Update libpcap to 1.1.1.
Changes:
Thu. April 1, 2010. guy@alum.mit.edu.
Summary for 1.1.1 libpcap release
Update CHANGES to reflect more of the changes in 1.1.0.
Fix build on RHEL5.
Fix shared library build on AIX.
Thu. March 11, 2010. ken@netfunctional.ca/guy@alum.mit.edu.
Summary for 1.1.0 libpcap release
Add SocketCAN capture support
Add Myricom SNF API support
Update Endace DAG and ERF support
Add support for shared libraries on Solaris, HP-UX, and AIX
Build, install, and un-install shared libraries by default;
don't build/install shared libraries on platforms we don't support
Fix building from a directory other than the source directory
Fix compiler warnings and builds on some platforms
Update config.guess and config.sub
Support monitor mode on mac80211 devices on Linux
Fix USB memory-mapped capturing on Linux; it requires a new DLT_
value
On Linux, scan /sys/class/net for devices if we have it; scan
it, or /proc/net/dev if we don't have /sys/class/net, even if
we have getifaddrs(), as it'll find interfaces with no
addresses
Add limited support for reading pcap-ng files
Fix BPF driver-loading error handling on AIX
Support getting the full-length interface description on FreeBSD
In the lexical analyzer, free up any addrinfo structure we got back
from getaddrinfo().
Add support for BPF and libdlpi in OpenSolaris (and SXCE)
Hyphenate "link-layer" everywhere
Add /sys/kernel/debug/usb/usbmon to the list of usbmon locations
In pcap_read_linux_mmap(), if there are no frames available, call
poll() even if we're in non-blocking mode, so we pick up
errors, and check for the errors in question.
Note that poll() works on BPF devices is Snow Leopard
If an ENXIO or ENETDOWN is received, it may mean the device has
gone away. Deal with it.
For BPF, raise the default capture buffer size to from 32k to 512k
Support ps_ifdrop on Linux
Added a bunch of #ifdef directives to make wpcap.dll (WinPcap) compile
under cygwin.
Changes to Linux mmapped captures.
Fix bug where create_ring would fail for particular snaplen and
buffer size combinations
Update pcap-config so that it handles libpcap requiring
additional libraries
Add workaround for threadsafeness on Windows
Add missing mapping for DLT_ENC <-> LINKTYPE_ENC
DLT: Add DLT_CAN_SOCKETCAN
DLT: Add Solaris ipnet
Don't check for DLT_IPNET if it's not defined
Add link-layer types for Fibre Channel FC-2
Add link-layer types for Wireless HART
Add link-layer types for AOS
Add link-layer types for DECT
Autoconf fixes (AIX, HP-UX, OSF/1, Tru64 cleanups)
Install headers unconditionally, and include vlan.h/bluetooth.h if
enabled
Autoconf fixes+cleanup
Support enabling/disabling bluetooth (--{en,dis}able-bluetooth)
Support disabling SITA support (--without-sita)
Return -1 on failure to create packet ring (if supported but
creation failed)
Fix handling of 'any' device, so that it can be opened, and no longer
attempt to open it in Monitor mode
Add support for snapshot length for USB Memory-Mapped Interface
Fix configure and build on recent Linux kernels
Fix memory-mapped Linux capture to support pcap_next() and
pcap_next_ex()
Fixes for Linux USB capture
DLT: Add DLT_LINUX_EVDEV
DLT: Add DLT_GSMTAP_UM
DLT: Add DLT_GSMTAP_ABIS
2010-10-28 16:22:13 +00:00
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.\" @(#) $Header: /tcpdump/master/libpcap/pcap-filter.manmisc.in,v 1.1 2008-10-21 07:33:01 guy Exp $ (LBL)
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2009-03-21 20:43:56 +00:00
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.\"
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.\" Copyright (c) 1987, 1988, 1989, 1990, 1991, 1992, 1994, 1995, 1996, 1997
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.\" The Regents of the University of California. All rights reserved.
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.\" All rights reserved.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that: (1) source code distributions
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.\" retain the above copyright notice and this paragraph in its entirety, (2)
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.\" distributions including binary code include the above copyright notice and
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.\" this paragraph in its entirety in the documentation or other materials
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.\" provided with the distribution, and (3) all advertising materials mentioning
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.\" features or use of this software display the following acknowledgement:
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.\" ``This product includes software developed by the University of California,
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.\" Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
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.\" the University nor the names of its contributors may be used to endorse
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.\" or promote products derived from this software without specific prior
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.\" written permission.
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.\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
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.\" WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
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.\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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.\"
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2009-03-21 22:58:08 +00:00
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.TH PCAP-FILTER 7 "6 January 2008"
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2009-03-21 20:43:56 +00:00
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.SH NAME
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pcap-filter \- packet filter syntax
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.br
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.ad
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.SH DESCRIPTION
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.LP
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.B pcap_compile()
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is used to compile a string into a filter program.
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The resulting filter program can then be applied to
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some stream of packets to determine which packets will be supplied to
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.BR pcap_loop() ,
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.BR pcap_dispatch() ,
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.BR pcap_next() ,
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or
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.BR pcap_next_ex() .
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.LP
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The \fIfilter expression\fP consists of one or more
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.IR primitives .
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Primitives usually consist of an
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.I id
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(name or number) preceded by one or more qualifiers.
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There are three
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different kinds of qualifier:
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.IP \fItype\fP
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2013-05-30 06:41:26 +00:00
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.I type
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2009-03-21 20:43:56 +00:00
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qualifiers say what kind of thing the id name or number refers to.
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Possible types are
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.BR host ,
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.B net ,
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.B port
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and
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.BR portrange .
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E.g., `host foo', `net 128.3', `port 20', `portrange 6000-6008'.
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If there is no type
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qualifier,
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.B host
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is assumed.
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.IP \fIdir\fP
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2013-05-30 06:41:26 +00:00
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.I dir
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2009-03-21 20:43:56 +00:00
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qualifiers specify a particular transfer direction to and/or from
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.IR id .
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Possible directions are
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.BR src ,
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.BR dst ,
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.BR "src or dst" ,
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.BR "src and dst" ,
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2012-01-31 17:22:07 +00:00
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.BR ra ,
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.BR ta ,
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2009-03-21 20:43:56 +00:00
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.BR addr1 ,
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.BR addr2 ,
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.BR addr3 ,
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and
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.BR addr4 .
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E.g., `src foo', `dst net 128.3', `src or dst port ftp-data'.
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If
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there is no dir qualifier,
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.B "src or dst"
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is assumed.
