madwifi/net80211/ieee80211_crypto.h
2007-10-04 13:07:51 +00:00

208 lines
8.0 KiB
C

/*-
* Copyright (c) 2001 Atsushi Onoe
* Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $Id$
*/
#ifndef _NET80211_IEEE80211_CRYPTO_H_
#define _NET80211_IEEE80211_CRYPTO_H_
/*
* 802.11 protocol crypto-related definitions.
*/
#define IEEE80211_KEYBUF_SIZE 16
#define IEEE80211_MICBUF_SIZE (8 + 8) /* space for both TX & RX keys */
#define IEEE80211_TID_SIZE 17 /* total number of TIDs */
/*
* Old WEP-style key. Deprecated.
*/
struct ieee80211_wepkey {
u_int wk_len; /* key length in bytes */
u_int8_t wk_key[IEEE80211_KEYBUF_SIZE];
};
struct ieee80211_cipher;
/*
* Crypto key state. There is sufficient room for all supported
* ciphers (see below). The underlying ciphers are handled
* separately through loadable cipher modules that register with
* the generic crypto support. A key has a reference to an instance
* of the cipher; any per-key state is hung off wk_private by the
* cipher when it is attached. Ciphers are automatically called
* to detach and cleanup any such state when the key is deleted.
*
* The generic crypto support handles encap/decap of cipher-related
* frame contents for both hardware- and software-based implementations.
* A key requiring software crypto support is automatically flagged and
* the cipher is expected to honor this and do the necessary work.
* Ciphers such as TKIP may also support mixed hardware/software
* encrypt/decrypt and MIC processing.
*/
typedef u_int16_t ieee80211_keyix_t;
/* XXX pack better? */
/* XXX 48-bit rsc/tsc */
struct ieee80211_key {
u_int8_t wk_keylen; /* key length in bytes */
u_int8_t wk_flags;
#define IEEE80211_KEY_XMIT 0x01 /* key used for xmit */
#define IEEE80211_KEY_RECV 0x02 /* key used for recv */
#define IEEE80211_KEY_GROUP 0x04 /* key used for WPA group operation */
#define IEEE80211_KEY_SWCRYPT 0x10 /* host-based encrypt/decrypt */
#define IEEE80211_KEY_SWMIC 0x20 /* host-based enmic/demic */
ieee80211_keyix_t wk_keyix; /* key index */
u_int8_t wk_key[IEEE80211_KEYBUF_SIZE+IEEE80211_MICBUF_SIZE];
#define wk_txmic wk_key+IEEE80211_KEYBUF_SIZE+0 /* XXX can't () right */
#define wk_rxmic wk_key+IEEE80211_KEYBUF_SIZE+8 /* XXX can't () right */
u_int64_t wk_keyrsc[IEEE80211_TID_SIZE]; /* key receive sequence counter */
u_int64_t wk_keytsc; /* key transmit sequence counter */
const struct ieee80211_cipher *wk_cipher;
void *wk_private; /* private cipher state */
};
#define IEEE80211_KEY_COMMON /* common flags passed in by apps */\
(IEEE80211_KEY_XMIT | IEEE80211_KEY_RECV | IEEE80211_KEY_GROUP)
/*
* NB: these values are ordered carefully; there are lots of
* of implications in any reordering. In particular beware
* that 4 is not used to avoid conflicting with IEEE80211_F_PRIVACY.
