1 /*
2  * Copyright (c) 2003-2005 Sam Leffler, Errno Consulting
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  *
27  * $FreeBSD: src/sys/net80211/ieee80211_freebsd.c,v 1.7.2.2 2005/12/22 19:22:51 sam Exp $
28  * $DragonFly: src/sys/netproto/802_11/wlan/ieee80211_dragonfly.c,v 1.1 2006/05/18 13:51:46 sephe Exp $
29  */
30 
31 /*
32  * IEEE 802.11 support (DragonFlyBSD-specific code)
33  */
34 #include <sys/param.h>
35 #include <sys/kernel.h>
36 #include <sys/systm.h>
37 #include <sys/linker.h>
38 #include <sys/mbuf.h>
39 #include <sys/module.h>
40 #include <sys/proc.h>
41 #include <sys/sysctl.h>
42 
43 #include <sys/socket.h>
44 
45 #include <net/if.h>
46 #include <net/if_arp.h>
47 #include <net/if_media.h>
48 #include <net/ethernet.h>
49 #include <net/route.h>
50 
51 #include <netproto/802_11/ieee80211_var.h>
52 
53 #define if_link_state_change(ifp, state)	((void)0)
54 
55 SYSCTL_NODE(_net, OID_AUTO, wlan, CTLFLAG_RD, 0, "IEEE 80211 parameters");
56 
57 #ifdef IEEE80211_DEBUG
58 int	ieee80211_debug = 0;
59 SYSCTL_INT(_net_wlan, OID_AUTO, debug, CTLFLAG_RW, &ieee80211_debug,
60 	    0, "debugging printfs");
61 #endif
62 
63 static int
64 ieee80211_sysctl_inact(SYSCTL_HANDLER_ARGS)
65 {
66 	int inact = (*(int *)arg1) * IEEE80211_INACT_WAIT;
67 	int error;
68 
69 	error = sysctl_handle_int(oidp, &inact, 0, req);
70 	if (error || !req->newptr)
71 		return error;
72 	*(int *)arg1 = inact / IEEE80211_INACT_WAIT;
73 	return 0;
74 }
75 
76 static int
77 ieee80211_sysctl_parent(SYSCTL_HANDLER_ARGS)
78 {
79 	struct ieee80211com *ic = arg1;
80 	const char *name = ic->ic_ifp->if_xname;
81 
82 	return SYSCTL_OUT(req, name, strlen(name));
83 }
84 
85 void
86 ieee80211_sysctl_attach(struct ieee80211com *ic)
87 {
88 	struct sysctl_ctx_list *ctx;
89 	struct sysctl_oid *oid;
90 	char num[14];			/* sufficient for 32 bits */
91 
92 	ctx = malloc(sizeof(struct sysctl_ctx_list), M_DEVBUF,
93 		     M_WAITOK | M_ZERO);
94 	sysctl_ctx_init(ctx);
95 
96 	snprintf(num, sizeof(num), "%u", ic->ic_vap);
97 	oid = SYSCTL_ADD_NODE(ctx, &SYSCTL_NODE_CHILDREN(_net, wlan),
98 		OID_AUTO, num, CTLFLAG_RD, NULL, "");
99 	if (oid == NULL)
100 		return;
101 
102 	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(oid), OID_AUTO,
103 		"%parent", CTLFLAG_RD, ic, 0, ieee80211_sysctl_parent, "A",
104 		"parent device");
105 #ifdef IEEE80211_DEBUG
106 	ic->ic_debug = ieee80211_debug;
107 	SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(oid), OID_AUTO,
108 		"debug", CTLFLAG_RW, &ic->ic_debug, 0,
109 		"control debugging printfs");
110 #endif
111 	/* XXX inherit from tunables */
112 	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(oid), OID_AUTO,
113 		"inact_run", CTLTYPE_INT | CTLFLAG_RW, &ic->ic_inact_run, 0,
114 		ieee80211_sysctl_inact, "I",
115 		"station inactivity timeout (sec)");
116 	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(oid), OID_AUTO,
117 		"inact_probe", CTLTYPE_INT | CTLFLAG_RW, &ic->ic_inact_probe, 0,
118 		ieee80211_sysctl_inact, "I",
119 		"station inactivity probe timeout (sec)");
120 	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(oid), OID_AUTO,
121 		"inact_auth", CTLTYPE_INT | CTLFLAG_RW, &ic->ic_inact_auth, 0,
122 		ieee80211_sysctl_inact, "I",
