net/netlabel/netlabel_mgmt.c - kernel/msm-4.9 - Gitiles

 /*
  * NetLabel Management Support
  *
  * This file defines the management functions 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/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 <net/cipso_ipv4.h>

 #include "netlabel_domainhash.h"
 #include "netlabel_user.h"
 #include "netlabel_mgmt.h"

 /* NetLabel configured protocol count */
 static DEFINE_SPINLOCK(netlabel_mgmt_protocount_lock);
 static u32 netlabel_mgmt_protocount = 0;

 /* Argument struct for netlbl_domhsh_walk() */
 struct netlbl_domhsh_walk_arg {
 	struct netlink_callback *nl_cb;
 	struct sk_buff *skb;
 	u32 seq;
 };

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

 /* NetLabel Netlink attribute policy */
 static const struct nla_policy netlbl_mgmt_genl_policy[NLBL_MGMT_A_MAX + 1] = {
 	[NLBL_MGMT_A_DOMAIN] = { .type = NLA_NUL_STRING },
 	[NLBL_MGMT_A_PROTOCOL] = { .type = NLA_U32 },
 	[NLBL_MGMT_A_VERSION] = { .type = NLA_U32 },
 	[NLBL_MGMT_A_CV4DOI] = { .type = NLA_U32 },
 };

 /*
  * NetLabel Misc Managment Functions
  */

 /**
  * netlbl_mgmt_protocount_inc - Increment the configured labeled protocol count
  *
  * Description:
  * Increment the number of labeled protocol configurations in the current
  * NetLabel configuration.  Keep track of this for use in determining if
  * NetLabel label enforcement should be active/enabled or not in the LSM.
  *
  */
 void netlbl_mgmt_protocount_inc(void)
 {
 	rcu_read_lock();
 	spin_lock(&netlabel_mgmt_protocount_lock);
 	netlabel_mgmt_protocount++;
 	spin_unlock(&netlabel_mgmt_protocount_lock);
 	rcu_read_unlock();
 }

 /**
  * netlbl_mgmt_protocount_dec - Decrement the configured labeled protocol count
  *
  * Description:
  * Decrement the number of labeled protocol configurations in the current
  * NetLabel configuration.  Keep track of this for use in determining if
  * NetLabel label enforcement should be active/enabled or not in the LSM.
  *
  */
 void netlbl_mgmt_protocount_dec(void)
 {
 	rcu_read_lock();
 	spin_lock(&netlabel_mgmt_protocount_lock);
 	if (netlabel_mgmt_protocount > 0)
 		netlabel_mgmt_protocount--;
 	spin_unlock(&netlabel_mgmt_protocount_lock);
 	rcu_read_unlock();
 }

 /**
  * netlbl_mgmt_protocount_value - Return the number of configured protocols
  *
  * Description:
  * Return the number of labeled protocols in the current NetLabel
  * configuration.  This value is useful in  determining if NetLabel label
  * enforcement should be active/enabled or not in the LSM.
  *
  */
 u32 netlbl_mgmt_protocount_value(void)
 {
 	u32 val;

 	rcu_read_lock();
 	val = netlabel_mgmt_protocount;
 	rcu_read_unlock();

 	return val;
 }

 /*
  * NetLabel Command Handlers
  */

 /**
  * netlbl_mgmt_add - Handle an ADD message
  * @skb: the NETLINK buffer
  * @info: the Generic NETLINK info block
  *
  * Description:
  * Process a user generated ADD message and add the domains from the message
  * to the hash table.  See netlabel.h for a description of the message format.
  * Returns zero on success, negative values on failure.
  *
  */
 static int netlbl_mgmt_add(struct sk_buff *skb, struct genl_info *info)
 {
 	int ret_val = -EINVAL;
 	struct netlbl_dom_map *entry = NULL;
 	size_t tmp_size;
 	u32 tmp_val;
 	struct netlbl_audit audit_info;

 	if (!info->attrs[NLBL_MGMT_A_DOMAIN] ||
 	    !info->attrs[NLBL_MGMT_A_PROTOCOL])
 		goto add_failure;

 	netlbl_netlink_auditinfo(skb, &audit_info);

 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 	if (entry == NULL) {
 		ret_val = -ENOMEM;
 		goto add_failure;
 	}
 	tmp_size = nla_len(info->attrs[NLBL_MGMT_A_DOMAIN]);
 	entry->domain = kmalloc(tmp_size, GFP_KERNEL);
 	if (entry->domain == NULL) {
 		ret_val = -ENOMEM;
 		goto add_failure;
 	}
 	entry->type = nla_get_u32(info->attrs[NLBL_MGMT_A_PROTOCOL]);
 	nla_strlcpy(entry->domain, info->attrs[NLBL_MGMT_A_DOMAIN], tmp_size);

 	switch (entry->type) {
 	case NETLBL_NLTYPE_UNLABELED:
 		ret_val = netlbl_domhsh_add(entry, &audit_info);
 		break;
 	case NETLBL_NLTYPE_CIPSOV4:
 		if (!info->attrs[NLBL_MGMT_A_CV4DOI])
 			goto add_failure;

