xref: /openbsd/sys/netinet/ip.h (revision 7cf98560)
1 /*	$OpenBSD: ip.h,v 1.20 2021/12/14 23:47:36 dtucker Exp $	*/
2 /*	$NetBSD: ip.h,v 1.9 1995/05/15 01:22:44 cgd Exp $	*/
3 
4 /*
5  * Copyright (c) 1982, 1986, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  *	@(#)ip.h	8.1 (Berkeley) 6/10/93
33  */
34 
35 #ifndef _NETINET_IP_H_
36 #define _NETINET_IP_H_
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_int     ip_hl:4,		/* header length */
50 		  ip_v:4;		/* version */
51 #endif
52 #if _BYTE_ORDER == _BIG_ENDIAN
53 	u_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_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 #if 1
80 /* ECN RFC3168 obsoletes RFC2481, and these will be deprecated soon. */
81 #define	IPTOS_CE		0x01	/* congestion experienced */
82 #define	IPTOS_ECT		0x02	/* ECN-capable transport */
83 #endif
84 
85 /*
86  * Definitions for IP precedence (also in ip_tos) (hopefully unused)
87  */
88 #define	IPTOS_PREC_NETCONTROL		0xe0
89 #define	IPTOS_PREC_INTERNETCONTROL	0xc0
90 #define	IPTOS_PREC_CRITIC_ECP		0xa0
91 #define	IPTOS_PREC_FLASHOVERRIDE	0x80
92 #define	IPTOS_PREC_FLASH		0x60
93 #define	IPTOS_PREC_IMMEDIATE		0x40
94 #define	IPTOS_PREC_PRIORITY		0x20
95 #define	IPTOS_PREC_ROUTINE		0x00
96 
97 /*
98  * Definitions for DiffServ Codepoints as per RFCs 2474, 3246, 4594 & 8622.
99  * These are the 6 most significant bits as they appear on the wire, so the
100  * two least significant bits must be zero.
101  */
102 #define	IPTOS_DSCP_CS0		0x00
103 #define	IPTOS_DSCP_LE		0x04
104 #define	IPTOS_DSCP_CS1		0x20
105 #define	IPTOS_DSCP_AF11		0x28
106 #define	IPTOS_DSCP_AF12		0x30
107 #define	IPTOS_DSCP_AF13		0x38
108 #define	IPTOS_DSCP_CS2		0x40
109 #define	IPTOS_DSCP_AF21		0x48
110 #define	IPTOS_DSCP_AF22		0x50
111 #define	IPTOS_DSCP_AF23		0x58
112 #define	IPTOS_DSCP_CS3		0x60
113 #define	IPTOS_DSCP_AF31		0x68
114 #define	IPTOS_DSCP_AF32		0x70
115 #define	IPTOS_DSCP_AF33		0x78
116 #define	IPTOS_DSCP_CS4		0x80
117 #define	IPTOS_DSCP_AF41		0x88
118 #define	IPTOS_DSCP_AF42		0x90
119 #define	IPTOS_DSCP_AF43		0x98
120 #define	IPTOS_DSCP_CS5		0xa0
121 #define	IPTOS_DSCP_EF		0xb8
122 #define	IPTOS_DSCP_CS6		0xc0
123 #define	IPTOS_DSCP_CS7		0xe0
124 
125 /*
126  * ECN (Explicit Congestion Notification) codepoints in RFC3168
127  * mapped to the lower 2 bits of the TOS field.
128  */
129 #define	IPTOS_ECN_NOTECT	0x00	/* not-ECT */
130 #define	IPTOS_ECN_ECT1		0x01	/* ECN-capable transport (1) */
131 #define	IPTOS_ECN_ECT0		0x02	/* ECN-capable transport (0) */
132 #define	IPTOS_ECN_CE		0x03	/* congestion experienced */
133 #define	IPTOS_ECN_MASK		0x03	/* ECN field mask */
134 
135 /*
136  * Definitions for options.
