-/* Run-time dynamic linker data structures for loaded ELF shared objects.
-Copyright (C) 1995, 1996 Free Software Foundation, Inc.
-This file is part of the GNU C Library.
+/* Data structure for communication from the run-time dynamic linker 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 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 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
-Library General Public License for more details.
+ 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 Library General Public
-License along with the GNU C Library; see the file COPYING.LIB. If
-not, write to the Free Software Foundation, Inc., 675 Mass Ave,
-Cambridge, MA 02139, USA. */
+ 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 _LINK_H
#define _LINK_H 1
+#include <features.h>
#include <elf.h>
+#include <dlfcn.h>
+#include <sys/types.h>
+/* 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)
+#define _ElfW(e,w,t) _ElfW_1 (e, w, _##t)
+#define _ElfW_1(e,w,t) e##w##t
+
+#include <bits/elfclass.h> /* Defines __ELF_NATIVE_CLASS. */
+#include <bits/link.h>
/* Rendezvous structure used by the run-time dynamic linker to communicate
details of shared object loading to the debugger. If the executable's
library or unmap it, and again when the mapping change is complete.
The debugger can set a breakpoint at this address if it wants to
notice shared object mapping changes. */
- Elf32_Addr r_brk;
+ ElfW(Addr) r_brk;
enum
{
/* This state value describes the mapping change taking place when
the `r_brk' address is called. */
RT_CONSISTENT, /* Mapping change is complete. */
RT_ADD, /* Beginning to add a new object. */
- RT_DELETE, /* Beginning to remove an object mapping. */
+ RT_DELETE /* Beginning to remove an object mapping. */
} r_state;
- Elf32_Addr r_ldbase; /* Base address the linker is loaded at. */
+ ElfW(Addr) r_ldbase; /* Base address the linker is loaded at. */
};
+/* This is the instance of that structure used by the dynamic linker. */
+extern struct r_debug _r_debug;
+
/* This symbol refers to the "dynamic structure" in the `.dynamic' section
of whatever module refers to `_DYNAMIC'. So, to find its own
`struct r_debug', a program could do:
- for (dyn = _DYNAMIC; dyn->d_tag != DT_NULL)
- if (dyn->d_tag == DT_DEBUG) r_debug = (struct r_debug) dyn->d_un.d_ptr;
+ for (dyn = _DYNAMIC; dyn->d_tag != DT_NULL; ++dyn)
+ if (dyn->d_tag == DT_DEBUG)
+ r_debug = (struct r_debug *) dyn->d_un.d_ptr;
*/
-
-extern Elf32_Dyn _DYNAMIC[];
-
+extern ElfW(Dyn) _DYNAMIC[];
/* Structure describing a loaded shared object. The `l_next' and `l_prev'
members form a chain of all the shared objects loaded at startup.
/* These first few members are part of the protocol with the debugger.
This is the same format used in SVR4. */
- Elf32_Addr l_addr; /* Base address shared object is loaded at. */
+ ElfW(Addr) l_addr; /* Difference between the address in the ELF
+ file and the addresses in memory. */
char *l_name; /* Absolute file name object was found in. */
- Elf32_Dyn *l_ld; /* Dynamic section of the shared object. */
+ ElfW(Dyn) *l_ld; /* Dynamic section of the shared object. */
struct link_map *l_next, *l_prev; /* Chain of loaded objects. */
+ };
- /* All following members are internal to the dynamic linker.
- They may change without notice. */
-
- const char *l_libname; /* Name requested (before search). */
- /* Indexed pointers to dynamic section.
- [0,DT_NUM) are indexed by the processor-independent tags.
