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144761540a
It is solely for prelink with PIE executables [1]. [1] https://sourceware.org/legacy-ml/libc-hacker/2003-11/msg00127.html Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
1473 lines
53 KiB
C++
1473 lines
53 KiB
C++
/* Run-time dynamic linker data structures for loaded ELF shared objects.
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Copyright (C) 1995-2022 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<https://www.gnu.org/licenses/>. */
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#ifndef _LDSODEFS_H
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#define _LDSODEFS_H 1
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#include <features.h>
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#include <stdbool.h>
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#define __need_size_t
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#define __need_NULL
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#include <stddef.h>
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#include <string.h>
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#include <stdint.h>
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#include <elf.h>
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#include <dlfcn.h>
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#include <fpu_control.h>
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#include <sys/mman.h>
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#include <link.h>
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#include <dl-lookupcfg.h>
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#include <dl-sysdep.h>
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#include <dl-fixup-attribute.h>
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#include <libc-lock.h>
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#include <hp-timing.h>
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#include <tls.h>
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#include <list_t.h>
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__BEGIN_DECLS
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#define VERSYMIDX(sym) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGIDX (sym))
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#define VALIDX(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM \
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+ DT_EXTRANUM + DT_VALTAGIDX (tag))
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#define ADDRIDX(tag) (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGNUM \
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+ DT_EXTRANUM + DT_VALNUM + DT_ADDRTAGIDX (tag))
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/* Type of GNU hash which the machine uses. */
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#ifndef ELF_MACHINE_GNU_HASH_ADDRIDX
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# define ELF_MACHINE_GNU_HASH_ADDRIDX ADDRIDX (DT_GNU_HASH)
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#endif
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/* Calculate the index of a symbol in GNU hash. */
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#ifndef ELF_MACHINE_HASH_SYMIDX
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# define ELF_MACHINE_HASH_SYMIDX(map, hasharr) \
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((hasharr) - (map)->l_gnu_chain_zero)
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#endif
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/* Setup MIPS xhash. Defined only for MIPS. */
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#ifndef ELF_MACHINE_XHASH_SETUP
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# define ELF_MACHINE_XHASH_SETUP(hash32, symbias, map) \
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((void) (hash32), (void) (symbias), (void) (map))
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#endif
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/* We use this macro to refer to ELF types independent of the native wordsize.
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`ElfW(TYPE)' is used in place of `Elf32_TYPE' or `Elf64_TYPE'. */
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#define ELFW(type) _ElfW (ELF, __ELF_NATIVE_CLASS, type)
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/* Return true if dynamic section in the shared library L should be
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relocated. */
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static inline bool
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dl_relocate_ld (const struct link_map *l)
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{
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/* Don't relocate dynamic section if it is readonly */
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return !(l->l_ld_readonly || DL_RO_DYN_SECTION);
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}
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/* All references to the value of l_info[DT_PLTGOT],
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l_info[DT_STRTAB], l_info[DT_SYMTAB], l_info[DT_RELA],
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l_info[DT_REL], l_info[DT_JMPREL], and l_info[VERSYMIDX (DT_VERSYM)]
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have to be accessed via the D_PTR macro. The macro is needed since for
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most architectures the entry is already relocated - but for some not
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and we need to relocate at access time. */
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#define D_PTR(map, i) \
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((map)->i->d_un.d_ptr + (dl_relocate_ld (map) ? 0 : (map)->l_addr))
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/* Result of the lookup functions and how to retrieve the base address. */
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typedef struct link_map *lookup_t;
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#define LOOKUP_VALUE(map) map
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#define LOOKUP_VALUE_ADDRESS(map, set) ((set) || (map) ? (map)->l_addr : 0)
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/* Calculate the address of symbol REF using the base address from map MAP,
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if non-NULL. Don't check for NULL map if MAP_SET is TRUE. */
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#define SYMBOL_ADDRESS(map, ref, map_set) \
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((ref) == NULL ? 0 \
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: (__glibc_unlikely ((ref)->st_shndx == SHN_ABS) ? 0 \
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: LOOKUP_VALUE_ADDRESS (map, map_set)) + (ref)->st_value)
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/* Type of a constructor function, in DT_INIT, DT_INIT_ARRAY,
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DT_PREINIT_ARRAY. */
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typedef void (*dl_init_t) (int, char **, char **);
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/* On some architectures a pointer to a function is not just a pointer
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to the actual code of the function but rather an architecture
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specific descriptor. */
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#ifndef ELF_FUNCTION_PTR_IS_SPECIAL
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# define DL_SYMBOL_ADDRESS(map, ref) \
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(void *) SYMBOL_ADDRESS (map, ref, false)
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# define DL_LOOKUP_ADDRESS(addr) ((ElfW(Addr)) (addr))
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# define DL_CALL_DT_INIT(map, start, argc, argv, env) \
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((dl_init_t) (start)) (argc, argv, env)
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# define DL_CALL_DT_FINI(map, start) ((fini_t) (start)) ()
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#endif
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/* On some architectures dladdr can't use st_size of all symbols this way. */
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#define DL_ADDR_SYM_MATCH(L, SYM, MATCHSYM, ADDR) \
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((ADDR) >= (L)->l_addr + (SYM)->st_value \
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&& ((((SYM)->st_shndx == SHN_UNDEF || (SYM)->st_size == 0) \
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&& (ADDR) == (L)->l_addr + (SYM)->st_value) \
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|| (ADDR) < (L)->l_addr + (SYM)->st_value + (SYM)->st_size) \
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&& ((MATCHSYM) == NULL || (MATCHSYM)->st_value < (SYM)->st_value))
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/* According to the ELF gABI no STV_HIDDEN or STV_INTERNAL symbols are
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expected to be present in dynamic symbol tables as they should have
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been either removed or converted to STB_LOCAL binding by the static
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linker. However some GNU binutils versions produce such symbols in
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some cases. To prevent such symbols present in a buggy binary from
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preempting global symbols we filter them out with this predicate. */
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static __always_inline bool
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dl_symbol_visibility_binds_local_p (const ElfW(Sym) *sym)
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{
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return (ELFW(ST_VISIBILITY) (sym->st_other) == STV_HIDDEN
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|| ELFW(ST_VISIBILITY) (sym->st_other) == STV_INTERNAL);
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}
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/* Unmap a loaded object, called by _dl_close (). */
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#ifndef DL_UNMAP_IS_SPECIAL
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# define DL_UNMAP(map) _dl_unmap_segments (map)
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#endif
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/* Reloc type classes as returned by elf_machine_type_class().
