1 /* Run-time dynamic linker data structures for loaded ELF shared objects.
2 Copyright (C) 1995-2023 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 #ifndef _LDSODEFS_H
20 #define _LDSODEFS_H 1
21
22 #include <features.h>
23
24 #include <stdbool.h>
25 #define __need_size_t
26 #define __need_NULL
27 #include <stddef.h>
28 #include <string.h>
29 #include <stdint.h>
30
31 #include <elf.h>
32 #include <dlfcn.h>
33 #include <fpu_control.h>
34 #include <sys/mman.h>
35 #include <link.h>
36 #include <dl-lookupcfg.h>
37 #include <dl-sysdep.h>
38 #include <dl-fixup-attribute.h>
39 #include <libc-lock.h>
40 #include <hp-timing.h>
41 #include <list_t.h>
42
43 __BEGIN_DECLS
44
45 #define VERSYMIDX(sym) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGIDX (sym))
46 #define VALIDX(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM \
47 + DT_EXTRANUM + DT_VALTAGIDX (tag))
48 #define ADDRIDX(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM \
49 + DT_EXTRANUM + DT_VALNUM + DT_ADDRTAGIDX (tag))
50
51 /* Type of GNU hash which the machine uses. */
52 #ifndef ELF_MACHINE_GNU_HASH_ADDRIDX
53 # define ELF_MACHINE_GNU_HASH_ADDRIDX ADDRIDX (DT_GNU_HASH)
54 #endif
55
56 /* Calculate the index of a symbol in GNU hash. */
57 #ifndef ELF_MACHINE_HASH_SYMIDX
58 # define ELF_MACHINE_HASH_SYMIDX(map, hasharr) \
59 ((hasharr) - (map)->l_gnu_chain_zero)
60 #endif
61
62 /* Setup MIPS xhash. Defined only for MIPS. */
63 #ifndef ELF_MACHINE_XHASH_SETUP
64 # define ELF_MACHINE_XHASH_SETUP(hash32, symbias, map) \
65 ((void) (hash32), (void) (symbias), (void) (map))
66 #endif
67
68 /* We use this macro to refer to ELF types independent of the native wordsize.
69 `ElfW(TYPE)' is used in place of `Elf32_TYPE' or `Elf64_TYPE'. */
70 #define ELFW(type) _ElfW (ELF, __ELF_NATIVE_CLASS, type)
71
72 /* Return true if dynamic section in the shared library L should be
73 relocated. */
74
75 static inline bool
76 dl_relocate_ld (const struct link_map *l)
77 {
78 /* Don't relocate dynamic section if it is readonly */
79 return !(l->l_ld_readonly || DL_RO_DYN_SECTION);
80 }
81
82 /* All references to the value of l_info[DT_PLTGOT],
83 l_info[DT_STRTAB], l_info[DT_SYMTAB], l_info[DT_RELA],
84 l_info[DT_REL], l_info[DT_JMPREL], and l_info[VERSYMIDX (DT_VERSYM)]
85 have to be accessed via the D_PTR macro. The macro is needed since for
86 most architectures the entry is already relocated - but for some not
87 and we need to relocate at access time. */
88 #define D_PTR(map, i) \
89 ((map)->i->d_un.d_ptr + (dl_relocate_ld (map) ? 0 : (map)->l_addr))
90
91 /* Result of the lookup functions and how to retrieve the base address. */
92 typedef struct link_map *lookup_t;
93 #define LOOKUP_VALUE(map) map
94 #define LOOKUP_VALUE_ADDRESS(map, set) ((set) || (map) ? (map)->l_addr : 0)
95
96 /* Calculate the address of symbol REF using the base address from map MAP,
97 if non-NULL. Don't check for NULL map if MAP_SET is TRUE. */
98 #define SYMBOL_ADDRESS(map, ref, map_set) \
99 ((ref) == NULL ? 0 \
100 : (__glibc_unlikely ((ref)->st_shndx == SHN_ABS) ? 0 \
101 : LOOKUP_VALUE_ADDRESS (map, map_set)) + (ref)->st_value)
102
103 /* Type of a constructor function, in DT_INIT, DT_INIT_ARRAY,
104 DT_PREINIT_ARRAY. */
105 typedef void (*dl_init_t) (int, char **, char **);
106
107 /* Type of a constructor function, in DT_FINI, DT_FINI_ARRAY. */
108 typedef void (*fini_t) (void);
109
110 /* On some architectures a pointer to a function is not just a pointer
111 to the actual code of the function but rather an architecture
112 specific descriptor. */
113 #ifndef ELF_FUNCTION_PTR_IS_SPECIAL
114 # define DL_SYMBOL_ADDRESS(map, ref) \
115 (void *) SYMBOL_ADDRESS (map, ref, false)
116 # define DL_LOOKUP_ADDRESS(addr) ((ElfW(Addr)) (addr))
117 # define DL_CALL_DT_INIT(map, start, argc, argv, env) \
118 ((dl_init_t) (start)) (argc, argv, env)
119 # define DL_CALL_DT_FINI(map, start) ((fini_t) (start)) ()
120 #endif
121
122 /* On some architectures dladdr can't use st_size of all symbols this way. */
123 #define DL_ADDR_SYM_MATCH(L, SYM, MATCHSYM, ADDR) \
124 ((ADDR) >= (L)->l_addr + (SYM)->st_value \
125 && ((((SYM)->st_shndx == SHN_UNDEF || (SYM)->st_size == 0) \
126 && (ADDR) == (L)->l_addr + (SYM)->st_value) \
127 || (ADDR) < (L)->l_addr + (SYM)->st_value + (SYM)->st_size) \
128 && ((MATCHSYM) == NULL || (MATCHSYM)->st_value < (SYM)->st_value))
129
130 /* According to the ELF gABI no STV_HIDDEN or STV_INTERNAL symbols are
131 expected to be present in dynamic symbol tables as they should have
132 been either removed or converted to STB_LOCAL binding by the static
133 linker. However some GNU binutils versions produce such symbols in
134 some cases. To prevent such symbols present in a buggy binary from
135 preempting global symbols we filter them out with this predicate. */
136 static __always_inline bool
137 dl_symbol_visibility_binds_local_p (const ElfW(Sym) *sym)
138 {
139 return (ELFW(ST_VISIBILITY) (sym->st_other) == STV_HIDDEN
140 || ELFW(ST_VISIBILITY) (sym->st_other) == STV_INTERNAL);
141 }
142
143 /* Unmap a loaded object, called by _dl_close (). */
144 #ifndef DL_UNMAP_IS_SPECIAL
145 # define DL_UNMAP(map) _dl_unmap_segments (map)
146 #endif
147
148 /* Reloc type classes as returned by elf_machine_type_class().