- [DT_NUM,DT_NUM+DT_PROCNUM] are indexed by the tag minus DT_LOPROC. */
- Elf32_Dyn *l_info[DT_NUM + DT_PROCNUM];
- const Elf32_Phdr *l_phdr; /* Pointer to program header table in core. */
- Elf32_Word l_phnum; /* Number of program header entries. */
- Elf32_Addr l_entry; /* Entry point location. */
-
- /* Array of DT_NEEDED dependencies and their dependencies, in
- dependency order for symbol lookup. This is null before the
- dependencies have been loaded. */
- struct link_map **l_searchlist;
- unsigned int l_nsearchlist;
-
- /* Symbol hash table. */
- Elf32_Word l_nbuckets;
- const Elf32_Word *l_buckets, *l_chain;
-
- unsigned int l_opencount; /* Reference count for dlopen/dlclose. */
- enum /* Where this object came from. */
- {
- lt_executable, /* The main executable program. */
- lt_interpreter, /* The interpreter: the dynamic linker. */
- lt_library, /* Library needed by main executable. */
- lt_loaded, /* Extra run-time loaded shared object. */
- } l_type:2;
- unsigned int l_relocated:1; /* Nonzero if object's relocations done. */
- unsigned int l_init_called:1; /* Nonzero if DT_INIT function called. */
- unsigned int l_init_running:1; /* Nonzero while DT_INIT function runs. */
+#ifdef __USE_GNU
+
+/* Version numbers for la_version handshake interface. */
+#define LAV_CURRENT 1
+
+/* Activity types signaled through la_activity. */
+enum
+ {
+ LA_ACT_CONSISTENT, /* Link map consistent again. */
+ LA_ACT_ADD, /* New object will be added. */
+ LA_ACT_DELETE /* Objects will be removed. */
+ };
+
+/* Values representing origin of name for dynamic loading. */
+enum
+ {
+ LA_SER_ORIG = 0x01, /* Original name. */
+ LA_SER_LIBPATH = 0x02, /* Directory from LD_LIBRARY_PATH. */
+ LA_SER_RUNPATH = 0x04, /* Directory from RPATH/RUNPATH. */
+ LA_SER_CONFIG = 0x08, /* Found through ldconfig. */
+ LA_SER_DEFAULT = 0x40, /* Default directory. */
+ LA_SER_SECURE = 0x80 /* Unused. */
+ };
+
+/* Values for la_objopen return value. */
+enum
+ {
+ LA_FLG_BINDTO = 0x01, /* Audit symbols bound to this object. */
+ LA_FLG_BINDFROM = 0x02 /* Audit symbols bound from this object. */
+ };
+
+/* Values for la_symbind flags parameter. */
+enum
+ {
+ LA_SYMB_NOPLTENTER = 0x01, /* la_pltenter will not be called. */
+ LA_SYMB_NOPLTEXIT = 0x02, /* la_pltexit will not be called. */
+ LA_SYMB_STRUCTCALL = 0x04, /* Return value is a structure. */
+ LA_SYMB_DLSYM = 0x08, /* Binding due to dlsym call. */
+ LA_SYMB_ALTVALUE = 0x10 /* Value has been changed by a previous
+ la_symbind call. */
+ };
+
+struct dl_phdr_info
+ {
+ ElfW(Addr) dlpi_addr;
+ const char *dlpi_name;
+ const ElfW(Phdr) *dlpi_phdr;
+ ElfW(Half) dlpi_phnum;
+
+ /* Note: Following members were introduced after the first
+ version of this structure was available. Check the SIZE
+ argument passed to the dl_iterate_phdr callback to determine
+ whether or not each later member is available. */
+
+ /* Incremented when a new object may have been added. */
+ __extension__ unsigned long long int dlpi_adds;
+ /* Incremented when an object may have been removed. */
+ __extension__ unsigned long long int dlpi_subs;
+
+ /* If there is a PT_TLS segment, its module ID as used in
+ TLS relocations, else zero. */
+ size_t dlpi_tls_modid;
+
+ /* The address of the calling thread's instance of this module's
+ PT_TLS segment, if it has one and it has been allocated
+ in the calling thread, otherwise a null pointer. */
+ void *dlpi_tls_data;
};
-\f
-/* 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. */
-
-
-/* File descriptor referring to the zero-fill device. */
-extern int _dl_zerofd;
-
-/* 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 standard output.
- All arguments are `const char *'; args until a null pointer
- are concatenated to form the message to print. */
-extern void _dl_sysdep_message (const char *string, ...);
-
-/* 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. */
-extern void _dl_sysdep_fatal (const char *string, ...)
