gems-kernel/source/THIRDPARTY/xnu/bsd/kern/kern_priv.c
2024-06-03 11:29:39 -05:00

134 lines
4.4 KiB
C

/*
* Copyright (c) 2010 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*-
* Copyright (c) 2006 nCircle Network Security, Inc.
* Copyright (c) 2009 Robert N. M. Watson
* All rights reserved.
*
* This software was developed by Robert N. M. Watson for the TrustedBSD
* Project under contract to nCircle Network Security, Inc.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR, NCIRCLE NETWORK SECURITY,
* INC., 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 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.
*/
#include <sys/cdefs.h>
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <sys/kauth.h>
#if CONFIG_MACF
#include <security/mac_framework.h>
#endif
int proc_check_footprint_priv(void);
/*
* Check a credential for privilege. Lots of good reasons to deny privilege;
* only a few to grant it.
*/
int
priv_check_cred(kauth_cred_t cred, int priv, int flags)
{
#if !CONFIG_MACF
#pragma unused(priv)
#endif
int error;
/*
* We first evaluate policies that may deny the granting of
* privilege unilaterally.
*/
#if CONFIG_MACF
error = mac_priv_check(cred, priv);
if (error) {
goto out;
}
#endif
/* Only grant all privileges to root if DEFAULT_UNPRIVELEGED flag is NOT set. */
if (!(flags & PRIVCHECK_DEFAULT_UNPRIVILEGED_FLAG)) {
/*
* Having determined if privilege is restricted by various policies,
* now determine if privilege is granted. At this point, any policy
* may grant privilege. For now, we allow short-circuit boolean
* evaluation, so may not call all policies. Perhaps we should.
*/
if (kauth_cred_getuid(cred) == 0) {
error = 0;
goto out;
}
}
/*
* Now check with MAC, if enabled, to see if a policy module grants
* privilege.
*/
#if CONFIG_MACF
if (mac_priv_grant(cred, priv) == 0) {
error = 0;
goto out;
}
#endif
/*
* The default is deny, so if no policies have granted it, reject
* with a privilege error here.
*/
error = EPERM;
out:
return error;
}
int
proc_check_footprint_priv(void)
{
return priv_check_cred(kauth_cred_get(), PRIV_VM_FOOTPRINT_LIMIT, 0);
}