drivers/staging/rtl8192e/rtllib_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 "rtllib.h"
  21
  22 struct rtllib_crypto_alg {
  23         struct list_head list;
  24         struct lib80211_crypto_ops *ops;
  25 };
  26
  27
  28 struct rtllib_crypto {
  29         struct list_head algs;
  30         spinlock_t lock;
  31 };
  32
  33 static struct rtllib_crypto *hcrypt;
  34
  35 void rtllib_crypt_deinit_entries(struct lib80211_crypt_info *info,
  36                                            int force)
  37 {
  38         struct list_head *ptr, *n;
  39         struct lib80211_crypt_data *entry;
  40
  41         for (ptr = info->crypt_deinit_list.next, n = ptr->next;
  42              ptr != &info->crypt_deinit_list; ptr = n, n = ptr->next) {
  43                 entry = list_entry(ptr, struct lib80211_crypt_data, list);
  44
  45                 if (atomic_read(&entry->refcnt) != 0 && !force)
  46                         continue;
  47
  48                 list_del(ptr);
  49
  50                 if (entry->ops)
  51                         entry->ops->deinit(entry->priv);
  52                 kfree(entry);
  53         }
  54 }
  55 EXPORT_SYMBOL(rtllib_crypt_deinit_entries);
  56
  57 void rtllib_crypt_deinit_handler(unsigned long data)
  58 {
  59         struct lib80211_crypt_info *info = (struct lib80211_crypt_info *)data;
  60         unsigned long flags;
  61
  62         spin_lock_irqsave(info->lock, flags);
  63         rtllib_crypt_deinit_entries(info, 0);
  64         if (!list_empty(&info->crypt_deinit_list)) {
  65                 printk(KERN_DEBUG "%s: entries remaining in delayed crypt "
  66                        "deletion list\n", info->name);
  67                 info->crypt_deinit_timer.expires = jiffies + HZ;
  68                 add_timer(&info->crypt_deinit_timer);
  69         }
  70         spin_unlock_irqrestore(info->lock, flags);
  71
  72 }
  73 EXPORT_SYMBOL(rtllib_crypt_deinit_handler);
  74
  75 void rtllib_crypt_delayed_deinit(struct lib80211_crypt_info *info,
  76                                  struct lib80211_crypt_data **crypt)
  77 {
  78         struct lib80211_crypt_data *tmp;
  79         unsigned long flags;
  80
  81         if (*crypt == NULL)
  82                 return;
  83
  84         tmp = *crypt;
  85         *crypt = NULL;
  86
  87         /* must not run ops->deinit() while there may be pending encrypt or
  88          * decrypt operations. Use a list of delayed deinits to avoid needing
  89          * locking. */
  90
  91         spin_lock_irqsave(info->lock, flags);
  92         list_add(&tmp->list, &info->crypt_deinit_list);
  93         if (!timer_pending(&info->crypt_deinit_timer)) {
  94                 info->crypt_deinit_timer.expires = jiffies + HZ;
  95                 add_timer(&info->crypt_deinit_timer);
  96         }
  97         spin_unlock_irqrestore(info->lock, flags);
  98 }
  99 EXPORT_SYMBOL(rtllib_crypt_delayed_deinit);
 100
 101 int rtllib_register_crypto_ops(struct lib80211_crypto_ops *ops)
 102 {
 103         unsigned long flags;
 104         struct rtllib_crypto_alg *alg;
 105
 106         if (hcrypt == NULL)
 107                 return -1;
 108
 109         alg = kzalloc(sizeof(*alg), GFP_KERNEL);
 110         if (alg == NULL)
 111                 return -ENOMEM;
 112
 113         alg->ops = ops;
 114
 115         spin_lock_irqsave(&hcrypt->lock, flags);
 116         list_add(&alg->list, &hcrypt->algs);
 117         spin_unlock_irqrestore(&hcrypt->lock, flags);
 118
 119         printk(KERN_DEBUG "rtllib_crypt: registered algorithm '%s'\n",
 120                ops->name);
 121
 122         return 0;
 123 }
 124 EXPORT_SYMBOL(rtllib_register_crypto_ops);
 125
 126 int rtllib_unregister_crypto_ops(struct lib80211_crypto_ops *ops)
 127 {
 128         unsigned long flags;
 129         struct list_head *ptr;
 130         struct rtllib_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 rtllib_crypto_alg *alg =
 138                         (struct rtllib_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                 printk(KERN_DEBUG "rtllib_crypt: unregistered algorithm "
 149                        "'%s'\n", ops->name);
 150                 kfree(del_alg);
 151         }
 152
 153         return del_alg ? 0 : -1;
 154 }
 155 EXPORT_SYMBOL(rtllib_unregister_crypto_ops);
 156
 157
 158 struct lib80211_crypto_ops *rtllib_get_crypto_ops(const char *name)
 159 {
 160         unsigned long flags;
 161         struct list_head *ptr;
 162         struct rtllib_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 rtllib_crypto_alg *alg =
 170                         (struct rtllib_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 EXPORT_SYMBOL(rtllib_get_crypto_ops);
 184
 185
 186 static void * rtllib_crypt_null_init(int keyidx) { return (void *) 1; }
 187 static void rtllib_crypt_null_deinit(void *priv) {}
 188
 189 static struct lib80211_crypto_ops rtllib_crypt_null = {
 190         .name                   = "NULL",
 191         .init                   = rtllib_crypt_null_init,
 192         .deinit                 = rtllib_crypt_null_deinit,
 193         .encrypt_mpdu           = NULL,
 194         .decrypt_mpdu           = NULL,
 195         .encrypt_msdu           = NULL,
 196         .decrypt_msdu           = NULL,
 197         .set_key                = NULL,
 198         .get_key                = NULL,
 199         .extra_mpdu_prefix_len  = 0,
 200         .extra_mpdu_postfix_len = 0,
 201         .extra_msdu_prefix_len  = 0,
 202         .extra_msdu_postfix_len = 0,
 203         .owner                  = THIS_MODULE,
 204 };
 205
 206
 207 int __init rtllib_crypto_init(void)
 208 {
 209         int ret = -ENOMEM;
 210
 211         hcrypt = kzalloc(sizeof(*hcrypt), GFP_KERNEL);
 212         if (!hcrypt)
 213                 goto out;
 214
 215         INIT_LIST_HEAD(&hcrypt->algs);
 216         spin_lock_init(&hcrypt->lock);
 217
 218         ret = lib80211_register_crypto_ops(&rtllib_crypt_null);
 219         if (ret < 0) {
 220                 kfree(hcrypt);
 221                 hcrypt = NULL;
 222         }
 223 out:
 224         return ret;
 225 }
 226
 227
 228 void __exit rtllib_crypto_deinit(void)
 229 {
 230         struct list_head *ptr, *n;
 231
 232         if (hcrypt == NULL)
 233                 return;
 234
 235         for (ptr = hcrypt->algs.next, n = ptr->next; ptr != &hcrypt->algs;
 236              ptr = n, n = ptr->next) {
 237                 struct rtllib_crypto_alg *alg =
 238                         (struct rtllib_crypto_alg *) ptr;
 239                 list_del(ptr);
 240                 printk(KERN_DEBUG "rtllib_crypt: unregistered algorithm "
 241                        "'%s' (deinit)\n", alg->ops->name);
 242                 kfree(alg);
 243         }
 244
 245         kfree(hcrypt);
 246 }
 247
 248 module_init(rtllib_crypto_init);
 249 module_exit(rtllib_crypto_deinit);
 250
 251 MODULE_LICENSE("GPL");