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The
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2012-01-31 17:22:07 +00:00
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.BR ra ,
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.BR ta ,
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2009-03-21 20:43:56 +00:00
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.BR addr1 ,
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.BR addr2 ,
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.BR addr3 ,
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and
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.B addr4
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qualifiers are only valid for IEEE 802.11 Wireless LAN link layers.
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For some link layers, such as SLIP and the ``cooked'' Linux capture mode
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used for the ``any'' device and for some other device types, the
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.B inbound
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and
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.B outbound
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qualifiers can be used to specify a desired direction.
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.IP \fIproto\fP
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2013-05-30 06:41:26 +00:00
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.I proto
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2009-03-21 20:43:56 +00:00
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qualifiers restrict the match to a particular protocol.
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Possible
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protos are:
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.BR ether ,
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.BR fddi ,
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.BR tr ,
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.BR wlan ,
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.BR ip ,
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.BR ip6 ,
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.BR arp ,
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.BR rarp ,
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.BR decnet ,
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.B tcp
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and
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.BR udp .
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E.g., `ether src foo', `arp net 128.3', `tcp port 21', `udp portrange
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7000-7009', `wlan addr2 0:2:3:4:5:6'.
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If there is
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no proto qualifier, all protocols consistent with the type are
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assumed.
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E.g., `src foo' means `(ip or arp or rarp) src foo'
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(except the latter is not legal syntax), `net bar' means `(ip or
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arp or rarp) net bar' and `port 53' means `(tcp or udp) port 53'.
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.LP
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[`fddi' is actually an alias for `ether'; the parser treats them
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identically as meaning ``the data link level used on the specified
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network interface.'' FDDI headers contain Ethernet-like source
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and destination addresses, and often contain Ethernet-like packet
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types, so you can filter on these FDDI fields just as with the
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analogous Ethernet fields.
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FDDI headers also contain other fields,
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but you cannot name them explicitly in a filter expression.
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.LP
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Similarly, `tr' and `wlan' are aliases for `ether'; the previous
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paragraph's statements about FDDI headers also apply to Token Ring
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and 802.11 wireless LAN headers. For 802.11 headers, the destination
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address is the DA field and the source address is the SA field; the
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BSSID, RA, and TA fields aren't tested.]
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.LP
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In addition to the above, there are some special `primitive' keywords
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that don't follow the pattern:
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.BR gateway ,
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.BR broadcast ,
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.BR less ,
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.B greater
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and arithmetic expressions.
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All of these are described below.
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.LP
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More complex filter expressions are built up by using the words
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.BR and ,
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.B or
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and
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.B not
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to combine primitives.
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E.g., `host foo and not port ftp and not port ftp-data'.
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To save typing, identical qualifier lists can be omitted.
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E.g.,
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`tcp dst port ftp or ftp-data or domain' is exactly the same as
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`tcp dst port ftp or tcp dst port ftp-data or tcp dst port domain'.
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.LP
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Allowable primitives are:
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.IP "\fBdst host \fIhost\fR"
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True if the IPv4/v6 destination field of the packet is \fIhost\fP,
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which may be either an address or a name.
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.IP "\fBsrc host \fIhost\fR"
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True if the IPv4/v6 source field of the packet is \fIhost\fP.
|
2013-05-30 06:41:26 +00:00
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.IP "\fBhost \fIhost\fP"
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2009-03-21 20:43:56 +00:00
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True if either the IPv4/v6 source or destination of the packet is \fIhost\fP.
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.IP
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|
Any of the above host expressions can be prepended with the keywords,
|
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|
\fBip\fP, \fBarp\fP, \fBrarp\fP, or \fBip6\fP as in:
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.in +.5i
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|
.nf
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\fBip host \fIhost\fR
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.fi
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.in -.5i
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which is equivalent to:
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.in +.5i
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.nf
|
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\fBether proto \fI\\ip\fB and host \fIhost\fR
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.fi
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.in -.5i
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If \fIhost\fR is a name with multiple IP addresses, each address will
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be checked for a match.
|
2013-05-30 06:41:26 +00:00
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.IP "\fBether dst \fIehost\fP"
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2009-03-21 20:43:56 +00:00
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True if the Ethernet destination address is \fIehost\fP.
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\fIEhost\fP
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may be either a name from /etc/ethers or a number (see
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.IR ethers (3N)
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|
for numeric format).
|
2013-05-30 06:41:26 +00:00
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.IP "\fBether src \fIehost\fP"
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2009-03-21 20:43:56 +00:00
|
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True if the Ethernet source address is \fIehost\fP.
|
2013-05-30 06:41:26 +00:00
|
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.IP "\fBether host \fIehost\fP"
|
2009-03-21 20:43:56 +00:00
|
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True if either the Ethernet source or destination address is \fIehost\fP.
|
2013-05-30 06:41:26 +00:00
|
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.IP "\fBgateway\fP \fIhost\fP"
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2009-03-21 20:43:56 +00:00
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True if the packet used \fIhost\fP as a gateway.
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I.e., the Ethernet
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source or destination address was \fIhost\fP but neither the IP source
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nor the IP destination was \fIhost\fP.
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\fIHost\fP must be a name and
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must be found both by the machine's host-name-to-IP-address resolution
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mechanisms (host name file, DNS, NIS, etc.) and by the machine's
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host-name-to-Ethernet-address resolution mechanism (/etc/ethers, etc.).
|
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(An equivalent expression is
|
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.in +.5i
|
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.nf
|
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\fBether host \fIehost \fBand not host \fIhost\fR
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.fi
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.in -.5i
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which can be used with either names or numbers for \fIhost / ehost\fP.)
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This syntax does not work in IPv6-enabled configuration at this moment.
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.IP "\fBdst net \fInet\fR"
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True if the IPv4/v6 destination address of the packet has a network
|
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number of \fInet\fP.
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\fINet\fP may be either a name from the networks database
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(/etc/networks, etc.) or a network number.
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An IPv4 network number can be written as a dotted quad (e.g., 192.168.1.0),
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dotted triple (e.g., 192.168.1), dotted pair (e.g, 172.16), or single
|
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number (e.g., 10); the netmask is 255.255.255.255 for a dotted quad
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(which means that it's really a host match), 255.255.255.0 for a dotted
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triple, 255.255.0.0 for a dotted pair, or 255.0.0.0 for a single number.
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An IPv6 network number must be written out fully; the netmask is
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ff:ff:ff:ff:ff:ff:ff:ff, so IPv6 "network" matches are really always
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host matches, and a network match requires a netmask length.
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.IP "\fBsrc net \fInet\fR"
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True if the IPv4/v6 source address of the packet has a network
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number of \fInet\fP.
