[NET] ieee80211 subsystem

Contributors:
Host AP contributors
James Ketrenos <jketreno@linux.intel.com>
Francois Romieu <romieu@fr.zoreil.com>
Adrian Bunk <bunk@stusta.de>
Matthew Galgoci <mgalgoci@parcelfarce.linux.th
eplanet.co.uk>
diff --git a/net/ieee80211/ieee80211_crypt.c b/net/ieee80211/ieee80211_crypt.c
new file mode 100644
index 0000000..05a6f2f
--- /dev/null
+++ b/net/ieee80211/ieee80211_crypt.c
@@ -0,0 +1,259 @@
+/*
+ * Host AP crypto routines
+ *
+ * Copyright (c) 2002-2003, Jouni Malinen <jkmaline@cc.hut.fi>
+ * Portions Copyright (C) 2004, Intel Corporation <jketreno@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation. See README and COPYING for
+ * more details.
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <asm/string.h>
+#include <asm/errno.h>
+
+#include <net/ieee80211.h>
+
+MODULE_AUTHOR("Jouni Malinen");
+MODULE_DESCRIPTION("HostAP crypto");
+MODULE_LICENSE("GPL");
+
+struct ieee80211_crypto_alg {
+	struct list_head list;
+	struct ieee80211_crypto_ops *ops;
+};
+
+
+struct ieee80211_crypto {
+	struct list_head algs;
+	spinlock_t lock;
+};
+
+static struct ieee80211_crypto *hcrypt;
+
+void ieee80211_crypt_deinit_entries(struct ieee80211_device *ieee,
+					   int force)
+{
+	struct list_head *ptr, *n;
+	struct ieee80211_crypt_data *entry;
+
+	for (ptr = ieee->crypt_deinit_list.next, n = ptr->next;
+	     ptr != &ieee->crypt_deinit_list; ptr = n, n = ptr->next) {
+		entry = list_entry(ptr, struct ieee80211_crypt_data, list);
+
+		if (atomic_read(&entry->refcnt) != 0 && !force)
+			continue;
+
+		list_del(ptr);
+
+		if (entry->ops) {
+			entry->ops->deinit(entry->priv);
+			module_put(entry->ops->owner);
+		}
+		kfree(entry);
+	}
+}
+
+void ieee80211_crypt_deinit_handler(unsigned long data)
+{
+	struct ieee80211_device *ieee = (struct ieee80211_device *)data;
+	unsigned long flags;
+
+	spin_lock_irqsave(&ieee->lock, flags);
+	ieee80211_crypt_deinit_entries(ieee, 0);
+	if (!list_empty(&ieee->crypt_deinit_list)) {
+		printk(KERN_DEBUG "%s: entries remaining in delayed crypt "
+		       "deletion list\n", ieee->dev->name);
+		ieee->crypt_deinit_timer.expires = jiffies + HZ;
+		add_timer(&ieee->crypt_deinit_timer);
+	}
+	spin_unlock_irqrestore(&ieee->lock, flags);
+
+}
+
+void ieee80211_crypt_delayed_deinit(struct ieee80211_device *ieee,
+				    struct ieee80211_crypt_data **crypt)
+{
+	struct ieee80211_crypt_data *tmp;
+	unsigned long flags;
+
+	if (*crypt == NULL)
+		return;
+
+	tmp = *crypt;
+	*crypt = NULL;
+
+	/* must not run ops->deinit() while there may be pending encrypt or
+	 * decrypt operations. Use a list of delayed deinits to avoid needing
+	 * locking. */
+
+	spin_lock_irqsave(&ieee->lock, flags);
+	list_add(&tmp->list, &ieee->crypt_deinit_list);
+	if (!timer_pending(&ieee->crypt_deinit_timer)) {
+		ieee->crypt_deinit_timer.expires = jiffies + HZ;
+		add_timer(&ieee->crypt_deinit_timer);
+	}
+	spin_unlock_irqrestore(&ieee->lock, flags);
+}
+
+int ieee80211_register_crypto_ops(struct ieee80211_crypto_ops *ops)
+{
+	unsigned long flags;
+	struct ieee80211_crypto_alg *alg;
+
+	if (hcrypt == NULL)
+		return -1;
+
+	alg = kmalloc(sizeof(*alg), GFP_KERNEL);
+	if (alg == NULL)
+		return -ENOMEM;
+
+	memset(alg, 0, sizeof(*alg));
+	alg->ops = ops;
+
+	spin_lock_irqsave(&hcrypt->lock, flags);
