1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2007-2009 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 *
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: releng/12.0/sys/net80211/ieee80211_input.h 326272 2017-11-27 15:23:17Z pfg $
28 */
29#ifndef _NET80211_IEEE80211_INPUT_H_
30#define _NET80211_IEEE80211_INPUT_H_
31
32/* Verify the existence and length of __elem or get out. */
33#define IEEE80211_VERIFY_ELEMENT(__elem, __maxlen, _action) do {	\
34	if ((__elem) == NULL) {						\
35		IEEE80211_DISCARD(vap, IEEE80211_MSG_ELEMID,		\
36		    wh, NULL, "%s", "no " #__elem );			\
37		vap->iv_stats.is_rx_elem_missing++;			\
38		_action;						\
39	} else if ((__elem)[1] > (__maxlen)) {				\
40		IEEE80211_DISCARD(vap, IEEE80211_MSG_ELEMID,		\
41		    wh, NULL, "bad " #__elem " len %d", (__elem)[1]);	\
42		vap->iv_stats.is_rx_elem_toobig++;			\
43		_action;						\
44	}								\
45} while (0)
46
47#define	IEEE80211_VERIFY_LENGTH(_len, _minlen, _action) do {		\
48	if ((_len) < (_minlen)) {					\
49		IEEE80211_DISCARD(vap, IEEE80211_MSG_ELEMID,		\
50		    wh, NULL, "ie too short, got %d, expected %d",	\
51		    (_len), (_minlen));					\
52		vap->iv_stats.is_rx_elem_toosmall++;			\
53		_action;						\
54	}								\
55} while (0)
56
57#ifdef IEEE80211_DEBUG
58void	ieee80211_ssid_mismatch(struct ieee80211vap *, const char *tag,
59	uint8_t mac[IEEE80211_ADDR_LEN], uint8_t *ssid);
60
61#define	IEEE80211_VERIFY_SSID(_ni, _ssid, _action) do {			\
62	if ((_ssid)[1] != 0 &&						\
63	    ((_ssid)[1] != (_ni)->ni_esslen ||				\
64	    memcmp((_ssid) + 2, (_ni)->ni_essid, (_ssid)[1]) != 0)) {	\
65		if (ieee80211_msg_input(vap))				\
66			ieee80211_ssid_mismatch(vap, 			\
67			    ieee80211_mgt_subtype_name(subtype),	\
68				wh->i_addr2, _ssid);			\
69		vap->iv_stats.is_rx_ssidmismatch++;			\
70		_action;						\
71	}								\
72} while (0)
73#else /* !IEEE80211_DEBUG */
74#define	IEEE80211_VERIFY_SSID(_ni, _ssid, _action) do {			\
75	if ((_ssid)[1] != 0 &&						\
76	    ((_ssid)[1] != (_ni)->ni_esslen ||				\
77	    memcmp((_ssid) + 2, (_ni)->ni_essid, (_ssid)[1]) != 0)) {	\
78		vap->iv_stats.is_rx_ssidmismatch++;			\
79		_action;						\
80	}								\
81} while (0)
82#endif /* !IEEE80211_DEBUG */
83
84#include <sys/endian.h>		/* For le16toh() / le32dec() */
85
86static __inline int
87iswpaoui(const uint8_t *frm)
88{
89	return frm[1] > 3 && le32dec(frm+2) == ((WPA_OUI_TYPE<<24)|WPA_OUI);
90}
91
92static __inline int
93iswmeoui(const uint8_t *frm)
94{
95	return frm[1] > 3 && le32dec(frm+2) == ((WME_OUI_TYPE<<24)|WME_OUI);
96}
97
98static __inline int
99iswmeparam(const uint8_t *frm)
100{
101	return frm[1] > 5 && le32dec(frm+2) == ((WME_OUI_TYPE<<24)|WME_OUI) &&
102		frm[6] == WME_PARAM_OUI_SUBTYPE;
103}
104
105static __inline int
106iswmeinfo(const uint8_t *frm)
107{
108	return frm[1] > 5 && le32dec(frm+2) == ((WME_OUI_TYPE<<24)|WME_OUI) &&
109		frm[6] == WME_INFO_OUI_SUBTYPE;
110}
111
112static __inline int
113isatherosoui(const uint8_t *frm)
114{
115	return frm[1] > 3 && le32dec(frm+2) == ((ATH_OUI_TYPE<<24)|ATH_OUI);
116}
117
118static __inline int
119istdmaoui(const uint8_t *frm)
120{
121	return frm[1] > 3 && le32dec(frm+2) == ((TDMA_OUI_TYPE<<24)|TDMA_OUI);
122}
123
124static __inline int
125ishtcapoui(const uint8_t *frm)
126{
127	return frm[1] > 3 && le32dec(frm+2) == ((BCM_OUI_HTCAP<<24)|BCM_OUI);
128}
129
130static __inline int
131ishtinfooui(const uint8_t *frm)
132{
133	return frm[1] > 3 && le32dec(frm+2) == ((BCM_OUI_HTINFO<<24)|BCM_OUI);
134}
135
136static __inline int
137ieee80211_check_rxseq_amsdu(const struct ieee80211_rx_stats *rxs)
138{
139	if (rxs == NULL)
140		return 0;
141	return (!! (rxs->c_pktflags & IEEE80211_RX_F_AMSDU));
142}
143
144/*
145 * Return 1 if the rxseq check should increment the sequence
146 * number. Return 0 if it's part of an AMSDU batch and it isn't
147 * the final frame in the decap'ed burst.
