release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/staging/rtl8192su/ieee80211/ieee80211_crypt.c

   1 /*
   2  * Host AP crypto routines
   3  *
   4  * Copyright (c) 2002-2003, Jouni Malinen <jkmaline@cc.hut.fi>
   5  * Portions Copyright (C) 2004, Intel Corporation <jketreno@linux.intel.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation. See README and COPYING for
  10  * more details.
  11  *
  12  */
  13
  14 #include <linux/version.h>
  15 #include <linux/module.h>
  16 #include <linux/init.h>
  17 #include <linux/slab.h>
  18 #include <asm/string.h>
  19 #include <asm/errno.h>
  20
  21 #include "ieee80211.h"
  22
  23 MODULE_AUTHOR("Jouni Malinen");
  24 MODULE_DESCRIPTION("HostAP crypto");
  25 MODULE_LICENSE("GPL");
  26
  27 struct ieee80211_crypto_alg {
  28         struct list_head list;
  29         struct ieee80211_crypto_ops *ops;
  30 };
  31
  32
  33 struct ieee80211_crypto {
  34         struct list_head algs;
  35         spinlock_t lock;
  36 };
  37
  38 static struct ieee80211_crypto *hcrypt;
  39
  40 void ieee80211_crypt_deinit_entries(struct ieee80211_device *ieee,
  41                                            int force)
  42 {
  43         struct list_head *ptr, *n;
  44         struct ieee80211_crypt_data *entry;
  45
  46         for (ptr = ieee->crypt_deinit_list.next, n = ptr->next;
  47              ptr != &ieee->crypt_deinit_list; ptr = n, n = ptr->next) {
  48                 entry = list_entry(ptr, struct ieee80211_crypt_data, list);
  49
  50                 if (atomic_read(&entry->refcnt) != 0 && !force)
  51                         continue;
  52
  53                 list_del(ptr);
  54
  55                 if (entry->ops)
  56                         entry->ops->deinit(entry->priv);
  57                 kfree(entry);
  58         }
  59 }
  60
  61 void ieee80211_crypt_deinit_handler(unsigned long data)
  62 {
  63         struct ieee80211_device *ieee = (struct ieee80211_device *)data;
  64         unsigned long flags;
  65
  66         spin_lock_irqsave(&ieee->lock, flags);
  67         ieee80211_crypt_deinit_entries(ieee, 0);
  68         if (!list_empty(&ieee->crypt_deinit_list)) {
  69                 printk(KERN_DEBUG "%s: entries remaining in delayed crypt "
  70                        "deletion list\n", ieee->dev->name);
  71                 ieee->crypt_deinit_timer.expires = jiffies + HZ;
  72                 add_timer(&ieee->crypt_deinit_timer);
  73         }
  74         spin_unlock_irqrestore(&ieee->lock, flags);
  75
  76 }
  77
  78 void ieee80211_crypt_delayed_deinit(struct ieee80211_device *ieee,
  79                                     struct ieee80211_crypt_data **crypt)
  80 {
  81         struct ieee80211_crypt_data *tmp;
  82         unsigned long flags;
  83
  84         if (*crypt == NULL)
  85                 return;
  86
  87         tmp = *crypt;
  88         *crypt = NULL;
  89
  90         /* must not run ops->deinit() while there may be pending encrypt or
  91          * decrypt operations. Use a list of delayed deinits to avoid needing
  92          * locking. */
  93
  94         spin_lock_irqsave(&ieee->lock, flags);
  95         list_add(&tmp->list, &ieee->crypt_deinit_list);
  96         if (!timer_pending(&ieee->crypt_deinit_timer)) {
  97                 ieee->crypt_deinit_timer.expires = jiffies + HZ;
  98                 add_timer(&ieee->crypt_deinit_timer);
  99         }
 100         spin_unlock_irqrestore(&ieee->lock, flags);
 101 }
 102
 103 int ieee80211_register_crypto_ops(struct ieee80211_crypto_ops *ops)
 104 {
 105         unsigned long flags;
 106         struct ieee80211_crypto_alg *alg;
 107
 108         if (hcrypt == NULL)
 109                 return -1;
 110
 111         alg = kzalloc(sizeof(*alg), GFP_KERNEL);
 112         if (alg == NULL)
 113                 return -ENOMEM;
 114
 115         alg->ops = ops;
 116
 117         spin_lock_irqsave(&hcrypt->lock, flags);
 118         list_add(&alg->list, &hcrypt->algs);
 119         spin_unlock_irqrestore(&hcrypt->lock, flags);
 120
 121         printk(KERN_DEBUG "ieee80211_crypt: registered algorithm '%s'\n",
 122                ops->name);
