kernel/drivers/staging/rtl8192u/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/module.h>
  15 #include <linux/init.h>
  16 #include <linux/slab.h>
  17 #include <linux/string.h>
  18 #include <linux/errno.h>
  19
  20 #include "ieee80211.h"
  21
  22 MODULE_AUTHOR("Jouni Malinen");
  23 MODULE_DESCRIPTION("HostAP crypto");
  24 MODULE_LICENSE("GPL");
  25
  26 struct ieee80211_crypto_alg {
  27         struct list_head list;
  28         struct ieee80211_crypto_ops *ops;
  29 };
  30
  31
  32 struct ieee80211_crypto {
  33         struct list_head algs;
  34         spinlock_t lock;
  35 };
  36
  37 static struct ieee80211_crypto *hcrypt;
  38
  39 void ieee80211_crypt_deinit_entries(struct ieee80211_device *ieee,
  40                                            int force)
  41 {
  42         struct list_head *ptr, *n;
  43         struct ieee80211_crypt_data *entry;
  44
  45         for (ptr = ieee->crypt_deinit_list.next, n = ptr->next;
  46              ptr != &ieee->crypt_deinit_list; ptr = n, n = ptr->next) {
  47                 entry = list_entry(ptr, struct ieee80211_crypt_data, list);
  48
  49                 if (atomic_read(&entry->refcnt) != 0 && !force)
  50                         continue;
  51
  52                 list_del(ptr);
  53
  54                 if (entry->ops)
  55                         entry->ops->deinit(entry->priv);
  56                 kfree(entry);
  57         }
  58 }
  59
  60 void ieee80211_crypt_deinit_handler(unsigned long data)
  61 {
  62         struct ieee80211_device *ieee = (struct ieee80211_device *)data;
  63         unsigned long flags;
  64
  65         spin_lock_irqsave(&ieee->lock, flags);
  66         ieee80211_crypt_deinit_entries(ieee, 0);
  67         if (!list_empty(&ieee->crypt_deinit_list)) {
  68                 netdev_dbg(ieee->dev, "%s: entries remaining in delayed crypt deletion list\n",
  69                                 ieee->dev->name);
  70                 ieee->crypt_deinit_timer.expires = jiffies + HZ;
  71                 add_timer(&ieee->crypt_deinit_timer);
  72         }
  73         spin_unlock_irqrestore(&ieee->lock, flags);
  74
  75 }
  76
  77 void ieee80211_crypt_delayed_deinit(struct ieee80211_device *ieee,
  78                                     struct ieee80211_crypt_data **crypt)
  79 {
  80         struct ieee80211_crypt_data *tmp;
  81         unsigned long flags;
  82
  83         if (*crypt == NULL)
  84                 return;
  85
  86         tmp = *crypt;
  87         *crypt = NULL;
  88
  89         /* must not run ops->deinit() while there may be pending encrypt or
  90          * decrypt operations. Use a list of delayed deinits to avoid needing
  91          * locking. */
  92
  93         spin_lock_irqsave(&ieee->lock, flags);
  94         list_add(&tmp->list, &ieee->crypt_deinit_list);
  95         if (!timer_pending(&ieee->crypt_deinit_timer)) {
  96                 ieee->crypt_deinit_timer.expires = jiffies + HZ;
  97                 add_timer(&ieee->crypt_deinit_timer);
  98         }
  99         spin_unlock_irqrestore(&ieee->lock, flags);
 100 }
 101
 102 int ieee80211_register_crypto_ops(struct ieee80211_crypto_ops *ops)
 103 {
 104         unsigned long flags;
 105         struct ieee80211_crypto_alg *alg;
 106
 107         if (hcrypt == NULL)
 108                 return -1;
 109
 110         alg = kzalloc(sizeof(*alg), GFP_KERNEL);
 111         if (alg == NULL)
 112                 return -ENOMEM;
 113
 114         alg->ops = ops;
 115
 116         spin_lock_irqsave(&hcrypt->lock, flags);
 117         list_add(&alg->list, &hcrypt->algs);
 118         spin_unlock_irqrestore(&hcrypt->lock, flags);
 119
 120         pr_debug("ieee80211_crypt: registered algorithm '%s'\n",
 121                ops->name);
 122
 123         return 0;
 124 }
 125
 126 int ieee80211_unregister_crypto_ops(struct ieee80211_crypto_ops *ops)
 127 {
 128         unsigned long flags;
