mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-05 11:11:04 +00:00
1045 lines
37 KiB
C
1045 lines
37 KiB
C
/* Run-time dynamic linker data structures for loaded ELF shared objects.
|
||
Copyright (C) 1995-2014 Free Software Foundation, Inc.
|
||
This file is part of the GNU C Library.
|
||
|
||
The GNU C Library is free software; you can redistribute it and/or
|
||
modify it under the terms of the GNU Lesser General Public
|
||
License as published by the Free Software Foundation; either
|
||
version 2.1 of the License, or (at your option) any later version.
|
||
|
||
The GNU C Library is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||
Lesser General Public License for more details.
|
||
|
||
You should have received a copy of the GNU Lesser General Public
|
||
License along with the GNU C Library; if not, see
|
||
<http://www.gnu.org/licenses/>. */
|
||
|
||
#ifndef _LDSODEFS_H
|
||
#define _LDSODEFS_H 1
|
||
|
||
#include <features.h>
|
||
|
||
#include <stdbool.h>
|
||
#define __need_size_t
|
||
#define __need_NULL
|
||
#include <stddef.h>
|
||
#include <string.h>
|
||
#include <stdint.h>
|
||
|
||
#include <elf.h>
|
||
#include <dlfcn.h>
|
||
#include <fpu_control.h>
|
||
#include <sys/mman.h>
|
||
#include <link.h>
|
||
#include <dl-lookupcfg.h>
|
||
#include <dl-sysdep.h>
|
||
#include <bits/libc-lock.h>
|
||
#include <hp-timing.h>
|
||
#include <tls.h>
|
||
|
||
__BEGIN_DECLS
|
||
|
||
#define VERSYMIDX(sym) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGIDX (sym))
|
||
#define VALIDX(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM \
|
||
+ DT_EXTRANUM + DT_VALTAGIDX (tag))
|
||
#define ADDRIDX(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM \
|
||
+ DT_EXTRANUM + DT_VALNUM + DT_ADDRTAGIDX (tag))
|
||
|
||
/* We use this macro to refer to ELF types independent of the native wordsize.
|
||
`ElfW(TYPE)' is used in place of `Elf32_TYPE' or `Elf64_TYPE'. */
|
||
#define ELFW(type) _ElfW (ELF, __ELF_NATIVE_CLASS, type)
|
||
|
||
/* All references to the value of l_info[DT_PLTGOT],
|
||
l_info[DT_STRTAB], l_info[DT_SYMTAB], l_info[DT_RELA],
|
||
l_info[DT_REL], l_info[DT_JMPREL], and l_info[VERSYMIDX (DT_VERSYM)]
|
||
have to be accessed via the D_PTR macro. The macro is needed since for
|
||
most architectures the entry is already relocated - but for some not
|
||
and we need to relocate at access time. */
|
||
#ifdef DL_RO_DYN_SECTION
|
||
# define D_PTR(map, i) ((map)->i->d_un.d_ptr + (map)->l_addr)
|
||
#else
|
||
# define D_PTR(map, i) (map)->i->d_un.d_ptr
|
||
#endif
|
||
|
||
/* Result of the lookup functions and how to retrieve the base address. */
|
||
typedef struct link_map *lookup_t;
|
||
#define LOOKUP_VALUE(map) map
|
||
#define LOOKUP_VALUE_ADDRESS(map) ((map) ? (map)->l_addr : 0)
|
||
|
||
/* On some architectures a pointer to a function is not just a pointer
|
||
to the actual code of the function but rather an architecture
|
||
specific descriptor. */
|
||
#ifndef ELF_FUNCTION_PTR_IS_SPECIAL
|
||
# define DL_SYMBOL_ADDRESS(map, ref) \
|
||
(void *) (LOOKUP_VALUE_ADDRESS (map) + ref->st_value)
|
||
# define DL_LOOKUP_ADDRESS(addr) ((ElfW(Addr)) (addr))
|
||
# define DL_CALL_DT_INIT(map, start, argc, argv, env) \
|
||
((init_t) (start)) (argc, argv, env)
|
||
# define DL_CALL_DT_FINI(map, start) ((fini_t) (start)) ()
|
||
#endif
|
||
|
||
/* On some architectures dladdr can't use st_size of all symbols this way. */
|
||
#define DL_ADDR_SYM_MATCH(L, SYM, MATCHSYM, ADDR) \
|
||
((ADDR) >= (L)->l_addr + (SYM)->st_value \
|
||
&& ((((SYM)->st_shndx == SHN_UNDEF || (SYM)->st_size == 0) \
|
||
&& (ADDR) == (L)->l_addr + (SYM)->st_value) \
|
||
|| (ADDR) < (L)->l_addr + (SYM)->st_value + (SYM)->st_size) \
|
||
&& ((MATCHSYM) == NULL || (MATCHSYM)->st_value < (SYM)->st_value))
|
||
|
||
/* Unmap a loaded object, called by _dl_close (). */
|
||
#ifndef DL_UNMAP_IS_SPECIAL
|
||
# define DL_UNMAP(map) _dl_unmap_segments (map)
|
||
#endif
|
||
|
||
/* By default we do not need special support to initialize DSOs loaded
|
||
by statically linked binaries. */
|
||
#ifndef DL_STATIC_INIT
|
||
# define DL_STATIC_INIT(map)
|
||
#endif
|
||
|
||
/* Reloc type classes as returned by elf_machine_type_class().
