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1/* SPDX-License-Identifier: ((GPL-2.0-only WITH Linux-syscall-note) OR BSD-3-Clause) */2/*3 * linux/can/gw.h4 *5 * Definitions for CAN frame Gateway/Router/Bridge6 *7 * Author: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>8 * Copyright (c) 2011 Volkswagen Group Electronic Research9 * All rights reserved.10 *11 * Redistribution and use in source and binary forms, with or without12 * modification, are permitted provided that the following conditions13 * are met:14 * 1. Redistributions of source code must retain the above copyright15 * notice, this list of conditions and the following disclaimer.16 * 2. Redistributions in binary form must reproduce the above copyright17 * notice, this list of conditions and the following disclaimer in the18 * documentation and/or other materials provided with the distribution.19 * 3. Neither the name of Volkswagen nor the names of its contributors20 * may be used to endorse or promote products derived from this software21 * without specific prior written permission.22 *23 * Alternatively, provided that this notice is retained in full, this24 * software may be distributed under the terms of the GNU General25 * Public License ("GPL") version 2, in which case the provisions of the26 * GPL apply INSTEAD OF those given above.27 *28 * The provided data structures and external interfaces from this code29 * are not restricted to be used by modules with a GPL compatible license.30 *31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT35 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,36 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT37 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,38 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY39 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT40 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE41 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH42 * DAMAGE.43 */44 45#ifndef _UAPI_CAN_GW_H46#define _UAPI_CAN_GW_H47 48#include <linux/types.h>49#include <linux/can.h>50 51struct rtcanmsg {52 __u8 can_family;53 __u8 gwtype;54 __u16 flags;55};56 57/* CAN gateway types */58enum {59 CGW_TYPE_UNSPEC,60 CGW_TYPE_CAN_CAN, /* CAN->CAN routing */61 __CGW_TYPE_MAX62};63 64#define CGW_TYPE_MAX (__CGW_TYPE_MAX - 1)65 66/* CAN rtnetlink attribute definitions */67enum {68 CGW_UNSPEC,69 CGW_MOD_AND, /* CAN frame modification binary AND */70 CGW_MOD_OR, /* CAN frame modification binary OR */71 CGW_MOD_XOR, /* CAN frame modification binary XOR */72 CGW_MOD_SET, /* CAN frame modification set alternate values */73 CGW_CS_XOR, /* set data[] XOR checksum into data[index] */74 CGW_CS_CRC8, /* set data[] CRC8 checksum into data[index] */75 CGW_HANDLED, /* number of handled CAN frames */76 CGW_DROPPED, /* number of dropped CAN frames */77 CGW_SRC_IF, /* ifindex of source network interface */78 CGW_DST_IF, /* ifindex of destination network interface */79 CGW_FILTER, /* specify struct can_filter on source CAN device */80 CGW_DELETED, /* number of deleted CAN frames (see max_hops param) */81 CGW_LIM_HOPS, /* limit the number of hops of this specific rule */82 CGW_MOD_UID, /* user defined identifier for modification updates */83 CGW_FDMOD_AND, /* CAN FD frame modification binary AND */84 CGW_FDMOD_OR, /* CAN FD frame modification binary OR */85 CGW_FDMOD_XOR, /* CAN FD frame modification binary XOR */86 CGW_FDMOD_SET, /* CAN FD frame modification set alternate values */87 __CGW_MAX88};89 90#define CGW_MAX (__CGW_MAX - 1)91 92#define CGW_FLAGS_CAN_ECHO 0x0193#define CGW_FLAGS_CAN_SRC_TSTAMP 0x0294#define CGW_FLAGS_CAN_IIF_TX_OK 0x0495#define CGW_FLAGS_CAN_FD 0x0896 97#define CGW_MOD_FUNCS 4 /* AND OR XOR SET */98 99/* CAN frame elements that are affected by curr. 3 CAN frame modifications */100#define CGW_MOD_ID 0x01101#define CGW_MOD_DLC 0x02 /* Classical CAN data length code */102#define CGW_MOD_LEN CGW_MOD_DLC /* CAN FD (plain) data length */103#define CGW_MOD_DATA 0x04104#define CGW_MOD_FLAGS 0x08 /* CAN FD flags */105 106#define