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WIRESHARK-FILTER(4)					   WIRESHARK-FILTER(4)

NAME
       wireshark-filter	- Wireshark display filter syntax and reference

SYNOPSIS
       wireshark [other	options] [ -Y "display filter expression" |
       --display-filter	"display filter	expression" ]

       tshark [other options] [	-Y "display filter expression" |
       --display-filter	"display filter	expression" ]

DESCRIPTION
       Wireshark and TShark share a powerful filter engine that	helps remove
       the noise from a	packet trace and lets you see only the packets that
       interest	you. If	a packet meets the requirements	expressed in your
       filter, then it is displayed in the list	of packets. Display filters
       let you compare the fields within a protocol against a specific value,
       compare fields against fields, and check	the existence of specified
       fields or protocols.

       Filters are also	used by	other features such as statistics generation
       and packet list colorization (the latter	is only	available to
       Wireshark). This	manual page describes their syntax. A comprehensive
       reference of filter fields can be found within Wireshark	and in the
       display filter reference	at https://www.wireshark.org/docs/dfref/.

FILTER SYNTAX
   Check whether a field or protocol exists
       The simplest filter allows you to check for the existence of a protocol
       or field. If you	want to	see all	packets	which contain the IP protocol,
       the filter would	be "ip"	(without the quotation marks). To see all
       packets that contain a Token-Ring RIF field, use	"tr.rif".

       Think of	a protocol or field in a filter	as implicitly having the
       "exists"	operator.

   Comparison operators
       Fields can also be compared against values. The comparison operators
       can be expressed	either through English-like abbreviations or through
       C-like symbols:

	   eq, ==    Equal
	   ne, !=    Not Equal
	   gt, >     Greater Than
	   lt, <     Less Than
	   ge, >=    Greater than or Equal to
	   le, <=    Less than or Equal	to

   Search and match operators
       Additional operators exist expressed only in English, not C-like
       syntax:

	   contains	Does the protocol, field or slice contain a value
	   matches, ~	Does the protocol or text string match the given
			case-insensitive Perl-compatible regular expression

       The "contains" operator allows a	filter to search for a sequence	of
       characters, expressed as	a string (quoted or unquoted), or bytes,
       expressed as a byte array, or for a single character, expressed as a
       C-style character constant. For example,	to search for a	given HTTP URL
       in a capture, the following filter can be used:

	   http	contains "https://www.wireshark.org"

       The "contains" operator cannot be used on atomic	fields,	such as
       numbers or IP addresses.

       The "matches"  or "~" operator allows a filter to apply to a specified
       Perl-compatible regular expression (PCRE). The "matches"	operator is
       only implemented	for protocols and for protocol fields with a text
       string representation. Matches are case-insensitive by default. For
       example,	to search for a	given WAP WSP User-Agent, you can write:

	   wsp.header.user_agent matches "cldc"

       This would match	"cldc",	"CLDC",	"cLdC" or any other combination	of
       upper and lower case letters.

       You can force case sensitivity using

	   wsp.header.user_agent matches "(?-i)cldc"

       This is an example of PCRE's (?*option)*	construct. (?-i) performs a
       case-sensitive pattern match but	other options can be specified as
       well. More information can be found in the
       pcrepattern(3)|https://www.pcre.org/original/doc/html/pcrepattern.html
       man page.

   Functions
       The filter language has the following functions:

	   upper(string-field) - converts a string field to uppercase
	   lower(string-field) - converts a string field to lowercase
	   len(field)	       - returns the byte length of a string or	bytes field
	   count(field)	       - returns the number of field occurrences in a frame
	   string(field)       - converts a non-string field to	string

       upper() and lower() are useful for performing case-insensitive string
       comparisons. For	example:

	   upper(ncp.nds_stream_name) contains "MACRO"
	   lower(mount.dump.hostname) == "angel"

       string()	converts a field value to a string, suitable for use with
       operators like "matches"	or "contains". Integer fields are converted to
       their decimal representation. It	can be used with IP/Ethernet addresses
       (as well	as others), but	not with string	or byte	fields.	For example:

	   string(frame.number)	matches	"[13579]$"

       gives you all the odd packets.