|
||
ELF_RTYPE_CLASS_PLT means this reloc should not be satisfied by
|
||
some PLT symbol, ELF_RTYPE_CLASS_COPY means this reloc should not be
|
||
satisfied by any symbol in the executable. Some architectures do
|
||
not support copy relocations. In this case we define the macro to
|
||
zero so that the code for handling them gets automatically optimized
|
||
out. */
|
||
#define ELF_RTYPE_CLASS_PLT 1
|
||
#ifndef DL_NO_COPY_RELOCS
|
||
# define ELF_RTYPE_CLASS_COPY 2
|
||
#else
|
||
# define ELF_RTYPE_CLASS_COPY 0
|
||
#endif
|
||
|
||
/* ELF uses the PF_x macros to specify the segment permissions, mmap
|
||
uses PROT_xxx. In most cases the three macros have the values 1, 2,
|
||
and 3 but not in a matching order. The following macros allows
|
||
converting from the PF_x values to PROT_xxx values. */
|
||
#define PF_TO_PROT \
|
||
((PROT_READ << (PF_R * 4)) \
|
||
| (PROT_WRITE << (PF_W * 4)) \
|
||
| (PROT_EXEC << (PF_X * 4)) \
|
||
| ((PROT_READ | PROT_WRITE) << ((PF_R | PF_W) * 4)) \
|
||
| ((PROT_READ | PROT_EXEC) << ((PF_R | PF_X) * 4)) \
|
||
| ((PROT_WRITE | PROT_EXEC) << (PF_W | PF_X) * 4) \
|
||
| ((PROT_READ | PROT_WRITE | PROT_EXEC) << ((PF_R | PF_W | PF_X) * 4)))
|
||
|
||
/* The filename itself, or the main program name, if available. */
|
||
#define DSO_FILENAME(name) ((name)[0] ? (name) \
|
||
: (rtld_progname ?: "<main program>"))
|
||
|
||
#define RTLD_PROGNAME (rtld_progname ?: "<program name unknown>")
|
||
|
||
/* For the version handling we need an array with only names and their
|
||
hash values. */
|
||
struct r_found_version
|
||
{
|
||
const char *name;
|
||
ElfW(Word) hash;
|
||
|
||
int hidden;
|
||
const char *filename;
|
||
};
|
||
|
||
/* We want to cache information about the searches for shared objects. */
|
||
|
||
enum r_dir_status { unknown, nonexisting, existing };
|
||
|
||
struct r_search_path_elem
|
||
{
|
||
/* This link is only used in the `all_dirs' member of `r_search_path'. */
|
||
struct r_search_path_elem *next;
|
||
|
||
/* Strings saying where the definition came from. */
|
||
const char *what;
|
||
const char *where;
|
||
|
||
/* Basename for this search path element. The string must end with
|
||
a slash character. */
|
||
const char *dirname;
|
||
size_t dirnamelen;
|
||
|
||
enum r_dir_status status[0];
|
||
};
|
||
|
||
struct r_strlenpair
|
||
{
|
||
const char *str;
|
||
size_t len;
|
||
};
|
||
|
||
|
||
/* A data structure for a simple single linked list of strings. */
|
||
struct libname_list
|
||
{
|
||
const char *name; /* Name requested (before search). */
|
||
struct libname_list *next; /* Link to next name for this object. */
|
||
int dont_free; /* Flag whether this element should be freed
|
||
if the object is not entirely unloaded. */
|
||
};
|
||
|
||
|
||
/* Bit masks for the objects which valid callers can come from to
|
||
functions with restricted interface. */
|
||
enum allowmask
|
||
{
|
||
allow_libc = 1,
|
||
allow_libdl = 2,
|
||
allow_libpthread = 4,
|
||
allow_ldso = 8
|
||
};
|
||
|
||
|
||
struct audit_ifaces
|
||
{
|
||
void (*activity) (uintptr_t *, unsigned int);
|
||
char *(*objsearch) (const char *, uintptr_t *, unsigned int);
|
||
unsigned int (*objopen) (struct link_map *, Lmid_t, uintptr_t *);
|
||
void (*preinit) (uintptr_t *);
|
||
union
|
||
{
|
||
uintptr_t (*symbind32) (Elf32_Sym *, unsigned int, uintptr_t *,
|
||
uintptr_t *, unsigned int *, const char *);
|
||
uintptr_t (*symbind64) (Elf64_Sym *, unsigned int, uintptr_t *,
|
||
uintptr_t *, unsigned int *, const char *);
|
||
};
|
||
union
|
||
{
|
||
#ifdef ARCH_PLTENTER_MEMBERS
|
||
ARCH_PLTENTER_MEMBERS;
|
||
#endif
|
||
};
|
||
union
|
||
{
|
||
#ifdef ARCH_PLTEXIT_MEMBERS
|
||
ARCH_PLTEXIT_MEMBERS;
|
||
#endif
|
||
};
|
||
unsigned int (*objclose) (uintptr_t *);
|
||
|
||
struct audit_ifaces *next;
|
||
};
|
||
|
||
|
||
/* Test whether given NAME matches any of the names of the given object. */
|
||
extern int _dl_name_match_p (const char *__name, const struct link_map *__map)
|
||
internal_function;
|
||
|
||
/* Compute next higher prime number. */
|
||
extern unsigned long int _dl_higher_prime_number (unsigned long int n)
|
||
internal_function;
|
||
|
||
/* Function used as argument for `_dl_receive_error' function. The
|
||
arguments are the error code, error string, and the objname the
|
||
error occurred in. */
|
||
typedef void (*receiver_fct) (int, const char *, const char *);
|
||
|
||
/* Internal functions of the run-time dynamic linker.
|
||
These can be accessed if you link again the dynamic linker
|
||
as a shared library, as in `-lld' or `/lib/ld.so' explicitly;
|
||
but are not normally of interest to user programs.
