xref: /freebsd/sys/security/mac/mac_inet.c (revision fc1f75e512df3ae08ea50c496cd6c7e89780b201)
1 /*-
2  * Copyright (c) 1999-2002, 2007, 2009 Robert N. M. Watson
3  * Copyright (c) 2001 Ilmar S. Habibulin
4  * Copyright (c) 2001-2004 Networks Associates Technology, Inc.
5  * Copyright (c) 2006 SPARTA, Inc.
6  * Copyright (c) 2008 Apple Inc.
7  * All rights reserved.
8  *
9  * This software was developed by Robert Watson and Ilmar Habibulin for the
10  * TrustedBSD Project.
11  *
12  * This software was developed for the FreeBSD Project in part by Network
13  * Associates Laboratories, the Security Research Division of Network
14  * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
15  * as part of the DARPA CHATS research program.
16  *
17  * This software was enhanced by SPARTA ISSO under SPAWAR contract
18  * N66001-04-C-6019 ("SEFOS").
19  *
20  * This software was developed at the University of Cambridge Computer
21  * Laboratory with support from a grant from Google, Inc.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the above copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  *
32  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
33  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
34  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
35  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
36  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
40  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
41  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
42  * SUCH DAMAGE.
43  */
44 
45 #include <sys/cdefs.h>
46 __FBSDID("$FreeBSD$");
47 
48 #include "opt_kdtrace.h"
49 #include "opt_mac.h"
50 
51 #include <sys/param.h>
52 #include <sys/kernel.h>
53 #include <sys/lock.h>
54 #include <sys/malloc.h>
55 #include <sys/mutex.h>
56 #include <sys/sbuf.h>
57 #include <sys/sdt.h>
58 #include <sys/systm.h>
59 #include <sys/mount.h>
60 #include <sys/file.h>
61 #include <sys/namei.h>
62 #include <sys/protosw.h>
63 #include <sys/socket.h>
64 #include <sys/socketvar.h>
65 #include <sys/sysctl.h>
66 
67 #include <net/if.h>
68 #include <net/if_var.h>
69 
70 #include <netinet/in.h>
71 #include <netinet/in_pcb.h>
72 #include <netinet/ip_var.h>
73 
74 #include <security/mac/mac_framework.h>
75 #include <security/mac/mac_internal.h>
76 #include <security/mac/mac_policy.h>
77 
78 static struct label *
79 mac_inpcb_label_alloc(int flag)
80 {
81 	struct label *label;
82 	int error;
83 
84 	label = mac_labelzone_alloc(flag);
85 	if (label == NULL)
86 		return (NULL);
87 	MAC_CHECK(inpcb_init_label, label, flag);
88 	if (error) {
89 		MAC_PERFORM(inpcb_destroy_label, label);
90 		mac_labelzone_free(label);
91 		return (NULL);
92 	}
93 	return (label);
94 }
95 
96 int
97 mac_inpcb_init(struct inpcb *inp, int flag)
98 {
99 
100 	if (mac_labeled & MPC_OBJECT_INPCB) {
101 		inp->inp_label = mac_inpcb_label_alloc(flag);
102 		if (inp->inp_label == NULL)
103 			return (ENOMEM);
104 	} else
105 		inp->inp_label = NULL;
106 	return (0);
107 }
108 
109 static struct label *
110 mac_ipq_label_alloc(int flag)
111 {
112 	struct label *label;
113 	int error;
114 
115 	label = mac_labelzone_alloc(flag);
116 	if (label == NULL)
117 		return (NULL);
118 
119 	MAC_CHECK(ipq_init_label, label, flag);
120 	if (error) {
121 		MAC_PERFORM(ipq_destroy_label, label);
122 		mac_labelzone_free(label);
123 		return (NULL);
124 	}
125 	return (label);
126 }
127 
128 int
129 mac_ipq_init(struct ipq *q, int flag)
130 {
131 
132 	if (mac_labeled & MPC_OBJECT_IPQ) {
133 		q->ipq_label = mac_ipq_label_alloc(flag);
134 		if (q->ipq_label == NULL)
135 			return (ENOMEM);