   Protocol field types
       Each protocol field is typed. The types are:

	   ASN.1 object	identifier
	   Boolean
	   Character string
	   Compiled Perl-Compatible Regular Expression (GRegex)	object
	   Date	and time
	   Ethernet or other MAC address
	   EUI64 address
	   Floating point (double-precision)
	   Floating point (single-precision)
	   Frame number
	   Globally Unique Identifier
	   IPv4	address
	   IPv6	address
	   IPX network number
	   Label
	   Protocol
	   Sequence of bytes
	   Signed integer, 1, 2, 3, 4, or 8 bytes
	   Time	offset
	   Unsigned integer, 1,	2, 3, 4, or 8 bytes
	   1-byte ASCII	character

       An integer may be expressed in decimal, octal, or hexadecimal notation,
       or as a C-style character constant. The following six display filters
       are equivalent:

	   frame.len > 10
	   frame.len > 012
	   frame.len > 0xa
	   frame.len > '\n'
	   frame.len > '\x0a'
	   frame.len > '\012'

       Boolean values are either true or false.	In a display filter expression
       testing the value of a Boolean field, "true" is expressed as 1 or any
       other non-zero value, and "false" is expressed as zero. For example, a
       token-ring packet's source route	field is Boolean. To find any
       source-routed packets, a	display	filter would be:

	   tr.sr == 1

       Non source-routed packets can be	found with:

	   tr.sr == 0

       Ethernet	addresses and byte arrays are represented by hex digits. The
       hex digits may be separated by colons, periods, or hyphens:

	   eth.dst eq ff:ff:ff:ff:ff:ff
	   aim.data == 0.1.0.d
	   fddi.src == aa-aa-aa-aa-aa-aa
	   echo.data ==	7a

       IPv4 addresses can be represented in either dotted decimal notation or
       by using	the hostname:

	   ip.src == 192.168.1.1
	   ip.dst eq www.mit.edu

       IPv4 addresses can be compared with the same logical relations as
       numbers:	eq, ne,	gt, ge,	lt, and	le. The	IPv4 address is	stored in host
       order, so you do	not have to worry about	the endianness of an IPv4
       address when using it in	a display filter.

       Classless Inter-Domain Routing (CIDR) notation can be used to test if
       an IPv4 address is in a certain subnet. For example, this display
       filter will find	all packets in the 129.111 network:

	   ip.addr == 129.111.0.0/16

       Remember, the number after the slash represents the number of bits used
       to represent the	network. CIDR notation can also	be used	with
       hostnames, as in	this example of	finding	IP addresses on	the same
       network as 'sneezy' (requires that 'sneezy' resolve to an IP address
       for filter to be	valid):

	   ip.addr eq sneezy/24

       The CIDR	notation can only be used on IP	addresses or hostnames,	not in
       variable	names. So, a display filter like "ip.src/24 == ip.dst/24" is
       not valid (yet).

       Transaction and other IDs are often represented by unsigned 16 or 32
       bit integers and	formatted as a hexadecimal string with "0x" prefix:

	   (dhcp.id == 0xfe089c15) || (ip.id ==	0x0373)

       Strings are enclosed in double quotes:

	   http.request.method == "POST"

       Inside double quotes, you may use a backslash to	embed a	double quote
       or an arbitrary byte represented	in either octal	or hexadecimal.

	   browser.comment == "An embedded \" double-quote"

       Use of hexadecimal to look for "HEAD":

	   http.request.method == "\x48EAD"

       Use of octal to look for	"HEAD":

	   http.request.method == "\110EAD"

       This means that you must	escape backslashes with	backslashes inside
       double quotes.

	   smb.path contains "\\\\SERVER\\SHARE"

       looks for \\SERVER\SHARE	in "smb.path". This may	be more	conveniently
       written as

	   smb.path contains r"\\SERVER\SHARE"

       String literals prefixed	with 'r' are called "raw strings". Such
       strings treat backslash as a literal character. Double quotes may still
       be escaped with backslash but note that backslashes are always
       preserved in the	result.