|
||
|
||
The `-ldl' library functions in <dlfcn.h> provide a simple
|
||
user interface to run-time dynamic linking. */
|
||
|
||
|
||
#ifndef SHARED
|
||
# define EXTERN extern
|
||
# define GL(name) _##name
|
||
#else
|
||
# define EXTERN
|
||
# ifdef IS_IN_rtld
|
||
# define GL(name) _rtld_local._##name
|
||
# else
|
||
# define GL(name) _rtld_global._##name
|
||
# endif
|
||
struct rtld_global
|
||
{
|
||
#endif
|
||
/* Don't change the order of the following elements. 'dl_loaded'
|
||
must remain the first element. Forever. */
|
||
|
||
/* Non-shared code has no support for multiple namespaces. */
|
||
#ifdef SHARED
|
||
# define DL_NNS 16
|
||
#else
|
||
# define DL_NNS 1
|
||
#endif
|
||
EXTERN struct link_namespaces
|
||
{
|
||
/* A pointer to the map for the main map. */
|
||
struct link_map *_ns_loaded;
|
||
/* Number of object in the _dl_loaded list. */
|
||
unsigned int _ns_nloaded;
|
||
/* Direct pointer to the searchlist of the main object. */
|
||
struct r_scope_elem *_ns_main_searchlist;
|
||
/* This is zero at program start to signal that the global scope map is
|
||
allocated by rtld. Later it keeps the size of the map. It might be
|
||
reset if in _dl_close if the last global object is removed. */
|
||
size_t _ns_global_scope_alloc;
|
||
/* Search table for unique objects. */
|
||
struct unique_sym_table
|
||
{
|
||
__rtld_lock_define_recursive (, lock)
|
||
struct unique_sym
|
||
{
|
||
uint32_t hashval;
|
||
const char *name;
|
||
const ElfW(Sym) *sym;
|
||
const struct link_map *map;
|
||
} *entries;
|
||
size_t size;
|
||
size_t n_elements;
|
||
void (*free) (void *);
|
||
} _ns_unique_sym_table;
|
||
/* Keep track of changes to each namespace' list. */
|
||
struct r_debug _ns_debug;
|
||
} _dl_ns[DL_NNS];
|
||
/* One higher than index of last used namespace. */
|
||
EXTERN size_t _dl_nns;
|
||
|
||
/* During the program run we must not modify the global data of
|
||
loaded shared object simultanously in two threads. Therefore we
|
||
protect `_dl_open' and `_dl_close' in dl-close.c.
|
||
|
||
This must be a recursive lock since the initializer function of
|
||
the loaded object might as well require a call to this function.
|
||
At this time it is not anymore a problem to modify the tables. */
|
||
__rtld_lock_define_recursive (EXTERN, _dl_load_lock)
|
||
/* This lock is used to keep __dl_iterate_phdr from inspecting the
|
||
list of loaded objects while an object is added to or removed
|
||
from that list. */
|
||
__rtld_lock_define_recursive (EXTERN, _dl_load_write_lock)
|
||
|
||
/* Incremented whenever something may have been added to dl_loaded. */
|
||
EXTERN unsigned long long _dl_load_adds;
|
||
|
||
/* The object to be initialized first. */
|
||
EXTERN struct link_map *_dl_initfirst;
|
||
|
||
#if HP_SMALL_TIMING_AVAIL
|
||
/* Start time on CPU clock. */
|
||
EXTERN hp_timing_t _dl_cpuclock_offset;
|
||
#endif
|
||
|
||
/* Map of shared object to be profiled. */
|
||
EXTERN struct link_map *_dl_profile_map;
|
||
|
||
/* Counters for the number of relocations performed. */
|
||
EXTERN unsigned long int _dl_num_relocations;
|
||
EXTERN unsigned long int _dl_num_cache_relocations;
|
||
|
||
/* List of search directories. */
|
||
EXTERN struct r_search_path_elem *_dl_all_dirs;
|
||
|
||
#ifdef _LIBC_REENTRANT
|
||
EXTERN void **(*_dl_error_catch_tsd) (void) __attribute__ ((const));
|
||
#endif
|
||
|
||
/* Structure describing the dynamic linker itself. We need to
|
||
reserve memory for the data the audit libraries need. */
|
||
EXTERN struct link_map _dl_rtld_map;
|
||
#ifdef SHARED
|
||
struct auditstate audit_data[DL_NNS];
|
||
#endif
|
||
|
||
#if defined SHARED && defined _LIBC_REENTRANT \
|
||
&& defined __rtld_lock_default_lock_recursive
|
||
EXTERN void (*_dl_rtld_lock_recursive) (void *);
|
||
EXTERN void (*_dl_rtld_unlock_recursive) (void *);
|
||
#endif
|
||
|
||
/* If loading a shared object requires that we make the stack executable
|
||
when it was not, we do it by calling this function.
|
||
It returns an errno code or zero on success. */
|
||
EXTERN int (*_dl_make_stack_executable_hook) (void **) internal_function;
|
||
|
||
/* Prevailing state of the stack, PF_X indicating it's executable. */
|
||
EXTERN ElfW(Word) _dl_stack_flags;
|
||
|
||
/* Flag signalling whether there are gaps in the module ID allocation. */
|
||
EXTERN bool _dl_tls_dtv_gaps;
|
||
/* Highest dtv index currently needed. */
|
||
EXTERN size_t _dl_tls_max_dtv_idx;
|
||
/* Information about the dtv slots. */
|
||
EXTERN struct dtv_slotinfo_list
|
||
{
|
||
size_t len;
|
||
struct dtv_slotinfo_list *next;
|
||
struct dtv_slotinfo
|
||
{
|
||
size_t gen;
|
||
struct link_map *map;
|
||
} slotinfo[0];
|
||
} *_dl_tls_dtv_slotinfo_list;
|
||
/* Number of modules in the static TLS block. */
|
||
EXTERN size_t _dl_tls_static_nelem;
|
||
/* Size of the static TLS block. */
|
||
EXTERN size_t _dl_tls_static_size;
|
||
/* Size actually allocated in the static TLS block. */
|
||
EXTERN size_t _dl_tls_static_used;
|
||
/* Alignment requirement of the static TLS block. */
|
||
EXTERN size_t _dl_tls_static_align;
|
||
|
||
/* Number of additional entries in the slotinfo array of each slotinfo
|
||
