1 /* SPDX-License-Identifier: (GPL-2.0 OR MPL-1.1) */
2 /* p80211hdr.h
3 *
4 * Macros, types, and functions for handling 802.11 MAC headers
5 *
6 * Copyright (C) 1999 AbsoluteValue Systems, Inc. All Rights Reserved.
7 * --------------------------------------------------------------------
8 *
9 * linux-wlan
10 *
11 * The contents of this file are subject to the Mozilla Public
12 * License Version 1.1 (the "License"); you may not use this file
13 * except in compliance with the License. You may obtain a copy of
14 * the License at http://www.mozilla.org/MPL/
15 *
16 * Software distributed under the License is distributed on an "AS
17 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
18 * implied. See the License for the specific language governing
19 * rights and limitations under the License.
20 *
21 * Alternatively, the contents of this file may be used under the
22 * terms of the GNU Public License version 2 (the "GPL"), in which
23 * case the provisions of the GPL are applicable instead of the
24 * above. If you wish to allow the use of your version of this file
25 * only under the terms of the GPL and not to allow others to use
26 * your version of this file under the MPL, indicate your decision
27 * by deleting the provisions above and replace them with the notice
28 * and other provisions required by the GPL. If you do not delete
29 * the provisions above, a recipient may use your version of this
30 * file under either the MPL or the GPL.
31 *
32 * --------------------------------------------------------------------
33 *
34 * Inquiries regarding the linux-wlan Open Source project can be
35 * made directly to:
36 *
37 * AbsoluteValue Systems Inc.
38 * info@linux-wlan.com
39 * http://www.linux-wlan.com
40 *
41 * --------------------------------------------------------------------
42 *
43 * Portions of the development of this software were funded by
44 * Intersil Corporation as part of PRISM(R) chipset product development.
45 *
46 * --------------------------------------------------------------------
47 *
48 * This file declares the constants and types used in the interface
49 * between a wlan driver and the user mode utilities.
50 *
51 * Note:
52 * - Constant values are always in HOST byte order. To assign
53 * values to multi-byte fields they _must_ be converted to
54 * ieee byte order. To retrieve multi-byte values from incoming
55 * frames, they must be converted to host order.
56 *
57 * All functions declared here are implemented in p80211.c
58 * --------------------------------------------------------------------
59 */
60
61 #ifndef _P80211HDR_H
62 #define _P80211HDR_H
63
64 #include <linux/if_ether.h>
65
66 /*--- Sizes -----------------------------------------------*/
67 #define WLAN_CRC_LEN 4
68 #define WLAN_BSSID_LEN 6
69 #define WLAN_HDR_A3_LEN 24
70 #define WLAN_HDR_A4_LEN 30
71 #define WLAN_SSID_MAXLEN 32
72 #define WLAN_DATA_MAXLEN 2312
73 #define WLAN_WEP_IV_LEN 4
74 #define WLAN_WEP_ICV_LEN 4
75
76 /*--- Frame Control Field -------------------------------------*/
77 /* Frame Types */
78 #define WLAN_FTYPE_MGMT 0x00
79 #define WLAN_FTYPE_CTL 0x01
80 #define WLAN_FTYPE_DATA 0x02
81
82 /* Frame subtypes */
83 /* Management */
84 #define WLAN_FSTYPE_ASSOCREQ 0x00
85 #define WLAN_FSTYPE_ASSOCRESP 0x01
86 #define WLAN_FSTYPE_REASSOCREQ 0x02
87 #define WLAN_FSTYPE_REASSOCRESP 0x03
88 #define WLAN_FSTYPE_PROBEREQ 0x04
89 #define WLAN_FSTYPE_PROBERESP 0x05
90 #define WLAN_FSTYPE_BEACON 0x08
91 #define WLAN_FSTYPE_ATIM 0x09
92 #define WLAN_FSTYPE_DISASSOC 0x0a
93 #define WLAN_FSTYPE_AUTHEN 0x0b
94 #define WLAN_FSTYPE_DEAUTHEN 0x0c
95
96 /* Control */
97 #define WLAN_FSTYPE_BLOCKACKREQ 0x8