149 ELF_RTYPE_CLASS_PLT means this reloc should not be satisfied by
150 some PLT symbol, ELF_RTYPE_CLASS_COPY means this reloc should not be
151 satisfied by any symbol in the executable. Some architectures do
152 not support copy relocations. In this case we define the macro to
153 zero so that the code for handling them gets automatically optimized
154 out. */
155 #define ELF_RTYPE_CLASS_PLT 1
156 #ifndef DL_NO_COPY_RELOCS
157 # define ELF_RTYPE_CLASS_COPY 2
158 #else
159 # define ELF_RTYPE_CLASS_COPY 0
160 #endif
161
162 /* ELF uses the PF_x macros to specify the segment permissions, mmap
163 uses PROT_xxx. In most cases the three macros have the values 1, 2,
164 and 3 but not in a matching order. The following macros allows
165 converting from the PF_x values to PROT_xxx values. */
166 #define PF_TO_PROT \
167 ((PROT_READ << (PF_R * 4)) \
168 | (PROT_WRITE << (PF_W * 4)) \
169 | (PROT_EXEC << (PF_X * 4)) \
170 | ((PROT_READ | PROT_WRITE) << ((PF_R | PF_W) * 4)) \
171 | ((PROT_READ | PROT_EXEC) << ((PF_R | PF_X) * 4)) \
172 | ((PROT_WRITE | PROT_EXEC) << (PF_W | PF_X) * 4) \
173 | ((PROT_READ | PROT_WRITE | PROT_EXEC) << ((PF_R | PF_W | PF_X) * 4)))
174
175 /* The filename itself, or the main program name, if available. */
176 #define DSO_FILENAME(name) ((name)[0] ? (name) \
177 : (rtld_progname ?: "<main program>"))
178
179 #define RTLD_PROGNAME (rtld_progname ?: "<program name unknown>")
180
181 /* For the version handling we need an array with only names and their
182 hash values. */
183 struct r_found_version
184 {
185 const char *name;
186 ElfW(Word) hash;
187
188 int hidden;
189 const char *filename;
190 };
191
192 /* We want to cache information about the searches for shared objects. */
193
194 enum r_dir_status { unknown, nonexisting, existing };
195
196 struct r_search_path_elem
197 {
198 /* This link is only used in the `all_dirs' member of `r_search_path'. */
199 struct r_search_path_elem *next;
200
201 /* Strings saying where the definition came from. */
202 const char *what;
203 const char *where;
204
205 /* Basename for this search path element. The string must end with
206 a slash character. */
207 const char *dirname;
208 size_t dirnamelen;
209
210 enum r_dir_status status[0];
211 };
212
213 struct r_strlenpair
214 {
215 const char *str;
216 size_t len;
217 };
218
219
220 /* A data structure for a simple single linked list of strings. */
221 struct libname_list
222 {
223 const char *name; /* Name requested (before search). */
224 struct libname_list *next; /* Link to next name for this object. */
225 int dont_free; /* Flag whether this element should be freed
226 if the object is not entirely unloaded. */
227 };
228
229
230 /* DSO sort algorithm to use (check dl-sort-maps.c). */
231 enum dso_sort_algorithm
232 {
233 dso_sort_algorithm_original,
234 dso_sort_algorithm_dfs
235 };
236
237 struct audit_ifaces
238 {
239 void (*activity) (uintptr_t *, unsigned int);
240 char *(*objsearch) (const char *, uintptr_t *, unsigned int);
241 unsigned int (*objopen) (struct link_map *, Lmid_t, uintptr_t *);
242 void (*preinit) (uintptr_t *);
243 union
244 {
245 uintptr_t (*symbind32) (Elf32_Sym *, unsigned int, uintptr_t *,
246 uintptr_t *, unsigned int *, const char *);
247 uintptr_t (*symbind64) (Elf64_Sym *, unsigned int, uintptr_t *,
248 uintptr_t *, unsigned int *, const char *);
249 };
250 union
251 {
252 #ifdef ARCH_PLTENTER_MEMBERS
253 ARCH_PLTENTER_MEMBERS;
254 #endif
255 };
256 union
257 {
258 #ifdef ARCH_PLTEXIT_MEMBERS
259 ARCH_PLTEXIT_MEMBERS;
260 #endif
261 };
262 unsigned int (*objclose) (uintptr_t *);
263
264 struct audit_ifaces *next;
265 };
266
267
268 /* Test whether given NAME matches any of the names of the given object. */
269 extern int _dl_name_match_p (const char *__name, const struct link_map *__map)
270 attribute_hidden;
271
272 /* Compute next higher prime number. */
273 extern unsigned long int _dl_higher_prime_number (unsigned long int n)
274 attribute_hidden;
275
276 /* A stripped down strtoul-like implementation. */
277 uint64_t _dl_strtoul (const char *, char **) attribute_hidden;
278
279 /* Function used as argument for `_dl_receive_error' function. The
280 arguments are the error code, error string, and the objname the
281 error occurred in. */
282 typedef void (*receiver_fct) (int, const char *, const char *);
283
284 /* Internal functions of the run-time dynamic linker.
285 These can be accessed if you link again the dynamic linker
286 as a shared library, as in `-lld' or `/lib/ld.so' explicitly;
287 but are not normally of interest to user programs.
288
289 The `-ldl' library functions in <dlfcn.h> provide a simple
290 user interface to run-time dynamic linking. */
291
292
293 #ifndef SHARED
294 # define EXTERN extern
295 # define GL(name) _##name
296 #else
297 # define EXTERN
298 # if IS_IN (rtld)
299 # define GL(name) _rtld_local._##name
300 # else
301 # define GL(name) _rtld_global._##name
302 # endif
303 struct rtld_global
304 {
305 #endif
306 /* Don't change the order of the following elements. 'dl_loaded'
307 must remain the first element. Forever. */
308
309 /* Non-shared code has no support for multiple namespaces. */
310 #ifdef SHARED
311 # define DL_NNS 16
312 #else
313 # define DL_NNS 1
314 #endif
315 EXTERN struct link_namespaces
316 {
317 /* A pointer to the map for the main map. */
318 struct link_map *_ns_loaded;
319 /* Number of object in the _dl_loaded list. */
320 unsigned int _ns_nloaded;
321 /* Direct pointer to the searchlist of the main object. */
322 struct r_scope_elem *_ns_main_searchlist;
323 /* This is zero at program start to signal that the global scope map is
324 allocated by rtld. Later it keeps the size of the map. It might be
325 reset if in _dl_close if the last global object is removed. */
326 unsigned int _ns_global_scope_alloc;
327
328 /* During dlopen, this is the number of objects that still need to
329 be added to the global scope map. It has to be taken into
330 account when resizing the map, for future map additions after
331 recursive dlopen calls from ELF constructors. */
332 unsigned int _ns_global_scope_pending_adds;
333
334 /* Once libc.so has been loaded into the namespace, this points to
335 its link map. */
336 struct link_map *libc_map;
337
338 /* Search table for unique objects. */
339 struct unique_sym_table
340 {
341 __rtld_lock_define_recursive (, lock)
342 struct unique_sym
343 {
344 uint32_t hashval;
345 const char *name;
346 const ElfW(Sym) *sym;
347 const struct link_map *map;
348 } *entries;
349 size_t size;
350 size_t n_elements;
351 void (*free) (void *);
352 } _ns_unique_sym_table;
353 /* Keep track of changes to each namespace' list. */
354 struct r_debug_extended _ns_debug;
355 } _dl_ns[DL_NNS];
356 /* One higher than index of last used namespace. */
357 EXTERN size_t _dl_nns;
358
359 /* During the program run we must not modify the global data of
360 loaded shared object simultaneously in two threads. Therefore we
361 protect `_dl_open' and `_dl_close' in dl-close.c.
362
363 This must be a recursive lock since the initializer function of
364 the loaded object might as well require a call to this function.
365 At this time it is not anymore a problem to modify the tables. */
366 __rtld_lock_define_recursive (EXTERN, _dl_load_lock)
367 /* This lock is used to keep __dl_iterate_phdr from inspecting the
368 list of loaded objects while an object is added to or removed
369 from that list. */
370 __rtld_lock_define_recursive (EXTERN, _dl_load_write_lock)
371 /* This lock protects global and module specific TLS related data.
