nilfs2: segment constructor
[linux-2.6] / net / wireless / lib80211.c
1 /*
2  * lib80211 -- common bits for IEEE802.11 drivers
3  *
4  * Copyright(c) 2008 John W. Linville <linville@tuxdriver.com>
5  *
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  *
14  */
15
16 #include <linux/module.h>
17 #include <linux/ctype.h>
18 #include <linux/ieee80211.h>
19 #include <linux/errno.h>
20 #include <linux/init.h>
21 #include <linux/slab.h>
22 #include <linux/string.h>
23
24 #include <net/lib80211.h>
25
26 #define DRV_NAME        "lib80211"
27
28 #define DRV_DESCRIPTION "common routines for IEEE802.11 drivers"
29
30 MODULE_DESCRIPTION(DRV_DESCRIPTION);
31 MODULE_AUTHOR("John W. Linville <linville@tuxdriver.com>");
32 MODULE_LICENSE("GPL");
33
34 struct lib80211_crypto_alg {
35         struct list_head list;
36         struct lib80211_crypto_ops *ops;
37 };
38
39 static LIST_HEAD(lib80211_crypto_algs);
40 static DEFINE_SPINLOCK(lib80211_crypto_lock);
41
42 const char *print_ssid(char *buf, const char *ssid, u8 ssid_len)
43 {
44         const char *s = ssid;
45         char *d = buf;
46
47         ssid_len = min_t(u8, ssid_len, IEEE80211_MAX_SSID_LEN);
48         while (ssid_len--) {
49                 if (isprint(*s)) {
50                         *d++ = *s++;
51                         continue;
52                 }
53
54                 *d++ = '\\';
55                 if (*s == '\0')
56                         *d++ = '0';
57                 else if (*s == '\n')
58                         *d++ = 'n';
59                 else if (*s == '\r')
60                         *d++ = 'r';
61                 else if (*s == '\t')
62                         *d++ = 't';
63                 else if (*s == '\\')
64                         *d++ = '\\';
65                 else
66                         d += snprintf(d, 3, "%03o", *s);
67                 s++;
68         }
69         *d = '\0';
70         return buf;
71 }
72 EXPORT_SYMBOL(print_ssid);
73
74 int lib80211_crypt_info_init(struct lib80211_crypt_info *info, char *name,
75                                 spinlock_t *lock)
76 {
77         memset(info, 0, sizeof(*info));
78
79         info->name = name;
80         info->lock = lock;
81
82         INIT_LIST_HEAD(&info->crypt_deinit_list);
83         setup_timer(&info->crypt_deinit_timer, lib80211_crypt_deinit_handler,
84                         (unsigned long)info);
85
86         return 0;
87 }
88 EXPORT_SYMBOL(lib80211_crypt_info_init);
89
90 void lib80211_crypt_info_free(struct lib80211_crypt_info *info)
91 {
92         int i;
93
94         lib80211_crypt_quiescing(info);
95         del_timer_sync(&info->crypt_deinit_timer);
96         lib80211_crypt_deinit_entries(info, 1);
97
98         for (i = 0; i < NUM_WEP_KEYS; i++) {
99                 struct lib80211_crypt_data *crypt = info->crypt[i];
100                 if (crypt) {
101                         if (crypt->ops) {
102                                 crypt->ops->deinit(crypt->priv);
103                                 module_put(crypt->ops->owner);
104                         }
105                         kfree(crypt);
106                         info->crypt[i] = NULL;
107                 }
108         }
109 }
110 EXPORT_SYMBOL(lib80211_crypt_info_free);
111
112 void lib80211_crypt_deinit_entries(struct lib80211_crypt_info *info, int force)
113 {
114         struct lib80211_crypt_data *entry, *next;
115         unsigned long flags;
116
117         spin_lock_irqsave(info->lock, flags);
118         list_for_each_entry_safe(entry, next, &info->crypt_deinit_list, list) {
119                 if (atomic_read(&entry->refcnt) != 0 && !force)
120                         continue;
121
122                 list_del(&entry->list);
123
124                 if (entry->ops) {
125                         entry->ops->deinit(entry->priv);
126                         module_put(entry->ops->owner);
127                 }
128                 kfree(entry);
129         }
130         spin_unlock_irqrestore(info->lock, flags);
131 }
132 EXPORT_SYMBOL(lib80211_crypt_deinit_entries);
133
134 /* After this, crypt_deinit_list won't accept new members */
135 void lib80211_crypt_quiescing(struct lib80211_crypt_info *info)
136 {
137         unsigned long flags;
138
139         spin_lock_irqsave(info->lock, flags);
140         info->crypt_quiesced = 1;
141         spin_unlock_irqrestore(info->lock, flags);
142 }
143 EXPORT_SYMBOL(lib80211_crypt_quiescing);
144
145 void lib80211_crypt_deinit_handler(unsigned long data)
146 {
147         struct lib80211_crypt_info *info = (struct lib80211_crypt_info *)data;
148         unsigned long flags;
149
