1/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Global definitions for the ARCnet interface.
8 *
9 * Authors: David Woodhouse and Avery Pennarun
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version
14 * 2 of the License, or (at your option) any later version.
15 */
16
17#ifndef _LINUX_IF_ARCNET_H
18#define _LINUX_IF_ARCNET_H
19
20#include <linux/types.h>
21#include <linux/if_ether.h>
22
23/*
24 * These are the defined ARCnet Protocol ID's.
25 */
26
27/* CAP mode */
28/* No macro but uses 1-8 */
29
30/* RFC1201 Protocol ID's */
31#define ARC_P_IP 212 /* 0xD4 */
32#define ARC_P_IPV6 196 /* 0xC4: RFC2497 */
33#define ARC_P_ARP 213 /* 0xD5 */
34#define ARC_P_RARP 214 /* 0xD6 */
35#define ARC_P_IPX 250 /* 0xFA */
36#define ARC_P_NOVELL_EC 236 /* 0xEC */
37
38/* Old RFC1051 Protocol ID's */
39#define ARC_P_IP_RFC1051 240 /* 0xF0 */
40#define ARC_P_ARP_RFC1051 241 /* 0xF1 */
41
42/* MS LanMan/WfWg "NDIS" encapsulation */
43#define ARC_P_ETHER 232 /* 0xE8 */
44
45/* Unsupported/indirectly supported protocols */
46#define ARC_P_DATAPOINT_BOOT 0 /* very old Datapoint equipment */
47#define ARC_P_DATAPOINT_MOUNT 1
48#define ARC_P_POWERLAN_BEACON 8 /* Probably ATA-Netbios related */
49#define ARC_P_POWERLAN_BEACON2 243 /* 0xF3 */
50#define ARC_P_LANSOFT 251 /* 0xFB - what is this? */
51#define ARC_P_ATALK 0xDD
52
53/* Hardware address length */
54#define ARCNET_ALEN 1
55
56/*
57 * The RFC1201-specific components of an arcnet packet header.
58 */
59struct arc_rfc1201 {
60 __u8 proto; /* protocol ID field - varies */
61 __u8 split_flag; /* for use with split packets */
62 __be16 sequence; /* sequence number */
63 __u8 payload[]; /* space remaining in packet (504 bytes)*/
64};
65#define RFC1201_HDR_SIZE 4
66
67/*
68 * The RFC1051-specific components.
69 */
70struct arc_rfc1051 {
71 __u8 proto; /* ARC_P_RFC1051_ARP/RFC1051_IP */
72 __u8 payload[]; /* 507 bytes */
73};
74#define RFC1051_HDR_SIZE 1
75
76/*
77 * The ethernet-encap-specific components. We have a real ethernet header
78 * and some data.
79 */
80struct arc_eth_encap {
81 __u8 proto; /* Always ARC_P_ETHER */
82 struct ethhdr eth; /* standard ethernet header (yuck!) */
83 __u8 payload[]; /* 493 bytes */
84};
85#define ETH_ENCAP_HDR_SIZE 14
86
87struct arc_cap {
88 __u8 proto;
89 __u8 cookie[sizeof(int)];
90 /* Actually NOT sent over the network */
91 union {
92 __u8 ack;
93 __u8 raw[0]; /* 507 bytes */
94 } mes;
95};
96
97/*
98 * The data needed by the actual arcnet hardware.
99 *
100 * Now, in the real arcnet hardware, the third and fourth bytes are the
101 * 'offset' specification instead of the length, and the soft data is at
102 * the _end_ of the 512-byte buffer. We hide this complexity inside the
103 * driver.
104 */
105struct arc_hardware {
106 __u8 source; /* source ARCnet - filled in automagically */
107 __u8 dest; /* destination ARCnet - 0 for broadcast */
108 __u8 offset[2]; /* offset bytes (some weird semantics) */
109};
110#define ARC_HDR_SIZE 4
111
112/*
113 * This is an ARCnet frame header, as seen by the kernel (and userspace,
114 * when you do a raw packet capture).
115 */
116struct archdr {
117 /* hardware requirements */
118 struct arc_hardware hard;
119
120 /* arcnet encapsulation-specific bits */
121 union {
122 struct arc_rfc1201 rfc1201;
123 struct arc_rfc1051 rfc1051;
124 struct arc_eth_encap eth_encap;
125 struct arc_cap cap;
126 __u8 raw[0]; /* 508 bytes */
127 } soft;
128};
129
130#endif /* _LINUX_IF_ARCNET_H */
131

source code of linux/include/uapi/linux/if_arcnet.h