Add x32 support to dynamic linker audit
[glibc.git] / sysdeps / generic / ldsodefs.h
blobd4cbabab51fd6aa883af5a9273678e5246b23a36
1 /* Run-time dynamic linker data structures for loaded ELF shared objects.
2 Copyright (C) 1995-2009, 2010, 2011, 2012 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
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.
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.
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 <http://www.gnu.org/licenses/>. */
19 #ifndef _LDSODEFS_H
20 #define _LDSODEFS_H 1
22 #include <features.h>
24 #include <stdbool.h>
25 #define __need_size_t
26 #define __need_NULL
27 #include <stddef.h>
28 #include <string.h>
30 #include <elf.h>
31 #include <dlfcn.h>
32 #include <fpu_control.h>
33 #include <sys/mman.h>
34 #include <link.h>
35 #include <dl-lookupcfg.h>
36 #include <dl-sysdep.h>
37 #include <bits/libc-lock.h>
38 #include <hp-timing.h>
39 #include <tls.h>
40 #include <kernel-features.h>
42 __BEGIN_DECLS
44 /* We use this macro to refer to ELF types independent of the native wordsize.
45 `ElfW(TYPE)' is used in place of `Elf32_TYPE' or `Elf64_TYPE'. */
46 #define ELFW(type) _ElfW (ELF, __ELF_NATIVE_CLASS, type)
48 /* All references to the value of l_info[DT_PLTGOT],
49 l_info[DT_STRTAB], l_info[DT_SYMTAB], l_info[DT_RELA],
50 l_info[DT_REL], l_info[DT_JMPREL], and l_info[VERSYMIDX (DT_VERSYM)]
51 have to be accessed via the D_PTR macro. The macro is needed since for
52 most architectures the entry is already relocated - but for some not
53 and we need to relocate at access time. */
54 #ifdef DL_RO_DYN_SECTION
55 # define D_PTR(map, i) ((map)->i->d_un.d_ptr + (map)->l_addr)
56 #else
57 # define D_PTR(map, i) (map)->i->d_un.d_ptr
58 #endif
60 /* Result of the lookup functions and how to retrieve the base address. */
61 typedef struct link_map *lookup_t;
62 #define LOOKUP_VALUE(map) map
63 #define LOOKUP_VALUE_ADDRESS(map) ((map) ? (map)->l_addr : 0)
65 /* On some architectures a pointer to a function is not just a pointer
66 to the actual code of the function but rather an architecture
67 specific descriptor. */
68 #ifndef ELF_FUNCTION_PTR_IS_SPECIAL
69 # define DL_SYMBOL_ADDRESS(map, ref) \
70 (void *) (LOOKUP_VALUE_ADDRESS (map) + ref->st_value)
71 # define DL_LOOKUP_ADDRESS(addr) ((ElfW(Addr)) (addr))
72 # define DL_DT_INIT_ADDRESS(map, start) (start)
73 # define DL_DT_FINI_ADDRESS(map, start) (start)
74 #endif
76 /* On some architectures dladdr can't use st_size of all symbols this way. */
77 #define DL_ADDR_SYM_MATCH(L, SYM, MATCHSYM, ADDR) \
78 ((ADDR) >= (L)->l_addr + (SYM)->st_value \
79 && ((((SYM)->st_shndx == SHN_UNDEF || (SYM)->st_size == 0) \
80 && (ADDR) == (L)->l_addr + (SYM)->st_value) \
81 || (ADDR) < (L)->l_addr + (SYM)->st_value + (SYM)->st_size) \
82 && ((MATCHSYM) == NULL || (MATCHSYM)->st_value < (SYM)->st_value))
84 /* Unmap a loaded object, called by _dl_close (). */
85 #ifndef DL_UNMAP_IS_SPECIAL
86 # define DL_UNMAP(map) \
87 __munmap ((void *) (map)->l_map_start, \
88 (map)->l_map_end - (map)->l_map_start)
89 #endif
91 /* By default we do not need special support to initialize DSOs loaded
92 by statically linked binaries. */
93 #ifndef DL_STATIC_INIT
94 # define DL_STATIC_INIT(map)
95 #endif
97 /* Reloc type classes as returned by elf_machine_type_class().
