mirror of
https://git.hardenedbsd.org/hardenedbsd/HardenedBSD.git
synced 2024-11-22 11:14:18 +01:00
108 lines
3.9 KiB
C
108 lines
3.9 KiB
C
/*-
|
|
* privs.h - header for privileged operations
|
|
*
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*
|
|
* Copyright (C) 1993 Thomas Koenig
|
|
*
|
|
* 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. The name of the author(s) may not be used to endorse or promote
|
|
* products derived from this software without specific prior written
|
|
* permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``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 AUTHOR(S) 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, WETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
|
|
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#ifndef _PRIVS_H
|
|
#define _PRIVS_H
|
|
|
|
#include <unistd.h>
|
|
|
|
/* Relinquish privileges temporarily for a setuid or setgid program
|
|
* with the option of getting them back later. This is done by
|
|
* utilizing POSIX saved user and group IDs. Call RELINQUISH_PRIVS once
|
|
* at the beginning of the main program. This will cause all operations
|
|
* to be executed with the real userid. When you need the privileges
|
|
* of the setuid/setgid invocation, call PRIV_START; when you no longer
|
|
* need it, call PRIV_END. Note that it is an error to call PRIV_START
|
|
* and not PRIV_END within the same function.
|
|
*
|
|
* Use RELINQUISH_PRIVS_ROOT(a,b) if your program started out running
|
|
* as root, and you want to drop back the effective userid to a
|
|
* and the effective group id to b, with the option to get them back
|
|
* later.
|
|
*
|
|
* If you no longer need root privileges, but those of some other
|
|
* userid/groupid, you can call REDUCE_PRIV(a,b) when your effective
|
|
* is the user's.
|
|
*
|
|
* Problems: Do not use return between PRIV_START and PRIV_END; this
|
|
* will cause the program to continue running in an unprivileged
|
|
* state.
|
|
*
|
|
* It is NOT safe to call exec(), system() or popen() with a user-
|
|
* supplied program (i.e. without carefully checking PATH and any
|
|
* library load paths) with relinquished privileges; the called program
|
|
* can acquire them just as easily. Set both effective and real userid
|
|
* to the real userid before calling any of them.
|
|
*/
|
|
|
|
extern uid_t real_uid, effective_uid;
|
|
extern gid_t real_gid, effective_gid;
|
|
|
|
#ifdef MAIN
|
|
uid_t real_uid, effective_uid;
|
|
gid_t real_gid, effective_gid;
|
|
#endif
|
|
|
|
#define RELINQUISH_PRIVS { \
|
|
real_uid = getuid(); \
|
|
effective_uid = geteuid(); \
|
|
real_gid = getgid(); \
|
|
effective_gid = getegid(); \
|
|
if (seteuid(real_uid) != 0) err(1, "seteuid failed"); \
|
|
if (setegid(real_gid) != 0) err(1, "setegid failed"); \
|
|
}
|
|
|
|
#define RELINQUISH_PRIVS_ROOT(a, b) { \
|
|
real_uid = (a); \
|
|
effective_uid = geteuid(); \
|
|
real_gid = (b); \
|
|
effective_gid = getegid(); \
|
|
if (setegid(real_gid) != 0) err(1, "setegid failed"); \
|
|
if (seteuid(real_uid) != 0) err(1, "seteuid failed"); \
|
|
}
|
|
|
|
#define PRIV_START { \
|
|
if (seteuid(effective_uid) != 0) err(1, "seteuid failed"); \
|
|
if (setegid(effective_gid) != 0) err(1, "setegid failed"); \
|
|
}
|
|
|
|
#define PRIV_END { \
|
|
if (setegid(real_gid) != 0) err(1, "setegid failed"); \
|
|
if (seteuid(real_uid) != 0) err(1, "seteuid failed"); \
|
|
}
|
|
|
|
#define REDUCE_PRIV(a, b) { \
|
|
PRIV_START \
|
|
effective_uid = (a); \
|
|
effective_gid = (b); \
|
|
if (setregid((gid_t)-1, effective_gid) != 0) err(1, "setregid failed"); \
|
|
if (setreuid((uid_t)-1, effective_uid) != 0) err(1, "setreuid failed"); \
|
|
PRIV_END \
|
|
}
|
|
#endif
|