1400 lines
40 KiB
C
1400 lines
40 KiB
C
/* Map in a shared object's segments from the file.
|
||
Copyright (C) 1995, 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
|
||
This file is part of the GNU C Library.
|
||
|
||
The GNU C Library is free software; you can redistribute it and/or
|
||
modify it under the terms of the GNU Library General Public License as
|
||
published by the Free Software Foundation; either version 2 of the
|
||
License, or (at your option) any later version.
|
||
|
||
The GNU C Library is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||
Library General Public License for more details.
|
||
|
||
You should have received a copy of the GNU Library General Public
|
||
License along with the GNU C Library; see the file COPYING.LIB. If not,
|
||
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
||
Boston, MA 02111-1307, USA. */
|
||
|
||
#include <elf.h>
|
||
#include <errno.h>
|
||
#include <fcntl.h>
|
||
#include <stdlib.h>
|
||
#include <string.h>
|
||
#include <unistd.h>
|
||
#include <elf/ldsodefs.h>
|
||
#include <sys/mman.h>
|
||
#include <sys/param.h>
|
||
#include <sys/stat.h>
|
||
#include <sys/types.h>
|
||
#include "dynamic-link.h"
|
||
#include <stdio-common/_itoa.h>
|
||
|
||
#include <dl-dst.h>
|
||
|
||
/* On some systems, no flag bits are given to specify file mapping. */
|
||
#ifndef MAP_FILE
|
||
#define MAP_FILE 0
|
||
#endif
|
||
|
||
/* The right way to map in the shared library files is MAP_COPY, which
|
||
makes a virtual copy of the data at the time of the mmap call; this
|
||
guarantees the mapped pages will be consistent even if the file is
|
||
overwritten. Some losing VM systems like Linux's lack MAP_COPY. All we
|
||
get is MAP_PRIVATE, which copies each page when it is modified; this
|
||
means if the file is overwritten, we may at some point get some pages
|
||
from the new version after starting with pages from the old version. */
|
||
#ifndef MAP_COPY
|
||
#define MAP_COPY MAP_PRIVATE
|
||
#endif
|
||
|
||
/* Some systems link their relocatable objects for another base address
|
||
than 0. We want to know the base address for these such that we can
|
||
subtract this address from the segment addresses during mapping.
|
||
This results in a more efficient address space usage. Defaults to
|
||
zero for almost all systems. */
|
||
#ifndef MAP_BASE_ADDR
|
||
#define MAP_BASE_ADDR(l) 0
|
||
#endif
|
||
|
||
|
||
#include <endian.h>
|
||
#if BYTE_ORDER == BIG_ENDIAN
|
||
#define byteorder ELFDATA2MSB
|
||
#define byteorder_name "big-endian"
|
||
#elif BYTE_ORDER == LITTLE_ENDIAN
|
||
#define byteorder ELFDATA2LSB
|
||
#define byteorder_name "little-endian"
|
||
#else
|
||
#error "Unknown BYTE_ORDER " BYTE_ORDER
|
||
#define byteorder ELFDATANONE
|
||
#endif
|
||
|
||
#define STRING(x) __STRING (x)
|
||
|
||
#ifdef MAP_ANON
|
||
/* The fd is not examined when using MAP_ANON. */
|
||
#define ANONFD -1
|
||
#else
|
||
int _dl_zerofd = -1;
|
||
#define ANONFD _dl_zerofd
|
||
#endif
|
||
|
||
/* Handle situations where we have a preferred location in memory for
|
||
the shared objects. */
|
||
#ifdef ELF_PREFERRED_ADDRESS_DATA
|
||
ELF_PREFERRED_ADDRESS_DATA;
|
||
#endif
|
||
#ifndef ELF_PREFERRED_ADDRESS
|
||
#define ELF_PREFERRED_ADDRESS(loader, maplength, mapstartpref) (mapstartpref)
|
||
#endif
|
||
#ifndef ELF_FIXED_ADDRESS
|
||
#define ELF_FIXED_ADDRESS(loader, mapstart) ((void) 0)
|
||
#endif
|
||
|
||
size_t _dl_pagesize;
|
||
|
||
extern const char *_dl_platform;
|
||
extern size_t _dl_platformlen;
|
||
|
||
/* This is the decomposed LD_LIBRARY_PATH search path. */
|
||
static struct r_search_path_elem **env_path_list;
|
||
|
||
/* List of the hardware capabilities we might end up using. */
|
||
static const struct r_strlenpair *capstr;
|
||
static size_t ncapstr;
|
||
static size_t max_capstrlen;
|
||
|
||
const unsigned char _dl_pf_to_prot[8] =
|
||
{
|
||
[0] = PROT_NONE,
|
||
[PF_R] = PROT_READ,
|
||
[PF_W] = PROT_WRITE,
|
||
[PF_R | PF_W] = PROT_READ | PROT_WRITE,
|
||
[PF_X] = PROT_EXEC,
|
||
[PF_R | PF_X] = PROT_READ | PROT_EXEC,
|
||
[PF_W | PF_X] = PROT_WRITE | PROT_EXEC,
|
||
[PF_R | PF_W | PF_X] = PROT_READ | PROT_WRITE | PROT_EXEC
|
||
};
|
||
|
||
|
||
/* Get the generated information about the trusted directories. */
|
||
#include "trusted-dirs.h"
|
||
|
||
static const char system_dirs[] = SYSTEM_DIRS;
|
||
static const size_t system_dirs_len[] =
|
||
{
|
||
SYSTEM_DIRS_LEN
|
||
};
|
||
|
||
/* This function has no public prototype. */
|
||
extern ssize_t __libc_read (int, void *, size_t);
|
||
|
||
|
||
/* Local version of `strdup' function. */
|
||
static inline char *
|
||
local_strdup (const char *s)
|
||
{
|
||
size_t len = strlen (s) + 1;
|
||
void *new = malloc (len);
|
||
|
||
if (new == NULL)
|
||
return NULL;
|
||
|
||
return (char *) memcpy (new, s, len);
|
||
}
|
||
|
||
|
||
size_t
|
||
_dl_dst_count (const char *name, int is_path)
|
||
{
|
||
size_t cnt = 0;
|
||
|
||
do
|
||
{
|
||
size_t len = 1;
|
||
|
||
/* $ORIGIN is not expanded for SUID/GUID programs. */
|
||
if ((((!__libc_enable_secure
|
||
&& strncmp (&name[1], "ORIGIN", 6) == 0 && (len = 7) != 0)
|
||
|| (strncmp (&name[1], "PLATFORM", 8) == 0 && (len = 9) != 0))
|
||
&& (name[len] == '\0' || name[len] == '/'
|
||
|| (is_path && name[len] == ':')))
