ieee80211_crypt.h

Source for the 802.11 (wireless) network stack for Linux

/*
 * Original code based on Host AP (software wireless LAN access point) driver
 * for Intersil Prism2/2.5/3.
 *
 * Copyright (c) 2001-2002, SSH Communications Security Corp and Jouni Malinen
 * <[e-mail]>
 * Copyright (c) 2002-2003, Jouni Malinen <[e-mail]>
 *
 * Adaption to a generic IEEE 802.11 stack by James Ketrenos
 * <[e-mail]>
 *
 * Copyright (c) 2004, Intel Corporation
 *
 * 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.
 */

/*
 * This file defines the interface to the ieee80211 crypto module.
 */
#ifndef IEEE80211_CRYPT_H
#define IEEE80211_CRYPT_H

#include <linux/skbuff.h>

enum {
	IEEE80211_CRYPTO_TKIP_COUNTERMEASURES = (1 << 0),
};

struct ieee80211_crypto_ops {
	const char *name;

	/* init new crypto context (e.g., allocate private data space,
	 * select IV, etc.); returns NULL on failure or pointer to allocated
	 * private data on success */
	void *(*init) (int keyidx);

	/* deinitialize crypto context and free allocated private data */
	void (*deinit) (void *priv);

	int (*build_iv) (struct sk_buff * skb, int hdr_len, void *priv);

	/* encrypt/decrypt return < 0 on error or >= 0 on success. The return
	 * value from decrypt_mpdu is passed as the keyidx value for
	 * decrypt_msdu. skb must have enough head and tail room for the
	 * encryption; if not, error will be returned; these functions are
	 * called for all MPDUs (i.e., fragments).
	 */
	int (*encrypt_mpdu) (struct sk_buff * skb, int hdr_len, void *priv);
	int (*decrypt_mpdu) (struct sk_buff * skb, int hdr_len, void *priv);

	/* These functions are called for full MSDUs, i.e. full frames.
	 * These can be NULL if full MSDU operations are not needed. */
	int (*encrypt_msdu) (struct sk_buff * skb, int hdr_len, void *priv);
	int (*decrypt_msdu) (struct sk_buff * skb, int keyidx, int hdr_len,
			     void *priv);

	int (*set_key) (void *key, int len, u8 * seq, void *priv);
	int (*get_key) (void *key, int len, u8 * seq, void *priv);

	/* procfs handler for printing out key information and possible
	 * statistics */
	char *(*print_stats) (char *p, void *priv);

	/* Crypto specific flag get/set for configuration settings */
	unsigned long (*get_flags) (void *priv);
	unsigned long (*set_flags) (unsigned long flags, void *priv);

	/* maximum number of bytes added by encryption; encrypt buf is
	 * allocated with extra_prefix_len bytes, copy of in_buf, and
	 * extra_postfix_len; encrypt need not use all this space, but
	 * the result must start at the beginning of the buffer and correct
	 * length must be returned */
	int extra_mpdu_prefix_len, extra_mpdu_postfix_len;
	int extra_msdu_prefix_len, extra_msdu_postfix_len;

	struct module *owner;
};

struct ieee80211_crypt_data {
	struct list_head list;	/* delayed deletion list */
	struct ieee80211_crypto_ops *ops;
	void *priv;
	atomic_t refcnt;
};

int ieee80211_register_crypto_ops(struct ieee80211_crypto_ops *ops);
int ieee80211_unregister_crypto_ops(struct ieee80211_crypto_ops *ops);
struct ieee80211_crypto_ops *ieee80211_get_crypto_ops(const char *name);
void ieee80211_crypt_deinit_entries(struct ieee80211_device *, int);
void ieee80211_crypt_deinit_handler(unsigned long);
void ieee80211_crypt_delayed_deinit(struct ieee80211_device *ieee,
				    struct ieee80211_crypt_data **crypt);
void ieee80211_crypt_quiescing(struct ieee80211_device *ieee);

#endif