | /* Ho ho. We are not the program interpreter! We are the program | |
300 | itself! This means someone ran ld.so as a command. Well, that | |
301 | might be convenient to do sometimes. We support it by | |
302 | interpreting the args like this: | |
303 | ||
304 | ld.so PROGRAM ARGS... | |
305 | ||
306 | The first argument is the name of a file containing an ELF | |
307 | executable we will load and run with the following arguments. | |
308 | To simplify life here, PROGRAM is searched for using the | |
309 | normal rules for shared objects, rather than $PATH or anything | |
310 | like that. We just load it and use its entry point; we don't | |
311 | pay attention to its PT_INTERP command (we are the interpreter | |
312 | ourselves). This is an easy way to test a new ld.so before | |
313 | installing it. */ | |
421f82e5 | 314 | |
ffee1316 RM |
315 | /* Note the place where the dynamic linker actually came from. */ |
316 | _dl_rtld_map.l_name = _dl_argv[0]; | |
6a76c115 | 317 | |
fd26970f UD |
318 | while (_dl_argc > 1) |
319 | if (! strcmp (_dl_argv[1], "--list")) | |
320 | { | |
321 | mode = list; | |
322 | lazy = -1; /* This means do no dependency analysis. */ | |
61965e9b | 323 | |
fd26970f UD |
324 | ++_dl_skip_args; |
325 | --_dl_argc; | |
326 | ++_dl_argv; | |
327 | } | |
328 | else if (! strcmp (_dl_argv[1], "--verify")) | |
329 | { | |
330 | mode = verify; | |
6a76c115 | 331 | |
fd26970f UD |
332 | ++_dl_skip_args; |
333 | --_dl_argc; | |
334 | ++_dl_argv; | |
335 | } | |
880f421f UD |
336 | else if (! strcmp (_dl_argv[1], "--library-path") |
337 | && _dl_argc > 2) | |
338 | { | |
339 | library_path = _dl_argv[2]; | |
340 | ||
341 | _dl_skip_args += 2; | |
342 | _dl_argc -= 2; | |
343 | _dl_argv += 2; | |
344 | } | |
fd26970f UD |
345 | else |
346 | break; | |
d66e34cd | 347 | |
61eb22d3 UD |
348 | /* If we have no further argument the program was called incorrectly. |
349 | Grant the user some education. */ | |
350 | if (_dl_argc < 2) | |
351 | _dl_sysdep_fatal ("\ | |
2bcf29ba | 352 | Usage: ld.so [OPTION]... EXECUTABLE-FILE [ARGS-FOR-PROGRAM...]\n\ |
61eb22d3 UD |
353 | You have invoked `ld.so', the helper program for shared library executables.\n\ |
354 | This program usually lives in the file `/lib/ld.so', and special directives\n\ | |
355 | in executable files using ELF shared libraries tell the system's program\n\ | |
356 | loader to load the helper program from this file. This helper program loads\n\ | |
357 | the shared libraries needed by the program executable, prepares the program\n\ | |
358 | to run, and runs it. You may invoke this helper program directly from the\n\ | |
359 | command line to load and run an ELF executable file; this is like executing\n\ | |
360 | that file itself, but always uses this helper program from the file you\n\ | |
361 | specified, instead of the helper program file specified in the executable\n\ | |
362 | file you run. This is mostly of use for maintainers to test new versions\n\ | |
2bcf29ba UD |
363 | of this helper program; chances are you did not intend to run this program.\n\ |
364 | \n\ | |
365 | --list list all dependencies and how they are resolved\n\ | |
366 | --verify verify that given object really is a dynamically linked\n\ | |
367 | object we get handle\n\ | |
368 | --library-path PATH use given PATH instead of content of the environment\n\ | |
369 | variable LD_LIBRARY_PATH\n", | |
61eb22d3 UD |
370 | NULL); |
371 | ||
0200214b RM |
372 | ++_dl_skip_args; |
373 | --_dl_argc; | |
374 | ++_dl_argv; | |
91f62ce6 | 375 | |
da832465 UD |
376 | /* Initialize the data structures for the search paths for shared |
377 | objects. */ | |
378 | _dl_init_paths (library_path); | |
379 | ||
2de99474 UD |
380 | if (mode == verify) |
381 | { | |
dcf0671d | 382 | char *err_str = NULL; |
993b3242 | 383 | struct map_args args; |
2de99474 | 384 | |
993b3242 | 385 | args.str = _dl_argv[0]; |
8d9618b7 | 386 | (void) _dl_catch_error (&err_str, map_doit, &args); |
993b3242 | 387 | main_map = args.main_map; |
2de99474 | 388 | if (err_str != NULL) |
dcf0671d UD |
389 | { |
390 | free (err_str); | |
391 | _exit (EXIT_FAILURE); | |
392 | } | |
2de99474 UD |
393 | } |
394 | else | |
c6222ab9 | 395 | main_map = _dl_map_object (NULL, _dl_argv[0], 0, lt_library, 0); |
2de99474 | 396 | |
