[mirror_ubuntu-artful-kernel.git] / net / netlabel / netlabel_domainhash.c

/*
 * NetLabel Domain Hash Table
 *
 * This file manages the domain hash table that NetLabel uses to determine
 * which network labeling protocol to use for a given domain.  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/rculist.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/audit.h>
#include <net/netlabel.h>
#include <net/cipso_ipv4.h>
#include <asm/bug.h>

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

struct netlbl_domhsh_tbl {
	struct list_head *tbl;
	u32 size;
};

/* Domain hash table */
/* XXX - updates should be so rare that having one spinlock for the entire
 * hash table should be okay */
static DEFINE_SPINLOCK(netlbl_domhsh_lock);
static struct netlbl_domhsh_tbl *netlbl_domhsh = NULL;
static struct netlbl_dom_map *netlbl_domhsh_def = NULL;

/*
 * Domain Hash Table Helper Functions
 */

/**
 * netlbl_domhsh_free_entry - Frees a domain hash table entry
 * @entry: the entry's RCU field
 *
 * Description:
 * This function is designed to be used as a callback to the call_rcu()
 * function so that the memory allocated to a hash table entry can be released
 * safely.
 *
 */
static void netlbl_domhsh_free_entry(struct rcu_head *entry)
{
	struct netlbl_dom_map *ptr;

	ptr = container_of(entry, struct netlbl_dom_map, rcu);
	kfree(ptr->domain);
	kfree(ptr);
}

/**
 * netlbl_domhsh_hash - Hashing function for the domain hash table
 * @domain: the domain name to hash
 *
 * Description:
 * This is the hashing function for the domain hash table, it returns the
 * correct bucket number for the domain.  The caller is responsibile for
 * calling the rcu_read_[un]lock() functions.
 *
 */
static u32 netlbl_domhsh_hash(const char *key)
{
	u32 iter;
	u32 val;
	u32 len;

	/* This is taken (with slight modification) from
	 * security/selinux/ss/symtab.c:symhash() */

	for (iter = 0, val = 0, len = strlen(key); iter < len; iter++)
		val = (val << 4 | (val >> (8 * sizeof(u32) - 4))) ^ key[iter];
	return val & (rcu_dereference(netlbl_domhsh)->size - 1);
}

/**
 * netlbl_domhsh_search - Search for a domain entry
 * @domain: the domain
 *
 * Description:
 * Searches the domain hash table and returns a pointer to the hash table
 * entry if found, otherwise NULL is returned.  The caller is responsibile for
 * the rcu hash table locks (i.e. the caller much call rcu_read_[un]lock()).
 *
 */
static struct netlbl_dom_map *netlbl_domhsh_search(const char *domain)
{
	u32 bkt;
	struct list_head *bkt_list;
	struct netlbl_dom_map *iter;

	if (domain != NULL) {
		bkt = netlbl_domhsh_hash(domain);
		bkt_list = &rcu_dereference(netlbl_domhsh)->tbl[bkt];
		list_for_each_entry_rcu(iter, bkt_list, list)
			if (iter->valid && strcmp(iter->domain, domain) == 0)
				return iter;
	}

	return NULL;
}

/**
 * netlbl_domhsh_search_def - Search for a domain entry
 * @domain: the domain
 * @def: return default if no match is found
 *
 * Description:
 * Searches the domain hash table and returns a pointer to the hash table
 * entry if an exact match is found, if an exact match is not present in the
 * hash table then the default entry is returned if valid otherwise NULL is
 * returned.  The caller is responsibile for the rcu hash table locks
 * (i.e. the caller much call rcu_read_[un]lock()).
 *
 */
static struct netlbl_dom_map *netlbl_domhsh_search_def(const char *domain)
{
	struct netlbl_dom_map *entry;

	entry = netlbl_domhsh_search(domain);
	if (entry == NULL) {
		entry = rcu_dereference(netlbl_domhsh_def);
		if (entry != NULL && !entry->valid)
			entry = NULL;
	}

