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 rc = security_netlbl_sid_to_secattr(sid, &secattr);
60 rc = netlbl_sock_setattr(sk, &secattr);
62 spin_lock_bh(&sksec->nlbl_lock);
63 sksec->nlbl_state = NLBL_LABELED;
64 spin_unlock_bh(&sksec->nlbl_lock);
71 * selinux_netlbl_cache_invalidate - Invalidate the NetLabel cache
74 * Invalidate the NetLabel security attribute mapping cache.
77 void selinux_netlbl_cache_invalidate(void)
79 netlbl_cache_invalidate();
83 * selinux_netlbl_sk_security_reset - Reset the NetLabel fields
84 * @ssec: the sk_security_struct
85 * @family: the socket family
88 * Called when the NetLabel state of a sk_security_struct needs to be reset.
89 * The caller is responsibile for all the NetLabel sk_security_struct locking.
92 void selinux_netlbl_sk_security_reset(struct sk_security_struct *ssec,
95 if (family == PF_INET)
96 ssec->nlbl_state = NLBL_REQUIRE;
98 ssec->nlbl_state = NLBL_UNSET;
102 * selinux_netlbl_sk_security_init - Setup the NetLabel fields
103 * @ssec: the sk_security_struct
104 * @family: the socket family
107 * Called when a new sk_security_struct is allocated to initialize the NetLabel
111 void selinux_netlbl_sk_security_init(struct sk_security_struct *ssec,
114 /* No locking needed, we are the only one who has access to ssec */
115 selinux_netlbl_sk_security_reset(ssec, family);
116 spin_lock_init(&ssec->nlbl_lock);
120 * selinux_netlbl_sk_security_clone - Copy the NetLabel fields
121 * @ssec: the original sk_security_struct
122 * @newssec: the cloned sk_security_struct
125 * Clone the NetLabel specific sk_security_struct fields from @ssec to
129 void selinux_netlbl_sk_security_clone(struct sk_security_struct *ssec,
130 struct sk_security_struct *newssec)
132 /* We don't need to take newssec->nlbl_lock because we are the only
133 * thread with access to newssec, but we do need to take the RCU read
134 * lock as other threads could have access to ssec */
136 selinux_netlbl_sk_security_reset(newssec, ssec->sk->sk_family);
137 newssec->sclass = ssec->sclass;
142 * selinux_netlbl_skbuff_getsid - Get the sid of a packet using NetLabel
144 * @base_sid: the SELinux SID to use as a context for MLS only attributes
148 * Call the NetLabel mechanism to get the security attributes of the given
149 * packet and use those attributes to determine the correct context/SID to
150 * assign to the packet. Returns zero on success, negative values on failure.
153 int selinux_netlbl_skbuff_getsid(struct sk_buff *skb, u32 base_sid, u32 *sid)
156 struct netlbl_lsm_secattr secattr;
158 if (!netlbl_enabled()) {
163 netlbl_secattr_init(&secattr);
164 rc = netlbl_skbuff_getattr(skb, &secattr);
165 if (rc == 0 && secattr.flags != NETLBL_SECATTR_NONE)
166 rc = security_netlbl_secattr_to_sid(&secattr,
171 netlbl_secattr_destroy(&secattr);
177 * selinux_netlbl_sock_graft - Netlabel the new socket
178 * @sk: the new connection
179 * @sock: the new socket
182 * The connection represented by @sk is being grafted onto @sock so set the
183 * socket's NetLabel to match the SID of @sk.
