1/* $NetBSD: ip.h,v 1.34 2012/11/02 21:07:07 christos 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. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * @(#)ip.h 8.2 (Berkeley) 6/1/94
32 */
33
34#ifndef _NETINET_IP_H_
35#define _NETINET_IP_H_
36
37#include <netinet/in_systm.h> /* for n_time */
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 */
47struct ip {
48#if BYTE_ORDER == LITTLE_ENDIAN
49 unsigned int ip_hl:4, /* header length */
50 ip_v:4; /* version */
51#endif
52#if BYTE_ORDER == BIG_ENDIAN
53 unsigned int 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_EF 0x8000 /* evil flag, per RFC 3514 */
62#define IP_DF 0x4000 /* dont fragment flag */
63#define IP_MF 0x2000 /* more fragments flag */
64#define IP_OFFMASK 0x1fff /* mask for fragmenting bits */
65 u_int8_t ip_ttl; /* time to live */
66 u_int8_t ip_p; /* protocol */
67 u_int16_t ip_sum; /* checksum */
68 struct in_addr ip_src, ip_dst; /* source and dest address */
69} __packed;
70
71#define IP_MAXPACKET 65535 /* maximum packet size */
72#define IP_MINFRAGSIZE 69 /* minumum size that can be fraged */
73
74/*
75 * Definitions for IP type of service (ip_tos)
76 */
77
78/*
79 * Definitions for DiffServ Codepoints as per RFC2474
80 */
81#define IPTOS_DSCP_CS0 0x00
82#define IPTOS_DSCP_CS1 0x20
83#define IPTOS_DSCP_AF11 0x28
84#define IPTOS_DSCP_AF12 0x30
85#define IPTOS_DSCP_AF13 0x38
86#define IPTOS_DSCP_CS2 0x40
87#define IPTOS_DSCP_AF21 0x48
88#define IPTOS_DSCP_AF22 0x50
89#define IPTOS_DSCP_AF23 0x58
90#define IPTOS_DSCP_CS3 0x60
91#define IPTOS_DSCP_AF31 0x68
92#define IPTOS_DSCP_AF32 0x70
93#define IPTOS_DSCP_AF33 0x78
94#define IPTOS_DSCP_CS4 0x80
95#define IPTOS_DSCP_AF41 0x88
96#define IPTOS_DSCP_AF42 0x90
97#define IPTOS_DSCP_AF43 0x98
98#define IPTOS_DSCP_CS5 0xa0
99#define IPTOS_DSCP_EF 0xb8
100#define IPTOS_DSCP_CS6 0xc0
101#define IPTOS_DSCP_CS7 0xe0
102
103/*
104 * Definitions for DiffServ Class Selector Codepoints
105 */
106#define IPTOS_CLASS_CS0 0x00
107#define IPTOS_CLASS_CS1 0x20
108#define IPTOS_CLASS_CS2 0x40
109#define IPTOS_CLASS_CS3 0x60
110#define IPTOS_CLASS_CS4 0x80
111#define IPTOS_CLASS_CS5 0xa0
112#define IPTOS_CLASS_CS6 0xc0
113#define IPTOS_CLASS_CS7 0xe0
114#define IPTOS_CLASS_DEFAULT IPTOS_CLASS_CS0
115#define IPTOS_CLASS_MASK 0xe0
116#define IPTOS_CLASS(cs) ((cs) & IPTOS_CLASS_MASK)
117#define IPTOS_DSCP_MASK 0xfc
118#define IPTOS_DSCP(cp) ((cp) & IPTOS_DSCP_MASK)
119
120/*
121 * ECN (Explicit Congestion Notification) codepoints in RFC3168
122 * mapped to the lower 2 bits of the TOS field.
123 */
124#define IPTOS_ECN_NOTECT 0x00 /* not-ECT */
125#define IPTOS_ECN_ECT1 0x01 /* ECN-capable transport (1) */
126#define IPTOS_ECN_ECT0 0x02 /* ECN-capable transport (0) */
127#define IPTOS_ECN_CE 0x03 /* congestion experienced */
128#define IPTOS_ECN_MASK 0x03 /* ECN field mask */
129#define IPTOS_ECN(cn) ((cn) & IPTOS_ECN_MASK)
130#define IPTOS_ECN_NOT_ECT 0x00
131
132/*
133 * Definitions for IP type of service per RFC1349 (ip_tos)
134 * DEPRECATED
135 */
136#define IPTOS_LOWDELAY 0x10
137#define IPTOS_THROUGHPUT 0x08
138#define IPTOS_RELIABILITY 0x04
139#define IPTOS_MINCOST 0x02
140/* ECN RFC3168 obsoletes RFC2481, and these will be deprecated soon. */
141#define IPTOS_CE 0x01 /* congestion experienced */
142#define IPTOS_ECT 0x02 /* ECN-capable transport */
143
144/*
145 * Definitions for IP precedence per RFC1195 (also in ip_tos) (hopefully unused)
146 */
147#define IPTOS_PREC_NETCONTROL 0xe0
148#define IPTOS_PREC_INTERNETCONTROL 0xc0
149#define IPTOS_PREC_CRITIC_ECP 0xa0
150#define IPTOS_PREC_FLASHOVERRIDE 0x80
151#define IPTOS_PREC_FLASH 0x60
152#define IPTOS_PREC_IMMEDIATE 0x40
153#define IPTOS_PREC_PRIORITY 0x20
154#define IPTOS_PREC_ROUTINE 0x00
155
156/*
157 * Definitions for options.
