net/netlabel/netlabel_unlabeled.c - maze/linux - Git at Google

 /*
  * NetLabel Unlabeled Support
  *
  * This file defines functions for dealing with unlabeled packets for the
  * NetLabel system.  The NetLabel system manages static and dynamic label
  * mappings for network protocols such as CIPSO and RIPSO.
  *
  * Author: Paul Moore <paul.moore@hp.com>
  *
  */

 /*
  * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
  *
  * 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/types.h>
 #include <linux/rcupdate.h>
 #include <linux/list.h>
 #include <linux/spinlock.h>
 #include <linux/socket.h>
 #include <linux/string.h>
 #include <linux/skbuff.h>
 #include <net/sock.h>
 #include <net/netlink.h>
 #include <net/genetlink.h>

 #include <net/netlabel.h>
 #include <asm/bug.h>

 #include "netlabel_user.h"
 #include "netlabel_domainhash.h"
 #include "netlabel_unlabeled.h"

 /* Accept unlabeled packets flag */
 static atomic_t netlabel_unlabel_accept_flg = ATOMIC_INIT(0);

 /* NetLabel Generic NETLINK CIPSOv4 family */
 static struct genl_family netlbl_unlabel_gnl_family = {
 	.id = GENL_ID_GENERATE,
 	.hdrsize = 0,
 	.name = NETLBL_NLTYPE_UNLABELED_NAME,
 	.version = NETLBL_PROTO_VERSION,
 	.maxattr = NLBL_UNLABEL_A_MAX,
 };

 /* NetLabel Netlink attribute policy */
 static struct nla_policy netlbl_unlabel_genl_policy[NLBL_UNLABEL_A_MAX + 1] = {
 	[NLBL_UNLABEL_A_ACPTFLG] = { .type = NLA_U8 },
 };

 /*
  * Helper Functions
  */

 /**
  * netlbl_unlabel_acceptflg_set - Set the unlabeled accept flag
  * @value: desired value
  * @audit_secid: the LSM secid to use in the audit message
  *
  * Description:
  * Set the value of the unlabeled accept flag to @value.
  *
  */
 static void netlbl_unlabel_acceptflg_set(u8 value, u32 audit_secid)
 {
 	atomic_set(&netlabel_unlabel_accept_flg, value);
 	netlbl_audit_nomsg((value ?
 			    AUDIT_MAC_UNLBL_ACCEPT : AUDIT_MAC_UNLBL_DENY),
 			   audit_secid);
 }

 /*
  * NetLabel Command Handlers
  */

 /**
  * netlbl_unlabel_accept - Handle an ACCEPT message
  * @skb: the NETLINK buffer
  * @info: the Generic NETLINK info block
  *
  * Description:
  * Process a user generated ACCEPT message and set the accept flag accordingly.
  * Returns zero on success, negative values on failure.
  *
  */
 static int netlbl_unlabel_accept(struct sk_buff *skb, struct genl_info *info)
 {
 	u8 value;

 	if (info->attrs[NLBL_UNLABEL_A_ACPTFLG]) {
 		value = nla_get_u8(info->attrs[NLBL_UNLABEL_A_ACPTFLG]);
 		if (value == 1 || value == 0) {
 			netlbl_unlabel_acceptflg_set(value,
 						     NETLINK_CB(skb).sid);
 			return 0;
 		}
 	}

 	return -EINVAL;
 }

 /**
  * netlbl_unlabel_list - Handle a LIST message
  * @skb: the NETLINK buffer
  * @info: the Generic NETLINK info block
  *
  * Description:
  * Process a user generated LIST message and respond with the current status.
  * Returns zero on success, negative values on failure.
  *
  */
 static int netlbl_unlabel_list(struct sk_buff *skb, struct genl_info *info)
 {
 	int ret_val = -EINVAL;
 	struct sk_buff *ans_skb;
 	void *data;