list element. A large number makes it almost certain take we never
|
||
have to iterate beyond the first element in the slotinfo list. */
|
||
#define TLS_SLOTINFO_SURPLUS (62)
|
||
|
||
/* Number of additional slots in the dtv allocated. */
|
||
#define DTV_SURPLUS (14)
|
||
|
||
/* Initial dtv of the main thread, not allocated with normal malloc. */
|
||
EXTERN void *_dl_initial_dtv;
|
||
/* Generation counter for the dtv. */
|
||
EXTERN size_t _dl_tls_generation;
|
||
|
||
EXTERN void (*_dl_init_static_tls) (struct link_map *);
|
||
|
||
EXTERN void (*_dl_wait_lookup_done) (void);
|
||
|
||
/* Scopes to free after next THREAD_GSCOPE_WAIT (). */
|
||
EXTERN struct dl_scope_free_list
|
||
{
|
||
size_t count;
|
||
void *list[50];
|
||
} *_dl_scope_free_list;
|
||
#ifdef SHARED
|
||
};
|
||
# define __rtld_global_attribute__
|
||
# ifdef IS_IN_rtld
|
||
# ifdef HAVE_SDATA_SECTION
|
||
# define __rtld_local_attribute__ \
|
||
__attribute__ ((visibility ("hidden"), section (".sdata")))
|
||
# undef __rtld_global_attribute__
|
||
# define __rtld_global_attribute__ __attribute__ ((section (".sdata")))
|
||
# else
|
||
# define __rtld_local_attribute__ __attribute__ ((visibility ("hidden")))
|
||
# endif
|
||
extern struct rtld_global _rtld_local __rtld_local_attribute__;
|
||
# undef __rtld_local_attribute__
|
||
# endif
|
||
extern struct rtld_global _rtld_global __rtld_global_attribute__;
|
||
# undef __rtld_global_attribute__
|
||
#endif
|
||
|
||
#ifndef SHARED
|
||
# define GLRO(name) _##name
|
||
#else
|
||
# ifdef IS_IN_rtld
|
||
# define GLRO(name) _rtld_local_ro._##name
|
||
# else
|
||
# define GLRO(name) _rtld_global_ro._##name
|
||
# endif
|
||
struct rtld_global_ro
|
||
{
|
||
#endif
|
||
|
||
/* If nonzero the appropriate debug information is printed. */
|
||
EXTERN int _dl_debug_mask;
|
||
#define DL_DEBUG_LIBS (1 << 0)
|
||
#define DL_DEBUG_IMPCALLS (1 << 1)
|
||
#define DL_DEBUG_BINDINGS (1 << 2)
|
||
#define DL_DEBUG_SYMBOLS (1 << 3)
|
||
#define DL_DEBUG_VERSIONS (1 << 4)
|
||
#define DL_DEBUG_RELOC (1 << 5)
|
||
#define DL_DEBUG_FILES (1 << 6)
|
||
#define DL_DEBUG_STATISTICS (1 << 7)
|
||
#define DL_DEBUG_UNUSED (1 << 8)
|
||
#define DL_DEBUG_SCOPES (1 << 9)
|
||
/* These two are used only internally. */
|
||
#define DL_DEBUG_HELP (1 << 10)
|
||
#define DL_DEBUG_PRELINK (1 << 11)
|
||
|
||
/* OS version. */
|
||
EXTERN unsigned int _dl_osversion;
|
||
/* Platform name. */
|
||
EXTERN const char *_dl_platform;
|
||
EXTERN size_t _dl_platformlen;
|
||
|
||
/* Cached value of `getpagesize ()'. */
|
||
EXTERN size_t _dl_pagesize;
|
||
|
||
/* Do we read from ld.so.cache? */
|
||
EXTERN int _dl_inhibit_cache;
|
||
|
||
/* Copy of the content of `_dl_main_searchlist' at startup time. */
|
||
EXTERN struct r_scope_elem _dl_initial_searchlist;
|
||
|
||
/* CLK_TCK as reported by the kernel. */
|
||
EXTERN int _dl_clktck;
|
||
|
||
/* If nonzero print warnings messages. */
|
||
EXTERN int _dl_verbose;
|
||
|
||
/* File descriptor to write debug messages to. */
|
||
EXTERN int _dl_debug_fd;
|
||
|
||
/* Do we do lazy relocations? */
|
||
EXTERN int _dl_lazy;
|
||
|
||
/* Nonzero if runtime lookups should not update the .got/.plt. */
|
||
EXTERN int _dl_bind_not;
|
||
|
||
/* Nonzero if references should be treated as weak during runtime
|
||
linking. */
|
||
EXTERN int _dl_dynamic_weak;
|
||
|
||
/* Default floating-point control word. */
|
||
EXTERN fpu_control_t _dl_fpu_control;
|
||
|
||
/* Expected cache ID. */
|
||
EXTERN int _dl_correct_cache_id;
|
||
|
||
/* Mask for hardware capabilities that are available. */
|
||
EXTERN uint64_t _dl_hwcap;
|
||
|
||
/* Mask for important hardware capabilities we honour. */
|
||
EXTERN uint64_t _dl_hwcap_mask;
|
||
|
||
/* Pointer to the auxv list supplied to the program at startup. */
|
||
EXTERN ElfW(auxv_t) *_dl_auxv;
|
||
|
||
/* Get architecture specific definitions. */
|
||
#define PROCINFO_DECL
|
||
#ifndef PROCINFO_CLASS
|
||
# define PROCINFO_CLASS EXTERN
|
||
#endif
|
||
#include <dl-procinfo.c>
|
||
|
||
/* Names of shared object for which the RPATH should be ignored. */
|
||
EXTERN const char *_dl_inhibit_rpath;
|
||
|
||
/* Location of the binary. */
|
||
EXTERN const char *_dl_origin_path;
|
||
|
||
/* -1 if the dynamic linker should honor library load bias,
|
||
0 if not, -2 use the default (honor biases for normal
|
||
binaries, don't honor for PIEs). */
|
||
EXTERN ElfW(Addr) _dl_use_load_bias;
|
||
|
||
/* Name of the shared object to be profiled (if any). */
|
||
EXTERN const char *_dl_profile;
|
||
/* Filename of the output file. */
|
||
EXTERN const char *_dl_profile_output;
|
||
/* Name of the object we want to trace the prelinking. */
|
||
EXTERN const char *_dl_trace_prelink;
|
||
/* Map of shared object to be prelink traced. */
|
||
EXTERN struct link_map *_dl_trace_prelink_map;
|
||
|
||
/* All search directories defined at startup. */
|
||
EXTERN struct r_search_path_elem *_dl_init_all_dirs;
|
||
|
||
#ifdef NEED_DL_SYSINFO
|
||
/* Syscall handling improvements. This is very specific to x86. */
|
||
EXTERN uintptr_t _dl_sysinfo;
|
||
#endif
|
||
|
||
#ifdef NEED_DL_SYSINFO_DSO
|
||
/* The vsyscall page is a virtual DSO pre-mapped by the kernel.
