/* Data structure for communication from the run-time dynamic linker for

   loaded ELF shared objects.

   Copyright (C) 1995-2018 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	_PRIVATE_LINK_H

#define	_PRIVATE_LINK_H	1

#ifdef _LINK_H

# error this should be impossible

#endif

# ifndef _ISOMAC

/* Get most of the contents from the public header, but we define a

   different `struct link_map' type for private use.  The la_objopen

   prototype uses the type, so we have to declare it separately.  */

#  define link_map	link_map_public

#  define la_objopen	la_objopen_wrongproto

# endif

#include <elf/link.h>

# ifndef _ISOMAC

#undef	link_map

#undef	la_objopen

struct link_map;

extern unsigned int la_objopen (struct link_map *__map, Lmid_t __lmid,

				uintptr_t *__cookie);

#include <stdint.h>

#include <stddef.h>

#include <linkmap.h>

#include <dl-fileid.h>

#include <dl-lookupcfg.h>

#include <tls.h>

#include <libc-lock.h>

/* Some internal data structures of the dynamic linker used in the

   linker map.  We only provide forward declarations.  */

struct libname_list;

struct r_found_version;

struct r_search_path_elem;

/* Forward declaration.  */

struct link_map;

/* Structure to describe a single list of scope elements.  The lookup

   functions get passed an array of pointers to such structures.  */

struct r_scope_elem

{

  /* Array of maps for the scope.  */

  struct link_map **r_list;

  /* Number of entries in the scope.  */

  unsigned int r_nlist;

};

/* Structure to record search path and allocation mechanism.  */

struct r_search_path_struct

  {

    struct r_search_path_elem **dirs;

    int malloced;

  };

/* 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 data structures exist in space used by the run-time dynamic linker;

   modifying them may have disastrous results.

   This data structure might change in future, if necessary.  User-level

   programs must avoid defining objects of this type.  */

struct link_map

  {

    /* These first few members are part of the protocol with the debugger.

       This is the same format used in SVR4.  */

    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.  */

    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.  */

    /* This is an element which is only ever different from a pointer to

       the very same copy of this type for ld.so when it is used in more

       than one namespace.  */

    struct link_map *l_real;

    /* Number of the namespace this link map belongs to.  */

    Lmid_t l_ns;

    struct libname_list *l_libname;

    /* Indexed pointers to dynamic section.

       [0,DT_NUM) are indexed by the processor-independent tags.

       [DT_NUM,DT_NUM+DT_THISPROCNUM) are indexed by the tag minus DT_LOPROC.

       [DT_NUM+DT_THISPROCNUM,DT_NUM+DT_THISPROCNUM+DT_VERSIONTAGNUM) are

       indexed by DT_VERSIONTAGIDX(tagvalue).

       [DT_NUM+DT_THISPROCNUM+DT_VERSIONTAGNUM,

	DT_NUM+DT_THISPROCNUM+DT_VERSIONTAGNUM+DT_EXTRANUM) are indexed by

       DT_EXTRATAGIDX(tagvalue).

       [DT_NUM+DT_THISPROCNUM+DT_VERSIONTAGNUM+DT_EXTRANUM,

	DT_NUM+DT_THISPROCNUM+DT_VERSIONTAGNUM+DT_EXTRANUM+DT_VALNUM) are

       indexed by DT_VALTAGIDX(tagvalue) and

       [DT_NUM+DT_THISPROCNUM+DT_VERSIONTAGNUM+DT_EXTRANUM+DT_VALNUM,

	DT_NUM+DT_THISPROCNUM+DT_VERSIONTAGNUM+DT_EXTRANUM+DT_VALNUM+DT_ADDRNUM)

       are indexed by DT_ADDRTAGIDX(tagvalue), see <elf.h>.  */

    ElfW(Dyn) *l_info[DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM

		      + DT_EXTRANUM + DT_VALNUM + DT_ADDRNUM];

    const ElfW(Phdr) *l_phdr;	/* Pointer to program header table in core.  */

    ElfW(Addr) l_entry;		/* Entry point location.  */

    ElfW(Half) l_phnum;		/* Number of program header entries.  */

    ElfW(Half) l_ldnum;		/* Number of dynamic segment entries.  */

    /* Array of DT_NEEDED dependencies and their dependencies, in

       dependency order for symbol lookup (with and without

       duplicates).  There is no entry before the dependencies have

       been loaded.  */

    struct r_scope_elem l_searchlist;