123 		"station authentication timeout (sec)");
124 	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(oid), OID_AUTO,
125 		"inact_init", CTLTYPE_INT | CTLFLAG_RW, &ic->ic_inact_init, 0,
126 		ieee80211_sysctl_inact, "I",
127 		"station initial state timeout (sec)");
128 	SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(oid), OID_AUTO,
129 		"driver_caps", CTLFLAG_RW, &ic->ic_caps, 0,
130 		"driver capabilities");
131 	SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(oid), OID_AUTO,
132 		"bmiss_max", CTLFLAG_RW, &ic->ic_bmiss_max, 0,
133 		"consecutive beacon misses before scanning");
134 
135 	ic->ic_sysctl = ctx;
136 }
137 
138 void
139 ieee80211_sysctl_detach(struct ieee80211com *ic)
140 {
141 	if (ic->ic_sysctl != NULL) {
142 		sysctl_ctx_free(ic->ic_sysctl);
143 		free(ic->ic_sysctl, M_DEVBUF);
144 		ic->ic_sysctl = NULL;
145 	}
146 }
147 
148 int
149 ieee80211_node_dectestref(struct ieee80211_node *ni)
150 {
151 	/* XXX need equivalent of atomic_dec_and_test */
152 	atomic_subtract_int(&ni->ni_refcnt, 1);
153 	return atomic_cmpset_int(&ni->ni_refcnt, 0, 1);
154 }
155 
156 /*
157  * Allocate and setup a management frame of the specified
158  * size.  We return the mbuf and a pointer to the start
159  * of the contiguous data area that's been reserved based
160  * on the packet length.  The data area is forced to 32-bit
161  * alignment and the buffer length to a multiple of 4 bytes.
162  * This is done mainly so beacon frames (that require this)
163  * can use this interface too.
164  */
165 struct mbuf *
166 ieee80211_getmgtframe(uint8_t **frm, u_int pktlen)
167 {
168 	struct mbuf *m;
169 	u_int len;
170 
171 	/*
172 	 * NB: we know the mbuf routines will align the data area
173 	 *     so we don't need to do anything special.
174 	 */
175 	/* XXX 4-address frame? */
176 	len = roundup(sizeof(struct ieee80211_frame) + pktlen, 4);
177 	KASSERT(len <= MCLBYTES, ("802.11 mgt frame too large: %u", len));
178 	if (len < MINCLSIZE) {
179 		m = m_gethdr(M_NOWAIT, MT_HEADER);
180 		/*
181 		 * Align the data in case additional headers are added.
182 		 * This should only happen when a WEP header is added
183 		 * which only happens for shared key authentication mgt
184 		 * frames which all fit in MHLEN.
185 		 */
186 		if (m != NULL)
187 			MH_ALIGN(m, len);
188 	} else
189 		m = m_getcl(M_NOWAIT, MT_HEADER, M_PKTHDR);
190 	if (m != NULL) {
191 		m->m_data += sizeof(struct ieee80211_frame);
192 		*frm = m->m_data;
193 	}
194 	return m;
195 }
196 
197 #include <sys/libkern.h>
198 
199 void
200 get_random_bytes(void *p, size_t n)
201 {
202 	uint8_t *dp = p;
203 
204 	while (n > 0) {
205 		uint32_t v = arc4random();
206 		size_t nb = n > sizeof(uint32_t) ? sizeof(uint32_t) : n;
207 
208 		bcopy(&v, dp, n > sizeof(uint32_t) ? sizeof(uint32_t) : n);
209 		dp += sizeof(uint32_t), n -= nb;
210 	}
211 }
212 
213 void
214 ieee80211_notify_node_join(struct ieee80211com *ic, struct ieee80211_node *ni,
215 			   int newassoc)
216 {
217 	struct ifnet *ifp = ic->ic_ifp;
218 	struct ieee80211_join_event iev;
219 
220 	memset(&iev, 0, sizeof(iev));
221 	if (ni == ic->ic_bss) {
222 		IEEE80211_ADDR_COPY(iev.iev_addr, ni->ni_bssid);
223 		rt_ieee80211msg(ifp, newassoc ?