137  */
138 #define	IPOPT_COPIED(o)		((o)&0x80)
139 #define	IPOPT_CLASS(o)		((o)&0x60)
140 #define	IPOPT_NUMBER(o)		((o)&0x1f)
141 
142 #define	IPOPT_CONTROL		0x00
143 #define	IPOPT_RESERVED1		0x20
144 #define	IPOPT_DEBMEAS		0x40
145 #define	IPOPT_RESERVED2		0x60
146 
147 #define	IPOPT_EOL		0		/* end of option list */
148 #define	IPOPT_NOP		1		/* no operation */
149 
150 #define	IPOPT_RR		7		/* record packet route */
151 #define	IPOPT_TS		68		/* timestamp */
152 #define	IPOPT_SECURITY		130		/* provide s,c,h,tcc */
153 #define	IPOPT_LSRR		131		/* loose source route */
154 #define	IPOPT_SATID		136		/* satnet id */
155 #define	IPOPT_SSRR		137		/* strict source route */
156 #define	IPOPT_RA		148		/* router alert */
157 
158 /*
159  * Offsets to fields in options other than EOL and NOP.
160  */
161 #define	IPOPT_OPTVAL		0		/* option ID */
162 #define	IPOPT_OLEN		1		/* option length */
163 #define	IPOPT_OFFSET		2		/* offset within option */
164 #define	IPOPT_MINOFF		4		/* min value of above */
165 
166 /*
167  * Time stamp option structure.
168  */
169 struct	ip_timestamp {
170 	u_int8_t ipt_code;		/* IPOPT_TS */
171 	u_int8_t ipt_len;		/* size of structure (variable) */
172 	u_int8_t ipt_ptr;		/* index of current entry */
173 #if _BYTE_ORDER == _LITTLE_ENDIAN
174 	u_int    ipt_flg:4,		/* flags, see below */
175 		 ipt_oflw:4;		/* overflow counter */
176 #endif
177 #if _BYTE_ORDER == _BIG_ENDIAN
178 	u_int    ipt_oflw:4,		/* overflow counter */
179 		 ipt_flg:4;		/* flags, see below */
180 #endif
181 	union ipt_timestamp {
182 		 u_int32_t ipt_time[1];
183 		 struct	ipt_ta {
184 			struct in_addr ipt_addr;
185 			u_int32_t ipt_time;
186 		 } ipt_ta[1];
187 	} ipt_timestamp;
188 };
189 
190 /* flag bits for ipt_flg */
191 #define	IPOPT_TS_TSONLY		0		/* timestamps only */
192 #define	IPOPT_TS_TSANDADDR	1		/* timestamps and addresses */
193 #define	IPOPT_TS_PRESPEC	3		/* specified modules only */
194 
195 /* bits for security (not byte swapped) */
196 #define	IPOPT_SECUR_UNCLASS	0x0000
197 #define	IPOPT_SECUR_CONFID	0xf135
198 #define	IPOPT_SECUR_EFTO	0x789a
199 #define	IPOPT_SECUR_MMMM	0xbc4d
200 #define	IPOPT_SECUR_RESTR	0xaf13
201 #define	IPOPT_SECUR_SECRET	0xd788
202 #define	IPOPT_SECUR_TOPSECRET	0x6bc5
203 
204 /*
205  * Internet implementation parameters.
206  */
207 #define	MAXTTL		255		/* maximum time to live (seconds) */
208 #define	IPDEFTTL	64		/* default ttl, from RFC 1340 */
209 #define	IPFRAGTTL	60		/* time to live for frags, slowhz */
210 #define	IPTTLDEC	1		/* subtracted when forwarding */
211 
212 #define	IP_MSS		576		/* default maximum segment size */
213 
214 #ifdef _KERNEL
215 
216 /* Maximum length for IP protocol queues */
217 #define IPQ_MAXLEN	2048
218 
219 /*
220  * This is the real IPv4 pseudo header, used for computing the TCP and UDP
221  * checksums. For the Internet checksum, struct ipovly can be used instead.
222  * For stronger checksums, the real thing must be used.
223  */
224 struct ippseudo {
225 	struct    in_addr ippseudo_src;	/* source internet address */
226 	struct    in_addr ippseudo_dst;	/* destination internet address */
227 	u_int8_t  ippseudo_pad;		/* pad, must be zero */
228 	u_int8_t  ippseudo_p;		/* protocol */
229 	u_int16_t ippseudo_len;		/* protocol length */
230 };
231 #endif /* _KERNEL */
232 
233 #endif /* _NETINET_IP_H_ */
234