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ELF_RTYPE_CLASS_PLT means this reloc should not be satisfied by
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some PLT symbol, ELF_RTYPE_CLASS_COPY means this reloc should not be
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satisfied by any symbol in the executable. Some architectures do
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not support copy relocations. In this case we define the macro to
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zero so that the code for handling them gets automatically optimized
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out. ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA means address of protected
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data defined in the shared library may be external, i.e., due to copy
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relocation. */
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#define ELF_RTYPE_CLASS_PLT 1
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#ifndef DL_NO_COPY_RELOCS
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# define ELF_RTYPE_CLASS_COPY 2
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#else
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# define ELF_RTYPE_CLASS_COPY 0
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#endif
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/* If DL_EXTERN_PROTECTED_DATA is defined, address of protected data
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defined in the shared library may be external, i.e., due to copy
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relocation. */
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#ifdef DL_EXTERN_PROTECTED_DATA
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# define ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA 4
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#else
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# define ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA 0
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#endif
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/* ELF uses the PF_x macros to specify the segment permissions, mmap
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uses PROT_xxx. In most cases the three macros have the values 1, 2,
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and 3 but not in a matching order. The following macros allows
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converting from the PF_x values to PROT_xxx values. */
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#define PF_TO_PROT \
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((PROT_READ << (PF_R * 4)) \
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| (PROT_WRITE << (PF_W * 4)) \
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| (PROT_EXEC << (PF_X * 4)) \
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| ((PROT_READ | PROT_WRITE) << ((PF_R | PF_W) * 4)) \
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| ((PROT_READ | PROT_EXEC) << ((PF_R | PF_X) * 4)) \
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| ((PROT_WRITE | PROT_EXEC) << (PF_W | PF_X) * 4) \
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| ((PROT_READ | PROT_WRITE | PROT_EXEC) << ((PF_R | PF_W | PF_X) * 4)))
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/* The filename itself, or the main program name, if available. */
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#define DSO_FILENAME(name) ((name)[0] ? (name) \
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: (rtld_progname ?: "<main program>"))
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#define RTLD_PROGNAME (rtld_progname ?: "<program name unknown>")
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/* For the version handling we need an array with only names and their
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hash values. */
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struct r_found_version
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{
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const char *name;
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ElfW(Word) hash;
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int hidden;
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const char *filename;
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};
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/* We want to cache information about the searches for shared objects. */
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enum r_dir_status { unknown, nonexisting, existing };
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struct r_search_path_elem
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{
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/* This link is only used in the `all_dirs' member of `r_search_path'. */
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struct r_search_path_elem *next;
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/* Strings saying where the definition came from. */
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const char *what;
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const char *where;
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/* Basename for this search path element. The string must end with
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a slash character. */
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const char *dirname;
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size_t dirnamelen;
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enum r_dir_status status[0];
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};
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struct r_strlenpair
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{
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const char *str;
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size_t len;
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};
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/* A data structure for a simple single linked list of strings. */
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struct libname_list
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{
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const char *name; /* Name requested (before search). */
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struct libname_list *next; /* Link to next name for this object. */
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int dont_free; /* Flag whether this element should be freed
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if the object is not entirely unloaded. */
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};
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/* Bit masks for the objects which valid callers can come from to
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functions with restricted interface. */
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enum allowmask
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{
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allow_libc = 1,
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allow_libdl = 2,
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allow_libpthread = 4,
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allow_ldso = 8
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};
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/* DSO sort algorithm to use (check dl-sort-maps.c). */
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enum dso_sort_algorithm
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{
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dso_sort_algorithm_original,
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dso_sort_algorithm_dfs
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};
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struct audit_ifaces
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{
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void (*activity) (uintptr_t *, unsigned int);
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char *(*objsearch) (const char *, uintptr_t *, unsigned int);
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unsigned int (*objopen) (struct link_map *, Lmid_t, uintptr_t *);
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void (*preinit) (uintptr_t *);
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union
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{
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uintptr_t (*symbind32) (Elf32_Sym *, unsigned int, uintptr_t *,
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uintptr_t *, unsigned int *, const char *);
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uintptr_t (*symbind64) (Elf64_Sym *, unsigned int, uintptr_t *,
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uintptr_t *, unsigned int *, const char *);
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};
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union
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{
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#ifdef ARCH_PLTENTER_MEMBERS
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ARCH_PLTENTER_MEMBERS;
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#endif
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};
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union
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{
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#ifdef ARCH_PLTEXIT_MEMBERS
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ARCH_PLTEXIT_MEMBERS;
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#endif
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};
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unsigned int (*objclose) (uintptr_t *);
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struct audit_ifaces *next;
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};
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/* Test whether given NAME matches any of the names of the given object. */
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extern int _dl_name_match_p (const char *__name, const struct link_map *__map)
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attribute_hidden;
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/* Compute next higher prime number. */
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extern unsigned long int _dl_higher_prime_number (unsigned long int n)
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attribute_hidden;
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/* A stripped down strtoul-like implementation. */
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uint64_t _dl_strtoul (const char *, char **) attribute_hidden;
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/* Function used as argument for `_dl_receive_error' function. The
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arguments are the error code, error string, and the objname the
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error occurred in. */
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typedef void (*receiver_fct) (int, const char *, const char *);
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/* Internal functions of the run-time dynamic linker.
