[linux-2.6-block.git] / security / selinux / netlabel.c

/*
 * SELinux NetLabel Support
 *
 * This file provides the necessary glue to tie NetLabel into the SELinux
 * subsystem.
 *
 * Author: Paul Moore <paul@paul-moore.com>
 *
 */

/*
 * (c) Copyright Hewlett-Packard Development Company, L.P., 2007, 2008
 *
 * This program is free software;  you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY;  without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 * the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program;  if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 */

#include <linux/spinlock.h>
#include <linux/rcupdate.h>
#include <linux/gfp.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <net/sock.h>
#include <net/netlabel.h>
#include <net/ip.h>
#include <net/ipv6.h>

#include "objsec.h"
#include "security.h"
#include "netlabel.h"

/**
 * selinux_netlbl_sidlookup_cached - Cache a SID lookup
 * @skb: the packet
 * @secattr: the NetLabel security attributes
 * @sid: the SID
 *
 * Description:
 * Query the SELinux security server to lookup the correct SID for the given
 * security attributes.  If the query is successful, cache the result to speed
 * up future lookups.  Returns zero on success, negative values on failure.
 *
 */
static int selinux_netlbl_sidlookup_cached(struct sk_buff *skb,
					   struct netlbl_lsm_secattr *secattr,
					   u32 *sid)
{
	int rc;

	rc = security_netlbl_secattr_to_sid(secattr, sid);
	if (rc == 0 &&
	    (secattr->flags & NETLBL_SECATTR_CACHEABLE) &&
	    (secattr->flags & NETLBL_SECATTR_CACHE))
		netlbl_cache_add(skb, secattr);

	return rc;
}

/**
 * selinux_netlbl_sock_genattr - Generate the NetLabel socket secattr
 * @sk: the socket
 *
 * Description:
 * Generate the NetLabel security attributes for a socket, making full use of
 * the socket's attribute cache.  Returns a pointer to the security attributes
 * on success, NULL on failure.
 *
 */
static struct netlbl_lsm_secattr *selinux_netlbl_sock_genattr(struct sock *sk)
{
	int rc;
	struct sk_security_struct *sksec = sk->sk_security;
	struct netlbl_lsm_secattr *secattr;

	if (sksec->nlbl_secattr != NULL)
		return sksec->nlbl_secattr;

	secattr = netlbl_secattr_alloc(GFP_ATOMIC);
	if (secattr == NULL)
		return NULL;
	rc = security_netlbl_sid_to_secattr(sksec->sid, secattr);
	if (rc != 0) {
		netlbl_secattr_free(secattr);
		return NULL;
	}
	sksec->nlbl_secattr = secattr;

	return secattr;
}

/**
 * selinux_netlbl_sock_getattr - Get the cached NetLabel secattr
 * @sk: the socket
 * @sid: the SID
 *
 * Query the socket's cached secattr and if the SID matches the cached value
 * return the cache, otherwise return NULL.
 *
 */
static struct netlbl_lsm_secattr *selinux_netlbl_sock_getattr(
							const struct sock *sk,
							u32 sid)
{
	struct sk_security_struct *sksec = sk->sk_security;
	struct netlbl_lsm_secattr *secattr = sksec->nlbl_secattr;

	if (secattr == NULL)
		return NULL;

	if ((secattr->flags & NETLBL_SECATTR_SECID) &&
	    (secattr->attr.secid == sid))
		return secattr;

	return NULL;
}

/**
 * selinux_netlbl_cache_invalidate - Invalidate the NetLabel cache
 *
 * Description:
 * Invalidate the NetLabel security attribute mapping cache.
 *
 */
void selinux_netlbl_cache_invalidate(void)
{
	netlbl_cache_invalidate();
}

/**
 * selinux_netlbl_err - Handle a NetLabel packet error
 * @skb: the packet
 * @error: the error code
 * @gateway: true if host is acting as a gateway, false otherwise
 *
 * Description:
 * When a packet is dropped due to a call to avc_has_perm() pass the error
 * code to the NetLabel subsystem so any protocol specific processing can be
 * done.  This is safe to call even if you are unsure if NetLabel labeling is
 * present on the packet, NetLabel is smart enough to only act when it should.
 *
 */
void selinux_netlbl_err(struct sk_buff *skb, int error, int gateway)
{
	netlbl_skbuff_err(skb, error, gateway);
}

