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sys/net80211/ieee80211_crypto.c

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  1 /*-
  2  * Copyright (c) 2001 Atsushi Onoe
  3  * Copyright (c) 2002-2008 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  *
 15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 25  */
 26 
 27 #include <sys/cdefs.h>
 28 __FBSDID("$FreeBSD: src/sys/net80211/ieee80211_crypto.c,v 1.21 2008/10/25 23:23:41 sam Exp $");
 29 
 30 /*
 31  * IEEE 802.11 generic crypto support.
 32  */
 33 #include "opt_wlan.h"
 34 
 35 #include <sys/param.h>
 36 #include <sys/kernel.h>
 37 #include <sys/malloc.h>
 38 #include <sys/mbuf.h>   
 39 
 40 #include <sys/socket.h>
 41 
 42 #include <net/if.h>
 43 #include <net/if_media.h>
 44 #include <net/ethernet.h>               /* XXX ETHER_HDR_LEN */
 45 
 46 #include <net80211/ieee80211_var.h>
 47 
 48 MALLOC_DEFINE(M_80211_CRYPTO, "80211crypto", "802.11 crypto state");
 49 
 50 static  int _ieee80211_crypto_delkey(struct ieee80211vap *,
 51                 struct ieee80211_key *);
 52 
 53 /*
 54  * Table of registered cipher modules.
 55  */
 56 static  const struct ieee80211_cipher *ciphers[IEEE80211_CIPHER_MAX];
 57 
 58 /*
 59  * Default "null" key management routines.
 60  */
 61 static int
 62 null_key_alloc(struct ieee80211vap *vap, struct ieee80211_key *k,
 63         ieee80211_keyix *keyix, ieee80211_keyix *rxkeyix)
 64 {
 65         if (!(&vap->iv_nw_keys[0] <= k &&
 66              k < &vap->iv_nw_keys[IEEE80211_WEP_NKID])) {
 67                 /*
 68                  * Not in the global key table, the driver should handle this
 69                  * by allocating a slot in the h/w key table/cache.  In
 70                  * lieu of that return key slot 0 for any unicast key
 71                  * request.  We disallow the request if this is a group key.
 72                  * This default policy does the right thing for legacy hardware
 73                  * with a 4 key table.  It also handles devices that pass
 74                  * packets through untouched when marked with the WEP bit
 75                  * and key index 0.
 76                  */
 77                 if (k->wk_flags & IEEE80211_KEY_GROUP)
 78                         return 0;
 79                 *keyix = 0;     /* NB: use key index 0 for ucast key */
 80         } else {
 81                 *keyix = k - vap->iv_nw_keys;
 82         }
 83         *rxkeyix = IEEE80211_KEYIX_NONE;        /* XXX maybe *keyix? */
 84         return 1;
 85 }
 86 static int
 87 null_key_delete(struct ieee80211vap *vap, const struct ieee80211_key *k)
 88 {
 89         return 1;
 90 }
 91 static  int
 92 null_key_set(struct ieee80211vap *vap, const struct ieee80211_key *k,
 93         const uint8_t mac[IEEE80211_ADDR_LEN])
 94 {
 95         return 1;
 96 }
 97 static void null_key_update(struct ieee80211vap *vap) {}
 98 
 99 /*
100  * Write-arounds for common operations.
101  */
102 static __inline void
103 cipher_detach(struct ieee80211_key *key)
104 {
105         key->wk_cipher->ic_detach(key);
106 }
107 
108 static __inline void *
109 cipher_attach(struct ieee80211vap *vap, struct ieee80211_key *key)
110 {
111         return key->wk_cipher->ic_attach(vap, key);
112 }
113 
114 /* 
115  * Wrappers for driver key management methods.
116  */
117 static __inline int
118 dev_key_alloc(struct ieee80211vap *vap,
119         struct ieee80211_key *key,
120         ieee80211_keyix *keyix, ieee80211_keyix *rxkeyix)
121 {
122         return vap->iv_key_alloc(vap, key, keyix, rxkeyix);
123 }
124 
125 static __inline int
126 dev_key_delete(struct ieee80211vap *vap,
127         const struct ieee80211_key *key)
128 {
129         return vap->iv_key_delete(vap, key);
130 }
131 
132 static __inline int
133 dev_key_set(struct ieee80211vap *vap, const struct ieee80211_key *key)
134 {
135         return vap->iv_key_set(vap, key, key->wk_macaddr);
136 }
137 
138 /*
139  * Setup crypto support for a device/shared instance.
