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 */
35
36#ifndef netdissect_ip_h
37#define netdissect_ip_h
38
39/*
40 * Definitions for internet protocol version 4.
41 * Per RFC 791, September 1981.
42 */
43#define	IPVERSION	4
44
45/*
46 * Structure of an internet header, naked of options.
47 *
48 * We declare ip_len and ip_off to be short, rather than u_short
49 * pragmatically since otherwise unsigned comparisons can result
50 * against negative integers quite easily, and fail in subtle ways.
51 */
52struct ip {
53	nd_uint8_t	ip_vhl;		/* header length, version */
54#define IP_V(ip)	((GET_U_1((ip)->ip_vhl) & 0xf0) >> 4)
55#define IP_HL(ip)	(GET_U_1((ip)->ip_vhl) & 0x0f)
56	nd_uint8_t	ip_tos;		/* type of service */
57	nd_uint16_t	ip_len;		/* total length */
58	nd_uint16_t	ip_id;		/* identification */
59	nd_uint16_t	ip_off;		/* fragment offset field */
60#define	IP_DF 0x4000			/* don't fragment flag */
61#define	IP_MF 0x2000			/* more fragments flag */
62#define	IP_OFFMASK 0x1fff		/* mask for fragmenting bits */
63	nd_uint8_t	ip_ttl;		/* time to live */
64	nd_uint8_t	ip_p;		/* protocol */
65	nd_uint16_t	ip_sum;		/* checksum */
66	nd_ipv4		ip_src,ip_dst;	/* source and dest address */
67};
68
69#define	IP_MAXPACKET	65535		/* maximum packet size */
70
71/*
72 * Definitions for IP type of service (ip_tos)
73 */
74#define	IPTOS_LOWDELAY		0x10
75#define	IPTOS_THROUGHPUT	0x08
76#define	IPTOS_RELIABILITY	0x04
77
78/*
79 * Definitions for IP precedence (also in ip_tos) (hopefully unused)
80 */
81#define	IPTOS_PREC_NETCONTROL		0xe0
82#define	IPTOS_PREC_INTERNETCONTROL	0xc0
83#define	IPTOS_PREC_CRITIC_ECP		0xa0
84#define	IPTOS_PREC_FLASHOVERRIDE	0x80
85#define	IPTOS_PREC_FLASH		0x60
86#define	IPTOS_PREC_IMMEDIATE		0x40
87#define	IPTOS_PREC_PRIORITY		0x20
88#define	IPTOS_PREC_ROUTINE		0x00
89
90/*
91 * Definitions for options.
92 */
93#define	IPOPT_COPIED(o)		((o)&0x80)
94#define	IPOPT_CLASS(o)		((o)&0x60)
95#define	IPOPT_NUMBER(o)		((o)&0x1f)
96
97#define	IPOPT_CONTROL		0x00
98#define	IPOPT_RESERVED1		0x20
99#define	IPOPT_DEBMEAS		0x40
100#define	IPOPT_RESERVED2		0x60
101
102#define	IPOPT_EOL		0		/* end of option list */
103#define	IPOPT_NOP		1		/* no operation */
104
105#define	IPOPT_RR		7		/* record packet route */
106#define	IPOPT_TS		68		/* timestamp */
107#define	IPOPT_RFC1393           82              /* traceroute RFC 1393 */
108#define	IPOPT_SECURITY		130		/* provide s,c,h,tcc */
109#define	IPOPT_LSRR		131		/* loose source route */
110#define	IPOPT_SATID		136		/* satnet id */
111#define	IPOPT_SSRR		137		/* strict source route */
112#define IPOPT_RA                148             /* router-alert, rfc2113 */
113
114/*
115 * Offsets to fields in options other than EOL and NOP.
116 */
117#define	IPOPT_OPTVAL		0		/* option ID */
118#define	IPOPT_OLEN		1		/* option length */
119#define IPOPT_OFFSET		2		/* offset within option */
120#define	IPOPT_MINOFF		4		/* min value of above */
121
122/*
123 * Time stamp option structure.
124 */
125struct	ip_timestamp {
126	nd_uint8_t	ipt_code;	/* IPOPT_TS */
127	nd_uint8_t	ipt_len;	/* size of structure (variable) */
128	nd_uint8_t	ipt_ptr;	/* index of current entry */
129	nd_uint8_t	ipt_oflwflg;	/* flags, overflow counter */
130#define IPTS_OFLW(ip)	(((ipt)->ipt_oflwflg & 0xf0) >> 4)
131#define IPTS_FLG(ip)	((ipt)->ipt_oflwflg & 0x0f)
132	union ipt_timestamp {
133		nd_uint32_t ipt_time[1];
134		struct	ipt_ta {
135			nd_ipv4 ipt_addr;
136			nd_uint32_t ipt_time;
137		} ipt_ta[1];
138	} ipt_timestamp;
139};
140
141/* flag bits for ipt_flg */
142#define	IPOPT_TS_TSONLY		0		/* timestamps only */
143#define	IPOPT_TS_TSANDADDR	1		/* timestamps and addresses */
144#define	IPOPT_TS_PRESPEC	3		/* specified modules only */
145
146/* bits for security (not byte swapped) */
147#define	IPOPT_SECUR_UNCLASS	0x0000
148#define	IPOPT_SECUR_CONFID	0xf135
149#define	IPOPT_SECUR_EFTO	0x789a
150#define	IPOPT_SECUR_MMMM	0xbc4d
151#define	IPOPT_SECUR_RESTR	0xaf13
152#define	IPOPT_SECUR_SECRET	0xd788
153#define	IPOPT_SECUR_TOPSECRET	0x6bc5
154
155/*
156 * Internet implementation parameters.
157 */
158#define	MAXTTL		255		/* maximum time to live (seconds) */
159#define	IPDEFTTL	64		/* default ttl, from RFC 1340 */
160#define	IPFRAGTTL	60		/* time to live for frags, slowhz */
161#define	IPTTLDEC	1		/* subtracted when forwarding */
162
163#define	IP_MSS		576		/* default maximum segment size */
164#endif /* netdissect_ip_h */
165