	return entry;
}

/*
 * Domain Hash Table Functions
 */

/**
 * netlbl_domhsh_init - Init for the domain hash
 * @size: the number of bits to use for the hash buckets
 *
 * Description:
 * Initializes the domain hash table, should be called only by
 * netlbl_user_init() during initialization.  Returns zero on success, non-zero
 * values on error.
 *
 */
int __init netlbl_domhsh_init(u32 size)
{
	u32 iter;
	struct netlbl_domhsh_tbl *hsh_tbl;

	if (size == 0)
		return -EINVAL;

	hsh_tbl = kmalloc(sizeof(*hsh_tbl), GFP_KERNEL);
	if (hsh_tbl == NULL)
		return -ENOMEM;
	hsh_tbl->size = 1 << size;
	hsh_tbl->tbl = kcalloc(hsh_tbl->size,
			       sizeof(struct list_head),
			       GFP_KERNEL);
	if (hsh_tbl->tbl == NULL) {
		kfree(hsh_tbl);
		return -ENOMEM;
	}
	for (iter = 0; iter < hsh_tbl->size; iter++)
		INIT_LIST_HEAD(&hsh_tbl->tbl[iter]);

	spin_lock(&netlbl_domhsh_lock);
	rcu_assign_pointer(netlbl_domhsh, hsh_tbl);
	spin_unlock(&netlbl_domhsh_lock);

	return 0;
}

/**
 * netlbl_domhsh_add - Adds a entry to the domain hash table
 * @entry: the entry to add
 * @audit_info: NetLabel audit information
 *
 * Description:
 * Adds a new entry to the domain hash table and handles any updates to the
 * lower level protocol handler (i.e. CIPSO).  Returns zero on success,
 * negative on failure.
 *
 */
int netlbl_domhsh_add(struct netlbl_dom_map *entry,
		      struct netlbl_audit *audit_info)
{
	int ret_val;
	u32 bkt;
	struct audit_buffer *audit_buf;

	entry->valid = 1;
	INIT_RCU_HEAD(&entry->rcu);

	rcu_read_lock();
	spin_lock(&netlbl_domhsh_lock);
	if (entry->domain != NULL) {
		bkt = netlbl_domhsh_hash(entry->domain);
		if (netlbl_domhsh_search(entry->domain) == NULL)
			list_add_tail_rcu(&entry->list,
				    &rcu_dereference(netlbl_domhsh)->tbl[bkt]);
		else
			ret_val = -EEXIST;
	} else {
		INIT_LIST_HEAD(&entry->list);
		if (rcu_dereference(netlbl_domhsh_def) == NULL)
			rcu_assign_pointer(netlbl_domhsh_def, entry);
		else
			ret_val = -EEXIST;
	}
	spin_unlock(&netlbl_domhsh_lock);
	audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_ADD, audit_info);
	if (audit_buf != NULL) {
		audit_log_format(audit_buf,
				 " nlbl_domain=%s",
				 entry->domain ? entry->domain : "(default)");
		switch (entry->type) {
		case NETLBL_NLTYPE_UNLABELED:
			audit_log_format(audit_buf, " nlbl_protocol=unlbl");
			break;
		case NETLBL_NLTYPE_CIPSOV4:
			audit_log_format(audit_buf,
					 " nlbl_protocol=cipsov4 cipso_doi=%u",
					 entry->type_def.cipsov4->doi);
			break;
		}
		audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
		audit_log_end(audit_buf);
	}
	rcu_read_unlock();

	return ret_val;
}

/**
 * netlbl_domhsh_add_default - Adds the default entry to the domain hash table
 * @entry: the entry to add
 * @audit_info: NetLabel audit information
 *
 * Description:
 * Adds a new default entry to the domain hash table and handles any updates
 * to the lower level protocol handler (i.e. CIPSO).  Returns zero on success,
 * negative on failure.
 *
 */
int netlbl_domhsh_add_default(struct netlbl_dom_map *entry,
			      struct netlbl_audit *audit_info)
{
	return netlbl_domhsh_add(entry, audit_info);
}