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.IP "\fBnet \fInet\fR"
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True if either the IPv4/v6 source or destination address of the packet has a network
|
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number of \fInet\fP.
|
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.IP "\fBnet \fInet\fR \fBmask \fInetmask\fR"
|
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|
True if the IPv4 address matches \fInet\fR with the specific \fInetmask\fR.
|
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|
May be qualified with \fBsrc\fR or \fBdst\fR.
|
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Note that this syntax is not valid for IPv6 \fInet\fR.
|
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.IP "\fBnet \fInet\fR/\fIlen\fR"
|
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True if the IPv4/v6 address matches \fInet\fR with a netmask \fIlen\fR
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bits wide.
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May be qualified with \fBsrc\fR or \fBdst\fR.
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.IP "\fBdst port \fIport\fR"
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True if the packet is ip/tcp, ip/udp, ip6/tcp or ip6/udp and has a
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destination port value of \fIport\fP.
|
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The \fIport\fP can be a number or a name used in /etc/services (see
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.IR tcp (4P)
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and
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.IR udp (4P)).
|
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If a name is used, both the port
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number and protocol are checked.
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If a number or ambiguous name is used,
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only the port number is checked (e.g., \fBdst port 513\fR will print both
|
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tcp/login traffic and udp/who traffic, and \fBport domain\fR will print
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both tcp/domain and udp/domain traffic).
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.IP "\fBsrc port \fIport\fR"
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True if the packet has a source port value of \fIport\fP.
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.IP "\fBport \fIport\fR"
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True if either the source or destination port of the packet is \fIport\fP.
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.IP "\fBdst portrange \fIport1\fB-\fIport2\fR"
|
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True if the packet is ip/tcp, ip/udp, ip6/tcp or ip6/udp and has a
|
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destination port value between \fIport1\fP and \fIport2\fP.
|
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|
.I port1
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and
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.I port2
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are interpreted in the same fashion as the
|
|
|
|
.I port
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|
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|
parameter for
|
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|
.BR port .
|
|
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|
.IP "\fBsrc portrange \fIport1\fB-\fIport2\fR"
|
|
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|
True if the packet has a source port value between \fIport1\fP and
|
|
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|
\fIport2\fP.
|
|
|
|
.IP "\fBportrange \fIport1\fB-\fIport2\fR"
|
|
|
|
True if either the source or destination port of the packet is between
|
|
|
|
\fIport1\fP and \fIport2\fP.
|
|
|
|
.IP
|
|
|
|
Any of the above port or port range expressions can be prepended with
|
|
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|
the keywords, \fBtcp\fP or \fBudp\fP, as in:
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBtcp src port \fIport\fR
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
which matches only tcp packets whose source port is \fIport\fP.
|
|
|
|
.IP "\fBless \fIlength\fR"
|
|
|
|
True if the packet has a length less than or equal to \fIlength\fP.
|
|
|
|
This is equivalent to:
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBlen <= \fIlength\fP.
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
.IP "\fBgreater \fIlength\fR"
|
|
|
|
True if the packet has a length greater than or equal to \fIlength\fP.
|
|
|
|
This is equivalent to:
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBlen >= \fIlength\fP.
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
.IP "\fBip proto \fIprotocol\fR"
|
|
|
|
True if the packet is an IPv4 packet (see
|
|
|
|
.IR ip (4P))
|
|
|
|
of protocol type \fIprotocol\fP.
|
|
|
|
\fIProtocol\fP can be a number or one of the names
|
|
|
|
\fBicmp\fP, \fBicmp6\fP, \fBigmp\fP, \fBigrp\fP, \fBpim\fP, \fBah\fP,
|
|
|
|
\fBesp\fP, \fBvrrp\fP, \fBudp\fP, or \fBtcp\fP.
|
|
|
|
Note that the identifiers \fBtcp\fP, \fBudp\fP, and \fBicmp\fP are also
|
|
|
|
keywords and must be escaped via backslash (\\), which is \\\\ in the C-shell.
|
|
|
|
Note that this primitive does not chase the protocol header chain.
|
|
|
|
.IP "\fBip6 proto \fIprotocol\fR"
|
|
|
|
True if the packet is an IPv6 packet of protocol type \fIprotocol\fP.
|
|
|
|
Note that this primitive does not chase the protocol header chain.
|
2013-05-30 06:41:26 +00:00
|
|
|
.IP "\fBproto \fIprotocol\fR"
|
|
|
|
True if the packet is an IPv4 or IPv6 packet of protocol type
|
|
|
|
\fIprotocol\fP. Note that this primitive does not chase the protocol
|
|
|
|
header chain.
|
|
|
|
.IP "\fBtcp\fR, \fBudp\fR, \fBicmp\fR"
|
|
|
|
Abbreviations for:
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBproto \fIp\fR\fB
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
where \fIp\fR is one of the above protocols.
|
2009-03-21 20:43:56 +00:00
|
|
|
.IP "\fBip6 protochain \fIprotocol\fR"
|
|
|
|
True if the packet is IPv6 packet,
|
|
|
|
and contains protocol header with type \fIprotocol\fR
|
|
|
|
in its protocol header chain.
|
|
|
|
For example,
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBip6 protochain 6\fR
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
matches any IPv6 packet with TCP protocol header in the protocol header chain.
|
|
|
|
The packet may contain, for example,
|
|
|
|
authentication header, routing header, or hop-by-hop option header,
|
|
|
|
between IPv6 header and TCP header.
|
|
|
|
The BPF code emitted by this primitive is complex and
|
|
|
|
cannot be optimized by the BPF optimizer code, so this can be somewhat
|
|
|
|
slow.
|
|
|
|
.IP "\fBip protochain \fIprotocol\fR"
|
|
|
|
Equivalent to \fBip6 protochain \fIprotocol\fR, but this is for IPv4.
|
2013-05-30 06:41:26 +00:00
|
|
|
.IP "\fBprotochain \fIprotocol\fR"
|
|
|
|
True if the packet is an IPv4 or IPv6 packet of protocol type
|
|
|
|
\fIprotocol\fP. Note that this primitive chases the protocol
|
|
|
|
header chain.
|
2009-03-21 20:43:56 +00:00
|
|
|
.IP "\fBether broadcast\fR"
|
|
|
|
True if the packet is an Ethernet broadcast packet.
|
|
|
|
The \fIether\fP
|
|
|
|
keyword is optional.
|
|
|
|
.IP "\fBip broadcast\fR"
|
|
|
|
True if the packet is an IPv4 broadcast packet.
|
|
|
|
It checks for both the all-zeroes and all-ones broadcast conventions,
|
|
|
|
and looks up the subnet mask on the interface on which the capture is
|
|
|
|
being done.