148 */
149static __inline int
150ieee80211_check_rxseq_amsdu_more(const struct ieee80211_rx_stats *rxs)
151{
152	/* No state? ok */
153	if (rxs == NULL)
154		return (1);
155
156	/* State but no AMSDU set? ok */
157	if ((rxs->c_pktflags & IEEE80211_RX_F_AMSDU) == 0)
158		return (1);
159
160	/* State, AMSDU set, then _MORE means "don't inc yet" */
161	if (rxs->c_pktflags & IEEE80211_RX_F_AMSDU_MORE) {
162		return (0);
163	}
164
165	/* Both are set, so return ok */
166	return (1);
167}
168
169/*
170 * Check the current frame sequence number against the current TID
171 * state and return whether it's in sequence or should be dropped.
172 *
173 * Since out of order packet and duplicate packet eliminations should
174 * be done by the AMPDU RX code, this routine blindly accepts all
175 * frames from a HT station w/ a TID that is currently doing AMPDU-RX.
176 * HT stations without WME or where the TID is not doing AMPDU-RX
177 * are checked like non-HT stations.
178 *
179 * The routine only eliminates packets whose sequence/fragment
180 * match or are less than the last seen sequence/fragment number
181 * AND are retransmits It doesn't try to eliminate out of order packets.
182 *
183 * Since all frames after sequence number 4095 will be less than 4095
184 * (as the seqnum wraps), handle that special case so packets aren't
185 * incorrectly dropped - ie, if the next packet is sequence number 0
186 * but a retransmit since the initial packet didn't make it.
187 *
188 * XXX TODO: handle sequence number space wrapping with dropped frames;
189 * especially in high interference conditions under high traffic load
190 * The RX AMPDU reorder code also needs it.
191 *
192 * XXX TODO: update for 802.11-2012 9.3.2.10 Duplicate Detection and Recovery.
193 */
194static __inline int
195ieee80211_check_rxseq(struct ieee80211_node *ni, struct ieee80211_frame *wh,
196    uint8_t *bssid, const struct ieee80211_rx_stats *rxs)
197{
198#define	SEQ_LEQ(a,b)	((int)((a)-(b)) <= 0)
199#define	SEQ_EQ(a,b)	((int)((a)-(b)) == 0)
200#define	SEQNO(a)	((a) >> IEEE80211_SEQ_SEQ_SHIFT)
201#define	FRAGNO(a)	((a) & IEEE80211_SEQ_FRAG_MASK)
202	struct ieee80211vap *vap = ni->ni_vap;
203	uint16_t rxseq;
204	uint8_t type, subtype;
205	uint8_t tid;
206	struct ieee80211_rx_ampdu *rap;
207
208	rxseq = le16toh(*(uint16_t *)wh->i_seq);
209	type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
210	subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
211
212	/*
213	 * Types with no sequence number (or QoS (+)Null frames)
214	 * are always treated valid.
215	 */
216	if (! IEEE80211_HAS_SEQ(type, subtype))
217		return 1;
218
219	/*
220	 * Always allow multicast frames for now - QoS (any TID)
221	 * or not.
222	 */
223	if (IEEE80211_IS_MULTICAST(wh->i_addr1))
224		return 1;
225
226	tid = ieee80211_gettid(wh);
227
228	/*
229	 * Only do the HT AMPDU check for WME stations; non-WME HT stations
230	 * shouldn't exist outside of debugging. We should at least
231	 * handle that.
