xref: /freebsd/sys/net80211/ieee80211_crypto.h (revision 77b1e4f32f31b219c238c81b726d079a003b465c)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2001 Atsushi Onoe
5  * Copyright (c) 2002-2008 Sam Leffler, Errno Consulting
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 #ifndef _NET80211_IEEE80211_CRYPTO_H_
29 #define _NET80211_IEEE80211_CRYPTO_H_
30 
31 /*
32  * 802.11 protocol crypto-related definitions.
33  */
34 #define	IEEE80211_KEYBUF_SIZE	16
35 #define	IEEE80211_MICBUF_SIZE	(8+8)	/* space for both tx+rx keys */
36 
37 /*
38  * Old WEP-style key.  Deprecated.
39  */
40 struct ieee80211_wepkey {
41 	u_int		wk_len;		/* key length in bytes */
42 	uint8_t		wk_key[IEEE80211_KEYBUF_SIZE];
43 };
44 
45 struct ieee80211_rsnparms {
46 	uint8_t		rsn_mcastcipher;	/* mcast/group cipher */
47 	uint8_t		rsn_mcastkeylen;	/* mcast key length */
48 	uint8_t		rsn_ucastcipher;	/* selected unicast cipher */
49 	uint8_t		rsn_ucastkeylen;	/* unicast key length */
50 	uint8_t		rsn_keymgmt;		/* selected key mgmt algo */
51 	uint16_t	rsn_caps;		/* capabilities */
52 };
53 
54 struct ieee80211_cipher;
55 
56 /*
57  * Crypto key state.  There is sufficient room for all supported
58  * ciphers (see below).  The underlying ciphers are handled
59  * separately through loadable cipher modules that register with
60  * the generic crypto support.  A key has a reference to an instance
61  * of the cipher; any per-key state is hung off wk_private by the
62  * cipher when it is attached.  Ciphers are automatically called
63  * to detach and cleanup any such state when the key is deleted.
64  *
65  * The generic crypto support handles encap/decap of cipher-related
66  * frame contents for both hardware- and software-based implementations.
67  * A key requiring software crypto support is automatically flagged and
68  * the cipher is expected to honor this and do the necessary work.
69  * Ciphers such as TKIP may also support mixed hardware/software
70  * encrypt/decrypt and MIC processing.
71  */
72 typedef uint16_t ieee80211_keyix;	/* h/w key index */
73 
74 struct ieee80211_key {
75 	uint8_t		wk_keylen;	/* key length in bytes */
76 	uint8_t		wk_pad;		/* .. some drivers use this. Fix that. */
77 	uint8_t		wk_pad1[2];
78 	uint32_t	wk_flags;
79 #define	IEEE80211_KEY_XMIT	0x00000001	/* key used for xmit */
80 #define	IEEE80211_KEY_RECV	0x00000002	/* key used for recv */
81 #define	IEEE80211_KEY_GROUP	0x00000004	/* key used for WPA group operation */
82 #define	IEEE80211_KEY_NOREPLAY	0x00000008	/* ignore replay failures */
83 #define	IEEE80211_KEY_SWENCRYPT	0x00000010	/* host-based encrypt */
84 #define	IEEE80211_KEY_SWDECRYPT	0x00000020	/* host-based decrypt */
85 #define	IEEE80211_KEY_SWENMIC	0x00000040	/* host-based enmic */
86 #define	IEEE80211_KEY_SWDEMIC	0x00000080	/* host-based demic */
87 #define	IEEE80211_KEY_DEVKEY	0x00000100	/* device key request completed */
88 #define	IEEE80211_KEY_CIPHER0	0x00001000	/* cipher-specific action 0 */
89 #define	IEEE80211_KEY_CIPHER1	0x00002000	/* cipher-specific action 1 */
90 #define	IEEE80211_KEY_NOIV	0x00004000	/* don't insert IV/MIC for !mgmt */