ceb2d9aa UD |
397 | phdr = main_map->l_phdr; |
398 | phent = main_map->l_phnum; | |
399 | main_map->l_name = (char *) ""; | |
400 | *user_entry = main_map->l_entry; | |
0200214b RM |
401 | } |
402 | else | |
403 | { | |
404 | /* Create a link_map for the executable itself. | |
405 | This will be what dlopen on "" returns. */ | |
1618c590 | 406 | main_map = _dl_new_object ((char *) "", "", lt_executable); |
ceb2d9aa | 407 | if (main_map == NULL) |
762a2918 | 408 | _dl_sysdep_fatal ("cannot allocate memory for link map\n", NULL); |
ceb2d9aa UD |
409 | main_map->l_phdr = phdr; |
410 | main_map->l_phnum = phent; | |
411 | main_map->l_entry = *user_entry; | |
3e5f5557 | 412 | main_map->l_opencount = 1; |
da832465 | 413 | |
97a51d8a UD |
414 | /* We delay initializing the path structure until we got the dynamic |
415 | information for the program. */ | |
0200214b RM |
416 | } |
417 | ||
418 | /* Scan the program header table for the dynamic section. */ | |
419 | for (ph = phdr; ph < &phdr[phent]; ++ph) | |
420 | switch (ph->p_type) | |
421 | { | |
da832465 UD |
422 | case PT_PHDR: |
423 | /* Find out the load address. */ | |
424 | main_map->l_addr = (ElfW(Addr)) phdr - ph->p_vaddr; | |
425 | break; | |
0200214b RM |
426 | case PT_DYNAMIC: |
427 | /* This tells us where to find the dynamic section, | |
428 | which tells us everything we need to do. */ | |
ceb2d9aa | 429 | main_map->l_ld = (void *) main_map->l_addr + ph->p_vaddr; |
0200214b RM |
430 | break; |
431 | case PT_INTERP: | |
432 | /* This "interpreter segment" was used by the program loader to | |
433 | find the program interpreter, which is this program itself, the | |
434 | dynamic linker. We note what name finds us, so that a future | |
435 | dlopen call or DT_NEEDED entry, for something that wants to link | |
436 | against the dynamic linker as a shared library, will know that | |
437 | the shared object is already loaded. */ | |
ceb2d9aa | 438 | _dl_rtld_libname.name = (const char *) main_map->l_addr + ph->p_vaddr; |
c84142e8 UD |
439 | _dl_rtld_libname.next = NULL; |
440 | _dl_rtld_map.l_libname = &_dl_rtld_libname; | |
f41c8091 UD |
441 | |
442 | /* Ordinarilly, we would get additional names for the loader from | |
443 | our DT_SONAME. This can't happen if we were actually linked as | |
444 | a static executable (detect this case when we have no DYNAMIC). | |
445 | If so, assume the filename component of the interpreter path to | |
446 | be our SONAME, and add it to our name list. */ | |
447 | if (_dl_rtld_map.l_ld == NULL) | |
448 | { | |
449 | char *p = strrchr (_dl_rtld_libname.name, '/'); | |
450 | if (p) | |
451 | { | |
452 | _dl_rtld_libname2.name = p+1; | |
453 | _dl_rtld_libname2.next = NULL; | |
454 | _dl_rtld_libname.next = &_dl_rtld_libname2; | |
455 | } | |
456 | } | |
457 | ||
2f6d1f1b | 458 | has_interp = 1; |
0200214b RM |
459 | break; |
460 | } | |
ffee1316 | 461 | if (! _dl_rtld_map.l_libname && _dl_rtld_map.l_name) |
c84142e8 UD |
462 | { |
463 | /* We were invoked directly, so the program might not have a | |
464 | PT_INTERP. */ | |
465 | _dl_rtld_libname.name = _dl_rtld_map.l_name; | |
466 | _dl_rtld_libname.next = NULL; | |
467 | _dl_rtld_map.l_libname = &_dl_rtld_libname; | |
468 | } | |
ffee1316 RM |
469 | else |
470 | assert (_dl_rtld_map.l_libname); /* How else did we get here? */ | |
0200214b RM |
471 | |
472 | /* Extract the contents of the dynamic section for easy access. */ | |
ceb2d9aa UD |
473 | elf_get_dynamic_info (main_map->l_ld, main_map->l_info); |
474 | if (main_map->l_info[DT_HASH]) | |
0200214b | 475 | /* Set up our cache of pointers into the hash table. */ |
ceb2d9aa | 476 | _dl_setup_hash (main_map); |
0200214b | 477 | |
e2102c14 UD |
478 | if (mode == verify) |
479 | { | |
480 | /* We were called just to verify that this is a dynamic | |
481 | executable using us as the program interpreter. Exit with an | |
482 | error if we were not able to load the binary or no interpreter | |
483 | is specified (i.e., this is no dynamically linked binary. */ | |
484 | if (main_map->l_ld == NULL) | |
485 | _exit (1); | |
486 | if (!has_interp) | |
487 | _exit (2); | |
488 | ||
489 | /* We allow here some platform specific code. */ | |
490 | #ifdef DISTINGUISH_LIB_VERSIONS | |
491 | DISTINGUISH_LIB_VERSIONS; | |
