1/*
2 * Host AP crypto routines
3 *
4 * Copyright (c) 2002-2003, Jouni Malinen <jkmaline@cc.hut.fi>
5 * Portions Copyright (C) 2004, Intel Corporation <jketreno@linux.intel.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation. See README and COPYING for
10 * more details.
11 *
12 */
13
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/slab.h>
17#include <linux/string.h>
18#include <linux/errno.h>
19
20#include "rtllib.h"
21
22struct rtllib_crypto_alg {
23	struct list_head list;
24	struct lib80211_crypto_ops *ops;
25};
26
27
28struct rtllib_crypto {
29	struct list_head algs;
30	spinlock_t lock;
31};
32
33static struct rtllib_crypto *hcrypt;
34
35void rtllib_crypt_deinit_entries(struct lib80211_crypt_info *info,
36					   int force)
37{
38	struct list_head *ptr, *n;
39	struct lib80211_crypt_data *entry;
40
41	for (ptr = info->crypt_deinit_list.next, n = ptr->next;
42	     ptr != &info->crypt_deinit_list; ptr = n, n = ptr->next) {
43		entry = list_entry(ptr, struct lib80211_crypt_data, list);
44
45		if (atomic_read(&entry->refcnt) != 0 && !force)
46			continue;
47
48		list_del(ptr);
49
50		if (entry->ops)
51			entry->ops->deinit(entry->priv);
52		kfree(entry);
53	}
54}
55EXPORT_SYMBOL(rtllib_crypt_deinit_entries);
56
57void rtllib_crypt_deinit_handler(unsigned long data)
58{
59	struct lib80211_crypt_info *info = (struct lib80211_crypt_info *)data;
60	unsigned long flags;
61
62	spin_lock_irqsave(info->lock, flags);
63	rtllib_crypt_deinit_entries(info, 0);
64	if (!list_empty(&info->crypt_deinit_list)) {
65		printk(KERN_DEBUG
66		       "%s: entries remaining in delayed crypt deletion list\n",
67		       info->name);
68		info->crypt_deinit_timer.expires = jiffies + HZ;
69		add_timer(&info->crypt_deinit_timer);
70	}
71	spin_unlock_irqrestore(info->lock, flags);
72
73}
74EXPORT_SYMBOL(rtllib_crypt_deinit_handler);
75
76void rtllib_crypt_delayed_deinit(struct lib80211_crypt_info *info,
77				 struct lib80211_crypt_data **crypt)
78{
79	struct lib80211_crypt_data *tmp;
80	unsigned long flags;
81
82	if (*crypt == NULL)
83		return;
84
85	tmp = *crypt;
86	*crypt = NULL;
87
88	/* must not run ops->deinit() while there may be pending encrypt or
89	 * decrypt operations. Use a list of delayed deinits to avoid needing
90	 * locking.
91	 */
92
93	spin_lock_irqsave(info->lock, flags);
94	list_add(&tmp->list, &info->crypt_deinit_list);
95	if (!timer_pending(&info->crypt_deinit_timer)) {
96		info->crypt_deinit_timer.expires = jiffies + HZ;
97		add_timer(&info->crypt_deinit_timer);
98	}
99	spin_unlock_irqrestore(info->lock, flags);
100}
101EXPORT_SYMBOL(rtllib_crypt_delayed_deinit);
102
103int rtllib_register_crypto_ops(struct lib80211_crypto_ops *ops)
104{
105	unsigned long flags;
106	struct rtllib_crypto_alg *alg;
107
108	if (hcrypt == NULL)
109		return -1;
110
111	alg = kzalloc(sizeof(*alg), GFP_KERNEL);
112	if (alg == NULL)
113		return -ENOMEM;
114
115	alg->ops = ops;
116
117	spin_lock_irqsave(&hcrypt->lock, flags);
118	list_add(&alg->list, &hcrypt->algs);
119	spin_unlock_irqrestore(&hcrypt->lock, flags);
120
121	printk(KERN_DEBUG "rtllib_crypt: registered algorithm '%s'\n",
122	       ops->name);
123
124	return 0;
125}