   The slice operator
       You can take a slice of a field if the field is a text string or	a byte
       array. For example, you can filter on the vendor	portion	of an ethernet
       address (the first three	bytes) like this:

	   eth.src[0:3]	== 00:00:83

       Another example is:

	   http.content_type[0:4] == "text"

       You can use the slice operator on a protocol name, too. The "frame"
       protocol	can be useful, encompassing all	the data captured by Wireshark
       or TShark.

	   token[0:5] ne 0.0.0.1.1
	   llc[0] eq aa
	   frame[100-199] contains "wireshark"

       The following syntax governs slices:

	   [i:j]    i =	start_offset, j	= length
	   [i-j]    i =	start_offset, j	= end_offset, inclusive.
	   [i]	    i =	start_offset, length = 1
	   [:j]	    start_offset = 0, length = j
	   [i:]	    start_offset = i, end_offset = end_of_field

       Offsets can be negative,	in which case they indicate the	offset from
       the end of the field. The last byte of the field	is at offset -1, the
       last but	one byte is at offset -2, and so on. Here's how	to check the
       last four bytes of a frame:

	   frame[-4:4] == 0.1.2.3

       or

	   frame[-4:] == 0.1.2.3

       A slice is always compared against either a string or a byte sequence.
       As a special case, when the slice is only 1 byte	wide, you can compare
       it against a hex	integer	that is	0xff or	less (which means it fits
       inside one byte). This is not allowed for byte sequences	greater	than
       one byte, because then one would	need to	specify	the endianness of the
       multi-byte integer. Also, this is not allowed for decimal numbers,
       since they would	be confused with hex numbers that are already allowed
       as byte strings.	Nevertheless, single-byte hex integers can be
       convenient:

	   frame[4] == 0xff

       Slices can be combined. You can concatenate them	using the comma
       operator:

	   ftp[1,3-5,9:] == 01:03:04:05:09:0a:0b

       This concatenates offset	1, offsets 3-5,	and offset 9 to	the end	of the
       ftp data.

   The membership operator
       A field may be checked for matches against a set	of values simply with
       the membership operator.	For instance, you may find traffic on common
       HTTP/HTTPS ports	with the following filter:

	   tcp.port in {80, 443, 8080}

       as opposed to the more verbose:

	   tcp.port == 80 or tcp.port == 443 or	tcp.port == 8080

       To find HTTP requests using the HEAD or GET methods:

	   http.request.method in {"HEAD", "GET"}

       The set of values can also contain ranges:

	   tcp.port in {443, 4430..4434}
	   ip.addr in {10.0.0.5	.. 10.0.0.9, 192.168.1.1..192.168.1.9}
	   frame.time_delta in {10 .. 10.5}

   Type	conversions
       If a field is a text string or a	byte array, it can be expressed	in
       whichever way is	most convenient.

       So, for instance, the following filters are equivalent:

	   http.request.method == "GET"
	   http.request.method == 47.45.54

       A range can also	be expressed in	either way:

	   frame[60:2] gt 50.51
	   frame[60:2] gt "PQ"

   Bit field operations
       It is also possible to define tests with	bit field operations.
       Currently the following bit field operation is supported:

	   bitwise_and,	&	 Bitwise AND

       The bitwise AND operation allows	testing	to see if one or more bits are
       set. Bitwise AND	operates on integer protocol fields and	slices.

       When testing for	TCP SYN	packets, you can write:

	   tcp.flags & 0x02

       That expression will match all packets that contain a "tcp.flags" field
       with the	0x02 bit, i.e. the SYN bit, set.

