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: stable/11/sys/net80211/ieee80211_input.h 330241 2018-03-01 15:21:52Z eadler $
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				wh->i_addr2, _ssid);			\
67		vap->iv_stats.is_rx_ssidmismatch++;			\
68		_action;						\
69	}								\
70} while (0)
71#else /* !IEEE80211_DEBUG */
72#define	IEEE80211_VERIFY_SSID(_ni, _ssid, _action) do {			\
73	if ((_ssid)[1] != 0 &&						\
74	    ((_ssid)[1] != (_ni)->ni_esslen ||				\
75	    memcmp((_ssid) + 2, (_ni)->ni_essid, (_ssid)[1]) != 0)) {	\
76		vap->iv_stats.is_rx_ssidmismatch++;			\
77		_action;						\
78	}								\
79} while (0)
80#endif /* !IEEE80211_DEBUG */
81
82#include <sys/endian.h>		/* For le16toh() / le32dec() */
83
84static __inline int
85iswpaoui(const uint8_t *frm)
86{
87	return frm[1] > 3 && le32dec(frm+2) == ((WPA_OUI_TYPE<<24)|WPA_OUI);
88}
89
90static __inline int
91iswmeoui(const uint8_t *frm)
92{
93	return frm[1] > 3 && le32dec(frm+2) == ((WME_OUI_TYPE<<24)|WME_OUI);
94}
95
96static __inline int
97iswmeparam(const uint8_t *frm)
98{
99	return frm[1] > 5 && le32dec(frm+2) == ((WME_OUI_TYPE<<24)|WME_OUI) &&
100		frm[6] == WME_PARAM_OUI_SUBTYPE;
101}
102
103static __inline int
104iswmeinfo(const uint8_t *frm)
105{
106	return frm[1] > 5 && le32dec(frm+2) == ((WME_OUI_TYPE<<24)|WME_OUI) &&
107		frm[6] == WME_INFO_OUI_SUBTYPE;
108}
109
110static __inline int
111isatherosoui(const uint8_t *frm)
112{
113	return frm[1] > 3 && le32dec(frm+2) == ((ATH_OUI_TYPE<<24)|ATH_OUI);
114}
115
116static __inline int
117istdmaoui(const uint8_t *frm)
118{
119	return frm[1] > 3 && le32dec(frm+2) == ((TDMA_OUI_TYPE<<24)|TDMA_OUI);
120}
121
122static __inline int
123ishtcapoui(const uint8_t *frm)
124{
125	return frm[1] > 3 && le32dec(frm+2) == ((BCM_OUI_HTCAP<<24)|BCM_OUI);
126}
127
128static __inline int
129ishtinfooui(const uint8_t *frm)
130{
131	return frm[1] > 3 && le32dec(frm+2) == ((BCM_OUI_HTINFO<<24)|BCM_OUI);
132}
133
134/*
135 * Check the current frame sequence number against the current TID
136 * state and return whether it's in sequence or should be dropped.
137 *
138 * Since out of order packet and duplicate packet eliminations should
139 * be done by the AMPDU RX code, this routine blindly accepts all
140 * frames from a HT station w/ a TID that is currently doing AMPDU-RX.
141 * HT stations without WME or where the TID is not doing AMPDU-RX
142 * are checked like non-HT stations.
143 *
144 * The routine only eliminates packets whose sequence/fragment
145 * match or are less than the last seen sequence/fragment number
146 * AND are retransmits It doesn't try to eliminate out of order packets.
147 *
148 * Since all frames after sequence number 4095 will be less than 4095
149 * (as the seqnum wraps), handle that special case so packets aren't
150 * incorrectly dropped - ie, if the next packet is sequence number 0
151 * but a retransmit since the initial packet didn't make it.
152 */
153static __inline int
154ieee80211_check_rxseq(struct ieee80211_node *ni, struct ieee80211_frame *wh,
155    uint8_t *bssid)
156{
157#define	SEQ_LEQ(a,b)	((int)((a)-(b)) <= 0)
158#define	SEQ_EQ(a,b)	((int)((a)-(b)) == 0)
159#define	SEQNO(a)	((a) >> IEEE80211_SEQ_SEQ_SHIFT)
160#define	FRAGNO(a)	((a) & IEEE80211_SEQ_FRAG_MASK)
161	struct ieee80211vap *vap = ni->ni_vap;
162	uint16_t rxseq;
163	uint8_t type, subtype;
164	uint8_t tid;
165	struct ieee80211_rx_ampdu *rap;
166
167	rxseq = le16toh(*(uint16_t *)wh->i_seq);
168	type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
169	subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
170
171	/*
172	 * Types with no sequence number (or QoS (+)Null frames)
173	 * are always treated valid.