91 #define	IEEE80211_KEY_NOIVMGT	0x00008000	/* don't insert IV/MIC for mgmt */
92 #define	IEEE80211_KEY_NOMIC	0x00010000	/* don't insert MIC for !mgmt */
93 #define	IEEE80211_KEY_NOMICMGT	0x00020000	/* don't insert MIC for mgmt */
94 
95 	ieee80211_keyix	wk_keyix;	/* h/w key index */
96 	ieee80211_keyix	wk_rxkeyix;	/* optional h/w rx key index */
97 	/* TODO: deprecate direct access to wk_key, wk_txmic, wk_rxmic */
98 	uint8_t		wk_key[IEEE80211_KEYBUF_SIZE+IEEE80211_MICBUF_SIZE];
99 #define	wk_txmic	wk_key+IEEE80211_KEYBUF_SIZE+0	/* XXX can't () right */
100 #define	wk_rxmic	wk_key+IEEE80211_KEYBUF_SIZE+8	/* XXX can't () right */
101 					/* key receive sequence counter */
102 	uint64_t	wk_keyrsc[IEEE80211_TID_SIZE];
103 	uint64_t	wk_keytsc;	/* key transmit sequence counter */
104 	const struct ieee80211_cipher *wk_cipher;
105 	void		*wk_private;	/* private cipher state */
106 	uint8_t		wk_macaddr[IEEE80211_ADDR_LEN];
107 };
108 #define	IEEE80211_KEY_COMMON 		/* common flags passed in by apps */\
109 	(IEEE80211_KEY_XMIT | IEEE80211_KEY_RECV | IEEE80211_KEY_GROUP | \
110 	 IEEE80211_KEY_NOREPLAY)
111 
112 #define	IEEE80211_KEY_SWCRYPT \
113 	(IEEE80211_KEY_SWENCRYPT | IEEE80211_KEY_SWDECRYPT)
114 #define	IEEE80211_KEY_SWMIC	(IEEE80211_KEY_SWENMIC | IEEE80211_KEY_SWDEMIC)
115 
116 #define IEEE80211_KEY_DEVICE		/* flags owned by device driver */\
117 	(IEEE80211_KEY_DEVKEY|IEEE80211_KEY_CIPHER0|IEEE80211_KEY_CIPHER1| \
118 	 IEEE80211_KEY_SWCRYPT|IEEE80211_KEY_SWMIC|IEEE80211_KEY_NOIV | \
119 	 IEEE80211_KEY_NOIVMGT|IEEE80211_KEY_NOMIC|IEEE80211_KEY_NOMICMGT)
120 
121 #define	IEEE80211_KEY_BITS \
122 	"\20\1XMIT\2RECV\3GROUP\4NOREPLAY\5SWENCRYPT\6SWDECRYPT\7SWENMIC\10SWDEMIC" \
123 	"\11DEVKEY\12CIPHER0\13CIPHER1\14NOIV\15NOIVMGT\16NOMIC\17NOMICMGT"
124 
125 #define	IEEE80211_KEYIX_NONE	((ieee80211_keyix) -1)
126 
127 /*
128  * NB: these values are ordered carefully; there are lots of
129  * of implications in any reordering.  Beware that 4 is used
130  * only to indicate h/w TKIP MIC support in driver capabilities;
131  * there is no separate cipher support (it's rolled into the
132  * TKIP cipher support).
133  */
134 #define	IEEE80211_CIPHER_WEP		0
135 #define	IEEE80211_CIPHER_TKIP		1
136 #define	IEEE80211_CIPHER_AES_OCB	2
137 #define	IEEE80211_CIPHER_AES_CCM	3
138 #define	IEEE80211_CIPHER_TKIPMIC	4	/* TKIP MIC capability */
139 #define	IEEE80211_CIPHER_CKIP		5
140 #define	IEEE80211_CIPHER_NONE		6	/* pseudo value */
141 #define	IEEE80211_CIPHER_AES_CCM_256	7
142 #define	IEEE80211_CIPHER_BIP_CMAC_128	8
143 #define	IEEE80211_CIPHER_BIP_CMAC_256	9
144 #define	IEEE80211_CIPHER_BIP_GMAC_128	10
145 #define	IEEE80211_CIPHER_BIP_GMAC_256	11
146 #define	IEEE80211_CIPHER_AES_GCM_128	12
147 #define	IEEE80211_CIPHER_AES_GCM_256	13
148 
149 #define	IEEE80211_CIPHER_LAST		13
150 
151 #define	IEEE80211_CIPHER_MAX		(IEEE80211_CIPHER_LAST+1)
152 
153 /* capability bits in ic_cryptocaps/iv_cryptocaps */
154 #define	IEEE80211_CRYPTO_WEP		(1<<IEEE80211_CIPHER_WEP)
155 #define	IEEE80211_CRYPTO_TKIP		(1<<IEEE80211_CIPHER_TKIP)
156 #define	IEEE80211_CRYPTO_AES_OCB	(1<<IEEE80211_CIPHER_AES_OCB)
