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 <tls.h>
42#include <list_t.h>
43
44__BEGIN_DECLS
45
46#define VERSYMIDX(sym) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGIDX (sym))
47#define VALIDX(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM \
48 + DT_EXTRANUM + DT_VALTAGIDX (tag))
49#define ADDRIDX(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM \
50 + DT_EXTRANUM + DT_VALNUM + DT_ADDRTAGIDX (tag))
51
52/* Type of GNU hash which the machine uses. */
53#ifndef ELF_MACHINE_GNU_HASH_ADDRIDX
54# define ELF_MACHINE_GNU_HASH_ADDRIDX ADDRIDX (DT_GNU_HASH)
55#endif
56
57/* Calculate the index of a symbol in GNU hash. */
58#ifndef ELF_MACHINE_HASH_SYMIDX
59# define ELF_MACHINE_HASH_SYMIDX(map, hasharr) \
60 ((hasharr) - (map)->l_gnu_chain_zero)
61#endif
62
63/* Setup MIPS xhash. Defined only for MIPS. */
64#ifndef ELF_MACHINE_XHASH_SETUP
65# define ELF_MACHINE_XHASH_SETUP(hash32, symbias, map) \
66 ((void) (hash32), (void) (symbias), (void) (map))
67#endif
68
69/* We use this macro to refer to ELF types independent of the native wordsize.
70 `ElfW(TYPE)' is used in place of `Elf32_TYPE' or `Elf64_TYPE'. */
71#define ELFW(type) _ElfW (ELF, __ELF_NATIVE_CLASS, type)
72
73/* Return true if dynamic section in the shared library L should be
74 relocated. */
75
76static inline bool
77dl_relocate_ld (const struct link_map *l)
78{
79 /* Don't relocate dynamic section if it is readonly */
80 return !(l->l_ld_readonly || DL_RO_DYN_SECTION);
81}
82
83/* All references to the value of l_info[DT_PLTGOT],
84 l_info[DT_STRTAB], l_info[DT_SYMTAB], l_info[DT_RELA],
85 l_info[DT_REL], l_info[DT_JMPREL], and l_info[VERSYMIDX (DT_VERSYM)]
86 have to be accessed via the D_PTR macro. The macro is needed since for
87 most architectures the entry is already relocated - but for some not
88 and we need to relocate at access time. */
89#define D_PTR(map, i) \
90 ((map)->i->d_un.d_ptr + (dl_relocate_ld (map) ? 0 : (map)->l_addr))
91
92/* Result of the lookup functions and how to retrieve the base address. */
93typedef struct link_map *lookup_t;
94#define LOOKUP_VALUE(map) map
95#define LOOKUP_VALUE_ADDRESS(map, set) ((set) || (map) ? (map)->l_addr : 0)
96
97/* Calculate the address of symbol REF using the base address from map MAP,
98 if non-NULL. Don't check for NULL map if MAP_SET is TRUE. */
99#define SYMBOL_ADDRESS(map, ref, map_set) \
100 ((ref) == NULL ? 0 \
101 : (__glibc_unlikely ((ref)->st_shndx == SHN_ABS) ? 0 \
102 : LOOKUP_VALUE_ADDRESS (map, map_set)) + (ref)->st_value)
103
104/* Type of a constructor function, in DT_INIT, DT_INIT_ARRAY,
105 DT_PREINIT_ARRAY. */
106typedef void (*dl_init_t) (int, char **, char **);
107
108/* Type of a constructor function, in DT_FINI, DT_FINI_ARRAY. */
109typedef void (*fini_t) (void);
110
111/* On some architectures a pointer to a function is not just a pointer
112 to the actual code of the function but rather an architecture
113 specific descriptor. */
114#ifndef ELF_FUNCTION_PTR_IS_SPECIAL
115# define DL_SYMBOL_ADDRESS(map, ref) \
116 (void *) SYMBOL_ADDRESS (map, ref, false)
117# define DL_LOOKUP_ADDRESS(addr) ((ElfW(Addr)) (addr))
118# define DL_CALL_DT_INIT(map, start, argc, argv, env) \
119 ((dl_init_t) (start)) (argc, argv, env)
120# define DL_CALL_DT_FINI(map, start) ((fini_t) (start)) ()
121#endif
122
123/* On some architectures dladdr can't use st_size of all symbols this way. */
124#define DL_ADDR_SYM_MATCH(L, SYM, MATCHSYM, ADDR) \
125 ((ADDR) >= (L)->l_addr + (SYM)->st_value \
126 && ((((SYM)->st_shndx == SHN_UNDEF || (SYM)->st_size == 0) \
127 && (ADDR) == (L)->l_addr + (SYM)->st_value) \
128 || (ADDR) < (L)->l_addr + (SYM)->st_value + (SYM)->st_size) \
129 && ((MATCHSYM) == NULL || (MATCHSYM)->st_value < (SYM)->st_value))
130
131/* According to the ELF gABI no STV_HIDDEN or STV_INTERNAL symbols are
132 expected to be present in dynamic symbol tables as they should have
133 been either removed or converted to STB_LOCAL binding by the static
134 linker. However some GNU binutils versions produce such symbols in
135 some cases. To prevent such symbols present in a buggy binary from
136 preempting global symbols we filter them out with this predicate. */
137static __always_inline bool
138dl_symbol_visibility_binds_local_p (const ElfW(Sym) *sym)
139{
140 return (ELFW(ST_VISIBILITY) (sym->st_other) == STV_HIDDEN
141 || ELFW(ST_VISIBILITY) (sym->st_other) == STV_INTERNAL);
142}
143
144/* Unmap a loaded object, called by _dl_close (). */
145#ifndef DL_UNMAP_IS_SPECIAL
146# define DL_UNMAP(map) _dl_unmap_segments (map)
147#endif
148
149/* Reloc type classes as returned by elf_machine_type_class().
