1 /* SPDX-License-Identifier: ((GPL-2.0-only WITH Linux-syscall-note) OR BSD-3-Clause) */ 2 /* 3 * linux/can/isotp.h 4 * 5 * Definitions for isotp CAN sockets (ISO 15765-2:2016) 6 * 7 * Copyright (c) 2020 Volkswagen Group Electronic Research 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of Volkswagen nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * Alternatively, provided that this notice is retained in full, this 23 * software may be distributed under the terms of the GNU General 24 * Public License ("GPL") version 2, in which case the provisions of the 25 * GPL apply INSTEAD OF those given above. 26 * 27 * The provided data structures and external interfaces from this code 28 * are not restricted to be used by modules with a GPL compatible license. 29 * 30 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 31 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 32 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 33 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 34 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 35 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 36 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 37 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 38 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 39 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 40 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 41 * DAMAGE. 42 */ 43 44 #ifndef _UAPI_CAN_ISOTP_H 45 #define _UAPI_CAN_ISOTP_H 46 47 #include <linux/types.h> 48 #include <linux/can.h> 49 50 #define SOL_CAN_ISOTP (SOL_CAN_BASE + CAN_ISOTP) 51 52 /* for socket options affecting the socket (not the global system) */ 53 54 #define CAN_ISOTP_OPTS 1 /* pass struct can_isotp_options */ 55 56 #define CAN_ISOTP_RECV_FC 2 /* pass struct can_isotp_fc_options */ 57 58 /* sockopts to force stmin timer values for protocol regression tests */ 59 60 #define CAN_ISOTP_TX_STMIN 3 /* pass __u32 value in nano secs */ 61 /* use this time instead of value */ 62 /* provided in FC from the receiver */ 63 64 #define CAN_ISOTP_RX_STMIN 4 /* pass __u32 value in nano secs */ 65 /* ignore received CF frames which */ 66 /* timestamps differ less than val */ 67 68 #define CAN_ISOTP_LL_OPTS 5 /* pass struct can_isotp_ll_options */ 69 70 struct can_isotp_options { 71 72 __u32 flags; /* set flags for isotp behaviour. */ 73 /* __u32 value : flags see below */ 74 75 __u32 frame_txtime; /* frame transmission time (N_As/N_Ar) */ 76 /* __u32 value : time in nano secs */ 77 78 __u8 ext_address; /* set address for extended addressing */ 79 /* __u8 value : extended address */ 80 81 __u8 txpad_content; /* set content of padding byte (tx) */ 82 /* __u8 value : content on tx path */ 83 84 __u8 rxpad_content; /* set content of padding byte (rx) */ 85 /* __u8 value : content on rx path */ 86 87 __u8 rx_ext_address; /* set address for extended addressing */ 88 /* __u8 value : extended address (rx) */ 89 }; 90 91 struct can_isotp_fc_options { 92 93 __u8 bs; /* blocksize provided in FC frame */ 94 /* __u8 value : blocksize. 