mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-30 08:40:07 +00:00
06535ae948
* posix/unistd.h: Move declaration of __libc_enable_secure to... * include/unistd.h: ...here. * elf/dl-open.c (dl_open_worker): If DST is used in SUID program punt. * elf/dl-deps.c (expand_dst): Likewise. * elf/dynamic-link.h: Set DT_SYMBOLIC, DT_TEXTREL, and DT_BIND_NOW based on DT_FLAGS value. * elf/do-lookup.h: Remove reference_name parameter, add undef_map. Add test for symbols marked STV_HIDDEN. * elf/dl-lookup.c (_dl_lookup_symbol): Remove reference_name parameter, add undef_map. Compute reference_name locally. Update call to do_lookup. (_dl_lookup_symbol_skip): Likewise. (_dl_lookup_versioned_symbol): Likewise. (_dl_lookup_versioned_symbol_skip): Likewise. * elf/dl-libc.c: Update call to _dl_lookup_*symbol. * elf/dl-runtime.c: Likewise. * elf/dl-sym.c: Likewise. * elf/dl-symbol.c: Likewise. * elf/ldsodefs.h: Adjust prototypes. * elf/dl-reloc.c (RESOLV): Add test for STV_PROTECTED flag set and handle appropriately. Add comment about DT_TEXTREL. * elf/dl-runtime.c: Likewise.
401 lines
15 KiB
C
401 lines
15 KiB
C
/* Run-time dynamic linker data structures for loaded ELF shared objects.
|
||
Copyright (C) 1995, 1996, 1997, 1998, 1999 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 Library General Public License as
|
||
published by the Free Software Foundation; either version 2 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
|
||
Library General Public License for more details.
|
||
|
||
You should have received a copy of the GNU Library General Public
|
||
License along with the GNU C Library; see the file COPYING.LIB. If not,
|
||
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
||
Boston, MA 02111-1307, USA. */
|
||
|
||
#ifndef _LDSODEFS_H
|
||
#define _LDSODEFS_H 1
|
||
|
||
#include <features.h>
|
||
|
||
#define __need_size_t
|
||
#define __need_NULL
|
||
#include <stddef.h>
|
||
|
||
#include <elf.h>
|
||
#include <dlfcn.h>
|
||
#include <link.h>
|
||
|
||
__BEGIN_DECLS
|
||
|
||
/* 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)
|
||
|
||
/* 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. */
|
||
};
|
||
|
||
|
||
/* Test whether given NAME matches any of the names of the given object. */
|
||
static __inline int
|
||
__attribute__ ((unused))
|
||
_dl_name_match_p (const char *__name, struct link_map *__map)
|
||
{
|
||
int __found = strcmp (__name, __map->l_name) == 0;
|
||
struct libname_list *__runp = __map->l_libname;
|
||
|
||
while (! __found && __runp != NULL)
|
||
if (strcmp (__name, __runp->name) == 0)
|
||
__found = 1;
|
||
else
|
||
__runp = __runp->next;
|
||
|
||
return __found;
|
||
}
|
||
|
||
/* 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. */
|
||
|
||
|
||
/* Parameters passed to the dynamic linker. */
|
||
extern char **_dl_argv;
|
||
|
||
/* Cached value of `getpagesize ()'. */
|
||
extern size_t _dl_pagesize;
|
||
|
||
/* File descriptor referring to the zero-fill device. */
|
||
extern int _dl_zerofd;
|
||
|
||
/* Name of the shared object to be profiled (if any). */
|
||
extern const char *_dl_profile;
|
||
/* Map of shared object to be profiled. */
|
||
extern struct link_map *_dl_profile_map;
|
||
/* Filename of the output file. */
|
||
extern const char *_dl_profile_output;
|
||
|
||
/* If nonzero the appropriate debug information is printed. */
|
||
extern int _dl_debug_libs;
|
||
extern int _dl_debug_impcalls;
|
||
extern int _dl_debug_bindings;
|
||
extern int _dl_debug_symbols;
|
||
extern int _dl_debug_versions;