    /* We need a special searchlist to process objects marked with

       DT_SYMBOLIC.  */

    struct r_scope_elem l_symbolic_searchlist;

    /* Dependent object that first caused this object to be loaded.  */

    struct link_map *l_loader;

    /* Array with version names.  */

    struct r_found_version *l_versions;

    unsigned int l_nversions;

    /* Symbol hash table.  */

    Elf_Symndx l_nbuckets;

    Elf32_Word l_gnu_bitmask_idxbits;

    Elf32_Word l_gnu_shift;

    const ElfW(Addr) *l_gnu_bitmask;

    union

    {

      const Elf32_Word *l_gnu_buckets;

      const Elf_Symndx *l_chain;

    };

    union

    {

      const Elf32_Word *l_gnu_chain_zero;

      const Elf_Symndx *l_buckets;

    };

    unsigned int l_direct_opencount; /* Reference count for dlopen/dlclose.  */

    enum			/* Where this object came from.  */

      {

	lt_executable,		/* The main executable program.  */

	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_global:1;	/* Nonzero if object in _dl_global_scope.  */

    unsigned int l_reserved:2;	/* Reserved for internal use.  */

    unsigned int l_phdr_allocated:1; /* Nonzero if the data structure pointed

					to by `l_phdr' is allocated.  */

    unsigned int l_soname_added:1; /* Nonzero if the SONAME is for sure in

				      the l_libname list.  */

    unsigned int l_faked:1;	/* Nonzero if this is a faked descriptor

				   without associated file.  */

    unsigned int l_need_tls_init:1; /* Nonzero if GL(dl_init_static_tls)

				       should be called on this link map

				       when relocation finishes.  */

    unsigned int l_auditing:1;	/* Nonzero if the DSO is used in auditing.  */

    unsigned int l_audit_any_plt:1; /* Nonzero if at least one audit module

				       is interested in the PLT interception.*/

    unsigned int l_removed:1;	/* Nozero if the object cannot be used anymore

				   since it is removed.  */

    unsigned int l_contiguous:1; /* Nonzero if inter-segment holes are

				    mprotected or if no holes are present at

				    all.  */

    unsigned int l_symbolic_in_local_scope:1; /* Nonzero if l_local_scope

						 during LD_TRACE_PRELINKING=1

						 contains any DT_SYMBOLIC

						 libraries.  */

    unsigned int l_free_initfini:1; /* Nonzero if l_initfini can be

				       freed, ie. not allocated with

				       the dummy malloc in ld.so.  */

#include <link_map.h>

    /* Collected information about own RPATH directories.  */

    struct r_search_path_struct l_rpath_dirs;

    /* Collected results of relocation while profiling.  */

    struct reloc_result

    {

      DL_FIXUP_VALUE_TYPE addr;

      struct link_map *bound;

      unsigned int boundndx;

      uint32_t enterexit;

      unsigned int flags;

      /* CONCURRENCY NOTE: This is used to guard the concurrent initialization

	 of the relocation result across multiple threads.  See the more

	 detailed notes in elf/dl-runtime.c.  */

      unsigned int init;

    } *l_reloc_result;

    /* Pointer to the version information if available.  */

    ElfW(Versym) *l_versyms;

    /* String specifying the path where this object was found.  */

    const char *l_origin;

    /* Start and finish of memory map for this object.  l_map_start

       need not be the same as l_addr.  */

    ElfW(Addr) l_map_start, l_map_end;

    /* End of the executable part of the mapping.  */

    ElfW(Addr) l_text_end;

    /* Default array for 'l_scope'.  */

    struct r_scope_elem *l_scope_mem[4];

    /* Size of array allocated for 'l_scope'.  */

    size_t l_scope_max;

    /* This is an array defining the lookup scope for this link map.