372 E.g. it is held in dlopen and dlclose when GL(dl_tls_generation),
373 GL(dl_tls_max_dtv_idx) or GL(dl_tls_dtv_slotinfo_list) are
374 accessed and when TLS related relocations are processed for a
375 module. It was introduced to keep pthread_create accessing TLS
376 state that is being set up. */
377 __rtld_lock_define_recursive (EXTERN, _dl_load_tls_lock)
378
379 /* Incremented whenever something may have been added to dl_loaded. */
380 EXTERN unsigned long long _dl_load_adds;
381
382 /* The object to be initialized first. */
383 EXTERN struct link_map *_dl_initfirst;
384
385 /* Map of shared object to be profiled. */
386 EXTERN struct link_map *_dl_profile_map;
387
388 /* Counters for the number of relocations performed. */
389 EXTERN unsigned long int _dl_num_relocations;
390 EXTERN unsigned long int _dl_num_cache_relocations;
391
392 /* List of search directories. */
393 EXTERN struct r_search_path_elem *_dl_all_dirs;
394
395 /* Structure describing the dynamic linker itself. */
396 EXTERN struct link_map _dl_rtld_map;
397 #ifdef SHARED
398 /* Used to store the audit information for the link map of the
399 dynamic loader. */
400 struct auditstate _dl_rtld_auditstate[DL_NNS];
401 #endif
402
403 #if !PTHREAD_IN_LIBC && defined SHARED \
404 && defined __rtld_lock_default_lock_recursive
405 EXTERN void (*_dl_rtld_lock_recursive) (void *);
406 EXTERN void (*_dl_rtld_unlock_recursive) (void *);
407 #endif
408
409 /* Get architecture specific definitions. */
410 #define PROCINFO_DECL
411 #ifndef PROCINFO_CLASS
412 # define PROCINFO_CLASS EXTERN
413 #endif
414 #include <dl-procruntime.c>
415
416 #if !PTHREAD_IN_LIBC
417 /* If loading a shared object requires that we make the stack executable
418 when it was not, we do it by calling this function.
419 It returns an errno code or zero on success. */
420 EXTERN int (*_dl_make_stack_executable_hook) (void **);
421 #endif
422
423 /* Prevailing state of the stack, PF_X indicating it's executable. */
424 EXTERN ElfW(Word) _dl_stack_flags;
425
426 /* Flag signalling whether there are gaps in the module ID allocation. */
427 EXTERN bool _dl_tls_dtv_gaps;
428 /* Highest dtv index currently needed. */
429 EXTERN size_t _dl_tls_max_dtv_idx;
430 /* Information about the dtv slots. */
431 EXTERN struct dtv_slotinfo_list
432 {
433 size_t len;
434 struct dtv_slotinfo_list *next;
435 struct dtv_slotinfo
436 {
437 size_t gen;
438 struct link_map *map;
439 } slotinfo[];
440 } *_dl_tls_dtv_slotinfo_list;
441 /* Number of modules in the static TLS block. */
442 EXTERN size_t _dl_tls_static_nelem;
443 /* Size actually allocated in the static TLS block. */
444 EXTERN size_t _dl_tls_static_used;
445 /* Remaining amount of static TLS that may be used for optimizing
446 dynamic TLS access (e.g. with TLSDESC). */
447 EXTERN size_t _dl_tls_static_optional;
448
449 /* Number of additional entries in the slotinfo array of each slotinfo
450 list element. A large number makes it almost certain take we never
451 have to iterate beyond the first element in the slotinfo list. */
452 #define TLS_SLOTINFO_SURPLUS (62)
453
454 /* Number of additional slots in the dtv allocated. */
455 #define DTV_SURPLUS (14)
456
457 /* Initial dtv of the main thread, not allocated with normal malloc. */
458 EXTERN void *_dl_initial_dtv;
459 /* Generation counter for the dtv. */
460 EXTERN size_t _dl_tls_generation;
461
462 #if !PTHREAD_IN_LIBC
463 EXTERN void (*_dl_init_static_tls) (struct link_map *);
464 #endif
465
466 /* Scopes to free after next THREAD_GSCOPE_WAIT (). */
467 EXTERN struct dl_scope_free_list
468 {
469 size_t count;
470 void *list[50];
471 } *_dl_scope_free_list;
472 #if PTHREAD_IN_LIBC
473 /* List of active thread stacks, with memory managed by glibc. */
474 EXTERN list_t _dl_stack_used;
475
476 /* List of thread stacks that were allocated by the application. */
477 EXTERN list_t _dl_stack_user;
478
479 /* List of queued thread stacks. */
480 EXTERN list_t _dl_stack_cache;
481
482 /* Total size of all stacks in the cache (sum over stackblock_size). */
483 EXTERN size_t _dl_stack_cache_actsize;
484
485 /* We need to record what list operations we are going to do so
486 that, in case of an asynchronous interruption due to a fork()
487 call, we can correct for the work. */
488 EXTERN uintptr_t _dl_in_flight_stack;
489
490 /* Mutex protecting the stack lists. */
491 EXTERN int _dl_stack_cache_lock;
492 #else
493 /* The total number of thread IDs currently in use, or on the list of
494 available thread IDs. */
495 EXTERN int _dl_pthread_num_threads;
496
497 /* Array of __pthread structures and its lock. */
498 EXTERN struct __pthread **_dl_pthread_threads;
499 __libc_rwlock_define (EXTERN, _dl_pthread_threads_lock)
500 #endif
501 #ifdef SHARED
502 };
503 # define __rtld_global_attribute__
504 # if IS_IN (rtld)
505 # ifdef HAVE_SDATA_SECTION
506 # define __rtld_local_attribute__ \
507 __attribute__ ((visibility ("hidden"), section (".sdata")))
508 # undef __rtld_global_attribute__
509 # define __rtld_global_attribute__ __attribute__ ((section (".sdata")))
510 # else
511 # define __rtld_local_attribute__ __attribute__ ((visibility ("hidden")))
512 # endif
513 extern struct rtld_global _rtld_local __rtld_local_attribute__;
514 # undef __rtld_local_attribute__
515 # endif
516 extern struct rtld_global _rtld_global __rtld_global_attribute__;
517 # undef __rtld_global_attribute__
518 #endif
519
520 #ifndef SHARED
521 # define GLRO(name) _##name
522 #else
523 # if IS_IN (rtld)
524 # define GLRO(name) _rtld_local_ro._##name
525 # else
526 # define GLRO(name) _rtld_global_ro._##name
527 # endif
528 struct rtld_global_ro
529 {
530 #endif
531
532 /* If nonzero the appropriate debug information is printed. */
533 EXTERN int _dl_debug_mask;
534 #define DL_DEBUG_LIBS (1 << 0)
535 #define DL_DEBUG_IMPCALLS (1 << 1)
536 #define DL_DEBUG_BINDINGS (1 << 2)
537 #define DL_DEBUG_SYMBOLS (1 << 3)
538 #define DL_DEBUG_VERSIONS (1 << 4)
539 #define DL_DEBUG_RELOC (1 << 5)
540 #define DL_DEBUG_FILES (1 << 6)
541 #define DL_DEBUG_STATISTICS (1 << 7)
542 #define DL_DEBUG_UNUSED (1 << 8)
543 #define DL_DEBUG_SCOPES (1 << 9)
544 /* These two are used only internally. */
545 #define DL_DEBUG_HELP (1 << 10)
546
547 /* Platform name. */
548 EXTERN const char *_dl_platform;
549 EXTERN size_t _dl_platformlen;
550
551 /* Cached value of `getpagesize ()'. */
552 EXTERN size_t _dl_pagesize;
553
554 /* Cached value of `sysconf (_SC_MINSIGSTKSZ)'. */
555 EXTERN size_t _dl_minsigstacksize;
556
557 /* Do we read from ld.so.cache? */
558 EXTERN int _dl_inhibit_cache;
559
560 /* Copy of the content of `_dl_main_searchlist' at startup time. */
561 EXTERN struct r_scope_elem _dl_initial_searchlist;
562
563 /* CLK_TCK as reported by the kernel. */
564 EXTERN int _dl_clktck;
565
566 /* If nonzero print warnings messages. */
567 EXTERN int _dl_verbose;
568
569 /* File descriptor to write debug messages to. */
570 EXTERN int _dl_debug_fd;
571
572 /* Do we do lazy relocations? */
573 EXTERN int _dl_lazy;
574
575 /* Nonzero if runtime lookups should not update the .got/.plt. */
576 EXTERN int _dl_bind_not;
577
578 /* Nonzero if references should be treated as weak during runtime
579 linking. */
580 EXTERN int _dl_dynamic_weak;
581
582 /* Default floating-point control word. */
583 EXTERN fpu_control_t _dl_fpu_control;
584
585 /* Mask for hardware capabilities that are available. */
586 EXTERN uint64_t _dl_hwcap;
587
588 #ifdef HAVE_AUX_VECTOR
589 /* Pointer to the auxv list supplied to the program at startup. */
590 EXTERN ElfW(auxv_t) *_dl_auxv;
591 #endif
592
593 /* Get architecture specific definitions. */
594 #include <dl-procinfo.c>
595
596 /* Names of shared object for which the RPATH should be ignored. */
597 EXTERN const char *_dl_inhibit_rpath;
598
599 /* Location of the binary. */
600 EXTERN const char *_dl_origin_path;
601
602 /* Size of the static TLS block. */
603 EXTERN size_t _dl_tls_static_size;
604
605 /* Alignment requirement of the static TLS block. */
606 EXTERN size_t _dl_tls_static_align;
607
608 /* Size of surplus space in the static TLS area for dynamically
609 loaded modules with IE-model TLS or for TLSDESC optimization.