0 = off */ 95 96 __u8 stmin; /* separation time provided in FC frame */ 97 /* __u8 value : */ 98 /* 0x00 - 0x7F : 0 - 127 ms */ 99 /* 0x80 - 0xF0 : reserved */ 100 /* 0xF1 - 0xF9 : 100 us - 900 us */ 101 /* 0xFA - 0xFF : reserved */ 102 103 __u8 wftmax; /* max. number of wait frame transmiss. */ 104 /* __u8 value : 0 = omit FC N_PDU WT */ 105 }; 106 107 struct can_isotp_ll_options { 108 109 __u8 mtu; /* generated & accepted CAN frame type */ 110 /* __u8 value : */ 111 /* CAN_MTU (16) -> standard CAN 2.0 */ 112 /* CANFD_MTU (72) -> CAN FD frame */ 113 114 __u8 tx_dl; /* tx link layer data length in bytes */ 115 /* (configured maximum payload length) */ 116 /* __u8 value : 8,12,16,20,24,32,48,64 */ 117 /* => rx path supports all LL_DL values */ 118 119 __u8 tx_flags; /* set into struct canfd_frame.flags */ 120 /* at frame creation: e.g. CANFD_BRS */ 121 /* Obsolete when the BRS flag is fixed */ 122 /* by the CAN netdriver configuration */ 123 }; 124 125 /* flags for isotp behaviour */ 126 127 #define CAN_ISOTP_LISTEN_MODE 0x0001 /* listen only (do not send FC) */ 128 #define CAN_ISOTP_EXTEND_ADDR 0x0002 /* enable extended addressing */ 129 #define CAN_ISOTP_TX_PADDING 0x0004 /* enable CAN frame padding tx path */ 130 #define CAN_ISOTP_RX_PADDING 0x0008 /* enable CAN frame padding rx path */ 131 #define CAN_ISOTP_CHK_PAD_LEN 0x0010 /* check received CAN frame padding */ 132 #define CAN_ISOTP_CHK_PAD_DATA 0x0020 /* check received CAN frame padding */ 133 #define CAN_ISOTP_HALF_DUPLEX 0x0040 /* half duplex error state handling */ 134 #define CAN_ISOTP_FORCE_TXSTMIN 0x0080 /* ignore stmin from received FC */ 135 #define CAN_ISOTP_FORCE_RXSTMIN 0x0100 /* ignore CFs depending on rx stmin */ 136 #define CAN_ISOTP_RX_EXT_ADDR 0x0200 /* different rx extended addressing */ 137 #define CAN_ISOTP_WAIT_TX_DONE 0x0400 /* wait for tx completion */ 138 #define CAN_ISOTP_SF_BROADCAST 0x0800 /* 1-to-N functional addressing */ 139 #define CAN_ISOTP_CF_BROADCAST 0x1000 /* 1-to-N transmission w/o FC */ 140 #define CAN_ISOTP_DYN_FC_PARMS 0x2000 /* dynamic FC parameters BS/STmin */ 141 142 /* protocol machine default values */ 143 144 #define CAN_ISOTP_DEFAULT_FLAGS 0 145 #define CAN_ISOTP_DEFAULT_EXT_ADDRESS 0x00 146 #define CAN_ISOTP_DEFAULT_PAD_CONTENT 0xCC /* prevent bit-stuffing */ 147 #define CAN_ISOTP_DEFAULT_FRAME_TXTIME 50000 /* 50 micro seconds */ 148 #define CAN_ISOTP_DEFAULT_RECV_BS 0 149 #define CAN_ISOTP_DEFAULT_RECV_STMIN 0x00 150 #define CAN_ISOTP_DEFAULT_RECV_WFTMAX 0 151 152 /* 153 * Remark on CAN_ISOTP_DEFAULT_RECV_* values: 154 * 155 * We can strongly assume, that the Linux Kernel implementation of 156 * CAN_ISOTP is capable to run with BS=0, STmin=0 and WFTmax=0. 157 * But as we like to be able to behave as a commonly available ECU, 158 * these default settings can be changed via sockopts. 159 * For that reason the STmin value is intentionally _not_ checked for 160 * consistency and copied directly into the flow control (FC) frame. 161 */ 162 163 /* link layer default values => make use of Classical CAN frames */ 164 165 #define CAN_ISOTP_DEFAULT_LL_MTU CAN_MTU 166 #define CAN_ISOTP_DEFAULT_LL_TX_DL CAN_MAX_DLEN 167 #define CAN_ISOTP_DEFAULT_LL_TX_FLAGS 0 168 169 /* 170 * The CAN_ISOTP_DEFAULT_FRAME_TXTIME has become a non-zero value as 171 * it only makes sense for isotp implementation tests to run without 172 * a N_As value. As user space applications usually do not set the 173 * frame_txtime element of struct can_isotp_options the new in-kernel 174 * default is very likely overwritten with zero when the sockopt() 175 * CAN_ISOTP_OPTS is invoked. 176 * To make sure that a N_As value of zero is only set intentional the 177 * value '0' is now interpreted as 'do not change the current value'. 178 * When a frame_txtime of zero is required for testing purposes this 179 * CAN_ISOTP_FRAME_TXTIME_ZERO u32 value has to be set in frame_txtime. 180 */ 181 #define CAN_ISOTP_FRAME_TXTIME_ZERO 0xFFFFFFFF 182 183 #endif /* !_UAPI_CAN_ISOTP_H */ 184