186 void selinux_netlbl_sock_graft(struct sock *sk, struct socket *sock)
188 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
189 struct sk_security_struct *sksec = sk->sk_security;
190 struct netlbl_lsm_secattr secattr;
193 sksec->sclass = isec->sclass;
197 if (sksec->nlbl_state != NLBL_REQUIRE) {
202 netlbl_secattr_init(&secattr);
203 if (netlbl_sock_getattr(sk, &secattr) == 0 &&
204 secattr.flags != NETLBL_SECATTR_NONE &&
205 security_netlbl_secattr_to_sid(&secattr,
206 SECINITSID_UNLABELED,
207 &nlbl_peer_sid) == 0)
208 sksec->peer_sid = nlbl_peer_sid;
209 netlbl_secattr_destroy(&secattr);
211 /* Try to set the NetLabel on the socket to save time later, if we fail
212 * here we will pick up the pieces in later calls to
213 * selinux_netlbl_inode_permission(). */
214 selinux_netlbl_sock_setsid(sk, sksec->sid);
220 * selinux_netlbl_socket_post_create - Label a socket using NetLabel
221 * @sock: the socket to label
224 * Attempt to label a socket using the NetLabel mechanism using the given
225 * SID. Returns zero values on success, negative values on failure.
228 int selinux_netlbl_socket_post_create(struct socket *sock)
231 struct sock *sk = sock->sk;
232 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
233 struct sk_security_struct *sksec = sk->sk_security;
235 sksec->sclass = isec->sclass;
238 if (sksec->nlbl_state == NLBL_REQUIRE)
239 rc = selinux_netlbl_sock_setsid(sk, sksec->sid);
246 * selinux_netlbl_inode_permission - Verify the socket is NetLabel labeled
247 * @inode: the file descriptor's inode
248 * @mask: the permission mask
251 * Looks at a file's inode and if it is marked as a socket protected by
252 * NetLabel then verify that the socket has been labeled, if not try to label
253 * the socket now with the inode's SID. Returns zero on success, negative
257 int selinux_netlbl_inode_permission(struct inode *inode, int mask)
262 struct sk_security_struct *sksec;
264 if (!S_ISSOCK(inode->i_mode) ||
265 ((mask & (MAY_WRITE | MAY_APPEND)) == 0))
267 sock = SOCKET_I(inode);
269 sksec = sk->sk_security;
272 if (sksec->nlbl_state != NLBL_REQUIRE) {
277 bh_lock_sock_nested(sk);
278 rc = selinux_netlbl_sock_setsid(sk, sksec->sid);
287 * selinux_netlbl_sock_rcv_skb - Do an inbound access check using NetLabel
288 * @sksec: the sock's sk_security_struct
290 * @ad: the audit data
293 * Fetch the NetLabel security attributes from @skb and perform an access check
294 * against the receiving socket. Returns zero on success, negative values on
298 int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec,
300 struct avc_audit_data *ad)
306 if (!netlbl_enabled())
309 rc = selinux_netlbl_skbuff_getsid(skb,
310 SECINITSID_UNLABELED,
315 if (netlbl_sid == SECSID_NULL)
318 switch (sksec->sclass) {
319 case SECCLASS_UDP_SOCKET:
320 recv_perm = UDP_SOCKET__RECVFROM;
322 case SECCLASS_TCP_SOCKET:
323 recv_perm = TCP_SOCKET__RECVFROM;
326 recv_perm = RAWIP_SOCKET__RECVFROM;
329 rc = avc_has_perm(sksec->sid,
337 netlbl_skbuff_err(skb, rc);
342 * selinux_netlbl_socket_setsockopt - Do not allow users to remove a NetLabel
344 * @level: the socket level or protocol
345 * @optname: the socket option name
348 * Check the setsockopt() call and if the user is trying to replace the IP
349 * options on a socket and a NetLabel is in place for the socket deny the
350 * access; otherwise allow the access. Returns zero when the access is
351 * allowed, -EACCES when denied, and other negative values on error.
354 int selinux_netlbl_socket_setsockopt(struct socket *sock,
359 struct sock *sk = sock->sk;
360 struct sk_security_struct *sksec = sk->sk_security;
361 struct netlbl_lsm_secattr secattr;
364 if (level == IPPROTO_IP && optname == IP_OPTIONS &&
365 sksec->nlbl_state == NLBL_LABELED) {
366 netlbl_secattr_init(&secattr);
368 rc = netlbl_sock_getattr(sk, &secattr);
370 if (rc == 0 && secattr.flags != NETLBL_SECATTR_NONE)
372 netlbl_secattr_destroy(&secattr);