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 void lib80211_crypt_deinit_entries(struct lib80211_crypt_info *info, int force)
  75 {
  76         struct lib80211_crypt_data *entry, *next;
  77         unsigned long flags;
  78
  79         spin_lock_irqsave(info->lock, flags);
  80         list_for_each_entry_safe(entry, next, &info->crypt_deinit_list, list) {
  81                 if (atomic_read(&entry->refcnt) != 0 && !force)
  82                         continue;
  83
  84                 list_del(&entry->list);
  85
  86                 if (entry->ops) {
  87                         entry->ops->deinit(entry->priv);
  88                         module_put(entry->ops->owner);
  89                 }
  90                 kfree(entry);
  91         }
  92         spin_unlock_irqrestore(info->lock, flags);
  93 }
  94 EXPORT_SYMBOL(lib80211_crypt_deinit_entries);
  95
  96 /* After this, crypt_deinit_list won't accept new members */
  97 void lib80211_crypt_quiescing(struct lib80211_crypt_info *info)
  98 {
  99         unsigned long flags;
 100
 101         spin_lock_irqsave(info->lock, flags);
 102         info->crypt_quiesced = 1;
 103         spin_unlock_irqrestore(info->lock, flags);
 104 }
 105 EXPORT_SYMBOL(lib80211_crypt_quiescing);
 106
 107 void lib80211_crypt_deinit_handler(unsigned long data)
 108 {
 109         struct lib80211_crypt_info *info = (struct lib80211_crypt_info *)data;
 110         unsigned long flags;
 111
 112         lib80211_crypt_deinit_entries(info, 0);
 113
 114         spin_lock_irqsave(info->lock, flags);
 115         if (!list_empty(&info->crypt_deinit_list) && !info->crypt_quiesced) {
 116                 printk(KERN_DEBUG "%s: entries remaining in delayed crypt "
 117                        "deletion list\n", info->name);
 118                 info->crypt_deinit_timer.expires = jiffies + HZ;
 119                 add_timer(&info->crypt_deinit_timer);
 120         }
 121         spin_unlock_irqrestore(info->lock, flags);
 122 }
 123 EXPORT_SYMBOL(lib80211_crypt_deinit_handler);
 124
 125 void lib80211_crypt_delayed_deinit(struct lib80211_crypt_info *info,
 126                                     struct lib80211_crypt_data **crypt)
 127 {
 128         struct lib80211_crypt_data *tmp;
 129         unsigned long flags;
 130
 131         if (*crypt == NULL)
 132                 return;
 133
 134         tmp = *crypt;
 135         *crypt = NULL;
 136
 137         /* must not run ops->deinit() while there may be pending encrypt or
 138          * decrypt operations. Use a list of delayed deinits to avoid needing
 139          * locking. */
 140
 141         spin_lock_irqsave(info->lock, flags);
 142         if (!info->crypt_quiesced) {
 143                 list_add(&tmp->list, &info->crypt_deinit_list);
 144                 if (!timer_pending(&info->crypt_deinit_timer)) {
 145                         info->crypt_deinit_timer.expires = jiffies + HZ;
 146                         add_timer(&info->crypt_deinit_timer);
 147                 }
 148         }
 149         spin_unlock_irqrestore(info->lock, flags);
 150 }
 151 EXPORT_SYMBOL(lib80211_crypt_delayed_deinit);
 152
 153 int lib80211_register_crypto_ops(struct lib80211_crypto_ops *ops)
 154 {
 155         unsigned long flags;
 156         struct lib80211_crypto_alg *alg;
 157
 158         alg = kzalloc(sizeof(*alg), GFP_KERNEL);
 159         if (alg == NULL)
 160                 return -ENOMEM;
 161
 162         alg->ops = ops;
 163
 164         spin_lock_irqsave(&lib80211_crypto_lock, flags);
 165         list_add(&alg->list, &lib80211_crypto_algs);
 166         spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
 167
 168         printk(KERN_DEBUG "lib80211_crypt: registered algorithm '%s'\n",
 169                ops->name);
 170
 171         return 0;
 172 }
 173 EXPORT_SYMBOL(lib80211_register_crypto_ops);
 174
 175 int lib80211_unregister_crypto_ops(struct lib80211_crypto_ops *ops)
 176 {
 177         struct lib80211_crypto_alg *alg;
 178         unsigned long flags;
 179
 180         spin_lock_irqsave(&lib80211_crypto_lock, flags);
 181         list_for_each_entry(alg, &lib80211_crypto_algs, list) {
 182                 if (alg->ops == ops)
 183                         goto found;
 184         }
 185         spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
 186         return -EINVAL;
 187
 188       found:
 189         printk(KERN_DEBUG "lib80211_crypt: unregistered algorithm "
 190                "'%s'\n", ops->name);
 191         list_del(&alg->list);
 192         spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
 193         kfree(alg);
 194         return 0;
 195 }
 196 EXPORT_SYMBOL(lib80211_unregister_crypto_ops);
 197
 198 struct lib80211_crypto_ops *lib80211_get_crypto_ops(const char *name)
 199 {
 200         struct lib80211_crypto_alg *alg;
 201         unsigned long flags;
 202
 203         spin_lock_irqsave(&lib80211_crypto_lock, flags);
 204         list_for_each_entry(alg, &lib80211_crypto_algs, list) {
 205                 if (strcmp(alg->ops->name, name) == 0)
 206                         goto found;
 207         }
 208         spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
 209         return NULL;
 210
 211       found:
 212         spin_unlock_irqrestore(&lib80211_crypto_lock, flags);
 213         return alg->ops;
 214 }
 215 EXPORT_SYMBOL(lib80211_get_crypto_ops);
 216
 217 static void *lib80211_crypt_null_init(int keyidx)
 218 {
 219         return (void *)1;
 220 }
 221
 222 static void lib80211_crypt_null_deinit(void *priv)
 223 {
 224 }
 225
 226 static struct lib80211_crypto_ops lib80211_crypt_null = {
 227         .name = "NULL",
 228         .init = lib80211_crypt_null_init,
 229         .deinit = lib80211_crypt_null_deinit,
 230         .owner = THIS_MODULE,
 231 };
 232
 233 static int __init lib80211_init(void)
 234 {
 235         printk(KERN_INFO DRV_NAME ": " DRV_DESCRIPTION "\n");
 236         return lib80211_register_crypto_ops(&lib80211_crypt_null);
 237 }
 238
 239 static void __exit lib80211_exit(void)
 240 {
 241         lib80211_unregister_crypto_ops(&lib80211_crypt_null);
 242         BUG_ON(!list_empty(&lib80211_crypto_algs));
 243 }
 244
 245 module_init(lib80211_init);
 246 module_exit(lib80211_exit);