157 #define	IEEE80211_CRYPTO_AES_CCM	(1<<IEEE80211_CIPHER_AES_CCM)
158 #define	IEEE80211_CRYPTO_TKIPMIC	(1<<IEEE80211_CIPHER_TKIPMIC)
159 #define	IEEE80211_CRYPTO_CKIP		(1<<IEEE80211_CIPHER_CKIP)
160 #define	IEEE80211_CRYPTO_AES_CCM_256	(1<<IEEE80211_CIPHER_AES_CCM_256)
161 #define	IEEE80211_CRYPTO_BIP_CMAC_128	(1<<IEEE80211_CIPHER_BIP_CMAC_128)
162 #define	IEEE80211_CRYPTO_BIP_CMAC_256	(1<<IEEE80211_CIPHER_BIP_CMAC_256)
163 #define	IEEE80211_CRYPTO_BIP_GMAC_128	(1<<IEEE80211_CIPHER_BIP_GMAC_128)
164 #define	IEEE80211_CRYPTO_BIP_GMAC_256	(1<<IEEE80211_CIPHER_BIP_GMAC_256)
165 #define	IEEE80211_CRYPTO_AES_GCM_128	(1<<IEEE80211_CIPHER_AES_GCM_128)
166 #define	IEEE80211_CRYPTO_AES_GCM_256	(1<<IEEE80211_CIPHER_AES_GCM_256)
167 
168 #define	IEEE80211_CRYPTO_BITS \
169 	"\20\1WEP\2TKIP\3AES\4AES_CCM\5TKIPMIC\6CKIP\10AES_CCM_256" \
170 	"\11BIP_CMAC_128\12BIP_CMAC_256\13BIP_GMAC_128\14BIP_CMAC_256" \
171 	"\15AES_GCM_128\16AES_GCM_256"
172 
173 #if defined(__KERNEL__) || defined(_KERNEL)
174 
175 struct ieee80211com;
176 struct ieee80211vap;
177 struct ieee80211_node;
178 struct mbuf;
179 
180 MALLOC_DECLARE(M_80211_CRYPTO);
181 
182 void	ieee80211_crypto_attach(struct ieee80211com *);
183 void	ieee80211_crypto_detach(struct ieee80211com *);
184 void	ieee80211_crypto_set_supported_software_ciphers(struct ieee80211com *,
185 	    uint32_t cipher_set);
186 void	ieee80211_crypto_set_supported_hardware_ciphers(struct ieee80211com *,
187 	    uint32_t cipher_set);
188 void	ieee80211_crypto_set_supported_driver_keymgmt(struct ieee80211com *,
189 	    uint32_t keymgmt_set);
190 void	ieee80211_crypto_vattach(struct ieee80211vap *);
191 void	ieee80211_crypto_vdetach(struct ieee80211vap *);
192 int	ieee80211_crypto_newkey(struct ieee80211vap *,
193 		int cipher, int flags, struct ieee80211_key *);
194 int	ieee80211_crypto_delkey(struct ieee80211vap *,
195 		struct ieee80211_key *);
196 int	ieee80211_crypto_setkey(struct ieee80211vap *, struct ieee80211_key *);
197 void	ieee80211_crypto_delglobalkeys(struct ieee80211vap *);
198 void	ieee80211_crypto_reload_keys(struct ieee80211com *);
199 void	ieee80211_crypto_set_deftxkey(struct ieee80211vap *,
200 	    ieee80211_keyix kid);
201 
202 /*
203  * Template for a supported cipher.  Ciphers register with the
204  * crypto code and are typically loaded as separate modules
205  * (the null cipher is always present).
206  * XXX may need refcnts
207  */
208 struct ieee80211_cipher {
209 	const char *ic_name;		/* printable name */
210 	u_int	ic_cipher;		/* IEEE80211_CIPHER_* */
211 	u_int	ic_header;		/* size of privacy header (bytes) */
212 	u_int	ic_trailer;		/* size of privacy trailer (bytes) */
213 	u_int	ic_miclen;		/* size of mic trailer (bytes) */
214 	void*	(*ic_attach)(struct ieee80211vap *, struct ieee80211_key *);
215 	void	(*ic_detach)(struct ieee80211_key *);
216 	int	(*ic_setkey)(struct ieee80211_key *);
217 	void	(*ic_setiv)(struct ieee80211_key *, uint8_t *);
218 	int	(*ic_encap)(struct ieee80211_key *, struct mbuf *);
219 	int	(*ic_decap)(struct ieee80211_key *, struct mbuf *, int);
220 	/*
221 	 * ic_enmic() and ic_demic() are currently only used by TKIP.
