xref: /netbsd-src/sys/netinet/ip.h (revision 220b5c059a84c51ea44107ea8951a57ffaecdc8c)
1 /*	$NetBSD: ip.h,v 1.22 2001/10/24 05:56:49 itojun Exp $	*/
2 
3 /*
4  * Copyright (c) 1982, 1986, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	@(#)ip.h	8.2 (Berkeley) 6/1/94
36  */
37 
38 #ifndef _NETINET_IP_H_
39 #define _NETINET_IP_H_
40 
41 /*
42  * Definitions for internet protocol version 4.
43  * Per RFC 791, September 1981.
44  */
45 #define	IPVERSION	4
46 
47 /*
48  * Structure of an internet header, naked of options.
49  */
50 struct ip {
51 #if BYTE_ORDER == LITTLE_ENDIAN
52 	u_int8_t  ip_hl:4,		/* header length */
53 		  ip_v:4;		/* version */
54 #endif
55 #if BYTE_ORDER == BIG_ENDIAN
56 	u_int8_t  ip_v:4,		/* version */
57 		  ip_hl:4;		/* header length */
58 #endif
59 	u_int8_t  ip_tos;		/* type of service */
60 	u_int16_t ip_len;		/* total length */
61 	u_int16_t ip_id;		/* identification */
62 	u_int16_t ip_off;		/* fragment offset field */
63 #define	IP_RF 0x8000			/* reserved fragment flag */
64 #define	IP_DF 0x4000			/* dont fragment flag */
65 #define	IP_MF 0x2000			/* more fragments flag */
66 #define	IP_OFFMASK 0x1fff		/* mask for fragmenting bits */
67 	u_int8_t  ip_ttl;		/* time to live */
68 	u_int8_t  ip_p;			/* protocol */
69 	u_int16_t ip_sum;		/* checksum */
70 	struct	  in_addr ip_src, ip_dst; /* source and dest address */
71 } __attribute__((__packed__));
72 
73 #define	IP_MAXPACKET	65535		/* maximum packet size */
74 
75 /*
76  * Definitions for IP type of service (ip_tos)
77  */
78 #define	IPTOS_LOWDELAY		0x10
79 #define	IPTOS_THROUGHPUT	0x08
80 #define	IPTOS_RELIABILITY	0x04
81 /*	IPTOS_LOWCOST		0x02 XXX */
82 #if 1
83 /* ECN bits proposed by Sally Floyd */
84 #define IPTOS_CE		0x01	/* congestion experienced */
85 #define IPTOS_ECT		0x02	/* ECN-capable transport */
86 #endif
87 
88 /*
89  * Definitions for IP precedence (also in ip_tos) (hopefully unused)
90  */
91 #define	IPTOS_PREC_NETCONTROL		0xe0
92 #define	IPTOS_PREC_INTERNETCONTROL	0xc0
93 #define	IPTOS_PREC_CRITIC_ECP		0xa0
94 #define	IPTOS_PREC_FLASHOVERRIDE	0x80
95 #define	IPTOS_PREC_FLASH		0x60
96 #define	IPTOS_PREC_IMMEDIATE		0x40
97 #define	IPTOS_PREC_PRIORITY		0x20
98 #define	IPTOS_PREC_ROUTINE		0x00
99 
100 /*
101  * Definitions for options.
102  */
103 #define	IPOPT_COPIED(o)		((o)&0x80)
104 #define	IPOPT_CLASS(o)		((o)&0x60)
105 #define	IPOPT_NUMBER(o)		((o)&0x1f)
106 
107 #define	IPOPT_CONTROL		0x00
108 #define	IPOPT_RESERVED1		0x20
109 #define	IPOPT_DEBMEAS		0x40
110 #define	IPOPT_RESERVED2		0x60
111 
112 #define	IPOPT_EOL		0		/* end of option list */
113 #define	IPOPT_NOP		1		/* no operation */
114 
115 #define	IPOPT_RR		7		/* record packet route */
116 #define	IPOPT_TS		68		/* timestamp */
117 #define	IPOPT_SECURITY		130		/* provide s,c,h,tcc */
118 #define	IPOPT_LSRR		131		/* loose source route */
119 #define	IPOPT_SATID		136		/* satnet id */
120 #define	IPOPT_SSRR		137		/* strict source route */
121 
122 /*
123  * Offsets to fields in options other than EOL and NOP.
124  */
125 #define	IPOPT_OPTVAL		0		/* option ID */
126 #define	IPOPT_OLEN		1		/* option length */
127 #define	IPOPT_OFFSET		2		/* offset within option */
128 #define	IPOPT_MINOFF		4		/* min value of above */
129 
130 /*
131  * Time stamp option structure.
132  */
133 struct	ip_timestamp {
134 	u_int8_t ipt_code;		/* IPOPT_TS */
135 	u_int8_t ipt_len;		/* size of structure (variable) */
136 	u_int8_t ipt_ptr;		/* index of current entry */
137 #if BYTE_ORDER == LITTLE_ENDIAN
138 	u_int8_t ipt_flg:4,		/* flags, see below */
139 		 ipt_oflw:4;		/* overflow counter */
140 #endif
141 #if BYTE_ORDER == BIG_ENDIAN
142 	u_int8_t ipt_oflw:4,		/* overflow counter */
143 		 ipt_flg:4;		/* flags, see below */
144 #endif
145 	union ipt_timestamp {
146 		 n_time	ipt_time[1];
147 		 struct	ipt_ta {
148 			struct in_addr ipt_addr;
149 			n_time ipt_time;
150 		 } ipt_ta[1] __attribute__((__packed__));
151 	} ipt_timestamp __attribute__((__packed__));
152 } __attribute__((__packed__));
153 
154 /* flag bits for ipt_flg */
155 #define	IPOPT_TS_TSONLY		0		/* timestamps only */
156 #define	IPOPT_TS_TSANDADDR	1		/* timestamps and addresses */
157 #define	IPOPT_TS_PRESPEC	3		/* specified modules only */
158 
159 /* bits for security (not byte swapped) */
160 #define	IPOPT_SECUR_UNCLASS	0x0000
161 #define	IPOPT_SECUR_CONFID	0xf135
162 #define	IPOPT_SECUR_EFTO	0x789a
163 #define	IPOPT_SECUR_MMMM	0xbc4d
164 #define	IPOPT_SECUR_RESTR	0xaf13
165 #define	IPOPT_SECUR_SECRET	0xd788
166 #define	IPOPT_SECUR_TOPSECRET	0x6bc5
167 
168 /*
169  * Internet implementation parameters.
170  */
171 #define	MAXTTL		255		/* maximum time to live (seconds) */
172 #define	IPDEFTTL	64		/* default ttl, from RFC 1340 */
173 #define	IPFRAGTTL	60		/* time to live for frags, slowhz */
174 #define	IPTTLDEC	1		/* subtracted when forwarding */
175 
176 #define	IP_MSS		576		/* default maximum segment size */
177 
178 #endif /* _NETINET_IP_H_ */
179