freebsd-dev/sys/net80211/ieee80211_crypto.h
Sam Leffler c1225b52f6 Split crypto tx+rx key indices and add a key index -> node mapping table:
Crypto changes:
o change driver/net80211 key_alloc api to return tx+rx key indices; a
  driver can leave the rx key index set to IEEE80211_KEYIX_NONE or set
  it to be the same as the tx key index (the former disables use of
  the key index in building the keyix->node mapping table and is the
  default setup for naive drivers by null_key_alloc)
o add cs_max_keyid to crypto state to specify the max h/w key index a
  driver will return; this is used to allocate the key index mapping
  table and to bounds check table loookups
o while here introduce ieee80211_keyix (finally) for the type of a h/w
  key index
o change crypto notifiers for rx failures to pass the rx key index up
  as appropriate (michael failure, replay, etc.)

Node table changes:
o optionally allocate a h/w key index to node mapping table for the
  station table using the max key index setting supplied by drivers
  (note the scan table does not get a map)
o defer node table allocation to lateattach so the driver has a chance
  to set the max key id to size the key index map
o while here also defer the aid bitmap allocation
o add new ieee80211_find_rxnode_withkey api to find a sta/node entry
  on frame receive with an optional h/w key index to use in checking
  mapping table; also updates the map if it does a hash lookup and the
  found node has a rx key index set in the unicast key; note this work
  is separated from the old ieee80211_find_rxnode call so drivers do
  not need to be aware of the new mechanism
o move some node table manipulation under the node table lock to close
  a race on node delete
o add ieee80211_node_delucastkey to do the dirty work of deleting
  unicast key state for a node (deletes any key and handles key map
  references)

Ath driver:
o nuke private sc_keyixmap mechansim in favor of net80211 support
o update key alloc api

These changes close several race conditions for the ath driver operating
in ap mode.  Other drivers should see no change.  Station mode operation
for ath no longer uses the key index map but performance tests show no
noticeable change and this will be fixed when the scan table is eliminated
with the new scanning support.

Tested by:	Michal Mertl, avatar, others
Reviewed by:	avatar, others
MFC after:	2 weeks
2005-08-08 18:46:36 +00:00

228 lines
8.7 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.
*
* $FreeBSD$
*/
#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 */
/*
* 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; /* h/w key index */
struct ieee80211_key {
u_int8_t wk_keylen; /* key length in bytes */
u_int8_t wk_pad;
u_int16_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 wk_keyix; /* h/w key index */
ieee80211_keyix wk_rxkeyix; /* optional h/w rx 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; /* 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) -1)
#if defined(__KERNEL__) || defined(_KERNEL)
struct ieee80211com;
struct ieee80211_node;
struct mbuf;
/*
* Crypto state kept in each ieee80211com. Some of this
* can/should be shared when virtual AP's are supported.
*
* XXX save reference to ieee80211com to properly encapsulate state.
* XXX split out crypto capabilities from ic_caps
*/
struct ieee80211_crypto_state {
struct ieee80211_key cs_nw_keys[IEEE80211_WEP_NKID];
ieee80211_keyix cs_def_txkey; /* default/group tx key index */
u_int16_t cs_max_keyix; /* max h/w key index */
int (*cs_key_alloc)(struct ieee80211com *,
const struct ieee80211_key *,
ieee80211_keyix *, ieee80211_keyix *);
int (*cs_key_delete)(struct ieee80211com *,
const struct ieee80211_key *);
int (*cs_key_set)(struct ieee80211com *,
const struct ieee80211_key *,
const u_int8_t mac[IEEE80211_ADDR_LEN]);
void (*cs_key_update_begin)(struct ieee80211com *);
void (*cs_key_update_end)(struct ieee80211com *);
};
void ieee80211_crypto_attach(struct ieee80211com *);
void ieee80211_crypto_detach(struct ieee80211com *);
int ieee80211_crypto_newkey(struct ieee80211com *,
int cipher, int flags, struct ieee80211_key *);
int ieee80211_crypto_delkey(struct ieee80211com *,
struct ieee80211_key *);
int ieee80211_crypto_setkey(struct ieee80211com *,
struct ieee80211_key *, const u_int8_t macaddr[IEEE80211_ADDR_LEN]);
void ieee80211_crypto_delglobalkeys(struct ieee80211com *);
/*
* 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 ieee80211com *, struct ieee80211_key *);
void (*ic_detach)(struct ieee80211_key *);
int (*ic_setkey)(struct ieee80211_key *);
int (*ic_encap)(struct ieee80211_key *, struct mbuf *,
u_int8_t keyid);
int (*ic_decap)(struct ieee80211_key *, struct mbuf *, int);
int (*ic_enmic)(struct ieee80211_key *, struct mbuf *, int);
int (*ic_demic)(struct ieee80211_key *, struct mbuf *, 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(u_int cipher);
struct ieee80211_key *ieee80211_crypto_encap(struct ieee80211com *,
struct ieee80211_node *, struct mbuf *);
struct ieee80211_key *ieee80211_crypto_decap(struct ieee80211com *,
struct ieee80211_node *, struct mbuf *, int);
/*
* Check and remove any MIC.
*/
static __inline int
ieee80211_crypto_demic(struct ieee80211com *ic, struct ieee80211_key *k,
struct mbuf *m, int force)
{
const struct ieee80211_cipher *cip = k->wk_cipher;
return (cip->ic_miclen > 0 ? cip->ic_demic(k, m, force) : 1);
}
/*
* Add any MIC.
*/
static __inline int
ieee80211_crypto_enmic(struct ieee80211com *ic,
struct ieee80211_key *k, struct mbuf *m, int force)
{
const struct ieee80211_cipher *cip = k->wk_cipher;
return (cip->ic_miclen > 0 ? cip->ic_enmic(k, m, force) : 1);
}
/*
* Reset key state to an unused state. The crypto
* key allocation mechanism insures other state (e.g.
* key data) is properly setup before a key is used.
*/
static __inline void
ieee80211_crypto_resetkey(struct ieee80211com *ic,
struct ieee80211_key *k, ieee80211_keyix ix)
{
k->wk_cipher = &ieee80211_cipher_none;;
k->wk_private = k->wk_cipher->ic_attach(ic, k);
k->wk_keyix = k->wk_rxkeyix = ix;
k->wk_flags = IEEE80211_KEY_XMIT | IEEE80211_KEY_RECV;
}
/*
* Crypt-related notification methods.
*/
void ieee80211_notify_replay_failure(struct ieee80211com *,
const struct ieee80211_frame *, const struct ieee80211_key *,
u_int64_t rsc);
void ieee80211_notify_michael_failure(struct ieee80211com *,
const struct ieee80211_frame *, u_int keyix);
#endif /* defined(__KERNEL__) || defined(_KERNEL) */
#endif /* _NET80211_IEEE80211_CRYPTO_H_ */