|
|
|
|
.IP
|
|
|
|
If the subnet mask of the interface on which the capture is being done
|
|
|
|
is not available, either because the interface on which capture is being
|
|
|
|
done has no netmask or because the capture is being done on the Linux
|
|
|
|
"any" interface, which can capture on more than one interface, this
|
|
|
|
check will not work correctly.
|
|
|
|
.IP "\fBether multicast\fR"
|
|
|
|
True if the packet is an Ethernet multicast packet.
|
|
|
|
The \fBether\fP
|
|
|
|
keyword is optional.
|
|
|
|
This is shorthand for `\fBether[0] & 1 != 0\fP'.
|
|
|
|
.IP "\fBip multicast\fR"
|
|
|
|
True if the packet is an IPv4 multicast packet.
|
|
|
|
.IP "\fBip6 multicast\fR"
|
|
|
|
True if the packet is an IPv6 multicast packet.
|
|
|
|
.IP "\fBether proto \fIprotocol\fR"
|
|
|
|
True if the packet is of ether type \fIprotocol\fR.
|
|
|
|
\fIProtocol\fP can be a number or one of the names
|
|
|
|
\fBip\fP, \fBip6\fP, \fBarp\fP, \fBrarp\fP, \fBatalk\fP, \fBaarp\fP,
|
|
|
|
\fBdecnet\fP, \fBsca\fP, \fBlat\fP, \fBmopdl\fP, \fBmoprc\fP,
|
|
|
|
\fBiso\fP, \fBstp\fP, \fBipx\fP, or \fBnetbeui\fP.
|
|
|
|
Note these identifiers are also keywords
|
|
|
|
and must be escaped via backslash (\\).
|
|
|
|
.IP
|
|
|
|
[In the case of FDDI (e.g., `\fBfddi protocol arp\fR'), Token Ring
|
|
|
|
(e.g., `\fBtr protocol arp\fR'), and IEEE 802.11 wireless LANS (e.g.,
|
|
|
|
`\fBwlan protocol arp\fR'), for most of those protocols, the
|
|
|
|
protocol identification comes from the 802.2 Logical Link Control (LLC)
|
|
|
|
header, which is usually layered on top of the FDDI, Token Ring, or
|
|
|
|
802.11 header.
|
|
|
|
.IP
|
|
|
|
When filtering for most protocol identifiers on FDDI, Token Ring, or
|
|
|
|
802.11, the filter checks only the protocol ID field of an LLC header
|
|
|
|
in so-called SNAP format with an Organizational Unit Identifier (OUI) of
|
|
|
|
0x000000, for encapsulated Ethernet; it doesn't check whether the packet
|
|
|
|
is in SNAP format with an OUI of 0x000000.
|
|
|
|
The exceptions are:
|
|
|
|
.RS
|
|
|
|
.TP
|
|
|
|
\fBiso\fP
|
|
|
|
the filter checks the DSAP (Destination Service Access Point) and
|
|
|
|
SSAP (Source Service Access Point) fields of the LLC header;
|
|
|
|
.TP
|
|
|
|
\fBstp\fP and \fBnetbeui\fP
|
|
|
|
the filter checks the DSAP of the LLC header;
|
|
|
|
.TP
|
|
|
|
\fBatalk\fP
|
|
|
|
the filter checks for a SNAP-format packet with an OUI of 0x080007
|
|
|
|
and the AppleTalk etype.
|
|
|
|
.RE
|
|
|
|
.IP
|
|
|
|
In the case of Ethernet, the filter checks the Ethernet type field
|
|
|
|
for most of those protocols. The exceptions are:
|
|
|
|
.RS
|
|
|
|
.TP
|
|
|
|
\fBiso\fP, \fBstp\fP, and \fBnetbeui\fP
|
|
|
|
the filter checks for an 802.3 frame and then checks the LLC header as
|
|
|
|
it does for FDDI, Token Ring, and 802.11;
|
|
|
|
.TP
|
|
|
|
\fBatalk\fP
|
|
|
|
the filter checks both for the AppleTalk etype in an Ethernet frame and
|
|
|
|
for a SNAP-format packet as it does for FDDI, Token Ring, and 802.11;
|
|
|
|
.TP
|
|
|
|
\fBaarp\fP
|
|
|
|
the filter checks for the AppleTalk ARP etype in either an Ethernet
|
|
|
|
frame or an 802.2 SNAP frame with an OUI of 0x000000;
|
|
|
|
.TP
|
|
|
|
\fBipx\fP
|
|
|
|
the filter checks for the IPX etype in an Ethernet frame, the IPX
|
|
|
|
DSAP in the LLC header, the 802.3-with-no-LLC-header encapsulation of
|
|
|
|
IPX, and the IPX etype in a SNAP frame.
|
|
|
|
.RE
|
2013-05-30 06:41:26 +00:00
|
|
|
.IP "\fBip\fR, \fBip6\fR, \fBarp\fR, \fBrarp\fR, \fBatalk\fR, \fBaarp\fR, \fBdecnet\fR, \fBiso\fR, \fBstp\fR, \fBipx\fR, \fBnetbeui\fP"
|
|
|
|
Abbreviations for:
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBether proto \fIp\fR
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
where \fIp\fR is one of the above protocols.
|
|
|
|
.IP "\fBlat\fR, \fBmoprc\fR, \fBmopdl\fR"
|
|
|
|
Abbreviations for:
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBether proto \fIp\fR
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
where \fIp\fR is one of the above protocols.
|
|
|
|
Note that not all applications using
|
|
|
|
.BR pcap (3PCAP)
|
|
|
|
currently know how to parse these protocols.
|
2009-03-21 20:43:56 +00:00
|
|
|
.IP "\fBdecnet src \fIhost\fR"
|
|
|
|
True if the DECNET source address is
|
|
|
|
.IR host ,
|
|
|
|
which may be an address of the form ``10.123'', or a DECNET host
|
|
|
|
name.
|
|
|
|
[DECNET host name support is only available on ULTRIX systems
|
|
|
|
that are configured to run DECNET.]
|
|
|
|
.IP "\fBdecnet dst \fIhost\fR"
|
|
|
|
True if the DECNET destination address is
|
|
|
|
.IR host .
|
|
|
|
.IP "\fBdecnet host \fIhost\fR"
|
|
|
|
True if either the DECNET source or destination address is
|
|
|
|
.IR host .
|
|
|
|
.IP "\fBifname \fIinterface\fR"
|
|
|
|
True if the packet was logged as coming from the specified interface (applies
|
|
|
|
only to packets logged by OpenBSD's or FreeBSD's
|
|
|
|
.BR pf (4)).
|
|
|
|
.IP "\fBon \fIinterface\fR"
|
|
|
|
Synonymous with the
|
|
|
|
.B ifname
|
|
|
|
modifier.