140  */
141 void
142 ieee80211_crypto_attach(struct ieee80211com *ic)
143 {
144         /* NB: we assume everything is pre-zero'd */
145         ciphers[IEEE80211_CIPHER_NONE] = &ieee80211_cipher_none;
146 }
147 
148 /*
149  * Teardown crypto support.
150  */
151 void
152 ieee80211_crypto_detach(struct ieee80211com *ic)
153 {
154 }
155 
156 /*
157  * Setup crypto support for a vap.
158  */
159 void
160 ieee80211_crypto_vattach(struct ieee80211vap *vap)
161 {
162         int i;
163 
164         /* NB: we assume everything is pre-zero'd */
165         vap->iv_max_keyix = IEEE80211_WEP_NKID;
166         vap->iv_def_txkey = IEEE80211_KEYIX_NONE;
167         for (i = 0; i < IEEE80211_WEP_NKID; i++)
168                 ieee80211_crypto_resetkey(vap, &vap->iv_nw_keys[i],
169                         IEEE80211_KEYIX_NONE);
170         /*
171          * Initialize the driver key support routines to noop entries.
172          * This is useful especially for the cipher test modules.
173          */
174         vap->iv_key_alloc = null_key_alloc;
175         vap->iv_key_set = null_key_set;
176         vap->iv_key_delete = null_key_delete;
177         vap->iv_key_update_begin = null_key_update;
178         vap->iv_key_update_end = null_key_update;
179 }
180 
181 /*
182  * Teardown crypto support for a vap.
183  */
184 void
185 ieee80211_crypto_vdetach(struct ieee80211vap *vap)
186 {
187         ieee80211_crypto_delglobalkeys(vap);
188 }
189 
190 /*
191  * Register a crypto cipher module.
192  */
193 void
194 ieee80211_crypto_register(const struct ieee80211_cipher *cip)
195 {
196         if (cip->ic_cipher >= IEEE80211_CIPHER_MAX) {
197                 printf("%s: cipher %s has an invalid cipher index %u\n",
198                         __func__, cip->ic_name, cip->ic_cipher);
199                 return;
200         }
201         if (ciphers[cip->ic_cipher] != NULL && ciphers[cip->ic_cipher] != cip) {
202                 printf("%s: cipher %s registered with a different template\n",
203                         __func__, cip->ic_name);
204                 return;
205         }
206         ciphers[cip->ic_cipher] = cip;
207 }
208 
209 /*
210  * Unregister a crypto cipher module.
211  */
212 void
213 ieee80211_crypto_unregister(const struct ieee80211_cipher *cip)
214 {
215         if (cip->ic_cipher >= IEEE80211_CIPHER_MAX) {
216                 printf("%s: cipher %s has an invalid cipher index %u\n",
217                         __func__, cip->ic_name, cip->ic_cipher);
218                 return;
219         }
220         if (ciphers[cip->ic_cipher] != NULL && ciphers[cip->ic_cipher] != cip) {
221                 printf("%s: cipher %s registered with a different template\n",
222                         __func__, cip->ic_name);
223                 return;
224         }
225         /* NB: don't complain about not being registered */
226         /* XXX disallow if references */
227         ciphers[cip->ic_cipher] = NULL;
228 }
229 
230 int
231 ieee80211_crypto_available(u_int cipher)
232 {
233         return cipher < IEEE80211_CIPHER_MAX && ciphers[cipher] != NULL;
234 }
235 
236 /* XXX well-known names! */
237 static const char *cipher_modnames[IEEE80211_CIPHER_MAX] = {
238         "wlan_wep",     /* IEEE80211_CIPHER_WEP */
239         "wlan_tkip",    /* IEEE80211_CIPHER_TKIP */
240         "wlan_aes_ocb", /* IEEE80211_CIPHER_AES_OCB */
241         "wlan_ccmp",    /* IEEE80211_CIPHER_AES_CCM */
242         "#4",           /* reserved */
243         "wlan_ckip",    /* IEEE80211_CIPHER_CKIP */
244         "wlan_none",    /* IEEE80211_CIPHER_NONE */
245 };
246 
247 /*
248  * Establish a relationship between the specified key and cipher
249  * and, if necessary, allocate a hardware index from the driver.