|
||
|| (name[1] == '{'
|
||
&& ((!__libc_enable_secure
|
||
&& strncmp (&name[2], "ORIGIN}", 7) == 0 && (len = 9) != 0)
|
||
|| (strncmp (&name[2], "PLATFORM}", 9) == 0
|
||
&& (len = 11) != 0))))
|
||
++cnt;
|
||
|
||
name = strchr (name + len, '$');
|
||
}
|
||
while (name != NULL);
|
||
|
||
return cnt;
|
||
}
|
||
|
||
|
||
char *
|
||
_dl_dst_substitute (struct link_map *l, const char *name, char *result,
|
||
int is_path)
|
||
{
|
||
char *last_elem, *wp;
|
||
|
||
/* Now fill the result path. While copying over the string we keep
|
||
track of the start of the last path element. When we come accross
|
||
a DST we copy over the value or (if the value is not available)
|
||
leave the entire path element out. */
|
||
last_elem = wp = result;
|
||
|
||
do
|
||
{
|
||
if (*name == '$')
|
||
{
|
||
const char *repl;
|
||
size_t len;
|
||
|
||
if ((((strncmp (&name[1], "ORIGIN", 6) == 0 && (len = 7) != 0)
|
||
|| (strncmp (&name[1], "PLATFORM", 8) == 0 && (len = 9) != 0))
|
||
&& (name[len] == '\0' || name[len] == '/'
|
||
|| (is_path && name[len] == ':')))
|
||
|| (name[1] == '{'
|
||
&& ((strncmp (&name[2], "ORIGIN}", 7) == 0 && (len = 9) != 0)
|
||
|| (strncmp (&name[2], "PLATFORM}", 9) == 0
|
||
&& (len = 11) != 0))))
|
||
{
|
||
repl = ((len == 7 || name[2] == 'O')
|
||
? (__libc_enable_secure ? NULL : l->l_origin)
|
||
: _dl_platform);
|
||
|
||
if (repl != NULL && repl != (const char *) -1)
|
||
{
|
||
wp = __stpcpy (wp, repl);
|
||
name += len;
|
||
}
|
||
else
|
||
{
|
||
/* We cannot use this path element, the value of the
|
||
replacement is unknown. */
|
||
wp = last_elem;
|
||
name += len;
|
||
while (*name != '\0' && (!is_path || *name != ':'))
|
||
++name;
|
||
}
|
||
}
|
||
else
|
||
/* No DST we recognize. */
|
||
*wp++ = *name++;
|
||
}
|
||
else if (is_path && *name == ':')
|
||
{
|
||
*wp++ = *name++;
|
||
last_elem = wp;
|
||
}
|
||
else
|
||
*wp++ = *name++;
|
||
}
|
||
while (*name != '\0');
|
||
|
||
*wp = '\0';
|
||
|
||
return result;
|
||
}
|
||
|
||
|
||
/* Return copy of argument with all recognized dynamic string tokens
|
||
($ORIGIN and $PLATFORM for now) replaced. On some platforms it
|
||
might not be possible to determine the path from which the object
|
||
belonging to the map is loaded. In this case the path element
|
||
containing $ORIGIN is left out. */
|
||
static char *
|
||
expand_dynamic_string_token (struct link_map *l, const char *s)
|
||
{
|
||
/* We make two runs over the string. First we determine how large the
|
||
resulting string is and then we copy it over. Since this is now
|
||
frequently executed operation we are looking here not for performance
|
||
but rather for code size. */
|
||
size_t cnt;
|
||
size_t total;
|
||
char *result;
|
||
|
||
/* Determine the nubmer of DST elements. */
|
||
cnt = DL_DST_COUNT (s, 1);
|
||
|
||
/* If we do not have to replace anything simply copy the string. */
|
||
if (cnt == 0)
|
||
return local_strdup (s);
|
||
|
||
/* Determine the length of the substituted string. */
|
||
total = DL_DST_REQUIRED (l, s, strlen (s), cnt);
|
||
|
||
/* Allocate the necessary memory. */
|
||
result = (char *) malloc (total + 1);
|
||
if (result == NULL)
|
||
return NULL;
|
||
|
||
return DL_DST_SUBSTITUTE (l, s, result, 1);
|
||
}
|
||
|
||
|
||
/* Add `name' to the list of names for a particular shared object.
|
||
`name' is expected to have been allocated with malloc and will
|
||
be freed if the shared object already has this name.
|
||
Returns false if the object already had this name. */
|
||
static void
|
||
internal_function
|
||
add_name_to_object (struct link_map *l, const char *name)
|
||
{
|
||
struct libname_list *lnp, *lastp;
|
||
struct libname_list *newname;
|
||
size_t name_len;
|
||
|
||
lastp = NULL;
|
||
for (lnp = l->l_libname; lnp != NULL; lastp = lnp, lnp = lnp->next)
|
||
if (strcmp (name, lnp->name) == 0)
|
||
return;
|
||
|
||
name_len = strlen (name) + 1;
|
||
newname = malloc (sizeof *newname + name_len);
|
||
if (newname == NULL)
|
||
{
|
||
/* No more memory. */
|
||
_dl_signal_error (ENOMEM, name, "cannot allocate name record");
|
||
return;
|
||
}
|
||
/* The object should have a libname set from _dl_new_object. */
|
||
assert (lastp != NULL);
|
||
|
||
newname->name = memcpy (newname + 1, name, name_len);
|
||
newname->next = NULL;
|
||
lastp->next = newname;
|
||
}
|
||
|
||
/* All known directories in sorted order. */
|
||
static struct r_search_path_elem *all_dirs;
|
||
|
||
/* Standard search directories. */
|
||
static struct r_search_path_elem **rtld_search_dirs;
|
||
|
||
static size_t max_dirnamelen;
|
||
|
||
static inline struct r_search_path_elem **
|
||
fillin_rpath (char *rpath, struct r_search_path_elem **result, const char *sep,
|
||
int check_trusted, const char *what, const char *where)
|
||
{
|
||
char *cp;
|
||
size_t nelems = 0;
|
||
|
||
while ((cp = __strsep (&rpath, sep)) != NULL)
|
||
{
|
||
struct r_search_path_elem *dirp;
|
||
size_t len = strlen (cp);
|
||
|
||
/* `strsep' can pass an empty string. This has to be
|
||
interpreted as `use the current directory'. */
|
||
if (len == 0)
|
||
{
|
||
static const char curwd[] = "./";
|
||
cp = (char *) curwd;
|
||
}
|
||
|
||
/* Remove trailing slashes (except for "/"). */
|
||
while (len > 1 && cp[len - 1] == '/')