136 	} else
137 		q->ipq_label = NULL;
138 	return (0);
139 }
140 
141 static void
142 mac_inpcb_label_free(struct label *label)
143 {
144 
145 	MAC_PERFORM(inpcb_destroy_label, label);
146 	mac_labelzone_free(label);
147 }
148 
149 void
150 mac_inpcb_destroy(struct inpcb *inp)
151 {
152 
153 	if (inp->inp_label != NULL) {
154 		mac_inpcb_label_free(inp->inp_label);
155 		inp->inp_label = NULL;
156 	}
157 }
158 
159 static void
160 mac_ipq_label_free(struct label *label)
161 {
162 
163 	MAC_PERFORM(ipq_destroy_label, label);
164 	mac_labelzone_free(label);
165 }
166 
167 void
168 mac_ipq_destroy(struct ipq *q)
169 {
170 
171 	if (q->ipq_label != NULL) {
172 		mac_ipq_label_free(q->ipq_label);
173 		q->ipq_label = NULL;
174 	}
175 }
176 
177 void
178 mac_inpcb_create(struct socket *so, struct inpcb *inp)
179 {
180 
181 	MAC_PERFORM(inpcb_create, so, so->so_label, inp, inp->inp_label);
182 }
183 
184 void
185 mac_ipq_reassemble(struct ipq *q, struct mbuf *m)
186 {
187 	struct label *label;
188 
189 	label = mac_mbuf_to_label(m);
190 
191 	MAC_PERFORM(ipq_reassemble, q, q->ipq_label, m, label);
192 }
193 
194 void
195 mac_netinet_fragment(struct mbuf *m, struct mbuf *frag)
196 {
197 	struct label *mlabel, *fraglabel;
198 
199 	mlabel = mac_mbuf_to_label(m);
200 	fraglabel = mac_mbuf_to_label(frag);
201 
202 	MAC_PERFORM(netinet_fragment, m, mlabel, frag, fraglabel);
203 }
204 
205 void
206 mac_ipq_create(struct mbuf *m, struct ipq *q)
207 {
208 	struct label *label;
209 
210 	label = mac_mbuf_to_label(m);
211 
212 	MAC_PERFORM(ipq_create, m, label, q, q->ipq_label);
213 }
214 
215 void
216 mac_inpcb_create_mbuf(struct inpcb *inp, struct mbuf *m)
217 {
218 	struct label *mlabel;
219 
220 	INP_LOCK_ASSERT(inp);
221 	mlabel = mac_mbuf_to_label(m);
222 
223 	MAC_PERFORM(inpcb_create_mbuf, inp, inp->inp_label, m, mlabel);
224 }
225 
226 int
227 mac_ipq_match(struct mbuf *m, struct ipq *q)
228 {
229 	struct label *label;
230 	int result;
231 
232 	label = mac_mbuf_to_label(m);
233 
234 	result = 1;
235 	MAC_BOOLEAN(ipq_match, &&, m, label, q, q->ipq_label);
236 
237 	return (result);
238 }
239 
240 void
241 mac_netinet_arp_send(struct ifnet *ifp, struct mbuf *m)
242 {
243 	struct label *mlabel;
244 
245 	mlabel = mac_mbuf_to_label(m);
246 
247 	MAC_IFNET_LOCK(ifp);
248 	MAC_PERFORM(netinet_arp_send, ifp, ifp->if_label, m, mlabel);
249 	MAC_IFNET_UNLOCK(ifp);
250 }
251 
252 void
253 mac_netinet_icmp_reply(struct mbuf *mrecv, struct mbuf *msend)
254 {
255 	struct label *mrecvlabel, *msendlabel;
256 
257 	mrecvlabel = mac_mbuf_to_label(mrecv);
258 	msendlabel = mac_mbuf_to_label(msend);
259 
260 	MAC_PERFORM(netinet_icmp_reply, mrecv, mrecvlabel, msend,
261 	    msendlabel);
262 }
263 
264 void
265 mac_netinet_icmp_replyinplace(struct mbuf *m)
266 {
267 	struct label *label;
268 
269 	label = mac_mbuf_to_label(m);
270 
271 	MAC_PERFORM(netinet_icmp_replyinplace, m, label);
272 }
273 
274 void
275 mac_netinet_igmp_send(struct ifnet *ifp, struct mbuf *m)
276 {
277 	struct label *mlabel;
278 
279 	mlabel = mac_mbuf_to_label(m);
280 
281 	MAC_IFNET_LOCK(ifp);
282 	MAC_PERFORM(netinet_igmp_send, ifp, ifp->if_label, m, mlabel);
283 	MAC_IFNET_UNLOCK(ifp);
284 }
285 
286 void
287 mac_netinet_tcp_reply(struct mbuf *m)
288 {
289 	struct label *label;
290 
291 	label = mac_mbuf_to_label(m);
292 
293 	MAC_PERFORM(netinet_tcp_reply, m, label);
294 }
295 
296 void
297 mac_ipq_update(struct mbuf *m, struct ipq *q)
298 {
299 	struct label *label;
300 
301 	label = mac_mbuf_to_label(m);
302 
303 	MAC_PERFORM(ipq_update, m, label, q, q->ipq_label);
304 }
305 
