/* Support for dynamic linking code in static libc.
- Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
+ Copyright (C) 1996-2015 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.
+ 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.
+ 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., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, 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/>. */
/* This file defines some things that for the dynamic linker are defined in
rtld.c and dl-sysdep.c in ways appropriate to bootstrap dynamic linking. */
#include <errno.h>
+#include <libintl.h>
#include <stdlib.h>
#include <unistd.h>
-#include <elf/ldsodefs.h>
+#include <sys/param.h>
+#include <stdint.h>
+#include <ldsodefs.h>
#include <dl-machine.h>
+#include <bits/libc-lock.h>
+#include <dl-cache.h>
+#include <dl-librecon.h>
+#include <dl-procinfo.h>
+#include <unsecvars.h>
+#include <hp-timing.h>
+#include <stackinfo.h>
extern char *__progname;
char **_dl_argv = &__progname; /* This is checked for some error messages. */
const char *_dl_platform;
size_t _dl_platformlen;
-int _dl_debug_libs;
-int _dl_debug_impcalls;
-int _dl_debug_bindings;
-int _dl_debug_symbols;
-int _dl_debug_versions;
-int _dl_debug_reloc;
-int _dl_debug_files;
+int _dl_debug_mask;
+int _dl_lazy;
+ElfW(Addr) _dl_use_load_bias = -2;
+int _dl_dynamic_weak;
/* If nonzero print warnings about problematic situations. */
int _dl_verbose;
-/* Structure to store information about search paths. */
-struct r_search_path *_dl_search_paths;
-
/* We never do profiling. */
const char *_dl_profile;
+const char *_dl_profile_output;
-/* Names of shared object for which the RPATHs should be ignored. */
+/* Names of shared object for which the RUNPATHs and RPATHs should be
+ ignored. */
const char *_dl_inhibit_rpath;
/* The map for the object we will profile. */
/* Path where the binary is found. */
const char *_dl_origin_path;
-/* Initially empty list of loaded objects. */
-struct link_map *_dl_loaded;
+/* Nonzero if runtime lookup should not update the .got/.plt. */
+int _dl_bind_not;
+
+/* A dummy link map for the executable, used by dlopen to access the global
+ scope. We don't export any symbols ourselves, so this can be minimal. */
+static struct link_map _dl_main_map =
+ {
+ .l_name = (char *) "",
+ .l_real = &_dl_main_map,
+ .l_ns = LM_ID_BASE,
+ .l_libname = &(struct libname_list) { .name = "", .dont_free = 1 },
+ .l_searchlist =
+ {
+ .r_list = &(struct link_map *) { &_dl_main_map },
+ .r_nlist = 1,
+ },
+ .l_symbolic_searchlist = { .r_list = &(struct link_map *) { NULL } },
+ .l_type = lt_executable,
+ .l_scope_mem = { &_dl_main_map.l_searchlist },
+ .l_scope_max = (sizeof (_dl_main_map.l_scope_mem)
+ / sizeof (_dl_main_map.l_scope_mem[0])),
+ .l_scope = _dl_main_map.l_scope_mem,
+ .l_local_scope = { &_dl_main_map.l_searchlist },
+ .l_used = 1,
+ .l_flags_1 = DF_1_NODEFLIB,
+ .l_tls_offset = NO_TLS_OFFSET,
+ .l_serial = 1,
+ };
+
+/* Namespace information. */
+struct link_namespaces _dl_ns[DL_NNS] =
+ {
+ [LM_ID_BASE] =
+ {
+ ._ns_loaded = &_dl_main_map,
+ ._ns_nloaded = 1,
+ ._ns_main_searchlist = &_dl_main_map.l_searchlist,
+ }
+ };
+size_t _dl_nns = 1;
+
+/* Incremented whenever something may have been added to dl_loaded. */
+unsigned long long _dl_load_adds = 1;
+
+/* Fake scope of the main application. */
+struct r_scope_elem _dl_initial_searchlist =
+ {
+ .r_list = &(struct link_map *) { &_dl_main_map },
+ .r_nlist = 1,
+ };
+
+#ifndef HAVE_INLINED_SYSCALLS
+/* Nonzero during startup. */
+int _dl_starting_up = 1;
+#endif
+
+/* Random data provided by the kernel. */
+void *_dl_random;
+
+/* Get architecture specific initializer. */
+#include <dl-procinfo.c>
+
+/* Initial value of the CPU clock. */