 		tmp_val = nla_get_u32(info->attrs[NLBL_MGMT_A_CV4DOI]);
 		/* We should be holding a rcu_read_lock() here while we hold
 		 * the result but since the entry will always be deleted when
 		 * the CIPSO DOI is deleted we aren't going to keep the
 		 * lock. */
 		rcu_read_lock();
 		entry->type_def.cipsov4 = cipso_v4_doi_getdef(tmp_val);
 		if (entry->type_def.cipsov4 == NULL) {
 			rcu_read_unlock();
 			goto add_failure;
 		}
 		ret_val = netlbl_domhsh_add(entry, &audit_info);
 		rcu_read_unlock();
 		break;
 	default:
 		goto add_failure;
 	}
 	if (ret_val != 0)
 		goto add_failure;

 	return 0;

 add_failure:
 	if (entry)
 		kfree(entry->domain);
 	kfree(entry);
 	return ret_val;
 }

 /**
  * netlbl_mgmt_remove - Handle a REMOVE message
  * @skb: the NETLINK buffer
  * @info: the Generic NETLINK info block
  *
  * Description:
  * Process a user generated REMOVE message and remove the specified domain
  * mappings.  Returns zero on success, negative values on failure.
  *
  */
 static int netlbl_mgmt_remove(struct sk_buff *skb, struct genl_info *info)
 {
 	char *domain;
 	struct netlbl_audit audit_info;

 	if (!info->attrs[NLBL_MGMT_A_DOMAIN])
 		return -EINVAL;

 	netlbl_netlink_auditinfo(skb, &audit_info);

 	domain = nla_data(info->attrs[NLBL_MGMT_A_DOMAIN]);
 	return netlbl_domhsh_remove(domain, &audit_info);
 }

 /**
  * netlbl_mgmt_listall_cb - netlbl_domhsh_walk() callback for LISTALL
  * @entry: the domain mapping hash table entry
  * @arg: the netlbl_domhsh_walk_arg structure
  *
  * Description:
  * This function is designed to be used as a callback to the
  * netlbl_domhsh_walk() function for use in generating a response for a LISTALL
  * message.  Returns the size of the message on success, negative values on
  * failure.
  *
  */
 static int netlbl_mgmt_listall_cb(struct netlbl_dom_map *entry, void *arg)
 {
 	int ret_val = -ENOMEM;
 	struct netlbl_domhsh_walk_arg *cb_arg = arg;
 	void *data;

 	data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).pid,
 			   cb_arg->seq, &netlbl_mgmt_gnl_family,
 			   NLM_F_MULTI, NLBL_MGMT_C_LISTALL);
 	if (data == NULL)
 		goto listall_cb_failure;

 	ret_val = nla_put_string(cb_arg->skb,
 				 NLBL_MGMT_A_DOMAIN,
 				 entry->domain);
 	if (ret_val != 0)
 		goto listall_cb_failure;
 	ret_val = nla_put_u32(cb_arg->skb, NLBL_MGMT_A_PROTOCOL, entry->type);
 	if (ret_val != 0)
 		goto listall_cb_failure;
 	switch (entry->type) {
 	case NETLBL_NLTYPE_CIPSOV4:
 		ret_val = nla_put_u32(cb_arg->skb,
 				      NLBL_MGMT_A_CV4DOI,
 				      entry->type_def.cipsov4->doi);
 		if (ret_val != 0)
 			goto listall_cb_failure;
 		break;
 	}

 	cb_arg->seq++;
 	return genlmsg_end(cb_arg->skb, data);

 listall_cb_failure:
 	genlmsg_cancel(cb_arg->skb, data);
 	return ret_val;
 }

 /**
  * netlbl_mgmt_listall - Handle a LISTALL message
  * @skb: the NETLINK buffer
  * @cb: the NETLINK callback
  *
  * Description:
  * Process a user generated LISTALL message and dumps the domain hash table in
  * a form suitable for use in a kernel generated LISTALL message.  Returns zero
  * on success, negative values on failure.
  *
  */
 static int netlbl_mgmt_listall(struct sk_buff *skb,
 			       struct netlink_callback *cb)
 {
 	struct netlbl_domhsh_walk_arg cb_arg;
 	u32 skip_bkt = cb->args[0];
 	u32 skip_chain = cb->args[1];

 	cb_arg.nl_cb = cb;
 	cb_arg.skb = skb;
 	cb_arg.seq = cb->nlh->nlmsg_seq;

 	netlbl_domhsh_walk(&skip_bkt,
 			   &skip_chain,
 			   netlbl_mgmt_listall_cb,
 			   &cb_arg);

 	cb->args[0] = skip_bkt;
 	cb->args[1] = skip_chain;
 	return skb->len;
 }

 /**
  * netlbl_mgmt_adddef - Handle an ADDDEF message
  * @skb: the NETLINK buffer
  * @info: the Generic NETLINK info block
  *
  * Description:
  * Process a user generated ADDDEF message and respond accordingly.  Returns
  * zero on success, negative values on failure.
  *
  */
 static int netlbl_mgmt_adddef(struct sk_buff *skb, struct genl_info *info)
 {
 	int ret_val = -EINVAL;
 	struct netlbl_dom_map *entry = NULL;
 	u32 tmp_val;
 	struct netlbl_audit audit_info;

 	if (!info->attrs[NLBL_MGMT_A_PROTOCOL])
 		goto adddef_failure;

 	netlbl_netlink_auditinfo(skb, &audit_info);