|
||
--len;
|
||
|
||
/* Now add one if there is none so far. */
|
||
if (len > 0 && cp[len - 1] != '/')
|
||
cp[len++] = '/';
|
||
|
||
/* Make sure we don't use untrusted directories if we run SUID. */
|
||
if (check_trusted)
|
||
{
|
||
const char *trun = system_dirs;
|
||
size_t idx;
|
||
|
||
/* All trusted directories must be complete names. */
|
||
if (cp[0] != '/')
|
||
continue;
|
||
|
||
for (idx = 0;
|
||
idx < sizeof (system_dirs_len) / sizeof (system_dirs_len[0]);
|
||
++idx)
|
||
{
|
||
if (len == system_dirs_len[idx] && memcmp (trun, cp, len) == 0)
|
||
/* Found it. */
|
||
break;
|
||
|
||
trun += system_dirs_len[idx] + 1;
|
||
}
|
||
|
||
if (idx == sizeof (system_dirs_len) / sizeof (system_dirs_len[0]))
|
||
/* It's no trusted directory, skip it. */
|
||
continue;
|
||
}
|
||
|
||
/* See if this directory is already known. */
|
||
for (dirp = all_dirs; dirp != NULL; dirp = dirp->next)
|
||
if (dirp->dirnamelen == len && memcmp (cp, dirp->dirname, len) == 0)
|
||
break;
|
||
|
||
if (dirp != NULL)
|
||
{
|
||
/* It is available, see whether it's on our own list. */
|
||
size_t cnt;
|
||
for (cnt = 0; cnt < nelems; ++cnt)
|
||
if (result[cnt] == dirp)
|
||
break;
|
||
|
||
if (cnt == nelems)
|
||
result[nelems++] = dirp;
|
||
}
|
||
else
|
||
{
|
||
size_t cnt;
|
||
|
||
/* It's a new directory. Create an entry and add it. */
|
||
dirp = (struct r_search_path_elem *)
|
||
malloc (sizeof (*dirp) + ncapstr * sizeof (enum r_dir_status));
|
||
if (dirp == NULL)
|
||
_dl_signal_error (ENOMEM, NULL,
|
||
"cannot create cache for search path");
|
||
|
||
dirp->dirname = cp;
|
||
dirp->dirnamelen = len;
|
||
|
||
if (len > max_dirnamelen)
|
||
max_dirnamelen = len;
|
||
|
||
/* We have to make sure all the relative directories are never
|
||
ignored. The current directory might change and all our
|
||
saved information would be void. */
|
||
if (cp[0] != '/')
|
||
for (cnt = 0; cnt < ncapstr; ++cnt)
|
||
dirp->status[cnt] = existing;
|
||
else
|
||
for (cnt = 0; cnt < ncapstr; ++cnt)
|
||
dirp->status[cnt] = unknown;
|
||
|
||
dirp->what = what;
|
||
dirp->where = where;
|
||
|
||
dirp->next = all_dirs;
|
||
all_dirs = dirp;
|
||
|
||
/* Put it in the result array. */
|
||
result[nelems++] = dirp;
|
||
}
|
||
}
|
||
|
||
/* Terminate the array. */
|
||
result[nelems] = NULL;
|
||
|
||
return result;
|
||
}
|
||
|
||
|
||
static struct r_search_path_elem **
|
||
internal_function
|
||
decompose_rpath (const char *rpath, struct link_map *l)
|
||
{
|
||
/* Make a copy we can work with. */
|
||
const char *where = l->l_name;
|
||
char *copy;
|
||
char *cp;
|
||
struct r_search_path_elem **result;
|
||
size_t nelems;
|
||
|
||
/* First see whether we must forget the RPATH from this object. */
|
||
if (_dl_inhibit_rpath != NULL && !__libc_enable_secure)
|
||
{
|
||
const char *found = strstr (_dl_inhibit_rpath, where);
|
||
if (found != NULL)
|
||
{
|
||
size_t len = strlen (where);
|
||
if ((found == _dl_inhibit_rpath || found[-1] == ':')
|
||
&& (found[len] == '\0' || found[len] == ':'))
|
||
{
|
||
/* This object is on the list of objects for which the RPATH
|
||
must not be used. */
|
||
result = (struct r_search_path_elem **)
|
||
malloc (sizeof (*result));
|
||
if (result == NULL)
|
||
_dl_signal_error (ENOMEM, NULL,
|
||
"cannot create cache for search path");
|
||
result[0] = NULL;
|
||
|
||
return result;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Make a writable copy. At the same time expand possible dynamic
|
||
string tokens. */
|
||
copy = expand_dynamic_string_token (l, rpath);
|
||
if (copy == NULL)
|
||
_dl_signal_error (ENOMEM, NULL, "cannot create RPATH copy");
|
||
|
||
/* Count the number of necessary elements in the result array. */
|
||
nelems = 0;
|
||
for (cp = copy; *cp != '\0'; ++cp)
|
||
if (*cp == ':')
|
||
++nelems;
|
||
|
||
/* Allocate room for the result. NELEMS + 1 is an upper limit for the
|
||
number of necessary entries. */
|
||
result = (struct r_search_path_elem **) malloc ((nelems + 1 + 1)
|
||
* sizeof (*result));
|
||
if (result == NULL)
|
||
_dl_signal_error (ENOMEM, NULL, "cannot create cache for search path");
|
||
|
||
return fillin_rpath (copy, result, ":", 0, "RPATH", where);
|
||
}
|
||
|
||
|
||
void
|
||
internal_function
|
||
_dl_init_paths (const char *llp)
|
||
{
|
||
size_t idx;
|
||
const char *strp;
|
||
struct r_search_path_elem *pelem, **aelem;
|
||
size_t round_size;
|
||
#ifdef PIC
|
||
struct link_map *l;
|
||
#endif
|
||
|
||
/* Fill in the information about the application's RPATH and the
|
||
directories addressed by the LD_LIBRARY_PATH environment variable. */
|
||
|
||
/* Get the capabilities. */
|
||
capstr = _dl_important_hwcaps (_dl_platform, _dl_platformlen,
|
||
&ncapstr, &max_capstrlen);
|
||
|
||
/* First set up the rest of the default search directory entries. */
|
||
aelem = rtld_search_dirs = (struct r_search_path_elem **)
|
||
malloc ((sizeof (system_dirs_len) / sizeof (system_dirs_len[0]) + 1)
|
||
* sizeof (struct r_search_path_elem *));
|
||
if (rtld_search_dirs == NULL)
|
||
_dl_signal_error (ENOMEM, NULL, "cannot create search path array");
|
||
|
||
round_size = ((2 * sizeof (struct r_search_path_elem) - 1
|
||
+ ncapstr * sizeof (enum r_dir_status))
|
||
/ sizeof (struct r_search_path_elem));
