xref: /netbsd-src/sys/secmodel/overlay/secmodel_overlay.c (revision a5847cc334d9a7029f6352b847e9e8d71a0f9e0c)
1 /* $NetBSD: secmodel_overlay.c,v 1.10 2009/10/02 18:50:13 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 1.10 2009/10/02 18:50:13 elad Exp $");
31 
32 #include <sys/types.h>
33 #include <sys/param.h>
34 #include <sys/kauth.h>
35 #include <sys/module.h>
36 
37 #include <sys/sysctl.h>
38 
39 #include <secmodel/overlay/overlay.h>
40 
41 #include <secmodel/bsd44/bsd44.h>
42 #include <secmodel/suser/suser.h>
43 #include <secmodel/securelevel/securelevel.h>
44 
45 MODULE(MODULE_CLASS_SECMODEL, secmodel_overlay, "secmodel_bsd44");
46 
47 /*
48  * Fall-back settings.
49  */
50 #define	OVERLAY_ISCOPE_GENERIC	"org.netbsd.kauth.overlay.generic"
51 #define	OVERLAY_ISCOPE_SYSTEM	"org.netbsd.kauth.overlay.system"
52 #define	OVERLAY_ISCOPE_PROCESS	"org.netbsd.kauth.overlay.process"
53 #define	OVERLAY_ISCOPE_NETWORK	"org.netbsd.kauth.overlay.network"
54 #define	OVERLAY_ISCOPE_MACHDEP	"org.netbsd.kauth.overlay.machdep"
55 #define	OVERLAY_ISCOPE_DEVICE	"org.netbsd.kauth.overlay.device"
56 #define	OVERLAY_ISCOPE_VNODE	"org.netbsd.kauth.overlay.vnode"
57 
58 static kauth_scope_t secmodel_overlay_iscope_generic;
59 static kauth_scope_t secmodel_overlay_iscope_system;
60 static kauth_scope_t secmodel_overlay_iscope_process;
61 static kauth_scope_t secmodel_overlay_iscope_network;
62 static kauth_scope_t secmodel_overlay_iscope_machdep;
63 static kauth_scope_t secmodel_overlay_iscope_device;
64 static kauth_scope_t secmodel_overlay_iscope_vnode;
65 
66 static kauth_listener_t l_generic, l_system, l_process, l_network, l_machdep,
67     l_device, l_vnode;
68 
69 static struct sysctllog *sysctl_overlay_log;
70 
71 /*
72  * Initialize the overlay security model.
73  */
74 void
75 secmodel_overlay_init(void)
76 {
77 	/*
78 	 * Register internal fall-back scopes.
79 	 */
80 	secmodel_overlay_iscope_generic = kauth_register_scope(
81 	    OVERLAY_ISCOPE_GENERIC, NULL, NULL);
82 	secmodel_overlay_iscope_system = kauth_register_scope(
83 	    OVERLAY_ISCOPE_SYSTEM, NULL, NULL);
84 	secmodel_overlay_iscope_process = kauth_register_scope(
85 	    OVERLAY_ISCOPE_PROCESS, NULL, NULL);
86 	secmodel_overlay_iscope_network = kauth_register_scope(
87 	    OVERLAY_ISCOPE_NETWORK, NULL, NULL);
88 	secmodel_overlay_iscope_machdep = kauth_register_scope(
89 	    OVERLAY_ISCOPE_MACHDEP, NULL, NULL);
90 	secmodel_overlay_iscope_device = kauth_register_scope(
91 	    OVERLAY_ISCOPE_DEVICE, NULL, NULL);
92 	secmodel_overlay_iscope_vnode = kauth_register_scope(
93 	    OVERLAY_ISCOPE_VNODE, NULL, NULL);
94 
95 	/*
96 	 * Register fall-back listeners, from suser and securelevel, to each
97 	 * internal scope.