98 ELF_RTYPE_CLASS_PLT means this reloc should not be satisfied by
99 some PLT symbol, ELF_RTYPE_CLASS_COPY means this reloc should not be
100 satisfied by any symbol in the executable. Some architectures do
101 not support copy relocations. In this case we define the macro to
102 zero so that the code for handling them gets automatically optimized
103 out. */
104 #define ELF_RTYPE_CLASS_PLT 1
105 #ifndef DL_NO_COPY_RELOCS
106 # define ELF_RTYPE_CLASS_COPY 2
107 #else
108 # define ELF_RTYPE_CLASS_COPY 0
109 #endif
111 /* ELF uses the PF_x macros to specify the segment permissions, mmap
112 uses PROT_xxx. In most cases the three macros have the values 1, 2,
113 and 3 but not in a matching order. The following macros allows
114 converting from the PF_x values to PROT_xxx values. */
115 #define PF_TO_PROT \
116 ((PROT_READ << (PF_R * 4)) \
117 | (PROT_WRITE << (PF_W * 4)) \
118 | (PROT_EXEC << (PF_X * 4)) \
119 | ((PROT_READ | PROT_WRITE) << ((PF_R | PF_W) * 4)) \
120 | ((PROT_READ | PROT_EXEC) << ((PF_R | PF_X) * 4)) \
121 | ((PROT_WRITE | PROT_EXEC) << (PF_W | PF_X) * 4) \
122 | ((PROT_READ | PROT_WRITE | PROT_EXEC) << ((PF_R | PF_W | PF_X) * 4)))
125 /* For the version handling we need an array with only names and their
126 hash values. */
127 struct r_found_version
129 const char *name;
130 ElfW(Word) hash;
132 int hidden;
133 const char *filename;
136 /* We want to cache information about the searches for shared objects. */
138 enum r_dir_status { unknown, nonexisting, existing };
140 struct r_search_path_elem
142 /* This link is only used in the `all_dirs' member of `r_search_path'. */
143 struct r_search_path_elem *next;
145 /* Strings saying where the definition came from. */
146 const char *what;
147 const char *where;
149 /* Basename for this search path element. The string must end with
150 a slash character. */
151 const char *dirname;
152 size_t dirnamelen;
154 enum r_dir_status status[0];
157 struct r_strlenpair
159 const char *str;
160 size_t len;
164 /* A data structure for a simple single linked list of strings. */
165 struct libname_list
167 const char *name; /* Name requested (before search). */
168 struct libname_list *next; /* Link to next name for this object. */
169 int dont_free; /* Flag whether this element should be freed
170 if the object is not entirely unloaded. */
174 /* Bit masks for the objects which valid callers can come from to
175 functions with restricted interface. */
176 enum allowmask
178 allow_libc = 1,
179 allow_libdl = 2,
180 allow_libpthread = 4,
181 allow_ldso = 8
185 /* Type for list of auditing interfaces. */
186 struct La_i86_regs;
187 struct La_i86_retval;
188 struct La_x86_64_regs;
189 struct La_x86_64_retval;
190 struct La_ppc32_regs;
191 struct La_ppc32_retval;
192 struct La_ppc64_regs;
193 struct La_ppc64_retval;
194 struct La_sh_regs;
195 struct La_sh_retval;
196 struct La_s390_32_regs;
197 struct La_s390_32_retval;
198 struct La_s390_64_regs;
199 struct La_s390_64_retval;
200 struct La_sparc32_regs;
201 struct La_sparc32_retval;
202 struct La_sparc64_regs;
203 struct La_sparc64_retval;
205 struct audit_ifaces
207 void (*activity) (uintptr_t *, unsigned int);
208 char *(*objsearch) (const char *, uintptr_t *, unsigned int);
209 unsigned int (*objopen) (struct link_map *, Lmid_t, uintptr_t *);
210 void (*preinit) (uintptr_t *);
211 union
213 uintptr_t (*symbind32) (Elf32_Sym *, unsigned int, uintptr_t *,
214 uintptr_t *, unsigned int *, const char *);
215 uintptr_t (*symbind64) (Elf64_Sym *, unsigned int, uintptr_t *,
216 uintptr_t *, unsigned int *, const char *);
218 union
220 Elf32_Addr (*i86_gnu_pltenter) (Elf32_Sym *, unsigned int, uintptr_t *,
221 uintptr_t *, struct La_i86_regs *,
222 unsigned int *, const char *name,
223 long int *framesizep);
224 Elf64_Addr (*x86_64_gnu_pltenter) (Elf64_Sym *, unsigned int, uintptr_t *,
225 uintptr_t *, struct La_x86_64_regs *,
226 unsigned int *, const char *name,
227 long int *framesizep);
228 Elf32_Addr (*x32_gnu_pltenter) (Elf32_Sym *, unsigned int, uintptr_t *,
229 uintptr_t *, struct La_x32_regs *,
230 unsigned int *, const char *name,
231 long int *framesizep);
232 Elf32_Addr (*ppc32_gnu_pltenter) (Elf32_Sym *, unsigned int, uintptr_t *,
233 uintptr_t *, struct La_ppc32_regs *,
234 unsigned int *, const char *name,
235 long int *framesizep);
236 Elf64_Addr (*ppc64_gnu_pltenter) (Elf64_Sym *, unsigned int, uintptr_t *,
237 uintptr_t *, struct La_ppc64_regs *,
238 unsigned int *, const char *name,
239 long int *framesizep);
240 uintptr_t (*sh_gnu_pltenter) (Elf32_Sym *, unsigned int, uintptr_t *,
241 uintptr_t *, const struct La_sh_regs *,
242 unsigned int *, const char *name,
243 long int *framesizep);
244 Elf32_Addr (*s390_32_gnu_pltenter) (Elf32_Sym *, unsigned int, uintptr_t *,
245 uintptr_t *, struct La_s390_32_regs *,
246 unsigned int *, const char *name,
247 long int *framesizep);
248 Elf64_Addr (*s390_64_gnu_pltenter) (Elf64_Sym *, unsigned int, uintptr_t *,
249 uintptr_t *, struct La_s390_64_regs *,
250 unsigned int *, const char *name,
251 long int *framesizep);
252 Elf32_Addr (*sparc32_gnu_pltenter) (Elf32_Sym *, unsigned int,
253 uintptr_t *, uintptr_t *,
