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tcpbridge(1)			 User Commands			  tcpbridge(1)

NAME
       tcpbridge - Bridge network traffic across two interfaces

SYNOPSIS
       tcpbridge [-flags] [-flag [value]] [--option-name[[=| ]value]]

       All arguments must be options.

       tcpbridge is a tool for selectively bridging network traffic across two
       interfaces and optionally modifying the packets in between

DESCRIPTION
       The basic operation of tcpbridge	is to be a network bridge between  two
       subnets.	 All packets received on one interface are sent	via the	other.

       Optionally,  packets  can  be  edited in	a variety of ways according to
       your needs.

       For more	details, please	see the	 Tcpreplay  Manual  at:	 http://tcpre-
       play.appneta.com

OPTIONS

       -r string, --portmap=string
	      Rewrite TCP/UDP ports.  This option may appear up	to 9999	times.

	      Specify  a  list	of comma delimited port	mappings consisting of
	      colon delimited port number pairs.  Each	colon  delimited  port
	      pair  consists  of the port to match followed by the port	number
	      to rewrite.

	      Examples:
		  --portmap=80:8000 --portmap=8080:80	 # 80->8000 and	8080->80
		  --portmap=8000,8080,88888:80		 # 3 different ports become 80
		  --portmap=8000-8999:80		 # ports 8000 to 8999 become 80

       -s number, --seed=number
	      Randomize	src/dst	IPv4/v6	addresses w/ given seed.  This	option
	      may appear up to 1 times.	 This option must not appear in	combi-
	      nation with any of the following options:	fuzz-seed.   This  op-
	      tion takes an integer number as its argument.

	      Causes the source	and destination	IPv4/v6	addresses to be	pseudo
	      randomized  but  still  maintain	client/server	relationships.
	      Since  the randomization is deterministic	based on the seed, you
	      can reuse	the same seed value to recreate	the traffic.

       -N string, --pnat=string
	      Rewrite IPv4/v6 addresses	using pseudo-NAT.  This	option may ap-
	      pear  up to 2 times.  This option	must not appear	in combination
	      with any of the following	options: srcipmap.

	      Takes a comma delimited series of	colon delimited	CIDR  netblock
	      pairs.   Each netblock pair is evaluated in order	against	the IP
	      addresses.  If the IP address in the packet  matches  the	 first
	      netblock,	 it  is	 rewritten using the second netblock as	a mask
	      against the high order bits.

	      IPv4 Example:
		  --pnat=192.168.0.0/16:10.77.0.0/16,172.16.0.0/12:10.1.0.0/24
	      IPv6 Example:
		  --pnat=[2001:db8::/32]:[dead::/16],[2001:db8::/32]:[::ffff:0:0/96]

       -S string, --srcipmap=string
	      Rewrite source IPv4/v6 addresses using pseudo-NAT.  This	option
	      may appear up to 1 times.	 This option must not appear in	combi-
	      nation with any of the following options:	pnat.

	      Works just like the --pnat option, but only affects  the	source
	      IP addresses in the IPv4/v6 header.

       -D string, --dstipmap=string
	      Rewrite  destination  IPv4/v6  addresses using pseudo-NAT.  This
	      option may appear	up to 1	times.	This option must not appear in
	      combination with any of the following options: pnat.

	      Works just like the --pnat option, but only affects the destina-
	      tion IP addresses	in the IPv4/v6 header.

       -e string, --endpoints=string
	      Rewrite IP addresses to be between two endpoints.	  This	option
	      may  appear  up to 1 times.  This	option must appear in combina-
	      tion with	the following options: cachefile.

	      Takes a pair of colon delimited IPv4/v6 addresses	which will  be
	      used  to	rewrite	all traffic to appear to be between the	two IP
	      addresses.

	      IPv4 Example:
		  --endpoints=172.16.0.1:172.16.0.2
	      IPv6 Example:
		  --endpoints=[2001:db8::dead:beef]:[::ffff:0:0:ac:f:0:2]

       --tcp-sequence=number
	      Change TCP Sequence (and ACK) numbers /w given seed.   This  op-
	      tion takes an integer number as its argument.  The value of num-
	      ber is constrained to being:
		  greater than or equal	to 1
	      The default number for this option is:
		   0

	      Change all TCP sequence numbers, and related sequence-acknowl-
	      edgement numbers.	 They will be shifted by a random amount based
	      on the provided seed.