+#ifndef HP_TIMING_NONAVAIL
+hp_timing_t _dl_cpuclock_offset;
+#endif
+
+void (*_dl_init_static_tls) (struct link_map *) = &_dl_nothread_init_static_tls;
+
+size_t _dl_pagesize = EXEC_PAGESIZE;
+
+int _dl_inhibit_cache;
+
+unsigned int _dl_osversion;
+
+/* All known directories in sorted order. */
+struct r_search_path_elem *_dl_all_dirs;
+
+/* All directories after startup. */
+struct r_search_path_elem *_dl_init_all_dirs;
+
+/* The object to be initialized first. */
+struct link_map *_dl_initfirst;
+
+/* Descriptor to write debug messages to. */
+int _dl_debug_fd = STDERR_FILENO;
+
+int _dl_correct_cache_id = _DL_CACHE_DEFAULT_ID;
+
+ElfW(auxv_t) *_dl_auxv;
+const ElfW(Phdr) *_dl_phdr;
+size_t _dl_phnum;
+uint64_t _dl_hwcap __attribute__ ((nocommon));
+uint64_t _dl_hwcap2 __attribute__ ((nocommon));
+
+/* The value of the FPU control word the kernel will preset in hardware. */
+fpu_control_t _dl_fpu_control = _FPU_DEFAULT;
+
+/* This is not initialized to HWCAP_IMPORTANT, matching the definition
+ of _dl_important_hwcaps, below, where no hwcap strings are ever
+ used. This mask is still used to mediate the lookups in the cache
+ file. Since there is no way to set this nonzero (we don't grok the
+ LD_HWCAP_MASK environment variable here), there is no real point in
+ setting _dl_hwcap nonzero below, but we do anyway. */
+uint64_t _dl_hwcap_mask __attribute__ ((nocommon));
+
+/* Prevailing state of the stack. Generally this includes PF_X, indicating it's
+ * executable but this isn't true for all platforms. */
+ElfW(Word) _dl_stack_flags = DEFAULT_STACK_PERMS;
+
+/* 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. */
+int (*_dl_make_stack_executable_hook) (void **) internal_function
+ = _dl_make_stack_executable;
+
+
+/* Function in libpthread to wait for termination of lookups. */
+void (*_dl_wait_lookup_done) (void);
+
+struct dl_scope_free_list *_dl_scope_free_list;
+
+#ifdef NEED_DL_SYSINFO
+/* Needed for improved syscall handling on at least x86/Linux. */
+uintptr_t _dl_sysinfo = DL_SYSINFO_DEFAULT;
+#endif
+#ifdef NEED_DL_SYSINFO_DSO
+/* Address of the ELF headers in the vsyscall page. */
+const ElfW(Ehdr) *_dl_sysinfo_dso;
+
+struct link_map *_dl_sysinfo_map;
+
+# include "get-dynamic-info.h"
+#endif
+#include "setup-vdso.h"
-/* Fake scope. In dynamically linked binaries this is the scope of the
- main application but here we don't have something like this. So
- create a fake scope containing nothing. */
-static struct r_scope_elem fake_scope;
-/* Variable which can be used in lookup to process the global scope. */
-struct r_scope_elem *_dl_global_scope[2] = { &fake_scope, NULL };
-/* This is a global pointer to this structure which is public. It is
- used by dlopen/dlclose to add and remove objects from what is regarded
- to be the global scope. */
-struct r_scope_elem *_dl_main_searchlist = &fake_scope;
+/* 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_initialized_recursive (, _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_initialized_recursive (, _dl_load_write_lock)
-static void non_dynamic_init (void) __attribute__ ((unused));
-static void
-non_dynamic_init (void)
+#ifdef HAVE_AUX_VECTOR
+int _dl_clktck;
+
+void
+internal_function
+_dl_aux_init (ElfW(auxv_t) *av)
+{
+ int seen = 0;
+ uid_t uid = 0;
+ gid_t gid = 0;
+
+ _dl_auxv = av;
+ for (; av->a_type != AT_NULL; ++av)
+ switch (av->a_type)
+ {
+ case AT_PAGESZ:
+ if (av->a_un.a_val != 0)
+ GLRO(dl_pagesize) = av->a_un.a_val;
+ break;
+ case AT_CLKTCK:
+ GLRO(dl_clktck) = av->a_un.a_val;
+ break;
+ case AT_PHDR:
+ GL(dl_phdr) = (const void *) av->a_un.a_val;
+ break;
+ case AT_PHNUM:
+ GL(dl_phnum) = av->a_un.a_val;
+ break;
+ case AT_HWCAP:
+ GLRO(dl_hwcap) = (unsigned long int) av->a_un.a_val;
+ break;
+ case AT_HWCAP2:
+ GLRO(dl_hwcap2) = (unsigned long int) av->a_un.a_val;
+ break;
+ case AT_FPUCW:
+ GLRO(dl_fpu_control) = av->a_un.a_val;
+ break;
+#ifdef NEED_DL_SYSINFO
+ case AT_SYSINFO:
+ GL(dl_sysinfo) = av->a_un.a_val;
+ break;
+#endif
+#ifdef NEED_DL_SYSINFO_DSO
+ case AT_SYSINFO_EHDR:
+ GL(dl_sysinfo_dso) = (void *) av->a_un.a_val;
+ break;
+#endif
+ case AT_UID:
+ uid ^= av->a_un.a_val;
+ seen |= 1;
+ break;
+ case AT_EUID:
+ uid ^= av->a_un.a_val;
+ seen |= 2;
+ break;
+ case AT_GID:
+ gid ^= av->a_un.a_val;
+ seen |= 4;
+ break;
+ case AT_EGID:
+ gid ^= av->a_un.a_val;
+ seen |= 8;
+ break;
+ case AT_SECURE:
+ seen = -1;
+ __libc_enable_secure = av->a_un.a_val;
+ __libc_enable_secure_decided = 1;
+ break;
+ case AT_RANDOM:
+ _dl_random = (void *) av->a_un.a_val;
+ break;
+# ifdef DL_PLATFORM_AUXV
+ DL_PLATFORM_AUXV
+# endif
+ }
+ if (seen == 0xf)
+ {
+ __libc_enable_secure = uid != 0 || gid != 0;
+ __libc_enable_secure_decided = 1;
+ }
+}
+#endif
+
+
+void
+internal_function
+_dl_non_dynamic_init (void)
{
+ _dl_main_map.l_origin = _dl_get_origin ();
+ _dl_main_map.l_phdr = GL(dl_phdr);
+ _dl_main_map.l_phnum = GL(dl_phnum);
+
+ if (HP_SMALL_TIMING_AVAIL)
+ HP_TIMING_NOW (_dl_cpuclock_offset);
+
_dl_verbose = *(getenv ("LD_WARN") ?: "") == '\0' ? 0 : 1;
- _dl_pagesize = __getpagesize ();
+ /* Set up the data structures for the system-supplied DSO early,
+ so they can influence _dl_init_paths. */
+ setup_vdso (NULL, NULL);
/* Initialize the data structures for the search paths for shared
objects. */
_dl_init_paths (getenv ("LD_LIBRARY_PATH"));
+ /* Remember the last search directory added at startup. */
+ _dl_init_all_dirs = GL(dl_all_dirs);
+
+ _dl_lazy = *(getenv ("LD_BIND_NOW") ?: "") == '\0';
+
+ _dl_bind_not = *(getenv ("LD_BIND_NOT") ?: "") != '\0';
+
+ _dl_dynamic_weak = *(getenv ("LD_DYNAMIC_WEAK") ?: "") == '\0';
+
+ _dl_profile_output = getenv ("LD_PROFILE_OUTPUT");
+ if (_dl_profile_output == NULL || _dl_profile_output[0] == '\0')
+ _dl_profile_output
+ = &"/var/tmp\0/var/profile"[__libc_enable_secure ? 9 : 0];
+
+ if (__libc_enable_secure)
+ {
+ static const char unsecure_envvars[] =
+ UNSECURE_ENVVARS
+#ifdef EXTRA_UNSECURE_ENVVARS
+ EXTRA_UNSECURE_ENVVARS
+#endif
+ ;
+ const char *cp = unsecure_envvars;
+
+ while (cp < unsecure_envvars + sizeof (unsecure_envvars))
+ {
+ __unsetenv (cp);
+ cp = (const char *) __rawmemchr (cp, '\0') + 1;
+ }
+
+ if (__access ("/etc/suid-debug", F_OK) != 0)
+ __unsetenv ("MALLOC_CHECK_");
+ }
+
#ifdef DL_PLATFORM_INIT
DL_PLATFORM_INIT;
#endif
+#ifdef DL_OSVERSION_INIT
+ DL_OSVERSION_INIT;
+#endif
+
/* Now determine the length of the platform string. */
if (_dl_platform != NULL)
_dl_platformlen = strlen (_dl_platform);
-}
-text_set_element (__libc_subinit, non_dynamic_init);
-
-const struct r_strlenpair *
-internal_function
-_dl_important_hwcaps (const char *platform, size_t platform_len, size_t *sz,
- size_t *max_capstrlen)
-{
- struct r_strlenpair *result;
- /* XXX We don't try to find the capabilities in this case. */
- result = (struct r_strlenpair *) malloc (sizeof (*result));
- if (result == NULL)
- _dl_signal_error (ENOMEM, NULL, "cannot create capability list");
-
- result[0].str = (char *) result; /* Does not really matter. */
- result[0].len = 0;
-
- *sz = 1;
- return result;
+ /* Scan for a program header telling us the stack is nonexecutable. */
+ if (_dl_phdr != NULL)
+ for (uint_fast16_t i = 0; i < _dl_phnum; ++i)
+ if (_dl_phdr[i].p_type == PT_GNU_STACK)
+ {
+ _dl_stack_flags = _dl_phdr[i].p_flags;
+ break;
+ }
}
+
+#ifdef DL_SYSINFO_IMPLEMENTATION
+DL_SYSINFO_IMPLEMENTATION
+#endif
projects / platform / upstream / glibc.git / blobdiff