254 const struct La_sparc32_regs *,
255 unsigned int *, const char *name,
256 long int *framesizep);
257 Elf64_Addr (*sparc64_gnu_pltenter) (Elf64_Sym *, unsigned int,
258 uintptr_t *, uintptr_t *,
259 const struct La_sparc64_regs *,
260 unsigned int *, const char *name,
261 long int *framesizep);
262 #ifdef ARCH_PLTENTER_MEMBERS
263 ARCH_PLTENTER_MEMBERS;
264 #endif
266 union
268 unsigned int (*i86_gnu_pltexit) (Elf32_Sym *, unsigned int, uintptr_t *,
269 uintptr_t *, const struct La_i86_regs *,
270 struct La_i86_retval *, const char *);
271 unsigned int (*x86_64_gnu_pltexit) (Elf64_Sym *, unsigned int, uintptr_t *,
272 uintptr_t *,
273 const struct La_x86_64_regs *,
274 struct La_x86_64_retval *,
275 const char *);
276 unsigned int (*x32_gnu_pltexit) (Elf32_Sym *, unsigned int, uintptr_t *,
277 uintptr_t *,
278 const struct La_x32_regs *,
279 struct La_x86_64_retval *,
280 const char *);
281 unsigned int (*ppc32_gnu_pltexit) (Elf32_Sym *, unsigned int, uintptr_t *,
282 uintptr_t *,
283 const struct La_ppc32_regs *,
284 struct La_ppc32_retval *, const char *);
285 unsigned int (*ppc64_gnu_pltexit) (Elf64_Sym *, unsigned int, uintptr_t *,
286 uintptr_t *,
287 const struct La_ppc64_regs *,
288 struct La_ppc64_retval *, const char *);
289 unsigned int (*sh_gnu_pltexit) (Elf32_Sym *, unsigned int, uintptr_t *,
290 uintptr_t *, const struct La_sh_regs *,
291 struct La_sh_retval *, const char *);
292 unsigned int (*s390_32_gnu_pltexit) (Elf32_Sym *, unsigned int,
293 uintptr_t *, uintptr_t *,
294 const struct La_s390_32_regs *,
295 struct La_s390_32_retval *,
296 const char *);
297 unsigned int (*s390_64_gnu_pltexit) (Elf64_Sym *, unsigned int,
298 uintptr_t *, uintptr_t *,
299 const struct La_s390_64_regs *,
300 struct La_s390_64_retval *,
301 const char *);
302 unsigned int (*sparc32_gnu_pltexit) (Elf32_Sym *, unsigned int,
303 uintptr_t *, uintptr_t *,
304 const struct La_sparc32_regs *,
305 struct La_sparc32_retval *,
306 const char *);
307 unsigned int (*sparc64_gnu_pltexit) (Elf64_Sym *, unsigned int,
308 uintptr_t *, uintptr_t *,
309 const struct La_sparc32_regs *,
310 struct La_sparc32_retval *,
311 const char *);
312 #ifdef ARCH_PLTEXIT_MEMBERS
313 ARCH_PLTEXIT_MEMBERS;
314 #endif
316 unsigned int (*objclose) (uintptr_t *);
318 struct audit_ifaces *next;
322 /* Test whether given NAME matches any of the names of the given object. */
323 extern int _dl_name_match_p (const char *__name, const struct link_map *__map)
324 internal_function;
326 /* Compute next higher prime number. */
327 extern unsigned long int _dl_higher_prime_number (unsigned long int n)
328 internal_function;
330 /* Function used as argument for `_dl_receive_error' function. The
331 arguments are the error code, error string, and the objname the
332 error occurred in. */
333 typedef void (*receiver_fct) (int, const char *, const char *);
335 /* Internal functions of the run-time dynamic linker.
336 These can be accessed if you link again the dynamic linker
337 as a shared library, as in `-lld' or `/lib/ld.so' explicitly;
338 but are not normally of interest to user programs.
340 The `-ldl' library functions in <dlfcn.h> provide a simple
341 user interface to run-time dynamic linking. */
344 #ifndef SHARED
345 # define EXTERN extern
346 # define GL(name) _##name
347 #else
348 # define EXTERN
349 # ifdef IS_IN_rtld
350 # define GL(name) _rtld_local._##name
351 # else
352 # define GL(name) _rtld_global._##name
353 # endif
354 struct rtld_global
356 #endif
357 /* Don't change the order of the following elements. 'dl_loaded'
358 must remain the first element. Forever. */
360 /* Non-shared code has no support for multiple namespaces. */
361 #ifdef SHARED
362 # define DL_NNS 16
363 #else
364 # define DL_NNS 1
365 #endif
366 EXTERN struct link_namespaces
368 /* A pointer to the map for the main map. */
369 struct link_map *_ns_loaded;
370 /* Number of object in the _dl_loaded list. */
371 unsigned int _ns_nloaded;
372 /* Direct pointer to the searchlist of the main object. */
373 struct r_scope_elem *_ns_main_searchlist;
374 /* This is zero at program start to signal that the global scope map is
375 allocated by rtld. Later it keeps the size of the map. It might be
376 reset if in _dl_close if the last global object is removed. */
377 size_t _ns_global_scope_alloc;
378 /* Search table for unique objects. */
379 struct unique_sym_table
381 __rtld_lock_recursive_t lock;
382 struct unique_sym
384 uint32_t hashval;
385 const char *name;
386 const ElfW(Sym) *sym;
387 const struct link_map *map;
388 } *entries;
389 size_t size;
390 size_t n_elements;
391 void (*free) (void *);
392 } _ns_unique_sym_table;
393 /* Keep track of changes to each namespace' list. */
394 struct r_debug _ns_debug;
395 } _dl_ns[DL_NNS];
396 /* One higher than index of last used namespace. */
397 EXTERN size_t _dl_nns;
399 /* During the program run we must not modify the global data of
400 loaded shared object simultanously in two threads. Therefore we
401 protect `_dl_open' and `_dl_close' in dl-close.c.
403 This must be a recursive lock since the initializer function of
404 the loaded object might as well require a call to this function.