174	 */
175	if (! IEEE80211_HAS_SEQ(type, subtype))
176		return 1;
177
178	tid = ieee80211_gettid(wh);
179
180	/*
181	 * Only do the HT AMPDU check for WME stations; non-WME HT stations
182	 * shouldn't exist outside of debugging. We should at least
183	 * handle that.
184	 */
185	if (tid < WME_NUM_TID) {
186		rap = &ni->ni_rx_ampdu[tid];
187		/* HT nodes currently doing RX AMPDU are always valid */
188		if ((ni->ni_flags & IEEE80211_NODE_HT) &&
189		    (rap->rxa_flags & IEEE80211_AGGR_RUNNING))
190			goto ok;
191	}
192
193	/*
194	 * Otherwise, retries for packets below or equal to the last
195	 * seen sequence number should be dropped.
196	 */
197
198	/*
199	 * Treat frame seqnum 4095 as special due to boundary
200	 * wrapping conditions.
201	 */
202	if (SEQNO(ni->ni_rxseqs[tid]) == 4095) {
203		/*
204		 * Drop retransmits on seqnum 4095/current fragment for itself.
205		 */
206		if (SEQ_EQ(rxseq, ni->ni_rxseqs[tid]) &&
207		    (wh->i_fc[1] & IEEE80211_FC1_RETRY))
208			goto fail;
209		/*
210		 * Treat any subsequent frame as fine if the last seen frame
211		 * is 4095 and it's not a retransmit for the same sequence
212		 * number. However, this doesn't capture incorrectly ordered
213	 	 * fragments w/ sequence number 4095. It shouldn't be seen
214		 * in practice, but see the comment above for further info.
215		 */
216		goto ok;
217	}
218
219	/*
220	 * At this point we assume that retransmitted seq/frag numbers below
221	 * the current can simply be eliminated.
222	 */
223	if ((wh->i_fc[1] & IEEE80211_FC1_RETRY) &&
224	    SEQ_LEQ(rxseq, ni->ni_rxseqs[tid]))
225		goto fail;
226
227ok:
228	ni->ni_rxseqs[tid] = rxseq;
229
230	return 1;
231
232fail:
233	/* duplicate, discard */
234	IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT, bssid, "duplicate",
235	    "seqno <%u,%u> fragno <%u,%u> tid %u",
236	     SEQNO(rxseq),  SEQNO(ni->ni_rxseqs[tid]),
237	    FRAGNO(rxseq), FRAGNO(ni->ni_rxseqs[tid]), tid);
238	vap->iv_stats.is_rx_dup++;
239	IEEE80211_NODE_STAT(ni, rx_dup);
240
241	return 0;
242#undef	SEQ_LEQ
243#undef	SEQ_EQ
244#undef	SEQNO
245#undef	FRAGNO
246}
247
248void	ieee80211_deliver_data(struct ieee80211vap *,
249		struct ieee80211_node *, struct mbuf *);
250struct mbuf *ieee80211_defrag(struct ieee80211_node *,
251		struct mbuf *, int);
252struct mbuf *ieee80211_realign(struct ieee80211vap *, struct mbuf *, size_t);
253struct mbuf *ieee80211_decap(struct ieee80211vap *, struct mbuf *, int);
254struct mbuf *ieee80211_decap1(struct mbuf *, int *);
255int	ieee80211_setup_rates(struct ieee80211_node *ni,
256		const uint8_t *rates, const uint8_t *xrates, int flags);
257void ieee80211_send_error(struct ieee80211_node *,
258		const uint8_t mac[IEEE80211_ADDR_LEN], int subtype, int arg);
259int	ieee80211_alloc_challenge(struct ieee80211_node *);
260int	ieee80211_parse_beacon(struct ieee80211_node *, struct mbuf *,
261		struct ieee80211_channel *,
262		struct ieee80211_scanparams *);
263int	ieee80211_parse_action(struct ieee80211_node *, struct mbuf *);
264#endif /* _NET80211_IEEE80211_INPUT_H_ */
265