/* IP.H

 * 

 */

/** @file

@publishedAll

@released

*/

/*

 * Copyright (c) 1982, 1986 Regents of the University of California.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms are permitted

 * provided that this notice is preserved and that due credit is given

 * to the University of California at Berkeley. The name of the University

 * may not be used to endorse or promote products derived from this

 * software without specific prior written permission. This software

 * is provided ``as is'' without express or implied warranty.

 */

/*

 * Definitions for internet protocol version 4.

 * Per RFC 791, September 1981.

 */

#ifndef	_NETINET_IP_H

#define	_NETINET_IP_H

#ifdef	__cplusplus

extern "C" {

#endif

#define	IPVERSION	4

/**

Structure of an internet header, naked of options.

We declare ip_len and ip_off to be short, rather than u_short

pragmatically since otherwise unsigned comparisons can result

against negative integers quite easily, and fail in subtle ways.

*/

struct ip {

#ifdef _BIT_FIELDS_LTOH

	u_char	ip_hl:4,		/* header length */

		ip_v:4;			/* version */

#else

	u_char	ip_v:4,			/* version */

		ip_hl:4;		/* header length */

#endif

	u_char	ip_tos;			/* type of service */

	short	ip_len;			/* total length */

	u_short	ip_id;			/* identification */

	short	ip_off;			/* fragment offset field */

#define	IP_DF 0x4000			/* dont fragment flag */

#define	IP_MF 0x2000			/* more fragments flag */

	u_char	ip_ttl;			/* time to live */

	u_char	ip_p;			/* protocol */

	u_short	ip_sum;			/* checksum */

	struct	in_addr ip_src, ip_dst;	/* source and dest address */

};

#define	IP_MAXPACKET	65535		/* maximum packet size */

/**

Definitions for IP type of service (ip_tos)

*/

#define	IPTOS_LOWDELAY		0x10

#define	IPTOS_THROUGHPUT	0x08

#define	IPTOS_RELIABILITY	0x04

/**

Definitions for IP precedence (also in ip_tos) (hopefully unused)

*/

#define	IPTOS_PREC_NETCONTROL		0xe0

#define	IPTOS_PREC_INTERNETCONTROL	0xc0

#define	IPTOS_PREC_CRITIC_ECP		0xa0

#define	IPTOS_PREC_FLASHOVERRIDE	0x80

#define	IPTOS_PREC_FLASH		0x60

#define	IPTOS_PREC_IMMEDIATE		0x40

#define	IPTOS_PREC_PRIORITY		0x20

#define	IPTOS_PREC_ROUTINE		0x00

/**

Definitions for options.

*/

#define	IPOPT_COPIED(o)		((o)&0x80)

#define	IPOPT_CLASS(o)		((o)&0x60)

#define	IPOPT_NUMBER(o)		((o)&0x1f)

#define	IPOPT_CONTROL		0x00

#define	IPOPT_RESERVED1		0x20

#define	IPOPT_DEBMEAS		0x40

#define	IPOPT_RESERVED2		0x60

#define	IPOPT_EOL		0		/* end of option list */

#define	IPOPT_NOP		1		/* no operation */

#define	IPOPT_RR		7		/* record packet route */

#define	IPOPT_TS		68		/* timestamp */

#define	IPOPT_SECURITY		130		/* provide s,c,h,tcc */

#define	IPOPT_LSRR		131		/* loose source route */

#define	IPOPT_SATID		136		/* satnet id */

#define	IPOPT_SSRR		137		/* strict source route */

/**

Offsets to fields in options other than EOL and NOP.

*/

#define	IPOPT_OPTVAL		0		/* option ID */

#define	IPOPT_OLEN		1		/* option length */

#define	IPOPT_OFFSET		2		/* offset within option */

#define	IPOPT_MINOFF		4		/* min value of above */

/**

Time stamp option structure.

*/

struct	ip_timestamp {

	u_char	ipt_code;		/* IPOPT_TS */

	u_char	ipt_len;		/* size of structure (variable) */

	u_char	ipt_ptr;		/* index of current entry */

#ifdef _BIT_FIELDS_LTOH

	u_char	ipt_flg:4,		/* flags, see below */

		ipt_oflw:4;		/* overflow counter */

#else

	u_char	ipt_oflw:4,		/* overflow counter */

		ipt_flg:4;		/* flags, see below */

#endif

	union ipt_timestamp {

		n_long	ipt_time[1];

		struct	ipt_ta {

			struct in_addr ipt_addr;

			n_long ipt_time;

		} ipt_ta[1];

	} ipt_timestamp;

};

/**

flag bits for ipt_flg 

*/

#define	IPOPT_TS_TSONLY		0		/* timestamps only */

#define	IPOPT_TS_TSANDADDR	1		/* timestamps and addresses */

#define	IPOPT_TS_PRESPEC	2		/* specified modules only */

/** 

bits for security (not byte swapped) 

*/

#define	IPOPT_SECUR_UNCLASS	0x0000

#define	IPOPT_SECUR_CONFID	0xf135

#define	IPOPT_SECUR_EFTO	0x789a

#define	IPOPT_SECUR_MMMM	0xbc4d

#define	IPOPT_SECUR_RESTR	0xaf13

#define	IPOPT_SECUR_SECRET	0xd788

#define	IPOPT_SECUR_TOPSECRET	0x6bc5

/**

Internet implementation parameters.

*/

#define	MAXTTL		255		/* maximum time to live (seconds) */

#define	IPFRAGTTL	60		/* time to live for frags, slowhz */

#define	IPTTLDEC	1		/* subtracted when forwarding */

#define	IP_MSS		576		/* default maximum segment size */

#ifdef	__cplusplus

}

#endif

#endif	/* _NETINET_IP_H */