ieee80211_input.h revision 282820
1/*-
2 * Copyright (c) 2007-2009 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 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 *
25 * $FreeBSD: head/sys/net80211/ieee80211_input.h 282820 2015-05-12 16:55:50Z adrian $
26 */
27#ifndef _NET80211_IEEE80211_INPUT_H_
28#define _NET80211_IEEE80211_INPUT_H_
29
30/* Verify the existence and length of __elem or get out. */
31#define IEEE80211_VERIFY_ELEMENT(__elem, __maxlen, _action) do {	\
32	if ((__elem) == NULL) {						\
33		IEEE80211_DISCARD(vap, IEEE80211_MSG_ELEMID,		\
34		    wh, NULL, "%s", "no " #__elem );			\
35		vap->iv_stats.is_rx_elem_missing++;			\
36		_action;						\
37	} else if ((__elem)[1] > (__maxlen)) {				\
38		IEEE80211_DISCARD(vap, IEEE80211_MSG_ELEMID,		\
39		    wh, NULL, "bad " #__elem " len %d", (__elem)[1]);	\
40		vap->iv_stats.is_rx_elem_toobig++;			\
41		_action;						\
42	}								\
43} while (0)
44
45#define	IEEE80211_VERIFY_LENGTH(_len, _minlen, _action) do {		\
46	if ((_len) < (_minlen)) {					\
47		IEEE80211_DISCARD(vap, IEEE80211_MSG_ELEMID,		\
48		    wh, NULL, "ie too short, got %d, expected %d",	\
49		    (_len), (_minlen));					\
50		vap->iv_stats.is_rx_elem_toosmall++;			\
51		_action;						\
52	}								\
53} while (0)
54
55#ifdef IEEE80211_DEBUG
56void	ieee80211_ssid_mismatch(struct ieee80211vap *, const char *tag,
57	uint8_t mac[IEEE80211_ADDR_LEN], uint8_t *ssid);
58
59#define	IEEE80211_VERIFY_SSID(_ni, _ssid, _action) do {			\
60	if ((_ssid)[1] != 0 &&						\
61	    ((_ssid)[1] != (_ni)->ni_esslen ||				\
62	    memcmp((_ssid) + 2, (_ni)->ni_essid, (_ssid)[1]) != 0)) {	\
63		if (ieee80211_msg_input(vap))				\
64			ieee80211_ssid_mismatch(vap, 			\
65			    ieee80211_mgt_subtype_name[subtype >>	\
66				IEEE80211_FC0_SUBTYPE_SHIFT],		\
67				wh->i_addr2, _ssid);			\
68		vap->iv_stats.is_rx_ssidmismatch++;			\
69		_action;						\
70	}								\
71} while (0)
72#else /* !IEEE80211_DEBUG */
73#define	IEEE80211_VERIFY_SSID(_ni, _ssid, _action) do {			\
74	if ((_ssid)[1] != 0 &&						\
75	    ((_ssid)[1] != (_ni)->ni_esslen ||				\
76	    memcmp((_ssid) + 2, (_ni)->ni_essid, (_ssid)[1]) != 0)) {	\
77		vap->iv_stats.is_rx_ssidmismatch++;			\
78		_action;						\
79	}								\
80} while (0)
81#endif /* !IEEE80211_DEBUG */
82
83/* unalligned little endian access */
84#define LE_READ_2(p)					\
85	((uint16_t)					\
86	 ((((const uint8_t *)(p))[0]      ) |		\
87	  (((const uint8_t *)(p))[1] <<  8)))
88#define LE_READ_4(p)					\
89	((uint32_t)					\
90	 ((((const uint8_t *)(p))[0]      ) |		\
91	  (((const uint8_t *)(p))[1] <<  8) |		\
92	  (((const uint8_t *)(p))[2] << 16) |		\
93	  (((const uint8_t *)(p))[3] << 24)))
94
95static __inline int
96iswpaoui(const uint8_t *frm)
97{
98	return frm[1] > 3 && LE_READ_4(frm+2) == ((WPA_OUI_TYPE<<24)|WPA_OUI);
99}
100
101static __inline int
102iswmeoui(const uint8_t *frm)
103{
104	return frm[1] > 3 && LE_READ_4(frm+2) == ((WME_OUI_TYPE<<24)|WME_OUI);
105}
106
107static __inline int
108iswmeparam(const uint8_t *frm)
109{
110	return frm[1] > 5 && LE_READ_4(frm+2) == ((WME_OUI_TYPE<<24)|WME_OUI) &&
111		frm[6] == WME_PARAM_OUI_SUBTYPE;
112}
113
114static __inline int
115iswmeinfo(const uint8_t *frm)
116{
117	return frm[1] > 5 && LE_READ_4(frm+2) == ((WME_OUI_TYPE<<24)|WME_OUI) &&
118		frm[6] == WME_INFO_OUI_SUBTYPE;
119}
120
121static __inline int
122isatherosoui(const uint8_t *frm)
123{
124	return frm[1] > 3 && LE_READ_4(frm+2) == ((ATH_OUI_TYPE<<24)|ATH_OUI);
125}
126
127static __inline int
128istdmaoui(const uint8_t *frm)
129{
130	return frm[1] > 3 && LE_READ_4(frm+2) == ((TDMA_OUI_TYPE<<24)|TDMA_OUI);
131}
132
133static __inline int
134ishtcapoui(const uint8_t *frm)
135{
136	return frm[1] > 3 && LE_READ_4(frm+2) == ((BCM_OUI_HTCAP<<24)|BCM_OUI);
137}
138
139static __inline int
140ishtinfooui(const uint8_t *frm)
141{
142	return frm[1] > 3 && LE_READ_4(frm+2) == ((BCM_OUI_HTINFO<<24)|BCM_OUI);
143}
144
145#include <sys/endian.h>		/* For le16toh() */
146
147/*
148 * Check the current frame sequence number against the current TID
149 * state and return whether it's in sequence or should be dropped.
