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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> ] [ -v ] <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, with spaces
       separating the bytes from each other.  Each line begins with an offset
       describing the position in the packet, each new packet starts with an
       offset of 0 and there is a space separating the offset from the
       following bytes.  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 0e b6 00 00 02 00 0e b6 00 00 01 08 00 45 00
           000010 00 28 00 00 00 00 ff 01 37 d1 c0 00 02 01 c0 00
           000020 02 02 08 00 a6 2f 00 01 00 01 48 65 6c 6c 6f 20
           000030 57 6f 72 6c 64 21
           000036

       Note the last byte must either be followed by the expected next offset
       value as in the example above or a space or a line-end character(s).

       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 one 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).  See
           <http://www.iana.org/assignments/protocol-numbers/protocol-numbers.xhtml>
           for the complete list of assigned internet protocol numbers.

       -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 262144.  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.

       -v  Print the version and exit.

       -4 <srcip>,<destip>
           Prepend dummy IP header with specified IPv4 dest and source
           address.  This option should be accompanied by one of the following
           options: -i, -s, -S, -T, -u Use this option to apply "custom" IP
           addresses.  Example: -4 10.0.0.1,10.0.0.2 to use 10.0.0.1 and
           10.0.0.2 for all IP packets.

       -6 <srcip>,<destip>
           Prepend dummy IP header with specified IPv6 dest and source
           address.  This option should be accompanied by one of the following
           options: -i, -s, -S, -T, -u Use this option to apply "custom" IP
           addresses.  Example: -6 fe80:0:0:0:202:b3ff:fe1e:8329,
           2001:0db8:85a3:0000:0000:8a2e:0370:7334 to use
           fe80:0:0:0:202:b3ff:fe1e:8329 and
           2001:0db8:85a3:0000:0000:8a2e:0370:7334 for all IP 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 <https://www.wireshark.org>.


AUTHORS

         Ashok Narayanan          <ashokn[AT]cisco.com>



2.4.1                             2017-08-29                      text2pcap(1)

wireshark 2.4.1 - Generated Wed Aug 30 15:14:14 CDT 2017
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