405 At this time it is not anymore a problem to modify the tables. */
406 __rtld_lock_define_recursive (EXTERN, _dl_load_lock)
407 /* This lock is used to keep __dl_iterate_phdr from inspecting the
408 list of loaded objects while an object is added to or removed
409 from that list. */
410 __rtld_lock_define_recursive (EXTERN, _dl_load_write_lock)
412 /* Incremented whenever something may have been added to dl_loaded. */
413 EXTERN unsigned long long _dl_load_adds;
415 /* The object to be initialized first. */
416 EXTERN struct link_map *_dl_initfirst;
418 #if HP_TIMING_AVAIL || HP_SMALL_TIMING_AVAIL
419 /* Start time on CPU clock. */
420 EXTERN hp_timing_t _dl_cpuclock_offset;
421 #endif
423 /* Map of shared object to be profiled. */
424 EXTERN struct link_map *_dl_profile_map;
426 /* Counters for the number of relocations performed. */
427 EXTERN unsigned long int _dl_num_relocations;
428 EXTERN unsigned long int _dl_num_cache_relocations;
430 /* List of search directories. */
431 EXTERN struct r_search_path_elem *_dl_all_dirs;
433 #ifdef _LIBC_REENTRANT
434 EXTERN void **(*_dl_error_catch_tsd) (void) __attribute__ ((const));
435 #endif
437 /* Structure describing the dynamic linker itself. We need to
438 reserve memory for the data the audit libraries need. */
439 EXTERN struct link_map _dl_rtld_map;
440 #ifdef SHARED
441 struct auditstate audit_data[DL_NNS];
442 #endif
444 #if defined SHARED && defined _LIBC_REENTRANT \
445 && defined __rtld_lock_default_lock_recursive
446 EXTERN void (*_dl_rtld_lock_recursive) (void *);
447 EXTERN void (*_dl_rtld_unlock_recursive) (void *);
448 #endif
450 /* If loading a shared object requires that we make the stack executable
451 when it was not, we do it by calling this function.
452 It returns an errno code or zero on success. */
453 EXTERN int (*_dl_make_stack_executable_hook) (void **) internal_function;
455 /* Prevailing state of the stack, PF_X indicating it's executable. */
456 EXTERN ElfW(Word) _dl_stack_flags;
458 /* Flag signalling whether there are gaps in the module ID allocation. */
459 EXTERN bool _dl_tls_dtv_gaps;
460 /* Highest dtv index currently needed. */
461 EXTERN size_t _dl_tls_max_dtv_idx;
462 /* Information about the dtv slots. */
463 EXTERN struct dtv_slotinfo_list
465 size_t len;
466 struct dtv_slotinfo_list *next;
467 struct dtv_slotinfo
469 size_t gen;
470 struct link_map *map;
471 } slotinfo[0];
472 } *_dl_tls_dtv_slotinfo_list;
473 /* Number of modules in the static TLS block. */
474 EXTERN size_t _dl_tls_static_nelem;
475 /* Size of the static TLS block. */
476 EXTERN size_t _dl_tls_static_size;
477 /* Size actually allocated in the static TLS block. */
478 EXTERN size_t _dl_tls_static_used;
479 /* Alignment requirement of the static TLS block. */
480 EXTERN size_t _dl_tls_static_align;
482 /* Number of additional entries in the slotinfo array of each slotinfo
483 list element. A large number makes it almost certain take we never
484 have to iterate beyond the first element in the slotinfo list. */
485 #define TLS_SLOTINFO_SURPLUS (62)
487 /* Number of additional slots in the dtv allocated. */
488 #define DTV_SURPLUS (14)
490 /* Initial dtv of the main thread, not allocated with normal malloc. */
491 EXTERN void *_dl_initial_dtv;
492 /* Generation counter for the dtv. */
493 EXTERN size_t _dl_tls_generation;
495 EXTERN void (*_dl_init_static_tls) (struct link_map *);
497 EXTERN void (*_dl_wait_lookup_done) (void);
499 /* Scopes to free after next THREAD_GSCOPE_WAIT (). */
500 EXTERN struct dl_scope_free_list
502 size_t count;
503 void *list[50];
504 } *_dl_scope_free_list;
505 #ifdef SHARED
507 # define __rtld_global_attribute__
508 # ifdef IS_IN_rtld
509 # ifdef HAVE_SDATA_SECTION
510 # define __rtld_local_attribute__ \
511 __attribute__ ((visibility ("hidden"), section (".sdata")))
512 # undef __rtld_global_attribute__
513 # define __rtld_global_attribute__ __attribute__ ((section (".sdata")))
514 # else
515 # define __rtld_local_attribute__ __attribute__ ((visibility ("hidden")))
516 # endif
517 extern struct rtld_global _rtld_local __rtld_local_attribute__;
518 # undef __rtld_local_attribute__
519 # endif
520 extern struct rtld_global _rtld_global __rtld_global_attribute__;
521 # undef __rtld_global_attribute__
522 #endif
524 #ifndef SHARED
525 # define GLRO(name) _##name
526 #else
527 # ifdef IS_IN_rtld
528 # define GLRO(name) _rtld_local_ro._##name
529 # else
530 # define GLRO(name) _rtld_global_ro._##name
531 # endif
532 struct rtld_global_ro
534 #endif
536 /* If nonzero the appropriate debug information is printed. */
537 EXTERN int _dl_debug_mask;
538 #define DL_DEBUG_LIBS (1 << 0)
539 #define DL_DEBUG_IMPCALLS (1 << 1)
540 #define DL_DEBUG_BINDINGS (1 << 2)
541 #define DL_DEBUG_SYMBOLS (1 << 3)
542 #define DL_DEBUG_VERSIONS (1 << 4)
543 #define DL_DEBUG_RELOC (1 << 5)
544 #define DL_DEBUG_FILES (1 << 6)
545 #define DL_DEBUG_STATISTICS (1 << 7)
546 #define DL_DEBUG_UNUSED (1 << 8)
547 #define DL_DEBUG_SCOPES (1 << 9)
548 /* These two are used only internally. */
549 #define DL_DEBUG_HELP (1 << 10)
550 #define DL_DEBUG_PRELINK (1 << 11)
552 /* OS version. */
