2 * Copyright (c) 1982, 1986, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * @(#)ip.h 8.2 (Berkeley) 6/1/94
30 * $FreeBSD: src/sys/netinet/ip.h,v 1.16 1999/08/28 00:49:19 peter Exp $
33 #ifndef _NETINET_IP_H_
34 #define _NETINET_IP_H_
37 * Definitions for internet protocol version 4.
38 * Per RFC 791, September 1981.
43 * Structure of an internet header, naked of options.
47 u_char ip_vhl
; /* version << 4 | header length >> 2 */
49 #if BYTE_ORDER == LITTLE_ENDIAN
50 u_int ip_hl
:4, /* header length */
53 #if BYTE_ORDER == BIG_ENDIAN
54 u_int ip_v
:4, /* version */
55 ip_hl
:4; /* header length */
57 #endif /* not _IP_VHL */
58 u_char ip_tos
; /* type of service */
59 u_short ip_len
; /* total length */
60 u_short ip_id
; /* identification */
61 u_short ip_off
; /* fragment offset field */
62 #define IP_RF 0x8000 /* reserved fragment flag */
63 #define IP_DF 0x4000 /* dont fragment flag */
64 #define IP_MF 0x2000 /* more fragments flag */
65 #define IP_OFFMASK 0x1fff /* mask for fragmenting bits */
66 u_char ip_ttl
; /* time to live */
67 u_char ip_p
; /* protocol */
68 u_short ip_sum
; /* checksum */
69 struct in_addr ip_src
,ip_dst
; /* source and dest address */
73 #define IP_MAKE_VHL(v, hl) ((v) << 4 | (hl))
74 #define IP_VHL_HL(vhl) ((vhl) & 0x0f)
75 #define IP_VHL_V(vhl) ((vhl) >> 4)
76 #define IP_VHL_BORING 0x45
79 #define IP_MAXPACKET 65535 /* maximum packet size */
82 * Definitions for IP type of service (ip_tos)
84 #define IPTOS_LOWDELAY 0x10
85 #define IPTOS_THROUGHPUT 0x08
86 #define IPTOS_RELIABILITY 0x04
87 #define IPTOS_MINCOST 0x02
90 * Definitions for IP precedence (also in ip_tos) (hopefully unused)
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
102 * Definitions for options.
104 #define IPOPT_COPIED(o) ((o)&0x80)
105 #define IPOPT_CLASS(o) ((o)&0x60)
106 #define IPOPT_NUMBER(o) ((o)&0x1f)
108 #define IPOPT_CONTROL 0x00
109 #define IPOPT_RESERVED1 0x20
110 #define IPOPT_DEBMEAS 0x40
111 #define IPOPT_RESERVED2 0x60
113 #define IPOPT_EOL 0 /* end of option list */
114 #define IPOPT_NOP 1 /* no operation */
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 #define IPOPT_RA 148 /* router alert */
125 * Offsets to fields in options other than EOL and NOP.
127 #define IPOPT_OPTVAL 0 /* option ID */
128 #define IPOPT_OLEN 1 /* option length */
129 #define IPOPT_OFFSET 2 /* offset within option */
130 #define IPOPT_MINOFF 4 /* min value of above */
133 * Time stamp option structure.
135 struct ip_timestamp
{
136 u_char ipt_code
; /* IPOPT_TS */
137 u_char ipt_len
; /* size of structure (variable) */
138 u_char ipt_ptr
; /* index of current entry */
139 #if BYTE_ORDER == LITTLE_ENDIAN
140 u_int ipt_flg
:4, /* flags, see below */
141 ipt_oflw
:4; /* overflow counter */
143 #if BYTE_ORDER == BIG_ENDIAN
144 u_int ipt_oflw
:4, /* overflow counter */
145 ipt_flg
:4; /* flags, see below */
147 union ipt_timestamp
{
150 struct in_addr ipt_addr
;
156 /* flag bits for ipt_flg */
157 #define IPOPT_TS_TSONLY 0 /* timestamps only */
158 #define IPOPT_TS_TSANDADDR 1 /* timestamps and addresses */
159 #define IPOPT_TS_PRESPEC 3 /* specified modules only */
161 /* bits for security (not byte swapped) */
162 #define IPOPT_SECUR_UNCLASS 0x0000
163 #define IPOPT_SECUR_CONFID 0xf135
164 #define IPOPT_SECUR_EFTO 0x789a
165 #define IPOPT_SECUR_MMMM 0xbc4d
166 #define IPOPT_SECUR_RESTR 0xaf13
167 #define IPOPT_SECUR_SECRET 0xd788
168 #define IPOPT_SECUR_TOPSECRET 0x6bc5
171 * Internet implementation parameters.
173 #define MAXTTL 255 /* maximum time to live (seconds) */
174 #define IPDEFTTL 64 /* default ttl, from RFC 1340 */
175 #define IPFRAGTTL 60 /* time to live for frags, slowhz */
176 #define IPTTLDEC 1 /* subtracted when forwarding */
178 #define IP_MSS 576 /* default maximum segment size */