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/config.h>
  15 #include <linux/version.h>
  16 #include <linux/module.h>
  17 #include <linux/init.h>
  18 #include <linux/slab.h>
  19 #include <asm/string.h>
  20 #include <asm/errno.h>
  21
  22 #include "ieee80211.h"
  23
  24 MODULE_AUTHOR("Jouni Malinen");
  25 MODULE_DESCRIPTION("HostAP crypto");
  26 MODULE_LICENSE("GPL");
  27
  28 struct ieee80211_crypto_alg {
  29         struct list_head list;
  30         struct ieee80211_crypto_ops *ops;
  31 };
  32
  33
  34 struct ieee80211_crypto {
  35         struct list_head algs;
  36         spinlock_t lock;
  37 };
  38
  39 static struct ieee80211_crypto *hcrypt;
  40
  41 void ieee80211_crypt_deinit_entries(struct ieee80211_device *ieee,
  42                                            int force)
  43 {
  44         struct list_head *ptr, *n;
  45         struct ieee80211_crypt_data *entry;
  46
  47         for (ptr = ieee->crypt_deinit_list.next, n = ptr->next;
  48              ptr != &ieee->crypt_deinit_list; ptr = n, n = ptr->next) {
  49                 entry = list_entry(ptr, struct ieee80211_crypt_data, list);
  50
  51                 if (atomic_read(&entry->refcnt) != 0 && !force)
  52                         continue;
  53
  54                 list_del(ptr);
  55
  56                 if (entry->ops)
  57                         entry->ops->deinit(entry->priv);
  58                 kfree(entry);
  59         }
  60 }
  61
  62 void ieee80211_crypt_deinit_handler(unsigned long data)
  63 {
  64         struct ieee80211_device *ieee = (struct ieee80211_device *)data;
  65         unsigned long flags;
  66
  67         spin_lock_irqsave(&ieee->lock, flags);
  68         ieee80211_crypt_deinit_entries(ieee, 0);
  69         if (!list_empty(&ieee->crypt_deinit_list)) {
  70                 printk(KERN_DEBUG "%s: entries remaining in delayed crypt "
  71                        "deletion list\n", ieee->dev->name);
  72                 ieee->crypt_deinit_timer.expires = jiffies + HZ;
  73                 add_timer(&ieee->crypt_deinit_timer);
  74         }
  75         spin_unlock_irqrestore(&ieee->lock, flags);
  76
  77 }
  78
  79 void ieee80211_crypt_delayed_deinit(struct ieee80211_device *ieee,
  80                                     struct ieee80211_crypt_data **crypt)
  81 {
  82         struct ieee80211_crypt_data *tmp;
  83         unsigned long flags;
  84
  85         if (*crypt == NULL)
  86                 return;
  87
  88         tmp = *crypt;
  89         *crypt = NULL;
  90
  91         /* must not run ops->deinit() while there may be pending encrypt or
  92          * decrypt operations. Use a list of delayed deinits to avoid needing
  93          * locking. */
  94
  95         spin_lock_irqsave(&ieee->lock, flags);
  96         list_add(&tmp->list, &ieee->crypt_deinit_list);
  97         if (!timer_pending(&ieee->crypt_deinit_timer)) {
  98                 ieee->crypt_deinit_timer.expires = jiffies + HZ;
  99                 add_timer(&ieee->crypt_deinit_timer);
 100         }
 101         spin_unlock_irqrestore(&ieee->lock, flags);
 102 }
 103
 104 int ieee80211_register_crypto_ops(struct ieee80211_crypto_ops *ops)
 105 {
 106         unsigned long flags;
 107         struct ieee80211_crypto_alg *alg;
 108
 109         if (hcrypt == NULL)
 110                 return -1;
 111
 112         alg = kmalloc(sizeof(*alg), GFP_KERNEL);
 113         if (alg == NULL)
 114                 return -ENOMEM;
 115
 116         memset(alg, 0, sizeof(*alg));
 117         alg->ops = ops;
 118
 119         spin_lock_irqsave(&hcrypt->lock, flags);
 120         list_add(&alg->list, &hcrypt->algs);
 121         spin_unlock_irqrestore(&hcrypt->lock, flags);
 122
 123         printk(KERN_DEBUG "ieee80211_crypt: registered algorithm '%s'\n",
 124                ops->name);
 125
 126         return 0;
 127 }
 128
 129 int ieee80211_unregister_crypto_ops(struct ieee80211_crypto_ops *ops)
 130 {
 131         unsigned long flags;