610 See comments in elf/dl-tls.c where it is initialized. */
611 EXTERN size_t _dl_tls_static_surplus;
612
613 /* Name of the shared object to be profiled (if any). */
614 EXTERN const char *_dl_profile;
615 /* Filename of the output file. */
616 EXTERN const char *_dl_profile_output;
617
618 /* All search directories defined at startup. This is assigned a
619 non-NULL pointer by the ld.so startup code (after initialization
620 to NULL), so this can also serve as an indicator whether a copy
621 of ld.so is initialized and active. See the rtld_active function
622 below. */
623 EXTERN struct r_search_path_elem *_dl_init_all_dirs;
624
625 #ifdef NEED_DL_SYSINFO
626 /* Syscall handling improvements. This is very specific to x86. */
627 EXTERN uintptr_t _dl_sysinfo;
628 #endif
629
630 #ifdef NEED_DL_SYSINFO_DSO
631 /* The vsyscall page is a virtual DSO pre-mapped by the kernel.
632 This points to its ELF header. */
633 EXTERN const ElfW(Ehdr) *_dl_sysinfo_dso;
634
635 /* At startup time we set up the normal DSO data structure for it,
636 and this points to it. */
637 EXTERN struct link_map *_dl_sysinfo_map;
638
639 # define PROCINFO_DECL
640 # ifndef PROCINFO_CLASS
641 # define PROCINFO_CLASS EXTERN
642 # endif
643 # include <dl-vdso-setup.c>
644 #endif
645
646 /* Mask for more hardware capabilities that are available on some
647 platforms. */
648 EXTERN uint64_t _dl_hwcap2;
649
650 EXTERN enum dso_sort_algorithm _dl_dso_sort_algo;
651
652 #ifdef SHARED
653 /* We add a function table to _rtld_global which is then used to
654 call the function instead of going through the PLT. The result
655 is that we can avoid exporting the functions and we do not jump
656 PLT relocations in libc.so. */
657 void (*_dl_debug_printf) (const char *, ...)
658 __attribute__ ((__format__ (__printf__, 1, 2)));
659 void (*_dl_mcount) (ElfW(Addr) frompc, ElfW(Addr) selfpc);
660 lookup_t (*_dl_lookup_symbol_x) (const char *, struct link_map *,
661 const ElfW(Sym) **, struct r_scope_elem *[],
662 const struct r_found_version *, int, int,
663 struct link_map *);
664 void *(*_dl_open) (const char *file, int mode, const void *caller_dlopen,
665 Lmid_t nsid, int argc, char *argv[], char *env[]);
666 void (*_dl_close) (void *map);
667 /* libdl in a secondary namespace (after dlopen) must use
668 _dl_catch_error from the main namespace, so it has to be
669 exported in some way. */
670 int (*_dl_catch_error) (const char **objname, const char **errstring,
671 bool *mallocedp, void (*operate) (void *),
672 void *args);
673 /* libdl in a secondary namespace must use free from the base
674 namespace. */
675 void (*_dl_error_free) (void *);
676 void *(*_dl_tls_get_addr_soft) (struct link_map *);
677
678 /* Called from __libc_shared to deallocate malloc'ed memory. */
679 void (*_dl_libc_freeres) (void);
680
681 /* Implementation of _dl_find_object. The public entry point is in
682 libc, and this is patched by __rtld_static_init to support static
683 dlopen. */
684 int (*_dl_find_object) (void *, struct dl_find_object *);
685
686 /* Dynamic linker operations used after static dlopen. */
687 const struct dlfcn_hook *_dl_dlfcn_hook;
688
689 /* List of auditing interfaces. */
690 struct audit_ifaces *_dl_audit;
691 unsigned int _dl_naudit;
692 };
693 # define __rtld_global_attribute__
694 # if IS_IN (rtld)
695 # define __rtld_local_attribute__ __attribute__ ((visibility ("hidden")))
696 extern struct rtld_global_ro _rtld_local_ro
697 attribute_relro __rtld_local_attribute__;
698 extern struct rtld_global_ro _rtld_global_ro
699 attribute_relro __rtld_global_attribute__;
700 # undef __rtld_local_attribute__
701 # else
702 /* We cheat a bit here. We declare the variable as as const even
703 though it is at startup. */
704 extern const struct rtld_global_ro _rtld_global_ro
705 attribute_relro __rtld_global_attribute__;
706 # endif
707 # undef __rtld_global_attribute__
708 #endif
709 #undef EXTERN
710
711 #ifndef SHARED
712 /* dl-support.c defines these and initializes them early on. */
713 extern const ElfW(Phdr) *_dl_phdr;
714 extern size_t _dl_phnum;
715 #endif
716
717 #if PTHREAD_IN_LIBC
718 /* This function changes the permissions of all stacks (not just those
719 of the main stack). */
720 int _dl_make_stacks_executable (void **stack_endp) attribute_hidden;
721 #else
722 /* This is the initial value of GL(dl_make_stack_executable_hook).
723 A threads library can change it. The ld.so implementation changes
724 the permissions of the main stack only. */
725 extern int _dl_make_stack_executable (void **stack_endp);
726 rtld_hidden_proto (_dl_make_stack_executable)
727 #endif
728
729 /* Variable pointing to the end of the stack (or close to it). This value
730 must be constant over the runtime of the application. Some programs
731 might use the variable which results in copy relocations on some
732 platforms. But this does not matter, ld.so can always use the local
733 copy. */
734 extern void *__libc_stack_end
735 #ifndef LIBC_STACK_END_NOT_RELRO
736 attribute_relro
737 #endif
738 ;
739 rtld_hidden_proto (__libc_stack_end)
740
741 /* Parameters passed to the dynamic linker. */
742 extern int _dl_argc attribute_hidden attribute_relro;
743 extern char **_dl_argv attribute_relro;
744 rtld_hidden_proto (_dl_argv)
745 #define rtld_progname _dl_argv[0]
746
747 /* Flag set at startup and cleared when the last initializer has run. */
748 extern int _dl_starting_up;
749 weak_extern (_dl_starting_up)
750 rtld_hidden_proto (_dl_starting_up)
751
752 /* Random data provided by the kernel. */
753 extern void *_dl_random attribute_hidden attribute_relro;
754
755 /* Write message on the debug file descriptor. The parameters are
756 interpreted as for a `printf' call. All the lines start with a
757 tag showing the PID. */
758 extern void _dl_debug_printf (const char *fmt, ...)