150 ELF_RTYPE_CLASS_PLT means this reloc should not be satisfied by
151 some PLT symbol, ELF_RTYPE_CLASS_COPY means this reloc should not be
152 satisfied by any symbol in the executable. Some architectures do
153 not support copy relocations. In this case we define the macro to
154 zero so that the code for handling them gets automatically optimized
155 out. */
156#define ELF_RTYPE_CLASS_PLT 1
157#ifndef DL_NO_COPY_RELOCS
158# define ELF_RTYPE_CLASS_COPY 2
159#else
160# define ELF_RTYPE_CLASS_COPY 0
161#endif
162
163/* ELF uses the PF_x macros to specify the segment permissions, mmap
164 uses PROT_xxx. In most cases the three macros have the values 1, 2,
165 and 3 but not in a matching order. The following macros allows
166 converting from the PF_x values to PROT_xxx values. */
167#define PF_TO_PROT \
168 ((PROT_READ << (PF_R * 4)) \
169 | (PROT_WRITE << (PF_W * 4)) \
170 | (PROT_EXEC << (PF_X * 4)) \
171 | ((PROT_READ | PROT_WRITE) << ((PF_R | PF_W) * 4)) \
172 | ((PROT_READ | PROT_EXEC) << ((PF_R | PF_X) * 4)) \
173 | ((PROT_WRITE | PROT_EXEC) << (PF_W | PF_X) * 4) \
174 | ((PROT_READ | PROT_WRITE | PROT_EXEC) << ((PF_R | PF_W | PF_X) * 4)))
175
176/* The filename itself, or the main program name, if available. */
177#define DSO_FILENAME(name) ((name)[0] ? (name) \
178 : (rtld_progname ?: "<main program>"))
179
180#define RTLD_PROGNAME (rtld_progname ?: "<program name unknown>")
181
182/* For the version handling we need an array with only names and their
183 hash values. */
184struct r_found_version
185 {
186 const char *name;
187 ElfW(Word) hash;
188
189 int hidden;
190 const char *filename;
191 };
192
193/* We want to cache information about the searches for shared objects. */
194
195enum r_dir_status { unknown, nonexisting, existing };
196
197struct r_search_path_elem
198 {
199 /* This link is only used in the `all_dirs' member of `r_search_path'. */
200 struct r_search_path_elem *next;
201
202 /* Strings saying where the definition came from. */
203 const char *what;
204 const char *where;
205
206 /* Basename for this search path element. The string must end with
207 a slash character. */
208 const char *dirname;
209 size_t dirnamelen;
210
211 enum r_dir_status status[0];
212 };
213
214struct r_strlenpair
215 {
216 const char *str;
217 size_t len;
218 };
219
220
221/* A data structure for a simple single linked list of strings. */
222struct libname_list
223 {
224 const char *name; /* Name requested (before search). */
225 struct libname_list *next; /* Link to next name for this object. */
226 int dont_free; /* Flag whether this element should be freed
227 if the object is not entirely unloaded. */
228 };
229
230
231/* DSO sort algorithm to use (check dl-sort-maps.c). */
232enum dso_sort_algorithm
233 {
234 dso_sort_algorithm_original,
235 dso_sort_algorithm_dfs
236 };
237
238struct audit_ifaces
239{
240 void (*activity) (uintptr_t *, unsigned int);
241 char *(*objsearch) (const char *, uintptr_t *, unsigned int);
242 unsigned int (*objopen) (struct link_map *, Lmid_t, uintptr_t *);
243 void (*preinit) (uintptr_t *);
244 union
245 {
246 uintptr_t (*symbind32) (Elf32_Sym *, unsigned int, uintptr_t *,
247 uintptr_t *, unsigned int *, const char *);
248 uintptr_t (*symbind64) (Elf64_Sym *, unsigned int, uintptr_t *,
249 uintptr_t *, unsigned int *, const char *);
250 };
251 union
252 {
253#ifdef ARCH_PLTENTER_MEMBERS
254 ARCH_PLTENTER_MEMBERS;
255#endif
256 };
257 union
258 {
259#ifdef ARCH_PLTEXIT_MEMBERS
260 ARCH_PLTEXIT_MEMBERS;
261#endif
262 };
263 unsigned int (*objclose) (uintptr_t *);
264
265 struct audit_ifaces *next;
266};
267
268
269/* Test whether given NAME matches any of the names of the given object. */
270extern int _dl_name_match_p (const char *__name, const struct link_map *__map)
271 attribute_hidden;
272
273/* Compute next higher prime number. */
274extern unsigned long int _dl_higher_prime_number (unsigned long int n)
275 attribute_hidden;
276
277/* A stripped down strtoul-like implementation. */
278uint64_t _dl_strtoul (const char *, char **) attribute_hidden;
279
280/* Function used as argument for `_dl_receive_error' function. The
281 arguments are the error code, error string, and the objname the
282 error occurred in. */
283typedef void (*receiver_fct) (int, const char *, const char *);
284
285/* Internal functions of the run-time dynamic linker.
286 These can be accessed if you link again the dynamic linker
287 as a shared library, as in `-lld' or `/lib/ld.so' explicitly;
288 but are not normally of interest to user programs.
289
290 The `-ldl' library functions in <dlfcn.h> provide a simple
291 user interface to run-time dynamic linking. */
292
293
294#ifndef SHARED
295# define EXTERN extern
296# define GL(name) _##name
297#else
298# define EXTERN
299# if IS_IN (rtld)
300# define GL(name) _rtld_local._##name
301# else
302# define GL(name) _rtld_global._##name
303# endif
304struct rtld_global
305{
306#endif
307 /* Don't change the order of the following elements. 'dl_loaded'
308 must remain the first element. Forever. */
309
310/* Non-shared code has no support for multiple namespaces. */
311#ifdef SHARED
312# define DL_NNS 16
313#else
314# define DL_NNS 1
315#endif
316 EXTERN struct link_namespaces
317 {
318 /* A pointer to the map for the main map. */
319 struct link_map *_ns_loaded;
320 /* Number of object in the _dl_loaded list. */
321 unsigned int _ns_nloaded;
322 /* Direct pointer to the searchlist of the main object. */
323 struct r_scope_elem *_ns_main_searchlist;
324 /* This is zero at program start to signal that the global scope map is
325 allocated by rtld. Later it keeps the size of the map. It might be
326 reset if in _dl_close if the last global object is removed. */
327 unsigned int _ns_global_scope_alloc;
328
329 /* During dlopen, this is the number of objects that still need to
330 be added to the global scope map. It has to be taken into
331 account when resizing the map, for future map additions after
332 recursive dlopen calls from ELF constructors. */
333 unsigned int _ns_global_scope_pending_adds;
334
335 /* Once libc.so has been loaded into the namespace, this points to
336 its link map. */
337 struct link_map *libc_map;
338
339 /* Search table for unique objects. */
340 struct unique_sym_table
341 {
342 __rtld_lock_define_recursive (, lock)
343 struct unique_sym
344 {
345 uint32_t hashval;
346 const char *name;
347 const ElfW(Sym) *sym;
348 const struct link_map *map;
349 } *entries;
350 size_t size;
351 size_t n_elements;
352 void (*free) (void *);
353 } _ns_unique_sym_table;
354 /* Keep track of changes to each namespace' list. */
355 struct r_debug_extended _ns_debug;
356 } _dl_ns[DL_NNS];
357 /* One higher than index of last used namespace. */
358 EXTERN size_t _dl_nns;
359
360 /* During the program run we must not modify the global data of
361 loaded shared object simultanously in two threads. Therefore we
362 protect `_dl_open' and `_dl_close' in dl-close.c.
363
364 This must be a recursive lock since the initializer function of
365 the loaded object might as well require a call to this function.
366 At this time it is not anymore a problem to modify the tables. */
367 __rtld_lock_define_recursive (EXTERN, _dl_load_lock)
368 /* This lock is used to keep __dl_iterate_phdr from inspecting the
369 list of loaded objects while an object is added to or removed
370 from that list. */
371 __rtld_lock_define_recursive (EXTERN, _dl_load_write_lock)
372 /* This lock protects global and module specific TLS related data.
373 E.g. it is held in dlopen and dlclose when GL(dl_tls_generation),
374 GL(dl_tls_max_dtv_idx) or GL(dl_tls_dtv_slotinfo_list) are
375 accessed and when TLS related relocations are processed for a
376 module. It was introduced to keep pthread_create accessing TLS
377 state that is being set up. */
378 __rtld_lock_define_recursive (EXTERN, _dl_load_tls_lock)
379
380 /* Incremented whenever something may have been added to dl_loaded. */
381 EXTERN unsigned long long _dl_load_adds;
382
383 /* The object to be initialized first. */
384 EXTERN struct link_map *_dl_initfirst;
385
386 /* Map of shared object to be profiled. */
387 EXTERN struct link_map *_dl_profile_map;
388
389 /* Counters for the number of relocations performed. */
390 EXTERN unsigned long int _dl_num_relocations;
391 EXTERN unsigned long int _dl_num_cache_relocations;
392
393 /* List of search directories. */
394 EXTERN struct r_search_path_elem *_dl_all_dirs;
395
396 /* Structure describing the dynamic linker itself. */
397 EXTERN struct link_map _dl_rtld_map;
398#ifdef SHARED
399 /* Used to store the audit information for the link map of the
400 dynamic loader. */
401 struct auditstate _dl_rtld_auditstate[DL_NNS];
402#endif
403
404#if !PTHREAD_IN_LIBC && defined SHARED \
405 && defined __rtld_lock_default_lock_recursive
406 EXTERN void (*_dl_rtld_lock_recursive) (void *);
407 EXTERN void (*_dl_rtld_unlock_recursive) (void *);
408#endif
409
410 /* Get architecture specific definitions. */
411#define PROCINFO_DECL
412#ifndef PROCINFO_CLASS
413# define PROCINFO_CLASS EXTERN
414#endif
415#include <dl-procruntime.c>
416
417#if !PTHREAD_IN_LIBC
418 /* If loading a shared object requires that we make the stack executable
419 when it was not, we do it by calling this function.