       There are initially at most three different scope lists.  */

    struct r_scope_elem **l_scope;

    /* A similar array, this time only with the local scope.  This is

       used occasionally.  */

    struct r_scope_elem *l_local_scope[2];

    /* This information is kept to check for sure whether a shared

       object is the same as one already loaded.  */

    struct r_file_id l_file_id;

    /* Collected information about own RUNPATH directories.  */

    struct r_search_path_struct l_runpath_dirs;

    /* List of object in order of the init and fini calls.  */

    struct link_map **l_initfini;

    /* List of the dependencies introduced through symbol binding.  */

    struct link_map_reldeps

      {

	unsigned int act;

	struct link_map *list[];

      } *l_reldeps;

    unsigned int l_reldepsmax;

    /* Nonzero if the DSO is used.  */

    unsigned int l_used;

    /* Various flag words.  */

    ElfW(Word) l_feature_1;

    ElfW(Word) l_flags_1;

    ElfW(Word) l_flags;

    /* Temporarily used in `dl_close'.  */

    int l_idx;

    struct link_map_machine l_mach;

    struct

    {

      const ElfW(Sym) *sym;

      int type_class;

      struct link_map *value;

      const ElfW(Sym) *ret;

    } l_lookup_cache;

    /* Thread-local storage related info.  */

    /* Start of the initialization image.  */

    void *l_tls_initimage;

    /* Size of the initialization image.  */

    size_t l_tls_initimage_size;

    /* Size of the TLS block.  */

    size_t l_tls_blocksize;

    /* Alignment requirement of the TLS block.  */

    size_t l_tls_align;

    /* Offset of first byte module alignment.  */

    size_t l_tls_firstbyte_offset;

#ifndef NO_TLS_OFFSET

# define NO_TLS_OFFSET	0

#endif

#ifndef FORCED_DYNAMIC_TLS_OFFSET

# if NO_TLS_OFFSET == 0

#  define FORCED_DYNAMIC_TLS_OFFSET -1

# elif NO_TLS_OFFSET == -1

#  define FORCED_DYNAMIC_TLS_OFFSET -2

# else

#  error "FORCED_DYNAMIC_TLS_OFFSET is not defined"

# endif

#endif

    /* For objects present at startup time: offset in the static TLS block.  */

    ptrdiff_t l_tls_offset;

    /* Index of the module in the dtv array.  */

    size_t l_tls_modid;

    /* Number of thread_local objects constructed by this DSO.  This is

       atomically accessed and modified and is not always protected by the load

       lock.  See also: CONCURRENCY NOTES in cxa_thread_atexit_impl.c.  */

    size_t l_tls_dtor_count;

    /* Information used to change permission after the relocations are

       done.  */

    ElfW(Addr) l_relro_addr;

    size_t l_relro_size;

    unsigned long long int l_serial;

    /* Audit information.  This array apparent must be the last in the

       structure.  Never add something after it.  */

    struct auditstate

    {

      uintptr_t cookie;

      unsigned int bindflags;

    } l_audit[0];

  };

#if __ELF_NATIVE_CLASS == 32

# define symbind symbind32

#elif __ELF_NATIVE_CLASS == 64

# define symbind symbind64

#else

# error "__ELF_NATIVE_CLASS must be defined"

#endif

extern int __dl_iterate_phdr (int (*callback) (struct dl_phdr_info *info,

					       size_t size, void *data),

			      void *data);

hidden_proto (__dl_iterate_phdr)

/* We use this macro to refer to ELF macros independent of the native

   wordsize.  `ELFW(R_TYPE)' is used in place of `ELF32_R_TYPE' or

   `ELF64_R_TYPE'.  */

#define ELFW(type)	_ElfW (ELF, __ELF_NATIVE_CLASS, type)

# endif /* !_ISOMAC */

#endif /* include/link.h */