xref: /netbsd-src/sys/secmodel/overlay/secmodel_overlay.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /* $NetBSD: secmodel_overlay.c,v 1.8 2007/01/16 11:53:00 elad Exp $ */
2 /*-
3  * Copyright (c) 2006 Elad Efrat <elad@NetBSD.org>
4  * All rights reserved.
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  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: secmodel_overlay.c,v 1.8 2007/01/16 11:53:00 elad Exp $");
31 
32 #include <sys/types.h>
33 #include <sys/param.h>
34 #include <sys/kauth.h>
35 
36 #include <sys/sysctl.h>
37 
38 #include <secmodel/secmodel.h>
39 #include <secmodel/overlay/overlay.h>
40 
41 #include <secmodel/bsd44/bsd44.h>
42 #include <secmodel/bsd44/suser.h>
43 #include <secmodel/bsd44/securelevel.h>
44 
45 /*
46  * Fall-back settings.
47  */
48 #define	OVERLAY_ISCOPE_GENERIC	"org.netbsd.kauth.overlay.generic"
49 #define	OVERLAY_ISCOPE_SYSTEM	"org.netbsd.kauth.overlay.system"
50 #define	OVERLAY_ISCOPE_PROCESS	"org.netbsd.kauth.overlay.process"
51 #define	OVERLAY_ISCOPE_NETWORK	"org.netbsd.kauth.overlay.network"
52 #define	OVERLAY_ISCOPE_MACHDEP	"org.netbsd.kauth.overlay.machdep"
53 #define	OVERLAY_ISCOPE_DEVICE	"org.netbsd.kauth.overlay.device"
54 
55 static kauth_scope_t secmodel_overlay_iscope_generic;
56 static kauth_scope_t secmodel_overlay_iscope_system;
57 static kauth_scope_t secmodel_overlay_iscope_process;
58 static kauth_scope_t secmodel_overlay_iscope_network;
59 static kauth_scope_t secmodel_overlay_iscope_machdep;
60 static kauth_scope_t secmodel_overlay_iscope_device;
61 
62 extern int secmodel_bsd44_curtain;
63 
64 /*
65  * Initialize the overlay security model.
66  */
67 void
68 secmodel_overlay_init(void)
69 {
70 	/*
71 	 * Register internal fall-back scopes.
72 	 */
73 	secmodel_overlay_iscope_generic = kauth_register_scope(
74 	    OVERLAY_ISCOPE_GENERIC, NULL, NULL);
75 	secmodel_overlay_iscope_system = kauth_register_scope(
76 	    OVERLAY_ISCOPE_SYSTEM, NULL, NULL);
77 	secmodel_overlay_iscope_process = kauth_register_scope(
78 	    OVERLAY_ISCOPE_PROCESS, NULL, NULL);
79 	secmodel_overlay_iscope_network = kauth_register_scope(
80 	    OVERLAY_ISCOPE_NETWORK, NULL, NULL);
81 	secmodel_overlay_iscope_machdep = kauth_register_scope(
82 	    OVERLAY_ISCOPE_MACHDEP, NULL, NULL);
83 	secmodel_overlay_iscope_device = kauth_register_scope(
84 	    OVERLAY_ISCOPE_DEVICE, NULL, NULL);
85 
86 	/*
87 	 * Register fall-back listeners, from bsd44, to each internal
88 	 * fall-back scope.