420 It returns an errno code or zero on success. */
421 EXTERN int (*_dl_make_stack_executable_hook) (void **);
422#endif
423
424 /* Prevailing state of the stack, PF_X indicating it's executable. */
425 EXTERN ElfW(Word) _dl_stack_flags;
426
427 /* Flag signalling whether there are gaps in the module ID allocation. */
428 EXTERN bool _dl_tls_dtv_gaps;
429 /* Highest dtv index currently needed. */
430 EXTERN size_t _dl_tls_max_dtv_idx;
431 /* Information about the dtv slots. */
432 EXTERN struct dtv_slotinfo_list
433 {
434 size_t len;
435 struct dtv_slotinfo_list *next;
436 struct dtv_slotinfo
437 {
438 size_t gen;
439 struct link_map *map;
440 } slotinfo[];
441 } *_dl_tls_dtv_slotinfo_list;
442 /* Number of modules in the static TLS block. */
443 EXTERN size_t _dl_tls_static_nelem;
444 /* Size actually allocated in the static TLS block. */
445 EXTERN size_t _dl_tls_static_used;
446 /* Remaining amount of static TLS that may be used for optimizing
447 dynamic TLS access (e.g. with TLSDESC). */
448 EXTERN size_t _dl_tls_static_optional;
449
450/* Number of additional entries in the slotinfo array of each slotinfo
451 list element. A large number makes it almost certain take we never
452 have to iterate beyond the first element in the slotinfo list. */
453#define TLS_SLOTINFO_SURPLUS (62)
454
455/* Number of additional slots in the dtv allocated. */
456#define DTV_SURPLUS (14)
457
458 /* Initial dtv of the main thread, not allocated with normal malloc. */
459 EXTERN void *_dl_initial_dtv;
460 /* Generation counter for the dtv. */
461 EXTERN size_t _dl_tls_generation;
462
463#if !PTHREAD_IN_LIBC
464 EXTERN void (*_dl_init_static_tls) (struct link_map *);
465#endif
466
467 /* Scopes to free after next THREAD_GSCOPE_WAIT (). */
468 EXTERN struct dl_scope_free_list
469 {
470 size_t count;
471 void *list[50];
472 } *_dl_scope_free_list;
473#if PTHREAD_IN_LIBC
474 /* List of active thread stacks, with memory managed by glibc. */
475 EXTERN list_t _dl_stack_used;
476
477 /* List of thread stacks that were allocated by the application. */
478 EXTERN list_t _dl_stack_user;
479
480 /* List of queued thread stacks. */
481 EXTERN list_t _dl_stack_cache;
482
483 /* Total size of all stacks in the cache (sum over stackblock_size). */
484 EXTERN size_t _dl_stack_cache_actsize;
485
486 /* We need to record what list operations we are going to do so
487 that, in case of an asynchronous interruption due to a fork()
488 call, we can correct for the work. */
489 EXTERN uintptr_t _dl_in_flight_stack;
490
491 /* Mutex protecting the stack lists. */
492 EXTERN int _dl_stack_cache_lock;
493#else
494 /* The total number of thread IDs currently in use, or on the list of
495 available thread IDs. */
496 EXTERN int _dl_pthread_num_threads;
497
498 /* Array of __pthread structures and its lock. */
499 EXTERN struct __pthread **_dl_pthread_threads;
500 __libc_rwlock_define (EXTERN, _dl_pthread_threads_lock)
501#endif
502#ifdef SHARED
503};
504# define __rtld_global_attribute__
505# if IS_IN (rtld)
506# ifdef HAVE_SDATA_SECTION
507# define __rtld_local_attribute__ \
508 __attribute__ ((visibility ("hidden"), section (".sdata")))
509# undef __rtld_global_attribute__
510# define __rtld_global_attribute__ __attribute__ ((section (".sdata")))
511# else
512# define __rtld_local_attribute__ __attribute__ ((visibility ("hidden")))
513# endif
514extern struct rtld_global _rtld_local __rtld_local_attribute__;
515# undef __rtld_local_attribute__
516# endif
517extern struct rtld_global _rtld_global __rtld_global_attribute__;
518# undef __rtld_global_attribute__
519#endif
520
521#ifndef SHARED
522# define GLRO(name) _##name
523#else
524# if IS_IN (rtld)
525# define GLRO(name) _rtld_local_ro._##name
526# else
527# define GLRO(name) _rtld_global_ro._##name
528# endif
529struct rtld_global_ro
530{
531#endif
532
533 /* If nonzero the appropriate debug information is printed. */
534 EXTERN int _dl_debug_mask;
535#define DL_DEBUG_LIBS (1 << 0)
536#define DL_DEBUG_IMPCALLS (1 << 1)
537#define DL_DEBUG_BINDINGS (1 << 2)
538#define DL_DEBUG_SYMBOLS (1 << 3)
539#define DL_DEBUG_VERSIONS (1 << 4)
540#define DL_DEBUG_RELOC (1 << 5)
541#define DL_DEBUG_FILES (1 << 6)
542#define DL_DEBUG_STATISTICS (1 << 7)
543#define DL_DEBUG_UNUSED (1 << 8)
544#define DL_DEBUG_SCOPES (1 << 9)
545/* These two are used only internally. */
546#define DL_DEBUG_HELP (1 << 10)
547
548 /* Platform name. */
549 EXTERN const char *_dl_platform;
550 EXTERN size_t _dl_platformlen;
551
552 /* Cached value of `getpagesize ()'. */
553 EXTERN size_t _dl_pagesize;
554
555 /* Cached value of `sysconf (_SC_MINSIGSTKSZ)'. */
556 EXTERN size_t _dl_minsigstacksize;
557
558 /* Do we read from ld.so.cache? */
559 EXTERN int _dl_inhibit_cache;
560
561 /* Copy of the content of `_dl_main_searchlist' at startup time. */
562 EXTERN struct r_scope_elem _dl_initial_searchlist;
563
564 /* CLK_TCK as reported by the kernel. */
565 EXTERN int _dl_clktck;
566
567 /* If nonzero print warnings messages. */
568 EXTERN int _dl_verbose;
569
570 /* File descriptor to write debug messages to. */
571 EXTERN int _dl_debug_fd;
572
573 /* Do we do lazy relocations? */
574 EXTERN int _dl_lazy;
575
576 /* Nonzero if runtime lookups should not update the .got/.plt. */
577 EXTERN int _dl_bind_not;
578
579 /* Nonzero if references should be treated as weak during runtime
580 linking. */
581 EXTERN int _dl_dynamic_weak;
582
583 /* Default floating-point control word. */
584 EXTERN fpu_control_t _dl_fpu_control;
585
586 /* Mask for hardware capabilities that are available. */
587 EXTERN uint64_t _dl_hwcap;
588
589#if !HAVE_TUNABLES
590 /* Mask for important hardware capabilities we honour. */
591 EXTERN uint64_t _dl_hwcap_mask;
592#endif
593
594#ifdef HAVE_AUX_VECTOR
595 /* Pointer to the auxv list supplied to the program at startup. */
596 EXTERN ElfW(auxv_t) *_dl_auxv;
597#endif
598
599 /* Get architecture specific definitions. */
600#include <dl-procinfo.c>
601
602 /* Names of shared object for which the RPATH should be ignored. */
603 EXTERN const char *_dl_inhibit_rpath;
604
605 /* Location of the binary. */
606 EXTERN const char *_dl_origin_path;
607
608 /* Size of the static TLS block. */
609 EXTERN size_t _dl_tls_static_size;
610
611 /* Alignment requirement of the static TLS block. */
612 EXTERN size_t _dl_tls_static_align;
613
614 /* Size of surplus space in the static TLS area for dynamically
615 loaded modules with IE-model TLS or for TLSDESC optimization.