222 	 * Please see ieee80211_crypto_enmic() and ieee80211_crypto_demic()
223 	 * for more information.
224 	 */
225 	int	(*ic_enmic)(struct ieee80211_key *, struct mbuf *, int);
226 	int	(*ic_demic)(struct ieee80211_key *, struct mbuf *, int);
227 };
228 extern	const struct ieee80211_cipher ieee80211_cipher_none;
229 
230 #define	IEEE80211_KEY_UNDEFINED(k) \
231 	((k)->wk_cipher == &ieee80211_cipher_none)
232 
233 void	ieee80211_crypto_register(const struct ieee80211_cipher *);
234 void	ieee80211_crypto_unregister(const struct ieee80211_cipher *);
235 int	ieee80211_crypto_available(u_int cipher);
236 
237 int	ieee80211_crypto_get_key_wepidx(const struct ieee80211vap *,
238 	    const struct ieee80211_key *k);
239 uint8_t	ieee80211_crypto_get_keyid(struct ieee80211vap *vap,
240 		struct ieee80211_key *k);
241 struct ieee80211_key *ieee80211_crypto_get_txkey(struct ieee80211_node *,
242 		struct mbuf *);
243 struct ieee80211_key *ieee80211_crypto_encap(struct ieee80211_node *,
244 		struct mbuf *);
245 int	ieee80211_crypto_decap(struct ieee80211_node *,
246 		struct mbuf *, int, struct ieee80211_key **);
247 int ieee80211_crypto_demic(struct ieee80211vap *vap, struct ieee80211_key *k,
248 		struct mbuf *, int);
249 /**
250  * @brief Add any pre-fragmentation MIC to an MSDU.
251  *
252  * This is called before 802.11 fragmentation.  Crypto types that implement
253  * a MIC/ICV check per MSDU will not implement this function.
254  *
255  * As an example, TKIP implements a Michael MIC check over the entire
256  * unencrypted MSDU before fragmenting it into MPDUs and passing each
257  * MPDU to be separately encrypted with their own MIC/ICV.
258  *
259  * Please see 802.11-2020 12.5.2.1.2 (TKIP cryptographic encapsulation)
260  * for more information.
261  *
262  * @param vap	the current VAP
263  * @param k	the current key
264  * @param m	the mbuf representing the MSDU
265  * @param f	set to 1 to force a MSDU MIC check, even if HW encrypted
266  * @returns	0 if error / MIC encap failed, 1 if OK
267  */
268 static __inline int
ieee80211_crypto_enmic(struct ieee80211vap * vap,struct ieee80211_key * k,struct mbuf * m,int force)269 ieee80211_crypto_enmic(struct ieee80211vap *vap,
270 	struct ieee80211_key *k, struct mbuf *m, int force)
271 {
272 	const struct ieee80211_cipher *cip = k->wk_cipher;
273 	return (cip->ic_miclen > 0 ? cip->ic_enmic(k, m, force) : 1);
274 }
275 
276 /*
277  * Reset key state to an unused state.  The crypto
278  * key allocation mechanism insures other state (e.g.
279  * key data) is properly setup before a key is used.
280  */
281 static __inline void
ieee80211_crypto_resetkey(struct ieee80211vap * vap,struct ieee80211_key * k,ieee80211_keyix ix)282 ieee80211_crypto_resetkey(struct ieee80211vap *vap,
283 	struct ieee80211_key *k, ieee80211_keyix ix)
284 {
285 	k->wk_cipher = &ieee80211_cipher_none;
286 	k->wk_private = k->wk_cipher->ic_attach(vap, k);
287 	k->wk_keyix = k->wk_rxkeyix = ix;
288 	k->wk_flags = IEEE80211_KEY_XMIT | IEEE80211_KEY_RECV;
289 }
290 
291 /*
292  * Crypt-related notification methods.