 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 	if (entry == NULL) {
 		ret_val = -ENOMEM;
 		goto adddef_failure;
 	}
 	entry->type = nla_get_u32(info->attrs[NLBL_MGMT_A_PROTOCOL]);

 	switch (entry->type) {
 	case NETLBL_NLTYPE_UNLABELED:
 		ret_val = netlbl_domhsh_add_default(entry, &audit_info);
 		break;
 	case NETLBL_NLTYPE_CIPSOV4:
 		if (!info->attrs[NLBL_MGMT_A_CV4DOI])
 			goto adddef_failure;

 		tmp_val = nla_get_u32(info->attrs[NLBL_MGMT_A_CV4DOI]);
 		/* We should be holding a rcu_read_lock() here while we hold
 		 * the result but since the entry will always be deleted when
 		 * the CIPSO DOI is deleted we aren't going to keep the
 		 * lock. */
 		rcu_read_lock();
 		entry->type_def.cipsov4 = cipso_v4_doi_getdef(tmp_val);
 		if (entry->type_def.cipsov4 == NULL) {
 			rcu_read_unlock();
 			goto adddef_failure;
 		}
 		ret_val = netlbl_domhsh_add_default(entry, &audit_info);
 		rcu_read_unlock();
 		break;
 	default:
 		goto adddef_failure;
 	}
 	if (ret_val != 0)
 		goto adddef_failure;

 	return 0;

 adddef_failure:
 	kfree(entry);
 	return ret_val;
 }

 /**
  * netlbl_mgmt_removedef - Handle a REMOVEDEF message
  * @skb: the NETLINK buffer
  * @info: the Generic NETLINK info block
  *
  * Description:
  * Process a user generated REMOVEDEF message and remove the default domain
  * mapping.  Returns zero on success, negative values on failure.
  *
  */
 static int netlbl_mgmt_removedef(struct sk_buff *skb, struct genl_info *info)
 {
 	struct netlbl_audit audit_info;

 	netlbl_netlink_auditinfo(skb, &audit_info);

 	return netlbl_domhsh_remove_default(&audit_info);
 }

 /**
  * netlbl_mgmt_listdef - Handle a LISTDEF message
  * @skb: the NETLINK buffer
  * @info: the Generic NETLINK info block
  *
  * Description:
  * Process a user generated LISTDEF message and dumps the default domain
  * mapping in a form suitable for use in a kernel generated LISTDEF message.
  * Returns zero on success, negative values on failure.
  *
  */
 static int netlbl_mgmt_listdef(struct sk_buff *skb, struct genl_info *info)
 {
 	int ret_val = -ENOMEM;
 	struct sk_buff *ans_skb = NULL;
 	void *data;
 	struct netlbl_dom_map *entry;

 	ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 	if (ans_skb == NULL)
 		return -ENOMEM;
 	data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family,
 				 0, NLBL_MGMT_C_LISTDEF);
 	if (data == NULL)
 		goto listdef_failure;

 	rcu_read_lock();
 	entry = netlbl_domhsh_getentry(NULL);
 	if (entry == NULL) {
 		ret_val = -ENOENT;
 		goto listdef_failure_lock;
 	}
 	ret_val = nla_put_u32(ans_skb, NLBL_MGMT_A_PROTOCOL, entry->type);
 	if (ret_val != 0)
 		goto listdef_failure_lock;
 	switch (entry->type) {
 	case NETLBL_NLTYPE_CIPSOV4:
 		ret_val = nla_put_u32(ans_skb,
 				      NLBL_MGMT_A_CV4DOI,
 				      entry->type_def.cipsov4->doi);
 		if (ret_val != 0)
 			goto listdef_failure_lock;
 		break;
 	}
 	rcu_read_unlock();

 	genlmsg_end(ans_skb, data);

 	ret_val = genlmsg_reply(ans_skb, info);
 	if (ret_val != 0)
 		goto listdef_failure;
 	return 0;

 listdef_failure_lock:
 	rcu_read_unlock();
 listdef_failure:
 	kfree_skb(ans_skb);
 	return ret_val;
 }

 /**
  * netlbl_mgmt_protocols_cb - Write an individual PROTOCOL message response
  * @skb: the skb to write to
  * @seq: the NETLINK sequence number
  * @cb: the NETLINK callback
  * @protocol: the NetLabel protocol to use in the message
  *
  * Description:
  * This function is to be used in conjunction with netlbl_mgmt_protocols() to
  * answer a application's PROTOCOLS message.  Returns the size of the message
  * on success, negative values on failure.
  *
  */
 static int netlbl_mgmt_protocols_cb(struct sk_buff *skb,
 				    struct netlink_callback *cb,
 				    u32 protocol)
 {
 	int ret_val = -ENOMEM;
 	void *data;

 	data = genlmsg_put(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
 			   &netlbl_mgmt_gnl_family, NLM_F_MULTI,
 			   NLBL_MGMT_C_PROTOCOLS);
 	if (data == NULL)
 		goto protocols_cb_failure;

