1/*
2 * INET		An implementation of the TCP/IP protocol suite for the LINUX
3 *		operating system.  INET is implemented using the  BSD Socket
4 *		interface as the means of communication with the user level.
5 *
6 *		Definitions for the IP protocol.
7 *
8 * Version:	@(#)ip.h	1.0.2	04/28/93
9 *
10 * Authors:	Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
11 *
12 *		This program is free software; you can redistribute it and/or
13 *		modify it under the terms of the GNU General Public License
14 *		as published by the Free Software Foundation; either version
15 *		2 of the License, or (at your option) any later version.
16 */
17#ifndef _LINUX_IP_H
18#define _LINUX_IP_H
19#include <asm/byteorder.h>
20
21/* SOL_IP socket options */
22
23#define IPTOS_TOS_MASK		0x1E
24#define IPTOS_TOS(tos)		((tos)&IPTOS_TOS_MASK)
25#define	IPTOS_LOWDELAY		0x10
26#define	IPTOS_THROUGHPUT	0x08
27#define	IPTOS_RELIABILITY	0x04
28#define	IPTOS_MINCOST		0x02
29
30#define IPTOS_PREC_MASK		0xE0
31#define IPTOS_PREC(tos)		((tos)&IPTOS_PREC_MASK)
32#define IPTOS_PREC_NETCONTROL           0xe0
33#define IPTOS_PREC_INTERNETCONTROL      0xc0
34#define IPTOS_PREC_CRITIC_ECP           0xa0
35#define IPTOS_PREC_FLASHOVERRIDE        0x80
36#define IPTOS_PREC_FLASH                0x60
37#define IPTOS_PREC_IMMEDIATE            0x40
38#define IPTOS_PREC_PRIORITY             0x20
39#define IPTOS_PREC_ROUTINE              0x00
40
41
42/* IP options */
43#define IPOPT_COPY		0x80
44#define IPOPT_CLASS_MASK	0x60
45#define IPOPT_NUMBER_MASK	0x1f
46
47#define	IPOPT_COPIED(o)		((o)&IPOPT_COPY)
48#define	IPOPT_CLASS(o)		((o)&IPOPT_CLASS_MASK)
49#define	IPOPT_NUMBER(o)		((o)&IPOPT_NUMBER_MASK)
50
51#define	IPOPT_CONTROL		0x00
52#define	IPOPT_RESERVED1		0x20
53#define	IPOPT_MEASUREMENT	0x40
54#define	IPOPT_RESERVED2		0x60
55
56#define IPOPT_END	(0 |IPOPT_CONTROL)
57#define IPOPT_NOOP	(1 |IPOPT_CONTROL)
58#define IPOPT_SEC	(2 |IPOPT_CONTROL|IPOPT_COPY)
59#define IPOPT_LSRR	(3 |IPOPT_CONTROL|IPOPT_COPY)
60#define IPOPT_TIMESTAMP	(4 |IPOPT_MEASUREMENT)
61#define IPOPT_RR	(7 |IPOPT_CONTROL)
62#define IPOPT_SID	(8 |IPOPT_CONTROL|IPOPT_COPY)
63#define IPOPT_SSRR	(9 |IPOPT_CONTROL|IPOPT_COPY)
64#define IPOPT_RA	(20|IPOPT_CONTROL|IPOPT_COPY)
65
66#define IPVERSION	4
67#define MAXTTL		255
68#define IPDEFTTL	64
69
70/* struct timestamp, struct route and MAX_ROUTES are removed.
71
72   REASONS: it is clear that nobody used them because:
73   - MAX_ROUTES value was wrong.
74   - "struct route" was wrong.
75   - "struct timestamp" had fatally misaligned bitfields and was completely unusable.
76 */
77
78#define IPOPT_OPTVAL 0
79#define IPOPT_OLEN   1
80#define IPOPT_OFFSET 2
81#define IPOPT_MINOFF 4
82#define MAX_IPOPTLEN 40
83#define IPOPT_NOP IPOPT_NOOP
84#define IPOPT_EOL IPOPT_END
85#define IPOPT_TS  IPOPT_TIMESTAMP
86
87#define	IPOPT_TS_TSONLY		0		/* timestamps only */
88#define	IPOPT_TS_TSANDADDR	1		/* timestamps and addresses */
89#define	IPOPT_TS_PRESPEC	3		/* specified modules only */
90
91#ifdef __KERNEL__
92
93struct ip_options {
94  __u32		faddr;				/* Saved first hop address */
95  unsigned char	optlen;
96  unsigned char srr;
97  unsigned char rr;
98  unsigned char ts;
99  unsigned char is_setbyuser:1,			/* Set by setsockopt?			*/
100                is_data:1,			/* Options in __data, rather than skb	*/
101                is_strictroute:1,		/* Strict source route			*/
102                srr_is_hit:1,			/* Packet destination addr was our one	*/
103                is_changed:1,			/* IP checksum more not valid		*/
104                rr_needaddr:1,			/* Need to record addr of outgoing dev	*/
105                ts_needtime:1,			/* Need to record timestamp		*/
106                ts_needaddr:1;			/* Need to record addr of outgoing dev  */
107  unsigned char router_alert;
108  unsigned char __pad1;
109  unsigned char __pad2;
110  unsigned char __data[0];
111};
112
113#define optlength(opt) (sizeof(struct ip_options) + opt->optlen)
114#endif
115
116struct iphdr {
117#if defined(__LITTLE_ENDIAN_BITFIELD)
118	__u8	ihl:4,
119		version:4;
120#elif defined(__BIG_ENDIAN_BITFIELD)
121	__u8	version:4,
122  		ihl:4;
123#else
124#error	"Please fix <asm/byteorder.h>"
125#endif
126	__u8	tos;
127	__u16	tot_len;
128	__u16	id;
129	__u16	frag_off;
130	__u8	ttl;
131	__u8	protocol;
132	__u16	check;
133	__u32	saddr;
134	__u32	daddr;
135	/*The options start here. */
136};
137
138#endif	/* _LINUX_IP_H */
139