492 | #endif | |
493 | _exit (0); | |
494 | } | |
495 | ||
97a51d8a UD |
496 | if (*user_entry != (ElfW(Addr)) &ENTRY_POINT) |
497 | /* Initialize the data structures for the search paths for shared | |
498 | objects. */ | |
120b4c49 | 499 | _dl_init_paths (library_path); |
97a51d8a | 500 | |
0200214b | 501 | /* Put the link_map for ourselves on the chain so it can be found by |
ceb2d9aa UD |
502 | name. Note that at this point the global chain of link maps contains |
503 | exactly one element, which is pointed to by main_map. */ | |
ffee1316 RM |
504 | if (! _dl_rtld_map.l_name) |
505 | /* If not invoked directly, the dynamic linker shared object file was | |
506 | found by the PT_INTERP name. */ | |
c84142e8 | 507 | _dl_rtld_map.l_name = (char *) _dl_rtld_map.l_libname->name; |
ba79d61b | 508 | _dl_rtld_map.l_type = lt_library; |
ceb2d9aa UD |
509 | main_map->l_next = &_dl_rtld_map; |
510 | _dl_rtld_map.l_prev = main_map; | |
0200214b | 511 | |
14bab8de UD |
512 | /* We have two ways to specify objects to preload: via environment |
513 | variable and via the file /etc/ld.so.preload. The later can also | |
514 | be used when security is enabled. */ | |
2064087b RM |
515 | preloads = NULL; |
516 | npreloads = 0; | |
14bab8de | 517 | |
fd26970f | 518 | if (preloadlist) |
c4029823 | 519 | { |
566efee2 UD |
520 | /* The LD_PRELOAD environment variable gives list of libraries |
521 | separated by white space or colons that are loaded before the | |
fd26970f UD |
522 | executable's dependencies and prepended to the global scope |
523 | list. If the binary is running setuid all elements | |
524 | containing a '/' are ignored since it is insecure. */ | |
525 | char *list = strdupa (preloadlist); | |
526 | char *p; | |
566efee2 | 527 | while ((p = strsep (&list, " :")) != NULL) |
e2102c14 UD |
528 | if (p[0] != '\0' |
529 | && (! __libc_enable_secure || strchr (p, '/') == NULL)) | |
fd26970f | 530 | { |
2bcf29ba | 531 | struct link_map *new_map = _dl_map_object (main_map, p, 1, |
c6222ab9 | 532 | lt_library, 0); |
bd355af0 UD |
533 | if (new_map->l_opencount == 1) |
534 | /* It is no duplicate. */ | |
535 | ++npreloads; | |
fd26970f | 536 | } |
c4029823 UD |
537 | } |
538 | ||
14bab8de UD |
539 | /* Read the contents of the file. */ |
540 | file = _dl_sysdep_read_whole_file ("/etc/ld.so.preload", &file_size, | |
541 | PROT_READ | PROT_WRITE); | |
542 | if (file) | |
543 | { | |
544 | /* Parse the file. It contains names of libraries to be loaded, | |
545 | separated by white spaces or `:'. It may also contain | |
546 | comments introduced by `#'. */ | |
547 | char *problem; | |
548 | char *runp; | |
549 | size_t rest; | |
550 | ||
551 | /* Eliminate comments. */ | |
552 | runp = file; | |
553 | rest = file_size; | |
554 | while (rest > 0) | |
555 | { | |
556 | char *comment = memchr (runp, '#', rest); | |
557 | if (comment == NULL) | |
558 | break; | |
559 | ||
560 | rest -= comment - runp; | |
561 | do | |
562 | *comment = ' '; | |
563 | while (--rest > 0 && *++comment != '\n'); | |
564 | } | |
565 | ||
566 | /* We have one problematic case: if we have a name at the end of | |
567 | the file without a trailing terminating characters, we cannot | |
568 | place the \0. Handle the case separately. */ | |
49891c10 UD |
569 | if (file[file_size - 1] != ' ' && file[file_size - 1] != '\t' |
570 | && file[file_size - 1] != '\n' && file[file_size - 1] != ':') | |
14bab8de UD |
571 | { |
572 | problem = &file[file_size]; | |
573 | while (problem > file && problem[-1] != ' ' && problem[-1] != '\t' | |
49891c10 | 574 | && problem[-1] != '\n' && problem[-1] != ':') |
14bab8de UD |
575 | --problem; |
576 | ||
577 | if (problem > file) | |
578 | problem[-1] = '\0'; | |
579 | } | |
580 | else | |
49891c10 UD |
581 | { |
582 | problem = NULL; | |
583 | file[file_size - 1] = '\0'; | |
584 | } | |
14bab8de UD |
585 | |
586 | if (file != problem) | |
587 | { | |
588 | char *p; | |
e2102c14 | 589 | runp = file; |
14bab8de | 590 | while ((p = strsep (&runp, ": \t\n")) != NULL) |
e2102c14 UD |
591 | if (p[0] != '\0') |
592 | { | |
593 | struct link_map *new_map = _dl_map_object (main_map, p, 1, | |
594 | lt_library, 0); | |
595 | if (new_map->l_opencount == 1) | |
596 | /* It is no duplicate. */ | |
597 | ++npreloads; | |
598 | } | |
