1 /* $NetBSD: ieee80211_crypto.h,v 1.12 2017/12/10 08:56:23 maxv Exp $ */
2 /*-
3 * Copyright (c) 2001 Atsushi Onoe
4 * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. The name of the author may not be used to endorse or promote products
16 * derived from this software without specific prior written permission.
17 *
18 * Alternatively, this software may be distributed under the terms of the
19 * GNU General Public License ("GPL") version 2 as published by the Free
20 * Software Foundation.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 *
33 * $FreeBSD: src/sys/net80211/ieee80211_crypto.h,v 1.10 2005/08/08 18:46:35 sam Exp $
34 */
35 #ifndef _NET80211_IEEE80211_CRYPTO_H_
36 #define _NET80211_IEEE80211_CRYPTO_H_
37
38 /*
39 * 802.11 protocol crypto-related definitions.
40 */
41 #define IEEE80211_KEYBUF_SIZE 16
42 #define IEEE80211_MICBUF_SIZE (8+8) /* space for both tx+rx keys */
43
44 /*
45 * Old WEP-style key. Deprecated.
46 */
47 struct ieee80211_wepkey {
48 u_int wk_len; /* key length in bytes */
49 u_int8_t wk_key[IEEE80211_KEYBUF_SIZE];
50 };
51
52 struct ieee80211_cipher;
53
54 /*
55 * Crypto key state. There is sufficient room for all supported
56 * ciphers (see below). The underlying ciphers are handled
57 * separately through loadable cipher modules that register with
58 * the generic crypto support. A key has a reference to an instance
59 * of the cipher; any per-key state is hung off wk_private by the
60 * cipher when it is attached. Ciphers are automatically called
61 * to detach and cleanup any such state when the key is deleted.
62 *
63 * The generic crypto support handles encap/decap of cipher-related
64 * frame contents for both hardware- and software-based implementations.
65 * A key requiring software crypto support is automatically flagged and
66 * the cipher is expected to honor this and do the necessary work.
67 * Ciphers such as TKIP may also support mixed hardware/software
68 * encrypt/decrypt and MIC processing.
69 */
70 typedef u_int16_t ieee80211_keyix; /* h/w key index */
71
72 struct ieee80211_key {
73 u_int8_t wk_keylen; /* key length in bytes */
74 u_int8_t wk_pad;
75 u_int16_t wk_flags;
76 #define IEEE80211_KEY_XMIT 0x01 /* key used for xmit */
77 #define IEEE80211_KEY_RECV 0x02 /* key used for recv */
78 #define IEEE80211_KEY_GROUP 0x04 /* key used for WPA group operation */
79 #define IEEE80211_KEY_SWCRYPT 0x10 /* host-based encrypt/decrypt */
80 #define IEEE80211_KEY_SWMIC 0x20 /* host-based enmic/demic */
81 ieee80211_keyix wk_keyix; /* h/w key index */
82 ieee80211_keyix wk_rxkeyix; /* optional h/w rx key index */
83 u_int8_t wk_key[IEEE80211_KEYBUF_SIZE+IEEE80211_MICBUF_SIZE];
84 #define wk_txmic wk_key+IEEE80211_KEYBUF_SIZE+0 /* XXX can't () right */
85 #define wk_rxmic wk_key+IEEE80211_KEYBUF_SIZE+8 /* XXX can't () right */
86 u_int64_t wk_keyrsc; /* key receive sequence counter */
87 u_int64_t wk_keytsc; /* key transmit sequence counter */
88 const struct ieee80211_cipher *wk_cipher;
89 void *wk_private; /* private cipher state */
90 };
91 #define IEEE80211_KEY_COMMON /* common flags passed in by apps */\
92 (IEEE80211_KEY_XMIT | IEEE80211_KEY_RECV | IEEE80211_KEY_GROUP)
93
94 /*
95 * NB: these values are ordered carefully; there are lots of
96 * of implications in any reordering. In particular beware
97 * that 4 is not used to avoid conflicting with IEEE80211_F_PRIVACY.
98 */
99 #define IEEE80211_CIPHER_WEP 0
100 #define IEEE80211_CIPHER_TKIP 1
101 #define IEEE80211_CIPHER_AES_OCB 2
102 #define IEEE80211_CIPHER_AES_CCM 3
103 #define IEEE80211_CIPHER_CKIP 5
104 #define IEEE80211_CIPHER_NONE 6 /* pseudo value */
105
106 #define IEEE80211_CIPHER_MAX (IEEE80211_CIPHER_NONE+1)
107
108 #define IEEE80211_KEYIX_NONE ((ieee80211_keyix) -1)
109 #define IEEE80211_KEY_UNDEFINED(k) ((k).wk_cipher == &ieee80211_cipher_none)
110
111 #if defined(__KERNEL__) || defined(_KERNEL)
112
113 struct ieee80211com;
114 struct ieee80211_node;
115 struct mbuf;
116
117 /*
118 * Crypto state kept in each ieee80211com. Some of this
119 * can/should be shared when virtual AP's are supported.
120 *
121 * XXX save reference to ieee80211com to properly encapsulate state.