/**
 * selinux_netlbl_sk_security_free - Free the NetLabel fields
 * @sksec: the sk_security_struct
 *
 * Description:
 * Free all of the memory in the NetLabel fields of a sk_security_struct.
 *
 */
void selinux_netlbl_sk_security_free(struct sk_security_struct *sksec)
{
	if (sksec->nlbl_secattr != NULL)
		netlbl_secattr_free(sksec->nlbl_secattr);
}

/**
 * selinux_netlbl_sk_security_reset - Reset the NetLabel fields
 * @sksec: the sk_security_struct
 * @family: the socket family
 *
 * Description:
 * Called when the NetLabel state of a sk_security_struct needs to be reset.
 * The caller is responsible for all the NetLabel sk_security_struct locking.
 *
 */
void selinux_netlbl_sk_security_reset(struct sk_security_struct *sksec)
{
	sksec->nlbl_state = NLBL_UNSET;
}

/**
 * selinux_netlbl_skbuff_getsid - Get the sid of a packet using NetLabel
 * @skb: the packet
 * @family: protocol family
 * @type: NetLabel labeling protocol type
 * @sid: the SID
 *
 * Description:
 * Call the NetLabel mechanism to get the security attributes of the given
 * packet and use those attributes to determine the correct context/SID to
 * assign to the packet.  Returns zero on success, negative values on failure.
 *
 */
int selinux_netlbl_skbuff_getsid(struct sk_buff *skb,
				 u16 family,
				 u32 *type,
				 u32 *sid)
{
	int rc;
	struct netlbl_lsm_secattr secattr;

	if (!netlbl_enabled()) {
		*sid = SECSID_NULL;
		return 0;
	}

	netlbl_secattr_init(&secattr);
	rc = netlbl_skbuff_getattr(skb, family, &secattr);
	if (rc == 0 && secattr.flags != NETLBL_SECATTR_NONE)
		rc = selinux_netlbl_sidlookup_cached(skb, &secattr, sid);
	else
		*sid = SECSID_NULL;
	*type = secattr.type;
	netlbl_secattr_destroy(&secattr);

	return rc;
}

/**
 * selinux_netlbl_skbuff_setsid - Set the NetLabel on a packet given a sid
 * @skb: the packet
 * @family: protocol family
 * @sid: the SID
 *
 * Description
 * Call the NetLabel mechanism to set the label of a packet using @sid.
 * Returns zero on success, negative values on failure.
 *
 */
int selinux_netlbl_skbuff_setsid(struct sk_buff *skb,
				 u16 family,
				 u32 sid)
{
	int rc;
	struct netlbl_lsm_secattr secattr_storage;
	struct netlbl_lsm_secattr *secattr = NULL;
	struct sock *sk;

	/* if this is a locally generated packet check to see if it is already
	 * being labeled by it's parent socket, if it is just exit */
	sk = skb->sk;
	if (sk != NULL) {
		struct sk_security_struct *sksec = sk->sk_security;
		if (sksec->nlbl_state != NLBL_REQSKB)
			return 0;
		secattr = selinux_netlbl_sock_getattr(sk, sid);
	}
	if (secattr == NULL) {
		secattr = &secattr_storage;
		netlbl_secattr_init(secattr);
		rc = security_netlbl_sid_to_secattr(sid, secattr);
		if (rc != 0)
			goto skbuff_setsid_return;
	}

	rc = netlbl_skbuff_setattr(skb, family, secattr);

skbuff_setsid_return:
	if (secattr == &secattr_storage)
		netlbl_secattr_destroy(secattr);
	return rc;
}

/**
 * selinux_netlbl_inet_conn_request - Label an incoming stream connection
 * @req: incoming connection request socket
 *
 * Description:
 * A new incoming connection request is represented by @req, we need to label
 * the new request_sock here and the stack will ensure the on-the-wire label
 * will get preserved when a full sock is created once the connection handshake
 * is complete.  Returns zero on success, negative values on failure.
 *
 */
int selinux_netlbl_inet_conn_request(struct request_sock *req, u16 family)
{
	int rc;
	struct netlbl_lsm_secattr secattr;

	if (family != PF_INET)
		return 0;

	netlbl_secattr_init(&secattr);
	rc = security_netlbl_sid_to_secattr(req->secid, &secattr);
	if (rc != 0)
		goto inet_conn_request_return;
	rc = netlbl_req_setattr(req, &secattr);
inet_conn_request_return:
	netlbl_secattr_destroy(&secattr);
	return rc;
}