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These can be accessed if you link again the dynamic linker
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as a shared library, as in `-lld' or `/lib/ld.so' explicitly;
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but are not normally of interest to user programs.
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The `-ldl' library functions in <dlfcn.h> provide a simple
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user interface to run-time dynamic linking. */
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#ifndef SHARED
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# define EXTERN extern
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# define GL(name) _##name
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#else
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# define EXTERN
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# if IS_IN (rtld)
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# define GL(name) _rtld_local._##name
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# else
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# define GL(name) _rtld_global._##name
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# endif
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struct rtld_global
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{
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#endif
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/* Don't change the order of the following elements. 'dl_loaded'
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must remain the first element. Forever. */
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/* Non-shared code has no support for multiple namespaces. */
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#ifdef SHARED
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# define DL_NNS 16
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#else
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# define DL_NNS 1
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#endif
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EXTERN struct link_namespaces
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{
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/* A pointer to the map for the main map. */
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struct link_map *_ns_loaded;
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/* Number of object in the _dl_loaded list. */
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unsigned int _ns_nloaded;
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/* Direct pointer to the searchlist of the main object. */
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struct r_scope_elem *_ns_main_searchlist;
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/* This is zero at program start to signal that the global scope map is
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allocated by rtld. Later it keeps the size of the map. It might be
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reset if in _dl_close if the last global object is removed. */
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unsigned int _ns_global_scope_alloc;
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/* During dlopen, this is the number of objects that still need to
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be added to the global scope map. It has to be taken into
|
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account when resizing the map, for future map additions after
|
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recursive dlopen calls from ELF constructors. */
|
||
unsigned int _ns_global_scope_pending_adds;
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|
||
/* Once libc.so has been loaded into the namespace, this points to
|
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its link map. */
|
||
struct link_map *libc_map;
|
||
|
||
/* Search table for unique objects. */
|
||
struct unique_sym_table
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||
{
|
||
__rtld_lock_define_recursive (, lock)
|
||
struct unique_sym
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||
{
|
||
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_extended _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)
|
||
/* This lock protects global and module specific TLS related data.
|
||
E.g. it is held in dlopen and dlclose when GL(dl_tls_generation),
|
||
GL(dl_tls_max_dtv_idx) or GL(dl_tls_dtv_slotinfo_list) are
|
||
accessed and when TLS related relocations are processed for a
|
||
module. It was introduced to keep pthread_create accessing TLS
|
||
state that is being set up. */
|
||
__rtld_lock_define_recursive (EXTERN, _dl_load_tls_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;
|
||
|
||
/* 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;
|
||
|
||
/* Structure describing the dynamic linker itself. */
|
||
EXTERN struct link_map _dl_rtld_map;
|
||
#ifdef SHARED
|
||
/* Used to store the audit information for the link map of the
|
||
dynamic loader. */
|
||
struct auditstate _dl_rtld_auditstate[DL_NNS];
|
||
#endif
|
||
|
||
#if !PTHREAD_IN_LIBC && defined SHARED \
|
||
&& defined __rtld_lock_default_lock_recursive
|
||
EXTERN void (*_dl_rtld_lock_recursive) (void *);
|
||
EXTERN void (*_dl_rtld_unlock_recursive) (void *);
|
||
#endif
|
||
|
||
/* Get architecture specific definitions. */
|
||
#define PROCINFO_DECL
|
||
#ifndef PROCINFO_CLASS
|
||
# define PROCINFO_CLASS EXTERN
|
||
#endif
|
||
#include <dl-procruntime.c>
|
||
|
||
#if !PTHREAD_IN_LIBC
|
||
/* 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 **);
|
||
#endif
|
||
|
||
/* 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[];
|
||
} *_dl_tls_dtv_slotinfo_list;
|
||
/* Number of modules in the static TLS block. */
|
||
EXTERN size_t _dl_tls_static_nelem;
|
||
/* Size actually allocated in the static TLS block. */
|
||
EXTERN size_t _dl_tls_static_used;
|
||
/* Remaining amount of static TLS that may be used for optimizing
|
||
dynamic TLS access (e.g. with TLSDESC). */
|
||
EXTERN size_t _dl_tls_static_optional;
|
||
|
||
/* 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;
|
||
|
||
#if !PTHREAD_IN_LIBC
|
||
EXTERN void (*_dl_init_static_tls) (struct link_map *);
|
||
#endif
|
||
|
||
/* Scopes to free after next THREAD_GSCOPE_WAIT (). */
|
||
EXTERN struct dl_scope_free_list
|
||
{
|
||
size_t count;
|
||
void *list[50];
|
||
} *_dl_scope_free_list;
|
||
#if PTHREAD_IN_LIBC
|
||
/* List of active thread stacks, with memory managed by glibc. */
|
||
EXTERN list_t _dl_stack_used;
|
||
|
||
/* List of thread stacks that were allocated by the application. */
|
||
EXTERN list_t _dl_stack_user;
|
||
|
||
/* List of queued thread stacks. */
|
||
EXTERN list_t _dl_stack_cache;
|
||
|
||
/* Total size of all stacks in the cache (sum over stackblock_size). */
|
||
EXTERN size_t _dl_stack_cache_actsize;
|
||
|
||
/* We need to record what list operations we are going to do so
|
||
that, in case of an asynchronous interruption due to a fork()
|
||
call, we can correct for the work. */
|
||
EXTERN uintptr_t _dl_in_flight_stack;
|
||
|
||
/* Mutex protecting the stack lists. */
|
||
EXTERN int _dl_stack_cache_lock;
|
||
#else
|
||
/* The total number of thread IDs currently in use, or on the list of
|
||
available thread IDs. */
|
||
EXTERN int _dl_pthread_num_threads;
|
||
|
||
/* Array of __pthread structures and its lock. */
|
||
EXTERN struct __pthread **_dl_pthread_threads;
|
||
__libc_rwlock_define (EXTERN, _dl_pthread_threads_lock)
|
||
#endif
|
||
#ifdef SHARED
|
||
};
|
||
# define __rtld_global_attribute__
|
||
# if 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
|
||
# if 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)
|
||
|
||
/* 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;
|
||
|
||
/* Cached value of `sysconf (_SC_MINSIGSTKSZ)'. */
|
||
EXTERN size_t _dl_minsigstacksize;
|
||
|
||
/* 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;
|
||
|
||
#if !HAVE_TUNABLES
|
||
/* Mask for important hardware capabilities we honour. */
|
||
EXTERN uint64_t _dl_hwcap_mask;
|
||
#endif
|
||
|
||
#ifdef HAVE_AUX_VECTOR
|
||
/* Pointer to the auxv list supplied to the program at startup. */
|
||
EXTERN ElfW(auxv_t) *_dl_auxv;
|
||
#endif
|
||
|
||
/* Get architecture specific definitions. */
|
||
#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;
|
||
|
||
/* Size of the static TLS block. */
|
||
EXTERN size_t _dl_tls_static_size;
|
||
|
||
/* Alignment requirement of the static TLS block. */
|
||
EXTERN size_t _dl_tls_static_align;
|
||
|
||
/* Size of surplus space in the static TLS area for dynamically
|
||
loaded modules with IE-model TLS or for TLSDESC optimization.