|
||
extern int _dl_debug_reloc;
|
||
extern int _dl_debug_files;
|
||
|
||
/* Expect cache ID. */
|
||
extern int _dl_correct_cache_id;
|
||
|
||
/* Mask for hardware capabilities that are available. */
|
||
extern unsigned long int _dl_hwcap;
|
||
|
||
/* Mask for important hardware capabilities we honour. */
|
||
extern unsigned long int _dl_hwcap_mask;
|
||
|
||
/* File descriptor to write debug messages to. */
|
||
extern int _dl_debug_fd;
|
||
|
||
/* Names of shared object for which the RPATH should be ignored. */
|
||
extern const char *_dl_inhibit_rpath;
|
||
|
||
/* OS-dependent function to open the zero-fill device. */
|
||
extern int _dl_sysdep_open_zero_fill (void); /* dl-sysdep.c */
|
||
|
||
/* OS-dependent function to write a message on the specified
|
||
descriptor FD. All arguments are `const char *'; args until a null
|
||
pointer are concatenated to form the message to print. */
|
||
extern void _dl_sysdep_output (int fd, const char *string, ...);
|
||
|
||
/* OS-dependent function to write a debug message on the specified
|
||
descriptor for this. All arguments are `const char *'; args until
|
||
a null pointer are concatenated to form the message to print. If
|
||
NEW_LINE is nonzero it is assumed that the message starts on a new
|
||
line. */
|
||
extern void _dl_debug_message (int new_line, const char *string, ...);
|
||
|
||
/* OS-dependent function to write a message on the standard output.
|
||
All arguments are `const char *'; args until a null pointer
|
||
are concatenated to form the message to print. */
|
||
#define _dl_sysdep_message(string, args...) \
|
||
_dl_sysdep_output (STDOUT_FILENO, string, ##args)
|
||
|
||
/* OS-dependent function to write a message on the standard error.
|
||
All arguments are `const char *'; args until a null pointer
|
||
are concatenated to form the message to print. */
|
||
#define _dl_sysdep_error(string, args...) \
|
||
_dl_sysdep_output (STDERR_FILENO, string, ##args)
|
||
|
||
/* OS-dependent function to give a fatal error message and exit
|
||
when the dynamic linker fails before the program is fully linked.
|
||
All arguments are `const char *'; args until a null pointer
|
||
are concatenated to form the message to print. */
|
||
#define _dl_sysdep_fatal(string, args...) \
|
||
do \
|
||
{ \
|
||
_dl_sysdep_output (STDERR_FILENO, string, ##args); \
|
||
_exit (127); \
|
||
} \
|
||
while (1)
|
||
|
||
/* Nonzero if the program should be "secure" (i.e. it's setuid or somesuch).
|
||
This tells the dynamic linker to ignore environment variables. */
|
||
extern int _dl_secure;
|
||
|
||
/* 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 *errstring)
|
||
internal_function
|
||
__attribute__ ((__noreturn__));
|
||
|
||
/* 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 *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.
|
||
For preloaded shared objects PRELOADED is set to a non-zero
|
||
value to allow additional security checks. */
|
||
extern struct link_map *_dl_map_object (struct link_map *loader,
|
||
const char *name, int preloaded,
|
||
int type, int trace_mode)
|
||
internal_function;
|
||
|
||
/* 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 unsigned int _dl_map_object_deps (struct link_map *map,
|
||
struct link_map **preloads,
|
||
unsigned int npreloads,
|
||
int trace_mode, int global_scope)
|
||
internal_function;
|
||
|
||
/* Cache the locations of MAP's hash table. */
|
||
extern void _dl_setup_hash (struct link_map *map) 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.
