2 * SELinux NetLabel Support
4 * This file provides the necessary glue to tie NetLabel into the SELinux
7 * Author: Paul Moore <paul.moore@hp.com>
12 * (c) Copyright Hewlett-Packard Development Company, L.P., 2007
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
22 * the GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with this program; if not, write to the Free Software
26 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
30 #include <linux/spinlock.h>
31 #include <linux/rcupdate.h>
33 #include <net/netlabel.h>
39 * selinux_netlbl_sock_setsid - Label a socket using the NetLabel mechanism
40 * @sk: the socket to label
41 * @sid: the SID to use
44 * Attempt to label a socket using the NetLabel mechanism using the given
45 * SID. Returns zero values on success, negative values on failure. The
46 * caller is responsibile for calling rcu_read_lock() before calling this
47 * this function and rcu_read_unlock() after this function returns.
50 static int selinux_netlbl_sock_setsid(struct sock
*sk
, u32 sid
)
53 struct sk_security_struct
*sksec
= sk
->sk_security
;
54 struct netlbl_lsm_secattr secattr
;
56 netlbl_secattr_init(&secattr
);
58 rc
= security_netlbl_sid_to_secattr(sid
, &secattr
);
60 goto sock_setsid_return
;
61 rc
= netlbl_sock_setattr(sk
, &secattr
);
63 spin_lock_bh(&sksec
->nlbl_lock
);
64 sksec
->nlbl_state
= NLBL_LABELED
;
65 spin_unlock_bh(&sksec
->nlbl_lock
);
69 netlbl_secattr_destroy(&secattr
);
74 * selinux_netlbl_cache_invalidate - Invalidate the NetLabel cache
77 * Invalidate the NetLabel security attribute mapping cache.
80 void selinux_netlbl_cache_invalidate(void)
82 netlbl_cache_invalidate();
86 * selinux_netlbl_sk_security_reset - Reset the NetLabel fields
87 * @ssec: the sk_security_struct
88 * @family: the socket family
91 * Called when the NetLabel state of a sk_security_struct needs to be reset.
92 * The caller is responsibile for all the NetLabel sk_security_struct locking.
95 void selinux_netlbl_sk_security_reset(struct sk_security_struct
*ssec
,
98 if (family
== PF_INET
)
99 ssec
->nlbl_state
= NLBL_REQUIRE
;
101 ssec
->nlbl_state
= NLBL_UNSET
;
105 * selinux_netlbl_sk_security_init - Setup the NetLabel fields
106 * @ssec: the sk_security_struct
107 * @family: the socket family
110 * Called when a new sk_security_struct is allocated to initialize the NetLabel
114 void selinux_netlbl_sk_security_init(struct sk_security_struct
*ssec
,
117 /* No locking needed, we are the only one who has access to ssec */
118 selinux_netlbl_sk_security_reset(ssec
, family
);
119 spin_lock_init(&ssec
->nlbl_lock
);
123 * selinux_netlbl_sk_security_clone - Copy the NetLabel fields
124 * @ssec: the original sk_security_struct
125 * @newssec: the cloned sk_security_struct
128 * Clone the NetLabel specific sk_security_struct fields from @ssec to
132 void selinux_netlbl_sk_security_clone(struct sk_security_struct
*ssec
,
133 struct sk_security_struct
*newssec
)
135 /* We don't need to take newssec->nlbl_lock because we are the only
136 * thread with access to newssec, but we do need to take the RCU read
137 * lock as other threads could have access to ssec */
139 selinux_netlbl_sk_security_reset(newssec
, ssec
->sk
->sk_family
);
140 newssec
->sclass
= ssec
->sclass
;
145 * selinux_netlbl_skbuff_getsid - Get the sid of a packet using NetLabel
147 * @base_sid: the SELinux SID to use as a context for MLS only attributes
151 * Call the NetLabel mechanism to get the security attributes of the given
152 * packet and use those attributes to determine the correct context/SID to
153 * assign to the packet. Returns zero on success, negative values on failure.
156 int selinux_netlbl_skbuff_getsid(struct sk_buff
*skb
, u32 base_sid
, u32
*sid
)
159 struct netlbl_lsm_secattr secattr
;
161 if (!netlbl_enabled()) {
166 netlbl_secattr_init(&secattr
);
167 rc
= netlbl_skbuff_getattr(skb
, &secattr
);
168 if (rc
== 0 && secattr
.flags
!= NETLBL_SECATTR_NONE
) {
169 rc
= security_netlbl_secattr_to_sid(&secattr
, base_sid
, sid
);
171 (secattr
.flags
& NETLBL_SECATTR_CACHEABLE
) &&
172 (secattr
.flags
& NETLBL_SECATTR_CACHE
))
173 netlbl_cache_add(skb
, &secattr
);
176 netlbl_secattr_destroy(&secattr
);
182 * selinux_netlbl_sock_graft - Netlabel the new socket
183 * @sk: the new connection
184 * @sock: the new socket
187 * The connection represented by @sk is being grafted onto @sock so set the
188 * socket's NetLabel to match the SID of @sk.