*/
#define IEEE80211_CIPHER_WEP 0
#define IEEE80211_CIPHER_TKIP 1
#define IEEE80211_CIPHER_AES_OCB 2
#define IEEE80211_CIPHER_AES_CCM 3
#define IEEE80211_CIPHER_CKIP 5
#define IEEE80211_CIPHER_NONE 6 /* pseudo value */
#define IEEE80211_CIPHER_MAX (IEEE80211_CIPHER_NONE + 1)
#define IEEE80211_KEYIX_NONE ((ieee80211_keyix_t) -1)
#if defined(__KERNEL__) || defined(_KERNEL)
struct ieee80211com;
struct ieee80211vap;
struct ieee80211_node;
struct sk_buff;
void ieee80211_crypto_attach(struct ieee80211com *);
void ieee80211_crypto_detach(struct ieee80211com *);
void ieee80211_crypto_vattach(struct ieee80211vap *);
void ieee80211_crypto_vdetach(struct ieee80211vap *);
int ieee80211_crypto_newkey(struct ieee80211vap *, int, int,
struct ieee80211_key *);
int ieee80211_crypto_delkey(struct ieee80211vap *, struct ieee80211_key *,
struct ieee80211_node *);
int ieee80211_crypto_setkey(struct ieee80211vap *, struct ieee80211_key *,
const u_int8_t macaddr[IEEE80211_ADDR_LEN], struct ieee80211_node *);
void ieee80211_crypto_delglobalkeys(struct ieee80211vap *);
/*
* Template for a supported cipher. Ciphers register with the
* crypto code and are typically loaded as separate modules
* (the null cipher is always present).
* XXX may need refcnts
*/
struct ieee80211_cipher {
const char *ic_name; /* printable name */
u_int ic_cipher; /* IEEE80211_CIPHER_* */
u_int ic_header; /* size of privacy header (bytes) */
u_int ic_trailer; /* size of privacy trailer (bytes) */
u_int ic_miclen; /* size of mic trailer (bytes) */
void *(*ic_attach)(struct ieee80211vap *, struct ieee80211_key *);
void (*ic_detach)(struct ieee80211_key *);
int (*ic_setkey)(struct ieee80211_key *);
int (*ic_encap)(struct ieee80211_key *, struct sk_buff *, u_int8_t);
int (*ic_decap)(struct ieee80211_key *, struct sk_buff *, int);
int (*ic_enmic)(struct ieee80211_key *, struct sk_buff *, int);
int (*ic_demic)(struct ieee80211_key *, struct sk_buff *, int);
};
extern const struct ieee80211_cipher ieee80211_cipher_none;
void ieee80211_crypto_register(const struct ieee80211_cipher *);
void ieee80211_crypto_unregister(const struct ieee80211_cipher *);
int ieee80211_crypto_available(struct ieee80211vap*, u_int);
struct ieee80211_key *ieee80211_crypto_encap(struct ieee80211_node *,
struct sk_buff *);
struct ieee80211_key *ieee80211_crypto_decap(struct ieee80211_node *,
struct sk_buff *, int);
/*
* Check and remove any MIC.
*/
static __inline int
ieee80211_crypto_demic(struct ieee80211vap *vap, struct ieee80211_key *k,
struct sk_buff *skb, int hdrlen)
{
const struct ieee80211_cipher *cip = k->wk_cipher;
return (cip->ic_miclen > 0 ? cip->ic_demic(k, skb, hdrlen) : 1);
}
/*
* Add any MIC.
*/
static __inline int
ieee80211_crypto_enmic(struct ieee80211vap *vap, struct ieee80211_key *k,
struct sk_buff *skb, int force)
{
const struct ieee80211_cipher *cip = k->wk_cipher;
return (cip->ic_miclen > 0 ? cip->ic_enmic(k, skb, force) : 1);
}
/*
* Reset key state to an unused state. The crypto
* key allocation mechanism ensures other state (e.g.
* key data) is properly setup before a key is used.
*/
static __inline void
ieee80211_crypto_resetkey(struct ieee80211vap *vap, struct ieee80211_key *k,
ieee80211_keyix_t ix)
{
k->wk_cipher = &ieee80211_cipher_none;;
k->wk_private = k->wk_cipher->ic_attach(vap, k);
k->wk_keyix = ix;
k->wk_flags = IEEE80211_KEY_XMIT | IEEE80211_KEY_RECV;
}
/*
* Crypto-related notification methods.
*/
void ieee80211_notify_replay_failure(struct ieee80211vap *,
const struct ieee80211_frame *, const struct ieee80211_key *,
u_int64_t rsc);
void ieee80211_notify_michael_failure(struct ieee80211vap *,
const struct ieee80211_frame *, ieee80211_keyix_t keyix);
#endif /* defined(__KERNEL__) || defined(_KERNEL) */
#endif /* _NET80211_IEEE80211_CRYPTO_H_ */