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CentOS 7.0 - man page for text2pcap (centos section 1)

TEXT2PCAP(1)			  The Wireshark Network Analyzer		     TEXT2PCAP(1)

NAME
       text2pcap - Generate a capture file from an ASCII hexdump of packets

SYNOPSIS
       text2pcap [ -a ] [ -d ] [ -D ] [ -e <l3pid> ] [ -h ] [ -i <proto> ] [ -l <typenum> ]
       [ -n ] [ -m <max-packet> ] [ -o hex|oct|dec ] [ -q ] [ -s <srcport>,<destport>,<tag> ]
       [ -S <srcport>,<destport>,<ppi> ] [ -t <timefmt> ] [ -T <srcport>,<destport> ]
       [ -u <srcport>,<destport> ] <infile>|- <outfile>|-

DESCRIPTION
       Text2pcap is a program that reads in an ASCII hex dump and writes the data described into
       a pcap capture file.  text2pcap can read hexdumps with multiple packets in them, and build
       a capture file of multiple packets.  text2pcap is also capable of generating dummy
       Ethernet, IP and UDP, TCP, or SCTP headers, in order to build fully processable packet
       dumps from hexdumps of application-level data only.

       Text2pcap understands a hexdump of the form generated by od -Ax -tx1 -v.  In other words,
       each byte is individually displayed and surrounded with a space. Each line begins with an
       offset describing the position in the file. The offset is a hex number (can also be octal
       or decimal - see -o), of more than two hex digits.  Here is a sample dump that text2pcap
       can recognize:

	   000000 00 e0 1e a7 05 6f 00 10 ........
	   000008 5a a0 b9 12 08 00 46 00 ........
	   000010 03 68 00 00 00 00 0a 2e ........
	   000018 ee 33 0f 19 08 7f 0f 19 ........
	   000020 03 80 94 04 00 00 10 01 ........
	   000028 16 a2 0a 00 03 50 00 0c ........
	   000030 01 01 0f 19 03 80 11 01 ........

       There is no limit on the width or number of bytes per line. Also the text dump at the end
       of the line is ignored. Bytes/hex numbers can be uppercase or lowercase. Any text before
       the offset is ignored, including email forwarding characters '>'. Any lines of text
       between the bytestring lines is ignored. The offsets are used to track the bytes, so
       offsets must be correct. Any line which has only bytes without a leading offset is
       ignored. An offset is recognized as being a hex number longer than two characters. Any
       text after the bytes is ignored (e.g. the character dump). Any hex numbers in this text
       are also ignored. An offset of zero is indicative of starting a new packet, so a single
       text file with a series of hexdumps can be converted into a packet capture with multiple
       packets. Packets may be preceded by a timestamp. These are interpreted according to the
       format given on the command line (see -t). If not, the first packet is timestamped with
       the current time the conversion takes place. Multiple packets are written with timestamps
       differing by one microsecond each.  In general, short of these restrictions, text2pcap is
       pretty liberal about reading in hexdumps and has been tested with a variety of mangled
       outputs (including being forwarded through email multiple times, with limited line wrap
       etc.)

       There are a couple of other special features to note. Any line where the first non-
       whitespace character is '#' will be ignored as a comment. Any line beginning with
       #TEXT2PCAP is a directive and options can be inserted after this command to be processed
       by text2pcap. Currently there are no directives implemented; in the future, these may be
       used to give more fine grained control on the dump and the way it should be processed e.g.
       timestamps, encapsulation type etc.

       Text2pcap also allows the user to read in dumps of application-level data, by inserting
       dummy L2, L3 and L4 headers before each packet. The user can elect to insert Ethernet
       headers, Ethernet and IP, or Ethernet, IP and UDP/TCP/SCTP headers before each packet.
       This allows Wireshark or any other full-packet decoder to handle these dumps.

OPTIONS
       -a  Enables ASCII text dump identification. It allows to identify the start of the ASCII
	   text dump and not include it in the packet even if it looks like HEX.

	   NOTE: Do not enable it if the input file does not contain the ASCII text dump.

       -d  Displays debugging information during the process. Can be used multiple times to
	   generate more debugging information.

       -D  The text before the packet starts either with an I or O indicating that the packet is
	   inbound or outbound.  This is only stored if the output format is PCAP-NG.

       -e <l3pid>
	   Include a dummy Ethernet header before each packet. Specify the L3PID for the Ethernet
	   header in hex. Use this option if your dump has Layer 3 header and payload (e.g. IP
	   header), but no Layer 2 encapsulation. Example: -e 0x806 to specify an ARP packet.

