tcpdump/ip.h
Guy Harris 53412397f6 Mark various IPv4 and IPv6 headers as unaligned.
This prevents GCC on SPARC from generating code that assumes those
structures are aligned naturally, which they are not guaranteed to be.

Move some #defines from interface.h to tcpdump-stdinc.h to make them
available to code that doesn't include interface.h.

Move the declaration of nextproto6_cksum() to ip6.h, so that only files
that use it get it declared, and thus so that you don't need to define
"struct ip6_hdr" in everything that includes interface.h.  Don't include
ip6.h in tcpdump-stdinc.h.
2010-08-31 10:03:47 -07:00

165 lines
5.8 KiB
C

/* @(#) $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 u_int32_t ip_finddst(const struct ip *);