xref: /freebsd/sys/security/mac/mac_internal.h (revision 57c4583f70ab9d25b3aed17f20ec7843f9673539)
1 /*-
2  * Copyright (c) 1999-2002 Robert N. M. Watson
3  * Copyright (c) 2001 Ilmar S. Habibulin
4  * Copyright (c) 2001-2004 Networks Associates Technology, Inc.
5  * Copyright (c) 2006 nCircle Network Security, Inc.
6  * All rights reserved.
7  *
8  * This software was developed by Robert Watson and Ilmar Habibulin for the
9  * TrustedBSD Project.
10  *
11  * This software was developed for the FreeBSD Project in part by Network
12  * Associates Laboratories, the Security Research Division of Network
13  * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
14  * as part of the DARPA CHATS research program.
15  *
16  * This software was developed by Robert N. M. Watson for the TrustedBSD
17  * Project under contract to nCircle Network Security, Inc.
18  *
19  * Redistribution and use in source and binary forms, with or without
20  * modification, are permitted provided that the following conditions
21  * are met:
22  * 1. Redistributions of source code must retain the above copyright
23  *    notice, this list of conditions and the following disclaimer.
24  * 2. Redistributions in binary form must reproduce the above copyright
25  *    notice, this list of conditions and the following disclaimer in the
26  *    documentation and/or other materials provided with the distribution.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  *
40  * $FreeBSD$
41  */
42 
43 /*
44  * MAC Framework sysctl namespace.
45  */
46 #ifdef SYSCTL_DECL
47 SYSCTL_DECL(_security_mac);
48 #endif /* SYSCTL_DECL */
49 
50 /*
51  * MAC Framework global types and typedefs.
52  */
53 LIST_HEAD(mac_policy_list_head, mac_policy_conf);
54 #ifdef MALLOC_DECLARE
55 MALLOC_DECLARE(M_MACTEMP);
56 #endif
57 
58 /*
59  * MAC Framework global variables.
60  */
61 extern struct mac_policy_list_head	mac_policy_list;
62 extern struct mac_policy_list_head	mac_static_policy_list;
63 extern int				mac_late;
64 extern int				mac_enforce_network;
65 extern int				mac_enforce_process;
66 extern int				mac_enforce_socket;
67 extern int				mac_enforce_vm;
68 #ifndef MAC_ALWAYS_LABEL_MBUF
69 extern int				mac_labelmbufs;
70 #endif
71 
72 /*
73  * MAC Framework infrastructure functions.
74  */
75 int	mac_error_select(int error1, int error2);
76 
77 void	mac_policy_grab_exclusive(void);
78 void	mac_policy_assert_exclusive(void);
79 void	mac_policy_release_exclusive(void);
80 void	mac_policy_list_busy(void);
81 int	mac_policy_list_conditional_busy(void);
82 void	mac_policy_list_unbusy(void);
83 
84 struct label	*mac_labelzone_alloc(int flags);
85 void		 mac_labelzone_free(struct label *label);
86 void		 mac_labelzone_init(void);
87 
88 void	mac_init_label(struct label *label);
89 void	mac_destroy_label(struct label *label);
90 int	mac_check_structmac_consistent(struct mac *mac);
91 int	mac_allocate_slot(void);
92 
93 /*
94  * MAC Framework per-object type functions.  It's not yet clear how
95  * the namespaces, etc, should work for these, so for now, sort by
96  * object type.