       -b, --skipbroadcast
	      Skip rewriting broadcast/multicast IPv4/v6 addresses.

	      By default --seed, --pnat	and --endpoints	will rewrite broadcast
	      and multicast IPv4/v6 and	MAC addresses. Setting this flag will
	      keep broadcast/multicast IPv4/v6 and MAC addresses from being
	      rewritten.

       -C, --fixcsum
	      Force recalculation of IPv4/TCP/UDP header checksums.

	      Causes each IPv4/v6 packet to have their checksums recalculated
	      and fixed.  Automatically	enabled	for packets modified with
	      --seed, --pnat, --endpoints or --fixlen.

       -m number, --mtu=number
	      Override default MTU length (1500	bytes).	 This option may ap-
	      pear up to 1 times.  This	option takes an	integer	number as its
	      argument.	 The value of number is	constrained to being:
		  in the range	1 through MAX_SNAPLEN

	      Override the default 1500	byte MTU size for determining the max-
	      imum padding length (--fixlen=pad) or when truncating (--mtu-
	      trunc).

       --mtu-trunc
	      Truncate packets larger then specified MTU.  This	option may ap-
	      pear up to 1 times.

	      Similar to --fixlen, this	option will truncate data in packets
	      from Layer 3 and above to	be no larger then the MTU.

       -E, --efcs
	      Remove Ethernet checksums	(FCS) from end of frames.

	      Note, this option	is pretty dangerous!  We do not	actually check
	      to see if	a FCS actually exists in the frame, we just blindly
	      delete the last 4	bytes.	Hence, you should only use this	if you
	      know know	that your OS provides the FCS when reading raw pack-
	      ets.

       --ttl=string
	      Modify the IPv4/v6 TTL/Hop Limit.

	      Allows you to modify the TTL/Hop Limit of	all the	IPv4/v6	pack-
	      ets.  Specify a number to	hard-code the value or +/-value	to in-
	      crease or	decrease by the	value provided (limited	to 1-255).

	      Examples:
		  --ttl=10
		  --ttl=+7
		  --ttl=-64

       --tos=number
	      Set the IPv4 TOS/DiffServ/ECN byte.  This	option may appear up
	      to 1 times.  This	option takes an	integer	number as its argu-
	      ment.  The value of number is constrained	to being:
		  in the range	0 through 255

	      Allows you to override the TOS (also known as DiffServ/ECN)
	      value in IPv4.

       --tclass=number
	      Set the IPv6 Traffic Class byte.	This option may	appear up to 1
	      times.  This option takes	an integer number as its argument.
	      The value	of number is constrained to being:
		  in the range	0 through 255

	      Allows you to override the IPv6 Traffic Class field.

       --flowlabel=number
	      Set the IPv6 Flow	Label.	This option may	appear up to 1 times.
	      This option takes	an integer number as its argument.  The	value
	      of number	is constrained to being:
		  in the range	0 through 1048575

	      Allows you to override the 20bit IPv6 Flow Label field.  Has no
	      effect on	IPv4 packets.

       -F string, --fixlen=string
	      Pad or truncate packet data to match header length.  This	option
	      may appear up to 1 times.

	      Packets may be truncated during capture if the snaplen is
	      smaller then the packet.	This option allows you to modify the
	      packet to	pad the	packet back out	to the size stored in the
	      IPv4/v6 header or	rewrite	the IP header total length to reflect
	      the stored packet	length.

	      pad Truncated packets will be padded out so that the packet
	      length matches the IPv4 total length

	      trunc Truncated packets will have	their IPv4 total length	field
	      rewritten	to match the actual packet length

	      del Delete the packet

       --fuzz-seed=number
	      Fuzz 1 in	X packets. Edit	bytes, length, or emulate packet drop.
	      This option takes	an integer number as its argument.  The	value
	      of number	is constrained to being:
		  greater than or equal	to 0
	      The default number for this option is:
		   0

	      This fuzzing was designed	as to test layer 7 protocols such as
	      voip protocols.  It modifies randomly 1 out of X packets (where
	      X	= --fuzz-factor) in order for stateful protocols to cover more
	      of their code.  The random fuzzing actions focus on data start
	      and end because it often is the part of the data application
	      protocols	base their decisions on.