|
||
RELOC_TYPE is a machine-dependent reloc type, which is passed to
|
||
the `elf_machine_lookup_*_p' macros in dl-machine.h to affect which
|
||
symbols can be chosen. */
|
||
extern ElfW(Addr) _dl_lookup_symbol (const char *undef,
|
||
struct link_map *undef_map,
|
||
const ElfW(Sym) **sym,
|
||
struct r_scope_elem *symbol_scope[],
|
||
int reloc_type)
|
||
internal_function;
|
||
|
||
/* Lookup versioned symbol. */
|
||
extern ElfW(Addr) _dl_lookup_versioned_symbol (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 reloc_type)
|
||
internal_function;
|
||
|
||
/* For handling RTLD_NEXT we must be able to skip shared objects. */
|
||
extern ElfW(Addr) _dl_lookup_symbol_skip (const char *undef,
|
||
struct link_map *undef_map,
|
||
const ElfW(Sym) **sym,
|
||
struct r_scope_elem *symbol_scope[],
|
||
struct link_map *skip_this)
|
||
internal_function;
|
||
|
||
/* For handling RTLD_NEXT with versioned symbols we must be able to
|
||
skip shared objects. */
|
||
extern ElfW(Addr) _dl_lookup_versioned_symbol_skip (const char *undef,
|
||
struct link_map *undef_map,
|
||
const ElfW(Sym) **sym,
|
||
struct r_scope_elem *symbol_scope[],
|
||
const struct r_found_version *version,
|
||
struct link_map *skip_this)
|
||
internal_function;
|
||
|
||
/* 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;
|
||
|
||
|
||
/* Structure describing the dynamic linker itself. */
|
||
extern struct link_map _dl_rtld_map;
|
||
/* And a pointer to the map for the main map. */
|
||
extern struct link_map *_dl_loaded;
|
||
/* Array representing global scope. */
|
||
extern struct r_scope_elem *_dl_global_scope[2];
|
||
/* Direct pointer to the searchlist of the main object. */
|
||
extern struct r_scope_elem *_dl_main_searchlist;
|
||
/* Copy of the content of `_dl_main_searchlist'. */
|
||
extern struct r_scope_elem _dl_initial_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. */
|
||
extern size_t _dl_global_scope_alloc;
|
||
|
||
/* Allocate a `struct link_map' for a new object being loaded,
|
||
and enter it into the _dl_main_map list. */
|
||
extern struct link_map *_dl_new_object (char *realname, const char *libname,
|
||
int type, struct link_map *loader)
|
||
internal_function;
|
||
|
||
/* Relocate the given object (if it hasn't already been).
|
||
SCOPE is passed to _dl_lookup_symbol in symbol lookups.
|
||
If LAZY is nonzero, don't relocate its PLT. */
|
||
extern void _dl_relocate_object (struct link_map *map,
|
||
struct r_scope_elem *scope[],
|
||
int lazy, int consider_profiling);
|
||
|
||
/* 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,
|
||
uint_fast8_t type, int plt)
|
||
internal_function;
|
||
|
||
/* 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)
|
||
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)
|
||
internal_function;
|
||
|
||
/* Return the address of the next initializer function for SCOPE or one of
|
||
its dependencies that has not yet been run. When there are no more
|
||
initializers to be run, this returns zero. The functions are returned
|
||
in the order they should be called. */
|
||
extern ElfW(Addr) _dl_init_next (struct r_scope_elem *scope) internal_function;
|
||
|
||
/* Call the finalizer functions of all shared objects whose
|
||
initializer functions have completed. */
|
||
extern void _dl_fini (void) 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);
|
||
|
||
/* 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)
|
||
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 (struct link_map *map, const char *output_dir)
|
||
internal_function;
|
||
|
||
/* The actual functions used to keep book on the calls. */
|
||
extern void _dl_mcount (ElfW(Addr) frompc, ElfW(Addr) selfpc);
|
||
|
||
/* 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;
|
||
|
||
__END_DECLS
|
||
|
||
#endif /* ldsodefs.h */
|