98 #define WLAN_FSTYPE_BLOCKACK 0x9
99 #define WLAN_FSTYPE_PSPOLL 0x0a
100 #define WLAN_FSTYPE_RTS 0x0b
101 #define WLAN_FSTYPE_CTS 0x0c
102 #define WLAN_FSTYPE_ACK 0x0d
103 #define WLAN_FSTYPE_CFEND 0x0e
104 #define WLAN_FSTYPE_CFENDCFACK 0x0f
105
106 /* Data */
107 #define WLAN_FSTYPE_DATAONLY 0x00
108 #define WLAN_FSTYPE_DATA_CFACK 0x01
109 #define WLAN_FSTYPE_DATA_CFPOLL 0x02
110 #define WLAN_FSTYPE_DATA_CFACK_CFPOLL 0x03
111 #define WLAN_FSTYPE_NULL 0x04
112 #define WLAN_FSTYPE_CFACK 0x05
113 #define WLAN_FSTYPE_CFPOLL 0x06
114 #define WLAN_FSTYPE_CFACK_CFPOLL 0x07
115
116 /*--- FC Macros ----------------------------------------------*/
117 /* Macros to get/set the bitfields of the Frame Control Field */
118 /* GET_FC_??? - takes the host byte-order value of an FC */
119 /* and retrieves the value of one of the */
120 /* bitfields and moves that value so its lsb is */
121 /* in bit 0. */
122 /* SET_FC_??? - takes a host order value for one of the FC */
123 /* bitfields and moves it to the proper bit */
124 /* location for ORing into a host order FC. */
125 /* To send the FC produced from SET_FC_???, */
126 /* one must put the bytes in IEEE order. */
127 /* e.g. */
128 /* printf("the frame subtype is %x", */
129 /* GET_FC_FTYPE( ieee2host( rx.fc ))) */
130 /* */
131 /* tx.fc = host2ieee( SET_FC_FTYPE(WLAN_FTYP_CTL) | */
132 /* SET_FC_FSTYPE(WLAN_FSTYPE_RTS) ); */
133 /*------------------------------------------------------------*/
134
135 #define WLAN_GET_FC_FTYPE(n) ((((u16)(n)) & GENMASK(3, 2)) >> 2)
136 #define WLAN_GET_FC_FSTYPE(n) ((((u16)(n)) & GENMASK(7, 4)) >> 4)
137 #define WLAN_GET_FC_TODS(n) ((((u16)(n)) & (BIT(8))) >> 8)
138 #define WLAN_GET_FC_FROMDS(n) ((((u16)(n)) & (BIT(9))) >> 9)
139 #define WLAN_GET_FC_ISWEP(n) ((((u16)(n)) & (BIT(14))) >> 14)
140
141 #define WLAN_SET_FC_FTYPE(n) (((u16)(n)) << 2)
142 #define WLAN_SET_FC_FSTYPE(n) (((u16)(n)) << 4)
143 #define WLAN_SET_FC_TODS(n) (((u16)(n)) << 8)
144 #define WLAN_SET_FC_FROMDS(n) (((u16)(n)) << 9)
145 #define WLAN_SET_FC_ISWEP(n) (((u16)(n)) << 14)
146
147 #define DOT11_RATE5_ISBASIC_GET(r) (((u8)(r)) & BIT(7))
148
149 /* Generic 802.11 Header types */
150
151 struct p80211_hdr_a3 {
152 __le16 fc;
153 u16 dur;
154 u8 a1[ETH_ALEN];
155 u8 a2[ETH_ALEN];
156 u8 a3[ETH_ALEN];
157 u16 seq;
158 } __packed;
159
160 struct p80211_hdr_a4 {
161 u16 fc;
162 u16 dur;
163 u8 a1[ETH_ALEN];
164 u8 a2[ETH_ALEN];
165 u8 a3[ETH_ALEN];
166 u16 seq;
167 u8 a4[ETH_ALEN];
168 } __packed;
169
170 union p80211_hdr {
171 struct p80211_hdr_a3 a3;
172 struct p80211_hdr_a4 a4;
173 } __packed;
174
175 /* Frame and header length macros */
176
177 static inline u16 wlan_ctl_framelen(u16 fstype)
178 {
179 switch (fstype) {
180 case WLAN_FSTYPE_BLOCKACKREQ:
181 return 24;
182 case WLAN_FSTYPE_BLOCKACK:
183 return 152;
184 case WLAN_FSTYPE_PSPOLL:
185 case WLAN_FSTYPE_RTS:
186 case WLAN_FSTYPE_CFEND:
187 case WLAN_FSTYPE_CFENDCFACK:
188 return 20;
189 case WLAN_FSTYPE_CTS:
190 case WLAN_FSTYPE_ACK:
191 return 14;
192 default:
193 return 4;
194 }
195 }
196
197 #define WLAN_FCS_LEN 4
198
199 /* ftcl in HOST order */
200 static inline u16 p80211_headerlen(u16 fctl)
201 {
202 u16 hdrlen = 0;
203
204 switch (WLAN_GET_FC_FTYPE(fctl)) {
205 case WLAN_FTYPE_MGMT:
206 hdrlen = WLAN_HDR_A3_LEN;
207 break;
208 case WLAN_FTYPE_DATA:
209 hdrlen = WLAN_HDR_A3_LEN;
210 if (WLAN_GET_FC_TODS(fctl) && WLAN_GET_FC_FROMDS(fctl))
211 hdrlen += ETH_ALEN;
212 break;
213 case WLAN_FTYPE_CTL:
214 hdrlen = wlan_ctl_framelen(WLAN_GET_FC_FSTYPE(fctl)) -
215 WLAN_FCS_LEN;
216 break;
217 default:
218 hdrlen = WLAN_HDR_A3_LEN;
219 }
220
221 return hdrlen;
222 }
223
224 #endif /* _P80211HDR_H */