|
|
|
|
.IP "\fBrnr \fInum\fR"
|
|
|
|
True if the packet was logged as matching the specified PF rule number
|
|
|
|
(applies only to packets logged by OpenBSD's or FreeBSD's
|
|
|
|
.BR pf (4)).
|
|
|
|
.IP "\fBrulenum \fInum\fR"
|
|
|
|
Synonymous with the
|
|
|
|
.B rnr
|
|
|
|
modifier.
|
|
|
|
.IP "\fBreason \fIcode\fR"
|
|
|
|
True if the packet was logged with the specified PF reason code. The known
|
|
|
|
codes are:
|
|
|
|
.BR match ,
|
|
|
|
.BR bad-offset ,
|
|
|
|
.BR fragment ,
|
|
|
|
.BR short ,
|
|
|
|
.BR normalize ,
|
|
|
|
and
|
|
|
|
.B memory
|
|
|
|
(applies only to packets logged by OpenBSD's or FreeBSD's
|
|
|
|
.BR pf (4)).
|
|
|
|
.IP "\fBrset \fIname\fR"
|
|
|
|
True if the packet was logged as matching the specified PF ruleset
|
|
|
|
name of an anchored ruleset (applies only to packets logged by OpenBSD's
|
|
|
|
or FreeBSD's
|
|
|
|
.BR pf (4)).
|
|
|
|
.IP "\fBruleset \fIname\fR"
|
|
|
|
Synonomous with the
|
|
|
|
.B rset
|
|
|
|
modifier.
|
|
|
|
.IP "\fBsrnr \fInum\fR"
|
|
|
|
True if the packet was logged as matching the specified PF rule number
|
|
|
|
of an anchored ruleset (applies only to packets logged by OpenBSD's or
|
|
|
|
FreeBSD's
|
|
|
|
.BR pf (4)).
|
|
|
|
.IP "\fBsubrulenum \fInum\fR"
|
|
|
|
Synonomous with the
|
|
|
|
.B srnr
|
|
|
|
modifier.
|
|
|
|
.IP "\fBaction \fIact\fR"
|
|
|
|
True if PF took the specified action when the packet was logged. Known actions
|
|
|
|
are:
|
|
|
|
.B pass
|
|
|
|
and
|
|
|
|
.B block
|
|
|
|
and, with later versions of
|
|
|
|
.BR pf (4)),
|
|
|
|
.BR nat ,
|
|
|
|
.BR rdr ,
|
|
|
|
.B binat
|
|
|
|
and
|
|
|
|
.B scrub
|
|
|
|
(applies only to packets logged by OpenBSD's or FreeBSD's
|
|
|
|
.BR pf (4)).
|
2012-01-31 17:22:07 +00:00
|
|
|
.IP "\fBwlan ra \fIehost\fR"
|
|
|
|
True if the IEEE 802.11 RA is
|
|
|
|
.IR ehost .
|
|
|
|
The RA field is used in all frames except for management frames.
|
|
|
|
.IP "\fBwlan ta \fIehost\fR"
|
|
|
|
True if the IEEE 802.11 TA is
|
|
|
|
.IR ehost .
|
|
|
|
The TA field is used in all frames except for management frames and
|
|
|
|
CTS (Clear To Send) and ACK (Acknowledgment) control frames.
|
2009-03-21 20:43:56 +00:00
|
|
|
.IP "\fBwlan addr1 \fIehost\fR"
|
|
|
|
True if the first IEEE 802.11 address is
|
|
|
|
.IR ehost .
|
|
|
|
.IP "\fBwlan addr2 \fIehost\fR"
|
|
|
|
True if the second IEEE 802.11 address, if present, is
|
|
|
|
.IR ehost .
|
|
|
|
The second address field is used in all frames except for CTS (Clear To
|
|
|
|
Send) and ACK (Acknowledgment) control frames.
|
|
|
|
.IP "\fBwlan addr3 \fIehost\fR"
|
|
|
|
True if the third IEEE 802.11 address, if present, is
|
|
|
|
.IR ehost .
|
|
|
|
The third address field is used in management and data frames, but not
|
|
|
|
in control frames.
|
|
|
|
.IP "\fBwlan addr4 \fIehost\fR"
|
|
|
|
True if the fourth IEEE 802.11 address, if present, is
|
|
|
|
.IR ehost .
|
|
|
|
The fourth address field is only used for
|
|
|
|
WDS (Wireless Distribution System) frames.
|
|
|
|
.IP "\fBtype \fIwlan_type\fR"
|
|
|
|
True if the IEEE 802.11 frame type matches the specified \fIwlan_type\fR.
|
|
|
|
Valid \fIwlan_type\fRs are:
|
|
|
|
\fBmgt\fP,
|
|
|
|
\fBctl\fP
|
|
|
|
and \fBdata\fP.
|
|
|
|
.IP "\fBtype \fIwlan_type \fBsubtype \fIwlan_subtype\fR"
|
|
|
|
True if the IEEE 802.11 frame type matches the specified \fIwlan_type\fR
|
|
|
|
and frame subtype matches the specified \fIwlan_subtype\fR.
|
|
|
|
.IP
|
|
|
|
If the specified \fIwlan_type\fR is \fBmgt\fP,
|
|
|
|
then valid \fIwlan_subtype\fRs are:
|
|
|
|
\fBassoc-req\fP,
|
|
|
|
\fBassoc-resp\fP,
|
|
|
|
\fBreassoc-req\fP,
|
|
|
|
\fBreassoc-resp\fP,
|
|
|
|
\fBprobe-req\fP,
|
|
|
|
\fBprobe-resp\fP,
|
|
|
|
\fBbeacon\fP,
|
|
|
|
\fBatim\fP,
|
|
|
|
\fBdisassoc\fP,
|
|
|
|
\fBauth\fP and
|
|
|
|
\fBdeauth\fP.
|
|
|
|
.IP
|
|
|
|
If the specified \fIwlan_type\fR is \fBctl\fP,
|
|
|
|
then valid \fIwlan_subtype\fRs are:
|
|
|
|
\fBps-poll\fP,
|
|
|
|
\fBrts\fP,
|
|
|
|
\fBcts\fP,
|
|
|
|
\fBack\fP,
|
|
|
|
\fBcf-end\fP and
|
|
|
|
\fBcf-end-ack\fP.
