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  */
59 struct 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  */
70 struct 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  */
80 struct 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 
87 struct 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  */
105 struct 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  */
116 struct 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