/**
 * selinux_netlbl_inet_csk_clone - Initialize the newly created sock
 * @sk: the new sock
 *
 * Description:
 * A new connection has been established using @sk, we've already labeled the
 * socket via the request_sock struct in selinux_netlbl_inet_conn_request() but
 * we need to set the NetLabel state here since we now have a sock structure.
 *
 */
void selinux_netlbl_inet_csk_clone(struct sock *sk, u16 family)
{
	struct sk_security_struct *sksec = sk->sk_security;

	if (family == PF_INET)
		sksec->nlbl_state = NLBL_LABELED;
	else
		sksec->nlbl_state = NLBL_UNSET;
}

/**
 * selinux_netlbl_socket_post_create - Label a socket using NetLabel
 * @sock: the socket to label
 * @family: protocol family
 *
 * Description:
 * Attempt to label a socket using the NetLabel mechanism using the given
 * SID.  Returns zero values on success, negative values on failure.
 *
 */
int selinux_netlbl_socket_post_create(struct sock *sk, u16 family)
{
	int rc;
	struct sk_security_struct *sksec = sk->sk_security;
	struct netlbl_lsm_secattr *secattr;

	if (family != PF_INET)
		return 0;

	secattr = selinux_netlbl_sock_genattr(sk);
	if (secattr == NULL)
		return -ENOMEM;
	rc = netlbl_sock_setattr(sk, family, secattr);
	switch (rc) {
	case 0:
		sksec->nlbl_state = NLBL_LABELED;
		break;
	case -EDESTADDRREQ:
		sksec->nlbl_state = NLBL_REQSKB;
		rc = 0;
		break;
	}

	return rc;
}

/**
 * selinux_netlbl_sock_rcv_skb - Do an inbound access check using NetLabel
 * @sksec: the sock's sk_security_struct
 * @skb: the packet
 * @family: protocol family
 * @ad: the audit data
 *
 * Description:
 * Fetch the NetLabel security attributes from @skb and perform an access check
 * against the receiving socket.  Returns zero on success, negative values on
 * error.
 *
 */
int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec,
				struct sk_buff *skb,
				u16 family,
				struct common_audit_data *ad)
{
	int rc;
	u32 nlbl_sid;
	u32 perm;
	struct netlbl_lsm_secattr secattr;

	if (!netlbl_enabled())
		return 0;

	netlbl_secattr_init(&secattr);
	rc = netlbl_skbuff_getattr(skb, family, &secattr);
	if (rc == 0 && secattr.flags != NETLBL_SECATTR_NONE)
		rc = selinux_netlbl_sidlookup_cached(skb, &secattr, &nlbl_sid);
	else
		nlbl_sid = SECINITSID_UNLABELED;
	netlbl_secattr_destroy(&secattr);
	if (rc != 0)
		return rc;

	switch (sksec->sclass) {
	case SECCLASS_UDP_SOCKET:
		perm = UDP_SOCKET__RECVFROM;
		break;
	case SECCLASS_TCP_SOCKET:
		perm = TCP_SOCKET__RECVFROM;
		break;
	default:
		perm = RAWIP_SOCKET__RECVFROM;
	}

	rc = avc_has_perm(sksec->sid, nlbl_sid, sksec->sclass, perm, ad);
	if (rc == 0)
		return 0;

	if (nlbl_sid != SECINITSID_UNLABELED)
		netlbl_skbuff_err(skb, rc, 0);
	return rc;
}

/**
 * selinux_netlbl_socket_setsockopt - Do not allow users to remove a NetLabel
 * @sock: the socket
 * @level: the socket level or protocol
 * @optname: the socket option name
 *
 * Description:
 * Check the setsockopt() call and if the user is trying to replace the IP
 * options on a socket and a NetLabel is in place for the socket deny the
 * access; otherwise allow the access.  Returns zero when the access is
 * allowed, -EACCES when denied, and other negative values on error.
 *
 */
int selinux_netlbl_socket_setsockopt(struct socket *sock,
				     int level,
				     int optname)
{
	int rc = 0;
	struct sock *sk = sock->sk;
	struct sk_security_struct *sksec = sk->sk_security;
	struct netlbl_lsm_secattr secattr;

	if (level == IPPROTO_IP && optname == IP_OPTIONS &&
	    (sksec->nlbl_state == NLBL_LABELED ||
	     sksec->nlbl_state == NLBL_CONNLABELED)) {
		netlbl_secattr_init(&secattr);
		lock_sock(sk);
		/* call the netlabel function directly as we want to see the
		 * on-the-wire label that is assigned via the socket's options
		 * and not the cached netlabel/lsm attributes */
		rc = netlbl_sock_getattr(sk, &secattr);
		release_sock(sk);
		if (rc == 0)
			rc = -EACCES;
		else if (rc == -ENOMSG)
			rc = 0;
		netlbl_secattr_destroy(&secattr);
	}