/**
 * netlbl_domhsh_remove_entry - Removes a given entry from the domain table
 * @entry: the entry to remove
 * @audit_info: NetLabel audit information
 *
 * Description:
 * Removes an entry from the domain hash table and handles any updates to the
 * lower level protocol handler (i.e. CIPSO).  Caller is responsible for
 * ensuring that the RCU read lock is held.  Returns zero on success, negative
 * on failure.
 *
 */
int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry,
			       struct netlbl_audit *audit_info)
{
	int ret_val = 0;
	struct audit_buffer *audit_buf;

	if (entry == NULL)
		return -ENOENT;

	spin_lock(&netlbl_domhsh_lock);
	if (entry->valid) {
		entry->valid = 0;
		if (entry != rcu_dereference(netlbl_domhsh_def))
			list_del_rcu(&entry->list);
		else
			rcu_assign_pointer(netlbl_domhsh_def, NULL);
	} else
		ret_val = -ENOENT;
	spin_unlock(&netlbl_domhsh_lock);

	audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL, audit_info);
	if (audit_buf != NULL) {
		audit_log_format(audit_buf,
				 " nlbl_domain=%s res=%u",
				 entry->domain ? entry->domain : "(default)",
				 ret_val == 0 ? 1 : 0);
		audit_log_end(audit_buf);
	}

	if (ret_val == 0) {
		switch (entry->type) {
		case NETLBL_NLTYPE_CIPSOV4:
			cipso_v4_doi_putdef(entry->type_def.cipsov4);
			break;
		}
		call_rcu(&entry->rcu, netlbl_domhsh_free_entry);
	}

	return ret_val;
}

/**
 * netlbl_domhsh_remove - Removes an entry from the domain hash table
 * @domain: the domain to remove
 * @audit_info: NetLabel audit information
 *
 * Description:
 * Removes an entry from the domain hash table and handles any updates to the
 * lower level protocol handler (i.e. CIPSO).  Returns zero on success,
 * negative on failure.
 *
 */
int netlbl_domhsh_remove(const char *domain, struct netlbl_audit *audit_info)
{
	int ret_val;
	struct netlbl_dom_map *entry;

	rcu_read_lock();
	if (domain)
		entry = netlbl_domhsh_search(domain);
	else
		entry = netlbl_domhsh_search_def(domain);
	ret_val = netlbl_domhsh_remove_entry(entry, audit_info);
	rcu_read_unlock();

	return ret_val;
}

/**
 * netlbl_domhsh_remove_default - Removes the default entry from the table
 * @audit_info: NetLabel audit information
 *
 * Description:
 * Removes/resets the default entry for the domain hash table and handles any
 * updates to the lower level protocol handler (i.e. CIPSO).  Returns zero on
 * success, non-zero on failure.
 *
 */
int netlbl_domhsh_remove_default(struct netlbl_audit *audit_info)
{
	return netlbl_domhsh_remove(NULL, audit_info);
}

/**
 * netlbl_domhsh_getentry - Get an entry from the domain hash table
 * @domain: the domain name to search for
 *
 * Description:
 * Look through the domain hash table searching for an entry to match @domain,
 * return a pointer to a copy of the entry or NULL.  The caller is responsibile
 * for ensuring that rcu_read_[un]lock() is called.
 *
 */
struct netlbl_dom_map *netlbl_domhsh_getentry(const char *domain)
{
	return netlbl_domhsh_search_def(domain);
}

/**
 * netlbl_domhsh_walk - Iterate through the domain mapping hash table
 * @skip_bkt: the number of buckets to skip at the start
 * @skip_chain: the number of entries to skip in the first iterated bucket
 * @callback: callback for each entry
 * @cb_arg: argument for the callback function
 *
 * Description:
 * Interate over the domain mapping hash table, skipping the first @skip_bkt
 * buckets and @skip_chain entries.  For each entry in the table call
 * @callback, if @callback returns a negative value stop 'walking' through the
 * table and return.  Updates the values in @skip_bkt and @skip_chain on
 * return.  Returns zero on succcess, negative values on failure.
 *
 */
int netlbl_domhsh_walk(u32 *skip_bkt,
		     u32 *skip_chain,
		     int (*callback) (struct netlbl_dom_map *entry, void *arg),
		     void *cb_arg)
{
	int ret_val = -ENOENT;
	u32 iter_bkt;
	struct list_head *iter_list;
	struct netlbl_dom_map *iter_entry;
	u32 chain_cnt = 0;

