security/selinux/netlabel.c - kernel/msm-4.9 - Gitiles

 /*
  * 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;
 }
	/*
	* 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;
	}