158 */
159#define IPOPT_COPIED(o) ((o)&0x80)
160#define IPOPT_CLASS(o) ((o)&0x60)
161#define IPOPT_NUMBER(o) ((o)&0x1f)
162
163#define IPOPT_CONTROL 0x00
164#define IPOPT_RESERVED1 0x20
165#define IPOPT_DEBMEAS 0x40
166#define IPOPT_RESERVED2 0x60
167
168#define IPOPT_EOL 0 /* end of option list */
169#define IPOPT_NOP 1 /* no operation */
170
171#define IPOPT_RR 7 /* record packet route */
172#define IPOPT_TS 68 /* timestamp */
173#define IPOPT_SECURITY 130 /* provide s,c,h,tcc */
174#define IPOPT_LSRR 131 /* loose source route */
175#define IPOPT_SATID 136 /* satnet id */
176#define IPOPT_SSRR 137 /* strict source route */
177
178/*
179 * Offsets to fields in options other than EOL and NOP.
180 */
181#define IPOPT_OPTVAL 0 /* option ID */
182#define IPOPT_OLEN 1 /* option length */
183#define IPOPT_OFFSET 2 /* offset within option */
184#define IPOPT_MINOFF 4 /* min value of above */
185
186/*
187 * Time stamp option structure.
188 */
189struct ip_timestamp {
190 u_int8_t ipt_code; /* IPOPT_TS */
191 u_int8_t ipt_len; /* size of structure (variable) */
192 u_int8_t ipt_ptr; /* index of current entry */
193#if BYTE_ORDER == LITTLE_ENDIAN
194 unsigned int ipt_flg:4, /* flags, see below */
195 ipt_oflw:4; /* overflow counter */
196#endif
197#if BYTE_ORDER == BIG_ENDIAN
198 unsigned int ipt_oflw:4, /* overflow counter */
199 ipt_flg:4; /* flags, see below */
200#endif
201 union ipt_timestamp {
202 n_time ipt_time[1];
203 struct ipt_ta {
204 struct in_addr ipt_addr;
205 n_time ipt_time;
206 } ipt_ta[1] __packed;
207 } ipt_timestamp __packed;
208} __packed;
209
210/* flag bits for ipt_flg */
211#define IPOPT_TS_TSONLY 0 /* timestamps only */
212#define IPOPT_TS_TSANDADDR 1 /* timestamps and addresses */
213#define IPOPT_TS_PRESPEC 3 /* specified modules only */
214
215/* bits for security (not byte swapped) */
216#define IPOPT_SECUR_UNCLASS 0x0000
217#define IPOPT_SECUR_CONFID 0xf135
218#define IPOPT_SECUR_EFTO 0x789a
219#define IPOPT_SECUR_MMMM 0xbc4d
220#define IPOPT_SECUR_RESTR 0xaf13
221#define IPOPT_SECUR_SECRET 0xd788
222#define IPOPT_SECUR_TOPSECRET 0x6bc5
223
224/*
225 * Internet implementation parameters.
226 */
227#define MAXTTL 255 /* maximum time to live (seconds) */
228#define IPDEFTTL 64 /* default ttl, from RFC 1340 */
229#define IPFRAGTTL 60 /* time to live for frags, slowhz */
230#define IPTTLDEC 1 /* subtracted when forwarding */
231
232#define IP_MSS 576 /* default maximum segment size */
233
234/*
235 * This is the real IPv4 pseudo header, used for computing the TCP and UDP
236 * checksums. For the Internet checksum, struct ipovly can be used instead.
237 * For stronger checksums, the real thing must be used.
238 */
239struct ippseudo {
240 struct in_addr ippseudo_src; /* source internet address */
241 struct in_addr ippseudo_dst; /* destination internet address */
242 u_int8_t ippseudo_pad; /* pad, must be zero */
243 u_int8_t ippseudo_p; /* protocol */
244 u_int16_t ippseudo_len; /* protocol length */
245} __packed;
246#endif /* !_NETINET_IP_H_ */
247