553 EXTERN unsigned int _dl_osversion;
554 /* Platform name. */
555 EXTERN const char *_dl_platform;
556 EXTERN size_t _dl_platformlen;
558 /* Cached value of `getpagesize ()'. */
559 EXTERN size_t _dl_pagesize;
561 /* Copy of the content of `_dl_main_searchlist' at startup time. */
562 EXTERN struct r_scope_elem _dl_initial_searchlist;
564 /* CLK_TCK as reported by the kernel. */
565 EXTERN int _dl_clktck;
567 /* If nonzero print warnings messages. */
568 EXTERN int _dl_verbose;
570 /* File descriptor to write debug messages to. */
571 EXTERN int _dl_debug_fd;
573 /* Do we do lazy relocations? */
574 EXTERN int _dl_lazy;
576 /* Nonzero if runtime lookups should not update the .got/.plt. */
577 EXTERN int _dl_bind_not;
579 /* Nonzero if references should be treated as weak during runtime
580 linking. */
581 EXTERN int _dl_dynamic_weak;
583 /* Default floating-point control word. */
584 EXTERN fpu_control_t _dl_fpu_control;
586 /* Expected cache ID. */
587 EXTERN int _dl_correct_cache_id;
589 /* Mask for hardware capabilities that are available. */
590 EXTERN uint64_t _dl_hwcap;
592 /* Mask for important hardware capabilities we honour. */
593 EXTERN uint64_t _dl_hwcap_mask;
595 /* Get architecture specific definitions. */
596 #define PROCINFO_DECL
597 #ifndef PROCINFO_CLASS
598 # define PROCINFO_CLASS EXTERN
599 #endif
600 #include <dl-procinfo.c>
602 /* Names of shared object for which the RPATH should be ignored. */
603 EXTERN const char *_dl_inhibit_rpath;
605 /* Location of the binary. */
606 EXTERN const char *_dl_origin_path;
608 /* -1 if the dynamic linker should honor library load bias,
609 0 if not, -2 use the default (honor biases for normal
610 binaries, don't honor for PIEs). */
611 EXTERN ElfW(Addr) _dl_use_load_bias;
613 /* Name of the shared object to be profiled (if any). */
614 EXTERN const char *_dl_profile;
615 /* Filename of the output file. */
616 EXTERN const char *_dl_profile_output;
617 /* Name of the object we want to trace the prelinking. */
618 EXTERN const char *_dl_trace_prelink;
619 /* Map of shared object to be prelink traced. */
620 EXTERN struct link_map *_dl_trace_prelink_map;
622 /* All search directories defined at startup. */
623 EXTERN struct r_search_path_elem *_dl_init_all_dirs;
625 #if HP_TIMING_AVAIL || HP_SMALL_TIMING_AVAIL
626 /* Overhead of a high-precision timing measurement. */
627 EXTERN hp_timing_t _dl_hp_timing_overhead;
628 #endif
630 #ifdef NEED_DL_SYSINFO
631 /* Syscall handling improvements. This is very specific to x86. */
632 EXTERN uintptr_t _dl_sysinfo;
633 #endif
635 #if defined NEED_DL_SYSINFO || defined NEED_DL_SYSINFO_DSO
636 /* The vsyscall page is a virtual DSO pre-mapped by the kernel.
637 This points to its ELF header. */
638 EXTERN const ElfW(Ehdr) *_dl_sysinfo_dso;
640 /* At startup time we set up the normal DSO data structure for it,
641 and this points to it. */
642 EXTERN struct link_map *_dl_sysinfo_map;
643 #endif
645 #ifdef SHARED
646 /* We add a function table to _rtld_global which is then used to
647 call the function instead of going through the PLT. The result
648 is that we can avoid exporting the functions and we do not jump
649 PLT relocations in libc.so. */
650 void (*_dl_debug_printf) (const char *, ...)
651 __attribute__ ((__format__ (__printf__, 1, 2)));
652 int (internal_function *_dl_catch_error) (const char **, const char **,
653 bool *, void (*) (void *), void *);
654 void (internal_function *_dl_signal_error) (int, const char *, const char *,
655 const char *);
656 void (*_dl_mcount) (ElfW(Addr) frompc, ElfW(Addr) selfpc);
657 lookup_t (internal_function *_dl_lookup_symbol_x) (const char *,
658 struct link_map *,
659 const ElfW(Sym) **,
660 struct r_scope_elem *[],
661 const struct r_found_version *,
662 int, int,
663 struct link_map *);
664 int (*_dl_check_caller) (const void *, enum allowmask);
665 void *(*_dl_open) (const char *file, int mode, const void *caller_dlopen,
666 Lmid_t nsid, int argc, char *argv[], char *env[]);
667 void (*_dl_close) (void *map);
668 void *(*_dl_tls_get_addr_soft) (struct link_map *);
669 #ifdef HAVE_DL_DISCOVER_OSVERSION
670 int (*_dl_discover_osversion) (void);
671 #endif
673 /* List of auditing interfaces. */
674 struct audit_ifaces *_dl_audit;
675 unsigned int _dl_naudit;
677 /* 0 if internal pointer values should not be guarded, 1 if they should. */
678 EXTERN int _dl_pointer_guard;
680 # define __rtld_global_attribute__
681 # ifdef IS_IN_rtld
682 # define __rtld_local_attribute__ __attribute__ ((visibility ("hidden")))
683 extern struct rtld_global_ro _rtld_local_ro
684 attribute_relro __rtld_local_attribute__;
685 extern struct rtld_global_ro _rtld_global_ro
686 attribute_relro __rtld_global_attribute__;
687 # undef __rtld_local_attribute__
688 # else
689 /* We cheat a bit here. We declare the variable as as const even
690 though it is at startup. */
691 extern const struct rtld_global_ro _rtld_global_ro
692 attribute_relro __rtld_global_attribute__;
693 # endif
694 # undef __rtld_global_attribute__
695 #endif
696 #undef EXTERN
698 #ifdef IS_IN_rtld
699 /* This is the initial value of GL(dl_error_catch_tsd).
