xref: /freebsd/sys/security/mac/mac_system.c (revision 685dc743)
1 /*-
2  * Copyright (c) 2002-2003 Networks Associates Technology, Inc.
3  * Copyright (c) 2006 SPARTA, Inc.
4  * Copyright (c) 2007, 2009 Robert N. M. Watson
5  * All rights reserved.
6  *
7  * This software was developed for the FreeBSD Project in part by Network
8  * Associates Laboratories, the Security Research Division of Network
9  * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
10  * as part of the DARPA CHATS research program.
11  *
12  * Portions of this software were developed by Robert Watson for the
13  * TrustedBSD Project.
14  *
15  * This software was enhanced by SPARTA ISSO under SPAWAR contract
16  * N66001-04-C-6019 ("SEFOS").
17  *
18  * This software was developed at the University of Cambridge Computer
19  * Laboratory with support from a grant from Google, Inc.
20  *
21  * Redistribution and use in source and binary forms, with or without
22  * modification, are permitted provided that the following conditions
23  * are met:
24  * 1. Redistributions of source code must retain the above copyright
25  *    notice, this list of conditions and the following disclaimer.
26  * 2. Redistributions in binary form must reproduce the above copyright
27  *    notice, this list of conditions and the following disclaimer in the
28  *    documentation and/or other materials provided with the distribution.
29  *
30  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
31  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
32  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
34  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
35  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
36  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
37  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
38  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
39  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40  * SUCH DAMAGE.
41  */
42 
43 /*
44  * MAC Framework entry points relating to overall operation of system,
45  * including global services such as the kernel environment and loadable
46  * modules.
47  *
48  * System checks often align with existing privilege checks, but provide
49  * additional security context that may be relevant to policies, such as the
50  * specific object being operated on.
51  */
52 
53 #include <sys/cdefs.h>
54 #include "opt_mac.h"
55 
56 #include <sys/param.h>
57 #include <sys/kernel.h>
58 #include <sys/lock.h>
59 #include <sys/malloc.h>
60 #include <sys/module.h>
61 #include <sys/mutex.h>
62 #include <sys/sdt.h>
63 #include <sys/systm.h>
64 #include <sys/vnode.h>
65 #include <sys/sysctl.h>
66 
67 #include <security/mac/mac_framework.h>
68 #include <security/mac/mac_internal.h>
69 #include <security/mac/mac_policy.h>
70 
71 MAC_CHECK_PROBE_DEFINE1(kenv_check_dump, "struct ucred *");
72 
73 int
mac_kenv_check_dump(struct ucred * cred)74 mac_kenv_check_dump(struct ucred *cred)
75 {
76 	int error;
77 
78 	MAC_POLICY_CHECK_NOSLEEP(kenv_check_dump, cred);
79 	MAC_CHECK_PROBE1(kenv_check_dump, error, cred);
80 
81 	return (error);
82 }
83 
84 MAC_CHECK_PROBE_DEFINE2(kenv_check_get, "struct ucred *", "char *");
85 
86 int
mac_kenv_check_get(struct ucred * cred,char * name)87 mac_kenv_check_get(struct ucred *cred, char *name)
88 {
89 	int error;
90 
91 	MAC_POLICY_CHECK_NOSLEEP(kenv_check_get, cred, name);
92 	MAC_CHECK_PROBE2(kenv_check_get, error, cred, name);
93 
94 	return (error);
95 }
96 
97 MAC_CHECK_PROBE_DEFINE3(kenv_check_set, "struct ucred *", "char *",
98     "char *");
99 
100 int
mac_kenv_check_set(struct ucred * cred,char * name,char * value)101 mac_kenv_check_set(struct ucred *cred, char *name, char *value)
102 {
103 	int error;
104 
105 	MAC_POLICY_CHECK_NOSLEEP(kenv_check_set, cred, name, value);
106 	MAC_CHECK_PROBE3(kenv_check_set, error, cred, name, value);
