1 | /* Run-time dynamic linker data structures for loaded ELF shared objects. |
2 | Copyright (C) 1995-2020 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 <libc-lock.h> |
39 | #include <hp-timing.h> |
40 | #include <tls.h> |
41 | |
42 | __BEGIN_DECLS |
43 | |
44 | #define VERSYMIDX(sym) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGIDX (sym)) |
45 | #define VALIDX(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM \ |
46 | + DT_EXTRANUM + DT_VALTAGIDX (tag)) |
47 | #define ADDRIDX(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM \ |
48 | + DT_EXTRANUM + DT_VALNUM + DT_ADDRTAGIDX (tag)) |
49 | |
50 | /* Type of GNU hash which the machine uses. */ |
51 | #ifndef ELF_MACHINE_GNU_HASH_ADDRIDX |
52 | # define ELF_MACHINE_GNU_HASH_ADDRIDX ADDRIDX (DT_GNU_HASH) |
53 | #endif |
54 | |
55 | /* Calculate the index of a symbol in GNU hash. */ |
56 | #ifndef ELF_MACHINE_HASH_SYMIDX |
57 | # define ELF_MACHINE_HASH_SYMIDX(map, hasharr) \ |
58 | ((hasharr) - (map)->l_gnu_chain_zero) |
59 | #endif |
60 | |
61 | /* Setup MIPS xhash. Defined only for MIPS. */ |
62 | #ifndef ELF_MACHINE_XHASH_SETUP |
63 | # define ELF_MACHINE_XHASH_SETUP(hash32, symbias, map) \ |
64 | ((void) (hash32), (void) (symbias), (void) (map)) |
65 | #endif |
66 | |
67 | /* We use this macro to refer to ELF types independent of the native wordsize. |
68 | `ElfW(TYPE)' is used in place of `Elf32_TYPE' or `Elf64_TYPE'. */ |
69 | #define ELFW(type) _ElfW (ELF, __ELF_NATIVE_CLASS, type) |
70 | |
71 | /* All references to the value of l_info[DT_PLTGOT], |
72 | l_info[DT_STRTAB], l_info[DT_SYMTAB], l_info[DT_RELA], |
73 | l_info[DT_REL], l_info[DT_JMPREL], and l_info[VERSYMIDX (DT_VERSYM)] |
74 | have to be accessed via the D_PTR macro. The macro is needed since for |
75 | most architectures the entry is already relocated - but for some not |
76 | and we need to relocate at access time. */ |
77 | #ifdef DL_RO_DYN_SECTION |
78 | # define D_PTR(map, i) ((map)->i->d_un.d_ptr + (map)->l_addr) |
79 | #else |
80 | # define D_PTR(map, i) (map)->i->d_un.d_ptr |
81 | #endif |
82 | |
83 | /* Result of the lookup functions and how to retrieve the base address. */ |
84 | typedef struct link_map *lookup_t; |
85 | #define LOOKUP_VALUE(map) map |
86 | #define LOOKUP_VALUE_ADDRESS(map, set) ((set) || (map) ? (map)->l_addr : 0) |
87 | |
88 | /* Calculate the address of symbol REF using the base address from map MAP, |
89 | if non-NULL. Don't check for NULL map if MAP_SET is TRUE. */ |
90 | #define SYMBOL_ADDRESS(map, ref, map_set) \ |
91 | ((ref) == NULL ? 0 \ |
92 | : (__glibc_unlikely ((ref)->st_shndx == SHN_ABS) ? 0 \ |
93 | : LOOKUP_VALUE_ADDRESS (map, map_set)) + (ref)->st_value) |
94 | |
95 | /* On some architectures a pointer to a function is not just a pointer |
96 | to the actual code of the function but rather an architecture |
97 | specific descriptor. */ |
98 | #ifndef ELF_FUNCTION_PTR_IS_SPECIAL |
99 | # define DL_SYMBOL_ADDRESS(map, ref) \ |
100 | (void *) SYMBOL_ADDRESS (map, ref, false) |
101 | # define DL_LOOKUP_ADDRESS(addr) ((ElfW(Addr)) (addr)) |
102 | # define DL_CALL_DT_INIT(map, start, argc, argv, env) \ |
103 | ((init_t) (start)) (argc, argv, env) |
104 | # define DL_CALL_DT_FINI(map, start) ((fini_t) (start)) () |
105 | #endif |
106 | |
107 | /* On some architectures dladdr can't use st_size of all symbols this way. */ |
108 | #define DL_ADDR_SYM_MATCH(L, SYM, MATCHSYM, ADDR) \ |
109 | ((ADDR) >= (L)->l_addr + (SYM)->st_value \ |
110 | && ((((SYM)->st_shndx == SHN_UNDEF || (SYM)->st_size == 0) \ |
111 | && (ADDR) == (L)->l_addr + (SYM)->st_value) \ |
112 | || (ADDR) < (L)->l_addr + (SYM)->st_value + (SYM)->st_size) \ |
113 | && ((MATCHSYM) == NULL || (MATCHSYM)->st_value < (SYM)->st_value)) |
114 | |
115 | /* According to the ELF gABI no STV_HIDDEN or STV_INTERNAL symbols are |
116 | expected to be present in dynamic symbol tables as they should have |
117 | been either removed or converted to STB_LOCAL binding by the static |
118 | linker. However some GNU binutils versions produce such symbols in |
119 | some cases. To prevent such symbols present in a buggy binary from |
120 | preempting global symbols we filter them out with this predicate. */ |
121 | static __always_inline bool |
122 | dl_symbol_visibility_binds_local_p (const ElfW(Sym) *sym) |
123 | { |
124 | return (ELFW(ST_VISIBILITY) (sym->st_other) == STV_HIDDEN |
125 | || ELFW(ST_VISIBILITY) (sym->st_other) == STV_INTERNAL); |
126 | } |
127 | |
128 | /* Unmap a loaded object, called by _dl_close (). */ |
129 | #ifndef DL_UNMAP_IS_SPECIAL |
130 | # define DL_UNMAP(map) _dl_unmap_segments (map) |
131 | #endif |
132 | |
133 | /* By default we do not need special support to initialize DSOs loaded |
134 | by statically linked binaries. */ |
135 | #ifndef DL_STATIC_INIT |
136 | # define DL_STATIC_INIT(map) |
137 | #endif |
138 | |
139 | /* Reloc type classes as returned by elf_machine_type_class(). |
140 | ELF_RTYPE_CLASS_PLT means this reloc should not be satisfied by |
141 | some PLT symbol, ELF_RTYPE_CLASS_COPY means this reloc should not be |
142 | satisfied by any symbol in the executable. Some architectures do |
143 | not support copy relocations. In this case we define the macro to |
144 | zero so that the code for handling them gets automatically optimized |
145 | out. ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA means address of protected |
146 | data defined in the shared library may be external, i.e., due to copy |
147 | relocation. */ |
148 | #define ELF_RTYPE_CLASS_PLT 1 |
149 | #ifndef DL_NO_COPY_RELOCS |
150 | # define ELF_RTYPE_CLASS_COPY 2 |
151 | #else |
152 | # define ELF_RTYPE_CLASS_COPY 0 |
153 | #endif |
154 | /* If DL_EXTERN_PROTECTED_DATA is defined, address of protected data |
155 | defined in the shared library may be external, i.e., due to copy |
156 | relocation. */ |
157 | #ifdef DL_EXTERN_PROTECTED_DATA |