|
|
|
|
.IP
|
|
|
|
If the specified \fIwlan_type\fR is \fBdata\fP,
|
|
|
|
then valid \fIwlan_subtype\fRs are:
|
|
|
|
\fBdata\fP,
|
|
|
|
\fBdata-cf-ack\fP,
|
|
|
|
\fBdata-cf-poll\fP,
|
|
|
|
\fBdata-cf-ack-poll\fP,
|
|
|
|
\fBnull\fP,
|
|
|
|
\fBcf-ack\fP,
|
|
|
|
\fBcf-poll\fP,
|
|
|
|
\fBcf-ack-poll\fP,
|
|
|
|
\fBqos-data\fP,
|
|
|
|
\fBqos-data-cf-ack\fP,
|
|
|
|
\fBqos-data-cf-poll\fP,
|
|
|
|
\fBqos-data-cf-ack-poll\fP,
|
|
|
|
\fBqos\fP,
|
|
|
|
\fBqos-cf-poll\fP and
|
|
|
|
\fBqos-cf-ack-poll\fP.
|
|
|
|
.IP "\fBsubtype \fIwlan_subtype\fR"
|
|
|
|
True if the IEEE 802.11 frame subtype matches the specified \fIwlan_subtype\fR
|
|
|
|
and frame has the type to which the specified \fIwlan_subtype\fR belongs.
|
|
|
|
.IP "\fBdir \fIdir\fR"
|
|
|
|
True if the IEEE 802.11 frame direction matches the specified
|
|
|
|
.IR dir .
|
|
|
|
Valid directions are:
|
|
|
|
.BR nods ,
|
|
|
|
.BR tods ,
|
|
|
|
.BR fromds ,
|
|
|
|
.BR dstods ,
|
|
|
|
or a numeric value.
|
|
|
|
.IP "\fBvlan \fI[vlan_id]\fR"
|
|
|
|
True if the packet is an IEEE 802.1Q VLAN packet.
|
|
|
|
If \fI[vlan_id]\fR is specified, only true if the packet has the specified
|
|
|
|
\fIvlan_id\fR.
|
|
|
|
Note that the first \fBvlan\fR keyword encountered in \fIexpression\fR
|
|
|
|
changes the decoding offsets for the remainder of \fIexpression\fR on
|
|
|
|
the assumption that the packet is a VLAN packet. The \fBvlan
|
|
|
|
\fI[vlan_id]\fR expression may be used more than once, to filter on VLAN
|
|
|
|
hierarchies. Each use of that expression increments the filter offsets
|
|
|
|
by 4.
|
|
|
|
.IP
|
|
|
|
For example:
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBvlan 100 && vlan 200\fR
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
filters on VLAN 200 encapsulated within VLAN 100, and
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBvlan && vlan 300 && ip\fR
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
filters IPv4 protocols encapsulated in VLAN 300 encapsulated within any
|
|
|
|
higher order VLAN.
|
|
|
|
.IP "\fBmpls \fI[label_num]\fR"
|
|
|
|
True if the packet is an MPLS packet.
|
|
|
|
If \fI[label_num]\fR is specified, only true is the packet has the specified
|
|
|
|
\fIlabel_num\fR.
|
|
|
|
Note that the first \fBmpls\fR keyword encountered in \fIexpression\fR
|
|
|
|
changes the decoding offsets for the remainder of \fIexpression\fR on
|
|
|
|
the assumption that the packet is a MPLS-encapsulated IP packet. The
|
|
|
|
\fBmpls \fI[label_num]\fR expression may be used more than once, to
|
|
|
|
filter on MPLS hierarchies. Each use of that expression increments the
|
|
|
|
filter offsets by 4.
|
|
|
|
.IP
|
|
|
|
For example:
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBmpls 100000 && mpls 1024\fR
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
filters packets with an outer label of 100000 and an inner label of
|
|
|
|
1024, and
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBmpls && mpls 1024 && host 192.9.200.1\fR
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
filters packets to or from 192.9.200.1 with an inner label of 1024 and
|
|
|
|
any outer label.
|
|
|
|
.IP \fBpppoed\fP
|
|
|
|
True if the packet is a PPP-over-Ethernet Discovery packet (Ethernet
|
|
|
|
type 0x8863).
|
|
|
|
.IP \fBpppoes\fP
|
|
|
|
True if the packet is a PPP-over-Ethernet Session packet (Ethernet
|
|
|
|
type 0x8864).
|
|
|
|
Note that the first \fBpppoes\fR keyword encountered in \fIexpression\fR
|
|
|
|
changes the decoding offsets for the remainder of \fIexpression\fR on
|
|
|
|
the assumption that the packet is a PPPoE session packet.
|
|
|
|
.IP
|
|
|
|
For example:
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBpppoes && ip\fR
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
filters IPv4 protocols encapsulated in PPPoE.
|
|
|
|
.IP "\fBiso proto \fIprotocol\fR"
|
|
|
|
True if the packet is an OSI packet of protocol type \fIprotocol\fP.
|
|
|
|
\fIProtocol\fP can be a number or one of the names
|
|
|
|
\fBclnp\fP, \fBesis\fP, or \fBisis\fP.
|
|
|
|
.IP "\fBclnp\fR, \fBesis\fR, \fBisis\fR"
|
|
|
|
Abbreviations for:
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBiso proto \fIp\fR
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
where \fIp\fR is one of the above protocols.
|
|
|
|
.IP "\fBl1\fR, \fBl2\fR, \fBiih\fR, \fBlsp\fR, \fBsnp\fR, \fBcsnp\fR, \fBpsnp\fR"
|
|
|
|
Abbreviations for IS-IS PDU types.
|
2013-05-30 06:41:26 +00:00
|
|
|
.IP "\fBvpi\fP \fIn\fR"
|
2009-03-21 20:43:56 +00:00
|
|
|
True if the packet is an ATM packet, for SunATM on Solaris, with a
|
|
|
|
virtual path identifier of
|
|
|
|
.IR n .
|
2013-05-30 06:41:26 +00:00
|
|
|
.IP "\fBvci\fP \fIn\fR"
|
2009-03-21 20:43:56 +00:00
|
|
|
True if the packet is an ATM packet, for SunATM on Solaris, with a
|
|
|
|
virtual channel identifier of
|
|
|
|
.IR n .
|
|
|
|
.IP \fBlane\fP
|
|
|
|
True if the packet is an ATM packet, for SunATM on Solaris, and is
|
|
|
|
an ATM LANE packet.
|
|
|
|
Note that the first \fBlane\fR keyword encountered in \fIexpression\fR
|
|
|
|
changes the tests done in the remainder of \fIexpression\fR
|
|
|
|
on the assumption that the packet is either a LANE emulated Ethernet
|
|
|
|
packet or a LANE LE Control packet. If \fBlane\fR isn't specified, the
|
|
|
|
tests are done under the assumption that the packet is an
|
|
|
|
LLC-encapsulated packet.
