ieee80211_crypto.h revision 144618
1/*- 2 * Copyright (c) 2001 Atsushi Onoe 3 * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote products 15 * derived from this software without specific prior written permission. 16 * 17 * Alternatively, this software may be distributed under the terms of the 18 * GNU General Public License ("GPL") version 2 as published by the Free 19 * Software Foundation. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 * 32 * $FreeBSD: head/sys/net80211/ieee80211_crypto.h 144618 2005-04-04 04:27:20Z sam $ 33 */ 34#ifndef _NET80211_IEEE80211_CRYPTO_H_ 35#define _NET80211_IEEE80211_CRYPTO_H_ 36 37/* 38 * 802.11 protocol crypto-related definitions. 39 */ 40#define IEEE80211_KEYBUF_SIZE 16 41#define IEEE80211_MICBUF_SIZE (8+8) /* space for both tx+rx keys */ 42 43/* 44 * Old WEP-style key. Deprecated. 45 */ 46struct ieee80211_wepkey { 47 u_int wk_len; /* key length in bytes */ 48 u_int8_t wk_key[IEEE80211_KEYBUF_SIZE]; 49}; 50 51struct ieee80211_cipher; 52 53/* 54 * Crypto key state. There is sufficient room for all supported 55 * ciphers (see below). The underlying ciphers are handled 56 * separately through loadable cipher modules that register with 57 * the generic crypto support. A key has a reference to an instance 58 * of the cipher; any per-key state is hung off wk_private by the 59 * cipher when it is attached. Ciphers are automatically called 60 * to detach and cleanup any such state when the key is deleted. 61 * 62 * The generic crypto support handles encap/decap of cipher-related 63 * frame contents for both hardware- and software-based implementations. 64 * A key requiring software crypto support is automatically flagged and 65 * the cipher is expected to honor this and do the necessary work. 66 * Ciphers such as TKIP may also support mixed hardware/software 67 * encrypt/decrypt and MIC processing. 68 */ 69/* XXX need key index typedef */ 70/* XXX pack better? */ 71/* XXX 48-bit rsc/tsc */ 72struct ieee80211_key { 73 u_int8_t wk_keylen; /* key length in bytes */ 74 u_int8_t wk_flags; 75#define IEEE80211_KEY_XMIT 0x01 /* key used for xmit */ 76#define IEEE80211_KEY_RECV 0x02 /* key used for recv */ 77#define IEEE80211_KEY_SWCRYPT 0x04 /* host-based encrypt/decrypt */ 78#define IEEE80211_KEY_SWMIC 0x08 /* host-based enmic/demic */ 79 u_int16_t wk_keyix; /* key index */ 80 u_int8_t wk_key[IEEE80211_KEYBUF_SIZE+IEEE80211_MICBUF_SIZE]; 81#define wk_txmic wk_key+IEEE80211_KEYBUF_SIZE+0 /* XXX can't () right */ 82#define wk_rxmic wk_key+IEEE80211_KEYBUF_SIZE+8 /* XXX can't () right */ 83 u_int64_t wk_keyrsc; /* key receive sequence counter */ 84 u_int64_t wk_keytsc; /* key transmit sequence counter */ 85 const struct ieee80211_cipher *wk_cipher; 86 void *wk_private; /* private cipher state */ 87}; 88 89/* 90 * NB: these values are ordered carefully; there are lots of 91 * of implications in any reordering. In particular beware 92 * that 4 is not used to avoid conflicting with IEEE80211_F_PRIVACY. 93 */ 94#define IEEE80211_CIPHER_WEP 0 95#define IEEE80211_CIPHER_TKIP 1 96#define IEEE80211_CIPHER_AES_OCB 2 97#define IEEE80211_CIPHER_AES_CCM 3 98#define IEEE80211_CIPHER_CKIP 5 99#define IEEE80211_CIPHER_NONE 6 /* pseudo value */ 100 101#define IEEE80211_CIPHER_MAX (IEEE80211_CIPHER_NONE+1) 102 103#define IEEE80211_KEYIX_NONE ((u_int16_t) -1) 104 105#if defined(__KERNEL__) || defined(_KERNEL) 106 107struct ieee80211com; 108struct ieee80211_node; 109struct mbuf; 110 111/* 112 * Crypto state kept in each ieee80211com. Some of this 113 * can/should be shared when virtual AP's are supported. 114 * 115 * XXX save reference to ieee80211com to properly encapsulate state. 