158 | # define ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA 4 |
159 | #else |
160 | # define ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA 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. */ |
184 | struct 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 | |
195 | enum r_dir_status { unknown, nonexisting, existing }; |
196 | |
197 | struct 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 | |
214 | struct 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. */ |
222 | struct 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 | /* Bit masks for the objects which valid callers can come from to |
232 | functions with restricted interface. */ |
233 | enum allowmask |
234 | { |
235 | allow_libc = 1, |
236 | allow_libdl = 2, |
237 | allow_libpthread = 4, |
238 | allow_ldso = 8 |
239 | }; |
240 | |
241 | |
242 | struct audit_ifaces |
243 | { |
244 | void (*activity) (uintptr_t *, unsigned int); |
245 | char *(*objsearch) (const char *, uintptr_t *, unsigned int); |
246 | unsigned int (*objopen) (struct link_map *, Lmid_t, uintptr_t *); |
247 | void (*preinit) (uintptr_t *); |
248 | union |
249 | { |
250 | uintptr_t (*symbind32) (Elf32_Sym *, unsigned int, uintptr_t *, |
251 | uintptr_t *, unsigned int *, const char *); |
252 | uintptr_t (*symbind64) (Elf64_Sym *, unsigned int, uintptr_t *, |
253 | uintptr_t *, unsigned int *, const char *); |
254 | }; |
255 | union |
256 | { |
257 | #ifdef ARCH_PLTENTER_MEMBERS |
258 | ARCH_PLTENTER_MEMBERS; |
259 | #endif |
260 | }; |
261 | union |
262 | { |
263 | #ifdef ARCH_PLTEXIT_MEMBERS |
264 | ARCH_PLTEXIT_MEMBERS; |
265 | #endif |
266 | }; |
267 | unsigned int (*objclose) (uintptr_t *); |
268 | |
269 | struct audit_ifaces *next; |
270 | }; |
271 | |
272 | |
273 | /* Test whether given NAME matches any of the names of the given object. */ |
274 | extern int _dl_name_match_p (const char *__name, const struct link_map *__map) |
275 | attribute_hidden; |
276 | |
277 | /* Compute next higher prime number. */ |
278 | extern unsigned long int _dl_higher_prime_number (unsigned long int n) |
279 | attribute_hidden; |
280 | |
281 | /* A stripped down strtoul-like implementation. */ |
282 | uint64_t _dl_strtoul (const char *, char **) attribute_hidden; |
283 | |
284 | /* Function used as argument for `_dl_receive_error' function. The |
285 | arguments are the error code, error string, and the objname the |
286 | error occurred in. */ |
287 | typedef void (*receiver_fct) (int, const char *, const char *); |
288 | |
289 | /* Internal functions of the run-time dynamic linker. |
290 | These can be accessed if you link again the dynamic linker |
291 | as a shared library, as in `-lld' or `/lib/ld.so' explicitly; |
292 | but are not normally of interest to user programs. |
293 | |
294 | The `-ldl' library functions in <dlfcn.h> provide a simple |
295 | user interface to run-time dynamic linking. */ |
296 | |
297 | |
298 | #ifndef SHARED |
299 | # define EXTERN extern |
300 | # define GL(name) _##name |
301 | #else |
302 | # define EXTERN |
303 | # if IS_IN (rtld) |
304 | # define GL(name) _rtld_local._##name |
305 | # else |
306 | # define GL(name) _rtld_global._##name |
307 | # endif |
308 | struct rtld_global |
309 | { |
310 | #endif |
311 | /* Don't change the order of the following elements. 'dl_loaded' |
312 | must remain the first element. Forever. */ |
313 | |
314 | /* Non-shared code has no support for multiple namespaces. */ |
315 | #ifdef SHARED |
316 | # define DL_NNS 16 |
317 | #else |
318 | # define DL_NNS 1 |
319 | #endif |
320 | EXTERN struct link_namespaces |
321 | { |
322 | /* A pointer to the map for the main map. */ |
323 | struct link_map *_ns_loaded; |
324 | /* Number of object in the _dl_loaded list. */ |
325 | unsigned int _ns_nloaded; |
326 | /* Direct pointer to the searchlist of the main object. */ |
327 | struct r_scope_elem *_ns_main_searchlist; |
328 | /* This is zero at program start to signal that the global scope map is |
329 | allocated by rtld. Later it keeps the size of the map. It might be |
330 | reset if in _dl_close if the last global object is removed. */ |
331 | unsigned int _ns_global_scope_alloc; |
332 | |
333 | /* During dlopen, this is the number of objects that still need to |
334 | be added to the global scope map. It has to be taken into |
335 | account when resizing the map, for future map additions after |
336 | recursive dlopen calls from ELF constructors. */ |
337 | unsigned int _ns_global_scope_pending_adds; |
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 _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 | |
373 | /* Incremented whenever something may have been added to dl_loaded. */ |
374 | EXTERN unsigned long long _dl_load_adds; |
375 | |
376 | /* The object to be initialized first. */ |
377 | EXTERN struct link_map *_dl_initfirst; |
378 | |
379 | /* Map of shared object to be profiled. */ |
380 | EXTERN struct link_map *_dl_profile_map; |
381 | |
382 | /* Counters for the number of relocations performed. */ |
383 | EXTERN unsigned long int _dl_num_relocations; |
384 | EXTERN unsigned long int _dl_num_cache_relocations; |
385 | |
386 | /* List of search directories. */ |
387 | EXTERN struct r_search_path_elem *_dl_all_dirs; |
388 | |
389 | /* Structure describing the dynamic linker itself. */ |
390 | EXTERN struct link_map _dl_rtld_map; |
391 | #ifdef SHARED |
392 | /* Used to store the audit information for the link map of the |
393 | dynamic loader. */ |
394 | struct auditstate _dl_rtld_auditstate[DL_NNS]; |
395 | #endif |
396 | |
397 | #if defined SHARED && defined _LIBC_REENTRANT \ |
398 | && defined __rtld_lock_default_lock_recursive |
399 | EXTERN void (*_dl_rtld_lock_recursive) (void *); |
400 | EXTERN void (*_dl_rtld_unlock_recursive) (void *); |
401 | #endif |
402 | |
403 | /* Get architecture specific definitions. */ |
404 | #define PROCINFO_DECL |