224 			RTM_IEEE80211_ASSOC : RTM_IEEE80211_REASSOC,
225 			&iev, sizeof(iev));
226 		if_link_state_change(ifp, LINK_STATE_UP);
227 	} else {
228 		IEEE80211_ADDR_COPY(iev.iev_addr, ni->ni_macaddr);
229 		rt_ieee80211msg(ifp, newassoc ?
230 			RTM_IEEE80211_JOIN : RTM_IEEE80211_REJOIN,
231 			&iev, sizeof(iev));
232 	}
233 }
234 
235 void
236 ieee80211_notify_node_leave(struct ieee80211com *ic, struct ieee80211_node *ni)
237 {
238 	struct ifnet *ifp = ic->ic_ifp;
239 	struct ieee80211_leave_event iev;
240 
241 	if (ni == ic->ic_bss) {
242 		rt_ieee80211msg(ifp, RTM_IEEE80211_DISASSOC, NULL, 0);
243 		if_link_state_change(ifp, LINK_STATE_DOWN);
244 	} else {
245 		/* fire off wireless event station leaving */
246 		memset(&iev, 0, sizeof(iev));
247 		IEEE80211_ADDR_COPY(iev.iev_addr, ni->ni_macaddr);
248 		rt_ieee80211msg(ifp, RTM_IEEE80211_LEAVE, &iev, sizeof(iev));
249 	}
250 }
251 
252 void
253 ieee80211_notify_scan_done(struct ieee80211com *ic)
254 {
255 	struct ifnet *ifp = ic->ic_ifp;
256 
257 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
258 		"%s: notify scan done\n", ic->ic_ifp->if_xname);
259 
260 	/* dispatch wireless event indicating scan completed */
261 	rt_ieee80211msg(ifp, RTM_IEEE80211_SCAN, NULL, 0);
262 }
263 
264 void
265 ieee80211_notify_replay_failure(struct ieee80211com *ic,
266 	const struct ieee80211_frame *wh, const struct ieee80211_key *k,
267 	uint64_t rsc)
268 {
269 	struct ifnet *ifp = ic->ic_ifp;
270 
271 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_CRYPTO,
272 	    "[%6D] %s replay detected <rsc %ju, csc %ju, keyix %u rxkeyix %u>\n",
273 	    wh->i_addr2, ":", k->wk_cipher->ic_name,
274 	    (intmax_t) rsc, (intmax_t) k->wk_keyrsc,
275 	    k->wk_keyix, k->wk_rxkeyix);
276 
277 	if (ifp != NULL) {		/* NB: for cipher test modules */
278 		struct ieee80211_replay_event iev;
279 
280 		IEEE80211_ADDR_COPY(iev.iev_dst, wh->i_addr1);
281 		IEEE80211_ADDR_COPY(iev.iev_src, wh->i_addr2);
282 		iev.iev_cipher = k->wk_cipher->ic_cipher;
283 		if (k->wk_rxkeyix != IEEE80211_KEYIX_NONE)
284 			iev.iev_keyix = k->wk_rxkeyix;
285 		else
286 			iev.iev_keyix = k->wk_keyix;
287 		iev.iev_keyrsc = k->wk_keyrsc;
288 		iev.iev_rsc = rsc;
289 		rt_ieee80211msg(ifp, RTM_IEEE80211_REPLAY, &iev, sizeof(iev));
290 	}
291 }
292 
293 void
294 ieee80211_notify_michael_failure(struct ieee80211com *ic,
295 	const struct ieee80211_frame *wh, u_int keyix)
296 {
297 	struct ifnet *ifp = ic->ic_ifp;
298 
299 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_CRYPTO,
300 		"[%6D] michael MIC verification failed <keyix %u>\n",
301 	       wh->i_addr2, ":", keyix);
302 	ic->ic_stats.is_rx_tkipmic++;
303 
304 	if (ifp != NULL) {		/* NB: for cipher test modules */
305 		struct ieee80211_michael_event iev;
306 
307 		IEEE80211_ADDR_COPY(iev.iev_dst, wh->i_addr1);
308 		IEEE80211_ADDR_COPY(iev.iev_src, wh->i_addr2);
309 		iev.iev_cipher = IEEE80211_CIPHER_TKIP;
310 		iev.iev_keyix = keyix;
311 		rt_ieee80211msg(ifp, RTM_IEEE80211_MICHAEL, &iev, sizeof(iev));
312 	}
313 }
314 
315 void
316 ieee80211_load_module(const char *modname)
317 {
318 #ifdef notyet
319 	struct thread *td = curthread;
320 
321 	if (suser(td) == 0 && securelevel_gt(td->td_ucred, 0) == 0) {
322 		crit_enter();	/* NB: need BGL here */
323 		linker_load_module(modname, NULL, NULL, NULL, NULL);
324 		crit_exit();
325 	}
326 #else
327 	printf("%s: load the %s module by hand for now.\n", __func__, modname);
328 #endif
329 }
330 
331 /*
332  * Append the specified data to the indicated mbuf chain,
333  * Extend the mbuf chain if the new data does not fit in
334  * existing space.
