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_sidlookup_cached - Cache a SID lookup
41 * @secattr: the NetLabel security attributes
45 * Query the SELinux security server to lookup the correct SID for the given
46 * security attributes. If the query is successful, cache the result to speed
47 * up future lookups. Returns zero on success, negative values on failure.
50 static int selinux_netlbl_sidlookup_cached(struct sk_buff *skb,
51 struct netlbl_lsm_secattr *secattr,
56 rc = security_netlbl_secattr_to_sid(secattr, sid);
58 (secattr->flags & NETLBL_SECATTR_CACHEABLE) &&
59 (secattr->flags & NETLBL_SECATTR_CACHE))
60 netlbl_cache_add(skb, secattr);
66 * selinux_netlbl_sock_setsid - Label a socket using the NetLabel mechanism
67 * @sk: the socket to label
68 * @sid: the SID to use
71 * Attempt to label a socket using the NetLabel mechanism using the given
72 * SID. Returns zero values on success, negative values on failure.
75 static int selinux_netlbl_sock_setsid(struct sock *sk, u32 sid)
78 struct sk_security_struct *sksec = sk->sk_security;
79 struct netlbl_lsm_secattr secattr;
81 netlbl_secattr_init(&secattr);
83 rc = security_netlbl_sid_to_secattr(sid, &secattr);
85 goto sock_setsid_return;
86 rc = netlbl_sock_setattr(sk, &secattr);
88 sksec->nlbl_state = NLBL_LABELED;
91 netlbl_secattr_destroy(&secattr);
96 * selinux_netlbl_cache_invalidate - Invalidate the NetLabel cache
99 * Invalidate the NetLabel security attribute mapping cache.
102 void selinux_netlbl_cache_invalidate(void)
104 netlbl_cache_invalidate();
108 * selinux_netlbl_sk_security_reset - Reset the NetLabel fields
109 * @ssec: the sk_security_struct
110 * @family: the socket family
113 * Called when the NetLabel state of a sk_security_struct needs to be reset.
114 * The caller is responsibile for all the NetLabel sk_security_struct locking.
117 void selinux_netlbl_sk_security_reset(struct sk_security_struct *ssec,
120 if (family == PF_INET)
121 ssec->nlbl_state = NLBL_REQUIRE;
123 ssec->nlbl_state = NLBL_UNSET;
127 * selinux_netlbl_skbuff_getsid - Get the sid of a packet using NetLabel
129 * @family: protocol family
130 * @type: NetLabel labeling protocol type
134 * Call the NetLabel mechanism to get the security attributes of the given
135 * packet and use those attributes to determine the correct context/SID to
136 * assign to the packet. Returns zero on success, negative values on failure.
139 int selinux_netlbl_skbuff_getsid(struct sk_buff *skb,
145 struct netlbl_lsm_secattr secattr;
147 if (!netlbl_enabled()) {
152 netlbl_secattr_init(&secattr);
153 rc = netlbl_skbuff_getattr(skb, family, &secattr);
154 if (rc == 0 && secattr.flags != NETLBL_SECATTR_NONE)
155 rc = selinux_netlbl_sidlookup_cached(skb, &secattr, sid);
158 *type = secattr.type;
159 netlbl_secattr_destroy(&secattr);
165 * selinux_netlbl_sock_graft - Netlabel the new socket
166 * @sk: the new connection
167 * @sock: the new socket
170 * The connection represented by @sk is being grafted onto @sock so set the
171 * socket's NetLabel to match the SID of @sk.
174 void selinux_netlbl_sock_graft(struct sock *sk, struct socket *sock)
176 struct sk_security_struct *sksec = sk->sk_security;
177 struct netlbl_lsm_secattr secattr;
180 if (sksec->nlbl_state != NLBL_REQUIRE)
183 netlbl_secattr_init(&secattr);
184 if (netlbl_sock_getattr(sk, &secattr) == 0 &&
185 secattr.flags != NETLBL_SECATTR_NONE &&
186 security_netlbl_secattr_to_sid(&secattr, &nlbl_peer_sid) == 0)
187 sksec->peer_sid = nlbl_peer_sid;
188 netlbl_secattr_destroy(&secattr);
190 /* Try to set the NetLabel on the socket to save time later, if we fail
191 * here we will pick up the pieces in later calls to
192 * selinux_netlbl_inode_permission(). */
193 selinux_netlbl_sock_setsid(sk, sksec->sid);
197 * selinux_netlbl_socket_post_create - Label a socket using NetLabel
198 * @sock: the socket to label
201 * Attempt to label a socket using the NetLabel mechanism using the given
202 * SID. Returns zero values on success, negative values on failure.