97  */
98 struct label	*mac_pipe_label_alloc(void);
99 void		 mac_pipe_label_free(struct label *label);
100 struct label	*mac_socket_label_alloc(int flag);
101 void		 mac_socket_label_free(struct label *label);
102 
103 int	mac_check_cred_relabel(struct ucred *cred, struct label *newlabel);
104 int	mac_externalize_cred_label(struct label *label, char *elements,
105 	    char *outbuf, size_t outbuflen);
106 int	mac_internalize_cred_label(struct label *label, char *string);
107 void	mac_relabel_cred(struct ucred *cred, struct label *newlabel);
108 
109 struct label	*mac_mbuf_to_label(struct mbuf *m);
110 
111 void	mac_copy_pipe_label(struct label *src, struct label *dest);
112 int	mac_externalize_pipe_label(struct label *label, char *elements,
113 	    char *outbuf, size_t outbuflen);
114 int	mac_internalize_pipe_label(struct label *label, char *string);
115 
116 int	mac_socket_label_set(struct ucred *cred, struct socket *so,
117 	    struct label *label);
118 void	mac_copy_socket_label(struct label *src, struct label *dest);
119 int	mac_externalize_socket_label(struct label *label, char *elements,
120 	    char *outbuf, size_t outbuflen);
121 int	mac_internalize_socket_label(struct label *label, char *string);
122 
123 int	mac_externalize_vnode_label(struct label *label, char *elements,
124 	    char *outbuf, size_t outbuflen);
125 int	mac_internalize_vnode_label(struct label *label, char *string);
126 void	mac_check_vnode_mmap_downgrade(struct ucred *cred, struct vnode *vp,
127 	    int *prot);
128 int	vn_setlabel(struct vnode *vp, struct label *intlabel,
129 	    struct ucred *cred);
130 
131 /*
132  * MAC_CHECK performs the designated check by walking the policy module
133  * list and checking with each as to how it feels about the request.
134  * Note that it returns its value via 'error' in the scope of the caller.
135  */
136 #define	MAC_CHECK(check, args...) do {					\
137 	struct mac_policy_conf *mpc;					\
138 	int entrycount;							\
139 									\
140 	error = 0;							\
141 	LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) {		\
142 		if (mpc->mpc_ops->mpo_ ## check != NULL)		\
143 			error = mac_error_select(			\
144 			    mpc->mpc_ops->mpo_ ## check (args),		\
145 			    error);					\
146 	}								\
147 	if ((entrycount = mac_policy_list_conditional_busy()) != 0) {	\
148 		LIST_FOREACH(mpc, &mac_policy_list, mpc_list) {		\
149 			if (mpc->mpc_ops->mpo_ ## check != NULL)	\
150 				error = mac_error_select(		\
151 				    mpc->mpc_ops->mpo_ ## check (args),	\
152 				    error);				\
153 		}							\
154 		mac_policy_list_unbusy();				\
155 	}								\
156 } while (0)
157 
158 /*
159  * MAC_GRANT performs the designated check by walking the policy module
160  * list and checking with each as to how it feels about the request.  Unlike
161  * MAC_CHECK, it grants if any policies return '0', and otherwise returns
162  * EPERM.  Note that it returns its value via 'error' in the scope of the
163  * caller.
164  */
165 #define	MAC_GRANT(check, args...) do {					\
166 	struct mac_policy_conf *mpc;					\
167 	int entrycount;							\
168 									\
169 	error = EPERM;							\
170 	LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) {		\
171 		if (mpc->mpc_ops->mpo_ ## check != NULL) {		\
172 			if (mpc->mpc_ops->mpo_ ## check(args) == 0)	\
173 				error = 0;				\
174 		}							\
175 	}								\
176 	if ((entrycount = mac_policy_list_conditional_busy()) != 0) {	\
177 		LIST_FOREACH(mpc, &mac_policy_list, mpc_list) {		\
178 			if (mpc->mpc_ops->mpo_ ## check != NULL) {	\
179 				if (mpc->mpc_ops->mpo_ ## check (args)	\
180 				    == 0)				\
181 					error = 0;			\
182 			}						\
183 		}							\
184 		mac_policy_list_unbusy();				\
185 	}								\
186 } while (0)
187 
188 /*
189  * MAC_BOOLEAN performs the designated boolean composition by walking
190  * the module list, invoking each instance of the operation, and
191  * combining the results using the passed C operator.  Note that it
192  * returns its value via 'result' in the scope of the caller, which
193  * should be initialized by the caller in a meaningful way to get
194  * a meaningful result.