|
||
See comments in elf/dl-tls.c where it is initialized. */
|
||
EXTERN size_t _dl_tls_static_surplus;
|
||
|
||
/* 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;
|
||
|
||
/* All search directories defined at startup. This is assigned a
|
||
non-NULL pointer by the ld.so startup code (after initialization
|
||
to NULL), so this can also serve as an indicator whether a copy
|
||
of ld.so is initialized and active. See the rtld_active function
|
||
below. */
|
||
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;
|
||
|
||
# define PROCINFO_DECL
|
||
# ifndef PROCINFO_CLASS
|
||
# define PROCINFO_CLASS EXTERN
|
||
# endif
|
||
# include <dl-vdso-setup.c>
|
||
#endif
|
||
|
||
/* Mask for more hardware capabilities that are available on some
|
||
platforms. */
|
||
EXTERN uint64_t _dl_hwcap2;
|
||
|
||
EXTERN enum dso_sort_algorithm _dl_dso_sort_algo;
|
||
|
||
#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)));
|
||
void (*_dl_mcount) (ElfW(Addr) frompc, ElfW(Addr) selfpc);
|
||
lookup_t (*_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 *);
|
||
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);
|
||
/* libdl in a secondary namespace (after dlopen) must use
|
||
_dl_catch_error from the main namespace, so it has to be
|
||
exported in some way. */
|
||
int (*_dl_catch_error) (const char **objname, const char **errstring,
|
||
bool *mallocedp, void (*operate) (void *),
|
||
void *args);
|
||
/* libdl in a secondary namespace must use free from the base
|
||
namespace. */
|
||
void (*_dl_error_free) (void *);
|
||
void *(*_dl_tls_get_addr_soft) (struct link_map *);
|
||
|
||
/* Called from __libc_shared to deallocate malloc'ed memory. */
|
||
void (*_dl_libc_freeres) (void);
|
||
|
||
/* Implementation of _dl_find_object. The public entry point is in
|
||
libc, and this is patched by __rtld_static_init to support static
|
||
dlopen. */
|
||
int (*_dl_find_object) (void *, struct dl_find_object *);
|
||
|
||
#ifdef HAVE_DL_DISCOVER_OSVERSION
|
||
int (*_dl_discover_osversion) (void);
|
||
#endif
|
||
|
||
/* Dynamic linker operations used after static dlopen. */
|
||
const struct dlfcn_hook *_dl_dlfcn_hook;
|
||
|
||
/* List of auditing interfaces. */
|
||
struct audit_ifaces *_dl_audit;
|
||
unsigned int _dl_naudit;
|
||
};
|
||
# define __rtld_global_attribute__
|
||
# if 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
|
||
|
||
#if PTHREAD_IN_LIBC
|
||
/* This function changes the permissions of all stacks (not just those
|
||
of the main stack). */
|
||
int _dl_make_stacks_executable (void **stack_endp) attribute_hidden;
|
||
#else
|
||
/* This is the initial value of GL(dl_make_stack_executable_hook).
|
||
A threads library can change it. The ld.so implementation changes
|
||
the permissions of the main stack only. */
|
||
extern int _dl_make_stack_executable (void **stack_endp);
|
||
rtld_hidden_proto (_dl_make_stack_executable)
|
||
#endif
|
||
|
||
/* 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
|
||
;
|
||
rtld_hidden_proto (_dl_argv)
|
||
#if 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
|
||
;
|
||
#endif
|
||
#define rtld_progname _dl_argv[0]
|
||
|
||
/* Flag set at startup and cleared when the last initializer has run. */
|
||
extern int _dl_starting_up;
|
||
weak_extern (_dl_starting_up)
|
||
rtld_hidden_proto (_dl_starting_up)
|
||
|
||
/* Random data provided by the kernel. */
|
||
extern void *_dl_random attribute_hidden attribute_relro;
|
||
|
||
/* 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))) attribute_hidden;
|
||
|
||
|
||
/* Write a message on the specified descriptor FD. The parameters are
|
||
interpreted as for a `printf' call. */
|
||
#if IS_IN (rtld) || !defined (SHARED)
|
||
extern void _dl_dprintf (int fd, const char *fmt, ...)