405 | #ifndef PROCINFO_CLASS |
406 | # define PROCINFO_CLASS EXTERN |
407 | #endif |
408 | #include <dl-procruntime.c> |
409 | |
410 | /* If loading a shared object requires that we make the stack executable |
411 | when it was not, we do it by calling this function. |
412 | It returns an errno code or zero on success. */ |
413 | EXTERN int (*_dl_make_stack_executable_hook) (void **); |
414 | |
415 | /* Prevailing state of the stack, PF_X indicating it's executable. */ |
416 | EXTERN ElfW(Word) _dl_stack_flags; |
417 | |
418 | /* Flag signalling whether there are gaps in the module ID allocation. */ |
419 | EXTERN bool _dl_tls_dtv_gaps; |
420 | /* Highest dtv index currently needed. */ |
421 | EXTERN size_t _dl_tls_max_dtv_idx; |
422 | /* Information about the dtv slots. */ |
423 | EXTERN struct dtv_slotinfo_list |
424 | { |
425 | size_t len; |
426 | struct dtv_slotinfo_list *next; |
427 | struct dtv_slotinfo |
428 | { |
429 | size_t gen; |
430 | struct link_map *map; |
431 | } slotinfo[]; |
432 | } *_dl_tls_dtv_slotinfo_list; |
433 | /* Number of modules in the static TLS block. */ |
434 | EXTERN size_t _dl_tls_static_nelem; |
435 | /* Size of the static TLS block. */ |
436 | EXTERN size_t _dl_tls_static_size; |
437 | /* Size actually allocated in the static TLS block. */ |
438 | EXTERN size_t _dl_tls_static_used; |
439 | /* Alignment requirement of the static TLS block. */ |
440 | EXTERN size_t _dl_tls_static_align; |
441 | |
442 | /* Number of additional entries in the slotinfo array of each slotinfo |
443 | list element. A large number makes it almost certain take we never |
444 | have to iterate beyond the first element in the slotinfo list. */ |
445 | #define TLS_SLOTINFO_SURPLUS (62) |
446 | |
447 | /* Number of additional slots in the dtv allocated. */ |
448 | #define DTV_SURPLUS (14) |
449 | |
450 | /* Initial dtv of the main thread, not allocated with normal malloc. */ |
451 | EXTERN void *_dl_initial_dtv; |
452 | /* Generation counter for the dtv. */ |
453 | EXTERN size_t _dl_tls_generation; |
454 | |
455 | EXTERN void (*_dl_init_static_tls) (struct link_map *); |
456 | |
457 | EXTERN void (*_dl_wait_lookup_done) (void); |
458 | |
459 | /* Scopes to free after next THREAD_GSCOPE_WAIT (). */ |
460 | EXTERN struct dl_scope_free_list |
461 | { |
462 | size_t count; |
463 | void *list[50]; |
464 | } *_dl_scope_free_list; |
465 | #if !THREAD_GSCOPE_IN_TCB |
466 | EXTERN int _dl_thread_gscope_count; |
467 | #endif |
468 | #ifdef SHARED |
469 | }; |
470 | # define __rtld_global_attribute__ |
471 | # if IS_IN (rtld) |
472 | # ifdef HAVE_SDATA_SECTION |
473 | # define __rtld_local_attribute__ \ |
474 | __attribute__ ((visibility ("hidden"), section (".sdata"))) |
475 | # undef __rtld_global_attribute__ |
476 | # define __rtld_global_attribute__ __attribute__ ((section (".sdata"))) |
477 | # else |
478 | # define __rtld_local_attribute__ __attribute__ ((visibility ("hidden"))) |
479 | # endif |
480 | extern struct rtld_global _rtld_local __rtld_local_attribute__; |
481 | # undef __rtld_local_attribute__ |
482 | # endif |
483 | extern struct rtld_global _rtld_global __rtld_global_attribute__; |
484 | # undef __rtld_global_attribute__ |
485 | #endif |
486 | |
487 | #ifndef SHARED |
488 | # define GLRO(name) _##name |
489 | #else |
490 | # if IS_IN (rtld) |
491 | # define GLRO(name) _rtld_local_ro._##name |
492 | # else |
493 | # define GLRO(name) _rtld_global_ro._##name |
494 | # endif |
495 | struct rtld_global_ro |
496 | { |
497 | #endif |
498 | |
499 | /* If nonzero the appropriate debug information is printed. */ |
500 | EXTERN int _dl_debug_mask; |
501 | #define DL_DEBUG_LIBS (1 << 0) |
502 | #define DL_DEBUG_IMPCALLS (1 << 1) |
503 | #define DL_DEBUG_BINDINGS (1 << 2) |
504 | #define DL_DEBUG_SYMBOLS (1 << 3) |
505 | #define DL_DEBUG_VERSIONS (1 << 4) |
506 | #define DL_DEBUG_RELOC (1 << 5) |
507 | #define DL_DEBUG_FILES (1 << 6) |
508 | #define DL_DEBUG_STATISTICS (1 << 7) |
509 | #define DL_DEBUG_UNUSED (1 << 8) |
510 | #define DL_DEBUG_SCOPES (1 << 9) |
511 | /* These two are used only internally. */ |
512 | #define DL_DEBUG_HELP (1 << 10) |
513 | #define DL_DEBUG_PRELINK (1 << 11) |
514 | |
515 | /* OS version. */ |
516 | EXTERN unsigned int _dl_osversion; |
517 | /* Platform name. */ |
518 | EXTERN const char *_dl_platform; |
519 | EXTERN size_t _dl_platformlen; |
520 | |
521 | /* Cached value of `getpagesize ()'. */ |
522 | EXTERN size_t _dl_pagesize; |
523 | |
524 | /* Do we read from ld.so.cache? */ |
525 | EXTERN int _dl_inhibit_cache; |
526 | |
527 | /* Copy of the content of `_dl_main_searchlist' at startup time. */ |
528 | EXTERN struct r_scope_elem _dl_initial_searchlist; |
529 | |
530 | /* CLK_TCK as reported by the kernel. */ |
531 | EXTERN int _dl_clktck; |
532 | |
533 | /* If nonzero print warnings messages. */ |
534 | EXTERN int _dl_verbose; |
535 | |
536 | /* File descriptor to write debug messages to. */ |
537 | EXTERN int _dl_debug_fd; |
538 | |
539 | /* Do we do lazy relocations? */ |
540 | EXTERN int _dl_lazy; |
541 | |
542 | /* Nonzero if runtime lookups should not update the .got/.plt. */ |
543 | EXTERN int _dl_bind_not; |
544 | |
545 | /* Nonzero if references should be treated as weak during runtime |
546 | linking. */ |
547 | EXTERN int _dl_dynamic_weak; |
548 | |
549 | /* Default floating-point control word. */ |
550 | EXTERN fpu_control_t _dl_fpu_control; |
551 | |
552 | /* Expected cache ID. */ |
553 | EXTERN int _dl_correct_cache_id; |
554 | |
555 | /* Mask for hardware capabilities that are available. */ |
556 | EXTERN uint64_t _dl_hwcap; |
557 | |
558 | #if !HAVE_TUNABLES |
559 | /* Mask for important hardware capabilities we honour. */ |
560 | EXTERN uint64_t _dl_hwcap_mask; |
561 | #endif |
562 | |
563 | #ifdef HAVE_AUX_VECTOR |
564 | /* Pointer to the auxv list supplied to the program at startup. */ |
565 | EXTERN ElfW(auxv_t) *_dl_auxv; |
566 | #endif |