250  * Note that when a fixed key index is required it must be specified
251  * and we blindly assign it w/o consulting the driver (XXX).
252  *
253  * This must be the first call applied to a key; all the other key
254  * routines assume wk_cipher is setup.
255  *
256  * Locking must be handled by the caller using:
257  *      ieee80211_key_update_begin(vap);
258  *      ieee80211_key_update_end(vap);
259  */
260 int
261 ieee80211_crypto_newkey(struct ieee80211vap *vap,
262         int cipher, int flags, struct ieee80211_key *key)
263 {
264         struct ieee80211com *ic = vap->iv_ic;
265         const struct ieee80211_cipher *cip;
266         ieee80211_keyix keyix, rxkeyix;
267         void *keyctx;
268         int oflags;
269 
270         IEEE80211_DPRINTF(vap, IEEE80211_MSG_CRYPTO,
271             "%s: cipher %u flags 0x%x keyix %u\n",
272             __func__, cipher, flags, key->wk_keyix);
273 
274         /*
275          * Validate cipher and set reference to cipher routines.
276          */
277         if (cipher >= IEEE80211_CIPHER_MAX) {
278                 IEEE80211_DPRINTF(vap, IEEE80211_MSG_CRYPTO,
279                     "%s: invalid cipher %u\n", __func__, cipher);
280                 vap->iv_stats.is_crypto_badcipher++;
281                 return 0;
282         }
283         cip = ciphers[cipher];
284         if (cip == NULL) {
285                 /*
286                  * Auto-load cipher module if we have a well-known name
287                  * for it.  It might be better to use string names rather
288                  * than numbers and craft a module name based on the cipher
289                  * name; e.g. wlan_cipher_<cipher-name>.
290                  */
291                 IEEE80211_DPRINTF(vap, IEEE80211_MSG_CRYPTO,
292                     "%s: unregistered cipher %u, load module %s\n",
293                     __func__, cipher, cipher_modnames[cipher]);
294                 ieee80211_load_module(cipher_modnames[cipher]);
295                 /*
296                  * If cipher module loaded it should immediately
297                  * call ieee80211_crypto_register which will fill
298                  * in the entry in the ciphers array.
299                  */
300                 cip = ciphers[cipher];
301                 if (cip == NULL) {
302                         IEEE80211_DPRINTF(vap, IEEE80211_MSG_CRYPTO,
303                             "%s: unable to load cipher %u, module %s\n",
304                             __func__, cipher, cipher_modnames[cipher]);
305                         vap->iv_stats.is_crypto_nocipher++;
306                         return 0;
307                 }
308         }
309 
310         oflags = key->wk_flags;
311         flags &= IEEE80211_KEY_COMMON;
312         /*
313          * If the hardware does not support the cipher then
314          * fallback to a host-based implementation.
315          */
316         if ((ic->ic_cryptocaps & (1<<cipher)) == 0) {
317                 IEEE80211_DPRINTF(vap, IEEE80211_MSG_CRYPTO,
318                     "%s: no h/w support for cipher %s, falling back to s/w\n",
319                     __func__, cip->ic_name);
320                 flags |= IEEE80211_KEY_SWCRYPT;
321         }
322         /*
323          * Hardware TKIP with software MIC is an important
324          * combination; we handle it by flagging each key,
325          * the cipher modules honor it.
326          */
327         if (cipher == IEEE80211_CIPHER_TKIP &&
328             (ic->ic_cryptocaps & IEEE80211_CRYPTO_TKIPMIC) == 0) {
329                 IEEE80211_DPRINTF(vap, IEEE80211_MSG_CRYPTO,
330                     "%s: no h/w support for TKIP MIC, falling back to s/w\n",
331                     __func__);
332                 flags |= IEEE80211_KEY_SWMIC;
333         }
334 
335         /*
336          * Bind cipher to key instance.  Note we do this
337          * after checking the device capabilities so the
338          * cipher module can optimize space usage based on
339          * whether or not it needs to do the cipher work.
340          */
341         if (key->wk_cipher != cip || key->wk_flags != flags) {
342                 /*
343                  * Fillin the flags so cipher modules can see s/w
344                  * crypto requirements and potentially allocate
345                  * different state and/or attach different method
346                  * pointers.