335  *
336  * Return 1 if able to complete the job; otherwise 0.
337  */
338 int
339 ieee80211_mbuf_append(struct mbuf *m0, int len, const uint8_t *cp)
340 {
341 	struct mbuf *m, *n;
342 	int remainder, space;
343 
344 	for (m = m0; m->m_next != NULL; m = m->m_next)
345 		;
346 	remainder = len;
347 	space = M_TRAILINGSPACE(m);
348 	if (space > 0) {
349 		/*
350 		 * Copy into available space.
351 		 */
352 		if (space > remainder)
353 			space = remainder;
354 		bcopy(cp, mtod(m, caddr_t) + m->m_len, space);
355 		m->m_len += space;
356 		cp += space, remainder -= space;
357 	}
358 	while (remainder > 0) {
359 		/*
360 		 * Allocate a new mbuf; could check space
361 		 * and allocate a cluster instead.
362 		 */
363 		n = m_get(MB_DONTWAIT, m->m_type);
364 		if (n == NULL)
365 			break;
366 		n->m_len = min(MLEN, remainder);
367 		bcopy(cp, mtod(n, caddr_t), n->m_len);
368 		cp += n->m_len, remainder -= n->m_len;
369 		m->m_next = n;
370 		m = n;
371 	}
372 	if (m0->m_flags & M_PKTHDR)
373 		m0->m_pkthdr.len += len - remainder;
374 	return (remainder == 0);
375 }
376 
377 /*
378  * Create a writable copy of the mbuf chain.  While doing this
379  * we compact the chain with a goal of producing a chain with
380  * at most two mbufs.  The second mbuf in this chain is likely
381  * to be a cluster.  The primary purpose of this work is to create
382  * a writable packet for encryption, compression, etc.  The
383  * secondary goal is to linearize the data so the data can be
384  * passed to crypto hardware in the most efficient manner possible.
385  */
386 struct mbuf *
387 ieee80211_mbuf_clone(struct mbuf *m0, int how)
388 {
389 	struct mbuf *m, *mprev;
390 	struct mbuf *n, *mfirst, *mlast;
391 	int len, off;
392 
393 	mprev = NULL;
394 	for (m = m0; m != NULL; m = mprev->m_next) {
395 		/*
396 		 * Regular mbufs are ignored unless there's a cluster
397 		 * in front of it that we can use to coalesce.  We do
398 		 * the latter mainly so later clusters can be coalesced
399 		 * also w/o having to handle them specially (i.e. convert
400 		 * mbuf+cluster -> cluster).  This optimization is heavily
401 		 * influenced by the assumption that we're running over
402 		 * Ethernet where MCLBYTES is large enough that the max
403 		 * packet size will permit lots of coalescing into a
404 		 * single cluster.  This in turn permits efficient
405 		 * crypto operations, especially when using hardware.
406 		 */
407 		if ((m->m_flags & M_EXT) == 0) {
408 			if (mprev && (mprev->m_flags & M_EXT) &&
409 			    m->m_len <= M_TRAILINGSPACE(mprev)) {
410 				/* XXX: this ignores mbuf types */
411 				memcpy(mtod(mprev, caddr_t) + mprev->m_len,
412 				       mtod(m, caddr_t), m->m_len);
413 				mprev->m_len += m->m_len;
414 				mprev->m_next = m->m_next;	/* unlink from chain */
415 				m_free(m);			/* reclaim mbuf */
416 			} else {
417 				mprev = m;
418 			}
419 			continue;
420 		}
421 		/*
422 		 * Writable mbufs are left alone (for now).