 	ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL, protocol);
 	if (ret_val != 0)
 		goto protocols_cb_failure;

 	return genlmsg_end(skb, data);

 protocols_cb_failure:
 	genlmsg_cancel(skb, data);
 	return ret_val;
 }

 /**
  * netlbl_mgmt_protocols - Handle a PROTOCOLS message
  * @skb: the NETLINK buffer
  * @cb: the NETLINK callback
  *
  * Description:
  * Process a user generated PROTOCOLS message and respond accordingly.
  *
  */
 static int netlbl_mgmt_protocols(struct sk_buff *skb,
 				 struct netlink_callback *cb)
 {
 	u32 protos_sent = cb->args[0];

 	if (protos_sent == 0) {
 		if (netlbl_mgmt_protocols_cb(skb,
 					     cb,
 					     NETLBL_NLTYPE_UNLABELED) < 0)
 			goto protocols_return;
 		protos_sent++;
 	}
 	if (protos_sent == 1) {
 		if (netlbl_mgmt_protocols_cb(skb,
 					     cb,
 					     NETLBL_NLTYPE_CIPSOV4) < 0)
 			goto protocols_return;
 		protos_sent++;
 	}

 protocols_return:
 	cb->args[0] = protos_sent;
 	return skb->len;
 }

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

 	ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 	if (ans_skb == NULL)
 		return -ENOMEM;
 	data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family,
 				 0, NLBL_MGMT_C_VERSION);
 	if (data == NULL)
 		goto version_failure;

 	ret_val = nla_put_u32(ans_skb,
 			      NLBL_MGMT_A_VERSION,
 			      NETLBL_PROTO_VERSION);
 	if (ret_val != 0)
 		goto version_failure;

 	genlmsg_end(ans_skb, data);

 	ret_val = genlmsg_reply(ans_skb, info);
 	if (ret_val != 0)
 		goto version_failure;
 	return 0;

 version_failure:
 	kfree_skb(ans_skb);
 	return ret_val;
 }


 /*
  * NetLabel Generic NETLINK Command Definitions
  */

 static struct genl_ops netlbl_mgmt_genl_c_add = {
 	.cmd = NLBL_MGMT_C_ADD,
 	.flags = GENL_ADMIN_PERM,
 	.policy = netlbl_mgmt_genl_policy,
 	.doit = netlbl_mgmt_add,
 	.dumpit = NULL,
 };

 static struct genl_ops netlbl_mgmt_genl_c_remove = {
 	.cmd = NLBL_MGMT_C_REMOVE,
 	.flags = GENL_ADMIN_PERM,
 	.policy = netlbl_mgmt_genl_policy,
 	.doit = netlbl_mgmt_remove,
 	.dumpit = NULL,
 };

 static struct genl_ops netlbl_mgmt_genl_c_listall = {
 	.cmd = NLBL_MGMT_C_LISTALL,
 	.flags = 0,
 	.policy = netlbl_mgmt_genl_policy,
 	.doit = NULL,
 	.dumpit = netlbl_mgmt_listall,
 };

 static struct genl_ops netlbl_mgmt_genl_c_adddef = {
 	.cmd = NLBL_MGMT_C_ADDDEF,
 	.flags = GENL_ADMIN_PERM,
 	.policy = netlbl_mgmt_genl_policy,
 	.doit = netlbl_mgmt_adddef,
 	.dumpit = NULL,
 };

 static struct genl_ops netlbl_mgmt_genl_c_removedef = {
 	.cmd = NLBL_MGMT_C_REMOVEDEF,
 	.flags = GENL_ADMIN_PERM,
 	.policy = netlbl_mgmt_genl_policy,
 	.doit = netlbl_mgmt_removedef,
 	.dumpit = NULL,
 };

 static struct genl_ops netlbl_mgmt_genl_c_listdef = {
 	.cmd = NLBL_MGMT_C_LISTDEF,
 	.flags = 0,
 	.policy = netlbl_mgmt_genl_policy,
 	.doit = netlbl_mgmt_listdef,
 	.dumpit = NULL,
 };

 static struct genl_ops netlbl_mgmt_genl_c_protocols = {
 	.cmd = NLBL_MGMT_C_PROTOCOLS,
 	.flags = 0,
 	.policy = netlbl_mgmt_genl_policy,
 	.doit = NULL,
 	.dumpit = netlbl_mgmt_protocols,
 };

 static struct genl_ops netlbl_mgmt_genl_c_version = {
 	.cmd = NLBL_MGMT_C_VERSION,
 	.flags = 0,
 	.policy = netlbl_mgmt_genl_policy,
 	.doit = netlbl_mgmt_version,
 	.dumpit = NULL,
 };

 /*
  * NetLabel Generic NETLINK Protocol Functions
  */

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

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

 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
 				    &netlbl_mgmt_genl_c_add);
 	if (ret_val != 0)
 		return ret_val;
 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
 				    &netlbl_mgmt_genl_c_remove);
 	if (ret_val != 0)
 		return ret_val;
 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
 				    &netlbl_mgmt_genl_c_listall);
 	if (ret_val != 0)
 		return ret_val;
 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
 				    &netlbl_mgmt_genl_c_adddef);
 	if (ret_val != 0)
 		return ret_val;
 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
 				    &netlbl_mgmt_genl_c_removedef);
 	if (ret_val != 0)
 		return ret_val;
 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
 				    &netlbl_mgmt_genl_c_listdef);
 	if (ret_val != 0)
 		return ret_val;
 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
 				    &netlbl_mgmt_genl_c_protocols);
 	if (ret_val != 0)
 		return ret_val;
 	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
 				    &netlbl_mgmt_genl_c_version);
 	if (ret_val != 0)
 		return ret_val;

 	return 0;
 }
	/*
	* NetLabel Management Support
	*
	* This file defines the management functions 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/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 <net/cipso_ipv4.h>