195  */
196 #define	MAC_BOOLEAN(operation, composition, args...) do {		\
197 	struct mac_policy_conf *mpc;					\
198 	int entrycount;							\
199 									\
200 	LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) {		\
201 		if (mpc->mpc_ops->mpo_ ## operation != NULL)		\
202 			result = result composition			\
203 			    mpc->mpc_ops->mpo_ ## operation (args);	\
204 	}								\
205 	if ((entrycount = mac_policy_list_conditional_busy()) != 0) {	\
206 		LIST_FOREACH(mpc, &mac_policy_list, mpc_list) {		\
207 			if (mpc->mpc_ops->mpo_ ## operation != NULL)	\
208 				result = result composition		\
209 				    mpc->mpc_ops->mpo_ ## operation	\
210 				    (args);				\
211 		}							\
212 		mac_policy_list_unbusy();				\
213 	}								\
214 } while (0)
215 
216 #define	MAC_EXTERNALIZE(type, label, elementlist, outbuf, 		\
217     outbuflen) do {							\
218 	int claimed, first, ignorenotfound, savedlen;			\
219 	char *element_name, *element_temp;				\
220 	struct sbuf sb;							\
221 									\
222 	error = 0;							\
223 	first = 1;							\
224 	sbuf_new(&sb, outbuf, outbuflen, SBUF_FIXEDLEN);		\
225 	element_temp = elementlist;					\
226 	while ((element_name = strsep(&element_temp, ",")) != NULL) {	\
227 		if (element_name[0] == '?') {				\
228 			element_name++;					\
229 			ignorenotfound = 1;				\
230 		 } else							\
231 			ignorenotfound = 0;				\
232 		savedlen = sbuf_len(&sb);				\
233 		if (first)						\
234 			error = sbuf_printf(&sb, "%s/", element_name);	\
235 		else							\
236 			error = sbuf_printf(&sb, ",%s/", element_name);	\
237 		if (error == -1) {					\
238 			error = EINVAL;	/* XXX: E2BIG? */		\
239 			break;						\
240 		}							\
241 		claimed = 0;						\
242 		MAC_CHECK(externalize_ ## type ## _label, label,	\
243 		    element_name, &sb, &claimed);			\
244 		if (error)						\
245 			break;						\
246 		if (claimed == 0 && ignorenotfound) {			\
247 			/* Revert last label name. */			\
248 			sbuf_setpos(&sb, savedlen);			\
249 		} else if (claimed != 1) {				\
250 			error = EINVAL;	/* XXX: ENOLABEL? */		\
251 			break;						\
252 		} else {						\
253 			first = 0;					\
254 		}							\
255 	}								\
256 	sbuf_finish(&sb);						\
257 } while (0)
258 
259 #define	MAC_INTERNALIZE(type, label, instring) do {			\
260 	char *element, *element_name, *element_data;			\
261 	int claimed;							\
262 									\
263 	error = 0;							\
264 	element = instring;						\
265 	while ((element_name = strsep(&element, ",")) != NULL) {	\
266 		element_data = element_name;				\
267 		element_name = strsep(&element_data, "/");		\
268 		if (element_data == NULL) {				\
269 			error = EINVAL;					\
270 			break;						\
271 		}							\
272 		claimed = 0;						\
273 		MAC_CHECK(internalize_ ## type ## _label, label,	\
274 		    element_name, element_data, &claimed);		\
275 		if (error)						\
276 			break;						\
277 		if (claimed != 1) {					\
278 			/* XXXMAC: Another error here? */		\
279 			error = EINVAL;					\
280 			break;						\
281 		}							\
282 	}								\
283 } while (0)
284 
285 /*
286  * MAC_PERFORM performs the designated operation by walking the policy
287  * module list and invoking that operation for each policy.
288  */
289 #define	MAC_PERFORM(operation, args...) do {				\
290 	struct mac_policy_conf *mpc;					\
291 	int entrycount;							\
292 									\
293 	LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) {		\
294 		if (mpc->mpc_ops->mpo_ ## operation != NULL)		\
295 			mpc->mpc_ops->mpo_ ## operation (args);		\
296 	}								\
297 	if ((entrycount = mac_policy_list_conditional_busy()) != 0) {	\
298 		LIST_FOREACH(mpc, &mac_policy_list, mpc_list) {		\
299 			if (mpc->mpc_ops->mpo_ ## operation != NULL)	\
300 				mpc->mpc_ops->mpo_ ## operation (args);	\
301 		}							\
302 		mac_policy_list_unbusy();				\
303 	}								\
304 } while (0)
305