[mirror_ubuntu-bionic-kernel.git] / net / wireless / lib80211.c

/*
 * lib80211 -- common bits for IEEE802.11 drivers
 *
 * Copyright(c) 2008 John W. Linville <linville@tuxdriver.com>
 *
 * Portions copied from old ieee80211 component, w/ original copyright
 * notices below:
 *
 * Host AP crypto routines
 *
 * Copyright (c) 2002-2003, Jouni Malinen <j@w1.fi>
 * Portions Copyright (C) 2004, Intel Corporation <jketreno@linux.intel.com>
 *
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/ctype.h>
#include <linux/ieee80211.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/string.h>

#include <net/lib80211.h>

#define DRV_NAME        "lib80211"

#define DRV_DESCRIPTION	"common routines for IEEE802.11 drivers"

MODULE_DESCRIPTION(DRV_DESCRIPTION);
MODULE_AUTHOR("John W. Linville <linville@tuxdriver.com>");
MODULE_LICENSE("GPL");

struct lib80211_crypto_alg {
	struct list_head list;
	struct lib80211_crypto_ops *ops;
};

static LIST_HEAD(lib80211_crypto_algs);
static DEFINE_SPINLOCK(lib80211_crypto_lock);

static void lib80211_crypt_deinit_entries(struct lib80211_crypt_info *info,
					  int force);
static void lib80211_crypt_quiescing(struct lib80211_crypt_info *info);
static void lib80211_crypt_deinit_handler(struct timer_list *t);

int lib80211_crypt_info_init(struct lib80211_crypt_info *info, char *name,
				spinlock_t *lock)
{
	memset(info, 0, sizeof(*info));

	info->name = name;
	info->lock = lock;

	INIT_LIST_HEAD(&info->crypt_deinit_list);
	timer_setup(&info->crypt_deinit_timer, lib80211_crypt_deinit_handler,
		    0);

	return 0;
}
EXPORT_SYMBOL(lib80211_crypt_info_init);

void lib80211_crypt_info_free(struct lib80211_crypt_info *info)
{
	int i;

        lib80211_crypt_quiescing(info);
        del_timer_sync(&info->crypt_deinit_timer);
        lib80211_crypt_deinit_entries(info, 1);

        for (i = 0; i < NUM_WEP_KEYS; i++) {
                struct lib80211_crypt_data *crypt = info->crypt[i];
                if (crypt) {
                        if (crypt->ops) {
                                crypt->ops->deinit(crypt->priv);
                                module_put(crypt->ops->owner);
                        }
                        kfree(crypt);
                        info->crypt[i] = NULL;
                }
        }
}
EXPORT_SYMBOL(lib80211_crypt_info_free);

static void lib80211_crypt_deinit_entries(struct lib80211_crypt_info *info,
					  int force)
{
	struct lib80211_crypt_data *entry, *next;
	unsigned long flags;

	spin_lock_irqsave(info->lock, flags);
	list_for_each_entry_safe(entry, next, &info->crypt_deinit_list, list) {
		if (atomic_read(&entry->refcnt) != 0 && !force)
			continue;

		list_del(&entry->list);

		if (entry->ops) {
			entry->ops->deinit(entry->priv);
			module_put(entry->ops->owner);
		}
		kfree(entry);
	}
	spin_unlock_irqrestore(info->lock, flags);
}

/* After this, crypt_deinit_list won't accept new members */
static void lib80211_crypt_quiescing(struct lib80211_crypt_info *info)
{
	unsigned long flags;

	spin_lock_irqsave(info->lock, flags);
	info->crypt_quiesced = 1;
	spin_unlock_irqrestore(info->lock, flags);
}

static void lib80211_crypt_deinit_handler(struct timer_list *t)
{
	struct lib80211_crypt_info *info = from_timer(info, t,
						      crypt_deinit_timer);
	unsigned long flags;

	lib80211_crypt_deinit_entries(info, 0);

	spin_lock_irqsave(info->lock, flags);
	if (!list_empty(&info->crypt_deinit_list) && !info->crypt_quiesced) {
		printk(KERN_DEBUG "%s: entries remaining in delayed crypt "
		       "deletion list\n", info->name);
		info->crypt_deinit_timer.expires = jiffies + HZ;
		add_timer(&info->crypt_deinit_timer);
	}
	spin_unlock_irqrestore(info->lock, flags);
}

void lib80211_crypt_delayed_deinit(struct lib80211_crypt_info *info,
				    struct lib80211_crypt_data **crypt)
{
	struct lib80211_crypt_data *tmp;
	unsigned long flags;

	if (*crypt == NULL)
		return;

	tmp = *crypt;
	*crypt = NULL;

