ip.h revision 87917
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 87917 2001-12-14 19:34:42Z rwatson $
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#ifdef _IP_VHL
51	u_char	ip_vhl;			/* version << 4 | header length >> 2 */
52#else
53#if BYTE_ORDER == LITTLE_ENDIAN
54	u_int	ip_hl:4,		/* header length */
55		ip_v:4;			/* version */
56#endif
57#if BYTE_ORDER == BIG_ENDIAN
58	u_int	ip_v:4,			/* version */
59		ip_hl:4;		/* header length */
60#endif
61#endif /* not _IP_VHL */
62	u_char	ip_tos;			/* type of service */
63	u_short	ip_len;			/* total length */
64	u_short	ip_id;			/* identification */
65	u_short	ip_off;			/* fragment offset field */
66#define	IP_RF 0x8000			/* reserved fragment flag */
67#define	IP_DF 0x4000			/* dont fragment flag */
68#define	IP_MF 0x2000			/* more fragments flag */
69#define	IP_OFFMASK 0x1fff		/* mask for fragmenting bits */
70	u_char	ip_ttl;			/* time to live */
71	u_char	ip_p;			/* protocol */
72	u_short	ip_sum;			/* checksum */
73	struct	in_addr ip_src,ip_dst;	/* source and dest address */
74};
75
76#ifdef _IP_VHL
77#define	IP_MAKE_VHL(v, hl)	((v) << 4 | (hl))
78#define	IP_VHL_HL(vhl)		((vhl) & 0x0f)
79#define	IP_VHL_V(vhl)		((vhl) >> 4)
80#define	IP_VHL_BORING		0x45
81#endif
82
83#define	IP_MAXPACKET	65535		/* maximum packet size */
84
85/*
86 * Definitions for IP type of service (ip_tos)
87 */
88#define	IPTOS_LOWDELAY		0x10
89#define	IPTOS_THROUGHPUT	0x08
90#define	IPTOS_RELIABILITY	0x04
91#define	IPTOS_MINCOST		0x02
92/* ECN bits proposed by Sally Floyd */
93#define	IPTOS_CE		0x01	/* congestion experienced */
94#define	IPTOS_ECT		0x02	/* ECN-capable transport */
95
96
97/*
98 * Definitions for IP precedence (also in ip_tos) (hopefully unused)
99 */
100#define	IPTOS_PREC_NETCONTROL		0xe0
101#define	IPTOS_PREC_INTERNETCONTROL	0xc0
102#define	IPTOS_PREC_CRITIC_ECP		0xa0
103#define	IPTOS_PREC_FLASHOVERRIDE	0x80
104#define	IPTOS_PREC_FLASH		0x60
105#define	IPTOS_PREC_IMMEDIATE		0x40
106#define	IPTOS_PREC_PRIORITY		0x20
107#define	IPTOS_PREC_ROUTINE		0x00
108
109/*
110 * Definitions for options.
111 */
112#define	IPOPT_COPIED(o)		((o)&0x80)
113#define	IPOPT_CLASS(o)		((o)&0x60)
114#define	IPOPT_NUMBER(o)		((o)&0x1f)
115
116#define	IPOPT_CONTROL		0x00
117#define	IPOPT_RESERVED1		0x20
118#define	IPOPT_DEBMEAS		0x40
119#define	IPOPT_RESERVED2		0x60
120
121#define	IPOPT_EOL		0		/* end of option list */
122#define	IPOPT_NOP		1		/* no operation */
123
124#define	IPOPT_RR		7		/* record packet route */
125#define	IPOPT_TS		68		/* timestamp */
126#define	IPOPT_SECURITY		130		/* provide s,c,h,tcc */
127#define	IPOPT_LSRR		131		/* loose source route */
128#define	IPOPT_CIPSO		134		/* commerical security */
129#define	IPOPT_SATID		136		/* satnet id */
130#define	IPOPT_SSRR		137		/* strict source route */
131#define	IPOPT_RA		148		/* router alert */
132
133/*
134 * Offsets to fields in options other than EOL and NOP.
135 */
136#define	IPOPT_OPTVAL		0		/* option ID */
137#define	IPOPT_OLEN		1		/* option length */
138#define IPOPT_OFFSET		2		/* offset within option */
139#define	IPOPT_MINOFF		4		/* min value of above */
140
141/*
142 * Time stamp option structure.
143 */
144struct	ip_timestamp {
145	u_char	ipt_code;		/* IPOPT_TS */
146	u_char	ipt_len;		/* size of structure (variable) */
147	u_char	ipt_ptr;		/* index of current entry */
148#if BYTE_ORDER == LITTLE_ENDIAN
149	u_int	ipt_flg:4,		/* flags, see below */
150		ipt_oflw:4;		/* overflow counter */
151#endif
152#if BYTE_ORDER == BIG_ENDIAN
153	u_int	ipt_oflw:4,		/* overflow counter */
154		ipt_flg:4;		/* flags, see below */
155#endif
156	union ipt_timestamp {
157		n_long	ipt_time[1];
158		struct	ipt_ta {
159			struct in_addr ipt_addr;
160			n_long ipt_time;
161		} ipt_ta[1];
162	} ipt_timestamp;
163};
164
165/* flag bits for ipt_flg */
166#define	IPOPT_TS_TSONLY		0		/* timestamps only */
167#define	IPOPT_TS_TSANDADDR	1		/* timestamps and addresses */
168#define	IPOPT_TS_PRESPEC	3		/* specified modules only */
169
170/* bits for security (not byte swapped) */
171#define	IPOPT_SECUR_UNCLASS	0x0000
172#define	IPOPT_SECUR_CONFID	0xf135
173#define	IPOPT_SECUR_EFTO	0x789a
174#define	IPOPT_SECUR_MMMM	0xbc4d
175#define	IPOPT_SECUR_RESTR	0xaf13
176#define	IPOPT_SECUR_SECRET	0xd788
177#define	IPOPT_SECUR_TOPSECRET	0x6bc5
178
179/*
180 * Internet implementation parameters.
181 */
182#define	MAXTTL		255		/* maximum time to live (seconds) */
183#define	IPDEFTTL	64		/* default ttl, from RFC 1340 */
184#define	IPFRAGTTL	60		/* time to live for frags, slowhz */
185#define	IPTTLDEC	1		/* subtracted when forwarding */
186
187#define	IP_MSS		576		/* default maximum segment size */
188
189#endif
190