xref: /openbsd-src/sys/netinet/ip.h (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1 /*	$OpenBSD: ip.h,v 1.7 2001/06/09 07:03:41 angelos Exp $	*/
2 /*	$NetBSD: ip.h,v 1.9 1995/05/15 01:22:44 cgd Exp $	*/
3 
4 /*
5  * Copyright (c) 1982, 1986, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)ip.h	8.1 (Berkeley) 6/10/93
37  */
38 
39 #ifndef _NETINET_IP_H_
40 #define _NETINET_IP_H_
41 
42 /*
43  * Definitions for internet protocol version 4.
44  * Per RFC 791, September 1981.
45  */
46 #define	IPVERSION	4
47 
48 /*
49  * Structure of an internet header, naked of options.
50  */
51 struct ip {
52 #if BYTE_ORDER == LITTLE_ENDIAN
53 	u_int8_t  ip_hl:4,		/* header length */
54 		  ip_v:4;		/* version */
55 #endif
56 #if BYTE_ORDER == BIG_ENDIAN
57 	u_int8_t  ip_v:4,		/* version */
58 		  ip_hl:4;		/* header length */
59 #endif
60 	u_int8_t  ip_tos;		/* type of service */
61 	u_int16_t ip_len;		/* total length */
62 	u_int16_t ip_id;		/* identification */
63 	u_int16_t ip_off;		/* fragment offset field */
64 #define	IP_RF 0x8000			/* reserved fragment flag */
65 #define	IP_DF 0x4000			/* dont fragment flag */
66 #define	IP_MF 0x2000			/* more fragments flag */
67 #define	IP_OFFMASK 0x1fff		/* mask for fragmenting bits */
68 	u_int8_t  ip_ttl;		/* time to live */
69 	u_int8_t  ip_p;			/* protocol */
70 	u_int16_t ip_sum;		/* checksum */
71 	struct	  in_addr ip_src, ip_dst; /* source and dest address */
72 };
73 
74 #define	IP_MAXPACKET	65535		/* maximum packet size */
75 
76 /*
77  * Definitions for IP type of service (ip_tos)
78  */
79 #define	IPTOS_LOWDELAY		0x10
80 #define	IPTOS_THROUGHPUT	0x08
81 #define	IPTOS_RELIABILITY	0x04
82 /*	IPTOS_LOWCOST		0x02 XXX */
83 #if 1
84 /* ECN bits proposed by Sally Floyd */
85 #define IPTOS_CE		0x01	/* congestion experienced */
86 #define IPTOS_ECT		0x02	/* ECN-capable transport */
87 #endif
88 
89 /*
90  * Definitions for IP precedence (also in ip_tos) (hopefully unused)
91  */
92 #define	IPTOS_PREC_NETCONTROL		0xe0
93 #define	IPTOS_PREC_INTERNETCONTROL	0xc0
94 #define	IPTOS_PREC_CRITIC_ECP		0xa0
95 #define	IPTOS_PREC_FLASHOVERRIDE	0x80
96 #define	IPTOS_PREC_FLASH		0x60
97 #define	IPTOS_PREC_IMMEDIATE		0x40
98 #define	IPTOS_PREC_PRIORITY		0x20
99 #define	IPTOS_PREC_ROUTINE		0x00
100 
101 /*
102  * Definitions for options.
103  */
104 #define	IPOPT_COPIED(o)		((o)&0x80)
105 #define	IPOPT_CLASS(o)		((o)&0x60)
106 #define	IPOPT_NUMBER(o)		((o)&0x1f)
107 
108 #define	IPOPT_CONTROL		0x00
109 #define	IPOPT_RESERVED1		0x20
110 #define	IPOPT_DEBMEAS		0x40
111 #define	IPOPT_RESERVED2		0x60
112 
113 #define	IPOPT_EOL		0		/* end of option list */
114 #define	IPOPT_NOP		1		/* no operation */
115 
116 #define	IPOPT_RR		7		/* record packet route */
117 #define	IPOPT_TS		68		/* timestamp */
118 #define	IPOPT_SECURITY		130		/* provide s,c,h,tcc */
119 #define	IPOPT_LSRR		131		/* loose source route */
120 #define	IPOPT_SATID		136		/* satnet id */
121 #define	IPOPT_SSRR		137		/* strict source route */
122 
123 /*
124  * Offsets to fields in options other than EOL and NOP.
125  */
126 #define	IPOPT_OPTVAL		0		/* option ID */
127 #define	IPOPT_OLEN		1		/* option length */
128 #define	IPOPT_OFFSET		2		/* offset within option */
129 #define	IPOPT_MINOFF		4		/* min value of above */
130 
131 /*
132  * Time stamp option structure.
133  */
134 struct	ip_timestamp {
135 	u_int8_t ipt_code;		/* IPOPT_TS */
136 	u_int8_t ipt_len;		/* size of structure (variable) */
137 	u_int8_t ipt_ptr;		/* index of current entry */
138 #if BYTE_ORDER == LITTLE_ENDIAN
139 	u_int8_t ipt_flg:4,		/* flags, see below */
140 		 ipt_oflw:4;		/* overflow counter */
141 #endif
142 #if BYTE_ORDER == BIG_ENDIAN
143 	u_int8_t ipt_oflw:4,		/* overflow counter */
144 		 ipt_flg:4;		/* flags, see below */
145 #endif
146 	union ipt_timestamp {
147 		 n_time	ipt_time[1];
148 		 struct	ipt_ta {
149 			struct in_addr ipt_addr;
150 			n_time ipt_time;
151 		 } ipt_ta[1];
152 	} ipt_timestamp;
153 };
154 
155 /* flag bits for ipt_flg */
156 #define	IPOPT_TS_TSONLY		0		/* timestamps only */
157 #define	IPOPT_TS_TSANDADDR	1		/* timestamps and addresses */
158 #define	IPOPT_TS_PRESPEC	3		/* specified modules only */
159 
160 /* bits for security (not byte swapped) */
161 #define	IPOPT_SECUR_UNCLASS	0x0000
162 #define	IPOPT_SECUR_CONFID	0xf135
163 #define	IPOPT_SECUR_EFTO	0x789a
164 #define	IPOPT_SECUR_MMMM	0xbc4d
165 #define	IPOPT_SECUR_RESTR	0xaf13
166 #define	IPOPT_SECUR_SECRET	0xd788
167 #define	IPOPT_SECUR_TOPSECRET	0x6bc5
168 
169 /*
170  * Internet implementation parameters.
171  */
172 #define	MAXTTL		255		/* maximum time to live (seconds) */
173 #define	IPDEFTTL	64		/* default ttl, from RFC 1340 */
174 #define	IPFRAGTTL	60		/* time to live for frags, slowhz */
175 #define	IPTTLDEC	1		/* subtracted when forwarding */
176 
177 #define	IP_MSS		576		/* default maximum segment size */
178 
179 /*
180  * This is the real IPv4 psuedo header, used for computing the TCP and UDP
181  * checksums. For the Internet checksum, struct ipovly can be used instead.
182  * For stronger checksums, the real thing must be used.
183  */
184 struct ippseudo {
185 	struct    in_addr ippseudo_src;	/* source internet address */
186 	struct    in_addr ippseudo_dst;	/* destination internet address */
187 	u_int8_t  ippseudo_pad;		/* pad, must be zero */
188 	u_int8_t  ippseudo_p;		/* protocol */
189 	u_int16_t ippseudo_len;		/* protocol length */
190 };
191 #endif /* _NETINET_IP_H_ */
192