|
||
__attribute__ ((__format__ (__printf__, 2, 3)))
|
||
attribute_hidden;
|
||
#else
|
||
__attribute__ ((always_inline, __format__ (__printf__, 2, 3)))
|
||
static inline void
|
||
_dl_dprintf (int fd, const char *fmt, ...)
|
||
{
|
||
/* Use local declaration to avoid includign <stdio.h>. */
|
||
extern int __dprintf(int fd, const char *format, ...) attribute_hidden;
|
||
__dprintf (fd, fmt, __builtin_va_arg_pack ());
|
||
}
|
||
#endif
|
||
|
||
/* Write LENGTH bytes at BUFFER to FD, like write. Returns the number
|
||
of bytes written on success, or a negative error constant on
|
||
failure. */
|
||
ssize_t _dl_write (int fd, const void *buffer, size_t length)
|
||
attribute_hidden;
|
||
|
||
/* Write a message on the specified descriptor standard output. The
|
||
parameters are interpreted as for a `printf' call. */
|
||
void _dl_printf (const char *fmt, ...)
|
||
attribute_hidden __attribute__ ((__format__ (__printf__, 1, 2)));
|
||
|
||
/* Write a message on the specified descriptor standard error. The
|
||
parameters are interpreted as for a `printf' call. */
|
||
void _dl_error_printf (const char *fmt, ...)
|
||
attribute_hidden __attribute__ ((__format__ (__printf__, 1, 2)));
|
||
|
||
/* Write a message on the specified descriptor standard error and exit
|
||
the program. The parameters are interpreted as for a `printf' call. */
|
||
void _dl_fatal_printf (const char *fmt, ...)
|
||
__attribute__ ((__format__ (__printf__, 1, 2), __noreturn__));
|
||
rtld_hidden_proto (_dl_fatal_printf)
|
||
|
||
/* An exception raised by the _dl_signal_error function family and
|
||
caught by _dl_catch_error function family. Exceptions themselves
|
||
are copied as part of the raise operation, but the strings are
|
||
not. */
|
||
struct dl_exception
|
||
{
|
||
const char *objname;
|
||
const char *errstring;
|
||
|
||
/* This buffer typically stores both objname and errstring
|
||
above. */
|
||
char *message_buffer;
|
||
};
|
||
|
||
/* Creates a new exception. This calls malloc; if allocation fails,
|
||
dummy values are inserted. OBJECT is the name of the problematical
|
||
shared object, or null if its a general problem. ERRSTRING is a
|
||
string describing the specific problem. */
|
||
void _dl_exception_create (struct dl_exception *, const char *object,
|
||
const char *errstring)
|
||
__attribute__ ((nonnull (1, 3)));
|
||
rtld_hidden_proto (_dl_exception_create)
|
||
|
||
/* Used internally to implement dlerror message freeing. See
|
||
include/dlfcn.h and dlfcn/dlerror.c. */
|
||
void _dl_error_free (void *ptr) attribute_hidden;
|
||
|
||
/* Like _dl_exception_create, but create errstring from a format
|
||
string FMT. Currently, only "%s" and "%%" are supported as format
|
||
directives. */
|
||
void _dl_exception_create_format (struct dl_exception *, const char *objname,
|
||
const char *fmt, ...)
|
||
__attribute__ ((nonnull (1, 3), format (printf, 3, 4)));
|
||
rtld_hidden_proto (_dl_exception_create_format)
|
||
|
||
/* Deallocate the exception, freeing allocated buffers (if
|
||
possible). */
|
||
void _dl_exception_free (struct dl_exception *)
|
||
__attribute__ ((nonnull (1)));
|
||
rtld_hidden_proto (_dl_exception_free)
|
||
|
||
/* This function is called by all the internal dynamic linker
|
||
functions when they encounter an error. ERRCODE is either an
|
||
`errno' code or zero; it specifies the return value of
|
||
_dl_catch_error. OCCASION is included in the error message if the
|
||
process is terminated immediately. */
|
||
void _dl_signal_exception (int errcode, struct dl_exception *,
|
||
const char *occasion)
|
||
__attribute__ ((__noreturn__));
|
||
libc_hidden_proto (_dl_signal_exception)
|
||
|
||
/* Like _dl_signal_exception, but creates the exception first. */
|
||
extern void _dl_signal_error (int errcode, const char *object,
|
||
const char *occasion, const char *errstring)
|
||
__attribute__ ((__noreturn__));
|
||
libc_hidden_proto (_dl_signal_error)
|
||
|
||
/* Like _dl_signal_exception, but may return when called in the
|
||
context of _dl_receive_error. This is only used during ld.so
|
||
bootstrap. In static and profiled builds, this is equivalent to
|
||
_dl_signal_exception. */
|
||
#if IS_IN (rtld)
|
||
extern void _dl_signal_cexception (int errcode, struct dl_exception *,
|
||
const char *occasion) attribute_hidden;
|
||
#else
|
||
__attribute__ ((always_inline))
|
||
static inline void
|
||
_dl_signal_cexception (int errcode, struct dl_exception *exception,
|
||
const char *occasion)
|
||
{
|
||
_dl_signal_exception (errcode, exception, occasion);
|
||
}
|
||
#endif
|
||
|
||
/* See _dl_signal_cexception above. */
|
||
#if IS_IN (rtld)
|
||
extern void _dl_signal_cerror (int errcode, const char *object,
|
||
const char *occasion, const char *errstring)
|
||
attribute_hidden;
|
||
#else
|
||
__attribute__ ((always_inline))
|
||
static inline void
|
||
_dl_signal_cerror (int errcode, const char *object,
|
||
const char *occasion, const char *errstring)
|
||
{
|
||
_dl_signal_error (errcode, object, occasion, errstring);
|
||
}
|
||
#endif
|
||
|
||
/* 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) attribute_hidden;
|
||
|
||
/* Call OPERATE, catching errors from `_dl_signal_error' and related
|
||
functions. If there is no error, *ERRSTRING is set to null. If
|
||
there is an error, *ERRSTRING is set to a string constructed from
|
||
the strings passed to _dl_signal_error, and the error code passed
|
||
is the return value and *OBJNAME is set to the object name which
|
||
experienced the problems. ERRSTRING if nonzero points to a
|
||
malloc'ed string which the caller has to free after use. ARGS is
|
||
passed as argument to OPERATE. MALLOCEDP is set to true only if
|
||
the returned string is allocated using the libc's malloc. */
|
||
extern int _dl_catch_error (const char **objname, const char **errstring,
|
||
bool *mallocedp, void (*operate) (void *),
|
||
void *args);
|
||
libc_hidden_proto (_dl_catch_error)
|
||
|
||
/* Used for initializing GLRO (_dl_catch_error). */
|
||
extern __typeof__ (_dl_catch_error) _rtld_catch_error attribute_hidden;
|
||
|
||
/* Call OPERATE (ARGS). If no error occurs, set *EXCEPTION to zero.
