ip.h revision 165966
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 * 4. 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: head/sys/netinet/ip.h 165966 2007-01-12 07:23:31Z imp $ 31 */ 32 33#ifndef _NETINET_IP_H_ 34#define _NETINET_IP_H_ 35 36#include <sys/cdefs.h> 37 38/* 39 * Definitions for internet protocol version 4. 40 * Per RFC 791, September 1981. 41 */ 42#define IPVERSION 4 43 44/* 45 * Structure of an internet header, naked of options. 46 */ 47struct ip { 48#if BYTE_ORDER == LITTLE_ENDIAN 49 u_int ip_hl:4, /* header length */ 50 ip_v:4; /* version */ 51#endif 52#if BYTE_ORDER == BIG_ENDIAN 53 u_int ip_v:4, /* version */ 54 ip_hl:4; /* header length */ 55#endif 56 u_char ip_tos; /* type of service */ 57 u_short ip_len; /* total length */ 58 u_short ip_id; /* identification */ 59 u_short ip_off; /* fragment offset field */ 60#define IP_RF 0x8000 /* reserved fragment flag */ 61#define IP_DF 0x4000 /* dont fragment flag */ 62#define IP_MF 0x2000 /* more fragments flag */ 63#define IP_OFFMASK 0x1fff /* mask for fragmenting bits */ 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} __packed __aligned(4); 69 70#ifdef CTASSERT 71CTASSERT(sizeof (struct ip) == 20); 72#endif 73 74#define IP_MAXPACKET 65535 /* maximum packet size */ 75 76/* 77 * Definitions for IP type of service (ip_tos) 78 */ 79#define IPTOS_LOWDELAY 0x10 80#define IPTOS_THROUGHPUT 0x08 81#define IPTOS_RELIABILITY 0x04 82#define IPTOS_MINCOST 0x02 83#if 1 84/* ECN RFC3168 obsoletes RFC2481, and these will be deprecated soon. */ 85#define IPTOS_CE 0x01 86#define IPTOS_ECT 0x02 87#endif 88 89/* 90 * Definitions for IP precedence (also in ip_tos) (hopefully unused) 91 */ 92#define IPTOS_PREC_NETCONTROL 0xe0 93#define IPTOS_PREC_INTERNETCONTROL 0xc0 94#define IPTOS_PREC_CRITIC_ECP 0xa0 95#define IPTOS_PREC_FLASHOVERRIDE 0x80 96#define IPTOS_PREC_FLASH 0x60 97#define IPTOS_PREC_IMMEDIATE 0x40 98#define IPTOS_PREC_PRIORITY 0x20 99#define IPTOS_PREC_ROUTINE 0x00 100 101/* 102 * ECN (Explicit Congestion Notification) codepoints in RFC3168 103 * mapped to the lower 2 bits of the TOS field. 104 */ 105#define IPTOS_ECN_NOTECT 0x00 /* not-ECT */ 106#define IPTOS_ECN_ECT1 0x01 /* ECN-capable transport (1) */ 107#define IPTOS_ECN_ECT0 0x02 /* ECN-capable transport (0) */ 108#define IPTOS_ECN_CE 0x03 /* congestion experienced */ 109#define IPTOS_ECN_MASK 0x03 /* ECN field mask */ 110 111/* 112 * Definitions for options. 113 */ 114#define IPOPT_COPIED(o) ((o)&0x80) 115#define IPOPT_CLASS(o) ((o)&0x60) 116#define IPOPT_NUMBER(o) ((o)&0x1f) 117 118#define IPOPT_CONTROL 0x00 119#define IPOPT_RESERVED1 0x20 120#define IPOPT_DEBMEAS 0x40 121#define IPOPT_RESERVED2 0x60 122 123#define IPOPT_EOL 0 /* end of option list */ 124#define IPOPT_NOP 1 /* no operation */ 125 126#define IPOPT_RR 7 /* record packet route */ 127#define IPOPT_TS 68 /* timestamp */ 128#define IPOPT_SECURITY 130 /* provide s,c,h,tcc */ 129#define IPOPT_LSRR 131 /* loose source route */ 130#define IPOPT_ESO 133 /* extended security */ 131#define IPOPT_CIPSO 134 /* commerical security */ 132#define IPOPT_SATID 136 /* satnet id */ 133#define IPOPT_SSRR 137 /* strict source route */ 134#define IPOPT_RA 148 /* router alert */ 135 136/* 137 * Offsets to fields in options other than EOL and NOP. 138 */ 139#define IPOPT_OPTVAL 0 /* option ID */ 140#define IPOPT_OLEN 1 /* option length */ 141#define IPOPT_OFFSET 2 /* offset within option */ 142#define IPOPT_MINOFF 4 /* min value of above */ 143 144/* 145 * Time stamp option structure. 146 */ 147struct ip_timestamp { 148 u_char ipt_code; /* IPOPT_TS */ 149 u_char ipt_len; /* size of structure (variable) */ 150 u_char ipt_ptr; /* index of current entry */ 151#if BYTE_ORDER == LITTLE_ENDIAN 152 u_int ipt_flg:4, /* flags, see below */ 153 ipt_oflw:4; /* overflow counter */ 154#endif 155#if BYTE_ORDER == BIG_ENDIAN 156 u_int ipt_oflw:4, /* overflow counter */ 157 ipt_flg:4; /* flags, see below */ 158#endif 159 union ipt_timestamp { 160 n_long ipt_time[1]; 161 struct ipt_ta { 162 struct in_addr ipt_addr; 163 n_long ipt_time; 164 } ipt_ta[1]; 165 } ipt_timestamp; 166}; 167 168/* flag bits for ipt_flg */ 169#define IPOPT_TS_TSONLY 0 /* timestamps only */ 170#define IPOPT_TS_TSANDADDR 1 /* timestamps and addresses */ 171#define IPOPT_TS_PRESPEC 3 /* specified modules only */ 172 173/* bits for security (not byte swapped) */ 174#define IPOPT_SECUR_UNCLASS 0x0000 175#define IPOPT_SECUR_CONFID 0xf135 176#define IPOPT_SECUR_EFTO 0x789a 177#define IPOPT_SECUR_MMMM 0xbc4d 178#define IPOPT_SECUR_RESTR 0xaf13 179#define IPOPT_SECUR_SECRET 0xd788 180#define IPOPT_SECUR_TOPSECRET 0x6bc5 181 182/* 183 * Internet implementation parameters. 184 */ 185#define MAXTTL 255 /* maximum time to live (seconds) */ 186#define IPDEFTTL 64 /* default ttl, from RFC 1340 */ 187#define IPFRAGTTL 60 /* time to live for frags, slowhz */ 188#define IPTTLDEC 1 /* subtracted when forwarding */ 189 190#define IP_MSS 576 /* default maximum segment size */ 191 192/* 193 * This is the real IPv4 pseudo header, used for computing the TCP and UDP 194 * checksums. For the Internet checksum, struct ipovly can be used instead. 195 * For stronger checksums, the real thing must be used. 196 */ 197struct ippseudo { 198 struct in_addr ippseudo_src; /* source internet address */ 199 struct in_addr ippseudo_dst; /* destination internet address */ 200 u_char ippseudo_pad; /* pad, must be zero */ 201 u_char ippseudo_p; /* protocol */ 202 u_short ippseudo_len; /* protocol length */ 203}; 204#endif 205