	#include "netlabel_domainhash.h"
	#include "netlabel_user.h"
	#include "netlabel_mgmt.h"

	/* NetLabel configured protocol count */
	static DEFINE_SPINLOCK(netlabel_mgmt_protocount_lock);
	static u32 netlabel_mgmt_protocount = 0;

	/* Argument struct for netlbl_domhsh_walk() */
	struct netlbl_domhsh_walk_arg {
	struct netlink_callback *nl_cb;
	struct sk_buff *skb;
	u32 seq;
	};

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

	/* NetLabel Netlink attribute policy */
	static const struct nla_policy netlbl_mgmt_genl_policy[NLBL_MGMT_A_MAX + 1] = {
	[NLBL_MGMT_A_DOMAIN] = { .type = NLA_NUL_STRING },
	[NLBL_MGMT_A_PROTOCOL] = { .type = NLA_U32 },
	[NLBL_MGMT_A_VERSION] = { .type = NLA_U32 },
	[NLBL_MGMT_A_CV4DOI] = { .type = NLA_U32 },
	};

	/*
	* NetLabel Misc Managment Functions
	*/

	/**
	* netlbl_mgmt_protocount_inc - Increment the configured labeled protocol count
	*
	* Description:
	* Increment the number of labeled protocol configurations in the current
	* NetLabel configuration. Keep track of this for use in determining if
	* NetLabel label enforcement should be active/enabled or not in the LSM.
	*
	*/
	void netlbl_mgmt_protocount_inc(void)
	{
	rcu_read_lock();
	spin_lock(&netlabel_mgmt_protocount_lock);
	netlabel_mgmt_protocount++;
	spin_unlock(&netlabel_mgmt_protocount_lock);
	rcu_read_unlock();
	}

	/**
	* netlbl_mgmt_protocount_dec - Decrement the configured labeled protocol count
	*
	* Description:
	* Decrement the number of labeled protocol configurations in the current
	* NetLabel configuration. Keep track of this for use in determining if
	* NetLabel label enforcement should be active/enabled or not in the LSM.
	*
	*/
	void netlbl_mgmt_protocount_dec(void)
	{
	rcu_read_lock();
	spin_lock(&netlabel_mgmt_protocount_lock);
	if (netlabel_mgmt_protocount > 0)
	netlabel_mgmt_protocount--;
	spin_unlock(&netlabel_mgmt_protocount_lock);
	rcu_read_unlock();
	}

	/**
	* netlbl_mgmt_protocount_value - Return the number of configured protocols
	*
	* Description:
	* Return the number of labeled protocols in the current NetLabel
	* configuration. This value is useful in determining if NetLabel label
	* enforcement should be active/enabled or not in the LSM.
	*
	*/
	u32 netlbl_mgmt_protocount_value(void)
	{
	u32 val;

	rcu_read_lock();
	val = netlabel_mgmt_protocount;
	rcu_read_unlock();

	return val;
	}

	/*
	* NetLabel Command Handlers
	*/

	/**
	* netlbl_mgmt_add - Handle an ADD message
	* @skb: the NETLINK buffer
	* @info: the Generic NETLINK info block
	*
	* Description:
	* Process a user generated ADD message and add the domains from the message
	* to the hash table. See netlabel.h for a description of the message format.
	* Returns zero on success, negative values on failure.
	*
	*/
	static int netlbl_mgmt_add(struct sk_buff skb, struct genl_info info)
	{
	int ret_val = -EINVAL;
	struct netlbl_dom_map *entry = NULL;
	size_t tmp_size;
	u32 tmp_val;
	struct netlbl_audit audit_info;

	if (!info->attrs[NLBL_MGMT_A_DOMAIN] \|\|
	!info->attrs[NLBL_MGMT_A_PROTOCOL])
	goto add_failure;

	netlbl_netlink_auditinfo(skb, &audit_info);

	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
	if (entry == NULL) {
	ret_val = -ENOMEM;
	goto add_failure;
	}
	tmp_size = nla_len(info->attrs[NLBL_MGMT_A_DOMAIN]);
	entry->domain = kmalloc(tmp_size, GFP_KERNEL);
	if (entry->domain == NULL) {
	ret_val = -ENOMEM;
	goto add_failure;
	}
	entry->type = nla_get_u32(info->attrs[NLBL_MGMT_A_PROTOCOL]);
	nla_strlcpy(entry->domain, info->attrs[NLBL_MGMT_A_DOMAIN], tmp_size);

	switch (entry->type) {
	case NETLBL_NLTYPE_UNLABELED:
	ret_val = netlbl_domhsh_add(entry, &audit_info);
	break;
	case NETLBL_NLTYPE_CIPSOV4:
	if (!info->attrs[NLBL_MGMT_A_CV4DOI])
	goto add_failure;

