Home | History | Annotate | Line # | Download | only in netinet
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