	      Possible fuzzing actions list:
	       * drop packet
	       * reduce	packet size
	       * edit packet Bytes:
		 * Not all Bytes have the same probability of appearance in
	      real life.
		   Replace with	0x00, 0xFF, or a random	byte with equal	like-
	      lihood.
		 * Not all Bytes have the same significance in a packet.
		   Replace the start, the end, or the middle of	the packet
	      with equal likelihood.
	       * do nothing (7 out of 8	packets)

       --fuzz-factor=number
	      Set the Fuzz 1 in	X packet ratio (default	1 in 8 packets).  This
	      option must appear in combination	with the following options:
	      fuzz-seed.  This option takes an integer number as its argument.
	      The value	of number is constrained to being:
		  greater than or equal	to 1
	      The default number for this option is:
		   8

	      Sets the ratio of	for --fuzz-seed	option.	By default this	value
	      is 8, which means	1 in 8 packets are modified by fuzzing.	Note
	      that this	ratio is based on the random number generated by the
	      supplied fuzz seed. Therefore by default you cannot expect that
	      exactly every eighth packet will be modified.

       --skipl2broadcast
	      Skip rewriting broadcast/multicast Layer 2 addresses.

	      By default, editing Layer	2 addresses will rewrite broadcast and
	      multicast	MAC addresses.	 Setting this flag will	keep broad-
	      cast/multicast MAC addresses from	being rewritten.

       --dlt=string
	      Override output DLT encapsulation.  This option may appear up to
	      1	times.

	      By default, no DLT (data link type) conversion will be made.  To
	      change the DLT type of the output	pcap, select one of the	fol-
	      lowing values:

	      enet Ethernet aka	DLT_EN10MB

	      hdlc Cisco HDLC aka DLT_C_HDLC

	      jnpr_ether Juniper Ethernet DLT_C_JNPR_ETHER

	      pppserial	PPP Serial aka DLT_PPP_SERIAL

	      user User	specified Layer	2 header and DLT type

       --enet-dmac=string
	      Override destination ethernet MAC	addresses.  This option	may
	      appear up	to 1 times.

	      Takes a pair of comma deliminated	ethernet MAC addresses which
	      will replace the destination MAC address of outbound packets.
	      The first	MAC address will be used for the server	to client
	      traffic and the optional second MAC address will be used for the
	      client to	server traffic.

	      Example:
		  --enet-dmac=00:12:13:14:15:16,00:22:33:44:55:66

       --enet-smac=string
	      Override source ethernet MAC addresses.  This option may appear
	      up to 1 times.

	      Takes a pair of comma deliminated	ethernet MAC addresses which
	      will replace the source MAC address of outbound packets.	The
	      first MAC	address	will be	used for the server to client traffic
	      and the optional second MAC address will be used for the client
	      to server	traffic.

	      Example:
		  --enet-smac=00:12:13:14:15:16,00:22:33:44:55:66

       --enet-subsmac=string
	      Substitute MAC addresses.	 This option may appear	up to 9999
	      times.

	      Allows you to rewrite ethernet MAC addresses of packets. It
	      takes comma delimited pair or MACs address and rewrites all oc-
	      currences	of the first MAC with the value	of the second MAC.
	      Example:
		  --enet-subsmac=00:12:13:14:15:16,00:22:33:44:55:66

       --enet-mac-seed=number
	      Randomize	MAC addresses.	This option may	appear up to 1 times.
	      This option must not appear in combination with any of the fol-
	      lowing options: enet-smac, enet-dmac, enet-subsmac.  This	option
	      takes an integer number as its argument.

	      Allows you to randomize ethernet MAC addresses of	packets,
	      mostly like what --seed option does for IPv4/IPv6	addresses.

       --enet-mac-seed-keep-bytes=number
	      Randomize	MAC addresses.	This option may	appear up to 1 times.
	      This option must appear in combination with the following	op-
	      tions: enet-mac-seed.  This option takes an integer number as
	      its argument.  The value of number is constrained	to being:
		  in the range	1 through 6

	      Keep some	bytes untouched	when usinging --enet-mac-seed option.