|
||
|
||
rtld_search_dirs[0] = (struct r_search_path_elem *)
|
||
malloc ((sizeof (system_dirs) / sizeof (system_dirs[0]) - 1)
|
||
* round_size * sizeof (struct r_search_path_elem));
|
||
if (rtld_search_dirs[0] == NULL)
|
||
_dl_signal_error (ENOMEM, NULL, "cannot create cache for search path");
|
||
|
||
pelem = all_dirs = rtld_search_dirs[0];
|
||
strp = system_dirs;
|
||
idx = 0;
|
||
|
||
do
|
||
{
|
||
size_t cnt;
|
||
|
||
*aelem++ = pelem;
|
||
|
||
pelem->what = "system search path";
|
||
pelem->where = NULL;
|
||
|
||
pelem->dirname = strp;
|
||
pelem->dirnamelen = system_dirs_len[idx];
|
||
strp += system_dirs_len[idx] + 1;
|
||
|
||
if (pelem->dirname[0] != '/')
|
||
for (cnt = 0; cnt < ncapstr; ++cnt)
|
||
pelem->status[cnt] = existing;
|
||
else
|
||
for (cnt = 0; cnt < ncapstr; ++cnt)
|
||
pelem->status[cnt] = unknown;
|
||
|
||
pelem->next = (++idx == (sizeof (system_dirs_len)
|
||
/ sizeof (system_dirs_len[0]))
|
||
? NULL : (pelem + round_size));
|
||
|
||
pelem += round_size;
|
||
}
|
||
while (idx < sizeof (system_dirs_len) / sizeof (system_dirs_len[0]));
|
||
|
||
max_dirnamelen = SYSTEM_DIRS_MAX_LEN;
|
||
*aelem = NULL;
|
||
|
||
#ifdef PIC
|
||
/* This points to the map of the main object. */
|
||
l = _dl_loaded;
|
||
if (l != NULL)
|
||
{
|
||
assert (l->l_type != lt_loaded);
|
||
|
||
if (l->l_info[DT_RPATH])
|
||
/* Allocate room for the search path and fill in information
|
||
from RPATH. */
|
||
l->l_rpath_dirs =
|
||
decompose_rpath ((const void *) (l->l_info[DT_STRTAB]->d_un.d_ptr
|
||
+ l->l_info[DT_RPATH]->d_un.d_val),
|
||
l);
|
||
else
|
||
l->l_rpath_dirs = NULL;
|
||
}
|
||
#endif /* PIC */
|
||
|
||
if (llp != NULL && *llp != '\0')
|
||
{
|
||
size_t nllp;
|
||
const char *cp = llp;
|
||
|
||
/* Decompose the LD_LIBRARY_PATH contents. First determine how many
|
||
elements it has. */
|
||
nllp = 1;
|
||
while (*cp)
|
||
{
|
||
if (*cp == ':' || *cp == ';')
|
||
++nllp;
|
||
++cp;
|
||
}
|
||
|
||
env_path_list = (struct r_search_path_elem **)
|
||
malloc ((nllp + 1) * sizeof (struct r_search_path_elem *));
|
||
if (env_path_list == NULL)
|
||
_dl_signal_error (ENOMEM, NULL,
|
||
"cannot create cache for search path");
|
||
|
||
(void) fillin_rpath (local_strdup (llp), env_path_list, ":;",
|
||
__libc_enable_secure, "LD_LIBRARY_PATH", NULL);
|
||
}
|
||
}
|
||
|
||
|
||
/* Think twice before changing anything in this function. It is placed
|
||
here and prepared using the `alloca' magic to prevent it from being
|
||
inlined. The function is only called in case of an error. But then
|
||
performance does not count. The function used to be "inlinable" and
|
||
the compiled did so all the time. This increased the code size for
|
||
absolutely no good reason. */
|
||
#define LOSE(code, s) lose (code, fd, name, realname, l, s)
|
||
static void
|
||
__attribute__ ((noreturn))
|
||
lose (int code, int fd, const char *name, char *realname, struct link_map *l,
|
||
const char *msg)
|
||
{
|
||
/* The use of `alloca' here looks ridiculous but it helps. The goal
|
||
is to avoid the function from being inlined. There is no official
|
||
way to do this so we use this trick. gcc never inlines functions
|
||
which use `alloca'. */
|
||
int *a = alloca (sizeof (int));
|
||
a[0] = fd;
|
||
(void) __close (a[0]);
|
||
if (l != NULL)
|
||
{
|
||
/* Remove the stillborn object from the list and free it. */
|
||
if (l->l_prev)
|
||
l->l_prev->l_next = l->l_next;
|
||
if (l->l_next)
|
||
l->l_next->l_prev = l->l_prev;
|
||
free (l);
|
||
}
|
||
free (realname);
|
||
_dl_signal_error (code, name, msg);
|
||
}
|
||
|
||
|
||
/* Map in the shared object NAME, actually located in REALNAME, and already
|
||
opened on FD. */
|
||
|
||
#ifndef EXTERNAL_MAP_FROM_FD
|
||
static
|
||
#endif
|
||
struct link_map *
|
||
_dl_map_object_from_fd (const char *name, int fd, char *realname,
|
||
struct link_map *loader, int l_type)
|
||
{
|
||
/* This is the expected ELF header. */
|
||
#define ELF32_CLASS ELFCLASS32
|
||
#define ELF64_CLASS ELFCLASS64
|
||
static const unsigned char expected[EI_PAD] =
|
||
{
|
||
[EI_MAG0] = ELFMAG0,
|
||
[EI_MAG1] = ELFMAG1,
|
||
[EI_MAG2] = ELFMAG2,
|
||
[EI_MAG3] = ELFMAG3,
|
||
[EI_CLASS] = ELFW(CLASS),
|
||
[EI_DATA] = byteorder,
|
||
[EI_VERSION] = EV_CURRENT,
|
||
[EI_OSABI] = ELFOSABI_SYSV,
|
||
[EI_ABIVERSION] = 0
|
||
};
|
||
struct link_map *l = NULL;
|
||
|
||
inline caddr_t map_segment (ElfW(Addr) mapstart, size_t len,
|
||
int prot, int fixed, off_t offset)
|
||
{
|
||
caddr_t mapat = __mmap ((caddr_t) mapstart, len, prot,
|
||
fixed|MAP_COPY|MAP_FILE,
|
||
fd, offset);
|
||
if (mapat == MAP_FAILED)
|
||
LOSE (errno, "failed to map segment from shared object");
|
||
return mapat;
|
||
}
|
||
|
||
const ElfW(Ehdr) *header;
|
||
const ElfW(Phdr) *phdr;
|
||
const ElfW(Phdr) *ph;
|
||
size_t maplength;
|
||
int type;
|
||
char *readbuf;
|
||
ssize_t readlength;
|
||
struct stat st;
|
||
|
||
/* Get file information. */
|
||
if (__fxstat (_STAT_VER, fd, &st) < 0)
|
||
LOSE (errno, "cannot stat shared object");
|
||
|
||
/* Look again to see if the real name matched another already loaded. */
|
||
for (l = _dl_loaded; l; l = l->l_next)
|
||
if (l->l_ino == st.st_ino && l->l_dev == st.st_dev)
|
||
{
|
||
/* The object is already loaded.