|
||
This points to its ELF header. */
|
||
EXTERN const ElfW(Ehdr) *_dl_sysinfo_dso;
|
||
|
||
/* At startup time we set up the normal DSO data structure for it,
|
||
and this points to it. */
|
||
EXTERN struct link_map *_dl_sysinfo_map;
|
||
#endif
|
||
|
||
/* Mask for more hardware capabilities that are available on some
|
||
platforms. */
|
||
EXTERN uint64_t _dl_hwcap2;
|
||
|
||
#ifdef SHARED
|
||
/* We add a function table to _rtld_global which is then used to
|
||
call the function instead of going through the PLT. The result
|
||
is that we can avoid exporting the functions and we do not jump
|
||
PLT relocations in libc.so. */
|
||
void (*_dl_debug_printf) (const char *, ...)
|
||
__attribute__ ((__format__ (__printf__, 1, 2)));
|
||
int (internal_function *_dl_catch_error) (const char **, const char **,
|
||
bool *, void (*) (void *), void *);
|
||
void (internal_function *_dl_signal_error) (int, const char *, const char *,
|
||
const char *);
|
||
void (*_dl_mcount) (ElfW(Addr) frompc, ElfW(Addr) selfpc);
|
||
lookup_t (internal_function *_dl_lookup_symbol_x) (const char *,
|
||
struct link_map *,
|
||
const ElfW(Sym) **,
|
||
struct r_scope_elem *[],
|
||
const struct r_found_version *,
|
||
int, int,
|
||
struct link_map *);
|
||
int (*_dl_check_caller) (const void *, enum allowmask);
|
||
void *(*_dl_open) (const char *file, int mode, const void *caller_dlopen,
|
||
Lmid_t nsid, int argc, char *argv[], char *env[]);
|
||
void (*_dl_close) (void *map);
|
||
void *(*_dl_tls_get_addr_soft) (struct link_map *);
|
||
#ifdef HAVE_DL_DISCOVER_OSVERSION
|
||
int (*_dl_discover_osversion) (void);
|
||
#endif
|
||
|
||
/* List of auditing interfaces. */
|
||
struct audit_ifaces *_dl_audit;
|
||
unsigned int _dl_naudit;
|
||
|
||
/* 0 if internal pointer values should not be guarded, 1 if they should. */
|
||
EXTERN int _dl_pointer_guard;
|
||
};
|
||
# define __rtld_global_attribute__
|
||
# ifdef IS_IN_rtld
|
||
# define __rtld_local_attribute__ __attribute__ ((visibility ("hidden")))
|
||
extern struct rtld_global_ro _rtld_local_ro
|
||
attribute_relro __rtld_local_attribute__;
|
||
extern struct rtld_global_ro _rtld_global_ro
|
||
attribute_relro __rtld_global_attribute__;
|
||
# undef __rtld_local_attribute__
|
||
# else
|
||
/* We cheat a bit here. We declare the variable as as const even
|
||
though it is at startup. */
|
||
extern const struct rtld_global_ro _rtld_global_ro
|
||
attribute_relro __rtld_global_attribute__;
|
||
# endif
|
||
# undef __rtld_global_attribute__
|
||
#endif
|
||
#undef EXTERN
|
||
|
||
#ifndef SHARED
|
||
/* dl-support.c defines these and initializes them early on. */
|
||
extern const ElfW(Phdr) *_dl_phdr;
|
||
extern size_t _dl_phnum;
|
||
#endif
|
||
|
||
#ifdef IS_IN_rtld
|
||
/* This is the initial value of GL(dl_error_catch_tsd).
|
||
A non-TLS libpthread will change it. */
|
||
extern void **_dl_initial_error_catch_tsd (void) __attribute__ ((const))
|
||
attribute_hidden;
|
||
#endif
|
||
|
||
/* This is the initial value of GL(dl_make_stack_executable_hook).
|
||
A threads library can change it. */
|
||
extern int _dl_make_stack_executable (void **stack_endp) internal_function;
|
||
rtld_hidden_proto (_dl_make_stack_executable)
|
||
|
||
/* Variable pointing to the end of the stack (or close to it). This value
|
||
must be constant over the runtime of the application. Some programs
|
||
might use the variable which results in copy relocations on some
|
||
platforms. But this does not matter, ld.so can always use the local
|
||
copy. */
|
||
extern void *__libc_stack_end
|
||
#ifndef LIBC_STACK_END_NOT_RELRO
|
||
attribute_relro
|
||
#endif
|
||
;
|
||
rtld_hidden_proto (__libc_stack_end)
|
||
|
||
/* Parameters passed to the dynamic linker. */
|
||
extern int _dl_argc attribute_hidden attribute_relro;
|
||
extern char **_dl_argv
|
||
#ifndef DL_ARGV_NOT_RELRO
|
||
attribute_relro
|
||
#endif
|
||
;
|
||
#ifdef IS_IN_rtld
|
||
extern unsigned int _dl_skip_args attribute_hidden
|
||
# ifndef DL_ARGV_NOT_RELRO
|
||
attribute_relro
|
||
# endif
|
||
;
|
||
extern unsigned int _dl_skip_args_internal attribute_hidden
|
||
# ifndef DL_ARGV_NOT_RELRO
|
||
attribute_relro
|
||
# endif
|
||
;
|
||
extern char **_dl_argv_internal attribute_hidden
|
||
# ifndef DL_ARGV_NOT_RELRO
|
||
attribute_relro
|
||
# endif
|
||
;
|
||
# define rtld_progname (INTUSE(_dl_argv)[0])
|
||
#else
|
||
# define rtld_progname _dl_argv[0]
|
||
#endif
|
||
|
||
/* Flag set at startup and cleared when the last initializer has run. */
|
||
extern int _dl_starting_up;
|
||
weak_extern (_dl_starting_up)
|
||
#ifdef IS_IN_rtld
|
||
extern int _dl_starting_up_internal attribute_hidden;
|
||
#endif
|
||
|
||
/* Random data provided by the kernel. */
|
||
extern void *_dl_random attribute_hidden attribute_relro;
|
||
|
||
/* OS-dependent function to open the zero-fill device. */
|
||
extern int _dl_sysdep_open_zero_fill (void); /* dl-sysdep.c */
|
||
|
||
|
||
/* Write message on the debug file descriptor. The parameters are
|
||
interpreted as for a `printf' call. All the lines start with a
|
||
tag showing the PID. */
|
||
extern void _dl_debug_printf (const char *fmt, ...)
