xref: /dragonfly/sys/netinet/ip.h (revision 0db87cb7)
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. 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	8.2 (Berkeley) 6/1/94
34  * $FreeBSD: src/sys/netinet/ip.h,v 1.17 1999/12/22 19:13:20 shin Exp $
35  */
36 
37 #ifndef _NETINET_IP_H_
38 #define _NETINET_IP_H_
39 
40 #ifndef _SYS_TYPES_H_
41 #include <sys/types.h>
42 #endif
43 #ifndef _NETINET_IN_H_
44 #include <netinet/in.h>
45 #endif
46 #ifndef _NETINET_IN_SYSTM_H_
47 #include <netinet/in_systm.h>
48 #endif
49 #include <machine/endian.h>
50 
51 /*
52  * Definitions for internet protocol version 4.
53  * Per RFC 791, September 1981.
54  */
55 #define	IPVERSION	4
56 
57 /*
58  * Structure of an internet header, naked of options.
59  */
60 struct ip {
61 #ifdef _IP_VHL
62 	u_char	ip_vhl;			/* version << 4 | header length >> 2 */
63 #elif _BYTE_ORDER == _LITTLE_ENDIAN
64 	u_int	ip_hl:4,		/* header length */
65 		ip_v:4;			/* version */
66 #elif _BYTE_ORDER == _BIG_ENDIAN
67 	u_int	ip_v:4,			/* version */
68 		ip_hl:4;		/* header length */
69 #else
70 #error "Byte order not implemented"
71 #endif
72 	u_char	ip_tos;			/* type of service */
73 	u_short	ip_len;			/* total length */
74 	u_short	ip_id;			/* identification */
75 	u_short	ip_off;			/* fragment offset field */
76 #define	IP_RF 0x8000			/* reserved fragment flag */
77 #define	IP_DF 0x4000			/* dont fragment flag */
78 #define	IP_MF 0x2000			/* more fragments flag */
79 #define	IP_OFFMASK 0x1fff		/* mask for fragmenting bits */
80 	u_char	ip_ttl;			/* time to live */
81 	u_char	ip_p;			/* protocol */
82 	u_short	ip_sum;			/* checksum */
83 	struct	in_addr ip_src,ip_dst;	/* source and dest address */
84 };
85 
86 #ifdef _IP_VHL
87 #define	IP_MAKE_VHL(v, hl)	((v) << 4 | (hl))
88 #define	IP_VHL_HL(vhl)		((vhl) & 0x0f)
89 #define	IP_VHL_V(vhl)		((vhl) >> 4)
90 #define	IP_VHL_BORING		0x45
91 #endif
92 
93 #define	IP_MAXPACKET	65535		/* maximum packet size */
94 
95 /*
96  * Definitions for IP type of service (ip_tos)
97  */
98 #define	IPTOS_LOWDELAY		0x10
99 #define	IPTOS_THROUGHPUT	0x08
100 #define	IPTOS_RELIABILITY	0x04
101 #define	IPTOS_MINCOST		0x02
102 #if 1
103 /* ECN RFC3168 obsoletes RFC2481, and these will be deprecated soon. */
104 #define	IPTOS_CE		0x01	/* congestion experienced */
105 #define	IPTOS_ECT		0x02	/* ECN-capable transport */
106 #endif
107 
108 
109 /*
110  * Definitions for IP precedence (also in ip_tos) (hopefully unused)
111  */
112 #define	IPTOS_PREC_NETCONTROL		0xe0
113 #define	IPTOS_PREC_INTERNETCONTROL	0xc0
114 #define	IPTOS_PREC_CRITIC_ECP		0xa0
115 #define	IPTOS_PREC_FLASHOVERRIDE	0x80
116 #define	IPTOS_PREC_FLASH		0x60
117 #define	IPTOS_PREC_IMMEDIATE		0x40
118 #define	IPTOS_PREC_PRIORITY		0x20
119 #define	IPTOS_PREC_ROUTINE		0x00
120 
121 /*
122  * ECN (Explicit Congestion Notification) codepoints in RFC3168
123  * mapped to the lower 2 bits of the TOS field.
124  */
125 #define	IPTOS_ECN_NOTECT	0x00	/* not-ECT */
126 #define	IPTOS_ECN_ECT1		0x01	/* ECN-capable transport (1) */
127 #define	IPTOS_ECN_ECT0		0x02	/* ECN-capable transport (0) */
128 #define	IPTOS_ECN_CE		0x03	/* congestion experienced */
129 #define	IPTOS_ECN_MASK		0x03	/* ECN field mask */
130 
131 /*
132  * Definitions for options.