759 __attribute__ ((__format__ (__printf__, 1, 2))) attribute_hidden;
760
761 /* Write message on the debug file descriptor. The parameters are
762 interpreted as for a `printf' call. All the lines buf the first
763 start with a tag showing the PID. */
764 extern void _dl_debug_printf_c (const char *fmt, ...)
765 __attribute__ ((__format__ (__printf__, 1, 2))) attribute_hidden;
766
767
768 /* Write a message on the specified descriptor FD. The parameters are
769 interpreted as for a `printf' call. */
770 extern void _dl_dprintf (int fd, const char *fmt, ...)
771 __attribute__ ((__format__ (__printf__, 2, 3)))
772 attribute_hidden;
773
774 /* Write LENGTH bytes at BUFFER to FD, like write. Returns the number
775 of bytes written on success, or a negative error constant on
776 failure. */
777 ssize_t _dl_write (int fd, const void *buffer, size_t length)
778 attribute_hidden;
779
780 /* Write a message on the specified descriptor standard output. The
781 parameters are interpreted as for a `printf' call. */
782 void _dl_printf (const char *fmt, ...)
783 attribute_hidden __attribute__ ((__format__ (__printf__, 1, 2)));
784
785 /* Write a message on the specified descriptor standard error. The
786 parameters are interpreted as for a `printf' call. */
787 void _dl_error_printf (const char *fmt, ...)
788 attribute_hidden __attribute__ ((__format__ (__printf__, 1, 2)));
789
790 /* Write a message on the specified descriptor standard error and exit
791 the program. The parameters are interpreted as for a `printf' call. */
792 void _dl_fatal_printf (const char *fmt, ...)
793 __attribute__ ((__format__ (__printf__, 1, 2), __noreturn__));
794 rtld_hidden_proto (_dl_fatal_printf)
795
796 /* An exception raised by the _dl_signal_error function family and
797 caught by _dl_catch_error function family. Exceptions themselves
798 are copied as part of the raise operation, but the strings are
799 not. */
800 struct dl_exception
801 {
802 const char *objname;
803 const char *errstring;
804
805 /* This buffer typically stores both objname and errstring
806 above. */
807 char *message_buffer;
808 };
809
810 /* Creates a new exception. This calls malloc; if allocation fails,
811 dummy values are inserted. OBJECT is the name of the problematical
812 shared object, or null if its a general problem. ERRSTRING is a
813 string describing the specific problem. */
814 void _dl_exception_create (struct dl_exception *, const char *object,
815 const char *errstring)
816 __attribute__ ((nonnull (1, 3)));
817 rtld_hidden_proto (_dl_exception_create)
818
819 /* Used internally to implement dlerror message freeing. See
820 include/dlfcn.h and dlfcn/dlerror.c. */
821 void _dl_error_free (void *ptr) attribute_hidden;
822
823 /* Like _dl_exception_create, but create errstring from a format
824 string FMT. Currently, only "%s" and "%%" are supported as format
825 directives. */
826 void _dl_exception_create_format (struct dl_exception *, const char *objname,
827 const char *fmt, ...)
828 __attribute__ ((nonnull (1, 3), format (printf, 3, 4)));
829 rtld_hidden_proto (_dl_exception_create_format)
830
831 /* Deallocate the exception, freeing allocated buffers (if
832 possible). */
833 void _dl_exception_free (struct dl_exception *)
834 __attribute__ ((nonnull (1)));
835 rtld_hidden_proto (_dl_exception_free)
836
837 /* This function is called by all the internal dynamic linker
838 functions when they encounter an error. ERRCODE is either an
839 `errno' code or zero; it specifies the return value of
840 _dl_catch_error. OCCASION is included in the error message if the
841 process is terminated immediately. */
842 void _dl_signal_exception (int errcode, struct dl_exception *,
843 const char *occasion)
844 __attribute__ ((__noreturn__));
845 rtld_hidden_proto (_dl_signal_exception)
846
847 /* Like _dl_signal_exception, but creates the exception first. */
848 extern void _dl_signal_error (int errcode, const char *object,
849 const char *occasion, const char *errstring)
850 __attribute__ ((__noreturn__));
851 rtld_hidden_proto (_dl_signal_error)
852
853 /* Like _dl_signal_exception, but may return when called in the
854 context of _dl_receive_error. This is only used during ld.so
855 bootstrap. In static and profiled builds, this is equivalent to
856 _dl_signal_exception. */
857 #if IS_IN (rtld)
858 extern void _dl_signal_cexception (int errcode, struct dl_exception *,
859 const char *occasion) attribute_hidden;
860 #else
861 __attribute__ ((always_inline))
862 static inline void
863 _dl_signal_cexception (int errcode, struct dl_exception *exception,
864 const char *occasion)
865 {
866 _dl_signal_exception (errcode, exception, occasion);
867 }
868 #endif
869
870 /* See _dl_signal_cexception above. */
871 #if IS_IN (rtld)
872 extern void _dl_signal_cerror (int errcode, const char *object,
873 const char *occasion, const char *errstring)
874 attribute_hidden;
875 #else
876 __attribute__ ((always_inline))
877 static inline void
878 _dl_signal_cerror (int errcode, const char *object,
879 const char *occasion, const char *errstring)
880 {
881 _dl_signal_error (errcode, object, occasion, errstring);
882 }
883 #endif
884
885 /* Call OPERATE, receiving errors from `dl_signal_cerror'. Unlike
886 `_dl_catch_error' the operation is resumed after the OPERATE
887 function returns.
888 ARGS is passed as argument to OPERATE. */
889 extern void _dl_receive_error (receiver_fct fct, void (*operate) (void *),
890 void *args) attribute_hidden;
891
892 /* Call OPERATE, catching errors from `_dl_signal_error' and related
893 functions. If there is no error, *ERRSTRING is set to null. If
894 there is an error, *ERRSTRING is set to a string constructed from
895 the strings passed to _dl_signal_error, and the error code passed
896 is the return value and *OBJNAME is set to the object name which
897 experienced the problems. ERRSTRING if nonzero points to a
898 malloc'ed string which the caller has to free after use. ARGS is
899 passed as argument to OPERATE. MALLOCEDP is set to true only if
900 the returned string is allocated using the libc's malloc. */
901 extern int _dl_catch_error (const char **objname, const char **errstring,
902 bool *mallocedp, void (*operate) (void *),
903 void *args) attribute_hidden;
904
905 /* Call OPERATE (ARGS). If no error occurs, set *EXCEPTION to zero.
906 Otherwise, store a copy of the raised exception in *EXCEPTION,
907 which has to be freed by _dl_exception_free. As a special case, if
908 EXCEPTION is null, call OPERATE (ARGS) with exception handling
909 disabled (so that exceptions are fatal). */
910 int _dl_catch_exception (struct dl_exception *exception,
911 void (*operate) (void *), void *args);
912 rtld_hidden_proto (_dl_catch_exception)
913
914 /* Open the shared object NAME and map in its segments.
915 LOADER's DT_RPATH is used in searching for NAME.
916 If the object is already opened, returns its existing map. */
917 extern struct link_map *_dl_map_object (struct link_map *loader,
918 const char *name,
919 int type, int trace_mode, int mode,
920 Lmid_t nsid) attribute_hidden;
921
922 /* Call _dl_map_object on the dependencies of MAP, and set up
923 MAP->l_searchlist. PRELOADS points to a vector of NPRELOADS previously
924 loaded objects that will be inserted into MAP->l_searchlist after MAP
925 but before its dependencies. */
926 extern void _dl_map_object_deps (struct link_map *map,
927 struct link_map **preloads,
928 unsigned int npreloads, int trace_mode,
929 int open_mode)
930 attribute_hidden;
931
932 /* Cache the locations of MAP's hash table. */
933 extern void _dl_setup_hash (struct link_map *map) attribute_hidden;
934
935
936 /* Collect the directories in the search path for LOADER's dependencies.