700 A non-TLS libpthread will change it. */
701 extern void **_dl_initial_error_catch_tsd (void) __attribute__ ((const))
702 attribute_hidden;
703 #endif
705 /* This is the initial value of GL(dl_make_stack_executable_hook).
706 A threads library can change it. */
707 extern int _dl_make_stack_executable (void **stack_endp) internal_function;
708 rtld_hidden_proto (_dl_make_stack_executable)
710 /* Variable pointing to the end of the stack (or close to it). This value
711 must be constant over the runtime of the application. Some programs
712 might use the variable which results in copy relocations on some
713 platforms. But this does not matter, ld.so can always use the local
714 copy. */
715 extern void *__libc_stack_end attribute_relro;
716 rtld_hidden_proto (__libc_stack_end)
718 /* Parameters passed to the dynamic linker. */
719 extern int _dl_argc attribute_hidden attribute_relro;
720 extern char **_dl_argv
721 #ifndef DL_ARGV_NOT_RELRO
722 attribute_relro
723 #endif
725 #ifdef IS_IN_rtld
726 extern char **_dl_argv_internal attribute_hidden
727 # ifndef DL_ARGV_NOT_RELRO
728 attribute_relro
729 # endif
731 # define rtld_progname (INTUSE(_dl_argv)[0])
732 #else
733 # define rtld_progname _dl_argv[0]
734 #endif
736 /* Flag set at startup and cleared when the last initializer has run. */
737 extern int _dl_starting_up;
738 weak_extern (_dl_starting_up)
739 #ifdef IS_IN_rtld
740 extern int _dl_starting_up_internal attribute_hidden;
741 #endif
743 /* Random data provided by the kernel. */
744 extern void *_dl_random attribute_hidden attribute_relro;
746 /* OS-dependent function to open the zero-fill device. */
747 extern int _dl_sysdep_open_zero_fill (void); /* dl-sysdep.c */
750 /* Write message on the debug file descriptor. The parameters are
751 interpreted as for a `printf' call. All the lines start with a
752 tag showing the PID. */
753 extern void _dl_debug_printf (const char *fmt, ...)
754 __attribute__ ((__format__ (__printf__, 1, 2))) attribute_hidden;
756 /* Write message on the debug file descriptor. The parameters are
757 interpreted as for a `printf' call. All the lines buf the first
758 start with a tag showing the PID. */
759 extern void _dl_debug_printf_c (const char *fmt, ...)
760 __attribute__ ((__format__ (__printf__, 1, 2)));
763 /* Write a message on the specified descriptor FD. The parameters are
764 interpreted as for a `printf' call. */
765 extern void _dl_dprintf (int fd, const char *fmt, ...)
766 __attribute__ ((__format__ (__printf__, 2, 3)))
767 attribute_hidden;
769 /* Write a message on the specified descriptor standard output. The
770 parameters are interpreted as for a `printf' call. */
771 #define _dl_printf(fmt, args...) \
772 _dl_dprintf (STDOUT_FILENO, fmt, ##args)
774 /* Write a message on the specified descriptor standard error. The
775 parameters are interpreted as for a `printf' call. */
776 #define _dl_error_printf(fmt, args...) \
777 _dl_dprintf (STDERR_FILENO, fmt, ##args)
779 /* Write a message on the specified descriptor standard error and exit
780 the program. The parameters are interpreted as for a `printf' call. */
781 #define _dl_fatal_printf(fmt, args...) \
782 do \
784 _dl_dprintf (STDERR_FILENO, fmt, ##args); \
785 _exit (127); \
787 while (1)
790 /* This function is called by all the internal dynamic linker functions
791 when they encounter an error. ERRCODE is either an `errno' code or
792 zero; OBJECT is the name of the problematical shared object, or null if
793 it is a general problem; ERRSTRING is a string describing the specific
794 problem. */
795 extern void _dl_signal_error (int errcode, const char *object,
796 const char *occurred, const char *errstring)
797 internal_function __attribute__ ((__noreturn__)) attribute_hidden;
799 /* Like _dl_signal_error, but may return when called in the context of
800 _dl_receive_error. */
801 extern void _dl_signal_cerror (int errcode, const char *object,
802 const char *occation, const char *errstring)
803 internal_function;
805 /* Call OPERATE, receiving errors from `dl_signal_cerror'. Unlike
806 `_dl_catch_error' the operation is resumed after the OPERATE
807 function returns.
808 ARGS is passed as argument to OPERATE. */
809 extern void _dl_receive_error (receiver_fct fct, void (*operate) (void *),
810 void *args)
811 internal_function;
814 /* Open the shared object NAME and map in its segments.
815 LOADER's DT_RPATH is used in searching for NAME.
816 If the object is already opened, returns its existing map. */
817 extern struct link_map *_dl_map_object (struct link_map *loader,
818 const char *name,
819 int type, int trace_mode, int mode,
820 Lmid_t nsid)
821 internal_function attribute_hidden;
823 /* Call _dl_map_object on the dependencies of MAP, and set up
824 MAP->l_searchlist. PRELOADS points to a vector of NPRELOADS previously
825 loaded objects that will be inserted into MAP->l_searchlist after MAP
826 but before its dependencies. */
827 extern void _dl_map_object_deps (struct link_map *map,
828 struct link_map **preloads,
829 unsigned int npreloads, int trace_mode,
830 int open_mode)
831 internal_function attribute_hidden;
833 /* Cache the locations of MAP's hash table. */
834 extern void _dl_setup_hash (struct link_map *map)
835 internal_function attribute_hidden;
838 /* Collect the directories in the search path for LOADER's dependencies.