	return rc;
}

/**
 * selinux_netlbl_socket_connect - Label a client-side socket on connect
 * @sk: the socket to label
 * @addr: the destination address
 *
 * Description:
 * Attempt to label a connected socket with NetLabel using the given address.
 * Returns zero values on success, negative values on failure.
 *
 */
int selinux_netlbl_socket_connect(struct sock *sk, struct sockaddr *addr)
{
	int rc;
	struct sk_security_struct *sksec = sk->sk_security;
	struct netlbl_lsm_secattr *secattr;

	if (sksec->nlbl_state != NLBL_REQSKB &&
	    sksec->nlbl_state != NLBL_CONNLABELED)
		return 0;

	lock_sock(sk);

	/* connected sockets are allowed to disconnect when the address family
	 * is set to AF_UNSPEC, if that is what is happening we want to reset
	 * the socket */
	if (addr->sa_family == AF_UNSPEC) {
		netlbl_sock_delattr(sk);
		sksec->nlbl_state = NLBL_REQSKB;
		rc = 0;
		goto socket_connect_return;
	}
	secattr = selinux_netlbl_sock_genattr(sk);
	if (secattr == NULL) {
		rc = -ENOMEM;
		goto socket_connect_return;
	}
	rc = netlbl_conn_setattr(sk, addr, secattr);
	if (rc == 0)
		sksec->nlbl_state = NLBL_CONNLABELED;

