xref: /freebsd/sys/security/mac/mac_pipe.c (revision 6b3455a7665208c366849f0b2b3bc916fb97516e)
1 /*-
2  * Copyright (c) 2002, 2003 Networks Associates Technology, Inc.
3  * All rights reserved.
4  *
5  * This software was developed for the FreeBSD Project in part by Network
6  * Associates Laboratories, the Security Research Division of Network
7  * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
8  * as part of the DARPA CHATS research program.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include "opt_mac.h"
36 
37 #include <sys/param.h>
38 #include <sys/kernel.h>
39 #include <sys/lock.h>
40 #include <sys/malloc.h>
41 #include <sys/module.h>
42 #include <sys/mutex.h>
43 #include <sys/mac.h>
44 #include <sys/sbuf.h>
45 #include <sys/systm.h>
46 #include <sys/vnode.h>
47 #include <sys/pipe.h>
48 #include <sys/sysctl.h>
49 
50 #include <sys/mac_policy.h>
51 
52 #include <security/mac/mac_internal.h>
53 
54 static int	mac_enforce_pipe = 1;
55 SYSCTL_INT(_security_mac, OID_AUTO, enforce_pipe, CTLFLAG_RW,
56     &mac_enforce_pipe, 0, "Enforce MAC policy on pipe operations");
57 TUNABLE_INT("security.mac.enforce_pipe", &mac_enforce_pipe);
58 
59 #ifdef MAC_DEBUG
60 static unsigned int nmacpipes;
61 SYSCTL_UINT(_security_mac_debug_counters, OID_AUTO, pipes, CTLFLAG_RD,
62     &nmacpipes, 0, "number of pipes in use");
63 #endif
64 
65 struct label *
66 mac_pipe_label_alloc(void)
67 {
68 	struct label *label;
69 
70 	label = mac_labelzone_alloc(M_WAITOK);
71 	MAC_PERFORM(init_pipe_label, label);
72 	MAC_DEBUG_COUNTER_INC(&nmacpipes);
73 	return (label);
74 }
75 
76 void
77 mac_init_pipe(struct pipepair *pp)
78 {
79 
80 	pp->pp_label = mac_pipe_label_alloc();
81 }
82 
83 void
84 mac_pipe_label_free(struct label *label)
85 {
86 
87 	MAC_PERFORM(destroy_pipe_label, label);
88 	mac_labelzone_free(label);
89 	MAC_DEBUG_COUNTER_DEC(&nmacpipes);
90 }
91 
92 void
93 mac_destroy_pipe(struct pipepair *pp)
94 {
95 
96 	mac_pipe_label_free(pp->pp_label);
97 	pp->pp_label = NULL;
98 }
99 
100 void
101 mac_copy_pipe_label(struct label *src, struct label *dest)
102 {
103 
104 	MAC_PERFORM(copy_pipe_label, src, dest);
105 }
106 
107 int
108 mac_externalize_pipe_label(struct label *label, char *elements,
109     char *outbuf, size_t outbuflen)
110 {
111 	int error;
112 
113 	MAC_EXTERNALIZE(pipe, label, elements, outbuf, outbuflen);
114 
115 	return (error);
116 }
117 
118 int
119 mac_internalize_pipe_label(struct label *label, char *string)
120 {
121 	int error;
122 
123 	MAC_INTERNALIZE(pipe, label, string);
124 
125 	return (error);
126 }
127 
128 void
129 mac_create_pipe(struct ucred *cred, struct pipepair *pp)
130 {
131 
132 	MAC_PERFORM(create_pipe, cred, pp, pp->pp_label);
133 }
134 
135 static void
136 mac_relabel_pipe(struct ucred *cred, struct pipepair *pp,
137     struct label *newlabel)
138 {
139 
140 	MAC_PERFORM(relabel_pipe, cred, pp, pp->pp_label, newlabel);
141 }
142 
143 int
144 mac_check_pipe_ioctl(struct ucred *cred, struct pipepair *pp,
145     unsigned long cmd, void *data)
146 {
147 	int error;
148 
149 	mtx_assert(&pp->pp_mtx, MA_OWNED);
150 
151 	if (!mac_enforce_pipe)
152 		return (0);
153 
154 	MAC_CHECK(check_pipe_ioctl, cred, pp, pp->pp_label, cmd, data);
155 
156 	return (error);
157 }
158 
159 int
160 mac_check_pipe_poll(struct ucred *cred, struct pipepair *pp)
161 {
162 	int error;
163 
164 	mtx_assert(&pp->pp_mtx, MA_OWNED);
165 
166 	if (!mac_enforce_pipe)
167 		return (0);
168 
169 	MAC_CHECK(check_pipe_poll, cred, pp, pp->pp_label);
170 
171 	return (error);
172 }
173 
174 int
175 mac_check_pipe_read(struct ucred *cred, struct pipepair *pp)
176 {
177 	int error;
178 
179 	mtx_assert(&pp->pp_mtx, MA_OWNED);
180 
181 	if (!mac_enforce_pipe)
182 		return (0);
183 
184 	MAC_CHECK(check_pipe_read, cred, pp, pp->pp_label);
185 
186 	return (error);
187 }
188 
189 static int
190 mac_check_pipe_relabel(struct ucred *cred, struct pipepair *pp,
191     struct label *newlabel)
192 {
193 	int error;
194 
195 	mtx_assert(&pp->pp_mtx, MA_OWNED);
196 
197 	if (!mac_enforce_pipe)
198 		return (0);
199 
200 	MAC_CHECK(check_pipe_relabel, cred, pp, pp->pp_label, newlabel);
201 
202 	return (error);
203 }
204 
205 int
206 mac_check_pipe_stat(struct ucred *cred, struct pipepair *pp)
207 {
208 	int error;
209 
210 	mtx_assert(&pp->pp_mtx, MA_OWNED);
211 
212 	if (!mac_enforce_pipe)
213 		return (0);
214 
215 	MAC_CHECK(check_pipe_stat, cred, pp, pp->pp_label);
216 
217 	return (error);
218 }
219 
220 int
221 mac_check_pipe_write(struct ucred *cred, struct pipepair *pp)
222 {
223 	int error;
224 
225 	mtx_assert(&pp->pp_mtx, MA_OWNED);
226 
227 	if (!mac_enforce_pipe)
228 		return (0);
229 
230 	MAC_CHECK(check_pipe_write, cred, pp, pp->pp_label);
231 
232 	return (error);
233 }
234 
235 int
236 mac_pipe_label_set(struct ucred *cred, struct pipepair *pp,
237     struct label *label)
238 {
239 	int error;
240 
241 	mtx_assert(&pp->pp_mtx, MA_OWNED);
242 
243 	error = mac_check_pipe_relabel(cred, pp, label);
244 	if (error)
245 		return (error);
246 
247 	mac_relabel_pipe(cred, pp, label);
248 
249 	return (0);
250 }
251