xref: /freebsd-13-stable/sys/security/mac/mac_inet.c (revision c7e7794e954604048ecfe9468237b2bb3d95bd1c)
1 /*-
2  * Copyright (c) 1999-2002, 2007, 2009, 2019 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 #include "opt_mac.h"
47 
48 #include <sys/param.h>
49 #include <sys/kernel.h>
50 #include <sys/lock.h>
51 #include <sys/malloc.h>
52 #include <sys/mutex.h>
53 #include <sys/sbuf.h>
54 #include <sys/sdt.h>
55 #include <sys/systm.h>
56 #include <sys/mount.h>
57 #include <sys/file.h>
58 #include <sys/namei.h>
59 #include <sys/protosw.h>
60 #include <sys/socket.h>
61 #include <sys/socketvar.h>
62 #include <sys/sysctl.h>
63 
64 #include <net/if.h>
65 #include <net/if_var.h>
66 
67 #include <netinet/in.h>
68 #include <netinet/in_pcb.h>
69 #include <netinet/ip_var.h>
70 
71 #include <security/mac/mac_framework.h>
72 #include <security/mac/mac_internal.h>
73 #include <security/mac/mac_policy.h>
74 
75 static struct label *
mac_inpcb_label_alloc(int flag)76 mac_inpcb_label_alloc(int flag)
77 {
78 	struct label *label;
79 	int error;
80 
81 	label = mac_labelzone_alloc(flag);
82 	if (label == NULL)
83 		return (NULL);
84 	if (flag & M_WAITOK)
85 		MAC_POLICY_CHECK(inpcb_init_label, label, flag);
86 	else
87 		MAC_POLICY_CHECK_NOSLEEP(inpcb_init_label, label, flag);
88 	if (error) {
89 		MAC_POLICY_PERFORM_NOSLEEP(inpcb_destroy_label, label);
90 		mac_labelzone_free(label);
91 		return (NULL);
92 	}
93 	return (label);
94 }
95 
96 int
mac_inpcb_init(struct inpcb * inp,int flag)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 *
mac_ipq_label_alloc(int flag)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 	if (flag & M_WAITOK)
120 		MAC_POLICY_CHECK(ipq_init_label, label, flag);
121 	else
122 		MAC_POLICY_CHECK_NOSLEEP(ipq_init_label, label, flag);
123 	if (error) {
124 		MAC_POLICY_PERFORM_NOSLEEP(ipq_destroy_label, label);
125 		mac_labelzone_free(label);
126 		return (NULL);
127 	}
128 	return (label);
129 }
130 
131 int
mac_ipq_init(struct ipq * q,int flag)132 mac_ipq_init(struct ipq *q, int flag)
133 {
134 
135 	if (mac_labeled & MPC_OBJECT_IPQ) {
136 		q->ipq_label = mac_ipq_label_alloc(flag);
137 		if (q->ipq_label == NULL)
138 			return (ENOMEM);
139 	} else
140 		q->ipq_label = NULL;
141 	return (0);
142 }
143 
144 static void
mac_inpcb_label_free(struct label * label)145 mac_inpcb_label_free(struct label *label)
146 {
147 
148 	MAC_POLICY_PERFORM_NOSLEEP(inpcb_destroy_label, label);
149 	mac_labelzone_free(label);
150 }
151 
152 void
mac_inpcb_destroy(struct inpcb * inp)153 mac_inpcb_destroy(struct inpcb *inp)
154 {
155 
156 	if (inp->inp_label != NULL) {
157 		mac_inpcb_label_free(inp->inp_label);
158 		inp->inp_label = NULL;
159 	}
160 }
161 
162 static void
mac_ipq_label_free(struct label * label)163 mac_ipq_label_free(struct label *label)
164 {
165 
166 	MAC_POLICY_PERFORM_NOSLEEP(ipq_destroy_label, label);
167 	mac_labelzone_free(label);
168 }
169 
170 void
mac_ipq_destroy(struct ipq * q)171 mac_ipq_destroy(struct ipq *q)
172 {
173 
