mac_internal.h revision 165421 
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: head/sys/security/mac/mac_internal.h 165421 2006-12-20 23:12:36Z rwatson $
41 */
42
43/*
44 * MAC Framework sysctl namespace.
45 */
46#ifdef SYSCTL_DECL
47SYSCTL_DECL(_security_mac);
48#endif /* SYSCTL_DECL */
49
50/*
51 * MAC Framework global types and typedefs.
52 */
53LIST_HEAD(mac_policy_list_head, mac_policy_conf);
54#ifdef MALLOC_DECLARE
55MALLOC_DECLARE(M_MACTEMP);
56#endif
57
58/*
59 * MAC Framework global variables.
60 */
61extern struct mac_policy_list_head	mac_policy_list;
62extern struct mac_policy_list_head	mac_static_policy_list;
63extern int				mac_late;
64extern int				mac_enforce_network;
65extern int				mac_enforce_process;
66extern int				mac_enforce_socket;
67extern int				mac_enforce_vm;
68#ifndef MAC_ALWAYS_LABEL_MBUF
69extern int				mac_labelmbufs;
70#endif
71
72/*
73 * MAC Framework infrastructure functions.
74 */
75int	mac_error_select(int error1, int error2);
76
77void	mac_policy_grab_exclusive(void);
78void	mac_policy_assert_exclusive(void);
79void	mac_policy_release_exclusive(void);
80void	mac_policy_list_busy(void);
81int	mac_policy_list_conditional_busy(void);
82void	mac_policy_list_unbusy(void);
83
84struct label	*mac_labelzone_alloc(int flags);
85void		 mac_labelzone_free(struct label *label);
86void		 mac_labelzone_init(void);
87
88void	mac_init_label(struct label *label);
89void	mac_destroy_label(struct label *label);
90int	mac_check_structmac_consistent(struct mac *mac);
91int	mac_allocate_slot(void);
92
93/*
94 * MAC Framework per-object type functions.  It's not yet clear how the
95 * namespaces, etc, should work for these, so for now, sort by object type.
96 */
97struct label	*mac_pipe_label_alloc(void);
98void		 mac_pipe_label_free(struct label *label);
99struct label	*mac_socket_label_alloc(int flag);
100void		 mac_socket_label_free(struct label *label);
101
102int	mac_check_cred_relabel(struct ucred *cred, struct label *newlabel);
103int	mac_externalize_cred_label(struct label *label, char *elements,
104	    char *outbuf, size_t outbuflen);
105int	mac_internalize_cred_label(struct label *label, char *string);
106void	mac_relabel_cred(struct ucred *cred, struct label *newlabel);
107
108struct label	*mac_mbuf_to_label(struct mbuf *m);
109
110void	mac_copy_pipe_label(struct label *src, struct label *dest);
111int	mac_externalize_pipe_label(struct label *label, char *elements,
112	    char *outbuf, size_t outbuflen);
113int	mac_internalize_pipe_label(struct label *label, char *string);
114
115int	mac_socket_label_set(struct ucred *cred, struct socket *so,
116	    struct label *label);
117void	mac_copy_socket_label(struct label *src, struct label *dest);
118int	mac_externalize_socket_label(struct label *label, char *elements,
119	    char *outbuf, size_t outbuflen);
120int	mac_internalize_socket_label(struct label *label, char *string);
121
122int	mac_externalize_vnode_label(struct label *label, char *elements,
123	    char *outbuf, size_t outbuflen);
124int	mac_internalize_vnode_label(struct label *label, char *string);
125void	mac_check_vnode_mmap_downgrade(struct ucred *cred, struct vnode *vp,
126	    int *prot);
127int	vn_setlabel(struct vnode *vp, struct label *intlabel,
128	    struct ucred *cred);
129
130/*
131 * MAC_CHECK performs the designated check by walking the policy module list
132 * and checking with each as to how it feels about the request.  Note that it
133 * returns its value via 'error' in the scope of the caller.
134 */
135#define	MAC_CHECK(check, args...) do {					\
136	struct mac_policy_conf *mpc;					\
137	int entrycount;							\
138									\
139	error = 0;							\
140	LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) {		\
141		if (mpc->mpc_ops->mpo_ ## check != NULL)		\
142			error = mac_error_select(			\
143			    mpc->mpc_ops->mpo_ ## check (args),		\
144			    error);					\
145	}								\
146	if ((entrycount = mac_policy_list_conditional_busy()) != 0) {	\
147		LIST_FOREACH(mpc, &mac_policy_list, mpc_list) {		\
148			if (mpc->mpc_ops->mpo_ ## check != NULL)	\
149				error = mac_error_select(		\
150				    mpc->mpc_ops->mpo_ ## check (args),	\
151				    error);				\
152		}							\
153		mac_policy_list_unbusy();				\
154	}								\
155} while (0)
156
157/*
158 * MAC_GRANT performs the designated check by walking the policy module list
159 * and checking with each as to how it feels about the request.  Unlike
160 * MAC_CHECK, it grants if any policies return '0', and otherwise returns
161 * EPERM.  Note that it returns its value via 'error' in the scope of the
162 * caller.