	tmp_val = nla_get_u32(info->attrs[NLBL_MGMT_A_CV4DOI]);
	/* We should be holding a rcu_read_lock() here while we hold
	* the result but since the entry will always be deleted when
	* the CIPSO DOI is deleted we aren't going to keep the
	* lock. */
	rcu_read_lock();
	entry->type_def.cipsov4 = cipso_v4_doi_getdef(tmp_val);
	if (entry->type_def.cipsov4 == NULL) {
	rcu_read_unlock();
	goto add_failure;
	}
	ret_val = netlbl_domhsh_add(entry, &audit_info);
	rcu_read_unlock();
	break;
	default:
	goto add_failure;
	}
	if (ret_val != 0)
	goto add_failure;

	return 0;

	add_failure:
	if (entry)
	kfree(entry->domain);
	kfree(entry);
	return ret_val;
	}

	/**
	* netlbl_mgmt_remove - Handle a REMOVE message
	* @skb: the NETLINK buffer
	* @info: the Generic NETLINK info block
	*
	* Description:
	* Process a user generated REMOVE message and remove the specified domain
	* mappings. Returns zero on success, negative values on failure.
	*
	*/
	static int netlbl_mgmt_remove(struct sk_buff skb, struct genl_info info)
	{
	char *domain;
	struct netlbl_audit audit_info;

	if (!info->attrs[NLBL_MGMT_A_DOMAIN])
	return -EINVAL;

	netlbl_netlink_auditinfo(skb, &audit_info);

	domain = nla_data(info->attrs[NLBL_MGMT_A_DOMAIN]);
	return netlbl_domhsh_remove(domain, &audit_info);
	}

	/**
	* netlbl_mgmt_listall_cb - netlbl_domhsh_walk() callback for LISTALL
	* @entry: the domain mapping hash table entry
	* @arg: the netlbl_domhsh_walk_arg structure
	*
	* Description:
	* This function is designed to be used as a callback to the
	* netlbl_domhsh_walk() function for use in generating a response for a LISTALL
	* message. Returns the size of the message on success, negative values on
	* failure.
	*
	*/
	static int netlbl_mgmt_listall_cb(struct netlbl_dom_map entry, void arg)
	{
	int ret_val = -ENOMEM;
	struct netlbl_domhsh_walk_arg *cb_arg = arg;
	void *data;

	data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).pid,
	cb_arg->seq, &netlbl_mgmt_gnl_family,
	NLM_F_MULTI, NLBL_MGMT_C_LISTALL);
	if (data == NULL)
	goto listall_cb_failure;

	ret_val = nla_put_string(cb_arg->skb,
	NLBL_MGMT_A_DOMAIN,
	entry->domain);
	if (ret_val != 0)
	goto listall_cb_failure;
	ret_val = nla_put_u32(cb_arg->skb, NLBL_MGMT_A_PROTOCOL, entry->type);
	if (ret_val != 0)
	goto listall_cb_failure;
	switch (entry->type) {
	case NETLBL_NLTYPE_CIPSOV4:
	ret_val = nla_put_u32(cb_arg->skb,
	NLBL_MGMT_A_CV4DOI,
	entry->type_def.cipsov4->doi);
	if (ret_val != 0)
	goto listall_cb_failure;
	break;
	}

	cb_arg->seq++;
	return genlmsg_end(cb_arg->skb, data);

	listall_cb_failure:
	genlmsg_cancel(cb_arg->skb, data);
	return ret_val;
	}

	/**
	* netlbl_mgmt_listall - Handle a LISTALL message
	* @skb: the NETLINK buffer
	* @cb: the NETLINK callback
	*
	* Description:
	* Process a user generated LISTALL message and dumps the domain hash table in
	* a form suitable for use in a kernel generated LISTALL message. Returns zero
	* on success, negative values on failure.
	*
	*/
	static int netlbl_mgmt_listall(struct sk_buff *skb,
	struct netlink_callback *cb)
	{
	struct netlbl_domhsh_walk_arg cb_arg;
	u32 skip_bkt = cb->args[0];
	u32 skip_chain = cb->args[1];

	cb_arg.nl_cb = cb;
	cb_arg.skb = skb;
	cb_arg.seq = cb->nlh->nlmsg_seq;

	netlbl_domhsh_walk(&skip_bkt,
	&skip_chain,
	netlbl_mgmt_listall_cb,
	&cb_arg);

	cb->args[0] = skip_bkt;
	cb->args[1] = skip_chain;
	return skb->len;
	}

	/**
	* netlbl_mgmt_adddef - Handle an ADDDEF message
	* @skb: the NETLINK buffer
	* @info: the Generic NETLINK info block
	*
	* Description:
	* Process a user generated ADDDEF message and respond accordingly. Returns
	* zero on success, negative values on failure.
	*
	*/
	static int netlbl_mgmt_adddef(struct sk_buff skb, struct genl_info info)
	{
	int ret_val = -EINVAL;
	struct netlbl_dom_map *entry = NULL;
	u32 tmp_val;
	struct netlbl_audit audit_info;

	if (!info->attrs[NLBL_MGMT_A_PROTOCOL])
	goto adddef_failure;

	netlbl_netlink_auditinfo(skb, &audit_info);