174 	if (q->ipq_label != NULL) {
175 		mac_ipq_label_free(q->ipq_label);
176 		q->ipq_label = NULL;
177 	}
178 }
179 
180 void
mac_inpcb_create(struct socket * so,struct inpcb * inp)181 mac_inpcb_create(struct socket *so, struct inpcb *inp)
182 {
183 
184 	MAC_POLICY_PERFORM_NOSLEEP(inpcb_create, so, so->so_label, inp,
185 	    inp->inp_label);
186 }
187 
188 void
mac_ipq_reassemble(struct ipq * q,struct mbuf * m)189 mac_ipq_reassemble(struct ipq *q, struct mbuf *m)
190 {
191 	struct label *label;
192 
193 	if (mac_policy_count == 0)
194 		return;
195 
196 	label = mac_mbuf_to_label(m);
197 
198 	MAC_POLICY_PERFORM_NOSLEEP(ipq_reassemble, q, q->ipq_label, m,
199 	    label);
200 }
201 
202 void
mac_netinet_fragment(struct mbuf * m,struct mbuf * frag)203 mac_netinet_fragment(struct mbuf *m, struct mbuf *frag)
204 {
205 	struct label *mlabel, *fraglabel;
206 
207 	if (mac_policy_count == 0)
208 		return;
209 
210 	mlabel = mac_mbuf_to_label(m);
211 	fraglabel = mac_mbuf_to_label(frag);
212 
213 	MAC_POLICY_PERFORM_NOSLEEP(netinet_fragment, m, mlabel, frag,
214 	    fraglabel);
215 }
216 
217 void
mac_ipq_create(struct mbuf * m,struct ipq * q)218 mac_ipq_create(struct mbuf *m, struct ipq *q)
219 {
220 	struct label *label;
221 
222 	if (mac_policy_count == 0)
223 		return;
224 
225 	label = mac_mbuf_to_label(m);
226 
227 	MAC_POLICY_PERFORM_NOSLEEP(ipq_create, m, label, q, q->ipq_label);
228 }
229 
230 void
mac_inpcb_create_mbuf(struct inpcb * inp,struct mbuf * m)231 mac_inpcb_create_mbuf(struct inpcb *inp, struct mbuf *m)
232 {
233 	struct label *mlabel;
234 
235 	INP_LOCK_ASSERT(inp);
236 
237 	if (mac_policy_count == 0)
238 		return;
239 
240 	mlabel = mac_mbuf_to_label(m);
241 
242 	MAC_POLICY_PERFORM_NOSLEEP(inpcb_create_mbuf, inp, inp->inp_label, m,
243 	    mlabel);
244 }
245 
246 int
mac_ipq_match(struct mbuf * m,struct ipq * q)247 mac_ipq_match(struct mbuf *m, struct ipq *q)
248 {
249 	struct label *label;
250 	int result;
251 
252 	if (mac_policy_count == 0)
253 		return (1);
254 
255 	label = mac_mbuf_to_label(m);
256 
257 	result = 1;
258 	MAC_POLICY_BOOLEAN_NOSLEEP(ipq_match, &&, m, label, q, q->ipq_label);
259 
260 	return (result);
261 }
262 
263 void
mac_netinet_arp_send(struct ifnet * ifp,struct mbuf * m)264 mac_netinet_arp_send(struct ifnet *ifp, struct mbuf *m)
265 {
266 	struct label *mlabel;
267 	int locked;
268 
269 	if (mac_policy_count == 0)
270 		return;
271 
272 	mlabel = mac_mbuf_to_label(m);
273 
274 	MAC_IFNET_LOCK(ifp, locked);
275 	MAC_POLICY_PERFORM_NOSLEEP(netinet_arp_send, ifp, ifp->if_label, m,
276 	    mlabel);
277 	MAC_IFNET_UNLOCK(ifp, locked);
278 }
279 
280 void
mac_netinet_icmp_reply(struct mbuf * mrecv,struct mbuf * msend)281 mac_netinet_icmp_reply(struct mbuf *mrecv, struct mbuf *msend)
282 {
283 	struct label *mrecvlabel, *msendlabel;
284 
285 	if (mac_policy_count == 0)
286 		return;
287 
288 	mrecvlabel = mac_mbuf_to_label(mrecv);
289 	msendlabel = mac_mbuf_to_label(msend);
290 
291 	MAC_POLICY_PERFORM_NOSLEEP(netinet_icmp_reply, mrecv, mrecvlabel,
