Name
setreuid, setregid — set real and/or effective user
or group ID
Synopsis
int
setreuid( |
uid_t |
ruid, |
| |
uid_t |
euid); |
int
setregid( |
gid_t |
rgid, |
| |
gid_t |
egid); |
DESCRIPTION
setreuid() sets real and
effective user IDs of the current process.
Supplying a value of −1 for either the real or
effective user ID forces the system to leave that ID
unchanged.
Unprivileged processes may only set the effective user ID
to the real user ID, the effective user ID or the saved
set-user-ID.
POSIX: It is unspecified whether unprivileged processes
may set the real user ID to the real user ID, the effective
user ID or the saved set-user-ID.
Linux: Unprivileged users may only set the real user ID to
the real user ID or the effective user ID.
Linux: If the real user ID is set or the effective user ID
is set to a value not equal to the previous real user ID, the
saved set-user-ID will be set to the new effective user
ID.
Completely analogously, setregid() sets real and effective group
ID's of the current process, and all of the above holds with
"group" instead of "user".
RETURN VALUE
On success, zero is returned. On error, −1 is
returned, and errno is set
appropriately.
ERRORS
- EPERM
-
The current process is not privileged (Linux: does
not have the CAP_SETUID
capability in the case of setreuid(), or the CAP_SETGID capability in the case of
setregid()) and a change
other than (i) swapping the effective user (group) ID
with the real user (group) ID, or (ii) setting one to
the value of the other or (iii) setting the effective
user (group) ID to the value of the saved set-user-ID
(saved set-group-ID) was specified.
CONFORMING TO
POSIX.1-2001, 4.3BSD (the setreuid() and setregid() function calls first appeared in
4.2BSD).
NOTES
Setting the effective user (group) ID to the saved
set-user-ID (saved set-group-ID) is possible since Linux
1.1.37 (1.1.38).
SEE ALSO
getgid(2), getuid(2), seteuid(2), setgid(2), setresuid(2), setuid(2), capabilities(7)
Copyright (c) 1983, 1991 The Regents of the University of California.
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. All advertising materials mentioning features or use of this software
must display the following acknowledgement:
This product includes software developed by the University of
California, Berkeley and its contributors.
4. Neither the name of the University nor the names of its contributors
may be used to endorse or promote products derived from this software
without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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SUCH DAMAGE.
@(#)setregid.2
6.4 (Berkeley) 3/10/91
Modified Sat Jul 24 09:08:49 1993 by Rik Faith <faith@cs.unc.edu>
Portions extracted from linux/kernel/sys.c:
Copyright (C) 1991, 1992 Linus Torvalds
May be distributed under the GNU General Public License
Changes: 1994-07-29 by Wilf <G.Wilford@ee.surrey.ac.uk>
1994-08-02 by Wilf due to change in kernel.
2004-07-04 by aeb
2004-05-27 by Michael Kerrisk
|