|
||
__attribute__ ((__format__ (__printf__, 1, 2))) attribute_hidden;
|
||
|
||
/* Write message on the debug file descriptor. The parameters are
|
||
interpreted as for a `printf' call. All the lines buf the first
|
||
start with a tag showing the PID. */
|
||
extern void _dl_debug_printf_c (const char *fmt, ...)
|
||
__attribute__ ((__format__ (__printf__, 1, 2)));
|
||
|
||
|
||
/* Write a message on the specified descriptor FD. The parameters are
|
||
interpreted as for a `printf' call. */
|
||
extern void _dl_dprintf (int fd, const char *fmt, ...)
|
||
__attribute__ ((__format__ (__printf__, 2, 3)))
|
||
attribute_hidden;
|
||
|
||
/* Write a message on the specified descriptor standard output. The
|
||
parameters are interpreted as for a `printf' call. */
|
||
#define _dl_printf(fmt, args...) \
|
||
_dl_dprintf (STDOUT_FILENO, fmt, ##args)
|
||
|
||
/* Write a message on the specified descriptor standard error. The
|
||
parameters are interpreted as for a `printf' call. */
|
||
#define _dl_error_printf(fmt, args...) \
|
||
_dl_dprintf (STDERR_FILENO, fmt, ##args)
|
||
|
||
/* Write a message on the specified descriptor standard error and exit
|
||
the program. The parameters are interpreted as for a `printf' call. */
|
||
#define _dl_fatal_printf(fmt, args...) \
|
||
do \
|
||
{ \
|
||
_dl_dprintf (STDERR_FILENO, fmt, ##args); \
|
||
_exit (127); \
|
||
} \
|
||
while (1)
|
||
|
||
|
||
/* This function is called by all the internal dynamic linker functions
|
||
when they encounter an error. ERRCODE is either an `errno' code or
|
||
zero; OBJECT is the name of the problematical shared object, or null if
|
||
it is a general problem; ERRSTRING is a string describing the specific
|
||
problem. */
|
||
extern void _dl_signal_error (int errcode, const char *object,
|
||
const char *occurred, const char *errstring)
|
||
internal_function __attribute__ ((__noreturn__)) attribute_hidden;
|
||
|
||
/* Like _dl_signal_error, but may return when called in the context of
|
||
_dl_receive_error. */
|
||
extern void _dl_signal_cerror (int errcode, const char *object,
|
||
const char *occation, const char *errstring)
|
||
internal_function;
|
||
|
||
/* Call OPERATE, receiving errors from `dl_signal_cerror'. Unlike
|
||
`_dl_catch_error' the operation is resumed after the OPERATE
|
||
function returns.
|
||
ARGS is passed as argument to OPERATE. */
|
||
extern void _dl_receive_error (receiver_fct fct, void (*operate) (void *),
|
||
void *args)
|
||
internal_function;
|
||
|
||
|
||
/* Open the shared object NAME and map in its segments.
|
||
LOADER's DT_RPATH is used in searching for NAME.
|
||
If the object is already opened, returns its existing map. */
|
||
extern struct link_map *_dl_map_object (struct link_map *loader,
|
||
const char *name,
|
||
int type, int trace_mode, int mode,
|
||
Lmid_t nsid)
|
||
internal_function attribute_hidden;
|
||
|
||
/* Call _dl_map_object on the dependencies of MAP, and set up
|
||
MAP->l_searchlist. PRELOADS points to a vector of NPRELOADS previously
|
||
loaded objects that will be inserted into MAP->l_searchlist after MAP
|
||
but before its dependencies. */
|
||
extern void _dl_map_object_deps (struct link_map *map,
|
||
struct link_map **preloads,
|
||
unsigned int npreloads, int trace_mode,
|
||
int open_mode)
|
||
internal_function attribute_hidden;
|
||
|
||
/* Cache the locations of MAP's hash table. */
|
||
extern void _dl_setup_hash (struct link_map *map)
|
||
internal_function attribute_hidden;
|
||
|
||
|
||
/* Collect the directories in the search path for LOADER's dependencies.
|
||
The data structure is defined in <dlfcn.h>. If COUNTING is true,
|
||
SI->dls_cnt and SI->dls_size are set; if false, those must be as set
|
||
by a previous call with COUNTING set, and SI must point to SI->dls_size
|
||
bytes to be used in filling in the result. */
|
||
extern void _dl_rtld_di_serinfo (struct link_map *loader,
|
||
Dl_serinfo *si, bool counting)
|
||
internal_function;
|
||
|
||
|
||
/* Search loaded objects' symbol tables for a definition of the symbol
|
||
referred to by UNDEF. *SYM is the symbol table entry containing the
|
||
reference; it is replaced with the defining symbol, and the base load
|
||
address of the defining object is returned. SYMBOL_SCOPE is a
|
||
null-terminated list of object scopes to search; each object's
|
||
l_searchlist (i.e. the segment of the dependency tree starting at that
|
||
object) is searched in turn. REFERENCE_NAME should name the object
|
||
containing the reference; it is used in error messages.