347                  */
348                 key->wk_flags = flags;
349                 keyctx = cip->ic_attach(vap, key);
350                 if (keyctx == NULL) {
351                         IEEE80211_DPRINTF(vap, IEEE80211_MSG_CRYPTO,
352                                 "%s: unable to attach cipher %s\n",
353                                 __func__, cip->ic_name);
354                         key->wk_flags = oflags; /* restore old flags */
355                         vap->iv_stats.is_crypto_attachfail++;
356                         return 0;
357                 }
358                 cipher_detach(key);
359                 key->wk_cipher = cip;           /* XXX refcnt? */
360                 key->wk_private = keyctx;
361         }
362         /*
363          * Commit to requested usage so driver can see the flags.
364          */
365         key->wk_flags = flags;
366 
367         /*
368          * Ask the driver for a key index if we don't have one.
369          * Note that entries in the global key table always have
370          * an index; this means it's safe to call this routine
371          * for these entries just to setup the reference to the
372          * cipher template.  Note also that when using software
373          * crypto we also call the driver to give us a key index.
374          */
375         if ((key->wk_flags & IEEE80211_KEY_DEVKEY) == 0) {
376                 if (!dev_key_alloc(vap, key, &keyix, &rxkeyix)) {
377                         /*
378                          * Unable to setup driver state.
379                          */
380                         vap->iv_stats.is_crypto_keyfail++;
381                         IEEE80211_DPRINTF(vap, IEEE80211_MSG_CRYPTO,
382                             "%s: unable to setup cipher %s\n",
383                             __func__, cip->ic_name);
384                         return 0;
385                 }
386                 if (key->wk_flags != flags) {
387                         /*
388                          * Driver overrode flags we setup; typically because
389                          * resources were unavailable to handle _this_ key.
390                          * Re-attach the cipher context to allow cipher
391                          * modules to handle differing requirements.
392                          */
393                         IEEE80211_DPRINTF(vap, IEEE80211_MSG_CRYPTO,
394                             "%s: driver override for cipher %s, flags "
395                             "0x%x -> 0x%x\n", __func__, cip->ic_name,
396                             oflags, key->wk_flags);
397                         keyctx = cip->ic_attach(vap, key);
398                         if (keyctx == NULL) {
399                                 IEEE80211_DPRINTF(vap, IEEE80211_MSG_CRYPTO,
400                                     "%s: unable to attach cipher %s with "
401                                     "flags 0x%x\n", __func__, cip->ic_name,
402                                     key->wk_flags);
403                                 key->wk_flags = oflags; /* restore old flags */
404                                 vap->iv_stats.is_crypto_attachfail++;
405                                 return 0;
406                         }
407                         cipher_detach(key);
408                         key->wk_cipher = cip;           /* XXX refcnt? */
409                         key->wk_private = keyctx;
410                 }
411                 key->wk_keyix = keyix;
412                 key->wk_rxkeyix = rxkeyix;
413                 key->wk_flags |= IEEE80211_KEY_DEVKEY;
414         }
415         return 1;
416 }
417 
418 /*
419  * Remove the key (no locking, for internal use).
420  */
421 static int
422 _ieee80211_crypto_delkey(struct ieee80211vap *vap, struct ieee80211_key *key)
423 {
424         KASSERT(key->wk_cipher != NULL, ("No cipher!"));
425 
426         IEEE80211_DPRINTF(vap, IEEE80211_MSG_CRYPTO,
427             "%s: %s keyix %u flags 0x%x rsc %ju tsc %ju len %u\n",
428             __func__, key->wk_cipher->ic_name,
429             key->wk_keyix, key->wk_flags,
430             key->wk_keyrsc[IEEE80211_NONQOS_TID], key->wk_keytsc,
431             key->wk_keylen);
432 
433         if (key->wk_flags & IEEE80211_KEY_DEVKEY) {
434                 /*
435                  * Remove hardware entry.
436                  */
437                 /* XXX key cache */
438                 if (!dev_key_delete(vap, key)) {
439                         IEEE80211_DPRINTF(vap, IEEE80211_MSG_CRYPTO,
440                             "%s: driver did not delete key index %u\n",
441                             __func__, key->wk_keyix);
442                         vap->iv_stats.is_crypto_delkey++;
443                         /* XXX recovery? */
444                 }
445         }
446         cipher_detach(key);
447         memset(key, 0, sizeof(*key));
448         ieee80211_crypto_resetkey(vap, key, IEEE80211_KEYIX_NONE);
449         return 1;
450 }
451 
452 /*
453  * Remove the specified key.
