sys/netproto/802_11/ieee80211_crypto.h

   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: src/sys/net80211/ieee80211_crypto.h,v 1.9.2.1 2005/09/03 22:40:02 sam Exp $
  33  * $DragonFly: src/sys/netproto/802_11/ieee80211_crypto.h,v 1.4 2007/05/07 14:12:16 sephe 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         uint8_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 uint16_t ieee80211_keyix;       /* h/w key index */
  71
  72 struct ieee80211_key {
  73         uint8_t         wk_keylen;      /* key length in bytes */
  74         uint8_t         wk_keyid;       /* key id */
  75         uint16_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 #define IEEE80211_KEY_NOHDR     0x40    /* driver appends crypto header */
  82 #define IEEE80211_KEY_NOMIC     0x80    /* driver strips TKIP MIC */
  83         ieee80211_keyix wk_keyix;       /* h/w key index */
  84         ieee80211_keyix wk_rxkeyix;     /* optional h/w rx key index */
  85         uint8_t         wk_key[IEEE80211_KEYBUF_SIZE+IEEE80211_MICBUF_SIZE];
  86 #define wk_txmic        wk_key+IEEE80211_KEYBUF_SIZE+0  /* XXX can't () right */
  87 #define wk_rxmic        wk_key+IEEE80211_KEYBUF_SIZE+8  /* XXX can't () right */
  88         uint64_t        wk_keyrsc;      /* key receive sequence counter */
  89         uint64_t        wk_keytsc;      /* key transmit sequence counter */
  90         const struct ieee80211_cipher *wk_cipher;
  91         void            *wk_private;    /* private cipher state */
  92 };
  93 #define IEEE80211_KEY_COMMON            /* common flags passed in by apps */\
  94         (IEEE80211_KEY_XMIT | IEEE80211_KEY_RECV | IEEE80211_KEY_GROUP)
  95
  96 /*
  97  * NB: these values are ordered carefully; there are lots of
  98  * of implications in any reordering.  In particular beware
  99  * that 4 is not used to avoid conflicting with IEEE80211_F_PRIVACY.
 100  */
 101 #define IEEE80211_CIPHER_WEP            0
 102 #define IEEE80211_CIPHER_TKIP           1
 103 #define IEEE80211_CIPHER_AES_OCB        2
 104 #define IEEE80211_CIPHER_AES_CCM        3
 105 #define IEEE80211_CIPHER_CKIP           5
 106 #define IEEE80211_CIPHER_NONE           6       /* pseudo value */
 107
 108 #define IEEE80211_CIPHER_MAX            (IEEE80211_CIPHER_NONE+1)
 109
 110 #define IEEE80211_KEYIX_NONE    ((ieee80211_keyix) -1)
 111
 112 #if defined(__KERNEL__) || defined(_KERNEL)
 113
 114 struct ieee80211com;
 115 struct ieee80211_node;
 116 struct mbuf;
 117
 118 /*
 119  * Crypto state kept in each ieee80211com.  Some of this
 120  * can/should be shared when virtual AP's are supported.
 121  *
 122  * XXX save reference to ieee80211com to properly encapsulate state.
 123  * XXX split out crypto capabilities from ic_caps
 124  */
 125 struct ieee80211_crypto_state {
 126         struct ieee80211_key    cs_nw_keys[IEEE80211_WEP_NKID];
 127         ieee80211_keyix         cs_def_txkey;   /* default/group tx key index */
 128         uint16_t                cs_max_keyix;   /* max h/w key index */
 129
 130         int                     (*cs_key_alloc)(struct ieee80211com *,
 131                                         const struct ieee80211_key *,
 132                                         ieee80211_keyix *, ieee80211_keyix *);
 133         int                     (*cs_key_delete)(struct ieee80211com *,
 134                                         const struct ieee80211_key *);
 135         int                     (*cs_key_set)(struct ieee80211com *,
 136                                         const struct ieee80211_key *,
 137                                         const uint8_t mac[IEEE80211_ADDR_LEN]);
 138         void                    (*cs_key_update_begin)(struct ieee80211com *);
 139         void                    (*cs_key_update_end)(struct ieee80211com *);
 140 };
 141
 142 void    ieee80211_crypto_attach(struct ieee80211com *);
 143 void    ieee80211_crypto_detach(struct ieee80211com *);
 144 int     ieee80211_crypto_newkey(struct ieee80211com *,
 145                 int cipher, int flags, struct ieee80211_key *);
 146 int     ieee80211_crypto_delkey(struct ieee80211com *,
 147                 struct ieee80211_key *);
 148 int     ieee80211_crypto_setkey(struct ieee80211com *,
 149                 struct ieee80211_key *, const uint8_t macaddr[IEEE80211_ADDR_LEN]);
 150 void    ieee80211_crypto_delglobalkeys(struct ieee80211com *);
 151
 152 struct ieee80211_crypto_iv {
 153         /*
 154          * Keep this layout!