	/* must not run ops->deinit() while there may be pending encrypt or
	 * decrypt operations. Use a list of delayed deinits to avoid needing
	 * locking. */

	spin_lock_irqsave(info->lock, flags);
	if (!info->crypt_quiesced) {
		list_add(&tmp->list, &info->crypt_deinit_list);
		if (!timer_pending(&info->crypt_deinit_timer)) {
			info->crypt_deinit_timer.expires = jiffies + HZ;
			add_timer(&info->crypt_deinit_timer);
		}
	}
	spin_unlock_irqrestore(info->lock, flags);
}
EXPORT_SYMBOL(lib80211_crypt_delayed_deinit);

int lib80211_register_crypto_ops(struct lib80211_crypto_ops *ops)
{
	unsigned long flags;
	struct lib80211_crypto_alg *alg;

	alg = kzalloc(sizeof(*alg), GFP_KERNEL);
	if (alg == NULL)
		return -ENOMEM;

	alg->ops = ops;

	spin_lock_irqsave(&lib80211_crypto_lock, flags);
	list_add(&alg->list, &lib80211_crypto_algs);
	spin_unlock_irqrestore(&lib80211_crypto_lock, flags);

	printk(KERN_DEBUG "lib80211_crypt: registered algorithm '%s'\n",
	       ops->name);

	return 0;
}
EXPORT_SYMBOL(lib80211_register_crypto_ops);

int lib80211_unregister_crypto_ops(struct lib80211_crypto_ops *ops)
{
	struct lib80211_crypto_alg *alg;
	unsigned long flags;

	spin_lock_irqsave(&lib80211_crypto_lock, flags);
	list_for_each_entry(alg, &lib80211_crypto_algs, list) {
		if (alg->ops == ops)
			goto found;
	}
	spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
	return -EINVAL;

      found:
	printk(KERN_DEBUG "lib80211_crypt: unregistered algorithm '%s'\n",
	       ops->name);
	list_del(&alg->list);
	spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
	kfree(alg);
	return 0;
}
EXPORT_SYMBOL(lib80211_unregister_crypto_ops);

struct lib80211_crypto_ops *lib80211_get_crypto_ops(const char *name)
{
	struct lib80211_crypto_alg *alg;
	unsigned long flags;

	spin_lock_irqsave(&lib80211_crypto_lock, flags);
	list_for_each_entry(alg, &lib80211_crypto_algs, list) {
		if (strcmp(alg->ops->name, name) == 0)
			goto found;
	}
	spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
	return NULL;

      found:
	spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
	return alg->ops;
}
EXPORT_SYMBOL(lib80211_get_crypto_ops);

static void *lib80211_crypt_null_init(int keyidx)
{
	return (void *)1;
}

static void lib80211_crypt_null_deinit(void *priv)
{
}

static struct lib80211_crypto_ops lib80211_crypt_null = {
	.name = "NULL",
	.init = lib80211_crypt_null_init,
	.deinit = lib80211_crypt_null_deinit,
	.owner = THIS_MODULE,
};

static int __init lib80211_init(void)
{
	pr_info(DRV_DESCRIPTION "\n");
	return lib80211_register_crypto_ops(&lib80211_crypt_null);
}

static void __exit lib80211_exit(void)
{
	lib80211_unregister_crypto_ops(&lib80211_crypt_null);
	BUG_ON(!list_empty(&lib80211_crypto_algs));
}