293  */
294 void	ieee80211_notify_replay_failure(struct ieee80211vap *,
295 		const struct ieee80211_frame *, const struct ieee80211_key *,
296 		uint64_t rsc, int tid);
297 void	ieee80211_notify_michael_failure(struct ieee80211vap *,
298 		const struct ieee80211_frame *, ieee80211_keyix keyix);
299 
300 /* AAD assembly for CCMP/GCMP. */
301 uint16_t	ieee80211_crypto_init_aad(const struct ieee80211_frame *,
302 		uint8_t *, int);
303 
304 /**
305  * @brief Return the key data.
306  *
307  * This returns a pointer to the key data.  Note it does not
308  * guarantee the TX/RX MIC will be immediately after the key.
309  * Callers must use ieee80211_crypto_get_key_txmic_data()
310  * and ieee80211_crypto_get_key_rxmic_data() for that.
311  *
312  * Note: there's no locking; this needs to be called in
313  * a situation where the ieee80211_key won't disappear.
314  *
315  * @param k ieee80211_key
316  * @returns NULL if no key data is available, or a pointer
317  *  to the key data.
318  */
319 static inline const uint8_t *
ieee80211_crypto_get_key_data(const struct ieee80211_key * k)320 ieee80211_crypto_get_key_data(const struct ieee80211_key *k)
321 {
322 	return (k->wk_key);
323 }
324 
325 /**
326  * @brief Return the key length in bytes.
327  *
328  * This doesn't include any TX/RX MIC (eg from TKIP).
329  *
330  * Note: there's no locking; this needs to be called in
331  * a situation where the ieee80211_key won't disappear.
332  *
333  * @param k ieee80211_key
334  * @returns the key length (without any MIC) in bytes
335  */
336 static inline const uint16_t
ieee80211_crypto_get_key_len(const struct ieee80211_key * k)337 ieee80211_crypto_get_key_len(const struct ieee80211_key *k)
338 {
339 	return (k->wk_keylen);
340 }
341 
342 /**
343  * @brief Return the TX MIC data.
344  *
345  * This returns a pointer to the TX MIC data.
346  *
347  * Note: there's no locking; this needs to be called in
348  * a situation where the ieee80211_key won't disappear.
349  *
350  * @param k ieee80211_key
351  * @returns NULL if no key data is available, or a pointer
352  *  to the TX MIC data.
353  */
354 static inline const uint8_t *
ieee80211_crypto_get_key_txmic_data(const struct ieee80211_key * k)355 ieee80211_crypto_get_key_txmic_data(const struct ieee80211_key *k)
356 {
357 	return (k->wk_txmic);
358 }
359 
360 /**
361  * @brief Return the TX MIC length in bytes.
362  *
363  * Note: there's no locking; this needs to be called in
364  * a situation where the ieee80211_key won't disappear.
365  *
366  * @param k ieee80211_key
367  * @returns the TX MIC length in bytes
368  */
369 static inline const uint16_t
ieee80211_crypto_get_key_txmic_len(const struct ieee80211_key * k)370 ieee80211_crypto_get_key_txmic_len(const struct ieee80211_key *k)
371 {
372 	return (k->wk_cipher->ic_miclen);
373 }
374 
375 /**
376  * @brief Return the RX MIC data.
377  *
378  * This returns a pointer to the RX MIC data.
379  *
380  * Note: there's no locking; this needs to be called in
381  * a situation where the ieee80211_key won't disappear.
382  *
383  * @param k ieee80211_key
384  * @returns NULL if no key data is available, or a pointer
385  *  to the RX MIC data.
386  */
387 static inline const uint8_t *
ieee80211_crypto_get_key_rxmic_data(const struct ieee80211_key * k)388 ieee80211_crypto_get_key_rxmic_data(const struct ieee80211_key *k)
389 {
390 	return (k->wk_rxmic);
391 }
392 
393 /**
394  * @brief Return the RX MIC length in bytes.
395  *
396  * Note: there's no locking; this needs to be called in
397  * a situation where the ieee80211_key won't disappear.
398  *
399  * @param k ieee80211_key
400  * @returns the RX MIC length in bytes
401  */
402 static inline const uint16_t
ieee80211_crypto_get_key_rxmic_len(const struct ieee80211_key * k)403 ieee80211_crypto_get_key_rxmic_len(const struct ieee80211_key *k)
404 {
405 	return (k->wk_cipher->ic_miclen);
406 }
407 
408 #endif /* defined(__KERNEL__) || defined(_KERNEL) */
409 #endif /* _NET80211_IEEE80211_CRYPTO_H_ */
410