- __attribute__ ((__noreturn__));
-
-/* 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)
- __attribute__ ((__noreturn__));
-
-/* Call OPERATE, catching errors from `dl_signal_error'. If there is no
- error, *ERRSTRING is set to null. If there is an error, *ERRSTRING and
- *OBJECT are set to the strings passed to _dl_signal_error, and the error
- code passed is the return value. */
-extern int _dl_catch_error (const char **errstring,
- const char **object,
- void (*operate) (void));
-
-
-/* Helper function for <dlfcn.h> functions. Runs the OPERATE function via
- _dl_catch_error. Returns zero for success, nonzero for failure; and
- arranges for `dlerror' to return the error details. */
-extern int _dlerror_run (void (*operate) (void));
-
-
-/* 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);
-
-/* Similar, but file found at REALNAME and opened on FD.
- REALNAME must malloc'd storage and is used in internal data structures. */
-extern struct link_map *_dl_map_object_from_fd (const char *name,
- int fd, char *realname);
-
-/* Call _dl_map_object on the dependencies of MAP, and
- set up MAP->l_searchlist. */
-extern void _dl_map_object_deps (struct link_map *map);
-
-/* Cache the locations of MAP's hash table. */
-extern void _dl_setup_hash (struct link_map *map);
-
-
-/* Open the shared object NAME, relocate it, and run its initializer if it
- hasn't already been run. LOADER's DT_RPATH is used in searching for
- NAME. MODE is as for `dlopen' (see <dlfcn.h>). If the object is
- already opened, returns its existing map. */
-extern struct link_map *_dl_open (struct link_map *loader,
- const char *name, int mode);
-
-
-
-/* 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. Each of SYMBOL_SCOPE[0] and
- SYMBOL_SCOPE[1] that is not null and their dependencies are searched to
- resolve the name. REFERENCE_NAME should name the object containing the
- reference; it is used in error messages. RELOC_ADDR is the address
- being fixed up and the chosen symbol cannot be one with this value. If
- NOPLT is nonzero, then the reference must not be resolved to a PLT
- entry. */
-extern Elf32_Addr _dl_lookup_symbol (const char *undef,
- const Elf32_Sym **sym,
- struct link_map *symbol_scope[2],
- const char *reference_name,
- Elf32_Addr reloc_addr,
- int noplt);
-
-
-/* List of objects currently loaded. */
-extern struct link_map *_dl_loaded;
-
-/* Tail of that list which were loaded at startup. */
-extern struct link_map *_dl_startup_loaded;
-
-/* Allocate a `struct link_map' for a new object being loaded,
- and enter it into the _dl_loaded list. */
-extern struct link_map *_dl_new_object (char *realname, const char *libname,
- int type);
-
-/* Relocate the given object (if it hasn't already been).
- If LAZY is nonzero, don't relocate its PLT. */
-extern void _dl_relocate_object (struct link_map *map, int lazy);
-
-/* Return the address of the next initializer function not yet 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 Elf32_Addr _dl_init_next (void);
-
-/* Call the finalizer functions of all shared objects whose
- initializer functions have completed. */
-extern void _dl_fini (void);
-
-/* 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_r_debug_state (void);
+__BEGIN_DECLS
+
+extern int dl_iterate_phdr (int (*__callback) (struct dl_phdr_info *,
+ size_t, void *),
+ void *__data);
+
+
+/* Prototypes for the ld.so auditing interfaces. These are not
+ defined anywhere in ld.so but instead have to be provided by the
+ auditing DSO. */
+extern unsigned int la_version (unsigned int __version);
+extern void la_activity (uintptr_t *__cookie, unsigned int __flag);
+extern char *la_objsearch (const char *__name, uintptr_t *__cookie,
+ unsigned int __flag);
+extern unsigned int la_objopen (struct link_map *__map, Lmid_t __lmid,
+ uintptr_t *__cookie);
+extern void la_preinit (uintptr_t *__cookie);
+extern uintptr_t la_symbind32 (Elf32_Sym *__sym, unsigned int __ndx,
+ uintptr_t *__refcook, uintptr_t *__defcook,
+ unsigned int *__flags, const char *__symname);
+extern uintptr_t la_symbind64 (Elf64_Sym *__sym, unsigned int __ndx,
+ uintptr_t *__refcook, uintptr_t *__defcook,
+ unsigned int *__flags, const char *__symname);
+extern unsigned int la_objclose (uintptr_t *__cookie);
+
+__END_DECLS
+
+#endif
#endif /* link.h */