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);