306 MAC_CHECK_PROBE_DEFINE2(inpcb_check_deliver, "struct inpcb *",
307     "struct mbuf *");
308 
309 int
310 mac_inpcb_check_deliver(struct inpcb *inp, struct mbuf *m)
311 {
312 	struct label *label;
313 	int error;
314 
315 	M_ASSERTPKTHDR(m);
316 
317 	label = mac_mbuf_to_label(m);
318 
319 	MAC_CHECK(inpcb_check_deliver, inp, inp->inp_label, m, label);
320 	MAC_CHECK_PROBE2(inpcb_check_deliver, error, inp, m);
321 
322 	return (error);
323 }
324 
325 MAC_CHECK_PROBE_DEFINE2(inpcb_check_visible, "struct ucred *",
326     "struct inpcb *");
327 
328 int
329 mac_inpcb_check_visible(struct ucred *cred, struct inpcb *inp)
330 {
331 	int error;
332 
333 	INP_LOCK_ASSERT(inp);
334 
335 	MAC_CHECK(inpcb_check_visible, cred, inp, inp->inp_label);
336 	MAC_CHECK_PROBE2(inpcb_check_visible, error, cred, inp);
337 
338 	return (error);
339 }
340 
341 void
342 mac_inpcb_sosetlabel(struct socket *so, struct inpcb *inp)
343 {
344 
345 	INP_WLOCK_ASSERT(inp);
346 	SOCK_LOCK_ASSERT(so);
347 	MAC_PERFORM(inpcb_sosetlabel, so, so->so_label, inp, inp->inp_label);
348 }
349 
350 void
351 mac_netinet_firewall_reply(struct mbuf *mrecv, struct mbuf *msend)
352 {
353 	struct label *mrecvlabel, *msendlabel;
354 
355 	M_ASSERTPKTHDR(mrecv);
356 	M_ASSERTPKTHDR(msend);
357 
358 	mrecvlabel = mac_mbuf_to_label(mrecv);
359 	msendlabel = mac_mbuf_to_label(msend);
360 
361 	MAC_PERFORM(netinet_firewall_reply, mrecv, mrecvlabel, msend,
362 	    msendlabel);
363 }
364 
365 void
366 mac_netinet_firewall_send(struct mbuf *m)
367 {
368 	struct label *label;
369 
370 	M_ASSERTPKTHDR(m);
371 	label = mac_mbuf_to_label(m);
372 	MAC_PERFORM(netinet_firewall_send, m, label);
373 }
374 
375 /*
376  * These functions really should be referencing the syncache structure
377  * instead of the label.  However, due to some of the complexities associated
378  * with exposing this syncache structure we operate directly on it's label
379  * pointer.  This should be OK since we aren't making any access control
380  * decisions within this code directly, we are merely allocating and copying
381  * label storage so we can properly initialize mbuf labels for any packets
382  * the syncache code might create.
383  */
384 void
385 mac_syncache_destroy(struct label **label)
386 {
387 
388 	if (*label != NULL) {
389 		MAC_PERFORM(syncache_destroy_label, *label);
390 		mac_labelzone_free(*label);
391 		*label = NULL;
392 	}
393 }
394 
395 int
396 mac_syncache_init(struct label **label)
397 {
398 	int error;
399 
400 	if (mac_labeled & MPC_OBJECT_SYNCACHE) {
401 		*label = mac_labelzone_alloc(M_NOWAIT);
402 		if (*label == NULL)
403 			return (ENOMEM);
404 		/*
405 		 * Since we are holding the inpcb locks the policy can not
406 		 * allocate policy specific label storage using M_WAITOK.  So
407 		 * we need to do a MAC_CHECK instead of the typical
408 		 * MAC_PERFORM so we can propagate allocation failures back
409 		 * to the syncache code.
410 		 */
411 		MAC_CHECK(syncache_init_label, *label, M_NOWAIT);
412 		if (error) {
413 			MAC_PERFORM(syncache_destroy_label, *label);
414 			mac_labelzone_free(*label);
415 		}
416 		return (error);
417 	} else
418 		*label = NULL;
419 	return (0);
420 }
421 
422 void
423 mac_syncache_create(struct label *label, struct inpcb *inp)
424 {
425 
426 	INP_WLOCK_ASSERT(inp);
427 	MAC_PERFORM(syncache_create, label, inp);
428 }
429 
430 void
431 mac_syncache_create_mbuf(struct label *sc_label, struct mbuf *m)
432 {
433 	struct label *mlabel;
434 
435 	M_ASSERTPKTHDR(m);
436 	mlabel = mac_mbuf_to_label(m);
437 	MAC_PERFORM(syncache_create_mbuf, sc_label, m, mlabel);
438 }
439