xref: /freebsd/sys/security/mac/mac_pipe.c (revision 9608d7e2cd58c1a7fff6562810f2ce519e6ec50a)
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/mutex.h>
42 #include <sys/mac.h>
43 #include <sys/sbuf.h>
44 #include <sys/systm.h>
45 #include <sys/vnode.h>
46 #include <sys/pipe.h>
47 #include <sys/sysctl.h>
48 
49 #include <sys/mac_policy.h>
50 
51 #include <security/mac/mac_internal.h>
52 
53 static int	mac_enforce_pipe = 1;
54 SYSCTL_INT(_security_mac, OID_AUTO, enforce_pipe, CTLFLAG_RW,
55     &mac_enforce_pipe, 0, "Enforce MAC policy on pipe operations");
56 TUNABLE_INT("security.mac.enforce_pipe", &mac_enforce_pipe);
57 
58 #ifdef MAC_DEBUG
59 static unsigned int nmacpipes;
60 SYSCTL_UINT(_security_mac_debug_counters, OID_AUTO, pipes, CTLFLAG_RD,
61     &nmacpipes, 0, "number of pipes in use");
62 #endif
63 
64 struct label *
65 mac_pipe_label_alloc(void)
66 {
67 	struct label *label;
68 
69 	label = mac_labelzone_alloc(M_WAITOK);
70 	MAC_PERFORM(init_pipe_label, label);
71 	MAC_DEBUG_COUNTER_INC(&nmacpipes);
72 	return (label);
73 }
74 
75 void
76 mac_init_pipe(struct pipe *pipe)
77 {
78 
79 	pipe->pipe_label = pipe->pipe_peer->pipe_label =
80 	    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 pipe *pipe)
94 {
95 
96 	mac_pipe_label_free(pipe->pipe_label);
97 	pipe->pipe_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 pipe *pipe)
130 {
131 
132 	MAC_PERFORM(create_pipe, cred, pipe, pipe->pipe_label);
133 }
134 
135 static void
136 mac_relabel_pipe(struct ucred *cred, struct pipe *pipe, struct label *newlabel)
137 {
138 
139 	MAC_PERFORM(relabel_pipe, cred, pipe, pipe->pipe_label, newlabel);
140 }
141 
142 int
143 mac_check_pipe_ioctl(struct ucred *cred, struct pipe *pipe, unsigned long cmd,
144     void *data)
145 {
146 	int error;
147 
148 	PIPE_LOCK_ASSERT(pipe, MA_OWNED);
149 
150 	if (!mac_enforce_pipe)
151 		return (0);
152 
153 	MAC_CHECK(check_pipe_ioctl, cred, pipe, pipe->pipe_label, cmd, data);
154 
155 	return (error);
156 }
157 
158 int
159 mac_check_pipe_poll(struct ucred *cred, struct pipe *pipe)
160 {
161 	int error;
162 
163 	PIPE_LOCK_ASSERT(pipe, MA_OWNED);
164 
165 	if (!mac_enforce_pipe)
166 		return (0);
167 
168 	MAC_CHECK(check_pipe_poll, cred, pipe, pipe->pipe_label);
169 
170 	return (error);
171 }
172 
173 int
174 mac_check_pipe_read(struct ucred *cred, struct pipe *pipe)
175 {
176 	int error;
177 
178 	PIPE_LOCK_ASSERT(pipe, MA_OWNED);
179 
180 	if (!mac_enforce_pipe)
181 		return (0);
182 
183 	MAC_CHECK(check_pipe_read, cred, pipe, pipe->pipe_label);
184 
185 	return (error);
186 }
187 
188 static int
189 mac_check_pipe_relabel(struct ucred *cred, struct pipe *pipe,
190     struct label *newlabel)
191 {
192 	int error;
193 
194 	PIPE_LOCK_ASSERT(pipe, MA_OWNED);
195 
196 	if (!mac_enforce_pipe)
197 		return (0);
198 
199 	MAC_CHECK(check_pipe_relabel, cred, pipe, pipe->pipe_label, newlabel);
200 
201 	return (error);
202 }
203 
204 int
205 mac_check_pipe_stat(struct ucred *cred, struct pipe *pipe)
206 {
207 	int error;
208 
209 	PIPE_LOCK_ASSERT(pipe, MA_OWNED);
210 
211 	if (!mac_enforce_pipe)
212 		return (0);
213 
214 	MAC_CHECK(check_pipe_stat, cred, pipe, pipe->pipe_label);
215 
216 	return (error);
217 }
218 
219 int
220 mac_check_pipe_write(struct ucred *cred, struct pipe *pipe)
221 {
222 	int error;
223 
224 	PIPE_LOCK_ASSERT(pipe, MA_OWNED);
225 
226 	if (!mac_enforce_pipe)
227 		return (0);
228 
229 	MAC_CHECK(check_pipe_write, cred, pipe, pipe->pipe_label);
230 
231 	return (error);
232 }
233 
234 int
235 mac_pipe_label_set(struct ucred *cred, struct pipe *pipe, struct label *label)
236 {
237 	int error;
238 
239 	PIPE_LOCK_ASSERT(pipe, MA_OWNED);
240 
241 	error = mac_check_pipe_relabel(cred, pipe, label);
242 	if (error)
243 		return (error);
244 
245 	mac_relabel_pipe(cred, pipe, label);
246 
247 	return (0);
248 }
249