232	 */
233	if (tid < WME_NUM_TID) {
234		rap = &ni->ni_rx_ampdu[tid];
235		/* HT nodes currently doing RX AMPDU are always valid */
236		if ((ni->ni_flags & IEEE80211_NODE_HT) &&
237		    (rap->rxa_flags & IEEE80211_AGGR_RUNNING))
238			goto ok;
239	}
240
241	/*
242	 * Otherwise, retries for packets below or equal to the last
243	 * seen sequence number should be dropped.
244	 */
245
246	/*
247	 * Treat frame seqnum 4095 as special due to boundary
248	 * wrapping conditions.
249	 */
250	if (SEQNO(ni->ni_rxseqs[tid]) == 4095) {
251		/*
252		 * Drop retransmits on seqnum 4095/current fragment for itself.
253		 */
254		if (SEQ_EQ(rxseq, ni->ni_rxseqs[tid]) &&
255		    (wh->i_fc[1] & IEEE80211_FC1_RETRY))
256			goto fail;
257		/*
258		 * Treat any subsequent frame as fine if the last seen frame
259		 * is 4095 and it's not a retransmit for the same sequence
260		 * number. However, this doesn't capture incorrectly ordered
261	 	 * fragments w/ sequence number 4095. It shouldn't be seen
262		 * in practice, but see the comment above for further info.
263		 */
264		goto ok;
265	}
266
267	/*
268	 * At this point we assume that retransmitted seq/frag numbers below
269	 * the current can simply be eliminated.
270	 */
271	if ((wh->i_fc[1] & IEEE80211_FC1_RETRY) &&
272	    SEQ_LEQ(rxseq, ni->ni_rxseqs[tid]))
273		goto fail;
274
275ok:
276	/*
277	 * Only bump the sequence number if it's the last frame
278	 * in a batch.  That way frames in the rest of the batch
279	 * get included, and the last frame in the batch kicks
280	 * it next.
281	 */
282	if (ieee80211_check_rxseq_amsdu_more(rxs)) {
283		ni->ni_rxseqs[tid] = rxseq;
284		if ((rxs != NULL) && ieee80211_check_rxseq_amsdu(rxs))
285			IEEE80211_NODE_STAT(ni, rx_amsdu_more_end);
286	} else {
287		/* .. still waiting */
288		IEEE80211_NODE_STAT(ni, rx_amsdu_more);
289	}
290
291	return 1;
292
293fail:
294	/* duplicate, discard */
295	IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT, bssid, "duplicate",
296	    "seqno <%u,%u> fragno <%u,%u> tid %u",
297	     SEQNO(rxseq),  SEQNO(ni->ni_rxseqs[tid]),
298	    FRAGNO(rxseq), FRAGNO(ni->ni_rxseqs[tid]), tid);
299	vap->iv_stats.is_rx_dup++;
300	IEEE80211_NODE_STAT(ni, rx_dup);
301
302	return 0;
303#undef	SEQ_LEQ
304#undef	SEQ_EQ
305#undef	SEQNO
306#undef	FRAGNO
307}
308
309void	ieee80211_deliver_data(struct ieee80211vap *,
310		struct ieee80211_node *, struct mbuf *);
311struct mbuf *ieee80211_defrag(struct ieee80211_node *,
312		struct mbuf *, int);
313struct mbuf *ieee80211_realign(struct ieee80211vap *, struct mbuf *, size_t);
314struct mbuf *ieee80211_decap(struct ieee80211vap *, struct mbuf *, int);
315struct mbuf *ieee80211_decap1(struct mbuf *, int *);
316int	ieee80211_setup_rates(struct ieee80211_node *ni,
317		const uint8_t *rates, const uint8_t *xrates, int flags);
318void ieee80211_send_error(struct ieee80211_node *,
319		const uint8_t mac[IEEE80211_ADDR_LEN], int subtype, int arg);
320int	ieee80211_alloc_challenge(struct ieee80211_node *);
321int	ieee80211_parse_beacon(struct ieee80211_node *, struct mbuf *,
322		struct ieee80211_channel *,
323		struct ieee80211_scanparams *);
324int	ieee80211_parse_action(struct ieee80211_node *, struct mbuf *);
325#endif /* _NET80211_IEEE80211_INPUT_H_ */
326