 129         struct list_head *ptr;
 130         struct ieee80211_crypto_alg *del_alg = NULL;
 131
 132         if (hcrypt == NULL)
 133                 return -1;
 134
 135         spin_lock_irqsave(&hcrypt->lock, flags);
 136         for (ptr = hcrypt->algs.next; ptr != &hcrypt->algs; ptr = ptr->next) {
 137                 struct ieee80211_crypto_alg *alg =
 138                         (struct ieee80211_crypto_alg *) ptr;
 139                 if (alg->ops == ops) {
 140                         list_del(&alg->list);
 141                         del_alg = alg;
 142                         break;
 143                 }
 144         }
 145         spin_unlock_irqrestore(&hcrypt->lock, flags);
 146
 147         if (del_alg) {
 148                 pr_debug("ieee80211_crypt: unregistered algorithm '%s'\n",
 149                                 ops->name);
 150                 kfree(del_alg);
 151         }
 152
 153         return del_alg ? 0 : -1;
 154 }
 155
 156
 157 struct ieee80211_crypto_ops *ieee80211_get_crypto_ops(const char *name)
 158 {
 159         unsigned long flags;
 160         struct list_head *ptr;
 161         struct ieee80211_crypto_alg *found_alg = NULL;
 162
 163         if (hcrypt == NULL)
 164                 return NULL;
 165
 166         spin_lock_irqsave(&hcrypt->lock, flags);
 167         for (ptr = hcrypt->algs.next; ptr != &hcrypt->algs; ptr = ptr->next) {
 168                 struct ieee80211_crypto_alg *alg =
 169                         (struct ieee80211_crypto_alg *) ptr;
 170                 if (strcmp(alg->ops->name, name) == 0) {
 171                         found_alg = alg;
 172                         break;
 173                 }
 174         }
 175         spin_unlock_irqrestore(&hcrypt->lock, flags);
 176
 177         if (found_alg)
 178                 return found_alg->ops;
 179         else
 180                 return NULL;
 181 }
 182
 183
 184 static void *ieee80211_crypt_null_init(int keyidx) { return (void *) 1; }
 185 static void ieee80211_crypt_null_deinit(void *priv) {}
 186
 187 static struct ieee80211_crypto_ops ieee80211_crypt_null = {
 188         .name                   = "NULL",
 189         .init                   = ieee80211_crypt_null_init,
 190         .deinit                 = ieee80211_crypt_null_deinit,
 191         .encrypt_mpdu           = NULL,
 192         .decrypt_mpdu           = NULL,
 193         .encrypt_msdu           = NULL,
 194         .decrypt_msdu           = NULL,
 195         .set_key                = NULL,
 196         .get_key                = NULL,
 197         .extra_prefix_len       = 0,
 198         .extra_postfix_len      = 0,
 199         .owner                  = THIS_MODULE,
 200 };
 201
 202 int __init ieee80211_crypto_init(void)
 203 {
 204         int ret = -ENOMEM;
 205
 206         hcrypt = kzalloc(sizeof(*hcrypt), GFP_KERNEL);
 207         if (!hcrypt)
 208                 goto out;
 209
 210         INIT_LIST_HEAD(&hcrypt->algs);
 211         spin_lock_init(&hcrypt->lock);
 212
 213         ret = ieee80211_register_crypto_ops(&ieee80211_crypt_null);
 214         if (ret < 0) {
 215                 kfree(hcrypt);
 216                 hcrypt = NULL;
 217         }
 218 out:
 219         return ret;
 220 }
 221
 222 void __exit ieee80211_crypto_deinit(void)
 223 {
 224         struct list_head *ptr, *n;
 225
 226         if (hcrypt == NULL)
 227                 return;
 228
 229         for (ptr = hcrypt->algs.next, n = ptr->next; ptr != &hcrypt->algs;
 230              ptr = n, n = ptr->next) {
 231                 struct ieee80211_crypto_alg *alg =
 232                         (struct ieee80211_crypto_alg *) ptr;
 233                 list_del(ptr);
 234                 pr_debug("ieee80211_crypt: unregistered algorithm '%s' (deinit)\n",
 235                                 alg->ops->name);
 236                 kfree(alg);
 237         }
 238
 239         kfree(hcrypt);
 240 }