xref: /dragonfly/sys/netproto/802_11/ieee80211_input.h (revision 5f79922d05fe628a341acd558e7f0a4f90f49512)
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  * $FreeBSD$
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 %ld, expected %ld",        \
49                         (long)(_len), (long)(_minlen));                         \
50                     vap->iv_stats.is_rx_elem_toosmall++;                        \
51                     _action;                                                    \
52           }                                                                               \
53 } while (0)
54 
55 #ifdef IEEE80211_DEBUG
56 void      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 #include <sys/types.h>
84 
85 static __inline int
iswpaoui(const uint8_t * frm)86 iswpaoui(const uint8_t *frm)
87 {
88           return frm[1] > 3 && le32dec(frm+2) == ((WPA_OUI_TYPE<<24)|WPA_OUI);
89 }
90 
91 static __inline int
iswmeoui(const uint8_t * frm)92 iswmeoui(const uint8_t *frm)
93 {
94           return frm[1] > 3 && le32dec(frm+2) == ((WME_OUI_TYPE<<24)|WME_OUI);
95 }
96 
97 static __inline int
iswmeparam(const uint8_t * frm)98 iswmeparam(const uint8_t *frm)
99 {
100           return frm[1] > 5 && le32dec(frm+2) == ((WME_OUI_TYPE<<24)|WME_OUI) &&
101                     frm[6] == WME_PARAM_OUI_SUBTYPE;
102 }
103 
104 static __inline int
iswmeinfo(const uint8_t * frm)105 iswmeinfo(const uint8_t *frm)
106 {
107           return frm[1] > 5 && le32dec(frm+2) == ((WME_OUI_TYPE<<24)|WME_OUI) &&
108                     frm[6] == WME_INFO_OUI_SUBTYPE;
109 }
110 
111 static __inline int
isatherosoui(const uint8_t * frm)112 isatherosoui(const uint8_t *frm)
113 {
114           return frm[1] > 3 && le32dec(frm+2) == ((ATH_OUI_TYPE<<24)|ATH_OUI);
115 }
116 
117 static __inline int
istdmaoui(const uint8_t * frm)118 istdmaoui(const uint8_t *frm)
119 {
120           return frm[1] > 3 && le32dec(frm+2) == ((TDMA_OUI_TYPE<<24)|TDMA_OUI);
121 }
122 
123 static __inline int
ishtcapoui(const uint8_t * frm)124 ishtcapoui(const uint8_t *frm)
125 {
126           return frm[1] > 3 && le32dec(frm+2) == ((BCM_OUI_HTCAP<<24)|BCM_OUI);
127 }
128 
129 static __inline int
ishtinfooui(const uint8_t * frm)130 ishtinfooui(const uint8_t *frm)
131 {
132           return frm[1] > 3 && le32dec(frm+2) == ((BCM_OUI_HTINFO<<24)|BCM_OUI);
133 }
134 
135 /*
136  * Check the current frame sequence number against the current TID
137  * state and return whether it's in sequence or should be dropped.
138  *
139  * Since out of order packet and duplicate packet eliminations should
140  * be done by the AMPDU RX code, this routine blindly accepts all
141  * frames from a HT station w/ a TID that is currently doing AMPDU-RX.
142  * HT stations without WME or where the TID is not doing AMPDU-RX
143  * are checked like non-HT stations.
144  *
145  * The routine only eliminates packets whose sequence/fragment
146  * match or are less than the last seen sequence/fragment number
147  * AND are retransmits It doesn't try to eliminate out of order packets.
148  *
149  * Since all frames after sequence number 4095 will be less than 4095
150  * (as the seqnum wraps), handle that special case so packets aren't
151  * incorrectly dropped - ie, if the next packet is sequence number 0
152  * but a retransmit since the initial packet didn't make it.
153  */
154 static __inline int
ieee80211_check_rxseq(struct ieee80211_node * ni,struct ieee80211_frame * wh,uint8_t * bssid)155 ieee80211_check_rxseq(struct ieee80211_node *ni, struct ieee80211_frame *wh,
156     uint8_t *bssid)
157 {
158 #define   SEQ_LEQ(a,b)        ((int)((a)-(b)) <= 0)
159 #define   SEQ_EQ(a,b)         ((int)((a)-(b)) == 0)
160 #define   SEQNO(a)  ((a) >> IEEE80211_SEQ_SEQ_SHIFT)
161 #define   FRAGNO(a) ((a) & IEEE80211_SEQ_FRAG_MASK)
162           struct ieee80211vap *vap = ni->ni_vap;
163           uint16_t rxseq;
164           uint8_t type, subtype;
165           uint8_t tid;
166           struct ieee80211_rx_ampdu *rap;
167 
168           rxseq = le16toh(*(uint16_t *)wh->i_seq);
169           type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
170           subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
171 
172           /*
173            * Types with no sequence number (or QoS (+)Null frames)
174            * are always treated valid.