150 *
151 * Since out of order packet and duplicate packet eliminations should
152 * be done by the AMPDU RX code, this routine blindly accepts all
153 * frames from a HT station w/ a TID that is currently doing AMPDU-RX.
154 * HT stations without WME or where the TID is not doing AMPDU-RX
155 * are checked like non-HT stations.
156 *
157 * The routine only eliminates packets whose sequence/fragment
158 * match or are less than the last seen sequence/fragment number
159 * AND are retransmits It doesn't try to eliminate out of order packets.
160 *
161 * Since all frames after sequence number 4095 will be less than 4095
162 * (as the seqnum wraps), handle that special case so packets aren't
163 * incorrectly dropped - ie, if the next packet is sequence number 0
164 * but a retransmit since the initial packet didn't make it.
165 */
166static __inline int
167ieee80211_check_rxseq(struct ieee80211_node *ni, struct ieee80211_frame *wh)
168{
169#define	SEQ_LEQ(a,b)	((int)((a)-(b)) <= 0)
170#define	SEQ_EQ(a,b)	((int)((a)-(b)) == 0)
171#define	SEQNO(a)	((a) >> IEEE80211_SEQ_SEQ_SHIFT)
172#define	FRAGNO(a)	((a) & IEEE80211_SEQ_FRAG_MASK)
173	uint16_t rxseq;
174	uint8_t type, subtype;
175	uint8_t tid;
176	struct ieee80211_rx_ampdu *rap;
177
178	rxseq = le16toh(*(uint16_t *)wh->i_seq);
179	type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
180	subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
181
182	/*
183	 * Types with no sequence number (or QoS (+)Null frames)
184	 * are always treated valid.
185	 */
186	if (! IEEE80211_HAS_SEQ(type, subtype))
187		return 1;
188
189	tid = ieee80211_gettid(wh);
190
191	/*
192	 * Only do the HT AMPDU check for WME stations; non-WME HT stations
193	 * shouldn't exist outside of debugging. We should at least
194	 * handle that.
195	 */
196	if (tid < WME_NUM_TID) {
197		rap = &ni->ni_rx_ampdu[tid];
198		/* HT nodes currently doing RX AMPDU are always valid */
199		if ((ni->ni_flags & IEEE80211_NODE_HT) &&
200		    (rap->rxa_flags & IEEE80211_AGGR_RUNNING))
201			return 1;
202	}
203
204	/*
205	 * Otherwise, retries for packets below or equal to the last
206	 * seen sequence number should be dropped.
207	 */
208
209	/*
210	 * Treat frame seqnum 4095 as special due to boundary
211	 * wrapping conditions.
212	 */
213	if (SEQNO(ni->ni_rxseqs[tid]) == 4095) {
214		/*
215		 * Drop retransmits on seqnum 4095/current fragment for itself.
216		 */
217		if (SEQ_EQ(rxseq, ni->ni_rxseqs[tid]) &&
218		    (wh->i_fc[1] & IEEE80211_FC1_RETRY))
219			return 0;
220		/*
221		 * Treat any subsequent frame as fine if the last seen frame
222		 * is 4095 and it's not a retransmit for the same sequence
223		 * number. However, this doesn't capture incorrectly ordered
224	 	 * fragments w/ sequence number 4095. It shouldn't be seen
225		 * in practice, but see the comment above for further info.
226		 */
227		return 1;
228	}
229
230	/*
231	 * At this point we assume that retransmitted seq/frag numbers below
232	 * the current can simply be eliminated.
233	 */
234	if ((wh->i_fc[1] & IEEE80211_FC1_RETRY) &&
235	    SEQ_LEQ(rxseq, ni->ni_rxseqs[tid]))
236		return 0;
237
238	return 1;
239#undef	SEQ_LEQ
240#undef	SEQ_EQ
241#undef	SEQNO
242#undef	FRAGNO
243}
244
245void	ieee80211_deliver_data(struct ieee80211vap *,
246		struct ieee80211_node *, struct mbuf *);
247struct mbuf *ieee80211_defrag(struct ieee80211_node *,
248		struct mbuf *, int);
249struct mbuf *ieee80211_realign(struct ieee80211vap *, struct mbuf *, size_t);
250struct mbuf *ieee80211_decap(struct ieee80211vap *, struct mbuf *, int);
251struct mbuf *ieee80211_decap1(struct mbuf *, int *);
252int	ieee80211_setup_rates(struct ieee80211_node *ni,
253		const uint8_t *rates, const uint8_t *xrates, int flags);
254void ieee80211_send_error(struct ieee80211_node *,
255		const uint8_t mac[IEEE80211_ADDR_LEN], int subtype, int arg);
256int	ieee80211_alloc_challenge(struct ieee80211_node *);
257int	ieee80211_parse_beacon(struct ieee80211_node *, struct mbuf *,
258		struct ieee80211_scanparams *);
259int	ieee80211_parse_action(struct ieee80211_node *, struct mbuf *);
260#endif /* _NET80211_IEEE80211_INPUT_H_ */
261