616 See comments in elf/dl-tls.c where it is initialized. */
617 EXTERN size_t _dl_tls_static_surplus;
618
619 /* Name of the shared object to be profiled (if any). */
620 EXTERN const char *_dl_profile;
621 /* Filename of the output file. */
622 EXTERN const char *_dl_profile_output;
623
624 /* All search directories defined at startup. This is assigned a
625 non-NULL pointer by the ld.so startup code (after initialization
626 to NULL), so this can also serve as an indicator whether a copy
627 of ld.so is initialized and active. See the rtld_active function
628 below. */
629 EXTERN struct r_search_path_elem *_dl_init_all_dirs;
630
631#ifdef NEED_DL_SYSINFO
632 /* Syscall handling improvements. This is very specific to x86. */
633 EXTERN uintptr_t _dl_sysinfo;
634#endif
635
636#ifdef NEED_DL_SYSINFO_DSO
637 /* The vsyscall page is a virtual DSO pre-mapped by the kernel.
638 This points to its ELF header. */
639 EXTERN const ElfW(Ehdr) *_dl_sysinfo_dso;
640
641 /* At startup time we set up the normal DSO data structure for it,
642 and this points to it. */
643 EXTERN struct link_map *_dl_sysinfo_map;
644
645# define PROCINFO_DECL
646# ifndef PROCINFO_CLASS
647# define PROCINFO_CLASS EXTERN
648# endif
649# include <dl-vdso-setup.c>
650#endif
651
652 /* Mask for more hardware capabilities that are available on some
653 platforms. */
654 EXTERN uint64_t _dl_hwcap2;
655
656 EXTERN enum dso_sort_algorithm _dl_dso_sort_algo;
657
658#ifdef SHARED
659 /* We add a function table to _rtld_global which is then used to
660 call the function instead of going through the PLT. The result
661 is that we can avoid exporting the functions and we do not jump
662 PLT relocations in libc.so. */
663 void (*_dl_debug_printf) (const char *, ...)
664 __attribute__ ((__format__ (__printf__, 1, 2)));
665 void (*_dl_mcount) (ElfW(Addr) frompc, ElfW(Addr) selfpc);
666 lookup_t (*_dl_lookup_symbol_x) (const char *, struct link_map *,
667 const ElfW(Sym) **, struct r_scope_elem *[],
668 const struct r_found_version *, int, int,
669 struct link_map *);
670 void *(*_dl_open) (const char *file, int mode, const void *caller_dlopen,
671 Lmid_t nsid, int argc, char *argv[], char *env[]);
672 void (*_dl_close) (void *map);
673 /* libdl in a secondary namespace (after dlopen) must use
674 _dl_catch_error from the main namespace, so it has to be
675 exported in some way. */
676 int (*_dl_catch_error) (const char **objname, const char **errstring,
677 bool *mallocedp, void (*operate) (void *),
678 void *args);
679 /* libdl in a secondary namespace must use free from the base
680 namespace. */
681 void (*_dl_error_free) (void *);
682 void *(*_dl_tls_get_addr_soft) (struct link_map *);
683
684 /* Called from __libc_shared to deallocate malloc'ed memory. */
685 void (*_dl_libc_freeres) (void);
686
687 /* Implementation of _dl_find_object. The public entry point is in
688 libc, and this is patched by __rtld_static_init to support static
689 dlopen. */
690 int (*_dl_find_object) (void *, struct dl_find_object *);
691
692 /* Dynamic linker operations used after static dlopen. */
693 const struct dlfcn_hook *_dl_dlfcn_hook;
694
695 /* List of auditing interfaces. */
696 struct audit_ifaces *_dl_audit;
697 unsigned int _dl_naudit;
698};
699# define __rtld_global_attribute__
700# if IS_IN (rtld)
701# define __rtld_local_attribute__ __attribute__ ((visibility ("hidden")))
702extern struct rtld_global_ro _rtld_local_ro
703 attribute_relro __rtld_local_attribute__;
704extern struct rtld_global_ro _rtld_global_ro
705 attribute_relro __rtld_global_attribute__;
706# undef __rtld_local_attribute__
707# else
708/* We cheat a bit here. We declare the variable as as const even
709 though it is at startup. */
710extern const struct rtld_global_ro _rtld_global_ro
711 attribute_relro __rtld_global_attribute__;
712# endif
713# undef __rtld_global_attribute__
714#endif
715#undef EXTERN
716
717#ifndef SHARED
718/* dl-support.c defines these and initializes them early on. */
719extern const ElfW(Phdr) *_dl_phdr;
720extern size_t _dl_phnum;
721#endif
722
723#if PTHREAD_IN_LIBC
724/* This function changes the permissions of all stacks (not just those
725 of the main stack). */
726int _dl_make_stacks_executable (void **stack_endp) attribute_hidden;
727#else
728/* This is the initial value of GL(dl_make_stack_executable_hook).
729 A threads library can change it. The ld.so implementation changes
730 the permissions of the main stack only. */
731extern int _dl_make_stack_executable (void **stack_endp);
732rtld_hidden_proto (_dl_make_stack_executable)
733#endif
734
735/* Variable pointing to the end of the stack (or close to it). This value
736 must be constant over the runtime of the application. Some programs
737 might use the variable which results in copy relocations on some
738 platforms. But this does not matter, ld.so can always use the local
739 copy. */
740extern void *__libc_stack_end
741#ifndef LIBC_STACK_END_NOT_RELRO
742 attribute_relro
743#endif
744 ;
745rtld_hidden_proto (__libc_stack_end)
746
747/* Parameters passed to the dynamic linker. */
748extern int _dl_argc attribute_hidden attribute_relro;
749extern char **_dl_argv attribute_relro;
750rtld_hidden_proto (_dl_argv)
751#define rtld_progname _dl_argv[0]
752
753/* Flag set at startup and cleared when the last initializer has run. */
754extern int _dl_starting_up;
755weak_extern (_dl_starting_up)
756rtld_hidden_proto (_dl_starting_up)
757
758/* Random data provided by the kernel. */
759extern void *_dl_random attribute_hidden attribute_relro;
760
761/* Write message on the debug file descriptor. The parameters are
762 interpreted as for a `printf' call. All the lines start with a
763 tag showing the PID. */
764extern void _dl_debug_printf (const char *fmt, ...)
