drivers/net/wireless/intel/ipw2x00/libipw_crypto.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * libipw -- common bits for IPW drivers
   4  *
   5  * Copyright(c) 2008 John W. Linville <linville@tuxdriver.com>
   6  *
   7  * Portions copied from old ieee80211 component, w/ original copyright
   8  * notices below:
   9  *
  10  * Host AP crypto routines
  11  *
  12  * Copyright (c) 2002-2003, Jouni Malinen <j@w1.fi>
  13  * Portions Copyright (C) 2004, Intel Corporation <jketreno@linux.intel.com>
  14  *
  15  */
  16
  17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  18
  19 #include <linux/module.h>
  20 #include <linux/ctype.h>
  21 #include <linux/ieee80211.h>
  22 #include <linux/errno.h>
  23 #include <linux/init.h>
  24 #include <linux/slab.h>
  25 #include <linux/string.h>
  26 #include "libipw.h"
  27
  28 struct libipw_crypto_alg {
  29         struct list_head list;
  30         const struct libipw_crypto_ops *ops;
  31 };
  32
  33 static LIST_HEAD(libipw_crypto_algs);
  34 static DEFINE_SPINLOCK(libipw_crypto_lock);
  35
  36 static void libipw_crypt_deinit_entries(struct libipw_crypt_info *info,
  37                                           int force);
  38 static void libipw_crypt_quiescing(struct libipw_crypt_info *info);
  39 static void libipw_crypt_deinit_handler(struct timer_list *t);
  40
  41 int libipw_crypt_info_init(struct libipw_crypt_info *info, char *name,
  42                                 spinlock_t *lock)
  43 {
  44         memset(info, 0, sizeof(*info));
  45
  46         info->name = name;
  47         info->lock = lock;
  48
  49         INIT_LIST_HEAD(&info->crypt_deinit_list);
  50         timer_setup(&info->crypt_deinit_timer, libipw_crypt_deinit_handler,
  51                     0);
  52
  53         return 0;
  54 }
  55 EXPORT_SYMBOL(libipw_crypt_info_init);
  56
  57 void libipw_crypt_info_free(struct libipw_crypt_info *info)
  58 {
  59         int i;
  60
  61         libipw_crypt_quiescing(info);
  62         del_timer_sync(&info->crypt_deinit_timer);
  63         libipw_crypt_deinit_entries(info, 1);
  64
  65         for (i = 0; i < NUM_WEP_KEYS; i++) {
  66                 struct libipw_crypt_data *crypt = info->crypt[i];
  67                 if (crypt) {
  68                         if (crypt->ops) {
  69                                 crypt->ops->deinit(crypt->priv);
  70                                 module_put(crypt->ops->owner);
  71                         }
  72                         kfree(crypt);
  73                         info->crypt[i] = NULL;
  74                 }
  75         }
  76 }
  77 EXPORT_SYMBOL(libipw_crypt_info_free);
  78
  79 static void libipw_crypt_deinit_entries(struct libipw_crypt_info *info,
  80                                         int force)
  81 {
  82         struct libipw_crypt_data *entry, *next;
  83         unsigned long flags;
  84
  85         spin_lock_irqsave(info->lock, flags);
  86         list_for_each_entry_safe(entry, next, &info->crypt_deinit_list, list) {
  87                 if (atomic_read(&entry->refcnt) != 0 && !force)
  88                         continue;
  89
  90                 list_del(&entry->list);
  91
  92                 if (entry->ops) {
  93                         entry->ops->deinit(entry->priv);
  94                         module_put(entry->ops->owner);
  95                 }
  96                 kfree(entry);
  97         }
  98         spin_unlock_irqrestore(info->lock, flags);
  99 }
 100
 101 /* After this, crypt_deinit_list won't accept new members */
 102 static void libipw_crypt_quiescing(struct libipw_crypt_info *info)
 103 {
 104         unsigned long flags;
 105
 106         spin_lock_irqsave(info->lock, flags);
 107         info->crypt_quiesced = 1;
 108         spin_unlock_irqrestore(info->lock, flags);
 109 }
 110
 111 static void libipw_crypt_deinit_handler(struct timer_list *t)
 112 {
 113         struct libipw_crypt_info *info = from_timer(info, t,
 114                                                     crypt_deinit_timer);
 115         unsigned long flags;
 116
 117         libipw_crypt_deinit_entries(info, 0);
 118
 119         spin_lock_irqsave(info->lock, flags);
 120         if (!list_empty(&info->crypt_deinit_list) && !info->crypt_quiesced) {