	   For IP packets, instead of generating a fake Ethernet header you can also use -l 101
	   to indicate a raw IP packet to Wireshark. Note that -l 101 does not work for any non-
	   IP Layer 3 packet (e.g. ARP), whereas generating a dummy Ethernet header with -e works
	   for any sort of L3 packet.

       -h  Displays a help message.

       -i <proto>
	   Include dummy IP headers before each packet. Specify the IP protocol for the packet in
	   decimal. Use this option if your dump is the payload of an IP packet (i.e. has
	   complete L4 information) but does not have an IP header with each packet. Note that an
	   appropriate Ethernet header is automatically included with each packet as well.
	   Example: -i 46 to specify an RSVP packet (IP protocol 46).

       -l  Specify the link-layer header type of this packet.  Default is Ethernet (1).  See
	   <http://www.tcpdump.org/linktypes.html> for the complete list of possible
	   encapsulations.  Note that this option should be used if your dump is a complete hex
	   dump of an encapsulated packet and you wish to specify the exact type of
	   encapsulation.  Example: -l 7 for ARCNet packets encapsulated BSD-style.

       -m <max-packet>
	   Set the maximum packet length, default is 65535.  Useful for testing various packet
	   boundaries when only an application level datastream is available.  Example:

	   od -Ax -tx1 -v stream | text2pcap -m1460 -T1234,1234 - stream.pcap

	   will convert from plain datastream format to a sequence of Ethernet TCP packets.

       -n  Write PCAP-NG file instead of a PCAP.

       -o hex|oct|dec
	   Specify the radix for the offsets (hex, octal or decimal). Defaults to hex. This
	   corresponds to the "-A" option for od.

       -q  Be completely quiet during the process.

       -s <srcport>,<destport>,<tag>
	   Include dummy SCTP headers before each packet.  Specify, in decimal, the source and
	   destination SCTP ports, and verification tag, for the packet.  Use this option if your
	   dump is the SCTP payload of a packet but does not include any SCTP, IP or Ethernet
	   headers.  Note that appropriate Ethernet and IP headers are automatically also
	   included with each packet.  A CRC32C checksum will be put into the SCTP header.

       -S <srcport>,<destport>,<ppi>
	   Include dummy SCTP headers before each packet.  Specify, in decimal, the source and
	   destination SCTP ports, and a verification tag of 0, for the packet, and prepend a
	   dummy SCTP DATA chunk header with a payload protocol identifier if ppi.  Use this
	   option if your dump is the SCTP payload of a packet but does not include any SCTP, IP
	   or Ethernet headers.  Note that appropriate Ethernet and IP headers are automatically
	   included with each packet.  A CRC32C checksum will be put into the SCTP header.

       -t <timefmt>
	   Treats the text before the packet as a date/time code; timefmt is a format string of
	   the sort supported by strptime(3).  Example: The time "10:15:14.5476" has the format
	   code "%H:%M:%S."

	   NOTE: The subsecond component delimiter must be specified (.) but no pattern is
	   required; the remaining number is assumed to be fractions of a second.

	   NOTE: Date/time fields from the current date/time are used as the default for
	   unspecified fields.

       -T <srcport>,<destport>
	   Include dummy TCP headers before each packet. Specify the source and destination TCP
	   ports for the packet in decimal. Use this option if your dump is the TCP payload of a
	   packet but does not include any TCP, IP or Ethernet headers. Note that appropriate
	   Ethernet and IP headers are automatically also included with each packet.  Sequence
	   numbers will start at 0.

       -u <srcport>,<destport>
	   Include dummy UDP headers before each packet. Specify the source and destination UDP
	   ports for the packet in decimal. Use this option if your dump is the UDP payload of a
	   packet but does not include any UDP, IP or Ethernet headers. Note that appropriate
	   Ethernet and IP headers are automatically also included with each packet.  Example:
	   -u1000,69 to make the packets look like TFTP/UDP packets.

SEE ALSO
       od(1), pcap(3), wireshark(1), tshark(1), dumpcap(1), mergecap(1), editcap(1), strptime(3),
       pcap-filter(7) or tcpdump(8)

NOTES
       Text2pcap is part of the Wireshark distribution.  The latest version of Wireshark can be
       found at <http://www.wireshark.org>.

AUTHORS
	 Ashok Narayanan	  <ashokn[AT]cisco.com>

1.10.3					    2013-07-29				     TEXT2PCAP(1)


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