ip.h revision 285275
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 */ 35 36#ifndef TCPDUMP_IP_H 37#define TCPDUMP_IP_H 38 39#include "tcpdump-stdinc.h" 40 41/* 42 * Definitions for internet protocol version 4. 43 * Per RFC 791, September 1981. 44 */ 45#define IPVERSION 4 46 47/* 48 * Structure of an internet header, naked of options. 49 * 50 * We declare ip_len and ip_off to be short, rather than u_short 51 * pragmatically since otherwise unsigned comparisons can result 52 * against negative integers quite easily, and fail in subtle ways. 53 */ 54struct ip { 55 uint8_t ip_vhl; /* header length, version */ 56#define IP_V(ip) (((ip)->ip_vhl & 0xf0) >> 4) 57#define IP_HL(ip) ((ip)->ip_vhl & 0x0f) 58 uint8_t ip_tos; /* type of service */ 59 uint16_t ip_len; /* total length */ 60 uint16_t ip_id; /* identification */ 61 uint16_t ip_off; /* fragment offset field */ 62#define IP_DF 0x4000 /* dont fragment flag */ 63#define IP_MF 0x2000 /* more fragments flag */ 64#define IP_OFFMASK 0x1fff /* mask for fragmenting bits */ 65 uint8_t ip_ttl; /* time to live */ 66 uint8_t ip_p; /* protocol */ 67 uint16_t ip_sum; /* checksum */ 68 struct in_addr ip_src,ip_dst; /* source and dest address */ 69} UNALIGNED; 70 71#define IP_MAXPACKET 65535 /* maximum packet size */ 72 73/* 74 * Definitions for IP type of service (ip_tos) 75 */ 76#define IPTOS_LOWDELAY 0x10 77#define IPTOS_THROUGHPUT 0x08 78#define IPTOS_RELIABILITY 0x04 79 80/* 81 * Definitions for IP precedence (also in ip_tos) (hopefully unused) 82 */ 83#define IPTOS_PREC_NETCONTROL 0xe0 84#define IPTOS_PREC_INTERNETCONTROL 0xc0 85#define IPTOS_PREC_CRITIC_ECP 0xa0 86#define IPTOS_PREC_FLASHOVERRIDE 0x80 87#define IPTOS_PREC_FLASH 0x60 88#define IPTOS_PREC_IMMEDIATE 0x40 89#define IPTOS_PREC_PRIORITY 0x20 90#define IPTOS_PREC_ROUTINE 0x00 91 92/* 93 * Definitions for options. 94 */ 95#define IPOPT_COPIED(o) ((o)&0x80) 96#define IPOPT_CLASS(o) ((o)&0x60) 97#define IPOPT_NUMBER(o) ((o)&0x1f) 98 99#define IPOPT_CONTROL 0x00 100#define IPOPT_RESERVED1 0x20 101#define IPOPT_DEBMEAS 0x40 102#define IPOPT_RESERVED2 0x60 103 104#define IPOPT_EOL 0 /* end of option list */ 105#define IPOPT_NOP 1 /* no operation */ 106 107#define IPOPT_RR 7 /* record packet route */ 108#define IPOPT_TS 68 /* timestamp */ 109#define IPOPT_RFC1393 82 /* traceroute RFC 1393 */ 110#define IPOPT_SECURITY 130 /* provide s,c,h,tcc */ 111#define IPOPT_LSRR 131 /* loose source route */ 112#define IPOPT_SATID 136 /* satnet id */ 113#define IPOPT_SSRR 137 /* strict source route */ 114#define IPOPT_RA 148 /* router-alert, rfc2113 */ 115 116/* 117 * Offsets to fields in options other than EOL and NOP. 118 */ 119#define IPOPT_OPTVAL 0 /* option ID */ 120#define IPOPT_OLEN 1 /* option length */ 121#define IPOPT_OFFSET 2 /* offset within option */ 122#define IPOPT_MINOFF 4 /* min value of above */ 123 124/* 125 * Time stamp option structure. 126 */ 127struct ip_timestamp { 128 uint8_t ipt_code; /* IPOPT_TS */ 129 uint8_t ipt_len; /* size of structure (variable) */ 130 uint8_t ipt_ptr; /* index of current entry */ 131 uint8_t ipt_oflwflg; /* flags, overflow counter */ 132#define IPTS_OFLW(ip) (((ipt)->ipt_oflwflg & 0xf0) >> 4) 133#define IPTS_FLG(ip) ((ipt)->ipt_oflwflg & 0x0f) 134 union ipt_timestamp { 135 uint32_t ipt_time[1]; 136 struct ipt_ta { 137 struct in_addr ipt_addr; 138 uint32_t ipt_time; 139 } ipt_ta[1]; 140 } ipt_timestamp; 141} UNALIGNED; 142 143/* flag bits for ipt_flg */ 144#define IPOPT_TS_TSONLY 0 /* timestamps only */ 145#define IPOPT_TS_TSANDADDR 1 /* timestamps and addresses */ 146#define IPOPT_TS_PRESPEC 3 /* specified modules only */ 147 148/* bits for security (not byte swapped) */ 149#define IPOPT_SECUR_UNCLASS 0x0000 150#define IPOPT_SECUR_CONFID 0xf135 151#define IPOPT_SECUR_EFTO 0x789a 152#define IPOPT_SECUR_MMMM 0xbc4d 153#define IPOPT_SECUR_RESTR 0xaf13 154#define IPOPT_SECUR_SECRET 0xd788 155#define IPOPT_SECUR_TOPSECRET 0x6bc5 156 157/* 158 * Internet implementation parameters. 159 */ 160#define MAXTTL 255 /* maximum time to live (seconds) */ 161#define IPDEFTTL 64 /* default ttl, from RFC 1340 */ 162#define IPFRAGTTL 60 /* time to live for frags, slowhz */ 163#define IPTTLDEC 1 /* subtracted when forwarding */ 164 165#define IP_MSS 576 /* default maximum segment size */ 166#endif /* TCPDUMP_IP_H */ 167