116 * XXX split out crypto capabilities from ic_caps 117 */ 118struct ieee80211_crypto_state { 119 struct ieee80211_key cs_nw_keys[IEEE80211_WEP_NKID]; 120 u_int16_t cs_def_txkey; /* default/group tx key index */ 121 122 int (*cs_key_alloc)(struct ieee80211com *, 123 const struct ieee80211_key *); 124 int (*cs_key_delete)(struct ieee80211com *, 125 const struct ieee80211_key *); 126 int (*cs_key_set)(struct ieee80211com *, 127 const struct ieee80211_key *, 128 const u_int8_t mac[IEEE80211_ADDR_LEN]); 129 void (*cs_key_update_begin)(struct ieee80211com *); 130 void (*cs_key_update_end)(struct ieee80211com *); 131}; 132 133void ieee80211_crypto_attach(struct ieee80211com *); 134void ieee80211_crypto_detach(struct ieee80211com *); 135int ieee80211_crypto_newkey(struct ieee80211com *, 136 int cipher, struct ieee80211_key *); 137int ieee80211_crypto_delkey(struct ieee80211com *, 138 struct ieee80211_key *); 139int ieee80211_crypto_setkey(struct ieee80211com *, 140 struct ieee80211_key *, const u_int8_t macaddr[IEEE80211_ADDR_LEN]); 141void ieee80211_crypto_delglobalkeys(struct ieee80211com *); 142 143/* 144 * Template for a supported cipher. Ciphers register with the 145 * crypto code and are typically loaded as separate modules 146 * (the null cipher is always present). 147 * XXX may need refcnts 148 */ 149struct ieee80211_cipher { 150 const char *ic_name; /* printable name */ 151 u_int ic_cipher; /* IEEE80211_CIPHER_* */ 152 u_int ic_header; /* size of privacy header (bytes) */ 153 u_int ic_trailer; /* size of privacy trailer (bytes) */ 154 u_int ic_miclen; /* size of mic trailer (bytes) */ 155 void* (*ic_attach)(struct ieee80211com *, struct ieee80211_key *); 156 void (*ic_detach)(struct ieee80211_key *); 157 int (*ic_setkey)(struct ieee80211_key *); 158 int (*ic_encap)(struct ieee80211_key *, struct mbuf *, 159 u_int8_t keyid); 160 int (*ic_decap)(struct ieee80211_key *, struct mbuf *); 161 int (*ic_enmic)(struct ieee80211_key *, struct mbuf *); 162 int (*ic_demic)(struct ieee80211_key *, struct mbuf *); 163}; 164extern const struct ieee80211_cipher ieee80211_cipher_none; 165 166void ieee80211_crypto_register(const struct ieee80211_cipher *); 167void ieee80211_crypto_unregister(const struct ieee80211_cipher *); 168int ieee80211_crypto_available(u_int cipher); 169 170struct ieee80211_key *ieee80211_crypto_encap(struct ieee80211com *, 171 struct ieee80211_node *, struct mbuf *); 172struct ieee80211_key *ieee80211_crypto_decap(struct ieee80211com *, 173 struct ieee80211_node *, struct mbuf *); 174 175/* 176 * Check and remove any MIC. 177 */ 178static __inline int 179ieee80211_crypto_demic(struct ieee80211com *ic, struct ieee80211_key *k, 180 struct mbuf *m) 181{ 182 const struct ieee80211_cipher *cip = k->wk_cipher; 183 return (cip->ic_miclen > 0 ? cip->ic_demic(k, m) : 1); 184} 185 186/* 187 * Add any MIC. 188 */ 189static __inline int 190ieee80211_crypto_enmic(struct ieee80211com *ic, 191 struct ieee80211_key *k, struct mbuf *m) 192{ 193 const struct ieee80211_cipher *cip = k->wk_cipher; 194 return (cip->ic_miclen > 0 ? cip->ic_enmic(k, m) : 1); 195} 196 197/* 198 * Reset key state to an unused state. The crypto 199 * key allocation mechanism insures other state (e.g. 200 * key data) is properly setup before a key is used. 201 */ 202static __inline void 203ieee80211_crypto_resetkey(struct ieee80211com *ic, 204 struct ieee80211_key *k, u_int16_t ix) 205{ 206 k->wk_cipher = &ieee80211_cipher_none;; 207 k->wk_private = k->wk_cipher->ic_attach(ic, k); 208 k->wk_keyix = ix; 209 k->wk_flags = IEEE80211_KEY_XMIT | IEEE80211_KEY_RECV; 210} 211 212/* 213 * Crypt-related notification methods. 214 */ 215void ieee80211_notify_replay_failure(struct ieee80211com *, 216 const struct ieee80211_frame *, const struct ieee80211_key *, 217 u_int64_t rsc); 218void ieee80211_notify_michael_failure(struct ieee80211com *, 219 const struct ieee80211_frame *, u_int keyix); 220#endif /* defined(__KERNEL__) || defined(_KERNEL) */ 221#endif /* _NET80211_IEEE80211_CRYPTO_H_ */ 222