14bab8de UD |
599 | } |
600 | ||
601 | if (problem != NULL) | |
602 | { | |
603 | char *p = strndupa (problem, file_size - (problem - file)); | |
2bcf29ba | 604 | struct link_map *new_map = _dl_map_object (main_map, p, 1, |
c6222ab9 | 605 | lt_library, 0); |
bd355af0 UD |
606 | if (new_map->l_opencount == 1) |
607 | /* It is no duplicate. */ | |
608 | ++npreloads; | |
14bab8de UD |
609 | } |
610 | ||
611 | /* We don't need the file anymore. */ | |
612 | __munmap (file, file_size); | |
613 | } | |
614 | ||
14bab8de UD |
615 | if (npreloads != 0) |
616 | { | |
617 | /* Set up PRELOADS with a vector of the preloaded libraries. */ | |
618 | struct link_map *l; | |
14bab8de UD |
619 | preloads = __alloca (npreloads * sizeof preloads[0]); |
620 | l = _dl_rtld_map.l_next; /* End of the chain before preloads. */ | |
621 | i = 0; | |
622 | do | |
623 | { | |
624 | preloads[i++] = l; | |
625 | l = l->l_next; | |
626 | } while (l); | |
627 | assert (i == npreloads); | |
628 | } | |
629 | ||
2064087b RM |
630 | /* Load all the libraries specified by DT_NEEDED entries. If LD_PRELOAD |
631 | specified some libraries to load, these are inserted before the actual | |
632 | dependencies in the executable's searchlist for symbol resolution. */ | |
ceb2d9aa | 633 | _dl_map_object_deps (main_map, preloads, npreloads, mode == trace); |
d66e34cd | 634 | |
2064087b | 635 | #ifndef MAP_ANON |
f332db02 RM |
636 | /* We are done mapping things, so close the zero-fill descriptor. */ |
637 | __close (_dl_zerofd); | |
638 | _dl_zerofd = -1; | |
2064087b | 639 | #endif |
f332db02 | 640 | |
f9496a7b RM |
641 | /* Remove _dl_rtld_map from the chain. */ |
642 | _dl_rtld_map.l_prev->l_next = _dl_rtld_map.l_next; | |
643 | if (_dl_rtld_map.l_next) | |
644 | _dl_rtld_map.l_next->l_prev = _dl_rtld_map.l_prev; | |
645 | ||
646 | if (_dl_rtld_map.l_opencount) | |
0200214b | 647 | { |
f9496a7b RM |
648 | /* Some DT_NEEDED entry referred to the interpreter object itself, so |
649 | put it back in the list of visible objects. We insert it into the | |
650 | chain in symbol search order because gdb uses the chain's order as | |
651 | its symbol search order. */ | |
77aba05b | 652 | i = 1; |
ceb2d9aa | 653 | while (main_map->l_searchlist[i] != &_dl_rtld_map) |
f9496a7b | 654 | ++i; |
ceb2d9aa UD |
655 | _dl_rtld_map.l_prev = main_map->l_searchlist[i - 1]; |
656 | _dl_rtld_map.l_next = (i + 1 < main_map->l_nsearchlist ? | |
657 | main_map->l_searchlist[i + 1] : NULL); | |
f9496a7b RM |
658 | assert (_dl_rtld_map.l_prev->l_next == _dl_rtld_map.l_next); |
659 | _dl_rtld_map.l_prev->l_next = &_dl_rtld_map; | |
4d02a5b1 | 660 | if (_dl_rtld_map.l_next) |
f9496a7b RM |
661 | { |
662 | assert (_dl_rtld_map.l_next->l_prev == _dl_rtld_map.l_prev); | |
663 | _dl_rtld_map.l_next->l_prev = &_dl_rtld_map; | |
664 | } | |
0200214b | 665 | } |
d66e34cd | 666 | |
c84142e8 UD |
667 | /* Now let us see whether all libraries are available in the |
668 | versions we need. */ | |
669 | { | |
993b3242 UD |
670 | struct version_check_args args; |
671 | args.doexit = mode == normal; | |
672 | args.main_map = main_map; | |
673 | _dl_receive_error (print_missing_version, version_check_doit, &args); | |
c84142e8 UD |
674 | } |
675 | ||
2de99474 | 676 | if (mode != normal) |
0200214b RM |
677 | { |
678 | /* We were run just to list the shared libraries. It is | |
679 | important that we do this before real relocation, because the | |
680 | functions we call below for output may no longer work properly | |
681 | after relocation. */ | |
0200214b RM |
682 | if (! _dl_loaded->l_info[DT_NEEDED]) |
683 | _dl_sysdep_message ("\t", "statically linked\n", NULL); | |
684 | else | |
ceb2d9aa UD |
685 | { |
686 | struct link_map *l; | |
687 | ||
688 | for (l = _dl_loaded->l_next; l; l = l->l_next) | |
689 | if (l->l_opencount == 0) | |
690 | /* The library was not found. */ | |
691 | _dl_sysdep_message ("\t", l->l_libname->name, " => not found\n", | |
692 | NULL); | |
693 | else | |
694 | { | |
695 | char buf[20], *bp; | |
696 | buf[sizeof buf - 1] = '\0'; | |
af6f3906 | 697 | bp = _itoa_word (l->l_addr, &buf[sizeof buf - 1], 16, 0); |
ceb2d9aa UD |
698 | while ((size_t) (&buf[sizeof buf - 1] - bp) |
699 | < sizeof l->l_addr * 2) | |
700 | *--bp = '0'; | |
701 | _dl_sysdep_message ("\t", l->l_libname->name, " => ", | |