567 | |
568 | /* Get architecture specific definitions. */ |
569 | #include <dl-procinfo.c> |
570 | |
571 | /* Names of shared object for which the RPATH should be ignored. */ |
572 | EXTERN const char *_dl_inhibit_rpath; |
573 | |
574 | /* Location of the binary. */ |
575 | EXTERN const char *_dl_origin_path; |
576 | |
577 | /* -1 if the dynamic linker should honor library load bias, |
578 | 0 if not, -2 use the default (honor biases for normal |
579 | binaries, don't honor for PIEs). */ |
580 | EXTERN ElfW(Addr) _dl_use_load_bias; |
581 | |
582 | /* Name of the shared object to be profiled (if any). */ |
583 | EXTERN const char *_dl_profile; |
584 | /* Filename of the output file. */ |
585 | EXTERN const char *_dl_profile_output; |
586 | /* Name of the object we want to trace the prelinking. */ |
587 | EXTERN const char *_dl_trace_prelink; |
588 | /* Map of shared object to be prelink traced. */ |
589 | EXTERN struct link_map *_dl_trace_prelink_map; |
590 | |
591 | /* All search directories defined at startup. This is assigned a |
592 | non-NULL pointer by the ld.so startup code (after initialization |
593 | to NULL), so this can also serve as an indicator whether a copy |
594 | of ld.so is initialized and active. See the rtld_active function |
595 | below. */ |
596 | EXTERN struct r_search_path_elem *_dl_init_all_dirs; |
597 | |
598 | #ifdef NEED_DL_SYSINFO |
599 | /* Syscall handling improvements. This is very specific to x86. */ |
600 | EXTERN uintptr_t _dl_sysinfo; |
601 | #endif |
602 | |
603 | #ifdef NEED_DL_SYSINFO_DSO |
604 | /* The vsyscall page is a virtual DSO pre-mapped by the kernel. |
605 | This points to its ELF header. */ |
606 | EXTERN const ElfW(Ehdr) *_dl_sysinfo_dso; |
607 | |
608 | /* At startup time we set up the normal DSO data structure for it, |
609 | and this points to it. */ |
610 | EXTERN struct link_map *_dl_sysinfo_map; |
611 | |
612 | # define PROCINFO_DECL |
613 | # ifndef PROCINFO_CLASS |
614 | # define PROCINFO_CLASS EXTERN |
615 | # endif |
616 | # include <dl-vdso-setup.c> |
617 | #endif |
618 | |
619 | /* Mask for more hardware capabilities that are available on some |
620 | platforms. */ |
621 | EXTERN uint64_t _dl_hwcap2; |
622 | |
623 | #ifdef SHARED |
624 | /* We add a function table to _rtld_global which is then used to |
625 | call the function instead of going through the PLT. The result |
626 | is that we can avoid exporting the functions and we do not jump |
627 | PLT relocations in libc.so. */ |
628 | void (*_dl_debug_printf) (const char *, ...) |
629 | __attribute__ ((__format__ (__printf__, 1, 2))); |
630 | void (*_dl_mcount) (ElfW(Addr) frompc, ElfW(Addr) selfpc); |
631 | lookup_t (*_dl_lookup_symbol_x) (const char *, struct link_map *, |
632 | const ElfW(Sym) **, struct r_scope_elem *[], |
633 | const struct r_found_version *, int, int, |
634 | struct link_map *); |
635 | void *(*_dl_open) (const char *file, int mode, const void *caller_dlopen, |
636 | Lmid_t nsid, int argc, char *argv[], char *env[]); |
637 | void (*_dl_close) (void *map); |
638 | void *(*_dl_tls_get_addr_soft) (struct link_map *); |
639 | #ifdef HAVE_DL_DISCOVER_OSVERSION |
640 | int (*_dl_discover_osversion) (void); |
641 | #endif |
642 | |
643 | /* List of auditing interfaces. */ |
644 | struct audit_ifaces *_dl_audit; |
645 | unsigned int _dl_naudit; |
646 | }; |
647 | # define __rtld_global_attribute__ |
648 | # if IS_IN (rtld) |
649 | # define __rtld_local_attribute__ __attribute__ ((visibility ("hidden"))) |
650 | extern struct rtld_global_ro _rtld_local_ro |
651 | attribute_relro __rtld_local_attribute__; |
652 | extern struct rtld_global_ro _rtld_global_ro |
653 | attribute_relro __rtld_global_attribute__; |
654 | # undef __rtld_local_attribute__ |
655 | # else |
656 | /* We cheat a bit here. We declare the variable as as const even |
657 | though it is at startup. */ |
658 | extern const struct rtld_global_ro _rtld_global_ro |
659 | attribute_relro __rtld_global_attribute__; |
660 | # endif |
661 | # undef __rtld_global_attribute__ |
662 | #endif |
663 | #undef EXTERN |
664 | |
665 | #ifndef SHARED |
666 | /* dl-support.c defines these and initializes them early on. */ |
667 | extern const ElfW(Phdr) *_dl_phdr; |
668 | extern size_t _dl_phnum; |
669 | #endif |
670 | |
671 | /* This is the initial value of GL(dl_make_stack_executable_hook). |
672 | A threads library can change it. */ |
673 | extern int _dl_make_stack_executable (void **stack_endp); |
674 | rtld_hidden_proto (_dl_make_stack_executable) |
675 | |
676 | /* Variable pointing to the end of the stack (or close to it). This value |
677 | must be constant over the runtime of the application. Some programs |
678 | might use the variable which results in copy relocations on some |
679 | platforms. But this does not matter, ld.so can always use the local |
680 | copy. */ |
681 | extern void *__libc_stack_end |
682 | #ifndef LIBC_STACK_END_NOT_RELRO |
683 | attribute_relro |
684 | #endif |
685 | ; |
686 | rtld_hidden_proto (__libc_stack_end) |
687 | |
688 | /* Parameters passed to the dynamic linker. */ |
689 | extern int _dl_argc attribute_hidden attribute_relro; |
690 | extern char **_dl_argv |
691 | #ifndef DL_ARGV_NOT_RELRO |
692 | attribute_relro |
693 | #endif |
694 | ; |
695 | rtld_hidden_proto (_dl_argv) |
696 | #if IS_IN (rtld) |
697 | extern unsigned int _dl_skip_args attribute_hidden |
698 | # ifndef DL_ARGV_NOT_RELRO |
699 | attribute_relro |
700 | # endif |
701 | ; |
702 | extern unsigned int _dl_skip_args_internal attribute_hidden |
703 | # ifndef DL_ARGV_NOT_RELRO |
704 | attribute_relro |
705 | # endif |
706 | ; |
707 | #endif |
708 | #define rtld_progname _dl_argv[0] |
709 | |
710 | /* Flag set at startup and cleared when the last initializer has run. */ |
711 | extern int _dl_starting_up; |
712 | weak_extern (_dl_starting_up) |
713 | rtld_hidden_proto (_dl_starting_up) |
714 | |
