drivers/net/wireless/hostap/hostap_crypt.c

   1 /*
   2  * Host AP crypto routines
   3  *
   4  * Copyright (c) 2002-2003, Jouni Malinen <jkmaline@cc.hut.fi>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation. See README and COPYING for
   9  * more details.
  10  */
  11
  12 struct hostap_crypto_alg {
  13         struct list_head list;
  14         struct hostap_crypto_ops *ops;
  15 };
  16
  17
  18 struct hostap_crypto {
  19         struct list_head algs;
  20         spinlock_t lock;
  21 };
  22
  23 static struct hostap_crypto *hcrypt;
  24
  25
  26 int hostap_register_crypto_ops(struct hostap_crypto_ops *ops)
  27 {
  28         unsigned long flags;
  29         struct hostap_crypto_alg *alg;
  30
  31         if (hcrypt == NULL)
  32                 return -1;
  33
  34         alg = (struct hostap_crypto_alg *) kmalloc(sizeof(*alg), GFP_KERNEL);
  35         if (alg == NULL)
  36                 return -ENOMEM;
  37
  38         memset(alg, 0, sizeof(*alg));
  39         alg->ops = ops;
  40
  41         spin_lock_irqsave(&hcrypt->lock, flags);
  42         list_add(&alg->list, &hcrypt->algs);
  43         spin_unlock_irqrestore(&hcrypt->lock, flags);
  44
  45         printk(KERN_DEBUG "hostap_crypt: registered algorithm '%s'\n",
  46                ops->name);
  47
  48         return 0;
  49 }
  50
  51
  52 int hostap_unregister_crypto_ops(struct hostap_crypto_ops *ops)
  53 {
  54         unsigned long flags;
  55         struct list_head *ptr;
  56         struct hostap_crypto_alg *del_alg = NULL;
  57
  58         if (hcrypt == NULL)
  59                 return -1;
  60
  61         spin_lock_irqsave(&hcrypt->lock, flags);
  62         for (ptr = hcrypt->algs.next; ptr != &hcrypt->algs; ptr = ptr->next) {
  63                 struct hostap_crypto_alg *alg =
  64                         (struct hostap_crypto_alg *) ptr;
  65                 if (alg->ops == ops) {
  66                         list_del(&alg->list);
  67                         del_alg = alg;
  68                         break;
  69                 }
  70         }
  71         spin_unlock_irqrestore(&hcrypt->lock, flags);
  72
  73         if (del_alg) {
  74                 printk(KERN_DEBUG "hostap_crypt: unregistered algorithm "
  75                        "'%s'\n", ops->name);
  76                 kfree(del_alg);
  77         }
  78
  79         return del_alg ? 0 : -1;
  80 }
  81
  82
  83 struct hostap_crypto_ops * hostap_get_crypto_ops(const char *name)
  84 {
  85         unsigned long flags;
  86         struct list_head *ptr;
  87         struct hostap_crypto_alg *found_alg = NULL;
  88
  89         if (hcrypt == NULL)
  90                 return NULL;
  91
  92         spin_lock_irqsave(&hcrypt->lock, flags);
  93         for (ptr = hcrypt->algs.next; ptr != &hcrypt->algs; ptr = ptr->next) {
  94                 struct hostap_crypto_alg *alg =
  95                         (struct hostap_crypto_alg *) ptr;
  96                 if (strcmp(alg->ops->name, name) == 0) {
  97                         found_alg = alg;
  98                         break;
  99                 }
 100         }
 101         spin_unlock_irqrestore(&hcrypt->lock, flags);
 102
 103         if (found_alg)
 104                 return found_alg->ops;
 105         else
 106                 return NULL;
 107 }
 108
 109
 110 static void * hostap_crypt_null_init(int keyidx) { return (void *) 1; }
 111 static void hostap_crypt_null_deinit(void *priv) {}
 112
 113 static struct hostap_crypto_ops hostap_crypt_null = {
 114         .name                   = "NULL",
 115         .init                   = hostap_crypt_null_init,
 116         .deinit                 = hostap_crypt_null_deinit,
 117         .encrypt_mpdu           = NULL,
 118         .decrypt_mpdu           = NULL,
 119         .encrypt_msdu           = NULL,
 120         .decrypt_msdu           = NULL,
 121         .set_key                = NULL,
 122         .get_key                = NULL,
 123         .extra_prefix_len       = 0,
 124         .extra_postfix_len      = 0
 125 };
 126
 127
 128 static int __init hostap_crypto_init(void)
 129 {
 130         hcrypt = (struct hostap_crypto *) kmalloc(sizeof(*hcrypt), GFP_KERNEL);
 131         if (hcrypt == NULL)
 132                 return -ENOMEM;
 133
 134         memset(hcrypt, 0, sizeof(*hcrypt));
 135         INIT_LIST_HEAD(&hcrypt->algs);
 136         spin_lock_init(&hcrypt->lock);
 137
 138         (void) hostap_register_crypto_ops(&hostap_crypt_null);
 139
 140         return 0;
 141 }
 142
 143
 144 static void __exit hostap_crypto_deinit(void)
 145 {
 146         struct list_head *ptr, *n;
 147
 148         if (hcrypt == NULL)
 149                 return;
 150
 151         for (ptr = hcrypt->algs.next, n = ptr->next; ptr != &hcrypt->algs;
 152              ptr = n, n = ptr->next) {
 153                 struct hostap_crypto_alg *alg =
 154                         (struct hostap_crypto_alg *) ptr;
 155                 list_del(ptr);
 156                 printk(KERN_DEBUG "hostap_crypt: unregistered algorithm "
 157                        "'%s' (deinit)\n", alg->ops->name);
 158                 kfree(alg);
 159         }
 160
 161         kfree(hcrypt);
 162 }
 163
 164
 165 EXPORT_SYMBOL(hostap_register_crypto_ops);
 166 EXPORT_SYMBOL(hostap_unregister_crypto_ops);
 167 EXPORT_SYMBOL(hostap_get_crypto_ops);