socket_connect_return:
	release_sock(sk);
	return rc;
}
Commit	Line	Data
5778eabd PM	1	/*
	2	* SELinux NetLabel Support
	3	*
	4	* This file provides the necessary glue to tie NetLabel into the SELinux
	5	* subsystem.
	6	*
82c21bfa	7	* Author: Paul Moore <paul@paul-moore.com>
5778eabd PM	8	*
	9	*/
	10
	11	/*
948bf85c	12	* (c) Copyright Hewlett-Packard Development Company, L.P., 2007, 2008
5778eabd PM	13	*
	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.
	18	*
	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.
	23	*
	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
	27	*
	28	*/
	29
	30	#include <linux/spinlock.h>
	31	#include <linux/rcupdate.h>
5a0e3ad6	32	#include <linux/gfp.h>
014ab19a PM	33	#include <linux/ip.h>
014ab19a PM	34	#include <linux/ipv6.h>
5778eabd PM	35	#include <net/sock.h>
5778eabd PM	36	#include <net/netlabel.h>
014ab19a PM	37	#include <net/ip.h>
014ab19a PM	38	#include <net/ipv6.h>
5778eabd PM	39
	40	#include "objsec.h"
	41	#include "security.h"
d4ee4231	42	#include "netlabel.h"
5778eabd	43
5dbe1eb0 PM	44	/**
	45	* selinux_netlbl_sidlookup_cached - Cache a SID lookup
	46	* @skb: the packet
	47	* @secattr: the NetLabel security attributes
	48	* @sid: the SID
	49	*
	50	* Description:
	51	* Query the SELinux security server to lookup the correct SID for the given
	52	* security attributes. If the query is successful, cache the result to speed
	53	* up future lookups. Returns zero on success, negative values on failure.
	54	*
	55	*/
	56	static int selinux_netlbl_sidlookup_cached(struct sk_buff *skb,
	57	struct netlbl_lsm_secattr *secattr,
	58	u32 *sid)
	59	{
	60	int rc;
	61
	62	rc = security_netlbl_secattr_to_sid(secattr, sid);
	63	if (rc == 0 &&
	64	(secattr->flags & NETLBL_SECATTR_CACHEABLE) &&
	65	(secattr->flags & NETLBL_SECATTR_CACHE))
	66	netlbl_cache_add(skb, secattr);
	67
	68	return rc;
	69	}
	70
6c5b3fc0 PM	71	/**
	72	* selinux_netlbl_sock_genattr - Generate the NetLabel socket secattr
	73	* @sk: the socket
	74	*
	75	* Description:
	76	* Generate the NetLabel security attributes for a socket, making full use of
	77	* the socket's attribute cache. Returns a pointer to the security attributes
	78	* on success, NULL on failure.
	79	*
	80	*/
	81	static struct netlbl_lsm_secattr selinux_netlbl_sock_genattr(struct sock sk)
	82	{
	83	int rc;
	84	struct sk_security_struct *sksec = sk->sk_security;
	85	struct netlbl_lsm_secattr *secattr;
	86
	87	if (sksec->nlbl_secattr != NULL)
	88	return sksec->nlbl_secattr;
	89
	90	secattr = netlbl_secattr_alloc(GFP_ATOMIC);
	91	if (secattr == NULL)
	92	return NULL;
	93	rc = security_netlbl_sid_to_secattr(sksec->sid, secattr);
	94	if (rc != 0) {
	95	netlbl_secattr_free(secattr);
	96	return NULL;
	97	}
	98	sksec->nlbl_secattr = secattr;
	99
	100	return secattr;
	101	}
	102
050d032b PM	103	/**
	104	* selinux_netlbl_sock_getattr - Get the cached NetLabel secattr
	105	* @sk: the socket
	106	* @sid: the SID
	107	*
	108	* Query the socket's cached secattr and if the SID matches the cached value
	109	* return the cache, otherwise return NULL.
	110	*
	111	*/
	112	static struct netlbl_lsm_secattr *selinux_netlbl_sock_getattr(
	113	const struct sock *sk,
	114	u32 sid)
	115	{
	116	struct sk_security_struct *sksec = sk->sk_security;
	117	struct netlbl_lsm_secattr *secattr = sksec->nlbl_secattr;
	118
	119	if (secattr == NULL)
	120	return NULL;
	121
	122	if ((secattr->flags & NETLBL_SECATTR_SECID) &&
	123	(secattr->attr.secid == sid))
	124	return secattr;
	125
	126	return NULL;
	127	}
	128
5778eabd PM	129	/**
	130	* selinux_netlbl_cache_invalidate - Invalidate the NetLabel cache
	131	*
	132	* Description:
	133	* Invalidate the NetLabel security attribute mapping cache.
	134	*
	135	*/
	136	void selinux_netlbl_cache_invalidate(void)
	137	{
	138	netlbl_cache_invalidate();
	139	}
	140
dfaebe98 PM	141	/**
	142	* selinux_netlbl_err - Handle a NetLabel packet error
	143	* @skb: the packet
	144	* @error: the error code
	145	* @gateway: true if host is acting as a gateway, false otherwise
	146	*
	147	* Description:
	148	* When a packet is dropped due to a call to avc_has_perm() pass the error