715 | /* Random data provided by the kernel. */ |
716 | extern void *_dl_random attribute_hidden attribute_relro; |
717 | |
718 | /* Write message on the debug file descriptor. The parameters are |
719 | interpreted as for a `printf' call. All the lines start with a |
720 | tag showing the PID. */ |
721 | extern void _dl_debug_printf (const char *fmt, ...) |
722 | __attribute__ ((__format__ (__printf__, 1, 2))) attribute_hidden; |
723 | |
724 | /* Write message on the debug file descriptor. The parameters are |
725 | interpreted as for a `printf' call. All the lines buf the first |
726 | start with a tag showing the PID. */ |
727 | extern void _dl_debug_printf_c (const char *fmt, ...) |
728 | __attribute__ ((__format__ (__printf__, 1, 2))) attribute_hidden; |
729 | |
730 | |
731 | /* Write a message on the specified descriptor FD. The parameters are |
732 | interpreted as for a `printf' call. */ |
733 | #if IS_IN (rtld) || !defined (SHARED) |
734 | extern void _dl_dprintf (int fd, const char *fmt, ...) |
735 | __attribute__ ((__format__ (__printf__, 2, 3))) |
736 | attribute_hidden; |
737 | #else |
738 | __attribute__ ((always_inline, __format__ (__printf__, 2, 3))) |
739 | static inline void |
740 | _dl_dprintf (int fd, const char *fmt, ...) |
741 | { |
742 | /* Use local declaration to avoid includign <stdio.h>. */ |
743 | extern int __dprintf(int fd, const char *format, ...) attribute_hidden; |
744 | __dprintf (fd, fmt, __builtin_va_arg_pack ()); |
745 | } |
746 | #endif |
747 | |
748 | /* Write a message on the specified descriptor standard output. The |
749 | parameters are interpreted as for a `printf' call. */ |
750 | #define _dl_printf(fmt, args...) \ |
751 | _dl_dprintf (STDOUT_FILENO, fmt, ##args) |
752 | |
753 | /* Write a message on the specified descriptor standard error. The |
754 | parameters are interpreted as for a `printf' call. */ |
755 | #define _dl_error_printf(fmt, args...) \ |
756 | _dl_dprintf (STDERR_FILENO, fmt, ##args) |
757 | |
758 | /* Write a message on the specified descriptor standard error and exit |
759 | the program. The parameters are interpreted as for a `printf' call. */ |
760 | #define _dl_fatal_printf(fmt, args...) \ |
761 | do \ |
762 | { \ |
763 | _dl_dprintf (STDERR_FILENO, fmt, ##args); \ |
764 | _exit (127); \ |
765 | } \ |
766 | while (1) |
767 | |
768 | |
769 | /* An exception raised by the _dl_signal_error function family and |
770 | caught by _dl_catch_error function family. Exceptions themselves |
771 | are copied as part of the raise operation, but the strings are |
772 | not. */ |
773 | struct dl_exception |
774 | { |
775 | const char *objname; |
776 | const char *errstring; |
777 | |
778 | /* This buffer typically stores both objname and errstring |
779 | above. */ |
780 | char *message_buffer; |
781 | }; |
782 | |
783 | /* Creates a new exception. This calls malloc; if allocation fails, |
784 | dummy values are inserted. OBJECT is the name of the problematical |
785 | shared object, or null if its a general problem. ERRSTRING is a |
786 | string describing the specific problem. */ |
787 | void _dl_exception_create (struct dl_exception *, const char *object, |
788 | const char *errstring) |
789 | __attribute__ ((nonnull (1, 3))); |
790 | rtld_hidden_proto (_dl_exception_create) |
791 | |
792 | /* Like _dl_exception_create, but create errstring from a format |
793 | string FMT. Currently, only "%s" and "%%" are supported as format |
794 | directives. */ |
795 | void _dl_exception_create_format (struct dl_exception *, const char *objname, |
796 | const char *fmt, ...) |
797 | __attribute__ ((nonnull (1, 3), format (printf, 3, 4))); |
798 | rtld_hidden_proto (_dl_exception_create_format) |
799 | |
800 | /* Deallocate the exception, freeing allocated buffers (if |
801 | possible). */ |
802 | void _dl_exception_free (struct dl_exception *) |
803 | __attribute__ ((nonnull (1))); |
804 | rtld_hidden_proto (_dl_exception_free) |
805 | |
806 | /* This function is called by all the internal dynamic linker |
807 | functions when they encounter an error. ERRCODE is either an |
808 | `errno' code or zero; it specifies the return value of |
809 | _dl_catch_error. OCCASION is included in the error message if the |
810 | process is terminated immediately. */ |
811 | void _dl_signal_exception (int errcode, struct dl_exception *, |
812 | const char *occasion) |
813 | __attribute__ ((__noreturn__)); |
814 | libc_hidden_proto (_dl_signal_exception) |
815 | |
816 | /* Like _dl_signal_exception, but creates the exception first. */ |
817 | extern void _dl_signal_error (int errcode, const char *object, |
818 | const char *occasion, const char *errstring) |
819 | __attribute__ ((__noreturn__)); |
820 | libc_hidden_proto (_dl_signal_error) |
821 | |
822 | /* Like _dl_signal_exception, but may return when called in the |
823 | context of _dl_receive_error. This is only used during ld.so |
824 | bootstrap. In static and profiled builds, this is equivalent to |
825 | _dl_signal_exception. */ |
826 | #if IS_IN (rtld) |
827 | extern void _dl_signal_cexception (int errcode, struct dl_exception *, |
828 | const char *occasion) attribute_hidden; |
829 | #else |
830 | __attribute__ ((always_inline)) |
831 | static inline void |
832 | _dl_signal_cexception (int errcode, struct dl_exception *exception, |
833 | const char *occasion) |
834 | { |
835 | _dl_signal_exception (errcode, exception, occasion); |
836 | } |
837 | #endif |
838 | |
839 | /* See _dl_signal_cexception above. */ |
840 | #if IS_IN (rtld) |
841 | extern void _dl_signal_cerror (int errcode, const char *object, |
842 | const char *occasion, const char *errstring) |
843 | attribute_hidden; |
844 | #else |
845 | __attribute__ ((always_inline)) |
846 | static inline void |
847 | _dl_signal_cerror (int errcode, const char *object, |
848 | const char *occasion, const char *errstring) |
849 | { |
