ip.h revision 105586
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	8.2 (Berkeley) 6/1/94
34 * $FreeBSD: head/sys/netinet/ip.h 105586 2002-10-20 22:52:07Z phk $
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 */
49struct ip {
50#if BYTE_ORDER == LITTLE_ENDIAN
51	u_int	ip_hl:4,		/* header length */
52		ip_v:4;			/* version */
53#endif
54#if BYTE_ORDER == BIG_ENDIAN
55	u_int	ip_v:4,			/* version */
56		ip_hl:4;		/* header length */
57#endif
58	u_char	ip_tos;			/* type of service */
59	u_short	ip_len;			/* total length */
60	u_short	ip_id;			/* identification */
61	u_short	ip_off;			/* fragment offset field */
62#define	IP_RF 0x8000			/* reserved fragment flag */
63#define	IP_DF 0x4000			/* dont fragment flag */
64#define	IP_MF 0x2000			/* more fragments flag */
65#define	IP_OFFMASK 0x1fff		/* mask for fragmenting bits */
66	u_char	ip_ttl;			/* time to live */
67	u_char	ip_p;			/* protocol */
68	u_short	ip_sum;			/* checksum */
69	struct	in_addr ip_src,ip_dst;	/* source and dest address */
70} __attribute__((__packed__));
71
72#ifdef CTASSERT
73CTASSERT(sizeof (struct ip) == 20);
74#endif
75
76#define	IP_MAXPACKET	65535		/* maximum packet size */
77
78/*
79 * Definitions for IP type of service (ip_tos)
80 */
81#define	IPTOS_LOWDELAY		0x10
82#define	IPTOS_THROUGHPUT	0x08
83#define	IPTOS_RELIABILITY	0x04
84#define	IPTOS_MINCOST		0x02
85/* ECN bits proposed by Sally Floyd */
86#define	IPTOS_CE		0x01	/* congestion experienced */
87#define	IPTOS_ECT		0x02	/* ECN-capable transport */
88
89
90/*
91 * Definitions for IP precedence (also in ip_tos) (hopefully unused)
92 */
93#define	IPTOS_PREC_NETCONTROL		0xe0
94#define	IPTOS_PREC_INTERNETCONTROL	0xc0
95#define	IPTOS_PREC_CRITIC_ECP		0xa0
96#define	IPTOS_PREC_FLASHOVERRIDE	0x80
97#define	IPTOS_PREC_FLASH		0x60
98#define	IPTOS_PREC_IMMEDIATE		0x40
99#define	IPTOS_PREC_PRIORITY		0x20
100#define	IPTOS_PREC_ROUTINE		0x00
101
102/*
103 * Definitions for options.
104 */
105#define	IPOPT_COPIED(o)		((o)&0x80)
106#define	IPOPT_CLASS(o)		((o)&0x60)
107#define	IPOPT_NUMBER(o)		((o)&0x1f)
108
109#define	IPOPT_CONTROL		0x00
110#define	IPOPT_RESERVED1		0x20
111#define	IPOPT_DEBMEAS		0x40
112#define	IPOPT_RESERVED2		0x60
113
114#define	IPOPT_EOL		0		/* end of option list */
115#define	IPOPT_NOP		1		/* no operation */
116
117#define	IPOPT_RR		7		/* record packet route */
118#define	IPOPT_TS		68		/* timestamp */
119#define	IPOPT_SECURITY		130		/* provide s,c,h,tcc */
120#define	IPOPT_LSRR		131		/* loose source route */
121#define	IPOPT_ESO		133		/* extended security */
122#define	IPOPT_CIPSO		134		/* commerical security */
123#define	IPOPT_SATID		136		/* satnet id */
124#define	IPOPT_SSRR		137		/* strict source route */
125#define	IPOPT_RA		148		/* router alert */
126
127/*
128 * Offsets to fields in options other than EOL and NOP.
129 */
130#define	IPOPT_OPTVAL		0		/* option ID */
131#define	IPOPT_OLEN		1		/* option length */
132#define IPOPT_OFFSET		2		/* offset within option */
133#define	IPOPT_MINOFF		4		/* min value of above */
134
135/*
136 * Time stamp option structure.
137 */
138struct	ip_timestamp {
139	u_char	ipt_code;		/* IPOPT_TS */
140	u_char	ipt_len;		/* size of structure (variable) */
141	u_char	ipt_ptr;		/* index of current entry */
142#if BYTE_ORDER == LITTLE_ENDIAN
143	u_int	ipt_flg:4,		/* flags, see below */
144		ipt_oflw:4;		/* overflow counter */
145#endif
146#if BYTE_ORDER == BIG_ENDIAN
147	u_int	ipt_oflw:4,		/* overflow counter */
148		ipt_flg:4;		/* flags, see below */
149#endif
150	union ipt_timestamp {
151		n_long	ipt_time[1];
152		struct	ipt_ta {
153			struct in_addr ipt_addr;
154			n_long ipt_time;
155		} ipt_ta[1];
156	} ipt_timestamp;
157};
158
159/* flag bits for ipt_flg */
160#define	IPOPT_TS_TSONLY		0		/* timestamps only */
161#define	IPOPT_TS_TSANDADDR	1		/* timestamps and addresses */
162#define	IPOPT_TS_PRESPEC	3		/* specified modules only */
163
164/* bits for security (not byte swapped) */
165#define	IPOPT_SECUR_UNCLASS	0x0000
166#define	IPOPT_SECUR_CONFID	0xf135
167#define	IPOPT_SECUR_EFTO	0x789a
168#define	IPOPT_SECUR_MMMM	0xbc4d
169#define	IPOPT_SECUR_RESTR	0xaf13
170#define	IPOPT_SECUR_SECRET	0xd788
171#define	IPOPT_SECUR_TOPSECRET	0x6bc5
172
173/*
174 * Internet implementation parameters.
175 */
176#define	MAXTTL		255		/* maximum time to live (seconds) */
177#define	IPDEFTTL	64		/* default ttl, from RFC 1340 */
178#define	IPFRAGTTL	60		/* time to live for frags, slowhz */
179#define	IPTTLDEC	1		/* subtracted when forwarding */
180
181#define	IP_MSS		576		/* default maximum segment size */
182
183#endif
184