98 	 */
99 	kauth_listen_scope(OVERLAY_ISCOPE_GENERIC,
100 	    secmodel_suser_generic_cb, NULL);
101 
102 	kauth_listen_scope(OVERLAY_ISCOPE_SYSTEM,
103 	    secmodel_suser_system_cb, NULL);
104 	kauth_listen_scope(OVERLAY_ISCOPE_SYSTEM,
105 	    secmodel_securelevel_system_cb, NULL);
106 
107 	kauth_listen_scope(OVERLAY_ISCOPE_PROCESS,
108 	    secmodel_suser_process_cb, NULL);
109 	kauth_listen_scope(OVERLAY_ISCOPE_PROCESS,
110 	    secmodel_securelevel_process_cb, NULL);
111 
112 	kauth_listen_scope(OVERLAY_ISCOPE_NETWORK,
113 	    secmodel_suser_network_cb, NULL);
114 	kauth_listen_scope(OVERLAY_ISCOPE_NETWORK,
115 	    secmodel_securelevel_network_cb, NULL);
116 
117 	kauth_listen_scope(OVERLAY_ISCOPE_MACHDEP,
118 	    secmodel_suser_machdep_cb, NULL);
119 	kauth_listen_scope(OVERLAY_ISCOPE_MACHDEP,
120 	    secmodel_securelevel_machdep_cb, NULL);
121 
122 	kauth_listen_scope(OVERLAY_ISCOPE_DEVICE,
123 	    secmodel_suser_device_cb, NULL);
124 	kauth_listen_scope(OVERLAY_ISCOPE_DEVICE,
125 	    secmodel_securelevel_device_cb, NULL);
126 
127 	secmodel_bsd44_init();
128 }
129 
130 void
131 sysctl_security_overlay_setup(struct sysctllog **clog)
132 {
133 	const struct sysctlnode *rnode;
134 
135 	sysctl_createv(clog, 0, NULL, &rnode,
136 		       CTLFLAG_PERMANENT,
137 		       CTLTYPE_NODE, "security", NULL,
138 		       NULL, 0, NULL, 0,
139 		       CTL_SECURITY, CTL_EOL);
140 
141 	sysctl_createv(clog, 0, &rnode, &rnode,
142 		       CTLFLAG_PERMANENT,
143 		       CTLTYPE_NODE, "models", NULL,
144 		       NULL, 0, NULL, 0,
145 		       CTL_CREATE, CTL_EOL);
146 
147 	sysctl_createv(clog, 0, &rnode, &rnode,
148 		       CTLFLAG_PERMANENT,
149 		       CTLTYPE_NODE, "overlay",
150 		       SYSCTL_DESCR("Overlay security model on-top of bsd44, "),
151 		       NULL, 0, NULL, 0,
152 		       CTL_CREATE, CTL_EOL);
153 
154 	sysctl_createv(clog, 0, &rnode, NULL,
155 		       CTLFLAG_PERMANENT,
156 		       CTLTYPE_STRING, "name", NULL,
157 		       NULL, 0, __UNCONST("Overlay (on-top of bsd44)"), 0,
158 		       CTL_CREATE, CTL_EOL);
159 }
160 
161 /*
162  * Start the overlay security model.
163  */
164 void
165 secmodel_overlay_start(void)
166 {
167 	l_generic = kauth_listen_scope(KAUTH_SCOPE_GENERIC,
168 	    secmodel_overlay_generic_cb, NULL);
169 	l_system = kauth_listen_scope(KAUTH_SCOPE_SYSTEM,
170 	    secmodel_overlay_system_cb, NULL);
171 	l_process = kauth_listen_scope(KAUTH_SCOPE_PROCESS,
172 	    secmodel_overlay_process_cb, NULL);
173 	l_network = kauth_listen_scope(KAUTH_SCOPE_NETWORK,
174 	    secmodel_overlay_network_cb, NULL);
175 	l_machdep = kauth_listen_scope(KAUTH_SCOPE_MACHDEP,
176 	    secmodel_overlay_machdep_cb, NULL);
177 	l_device = kauth_listen_scope(KAUTH_SCOPE_DEVICE,
178 	    secmodel_overlay_device_cb, NULL);
179 	l_vnode = kauth_listen_scope(KAUTH_SCOPE_VNODE,
180 	    secmodel_overlay_vnode_cb, NULL);
181 
182 	/* secmodel_register(); */
183 }
184 
185 /*
186  * Stop the overlay security model.
187  */
188 void
189 secmodel_overlay_stop(void)
190 {
191 	kauth_unlisten_scope(l_generic);
192 	kauth_unlisten_scope(l_system);
193 	kauth_unlisten_scope(l_process);
194 	kauth_unlisten_scope(l_network);
195 	kauth_unlisten_scope(l_machdep);
196 	kauth_unlisten_scope(l_device);
197 	kauth_unlisten_scope(l_vnode);
198 }
199 
200 static int
201 secmodel_overlay_modcmd(modcmd_t cmd, void *arg)
202 {
203 	int error = 0;
204 
205 	switch (cmd) {
206 	case MODULE_CMD_INIT:
207 		secmodel_overlay_init();
208 		secmodel_bsd44_stop();
209 		secmodel_overlay_start();
210 		sysctl_security_overlay_setup(&sysctl_overlay_log);
211 		break;
212 
213 	case MODULE_CMD_FINI:
214 		sysctl_teardown(&sysctl_overlay_log);
215 		secmodel_overlay_stop();
216 		break;
217 
218 	case MODULE_CMD_AUTOUNLOAD:
219 		error = EPERM;
220 		break;
221 
222 	default:
223 		error = ENOTTY;
224 		break;
225 	}
226 
227 	return error;
228 }
229 
230 /*
231  * Overlay listener for the generic scope.