839 The data structure is defined in <dlfcn.h>. If COUNTING is true,
840 SI->dls_cnt and SI->dls_size are set; if false, those must be as set
841 by a previous call with COUNTING set, and SI must point to SI->dls_size
842 bytes to be used in filling in the result. */
843 extern void _dl_rtld_di_serinfo (struct link_map *loader,
844 Dl_serinfo *si, bool counting)
845 internal_function;
848 /* Search loaded objects' symbol tables for a definition of the symbol
849 referred to by UNDEF. *SYM is the symbol table entry containing the
850 reference; it is replaced with the defining symbol, and the base load
851 address of the defining object is returned. SYMBOL_SCOPE is a
852 null-terminated list of object scopes to search; each object's
853 l_searchlist (i.e. the segment of the dependency tree starting at that
854 object) is searched in turn. REFERENCE_NAME should name the object
855 containing the reference; it is used in error messages.
856 TYPE_CLASS describes the type of symbol we are looking for. */
857 enum
859 /* If necessary add dependency between user and provider object. */
860 DL_LOOKUP_ADD_DEPENDENCY = 1,
861 /* Return most recent version instead of default version for
862 unversioned lookup. */
863 DL_LOOKUP_RETURN_NEWEST = 2,
864 /* Set if dl_lookup* called with GSCOPE lock held. */
865 DL_LOOKUP_GSCOPE_LOCK = 4,
868 /* Lookup versioned symbol. */
869 extern lookup_t _dl_lookup_symbol_x (const char *undef,
870 struct link_map *undef_map,
871 const ElfW(Sym) **sym,
872 struct r_scope_elem *symbol_scope[],
873 const struct r_found_version *version,
874 int type_class, int flags,
875 struct link_map *skip_map)
876 internal_function attribute_hidden;
879 /* Look up symbol NAME in MAP's scope and return its run-time address. */
880 extern ElfW(Addr) _dl_symbol_value (struct link_map *map, const char *name)
881 internal_function;
883 /* Add the new link_map NEW to the end of the namespace list. */
884 extern void _dl_add_to_namespace_list (struct link_map *new, Lmid_t nsid)
885 internal_function attribute_hidden;
887 /* Allocate a `struct link_map' for a new object being loaded. */
888 extern struct link_map *_dl_new_object (char *realname, const char *libname,
889 int type, struct link_map *loader,
890 int mode, Lmid_t nsid)
891 internal_function attribute_hidden;
893 /* Relocate the given object (if it hasn't already been).
894 SCOPE is passed to _dl_lookup_symbol in symbol lookups.
895 If RTLD_LAZY is set in RELOC-MODE, don't relocate its PLT. */
896 extern void _dl_relocate_object (struct link_map *map,
897 struct r_scope_elem *scope[],
898 int reloc_mode, int consider_profiling)
899 attribute_hidden;
901 /* Protect PT_GNU_RELRO area. */
902 extern void _dl_protect_relro (struct link_map *map)
903 internal_function attribute_hidden;
905 /* Call _dl_signal_error with a message about an unhandled reloc type.
906 TYPE is the result of ELFW(R_TYPE) (r_info), i.e. an R_<CPU>_* value.
907 PLT is nonzero if this was a PLT reloc; it just affects the message. */
908 extern void _dl_reloc_bad_type (struct link_map *map,
909 unsigned int type, int plt)
910 internal_function __attribute__ ((__noreturn__));
912 /* Resolve conflicts if prelinking. */
913 extern void _dl_resolve_conflicts (struct link_map *l,
914 ElfW(Rela) *conflict,
915 ElfW(Rela) *conflictend);
917 /* Check the version dependencies of all objects available through
918 MAP. If VERBOSE print some more diagnostics. */
919 extern int _dl_check_all_versions (struct link_map *map, int verbose,
920 int trace_mode)
921 internal_function;
923 /* Check the version dependencies for MAP. If VERBOSE print some more
924 diagnostics. */
925 extern int _dl_check_map_versions (struct link_map *map, int verbose,
926 int trace_mode)
927 internal_function;
929 /* Initialize the object in SCOPE by calling the constructors with
930 ARGC, ARGV, and ENV as the parameters. */
931 extern void _dl_init (struct link_map *main_map, int argc, char **argv,
932 char **env) internal_function attribute_hidden;
934 /* Call the finalizer functions of all shared objects whose
935 initializer functions have completed. */
936 extern void _dl_fini (void) internal_function;
938 /* Sort array MAPS according to dependencies of the contained objects. */
939 extern void _dl_sort_fini (struct link_map **maps, size_t nmaps, char *used,
940 Lmid_t ns)
941 internal_function;
943 /* The dynamic linker calls this function before and having changing
944 any shared object mappings. The `r_state' member of `struct r_debug'
945 says what change is taking place. This function's address is
946 the value of the `r_brk' member. */
947 extern void _dl_debug_state (void);
948 rtld_hidden_proto (_dl_debug_state)
950 /* Initialize `struct r_debug' if it has not already been done. The
951 argument is the run-time load address of the dynamic linker, to be put
952 in the `r_ldbase' member. Returns the address of the structure. */
953 extern struct r_debug *_dl_debug_initialize (ElfW(Addr) ldbase, Lmid_t ns)
954 internal_function;
956 /* Initialize the basic data structure for the search paths. */
957 extern void _dl_init_paths (const char *library_path) internal_function;
959 /* Gather the information needed to install the profiling tables and start
960 the timers. */
961 extern void _dl_start_profile (void) internal_function attribute_hidden;
963 /* The actual functions used to keep book on the calls. */
964 extern void _dl_mcount (ElfW(Addr) frompc, ElfW(Addr) selfpc);
965 extern void _dl_mcount_internal (ElfW(Addr) frompc, ElfW(Addr) selfpc)
966 attribute_hidden;
968 /* This function is simply a wrapper around the _dl_mcount function
969 which does not require a FROMPC parameter since this is the
970 calling function. */
971 extern void _dl_mcount_wrapper (void *selfpc);
973 /* Show the members of the auxiliary array passed up from the kernel. */
974 extern void _dl_show_auxv (void) internal_function;
976 /* Return all environment variables starting with `LD_', one after the
977 other. */
978 extern char *_dl_next_ld_env_entry (char ***position) internal_function;
980 /* Return an array with the names of the important hardware capabilities. */
981 extern const struct r_strlenpair *_dl_important_hwcaps (const char *platform,
982 size_t paltform_len,
983 size_t *sz,
984 size_t *max_capstrlen)
985 internal_function;
987 /* Look up NAME in ld.so.cache and return the file name stored there,
988 or null if none is found. */
989 extern const char *_dl_load_cache_lookup (const char *name)
990 internal_function;
992 /* If the system does not support MAP_COPY we cannot leave the file open
993 all the time since this would create problems when the file is replaced.