292 	    msend, msendlabel);
293 }
294 
295 void
mac_netinet_icmp_replyinplace(struct mbuf * m)296 mac_netinet_icmp_replyinplace(struct mbuf *m)
297 {
298 	struct label *label;
299 
300 	if (mac_policy_count == 0)
301 		return;
302 
303 	label = mac_mbuf_to_label(m);
304 
305 	MAC_POLICY_PERFORM_NOSLEEP(netinet_icmp_replyinplace, m, label);
306 }
307 
308 void
mac_netinet_igmp_send(struct ifnet * ifp,struct mbuf * m)309 mac_netinet_igmp_send(struct ifnet *ifp, struct mbuf *m)
310 {
311 	struct label *mlabel;
312 	int locked;
313 
314 	if (mac_policy_count == 0)
315 		return;
316 
317 	mlabel = mac_mbuf_to_label(m);
318 
319 	MAC_IFNET_LOCK(ifp, locked);
320 	MAC_POLICY_PERFORM_NOSLEEP(netinet_igmp_send, ifp, ifp->if_label, m,
321 	    mlabel);
322 	MAC_IFNET_UNLOCK(ifp, locked);
323 }
324 
325 void
mac_netinet_tcp_reply(struct mbuf * m)326 mac_netinet_tcp_reply(struct mbuf *m)
327 {
328 	struct label *label;
329 
330 	if (mac_policy_count == 0)
331 		return;
332 
333 	label = mac_mbuf_to_label(m);
334 
335 	MAC_POLICY_PERFORM_NOSLEEP(netinet_tcp_reply, m, label);
336 }
337 
338 void
mac_ipq_update(struct mbuf * m,struct ipq * q)339 mac_ipq_update(struct mbuf *m, struct ipq *q)
340 {
341 	struct label *label;
342 
343 	if (mac_policy_count == 0)
344 		return;
345 
346 	label = mac_mbuf_to_label(m);
347 
348 	MAC_POLICY_PERFORM_NOSLEEP(ipq_update, m, label, q, q->ipq_label);
349 }
350 
351 MAC_CHECK_PROBE_DEFINE2(inpcb_check_deliver, "struct inpcb *",
352     "struct mbuf *");
353 
354 int
mac_inpcb_check_deliver(struct inpcb * inp,struct mbuf * m)355 mac_inpcb_check_deliver(struct inpcb *inp, struct mbuf *m)
356 {
357 	struct label *label;
358 	int error;
359 
360 	M_ASSERTPKTHDR(m);
361 
362 	if (mac_policy_count == 0)
363 		return (0);
364 
365 	label = mac_mbuf_to_label(m);
366 
367 	MAC_POLICY_CHECK_NOSLEEP(inpcb_check_deliver, inp, inp->inp_label, m,
368 	    label);
369 	MAC_CHECK_PROBE2(inpcb_check_deliver, error, inp, m);
370 
371 	return (error);
372 }
373 
374 MAC_CHECK_PROBE_DEFINE2(inpcb_check_visible, "struct ucred *",
375     "struct inpcb *");
376 
377 int
mac_inpcb_check_visible(struct ucred * cred,struct inpcb * inp)378 mac_inpcb_check_visible(struct ucred *cred, struct inpcb *inp)
379 {
380 	int error;
381 
382 	INP_LOCK_ASSERT(inp);
383 
384 	MAC_POLICY_CHECK_NOSLEEP(inpcb_check_visible, cred, inp,
385 	    inp->inp_label);
386 	MAC_CHECK_PROBE2(inpcb_check_visible, error, cred, inp);
387 
388 	return (error);
389 }
390 
391 void
mac_inpcb_sosetlabel(struct socket * so,struct inpcb * inp)392 mac_inpcb_sosetlabel(struct socket *so, struct inpcb *inp)
393 {
394 
395 	INP_WLOCK_ASSERT(inp);
396 	SOCK_LOCK_ASSERT(so);
397 
398 	MAC_POLICY_PERFORM_NOSLEEP(inpcb_sosetlabel, so, so->so_label, inp,
399 	    inp->inp_label);
400 }
401 
402 void
mac_netinet_firewall_reply(struct mbuf * mrecv,struct mbuf * msend)403 mac_netinet_firewall_reply(struct mbuf *mrecv, struct mbuf *msend)
404 {
405 	struct label *mrecvlabel, *msendlabel;
