xref: /dragonfly/sys/netinet/ip.h (revision 277350a0)
1 /*
2  * Copyright (c) 1982, 1986, 1993
3  *	The Regents of the University of California.  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. 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.
16  *
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
27  * SUCH DAMAGE.
28  *
29  *	@(#)ip.h	8.2 (Berkeley) 6/1/94
30  * $FreeBSD: src/sys/netinet/ip.h,v 1.17 1999/12/22 19:13:20 shin Exp $
31  */
32 
33 #ifndef _NETINET_IP_H_
34 #define _NETINET_IP_H_
35 
36 #ifndef _SYS_TYPES_H_
37 #include <sys/types.h>
38 #endif
39 #ifndef _NETINET_IN_H_
40 #include <netinet/in.h>
41 #endif
42 #ifndef _NETINET_IN_SYSTM_H_
43 #include <netinet/in_systm.h>
44 #endif
45 #include <machine/endian.h>
46 
47 /*
48  * Definitions for internet protocol version 4.
49  * Per RFC 791, September 1981.
50  */
51 #define	IPVERSION	4
52 
53 /*
54  * Structure of an internet header, naked of options.
55  */
56 struct ip {
57 #ifdef _IP_VHL
58 	u_char	ip_vhl;			/* version << 4 | header length >> 2 */
59 #elif _BYTE_ORDER == _LITTLE_ENDIAN
60 	u_int	ip_hl:4,		/* header length */
61 		ip_v:4;			/* version */
62 #elif _BYTE_ORDER == _BIG_ENDIAN
63 	u_int	ip_v:4,			/* version */
64 		ip_hl:4;		/* header length */
65 #else
66 #error "Byte order not implemented"
67 #endif
68 	u_char	ip_tos;			/* type of service */
69 	u_short	ip_len;			/* total length */
70 	u_short	ip_id;			/* identification */
71 	u_short	ip_off;			/* fragment offset field */
72 #define	IP_RF 0x8000			/* reserved fragment flag */
73 #define	IP_DF 0x4000			/* dont fragment flag */
74 #define	IP_MF 0x2000			/* more fragments flag */
75 #define	IP_OFFMASK 0x1fff		/* mask for fragmenting bits */
76 	u_char	ip_ttl;			/* time to live */
77 	u_char	ip_p;			/* protocol */
78 	u_short	ip_sum;			/* checksum */
79 	struct	in_addr ip_src,ip_dst;	/* source and dest address */
80 };
81 
82 #ifdef _IP_VHL
83 #define	IP_MAKE_VHL(v, hl)	((v) << 4 | (hl))
84 #define	IP_VHL_HL(vhl)		((vhl) & 0x0f)
85 #define	IP_VHL_V(vhl)		((vhl) >> 4)
86 #define	IP_VHL_BORING		0x45
87 #endif
88 
89 #define	IP_MAXPACKET	65535		/* maximum packet size */
90 
91 /*
92  * Definitions for IP type of service (ip_tos)
93  */
94 #define	IPTOS_LOWDELAY		0x10
95 #define	IPTOS_THROUGHPUT	0x08
96 #define	IPTOS_RELIABILITY	0x04
97 #define	IPTOS_MINCOST		0x02
98 #if 1
99 /* ECN RFC3168 obsoletes RFC2481, and these will be deprecated soon. */
100 #define	IPTOS_CE		0x01	/* congestion experienced */
101 #define	IPTOS_ECT		0x02	/* ECN-capable transport */
102 #endif
103 
104 
105 /*
106  * Definitions for IP precedence (also in ip_tos) (hopefully unused)
107  */
108 #define	IPTOS_PREC_NETCONTROL		0xe0
109 #define	IPTOS_PREC_INTERNETCONTROL	0xc0
110 #define	IPTOS_PREC_CRITIC_ECP		0xa0
111 #define	IPTOS_PREC_FLASHOVERRIDE	0x80
112 #define	IPTOS_PREC_FLASH		0x60
113 #define	IPTOS_PREC_IMMEDIATE		0x40
114 #define	IPTOS_PREC_PRIORITY		0x20
115 #define	IPTOS_PREC_ROUTINE		0x00
116 
117 /*
118  * ECN (Explicit Congestion Notification) codepoints in RFC3168
119  * mapped to the lower 2 bits of the TOS field.
120  */
121 #define	IPTOS_ECN_NOTECT	0x00	/* not-ECT */
122 #define	IPTOS_ECN_ECT1		0x01	/* ECN-capable transport (1) */
123 #define	IPTOS_ECN_ECT0		0x02	/* ECN-capable transport (0) */
124 #define	IPTOS_ECN_CE		0x03	/* congestion experienced */
125 #define	IPTOS_ECN_MASK		0x03	/* ECN field mask */
126 
127 /*
128  * Definitions for options.