454  */
455 int
456 ieee80211_crypto_delkey(struct ieee80211vap *vap, struct ieee80211_key *key)
457 {
458         int status;
459 
460         ieee80211_key_update_begin(vap);
461         status = _ieee80211_crypto_delkey(vap, key);
462         ieee80211_key_update_end(vap);
463         return status;
464 }
465 
466 /*
467  * Clear the global key table.
468  */
469 void
470 ieee80211_crypto_delglobalkeys(struct ieee80211vap *vap)
471 {
472         int i;
473 
474         ieee80211_key_update_begin(vap);
475         for (i = 0; i < IEEE80211_WEP_NKID; i++)
476                 (void) _ieee80211_crypto_delkey(vap, &vap->iv_nw_keys[i]);
477         ieee80211_key_update_end(vap);
478 }
479 
480 /*
481  * Set the contents of the specified key.
482  *
483  * Locking must be handled by the caller using:
484  *      ieee80211_key_update_begin(vap);
485  *      ieee80211_key_update_end(vap);
486  */
487 int
488 ieee80211_crypto_setkey(struct ieee80211vap *vap, struct ieee80211_key *key)
489 {
490         const struct ieee80211_cipher *cip = key->wk_cipher;
491 
492         KASSERT(cip != NULL, ("No cipher!"));
493 
494         IEEE80211_DPRINTF(vap, IEEE80211_MSG_CRYPTO,
495             "%s: %s keyix %u flags 0x%x mac %s rsc %ju tsc %ju len %u\n",
496             __func__, cip->ic_name, key->wk_keyix,
497             key->wk_flags, ether_sprintf(key->wk_macaddr),
498             key->wk_keyrsc[IEEE80211_NONQOS_TID], key->wk_keytsc,
499             key->wk_keylen);
500 
501         if ((key->wk_flags & IEEE80211_KEY_DEVKEY)  == 0) {
502                 /* XXX nothing allocated, should not happen */
503                 IEEE80211_DPRINTF(vap, IEEE80211_MSG_CRYPTO,
504                     "%s: no device key setup done; should not happen!\n",
505                     __func__);
506                 vap->iv_stats.is_crypto_setkey_nokey++;
507                 return 0;
508         }
509         /*
510          * Give cipher a chance to validate key contents.
511          * XXX should happen before modifying state.
512          */
513         if (!cip->ic_setkey(key)) {
514                 IEEE80211_DPRINTF(vap, IEEE80211_MSG_CRYPTO,
515                     "%s: cipher %s rejected key index %u len %u flags 0x%x\n",
516                     __func__, cip->ic_name, key->wk_keyix,
517                     key->wk_keylen, key->wk_flags);
518                 vap->iv_stats.is_crypto_setkey_cipher++;
519                 return 0;
520         }
521         return dev_key_set(vap, key);
522 }
523 
524 /*
525  * Add privacy headers appropriate for the specified key.
526  */
527 struct ieee80211_key *
528 ieee80211_crypto_encap(struct ieee80211_node *ni, struct mbuf *m)
529 {
530         struct ieee80211vap *vap = ni->ni_vap;
531         struct ieee80211_key *k;
532         struct ieee80211_frame *wh;
533         const struct ieee80211_cipher *cip;
534         uint8_t keyid;
535 
536         /*
537          * Multicast traffic always uses the multicast key.
538          * Otherwise if a unicast key is set we use that and
539          * it is always key index 0.  When no unicast key is
540          * set we fall back to the default transmit key.
541          */
542         wh = mtod(m, struct ieee80211_frame *);
543         if (IEEE80211_IS_MULTICAST(wh->i_addr1) ||
544             IEEE80211_KEY_UNDEFINED(&ni->ni_ucastkey)) {
545                 if (vap->iv_def_txkey == IEEE80211_KEYIX_NONE) {
546                         IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_CRYPTO,
547                             wh->i_addr1,
548                             "no default transmit key (%s) deftxkey %u",
549                             __func__, vap->iv_def_txkey);
550                         vap->iv_stats.is_tx_nodefkey++;
551                         return NULL;
552                 }
553                 keyid = vap->iv_def_txkey;
554                 k = &vap->iv_nw_keys[vap->iv_def_txkey];
555         } else {
556                 keyid = 0;
557                 k = &ni->ni_ucastkey;
558         }
559         cip = k->wk_cipher;
560         return (cip->ic_encap(k, m, keyid<<6) ? k : NULL);
561 }
562 
563 /*
564  * Validate and strip privacy headers (and trailer) for a
565  * received frame that has the WEP/Privacy bit set.