89 	 */
90 	kauth_listen_scope(OVERLAY_ISCOPE_GENERIC,
91 	    secmodel_bsd44_suser_generic_cb, NULL);
92 
93 	kauth_listen_scope(OVERLAY_ISCOPE_SYSTEM,
94 	    secmodel_bsd44_suser_system_cb, NULL);
95 	kauth_listen_scope(OVERLAY_ISCOPE_SYSTEM,
96 	    secmodel_bsd44_securelevel_system_cb, NULL);
97 
98 	kauth_listen_scope(OVERLAY_ISCOPE_PROCESS,
99 	    secmodel_bsd44_suser_process_cb, NULL);
100 	kauth_listen_scope(OVERLAY_ISCOPE_PROCESS,
101 	    secmodel_bsd44_securelevel_process_cb, NULL);
102 
103 	kauth_listen_scope(OVERLAY_ISCOPE_NETWORK,
104 	    secmodel_bsd44_suser_network_cb, NULL);
105 	kauth_listen_scope(OVERLAY_ISCOPE_NETWORK,
106 	    secmodel_bsd44_securelevel_network_cb, NULL);
107 
108 	kauth_listen_scope(OVERLAY_ISCOPE_MACHDEP,
109 	    secmodel_bsd44_suser_machdep_cb, NULL);
110 	kauth_listen_scope(OVERLAY_ISCOPE_MACHDEP,
111 	    secmodel_bsd44_securelevel_machdep_cb, NULL);
112 
113 	kauth_listen_scope(OVERLAY_ISCOPE_DEVICE,
114 	    secmodel_bsd44_suser_device_cb, NULL);
115 	kauth_listen_scope(OVERLAY_ISCOPE_DEVICE,
116 	    secmodel_bsd44_securelevel_device_cb, NULL);
117 
118 	secmodel_bsd44_init();
119 }
120 
121 SYSCTL_SETUP(sysctl_security_overlay_setup,
122     "sysctl security overlay setup")
123 {
124 	const struct sysctlnode *rnode;
125 
126 	sysctl_createv(clog, 0, NULL, &rnode,
127 		       CTLFLAG_PERMANENT,
128 		       CTLTYPE_NODE, "security", NULL,
129 		       NULL, 0, NULL, 0,
130 		       CTL_SECURITY, CTL_EOL);
131 
132 	sysctl_createv(clog, 0, &rnode, &rnode,
133 		       CTLFLAG_PERMANENT,
134 		       CTLTYPE_NODE, "models", NULL,
135 		       NULL, 0, NULL, 0,
136 		       CTL_CREATE, CTL_EOL);
137 
138 	sysctl_createv(clog, 0, &rnode, &rnode,
139 		       CTLFLAG_PERMANENT,
140 		       CTLTYPE_NODE, "overlay",
141 		       SYSCTL_DESCR("Overlay security model on-top of bsd44, "),
142 		       NULL, 0, NULL, 0,
143 		       CTL_CREATE, CTL_EOL);
144 
145 	sysctl_createv(clog, 0, &rnode, NULL,
146 		       CTLFLAG_PERMANENT,
147 		       CTLTYPE_STRING, "name", NULL,
148 		       NULL, 0, __UNCONST("Overlay (on-top of bsd44)"), 0,
149 		       CTL_CREATE, CTL_EOL);
150 
151 	sysctl_createv(clog, 0, &rnode, NULL,
152 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
153 		       CTLTYPE_INT, "securelevel",
154 		       SYSCTL_DESCR("System security level"),
155 		       secmodel_bsd44_sysctl_securelevel, 0, NULL, 0,
156 		       CTL_CREATE, CTL_EOL);
157 
158 	sysctl_createv(clog, 0, &rnode, NULL,
159 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
160 		       CTLTYPE_INT, "curtain",
161 		       SYSCTL_DESCR("Curtain information about objects to "
162 				    "users not owning them."),
163 		       NULL, 0, &secmodel_bsd44_curtain, 0,
164 		       CTL_CREATE, CTL_EOL);
165 }
166 
167 /*
168  * Start the overlay security model.
169  */
170 void
171 secmodel_overlay_start(void)
172 {
173 	secmodel_overlay_init();
174 
175 	kauth_listen_scope(KAUTH_SCOPE_GENERIC,
176 	    secmodel_overlay_generic_cb, NULL);
177 	kauth_listen_scope(KAUTH_SCOPE_SYSTEM,
178 	    secmodel_overlay_system_cb, NULL);
179 	kauth_listen_scope(KAUTH_SCOPE_PROCESS,
180 	    secmodel_overlay_process_cb, NULL);
181 	kauth_listen_scope(KAUTH_SCOPE_NETWORK,
182 	    secmodel_overlay_network_cb, NULL);
183 	kauth_listen_scope(KAUTH_SCOPE_MACHDEP,
184 	    secmodel_overlay_machdep_cb, NULL);
185 	kauth_listen_scope(KAUTH_SCOPE_DEVICE,
186 	    secmodel_overlay_device_cb, NULL);
187 
188 	secmodel_register();
189 }
190 
191 void
192 secmodel_start(void)
193 {
194 	secmodel_overlay_start();
195 }
196 
197 /*
198  * Overlay listener for the generic scope.