 	ans_skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
 	if (ans_skb == NULL)
 		goto list_failure;
 	data = netlbl_netlink_hdr_put(ans_skb,
 				      info->snd_pid,
 				      info->snd_seq,
 				      netlbl_unlabel_gnl_family.id,
 				      0,
 				      NLBL_UNLABEL_C_LIST);
 	if (data == NULL) {
 		ret_val = -ENOMEM;
 		goto list_failure;
 	}

 	ret_val = nla_put_u8(ans_skb,
 			     NLBL_UNLABEL_A_ACPTFLG,
 			     atomic_read(&netlabel_unlabel_accept_flg));
 	if (ret_val != 0)
 		goto list_failure;

 	genlmsg_end(ans_skb, data);

 	ret_val = genlmsg_unicast(ans_skb, info->snd_pid);
 	if (ret_val != 0)
 		goto list_failure;
 	return 0;

 list_failure:
 	kfree(ans_skb);
 	return ret_val;
 }


 /*
  * NetLabel Generic NETLINK Command Definitions
  */

 static struct genl_ops netlbl_unlabel_genl_c_accept = {
 	.cmd = NLBL_UNLABEL_C_ACCEPT,
 	.flags = GENL_ADMIN_PERM,
 	.policy = netlbl_unlabel_genl_policy,
 	.doit = netlbl_unlabel_accept,
 	.dumpit = NULL,
 };

 static struct genl_ops netlbl_unlabel_genl_c_list = {
 	.cmd = NLBL_UNLABEL_C_LIST,
 	.flags = 0,
 	.policy = netlbl_unlabel_genl_policy,
 	.doit = netlbl_unlabel_list,
 	.dumpit = NULL,
 };


 /*
  * NetLabel Generic NETLINK Protocol Functions
  */

 /**
  * netlbl_unlabel_genl_init - Register the Unlabeled NetLabel component
  *
  * Description:
  * Register the unlabeled packet NetLabel component with the Generic NETLINK
  * mechanism.  Returns zero on success, negative values on failure.
  *
  */
 int netlbl_unlabel_genl_init(void)
 {
 	int ret_val;

 	ret_val = genl_register_family(&netlbl_unlabel_gnl_family);
 	if (ret_val != 0)
 		return ret_val;

 	ret_val = genl_register_ops(&netlbl_unlabel_gnl_family,
 				    &netlbl_unlabel_genl_c_accept);
 	if (ret_val != 0)
 		return ret_val;

 	ret_val = genl_register_ops(&netlbl_unlabel_gnl_family,
 				    &netlbl_unlabel_genl_c_list);
 	if (ret_val != 0)
 		return ret_val;

 	return 0;
 }

 /*
  * NetLabel KAPI Hooks
  */

 /**
  * netlbl_unlabel_getattr - Get the security attributes for an unlabled packet
  * @secattr: the security attributes
  *
  * Description:
  * Determine the security attributes, if any, for an unlabled packet and return
  * them in @secattr.  Returns zero on success and negative values on failure.
  *
  */
 int netlbl_unlabel_getattr(struct netlbl_lsm_secattr *secattr)
 {
 	if (atomic_read(&netlabel_unlabel_accept_flg) == 1)
 		return netlbl_secattr_init(secattr);

 	return -ENOMSG;
 }

 /**
  * netlbl_unlabel_defconf - Set the default config to allow unlabeled packets
  *
  * Description:
  * Set the default NetLabel configuration to allow incoming unlabeled packets
  * and to send unlabeled network traffic by default.
  *
  */
 int netlbl_unlabel_defconf(void)
 {
 	int ret_val;
 	struct netlbl_dom_map *entry;
 	u32 secid;

 	security_task_getsecid(current, &secid);