|
||
Otherwise, store a copy of the raised exception in *EXCEPTION,
|
||
which has to be freed by _dl_exception_free. As a special case, if
|
||
EXCEPTION is null, call OPERATE (ARGS) with exception handling
|
||
disabled (so that exceptions are fatal). */
|
||
int _dl_catch_exception (struct dl_exception *exception,
|
||
void (*operate) (void *), void *args);
|
||
libc_hidden_proto (_dl_catch_exception)
|
||
|
||
/* 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) 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)
|
||
attribute_hidden;
|
||
|
||
/* Cache the locations of MAP's hash table. */
|
||
extern void _dl_setup_hash (struct link_map *map) 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);
|
||
|
||
/* Process PT_GNU_PROPERTY program header PH in module L after
|
||
PT_LOAD segments are mapped from file FD. */
|
||
void _dl_process_pt_gnu_property (struct link_map *l, int fd,
|
||
const ElfW(Phdr) *ph);
|
||
|
||
|
||
/* 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,
|
||
/* Set if dl_lookup is called for non-lazy relocation processing
|
||
from _dl_relocate_object in elf/dl-reloc.c. */
|
||
DL_LOOKUP_FOR_RELOCATE = 8,
|
||
};
|
||
|
||
/* 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)
|
||
attribute_hidden;
|
||
|
||
|
||
/* Restricted version of _dl_lookup_symbol_x. Searches MAP (and only
|
||
MAP) for the symbol UNDEF_NAME, with GNU hash NEW_HASH (computed
|
||
with dl_new_hash), symbol version VERSION, and symbol version hash
|
||
VERSION_HASH (computed with _dl_elf_hash). Returns a pointer to
|
||
the symbol table entry in MAP on success, or NULL on failure. MAP
|
||
must have symbol versioning information, or otherwise the result is
|
||
undefined. */
|
||
const ElfW(Sym) *_dl_lookup_direct (struct link_map *map,
|
||
const char *undef_name,
|
||
uint32_t new_hash,
|
||
const char *version,
|
||
uint32_t version_hash) attribute_hidden;
|
||
|
||
/* 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)
|
||
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)
|
||
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) 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)
|
||
attribute_hidden __attribute__ ((__noreturn__));
|
||
|
||
/* 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) attribute_hidden;
|
||
|
||
/* 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) attribute_hidden;
|
||
|
||
/* 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) attribute_hidden;
|
||
|
||
/* Call the finalizer functions of all shared objects whose
|
||
initializer functions have completed. */
|
||
extern void _dl_fini (void) attribute_hidden;
|
||
|
||
/* Sort array MAPS according to dependencies of the contained objects. */
|
||
extern void _dl_sort_maps (struct link_map **maps, unsigned int nmaps,
|
||
unsigned int skip, bool for_fini) attribute_hidden;
|
||
|
||
/* 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_extended' for the namespace NS. LDBASE
|
||
is the run-time load address of the dynamic linker, to be put in the
|
||
`r_ldbase' member. Return the address of the structure. */
|
||
extern struct r_debug *_dl_debug_initialize (ElfW(Addr) ldbase, Lmid_t ns)
|
||
attribute_hidden;
|
||
|
||
/* Update the `r_map' member and return the address of `struct r_debug'
|
||
of the namespace NS. */
|
||
extern struct r_debug *_dl_debug_update (Lmid_t ns) attribute_hidden;
|
||
|
||
/* Initialize the basic data structure for the search paths. SOURCE
|
||
is either "LD_LIBRARY_PATH" or "--library-path".