175            */
176           if (! IEEE80211_HAS_SEQ(type, subtype))
177                     return 1;
178 
179           tid = ieee80211_gettid(wh);
180 
181           /*
182            * Only do the HT AMPDU check for WME stations; non-WME HT stations
183            * shouldn't exist outside of debugging. We should at least
184            * handle that.
185            */
186           if (tid < WME_NUM_TID) {
187                     rap = &ni->ni_rx_ampdu[tid];
188                     /* HT nodes currently doing RX AMPDU are always valid */
189                     if ((ni->ni_flags & IEEE80211_NODE_HT) &&
190                         (rap->rxa_flags & IEEE80211_AGGR_RUNNING))
191                               goto ok;
192           }
193 
194           /*
195            * Otherwise, retries for packets below or equal to the last
196            * seen sequence number should be dropped.
197            */
198 
199           /*
200            * Treat frame seqnum 4095 as special due to boundary
201            * wrapping conditions.
202            */
203           if (SEQNO(ni->ni_rxseqs[tid]) == 4095) {
204                     /*
205                      * Drop retransmits on seqnum 4095/current fragment for itself.
206                      */
207                     if (SEQ_EQ(rxseq, ni->ni_rxseqs[tid]) &&
208                         (wh->i_fc[1] & IEEE80211_FC1_RETRY))
209                               goto fail;
210                     /*
211                      * Treat any subsequent frame as fine if the last seen frame
212                      * is 4095 and it's not a retransmit for the same sequence
213                      * number. However, this doesn't capture incorrectly ordered
214                      * fragments w/ sequence number 4095. It shouldn't be seen
215                      * in practice, but see the comment above for further info.
216                      */
217                     goto ok;
218           }
219 
220           /*
221            * At this point we assume that retransmitted seq/frag numbers below
222            * the current can simply be eliminated.
223            */
224           if ((wh->i_fc[1] & IEEE80211_FC1_RETRY) &&
225               SEQ_LEQ(rxseq, ni->ni_rxseqs[tid]))
226                     goto fail;
227 
228 ok:
229           ni->ni_rxseqs[tid] = rxseq;
230 
231           return 1;
232 
233 fail:
234           /* duplicate, discard */
235           IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT, bssid, "duplicate",
236               "seqno <%u,%u> fragno <%u,%u> tid %u",
237                SEQNO(rxseq),  SEQNO(ni->ni_rxseqs[tid]),
238               FRAGNO(rxseq), FRAGNO(ni->ni_rxseqs[tid]), tid);
239           vap->iv_stats.is_rx_dup++;
240           IEEE80211_NODE_STAT(ni, rx_dup);
241 
242           return 0;
243 #undef    SEQ_LEQ
244 #undef    SEQ_EQ
245 #undef    SEQNO
246 #undef    FRAGNO
247 }
248 
249 void      ieee80211_deliver_data(struct ieee80211vap *,
250                     struct ieee80211_node *, struct mbuf *);
251 struct mbuf *ieee80211_defrag(struct ieee80211_node *,
252                     struct mbuf *, int);
253 struct mbuf *ieee80211_realign(struct ieee80211vap *, struct mbuf *, size_t);
254 struct mbuf *ieee80211_decap(struct ieee80211vap *, struct mbuf *, int);
255 struct mbuf *ieee80211_decap1(struct mbuf *, int *);
256 int       ieee80211_setup_rates(struct ieee80211_node *ni,
257                     const uint8_t *rates, const uint8_t *xrates, int flags);
258 void ieee80211_send_error(struct ieee80211_node *,
259                     const uint8_t mac[IEEE80211_ADDR_LEN], int subtype, int arg);
260 int       ieee80211_alloc_challenge(struct ieee80211_node *);
261 int       ieee80211_parse_beacon(struct ieee80211_node *, struct mbuf *,
262                     struct ieee80211_channel *,
263                     struct ieee80211_scanparams *);
264 int       ieee80211_parse_action(struct ieee80211_node *, struct mbuf *);
265 #endif /* _NET80211_IEEE80211_INPUT_H_ */
266