765 __attribute__ ((__format__ (__printf__, 1, 2))) attribute_hidden;
766
767/* Write message on the debug file descriptor. The parameters are
768 interpreted as for a `printf' call. All the lines buf the first
769 start with a tag showing the PID. */
770extern void _dl_debug_printf_c (const char *fmt, ...)
771 __attribute__ ((__format__ (__printf__, 1, 2))) attribute_hidden;
772
773
774/* Write a message on the specified descriptor FD. The parameters are
775 interpreted as for a `printf' call. */
776extern void _dl_dprintf (int fd, const char *fmt, ...)
777 __attribute__ ((__format__ (__printf__, 2, 3)))
778 attribute_hidden;
779
780/* Write LENGTH bytes at BUFFER to FD, like write. Returns the number
781 of bytes written on success, or a negative error constant on
782 failure. */
783ssize_t _dl_write (int fd, const void *buffer, size_t length)
784 attribute_hidden;
785
786/* Write a message on the specified descriptor standard output. The
787 parameters are interpreted as for a `printf' call. */
788void _dl_printf (const char *fmt, ...)
789 attribute_hidden __attribute__ ((__format__ (__printf__, 1, 2)));
790
791/* Write a message on the specified descriptor standard error. The
792 parameters are interpreted as for a `printf' call. */
793void _dl_error_printf (const char *fmt, ...)
794 attribute_hidden __attribute__ ((__format__ (__printf__, 1, 2)));
795
796/* Write a message on the specified descriptor standard error and exit
797 the program. The parameters are interpreted as for a `printf' call. */
798void _dl_fatal_printf (const char *fmt, ...)
799 __attribute__ ((__format__ (__printf__, 1, 2), __noreturn__));
800rtld_hidden_proto (_dl_fatal_printf)
801
802/* An exception raised by the _dl_signal_error function family and
803 caught by _dl_catch_error function family. Exceptions themselves
804 are copied as part of the raise operation, but the strings are
805 not. */
806struct dl_exception
807{
808 const char *objname;
809 const char *errstring;
810
811 /* This buffer typically stores both objname and errstring
812 above. */
813 char *message_buffer;
814};
815
816/* Creates a new exception. This calls malloc; if allocation fails,
817 dummy values are inserted. OBJECT is the name of the problematical
818 shared object, or null if its a general problem. ERRSTRING is a
819 string describing the specific problem. */
820void _dl_exception_create (struct dl_exception *, const char *object,
821 const char *errstring)
822 __attribute__ ((nonnull (1, 3)));
823rtld_hidden_proto (_dl_exception_create)
824
825/* Used internally to implement dlerror message freeing. See
826 include/dlfcn.h and dlfcn/dlerror.c. */
827void _dl_error_free (void *ptr) attribute_hidden;
828
829/* Like _dl_exception_create, but create errstring from a format
830 string FMT. Currently, only "%s" and "%%" are supported as format
831 directives. */
832void _dl_exception_create_format (struct dl_exception *, const char *objname,
833 const char *fmt, ...)
834 __attribute__ ((nonnull (1, 3), format (printf, 3, 4)));
835rtld_hidden_proto (_dl_exception_create_format)
836
837/* Deallocate the exception, freeing allocated buffers (if
838 possible). */
839void _dl_exception_free (struct dl_exception *)
840 __attribute__ ((nonnull (1)));
841rtld_hidden_proto (_dl_exception_free)
842
843/* This function is called by all the internal dynamic linker
844 functions when they encounter an error. ERRCODE is either an
845 `errno' code or zero; it specifies the return value of
846 _dl_catch_error. OCCASION is included in the error message if the
847 process is terminated immediately. */
848void _dl_signal_exception (int errcode, struct dl_exception *,
849 const char *occasion)
850 __attribute__ ((__noreturn__));
851rtld_hidden_proto (_dl_signal_exception)
852
853/* Like _dl_signal_exception, but creates the exception first. */
854extern void _dl_signal_error (int errcode, const char *object,
855 const char *occasion, const char *errstring)
856 __attribute__ ((__noreturn__));
857rtld_hidden_proto (_dl_signal_error)
858
859/* Like _dl_signal_exception, but may return when called in the
860 context of _dl_receive_error. This is only used during ld.so
861 bootstrap. In static and profiled builds, this is equivalent to
862 _dl_signal_exception. */
863#if IS_IN (rtld)
864extern void _dl_signal_cexception (int errcode, struct dl_exception *,
865 const char *occasion) attribute_hidden;
866#else
867__attribute__ ((always_inline))
868static inline void
869_dl_signal_cexception (int errcode, struct dl_exception *exception,
870 const char *occasion)
871{
872 _dl_signal_exception (errcode, exception, occasion);
873}
874#endif
875
876/* See _dl_signal_cexception above. */
877#if IS_IN (rtld)
878extern void _dl_signal_cerror (int errcode, const char *object,
879 const char *occasion, const char *errstring)
880 attribute_hidden;
881#else
882__attribute__ ((always_inline))
883static inline void
884_dl_signal_cerror (int errcode, const char *object,
885 const char *occasion, const char *errstring)
886{
887 _dl_signal_error (errcode, object, occasion, errstring);
888}
889#endif
890
891/* Call OPERATE, receiving errors from `dl_signal_cerror'. Unlike
892 `_dl_catch_error' the operation is resumed after the OPERATE
893 function returns.
894 ARGS is passed as argument to OPERATE. */
895extern void _dl_receive_error (receiver_fct fct, void (*operate) (void *),
896 void *args) attribute_hidden;
897
898/* Call OPERATE, catching errors from `_dl_signal_error' and related
899 functions. If there is no error, *ERRSTRING is set to null. If
900 there is an error, *ERRSTRING is set to a string constructed from
901 the strings passed to _dl_signal_error, and the error code passed
902 is the return value and *OBJNAME is set to the object name which
903 experienced the problems. ERRSTRING if nonzero points to a
904 malloc'ed string which the caller has to free after use. ARGS is
905 passed as argument to OPERATE. MALLOCEDP is set to true only if
906 the returned string is allocated using the libc's malloc. */
907extern int _dl_catch_error (const char **objname, const char **errstring,
908 bool *mallocedp, void (*operate) (void *),
909 void *args) attribute_hidden;
910
911/* Call OPERATE (ARGS). If no error occurs, set *EXCEPTION to zero.
912 Otherwise, store a copy of the raised exception in *EXCEPTION,
913 which has to be freed by _dl_exception_free. As a special case, if
914 EXCEPTION is null, call OPERATE (ARGS) with exception handling
915 disabled (so that exceptions are fatal). */
916int _dl_catch_exception (struct dl_exception *exception,
917 void (*operate) (void *), void *args);
918rtld_hidden_proto (_dl_catch_exception)
919
920/* Open the shared object NAME and map in its segments.
921 LOADER's DT_RPATH is used in searching for NAME.
922 If the object is already opened, returns its existing map. */
923extern struct link_map *_dl_map_object (struct link_map *loader,
924 const char *name,
925 int type, int trace_mode, int mode,
926 Lmid_t nsid) attribute_hidden;
927
928/* Call _dl_map_object on the dependencies of MAP, and set up
929 MAP->l_searchlist. PRELOADS points to a vector of NPRELOADS previously
930 loaded objects that will be inserted into MAP->l_searchlist after MAP
931 but before its dependencies. */
932extern void _dl_map_object_deps (struct link_map *map,
933 struct link_map **preloads,
934 unsigned int npreloads, int trace_mode,
935 int open_mode)
936 attribute_hidden;
937
938/* Cache the locations of MAP's hash table. */
939extern void _dl_setup_hash (struct link_map *map) attribute_hidden;
940
941
942/* Collect the directories in the search path for LOADER's dependencies.