191 void selinux_netlbl_sock_graft(struct sock
*sk
, struct socket
*sock
)
193 struct inode_security_struct
*isec
= SOCK_INODE(sock
)->i_security
;
194 struct sk_security_struct
*sksec
= sk
->sk_security
;
195 struct netlbl_lsm_secattr secattr
;
198 sksec
->sclass
= isec
->sclass
;
202 if (sksec
->nlbl_state
!= NLBL_REQUIRE
) {
207 netlbl_secattr_init(&secattr
);
208 if (netlbl_sock_getattr(sk
, &secattr
) == 0 &&
209 secattr
.flags
!= NETLBL_SECATTR_NONE
&&
210 security_netlbl_secattr_to_sid(&secattr
,
212 &nlbl_peer_sid
) == 0)
213 sksec
->peer_sid
= nlbl_peer_sid
;
214 netlbl_secattr_destroy(&secattr
);
216 /* Try to set the NetLabel on the socket to save time later, if we fail
217 * here we will pick up the pieces in later calls to
218 * selinux_netlbl_inode_permission(). */
219 selinux_netlbl_sock_setsid(sk
, sksec
->sid
);
225 * selinux_netlbl_socket_post_create - Label a socket using NetLabel
226 * @sock: the socket to label
229 * Attempt to label a socket using the NetLabel mechanism using the given
230 * SID. Returns zero values on success, negative values on failure.
233 int selinux_netlbl_socket_post_create(struct socket
*sock
)
236 struct sock
*sk
= sock
->sk
;
237 struct inode_security_struct
*isec
= SOCK_INODE(sock
)->i_security
;
238 struct sk_security_struct
*sksec
= sk
->sk_security
;
240 sksec
->sclass
= isec
->sclass
;
243 if (sksec
->nlbl_state
== NLBL_REQUIRE
)
244 rc
= selinux_netlbl_sock_setsid(sk
, sksec
->sid
);
251 * selinux_netlbl_inode_permission - Verify the socket is NetLabel labeled
252 * @inode: the file descriptor's inode
253 * @mask: the permission mask
256 * Looks at a file's inode and if it is marked as a socket protected by
257 * NetLabel then verify that the socket has been labeled, if not try to label
258 * the socket now with the inode's SID. Returns zero on success, negative
262 int selinux_netlbl_inode_permission(struct inode
*inode
, int mask
)
267 struct sk_security_struct
*sksec
;
269 if (!S_ISSOCK(inode
->i_mode
) ||
270 ((mask
& (MAY_WRITE
| MAY_APPEND
)) == 0))
272 sock
= SOCKET_I(inode
);
274 sksec
= sk
->sk_security
;
277 if (sksec
->nlbl_state
!= NLBL_REQUIRE
) {
282 bh_lock_sock_nested(sk
);
283 rc
= selinux_netlbl_sock_setsid(sk
, sksec
->sid
);
292 * selinux_netlbl_sock_rcv_skb - Do an inbound access check using NetLabel
293 * @sksec: the sock's sk_security_struct
295 * @ad: the audit data
298 * Fetch the NetLabel security attributes from @skb and perform an access check
299 * against the receiving socket. Returns zero on success, negative values on
303 int selinux_netlbl_sock_rcv_skb(struct sk_security_struct
*sksec
,
305 struct avc_audit_data
*ad
)
310 struct netlbl_lsm_secattr secattr
;
312 if (!netlbl_enabled())
315 netlbl_secattr_init(&secattr
);
316 rc
= netlbl_skbuff_getattr(skb
, &secattr
);
317 if (rc
== 0 && secattr
.flags
!= NETLBL_SECATTR_NONE
) {
318 rc
= security_netlbl_secattr_to_sid(&secattr
,
322 (secattr
.flags
& NETLBL_SECATTR_CACHEABLE
) &&
323 (secattr
.flags
& NETLBL_SECATTR_CACHE
))
324 netlbl_cache_add(skb
, &secattr
);
326 nlbl_sid
= SECINITSID_UNLABELED
;
327 netlbl_secattr_destroy(&secattr
);
331 switch (sksec
->sclass
) {
332 case SECCLASS_UDP_SOCKET
:
333 perm
= UDP_SOCKET__RECVFROM
;
335 case SECCLASS_TCP_SOCKET
:
336 perm
= TCP_SOCKET__RECVFROM
;
339 perm
= RAWIP_SOCKET__RECVFROM
;
342 rc
= avc_has_perm(sksec
->sid
, nlbl_sid
, sksec
->sclass
, perm
, ad
);
346 if (nlbl_sid
!= SECINITSID_UNLABELED
)
347 netlbl_skbuff_err(skb
, rc
);
352 * selinux_netlbl_socket_setsockopt - Do not allow users to remove a NetLabel
354 * @level: the socket level or protocol
355 * @optname: the socket option name
358 * Check the setsockopt() call and if the user is trying to replace the IP
359 * options on a socket and a NetLabel is in place for the socket deny the
360 * access; otherwise allow the access. Returns zero when the access is
361 * allowed, -EACCES when denied, and other negative values on error.
364 int selinux_netlbl_socket_setsockopt(struct socket
*sock
,
369 struct sock
*sk
= sock
->sk
;
370 struct sk_security_struct
*sksec
= sk
->sk_security
;
371 struct netlbl_lsm_secattr secattr
;
374 if (level
== IPPROTO_IP
&& optname
== IP_OPTIONS
&&
375 sksec
->nlbl_state
== NLBL_LABELED
) {
376 netlbl_secattr_init(&secattr
);
378 rc
= netlbl_sock_getattr(sk
, &secattr
);
380 if (rc
== 0 && secattr
.flags
!= NETLBL_SECATTR_NONE
)
382 netlbl_secattr_destroy(&secattr
);