	149	* code to the NetLabel subsystem so any protocol specific processing can be
	150	* done. This is safe to call even if you are unsure if NetLabel labeling is
	151	* present on the packet, NetLabel is smart enough to only act when it should.
	152	*
	153	*/
	154	void selinux_netlbl_err(struct sk_buff *skb, int error, int gateway)
	155	{
	156	netlbl_skbuff_err(skb, error, gateway);
	157	}
	158
6c5b3fc0 PM	159	/**
6c5b3fc0 PM	160	* selinux_netlbl_sk_security_free - Free the NetLabel fields
dd3e7836	161	* @sksec: the sk_security_struct
6c5b3fc0 PM	162	*
	163	* Description:
	164	* Free all of the memory in the NetLabel fields of a sk_security_struct.
	165	*
	166	*/
dd3e7836	167	void selinux_netlbl_sk_security_free(struct sk_security_struct *sksec)
6c5b3fc0	168	{
dd3e7836 EP	169	if (sksec->nlbl_secattr != NULL)
dd3e7836 EP	170	netlbl_secattr_free(sksec->nlbl_secattr);
6c5b3fc0 PM	171	}
6c5b3fc0 PM	172
5778eabd PM	173	/**
5778eabd PM	174	* selinux_netlbl_sk_security_reset - Reset the NetLabel fields
dd3e7836	175	* @sksec: the sk_security_struct
5778eabd PM	176	* @family: the socket family
	177	*
	178	* Description:
	179	* Called when the NetLabel state of a sk_security_struct needs to be reset.
25985edc	180	* The caller is responsible for all the NetLabel sk_security_struct locking.
5778eabd PM	181	*
5778eabd PM	182	*/
dd3e7836	183	void selinux_netlbl_sk_security_reset(struct sk_security_struct *sksec)
5778eabd	184	{
dd3e7836	185	sksec->nlbl_state = NLBL_UNSET;
5778eabd PM	186	}
5778eabd PM	187
5778eabd PM	188	/**
	189	* selinux_netlbl_skbuff_getsid - Get the sid of a packet using NetLabel
	190	* @skb: the packet
75e22910	191	* @family: protocol family
220deb96	192	* @type: NetLabel labeling protocol type
5778eabd PM	193	* @sid: the SID
	194	*
	195	* Description:
	196	* Call the NetLabel mechanism to get the security attributes of the given
	197	* packet and use those attributes to determine the correct context/SID to
	198	* assign to the packet. Returns zero on success, negative values on failure.
	199	*
	200	*/
75e22910 PM	201	int selinux_netlbl_skbuff_getsid(struct sk_buff *skb,
75e22910 PM	202	u16 family,
220deb96	203	u32 *type,
75e22910	204	u32 *sid)
5778eabd PM	205	{
	206	int rc;
	207	struct netlbl_lsm_secattr secattr;
	208
23bcdc1a PM	209	if (!netlbl_enabled()) {
	210	*sid = SECSID_NULL;
	211	return 0;
	212	}
	213
5778eabd	214	netlbl_secattr_init(&secattr);
75e22910	215	rc = netlbl_skbuff_getattr(skb, family, &secattr);
5dbe1eb0 PM	216	if (rc == 0 && secattr.flags != NETLBL_SECATTR_NONE)
	217	rc = selinux_netlbl_sidlookup_cached(skb, &secattr, sid);
	218	else
5778eabd	219	*sid = SECSID_NULL;
220deb96	220	*type = secattr.type;
5778eabd PM	221	netlbl_secattr_destroy(&secattr);
	222
	223	return rc;
	224	}
	225
948bf85c PM	226	/**
	227	* selinux_netlbl_skbuff_setsid - Set the NetLabel on a packet given a sid
	228	* @skb: the packet
	229	* @family: protocol family
	230	* @sid: the SID
	231	*
	232	* Description
	233	* Call the NetLabel mechanism to set the label of a packet using @sid.
af901ca1	234	* Returns zero on success, negative values on failure.
948bf85c PM	235	*
	236	*/
	237	int selinux_netlbl_skbuff_setsid(struct sk_buff *skb,
	238	u16 family,
	239	u32 sid)
	240	{
	241	int rc;
6c5b3fc0 PM	242	struct netlbl_lsm_secattr secattr_storage;
6c5b3fc0 PM	243	struct netlbl_lsm_secattr *secattr = NULL;
948bf85c PM	244	struct sock *sk;
	245
	246	/* if this is a locally generated packet check to see if it is already
	247	* being labeled by it's parent socket, if it is just exit */
	248	sk = skb->sk;
	249	if (sk != NULL) {
	250	struct sk_security_struct *sksec = sk->sk_security;
	251	if (sksec->nlbl_state != NLBL_REQSKB)
	252	return 0;
050d032b	253	secattr = selinux_netlbl_sock_getattr(sk, sid);
6c5b3fc0 PM	254	}
	255	if (secattr == NULL) {
	256	secattr = &secattr_storage;
	257	netlbl_secattr_init(secattr);
	258	rc = security_netlbl_sid_to_secattr(sid, secattr);
	259	if (rc != 0)
	260	goto skbuff_setsid_return;
948bf85c PM	261	}
948bf85c PM	262
6c5b3fc0	263	rc = netlbl_skbuff_setattr(skb, family, secattr);
948bf85c PM	264