129  */
130 #define	IPOPT_COPIED(o)		((o)&0x80)
131 #define	IPOPT_CLASS(o)		((o)&0x60)
132 #define	IPOPT_NUMBER(o)		((o)&0x1f)
133 
134 #define	IPOPT_CONTROL		0x00
135 #define	IPOPT_RESERVED1		0x20
136 #define	IPOPT_DEBMEAS		0x40
137 #define	IPOPT_RESERVED2		0x60
138 
139 #define	IPOPT_EOL		0		/* end of option list */
140 #define	IPOPT_NOP		1		/* no operation */
141 
142 #define	IPOPT_RR		7		/* record packet route */
143 #define	IPOPT_TS		68		/* timestamp */
144 #define	IPOPT_SECURITY		130		/* provide s,c,h,tcc */
145 #define	IPOPT_LSRR		131		/* loose source route */
146 #define	IPOPT_SATID		136		/* satnet id */
147 #define	IPOPT_SSRR		137		/* strict source route */
148 #define	IPOPT_RA		148		/* router alert */
149 
150 /*
151  * Offsets to fields in options other than EOL and NOP.
152  */
153 #define	IPOPT_OPTVAL		0		/* option ID */
154 #define	IPOPT_OLEN		1		/* option length */
155 #define IPOPT_OFFSET		2		/* offset within option */
156 #define	IPOPT_MINOFF		4		/* min value of above */
157 
158 /*
159  * Time stamp option structure.
160  */
161 struct	ip_timestamp {
162 	u_char	ipt_code;		/* IPOPT_TS */
163 	u_char	ipt_len;		/* size of structure (variable) */
164 	u_char	ipt_ptr;		/* index of current entry */
165 #if _BYTE_ORDER == _LITTLE_ENDIAN
166 	u_int	ipt_flg:4,		/* flags, see below */
167 		ipt_oflw:4;		/* overflow counter */
168 #elif _BYTE_ORDER == _BIG_ENDIAN
169 	u_int	ipt_oflw:4,		/* overflow counter */
170 		ipt_flg:4;		/* flags, see below */
171 #else
172 #error "Byte order not implemented"
173 #endif
174 	union ipt_timestamp {
175 		n_long	ipt_time[1];
176 		struct	ipt_ta {
177 			struct in_addr ipt_addr;
178 			n_long ipt_time;
179 		} ipt_ta[1];
180 	} ipt_timestamp;
181 };
182 
183 /* flag bits for ipt_flg */
184 #define	IPOPT_TS_TSONLY		0		/* timestamps only */
185 #define	IPOPT_TS_TSANDADDR	1		/* timestamps and addresses */
186 #define	IPOPT_TS_PRESPEC	3		/* specified modules only */
187 
188 /* bits for security (not byte swapped) */
189 #define	IPOPT_SECUR_UNCLASS	0x0000
190 #define	IPOPT_SECUR_CONFID	0xf135
191 #define	IPOPT_SECUR_EFTO	0x789a
192 #define	IPOPT_SECUR_MMMM	0xbc4d
193 #define	IPOPT_SECUR_RESTR	0xaf13
194 #define	IPOPT_SECUR_SECRET	0xd788
195 #define	IPOPT_SECUR_TOPSECRET	0x6bc5
196 
197 /*
198  * Internet implementation parameters.
199  */
200 #define	MAXTTL		255		/* maximum time to live (seconds) */
201 #define	IPDEFTTL	64		/* default ttl, from RFC 1340 */
202 #define	IPFRAGTTL	60		/* time to live for frags, slowhz */
203 #define	IPTTLDEC	1		/* subtracted when forwarding */
204 
205 #define	IP_MSS		576		/* default maximum segment size */
206 
207 /*
208  * This is the real IPv4 pseudo header, used for computing the TCP and UDP
209  * checksums. For the Internet checksum, struct ipovly can be used instead.
210  * For stronger checksums, the real thing must be used.
211  */
212 struct ippseudo {
213 	struct	in_addr	ippseudo_src;	/* source internet address */
214 	struct	in_addr	ippseudo_dst;	/* destination internet address */
215 	u_int8_t	ippseudo_pad;	/* pad, must be zero */
216 	u_int8_t	ippseudo_p;	/* protocol */
217 	u_int16_t	ippseudo_len;	/* protocol length */
218 } __packed;
219 #endif
220