CGW_FRAME_MODS 4 /* ID DLC/LEN DATA FLAGS */107 108#define MAX_MODFUNCTIONS (CGW_MOD_FUNCS * CGW_FRAME_MODS)109 110struct cgw_frame_mod {111 struct can_frame cf;112 __u8 modtype;113} __attribute__((packed));114 115struct cgw_fdframe_mod {116 struct canfd_frame cf;117 __u8 modtype;118} __attribute__((packed));119 120#define CGW_MODATTR_LEN sizeof(struct cgw_frame_mod)121#define CGW_FDMODATTR_LEN sizeof(struct cgw_fdframe_mod)122 123struct cgw_csum_xor {124 __s8 from_idx;125 __s8 to_idx;126 __s8 result_idx;127 __u8 init_xor_val;128} __attribute__((packed));129 130struct cgw_csum_crc8 {131 __s8 from_idx;132 __s8 to_idx;133 __s8 result_idx;134 __u8 init_crc_val;135 __u8 final_xor_val;136 __u8 crctab[256];137 __u8 profile;138 __u8 profile_data[20];139} __attribute__((packed));140 141/* length of checksum operation parameters. idx = index in CAN frame data[] */142#define CGW_CS_XOR_LEN sizeof(struct cgw_csum_xor)143#define CGW_CS_CRC8_LEN sizeof(struct cgw_csum_crc8)144 145/* CRC8 profiles (compute CRC for additional data elements - see below) */146enum {147 CGW_CRC8PRF_UNSPEC,148 CGW_CRC8PRF_1U8, /* compute one additional u8 value */149 CGW_CRC8PRF_16U8, /* u8 value table indexed by data[1] & 0xF */150 CGW_CRC8PRF_SFFID_XOR, /* (can_id & 0xFF) ^ (can_id >> 8 & 0xFF) */151 __CGW_CRC8PRF_MAX152};153 154#define CGW_CRC8PRF_MAX (__CGW_CRC8PRF_MAX - 1)155 156/*157 * CAN rtnetlink attribute contents in detail158 *159 * CGW_XXX_IF (length 4 bytes):160 * Sets an interface index for source/destination network interfaces.161 * For the CAN->CAN gwtype the indices of _two_ CAN interfaces are mandatory.162 *163 * CGW_FILTER (length 8 bytes):164 * Sets a CAN receive filter for the gateway job specified by the165 * struct can_filter described in include/linux/can.h166 *167 * CGW_MOD_(AND|OR|XOR|SET) (length 17 bytes):168 * Specifies a modification that's done to a received CAN frame before it is169 * send out to the destination interface.170 *171 * <struct can_frame> data used as operator172 * <u8> affected CAN frame elements173 *174 * CGW_LIM_HOPS (length 1 byte):175 * Limit the number of hops of this specific rule. Usually the received CAN176 * frame can be processed as much as 'max_hops' times (which is given at module177 * load time of the can-gw module). This value is used to reduce the number of178 * possible hops for this gateway rule to a value smaller then max_hops.179 *180 * CGW_MOD_UID (length 4 bytes):181 * Optional non-zero user defined routing job identifier to alter existing182 * modification settings at runtime.183 *184 * CGW_CS_XOR (length 4 bytes):185 * Set a simple XOR checksum starting with an initial value into186 * data[result-idx] using data[start-idx] .. data[end-idx]187 *188 * The XOR checksum is calculated like this:189 *190 * xor = init_xor_val191 *192 * for (i = from_idx .. to_idx)193 * xor ^= can_frame.data[i]194 *195 * can_frame.data[ result_idx ] = xor196 *197 * CGW_CS_CRC8 (length 282 bytes):198 * Set a CRC8 value into data[result-idx] using a given 256 byte CRC8 table,199 * a given initial value and a defined input data[start-idx] .. data[end-idx].200 * Finally the result value is XOR'ed with the final_xor_val.201 *202 * The CRC8 checksum is calculated like this:203 *204 * crc = init_crc_val205 *206 * for (i = from_idx .. to_idx)207 * crc = crctab[ crc ^ can_frame.data[i] ]208 *209 * can_frame.data[ result_idx ] = crc ^ final_xor_val210 *211 * The calculated CRC may contain additional source data elements that can be212 * defined in the handling of 'checksum profiles' e.g. shown in AUTOSAR specs213 * like http://www.autosar.org/download/R4.0/AUTOSAR_SWS_E2ELibrary.pdf214 * E.g. the profile_data[] may contain additional u8 values (called DATA_IDs)215 * that are used depending on counter values inside the CAN frame data[].216 * So far only three profiles have been implemented for illustration.217 *218 * Remark: In general the attribute data is a linear buffer.219 * Beware of sending unpacked or aligned structs!220 */221 222#endif /* !_UAPI_CAN_GW_H */223