	rcu_read_lock();
	for (iter_bkt = *skip_bkt;
	     iter_bkt < rcu_dereference(netlbl_domhsh)->size;
	     iter_bkt++, chain_cnt = 0) {
		iter_list = &rcu_dereference(netlbl_domhsh)->tbl[iter_bkt];
		list_for_each_entry_rcu(iter_entry, iter_list, list)
			if (iter_entry->valid) {
				if (chain_cnt++ < *skip_chain)
					continue;
				ret_val = callback(iter_entry, cb_arg);
				if (ret_val < 0) {
					chain_cnt--;
					goto walk_return;
				}
			}
	}

walk_return:
	rcu_read_unlock();
	*skip_bkt = iter_bkt;
	*skip_chain = chain_cnt;
	return ret_val;
}
Commit	Line	Data
d15c345f PM	1	/*
	2	* NetLabel Domain Hash Table
	3	*
	4	* This file manages the domain hash table that NetLabel uses to determine
	5	* which network labeling protocol to use for a given domain. The NetLabel
	6	* system manages static and dynamic label mappings for network protocols such
	7	* as CIPSO and RIPSO.
	8	*
	9	* Author: Paul Moore <paul.moore@hp.com>
	10	*
	11	*/
	12
	13	/*
	14	* (c) Copyright Hewlett-Packard Development Company, L.P., 2006
	15	*
	16	* This program is free software; you can redistribute it and/or modify
	17	* it under the terms of the GNU General Public License as published by
	18	* the Free Software Foundation; either version 2 of the License, or
	19	* (at your option) any later version.
	20	*
	21	* This program is distributed in the hope that it will be useful,
	22	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	23	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
	24	* the GNU General Public License for more details.
	25	*
	26	* You should have received a copy of the GNU General Public License
	27	* along with this program; if not, write to the Free Software
	28	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	29	*
	30	*/
	31
	32	#include <linux/types.h>
82524746	33	#include <linux/rculist.h>
d15c345f PM	34	#include <linux/skbuff.h>
	35	#include <linux/spinlock.h>
	36	#include <linux/string.h>
32f50cde	37	#include <linux/audit.h>
d15c345f PM	38	#include <net/netlabel.h>
	39	#include <net/cipso_ipv4.h>
	40	#include <asm/bug.h>
	41
	42	#include "netlabel_mgmt.h"
	43	#include "netlabel_domainhash.h"
32f50cde	44	#include "netlabel_user.h"
d15c345f PM	45
	46	struct netlbl_domhsh_tbl {
	47	struct list_head *tbl;
	48	u32 size;
	49	};
	50
	51	/* Domain hash table */
	52	/* XXX - updates should be so rare that having one spinlock for the entire
	53	* hash table should be okay */
8ce11e6a	54	static DEFINE_SPINLOCK(netlbl_domhsh_lock);
d15c345f	55	static struct netlbl_domhsh_tbl *netlbl_domhsh = NULL;
d15c345f PM	56	static struct netlbl_dom_map *netlbl_domhsh_def = NULL;
	57
	58	/*
	59	* Domain Hash Table Helper Functions
	60	*/
	61
	62	/**
	63	* netlbl_domhsh_free_entry - Frees a domain hash table entry
	64	* @entry: the entry's RCU field
	65	*
	66	* Description:
	67	* This function is designed to be used as a callback to the call_rcu()
	68	* function so that the memory allocated to a hash table entry can be released
	69	* safely.
	70	*
	71	*/
	72	static void netlbl_domhsh_free_entry(struct rcu_head *entry)
	73	{
	74	struct netlbl_dom_map *ptr;
	75