994 Therefore we provide this function to close the file and open it again
995 once needed. */
996 extern void _dl_unload_cache (void) attribute_hidden;
998 /* System-dependent function to read a file's whole contents in the
999 most convenient manner available. *SIZEP gets the size of the
1000 file. On error MAP_FAILED is returned. */
1001 extern void *_dl_sysdep_read_whole_file (const char *file, size_t *sizep,
1002 int prot)
1003 internal_function attribute_hidden;
1005 /* System-specific function to do initial startup for the dynamic linker.
1006 After this, file access calls and getenv must work. This is responsible
1007 for setting __libc_enable_secure if we need to be secure (e.g. setuid),
1008 and for setting _dl_argc and _dl_argv, and then calling _dl_main. */
1009 extern ElfW(Addr) _dl_sysdep_start (void **start_argptr,
1010 void (*dl_main) (const ElfW(Phdr) *phdr,
1011 ElfW(Word) phnum,
1012 ElfW(Addr) *user_entry,
1013 ElfW(auxv_t) *auxv))
1014 attribute_hidden;
1016 extern void _dl_sysdep_start_cleanup (void)
1017 internal_function attribute_hidden;
1020 /* Determine next available module ID. */
1021 extern size_t _dl_next_tls_modid (void) internal_function attribute_hidden;
1023 /* Calculate offset of the TLS blocks in the static TLS block. */
1024 extern void _dl_determine_tlsoffset (void) internal_function attribute_hidden;
1026 /* Set up the data structures for TLS, when they were not set up at startup.
1027 Returns nonzero on malloc failure.
1028 This is called from _dl_map_object_from_fd or by libpthread. */
1029 extern int _dl_tls_setup (void) internal_function;
1030 rtld_hidden_proto (_dl_tls_setup)
1032 /* Allocate memory for static TLS block (unless MEM is nonzero) and dtv. */
1033 extern void *_dl_allocate_tls (void *mem) internal_function;
1034 rtld_hidden_proto (_dl_allocate_tls)
1036 /* Get size and alignment requirements of the static TLS block. */
1037 extern void _dl_get_tls_static_info (size_t *sizep, size_t *alignp)
1038 internal_function;
1040 extern void _dl_allocate_static_tls (struct link_map *map)
1041 internal_function attribute_hidden;
1043 /* These are internal entry points to the two halves of _dl_allocate_tls,
1044 only used within rtld.c itself at startup time. */
1045 extern void *_dl_allocate_tls_storage (void)
1046 internal_function attribute_hidden;
1047 extern void *_dl_allocate_tls_init (void *) internal_function;
1048 rtld_hidden_proto (_dl_allocate_tls_init)
1050 /* Deallocate memory allocated with _dl_allocate_tls. */
1051 extern void _dl_deallocate_tls (void *tcb, bool dealloc_tcb) internal_function;
1052 rtld_hidden_proto (_dl_deallocate_tls)
1054 extern void _dl_nothread_init_static_tls (struct link_map *) attribute_hidden;
1056 /* Find origin of the executable. */
1057 extern const char *_dl_get_origin (void) attribute_hidden;
1059 /* Count DSTs. */
1060 extern size_t _dl_dst_count (const char *name, int is_path) attribute_hidden;
1062 /* Substitute DST values. */
1063 extern char *_dl_dst_substitute (struct link_map *l, const char *name,
1064 char *result, int is_path) attribute_hidden;
1066 /* Check validity of the caller. */
1067 extern int _dl_check_caller (const void *caller, enum allowmask mask)
1068 attribute_hidden;
1070 /* Open the shared object NAME, relocate it, and run its initializer if it
1071 hasn't already been run. MODE is as for `dlopen' (see <dlfcn.h>). If
1072 the object is already opened, returns its existing map. */
1073 extern void *_dl_open (const char *name, int mode, const void *caller,
1074 Lmid_t nsid, int argc, char *argv[], char *env[])
1075 attribute_hidden;
1077 /* Free or queue for freeing scope OLD. If other threads might be
1078 in the middle of _dl_fixup, _dl_profile_fixup or dl*sym using the
1079 old scope, OLD can't be freed until no thread is using it. */
1080 extern int _dl_scope_free (void *) attribute_hidden;
1082 /* Add module to slot information data. */
1083 extern void _dl_add_to_slotinfo (struct link_map *l) attribute_hidden;
1085 /* Update slot information data for at least the generation of the
1086 module with the given index. */
1087 extern struct link_map *_dl_update_slotinfo (unsigned long int req_modid);
1089 /* Look up the module's TLS block as for __tls_get_addr,
1090 but never touch anything. Return null if it's not allocated yet. */
1091 extern void *_dl_tls_get_addr_soft (struct link_map *l) attribute_hidden;
1093 extern int _dl_addr_inside_object (struct link_map *l, const ElfW(Addr) addr)
1094 internal_function attribute_hidden;
1096 /* Show show of an object. */
1097 extern void _dl_show_scope (struct link_map *new, int from);
1099 __END_DECLS
1101 #endif /* ldsodefs.h */