|
||
Just bump its reference count and return it. */
|
||
__close (fd);
|
||
|
||
/* If the name is not in the list of names for this object add
|
||
it. */
|
||
free (realname);
|
||
add_name_to_object (l, name);
|
||
++l->l_opencount;
|
||
return l;
|
||
}
|
||
|
||
/* Print debugging message. */
|
||
if (_dl_debug_files)
|
||
_dl_debug_message (1, "file=", name, "; generating link map\n", NULL);
|
||
|
||
/* Read the header directly. */
|
||
readbuf = alloca (_dl_pagesize);
|
||
readlength = __libc_read (fd, readbuf, _dl_pagesize);
|
||
if (readlength < (ssize_t) sizeof (*header))
|
||
LOSE (errno, "cannot read file data");
|
||
header = (void *) readbuf;
|
||
|
||
/* Check the header for basic validity. */
|
||
if (memcmp (header->e_ident, expected, EI_PAD) != 0)
|
||
{
|
||
/* Something is wrong. */
|
||
if (*(Elf32_Word *) &header->e_ident !=
|
||
#if BYTE_ORDER == LITTLE_ENDIAN
|
||
((ELFMAG0 << (EI_MAG0 * 8)) |
|
||
(ELFMAG1 << (EI_MAG1 * 8)) |
|
||
(ELFMAG2 << (EI_MAG2 * 8)) |
|
||
(ELFMAG3 << (EI_MAG3 * 8)))
|
||
#else
|
||
((ELFMAG0 << (EI_MAG3 * 8)) |
|
||
(ELFMAG1 << (EI_MAG2 * 8)) |
|
||
(ELFMAG2 << (EI_MAG1 * 8)) |
|
||
(ELFMAG3 << (EI_MAG0 * 8)))
|
||
#endif
|
||
)
|
||
LOSE (0, "invalid ELF header");
|
||
if (header->e_ident[EI_CLASS] != ELFW(CLASS))
|
||
LOSE (0, "ELF file class not " STRING(__ELF_NATIVE_CLASS) "-bit");
|
||
if (header->e_ident[EI_DATA] != byteorder)
|
||
LOSE (0, "ELF file data encoding not " byteorder_name);
|
||
if (header->e_ident[EI_VERSION] != EV_CURRENT)
|
||
LOSE (0, "ELF file version ident not " STRING(EV_CURRENT));
|
||
/* XXX We should be able so set system specific versions which are
|
||
allowed here. */
|
||
if (header->e_ident[EI_OSABI] != ELFOSABI_SYSV)
|
||
LOSE (0, "ELF file OS ABI not " STRING(ELFOSABI_SYSV));
|
||
if (header->e_ident[EI_ABIVERSION] != 0)
|
||
LOSE (0, "ELF file ABI version not 0");
|
||
LOSE (0, "internal error");
|
||
}
|
||
|
||
if (header->e_version != EV_CURRENT)
|
||
LOSE (0, "ELF file version not " STRING(EV_CURRENT));
|
||
if (! elf_machine_matches_host (header->e_machine))
|
||
LOSE (0, "ELF file machine architecture not " ELF_MACHINE_NAME);
|
||
if (header->e_phentsize != sizeof (ElfW(Phdr)))
|
||
LOSE (0, "ELF file's phentsize not the expected size");
|
||
|
||
#ifndef MAP_ANON
|
||
# define MAP_ANON 0
|
||
if (_dl_zerofd == -1)
|
||
{
|
||
_dl_zerofd = _dl_sysdep_open_zero_fill ();
|
||
if (_dl_zerofd == -1)
|
||
{
|
||
__close (fd);
|
||
_dl_signal_error (errno, NULL, "cannot open zero fill device");
|
||
}
|
||
}
|
||
#endif
|
||
|
||
/* Enter the new object in the list of loaded objects. */
|
||
l = _dl_new_object (realname, name, l_type, loader);
|
||
if (! l)
|
||
LOSE (ENOMEM, "cannot create shared object descriptor");
|
||
l->l_opencount = 1;
|
||
|
||
/* Extract the remaining details we need from the ELF header
|
||
and then read in the program header table. */
|
||
l->l_entry = header->e_entry;
|
||
type = header->e_type;
|
||
l->l_phnum = header->e_phnum;
|
||
|
||
maplength = header->e_phnum * sizeof (ElfW(Phdr));
|
||
if (header->e_phoff + maplength <= readlength)
|
||
phdr = (void *) (readbuf + header->e_phoff);
|
||
else
|
||
{
|
||
phdr = alloca (maplength);
|
||
__lseek (fd, SEEK_SET, header->e_phoff);
|
||
if (__libc_read (fd, (void *) phdr, maplength) != maplength)
|
||
LOSE (errno, "cannot read file data");
|
||
}
|
||
|
||
{
|
||
/* Scan the program header table, collecting its load commands. */
|
||
struct loadcmd
|
||
{
|
||
ElfW(Addr) mapstart, mapend, dataend, allocend;
|
||
off_t mapoff;
|
||
int prot;
|
||
} loadcmds[l->l_phnum], *c;
|
||
size_t nloadcmds = 0;
|
||
|
||
/* The struct is initialized to zero so this is not necessary:
|
||
l->l_ld = 0;
|
||
l->l_phdr = 0;
|
||
l->l_addr = 0; */
|
||
for (ph = phdr; ph < &phdr[l->l_phnum]; ++ph)
|
||
switch (ph->p_type)
|
||
{
|
||
/* These entries tell us where to find things once the file's
|
||
segments are mapped in. We record the addresses it says
|
||
verbatim, and later correct for the run-time load address. */
|
||
case PT_DYNAMIC:
|
||
l->l_ld = (void *) ph->p_vaddr;
|
||
break;
|
||
case PT_PHDR:
|
||
l->l_phdr = (void *) ph->p_vaddr;
|
||
break;
|
||
|
||
case PT_LOAD:
|
||
/* A load command tells us to map in part of the file.
|
||
We record the load commands and process them all later. */
|
||
if (ph->p_align % _dl_pagesize != 0)
|
||
LOSE (0, "ELF load command alignment not page-aligned");
|
||
if ((ph->p_vaddr - ph->p_offset) % ph->p_align)
|
||
LOSE (0, "ELF load command address/offset not properly aligned");
|
||
{
|
||
struct loadcmd *c = &loadcmds[nloadcmds++];
|
||
c->mapstart = ph->p_vaddr & ~(ph->p_align - 1);
|
||
c->mapend = ((ph->p_vaddr + ph->p_filesz + _dl_pagesize - 1)
|
||
& ~(_dl_pagesize - 1));
|
||
c->dataend = ph->p_vaddr + ph->p_filesz;
|
||
c->allocend = ph->p_vaddr + ph->p_memsz;
|
||
c->mapoff = ph->p_offset & ~(ph->p_align - 1);
|
||
|
||
/* Optimize a common case. */
|
||
if ((PF_R | PF_W | PF_X) == 7
|
||
&& (PROT_READ | PROT_WRITE | PROT_EXEC) == 7)
|
||
c->prot = _dl_pf_to_prot[ph->p_flags & (PF_R | PF_W | PF_X)];
|
||
else
|
||
{
|
||
c->prot = 0;
|
||
if (ph->p_flags & PF_R)
|
||
c->prot |= PROT_READ;
|
||
if (ph->p_flags & PF_W)
|
||
c->prot |= PROT_WRITE;
|
||
if (ph->p_flags & PF_X)
|
||
c->prot |= PROT_EXEC;
|
||
}
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* Now process the load commands and map segments into memory. */
|
||
c = loadcmds;
|
||
|
||
/* Length of the sections to be loaded. */
|
||
maplength = loadcmds[nloadcmds - 1].allocend - c->mapstart;
|
||
|
||
if (type == ET_DYN || type == ET_REL)
|
||
{
|
||
/* This is a position-independent shared object. We can let the
|
||
kernel map it anywhere it likes, but we must have space for all
|
||
the segments in their specified positions relative to the first.
|
||
So we map the first segment without MAP_FIXED, but with its
|
||
extent increased to cover all the segments. Then we remove
|
||
access from excess portion, and there is known sufficient space
|
||
there to remap from the later segments.