+	list_add(&alg->list, &hcrypt->algs);
+	spin_unlock_irqrestore(&hcrypt->lock, flags);
+
+	printk(KERN_DEBUG "ieee80211_crypt: registered algorithm '%s'\n",
+	       ops->name);
+
+	return 0;
+}
+
+int ieee80211_unregister_crypto_ops(struct ieee80211_crypto_ops *ops)
+{
+	unsigned long flags;
+	struct list_head *ptr;
+	struct ieee80211_crypto_alg *del_alg = NULL;
+
+	if (hcrypt == NULL)
+		return -1;
+
+	spin_lock_irqsave(&hcrypt->lock, flags);
+	for (ptr = hcrypt->algs.next; ptr != &hcrypt->algs; ptr = ptr->next) {
+		struct ieee80211_crypto_alg *alg =
+			(struct ieee80211_crypto_alg *) ptr;
+		if (alg->ops == ops) {
+			list_del(&alg->list);
+			del_alg = alg;
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&hcrypt->lock, flags);
+
+	if (del_alg) {
+		printk(KERN_DEBUG "ieee80211_crypt: unregistered algorithm "
+		       "'%s'\n", ops->name);
+		kfree(del_alg);
+	}
+
+	return del_alg ? 0 : -1;
+}
+
+
+struct ieee80211_crypto_ops * ieee80211_get_crypto_ops(const char *name)
+{
+	unsigned long flags;
+	struct list_head *ptr;
+	struct ieee80211_crypto_alg *found_alg = NULL;
+
+	if (hcrypt == NULL)
+		return NULL;
+
+	spin_lock_irqsave(&hcrypt->lock, flags);
+	for (ptr = hcrypt->algs.next; ptr != &hcrypt->algs; ptr = ptr->next) {
+		struct ieee80211_crypto_alg *alg =
+			(struct ieee80211_crypto_alg *) ptr;
+		if (strcmp(alg->ops->name, name) == 0) {
+			found_alg = alg;
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&hcrypt->lock, flags);
+
+	if (found_alg)
+		return found_alg->ops;
+	else
+		return NULL;
+}
+
+
+static void * ieee80211_crypt_null_init(int keyidx) { return (void *) 1; }
+static void ieee80211_crypt_null_deinit(void *priv) {}
+
+static struct ieee80211_crypto_ops ieee80211_crypt_null = {
+	.name			= "NULL",
+	.init			= ieee80211_crypt_null_init,
+	.deinit			= ieee80211_crypt_null_deinit,
+	.encrypt_mpdu		= NULL,
+	.decrypt_mpdu		= NULL,
+	.encrypt_msdu		= NULL,
+	.decrypt_msdu		= NULL,
+	.set_key		= NULL,
+	.get_key		= NULL,
+	.extra_prefix_len	= 0,
+	.extra_postfix_len	= 0,
+	.owner			= THIS_MODULE,
+};
+
+
+static int __init ieee80211_crypto_init(void)
+{
+	int ret = -ENOMEM;
+
+	hcrypt = kmalloc(sizeof(*hcrypt), GFP_KERNEL);
+	if (!hcrypt)
+		goto out;
+
+	memset(hcrypt, 0, sizeof(*hcrypt));
+	INIT_LIST_HEAD(&hcrypt->algs);
+	spin_lock_init(&hcrypt->lock);
+
+	ret = ieee80211_register_crypto_ops(&ieee80211_crypt_null);
+	if (ret < 0) {
+		kfree(hcrypt);
+		hcrypt = NULL;
+	}
+out:
+	return ret;
+}
+
+
+static void __exit ieee80211_crypto_deinit(void)
+{
+	struct list_head *ptr, *n;
+
+	if (hcrypt == NULL)
+		return;
+
+	for (ptr = hcrypt->algs.next, n = ptr->next; ptr != &hcrypt->algs;
+	     ptr = n, n = ptr->next) {
+		struct ieee80211_crypto_alg *alg =
+			(struct ieee80211_crypto_alg *) ptr;
+		list_del(ptr);
+		printk(KERN_DEBUG "ieee80211_crypt: unregistered algorithm "
+		       "'%s' (deinit)\n", alg->ops->name);
+		kfree(alg);
+	}
+
+	kfree(hcrypt);
+}
+
+EXPORT_SYMBOL(ieee80211_crypt_deinit_entries);
+EXPORT_SYMBOL(ieee80211_crypt_deinit_handler);
+EXPORT_SYMBOL(ieee80211_crypt_delayed_deinit);
+
+EXPORT_SYMBOL(ieee80211_register_crypto_ops);
+EXPORT_SYMBOL(ieee80211_unregister_crypto_ops);
+EXPORT_SYMBOL(ieee80211_get_crypto_ops);
+
+module_init(ieee80211_crypto_init);
+module_exit(ieee80211_crypto_deinit);