423 		 */
424 		if (M_WRITABLE(m)) {
425 			mprev = m;
426 			continue;
427 		}
428 
429 		/*
430 		 * Not writable, replace with a copy or coalesce with
431 		 * the previous mbuf if possible (since we have to copy
432 		 * it anyway, we try to reduce the number of mbufs and
433 		 * clusters so that future work is easier).
434 		 */
435 		KASSERT(m->m_flags & M_EXT, ("m_flags 0x%x", m->m_flags));
436 		/* NB: we only coalesce into a cluster or larger */
437 		if (mprev != NULL && (mprev->m_flags & M_EXT) &&
438 		    m->m_len <= M_TRAILINGSPACE(mprev)) {
439 			/* XXX: this ignores mbuf types */
440 			memcpy(mtod(mprev, caddr_t) + mprev->m_len,
441 			       mtod(m, caddr_t), m->m_len);
442 			mprev->m_len += m->m_len;
443 			mprev->m_next = m->m_next;	/* unlink from chain */
444 			m_free(m);			/* reclaim mbuf */
445 			continue;
446 		}
447 
448 		/*
449 		 * Allocate new space to hold the copy...
450 		 */
451 		/* XXX why can M_PKTHDR be set past the first mbuf? */
452 		if (mprev == NULL && (m->m_flags & M_PKTHDR)) {
453 			/*
454 			 * NB: if a packet header is present we must
455 			 * allocate the mbuf separately from any cluster
456 			 * because M_MOVE_PKTHDR will smash the data
457 			 * pointer and drop the M_EXT marker.
458 			 */
459 			MGETHDR(n, how, m->m_type);
460 			if (n == NULL) {
461 				m_freem(m0);
462 				return (NULL);
463 			}
464 			M_MOVE_PKTHDR(n, m);
465 			MCLGET(n, how);
466 			if ((n->m_flags & M_EXT) == 0) {
467 				m_free(n);
468 				m_freem(m0);
469 				return (NULL);
470 			}
471 		} else {
472 			n = m_getcl(how, m->m_type, m->m_flags);
473 			if (n == NULL) {
474 				m_freem(m0);
475 				return (NULL);
476 			}
477 		}
478 		/*
479 		 * ... and copy the data.  We deal with jumbo mbufs
480 		 * (i.e. m_len > MCLBYTES) by splitting them into
481 		 * clusters.  We could just malloc a buffer and make
482 		 * it external but too many device drivers don't know
483 		 * how to break up the non-contiguous memory when
484 		 * doing DMA.
485 		 */
486 		len = m->m_len;
487 		off = 0;
488 		mfirst = n;
489 		mlast = NULL;
490 		for (;;) {
491 			int cc = min(len, MCLBYTES);
492 			memcpy(mtod(n, caddr_t), mtod(m, caddr_t) + off, cc);
493 			n->m_len = cc;
494 			if (mlast != NULL)
495 				mlast->m_next = n;
496 			mlast = n;
497 
498 			len -= cc;
499 			if (len <= 0)
500 				break;
501 			off += cc;
502 
503 			n = m_getcl(how, m->m_type, m->m_flags);
504 			if (n == NULL) {
505 				m_freem(mfirst);
506 				m_freem(m0);
507 				return (NULL);
508 			}
509 		}
510 		n->m_next = m->m_next;
511 		if (mprev == NULL)
512 			m0 = mfirst;		/* new head of chain */
513 		else
514 			mprev->m_next = mfirst;	/* replace old mbuf */
515 		m_free(m);			/* release old mbuf */
516 		mprev = mfirst;
517 	}
518 	return (m0);
519 }
520 
521 /*
522  * Module glue.
523  *
524  * NB: the module name is "wlan" for compatibility with NetBSD.
525  */
526 static int
527 wlan_modevent(module_t mod, int type, void *unused)
528 {
529 	switch (type) {
530 	case MOD_LOAD:
531 		if (bootverbose)
532 			printf("wlan: <802.11 Link Layer>\n");
533 		return 0;
534 	case MOD_UNLOAD:
535 		return 0;
536 	}
537 	return EINVAL;
538 }
539 
540 static moduledata_t wlan_mod = {
541 	"wlan",
542 	wlan_modevent,
543 	0
544 };
545 DECLARE_MODULE(wlan, wlan_mod, SI_SUB_DRIVERS, SI_ORDER_FIRST);
546 MODULE_VERSION(wlan, 1);
547 MODULE_DEPEND(wlan, crypto, 1, 1, 1);
548