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