	76	ptr = container_of(entry, struct netlbl_dom_map, rcu);
	77	kfree(ptr->domain);
	78	kfree(ptr);
	79	}
	80
	81	/**
	82	* netlbl_domhsh_hash - Hashing function for the domain hash table
	83	* @domain: the domain name to hash
	84	*
	85	* Description:
	86	* This is the hashing function for the domain hash table, it returns the
	87	* correct bucket number for the domain. The caller is responsibile for
	88	* calling the rcu_read_[un]lock() functions.
	89	*
	90	*/
	91	static u32 netlbl_domhsh_hash(const char *key)
	92	{
	93	u32 iter;
	94	u32 val;
	95	u32 len;
	96
	97	/* This is taken (with slight modification) from
	98	* security/selinux/ss/symtab.c:symhash() */
	99
	100	for (iter = 0, val = 0, len = strlen(key); iter < len; iter++)
	101	val = (val << 4 \| (val >> (8 * sizeof(u32) - 4))) ^ key[iter];
	102	return val & (rcu_dereference(netlbl_domhsh)->size - 1);
	103	}
	104
	105	/**
	106	* netlbl_domhsh_search - Search for a domain entry
	107	* @domain: the domain
d15c345f PM	108	*
	109	* Description:
	110	* Searches the domain hash table and returns a pointer to the hash table
b64397e0 PM	111	* entry if found, otherwise NULL is returned. The caller is responsibile for
b64397e0 PM	112	* the rcu hash table locks (i.e. the caller much call rcu_read_[un]lock()).
d15c345f PM	113	*
d15c345f PM	114	*/
b64397e0	115	static struct netlbl_dom_map netlbl_domhsh_search(const char domain)
d15c345f PM	116	{
d15c345f PM	117	u32 bkt;
56196701	118	struct list_head *bkt_list;
d15c345f PM	119	struct netlbl_dom_map *iter;
	120
	121	if (domain != NULL) {
	122	bkt = netlbl_domhsh_hash(domain);
56196701 PM	123	bkt_list = &rcu_dereference(netlbl_domhsh)->tbl[bkt];
56196701 PM	124	list_for_each_entry_rcu(iter, bkt_list, list)
d15c345f PM	125	if (iter->valid && strcmp(iter->domain, domain) == 0)
	126	return iter;
	127	}
	128
b64397e0 PM	129	return NULL;
	130	}
	131
	132	/**
	133	* netlbl_domhsh_search_def - Search for a domain entry
	134	* @domain: the domain
	135	* @def: return default if no match is found
	136	*
	137	* Description:
	138	* Searches the domain hash table and returns a pointer to the hash table
	139	* entry if an exact match is found, if an exact match is not present in the
	140	* hash table then the default entry is returned if valid otherwise NULL is
	141	* returned. The caller is responsibile for the rcu hash table locks
	142	* (i.e. the caller much call rcu_read_[un]lock()).
	143	*
	144	*/
	145	static struct netlbl_dom_map netlbl_domhsh_search_def(const char domain)
	146	{
	147	struct netlbl_dom_map *entry;
	148
	149	entry = netlbl_domhsh_search(domain);
	150	if (entry == NULL) {
	151	entry = rcu_dereference(netlbl_domhsh_def);
4c3a0a25 PE	152	if (entry != NULL && !entry->valid)
4c3a0a25 PE	153	entry = NULL;
d15c345f PM	154	}
d15c345f PM	155
4c3a0a25	156	return entry;
d15c345f PM	157	}
	158
	159	/*
	160	* Domain Hash Table Functions
	161	*/
	162
	163	/**
	164	* netlbl_domhsh_init - Init for the domain hash
	165	* @size: the number of bits to use for the hash buckets
	166	*
	167	* Description:
	168	* Initializes the domain hash table, should be called only by