|
||
TYPE_CLASS describes the type of symbol we are looking for. */
|
||
enum
|
||
{
|
||
/* If necessary add dependency between user and provider object. */
|
||
DL_LOOKUP_ADD_DEPENDENCY = 1,
|
||
/* Return most recent version instead of default version for
|
||
unversioned lookup. */
|
||
DL_LOOKUP_RETURN_NEWEST = 2,
|
||
/* Set if dl_lookup* called with GSCOPE lock held. */
|
||
DL_LOOKUP_GSCOPE_LOCK = 4,
|
||
};
|
||
|
||
/* Lookup versioned symbol. */
|
||
extern lookup_t _dl_lookup_symbol_x (const char *undef,
|
||
struct link_map *undef_map,
|
||
const ElfW(Sym) **sym,
|
||
struct r_scope_elem *symbol_scope[],
|
||
const struct r_found_version *version,
|
||
int type_class, int flags,
|
||
struct link_map *skip_map)
|
||
internal_function attribute_hidden;
|
||
|
||
|
||
/* Look up symbol NAME in MAP's scope and return its run-time address. */
|
||
extern ElfW(Addr) _dl_symbol_value (struct link_map *map, const char *name)
|
||
internal_function;
|
||
|
||
/* Add the new link_map NEW to the end of the namespace list. */
|
||
extern void _dl_add_to_namespace_list (struct link_map *new, Lmid_t nsid)
|
||
internal_function attribute_hidden;
|
||
|
||
/* Allocate a `struct link_map' for a new object being loaded. */
|
||
extern struct link_map *_dl_new_object (char *realname, const char *libname,
|
||
int type, struct link_map *loader,
|
||
int mode, Lmid_t nsid)
|
||
internal_function attribute_hidden;
|
||
|
||
/* Relocate the given object (if it hasn't already been).
|
||
SCOPE is passed to _dl_lookup_symbol in symbol lookups.
|
||
If RTLD_LAZY is set in RELOC-MODE, don't relocate its PLT. */
|
||
extern void _dl_relocate_object (struct link_map *map,
|
||
struct r_scope_elem *scope[],
|
||
int reloc_mode, int consider_profiling)
|
||
attribute_hidden;
|
||
|
||
/* Protect PT_GNU_RELRO area. */
|
||
extern void _dl_protect_relro (struct link_map *map)
|
||
internal_function attribute_hidden;
|
||
|
||
/* Call _dl_signal_error with a message about an unhandled reloc type.
|
||
TYPE is the result of ELFW(R_TYPE) (r_info), i.e. an R_<CPU>_* value.
|
||
PLT is nonzero if this was a PLT reloc; it just affects the message. */
|
||
extern void _dl_reloc_bad_type (struct link_map *map,
|
||
unsigned int type, int plt)
|
||
internal_function __attribute__ ((__noreturn__));
|
||
|
||
/* Resolve conflicts if prelinking. */
|
||
extern void _dl_resolve_conflicts (struct link_map *l,
|
||
ElfW(Rela) *conflict,
|
||
ElfW(Rela) *conflictend);
|
||
|
||
/* Check the version dependencies of all objects available through
|
||
MAP. If VERBOSE print some more diagnostics. */
|
||
extern int _dl_check_all_versions (struct link_map *map, int verbose,
|
||
int trace_mode)
|
||
internal_function;
|
||
|
||
/* Check the version dependencies for MAP. If VERBOSE print some more
|
||
diagnostics. */
|
||
extern int _dl_check_map_versions (struct link_map *map, int verbose,
|
||
int trace_mode)
|
||
internal_function;
|
||
|
||
/* Initialize the object in SCOPE by calling the constructors with
|
||
ARGC, ARGV, and ENV as the parameters. */
|
||
extern void _dl_init (struct link_map *main_map, int argc, char **argv,
|
||
char **env) internal_function attribute_hidden;
|
||
|
||
/* Call the finalizer functions of all shared objects whose
|
||
initializer functions have completed. */
|
||
extern void _dl_fini (void) internal_function;
|
||
|
||
/* Sort array MAPS according to dependencies of the contained objects. */
|
||
extern void _dl_sort_fini (struct link_map **maps, size_t nmaps, char *used,
|
||
Lmid_t ns)
|
||
internal_function;
|
||
|
||
/* The dynamic linker calls this function before and having changing
|
||
any shared object mappings. The `r_state' member of `struct r_debug'
|
||
says what change is taking place. This function's address is
|
||
the value of the `r_brk' member. */
|
||
extern void _dl_debug_state (void);
|
||
rtld_hidden_proto (_dl_debug_state)
|
||
|
||
/* Initialize `struct r_debug' if it has not already been done. The
|
||
argument is the run-time load address of the dynamic linker, to be put
|
||
in the `r_ldbase' member. Returns the address of the structure. */
|
||
extern struct r_debug *_dl_debug_initialize (ElfW(Addr) ldbase, Lmid_t ns)
|
||
internal_function;
|
||
|
||
/* Initialize the basic data structure for the search paths. */
|
||
extern void _dl_init_paths (const char *library_path) internal_function;
|
||
|
||
/* Gather the information needed to install the profiling tables and start
|
||
the timers. */
|
||
extern void _dl_start_profile (void) internal_function attribute_hidden;
|
||
|
||
/* The actual functions used to keep book on the calls. */
|
||
extern void _dl_mcount (ElfW(Addr) frompc, ElfW(Addr) selfpc);
|
||
extern void _dl_mcount_internal (ElfW(Addr) frompc, ElfW(Addr) selfpc)
|
||
attribute_hidden;
|
||
|
||
/* This function is simply a wrapper around the _dl_mcount function
|
||
which does not require a FROMPC parameter since this is the
|
||
calling function. */
|
||
extern void _dl_mcount_wrapper (void *selfpc);
|
||
|
||
/* Show the members of the auxiliary array passed up from the kernel. */
|
||
extern void _dl_show_auxv (void) internal_function;
|
||
|
||
/* Return all environment variables starting with `LD_', one after the
|
||
other. */
|
||
extern char *_dl_next_ld_env_entry (char ***position) internal_function;
|
||
|
||
/* Return an array with the names of the important hardware capabilities. */
|
||
extern const struct r_strlenpair *_dl_important_hwcaps (const char *platform,
|
||
size_t paltform_len,
|
||
size_t *sz,
|
||
size_t *max_capstrlen)
|
||
internal_function;
|
||
|
||
/* Look up NAME in ld.so.cache and return the file name stored there,
|
||
or null if none is found. */
|
||
extern const char *_dl_load_cache_lookup (const char *name)
|
||
internal_function;
|
||
|
||
/* If the system does not support MAP_COPY we cannot leave the file open
|
||
all the time since this would create problems when the file is replaced.