948bf85c PM	265	skbuff_setsid_return:
6c5b3fc0 PM	266	if (secattr == &secattr_storage)
6c5b3fc0 PM	267	netlbl_secattr_destroy(secattr);
948bf85c PM	268	return rc;
	269	}
	270
5778eabd	271	/**
389fb800 PM	272	* selinux_netlbl_inet_conn_request - Label an incoming stream connection
389fb800 PM	273	* @req: incoming connection request socket
5778eabd PM	274	*
5778eabd PM	275	* Description:
389fb800 PM	276	* A new incoming connection request is represented by @req, we need to label
	277	* the new request_sock here and the stack will ensure the on-the-wire label
	278	* will get preserved when a full sock is created once the connection handshake
	279	* is complete. Returns zero on success, negative values on failure.
5778eabd PM	280	*
5778eabd PM	281	*/
389fb800	282	int selinux_netlbl_inet_conn_request(struct request_sock *req, u16 family)
5778eabd	283	{
014ab19a	284	int rc;
389fb800	285	struct netlbl_lsm_secattr secattr;
014ab19a	286
389fb800 PM	287	if (family != PF_INET)
389fb800 PM	288	return 0;
014ab19a	289
389fb800 PM	290	netlbl_secattr_init(&secattr);
	291	rc = security_netlbl_sid_to_secattr(req->secid, &secattr);
	292	if (rc != 0)
	293	goto inet_conn_request_return;
	294	rc = netlbl_req_setattr(req, &secattr);
	295	inet_conn_request_return:
	296	netlbl_secattr_destroy(&secattr);
	297	return rc;
5778eabd PM	298	}
	299
	300	/**
389fb800 PM	301	* selinux_netlbl_inet_csk_clone - Initialize the newly created sock
389fb800 PM	302	* @sk: the new sock
5778eabd PM	303	*
5778eabd PM	304	* Description:
389fb800 PM	305	* A new connection has been established using @sk, we've already labeled the
	306	* socket via the request_sock struct in selinux_netlbl_inet_conn_request() but
	307	* we need to set the NetLabel state here since we now have a sock structure.
5778eabd PM	308	*
5778eabd PM	309	*/
389fb800	310	void selinux_netlbl_inet_csk_clone(struct sock *sk, u16 family)
5778eabd	311	{
389fb800 PM	312	struct sk_security_struct *sksec = sk->sk_security;
	313
	314	if (family == PF_INET)
	315	sksec->nlbl_state = NLBL_LABELED;
	316	else
	317	sksec->nlbl_state = NLBL_UNSET;
5778eabd PM	318	}
	319
	320	/**
389fb800 PM	321	* selinux_netlbl_socket_post_create - Label a socket using NetLabel
	322	* @sock: the socket to label
	323	* @family: protocol family
5778eabd PM	324	*
5778eabd PM	325	* Description:
389fb800 PM	326	* Attempt to label a socket using the NetLabel mechanism using the given
389fb800 PM	327	* SID. Returns zero values on success, negative values on failure.
5778eabd PM	328	*
5778eabd PM	329	*/
389fb800	330	int selinux_netlbl_socket_post_create(struct sock *sk, u16 family)
5778eabd PM	331	{
5778eabd PM	332	int rc;
389fb800 PM	333	struct sk_security_struct *sksec = sk->sk_security;
389fb800 PM	334	struct netlbl_lsm_secattr *secattr;
5778eabd	335
389fb800	336	if (family != PF_INET)
5778eabd	337	return 0;
f74af6e8	338
389fb800 PM	339	secattr = selinux_netlbl_sock_genattr(sk);
	340	if (secattr == NULL)
	341	return -ENOMEM;
	342	rc = netlbl_sock_setattr(sk, family, secattr);
	343	switch (rc) {
	344	case 0:
	345	sksec->nlbl_state = NLBL_LABELED;
	346	break;
	347	case -EDESTADDRREQ:
	348	sksec->nlbl_state = NLBL_REQSKB;
f74af6e8	349	rc = 0;
389fb800 PM	350	break;
389fb800 PM	351	}
5778eabd PM	352
	353	return rc;
	354	}
	355
	356	/**
	357	* selinux_netlbl_sock_rcv_skb - Do an inbound access check using NetLabel
	358	* @sksec: the sock's sk_security_struct
	359	* @skb: the packet
75e22910	360	* @family: protocol family
5778eabd PM	361	* @ad: the audit data
	362	*
	363	* Description:
	364	* Fetch the NetLabel security attributes from @skb and perform an access check
	365	* against the receiving socket. Returns zero on success, negative values on
	366	* error.
	367	*
	368	*/
	369	int selinux_netlbl_sock_rcv_skb(struct sk_security_struct *sksec,
	370	struct sk_buff *skb,
75e22910	371	u16 family,
2bf49690	372	struct common_audit_data *ad)
5778eabd PM	373	{
5778eabd PM	374	int rc;
f36158c4 PM	375	u32 nlbl_sid;
	376	u32 perm;
	377	struct netlbl_lsm_secattr secattr;
5778eabd	378
23bcdc1a PM	379	if (!netlbl_enabled())
	380	return 0;
	381
f36158c4	382	netlbl_secattr_init(&secattr);