122 * XXX split out crypto capabilities from ic_caps
123 */
124 struct ieee80211_crypto_state {
125 struct ieee80211_key cs_nw_keys[IEEE80211_WEP_NKID];
126 ieee80211_keyix cs_def_txkey; /* default/group tx key index */
127 u_int16_t cs_max_keyix; /* max h/w key index */
128
129 int (*cs_key_alloc)(struct ieee80211com *,
130 const struct ieee80211_key *,
131 ieee80211_keyix *, ieee80211_keyix *);
132 int (*cs_key_delete)(struct ieee80211com *,
133 const struct ieee80211_key *);
134 int (*cs_key_set)(struct ieee80211com *,
135 const struct ieee80211_key *,
136 const u_int8_t mac[IEEE80211_ADDR_LEN]);
137 void (*cs_key_update_begin)(struct ieee80211com *);
138 void (*cs_key_update_end)(struct ieee80211com *);
139 };
140
141 void ieee80211_crypto_attach(struct ieee80211com *);
142 void ieee80211_crypto_detach(struct ieee80211com *);
143 int ieee80211_crypto_newkey(struct ieee80211com *,
144 int cipher, int flags, struct ieee80211_key *);
145 int ieee80211_crypto_delkey(struct ieee80211com *,
146 struct ieee80211_key *);
147 int ieee80211_crypto_setkey(struct ieee80211com *,
148 struct ieee80211_key *, const u_int8_t macaddr[IEEE80211_ADDR_LEN]);
149 void ieee80211_crypto_delglobalkeys(struct ieee80211com *);
150
151 /*
152 * Template for a supported cipher. Ciphers register with the
153 * crypto code and are typically loaded as separate modules
154 * (the null cipher is always present).
155 * XXX may need refcnts
156 */
157 struct ieee80211_cipher {
158 const char *ic_name; /* printable name */
159 u_int ic_cipher; /* IEEE80211_CIPHER_* */
160 u_int ic_header; /* size of privacy header (bytes) */
161 u_int ic_trailer; /* size of privacy trailer (bytes) */
162 u_int ic_miclen; /* size of mic trailer (bytes) */
163 void* (*ic_attach)(struct ieee80211com *, struct ieee80211_key *);
164 void (*ic_detach)(struct ieee80211_key *);
165 int (*ic_setkey)(struct ieee80211_key *);
166 int (*ic_encap)(struct ieee80211_key *, struct mbuf *,
167 u_int8_t keyid);
168 int (*ic_decap)(struct ieee80211_key *, struct mbuf *, int);
169 int (*ic_enmic)(struct ieee80211_key *, struct mbuf *, int);
170 int (*ic_demic)(struct ieee80211_key *, struct mbuf *, int);
171 };
172 extern const struct ieee80211_cipher ieee80211_cipher_none;
173 extern const struct ieee80211_cipher ieee80211_cipher_wep;
174 extern const struct ieee80211_cipher ieee80211_cipher_tkip;
175 extern const struct ieee80211_cipher ieee80211_cipher_ccmp;
176
177 void ieee80211_crypto_register(const struct ieee80211_cipher *);
178 void ieee80211_crypto_unregister(const struct ieee80211_cipher *);
179 int ieee80211_crypto_available(u_int cipher);
180
181 struct ieee80211_key *ieee80211_crypto_encap(struct ieee80211com *,
182 struct ieee80211_node *, struct mbuf *);
183 struct ieee80211_key *ieee80211_crypto_decap(struct ieee80211com *,
184 struct ieee80211_node *, struct mbuf **, int);
185
186 /*
187 * Check and remove any MIC.
188 */
189 static __inline int
ieee80211_crypto_demic(struct ieee80211com * ic,struct ieee80211_key * k,struct mbuf * m,int force)190 ieee80211_crypto_demic(struct ieee80211com *ic,
191 struct ieee80211_key *k, struct mbuf *m, int force)
192 {
193 const struct ieee80211_cipher *cip = k->wk_cipher;
194 return (cip->ic_miclen > 0 ? cip->ic_demic(k, m, force) : 1);
195 }
196
197 /*
198 * Add any MIC.
199 */
200 static __inline int
ieee80211_crypto_enmic(struct ieee80211com * ic,struct ieee80211_key * k,struct mbuf * m,int force)201 ieee80211_crypto_enmic(struct ieee80211com *ic,
202 struct ieee80211_key *k, struct mbuf *m, int force)
203 {
204 const struct ieee80211_cipher *cip = k->wk_cipher;
205 return (cip->ic_miclen > 0 ? cip->ic_enmic(k, m, force) : 1);
206 }
207
208 /*
209 * Reset key state to an unused state. The crypto
210 * key allocation mechanism insures other state (e.g.
211 * key data) is properly setup before a key is used.
212 */
213 static __inline void
ieee80211_crypto_resetkey(struct ieee80211com * ic,struct ieee80211_key * k,ieee80211_keyix ix)214 ieee80211_crypto_resetkey(struct ieee80211com *ic,
215 struct ieee80211_key *k, ieee80211_keyix ix)
216 {
217 k->wk_cipher = &ieee80211_cipher_none;
218 k->wk_private = k->wk_cipher->ic_attach(ic, k);
219 k->wk_keyix = k->wk_rxkeyix = ix;
220 k->wk_flags = IEEE80211_KEY_XMIT | IEEE80211_KEY_RECV;
221 }
222
223 /*
224 * Crypt-related notification methods.
225 */
226 void ieee80211_notify_replay_failure(struct ieee80211com *,
227 const struct ieee80211_frame *, const struct ieee80211_key *,
228 u_int64_t rsc);
229 void ieee80211_notify_michael_failure(struct ieee80211com *,
230 const struct ieee80211_frame *, u_int keyix);
231 #endif /* defined(__KERNEL__) || defined(_KERNEL) */
232 #endif /* !_NET80211_IEEE80211_CRYPTO_H_ */
233