937 The data structure is defined in <dlfcn.h>. If COUNTING is true,
938 SI->dls_cnt and SI->dls_size are set; if false, those must be as set
939 by a previous call with COUNTING set, and SI must point to SI->dls_size
940 bytes to be used in filling in the result. */
941 extern void _dl_rtld_di_serinfo (struct link_map *loader,
942 Dl_serinfo *si, bool counting);
943
944 /* Process PT_GNU_PROPERTY program header PH in module L after
945 PT_LOAD segments are mapped from file FD. */
946 void _dl_process_pt_gnu_property (struct link_map *l, int fd,
947 const ElfW(Phdr) *ph);
948
949
950 /* Search loaded objects' symbol tables for a definition of the symbol
951 referred to by UNDEF. *SYM is the symbol table entry containing the
952 reference; it is replaced with the defining symbol, and the base load
953 address of the defining object is returned. SYMBOL_SCOPE is a
954 null-terminated list of object scopes to search; each object's
955 l_searchlist (i.e. the segment of the dependency tree starting at that
956 object) is searched in turn. REFERENCE_NAME should name the object
957 containing the reference; it is used in error messages.
958 TYPE_CLASS describes the type of symbol we are looking for. */
959 enum
960 {
961 /* If necessary add dependency between user and provider object. */
962 DL_LOOKUP_ADD_DEPENDENCY = 1,
963 /* Return most recent version instead of default version for
964 unversioned lookup. */
965 DL_LOOKUP_RETURN_NEWEST = 2,
966 /* Set if dl_lookup* called with GSCOPE lock held. */
967 DL_LOOKUP_GSCOPE_LOCK = 4,
968 /* Set if dl_lookup is called for non-lazy relocation processing
969 from _dl_relocate_object in elf/dl-reloc.c. */
970 DL_LOOKUP_FOR_RELOCATE = 8,
971 };
972
973 /* Lookup versioned symbol. */
974 extern lookup_t _dl_lookup_symbol_x (const char *undef,
975 struct link_map *undef_map,
976 const ElfW(Sym) **sym,
977 struct r_scope_elem *symbol_scope[],
978 const struct r_found_version *version,
979 int type_class, int flags,
980 struct link_map *skip_map)
981 attribute_hidden;
982
983
984 /* Restricted version of _dl_lookup_symbol_x. Searches MAP (and only
985 MAP) for the symbol UNDEF_NAME, with GNU hash NEW_HASH (computed
986 with dl_new_hash), symbol version VERSION, and symbol version hash
987 VERSION_HASH (computed with _dl_elf_hash). Returns a pointer to
988 the symbol table entry in MAP on success, or NULL on failure. MAP
989 must have symbol versioning information, or otherwise the result is
990 undefined. */
991 const ElfW(Sym) *_dl_lookup_direct (struct link_map *map,
992 const char *undef_name,
993 uint32_t new_hash,
994 const char *version,
995 uint32_t version_hash) attribute_hidden;
996
997 /* Add the new link_map NEW to the end of the namespace list. */
998 extern void _dl_add_to_namespace_list (struct link_map *new, Lmid_t nsid)
999 attribute_hidden;
1000
1001 /* Allocate a `struct link_map' for a new object being loaded. */
1002 extern struct link_map *_dl_new_object (char *realname, const char *libname,
1003 int type, struct link_map *loader,
1004 int mode, Lmid_t nsid)
1005 attribute_hidden;
1006
1007 /* Relocate the given object (if it hasn't already been).
1008 SCOPE is passed to _dl_lookup_symbol in symbol lookups.
1009 If RTLD_LAZY is set in RELOC-MODE, don't relocate its PLT. */
1010 extern void _dl_relocate_object (struct link_map *map,
1011 struct r_scope_elem *scope[],
1012 int reloc_mode, int consider_profiling)
1013 attribute_hidden;
1014
1015 /* Protect PT_GNU_RELRO area. */
1016 extern void _dl_protect_relro (struct link_map *map) attribute_hidden;
1017
1018 /* Call _dl_signal_error with a message about an unhandled reloc type.
1019 TYPE is the result of ELFW(R_TYPE) (r_info), i.e. an R_<CPU>_* value.
1020 PLT is nonzero if this was a PLT reloc; it just affects the message. */
1021 extern void _dl_reloc_bad_type (struct link_map *map,
1022 unsigned int type, int plt)
1023 attribute_hidden __attribute__ ((__noreturn__));
1024
1025 /* Check the version dependencies of all objects available through
1026 MAP. If VERBOSE print some more diagnostics. */
1027 extern int _dl_check_all_versions (struct link_map *map, int verbose,
1028 int trace_mode) attribute_hidden;
1029
1030 /* Check the version dependencies for MAP. If VERBOSE print some more
1031 diagnostics. */
1032 extern int _dl_check_map_versions (struct link_map *map, int verbose,
1033 int trace_mode) attribute_hidden;
1034
1035 /* Initialize the object in SCOPE by calling the constructors with
1036 ARGC, ARGV, and ENV as the parameters. */
1037 extern void _dl_init (struct link_map *main_map, int argc, char **argv,
1038 char **env) attribute_hidden;
1039
1040 /* Call the finalizer functions of all shared objects whose
1041 initializer functions have completed. */
1042 extern void _dl_fini (void) attribute_hidden;
1043
1044 /* Invoke the DT_FINI_ARRAY and DT_FINI destructors for MAP, which
1045 must be a struct link_map *. Can be used as an argument to
1046 _dl_catch_exception. */
1047 void _dl_call_fini (void *map) attribute_hidden;
1048
1049 /* Sort array MAPS according to dependencies of the contained objects.
1050 If FORCE_FIRST, MAPS[0] keeps its place even if the dependencies
1051 say otherwise. */
1052 extern void _dl_sort_maps (struct link_map **maps, unsigned int nmaps,
1053 bool force_first, bool for_fini) attribute_hidden;
1054
1055 /* The dynamic linker calls this function before and having changing
1056 any shared object mappings. The `r_state' member of `struct r_debug'
1057 says what change is taking place. This function's address is
1058 the value of the `r_brk' member. */
1059 extern void _dl_debug_state (void);
1060 rtld_hidden_proto (_dl_debug_state)
1061
1062 /* Initialize `struct r_debug_extended' for the namespace NS. LDBASE
1063 is the run-time load address of the dynamic linker, to be put in the
1064 `r_ldbase' member. Return the address of the structure. */
1065 extern struct r_debug *_dl_debug_initialize (ElfW(Addr) ldbase, Lmid_t ns)
1066 attribute_hidden;
1067
1068 /* Update the `r_map' member and return the address of `struct r_debug'
1069 of the namespace NS. */
1070 extern struct r_debug *_dl_debug_update (Lmid_t ns) attribute_hidden;
1071
1072 /* Initialize the basic data structure for the search paths. SOURCE
1073 is either "LD_LIBRARY_PATH" or "--library-path".