|
||
GLIBC_HWCAPS_PREPEND adds additional glibc-hwcaps subdirectories to
|
||
search. GLIBC_HWCAPS_MASK is used to filter the built-in
|
||
subdirectories if not NULL. */
|
||
extern void _dl_init_paths (const char *library_path, const char *source,
|
||
const char *glibc_hwcaps_prepend,
|
||
const char *glibc_hwcaps_mask)
|
||
attribute_hidden;
|
||
|
||
/* Gather the information needed to install the profiling tables and start
|
||
the timers. */
|
||
extern void _dl_start_profile (void) attribute_hidden;
|
||
|
||
/* The actual functions used to keep book on the calls. */
|
||
extern void _dl_mcount (ElfW(Addr) frompc, ElfW(Addr) selfpc);
|
||
rtld_hidden_proto (_dl_mcount)
|
||
|
||
/* 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) attribute_hidden;
|
||
|
||
/* Return all environment variables starting with `LD_', one after the
|
||
other. */
|
||
extern char *_dl_next_ld_env_entry (char ***position) attribute_hidden;
|
||
|
||
/* Return an array with the names of the important hardware
|
||
capabilities. PREPEND is a colon-separated list of glibc-hwcaps
|
||
directories to search first. MASK is a colon-separated list used
|
||
to filter the built-in glibc-hwcaps subdirectories. The length of
|
||
the array is written to *SZ, and the maximum of all strings length
|
||
is written to *MAX_CAPSTRLEN. */
|
||
const struct r_strlenpair *_dl_important_hwcaps (const char *prepend,
|
||
const char *mask,
|
||
size_t *sz,
|
||
size_t *max_capstrlen)
|
||
attribute_hidden;
|
||
|
||
/* Look up NAME in ld.so.cache and return the file name stored there,
|
||
or null if none is found. Caller must free returned string. */
|
||
extern char *_dl_load_cache_lookup (const char *name) attribute_hidden;
|
||
|
||
/* 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) 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) attribute_hidden;
|
||
|
||
|
||
/* Determine next available module ID and set the L l_tls_modid. */
|
||
extern void _dl_assign_tls_modid (struct link_map *l) attribute_hidden;
|
||
|
||
/* Count the modules with TLS segments. */
|
||
extern size_t _dl_count_modids (void) attribute_hidden;
|
||
|
||
/* Calculate offset of the TLS blocks in the static TLS block. */
|
||
extern void _dl_determine_tlsoffset (void) attribute_hidden;
|
||
|
||
/* Calculate the size of the static TLS surplus, when the given
|
||
number of audit modules are loaded. */
|
||
void _dl_tls_static_surplus_init (size_t naudit) attribute_hidden;
|
||
|
||
/* This function is called very early from dl_main to set up TLS and
|
||
other thread-related data structures. */
|
||
void __tls_pre_init_tp (void) attribute_hidden;
|
||
|
||
/* This function is called after processor-specific initialization of
|
||
the TCB and thread pointer via TLS_INIT_TP, to complete very early
|
||
initialization of the thread library. */
|
||
void __tls_init_tp (void) attribute_hidden;
|
||
|
||
#ifndef SHARED
|
||
/* Set up the TCB for statically linked applications. This is called
|
||
early during startup because we always use TLS (for errno and the
|
||
stack protector, among other things). */
|
||
void __libc_setup_tls (void);
|
||
|
||
# if ENABLE_STATIC_PIE
|
||
/* Relocate static executable with PIE. */
|
||
extern void _dl_relocate_static_pie (void) attribute_hidden;
|
||
|
||
/* Get a pointer to _dl_main_map. */
|
||
extern struct link_map * _dl_get_dl_main_map (void)
|
||
__attribute__ ((visibility ("hidden")));
|
||
# else
|
||
# define _dl_relocate_static_pie()
|
||
# endif
|
||
#endif
|
||
|
||
/* Initialize the DSO sort algorithm to use. */
|
||
#if !HAVE_TUNABLES
|
||
static inline void
|
||
__always_inline
|
||
_dl_sort_maps_init (void)
|
||
{
|
||
/* This is optimized out if tunables are not enabled. */
|
||
}
|
||
#else
|
||
extern void _dl_sort_maps_init (void) attribute_hidden;
|
||
#endif
|
||
|
||
/* Initialization of libpthread for statically linked applications.
|
||
If libpthread is not linked in, this is an empty function. */
|
||
void __pthread_initialize_minimal (void) weak_function;
|
||
|
||
/* Allocate memory for static TLS block (unless MEM is nonzero) and dtv. */
|
||
extern void *_dl_allocate_tls (void *mem);
|
||
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);
|
||
|
||
extern void _dl_allocate_static_tls (struct link_map *map) 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) attribute_hidden;
|
||
extern void *_dl_allocate_tls_init (void *, bool);
|
||
rtld_hidden_proto (_dl_allocate_tls_init)
|
||
|
||
/* Deallocate memory allocated with _dl_allocate_tls. */
|
||
extern void _dl_deallocate_tls (void *tcb, bool dealloc_tcb);
|
||
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) attribute_hidden;
|
||
|
||
/* Substitute DST values. */
|
||
extern char *_dl_dst_substitute (struct link_map *l, const char *name,
|
||
char *result) 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. If DO_ADD is false, only the
|
||
required memory is allocated. Must be called with GL
|
||
(dl_load_tls_lock) acquired. If the function has already been called
|
||
for the link map L with !do_add, then this function will not raise
|
||
an exception, otherwise it is possible that it encounters a memory
|
||
allocation failure. */
|
||
extern void _dl_add_to_slotinfo (struct link_map *l, bool do_add)
|
||
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)
|
||
attribute_hidden;
|
||
|
||
/* 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)
|
||
attribute_hidden;
|
||
|
||
/* Show show of an object. */
|
||
extern void _dl_show_scope (struct link_map *new, int from)
|
||
attribute_hidden;
|
||
|
||
extern struct link_map *_dl_find_dso_for_object (const ElfW(Addr) addr);