 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 	if (entry == NULL)
 		return -ENOMEM;
 	entry->type = NETLBL_NLTYPE_UNLABELED;
 	ret_val = netlbl_domhsh_add_default(entry, secid);
 	if (ret_val != 0)
 		return ret_val;

 	netlbl_unlabel_acceptflg_set(1, secid);

 	return 0;
 }
	/*
	* NetLabel Unlabeled Support
	*
	* This file defines functions for dealing with unlabeled packets for the
	* NetLabel system. The NetLabel system manages static and dynamic label
	* mappings for network protocols such as CIPSO and RIPSO.
	*
	* Author: Paul Moore <paul.moore@hp.com>
	*
	*/

	/*
	* (c) Copyright Hewlett-Packard Development Company, L.P., 2006
	*
	* 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/types.h>
	#include <linux/rcupdate.h>
	#include <linux/list.h>
	#include <linux/spinlock.h>
	#include <linux/socket.h>
	#include <linux/string.h>
	#include <linux/skbuff.h>
	#include <net/sock.h>
	#include <net/netlink.h>
	#include <net/genetlink.h>

	#include <net/netlabel.h>
	#include <asm/bug.h>

	#include "netlabel_user.h"
	#include "netlabel_domainhash.h"
	#include "netlabel_unlabeled.h"

	/* Accept unlabeled packets flag */
	static atomic_t netlabel_unlabel_accept_flg = ATOMIC_INIT(0);

	/* NetLabel Generic NETLINK CIPSOv4 family */
	static struct genl_family netlbl_unlabel_gnl_family = {
	.id = GENL_ID_GENERATE,
	.hdrsize = 0,
	.name = NETLBL_NLTYPE_UNLABELED_NAME,
	.version = NETLBL_PROTO_VERSION,
	.maxattr = NLBL_UNLABEL_A_MAX,
	};

	/* NetLabel Netlink attribute policy */
	static struct nla_policy netlbl_unlabel_genl_policy[NLBL_UNLABEL_A_MAX + 1] = {
	[NLBL_UNLABEL_A_ACPTFLG] = { .type = NLA_U8 },
	};

	/*
	* Helper Functions
	*/

	/**
	* netlbl_unlabel_acceptflg_set - Set the unlabeled accept flag
	* @value: desired value
	* @audit_secid: the LSM secid to use in the audit message
	*
	* Description:
	* Set the value of the unlabeled accept flag to @value.
	*
	*/
	static void netlbl_unlabel_acceptflg_set(u8 value, u32 audit_secid)
	{
	atomic_set(&netlabel_unlabel_accept_flg, value);
	netlbl_audit_nomsg((value ?
	AUDIT_MAC_UNLBL_ACCEPT : AUDIT_MAC_UNLBL_DENY),
	audit_secid);
	}

	/*
	* NetLabel Command Handlers
	*/

	/**
	* netlbl_unlabel_accept - Handle an ACCEPT message
	* @skb: the NETLINK buffer
	* @info: the Generic NETLINK info block
	*
	* Description:
	* Process a user generated ACCEPT message and set the accept flag accordingly.
	* Returns zero on success, negative values on failure.
	*
	*/
	static int netlbl_unlabel_accept(struct sk_buff skb, struct genl_info info)
	{
	u8 value;

	if (info->attrs[NLBL_UNLABEL_A_ACPTFLG]) {
	value = nla_get_u8(info->attrs[NLBL_UNLABEL_A_ACPTFLG]);
	if (value == 1 \|\| value == 0) {
	netlbl_unlabel_acceptflg_set(value,
	NETLINK_CB(skb).sid);
	return 0;
	}
	}

	return -EINVAL;
	}

	/**
	* netlbl_unlabel_list - Handle a LIST message
	* @skb: the NETLINK buffer
	* @info: the Generic NETLINK info block
	*
	* Description:
	* Process a user generated LIST message and respond with the current status.
	* Returns zero on success, negative values on failure.
	*
	*/
	static int netlbl_unlabel_list(struct sk_buff skb, struct genl_info info)
	{
	int ret_val = -EINVAL;
	struct sk_buff *ans_skb;
	void *data;