702 | l->l_name, " (0x", bp, ")\n", NULL); | |
703 | } | |
704 | } | |
1a3a58fd | 705 | |
2de99474 | 706 | if (mode != trace) |
cddcfecf RM |
707 | for (i = 1; i < _dl_argc; ++i) |
708 | { | |
709 | const ElfW(Sym) *ref = NULL; | |
710 | ElfW(Addr) loadbase = _dl_lookup_symbol (_dl_argv[i], &ref, | |
711 | &_dl_default_scope[2], | |
dcf0671d | 712 | "argument", |
a2b08ee5 | 713 | ELF_MACHINE_JMP_SLOT); |
cddcfecf RM |
714 | char buf[20], *bp; |
715 | buf[sizeof buf - 1] = '\0'; | |
af6f3906 | 716 | bp = _itoa_word (ref->st_value, &buf[sizeof buf - 1], 16, 0); |
14bab8de | 717 | while ((size_t) (&buf[sizeof buf - 1] - bp) < sizeof loadbase * 2) |
cddcfecf RM |
718 | *--bp = '0'; |
719 | _dl_sysdep_message (_dl_argv[i], " found at 0x", bp, NULL); | |
720 | buf[sizeof buf - 1] = '\0'; | |
af6f3906 | 721 | bp = _itoa_word (loadbase, &buf[sizeof buf - 1], 16, 0); |
14bab8de | 722 | while ((size_t) (&buf[sizeof buf - 1] - bp) < sizeof loadbase * 2) |
cddcfecf RM |
723 | *--bp = '0'; |
724 | _dl_sysdep_message (" in object at 0x", bp, "\n", NULL); | |
725 | } | |
ce37fa88 | 726 | else |
fd26970f | 727 | { |
ce37fa88 UD |
728 | if (lazy >= 0) |
729 | { | |
730 | /* We have to do symbol dependency testing. */ | |
731 | struct relocate_args args; | |
732 | struct link_map *l; | |
993b3242 | 733 | |
ce37fa88 | 734 | args.lazy = lazy; |
fd26970f | 735 | |
ce37fa88 UD |
736 | l = _dl_loaded; |
737 | while (l->l_next) | |
738 | l = l->l_next; | |
739 | do | |
740 | { | |
741 | if (l != &_dl_rtld_map && l->l_opencount > 0) | |
742 | { | |
743 | args.l = l; | |
744 | _dl_receive_error (print_unresolved, relocate_doit, | |
745 | &args); | |
746 | *_dl_global_scope_end = NULL; | |
747 | } | |
748 | l = l->l_prev; | |
749 | } while (l); | |
750 | } | |
751 | ||
752 | #define VERNEEDTAG (DT_NUM + DT_PROCNUM + DT_VERSIONTAGIDX (DT_VERNEED)) | |
120b4c49 | 753 | if (version_info) |
fd26970f | 754 | { |
ce37fa88 UD |
755 | /* Print more information. This means here, print information |
756 | about the versions needed. */ | |
757 | int first = 1; | |
758 | struct link_map *map = _dl_loaded; | |
759 | ||
760 | for (map = _dl_loaded; map != NULL; map = map->l_next) | |
fd26970f | 761 | { |
f41c8091 | 762 | const char *strtab; |
ce37fa88 | 763 | ElfW(Dyn) *dyn = map->l_info[VERNEEDTAG]; |
f41c8091 UD |
764 | ElfW(Verneed) *ent; |
765 | ||
766 | if (dyn == NULL) | |
767 | continue; | |
768 | ||
769 | strtab = (const char *) | |
770 | (map->l_addr + map->l_info[DT_STRTAB]->d_un.d_ptr); | |
771 | ent = (ElfW(Verneed) *) (map->l_addr + dyn->d_un.d_ptr); | |
ce37fa88 | 772 | |
f41c8091 | 773 | if (first) |
ce37fa88 | 774 | { |
f41c8091 UD |
775 | _dl_sysdep_message ("\n\tVersion information:\n", NULL); |
776 | first = 0; | |
777 | } | |
ce37fa88 | 778 | |
f41c8091 UD |
779 | _dl_sysdep_message ("\t", (map->l_name[0] |
780 | ? map->l_name : _dl_argv[0]), | |
781 | ":\n", NULL); | |
782 | ||
783 | while (1) | |
784 | { | |
785 | ElfW(Vernaux) *aux; | |
786 | struct link_map *needed; | |
ce37fa88 | 787 | |
f41c8091 UD |
788 | needed = find_needed (strtab + ent->vn_file); |
789 | aux = (ElfW(Vernaux) *) ((char *) ent + ent->vn_aux); | |
ce37fa88 UD |
790 | |
791 | while (1) | |
792 | { | |
f41c8091 UD |
793 | const char *fname = NULL; |
794 | ||
795 | _dl_sysdep_message ("\t\t", | |
796 | strtab + ent->vn_file, | |
797 | " (", strtab + aux->vna_name, | |
798 | ") ", | |
799 | (aux->vna_flags | |
800 | & VER_FLG_WEAK | |
801 | ? "[WEAK] " : ""), | |
802 | "=> ", NULL); | |
803 | ||
804 | if (needed != NULL | |
805 | && match_version (strtab+aux->vna_name, needed)) | |
806 | fname = needed->l_name; | |
807 | ||
808 | _dl_sysdep_message (fname ?: "not found", "\n", | |
809 | NULL); | |
ce37fa88 | 810 | |
f41c8091 UD |
811 | if (aux->vna_next == 0) |
812 | /* No more symbols. */ | |
ce37fa88 UD |
813 | break; |
814 | ||
f41c8091 UD |
815 | /* Next symbol. */ |
816 | aux = (ElfW(Vernaux) *) ((char *) aux | |
817 | + aux->vna_next); | |
ce37fa88 | 818 | } |
f41c8091 UD |
819 | |
820 | if (ent->vn_next == 0) | |
821 | /* No more dependencies. */ | |
822 | break; | |
823 | ||
824 | /* Next dependency. */ | |
825 | ent = (ElfW(Verneed) *) ((char *) ent + ent->vn_next); | |
ce37fa88 | 826 | } |
fd26970f | 827 | } |
