sysdeps/unix/sysv/linux/i386/setresuid.c

   1 /* Copyright (C) 1998, 2000, 2002, 2003, 2004 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #include <errno.h>
  20 #include <unistd.h>
  21 #include <setxid.h>
  22 #include <linux/posix_types.h>
  23 #include "kernel-features.h"
  24
  25
  26 #if defined __NR_setresuid || defined __NR_setresuid32
  27
  28 # ifdef __NR_setresuid32
  29 #  if __ASSUME_32BITUIDS == 0
  30 /* This variable is shared with all files that need to check for 32bit
  31    uids.  */
  32 extern int __libc_missing_32bit_uids;
  33 #  endif
  34 # endif /* __NR_setresuid32 */
  35
  36 int
  37 __setresuid (uid_t ruid, uid_t euid, uid_t suid)
  38 {
  39   int result;
  40
  41 # if __ASSUME_32BITUIDS > 0 || !defined __NR_setresuid
  42   result = INLINE_SETXID_SYSCALL (setresuid32, 3, ruid, euid, suid);
  43 # else
  44 #  ifdef __NR_setresuid32
  45   if (__libc_missing_32bit_uids <= 0)
  46     {
  47       int saved_errno = errno;
  48
  49       result = INLINE_SETXID_SYSCALL (setresuid32, 3, ruid, euid, suid);
  50       if (result == 0)
  51         goto out;
  52       if (errno != ENOSYS)
  53         return result;
  54
  55       __set_errno (saved_errno);
  56       __libc_missing_32bit_uids = 1;
  57     }
  58 #  endif /* __NR_setresuid32 */
  59
  60   if (((ruid + 1) > (uid_t) ((__kernel_uid_t) -1U))
  61       || ((euid + 1) > (uid_t) ((__kernel_uid_t) -1U))
  62       || ((suid + 1) > (uid_t) ((__kernel_uid_t) -1U)))
  63     {
  64       __set_errno (EINVAL);
  65       return -1;
  66     }
  67
  68   result = INLINE_SETXID_SYSCALL (setresuid, 3, ruid, euid, suid);
  69 #  ifdef __NR_setresuid32
  70  out:
  71 #  endif
  72 # endif
  73
  74   return result;
  75 }
  76 libc_hidden_def (__setresuid)
  77 #ifndef __setresuid
  78 weak_alias (__setresuid, setresuid)
  79 #endif
  80
  81 #else
  82
  83 #include <sysdeps/generic/setresuid.c>
  84
  85 #endif