1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2021 Florian Walpen <dev@submerge.ch> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/param.h> 29 #include <sys/conf.h> 30 #include <sys/kernel.h> 31 #include <sys/module.h> 32 #include <sys/priv.h> 33 #include <sys/sysctl.h> 34 #include <sys/ucred.h> 35 36 #include <security/mac/mac_policy.h> 37 38 SYSCTL_DECL(_security_mac); 39 40 static SYSCTL_NODE(_security_mac, OID_AUTO, priority, 41 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 42 "mac_priority policy controls"); 43 44 static int realtime_enabled = 1; 45 SYSCTL_INT(_security_mac_priority, OID_AUTO, realtime, CTLFLAG_RWTUN, 46 &realtime_enabled, 0, 47 "Enable realtime policy for group realtime_gid"); 48 49 static int realtime_gid = GID_RT_PRIO; 50 SYSCTL_INT(_security_mac_priority, OID_AUTO, realtime_gid, CTLFLAG_RWTUN, 51 &realtime_gid, 0, 52 "Group id of the realtime privilege group"); 53 54 static int 55 priority_priv_grant(struct ucred *cred, int priv) 56 { 57 if (priv == PRIV_SCHED_RTPRIO && realtime_enabled && 58 groupmember(realtime_gid, cred)) 59 return (0); 60 return (EPERM); 61 } 62 63 static struct mac_policy_ops priority_ops = { 64 .mpo_priv_grant = priority_priv_grant, 65 }; 66 67 MAC_POLICY_SET(&priority_ops, mac_priority, "MAC/priority", 68 MPC_LOADTIME_FLAG_UNLOADOK, NULL); 69