	ans_skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
	if (ans_skb == NULL)
	goto list_failure;
	data = netlbl_netlink_hdr_put(ans_skb,
	info->snd_pid,
	info->snd_seq,
	netlbl_unlabel_gnl_family.id,
	0,
	NLBL_UNLABEL_C_LIST);
	if (data == NULL) {
	ret_val = -ENOMEM;
	goto list_failure;
	}

	ret_val = nla_put_u8(ans_skb,
	NLBL_UNLABEL_A_ACPTFLG,
	atomic_read(&netlabel_unlabel_accept_flg));
	if (ret_val != 0)
	goto list_failure;

	genlmsg_end(ans_skb, data);

	ret_val = genlmsg_unicast(ans_skb, info->snd_pid);
	if (ret_val != 0)
	goto list_failure;
	return 0;

	list_failure:
	kfree(ans_skb);
	return ret_val;
	}


	/*
	* NetLabel Generic NETLINK Command Definitions
	*/

	static struct genl_ops netlbl_unlabel_genl_c_accept = {
	.cmd = NLBL_UNLABEL_C_ACCEPT,
	.flags = GENL_ADMIN_PERM,
	.policy = netlbl_unlabel_genl_policy,
	.doit = netlbl_unlabel_accept,
	.dumpit = NULL,
	};

	static struct genl_ops netlbl_unlabel_genl_c_list = {
	.cmd = NLBL_UNLABEL_C_LIST,
	.flags = 0,
	.policy = netlbl_unlabel_genl_policy,
	.doit = netlbl_unlabel_list,
	.dumpit = NULL,
	};


	/*
	* NetLabel Generic NETLINK Protocol Functions
	*/

	/**
	* netlbl_unlabel_genl_init - Register the Unlabeled NetLabel component
	*
	* Description:
	* Register the unlabeled packet NetLabel component with the Generic NETLINK
	* mechanism. Returns zero on success, negative values on failure.
	*
	*/
	int netlbl_unlabel_genl_init(void)
	{
	int ret_val;

	ret_val = genl_register_family(&netlbl_unlabel_gnl_family);
	if (ret_val != 0)
	return ret_val;

	ret_val = genl_register_ops(&netlbl_unlabel_gnl_family,
	&netlbl_unlabel_genl_c_accept);
	if (ret_val != 0)
	return ret_val;

	ret_val = genl_register_ops(&netlbl_unlabel_gnl_family,
	&netlbl_unlabel_genl_c_list);
	if (ret_val != 0)
	return ret_val;

	return 0;
	}

	/*
	* NetLabel KAPI Hooks
	*/

	/**
	* netlbl_unlabel_getattr - Get the security attributes for an unlabled packet
	* @secattr: the security attributes
	*
	* Description:
	* Determine the security attributes, if any, for an unlabled packet and return
	* them in @secattr. Returns zero on success and negative values on failure.
	*
	*/
	int netlbl_unlabel_getattr(struct netlbl_lsm_secattr *secattr)
	{
	if (atomic_read(&netlabel_unlabel_accept_flg) == 1)
	return netlbl_secattr_init(secattr);

	return -ENOMSG;
	}

	/**
	* netlbl_unlabel_defconf - Set the default config to allow unlabeled packets
	*
	* Description:
	* Set the default NetLabel configuration to allow incoming unlabeled packets
	* and to send unlabeled network traffic by default.
	*
	*/
	int netlbl_unlabel_defconf(void)
	{
	int ret_val;
	struct netlbl_dom_map *entry;
	u32 secid;

	security_task_getsecid(current, &secid);

	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
	if (entry == NULL)
	return -ENOMEM;
	entry->type = NETLBL_NLTYPE_UNLABELED;
	ret_val = netlbl_domhsh_add_default(entry, secid);
	if (ret_val != 0)
	return ret_val;

	netlbl_unlabel_acceptflg_set(1, secid);

	return 0;
	}