 132         struct list_head *ptr;
 133         struct ieee80211_crypto_alg *del_alg = NULL;
 134
 135         if (hcrypt == NULL)
 136                 return -1;
 137
 138         spin_lock_irqsave(&hcrypt->lock, flags);
 139         for (ptr = hcrypt->algs.next; ptr != &hcrypt->algs; ptr = ptr->next) {
 140                 struct ieee80211_crypto_alg *alg =
 141                         (struct ieee80211_crypto_alg *) ptr;
 142                 if (alg->ops == ops) {
 143                         list_del(&alg->list);
 144                         del_alg = alg;
 145                         break;
 146                 }
 147         }
 148         spin_unlock_irqrestore(&hcrypt->lock, flags);
 149
 150         if (del_alg) {
 151                 printk(KERN_DEBUG "ieee80211_crypt: unregistered algorithm "
 152                        "'%s'\n", ops->name);
 153                 kfree(del_alg);
 154         }
 155
 156         return del_alg ? 0 : -1;
 157 }
 158
 159
 160 struct ieee80211_crypto_ops * ieee80211_get_crypto_ops(const char *name)
 161 {
 162         unsigned long flags;
 163         struct list_head *ptr;
 164         struct ieee80211_crypto_alg *found_alg = NULL;
 165
 166         if (hcrypt == NULL)
 167                 return NULL;
 168
 169         spin_lock_irqsave(&hcrypt->lock, flags);
 170         for (ptr = hcrypt->algs.next; ptr != &hcrypt->algs; ptr = ptr->next) {
 171                 struct ieee80211_crypto_alg *alg =
 172                         (struct ieee80211_crypto_alg *) ptr;
 173                 if (strcmp(alg->ops->name, name) == 0) {
 174                         found_alg = alg;
 175                         break;
 176                 }
 177         }
 178         spin_unlock_irqrestore(&hcrypt->lock, flags);
 179
 180         if (found_alg)
 181                 return found_alg->ops;
 182         else
 183                 return NULL;
 184 }
 185
 186
 187 static void * ieee80211_crypt_null_init(int keyidx) { return (void *) 1; }
 188 static void ieee80211_crypt_null_deinit(void *priv) {}
 189
 190 static struct ieee80211_crypto_ops ieee80211_crypt_null = {
 191         .name                   = "NULL",
 192         .init                   = ieee80211_crypt_null_init,
 193         .deinit                 = ieee80211_crypt_null_deinit,
 194         .encrypt_mpdu           = NULL,
 195         .decrypt_mpdu           = NULL,
 196         .encrypt_msdu           = NULL,
 197         .decrypt_msdu           = NULL,
 198         .set_key                = NULL,
 199         .get_key                = NULL,
 200         .extra_prefix_len       = 0,
 201         .extra_postfix_len      = 0,
 202         .owner                  = THIS_MODULE,
 203 };
 204
 205 int __init ieee80211_crypto_init(void)
 206 {
 207         int ret = -ENOMEM;
 208
 209         hcrypt = kmalloc(sizeof(*hcrypt), GFP_KERNEL);
 210         if (!hcrypt)
 211                 goto out;
 212
 213         memset(hcrypt, 0, sizeof(*hcrypt));
 214         INIT_LIST_HEAD(&hcrypt->algs);
 215         spin_lock_init(&hcrypt->lock);
 216
 217         ret = ieee80211_register_crypto_ops(&ieee80211_crypt_null);
 218         if (ret < 0) {
 219                 kfree(hcrypt);
 220                 hcrypt = NULL;
 221         }
 222 out:
 223         return ret;
 224 }
 225
 226 void __exit ieee80211_crypto_deinit(void)
 227 {
 228         struct list_head *ptr, *n;
 229
 230         if (hcrypt == NULL)
 231                 return;
 232
 233         for (ptr = hcrypt->algs.next, n = ptr->next; ptr != &hcrypt->algs;
 234              ptr = n, n = ptr->next) {
 235                 struct ieee80211_crypto_alg *alg =
 236                         (struct ieee80211_crypto_alg *) ptr;
 237                 list_del(ptr);
 238                 printk(KERN_DEBUG "ieee80211_crypt: unregistered algorithm "
 239                        "'%s' (deinit)\n", alg->ops->name);
 240                 kfree(alg);
 241         }
 242
 243         kfree(hcrypt);
 244 }