1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * lib80211 -- common bits for IEEE802.11 drivers |
4 | * |
5 | * Copyright(c) 2008 John W. Linville <linville@tuxdriver.com> |
6 | * |
7 | * Portions copied from old ieee80211 component, w/ original copyright |
8 | * notices below: |
9 | * |
10 | * Host AP crypto routines |
11 | * |
12 | * Copyright (c) 2002-2003, Jouni Malinen <j@w1.fi> |
13 | * Portions Copyright (C) 2004, Intel Corporation <jketreno@linux.intel.com> |
14 | * |
15 | */ |
16 | |
17 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
18 | |
19 | #include <linux/module.h> |
20 | #include <linux/ctype.h> |
21 | #include <linux/ieee80211.h> |
22 | #include <linux/errno.h> |
23 | #include <linux/init.h> |
24 | #include <linux/slab.h> |
25 | #include <linux/string.h> |
26 | |
27 | #include <net/lib80211.h> |
28 | |
29 | #define DRV_DESCRIPTION "common routines for IEEE802.11 drivers" |
30 | |
31 | MODULE_DESCRIPTION(DRV_DESCRIPTION); |
32 | MODULE_AUTHOR("John W. Linville <linville@tuxdriver.com>" ); |
33 | MODULE_LICENSE("GPL" ); |
34 | |
35 | struct lib80211_crypto_alg { |
36 | struct list_head list; |
37 | struct lib80211_crypto_ops *ops; |
38 | }; |
39 | |
40 | static LIST_HEAD(lib80211_crypto_algs); |
41 | static DEFINE_SPINLOCK(lib80211_crypto_lock); |
42 | |
43 | static void lib80211_crypt_deinit_entries(struct lib80211_crypt_info *info, |
44 | int force); |
45 | static void lib80211_crypt_quiescing(struct lib80211_crypt_info *info); |
46 | static void lib80211_crypt_deinit_handler(struct timer_list *t); |
47 | |
48 | int lib80211_crypt_info_init(struct lib80211_crypt_info *info, char *name, |
49 | spinlock_t *lock) |
50 | { |
51 | memset(info, 0, sizeof(*info)); |
52 | |
53 | info->name = name; |
54 | info->lock = lock; |
55 | |
56 | INIT_LIST_HEAD(list: &info->crypt_deinit_list); |
57 | timer_setup(&info->crypt_deinit_timer, lib80211_crypt_deinit_handler, |
58 | 0); |
59 | |
60 | return 0; |
61 | } |
62 | EXPORT_SYMBOL(lib80211_crypt_info_init); |
63 | |
64 | void lib80211_crypt_info_free(struct lib80211_crypt_info *info) |
65 | { |
66 | int i; |
67 | |
68 | lib80211_crypt_quiescing(info); |
69 | del_timer_sync(timer: &info->crypt_deinit_timer); |
70 | lib80211_crypt_deinit_entries(info, force: 1); |
71 | |
72 | for (i = 0; i < NUM_WEP_KEYS; i++) { |
73 | struct lib80211_crypt_data *crypt = info->crypt[i]; |
74 | if (crypt) { |
75 | if (crypt->ops) { |
76 | crypt->ops->deinit(crypt->priv); |
77 | module_put(module: crypt->ops->owner); |
78 | } |
79 | kfree(objp: crypt); |
80 | info->crypt[i] = NULL; |
81 | } |
82 | } |
83 | } |
84 | EXPORT_SYMBOL(lib80211_crypt_info_free); |
85 | |
86 | static void lib80211_crypt_deinit_entries(struct lib80211_crypt_info *info, |
87 | int force) |
88 | { |
89 | struct lib80211_crypt_data *entry, *next; |
90 | unsigned long flags; |
91 | |
92 | spin_lock_irqsave(info->lock, flags); |
93 | list_for_each_entry_safe(entry, next, &info->crypt_deinit_list, list) { |
94 | if (atomic_read(v: &entry->refcnt) != 0 && !force) |
95 | continue; |
96 | |
97 | list_del(entry: &entry->list); |
98 | |
99 | if (entry->ops) { |
100 | entry->ops->deinit(entry->priv); |
101 | module_put(module: entry->ops->owner); |
102 | } |
103 | kfree(objp: entry); |
104 | } |
105 | spin_unlock_irqrestore(lock: info->lock, flags); |
106 | } |
107 | |
108 | /* After this, crypt_deinit_list won't accept new members */ |
109 | static void lib80211_crypt_quiescing(struct lib80211_crypt_info *info) |
110 | { |
111 | unsigned long flags; |
112 | |
113 | spin_lock_irqsave(info->lock, flags); |
114 | info->crypt_quiesced = 1; |
115 | spin_unlock_irqrestore(lock: info->lock, flags); |
116 | } |
117 | |
118 | static void lib80211_crypt_deinit_handler(struct timer_list *t) |
119 | { |
120 | struct lib80211_crypt_info *info = from_timer(info, t, |
121 | crypt_deinit_timer); |
122 | unsigned long flags; |
123 | |
124 | lib80211_crypt_deinit_entries(info, force: 0); |
125 | |
126 | spin_lock_irqsave(info->lock, flags); |
127 | if (!list_empty(head: &info->crypt_deinit_list) && !info->crypt_quiesced) { |
128 | printk(KERN_DEBUG "%s: entries remaining in delayed crypt " |
