ip.h revision 1.16 1 /* $NetBSD: ip.h,v 1.16 1996/12/11 01:55:50 mycroft 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 8.1 (Berkeley) 6/10/93
36 */
37
38 /*
39 * Definitions for internet protocol version 4.
40 * Per RFC 791, September 1981.
41 */
42 #define IPVERSION 4
43
44 /*
45 * Structure of an internet header, naked of options.
46 */
47 struct ip {
48 #if BYTE_ORDER == LITTLE_ENDIAN
49 u_int8_t ip_hl:4, /* header length */
50 ip_v:4; /* version */
51 #endif
52 #if BYTE_ORDER == BIG_ENDIAN
53 u_int8_t ip_v:4, /* version */
54 ip_hl:4; /* header length */
55 #endif
56 u_int8_t ip_tos; /* type of service */
57 u_int16_t ip_len; /* total length */
58 u_int16_t ip_id; /* identification */
59 u_int16_t ip_off; /* fragment offset field */
60 #define IP_RF 0x8000 /* reserved fragment flag */
61 #define IP_DF 0x4000 /* dont fragment flag */
62 #define IP_MF 0x2000 /* more fragments flag */
63 #define IP_OFFMASK 0x1fff /* mask for fragmenting bits */
64 u_int8_t ip_ttl; /* time to live */
65 u_int8_t ip_p; /* protocol */
66 u_int16_t ip_sum; /* checksum */
67 struct in_addr ip_src, ip_dst; /* source and dest address */
68 };
69
70 #define IP_MAXPACKET 65535 /* maximum packet size */
71
72 /*
73 * Definitions for IP type of service (ip_tos)
74 */
75 #define IPTOS_LOWDELAY 0x10
76 #define IPTOS_THROUGHPUT 0x08
77 #define IPTOS_RELIABILITY 0x04
78 /* IPTOS_LOWCOST 0x02 XXX */
79
80 /*
81 * Definitions for IP precedence (also in ip_tos) (hopefully unused)
82 */
83 #define IPTOS_PREC_NETCONTROL 0xe0
84 #define IPTOS_PREC_INTERNETCONTROL 0xc0
85 #define IPTOS_PREC_CRITIC_ECP 0xa0
86 #define IPTOS_PREC_FLASHOVERRIDE 0x80
87 #define IPTOS_PREC_FLASH 0x60
88 #define IPTOS_PREC_IMMEDIATE 0x40
89 #define IPTOS_PREC_PRIORITY 0x20
90 #define IPTOS_PREC_ROUTINE 0x00
91
92 /*
93 * Definitions for options.
94 */
95 #define IPOPT_COPIED(o) ((o)&0x80)
96 #define IPOPT_CLASS(o) ((o)&0x60)
97 #define IPOPT_NUMBER(o) ((o)&0x1f)
98
99 #define IPOPT_CONTROL 0x00
100 #define IPOPT_RESERVED1 0x20
101 #define IPOPT_DEBMEAS 0x40
102 #define IPOPT_RESERVED2 0x60
103
104 #define IPOPT_EOL 0 /* end of option list */
105 #define IPOPT_NOP 1 /* no operation */
106
107 #define IPOPT_RR 7 /* record packet route */
108 #define IPOPT_TS 68 /* timestamp */
109 #define IPOPT_SECURITY 130 /* provide s,c,h,tcc */
110 #define IPOPT_LSRR 131 /* loose source route */
111 #define IPOPT_SATID 136 /* satnet id */
112 #define IPOPT_SSRR 137 /* strict source route */
113
114 /*
115 * Offsets to fields in options other than EOL and NOP.
116 */
117 #define IPOPT_OPTVAL 0 /* option ID */
118 #define IPOPT_OLEN 1 /* option length */
119 #define IPOPT_OFFSET 2 /* offset within option */
120 #define IPOPT_MINOFF 4 /* min value of above */
121
122 /*
123 * Time stamp option structure.
124 */
125 struct ip_timestamp {
126 u_int8_t ipt_code; /* IPOPT_TS */
127 u_int8_t ipt_len; /* size of structure (variable) */
128 u_int8_t ipt_ptr; /* index of current entry */
129 #if BYTE_ORDER == LITTLE_ENDIAN
130 u_int8_t ipt_flg:4, /* flags, see below */
131 ipt_oflw:4; /* overflow counter */
132 #endif
133 #if BYTE_ORDER == BIG_ENDIAN
134 u_int8_t ipt_oflw:4, /* overflow counter */
135 ipt_flg:4; /* flags, see below */
136 #endif
137 union ipt_timestamp {
138 n_time ipt_time[1];
139 struct ipt_ta {
140 struct in_addr ipt_addr;
141 n_time ipt_time;
142 } ipt_ta[1];
143 } ipt_timestamp;
144 };
145
146 /* flag bits for ipt_flg */
147 #define IPOPT_TS_TSONLY 0 /* timestamps only */
148 #define IPOPT_TS_TSANDADDR 1 /* timestamps and addresses */
149 #define IPOPT_TS_PRESPEC 3 /* specified modules only */
150
151 /* bits for security (not byte swapped) */
152 #define IPOPT_SECUR_UNCLASS 0x0000
153 #define IPOPT_SECUR_CONFID 0xf135
154 #define IPOPT_SECUR_EFTO 0x789a
155 #define IPOPT_SECUR_MMMM 0xbc4d
156 #define IPOPT_SECUR_RESTR 0xaf13
157 #define IPOPT_SECUR_SECRET 0xd788
158 #define IPOPT_SECUR_TOPSECRET 0x6bc5
159
160 /*
161 * Internet implementation parameters.
162 */
163 #define MAXTTL 255 /* maximum time to live (seconds) */
164 #define IPDEFTTL 64 /* default ttl, from RFC 1340 */
165 #define IPFRAGTTL 60 /* time to live for frags, slowhz */
166 #define IPTTLDEC 1 /* subtracted when forwarding */
167
168 #define IP_MSS 576 /* default maximum segment size */
169