ip.h revision 8876
1/*
2 * Copyright (c) 1982, 1986, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 *	@(#)ip.h	8.1 (Berkeley) 6/10/93
34 * $Id: ip.h,v 1.4 1995/05/05 14:36:38 ache Exp $
35 */
36
37#ifndef _NETINET_IP_H_
38#define _NETINET_IP_H_
39
40/*
41 * Definitions for internet protocol version 4.
42 * Per RFC 791, September 1981.
43 */
44#define	IPVERSION	4
45
46/*
47 * Structure of an internet header, naked of options.
48 *
49 * We declare ip_len and ip_off to be short, rather than u_short
50 * pragmatically since otherwise unsigned comparisons can result
51 * against negative integers quite easily, and fail in subtle ways.
52 */
53struct ip {
54#if BYTE_ORDER == LITTLE_ENDIAN
55	u_char	ip_hl:4,		/* header length */
56		ip_v:4;			/* version */
57#endif
58#if BYTE_ORDER == BIG_ENDIAN
59	u_char	ip_v:4,			/* version */
60		ip_hl:4;		/* header length */
61#endif
62	u_char	ip_tos;			/* type of service */
63	short	ip_len;			/* total length */
64	u_short	ip_id;			/* identification */
65	short	ip_off;			/* fragment offset field */
66#define	IP_DF 0x4000			/* dont fragment flag */
67#define	IP_MF 0x2000			/* more fragments flag */
68#define	IP_OFFMASK 0x1fff		/* mask for fragmenting bits */
69	u_char	ip_ttl;			/* time to live */
70	u_char	ip_p;			/* protocol */
71	u_short	ip_sum;			/* checksum */
72	struct	in_addr ip_src,ip_dst;	/* source and dest address */
73};
74
75#define	IP_MAXPACKET	65535		/* maximum packet size */
76
77/*
78 * Definitions for IP type of service (ip_tos)
79 */
80#define	IPTOS_LOWDELAY		0x10
81#define	IPTOS_THROUGHPUT	0x08
82#define	IPTOS_RELIABILITY	0x04
83#define	IPTOS_MINCOST		0x02
84
85/*
86 * Definitions for IP precedence (also in ip_tos) (hopefully unused)
87 */
88#define	IPTOS_PREC_NETCONTROL		0xe0
89#define	IPTOS_PREC_INTERNETCONTROL	0xc0
90#define	IPTOS_PREC_CRITIC_ECP		0xa0
91#define	IPTOS_PREC_FLASHOVERRIDE	0x80
92#define	IPTOS_PREC_FLASH		0x60
93#define	IPTOS_PREC_IMMEDIATE		0x40
94#define	IPTOS_PREC_PRIORITY		0x20
95#define	IPTOS_PREC_ROUTINE		0x00
96
97/*
98 * Definitions for options.
99 */
100#define	IPOPT_COPIED(o)		((o)&0x80)
101#define	IPOPT_CLASS(o)		((o)&0x60)
102#define	IPOPT_NUMBER(o)		((o)&0x1f)
103
104#define	IPOPT_CONTROL		0x00
105#define	IPOPT_RESERVED1		0x20
106#define	IPOPT_DEBMEAS		0x40
107#define	IPOPT_RESERVED2		0x60
108
109#define	IPOPT_EOL		0		/* end of option list */
110#define	IPOPT_NOP		1		/* no operation */
111
112#define	IPOPT_RR		7		/* record packet route */
113#define	IPOPT_TS		68		/* timestamp */
114#define	IPOPT_SECURITY		130		/* provide s,c,h,tcc */
115#define	IPOPT_LSRR		131		/* loose source route */
116#define	IPOPT_SATID		136		/* satnet id */
117#define	IPOPT_SSRR		137		/* strict source route */
118
119/*
120 * Offsets to fields in options other than EOL and NOP.
121 */
122#define	IPOPT_OPTVAL		0		/* option ID */
123#define	IPOPT_OLEN		1		/* option length */
124#define IPOPT_OFFSET		2		/* offset within option */
125#define	IPOPT_MINOFF		4		/* min value of above */
126
127/*
128 * Time stamp option structure.
129 */
130struct	ip_timestamp {
131	u_char	ipt_code;		/* IPOPT_TS */
132	u_char	ipt_len;		/* size of structure (variable) */
133	u_char	ipt_ptr;		/* index of current entry */
134#if BYTE_ORDER == LITTLE_ENDIAN
135	u_char	ipt_flg:4,		/* flags, see below */
136		ipt_oflw:4;		/* overflow counter */
137#endif
138#if BYTE_ORDER == BIG_ENDIAN
139	u_char	ipt_oflw:4,		/* overflow counter */
140		ipt_flg:4;		/* flags, see below */
141#endif
142	union ipt_timestamp {
143		n_long	ipt_time[1];
144		struct	ipt_ta {
145			struct in_addr ipt_addr;
146			n_long ipt_time;
147		} ipt_ta[1];
148	} ipt_timestamp;
149};
150
151/* flag bits for ipt_flg */
152#define	IPOPT_TS_TSONLY		0		/* timestamps only */
153#define	IPOPT_TS_TSANDADDR	1		/* timestamps and addresses */
154#define	IPOPT_TS_PRESPEC	3		/* specified modules only */
155
156/* bits for security (not byte swapped) */
157#define	IPOPT_SECUR_UNCLASS	0x0000
158#define	IPOPT_SECUR_CONFID	0xf135
159#define	IPOPT_SECUR_EFTO	0x789a
160#define	IPOPT_SECUR_MMMM	0xbc4d
161#define	IPOPT_SECUR_RESTR	0xaf13
162#define	IPOPT_SECUR_SECRET	0xd788
163#define	IPOPT_SECUR_TOPSECRET	0x6bc5
164
165/*
166 * Internet implementation parameters.
167 */
168#define	MAXTTL		255		/* maximum time to live (seconds) */
169#define	IPDEFTTL	64		/* default ttl, from RFC 1340 */
170#define	IPFRAGTTL	60		/* time to live for frags, slowhz */
171#define	IPTTLDEC	1		/* subtracted when forwarding */
172
173#define	IP_MSS		576		/* default maximum segment size */
174
175#endif
176