 121                 printk(KERN_DEBUG "%s: entries remaining in delayed crypt "
 122                        "deletion list\n", info->name);
 123                 info->crypt_deinit_timer.expires = jiffies + HZ;
 124                 add_timer(&info->crypt_deinit_timer);
 125         }
 126         spin_unlock_irqrestore(info->lock, flags);
 127 }
 128
 129 void libipw_crypt_delayed_deinit(struct libipw_crypt_info *info,
 130                                  struct libipw_crypt_data **crypt)
 131 {
 132         struct libipw_crypt_data *tmp;
 133         unsigned long flags;
 134
 135         if (*crypt == NULL)
 136                 return;
 137
 138         tmp = *crypt;
 139         *crypt = NULL;
 140
 141         /* must not run ops->deinit() while there may be pending encrypt or
 142          * decrypt operations. Use a list of delayed deinits to avoid needing
 143          * locking. */
 144
 145         spin_lock_irqsave(info->lock, flags);
 146         if (!info->crypt_quiesced) {
 147                 list_add(&tmp->list, &info->crypt_deinit_list);
 148                 if (!timer_pending(&info->crypt_deinit_timer)) {
 149                         info->crypt_deinit_timer.expires = jiffies + HZ;
 150                         add_timer(&info->crypt_deinit_timer);
 151                 }
 152         }
 153         spin_unlock_irqrestore(info->lock, flags);
 154 }
 155 EXPORT_SYMBOL(libipw_crypt_delayed_deinit);
 156
 157 int libipw_register_crypto_ops(const struct libipw_crypto_ops *ops)
 158 {
 159         unsigned long flags;
 160         struct libipw_crypto_alg *alg;
 161
 162         alg = kzalloc(sizeof(*alg), GFP_KERNEL);
 163         if (alg == NULL)
 164                 return -ENOMEM;
 165
 166         alg->ops = ops;
 167
 168         spin_lock_irqsave(&libipw_crypto_lock, flags);
 169         list_add(&alg->list, &libipw_crypto_algs);
 170         spin_unlock_irqrestore(&libipw_crypto_lock, flags);
 171
 172         printk(KERN_DEBUG "libipw_crypt: registered algorithm '%s'\n",
 173                ops->name);
 174
 175         return 0;
 176 }
 177 EXPORT_SYMBOL(libipw_register_crypto_ops);
 178
 179 int libipw_unregister_crypto_ops(const struct libipw_crypto_ops *ops)
 180 {
 181         struct libipw_crypto_alg *alg;
 182         unsigned long flags;
 183
 184         spin_lock_irqsave(&libipw_crypto_lock, flags);
 185         list_for_each_entry(alg, &libipw_crypto_algs, list) {
 186                 if (alg->ops == ops)
 187                         goto found;
 188         }
 189         spin_unlock_irqrestore(&libipw_crypto_lock, flags);
 190         return -EINVAL;
 191
 192       found:
 193         printk(KERN_DEBUG "libipw_crypt: unregistered algorithm '%s'\n",
 194                ops->name);
 195         list_del(&alg->list);
 196         spin_unlock_irqrestore(&libipw_crypto_lock, flags);
 197         kfree(alg);
 198         return 0;
 199 }
 200 EXPORT_SYMBOL(libipw_unregister_crypto_ops);
 201
 202 const struct libipw_crypto_ops *libipw_get_crypto_ops(const char *name)
 203 {
 204         struct libipw_crypto_alg *alg;
 205         unsigned long flags;
 206
 207         spin_lock_irqsave(&libipw_crypto_lock, flags);
 208         list_for_each_entry(alg, &libipw_crypto_algs, list) {
 209                 if (strcmp(alg->ops->name, name) == 0)
 210                         goto found;
 211         }
 212         spin_unlock_irqrestore(&libipw_crypto_lock, flags);
 213         return NULL;
 214
 215       found:
 216         spin_unlock_irqrestore(&libipw_crypto_lock, flags);
 217         return alg->ops;
 218 }
 219 EXPORT_SYMBOL(libipw_get_crypto_ops);
 220
 221 static void *libipw_crypt_null_init(int keyidx)
 222 {
 223         return (void *)1;
 224 }
 225
 226 static void libipw_crypt_null_deinit(void *priv)
 227 {
 228 }
 229
 230 static const struct libipw_crypto_ops libipw_crypt_null = {
 231         .name = "NULL",
 232         .init = libipw_crypt_null_init,
 233         .deinit = libipw_crypt_null_deinit,
 234         .owner = THIS_MODULE,
 235 };
 236
 237 int __init libipw_crypto_init(void)
 238 {
 239         return libipw_register_crypto_ops(&libipw_crypt_null);
 240 }
 241
 242 void libipw_crypto_exit(void)
 243 {
 244         libipw_unregister_crypto_ops(&libipw_crypt_null);
 245         BUG_ON(!list_empty(&libipw_crypto_algs));
 246 }