ce37fa88 | 828 | } |
fd26970f | 829 | } |
d66e34cd | 830 | |
0200214b RM |
831 | _exit (0); |
832 | } | |
86d2c878 | 833 | |
ba79d61b RM |
834 | { |
835 | /* Now we have all the objects loaded. Relocate them all except for | |
836 | the dynamic linker itself. We do this in reverse order so that copy | |
837 | relocs of earlier objects overwrite the data written by later | |
838 | objects. We do not re-relocate the dynamic linker itself in this | |
839 | loop because that could result in the GOT entries for functions we | |
840 | call being changed, and that would break us. It is safe to relocate | |
841 | the dynamic linker out of order because it has no copy relocs (we | |
842 | know that because it is self-contained). */ | |
843 | ||
ceb2d9aa | 844 | struct link_map *l; |
ba79d61b RM |
845 | l = _dl_loaded; |
846 | while (l->l_next) | |
847 | l = l->l_next; | |
848 | do | |
849 | { | |
850 | if (l != &_dl_rtld_map) | |
851 | { | |
852 | _dl_relocate_object (l, _dl_object_relocation_scope (l), lazy); | |
853 | *_dl_global_scope_end = NULL; | |
854 | } | |
855 | l = l->l_prev; | |
856 | } while (l); | |
857 | ||
858 | /* Do any necessary cleanups for the startup OS interface code. | |
859 | We do these now so that no calls are made after rtld re-relocation | |
860 | which might be resolved to different functions than we expect. | |
861 | We cannot do this before relocating the other objects because | |
862 | _dl_relocate_object might need to call `mprotect' for DT_TEXTREL. */ | |
863 | _dl_sysdep_start_cleanup (); | |
864 | ||
865 | if (_dl_rtld_map.l_opencount > 0) | |
866 | /* There was an explicit ref to the dynamic linker as a shared lib. | |
867 | Re-relocate ourselves with user-controlled symbol definitions. */ | |
868 | _dl_relocate_object (&_dl_rtld_map, &_dl_default_scope[2], 0); | |
869 | } | |
ac16e905 | 870 | |
4d6acc61 RM |
871 | { |
872 | /* Initialize _r_debug. */ | |
873 | struct r_debug *r = _dl_debug_initialize (_dl_rtld_map.l_addr); | |
ceb2d9aa | 874 | struct link_map *l; |
4d6acc61 RM |
875 | |
876 | l = _dl_loaded; | |
ec42724d RM |
877 | |
878 | #ifdef ELF_MACHINE_DEBUG_SETUP | |
879 | ||
880 | /* Some machines (e.g. MIPS) don't use DT_DEBUG in this way. */ | |
881 | ||
882 | ELF_MACHINE_DEBUG_SETUP (l, r); | |
883 | ELF_MACHINE_DEBUG_SETUP (&_dl_rtld_map, r); | |
884 | ||
885 | #else | |
886 | ||
4d6acc61 RM |
887 | if (l->l_info[DT_DEBUG]) |
888 | /* There is a DT_DEBUG entry in the dynamic section. Fill it in | |
889 | with the run-time address of the r_debug structure */ | |
890 | l->l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r; | |
891 | ||
d746b89c RM |
892 | /* Fill in the pointer in the dynamic linker's own dynamic section, in |
893 | case you run gdb on the dynamic linker directly. */ | |
894 | if (_dl_rtld_map.l_info[DT_DEBUG]) | |
895 | _dl_rtld_map.l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r; | |
896 | ||
ec42724d RM |
897 | #endif |
898 | ||
4d6acc61 RM |
899 | /* Notify the debugger that all objects are now mapped in. */ |
900 | r->r_state = RT_ADD; | |
901 | _dl_debug_state (); | |
902 | } | |
0200214b | 903 | |
3996f34b UD |
904 | /* Now enable profiling if needed. */ |
905 | if (_dl_profile_map != NULL) | |
906 | /* We must prepare the profiling. */ | |
907 | _dl_start_profile (_dl_profile_map, _dl_profile_output); | |
908 | ||
d66e34cd RM |
909 | /* Once we return, _dl_sysdep_start will invoke |
910 | the DT_INIT functions and then *USER_ENTRY. */ | |
911 | } | |
fd26970f UD |
912 | \f |
913 | /* This is a little helper function for resolving symbols while | |
914 | tracing the binary. */ | |
915 | static void | |
c84142e8 UD |
916 | print_unresolved (int errcode __attribute__ ((unused)), const char *objname, |
917 | const char *errstring) | |
fd26970f | 918 | { |
3996f34b UD |
919 | if (objname[0] == '\0') |
920 | objname = _dl_argv[0] ?: "<main program>"; | |
fd26970f UD |
921 | _dl_sysdep_error (errstring, " (", objname, ")\n", NULL); |
922 | } | |
c84142e8 UD |
923 | \f |
924 | /* This is a little helper function for resolving symbols while | |
925 | tracing the binary. */ | |
926 | static void | |
927 | print_missing_version (int errcode __attribute__ ((unused)), | |
928 | const char *objname, const char *errstring) | |
929 | { | |