1074 GLIBC_HWCAPS_PREPEND adds additional glibc-hwcaps subdirectories to
1075 search. GLIBC_HWCAPS_MASK is used to filter the built-in
1076 subdirectories if not NULL. */
1077 extern void _dl_init_paths (const char *library_path, const char *source,
1078 const char *glibc_hwcaps_prepend,
1079 const char *glibc_hwcaps_mask)
1080 attribute_hidden;
1081
1082 /* Gather the information needed to install the profiling tables and start
1083 the timers. */
1084 extern void _dl_start_profile (void) attribute_hidden;
1085
1086 /* The actual functions used to keep book on the calls. */
1087 extern void _dl_mcount (ElfW(Addr) frompc, ElfW(Addr) selfpc);
1088 rtld_hidden_proto (_dl_mcount)
1089
1090 /* This function is simply a wrapper around the _dl_mcount function
1091 which does not require a FROMPC parameter since this is the
1092 calling function. */
1093 extern void _dl_mcount_wrapper (void *selfpc);
1094
1095 /* Show the members of the auxiliary array passed up from the kernel. */
1096 extern void _dl_show_auxv (void) attribute_hidden;
1097
1098 /* Return all environment variables starting with `LD_', one after the
1099 other. */
1100 extern char *_dl_next_ld_env_entry (char ***position) attribute_hidden;
1101
1102 /* Return an array with the names of the important hardware
1103 capabilities. PREPEND is a colon-separated list of glibc-hwcaps
1104 directories to search first. MASK is a colon-separated list used
1105 to filter the built-in glibc-hwcaps subdirectories. The length of
1106 the array is written to *SZ, and the maximum of all strings length
1107 is written to *MAX_CAPSTRLEN. */
1108 const struct r_strlenpair *_dl_important_hwcaps (const char *prepend,
1109 const char *mask,
1110 size_t *sz,
1111 size_t *max_capstrlen)
1112 attribute_hidden;
1113
1114 /* Look up NAME in ld.so.cache and return the file name stored there,
1115 or null if none is found. Caller must free returned string. */
1116 extern char *_dl_load_cache_lookup (const char *name) attribute_hidden;
1117
1118 /* If the system does not support MAP_COPY we cannot leave the file open
1119 all the time since this would create problems when the file is replaced.
1120 Therefore we provide this function to close the file and open it again
1121 once needed. */
1122 extern void _dl_unload_cache (void) attribute_hidden;
1123
1124 /* System-dependent function to read a file's whole contents in the
1125 most convenient manner available. *SIZEP gets the size of the
1126 file. On error MAP_FAILED is returned. */
1127 extern void *_dl_sysdep_read_whole_file (const char *file, size_t *sizep,
1128 int prot) attribute_hidden;
1129
1130 /* System-specific function to do initial startup for the dynamic linker.
1131 After this, file access calls and getenv must work. This is responsible
1132 for setting __libc_enable_secure if we need to be secure (e.g. setuid),
1133 and for setting _dl_argc and _dl_argv, and then calling _dl_main. */
1134 extern ElfW(Addr) _dl_sysdep_start (void **start_argptr,
1135 void (*dl_main) (const ElfW(Phdr) *phdr,
1136 ElfW(Word) phnum,
1137 ElfW(Addr) *user_entry,
1138 ElfW(auxv_t) *auxv))
1139 attribute_hidden;
1140
1141 extern void _dl_sysdep_start_cleanup (void) attribute_hidden;
1142
1143
1144 /* Determine next available module ID and set the L l_tls_modid. */
1145 extern void _dl_assign_tls_modid (struct link_map *l) attribute_hidden;
1146
1147 /* Count the modules with TLS segments. */
1148 extern size_t _dl_count_modids (void) attribute_hidden;
1149
1150 /* Calculate offset of the TLS blocks in the static TLS block. */
1151 extern void _dl_determine_tlsoffset (void) attribute_hidden;
1152
1153 /* Calculate the size of the static TLS surplus, when the given
1154 number of audit modules are loaded. */
1155 void _dl_tls_static_surplus_init (size_t naudit) attribute_hidden;
1156
1157 /* This function is called very early from dl_main to set up TLS and
1158 other thread-related data structures. */
1159 void __tls_pre_init_tp (void) attribute_hidden;
1160
1161 /* This function is called after processor-specific initialization of
1162 the TCB and thread pointer via TLS_INIT_TP, to complete very early
1163 initialization of the thread library. */
1164 void __tls_init_tp (void) attribute_hidden;
1165
1166 #ifndef SHARED
1167 /* Set up the TCB for statically linked applications. This is called
1168 early during startup because we always use TLS (for errno and the
1169 stack protector, among other things). */
1170 void __libc_setup_tls (void);
1171
1172 # if ENABLE_STATIC_PIE
1173 /* Relocate static executable with PIE. */
1174 extern void _dl_relocate_static_pie (void) attribute_hidden;
1175
1176 /* Get a pointer to _dl_main_map. */
1177 extern struct link_map * _dl_get_dl_main_map (void)
1178 __attribute__ ((visibility ("hidden")));
1179 # else
1180 # define _dl_relocate_static_pie()
1181 # endif
1182 #endif
1183
1184 /* Perform early memory allocation, avoiding a TCB dependency.
1185 Terminate the process if allocation fails. May attempt to use
1186 brk. */
1187 void *_dl_early_allocate (size_t size) attribute_hidden;
1188
1189 /* Initialization of libpthread for statically linked applications.
1190 If libpthread is not linked in, this is an empty function. */
1191 void __pthread_initialize_minimal (void) weak_function;
1192
1193 /* Initialize the DSO sort algorithm to use. */
1194 extern void _dl_sort_maps_init (void) attribute_hidden;
1195
1196 /* Allocate memory for static TLS block (unless MEM is nonzero) and dtv. */
1197 extern void *_dl_allocate_tls (void *mem);
1198 rtld_hidden_proto (_dl_allocate_tls)
1199
1200 /* Get size and alignment requirements of the static TLS block. */
1201 extern void _dl_get_tls_static_info (size_t *sizep, size_t *alignp);
1202
1203 extern void _dl_allocate_static_tls (struct link_map *map) attribute_hidden;
1204
1205 /* These are internal entry points to the two halves of _dl_allocate_tls,
1206 only used within rtld.c itself at startup time. */
1207 extern void *_dl_allocate_tls_storage (void) attribute_hidden;
1208 extern void *_dl_allocate_tls_init (void *, bool);
1209 rtld_hidden_proto (_dl_allocate_tls_init)
1210
1211 /* True if the TCB has been set up. */
1212 extern bool __rtld_tls_init_tp_called attribute_hidden;
1213
1214 /* Deallocate memory allocated with _dl_allocate_tls. */
1215 extern void _dl_deallocate_tls (void *tcb, bool dealloc_tcb);
1216 rtld_hidden_proto (_dl_deallocate_tls)
1217
1218 extern void _dl_nothread_init_static_tls (struct link_map *) attribute_hidden;
1219
1220 /* Find origin of the executable. */
1221 extern const char *_dl_get_origin (void) attribute_hidden;
1222
1223 /* Count DSTs. */
1224 extern size_t _dl_dst_count (const char *name) attribute_hidden;
1225
1226 /* Substitute DST values. */
1227 extern char *_dl_dst_substitute (struct link_map *l, const char *name,
1228 char *result) attribute_hidden;
1229
1230 /* Open the shared object NAME, relocate it, and run its initializer if it
1231 hasn't already been run. MODE is as for `dlopen' (see <dlfcn.h>). If
1232 the object is already opened, returns its existing map. */
1233 extern void *_dl_open (const char *name, int mode, const void *caller,
1234 Lmid_t nsid, int argc, char *argv[], char *env[])