850 | _dl_signal_error (errcode, object, occasion, errstring); |
851 | } |
852 | #endif |
853 | |
854 | /* Call OPERATE, receiving errors from `dl_signal_cerror'. Unlike |
855 | `_dl_catch_error' the operation is resumed after the OPERATE |
856 | function returns. |
857 | ARGS is passed as argument to OPERATE. */ |
858 | extern void _dl_receive_error (receiver_fct fct, void (*operate) (void *), |
859 | void *args) attribute_hidden; |
860 | |
861 | /* Call OPERATE, catching errors from `_dl_signal_error' and related |
862 | functions. If there is no error, *ERRSTRING is set to null. If |
863 | there is an error, *ERRSTRING is set to a string constructed from |
864 | the strings passed to _dl_signal_error, and the error code passed |
865 | is the return value and *OBJNAME is set to the object name which |
866 | experienced the problems. ERRSTRING if nonzero points to a |
867 | malloc'ed string which the caller has to free after use. ARGS is |
868 | passed as argument to OPERATE. MALLOCEDP is set to true only if |
869 | the returned string is allocated using the libc's malloc. */ |
870 | extern int _dl_catch_error (const char **objname, const char **errstring, |
871 | bool *mallocedp, void (*operate) (void *), |
872 | void *args); |
873 | libc_hidden_proto (_dl_catch_error) |
874 | |
875 | /* Call OPERATE (ARGS). If no error occurs, set *EXCEPTION to zero. |
876 | Otherwise, store a copy of the raised exception in *EXCEPTION, |
877 | which has to be freed by _dl_exception_free. As a special case, if |
878 | EXCEPTION is null, call OPERATE (ARGS) with exception handling |
879 | disabled (so that exceptions are fatal). */ |
880 | int _dl_catch_exception (struct dl_exception *exception, |
881 | void (*operate) (void *), void *args); |
882 | libc_hidden_proto (_dl_catch_exception) |
883 | |
884 | /* Open the shared object NAME and map in its segments. |
885 | LOADER's DT_RPATH is used in searching for NAME. |
886 | If the object is already opened, returns its existing map. */ |
887 | extern struct link_map *_dl_map_object (struct link_map *loader, |
888 | const char *name, |
889 | int type, int trace_mode, int mode, |
890 | Lmid_t nsid) attribute_hidden; |
891 | |
892 | /* Call _dl_map_object on the dependencies of MAP, and set up |
893 | MAP->l_searchlist. PRELOADS points to a vector of NPRELOADS previously |
894 | loaded objects that will be inserted into MAP->l_searchlist after MAP |
895 | but before its dependencies. */ |
896 | extern void _dl_map_object_deps (struct link_map *map, |
897 | struct link_map **preloads, |
898 | unsigned int npreloads, int trace_mode, |
899 | int open_mode) |
900 | attribute_hidden; |
901 | |
902 | /* Cache the locations of MAP's hash table. */ |
903 | extern void _dl_setup_hash (struct link_map *map) attribute_hidden; |
904 | |
905 | |
906 | /* Collect the directories in the search path for LOADER's dependencies. |
907 | The data structure is defined in <dlfcn.h>. If COUNTING is true, |
908 | SI->dls_cnt and SI->dls_size are set; if false, those must be as set |
909 | by a previous call with COUNTING set, and SI must point to SI->dls_size |
910 | bytes to be used in filling in the result. */ |
911 | extern void _dl_rtld_di_serinfo (struct link_map *loader, |
912 | Dl_serinfo *si, bool counting); |
913 | |
914 | |
915 | /* Search loaded objects' symbol tables for a definition of the symbol |
916 | referred to by UNDEF. *SYM is the symbol table entry containing the |
917 | reference; it is replaced with the defining symbol, and the base load |
918 | address of the defining object is returned. SYMBOL_SCOPE is a |
919 | null-terminated list of object scopes to search; each object's |
920 | l_searchlist (i.e. the segment of the dependency tree starting at that |
921 | object) is searched in turn. REFERENCE_NAME should name the object |
922 | containing the reference; it is used in error messages. |
923 | TYPE_CLASS describes the type of symbol we are looking for. */ |
924 | enum |
925 | { |
926 | /* If necessary add dependency between user and provider object. */ |
927 | DL_LOOKUP_ADD_DEPENDENCY = 1, |
928 | /* Return most recent version instead of default version for |
929 | unversioned lookup. */ |
930 | DL_LOOKUP_RETURN_NEWEST = 2, |
931 | /* Set if dl_lookup* called with GSCOPE lock held. */ |
932 | DL_LOOKUP_GSCOPE_LOCK = 4, |
933 | /* Set if dl_lookup is called for non-lazy relocation processing |
934 | from _dl_relocate_object in elf/dl-reloc.c. */ |
935 | DL_LOOKUP_FOR_RELOCATE = 8, |
936 | }; |
937 | |
938 | /* Lookup versioned symbol. */ |
939 | extern lookup_t _dl_lookup_symbol_x (const char *undef, |
940 | struct link_map *undef_map, |
941 | const ElfW(Sym) **sym, |
942 | struct r_scope_elem *symbol_scope[], |
943 | const struct r_found_version *version, |
944 | int type_class, int flags, |
945 | struct link_map *skip_map) |
946 | attribute_hidden; |
947 | |
948 | |
949 | /* Add the new link_map NEW to the end of the namespace list. */ |
950 | extern void _dl_add_to_namespace_list (struct link_map *new, Lmid_t nsid) |
951 | attribute_hidden; |
952 | |
953 | /* Allocate a `struct link_map' for a new object being loaded. */ |
954 | extern struct link_map *_dl_new_object (char *realname, const char *libname, |
955 | int type, struct link_map *loader, |
956 | int mode, Lmid_t nsid) |
957 | attribute_hidden; |
958 | |
959 | /* Relocate the given object (if it hasn't already been). |
960 | SCOPE is passed to _dl_lookup_symbol in symbol lookups. |
961 | If RTLD_LAZY is set in RELOC-MODE, don't relocate its PLT. */ |
962 | extern void _dl_relocate_object (struct link_map *map, |
963 | struct r_scope_elem *scope[], |
964 | int reloc_mode, int consider_profiling) |
965 | attribute_hidden; |
966 | |
967 | /* Protect PT_GNU_RELRO area. */ |
968 | extern void _dl_protect_relro (struct link_map *map) attribute_hidden; |
969 | |
970 | /* Call _dl_signal_error with a message about an unhandled reloc type. |