129 | "deletion list\n" , info->name); |
130 | info->crypt_deinit_timer.expires = jiffies + HZ; |
131 | add_timer(timer: &info->crypt_deinit_timer); |
132 | } |
133 | spin_unlock_irqrestore(lock: info->lock, flags); |
134 | } |
135 | |
136 | void lib80211_crypt_delayed_deinit(struct lib80211_crypt_info *info, |
137 | struct lib80211_crypt_data **crypt) |
138 | { |
139 | struct lib80211_crypt_data *tmp; |
140 | unsigned long flags; |
141 | |
142 | if (*crypt == NULL) |
143 | return; |
144 | |
145 | tmp = *crypt; |
146 | *crypt = NULL; |
147 | |
148 | /* must not run ops->deinit() while there may be pending encrypt or |
149 | * decrypt operations. Use a list of delayed deinits to avoid needing |
150 | * locking. */ |
151 | |
152 | spin_lock_irqsave(info->lock, flags); |
153 | if (!info->crypt_quiesced) { |
154 | list_add(new: &tmp->list, head: &info->crypt_deinit_list); |
155 | if (!timer_pending(timer: &info->crypt_deinit_timer)) { |
156 | info->crypt_deinit_timer.expires = jiffies + HZ; |
157 | add_timer(timer: &info->crypt_deinit_timer); |
158 | } |
159 | } |
160 | spin_unlock_irqrestore(lock: info->lock, flags); |
161 | } |
162 | EXPORT_SYMBOL(lib80211_crypt_delayed_deinit); |
163 | |
164 | int lib80211_register_crypto_ops(struct lib80211_crypto_ops *ops) |
165 | { |
166 | unsigned long flags; |
167 | struct lib80211_crypto_alg *alg; |
168 | |
169 | alg = kzalloc(size: sizeof(*alg), GFP_KERNEL); |
170 | if (alg == NULL) |
171 | return -ENOMEM; |
172 | |
173 | alg->ops = ops; |
174 | |
175 | spin_lock_irqsave(&lib80211_crypto_lock, flags); |
176 | list_add(new: &alg->list, head: &lib80211_crypto_algs); |
177 | spin_unlock_irqrestore(lock: &lib80211_crypto_lock, flags); |
178 | |
179 | printk(KERN_DEBUG "lib80211_crypt: registered algorithm '%s'\n" , |
180 | ops->name); |
181 | |
182 | return 0; |
183 | } |
184 | EXPORT_SYMBOL(lib80211_register_crypto_ops); |
185 | |
186 | int lib80211_unregister_crypto_ops(struct lib80211_crypto_ops *ops) |
187 | { |
188 | struct lib80211_crypto_alg *alg; |
189 | unsigned long flags; |
190 | |
191 | spin_lock_irqsave(&lib80211_crypto_lock, flags); |
192 | list_for_each_entry(alg, &lib80211_crypto_algs, list) { |
193 | if (alg->ops == ops) |
194 | goto found; |
195 | } |
196 | spin_unlock_irqrestore(lock: &lib80211_crypto_lock, flags); |
197 | return -EINVAL; |
198 | |
199 | found: |
200 | printk(KERN_DEBUG "lib80211_crypt: unregistered algorithm '%s'\n" , |
201 | ops->name); |
202 | list_del(entry: &alg->list); |
203 | spin_unlock_irqrestore(lock: &lib80211_crypto_lock, flags); |
204 | kfree(objp: alg); |
205 | return 0; |
206 | } |
207 | EXPORT_SYMBOL(lib80211_unregister_crypto_ops); |
208 | |
209 | struct lib80211_crypto_ops *lib80211_get_crypto_ops(const char *name) |
210 | { |
211 | struct lib80211_crypto_alg *alg; |
212 | unsigned long flags; |
213 | |
214 | spin_lock_irqsave(&lib80211_crypto_lock, flags); |
215 | list_for_each_entry(alg, &lib80211_crypto_algs, list) { |
216 | if (strcmp(alg->ops->name, name) == 0) |
217 | goto found; |
218 | } |
219 | spin_unlock_irqrestore(lock: &lib80211_crypto_lock, flags); |
220 | return NULL; |
221 | |
222 | found: |
223 | spin_unlock_irqrestore(lock: &lib80211_crypto_lock, flags); |
224 | return alg->ops; |
225 | } |
226 | EXPORT_SYMBOL(lib80211_get_crypto_ops); |
227 | |
228 | static void *lib80211_crypt_null_init(int keyidx) |
229 | { |
230 | return (void *)1; |
231 | } |
232 | |
233 | static void lib80211_crypt_null_deinit(void *priv) |
234 | { |
235 | } |
236 | |
237 | static struct lib80211_crypto_ops lib80211_crypt_null = { |
238 | .name = "NULL" , |
239 | .init = lib80211_crypt_null_init, |
240 | .deinit = lib80211_crypt_null_deinit, |
241 | .owner = THIS_MODULE, |
242 | }; |
243 | |
244 | static int __init lib80211_init(void) |
245 | { |
246 | pr_info(DRV_DESCRIPTION "\n" ); |
247 | return lib80211_register_crypto_ops(&lib80211_crypt_null); |
248 | } |
249 | |
250 | static void __exit lib80211_exit(void) |
251 | { |
252 | lib80211_unregister_crypto_ops(&lib80211_crypt_null); |
253 | BUG_ON(!list_empty(&lib80211_crypto_algs)); |
254 | } |
255 | |
256 | module_init(lib80211_init); |
257 | module_exit(lib80211_exit); |
258 | |