	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
	if (entry == NULL) {
	ret_val = -ENOMEM;
	goto adddef_failure;
	}
	entry->type = nla_get_u32(info->attrs[NLBL_MGMT_A_PROTOCOL]);

	switch (entry->type) {
	case NETLBL_NLTYPE_UNLABELED:
	ret_val = netlbl_domhsh_add_default(entry, &audit_info);
	break;
	case NETLBL_NLTYPE_CIPSOV4:
	if (!info->attrs[NLBL_MGMT_A_CV4DOI])
	goto adddef_failure;

	tmp_val = nla_get_u32(info->attrs[NLBL_MGMT_A_CV4DOI]);
	/* We should be holding a rcu_read_lock() here while we hold
	* the result but since the entry will always be deleted when
	* the CIPSO DOI is deleted we aren't going to keep the
	* lock. */
	rcu_read_lock();
	entry->type_def.cipsov4 = cipso_v4_doi_getdef(tmp_val);
	if (entry->type_def.cipsov4 == NULL) {
	rcu_read_unlock();
	goto adddef_failure;
	}
	ret_val = netlbl_domhsh_add_default(entry, &audit_info);
	rcu_read_unlock();
	break;
	default:
	goto adddef_failure;
	}
	if (ret_val != 0)
	goto adddef_failure;

	return 0;

	adddef_failure:
	kfree(entry);
	return ret_val;
	}

	/**
	* netlbl_mgmt_removedef - Handle a REMOVEDEF message
	* @skb: the NETLINK buffer
	* @info: the Generic NETLINK info block
	*
	* Description:
	* Process a user generated REMOVEDEF message and remove the default domain
	* mapping. Returns zero on success, negative values on failure.
	*
	*/
	static int netlbl_mgmt_removedef(struct sk_buff skb, struct genl_info info)
	{
	struct netlbl_audit audit_info;

	netlbl_netlink_auditinfo(skb, &audit_info);

	return netlbl_domhsh_remove_default(&audit_info);
	}

	/**
	* netlbl_mgmt_listdef - Handle a LISTDEF message
	* @skb: the NETLINK buffer
	* @info: the Generic NETLINK info block
	*
	* Description:
	* Process a user generated LISTDEF message and dumps the default domain
	* mapping in a form suitable for use in a kernel generated LISTDEF message.
	* Returns zero on success, negative values on failure.
	*
	*/
	static int netlbl_mgmt_listdef(struct sk_buff skb, struct genl_info info)
	{
	int ret_val = -ENOMEM;
	struct sk_buff *ans_skb = NULL;
	void *data;
	struct netlbl_dom_map *entry;

	ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
	if (ans_skb == NULL)
	return -ENOMEM;
	data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family,
	0, NLBL_MGMT_C_LISTDEF);
	if (data == NULL)
	goto listdef_failure;

	rcu_read_lock();
	entry = netlbl_domhsh_getentry(NULL);
	if (entry == NULL) {
	ret_val = -ENOENT;
	goto listdef_failure_lock;
	}
	ret_val = nla_put_u32(ans_skb, NLBL_MGMT_A_PROTOCOL, entry->type);
	if (ret_val != 0)
	goto listdef_failure_lock;
	switch (entry->type) {
	case NETLBL_NLTYPE_CIPSOV4:
	ret_val = nla_put_u32(ans_skb,
	NLBL_MGMT_A_CV4DOI,
	entry->type_def.cipsov4->doi);
	if (ret_val != 0)
	goto listdef_failure_lock;
	break;
	}
	rcu_read_unlock();

	genlmsg_end(ans_skb, data);

	ret_val = genlmsg_reply(ans_skb, info);
	if (ret_val != 0)
	goto listdef_failure;
	return 0;

	listdef_failure_lock:
	rcu_read_unlock();
	listdef_failure:
	kfree_skb(ans_skb);
	return ret_val;
	}

	/**
	* netlbl_mgmt_protocols_cb - Write an individual PROTOCOL message response
	* @skb: the skb to write to
	* @seq: the NETLINK sequence number
	* @cb: the NETLINK callback
	* @protocol: the NetLabel protocol to use in the message
	*
	* Description:
	* This function is to be used in conjunction with netlbl_mgmt_protocols() to
	* answer a application's PROTOCOLS message. Returns the size of the message
	* on success, negative values on failure.
	*
	*/
	static int netlbl_mgmt_protocols_cb(struct sk_buff *skb,
	struct netlink_callback *cb,
	u32 protocol)
	{
	int ret_val = -ENOMEM;
	void *data;

	data = genlmsg_put(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
	&netlbl_mgmt_gnl_family, NLM_F_MULTI,
	NLBL_MGMT_C_PROTOCOLS);
	if (data == NULL)
	goto protocols_cb_failure;

	ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL, protocol);
	if (ret_val != 0)
	goto protocols_cb_failure;

	return genlmsg_end(skb, data);

	protocols_cb_failure:
	genlmsg_cancel(skb, data);
	return ret_val;
	}

	/**
	* netlbl_mgmt_protocols - Handle a PROTOCOLS message
	* @skb: the NETLINK buffer
	* @cb: the NETLINK callback
	*
	* Description:
	* Process a user generated PROTOCOLS message and respond accordingly.
	*
	*/
	static int netlbl_mgmt_protocols(struct sk_buff *skb,
	struct netlink_callback *cb)
	{
	u32 protos_sent = cb->args[0];

	if (protos_sent == 0) {
	if (netlbl_mgmt_protocols_cb(skb,
	cb,
	NETLBL_NLTYPE_UNLABELED) < 0)
	goto protocols_return;
	protos_sent++;
	}
	if (protos_sent == 1) {
	if (netlbl_mgmt_protocols_cb(skb,
	cb,
	NETLBL_NLTYPE_CIPSOV4) < 0)
	goto protocols_return;
	protos_sent++;
	}

	protocols_return:
	cb->args[0] = protos_sent;
	return skb->len;
	}

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

	ans_skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
	if (ans_skb == NULL)
	return -ENOMEM;
	data = genlmsg_put_reply(ans_skb, info, &netlbl_mgmt_gnl_family,
	0, NLBL_MGMT_C_VERSION);
	if (data == NULL)
	goto version_failure;

	ret_val = nla_put_u32(ans_skb,
	NLBL_MGMT_A_VERSION,
	NETLBL_PROTO_VERSION);
	if (ret_val != 0)
	goto version_failure;

	genlmsg_end(ans_skb, data);

	ret_val = genlmsg_reply(ans_skb, info);
	if (ret_val != 0)
	goto version_failure;
	return 0;

	version_failure:
	kfree_skb(ans_skb);
	return ret_val;
	}


	/*
	* NetLabel Generic NETLINK Command Definitions
	*/

	static struct genl_ops netlbl_mgmt_genl_c_add = {
	.cmd = NLBL_MGMT_C_ADD,
	.flags = GENL_ADMIN_PERM,
	.policy = netlbl_mgmt_genl_policy,
	.doit = netlbl_mgmt_add,
	.dumpit = NULL,
	};

	static struct genl_ops netlbl_mgmt_genl_c_remove = {
	.cmd = NLBL_MGMT_C_REMOVE,
	.flags = GENL_ADMIN_PERM,
	.policy = netlbl_mgmt_genl_policy,
	.doit = netlbl_mgmt_remove,
	.dumpit = NULL,
	};

	static struct genl_ops netlbl_mgmt_genl_c_listall = {
	.cmd = NLBL_MGMT_C_LISTALL,
	.flags = 0,
	.policy = netlbl_mgmt_genl_policy,
	.doit = NULL,
	.dumpit = netlbl_mgmt_listall,
	};

	static struct genl_ops netlbl_mgmt_genl_c_adddef = {
	.cmd = NLBL_MGMT_C_ADDDEF,
	.flags = GENL_ADMIN_PERM,
	.policy = netlbl_mgmt_genl_policy,
	.doit = netlbl_mgmt_adddef,
	.dumpit = NULL,
	};

	static struct genl_ops netlbl_mgmt_genl_c_removedef = {
	.cmd = NLBL_MGMT_C_REMOVEDEF,
	.flags = GENL_ADMIN_PERM,
	.policy = netlbl_mgmt_genl_policy,
	.doit = netlbl_mgmt_removedef,
	.dumpit = NULL,
	};

	static struct genl_ops netlbl_mgmt_genl_c_listdef = {
	.cmd = NLBL_MGMT_C_LISTDEF,
	.flags = 0,
	.policy = netlbl_mgmt_genl_policy,
	.doit = netlbl_mgmt_listdef,
	.dumpit = NULL,
	};

	static struct genl_ops netlbl_mgmt_genl_c_protocols = {
	.cmd = NLBL_MGMT_C_PROTOCOLS,
	.flags = 0,
	.policy = netlbl_mgmt_genl_policy,
	.doit = NULL,
	.dumpit = netlbl_mgmt_protocols,
	};

	static struct genl_ops netlbl_mgmt_genl_c_version = {
	.cmd = NLBL_MGMT_C_VERSION,
	.flags = 0,
	.policy = netlbl_mgmt_genl_policy,
	.doit = netlbl_mgmt_version,
	.dumpit = NULL,
	};

	/*
	* NetLabel Generic NETLINK Protocol Functions
	*/

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

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

	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
	&netlbl_mgmt_genl_c_add);
	if (ret_val != 0)
	return ret_val;
	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
	&netlbl_mgmt_genl_c_remove);
	if (ret_val != 0)
	return ret_val;
	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
	&netlbl_mgmt_genl_c_listall);
	if (ret_val != 0)
	return ret_val;
	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
	&netlbl_mgmt_genl_c_adddef);
	if (ret_val != 0)
	return ret_val;
	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
	&netlbl_mgmt_genl_c_removedef);
	if (ret_val != 0)
	return ret_val;
	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
	&netlbl_mgmt_genl_c_listdef);
	if (ret_val != 0)
	return ret_val;
	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
	&netlbl_mgmt_genl_c_protocols);
	if (ret_val != 0)
	return ret_val;
	ret_val = genl_register_ops(&netlbl_mgmt_gnl_family,
	&netlbl_mgmt_genl_c_version);
	if (ret_val != 0)
	return ret_val;

	return 0;
	}