930 | _dl_sysdep_error (_dl_argv[0] ?: "<program name unknown>", ": ", | |
931 | objname, ": ", errstring, "\n", NULL); | |
932 | } | |
ea278354 | 933 | \f |
7dea968e UD |
934 | /* Nonzero if any of the debugging options is enabled. */ |
935 | static int any_debug; | |
936 | ||
b5efde2f UD |
937 | /* Process the string given as the parameter which explains which debugging |
938 | options are enabled. */ | |
939 | static void | |
14c44e2e | 940 | process_dl_debug (const char *dl_debug) |
b5efde2f | 941 | { |
14c44e2e UD |
942 | size_t len; |
943 | #define separators " ,:" | |
b5efde2f UD |
944 | do |
945 | { | |
14c44e2e | 946 | len = 0; |
b5efde2f | 947 | /* Skip separating white spaces and commas. */ |
14c44e2e | 948 | dl_debug += strspn (dl_debug, separators); |
b5efde2f UD |
949 | if (*dl_debug != '\0') |
950 | { | |
14c44e2e UD |
951 | len = strcspn (dl_debug, separators); |
952 | ||
953 | switch (len) | |
b5efde2f | 954 | { |
14c44e2e UD |
955 | case 4: |
956 | if (memcmp (dl_debug, "help", 4) == 0) | |
957 | { | |
958 | _dl_sysdep_message ("\ | |
08b511e6 | 959 | Valid options for the LD_DEBUG environment variable are:\n\ |
b5efde2f | 960 | \n\ |
0c367d92 | 961 | bindings display information about symbol binding\n\ |
8193034b | 962 | files display processing of files and libraries\n\ |
0c367d92 UD |
963 | help display this help message and exit\n\ |
964 | libs display library search paths\n\ | |
8193034b | 965 | reloc display relocation processing\n\ |
de100ca7 | 966 | symbols display symbol table processing\n\ |
8193034b | 967 | versions display version dependencies\n\ |
0c367d92 UD |
968 | \n\ |
969 | To direct the debugging output into a file instead of standard output\n\ | |
970 | a filename can be specified using the LD_DEBUG_OUTPUT environment variable.\n", | |
971 | NULL); | |
14c44e2e UD |
972 | _exit (0); |
973 | } | |
77aba05b | 974 | |
14c44e2e UD |
975 | if (memcmp (dl_debug, "libs", 4) == 0) |
976 | { | |
977 | _dl_debug_libs = 1; | |
978 | _dl_debug_impcalls = 1; | |
979 | any_debug = 1; | |
980 | continue; | |
981 | } | |
982 | break; | |
983 | ||
984 | case 5: | |
985 | if (memcmp (dl_debug, "reloc", 5) == 0) | |
986 | { | |
987 | _dl_debug_reloc = 1; | |
988 | _dl_debug_impcalls = 1; | |
989 | any_debug = 1; | |
990 | continue; | |
991 | } | |
992 | ||
993 | if (memcmp (dl_debug, "files", 5) == 0) | |
994 | { | |
995 | _dl_debug_files = 1; | |
996 | _dl_debug_impcalls = 1; | |
997 | any_debug = 1; | |
998 | continue; | |
999 | } | |
1000 | break; | |
77aba05b | 1001 | |
14c44e2e UD |
1002 | case 7: |
1003 | if (memcmp (dl_debug, "symbols", 7) == 0) | |
1004 | { | |
1005 | _dl_debug_symbols = 1; | |
1006 | _dl_debug_impcalls = 1; | |
1007 | any_debug = 1; | |
1008 | continue; | |
1009 | } | |
1010 | break; | |
77aba05b | 1011 | |
14c44e2e UD |
1012 | case 8: |
1013 | if (memcmp (dl_debug, "bindings", 8) == 0) | |
1014 | { | |
1015 | _dl_debug_bindings = 1; | |
1016 | _dl_debug_impcalls = 1; | |
1017 | any_debug = 1; | |
1018 | continue; | |
1019 | } | |
1020 | ||
1021 | if (memcmp (dl_debug, "versions", 8) == 0) | |
1022 | { | |
1023 | _dl_debug_versions = 1; | |
1024 | _dl_debug_impcalls = 1; | |
1025 | any_debug = 1; | |
1026 | continue; | |
1027 | } | |
1028 | break; | |
1029 | ||
1030 | default: | |
1031 | break; | |
77aba05b | 1032 | } |
14c44e2e UD |
1033 | |
1034 | { | |
1035 | /* Display a warning and skip everything until next separator. */ | |
1036 | char *startp = strndupa (dl_debug, len); | |
1037 | _dl_sysdep_error ("warning: debug option `", startp, | |
1038 | "' unknown; try LD_DEBUG=help\n", NULL); | |
1039 | } | |
b5efde2f UD |
1040 | } |
1041 | } | |
14c44e2e | 1042 | while (*(dl_debug += len) != '\0'); |
b5efde2f UD |
1043 | } |
1044 | \f | |
ea278354 UD |
1045 | /* Process all environments variables the dynamic linker must recognize. |
1046 | Since all of them start with `LD_' we are a bit smarter while finding | |
1047 | all the entries. */ | |
1048 | static void | |
1049 | process_envvars (enum mode *modep, int *lazyp) | |
1050 | { | |
1051 | char **runp = NULL; | |
1052 | char *envline; | |
1053 | enum mode mode = normal; | |
1054 | int bind_now = 0; | |
7dea968e | 1055 | char *debug_output = NULL; |
ea278354 UD |
1056 | |
1057 | /* This is the default place for profiling data file. */ | |