 123
 124         return 0;
 125 }
 126
 127 int ieee80211_unregister_crypto_ops(struct ieee80211_crypto_ops *ops)
 128 {
 129         unsigned long flags;
 130         struct list_head *ptr;
 131         struct ieee80211_crypto_alg *del_alg = NULL;
 132
 133         if (hcrypt == NULL)
 134                 return -1;
 135
 136         spin_lock_irqsave(&hcrypt->lock, flags);
 137         for (ptr = hcrypt->algs.next; ptr != &hcrypt->algs; ptr = ptr->next) {
 138                 struct ieee80211_crypto_alg *alg =
 139                         (struct ieee80211_crypto_alg *) ptr;
 140                 if (alg->ops == ops) {
 141                         list_del(&alg->list);
 142                         del_alg = alg;
 143                         break;
 144                 }
 145         }
 146         spin_unlock_irqrestore(&hcrypt->lock, flags);
 147
 148         if (del_alg) {
 149                 printk(KERN_DEBUG "ieee80211_crypt: unregistered algorithm "
 150                        "'%s'\n", ops->name);
 151                 kfree(del_alg);
 152         }
 153
 154         return del_alg ? 0 : -1;
 155 }
 156
 157
 158 struct ieee80211_crypto_ops * ieee80211_get_crypto_ops(const char *name)
 159 {
 160         unsigned long flags;
 161         struct list_head *ptr;
 162         struct ieee80211_crypto_alg *found_alg = NULL;
 163
 164         if (hcrypt == NULL)
 165                 return NULL;
 166
 167         spin_lock_irqsave(&hcrypt->lock, flags);
 168         for (ptr = hcrypt->algs.next; ptr != &hcrypt->algs; ptr = ptr->next) {
 169                 struct ieee80211_crypto_alg *alg =
 170                         (struct ieee80211_crypto_alg *) ptr;
 171                 if (strcmp(alg->ops->name, name) == 0) {
 172                         found_alg = alg;
 173                         break;
 174                 }
 175         }
 176         spin_unlock_irqrestore(&hcrypt->lock, flags);
 177
 178         if (found_alg)
 179                 return found_alg->ops;
 180         else
 181                 return NULL;
 182 }
 183
 184
 185 static void * ieee80211_crypt_null_init(int keyidx) { return (void *) 1; }
 186 static void ieee80211_crypt_null_deinit(void *priv) {}
 187
 188 static struct ieee80211_crypto_ops ieee80211_crypt_null = {
 189         .name                   = "NULL",
 190         .init                   = ieee80211_crypt_null_init,
 191         .deinit                 = ieee80211_crypt_null_deinit,
 192         .encrypt_mpdu           = NULL,
 193         .decrypt_mpdu           = NULL,
 194         .encrypt_msdu           = NULL,
 195         .decrypt_msdu           = NULL,
 196         .set_key                = NULL,
 197         .get_key                = NULL,
 198         .extra_prefix_len       = 0,
 199         .extra_postfix_len      = 0,
 200         .owner                  = THIS_MODULE,
 201 };
 202
 203 int ieee80211_crypto_init(void)
 204 {
 205         int ret = -ENOMEM;
 206
 207         hcrypt = kzalloc(sizeof(*hcrypt), GFP_KERNEL);
 208         if (!hcrypt)
 209                 goto out;
 210
 211         INIT_LIST_HEAD(&hcrypt->algs);
 212         spin_lock_init(&hcrypt->lock);
 213
 214         ret = ieee80211_register_crypto_ops(&ieee80211_crypt_null);
 215         if (ret < 0) {
 216                 kfree(hcrypt);
 217                 hcrypt = NULL;
 218         }
 219 out:
 220         return ret;
 221 }
 222
 223 void ieee80211_crypto_deinit(void)
 224 {
 225         struct list_head *ptr, *n;
 226         struct ieee80211_crypto_alg *alg = NULL;
 227
 228         if (hcrypt == NULL)
 229                 return;
 230
 231         list_for_each_safe(ptr, n, &hcrypt->algs) {
 232                 alg = list_entry(ptr, struct ieee80211_crypto_alg, list);
 233                 if (alg) {
 234                         list_del(ptr);
 235                         printk(KERN_DEBUG
 236                                "ieee80211_crypt: unregistered algorithm '%s' (deinit)\n",
 237                                alg->ops->name);
 238                         kfree(alg);
 239                 }
 240         }
 241         kfree(hcrypt);
 242 }