150         lib80211_crypt_deinit_entries(info, 0);
151
152         spin_lock_irqsave(info->lock, flags);
153         if (!list_empty(&info->crypt_deinit_list) && !info->crypt_quiesced) {
154                 printk(KERN_DEBUG "%s: entries remaining in delayed crypt "
155                        "deletion list\n", info->name);
156                 info->crypt_deinit_timer.expires = jiffies + HZ;
157                 add_timer(&info->crypt_deinit_timer);
158         }
159         spin_unlock_irqrestore(info->lock, flags);
160 }
161 EXPORT_SYMBOL(lib80211_crypt_deinit_handler);
162
163 void lib80211_crypt_delayed_deinit(struct lib80211_crypt_info *info,
164                                     struct lib80211_crypt_data **crypt)
165 {
166         struct lib80211_crypt_data *tmp;
167         unsigned long flags;
168
169         if (*crypt == NULL)
170                 return;
171
172         tmp = *crypt;
173         *crypt = NULL;
174
175         /* must not run ops->deinit() while there may be pending encrypt or
176          * decrypt operations. Use a list of delayed deinits to avoid needing
177          * locking. */
178
179         spin_lock_irqsave(info->lock, flags);
180         if (!info->crypt_quiesced) {
181                 list_add(&tmp->list, &info->crypt_deinit_list);
182                 if (!timer_pending(&info->crypt_deinit_timer)) {
183                         info->crypt_deinit_timer.expires = jiffies + HZ;
184                         add_timer(&info->crypt_deinit_timer);
185                 }
186         }
187         spin_unlock_irqrestore(info->lock, flags);
188 }
189 EXPORT_SYMBOL(lib80211_crypt_delayed_deinit);
190
191 int lib80211_register_crypto_ops(struct lib80211_crypto_ops *ops)
192 {
193         unsigned long flags;
194         struct lib80211_crypto_alg *alg;
195
196         alg = kzalloc(sizeof(*alg), GFP_KERNEL);
197         if (alg == NULL)
198                 return -ENOMEM;
199
200         alg->ops = ops;
201
202         spin_lock_irqsave(&lib80211_crypto_lock, flags);
203         list_add(&alg->list, &lib80211_crypto_algs);
204         spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
205
206         printk(KERN_DEBUG "lib80211_crypt: registered algorithm '%s'\n",
207                ops->name);
208
209         return 0;
210 }
211 EXPORT_SYMBOL(lib80211_register_crypto_ops);
212
213 int lib80211_unregister_crypto_ops(struct lib80211_crypto_ops *ops)
214 {
215         struct lib80211_crypto_alg *alg;
216         unsigned long flags;
217
218         spin_lock_irqsave(&lib80211_crypto_lock, flags);
219         list_for_each_entry(alg, &lib80211_crypto_algs, list) {
220                 if (alg->ops == ops)
221                         goto found;
222         }
223         spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
224         return -EINVAL;
225
226       found:
227         printk(KERN_DEBUG "lib80211_crypt: unregistered algorithm "
228                "'%s'\n", ops->name);
229         list_del(&alg->list);
230         spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
231         kfree(alg);
232         return 0;
233 }
234 EXPORT_SYMBOL(lib80211_unregister_crypto_ops);
235
236 struct lib80211_crypto_ops *lib80211_get_crypto_ops(const char *name)
237 {
238         struct lib80211_crypto_alg *alg;
239         unsigned long flags;
240
241         spin_lock_irqsave(&lib80211_crypto_lock, flags);
242         list_for_each_entry(alg, &lib80211_crypto_algs, list) {
243                 if (strcmp(alg->ops->name, name) == 0)
244                         goto found;
245         }
246         spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
247         return NULL;
248
249       found:
250         spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
251         return alg->ops;
252 }
253 EXPORT_SYMBOL(lib80211_get_crypto_ops);
254
255 static void *lib80211_crypt_null_init(int keyidx)
256 {
257         return (void *)1;
258 }
259
260 static void lib80211_crypt_null_deinit(void *priv)
261 {
262 }
263
264 static struct lib80211_crypto_ops lib80211_crypt_null = {
265         .name = "NULL",
266         .init = lib80211_crypt_null_init,
267         .deinit = lib80211_crypt_null_deinit,
268         .owner = THIS_MODULE,
269 };
270
271 static int __init lib80211_init(void)
272 {
273         printk(KERN_INFO DRV_NAME ": " DRV_DESCRIPTION "\n");
274         return lib80211_register_crypto_ops(&lib80211_crypt_null);
275 }
276
277 static void __exit lib80211_exit(void)
278 {
279         lib80211_unregister_crypto_ops(&lib80211_crypt_null);
280         BUG_ON(!list_empty(&lib80211_crypto_algs));
281 }
282
283 module_init(lib80211_init);
284 module_exit(lib80211_exit);