943 The data structure is defined in <dlfcn.h>. If COUNTING is true,
944 SI->dls_cnt and SI->dls_size are set; if false, those must be as set
945 by a previous call with COUNTING set, and SI must point to SI->dls_size
946 bytes to be used in filling in the result. */
947extern void _dl_rtld_di_serinfo (struct link_map *loader,
948 Dl_serinfo *si, bool counting);
949
950/* Process PT_GNU_PROPERTY program header PH in module L after
951 PT_LOAD segments are mapped from file FD. */
952void _dl_process_pt_gnu_property (struct link_map *l, int fd,
953 const ElfW(Phdr) *ph);
954
955
956/* Search loaded objects' symbol tables for a definition of the symbol
957 referred to by UNDEF. *SYM is the symbol table entry containing the
958 reference; it is replaced with the defining symbol, and the base load
959 address of the defining object is returned. SYMBOL_SCOPE is a
960 null-terminated list of object scopes to search; each object's
961 l_searchlist (i.e. the segment of the dependency tree starting at that
962 object) is searched in turn. REFERENCE_NAME should name the object
963 containing the reference; it is used in error messages.
964 TYPE_CLASS describes the type of symbol we are looking for. */
965enum
966 {
967 /* If necessary add dependency between user and provider object. */
968 DL_LOOKUP_ADD_DEPENDENCY = 1,
969 /* Return most recent version instead of default version for
970 unversioned lookup. */
971 DL_LOOKUP_RETURN_NEWEST = 2,
972 /* Set if dl_lookup* called with GSCOPE lock held. */
973 DL_LOOKUP_GSCOPE_LOCK = 4,
974 /* Set if dl_lookup is called for non-lazy relocation processing
975 from _dl_relocate_object in elf/dl-reloc.c. */
976 DL_LOOKUP_FOR_RELOCATE = 8,
977 };
978
979/* Lookup versioned symbol. */
980extern lookup_t _dl_lookup_symbol_x (const char *undef,
981 struct link_map *undef_map,
982 const ElfW(Sym) **sym,
983 struct r_scope_elem *symbol_scope[],
984 const struct r_found_version *version,
985 int type_class, int flags,
986 struct link_map *skip_map)
987 attribute_hidden;
988
989
990/* Restricted version of _dl_lookup_symbol_x. Searches MAP (and only
991 MAP) for the symbol UNDEF_NAME, with GNU hash NEW_HASH (computed
992 with dl_new_hash), symbol version VERSION, and symbol version hash
993 VERSION_HASH (computed with _dl_elf_hash). Returns a pointer to
994 the symbol table entry in MAP on success, or NULL on failure. MAP
995 must have symbol versioning information, or otherwise the result is
996 undefined. */
997const ElfW(Sym) *_dl_lookup_direct (struct link_map *map,
998 const char *undef_name,
999 uint32_t new_hash,
1000 const char *version,
1001 uint32_t version_hash) attribute_hidden;
1002
1003/* Add the new link_map NEW to the end of the namespace list. */
1004extern void _dl_add_to_namespace_list (struct link_map *new, Lmid_t nsid)
1005 attribute_hidden;
1006
1007/* Allocate a `struct link_map' for a new object being loaded. */
1008extern struct link_map *_dl_new_object (char *realname, const char *libname,
1009 int type, struct link_map *loader,
1010 int mode, Lmid_t nsid)
1011 attribute_hidden;
1012
1013/* Relocate the given object (if it hasn't already been).
1014 SCOPE is passed to _dl_lookup_symbol in symbol lookups.
1015 If RTLD_LAZY is set in RELOC-MODE, don't relocate its PLT. */
1016extern void _dl_relocate_object (struct link_map *map,
1017 struct r_scope_elem *scope[],
1018 int reloc_mode, int consider_profiling)
1019 attribute_hidden;
1020
1021/* Protect PT_GNU_RELRO area. */
1022extern void _dl_protect_relro (struct link_map *map) attribute_hidden;
1023
1024/* Call _dl_signal_error with a message about an unhandled reloc type.
1025 TYPE is the result of ELFW(R_TYPE) (r_info), i.e. an R_<CPU>_* value.
1026 PLT is nonzero if this was a PLT reloc; it just affects the message. */
1027extern void _dl_reloc_bad_type (struct link_map *map,
1028 unsigned int type, int plt)
1029 attribute_hidden __attribute__ ((__noreturn__));
1030
1031/* Check the version dependencies of all objects available through
1032 MAP. If VERBOSE print some more diagnostics. */
1033extern int _dl_check_all_versions (struct link_map *map, int verbose,
1034 int trace_mode) attribute_hidden;
1035
1036/* Check the version dependencies for MAP. If VERBOSE print some more
1037 diagnostics. */
1038extern int _dl_check_map_versions (struct link_map *map, int verbose,
1039 int trace_mode) attribute_hidden;
1040
1041/* Initialize the object in SCOPE by calling the constructors with
1042 ARGC, ARGV, and ENV as the parameters. */
1043extern void _dl_init (struct link_map *main_map, int argc, char **argv,
1044 char **env) attribute_hidden;
1045
1046/* Call the finalizer functions of all shared objects whose
1047 initializer functions have completed. */
1048extern void _dl_fini (void) attribute_hidden;
1049
1050/* Invoke the DT_FINI_ARRAY and DT_FINI destructors for MAP, which
1051 must be a struct link_map *. Can be used as an argument to
1052 _dl_catch_exception. */
1053void _dl_call_fini (void *map) attribute_hidden;
1054
1055/* Sort array MAPS according to dependencies of the contained objects.
1056 If FORCE_FIRST, MAPS[0] keeps its place even if the dependencies
1057 say otherwise. */
1058extern void _dl_sort_maps (struct link_map **maps, unsigned int nmaps,
1059 bool force_first, bool for_fini) attribute_hidden;
1060
1061/* The dynamic linker calls this function before and having changing
1062 any shared object mappings. The `r_state' member of `struct r_debug'
1063 says what change is taking place. This function's address is
1064 the value of the `r_brk' member. */
1065extern void _dl_debug_state (void);
1066rtld_hidden_proto (_dl_debug_state)
1067
1068/* Initialize `struct r_debug_extended' for the namespace NS. LDBASE
1069 is the run-time load address of the dynamic linker, to be put in the
1070 `r_ldbase' member. Return the address of the structure. */
1071extern struct r_debug *_dl_debug_initialize (ElfW(Addr) ldbase, Lmid_t ns)
1072 attribute_hidden;
1073
1074/* Update the `r_map' member and return the address of `struct r_debug'
1075 of the namespace NS. */
1076extern struct r_debug *_dl_debug_update (Lmid_t ns) attribute_hidden;
1077
1078/* Initialize the basic data structure for the search paths. SOURCE
1079 is either "LD_LIBRARY_PATH" or "--library-path".