406 
407 	M_ASSERTPKTHDR(mrecv);
408 	M_ASSERTPKTHDR(msend);
409 
410 	if (mac_policy_count == 0)
411 		return;
412 
413 	mrecvlabel = mac_mbuf_to_label(mrecv);
414 	msendlabel = mac_mbuf_to_label(msend);
415 
416 	MAC_POLICY_PERFORM_NOSLEEP(netinet_firewall_reply, mrecv, mrecvlabel,
417 	    msend, msendlabel);
418 }
419 
420 void
mac_netinet_firewall_send(struct mbuf * m)421 mac_netinet_firewall_send(struct mbuf *m)
422 {
423 	struct label *label;
424 
425 	M_ASSERTPKTHDR(m);
426 
427 	if (mac_policy_count == 0)
428 		return;
429 
430 	label = mac_mbuf_to_label(m);
431 
432 	MAC_POLICY_PERFORM_NOSLEEP(netinet_firewall_send, m, label);
433 }
434 
435 /*
436  * These functions really should be referencing the syncache structure
437  * instead of the label.  However, due to some of the complexities associated
438  * with exposing this syncache structure we operate directly on its label
439  * pointer.  This should be OK since we aren't making any access control
440  * decisions within this code directly, we are merely allocating and copying
441  * label storage so we can properly initialize mbuf labels for any packets
442  * the syncache code might create.
443  */
444 void
mac_syncache_destroy(struct label ** label)445 mac_syncache_destroy(struct label **label)
446 {
447 
448 	if (*label != NULL) {
449 		MAC_POLICY_PERFORM_NOSLEEP(syncache_destroy_label, *label);
450 		mac_labelzone_free(*label);
451 		*label = NULL;
452 	}
453 }
454 
455 int
mac_syncache_init(struct label ** label)456 mac_syncache_init(struct label **label)
457 {
458 	int error;
459 
460 	if (mac_labeled & MPC_OBJECT_SYNCACHE) {
461 		*label = mac_labelzone_alloc(M_NOWAIT);
462 		if (*label == NULL)
463 			return (ENOMEM);
464 		/*
465 		 * Since we are holding the inpcb locks the policy can not
466 		 * allocate policy specific label storage using M_WAITOK.  So
467 		 * we need to do a MAC_CHECK instead of the typical
468 		 * MAC_PERFORM so we can propagate allocation failures back
469 		 * to the syncache code.
470 		 */
471 		MAC_POLICY_CHECK_NOSLEEP(syncache_init_label, *label,
472 		    M_NOWAIT);
473 		if (error) {
474 			MAC_POLICY_PERFORM_NOSLEEP(syncache_destroy_label,
475 			    *label);
476 			mac_labelzone_free(*label);
477 			*label = NULL;
478 		}
479 		return (error);
480 	} else
481 		*label = NULL;
482 	return (0);
483 }
484 
485 void
mac_syncache_create(struct label * label,struct inpcb * inp)486 mac_syncache_create(struct label *label, struct inpcb *inp)
487 {
488 
489 	INP_WLOCK_ASSERT(inp);
490 
491 	MAC_POLICY_PERFORM_NOSLEEP(syncache_create, label, inp);
492 }
493 
494 void
mac_syncache_create_mbuf(struct label * sc_label,struct mbuf * m)495 mac_syncache_create_mbuf(struct label *sc_label, struct mbuf *m)
496 {
497 	struct label *mlabel;
498 
499 	M_ASSERTPKTHDR(m);
500 
501 	if (mac_policy_count == 0)
502 		return;
503 
504 	mlabel = mac_mbuf_to_label(m);
505 
506 	MAC_POLICY_PERFORM_NOSLEEP(syncache_create_mbuf, sc_label, m,
507 	    mlabel);
508 }
509