 155          * Crypto modules will assume that ic_iv and ic_eiv are contiguous.
 156          */
 157         uint8_t ic_iv[4];
 158         uint8_t ic_eiv[4];
 159 };
 160
 161 /*
 162  * Template for a supported cipher.  Ciphers register with the
 163  * crypto code and are typically loaded as separate modules
 164  * (the null cipher is always present).
 165  * XXX may need refcnts
 166  */
 167 struct ieee80211_cipher {
 168         const char *ic_name;            /* printable name */
 169         u_int   ic_cipher;              /* IEEE80211_CIPHER_* */
 170         u_int   ic_header;              /* size of privacy header (bytes) */
 171         u_int   ic_trailer;             /* size of privacy trailer (bytes) */
 172         u_int   ic_miclen;              /* size of mic trailer (bytes) */
 173         void*   (*ic_attach)(struct ieee80211com *, struct ieee80211_key *);
 174         void    (*ic_detach)(struct ieee80211_key *);
 175         int     (*ic_setkey)(struct ieee80211_key *);
 176         int     (*ic_encap)(struct ieee80211_key *, struct mbuf *,
 177                         uint8_t keyid);
 178         int     (*ic_decap)(struct ieee80211_key *, struct mbuf *, int);
 179         int     (*ic_enmic)(struct ieee80211_key *, struct mbuf *, int);
 180         int     (*ic_demic)(struct ieee80211_key *, struct mbuf *, int);
 181         int     (*ic_getiv)(struct ieee80211_key *,
 182                         struct ieee80211_crypto_iv *, uint8_t);
 183         int     (*ic_update)(struct ieee80211_key *,
 184                         const struct ieee80211_crypto_iv *,
 185                         const struct ieee80211_frame *);
 186 };
 187 extern  const struct ieee80211_cipher ieee80211_cipher_none;
 188
 189 void    ieee80211_crypto_register(const struct ieee80211_cipher *);
 190 void    ieee80211_crypto_unregister(const struct ieee80211_cipher *);
 191 int     ieee80211_crypto_available(u_int cipher);
 192 const struct ieee80211_cipher *ieee80211_crypto_cipher(u_int cipher);
 193
 194 void    ieee80211_crypto_resetkey(struct ieee80211com *,
 195                 struct ieee80211_key *, ieee80211_keyix);
 196
 197 struct ieee80211_key *ieee80211_crypto_encap(struct ieee80211com *,
 198                 struct ieee80211_node *, struct mbuf *);
 199 struct ieee80211_key *ieee80211_crypto_decap(struct ieee80211com *,
 200                 struct ieee80211_node *, struct mbuf *, int);
 201 struct ieee80211_key *ieee80211_crypto_findkey(struct ieee80211com *,
 202                 struct ieee80211_node *, struct mbuf *);
 203 struct ieee80211_key *ieee80211_crypto_encap_withkey(struct ieee80211com *,
 204                 struct mbuf *, struct ieee80211_key *);
 205
 206 struct ieee80211_key *ieee80211_crypto_update(struct ieee80211com *,
 207                 struct ieee80211_node *, const struct ieee80211_crypto_iv *,
 208                 const struct ieee80211_frame *);
 209 struct ieee80211_key *ieee80211_crypto_getiv(struct ieee80211com *,
 210                 struct ieee80211_crypto_iv *, struct ieee80211_key *);
 211
 212 /*
 213  * Check and remove any MIC.
 214  */
 215 static __inline int
 216 ieee80211_crypto_demic(struct ieee80211com *ic, struct ieee80211_key *k,
 217         struct mbuf *m, int force)
 218 {
 219         const struct ieee80211_cipher *cip = k->wk_cipher;
 220         return (cip->ic_miclen > 0 ? cip->ic_demic(k, m, force) : 1);
 221 }
 222
 223 /*
 224  * Add any MIC.
 225  */
 226 static __inline int
 227 ieee80211_crypto_enmic(struct ieee80211com *ic,
 228         struct ieee80211_key *k, struct mbuf *m, int force)
 229 {
 230         const struct ieee80211_cipher *cip = k->wk_cipher;
 231         return (cip->ic_miclen > 0 ? cip->ic_enmic(k, m, force) : 1);
 232 }
 233
 234 /*
 235  * Crypt-related notification methods.
 236  */
 237 void    ieee80211_notify_replay_failure(struct ieee80211com *,
 238                 const struct ieee80211_frame *, const struct ieee80211_key *,
 239                 uint64_t rsc);
 240 void    ieee80211_notify_michael_failure(struct ieee80211com *,
 241                 const struct ieee80211_frame *, u_int keyix);
 242
 243 #endif /* defined(__KERNEL__) || defined(_KERNEL) */
 244 #endif /* _NET80211_IEEE80211_CRYPTO_H_ */