|
|
|
|
.IP \fBllc\fP
|
|
|
|
True if the packet is an ATM packet, for SunATM on Solaris, and is
|
|
|
|
an LLC-encapsulated packet.
|
|
|
|
.IP \fBoamf4s\fP
|
|
|
|
True if the packet is an ATM packet, for SunATM on Solaris, and is
|
|
|
|
a segment OAM F4 flow cell (VPI=0 & VCI=3).
|
|
|
|
.IP \fBoamf4e\fP
|
|
|
|
True if the packet is an ATM packet, for SunATM on Solaris, and is
|
|
|
|
an end-to-end OAM F4 flow cell (VPI=0 & VCI=4).
|
|
|
|
.IP \fBoamf4\fP
|
|
|
|
True if the packet is an ATM packet, for SunATM on Solaris, and is
|
|
|
|
a segment or end-to-end OAM F4 flow cell (VPI=0 & (VCI=3 | VCI=4)).
|
|
|
|
.IP \fBoam\fP
|
|
|
|
True if the packet is an ATM packet, for SunATM on Solaris, and is
|
|
|
|
a segment or end-to-end OAM F4 flow cell (VPI=0 & (VCI=3 | VCI=4)).
|
|
|
|
.IP \fBmetac\fP
|
|
|
|
True if the packet is an ATM packet, for SunATM on Solaris, and is
|
|
|
|
on a meta signaling circuit (VPI=0 & VCI=1).
|
|
|
|
.IP \fBbcc\fP
|
|
|
|
True if the packet is an ATM packet, for SunATM on Solaris, and is
|
|
|
|
on a broadcast signaling circuit (VPI=0 & VCI=2).
|
|
|
|
.IP \fBsc\fP
|
|
|
|
True if the packet is an ATM packet, for SunATM on Solaris, and is
|
|
|
|
on a signaling circuit (VPI=0 & VCI=5).
|
|
|
|
.IP \fBilmic\fP
|
|
|
|
True if the packet is an ATM packet, for SunATM on Solaris, and is
|
|
|
|
on an ILMI circuit (VPI=0 & VCI=16).
|
|
|
|
.IP \fBconnectmsg\fP
|
|
|
|
True if the packet is an ATM packet, for SunATM on Solaris, and is
|
|
|
|
on a signaling circuit and is a Q.2931 Setup, Call Proceeding, Connect,
|
|
|
|
Connect Ack, Release, or Release Done message.
|
|
|
|
.IP \fBmetaconnect\fP
|
|
|
|
True if the packet is an ATM packet, for SunATM on Solaris, and is
|
|
|
|
on a meta signaling circuit and is a Q.2931 Setup, Call Proceeding, Connect,
|
|
|
|
Release, or Release Done message.
|
|
|
|
.IP "\fIexpr relop expr\fR"
|
|
|
|
True if the relation holds, where \fIrelop\fR is one of >, <, >=, <=, =,
|
|
|
|
!=, and \fIexpr\fR is an arithmetic expression composed of integer
|
|
|
|
constants (expressed in standard C syntax), the normal binary operators
|
|
|
|
[+, -, *, /, &, |, <<, >>], a length operator, and special packet data
|
|
|
|
accessors. Note that all comparisons are unsigned, so that, for example,
|
|
|
|
0x80000000 and 0xffffffff are > 0.
|
|
|
|
To access
|
|
|
|
data inside the packet, use the following syntax:
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fIproto\fB [ \fIexpr\fB : \fIsize\fB ]\fR
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
\fIProto\fR is one of \fBether, fddi, tr, wlan, ppp, slip, link,
|
|
|
|
ip, arp, rarp, tcp, udp, icmp, ip6\fR or \fBradio\fR, and
|
|
|
|
indicates the protocol layer for the index operation.
|
|
|
|
(\fBether, fddi, wlan, tr, ppp, slip\fR and \fBlink\fR all refer to the
|
|
|
|
link layer. \fBradio\fR refers to the "radio header" added to some
|
|
|
|
802.11 captures.)
|
|
|
|
Note that \fItcp, udp\fR and other upper-layer protocol types only
|
|
|
|
apply to IPv4, not IPv6 (this will be fixed in the future).
|
|
|
|
The byte offset, relative to the indicated protocol layer, is
|
|
|
|
given by \fIexpr\fR.
|
|
|
|
\fISize\fR is optional and indicates the number of bytes in the
|
|
|
|
field of interest; it can be either one, two, or four, and defaults to one.
|
|
|
|
The length operator, indicated by the keyword \fBlen\fP, gives the
|
|
|
|
length of the packet.
|
|
|
|
|
|
|
|
For example, `\fBether[0] & 1 != 0\fP' catches all multicast traffic.
|
|
|
|
The expression `\fBip[0] & 0xf != 5\fP'
|
|
|
|
catches all IPv4 packets with options.
|
|
|
|
The expression
|
|
|
|
`\fBip[6:2] & 0x1fff = 0\fP'
|
|
|
|
catches only unfragmented IPv4 datagrams and frag zero of fragmented
|
|
|
|
IPv4 datagrams.
|
|
|
|
This check is implicitly applied to the \fBtcp\fP and \fBudp\fP
|
|
|
|
index operations.
|
|
|
|
For instance, \fBtcp[0]\fP always means the first
|
|
|
|
byte of the TCP \fIheader\fP, and never means the first byte of an
|
|
|
|
intervening fragment.
|
|
|
|
|
|
|
|
Some offsets and field values may be expressed as names rather than
|
|
|
|
as numeric values.
|
|
|
|
The following protocol header field offsets are
|
|
|
|
available: \fBicmptype\fP (ICMP type field), \fBicmpcode\fP (ICMP
|
|
|
|
code field), and \fBtcpflags\fP (TCP flags field).
|
|
|
|
|
|
|
|
The following ICMP type field values are available: \fBicmp-echoreply\fP,
|
|
|
|
\fBicmp-unreach\fP, \fBicmp-sourcequench\fP, \fBicmp-redirect\fP,
|
|
|
|
\fBicmp-echo\fP, \fBicmp-routeradvert\fP, \fBicmp-routersolicit\fP,
|
|
|
|
\fBicmp-timxceed\fP, \fBicmp-paramprob\fP, \fBicmp-tstamp\fP,
|
|
|
|
\fBicmp-tstampreply\fP, \fBicmp-ireq\fP, \fBicmp-ireqreply\fP,
|
|
|
|
\fBicmp-maskreq\fP, \fBicmp-maskreply\fP.
