xref: /freebsd/sys/netinet/ip.h (revision 729362425c09cf6b362366aabc6fb547eee8035a)
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  * $FreeBSD$
35  */
36 
37 #ifndef _NETINET_IP_H_
38 #define _NETINET_IP_H_
39 
40 #include <sys/cdefs.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_int	ip_hl:4,		/* header length */
54 		ip_v:4;			/* version */
55 #endif
56 #if BYTE_ORDER == BIG_ENDIAN
57 	u_int	ip_v:4,			/* version */
58 		ip_hl:4;		/* header length */
59 #endif
60 	u_char	ip_tos;			/* type of service */
61 	u_short	ip_len;			/* total length */
62 	u_short	ip_id;			/* identification */
63 	u_short	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_char	ip_ttl;			/* time to live */
69 	u_char	ip_p;			/* protocol */
70 	u_short	ip_sum;			/* checksum */
71 	struct	in_addr ip_src,ip_dst;	/* source and dest address */
72 } __packed;
73 
74 #ifdef CTASSERT
75 CTASSERT(sizeof (struct ip) == 20);
76 #endif
77 
78 #define	IP_MAXPACKET	65535		/* maximum packet size */
79 
80 /*
81  * Definitions for IP type of service (ip_tos)
82  */
83 #define	IPTOS_LOWDELAY		0x10
84 #define	IPTOS_THROUGHPUT	0x08
85 #define	IPTOS_RELIABILITY	0x04
86 #define	IPTOS_MINCOST		0x02
87 /* ECN bits proposed by Sally Floyd */
88 #define	IPTOS_CE		0x01	/* congestion experienced */
89 #define	IPTOS_ECT		0x02	/* ECN-capable transport */
90 
91 
92 /*
93  * Definitions for IP precedence (also in ip_tos) (hopefully unused)
94  */
95 #define	IPTOS_PREC_NETCONTROL		0xe0
96 #define	IPTOS_PREC_INTERNETCONTROL	0xc0
97 #define	IPTOS_PREC_CRITIC_ECP		0xa0
98 #define	IPTOS_PREC_FLASHOVERRIDE	0x80
99 #define	IPTOS_PREC_FLASH		0x60
100 #define	IPTOS_PREC_IMMEDIATE		0x40
101 #define	IPTOS_PREC_PRIORITY		0x20
102 #define	IPTOS_PREC_ROUTINE		0x00
103 
104 /*
105  * Definitions for options.
106  */
107 #define	IPOPT_COPIED(o)		((o)&0x80)
108 #define	IPOPT_CLASS(o)		((o)&0x60)
109 #define	IPOPT_NUMBER(o)		((o)&0x1f)
110 
111 #define	IPOPT_CONTROL		0x00
112 #define	IPOPT_RESERVED1		0x20
113 #define	IPOPT_DEBMEAS		0x40
114 #define	IPOPT_RESERVED2		0x60
115 
116 #define	IPOPT_EOL		0		/* end of option list */
117 #define	IPOPT_NOP		1		/* no operation */
118 
119 #define	IPOPT_RR		7		/* record packet route */
120 #define	IPOPT_TS		68		/* timestamp */
121 #define	IPOPT_SECURITY		130		/* provide s,c,h,tcc */
122 #define	IPOPT_LSRR		131		/* loose source route */
123 #define	IPOPT_ESO		133		/* extended security */
124 #define	IPOPT_CIPSO		134		/* commerical security */
125 #define	IPOPT_SATID		136		/* satnet id */
126 #define	IPOPT_SSRR		137		/* strict source route */
127 #define	IPOPT_RA		148		/* router alert */
128 
129 /*
130  * Offsets to fields in options other than EOL and NOP.
131  */
132 #define	IPOPT_OPTVAL		0		/* option ID */
133 #define	IPOPT_OLEN		1		/* option length */
134 #define IPOPT_OFFSET		2		/* offset within option */
135 #define	IPOPT_MINOFF		4		/* min value of above */
136 
137 /*
138  * Time stamp option structure.
139  */
140 struct	ip_timestamp {
141 	u_char	ipt_code;		/* IPOPT_TS */
142 	u_char	ipt_len;		/* size of structure (variable) */
143 	u_char	ipt_ptr;		/* index of current entry */
144 #if BYTE_ORDER == LITTLE_ENDIAN
145 	u_int	ipt_flg:4,		/* flags, see below */
146 		ipt_oflw:4;		/* overflow counter */
147 #endif
148 #if BYTE_ORDER == BIG_ENDIAN
149 	u_int	ipt_oflw:4,		/* overflow counter */
150 		ipt_flg:4;		/* flags, see below */
151 #endif
152 	union ipt_timestamp {
153 		n_long	ipt_time[1];
154 		struct	ipt_ta {
155 			struct in_addr ipt_addr;
156 			n_long ipt_time;
157 		} ipt_ta[1];
158 	} ipt_timestamp;
159 };
160 
161 /* flag bits for ipt_flg */
162 #define	IPOPT_TS_TSONLY		0		/* timestamps only */
163 #define	IPOPT_TS_TSANDADDR	1		/* timestamps and addresses */
164 #define	IPOPT_TS_PRESPEC	3		/* specified modules only */
165 
166 /* bits for security (not byte swapped) */
167 #define	IPOPT_SECUR_UNCLASS	0x0000
168 #define	IPOPT_SECUR_CONFID	0xf135
169 #define	IPOPT_SECUR_EFTO	0x789a
170 #define	IPOPT_SECUR_MMMM	0xbc4d
171 #define	IPOPT_SECUR_RESTR	0xaf13
172 #define	IPOPT_SECUR_SECRET	0xd788
173 #define	IPOPT_SECUR_TOPSECRET	0x6bc5
174 
175 /*
176  * Internet implementation parameters.
177  */
178 #define	MAXTTL		255		/* maximum time to live (seconds) */
179 #define	IPDEFTTL	64		/* default ttl, from RFC 1340 */
180 #define	IPFRAGTTL	60		/* time to live for frags, slowhz */
181 #define	IPTTLDEC	1		/* subtracted when forwarding */
182 
183 #define	IP_MSS		576		/* default maximum segment size */
184 
185 #endif
186