|
||
|
||
As a refinement, sometimes we have an address that we would
|
||
prefer to map such objects at; but this is only a preference,
|
||
the OS can do whatever it likes. */
|
||
caddr_t mapat;
|
||
ElfW(Addr) mappref;
|
||
mappref = (ELF_PREFERRED_ADDRESS (loader, maplength, c->mapstart)
|
||
- MAP_BASE_ADDR (l));
|
||
mapat = map_segment (mappref, maplength, c->prot, 0, c->mapoff);
|
||
l->l_addr = (ElfW(Addr)) mapat - c->mapstart;
|
||
|
||
/* Change protection on the excess portion to disallow all access;
|
||
the portions we do not remap later will be inaccessible as if
|
||
unallocated. Then jump into the normal segment-mapping loop to
|
||
handle the portion of the segment past the end of the file
|
||
mapping. */
|
||
__mprotect ((caddr_t) (l->l_addr + c->mapend),
|
||
loadcmds[nloadcmds - 1].allocend - c->mapend,
|
||
0);
|
||
|
||
/* Remember which part of the address space this object uses. */
|
||
l->l_map_start = c->mapstart + l->l_addr;
|
||
l->l_map_end = l->l_map_start + maplength;
|
||
|
||
goto postmap;
|
||
}
|
||
else
|
||
{
|
||
/* Notify ELF_PREFERRED_ADDRESS that we have to load this one
|
||
fixed. */
|
||
ELF_FIXED_ADDRESS (loader, c->mapstart);
|
||
}
|
||
|
||
/* Remember which part of the address space this object uses. */
|
||
l->l_map_start = c->mapstart + l->l_addr;
|
||
l->l_map_end = l->l_map_start + maplength;
|
||
|
||
while (c < &loadcmds[nloadcmds])
|
||
{
|
||
if (c->mapend > c->mapstart)
|
||
/* Map the segment contents from the file. */
|
||
map_segment (l->l_addr + c->mapstart, c->mapend - c->mapstart,
|
||
c->prot, MAP_FIXED, c->mapoff);
|
||
|
||
postmap:
|
||
if (l->l_phdr == 0
|
||
&& c->mapoff <= header->e_phoff
|
||
&& (c->mapend - c->mapstart + c->mapoff
|
||
>= header->e_phoff + header->e_phnum * sizeof (ElfW(Phdr))))
|
||
/* Found the program header in this segment. */
|
||
l->l_phdr = (void *) (c->mapstart + header->e_phoff - c->mapoff);
|
||
|
||
if (c->allocend > c->dataend)
|
||
{
|
||
/* Extra zero pages should appear at the end of this segment,
|
||
after the data mapped from the file. */
|
||
ElfW(Addr) zero, zeroend, zeropage;
|
||
|
||
zero = l->l_addr + c->dataend;
|
||
zeroend = l->l_addr + c->allocend;
|
||
zeropage = (zero + _dl_pagesize - 1) & ~(_dl_pagesize - 1);
|
||
|
||
if (zeroend < zeropage)
|
||
/* All the extra data is in the last page of the segment.
|
||
We can just zero it. */
|
||
zeropage = zeroend;
|
||
|
||
if (zeropage > zero)
|
||
{
|
||
/* Zero the final part of the last page of the segment. */
|
||
if ((c->prot & PROT_WRITE) == 0)
|
||
{
|
||
/* Dag nab it. */
|
||
if (__mprotect ((caddr_t) (zero & ~(_dl_pagesize - 1)),
|
||
_dl_pagesize, c->prot|PROT_WRITE) < 0)
|
||
LOSE (errno, "cannot change memory protections");
|
||
}
|
||
memset ((void *) zero, 0, zeropage - zero);
|
||
if ((c->prot & PROT_WRITE) == 0)
|
||
__mprotect ((caddr_t) (zero & ~(_dl_pagesize - 1)),
|
||
_dl_pagesize, c->prot);
|
||
}
|
||
|
||
if (zeroend > zeropage)
|
||
{
|
||
/* Map the remaining zero pages in from the zero fill FD. */
|
||
caddr_t mapat;
|
||
mapat = __mmap ((caddr_t) zeropage, zeroend - zeropage,
|
||
c->prot, MAP_ANON|MAP_PRIVATE|MAP_FIXED,
|
||
ANONFD, 0);
|
||
if (mapat == MAP_FAILED)
|
||
LOSE (errno, "cannot map zero-fill pages");
|
||
}
|
||
}
|
||
|
||
++c;
|
||
}
|
||
|
||
if (l->l_phdr == NULL)
|
||
{
|
||
/* The program header is not contained in any of the segmenst.
|
||
We have to allocate memory ourself and copy it over from
|
||
out temporary place. */
|
||
ElfW(Phdr) *newp = (ElfW(Phdr) *) malloc (header->e_phnum
|
||
* sizeof (ElfW(Phdr)));
|
||
if (newp == NULL)
|
||
LOSE (ENOMEM, "cannot allocate memory for program header");
|
||
|
||
l->l_phdr = memcpy (newp, phdr,
|
||
(header->e_phnum * sizeof (ElfW(Phdr))));
|
||
l->l_phdr_allocated = 1;
|
||
}
|
||
else
|
||
/* Adjust the PT_PHDR value by the runtime load address. */
|
||
(ElfW(Addr)) l->l_phdr += l->l_addr;
|
||
}
|
||
|
||
/* We are done mapping in the file. We no longer need the descriptor. */
|
||
__close (fd);
|
||
|
||
if (l->l_type == lt_library && type == ET_EXEC)
|
||
l->l_type = lt_executable;
|
||
|
||
if (l->l_ld == 0)
|
||
{
|
||
if (type == ET_DYN)
|
||
LOSE (0, "object file has no dynamic section");
|
||
}
|
||
else
|
||
(ElfW(Addr)) l->l_ld += l->l_addr;
|
||
|
||
l->l_entry += l->l_addr;
|
||
|
||
if (_dl_debug_files)
|
||
{
|
||
const size_t nibbles = sizeof (void *) * 2;
|
||
char buf1[nibbles + 1];
|
||
char buf2[nibbles + 1];
|
||
char buf3[nibbles + 1];
|
||
|
||
buf1[nibbles] = '\0';
|
||
buf2[nibbles] = '\0';
|
||
buf3[nibbles] = '\0';
|
||
|
||
memset (buf1, '0', nibbles);
|
||
memset (buf2, '0', nibbles);
|
||
memset (buf3, '0', nibbles);
|
||
_itoa_word ((unsigned long int) l->l_ld, &buf1[nibbles], 16, 0);
|
||
_itoa_word ((unsigned long int) l->l_addr, &buf2[nibbles], 16, 0);
|
||
_itoa_word (maplength, &buf3[nibbles], 16, 0);
|
||
|
||
_dl_debug_message (1, " dynamic: 0x", buf1, " base: 0x", buf2,
|
||
" size: 0x", buf3, "\n", NULL);
|
||
memset (buf1, '0', nibbles);
|
||
memset (buf2, '0', nibbles);
|
||
memset (buf3, ' ', nibbles);
|
||
_itoa_word ((unsigned long int) l->l_entry, &buf1[nibbles], 16, 0);
|
||
_itoa_word ((unsigned long int) l->l_phdr, &buf2[nibbles], 16, 0);
|
||
_itoa_word (l->l_phnum, &buf3[nibbles], 10, 0);
|
||
_dl_debug_message (1, " entry: 0x", buf1, " phdr: 0x", buf2,
|
||
" phnum: ", buf3, "\n\n", NULL);
|
||
}
|
||
|
||
elf_get_dynamic_info (l->l_ld, l->l_addr, l->l_info);
|
||
if (l->l_info[DT_HASH])
|
||
_dl_setup_hash (l);
|
||
|
||
/* If this object has DT_SYMBOLIC set modify now its scope. We don't
|
||
have to do this for the main map. */
|
||
if (l->l_info[DT_SYMBOLIC] && &l->l_searchlist != l->l_scope[0])
|
||
{
|
||
/* Create an appropriate searchlist. It contains only this map.