|
||
Therefore we provide this function to close the file and open it again
|
||
once needed. */
|
||
extern void _dl_unload_cache (void) attribute_hidden;
|
||
|
||
/* System-dependent function to read a file's whole contents in the
|
||
most convenient manner available. *SIZEP gets the size of the
|
||
file. On error MAP_FAILED is returned. */
|
||
extern void *_dl_sysdep_read_whole_file (const char *file, size_t *sizep,
|
||
int prot)
|
||
internal_function attribute_hidden;
|
||
|
||
/* System-specific function to do initial startup for the dynamic linker.
|
||
After this, file access calls and getenv must work. This is responsible
|
||
for setting __libc_enable_secure if we need to be secure (e.g. setuid),
|
||
and for setting _dl_argc and _dl_argv, and then calling _dl_main. */
|
||
extern ElfW(Addr) _dl_sysdep_start (void **start_argptr,
|
||
void (*dl_main) (const ElfW(Phdr) *phdr,
|
||
ElfW(Word) phnum,
|
||
ElfW(Addr) *user_entry,
|
||
ElfW(auxv_t) *auxv))
|
||
attribute_hidden;
|
||
|
||
extern void _dl_sysdep_start_cleanup (void)
|
||
internal_function attribute_hidden;
|
||
|
||
|
||
/* Determine next available module ID. */
|
||
extern size_t _dl_next_tls_modid (void) internal_function attribute_hidden;
|
||
|
||
/* Count the modules with TLS segments. */
|
||
extern size_t _dl_count_modids (void) internal_function attribute_hidden;
|
||
|
||
/* Calculate offset of the TLS blocks in the static TLS block. */
|
||
extern void _dl_determine_tlsoffset (void) internal_function attribute_hidden;
|
||
|
||
/* Set up the data structures for TLS, when they were not set up at startup.
|
||
Returns nonzero on malloc failure.
|
||
This is called from _dl_map_object_from_fd or by libpthread. */
|
||
extern int _dl_tls_setup (void) internal_function;
|
||
rtld_hidden_proto (_dl_tls_setup)
|
||
|
||
/* Allocate memory for static TLS block (unless MEM is nonzero) and dtv. */
|
||
extern void *_dl_allocate_tls (void *mem) internal_function;
|
||
rtld_hidden_proto (_dl_allocate_tls)
|
||
|
||
/* Get size and alignment requirements of the static TLS block. */
|
||
extern void _dl_get_tls_static_info (size_t *sizep, size_t *alignp)
|
||
internal_function;
|
||
|
||
extern void _dl_allocate_static_tls (struct link_map *map)
|
||
internal_function attribute_hidden;
|
||
|
||
/* These are internal entry points to the two halves of _dl_allocate_tls,
|
||
only used within rtld.c itself at startup time. */
|
||
extern void *_dl_allocate_tls_storage (void)
|
||
internal_function attribute_hidden;
|
||
extern void *_dl_allocate_tls_init (void *) internal_function;
|
||
rtld_hidden_proto (_dl_allocate_tls_init)
|
||
|
||
/* Deallocate memory allocated with _dl_allocate_tls. */
|
||
extern void _dl_deallocate_tls (void *tcb, bool dealloc_tcb) internal_function;
|
||
rtld_hidden_proto (_dl_deallocate_tls)
|
||
|
||
extern void _dl_nothread_init_static_tls (struct link_map *) attribute_hidden;
|
||
|
||
/* Find origin of the executable. */
|
||
extern const char *_dl_get_origin (void) attribute_hidden;
|
||
|
||
/* Count DSTs. */
|
||
extern size_t _dl_dst_count (const char *name, int is_path) attribute_hidden;
|
||
|
||
/* Substitute DST values. */
|
||
extern char *_dl_dst_substitute (struct link_map *l, const char *name,
|
||
char *result, int is_path) attribute_hidden;
|
||
|
||
/* Check validity of the caller. */
|
||
extern int _dl_check_caller (const void *caller, enum allowmask mask)
|
||
attribute_hidden;
|
||
|
||
/* Open the shared object NAME, relocate it, and run its initializer if it
|
||
hasn't already been run. MODE is as for `dlopen' (see <dlfcn.h>). If
|
||
the object is already opened, returns its existing map. */
|
||
extern void *_dl_open (const char *name, int mode, const void *caller,
|
||
Lmid_t nsid, int argc, char *argv[], char *env[])
|
||
attribute_hidden;
|
||
|
||
/* Free or queue for freeing scope OLD. If other threads might be
|
||
in the middle of _dl_fixup, _dl_profile_fixup or dl*sym using the
|
||
old scope, OLD can't be freed until no thread is using it. */
|
||
extern int _dl_scope_free (void *) attribute_hidden;
|
||
|
||
/* Add module to slot information data. */
|
||
extern void _dl_add_to_slotinfo (struct link_map *l) attribute_hidden;
|
||
|
||
/* Update slot information data for at least the generation of the
|
||
module with the given index. */
|
||
extern struct link_map *_dl_update_slotinfo (unsigned long int req_modid);
|
||
|
||
/* Look up the module's TLS block as for __tls_get_addr,
|
||
but never touch anything. Return null if it's not allocated yet. */
|
||
extern void *_dl_tls_get_addr_soft (struct link_map *l) attribute_hidden;
|
||
|
||
extern int _dl_addr_inside_object (struct link_map *l, const ElfW(Addr) addr)
|
||
internal_function attribute_hidden;
|
||
|
||
/* Show show of an object. */
|
||
extern void _dl_show_scope (struct link_map *new, int from);
|
||
|
||
extern struct link_map *_dl_find_dso_for_object (const ElfW(Addr) addr)
|
||
internal_function;
|
||
rtld_hidden_proto (_dl_find_dso_for_object)
|
||
|
||
/* Initialization which is normally done by the dynamic linker. */
|
||
extern void _dl_non_dynamic_init (void) internal_function;
|
||
|
||
/* Used by static binaries to check the auxiliary vector. */
|
||
extern void _dl_aux_init (ElfW(auxv_t) *av) internal_function;
|
||
|
||
|
||
__END_DECLS
|
||
|
||
#endif /* ldsodefs.h */
|