ip.h revision 1.1 1 /*
2 * Copyright (c) 1982, 1986 Regents of the University of California.
3 * 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 7.10 (Berkeley) 6/28/90
34 */
35
36 /*
37 * Definitions for internet protocol version 4.
38 * Per RFC 791, September 1981.
39 */
40 #define IPVERSION 4
41
42 /*
43 * Structure of an internet header, naked of options.
44 *
45 * We declare ip_len and ip_off to be short, rather than u_short
46 * pragmatically since otherwise unsigned comparisons can result
47 * against negative integers quite easily, and fail in subtle ways.
48 */
49 struct ip {
50 #if BYTE_ORDER == LITTLE_ENDIAN
51 u_char ip_hl:4, /* header length */
52 ip_v:4; /* version */
53 #endif
54 #if BYTE_ORDER == BIG_ENDIAN
55 u_char ip_v:4, /* version */
56 ip_hl:4; /* header length */
57 #endif
58 u_char ip_tos; /* type of service */
59 short ip_len; /* total length */
60 u_short ip_id; /* identification */
61 short ip_off; /* fragment offset field */
62 #define IP_DF 0x4000 /* dont fragment flag */
63 #define IP_MF 0x2000 /* more fragments flag */
64 u_char ip_ttl; /* time to live */
65 u_char ip_p; /* protocol */
66 u_short 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
79 /*
80 * Definitions for IP precedence (also in ip_tos) (hopefully unused)
81 */
82 #define IPTOS_PREC_NETCONTROL 0xe0
83 #define IPTOS_PREC_INTERNETCONTROL 0xc0
84 #define IPTOS_PREC_CRITIC_ECP 0xa0
85 #define IPTOS_PREC_FLASHOVERRIDE 0x80
86 #define IPTOS_PREC_FLASH 0x60
87 #define IPTOS_PREC_IMMEDIATE 0x40
88 #define IPTOS_PREC_PRIORITY 0x20
89 #define IPTOS_PREC_ROUTINE 0x10
90
91 /*
92 * Definitions for options.
93 */
94 #define IPOPT_COPIED(o) ((o)&0x80)
95 #define IPOPT_CLASS(o) ((o)&0x60)
96 #define IPOPT_NUMBER(o) ((o)&0x1f)
97
98 #define IPOPT_CONTROL 0x00
99 #define IPOPT_RESERVED1 0x20
100 #define IPOPT_DEBMEAS 0x40
101 #define IPOPT_RESERVED2 0x60
102
103 #define IPOPT_EOL 0 /* end of option list */
104 #define IPOPT_NOP 1 /* no operation */
105
106 #define IPOPT_RR 7 /* record packet route */
107 #define IPOPT_TS 68 /* timestamp */
108 #define IPOPT_SECURITY 130 /* provide s,c,h,tcc */
109 #define IPOPT_LSRR 131 /* loose source route */
110 #define IPOPT_SATID 136 /* satnet id */
111 #define IPOPT_SSRR 137 /* strict source route */
112
113 /*
114 * Offsets to fields in options other than EOL and NOP.
115 */
116 #define IPOPT_OPTVAL 0 /* option ID */
117 #define IPOPT_OLEN 1 /* option length */
118 #define IPOPT_OFFSET 2 /* offset within option */
119 #define IPOPT_MINOFF 4 /* min value of above */
120
121 /*
122 * Time stamp option structure.
123 */
124 struct ip_timestamp {
125 u_char ipt_code; /* IPOPT_TS */
126 u_char ipt_len; /* size of structure (variable) */
127 u_char ipt_ptr; /* index of current entry */
128 #if BYTE_ORDER == LITTLE_ENDIAN
129 u_char ipt_flg:4, /* flags, see below */
130 ipt_oflw:4; /* overflow counter */
131 #endif
132 #if BYTE_ORDER == BIG_ENDIAN
133 u_char ipt_oflw:4, /* overflow counter */
134 ipt_flg:4; /* flags, see below */
135 #endif
136 union ipt_timestamp {
137 n_long ipt_time[1];
138 struct ipt_ta {
139 struct in_addr ipt_addr;
140 n_long ipt_time;
141 } ipt_ta[1];
142 } ipt_timestamp;
143 };
144
145 /* flag bits for ipt_flg */
146 #define IPOPT_TS_TSONLY 0 /* timestamps only */
147 #define IPOPT_TS_TSANDADDR 1 /* timestamps and addresses */
148 #define IPOPT_TS_PRESPEC 3 /* specified modules only */
149
150 /* bits for security (not byte swapped) */
151 #define IPOPT_SECUR_UNCLASS 0x0000
152 #define IPOPT_SECUR_CONFID 0xf135
153 #define IPOPT_SECUR_EFTO 0x789a
154 #define IPOPT_SECUR_MMMM 0xbc4d
155 #define IPOPT_SECUR_RESTR 0xaf13
156 #define IPOPT_SECUR_SECRET 0xd788
157 #define IPOPT_SECUR_TOPSECRET 0x6bc5
158
159 /*
160 * Internet implementation parameters.
161 */
162 #define MAXTTL 255 /* maximum time to live (seconds) */
163 #define IPFRAGTTL 60 /* time to live for frags, slowhz */
164 #define IPTTLDEC 1 /* subtracted when forwarding */
165
166 #define IP_MSS 576 /* default maximum segment size */
167