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Diffstat (limited to 'ip.h')
| -rw-r--r-- | ip.h | 164 |
1 files changed, 164 insertions, 0 deletions
@@ -0,0 +1,164 @@ +/* @(#) $Header: /tcpdump/master/tcpdump/ip.h,v 1.12 2007-09-14 01:29:28 guy Exp $ (LBL) */ +/* + * 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. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 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 + */ + +/* + * Definitions for internet protocol version 4. + * Per RFC 791, September 1981. + */ +#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 { + u_int8_t ip_vhl; /* header length, version */ +#define IP_V(ip) (((ip)->ip_vhl & 0xf0) >> 4) +#define IP_HL(ip) ((ip)->ip_vhl & 0x0f) + u_int8_t ip_tos; /* type of service */ + u_int16_t ip_len; /* total length */ + u_int16_t ip_id; /* identification */ + u_int16_t ip_off; /* fragment offset field */ +#define IP_DF 0x4000 /* dont fragment flag */ +#define IP_MF 0x2000 /* more fragments flag */ +#define IP_OFFMASK 0x1fff /* mask for fragmenting bits */ + u_int8_t ip_ttl; /* time to live */ + u_int8_t ip_p; /* protocol */ + u_int16_t ip_sum; /* checksum */ + struct in_addr ip_src,ip_dst; /* source and dest address */ +} UNALIGNED; + +#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_RFC1393 82 /* traceroute RFC 1393 */ +#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 */ +#define IPOPT_RA 148 /* router-alert, rfc2113 */ + +/* + * 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_int8_t ipt_code; /* IPOPT_TS */ + u_int8_t ipt_len; /* size of structure (variable) */ + u_int8_t ipt_ptr; /* index of current entry */ + u_int8_t ipt_oflwflg; /* flags, overflow counter */ +#define IPTS_OFLW(ip) (((ipt)->ipt_oflwflg & 0xf0) >> 4) +#define IPTS_FLG(ip) ((ipt)->ipt_oflwflg & 0x0f) + union ipt_timestamp { + u_int32_t ipt_time[1]; + struct ipt_ta { + struct in_addr ipt_addr; + u_int32_t ipt_time; + } ipt_ta[1]; + } ipt_timestamp; +} UNALIGNED; + +/* 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 */ + +/* in print-ip.c */ +extern int nextproto4_cksum(const struct ip *, const u_int8_t *, u_int, u_int); |