107 
108 	return (error);
109 }
110 
111 MAC_CHECK_PROBE_DEFINE2(kenv_check_unset, "struct ucred *", "char *");
112 
113 int
mac_kenv_check_unset(struct ucred * cred,char * name)114 mac_kenv_check_unset(struct ucred *cred, char *name)
115 {
116 	int error;
117 
118 	MAC_POLICY_CHECK_NOSLEEP(kenv_check_unset, cred, name);
119 	MAC_CHECK_PROBE2(kenv_check_unset, error, cred, name);
120 
121 	return (error);
122 }
123 
124 MAC_CHECK_PROBE_DEFINE2(kld_check_load, "struct ucred *", "struct vnode *");
125 
126 int
mac_kld_check_load(struct ucred * cred,struct vnode * vp)127 mac_kld_check_load(struct ucred *cred, struct vnode *vp)
128 {
129 	int error;
130 
131 	ASSERT_VOP_LOCKED(vp, "mac_kld_check_load");
132 
133 	MAC_POLICY_CHECK(kld_check_load, cred, vp, vp->v_label);
134 	MAC_CHECK_PROBE2(kld_check_load, error, cred, vp);
135 
136 	return (error);
137 }
138 
139 MAC_CHECK_PROBE_DEFINE1(kld_check_stat, "struct ucred *");
140 
141 int
mac_kld_check_stat(struct ucred * cred)142 mac_kld_check_stat(struct ucred *cred)
143 {
144 	int error;
145 
146 	MAC_POLICY_CHECK_NOSLEEP(kld_check_stat, cred);
147 	MAC_CHECK_PROBE1(kld_check_stat, error, cred);
148 
149 	return (error);
150 }
151 
152 MAC_CHECK_PROBE_DEFINE2(system_check_acct, "struct ucred *",
153     "struct vnode *");
154 
155 int
mac_system_check_acct(struct ucred * cred,struct vnode * vp)156 mac_system_check_acct(struct ucred *cred, struct vnode *vp)
157 {
158 	int error;
159 
160 	if (vp != NULL) {
161 		ASSERT_VOP_LOCKED(vp, "mac_system_check_acct");
162 	}
163 
164 	MAC_POLICY_CHECK(system_check_acct, cred, vp,
165 	    vp != NULL ? vp->v_label : NULL);
166 	MAC_CHECK_PROBE2(system_check_acct, error, cred, vp);
167 
168 	return (error);
169 }
170 
171 MAC_CHECK_PROBE_DEFINE2(system_check_reboot, "struct ucred *", "int");
172 
173 int
mac_system_check_reboot(struct ucred * cred,int howto)174 mac_system_check_reboot(struct ucred *cred, int howto)
175 {
176 	int error;
177 
178 	MAC_POLICY_CHECK_NOSLEEP(system_check_reboot, cred, howto);
179 	MAC_CHECK_PROBE2(system_check_reboot, error, cred, howto);
180 
181 	return (error);
182 }
183 
184 MAC_CHECK_PROBE_DEFINE2(system_check_swapon, "struct ucred *",
185     "struct vnode *");
186 
187 int
mac_system_check_swapon(struct ucred * cred,struct vnode * vp)188 mac_system_check_swapon(struct ucred *cred, struct vnode *vp)
189 {
190 	int error;
191 
192 	ASSERT_VOP_LOCKED(vp, "mac_system_check_swapon");
193 
194 	MAC_POLICY_CHECK(system_check_swapon, cred, vp, vp->v_label);
195 	MAC_CHECK_PROBE2(system_check_swapon, error, cred, vp);
196 
197 	return (error);
198 }
199 
200 MAC_CHECK_PROBE_DEFINE2(system_check_swapoff, "struct ucred *",
201     "struct vnode *");
202 
203 int
mac_system_check_swapoff(struct ucred * cred,struct vnode * vp)204 mac_system_check_swapoff(struct ucred *cred, struct vnode *vp)
205 {
206 	int error;
207 
208 	ASSERT_VOP_LOCKED(vp, "mac_system_check_swapoff");
209 
210 	MAC_POLICY_CHECK(system_check_swapoff, cred, vp, vp->v_label);
211 	MAC_CHECK_PROBE2(system_check_swapoff, error, cred, vp);
212 
213 	return (error);
214 }
215 
216 MAC_CHECK_PROBE_DEFINE3(system_check_sysctl, "struct ucred *",
217     "struct sysctl_oid *", "struct sysctl_req *");
218 
219 int
mac_system_check_sysctl(struct ucred * cred,struct sysctl_oid * oidp,void * arg1,int arg2,struct sysctl_req * req)220 mac_system_check_sysctl(struct ucred *cred, struct sysctl_oid *oidp,
221     void *arg1, int arg2, struct sysctl_req *req)
222 {
223 	int error;
224 
225 	/*
226 	 * XXXMAC: We would very much like to assert the SYSCTL_LOCK here,
227 	 * but since it's not exported from kern_sysctl.c, we can't.
228 	 */
229 	MAC_POLICY_CHECK_NOSLEEP(system_check_sysctl, cred, oidp, arg1, arg2,
230 	    req);
231 	MAC_CHECK_PROBE3(system_check_sysctl, error, cred, oidp, req);
232 
233 	return (error);
234 }
235