1/*-
2 * Copyright (c) 1999-2002 Robert N. M. Watson
3 * Copyright (c) 2001-2002 Networks Associates Technology, Inc.
4 * All rights reserved.
5 *
6 * This software was developed by Robert Watson for the TrustedBSD Project.
7 *
8 * This software was developed for the FreeBSD Project in part by Network
9 * Associates Laboratories, the Security Research Division of Network
10 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
11 * as part of the DARPA CHATS research program.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * $FreeBSD: head/sys/security/mac_partition/mac_partition.c 126097 2004-02-22 00:33:12Z rwatson $
35 */
36
37/*
38 * Developed by the TrustedBSD Project.
39 * Experiment with a partition-like model.
40 */
41
42#include <sys/types.h>
43#include <sys/param.h>
44#include <sys/conf.h>
45#include <sys/kernel.h>
46#include <sys/mac.h>
47#include <sys/mount.h>
48#include <sys/proc.h>
49#include <sys/sbuf.h>
50#include <sys/systm.h>
51#include <sys/sysproto.h>
52#include <sys/sysent.h>
53#include <sys/vnode.h>
54#include <sys/file.h>
55#include <sys/socket.h>
56#include <sys/socketvar.h>
57#include <sys/sysctl.h>
58
59#include <fs/devfs/devfs.h>
60
61#include <net/bpfdesc.h>
62#include <net/if.h>
63#include <net/if_types.h>
64#include <net/if_var.h>
65
66#include <vm/vm.h>
67
68#include <sys/mac_policy.h>
69
70#include <security/mac_partition/mac_partition.h>
71
72SYSCTL_DECL(_security_mac);
73
74SYSCTL_NODE(_security_mac, OID_AUTO, partition, CTLFLAG_RW, 0,
75 "TrustedBSD mac_partition policy controls");
76
77static int mac_partition_enabled = 1;
78SYSCTL_INT(_security_mac_partition, OID_AUTO, enabled, CTLFLAG_RW,
79 &mac_partition_enabled, 0, "Enforce partition policy");
80
81static int partition_slot;
82#define SLOT(l) (LABEL_TO_SLOT((l), partition_slot).l_long)
83
84static void
85mac_partition_init(struct mac_policy_conf *conf)
86{
87
88}
89
90static void
91mac_partition_init_label(struct label *label)
92{
93
94 SLOT(label) = 0;
95}
96
97static void
98mac_partition_destroy_label(struct label *label)
99{
100
101 SLOT(label) = 0;
102}
103
104static void
105mac_partition_copy_label(struct label *src, struct label *dest)
106{
107
108 SLOT(dest) = SLOT(src);
109}
110
111static int
112mac_partition_externalize_label(struct label *label, char *element_name,
113 struct sbuf *sb, int *claimed)
114{
115
116 if (strcmp(MAC_PARTITION_LABEL_NAME, element_name) != 0)
117 return (0);
118
119 (*claimed)++;
120
121 if (sbuf_printf(sb, "%ld", SLOT(label)) == -1)
122 return (EINVAL);
123 else
124 return (0);
125}
126
127static int
128mac_partition_internalize_label(struct label *label, char *element_name,
129 char *element_data, int *claimed)
130{
131
132 if (strcmp(MAC_PARTITION_LABEL_NAME, element_name) != 0)
133 return (0);
134
135 (*claimed)++;
136 SLOT(label) = strtol(element_data, NULL, 10);
137 return (0);
138}
139
140static void
141mac_partition_create_proc0(struct ucred *cred)
142{
143
144 SLOT(cred->cr_label) = 0;
145}
146
147static void
148mac_partition_create_proc1(struct ucred *cred)
149{
150
151 SLOT(cred->cr_label) = 0;
152}
153
154static void
155mac_partition_relabel_cred(struct ucred *cred, struct label *newlabel)
156{
157
158 if (SLOT(newlabel) != 0)
159 SLOT(cred->cr_label) = SLOT(newlabel);
160}
161
162static int
163label_on_label(struct label *subject, struct label *object)
164{
165
166 if (mac_partition_enabled == 0)
167 return (0);
168
169 if (SLOT(subject) == 0)
170 return (0);
171
172 if (SLOT(subject) == SLOT(object))
173 return (0);
174
175 return (EPERM);
176}
177
178static int
179mac_partition_check_cred_relabel(struct ucred *cred, struct label *newlabel)
180{
181 int error;
182
183 error = 0;
184
185 /* Treat "0" as a no-op request. */
186 if (SLOT(newlabel) != 0) {
187 /*
188 * Require BSD privilege in order to change the partition.