       Similarly, filtering for	all WSP	GET and	extended GET methods is
       achieved	with:

	   wsp.pdu_type	& 0x40

       When using slices, the bit mask must be specified as a byte string, and
       it must have the	same number of bytes as	the slice itself, as in:

	   ip[42:2] & 40:ff

   Logical expressions
       Tests can be combined using logical expressions.	These too are
       expressible in C-like syntax or with English-like abbreviations:

	   and,	&&   Logical AND
	   or,	||   Logical OR
	   not,	! Logical NOT

       Expressions can be grouped by parentheses as well. The following	are
       all valid display filter	expressions:

	   tcp.port == 80 and ip.src ==	192.168.2.1
	   not llc
	   http	and frame[100-199] contains "wireshark"
	   (ipx.src.net	== 0xbad && ipx.src.node == 0.0.0.0.0.1) || ip

       Remember	that whenever a	protocol or field name occurs in an
       expression, the "exists"	operator is implicitly called. The "exists"
       operator	has the	highest	priority. This means that the first filter
       expression must be read as "show	me the packets for which tcp.port
       exists and equals 80, and ip.src	exists and equals 192.168.2.1".	The
       second filter expression	means "show me the packets where not exists
       llc", or	in other words "where llc does not exist" and hence will match
       all packets that	do not contain the llc protocol. The third filter
       expression includes the constraint that offset 199 in the frame exists,
       in other	words the length of the	frame is at least 200.

       Each comparison has an implicit exists test for any field value.	Care
       must be taken when using	the display filter to remove noise from	the
       packet trace. If, for example, you want to filter out all IP multicast
       packets to address 224.1.2.3, then using:

	   ip.dst ne 224.1.2.3

       may be too restrictive. This is the same	as writing:

	   ip.dst and ip.dst ne	224.1.2.3

       The filter selects only frames that have	the "ip.dst" field. Any	other
       frames, including all non-IP packets, will not be displayed. To display
       the non-IP packets as well, you can use one of the following two
       expressions:

	   not ip.dst or ip.dst	ne 224.1.2.3
	   not ip.dst eq 224.1.2.3

       The first filter	uses "not ip.dst" to include all non-IP	packets	and
       then lets "ip.dst ne 224.1.2.3" filter out the unwanted IP packets. The
       second filter also negates the implicit existance test and so is	a
       shorter way to write the	first.

FILTER FIELD REFERENCE
       The entire list of display filters is too large to list here. You can
       can find	references and examples	at the following locations:

       o   The online Display Filter Reference:
	   https://www.wireshark.org/docs/dfref/

       o   View:Internals:Supported Protocols in Wireshark

       o   tshark -G fields on the command line

       o   The Wireshark wiki:
	   https://gitlab.com/wireshark/wireshark/-/wikis/DisplayFilters

NOTES
       The wireshark-filter(4) manpage is part of the Wireshark	distribution.
       The latest version of Wireshark can be found at
       https://www.wireshark.org.

       Regular expressions in the "matches" operator are provided by GRegex in
       GLib. See
       https://developer-old.gnome.org/glib/stable/glib-regex-syntax.html or
       https://www.pcre.org/ for more information.

       This manpage does not describe the capture filter syntax, which is
       different. See the manual page of pcap-filter(7)	or, if that doesn't
       exist, tcpdump(8), or, if that doesn't exist,
       https://gitlab.com/wireshark/wireshark/-/wikis/CaptureFilters for a
       description of capture filters.

       Display Filters are also	described in the User's	Guide:
       https://www.wireshark.org/docs/wsug_html_chunked/ChWorkBuildDisplayFilterSection.html

SEE ALSO
       wireshark(1), tshark(1),	editcap(1), pcap(3), pcap-filter(7) or
       tcpdump(8) if it	doesn't	exist.

AUTHORS
       See the list of authors in the Wireshark	man page for a list of authors
       of that code.

				  2022-03-23		   WIRESHARK-FILTER(4)

NAME | SYNOPSIS | DESCRIPTION | FILTER SYNTAX | FILTER FIELD REFERENCE | NOTES | SEE ALSO | AUTHORS

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