566  */
567 struct ieee80211_key *
568 ieee80211_crypto_decap(struct ieee80211_node *ni, struct mbuf *m, int hdrlen)
569 {
570 #define IEEE80211_WEP_HDRLEN    (IEEE80211_WEP_IVLEN + IEEE80211_WEP_KIDLEN)
571 #define IEEE80211_WEP_MINLEN \
572         (sizeof(struct ieee80211_frame) + \
573         IEEE80211_WEP_HDRLEN + IEEE80211_WEP_CRCLEN)
574         struct ieee80211vap *vap = ni->ni_vap;
575         struct ieee80211_key *k;
576         struct ieee80211_frame *wh;
577         const struct ieee80211_cipher *cip;
578         uint8_t keyid;
579 
580         /* NB: this minimum size data frame could be bigger */
581         if (m->m_pkthdr.len < IEEE80211_WEP_MINLEN) {
582                 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ANY,
583                         "%s: WEP data frame too short, len %u\n",
584                         __func__, m->m_pkthdr.len);
585                 vap->iv_stats.is_rx_tooshort++; /* XXX need unique stat? */
586                 return NULL;
587         }
588 
589         /*
590          * Locate the key. If unicast and there is no unicast
591          * key then we fall back to the key id in the header.
592          * This assumes unicast keys are only configured when
593          * the key id in the header is meaningless (typically 0).
594          */
595         wh = mtod(m, struct ieee80211_frame *);
596         m_copydata(m, hdrlen + IEEE80211_WEP_IVLEN, sizeof(keyid), &keyid);
597         if (IEEE80211_IS_MULTICAST(wh->i_addr1) ||
598             IEEE80211_KEY_UNDEFINED(&ni->ni_ucastkey))
599                 k = &vap->iv_nw_keys[keyid >> 6];
600         else
601                 k = &ni->ni_ucastkey;
602 
603         /*
604          * Insure crypto header is contiguous for all decap work.
605          */
606         cip = k->wk_cipher;
607         if (m->m_len < hdrlen + cip->ic_header &&
608             (m = m_pullup(m, hdrlen + cip->ic_header)) == NULL) {
609                 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_CRYPTO, wh->i_addr2,
610                     "unable to pullup %s header", cip->ic_name);
611                 vap->iv_stats.is_rx_wepfail++;  /* XXX */
612                 return NULL;
613         }
614 
615         return (cip->ic_decap(k, m, hdrlen) ? k : NULL);
616 #undef IEEE80211_WEP_MINLEN
617 #undef IEEE80211_WEP_HDRLEN
618 }
619 
620 static void
621 load_ucastkey(void *arg, struct ieee80211_node *ni)
622 {
623         struct ieee80211vap *vap = ni->ni_vap;
624         struct ieee80211_key *k;
625 
626         if (vap->iv_state != IEEE80211_S_RUN)
627                 return;
628         k = &ni->ni_ucastkey;
629         if (k->wk_flags & IEEE80211_KEY_DEVKEY)
630                 dev_key_set(vap, k);
631 }
632 
633 /*
634  * Re-load all keys known to the 802.11 layer that may
635  * have hardware state backing them.  This is used by
636  * drivers on resume to push keys down into the device.
637  */
638 void
639 ieee80211_crypto_reload_keys(struct ieee80211com *ic)
640 {
641         struct ieee80211vap *vap;
642         int i;
643 
644         /*
645          * Keys in the global key table of each vap.
646          */
647         /* NB: used only during resume so don't lock for now */
648         TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
649                 if (vap->iv_state != IEEE80211_S_RUN)
650                         continue;
651                 for (i = 0; i < IEEE80211_WEP_NKID; i++) {
652                         const struct ieee80211_key *k = &vap->iv_nw_keys[i];
653                         if (k->wk_flags & IEEE80211_KEY_DEVKEY)
654                                 dev_key_set(vap, k);
655                 }
656         }
657         /*
658          * Unicast keys.
659          */
660         ieee80211_iterate_nodes(&ic->ic_sta, load_ucastkey, NULL);
661 }
662 

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