189 * Originally we also required that the process not be
190 * in a partition in the first place, but this didn't
191 * interact well with sendmail.
192 */
193 error = suser_cred(cred, 0);
194 }
195
196 return (error);
197}
198
199static int
200mac_partition_check_cred_visible(struct ucred *u1, struct ucred *u2)
201{
202 int error;
203
204 error = label_on_label(u1->cr_label, u2->cr_label);
205
206 return (error == 0 ? 0 : ESRCH);
207}
208
209static int
210mac_partition_check_proc_debug(struct ucred *cred, struct proc *proc)
211{
212 int error;
213
214 error = label_on_label(cred->cr_label, proc->p_ucred->cr_label);
215
216 return (error ? ESRCH : 0);
217}
218
219static int
220mac_partition_check_proc_sched(struct ucred *cred, struct proc *proc)
221{
222 int error;
223
224 error = label_on_label(cred->cr_label, proc->p_ucred->cr_label);
225
226 return (error ? ESRCH : 0);
227}
228
229static int
230mac_partition_check_proc_signal(struct ucred *cred, struct proc *proc,
231 int signum)
232{
233 int error;
234
235 error = label_on_label(cred->cr_label, proc->p_ucred->cr_label);
236
237 return (error ? ESRCH : 0);
238}
239
240static int
241mac_partition_check_socket_visible(struct ucred *cred, struct socket *socket,
242 struct label *socketlabel)
243{
244 int error;
245
246 error = label_on_label(cred->cr_label, socketlabel);
247
248 return (error ? ENOENT : 0);
249}
250
251static int
252mac_partition_check_vnode_exec(struct ucred *cred, struct vnode *vp,
253 struct label *label, struct image_params *imgp, struct label *execlabel)
254{
255
256 if (execlabel != NULL) {
257 /*
258 * We currently don't permit labels to be changed at
259 * exec-time as part of the partition model, so disallow
260 * non-NULL partition label changes in execlabel.
261 */
262 if (SLOT(execlabel) != 0)
263 return (EINVAL);
264 }
265
266 return (0);
267}
268
269static struct mac_policy_ops mac_partition_ops =
270{
271 .mpo_init = mac_partition_init,
272 .mpo_init_cred_label = mac_partition_init_label,
273 .mpo_destroy_cred_label = mac_partition_destroy_label,
274 .mpo_copy_cred_label = mac_partition_copy_label,
275 .mpo_externalize_cred_label = mac_partition_externalize_label,
276 .mpo_internalize_cred_label = mac_partition_internalize_label,
277 .mpo_create_proc0 = mac_partition_create_proc0,
278 .mpo_create_proc1 = mac_partition_create_proc1,
279 .mpo_relabel_cred = mac_partition_relabel_cred,
280 .mpo_check_cred_relabel = mac_partition_check_cred_relabel,
281 .mpo_check_cred_visible = mac_partition_check_cred_visible,
282 .mpo_check_proc_debug = mac_partition_check_proc_debug,
283 .mpo_check_proc_sched = mac_partition_check_proc_sched,
284 .mpo_check_proc_signal = mac_partition_check_proc_signal,
285 .mpo_check_socket_visible = mac_partition_check_socket_visible,
286 .mpo_check_vnode_exec = mac_partition_check_vnode_exec,
287};
288
289MAC_POLICY_SET(&mac_partition_ops, mac_partition, "TrustedBSD MAC/Partition",
290 MPC_LOADTIME_FLAG_UNLOADOK, &partition_slot);