75e22910	383	rc = netlbl_skbuff_getattr(skb, family, &secattr);
5dbe1eb0 PM	384	if (rc == 0 && secattr.flags != NETLBL_SECATTR_NONE)
	385	rc = selinux_netlbl_sidlookup_cached(skb, &secattr, &nlbl_sid);
	386	else
f36158c4 PM	387	nlbl_sid = SECINITSID_UNLABELED;
f36158c4 PM	388	netlbl_secattr_destroy(&secattr);
5778eabd PM	389	if (rc != 0)
5778eabd PM	390	return rc;
8d9107e8	391
5778eabd PM	392	switch (sksec->sclass) {
5778eabd PM	393	case SECCLASS_UDP_SOCKET:
f36158c4	394	perm = UDP_SOCKET__RECVFROM;
5778eabd PM	395	break;
5778eabd PM	396	case SECCLASS_TCP_SOCKET:
f36158c4	397	perm = TCP_SOCKET__RECVFROM;
5778eabd PM	398	break;
5778eabd PM	399	default:
f36158c4	400	perm = RAWIP_SOCKET__RECVFROM;
5778eabd PM	401	}
5778eabd PM	402
f36158c4	403	rc = avc_has_perm(sksec->sid, nlbl_sid, sksec->sclass, perm, ad);
5778eabd PM	404	if (rc == 0)
	405	return 0;
	406
f36158c4	407	if (nlbl_sid != SECINITSID_UNLABELED)
dfaebe98	408	netlbl_skbuff_err(skb, rc, 0);
5778eabd PM	409	return rc;
	410	}
	411
	412	/**
	413	* selinux_netlbl_socket_setsockopt - Do not allow users to remove a NetLabel
	414	* @sock: the socket
	415	* @level: the socket level or protocol
	416	* @optname: the socket option name
	417	*
	418	* Description:
	419	* Check the setsockopt() call and if the user is trying to replace the IP
	420	* options on a socket and a NetLabel is in place for the socket deny the
	421	* access; otherwise allow the access. Returns zero when the access is
	422	* allowed, -EACCES when denied, and other negative values on error.
	423	*
	424	*/
	425	int selinux_netlbl_socket_setsockopt(struct socket *sock,
	426	int level,
	427	int optname)
	428	{
	429	int rc = 0;
ba6ff9f2 PM	430	struct sock *sk = sock->sk;
ba6ff9f2 PM	431	struct sk_security_struct *sksec = sk->sk_security;
5778eabd PM	432	struct netlbl_lsm_secattr secattr;
5778eabd PM	433
5778eabd	434	if (level == IPPROTO_IP && optname == IP_OPTIONS &&
014ab19a PM	435	(sksec->nlbl_state == NLBL_LABELED \|\|
014ab19a PM	436	sksec->nlbl_state == NLBL_CONNLABELED)) {
5778eabd	437	netlbl_secattr_init(&secattr);
ba6ff9f2	438	lock_sock(sk);
050d032b PM	439	/* call the netlabel function directly as we want to see the
	440	* on-the-wire label that is assigned via the socket's options
	441	* and not the cached netlabel/lsm attributes */
ba6ff9f2 PM	442	rc = netlbl_sock_getattr(sk, &secattr);
ba6ff9f2 PM	443	release_sock(sk);
09c50b4a	444	if (rc == 0)
5778eabd	445	rc = -EACCES;
09c50b4a PM	446	else if (rc == -ENOMSG)
09c50b4a PM	447	rc = 0;
5778eabd PM	448	netlbl_secattr_destroy(&secattr);
5778eabd PM	449	}
5778eabd PM	450
	451	return rc;
	452	}
014ab19a PM	453
	454	/**
	455	* selinux_netlbl_socket_connect - Label a client-side socket on connect
	456	* @sk: the socket to label
	457	* @addr: the destination address
	458	*
	459	* Description:
	460	* Attempt to label a connected socket with NetLabel using the given address.
	461	* Returns zero values on success, negative values on failure.
	462	*
	463	*/
	464	int selinux_netlbl_socket_connect(struct sock sk, struct sockaddr addr)
	465	{
	466	int rc;
	467	struct sk_security_struct *sksec = sk->sk_security;
6c5b3fc0	468	struct netlbl_lsm_secattr *secattr;
014ab19a PM	469
	470	if (sksec->nlbl_state != NLBL_REQSKB &&
	471	sksec->nlbl_state != NLBL_CONNLABELED)
	472	return 0;
	473
42d64e1a	474	lock_sock(sk);
014ab19a PM	475
	476	/* connected sockets are allowed to disconnect when the address family
	477	* is set to AF_UNSPEC, if that is what is happening we want to reset
	478	* the socket */
	479	if (addr->sa_family == AF_UNSPEC) {
	480	netlbl_sock_delattr(sk);
	481	sksec->nlbl_state = NLBL_REQSKB;
	482	rc = 0;
	483	goto socket_connect_return;
	484	}
6c5b3fc0 PM	485	secattr = selinux_netlbl_sock_genattr(sk);
	486	if (secattr == NULL) {
	487	rc = -ENOMEM;
014ab19a	488	goto socket_connect_return;
6c5b3fc0 PM	489	}
	490	rc = netlbl_conn_setattr(sk, addr, secattr);
	491	if (rc == 0)
	492	sksec->nlbl_state = NLBL_CONNLABELED;
014ab19a PM	493
014ab19a PM	494	socket_connect_return:
42d64e1a	495	release_sock(sk);
014ab19a PM	496	return rc;
014ab19a PM	497	}