205 int selinux_netlbl_socket_post_create(struct socket *sock)
207 struct sock *sk = sock->sk;
208 struct sk_security_struct *sksec = sk->sk_security;
210 if (sksec->nlbl_state != NLBL_REQUIRE)
213 return selinux_netlbl_sock_setsid(sk, sksec->sid);
217 * selinux_netlbl_inode_permission - Verify the socket is NetLabel labeled
218 * @inode: the file descriptor's inode
219 * @mask: the permission mask
222 * Looks at a file's inode and if it is marked as a socket protected by
223 * NetLabel then verify that the socket has been labeled, if not try to label
224 * the socket now with the inode's SID. Returns zero on success, negative
228 int selinux_netlbl_inode_permission(struct inode *inode, int mask)
233 struct sk_security_struct *sksec;
235 if (!S_ISSOCK(inode->i_mode) ||
236 ((mask & (MAY_WRITE | MAY_APPEND)) == 0))
239 sock = SOCKET_I(inode);
241 sksec = sk->sk_security;
242 if (sksec->nlbl_state != NLBL_REQUIRE)
246 bh_lock_sock_nested(sk);
247 if (likely(sksec->nlbl_state == NLBL_REQUIRE))
248 rc = selinux_netlbl_sock_setsid(sk, sksec->sid);
258 * selinux_netlbl_sock_rcv_skb - Do an inbound access check using NetLabel
259 * @sksec: the sock's sk_security_struct
261 * @family: protocol family
262 * @ad: the audit data
265 * Fetch the NetLabel security attributes from @skb and perform an access check
266 * against the receiving socket. Returns zero on success, negative values on
270 int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec,
273 struct avc_audit_data *ad)
278 struct netlbl_lsm_secattr secattr;
280 if (!netlbl_enabled())
283 netlbl_secattr_init(&secattr);
284 rc = netlbl_skbuff_getattr(skb, family, &secattr);
285 if (rc == 0 && secattr.flags != NETLBL_SECATTR_NONE)
286 rc = selinux_netlbl_sidlookup_cached(skb, &secattr, &nlbl_sid);
288 nlbl_sid = SECINITSID_UNLABELED;
289 netlbl_secattr_destroy(&secattr);
293 switch (sksec->sclass) {
294 case SECCLASS_UDP_SOCKET:
295 perm = UDP_SOCKET__RECVFROM;
297 case SECCLASS_TCP_SOCKET:
298 perm = TCP_SOCKET__RECVFROM;
301 perm = RAWIP_SOCKET__RECVFROM;
304 rc = avc_has_perm(sksec->sid, nlbl_sid, sksec->sclass, perm, ad);
308 if (nlbl_sid != SECINITSID_UNLABELED)
309 netlbl_skbuff_err(skb, rc);
314 * selinux_netlbl_socket_setsockopt - Do not allow users to remove a NetLabel
316 * @level: the socket level or protocol
317 * @optname: the socket option name
320 * Check the setsockopt() call and if the user is trying to replace the IP
321 * options on a socket and a NetLabel is in place for the socket deny the
322 * access; otherwise allow the access. Returns zero when the access is
323 * allowed, -EACCES when denied, and other negative values on error.
326 int selinux_netlbl_socket_setsockopt(struct socket *sock,
331 struct sock *sk = sock->sk;
332 struct sk_security_struct *sksec = sk->sk_security;
333 struct netlbl_lsm_secattr secattr;
335 if (level == IPPROTO_IP && optname == IP_OPTIONS &&
336 sksec->nlbl_state == NLBL_LABELED) {
337 netlbl_secattr_init(&secattr);
339 rc = netlbl_sock_getattr(sk, &secattr);
341 if (rc == 0 && secattr.flags != NETLBL_SECATTR_NONE)
343 netlbl_secattr_destroy(&secattr);