|
||
|
||
XXX This is the definition of DT_SYMBOLIC in SysVr4. The old
|
||
GNU ld.so implementation had a different interpretation which
|
||
is more reasonable. We are prepared to add this possibility
|
||
back as part of a GNU extension of the ELF format. */
|
||
l->l_symbolic_searchlist.r_list =
|
||
(struct link_map **) malloc (sizeof (struct link_map *));
|
||
|
||
if (l->l_symbolic_searchlist.r_list == NULL)
|
||
LOSE (ENOMEM, "cannot create searchlist");
|
||
|
||
l->l_symbolic_searchlist.r_list[0] = l;
|
||
l->l_symbolic_searchlist.r_nlist = 1;
|
||
l->l_symbolic_searchlist.r_duplist = l->l_symbolic_searchlist.r_list;
|
||
l->l_symbolic_searchlist.r_nduplist = 1;
|
||
|
||
/* Now move the existing entries one back. */
|
||
memmove (&l->l_scope[1], &l->l_scope[0],
|
||
sizeof (l->l_scope) - sizeof (l->l_scope[0]));
|
||
|
||
/* Now add the new entry. */
|
||
l->l_scope[0] = &l->l_symbolic_searchlist;
|
||
}
|
||
|
||
/* Finally the file information. */
|
||
l->l_dev = st.st_dev;
|
||
l->l_ino = st.st_ino;
|
||
|
||
return l;
|
||
}
|
||
|
||
/* Print search path. */
|
||
static void
|
||
print_search_path (struct r_search_path_elem **list,
|
||
const char *what, const char *name)
|
||
{
|
||
char buf[max_dirnamelen + max_capstrlen];
|
||
int first = 1;
|
||
|
||
_dl_debug_message (1, " search path=", NULL);
|
||
|
||
while (*list != NULL && (*list)->what == what) /* Yes, ==. */
|
||
{
|
||
char *endp = __mempcpy (buf, (*list)->dirname, (*list)->dirnamelen);
|
||
size_t cnt;
|
||
|
||
for (cnt = 0; cnt < ncapstr; ++cnt)
|
||
if ((*list)->status[cnt] != nonexisting)
|
||
{
|
||
char *cp = __mempcpy (endp, capstr[cnt].str, capstr[cnt].len);
|
||
if (cp == buf || (cp == buf + 1 && buf[0] == '/'))
|
||
cp[0] = '\0';
|
||
else
|
||
cp[-1] = '\0';
|
||
_dl_debug_message (0, first ? "" : ":", buf, NULL);
|
||
first = 0;
|
||
}
|
||
|
||
++list;
|
||
}
|
||
|
||
if (name != NULL)
|
||
_dl_debug_message (0, "\t\t(", what, " from file ",
|
||
name[0] ? name : _dl_argv[0], ")\n", NULL);
|
||
else
|
||
_dl_debug_message (0, "\t\t(", what, ")\n", NULL);
|
||
}
|
||
|
||
/* Try to open NAME in one of the directories in DIRS.
|
||
Return the fd, or -1. If successful, fill in *REALNAME
|
||
with the malloc'd full directory name. */
|
||
|
||
static int
|
||
open_path (const char *name, size_t namelen, int preloaded,
|
||
struct r_search_path_elem **dirs,
|
||
char **realname)
|
||
{
|
||
char *buf;
|
||
int fd = -1;
|
||
const char *current_what = NULL;
|
||
|
||
if (dirs == NULL || *dirs == NULL)
|
||
{
|
||
__set_errno (ENOENT);
|
||
return -1;
|
||
}
|
||
|
||
buf = alloca (max_dirnamelen + max_capstrlen + namelen);
|
||
do
|
||
{
|
||
struct r_search_path_elem *this_dir = *dirs;
|
||
size_t buflen = 0;
|
||
size_t cnt;
|
||
char *edp;
|
||
|
||
/* If we are debugging the search for libraries print the path
|
||
now if it hasn't happened now. */
|
||
if (_dl_debug_libs && current_what != this_dir->what)
|
||
{
|
||
current_what = this_dir->what;
|
||
print_search_path (dirs, current_what, this_dir->where);
|
||
}
|
||
|
||
edp = (char *) __mempcpy (buf, this_dir->dirname, this_dir->dirnamelen);
|
||
for (cnt = 0; fd == -1 && cnt < ncapstr; ++cnt)
|
||
{
|
||
/* Skip this directory if we know it does not exist. */
|
||
if (this_dir->status[cnt] == nonexisting)
|
||
continue;
|
||
|
||
buflen =
|
||
((char *) __mempcpy (__mempcpy (edp,
|
||
capstr[cnt].str, capstr[cnt].len),
|
||
name, namelen)
|
||
- buf);
|
||
|
||
/* Print name we try if this is wanted. */
|
||
if (_dl_debug_libs)
|
||
_dl_debug_message (1, " trying file=", buf, "\n", NULL);
|
||
|
||
fd = __open (buf, O_RDONLY);
|
||
if (this_dir->status[cnt] == unknown)
|
||
{
|
||
if (fd != -1)
|
||
this_dir->status[cnt] = existing;
|
||
else
|
||
{
|
||
/* We failed to open machine dependent library. Let's
|
||
test whether there is any directory at all. */
|
||
struct stat st;
|
||
|
||
buf[buflen - namelen - 1] = '\0';
|
||
|
||
if (__xstat (_STAT_VER, buf, &st) != 0
|
||
|| ! S_ISDIR (st.st_mode))
|
||
/* The directory does not exist or it is no directory. */
|
||
this_dir->status[cnt] = nonexisting;
|
||
else
|
||
this_dir->status[cnt] = existing;
|
||
}
|
||
}
|
||
|
||
if (fd != -1 && preloaded && __libc_enable_secure)
|
||
{
|
||
/* This is an extra security effort to make sure nobody can
|
||
preload broken shared objects which are in the trusted
|
||
directories and so exploit the bugs. */
|
||
struct stat st;
|
||
|
||
if (__fxstat (_STAT_VER, fd, &st) != 0
|
||
|| (st.st_mode & S_ISUID) == 0)
|
||
{
|
||
/* The shared object cannot be tested for being SUID
|
||
or this bit is not set. In this case we must not
|
||
use this object. */
|
||
__close (fd);
|
||
fd = -1;
|
||
/* We simply ignore the file, signal this by setting
|
||
the error value which would have been set by `open'. */
|
||
errno = ENOENT;
|
||
}
|
||
}
|
||
}
|
||
|
||
if (fd != -1)
|
||
{
|
||
*realname = malloc (buflen);
|
||
if (*realname != NULL)
|
||
{
|
||
memcpy (*realname, buf, buflen);
|
||
return fd;
|
||
}
|
||
else
|
||
{
|
||
/* No memory for the name, we certainly won't be able
|
||
to load and link it. */
|
||
