xref: /freebsd/sys/netinet/ip.h (revision ae83180158c4c937f170e31eff311b18c0286a93)
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 /*
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  */
49 struct 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_ESO		133		/* extended security */
129 #define	IPOPT_CIPSO		134		/* commerical security */
130 #define	IPOPT_SATID		136		/* satnet id */
131 #define	IPOPT_SSRR		137		/* strict source route */
132 #define	IPOPT_RA		148		/* router alert */
133 
134 /*
135  * Offsets to fields in options other than EOL and NOP.
136  */
137 #define	IPOPT_OPTVAL		0		/* option ID */
138 #define	IPOPT_OLEN		1		/* option length */
139 #define IPOPT_OFFSET		2		/* offset within option */
140 #define	IPOPT_MINOFF		4		/* min value of above */
141 
142 /*
143  * Time stamp option structure.
144  */
145 struct	ip_timestamp {
146 	u_char	ipt_code;		/* IPOPT_TS */
147 	u_char	ipt_len;		/* size of structure (variable) */
148 	u_char	ipt_ptr;		/* index of current entry */
149 #if BYTE_ORDER == LITTLE_ENDIAN
150 	u_int	ipt_flg:4,		/* flags, see below */
151 		ipt_oflw:4;		/* overflow counter */
152 #endif
153 #if BYTE_ORDER == BIG_ENDIAN
154 	u_int	ipt_oflw:4,		/* overflow counter */
155 		ipt_flg:4;		/* flags, see below */
156 #endif
157 	union ipt_timestamp {
158 		n_long	ipt_time[1];
159 		struct	ipt_ta {
160 			struct in_addr ipt_addr;
161 			n_long ipt_time;
162 		} ipt_ta[1];
163 	} ipt_timestamp;
164 };
165 
166 /* flag bits for ipt_flg */
167 #define	IPOPT_TS_TSONLY		0		/* timestamps only */
168 #define	IPOPT_TS_TSANDADDR	1		/* timestamps and addresses */
169 #define	IPOPT_TS_PRESPEC	3		/* specified modules only */
170 
171 /* bits for security (not byte swapped) */
172 #define	IPOPT_SECUR_UNCLASS	0x0000
173 #define	IPOPT_SECUR_CONFID	0xf135
174 #define	IPOPT_SECUR_EFTO	0x789a
175 #define	IPOPT_SECUR_MMMM	0xbc4d
176 #define	IPOPT_SECUR_RESTR	0xaf13
177 #define	IPOPT_SECUR_SECRET	0xd788
178 #define	IPOPT_SECUR_TOPSECRET	0x6bc5
179 
180 /*
181  * Internet implementation parameters.
182  */
183 #define	MAXTTL		255		/* maximum time to live (seconds) */
184 #define	IPDEFTTL	64		/* default ttl, from RFC 1340 */
185 #define	IPFRAGTTL	60		/* time to live for frags, slowhz */
186 #define	IPTTLDEC	1		/* subtracted when forwarding */
187 
188 #define	IP_MSS		576		/* default maximum segment size */
189 
190 #endif
191