xref: /openbmc/linux/net/wireless/lib80211.c (revision b6dcefde)
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);
285