glibc/sysdeps/generic/dl-sysdep.c

99 lines
2.3 KiB
C

/* Operating system support for run-time dynamic linker. Generic Unix version.
Copyright (C) 1995 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., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#include <elf.h>
#include <sys/types.h>
#include <fcntl.h>
#include <link.h>
Elf32_Addr
_dl_sysdep_start (void **start_argptr,
void (*dl_main) (const Elf32_Phdr *phdr, Elf32_Word phnum,
Elf32_Addr *user_entry))
{
const Elf32_Phdr *phdr;
Elf32_Word phnum;
Elf32_Addr user_entry;
Elf32_auxv_t *av;
uid_t uid, euid;
gid_t gid, egid;
_dl_argc = *(int *) start_argptr;
_dl_argv = start_argptr + 1;
_environ = &_dl_argv[_dl_argc + 1];
start_argptr = (void **) _environ;
while (*start_argptr)
++start_argptr;
for (av = ++start_argptr; av->a_type != AT_NULL; ++av)
switch (av->a_type)
{
case AT_PHDR:
phdr = av->a_un.a_ptr;
break;
case AT_PHNUM:
phnum = av->a_un.a_val;
break;
case AT_ENTRY:
user_entry = av->a_un.a_val;
case AT_UID:
uid = av->a_un.a_val;
break;
case AT_GID:
gid = av->a_un.a_val;
break;
case AT_EUID:
euid = av->a_un.a_val;
break;
case AT_EGID:
egid = av->a_un.a_val;
break;
}
_dl_secure = uid != euid || gid != egid;
(*dl_main) (phdr, phnum, &user_entry);
start_argptr[-1] = (void *) user_entry;
}
int
_dl_sysdep_open_zero_fill (void)
{
return open ("/dev/zero", O_RDONLY);
}
#include <stdarg.h>
void
_dl_sysdep_fatal (const char *msg, ...)
{
va_list ap;
va_start (ap, msg);
do
{
size_t len = strlen (msg);
write (STDERR_FILENO, msg, len);
msg = va_arg (ap, const char *);
} while (msg);
va_end (ap);
_exit (127);
}