971 | TYPE is the result of ELFW(R_TYPE) (r_info), i.e. an R_<CPU>_* value. |
972 | PLT is nonzero if this was a PLT reloc; it just affects the message. */ |
973 | extern void _dl_reloc_bad_type (struct link_map *map, |
974 | unsigned int type, int plt) |
975 | attribute_hidden __attribute__ ((__noreturn__)); |
976 | |
977 | /* Resolve conflicts if prelinking. */ |
978 | extern void _dl_resolve_conflicts (struct link_map *l, |
979 | ElfW(Rela) *conflict, |
980 | ElfW(Rela) *conflictend) |
981 | attribute_hidden; |
982 | |
983 | /* Check the version dependencies of all objects available through |
984 | MAP. If VERBOSE print some more diagnostics. */ |
985 | extern int _dl_check_all_versions (struct link_map *map, int verbose, |
986 | int trace_mode) attribute_hidden; |
987 | |
988 | /* Check the version dependencies for MAP. If VERBOSE print some more |
989 | diagnostics. */ |
990 | extern int _dl_check_map_versions (struct link_map *map, int verbose, |
991 | int trace_mode) attribute_hidden; |
992 | |
993 | /* Initialize the object in SCOPE by calling the constructors with |
994 | ARGC, ARGV, and ENV as the parameters. */ |
995 | extern void _dl_init (struct link_map *main_map, int argc, char **argv, |
996 | char **env) attribute_hidden; |
997 | |
998 | /* Call the finalizer functions of all shared objects whose |
999 | initializer functions have completed. */ |
1000 | extern void _dl_fini (void) attribute_hidden; |
1001 | |
1002 | /* Sort array MAPS according to dependencies of the contained objects. */ |
1003 | extern void _dl_sort_maps (struct link_map **maps, unsigned int nmaps, |
1004 | char *used, bool for_fini) attribute_hidden; |
1005 | |
1006 | /* The dynamic linker calls this function before and having changing |
1007 | any shared object mappings. The `r_state' member of `struct r_debug' |
1008 | says what change is taking place. This function's address is |
1009 | the value of the `r_brk' member. */ |
1010 | extern void _dl_debug_state (void); |
1011 | rtld_hidden_proto (_dl_debug_state) |
1012 | |
1013 | /* Initialize `struct r_debug' if it has not already been done. The |
1014 | argument is the run-time load address of the dynamic linker, to be put |
1015 | in the `r_ldbase' member. Returns the address of the structure. */ |
1016 | extern struct r_debug *_dl_debug_initialize (ElfW(Addr) ldbase, Lmid_t ns) |
1017 | attribute_hidden; |
1018 | |
1019 | /* Initialize the basic data structure for the search paths. */ |
1020 | extern void _dl_init_paths (const char *library_path) attribute_hidden; |
1021 | |
1022 | /* Gather the information needed to install the profiling tables and start |
1023 | the timers. */ |
1024 | extern void _dl_start_profile (void) attribute_hidden; |
1025 | |
1026 | /* The actual functions used to keep book on the calls. */ |
1027 | extern void _dl_mcount (ElfW(Addr) frompc, ElfW(Addr) selfpc); |
1028 | rtld_hidden_proto (_dl_mcount) |
1029 | |
1030 | /* This function is simply a wrapper around the _dl_mcount function |
1031 | which does not require a FROMPC parameter since this is the |
1032 | calling function. */ |
1033 | extern void _dl_mcount_wrapper (void *selfpc); |
1034 | |
1035 | /* Show the members of the auxiliary array passed up from the kernel. */ |
1036 | extern void _dl_show_auxv (void) attribute_hidden; |
1037 | |
1038 | /* Return all environment variables starting with `LD_', one after the |
1039 | other. */ |
1040 | extern char *_dl_next_ld_env_entry (char ***position) attribute_hidden; |
1041 | |
1042 | /* Return an array with the names of the important hardware capabilities. */ |
1043 | extern const struct r_strlenpair *_dl_important_hwcaps (const char *platform, |
1044 | size_t paltform_len, |
1045 | size_t *sz, |
1046 | size_t *max_capstrlen) |
1047 | attribute_hidden; |
1048 | |
1049 | /* Look up NAME in ld.so.cache and return the file name stored there, |
1050 | or null if none is found. Caller must free returned string. */ |
1051 | extern char *_dl_load_cache_lookup (const char *name) attribute_hidden; |
1052 | |
1053 | /* If the system does not support MAP_COPY we cannot leave the file open |
1054 | all the time since this would create problems when the file is replaced. |
1055 | Therefore we provide this function to close the file and open it again |
1056 | once needed. */ |
1057 | extern void _dl_unload_cache (void) attribute_hidden; |
1058 | |
1059 | /* System-dependent function to read a file's whole contents in the |
1060 | most convenient manner available. *SIZEP gets the size of the |
1061 | file. On error MAP_FAILED is returned. */ |
1062 | extern void *_dl_sysdep_read_whole_file (const char *file, size_t *sizep, |
1063 | int prot) attribute_hidden; |
1064 | |
1065 | /* System-specific function to do initial startup for the dynamic linker. |
1066 | After this, file access calls and getenv must work. This is responsible |
1067 | for setting __libc_enable_secure if we need to be secure (e.g. setuid), |
1068 | and for setting _dl_argc and _dl_argv, and then calling _dl_main. */ |
1069 | extern ElfW(Addr) _dl_sysdep_start (void **start_argptr, |
1070 | void (*dl_main) (const ElfW(Phdr) *phdr, |
1071 | ElfW(Word) phnum, |
1072 | ElfW(Addr) *user_entry, |
1073 | ElfW(auxv_t) *auxv)) |
1074 | attribute_hidden; |
1075 | |
1076 | extern void _dl_sysdep_start_cleanup (void) attribute_hidden; |
1077 | |
1078 | |
1079 | /* Determine next available module ID. */ |
1080 | extern size_t _dl_next_tls_modid (void) attribute_hidden; |
1081 | |
1082 | /* Count the modules with TLS segments. */ |
1083 | extern size_t _dl_count_modids (void) attribute_hidden; |
1084 | |
1085 | /* Calculate offset of the TLS blocks in the static TLS block. */ |
1086 | extern void _dl_determine_tlsoffset (void) attribute_hidden; |
1087 | |
1088 | #ifndef SHARED |
1089 | /* Set up the TCB for statically linked applications. This is called |