__close (fd);
|
||
return -1;
|
||
}
|
||
}
|
||
if (errno != ENOENT && errno != EACCES)
|
||
/* The file exists and is readable, but something went wrong. */
|
||
return -1;
|
||
}
|
||
while (*++dirs != NULL);
|
||
|
||
return -1;
|
||
}
|
||
|
||
/* Map in the shared object file NAME. */
|
||
|
||
struct link_map *
|
||
internal_function
|
||
_dl_map_object (struct link_map *loader, const char *name, int preloaded,
|
||
int type, int trace_mode)
|
||
{
|
||
int fd;
|
||
char *realname;
|
||
char *name_copy;
|
||
struct link_map *l;
|
||
|
||
/* Look for this name among those already loaded. */
|
||
for (l = _dl_loaded; l; l = l->l_next)
|
||
{
|
||
/* If the requested name matches the soname of a loaded object,
|
||
use that object. Elide this check for names that have not
|
||
yet been opened. */
|
||
if (l->l_opencount <= 0)
|
||
continue;
|
||
if (!_dl_name_match_p (name, l))
|
||
{
|
||
const char *soname;
|
||
|
||
if (l->l_info[DT_SONAME] == NULL)
|
||
continue;
|
||
|
||
soname = (const void *) (l->l_info[DT_STRTAB]->d_un.d_ptr
|
||
+ l->l_info[DT_SONAME]->d_un.d_val);
|
||
if (strcmp (name, soname) != 0)
|
||
continue;
|
||
|
||
/* We have a match on a new name -- cache it. */
|
||
add_name_to_object (l, soname);
|
||
}
|
||
|
||
/* We have a match -- bump the reference count and return it. */
|
||
++l->l_opencount;
|
||
return l;
|
||
}
|
||
|
||
/* Display information if we are debugging. */
|
||
if (_dl_debug_files && loader != NULL)
|
||
_dl_debug_message (1, "\nfile=", name, "; needed by ",
|
||
loader->l_name[0] ? loader->l_name : _dl_argv[0],
|
||
"\n", NULL);
|
||
|
||
if (strchr (name, '/') == NULL)
|
||
{
|
||
/* Search for NAME in several places. */
|
||
|
||
size_t namelen = strlen (name) + 1;
|
||
|
||
if (_dl_debug_libs)
|
||
_dl_debug_message (1, "find library=", name, "; searching\n", NULL);
|
||
|
||
fd = -1;
|
||
|
||
/* First try the DT_RPATH of the dependent object that caused NAME
|
||
to be loaded. Then that object's dependent, and on up. */
|
||
for (l = loader; fd == -1 && l; l = l->l_loader)
|
||
if (l->l_info[DT_RPATH])
|
||
{
|
||
/* Make sure the cache information is available. */
|
||
if (l->l_rpath_dirs == NULL)
|
||
{
|
||
size_t ptrval = (l->l_info[DT_STRTAB]->d_un.d_ptr
|
||
+ l->l_info[DT_RPATH]->d_un.d_val);
|
||
l->l_rpath_dirs =
|
||
decompose_rpath ((const char *) ptrval, l);
|
||
}
|
||
|
||
if (l->l_rpath_dirs != NULL)
|
||
fd = open_path (name, namelen, preloaded, l->l_rpath_dirs,
|
||
&realname);
|
||
}
|
||
|
||
/* If dynamically linked, try the DT_RPATH of the executable itself. */
|
||
l = _dl_loaded;
|
||
if (fd == -1 && l && l->l_type != lt_loaded && l != loader
|
||
&& l->l_rpath_dirs != NULL)
|
||
fd = open_path (name, namelen, preloaded, l->l_rpath_dirs, &realname);
|
||
|
||
/* Try the LD_LIBRARY_PATH environment variable. */
|
||
if (fd == -1 && env_path_list != NULL)
|
||
fd = open_path (name, namelen, preloaded, env_path_list, &realname);
|
||
|
||
if (fd == -1)
|
||
{
|
||
/* Check the list of libraries in the file /etc/ld.so.cache,
|
||
for compatibility with Linux's ldconfig program. */
|
||
extern const char *_dl_load_cache_lookup (const char *name);
|
||
const char *cached = _dl_load_cache_lookup (name);
|
||
if (cached)
|
||
{
|
||
fd = __open (cached, O_RDONLY);
|
||
if (fd != -1)
|
||
{
|
||
realname = local_strdup (cached);
|
||
if (realname == NULL)
|
||
{
|
||
__close (fd);
|
||
fd = -1;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Finally, try the default path. */
|
||
if (fd == -1)
|
||
fd = open_path (name, namelen, preloaded, rtld_search_dirs, &realname);
|
||
|
||
/* Add another newline when we a tracing the library loading. */
|
||
if (_dl_debug_libs)
|
||
_dl_debug_message (1, "\n", NULL);
|
||
}
|
||
else
|
||
{
|
||
/* The path may contain dynamic string tokens. */
|
||
realname = (loader
|
||
? expand_dynamic_string_token (loader, name)
|
||
: local_strdup (name));
|
||
if (realname == NULL)
|
||
fd = -1;
|
||
else
|
||
{
|
||
fd = __open (realname, O_RDONLY);
|
||
if (fd == -1)
|
||
free (realname);
|
||
}
|
||
}
|
||
|
||
if (fd == -1)
|
||
{
|
||
if (trace_mode)
|
||
{
|
||
/* We haven't found an appropriate library. But since we
|
||
are only interested in the list of libraries this isn't
|
||
so severe. Fake an entry with all the information we
|
||
have. */
|
||
static const ElfW(Symndx) dummy_bucket = STN_UNDEF;
|
||
|
||
/* Enter the new object in the list of loaded objects. */
|
||
if ((name_copy = local_strdup (name)) == NULL
|
||
|| (l = _dl_new_object (name_copy, name, type, loader)) == NULL)
|
||
_dl_signal_error (ENOMEM, name,
|
||
"cannot create shared object descriptor");
|
||
/* We use an opencount of 0 as a sign for the faked entry.
|
||
Since the descriptor is initialized with zero we do not
|
||
have do this here.
|
||
l->l_opencount = 0;
|
||
l->l_reserved = 0; */
|
||
l->l_buckets = &dummy_bucket;
|
||
l->l_nbuckets = 1;
|
||
l->l_relocated = 1;
|
||
|
||
return l;
|
||
}
|
||
else
|
||
_dl_signal_error (errno, name, "cannot open shared object file");
|
||
}
|
||
|
||
return _dl_map_object_from_fd (name, fd, realname, loader, type);
|
||
}
|