1058 | _dl_profile_output = "/var/tmp"; | |
1059 | ||
1060 | while ((envline = _dl_next_ld_env_entry (&runp)) != NULL) | |
1061 | { | |
14c44e2e | 1062 | size_t len = strcspn (envline, "=") - 3; |
ea278354 | 1063 | |
14c44e2e | 1064 | switch (len) |
ea278354 | 1065 | { |
14c44e2e UD |
1066 | case 4: |
1067 | /* Warning level, verbose or not. */ | |
1068 | if (memcmp (&envline[3], "WARN", 4) == 0) | |
1069 | _dl_verbose = envline[8] != '\0'; | |
1070 | break; | |
ea278354 | 1071 | |
14c44e2e UD |
1072 | case 5: |
1073 | /* Debugging of the dynamic linker? */ | |
1074 | if (memcmp (&envline[3], "DEBUG", 5) == 0) | |
1075 | process_dl_debug (&envline[9]); | |
1076 | break; | |
b5efde2f | 1077 | |
14c44e2e UD |
1078 | case 7: |
1079 | /* Print information about versions. */ | |
1080 | if (memcmp (&envline[3], "VERBOSE", 7) == 0) | |
1081 | { | |
1082 | version_info = envline[11] != '\0'; | |
1083 | break; | |
1084 | } | |
7dea968e | 1085 | |
14c44e2e UD |
1086 | /* List of objects to be preloaded. */ |
1087 | if (memcmp (&envline[3], "PRELOAD", 7) == 0) | |
1088 | { | |
1089 | preloadlist = &envline[11]; | |
1090 | break; | |
1091 | } | |
120b4c49 | 1092 | |
14c44e2e UD |
1093 | /* Which shared object shall be profiled. */ |
1094 | if (memcmp (&envline[3], "PROFILE", 7) == 0) | |
1095 | { | |
1096 | _dl_profile = &envline[11]; | |
1097 | if (*_dl_profile == '\0') | |
1098 | _dl_profile = NULL; | |
1099 | } | |
1100 | break; | |
120b4c49 | 1101 | |
14c44e2e UD |
1102 | case 8: |
1103 | /* Do we bind early? */ | |
1104 | if (memcmp (&envline[3], "BIND_NOW", 8) == 0) | |
1105 | bind_now = 1; | |
1106 | break; | |
ea278354 | 1107 | |
14c44e2e UD |
1108 | case 9: |
1109 | /* Test whether we want to see the content of the auxiliary | |
1110 | array passed up from the kernel. */ | |
1111 | if (memcmp (&envline[3], "SHOW_AUXV", 9) == 0) | |
1112 | _dl_show_auxv (); | |
1113 | break; | |
ea278354 | 1114 | |
14c44e2e UD |
1115 | case 12: |
1116 | /* Where to place the profiling data file. */ | |
1117 | if (memcmp (&envline[3], "DEBUG_OUTPUT", 12) == 0) | |
1118 | { | |
1119 | debug_output = &envline[16]; | |
1120 | break; | |
1121 | } | |
ea278354 | 1122 | |
14c44e2e UD |
1123 | /* The library search path. */ |
1124 | if (memcmp (&envline[3], "LIBRARY_PATH", 12) == 0) | |
1125 | library_path = &envline[16]; | |
1126 | break; | |
ea278354 | 1127 | |
14c44e2e UD |
1128 | case 14: |
1129 | /* Where to place the profiling data file. */ | |
1130 | if (memcmp (&envline[3], "PROFILE_OUTPUT", 14) == 0) | |
1131 | { | |
1132 | _dl_profile_output = &envline[18]; | |
1133 | if (*_dl_profile_output == '\0') | |
1134 | _dl_profile_output = "/var/tmp"; | |
1135 | } | |
1136 | break; | |
120b4c49 | 1137 | |
14c44e2e UD |
1138 | case 20: |
1139 | /* The mode of the dynamic linker can be set. */ | |
1140 | if (memcmp (&envline[3], "TRACE_LOADED_OBJECTS", 20) == 0) | |
1141 | mode = trace; | |
1142 | break; | |
e2102c14 UD |
1143 | |
1144 | /* We might have some extra environment variable to handle. This | |
1145 | is tricky due to the pre-processing of the length of the name | |
1146 | in the switch statement here. The code here assumes that added | |
1147 | environment variables have a different length. */ | |
1148 | #ifdef EXTRA_LD_ENVVARS | |
1149 | EXTRA_LD_ENVVARS | |
1150 | #endif | |
ea278354 UD |
1151 | } |
1152 | } | |
1153 | ||
7dea968e UD |
1154 | /* If we have to run the dynamic linker in debugging mode and the |
1155 | LD_DEBUG_OUTPUT environment variable is given, we write the debug | |
1156 | messages to this file. */ | |
14c44e2e | 1157 | if (any_debug && debug_output != NULL && !__libc_enable_secure) |
7dea968e UD |
1158 | { |
1159 | _dl_debug_fd = __open (debug_output, O_WRONLY | O_APPEND | O_CREAT, | |
1160 | 0666); | |
1161 | if (_dl_debug_fd == -1) | |
1162 | /* We use standard output if opening the file failed. */ | |
1163 | _dl_debug_fd = STDOUT_FILENO; | |
1164 | } | |
1165 | ||
ea278354 UD |
1166 | /* LAZY is determined by the environment variable LD_WARN and |
1167 | LD_BIND_NOW if we trace the binary. */ | |
1168 | if (mode == trace) | |
1169 | *lazyp = _dl_verbose ? !bind_now : -1; | |
1170 | else | |
1171 | *lazyp = !__libc_enable_secure && !bind_now; | |
1172 | ||
1173 | *modep = mode; | |
1174 | } |