module_init(lib80211_init);
module_exit(lib80211_exit);
Commit	Line	Data
7e272fcf JL	1	/*
	2	* lib80211 -- common bits for IEEE802.11 drivers
	3	*
	4	* Copyright(c) 2008 John W. Linville <linville@tuxdriver.com>
	5	*
274bfb8d JL	6	* Portions copied from old ieee80211 component, w/ original copyright
	7	* notices below:
	8	*
	9	* Host AP crypto routines
	10	*
	11	* Copyright (c) 2002-2003, Jouni Malinen <j@w1.fi>
	12	* Portions Copyright (C) 2004, Intel Corporation <jketreno@linux.intel.com>
	13	*
7e272fcf JL	14	*/
7e272fcf JL	15
e9c0268f JP	16	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
e9c0268f JP	17
7e272fcf	18	#include <linux/module.h>
2819f8ad	19	#include <linux/ctype.h>
7e272fcf	20	#include <linux/ieee80211.h>
274bfb8d JL	21	#include <linux/errno.h>
	22	#include <linux/init.h>
	23	#include <linux/slab.h>
	24	#include <linux/string.h>
7e272fcf JL	25
	26	#include <net/lib80211.h>
	27
	28	#define DRV_NAME "lib80211"
	29
	30	#define DRV_DESCRIPTION "common routines for IEEE802.11 drivers"
	31
	32	MODULE_DESCRIPTION(DRV_DESCRIPTION);
	33	MODULE_AUTHOR("John W. Linville <linville@tuxdriver.com>");
	34	MODULE_LICENSE("GPL");
	35
274bfb8d JL	36	struct lib80211_crypto_alg {
	37	struct list_head list;
	38	struct lib80211_crypto_ops *ops;
	39	};
	40
	41	static LIST_HEAD(lib80211_crypto_algs);
	42	static DEFINE_SPINLOCK(lib80211_crypto_lock);
	43
9d630c77 PR	44	static void lib80211_crypt_deinit_entries(struct lib80211_crypt_info *info,
	45	int force);
	46	static void lib80211_crypt_quiescing(struct lib80211_crypt_info *info);
e99e88a9	47	static void lib80211_crypt_deinit_handler(struct timer_list *t);
9d630c77	48
2ba4b32e JL	49	int lib80211_crypt_info_init(struct lib80211_crypt_info info, char name,
	50	spinlock_t *lock)
	51	{
	52	memset(info, 0, sizeof(*info));
	53
	54	info->name = name;
	55	info->lock = lock;
	56
	57	INIT_LIST_HEAD(&info->crypt_deinit_list);
e99e88a9 KC	58	timer_setup(&info->crypt_deinit_timer, lib80211_crypt_deinit_handler,
e99e88a9 KC	59	0);
2ba4b32e JL	60
	61	return 0;
	62	}
	63	EXPORT_SYMBOL(lib80211_crypt_info_init);
	64
	65	void lib80211_crypt_info_free(struct lib80211_crypt_info *info)
	66	{
	67	int i;
	68
	69	lib80211_crypt_quiescing(info);
	70	del_timer_sync(&info->crypt_deinit_timer);
	71	lib80211_crypt_deinit_entries(info, 1);
	72
	73	for (i = 0; i < NUM_WEP_KEYS; i++) {
	74	struct lib80211_crypt_data *crypt = info->crypt[i];
	75	if (crypt) {
	76	if (crypt->ops) {
	77	crypt->ops->deinit(crypt->priv);
	78	module_put(crypt->ops->owner);
	79	}
	80	kfree(crypt);
	81	info->crypt[i] = NULL;
	82	}
	83	}
	84	}
	85	EXPORT_SYMBOL(lib80211_crypt_info_free);
	86
9d630c77 PR	87	static void lib80211_crypt_deinit_entries(struct lib80211_crypt_info *info,
9d630c77 PR	88	int force)
7e272fcf	89	{
274bfb8d JL	90	struct lib80211_crypt_data entry, next;
	91	unsigned long flags;
	92
	93	spin_lock_irqsave(info->lock, flags);
	94	list_for_each_entry_safe(entry, next, &info->crypt_deinit_list, list) {
	95	if (atomic_read(&entry->refcnt) != 0 && !force)
	96	continue;
	97
	98	list_del(&entry->list);
	99
	100	if (entry->ops) {
	101	entry->ops->deinit(entry->priv);
	102	module_put(entry->ops->owner);
	103	}
	104	kfree(entry);
	105	}
	106	spin_unlock_irqrestore(info->lock, flags);
	107	}
274bfb8d JL	108
274bfb8d JL	109	/* After this, crypt_deinit_list won't accept new members */
9d630c77	110	static void lib80211_crypt_quiescing(struct lib80211_crypt_info *info)
274bfb8d JL	111	{
	112	unsigned long flags;
	113
	114	spin_lock_irqsave(info->lock, flags);
	115	info->crypt_quiesced = 1;
	116	spin_unlock_irqrestore(info->lock, flags);
	117	}
274bfb8d	118
e99e88a9	119	static void lib80211_crypt_deinit_handler(struct timer_list *t)
274bfb8d	120	{
e99e88a9 KC	121	struct lib80211_crypt_info *info = from_timer(info, t,
e99e88a9 KC	122	crypt_deinit_timer);
274bfb8d JL	123	unsigned long flags;
	124
	125	lib80211_crypt_deinit_entries(info, 0);
	126
	127	spin_lock_irqsave(info->lock, flags);