	169	* netlbl_user_init() during initialization. Returns zero on success, non-zero
	170	* values on error.
	171	*
	172	*/
05705e4e	173	int __init netlbl_domhsh_init(u32 size)
d15c345f PM	174	{
	175	u32 iter;
	176	struct netlbl_domhsh_tbl *hsh_tbl;
	177
	178	if (size == 0)
	179	return -EINVAL;
	180
	181	hsh_tbl = kmalloc(sizeof(*hsh_tbl), GFP_KERNEL);
	182	if (hsh_tbl == NULL)
	183	return -ENOMEM;
	184	hsh_tbl->size = 1 << size;
	185	hsh_tbl->tbl = kcalloc(hsh_tbl->size,
	186	sizeof(struct list_head),
	187	GFP_KERNEL);
	188	if (hsh_tbl->tbl == NULL) {
	189	kfree(hsh_tbl);
	190	return -ENOMEM;
	191	}
	192	for (iter = 0; iter < hsh_tbl->size; iter++)
	193	INIT_LIST_HEAD(&hsh_tbl->tbl[iter]);
	194
d15c345f PM	195	spin_lock(&netlbl_domhsh_lock);
	196	rcu_assign_pointer(netlbl_domhsh, hsh_tbl);
	197	spin_unlock(&netlbl_domhsh_lock);
d15c345f PM	198
	199	return 0;
	200	}
	201
	202	/**
	203	* netlbl_domhsh_add - Adds a entry to the domain hash table
	204	* @entry: the entry to add
95d4e6be	205	* @audit_info: NetLabel audit information
d15c345f PM	206	*
	207	* Description:
	208	* Adds a new entry to the domain hash table and handles any updates to the
	209	* lower level protocol handler (i.e. CIPSO). Returns zero on success,
	210	* negative on failure.
	211	*
	212	*/
95d4e6be PM	213	int netlbl_domhsh_add(struct netlbl_dom_map *entry,
95d4e6be PM	214	struct netlbl_audit *audit_info)
d15c345f PM	215	{
	216	int ret_val;
	217	u32 bkt;
32f50cde	218	struct audit_buffer *audit_buf;
d15c345f	219
d15c345f PM	220	entry->valid = 1;
	221	INIT_RCU_HEAD(&entry->rcu);
	222
d15c345f	223	rcu_read_lock();
1c3fad93	224	spin_lock(&netlbl_domhsh_lock);
d15c345f PM	225	if (entry->domain != NULL) {
d15c345f PM	226	bkt = netlbl_domhsh_hash(entry->domain);
b64397e0	227	if (netlbl_domhsh_search(entry->domain) == NULL)
d15c345f	228	list_add_tail_rcu(&entry->list,
3482fd90	229	&rcu_dereference(netlbl_domhsh)->tbl[bkt]);
d15c345f PM	230	else
d15c345f PM	231	ret_val = -EEXIST;
4be2700f	232	} else {
d15c345f	233	INIT_LIST_HEAD(&entry->list);
d15c345f PM	234	if (rcu_dereference(netlbl_domhsh_def) == NULL)
	235	rcu_assign_pointer(netlbl_domhsh_def, entry);
	236	else
	237	ret_val = -EEXIST;
4be2700f	238	}
1c3fad93	239	spin_unlock(&netlbl_domhsh_lock);
95d4e6be	240	audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_ADD, audit_info);
de64688f	241	if (audit_buf != NULL) {
95d4e6be	242	audit_log_format(audit_buf,
de64688f PM	243	" nlbl_domain=%s",
	244	entry->domain ? entry->domain : "(default)");
	245	switch (entry->type) {
	246	case NETLBL_NLTYPE_UNLABELED:
	247	audit_log_format(audit_buf, " nlbl_protocol=unlbl");
	248	break;
	249	case NETLBL_NLTYPE_CIPSOV4:
	250	audit_log_format(audit_buf,
	251	" nlbl_protocol=cipsov4 cipso_doi=%u",
	252	entry->type_def.cipsov4->doi);
	253	break;
	254	}
	255	audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
	256	audit_log_end(audit_buf);
32f50cde	257	}
d15c345f PM	258	rcu_read_unlock();
d15c345f PM	259
d15c345f PM	260	return ret_val;
	261	}
	262
	263	/**
	264	* netlbl_domhsh_add_default - Adds the default entry to the domain hash table
	265	* @entry: the entry to add