1235 attribute_hidden;
1236
1237 /* Free or queue for freeing scope OLD. If other threads might be
1238 in the middle of _dl_fixup, _dl_profile_fixup or dl*sym using the
1239 old scope, OLD can't be freed until no thread is using it. */
1240 extern int _dl_scope_free (void *) attribute_hidden;
1241
1242
1243 /* Add module to slot information data. If DO_ADD is false, only the
1244 required memory is allocated. Must be called with GL
1245 (dl_load_tls_lock) acquired. If the function has already been called
1246 for the link map L with !do_add, then this function will not raise
1247 an exception, otherwise it is possible that it encounters a memory
1248 allocation failure. */
1249 extern void _dl_add_to_slotinfo (struct link_map *l, bool do_add)
1250 attribute_hidden;
1251
1252 /* Update slot information data for at least the generation of the
1253 module with the given index. */
1254 extern struct link_map *_dl_update_slotinfo (unsigned long int req_modid)
1255 attribute_hidden;
1256
1257 /* Look up the module's TLS block as for __tls_get_addr,
1258 but never touch anything. Return null if it's not allocated yet. */
1259 extern void *_dl_tls_get_addr_soft (struct link_map *l) attribute_hidden;
1260
1261 extern int _dl_addr_inside_object (struct link_map *l, const ElfW(Addr) addr)
1262 attribute_hidden;
1263
1264 /* Show show of an object. */
1265 extern void _dl_show_scope (struct link_map *new, int from)
1266 attribute_hidden;
1267
1268 extern struct link_map *_dl_find_dso_for_object (const ElfW(Addr) addr);
1269 rtld_hidden_proto (_dl_find_dso_for_object)
1270
1271 /* Initialization which is normally done by the dynamic linker. */
1272 extern void _dl_non_dynamic_init (void)
1273 attribute_hidden;
1274
1275 /* Used by static binaries to check the auxiliary vector. */
1276 extern void _dl_aux_init (ElfW(auxv_t) *av)
1277 attribute_hidden;
1278
1279 /* Initialize the static TLS space for the link map in all existing
1280 threads. */
1281 #if PTHREAD_IN_LIBC
1282 void _dl_init_static_tls (struct link_map *map) attribute_hidden;
1283 #endif
1284 static inline void
1285 dl_init_static_tls (struct link_map *map)
1286 {
1287 #if PTHREAD_IN_LIBC
1288 /* The stack list is available to ld.so, so the initialization can
1289 be handled within ld.so directly. */
1290 _dl_init_static_tls (map);
1291 #else
1292 GL (dl_init_static_tls) (map);
1293 #endif
1294 }
1295
1296 #ifndef SHARED
1297 /* Called before relocating ld.so during static dlopen. This can be
1298 used to partly initialize the dormant ld.so copy in the static
1299 dlopen namespace. */
1300 void __rtld_static_init (struct link_map *map) attribute_hidden;
1301 #endif
1302
1303 /* Return true if the ld.so copy in this namespace is actually active
1304 and working. If false, the dl_open/dlfcn hooks have to be used to
1305 call into the outer dynamic linker (which happens after static
1306 dlopen). */
1307 #ifdef SHARED
1308 static inline bool
1309 rtld_active (void)
1310 {
1311 /* The default-initialized variable does not have a non-zero
1312 dl_init_all_dirs member, so this allows us to recognize an
1313 initialized and active ld.so copy. */
1314 return GLRO(dl_init_all_dirs) != NULL;
1315 }
1316
1317 static inline struct auditstate *
1318 link_map_audit_state (struct link_map *l, size_t index)
1319 {
1320 if (l == &GL (dl_rtld_map))
1321 /* The auditstate array is stored separately. */
1322 return &GL (dl_rtld_auditstate) [index];
1323 else
1324 {
1325 /* The auditstate array follows the link map in memory. */
1326 struct auditstate *base = (struct auditstate *) (l + 1);
1327 return &base[index];
1328 }
1329 }
1330
1331 /* Call the la_objsearch from the audit modules from the link map L. If
1332 ORIGNAME is non NULL, it is updated with the revious name prior calling
1333 la_objsearch. */
1334 const char *_dl_audit_objsearch (const char *name, struct link_map *l,
1335 unsigned int code)
1336 attribute_hidden;
1337
1338 /* Call the la_activity from the audit modules from the link map L and issues
1339 the ACTION argument. */
1340 void _dl_audit_activity_map (struct link_map *l, int action)
1341 attribute_hidden;
1342
1343 /* Call the la_activity from the audit modules from the link map from the
1344 namespace NSID and issues the ACTION argument. */
1345 void _dl_audit_activity_nsid (Lmid_t nsid, int action)
1346 attribute_hidden;
1347
1348 /* Call the la_objopen from the audit modules for the link_map L on the
1349 namespace identification NSID. */
1350 void _dl_audit_objopen (struct link_map *l, Lmid_t nsid)
1351 attribute_hidden;
1352
1353 /* Call the la_objclose from the audit modules for the link_map L. */
1354 void _dl_audit_objclose (struct link_map *l)
1355 attribute_hidden;
1356
1357 /* Call the la_preinit from the audit modules for the link_map L. */
1358 void _dl_audit_preinit (struct link_map *l);
1359
1360 /* Call the la_symbind{32,64} from the audit modules for the link_map L. If
1361 RELOC_RESULT is NULL it assumes the symbol to be bind-now and will set
1362 the flags with LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT prior calling
1363 la_symbind{32,64}. */
1364 void _dl_audit_symbind (struct link_map *l, struct reloc_result *reloc_result,
1365 const void *reloc, const ElfW(Sym) *defsym,
1366 DL_FIXUP_VALUE_TYPE *value, lookup_t result, bool lazy)
1367 attribute_hidden;
1368 /* Same as _dl_audit_symbind, but also sets LA_SYMB_DLSYM flag. */
1369 void _dl_audit_symbind_alt (struct link_map *l, const ElfW(Sym) *ref,
1370 void **value, lookup_t result);
1371 rtld_hidden_proto (_dl_audit_symbind_alt)
1372 void _dl_audit_pltenter (struct link_map *l, struct reloc_result *reloc_result,
1373 DL_FIXUP_VALUE_TYPE *value, void *regs,
1374 long int *framesize)
1375 attribute_hidden;
1376 void DL_ARCH_FIXUP_ATTRIBUTE _dl_audit_pltexit (struct link_map *l,
1377 ElfW(Word) reloc_arg,
1378 const void *inregs,
1379 void *outregs)
1380 attribute_hidden;
1381 #endif /* SHARED */
1382
1383 #if PTHREAD_IN_LIBC && defined SHARED
1384 /* Recursive locking implementation for use within the dynamic loader.
1385 Used to define the __rtld_lock_lock_recursive and
1386 __rtld_lock_unlock_recursive via <libc-lock.h>. Initialized to a
1387 no-op dummy implementation early. Similar
1388 to GL (dl_rtld_lock_recursive) and GL (dl_rtld_unlock_recursive)
1389 in !PTHREAD_IN_LIBC builds. */
1390 extern int (*___rtld_mutex_lock) (pthread_mutex_t *) attribute_hidden;
1391 extern int (*___rtld_mutex_unlock) (pthread_mutex_t *lock) attribute_hidden;
1392
1393 /* Called after libc has been loaded, but before RELRO is activated.
1394 Used to initialize the function pointers to the actual
1395 implementations. */
1396 void __rtld_mutex_init (void) attribute_hidden;
1397 #else /* !PTHREAD_IN_LIBC */
1398 static inline void
1399 __rtld_mutex_init (void)
1400 {
1401 /* The initialization happens later (!PTHREAD_IN_LIBC) or is not
1402 needed at all (!SHARED). */
1403 }
1404 #endif /* !PTHREAD_IN_LIBC */
1405
1406 /* Implementation of GL (dl_libc_freeres). */
1407 void __rtld_libc_freeres (void) attribute_hidden;
1408
1409 void __thread_gscope_wait (void) attribute_hidden;
1410 # define THREAD_GSCOPE_WAIT() __thread_gscope_wait ()
1411
1412 __END_DECLS
1413
1414 #endif /* ldsodefs.h */