1080 GLIBC_HWCAPS_PREPEND adds additional glibc-hwcaps subdirectories to
1081 search. GLIBC_HWCAPS_MASK is used to filter the built-in
1082 subdirectories if not NULL. */
1083extern void _dl_init_paths (const char *library_path, const char *source,
1084 const char *glibc_hwcaps_prepend,
1085 const char *glibc_hwcaps_mask)
1086 attribute_hidden;
1087
1088/* Gather the information needed to install the profiling tables and start
1089 the timers. */
1090extern void _dl_start_profile (void) attribute_hidden;
1091
1092/* The actual functions used to keep book on the calls. */
1093extern void _dl_mcount (ElfW(Addr) frompc, ElfW(Addr) selfpc);
1094rtld_hidden_proto (_dl_mcount)
1095
1096/* This function is simply a wrapper around the _dl_mcount function
1097 which does not require a FROMPC parameter since this is the
1098 calling function. */
1099extern void _dl_mcount_wrapper (void *selfpc);
1100
1101/* Show the members of the auxiliary array passed up from the kernel. */
1102extern void _dl_show_auxv (void) attribute_hidden;
1103
1104/* Return all environment variables starting with `LD_', one after the
1105 other. */
1106extern char *_dl_next_ld_env_entry (char ***position) attribute_hidden;
1107
1108/* Return an array with the names of the important hardware
1109 capabilities. PREPEND is a colon-separated list of glibc-hwcaps
1110 directories to search first. MASK is a colon-separated list used
1111 to filter the built-in glibc-hwcaps subdirectories. The length of
1112 the array is written to *SZ, and the maximum of all strings length
1113 is written to *MAX_CAPSTRLEN. */
1114const struct r_strlenpair *_dl_important_hwcaps (const char *prepend,
1115 const char *mask,
1116 size_t *sz,
1117 size_t *max_capstrlen)
1118 attribute_hidden;
1119
1120/* Look up NAME in ld.so.cache and return the file name stored there,
1121 or null if none is found. Caller must free returned string. */
1122extern char *_dl_load_cache_lookup (const char *name) attribute_hidden;
1123
1124/* If the system does not support MAP_COPY we cannot leave the file open
1125 all the time since this would create problems when the file is replaced.
1126 Therefore we provide this function to close the file and open it again
1127 once needed. */
1128extern void _dl_unload_cache (void) attribute_hidden;
1129
1130/* System-dependent function to read a file's whole contents in the
1131 most convenient manner available. *SIZEP gets the size of the
1132 file. On error MAP_FAILED is returned. */
1133extern void *_dl_sysdep_read_whole_file (const char *file, size_t *sizep,
1134 int prot) attribute_hidden;
1135
1136/* System-specific function to do initial startup for the dynamic linker.
1137 After this, file access calls and getenv must work. This is responsible
1138 for setting __libc_enable_secure if we need to be secure (e.g. setuid),
1139 and for setting _dl_argc and _dl_argv, and then calling _dl_main. */
1140extern ElfW(Addr) _dl_sysdep_start (void **start_argptr,
1141 void (*dl_main) (const ElfW(Phdr) *phdr,
1142 ElfW(Word) phnum,
1143 ElfW(Addr) *user_entry,
1144 ElfW(auxv_t) *auxv))
1145 attribute_hidden;
1146
1147extern void _dl_sysdep_start_cleanup (void) attribute_hidden;
1148
1149
1150/* Determine next available module ID and set the L l_tls_modid. */
1151extern void _dl_assign_tls_modid (struct link_map *l) attribute_hidden;
1152
1153/* Count the modules with TLS segments. */
1154extern size_t _dl_count_modids (void) attribute_hidden;
1155
1156/* Calculate offset of the TLS blocks in the static TLS block. */
1157extern void _dl_determine_tlsoffset (void) attribute_hidden;
1158
1159/* Calculate the size of the static TLS surplus, when the given
1160 number of audit modules are loaded. */
1161void _dl_tls_static_surplus_init (size_t naudit) attribute_hidden;
1162
1163/* This function is called very early from dl_main to set up TLS and
1164 other thread-related data structures. */
1165void __tls_pre_init_tp (void) attribute_hidden;
1166
1167/* This function is called after processor-specific initialization of
1168 the TCB and thread pointer via TLS_INIT_TP, to complete very early
1169 initialization of the thread library. */
1170void __tls_init_tp (void) attribute_hidden;
1171
1172#ifndef SHARED
1173/* Set up the TCB for statically linked applications. This is called
1174 early during startup because we always use TLS (for errno and the
1175 stack protector, among other things). */
1176void __libc_setup_tls (void);
1177
1178# if ENABLE_STATIC_PIE
1179/* Relocate static executable with PIE. */
1180extern void _dl_relocate_static_pie (void) attribute_hidden;
1181
1182/* Get a pointer to _dl_main_map. */
1183extern struct link_map * _dl_get_dl_main_map (void)
1184 __attribute__ ((visibility ("hidden")));
1185# else
1186# define _dl_relocate_static_pie()
1187# endif
1188#endif
1189
1190/* Perform early memory allocation, avoding a TCB dependency.
1191 Terminate the process if allocation fails. May attempt to use
1192 brk. */
1193void *_dl_early_allocate (size_t size) attribute_hidden;
1194
1195/* Initialize the DSO sort algorithm to use. */
1196#if !HAVE_TUNABLES
1197static inline void
1198__always_inline
1199_dl_sort_maps_init (void)
1200{
1201 /* This is optimized out if tunables are not enabled. */
1202}
1203#else
1204extern void _dl_sort_maps_init (void) attribute_hidden;
1205#endif
1206
1207/* Initialization of libpthread for statically linked applications.
1208 If libpthread is not linked in, this is an empty function. */
1209void __pthread_initialize_minimal (void) weak_function;
1210
1211/* Allocate memory for static TLS block (unless MEM is nonzero) and dtv. */
1212extern void *_dl_allocate_tls (void *mem);
1213rtld_hidden_proto (_dl_allocate_tls)
1214
1215/* Get size and alignment requirements of the static TLS block. */
1216extern void _dl_get_tls_static_info (size_t *sizep, size_t *alignp);
1217
1218extern void _dl_allocate_static_tls (struct link_map *map) attribute_hidden;
1219
1220/* These are internal entry points to the two halves of _dl_allocate_tls,
1221 only used within rtld.c itself at startup time. */
1222extern void *_dl_allocate_tls_storage (void) attribute_hidden;
1223extern void *_dl_allocate_tls_init (void *, bool);
1224rtld_hidden_proto (_dl_allocate_tls_init)
1225
1226/* True if the TCB has been set up. */
1227extern bool __rtld_tls_init_tp_called attribute_hidden;
1228
1229/* Deallocate memory allocated with _dl_allocate_tls. */
1230extern void _dl_deallocate_tls (void *tcb, bool dealloc_tcb);
1231rtld_hidden_proto (_dl_deallocate_tls)
1232
1233extern void _dl_nothread_init_static_tls (struct link_map *) attribute_hidden;
1234
1235/* Find origin of the executable. */
1236extern const char *_dl_get_origin (void) attribute_hidden;
1237
1238/* Count DSTs. */
1239extern size_t _dl_dst_count (const char *name) attribute_hidden;
1240
1241/* Substitute DST values. */
1242extern char *_dl_dst_substitute (struct link_map *l, const char *name,
1243 char *result) attribute_hidden;
1244
1245/* Open the shared object NAME, relocate it, and run its initializer if it
1246 hasn't already been run. MODE is as for `dlopen' (see <dlfcn.h>). If
1247 the object is already opened, returns its existing map. */
