freebsd-dev/sys/netinet/ip.h
2007-05-11 11:00:48 +00:00

206 lines
6.6 KiB
C

/*-
* Copyright (c) 1982, 1986, 1993
* The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)ip.h 8.2 (Berkeley) 6/1/94
* $FreeBSD$
*/
#ifndef _NETINET_IP_H_
#define _NETINET_IP_H_
#include <sys/cdefs.h>
/*
* Definitions for internet protocol version 4.
*
* Per RFC 791, September 1981.
*/
#define IPVERSION 4
/*
* Structure of an internet header, naked of options.
*/
struct ip {
#if BYTE_ORDER == LITTLE_ENDIAN
u_int ip_hl:4, /* header length */
ip_v:4; /* version */
#endif
#if BYTE_ORDER == BIG_ENDIAN
u_int ip_v:4, /* version */
ip_hl:4; /* header length */
#endif
u_char ip_tos; /* type of service */
u_short ip_len; /* total length */
u_short ip_id; /* identification */
u_short ip_off; /* fragment offset field */
#define IP_RF 0x8000 /* reserved fragment flag */
#define IP_DF 0x4000 /* dont fragment flag */
#define IP_MF 0x2000 /* more fragments flag */
#define IP_OFFMASK 0x1fff /* mask for fragmenting bits */
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 */
} __packed __aligned(4);
#ifdef CTASSERT
CTASSERT(sizeof (struct ip) == 20);
#endif
#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
#define IPTOS_MINCOST 0x02
#if 1
/* ECN RFC3168 obsoletes RFC2481, and these will be deprecated soon. */
#define IPTOS_CE 0x01
#define IPTOS_ECT 0x02
#endif
/*
* 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
/*
* ECN (Explicit Congestion Notification) codepoints in RFC3168 mapped to the
* lower 2 bits of the TOS field.
*/
#define IPTOS_ECN_NOTECT 0x00 /* not-ECT */
#define IPTOS_ECN_ECT1 0x01 /* ECN-capable transport (1) */
#define IPTOS_ECN_ECT0 0x02 /* ECN-capable transport (0) */
#define IPTOS_ECN_CE 0x03 /* congestion experienced */
#define IPTOS_ECN_MASK 0x03 /* ECN field mask */
/*
* 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_ESO 133 /* extended security */
#define IPOPT_CIPSO 134 /* commerical security */
#define IPOPT_SATID 136 /* satnet id */
#define IPOPT_SSRR 137 /* strict source route */
#define IPOPT_RA 148 /* router alert */
/*
* 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 */
#if BYTE_ORDER == LITTLE_ENDIAN
u_int ipt_flg:4, /* flags, see below */
ipt_oflw:4; /* overflow counter */
#endif
#if BYTE_ORDER == BIG_ENDIAN
u_int 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 3 /* 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 IPDEFTTL 64 /* default ttl, from RFC 1340 */
#define IPFRAGTTL 60 /* time to live for frags, slowhz */
#define IPTTLDEC 1 /* subtracted when forwarding */
#define IP_MSS 576 /* default maximum segment size */
/*
* This is the real IPv4 pseudo header, used for computing the TCP and UDP
* checksums. For the Internet checksum, struct ipovly can be used instead.
* For stronger checksums, the real thing must be used.
*/
struct ippseudo {
struct in_addr ippseudo_src; /* source internet address */
struct in_addr ippseudo_dst; /* destination internet address */
u_char ippseudo_pad; /* pad, must be zero */
u_char ippseudo_p; /* protocol */
u_short ippseudo_len; /* protocol length */
};
#endif