|
|
|
|
|
|
|
|
The following TCP flags field values are available: \fBtcp-fin\fP,
|
|
|
|
\fBtcp-syn\fP, \fBtcp-rst\fP, \fBtcp-push\fP,
|
|
|
|
\fBtcp-ack\fP, \fBtcp-urg\fP.
|
|
|
|
.LP
|
|
|
|
Primitives may be combined using:
|
|
|
|
.IP
|
|
|
|
A parenthesized group of primitives and operators
|
|
|
|
(parentheses are special to the Shell and must be escaped).
|
|
|
|
.IP
|
|
|
|
Negation (`\fB!\fP' or `\fBnot\fP').
|
|
|
|
.IP
|
|
|
|
Concatenation (`\fB&&\fP' or `\fBand\fP').
|
|
|
|
.IP
|
|
|
|
Alternation (`\fB||\fP' or `\fBor\fP').
|
|
|
|
.LP
|
|
|
|
Negation has highest precedence.
|
|
|
|
Alternation and concatenation have equal precedence and associate
|
|
|
|
left to right.
|
|
|
|
Note that explicit \fBand\fR tokens, not juxtaposition,
|
|
|
|
are now required for concatenation.
|
|
|
|
.LP
|
|
|
|
If an identifier is given without a keyword, the most recent keyword
|
|
|
|
is assumed.
|
|
|
|
For example,
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBnot host vs and ace\fR
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
is short for
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBnot host vs and host ace\fR
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
which should not be confused with
|
|
|
|
.in +.5i
|
|
|
|
.nf
|
|
|
|
\fBnot ( host vs or ace )\fR
|
|
|
|
.fi
|
|
|
|
.in -.5i
|
|
|
|
.SH EXAMPLES
|
|
|
|
.LP
|
|
|
|
To select all packets arriving at or departing from \fIsundown\fP:
|
|
|
|
.RS
|
|
|
|
.nf
|
|
|
|
\fBhost sundown\fP
|
|
|
|
.fi
|
|
|
|
.RE
|
|
|
|
.LP
|
|
|
|
To select traffic between \fIhelios\fR and either \fIhot\fR or \fIace\fR:
|
|
|
|
.RS
|
|
|
|
.nf
|
|
|
|
\fBhost helios and \\( hot or ace \\)\fP
|
|
|
|
.fi
|
|
|
|
.RE
|
|
|
|
.LP
|
|
|
|
To select all IP packets between \fIace\fR and any host except \fIhelios\fR:
|
|
|
|
.RS
|
|
|
|
.nf
|
|
|
|
\fBip host ace and not helios\fP
|
|
|
|
.fi
|
|
|
|
.RE
|
|
|
|
.LP
|
|
|
|
To select all traffic between local hosts and hosts at Berkeley:
|
|
|
|
.RS
|
|
|
|
.nf
|
|
|
|
.B
|
|
|
|
net ucb-ether
|
|
|
|
.fi
|
|
|
|
.RE
|
|
|
|
.LP
|
|
|
|
To select all ftp traffic through internet gateway \fIsnup\fP:
|
|
|
|
.RS
|
|
|
|
.nf
|
|
|
|
.B
|
|
|
|
gateway snup and (port ftp or ftp-data)
|
|
|
|
.fi
|
|
|
|
.RE
|
|
|
|
.LP
|
|
|
|
To select traffic neither sourced from nor destined for local hosts
|
|
|
|
(if you gateway to one other net, this stuff should never make it
|
|
|
|
onto your local net).
|
|
|
|
.RS
|
|
|
|
.nf
|
|
|
|
.B
|
|
|
|
ip and not net \fIlocalnet\fP
|
|
|
|
.fi
|
|
|
|
.RE
|
|
|
|
.LP
|
|
|
|
To select the start and end packets (the SYN and FIN packets) of each
|
|
|
|
TCP conversation that involves a non-local host.
|
|
|
|
.RS
|
|
|
|
.nf
|
|
|
|
.B
|
|
|
|
tcp[tcpflags] & (tcp-syn|tcp-fin) != 0 and not src and dst net \fIlocalnet\fP
|
|
|
|
.fi
|
|
|
|
.RE
|
|
|
|
.LP
|
|
|
|
To select all IPv4 HTTP packets to and from port 80, i.e. print only
|
|
|
|
packets that contain data, not, for example, SYN and FIN packets and
|
|
|
|
ACK-only packets. (IPv6 is left as an exercise for the reader.)
|
|
|
|
.RS
|
|
|
|
.nf
|
|
|
|
.B
|
|
|
|
tcp port 80 and (((ip[2:2] - ((ip[0]&0xf)<<2)) - ((tcp[12]&0xf0)>>2)) != 0)
|
|
|
|
.fi
|
|
|
|
.RE
|
|
|
|
.LP
|
|
|
|
To select IP packets longer than 576 bytes sent through gateway \fIsnup\fP:
|
|
|
|
.RS
|
|
|
|
.nf
|
|
|
|
.B
|
|
|
|
gateway snup and ip[2:2] > 576
|
|
|
|
.fi
|
|
|
|
.RE
|
|
|
|
.LP
|
|
|
|
To select IP broadcast or multicast packets that were
|
|
|
|
.I not
|
|
|
|
sent via Ethernet broadcast or multicast:
|
|
|
|
.RS
|
|
|
|
.nf
|
|
|
|
.B
|
|
|
|
ether[0] & 1 = 0 and ip[16] >= 224
|
|
|
|
.fi
|
|
|
|
.RE
|
|
|
|
.LP
|
|
|
|
To select all ICMP packets that are not echo requests/replies (i.e., not
|
|
|
|
ping packets):
|
|
|
|
.RS
|
|
|
|
.nf
|
|
|
|
.B
|
|
|
|
icmp[icmptype] != icmp-echo and icmp[icmptype] != icmp-echoreply
|
|
|
|
.fi
|
|
|
|
.RE
|
|
|
|
.SH "SEE ALSO"
|
|
|
|
pcap(3PCAP)
|
|
|
|
.SH BUGS
|
|
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Please send problems, bugs, questions, desirable enhancements, etc. to:
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.LP
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.RS
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tcpdump-workers@lists.tcpdump.org
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.RE
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.LP
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Filter expressions on fields other than those in Token Ring headers will
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not correctly handle source-routed Token Ring packets.
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.LP
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Filter expressions on fields other than those in 802.11 headers will not
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correctly handle 802.11 data packets with both To DS and From DS set.
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.LP
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.BR "ip6 proto"
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should chase header chain, but at this moment it does not.
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.BR "ip6 protochain"
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is supplied for this behavior.
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.LP
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Arithmetic expression against transport layer headers, like \fBtcp[0]\fP,
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does not work against IPv6 packets.
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It only looks at IPv4 packets.
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