95d4e6be	266	* @audit_info: NetLabel audit information
d15c345f PM	267	*
	268	* Description:
	269	* Adds a new default entry to the domain hash table and handles any updates
	270	* to the lower level protocol handler (i.e. CIPSO). Returns zero on success,
	271	* negative on failure.
	272	*
	273	*/
95d4e6be PM	274	int netlbl_domhsh_add_default(struct netlbl_dom_map *entry,
95d4e6be PM	275	struct netlbl_audit *audit_info)
d15c345f	276	{
95d4e6be	277	return netlbl_domhsh_add(entry, audit_info);
d15c345f PM	278	}
	279
	280	/**
b1edeb10 PM	281	* netlbl_domhsh_remove_entry - Removes a given entry from the domain table
b1edeb10 PM	282	* @entry: the entry to remove
95d4e6be	283	* @audit_info: NetLabel audit information
d15c345f PM	284	*
	285	* Description:
	286	* Removes an entry from the domain hash table and handles any updates to the
b1edeb10 PM	287	* lower level protocol handler (i.e. CIPSO). Caller is responsible for
	288	* ensuring that the RCU read lock is held. Returns zero on success, negative
	289	* on failure.
d15c345f PM	290	*
d15c345f PM	291	*/
b1edeb10 PM	292	int netlbl_domhsh_remove_entry(struct netlbl_dom_map *entry,
b1edeb10 PM	293	struct netlbl_audit *audit_info)
d15c345f	294	{
b1edeb10	295	int ret_val = 0;
32f50cde	296	struct audit_buffer *audit_buf;
d15c345f	297
d15c345f	298	if (entry == NULL)
b1edeb10 PM	299	return -ENOENT;
b1edeb10 PM	300
1c3fad93 PM	301	spin_lock(&netlbl_domhsh_lock);
	302	if (entry->valid) {
	303	entry->valid = 0;
	304	if (entry != rcu_dereference(netlbl_domhsh_def))
d15c345f	305	list_del_rcu(&entry->list);
1c3fad93	306	else
d15c345f	307	rcu_assign_pointer(netlbl_domhsh_def, NULL);
b1edeb10 PM	308	} else
b1edeb10 PM	309	ret_val = -ENOENT;
1c3fad93	310	spin_unlock(&netlbl_domhsh_lock);
32f50cde	311
95d4e6be	312	audit_buf = netlbl_audit_start_common(AUDIT_MAC_MAP_DEL, audit_info);
de64688f PM	313	if (audit_buf != NULL) {
	314	audit_log_format(audit_buf,
	315	" nlbl_domain=%s res=%u",
	316	entry->domain ? entry->domain : "(default)",
	317	ret_val == 0 ? 1 : 0);
	318	audit_log_end(audit_buf);
	319	}
95d4e6be	320
b1edeb10 PM	321	if (ret_val == 0) {
	322	switch (entry->type) {
	323	case NETLBL_NLTYPE_CIPSOV4:
	324	cipso_v4_doi_putdef(entry->type_def.cipsov4);
	325	break;
	326	}
4be2700f	327	call_rcu(&entry->rcu, netlbl_domhsh_free_entry);
b1edeb10 PM	328	}
	329
	330	return ret_val;
	331	}
	332
	333	/**
	334	* netlbl_domhsh_remove - Removes an entry from the domain hash table
	335	* @domain: the domain to remove
	336	* @audit_info: NetLabel audit information
	337	*
	338	* Description:
	339	* Removes an entry from the domain hash table and handles any updates to the
	340	* lower level protocol handler (i.e. CIPSO). Returns zero on success,
	341	* negative on failure.
	342	*
	343	*/
	344	int netlbl_domhsh_remove(const char domain, struct netlbl_audit audit_info)
	345	{
	346	int ret_val;
	347	struct netlbl_dom_map *entry;
	348
	349	rcu_read_lock();
	350	if (domain)
	351	entry = netlbl_domhsh_search(domain);
	352	else
	353	entry = netlbl_domhsh_search_def(domain);
	354	ret_val = netlbl_domhsh_remove_entry(entry, audit_info);