	128	if (!list_empty(&info->crypt_deinit_list) && !info->crypt_quiesced) {
	129	printk(KERN_DEBUG "%s: entries remaining in delayed crypt "
	130	"deletion list\n", info->name);
	131	info->crypt_deinit_timer.expires = jiffies + HZ;
	132	add_timer(&info->crypt_deinit_timer);
	133	}
	134	spin_unlock_irqrestore(info->lock, flags);
	135	}
274bfb8d JL	136
	137	void lib80211_crypt_delayed_deinit(struct lib80211_crypt_info *info,
	138	struct lib80211_crypt_data **crypt)
	139	{
	140	struct lib80211_crypt_data *tmp;
	141	unsigned long flags;
	142
	143	if (*crypt == NULL)
	144	return;
	145
	146	tmp = *crypt;
	147	*crypt = NULL;
	148
	149	/* must not run ops->deinit() while there may be pending encrypt or
	150	* decrypt operations. Use a list of delayed deinits to avoid needing
	151	* locking. */
	152
	153	spin_lock_irqsave(info->lock, flags);
	154	if (!info->crypt_quiesced) {
	155	list_add(&tmp->list, &info->crypt_deinit_list);
	156	if (!timer_pending(&info->crypt_deinit_timer)) {
	157	info->crypt_deinit_timer.expires = jiffies + HZ;
	158	add_timer(&info->crypt_deinit_timer);
	159	}
	160	}
	161	spin_unlock_irqrestore(info->lock, flags);
	162	}
	163	EXPORT_SYMBOL(lib80211_crypt_delayed_deinit);
	164
	165	int lib80211_register_crypto_ops(struct lib80211_crypto_ops *ops)
	166	{
	167	unsigned long flags;
	168	struct lib80211_crypto_alg *alg;
	169
	170	alg = kzalloc(sizeof(*alg), GFP_KERNEL);
	171	if (alg == NULL)
	172	return -ENOMEM;
	173
	174	alg->ops = ops;
	175
	176	spin_lock_irqsave(&lib80211_crypto_lock, flags);
	177	list_add(&alg->list, &lib80211_crypto_algs);
	178	spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
	179
	180	printk(KERN_DEBUG "lib80211_crypt: registered algorithm '%s'\n",
	181	ops->name);
	182
	183	return 0;
	184	}
	185	EXPORT_SYMBOL(lib80211_register_crypto_ops);
	186
	187	int lib80211_unregister_crypto_ops(struct lib80211_crypto_ops *ops)
	188	{
	189	struct lib80211_crypto_alg *alg;
	190	unsigned long flags;
	191
	192	spin_lock_irqsave(&lib80211_crypto_lock, flags);
	193	list_for_each_entry(alg, &lib80211_crypto_algs, list) {
	194	if (alg->ops == ops)
	195	goto found;
	196	}
	197	spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
	198	return -EINVAL;
	199
200	found:
e9c0268f JP	201	printk(KERN_DEBUG "lib80211_crypt: unregistered algorithm '%s'\n",
e9c0268f JP	202	ops->name);
274bfb8d JL	203	list_del(&alg->list);
	204	spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
	205	kfree(alg);
7e272fcf JL	206	return 0;
7e272fcf JL	207	}
274bfb8d JL	208	EXPORT_SYMBOL(lib80211_unregister_crypto_ops);
	209
	210	struct lib80211_crypto_ops lib80211_get_crypto_ops(const char name)
	211	{
	212	struct lib80211_crypto_alg *alg;
	213	unsigned long flags;
	214
	215	spin_lock_irqsave(&lib80211_crypto_lock, flags);
	216	list_for_each_entry(alg, &lib80211_crypto_algs, list) {
	217	if (strcmp(alg->ops->name, name) == 0)
	218	goto found;
	219	}
	220	spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
	221	return NULL;
	222
	223	found:
	224	spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
	225	return alg->ops;
	226	}
	227	EXPORT_SYMBOL(lib80211_get_crypto_ops);
	228
	229	static void *lib80211_crypt_null_init(int keyidx)
	230	{
	231	return (void *)1;
	232	}
	233
	234	static void lib80211_crypt_null_deinit(void *priv)
	235	{
	236	}
	237
	238	static struct lib80211_crypto_ops lib80211_crypt_null = {
	239	.name = "NULL",
	240	.init = lib80211_crypt_null_init,
	241	.deinit = lib80211_crypt_null_deinit,
	242	.owner = THIS_MODULE,
	243	};
	244
	245	static int __init lib80211_init(void)
	246	{
e9c0268f	247	pr_info(DRV_DESCRIPTION "\n");
274bfb8d JL	248	return lib80211_register_crypto_ops(&lib80211_crypt_null);
274bfb8d JL	249	}
7e272fcf	250
274bfb8d	251	static void __exit lib80211_exit(void)
7e272fcf	252	{
274bfb8d JL	253	lib80211_unregister_crypto_ops(&lib80211_crypt_null);
274bfb8d JL	254	BUG_ON(!list_empty(&lib80211_crypto_algs));
7e272fcf JL	255	}
7e272fcf JL	256
274bfb8d JL	257	module_init(lib80211_init);
274bfb8d JL	258	module_exit(lib80211_exit);