163 */
164#define	MAC_GRANT(check, args...) do {					\
165	struct mac_policy_conf *mpc;					\
166	int entrycount;							\
167									\
168	error = EPERM;							\
169	LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) {		\
170		if (mpc->mpc_ops->mpo_ ## check != NULL) {		\
171			if (mpc->mpc_ops->mpo_ ## check(args) == 0)	\
172				error = 0;				\
173		}							\
174	}								\
175	if ((entrycount = mac_policy_list_conditional_busy()) != 0) {	\
176		LIST_FOREACH(mpc, &mac_policy_list, mpc_list) {		\
177			if (mpc->mpc_ops->mpo_ ## check != NULL) {	\
178				if (mpc->mpc_ops->mpo_ ## check (args)	\
179				    == 0)				\
180					error = 0;			\
181			}						\
182		}							\
183		mac_policy_list_unbusy();				\
184	}								\
185} while (0)
186
187/*
188 * MAC_BOOLEAN performs the designated boolean composition by walking the
189 * module list, invoking each instance of the operation, and combining the
190 * results using the passed C operator.  Note that it returns its value via
191 * 'result' in the scope of the caller, which should be initialized by the
192 * caller in a meaningful way to get a meaningful result.
193 */
194#define	MAC_BOOLEAN(operation, composition, args...) do {		\
195	struct mac_policy_conf *mpc;					\
196	int entrycount;							\
197									\
198	LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) {		\
199		if (mpc->mpc_ops->mpo_ ## operation != NULL)		\
200			result = result composition			\
201			    mpc->mpc_ops->mpo_ ## operation (args);	\
202	}								\
203	if ((entrycount = mac_policy_list_conditional_busy()) != 0) {	\
204		LIST_FOREACH(mpc, &mac_policy_list, mpc_list) {		\
205			if (mpc->mpc_ops->mpo_ ## operation != NULL)	\
206				result = result composition		\
207				    mpc->mpc_ops->mpo_ ## operation	\
208				    (args);				\
209		}							\
210		mac_policy_list_unbusy();				\
211	}								\
212} while (0)
213
214/*
215 * MAC_EXTERNALIZE queries each policy to see if it can generate an
216 * externalized version of a label element by name.  Policies declare whether
217 * they have matched a particular element name, parsed from the string by
218 * MAC_EXTERNALIZE, and an error is returned if any element is matched by no
219 * policy.
220 */
221#define	MAC_EXTERNALIZE(type, label, elementlist, outbuf, 		\
222    outbuflen) do {							\
223	int claimed, first, ignorenotfound, savedlen;			\
224	char *element_name, *element_temp;				\
225	struct sbuf sb;							\
226									\
227	error = 0;							\
228	first = 1;							\
229	sbuf_new(&sb, outbuf, outbuflen, SBUF_FIXEDLEN);		\
230	element_temp = elementlist;					\
231	while ((element_name = strsep(&element_temp, ",")) != NULL) {	\
232		if (element_name[0] == '?') {				\
233			element_name++;					\
234			ignorenotfound = 1;				\
235		 } else							\
236			ignorenotfound = 0;				\
237		savedlen = sbuf_len(&sb);				\
238		if (first)						\
239			error = sbuf_printf(&sb, "%s/", element_name);	\
240		else							\
241			error = sbuf_printf(&sb, ",%s/", element_name);	\
242		if (error == -1) {					\
243			error = EINVAL;	/* XXX: E2BIG? */		\
244			break;						\
245		}							\
246		claimed = 0;						\
247		MAC_CHECK(externalize_ ## type ## _label, label,	\
248		    element_name, &sb, &claimed);			\
249		if (error)						\
250			break;						\
251		if (claimed == 0 && ignorenotfound) {			\
252			/* Revert last label name. */			\
253			sbuf_setpos(&sb, savedlen);			\
254		} else if (claimed != 1) {				\
255			error = EINVAL;	/* XXX: ENOLABEL? */		\
256			break;						\
257		} else {						\
258			first = 0;					\
259		}							\
260	}								\
261	sbuf_finish(&sb);						\
262} while (0)
263
264/*
265 * MAC_INTERNALIZE presents parsed element names and data to each policy to
266 * see if any is willing to claim it and internalize the label data.  If no
267 * policies match, an error is returned.
268 */
269#define	MAC_INTERNALIZE(type, label, instring) do {			\
270	char *element, *element_name, *element_data;			\
271	int claimed;							\
272									\
273	error = 0;							\
274	element = instring;						\
275	while ((element_name = strsep(&element, ",")) != NULL) {	\
276		element_data = element_name;				\
277		element_name = strsep(&element_data, "/");		\
278		if (element_data == NULL) {				\
279			error = EINVAL;					\
280			break;						\
281		}							\
282		claimed = 0;						\
283		MAC_CHECK(internalize_ ## type ## _label, label,	\
284		    element_name, element_data, &claimed);		\
285		if (error)						\
286			break;						\
287		if (claimed != 1) {					\
288			/* XXXMAC: Another error here? */		\
289			error = EINVAL;					\
290			break;						\
291		}							\
292	}								\
293} while (0)
294
295/*
296 * MAC_PERFORM performs the designated operation by walking the policy module
297 * list and invoking that operation for each policy.
298 */
299#define	MAC_PERFORM(operation, args...) do {				\
300	struct mac_policy_conf *mpc;					\
301	int entrycount;							\
302									\
303	LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) {		\
304		if (mpc->mpc_ops->mpo_ ## operation != NULL)		\
305			mpc->mpc_ops->mpo_ ## operation (args);		\
306	}								\
307	if ((entrycount = mac_policy_list_conditional_busy()) != 0) {	\
308		LIST_FOREACH(mpc, &mac_policy_list, mpc_list) {		\
309			if (mpc->mpc_ops->mpo_ ## operation != NULL)	\
310				mpc->mpc_ops->mpo_ ## operation (args);	\
311		}							\
312		mac_policy_list_unbusy();				\
313	}								\
314} while (0)
315