|
||
rtld_hidden_proto (_dl_find_dso_for_object)
|
||
|
||
/* Initialization which is normally done by the dynamic linker. */
|
||
extern void _dl_non_dynamic_init (void)
|
||
attribute_hidden;
|
||
|
||
/* Used by static binaries to check the auxiliary vector. */
|
||
extern void _dl_aux_init (ElfW(auxv_t) *av)
|
||
attribute_hidden;
|
||
|
||
/* Initialize the static TLS space for the link map in all existing
|
||
threads. */
|
||
#if PTHREAD_IN_LIBC
|
||
void _dl_init_static_tls (struct link_map *map) attribute_hidden;
|
||
#endif
|
||
static inline void
|
||
dl_init_static_tls (struct link_map *map)
|
||
{
|
||
#if PTHREAD_IN_LIBC
|
||
/* The stack list is available to ld.so, so the initialization can
|
||
be handled within ld.so directly. */
|
||
_dl_init_static_tls (map);
|
||
#else
|
||
GL (dl_init_static_tls) (map);
|
||
#endif
|
||
}
|
||
|
||
#ifndef SHARED
|
||
/* Called before relocating ld.so during static dlopen. This can be
|
||
used to partly initialize the dormant ld.so copy in the static
|
||
dlopen namespace. */
|
||
void __rtld_static_init (struct link_map *map) attribute_hidden;
|
||
#endif
|
||
|
||
/* Return true if the ld.so copy in this namespace is actually active
|
||
and working. If false, the dl_open/dlfcn hooks have to be used to
|
||
call into the outer dynamic linker (which happens after static
|
||
dlopen). */
|
||
#ifdef SHARED
|
||
static inline bool
|
||
rtld_active (void)
|
||
{
|
||
/* The default-initialized variable does not have a non-zero
|
||
dl_init_all_dirs member, so this allows us to recognize an
|
||
initialized and active ld.so copy. */
|
||
return GLRO(dl_init_all_dirs) != NULL;
|
||
}
|
||
|
||
static inline struct auditstate *
|
||
link_map_audit_state (struct link_map *l, size_t index)
|
||
{
|
||
if (l == &GL (dl_rtld_map))
|
||
/* The auditstate array is stored separately. */
|
||
return &GL (dl_rtld_auditstate) [index];
|
||
else
|
||
{
|
||
/* The auditstate array follows the link map in memory. */
|
||
struct auditstate *base = (struct auditstate *) (l + 1);
|
||
return &base[index];
|
||
}
|
||
}
|
||
|
||
/* Call the la_objsearch from the audit modules from the link map L. If
|
||
ORIGNAME is non NULL, it is updated with the revious name prior calling
|
||
la_objsearch. */
|
||
const char *_dl_audit_objsearch (const char *name, struct link_map *l,
|
||
unsigned int code)
|
||
attribute_hidden;
|
||
|
||
/* Call the la_activity from the audit modules from the link map L and issues
|
||
the ACTION argument. */
|
||
void _dl_audit_activity_map (struct link_map *l, int action)
|
||
attribute_hidden;
|
||
|
||
/* Call the la_activity from the audit modules from the link map from the
|
||
namespace NSID and issues the ACTION argument. */
|
||
void _dl_audit_activity_nsid (Lmid_t nsid, int action)
|
||
attribute_hidden;
|
||
|
||
/* Call the la_objopen from the audit modules for the link_map L on the
|
||
namespace identification NSID. */
|
||
void _dl_audit_objopen (struct link_map *l, Lmid_t nsid)
|
||
attribute_hidden;
|
||
|
||
/* Call the la_objclose from the audit modules for the link_map L. */
|
||
void _dl_audit_objclose (struct link_map *l)
|
||
attribute_hidden;
|
||
|
||
/* Call the la_preinit from the audit modules for the link_map L. */
|
||
void _dl_audit_preinit (struct link_map *l);
|
||
|
||
/* Call the la_symbind{32,64} from the audit modules for the link_map L. If
|
||
RELOC_RESULT is NULL it assumes the symbol to be bind-now and will set
|
||
the flags with LA_SYMB_NOPLTENTER | LA_SYMB_NOPLTEXIT prior calling
|
||
la_symbind{32,64}. */
|
||
void _dl_audit_symbind (struct link_map *l, struct reloc_result *reloc_result,
|
||
const ElfW(Sym) *defsym, DL_FIXUP_VALUE_TYPE *value,
|
||
lookup_t result)
|
||
attribute_hidden;
|
||
/* Same as _dl_audit_symbind, but also sets LA_SYMB_DLSYM flag. */
|
||
void _dl_audit_symbind_alt (struct link_map *l, const ElfW(Sym) *ref,
|
||
void **value, lookup_t result);
|
||
rtld_hidden_proto (_dl_audit_symbind_alt)
|
||
void _dl_audit_pltenter (struct link_map *l, struct reloc_result *reloc_result,
|
||
DL_FIXUP_VALUE_TYPE *value, void *regs,
|
||
long int *framesize)
|
||
attribute_hidden;
|
||
void DL_ARCH_FIXUP_ATTRIBUTE _dl_audit_pltexit (struct link_map *l,
|
||
ElfW(Word) reloc_arg,
|
||
const void *inregs,
|
||
void *outregs)
|
||
attribute_hidden;
|
||
#endif /* SHARED */
|
||
|
||
#if PTHREAD_IN_LIBC && defined SHARED
|
||
/* Recursive locking implementation for use within the dynamic loader.
|
||
Used to define the __rtld_lock_lock_recursive and
|
||
__rtld_lock_unlock_recursive via <libc-lock.h>. Initialized to a
|
||
no-op dummy implementation early. Similar
|
||
to GL (dl_rtld_lock_recursive) and GL (dl_rtld_unlock_recursive)
|
||
in !PTHREAD_IN_LIBC builds. */
|
||
extern int (*___rtld_mutex_lock) (pthread_mutex_t *) attribute_hidden;
|
||
extern int (*___rtld_mutex_unlock) (pthread_mutex_t *lock) attribute_hidden;
|
||
|
||
/* Called after libc has been loaded, but before RELRO is activated.
|
||
Used to initialize the function pointers to the actual
|
||
implementations. */
|
||
void __rtld_mutex_init (void) attribute_hidden;
|
||
#else /* !PTHREAD_IN_LIBC */
|
||
static inline void
|
||
__rtld_mutex_init (void)
|
||
{
|
||
/* The initialization happens later (!PTHREAD_IN_LIBC) or is not
|
||
needed at all (!SHARED). */
|
||
}
|
||
#endif /* !PTHREAD_IN_LIBC */
|
||
|
||
/* Implementation of GL (dl_libc_freeres). */
|
||
void __rtld_libc_freeres (void) attribute_hidden;
|
||
|
||
void __thread_gscope_wait (void) attribute_hidden;
|
||
# define THREAD_GSCOPE_WAIT() __thread_gscope_wait ()
|
||
|
||
__END_DECLS
|
||
|
||
#endif /* ldsodefs.h */
|