1 /* SPDX-License-Identifier: (GPL-2.0 OR MPL-1.1) */ 2 /* 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 * -------------------------------------------------------------------- 12 * 13 * Inquiries regarding the linux-wlan Open Source project can be 14 * made directly to: 15 * 16 * AbsoluteValue Systems Inc. 17 * info@linux-wlan.com 18 * http://www.linux-wlan.com 19 * 20 * -------------------------------------------------------------------- 21 * 22 * Portions of the development of this software were funded by 23 * Intersil Corporation as part of PRISM(R) chipset product development. 24 * 25 * -------------------------------------------------------------------- 26 * 27 * This file declares the constants and types used in the interface 28 * between a wlan driver and the user mode utilities. 29 * 30 * Note: 31 * - Constant values are always in HOST byte order. To assign 32 * values to multi-byte fields they _must_ be converted to 33 * ieee byte order. To retrieve multi-byte values from incoming 34 * frames, they must be converted to host order. 35 * 36 * All functions declared here are implemented in p80211.c 37 * -------------------------------------------------------------------- 38 */ 39 40 #ifndef _P80211HDR_H 41 #define _P80211HDR_H 42 43 #include <linux/if_ether.h> 44 45 /*--- Sizes -----------------------------------------------*/ 46 #define WLAN_CRC_LEN 4 47 #define WLAN_BSSID_LEN 6 48 #define WLAN_HDR_A3_LEN 24 49 #define WLAN_HDR_A4_LEN 30 50 #define WLAN_SSID_MAXLEN 32 51 #define WLAN_DATA_MAXLEN 2312 52 #define WLAN_WEP_IV_LEN 4 53 #define WLAN_WEP_ICV_LEN 4 54 55 /*--- Frame Control Field -------------------------------------*/ 56 /* Frame Types */ 57 #define WLAN_FTYPE_MGMT 0x00 58 #define WLAN_FTYPE_CTL 0x01 59 #define WLAN_FTYPE_DATA 0x02 60 61 /* Frame subtypes */ 62 /* Management */ 63 #define WLAN_FSTYPE_ASSOCREQ 0x00 64 #define WLAN_FSTYPE_ASSOCRESP 0x01 65 #define WLAN_FSTYPE_REASSOCREQ 0x02 66 #define WLAN_FSTYPE_REASSOCRESP 0x03 67 #define WLAN_FSTYPE_PROBEREQ 0x04 68 #define WLAN_FSTYPE_PROBERESP 0x05 69 #define WLAN_FSTYPE_BEACON 0x08 70 #define WLAN_FSTYPE_ATIM 0x09 71 #define WLAN_FSTYPE_DISASSOC 0x0a 72 #define WLAN_FSTYPE_AUTHEN 0x0b 73 #define WLAN_FSTYPE_DEAUTHEN 0x0c 74 75 /* Control */ 76 #define WLAN_FSTYPE_BLOCKACKREQ 0x8 77 #define WLAN_FSTYPE_BLOCKACK 0x9 78 #define WLAN_FSTYPE_PSPOLL 0x0a 79 #define WLAN_FSTYPE_RTS 0x0b 80 #define WLAN_FSTYPE_CTS 0x0c 81 #define WLAN_FSTYPE_ACK 0x0d 82 #define WLAN_FSTYPE_CFEND 0x0e 83 #define WLAN_FSTYPE_CFENDCFACK 0x0f 84 85 /* Data */ 86 #define WLAN_FSTYPE_DATAONLY 0x00 87 #define WLAN_FSTYPE_DATA_CFACK 0x01 88 #define WLAN_FSTYPE_DATA_CFPOLL 0x02 89 #define WLAN_FSTYPE_DATA_CFACK_CFPOLL 0x03 90 #define WLAN_FSTYPE_NULL 0x04 91 #define WLAN_FSTYPE_CFACK 0x05 92 #define WLAN_FSTYPE_CFPOLL 0x06 93 #define WLAN_FSTYPE_CFACK_CFPOLL 0x07 94 95 /*--- FC Macros ----------------------------------------------*/ 96 /* Macros to get/set the bitfields of the Frame Control Field */ 97 /* GET_FC_??? - takes the host byte-order value of an FC */ 98 /* and retrieves the value of one of the */ 99 /* bitfields and moves that value so its lsb is */ 100 /* in bit 0. */ 101 /* SET_FC_??? - takes a host order value for one of the FC */ 102 /* bitfields and moves it to the proper bit */ 103 /* location for ORing into a host order FC. */ 104 /* To send the FC produced from SET_FC_???, */ 105 /* one must put the bytes in IEEE order. */ 106 /* e.g. */ 107 /* printf("the frame subtype is %x", */ 108 /* GET_FC_FTYPE( ieee2host( rx.fc ))) */ 109 /* */ 110 /* tx.fc = host2ieee( SET_FC_FTYPE(WLAN_FTYP_CTL) | */ 111 /* SET_FC_FSTYPE(WLAN_FSTYPE_RTS) ); */ 112 /*------------------------------------------------------------*/ 113 114 #define WLAN_GET_FC_FTYPE(n) ((((u16)(n)) & GENMASK(3, 2)) >> 2) 115 #define WLAN_GET_FC_FSTYPE(n) ((((u16)(n)) & GENMASK(7, 4)) >> 4) 116 #define WLAN_GET_FC_TODS(n) ((((u16)(n)) & (BIT(8))) >> 8) 117 #define WLAN_GET_FC_FROMDS(n) ((((u16)(n)) & (BIT(9))) >> 9) 118 #define WLAN_GET_FC_ISWEP(n) ((((u16)(n)) & (BIT(14))) >> 14) 119 120 #define WLAN_SET_FC_FTYPE(n) (((u16)(n)) << 2) 121 #define WLAN_SET_FC_FSTYPE(n) (((u16)(n)) << 4) 122 #define WLAN_SET_FC_TODS(n) (((u16)(n)) << 8) 123 #define WLAN_SET_FC_FROMDS(n) (((u16)(n)) << 9) 124 #define WLAN_SET_FC_ISWEP(n) (((u16)(n)) << 14) 125 126 #define DOT11_RATE5_ISBASIC_GET(r) (((u8)(r)) & BIT(7)) 127 128 /* Generic 802.11 Header types */ 129 130 struct p80211_hdr { 131 __le16 frame_control; 132 u16 duration_id; 133 u8 address1[ETH_ALEN]; 134 u8 address2[ETH_ALEN]; 135 u8 address3[ETH_ALEN]; 136 u16 sequence_control; 137 u8 address4[ETH_ALEN]; 138 } __packed; 139 140 /* Frame and header length macros */ 141 wlan_ctl_framelen(u16 fstype)142static inline u16 wlan_ctl_framelen(u16 fstype) 143 { 144 switch (fstype) { 145 case WLAN_FSTYPE_BLOCKACKREQ: 146 return 24; 147 case WLAN_FSTYPE_BLOCKACK: 148 return 152; 149 case WLAN_FSTYPE_PSPOLL: 150 case WLAN_FSTYPE_RTS: 151 case WLAN_FSTYPE_CFEND: 152 case WLAN_FSTYPE_CFENDCFACK: 153 return 20; 154 case WLAN_FSTYPE_CTS: 155 case WLAN_FSTYPE_ACK: 156 return 14; 157 default: 158 return 4; 159 } 160 } 161 162 #define WLAN_FCS_LEN 4 163 164 /* ftcl in HOST order */ p80211_headerlen(u16 fctl)165static inline u16 p80211_headerlen(u16 fctl) 166 { 167 u16 hdrlen = 0; 168 169 switch (WLAN_GET_FC_FTYPE(fctl)) { 170 case WLAN_FTYPE_MGMT: 171 hdrlen = WLAN_HDR_A3_LEN; 172 break; 173 case WLAN_FTYPE_DATA: 174 hdrlen = WLAN_HDR_A3_LEN; 175 if (WLAN_GET_FC_TODS(fctl) && WLAN_GET_FC_FROMDS(fctl)) 176 hdrlen += ETH_ALEN; 177 break; 178 case WLAN_FTYPE_CTL: 179 hdrlen = wlan_ctl_framelen(WLAN_GET_FC_FSTYPE(fctl)) - 180 WLAN_FCS_LEN; 181 break; 182 default: 183 hdrlen = WLAN_HDR_A3_LEN; 184 } 185 186 return hdrlen; 187 } 188 189 #endif /* _P80211HDR_H */ 190