232  */
233 int
234 secmodel_overlay_generic_cb(kauth_cred_t cred, kauth_action_t action,
235     void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
236 {
237 	int result;
238 
239 	result = KAUTH_RESULT_DEFER;
240 
241 	switch (action) {
242 	default:
243 		result = KAUTH_RESULT_DEFER;
244 		break;
245 	}
246 
247 	if (result == KAUTH_RESULT_DEFER) {
248 		result = kauth_authorize_action(
249 		    secmodel_overlay_iscope_generic, cred, action,
250 		    arg0, arg1, arg2, arg3);
251 	}
252 
253 	return (result);
254 }
255 
256 /*
257  * Overlay listener for the system scope.
258  */
259 int
260 secmodel_overlay_system_cb(kauth_cred_t cred, kauth_action_t action,
261     void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
262 {
263 	int result;
264 
265 	result = KAUTH_RESULT_DEFER;
266 
267 	switch (action) {
268 	default:
269 		result = KAUTH_RESULT_DEFER;
270 		break;
271 	}
272 
273 	if (result == KAUTH_RESULT_DEFER) {
274 		result = kauth_authorize_action(
275 		    secmodel_overlay_iscope_system, cred, action,
276 		    arg0, arg1, arg2, arg3);
277 	}
278 
279 	return (result);
280 }
281 
282 /*
283  * Overlay listener for the process scope.
284  */
285 int
286 secmodel_overlay_process_cb(kauth_cred_t cred, kauth_action_t action,
287     void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
288 {
289 	int result;
290 
291 	result = KAUTH_RESULT_DEFER;
292 
293 	switch (action) {
294 	default:
295 		result = KAUTH_RESULT_DEFER;
296 		break;
297 	}
298 
299 	if (result == KAUTH_RESULT_DEFER) {
300 		result = kauth_authorize_action(
301 		    secmodel_overlay_iscope_process, cred, action,
302 		    arg0, arg1, arg2, arg3);
303 	}
304 
305 	return (result);
306 }
307 
308 /*
309  * Overlay listener for the network scope.
310  */
311 int
312 secmodel_overlay_network_cb(kauth_cred_t cred, kauth_action_t action,
313     void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
314 {
315 	int result;
316 
317 	result = KAUTH_RESULT_DEFER;
318 
319 	switch (action) {
320 	default:
321 		result = KAUTH_RESULT_DEFER;
322 		break;
323 	}
324 
325 	if (result == KAUTH_RESULT_DEFER) {
326 		result = kauth_authorize_action(
327 		    secmodel_overlay_iscope_network, cred, action,
328 		    arg0, arg1, arg2, arg3);
329 	}
330 
331 	return (result);
332 }
333 
334 /*
335  * Overlay listener for the machdep scope.
336  */
337 int
338 secmodel_overlay_machdep_cb(kauth_cred_t cred, kauth_action_t action,
339     void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
340 {
341 	int result;
342 
343 	result = KAUTH_RESULT_DEFER;
344 
345 	switch (action) {
346 	default:
347 		result = KAUTH_RESULT_DEFER;
348 		break;
349 	}
350 
351 	if (result == KAUTH_RESULT_DEFER) {
352 		result = kauth_authorize_action(
353 		    secmodel_overlay_iscope_machdep, cred, action,
354 		    arg0, arg1, arg2, arg3);
355 	}
356 
357 	return (result);
358 }
359 
360 /*
361  * Overlay listener for the device scope.
362  */
363 int
364 secmodel_overlay_device_cb(kauth_cred_t cred, kauth_action_t action,
365     void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
366 {
367 	int result;
368 
369 	result = KAUTH_RESULT_DEFER;
370 
371 	switch (action) {
372 	default:
373 		result = KAUTH_RESULT_DEFER;
374 		break;
375 	}
376 
377 	if (result == KAUTH_RESULT_DEFER) {
378 		result = kauth_authorize_action(
379 		    secmodel_overlay_iscope_device, cred, action,
380 		    arg0, arg1, arg2, arg3);
381 	}
382 
383 	return (result);
384 }
385 
386 /*
387  * Overlay listener for the vnode scope.
388  */
389 int
390 secmodel_overlay_vnode_cb(kauth_cred_t cred, kauth_action_t action,
391     void *cookie, void *arg0, void *arg1, void *arg2, void *arg3)
392 {
393 	int result;
394 
395 	result = KAUTH_RESULT_DEFER;
396 
397 	switch (action) {
398 	default:
399 		result = KAUTH_RESULT_DEFER;
400 		break;
401 	}
402 
403 	if (result == KAUTH_RESULT_DEFER) {
404 		result = kauth_authorize_action(
405 		    secmodel_overlay_iscope_vnode, cred, action,
406 		    arg0, arg1, arg2, arg3);
407 	}
408 
409 	return (result);
410 }
411