1090 | early during startup because we always use TLS (for errno and the |
1091 | stack protector, among other things). */ |
1092 | void __libc_setup_tls (void); |
1093 | |
1094 | # if ENABLE_STATIC_PIE |
1095 | /* Relocate static executable with PIE. */ |
1096 | extern void _dl_relocate_static_pie (void) attribute_hidden; |
1097 | |
1098 | /* Get a pointer to _dl_main_map. */ |
1099 | extern struct link_map * _dl_get_dl_main_map (void) |
1100 | __attribute__ ((visibility ("hidden" ))); |
1101 | # else |
1102 | # define _dl_relocate_static_pie() |
1103 | # endif |
1104 | #endif |
1105 | |
1106 | /* Initialization of libpthread for statically linked applications. |
1107 | If libpthread is not linked in, this is an empty function. */ |
1108 | void __pthread_initialize_minimal (void) weak_function; |
1109 | |
1110 | /* Allocate memory for static TLS block (unless MEM is nonzero) and dtv. */ |
1111 | extern void *_dl_allocate_tls (void *mem); |
1112 | rtld_hidden_proto (_dl_allocate_tls) |
1113 | |
1114 | /* Get size and alignment requirements of the static TLS block. */ |
1115 | extern void _dl_get_tls_static_info (size_t *sizep, size_t *alignp); |
1116 | |
1117 | extern void _dl_allocate_static_tls (struct link_map *map) attribute_hidden; |
1118 | |
1119 | /* These are internal entry points to the two halves of _dl_allocate_tls, |
1120 | only used within rtld.c itself at startup time. */ |
1121 | extern void *_dl_allocate_tls_storage (void) attribute_hidden; |
1122 | extern void *_dl_allocate_tls_init (void *); |
1123 | rtld_hidden_proto (_dl_allocate_tls_init) |
1124 | |
1125 | /* Deallocate memory allocated with _dl_allocate_tls. */ |
1126 | extern void _dl_deallocate_tls (void *tcb, bool dealloc_tcb); |
1127 | rtld_hidden_proto (_dl_deallocate_tls) |
1128 | |
1129 | extern void _dl_nothread_init_static_tls (struct link_map *) attribute_hidden; |
1130 | |
1131 | /* Find origin of the executable. */ |
1132 | extern const char *_dl_get_origin (void) attribute_hidden; |
1133 | |
1134 | /* Count DSTs. */ |
1135 | extern size_t _dl_dst_count (const char *name) attribute_hidden; |
1136 | |
1137 | /* Substitute DST values. */ |
1138 | extern char *_dl_dst_substitute (struct link_map *l, const char *name, |
1139 | char *result) attribute_hidden; |
1140 | |
1141 | /* Open the shared object NAME, relocate it, and run its initializer if it |
1142 | hasn't already been run. MODE is as for `dlopen' (see <dlfcn.h>). If |
1143 | the object is already opened, returns its existing map. */ |
1144 | extern void *_dl_open (const char *name, int mode, const void *caller, |
1145 | Lmid_t nsid, int argc, char *argv[], char *env[]) |
1146 | attribute_hidden; |
1147 | |
1148 | /* Free or queue for freeing scope OLD. If other threads might be |
1149 | in the middle of _dl_fixup, _dl_profile_fixup or dl*sym using the |
1150 | old scope, OLD can't be freed until no thread is using it. */ |
1151 | extern int _dl_scope_free (void *) attribute_hidden; |
1152 | |
1153 | |
1154 | /* Add module to slot information data. If DO_ADD is false, only the |
1155 | required memory is allocated. Must be called with GL |
1156 | (dl_load_lock) acquired. If the function has already been called |
1157 | for the link map L with !do_add, then this function will not raise |
1158 | an exception, otherwise it is possible that it encounters a memory |
1159 | allocation failure. */ |
1160 | extern void _dl_add_to_slotinfo (struct link_map *l, bool do_add) |
1161 | attribute_hidden; |
1162 | |
1163 | /* Update slot information data for at least the generation of the |
1164 | module with the given index. */ |
1165 | extern struct link_map *_dl_update_slotinfo (unsigned long int req_modid) |
1166 | attribute_hidden; |
1167 | |
1168 | /* Look up the module's TLS block as for __tls_get_addr, |
1169 | but never touch anything. Return null if it's not allocated yet. */ |
1170 | extern void *_dl_tls_get_addr_soft (struct link_map *l) attribute_hidden; |
1171 | |
1172 | extern int _dl_addr_inside_object (struct link_map *l, const ElfW(Addr) addr) |
1173 | attribute_hidden; |
1174 | |
1175 | /* Show show of an object. */ |
1176 | extern void _dl_show_scope (struct link_map *new, int from) |
1177 | attribute_hidden; |
1178 | |
1179 | extern struct link_map *_dl_find_dso_for_object (const ElfW(Addr) addr); |
1180 | rtld_hidden_proto (_dl_find_dso_for_object) |
1181 | |
1182 | /* Initialization which is normally done by the dynamic linker. */ |
1183 | extern void _dl_non_dynamic_init (void) |
1184 | attribute_hidden; |
1185 | |
1186 | /* Used by static binaries to check the auxiliary vector. */ |
1187 | extern void _dl_aux_init (ElfW(auxv_t) *av) |
1188 | attribute_hidden; |
1189 | |
1190 | /* Return true if the ld.so copy in this namespace is actually active |
1191 | and working. If false, the dl_open/dlfcn hooks have to be used to |
1192 | call into the outer dynamic linker (which happens after static |
1193 | dlopen). */ |
1194 | #ifdef SHARED |
1195 | static inline bool |
1196 | rtld_active (void) |
1197 | { |
1198 | /* The default-initialized variable does not have a non-zero |
1199 | dl_init_all_dirs member, so this allows us to recognize an |
1200 | initialized and active ld.so copy. */ |
1201 | return GLRO(dl_init_all_dirs) != NULL; |
1202 | } |
1203 | |
1204 | static inline struct auditstate * |
1205 | link_map_audit_state (struct link_map *l, size_t index) |
1206 | { |
1207 | if (l == &GL (dl_rtld_map)) |
1208 | /* The auditstate array is stored separately. */ |
1209 | return &GL (dl_rtld_auditstate) [index]; |
1210 | else |
1211 | { |
1212 | /* The auditstate array follows the link map in memory. */ |
1213 | struct auditstate *base = (struct auditstate *) (l + 1); |
1214 | return &base[index]; |
1215 | } |
1216 | } |
1217 | #endif /* SHARED */ |
1218 | |
1219 | __END_DECLS |
1220 | |
1221 | #endif /* ldsodefs.h */ |
1222 | |