133  */
134 #define	IPOPT_COPIED(o)		((o)&0x80)
135 #define	IPOPT_CLASS(o)		((o)&0x60)
136 #define	IPOPT_NUMBER(o)		((o)&0x1f)
137 
138 #define	IPOPT_CONTROL		0x00
139 #define	IPOPT_RESERVED1		0x20
140 #define	IPOPT_DEBMEAS		0x40
141 #define	IPOPT_RESERVED2		0x60
142 
143 #define	IPOPT_EOL		0		/* end of option list */
144 #define	IPOPT_NOP		1		/* no operation */
145 
146 #define	IPOPT_RR		7		/* record packet route */
147 #define	IPOPT_TS		68		/* timestamp */
148 #define	IPOPT_SECURITY		130		/* provide s,c,h,tcc */
149 #define	IPOPT_LSRR		131		/* loose source route */
150 #define	IPOPT_SATID		136		/* satnet id */
151 #define	IPOPT_SSRR		137		/* strict source route */
152 #define	IPOPT_RA		148		/* router alert */
153 
154 /*
155  * Offsets to fields in options other than EOL and NOP.
156  */
157 #define	IPOPT_OPTVAL		0		/* option ID */
158 #define	IPOPT_OLEN		1		/* option length */
159 #define IPOPT_OFFSET		2		/* offset within option */
160 #define	IPOPT_MINOFF		4		/* min value of above */
161 
162 /*
163  * Time stamp option structure.
164  */
165 struct	ip_timestamp {
166 	u_char	ipt_code;		/* IPOPT_TS */
167 	u_char	ipt_len;		/* size of structure (variable) */
168 	u_char	ipt_ptr;		/* index of current entry */
169 #if _BYTE_ORDER == _LITTLE_ENDIAN
170 	u_int	ipt_flg:4,		/* flags, see below */
171 		ipt_oflw:4;		/* overflow counter */
172 #elif _BYTE_ORDER == _BIG_ENDIAN
173 	u_int	ipt_oflw:4,		/* overflow counter */
174 		ipt_flg:4;		/* flags, see below */
175 #else
176 #error "Byte order not implemented"
177 #endif
178 	union ipt_timestamp {
179 		n_long	ipt_time[1];
180 		struct	ipt_ta {
181 			struct in_addr ipt_addr;
182 			n_long ipt_time;
183 		} ipt_ta[1];
184 	} ipt_timestamp;
185 };
186 
187 /* flag bits for ipt_flg */
188 #define	IPOPT_TS_TSONLY		0		/* timestamps only */
189 #define	IPOPT_TS_TSANDADDR	1		/* timestamps and addresses */
190 #define	IPOPT_TS_PRESPEC	3		/* specified modules only */
191 
192 /* bits for security (not byte swapped) */
193 #define	IPOPT_SECUR_UNCLASS	0x0000
194 #define	IPOPT_SECUR_CONFID	0xf135
195 #define	IPOPT_SECUR_EFTO	0x789a
196 #define	IPOPT_SECUR_MMMM	0xbc4d
197 #define	IPOPT_SECUR_RESTR	0xaf13
198 #define	IPOPT_SECUR_SECRET	0xd788
199 #define	IPOPT_SECUR_TOPSECRET	0x6bc5
200 
201 /*
202  * Internet implementation parameters.
203  */
204 #define	MAXTTL		255		/* maximum time to live (seconds) */
205 #define	IPDEFTTL	64		/* default ttl, from RFC 1340 */
206 #define	IPFRAGTTL	60		/* time to live for frags, slowhz */
207 #define	IPTTLDEC	1		/* subtracted when forwarding */
208 
209 #define	IP_MSS		576		/* default maximum segment size */
210 
211 /*
212  * This is the real IPv4 pseudo header, used for computing the TCP and UDP
213  * checksums. For the Internet checksum, struct ipovly can be used instead.
214  * For stronger checksums, the real thing must be used.
215  */
216 struct ippseudo {
217 	struct	in_addr	ippseudo_src;	/* source internet address */
218 	struct	in_addr	ippseudo_dst;	/* destination internet address */
219 	u_int8_t	ippseudo_pad;	/* pad, must be zero */
220 	u_int8_t	ippseudo_p;	/* protocol */
221 	u_int16_t	ippseudo_len;	/* protocol length */
222 } __packed;
223 #endif
224