126EXPORT_SYMBOL(rtllib_register_crypto_ops);
127
128int rtllib_unregister_crypto_ops(struct lib80211_crypto_ops *ops)
129{
130	unsigned long flags;
131	struct list_head *ptr;
132	struct rtllib_crypto_alg *del_alg = NULL;
133
134	if (hcrypt == NULL)
135		return -1;
136
137	spin_lock_irqsave(&hcrypt->lock, flags);
138	for (ptr = hcrypt->algs.next; ptr != &hcrypt->algs; ptr = ptr->next) {
139		struct rtllib_crypto_alg *alg =
140			(struct rtllib_crypto_alg *) ptr;
141		if (alg->ops == ops) {
142			list_del(&alg->list);
143			del_alg = alg;
144			break;
145		}
146	}
147	spin_unlock_irqrestore(&hcrypt->lock, flags);
148
149	if (del_alg) {
150		printk(KERN_DEBUG "rtllib_crypt: unregistered algorithm '%s'\n",
151		       ops->name);
152		kfree(del_alg);
153	}
154
155	return del_alg ? 0 : -1;
156}
157EXPORT_SYMBOL(rtllib_unregister_crypto_ops);
158
159
160struct lib80211_crypto_ops *rtllib_get_crypto_ops(const char *name)
161{
162	unsigned long flags;
163	struct list_head *ptr;
164	struct rtllib_crypto_alg *found_alg = NULL;
165
166	if (hcrypt == NULL)
167		return NULL;
168
169	spin_lock_irqsave(&hcrypt->lock, flags);
170	for (ptr = hcrypt->algs.next; ptr != &hcrypt->algs; ptr = ptr->next) {
171		struct rtllib_crypto_alg *alg =
172			(struct rtllib_crypto_alg *) ptr;
173		if (strcmp(alg->ops->name, name) == 0) {
174			found_alg = alg;
175			break;
176		}
177	}
178	spin_unlock_irqrestore(&hcrypt->lock, flags);
179
180	if (found_alg)
181		return found_alg->ops;
182	else
183		return NULL;
184}
185EXPORT_SYMBOL(rtllib_get_crypto_ops);
186
187
188static void *rtllib_crypt_null_init(int keyidx) { return (void *) 1; }
189static void rtllib_crypt_null_deinit(void *priv) {}
190
191static struct lib80211_crypto_ops rtllib_crypt_null = {
192	.name			= "NULL",
193	.init			= rtllib_crypt_null_init,
194	.deinit			= rtllib_crypt_null_deinit,
195	.encrypt_mpdu		= NULL,
196	.decrypt_mpdu		= NULL,
197	.encrypt_msdu		= NULL,
198	.decrypt_msdu		= NULL,
199	.set_key		= NULL,
200	.get_key		= NULL,
201	.extra_mpdu_prefix_len	= 0,
202	.extra_mpdu_postfix_len	= 0,
203	.extra_msdu_prefix_len	= 0,
204	.extra_msdu_postfix_len	= 0,
205	.owner			= THIS_MODULE,
206};
207
208
209int __init rtllib_crypto_init(void)
210{
211	int ret = -ENOMEM;
212
213	hcrypt = kzalloc(sizeof(*hcrypt), GFP_KERNEL);
214	if (!hcrypt)
215		goto out;
216
217	INIT_LIST_HEAD(&hcrypt->algs);
218	spin_lock_init(&hcrypt->lock);
219
220	ret = lib80211_register_crypto_ops(&rtllib_crypt_null);
221	if (ret < 0) {
222		kfree(hcrypt);
223		hcrypt = NULL;
224	}
225out:
226	return ret;
227}
228
229
230void __exit rtllib_crypto_deinit(void)
231{
232	struct list_head *ptr, *n;
233
234	if (hcrypt == NULL)
235		return;
236
237	for (ptr = hcrypt->algs.next, n = ptr->next; ptr != &hcrypt->algs;
238	     ptr = n, n = ptr->next) {
239		struct rtllib_crypto_alg *alg =
240			(struct rtllib_crypto_alg *) ptr;
241		list_del(ptr);
242		printk(KERN_DEBUG
243		       "rtllib_crypt: unregistered algorithm '%s' (deinit)\n",
244		       alg->ops->name);
245		kfree(alg);
246	}
247
248	kfree(hcrypt);
249}
250
251module_init(rtllib_crypto_init);
252module_exit(rtllib_crypto_deinit);
253
254MODULE_LICENSE("GPL");
255