1248extern void *_dl_open (const char *name, int mode, const void *caller,
1249 Lmid_t nsid, int argc, char *argv[], char *env[])
1250 attribute_hidden;
1251
1252/* Free or queue for freeing scope OLD. If other threads might be
1253 in the middle of _dl_fixup, _dl_profile_fixup or dl*sym using the
1254 old scope, OLD can't be freed until no thread is using it. */
1255extern int _dl_scope_free (void *) attribute_hidden;
1256
1257
1258/* Add module to slot information data. If DO_ADD is false, only the
1259 required memory is allocated. Must be called with GL
1260 (dl_load_tls_lock) acquired. If the function has already been called
1261 for the link map L with !do_add, then this function will not raise
1262 an exception, otherwise it is possible that it encounters a memory
1263 allocation failure. */
1264extern void _dl_add_to_slotinfo (struct link_map *l, bool do_add)
1265 attribute_hidden;
1266
1267/* Update slot information data for at least the generation of the
1268 module with the given index. */
1269extern struct link_map *_dl_update_slotinfo (unsigned long int req_modid)
1270 attribute_hidden;
1271
1272/* Look up the module's TLS block as for __tls_get_addr,
1273 but never touch anything. Return null if it's not allocated yet. */
1274extern void *_dl_tls_get_addr_soft (struct link_map *l) attribute_hidden;
1275
1276extern int _dl_addr_inside_object (struct link_map *l, const ElfW(Addr) addr)
1277 attribute_hidden;
1278
1279/* Show show of an object. */
1280extern void _dl_show_scope (struct link_map *new, int from)
1281 attribute_hidden;
1282
1283extern struct link_map *_dl_find_dso_for_object (const ElfW(Addr) addr);
1284rtld_hidden_proto (_dl_find_dso_for_object)
1285
1286/* Initialization which is normally done by the dynamic linker. */
1287extern void _dl_non_dynamic_init (void)
1288 attribute_hidden;
1289
1290/* Used by static binaries to check the auxiliary vector. */
1291extern void _dl_aux_init (ElfW(auxv_t) *av)
1292 attribute_hidden;
1293
1294/* Initialize the static TLS space for the link map in all existing
1295 threads. */
1296#if PTHREAD_IN_LIBC
1297void _dl_init_static_tls (struct link_map *map) attribute_hidden;
1298#endif
1299static inline void
1300dl_init_static_tls (struct link_map *map)
1301{
1302#if PTHREAD_IN_LIBC
1303 /* The stack list is available to ld.so, so the initialization can
1304 be handled within ld.so directly. */
1305 _dl_init_static_tls (map);
1306#else
1307 GL (dl_init_static_tls) (map);
1308#endif
1309}
1310
1311#ifndef SHARED
1312/* Called before relocating ld.so during static dlopen. This can be
1313 used to partly initialize the dormant ld.so copy in the static
1314 dlopen namespace. */
1315void __rtld_static_init (struct link_map *map) attribute_hidden;
1316#endif
1317
1318/* Return true if the ld.so copy in this namespace is actually active
1319 and working. If false, the dl_open/dlfcn hooks have to be used to
1320 call into the outer dynamic linker (which happens after static
1321 dlopen). */
1322#ifdef SHARED
1323static inline bool
1324rtld_active (void)
1325{
1326 /* The default-initialized variable does not have a non-zero
1327 dl_init_all_dirs member, so this allows us to recognize an
1328 initialized and active ld.so copy. */
1329 return GLRO(dl_init_all_dirs) != NULL;
1330}
1331
1332static inline struct auditstate *
1333link_map_audit_state (struct link_map *l, size_t index)
1334{
1335 if (l == &GL (dl_rtld_map))
1336 /* The auditstate array is stored separately. */
1337 return &GL (dl_rtld_auditstate) [index];
1338 else
1339 {
1340 /* The auditstate array follows the link map in memory. */
1341 struct auditstate *base = (struct auditstate *) (l + 1);
1342 return &base[index];
1343 }
1344}
1345
1346/* Call the la_objsearch from the audit modules from the link map L. If
1347 ORIGNAME is non NULL, it is updated with the revious name prior calling
1348 la_objsearch. */
1349const char *_dl_audit_objsearch (const char *name, struct link_map *l,
1350 unsigned int code)
1351 attribute_hidden;
1352
1353/* Call the la_activity from the audit modules from the link map L and issues
1354 the ACTION argument. */
1355void _dl_audit_activity_map (struct link_map *l, int action)
1356 attribute_hidden;
1357
1358/* Call the la_activity from the audit modules from the link map from the
1359 namespace NSID and issues the ACTION argument. */
1360void _dl_audit_activity_nsid (Lmid_t nsid, int action)
1361 attribute_hidden;
1362
1363/* Call the la_objopen from the audit modules for the link_map L on the
1364 namespace identification NSID. */
1365void _dl_audit_objopen (struct link_map *l, Lmid_t nsid)
1366 attribute_hidden;
1367
1368/* Call the la_objclose from the audit modules for the link_map L. */
1369void _dl_audit_objclose (struct link_map *l)
1370 attribute_hidden;
1371
1372/* Call the la_preinit from the audit modules for the link_map L. */
1373void _dl_audit_preinit (struct link_map *l);
1374
1375/* Call the la_symbind{32,64} from the audit modules for the link_map L. If
1376 RELOC_RESULT is NULL it assumes the symbol to be bind-now and will set
1377 the flags with LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT prior calling
1378 la_symbind{32,64}. */
1379void _dl_audit_symbind (struct link_map *l, struct reloc_result *reloc_result,
1380 const ElfW(Sym) *defsym, DL_FIXUP_VALUE_TYPE *value,
1381 lookup_t result)
1382 attribute_hidden;
1383/* Same as _dl_audit_symbind, but also sets LA_SYMB_DLSYM flag. */
1384void _dl_audit_symbind_alt (struct link_map *l, const ElfW(Sym) *ref,
1385 void **value, lookup_t result);
1386rtld_hidden_proto (_dl_audit_symbind_alt)
1387void _dl_audit_pltenter (struct link_map *l, struct reloc_result *reloc_result,
1388 DL_FIXUP_VALUE_TYPE *value, void *regs,
1389 long int *framesize)
1390 attribute_hidden;
1391void DL_ARCH_FIXUP_ATTRIBUTE _dl_audit_pltexit (struct link_map *l,
1392 ElfW(Word) reloc_arg,
1393 const void *inregs,
1394 void *outregs)
1395 attribute_hidden;
1396#endif /* SHARED */
1397
1398#if PTHREAD_IN_LIBC && defined SHARED
1399/* Recursive locking implementation for use within the dynamic loader.
1400 Used to define the __rtld_lock_lock_recursive and
1401 __rtld_lock_unlock_recursive via <libc-lock.h>. Initialized to a
1402 no-op dummy implementation early. Similar
1403 to GL (dl_rtld_lock_recursive) and GL (dl_rtld_unlock_recursive)
1404 in !PTHREAD_IN_LIBC builds. */
1405extern int (*___rtld_mutex_lock) (pthread_mutex_t *) attribute_hidden;
1406extern int (*___rtld_mutex_unlock) (pthread_mutex_t *lock) attribute_hidden;
1407
1408/* Called after libc has been loaded, but before RELRO is activated.
1409 Used to initialize the function pointers to the actual
1410 implementations. */
1411void __rtld_mutex_init (void) attribute_hidden;
1412#else /* !PTHREAD_IN_LIBC */
1413static inline void
1414__rtld_mutex_init (void)
1415{
1416 /* The initialization happens later (!PTHREAD_IN_LIBC) or is not
1417 needed at all (!SHARED). */
1418}
1419#endif /* !PTHREAD_IN_LIBC */
1420
1421/* Implementation of GL (dl_libc_freeres). */
1422void __rtld_libc_freeres (void) attribute_hidden;
1423
1424void __thread_gscope_wait (void) attribute_hidden;
1425# define THREAD_GSCOPE_WAIT() __thread_gscope_wait ()
1426
1427__END_DECLS
1428
1429#endif /* ldsodefs.h */
1430