199  */
200 int
201 secmodel_overlay_generic_cb(kauth_cred_t cred, kauth_action_t action,
202     void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
203 {
204 	int result;
205 
206 	result = KAUTH_RESULT_DEFER;
207 
208 	switch (action) {
209 	default:
210 		result = KAUTH_RESULT_DEFER;
211 		break;
212 	}
213 
214 	if (result == KAUTH_RESULT_DEFER) {
215 		result = kauth_authorize_action(
216 		    secmodel_overlay_iscope_generic, cred, action,
217 		    arg0, arg1, arg2, arg3);
218 	}
219 
220 	return (result);
221 }
222 
223 /*
224  * Overlay listener for the system scope.
225  */
226 int
227 secmodel_overlay_system_cb(kauth_cred_t cred, kauth_action_t action,
228     void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
229 {
230 	int result;
231 
232 	result = KAUTH_RESULT_DEFER;
233 
234 	switch (action) {
235 	default:
236 		result = KAUTH_RESULT_DEFER;
237 		break;
238 	}
239 
240 	if (result == KAUTH_RESULT_DEFER) {
241 		result = kauth_authorize_action(
242 		    secmodel_overlay_iscope_system, cred, action,
243 		    arg0, arg1, arg2, arg3);
244 	}
245 
246 	return (result);
247 }
248 
249 /*
250  * Overlay listener for the process scope.
251  */
252 int
253 secmodel_overlay_process_cb(kauth_cred_t cred, kauth_action_t action,
254     void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
255 {
256 	int result;
257 
258 	result = KAUTH_RESULT_DEFER;
259 
260 	switch (action) {
261 	default:
262 		result = KAUTH_RESULT_DEFER;
263 		break;
264 	}
265 
266 	if (result == KAUTH_RESULT_DEFER) {
267 		result = kauth_authorize_action(
268 		    secmodel_overlay_iscope_process, cred, action,
269 		    arg0, arg1, arg2, arg3);
270 	}
271 
272 	return (result);
273 }
274 
275 /*
276  * Overlay listener for the network scope.
277  */
278 int
279 secmodel_overlay_network_cb(kauth_cred_t cred, kauth_action_t action,
280     void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
281 {
282 	int result;
283 
284 	result = KAUTH_RESULT_DEFER;
285 
286 	switch (action) {
287 	default:
288 		result = KAUTH_RESULT_DEFER;
289 		break;
290 	}
291 
292 	if (result == KAUTH_RESULT_DEFER) {
293 		result = kauth_authorize_action(
294 		    secmodel_overlay_iscope_network, cred, action,
295 		    arg0, arg1, arg2, arg3);
296 	}
297 
298 	return (result);
299 }
300 
301 /*
302  * Overlay listener for the machdep scope.
303  */
304 int
305 secmodel_overlay_machdep_cb(kauth_cred_t cred, kauth_action_t action,
306     void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
307 {
308 	int result;
309 
310 	result = KAUTH_RESULT_DEFER;
311 
312 	switch (action) {
313 	default:
314 		result = KAUTH_RESULT_DEFER;
315 		break;
316 	}
317 
318 	if (result == KAUTH_RESULT_DEFER) {
319 		result = kauth_authorize_action(
320 		    secmodel_overlay_iscope_machdep, cred, action,
321 		    arg0, arg1, arg2, arg3);
322 	}
323 
324 	return (result);
325 }
326 
327 /*
328  * Overlay listener for the device scope.
329  */
330 int
331 secmodel_overlay_device_cb(kauth_cred_t cred, kauth_action_t action,
332     void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
333 {
334 	int result;
335 
336 	result = KAUTH_RESULT_DEFER;
337 
338 	switch (action) {
339 	default:
340 		result = KAUTH_RESULT_DEFER;
341 		break;
342 	}
343 
344 	if (result == KAUTH_RESULT_DEFER) {
345 		result = kauth_authorize_action(
346 		    secmodel_overlay_iscope_device, cred, action,
347 		    arg0, arg1, arg2, arg3);
348 	}
349 
350 	return (result);
351 }
352