	355	rcu_read_unlock();
	356
d15c345f PM	357	return ret_val;
	358	}
	359
	360	/**
	361	* netlbl_domhsh_remove_default - Removes the default entry from the table
95d4e6be	362	* @audit_info: NetLabel audit information
d15c345f PM	363	*
	364	* Description:
	365	* Removes/resets the default entry for the domain hash table and handles any
	366	* updates to the lower level protocol handler (i.e. CIPSO). Returns zero on
	367	* success, non-zero on failure.
	368	*
	369	*/
95d4e6be	370	int netlbl_domhsh_remove_default(struct netlbl_audit *audit_info)
d15c345f	371	{
95d4e6be	372	return netlbl_domhsh_remove(NULL, audit_info);
d15c345f PM	373	}
	374
	375	/**
	376	* netlbl_domhsh_getentry - Get an entry from the domain hash table
	377	* @domain: the domain name to search for
	378	*
	379	* Description:
	380	* Look through the domain hash table searching for an entry to match @domain,
	381	* return a pointer to a copy of the entry or NULL. The caller is responsibile
	382	* for ensuring that rcu_read_[un]lock() is called.
	383	*
	384	*/
	385	struct netlbl_dom_map netlbl_domhsh_getentry(const char domain)
	386	{
b64397e0	387	return netlbl_domhsh_search_def(domain);
d15c345f PM	388	}
	389
	390	/**
fcd48280 PM	391	* netlbl_domhsh_walk - Iterate through the domain mapping hash table
	392	* @skip_bkt: the number of buckets to skip at the start
	393	* @skip_chain: the number of entries to skip in the first iterated bucket
	394	* @callback: callback for each entry
	395	* @cb_arg: argument for the callback function
d15c345f PM	396	*
d15c345f PM	397	* Description:
fcd48280 PM	398	* Interate over the domain mapping hash table, skipping the first @skip_bkt
	399	* buckets and @skip_chain entries. For each entry in the table call
	400	* @callback, if @callback returns a negative value stop 'walking' through the
	401	* table and return. Updates the values in @skip_bkt and @skip_chain on
	402	* return. Returns zero on succcess, negative values on failure.
d15c345f PM	403	*
d15c345f PM	404	*/
fcd48280 PM	405	int netlbl_domhsh_walk(u32 *skip_bkt,
	406	u32 *skip_chain,
	407	int (callback) (struct netlbl_dom_map entry, void *arg),
	408	void *cb_arg)
d15c345f	409	{
fcd48280 PM	410	int ret_val = -ENOENT;
fcd48280 PM	411	u32 iter_bkt;
56196701	412	struct list_head *iter_list;
fcd48280 PM	413	struct netlbl_dom_map *iter_entry;
fcd48280 PM	414	u32 chain_cnt = 0;
d15c345f	415
d15c345f	416	rcu_read_lock();
fcd48280 PM	417	for (iter_bkt = *skip_bkt;
	418	iter_bkt < rcu_dereference(netlbl_domhsh)->size;
	419	iter_bkt++, chain_cnt = 0) {
56196701 PM	420	iter_list = &rcu_dereference(netlbl_domhsh)->tbl[iter_bkt];
56196701 PM	421	list_for_each_entry_rcu(iter_entry, iter_list, list)
fcd48280 PM	422	if (iter_entry->valid) {
	423	if (chain_cnt++ < *skip_chain)
	424	continue;
	425	ret_val = callback(iter_entry, cb_arg);
	426	if (ret_val < 0) {
	427	chain_cnt--;
	428	goto walk_return;
	429	}
d15c345f	430	}
fcd48280	431	}
d15c345f	432
fcd48280	433	walk_return:
d15c345f	434	rcu_read_unlock();
fcd48280 PM	435	*skip_bkt = iter_bkt;
	436	*skip_chain = chain_cnt;
	437	return ret_val;
d15c345f	438	}