       --enet-vlan=string
	      Specify ethernet 802.1q VLAN tag mode.  This option may appear
	      up to 1 times.

	      Allows you to rewrite ethernet frames to add a 802.1q header to
	      standard 802.3 ethernet headers or remove	the 802.1q VLAN	tag
	      information.

	      add Rewrites the existing	802.3 ethernet header as an 802.1q
	      VLAN header

	      del Rewrites the existing	802.1q VLAN header as an 802.3 ether-
	      net header

       --enet-vlan-tag=number
	      Specify the new ethernet 802.1q VLAN tag value.  This option may
	      appear up	to 1 times.  This option must appear in	combination
	      with the following options: enet-vlan.  This option takes	an in-
	      teger number as its argument.  The value of number is con-
	      strained to being:
		  in the range	0 through 4095

       --enet-vlan-cfi=number
	      Specify the ethernet 802.1q VLAN CFI value.  This	option may ap-
	      pear up to 1 times.  This	option must appear in combination with
	      the following options: enet-vlan.	 This option takes an integer
	      number as	its argument.  The value of number is constrained to
	      being:
		  in the range	0 through 1

       --enet-vlan-pri=number
	      Specify the ethernet 802.1q VLAN priority.  This option may ap-
	      pear up to 1 times.  This	option must appear in combination with
	      the following options: enet-vlan.	 This option takes an integer
	      number as	its argument.  The value of number is constrained to
	      being:
		  in the range	0 through 7

       --hdlc-control=number
	      Specify HDLC control value.  This	option may appear up to	1
	      times.  This option takes	an integer number as its argument.

	      The Cisco	HDLC header has	a 1 byte "control" field.  Apparently
	      this should always be 0, but if you can use any 1	byte value.

       --hdlc-address=number
	      Specify HDLC address.  This option may appear up to 1 times.
	      This option takes	an integer number as its argument.

	      The Cisco	HDLC header has	a 1 byte "address" field which has two
	      valid values:

	      0x0F Unicast

	      0xBF Broadcast
	      You can however specify any single byte value.

       --user-dlt=number
	      Set output file DLT type.	 This option may appear	up to 1	times.
	      This option takes	an integer number as its argument.

	      Set the DLT value	of the output pcap file.

       --user-dlink=string
	      Rewrite Data-Link	layer with user	specified data.	 This option
	      may appear up to 2 times.

	      Provide a	series of comma	deliminated hex	values which will be
	      used to rewrite or create	the Layer 2 header of the packets.
	      The first	instance of this argument will rewrite both server and
	      client traffic, but if this argument is specified	a second time,
	      it will be used for the client traffic.

	      Example:
		  --user-dlink=01,02,03,04,05,06,00,1A,2B,3C,4D,5E,6F,08,00

       -d number, --dbug=number
	      Enable debugging output.	This option may	appear up to 1 times.
	      This option takes	an integer number as its argument.  The	value
	      of number	is constrained to being:
		  in the range	0 through 5
	      The default number for this option is:
		   0

	      If configured with --enable-debug, then you can specify a	ver-
	      bosity level for debugging output.  Higher numbers increase ver-
	      bosity.

       -i string, --intf1=string
	      Primary interface	(listen	in uni-directional mode).  This	option
	      may appear up to 1 times.

       -I string, --intf2=string
	      Secondary	interface (send	in uni-directional mode).  This	option
	      may appear up to 1 times.

       -u, --unidir
	      Send and receive in only one direction.  This option may appear
	      up to 1 times.

	      Normally,	tcpbridge will send and	receive	traffic	in both	direc-
	      tions (bi-directionally).	 However, if you choose	this option,
	      traffic will be sent uni-directionally.

       --listnics
	      List available network interfaces	and exit.

       -L number, --limit=number
	      Limit the	number of packets to send.  This option	may appear up
	      to 1 times.  This	option takes an	integer	number as its argu-
	      ment.  The value of number is constrained	to being:
		  greater than or equal	to 1
	      The default number for this option is:
		   -1

	      By default, tcpbridge will send packets forever or until Ctrl-C.
	      Alternatively, you can specify a maximum number of packets to
	      send.

       -M string, --mac=string
	      MAC addresses of local NIC's.  This option may appear up to 2
	      times.

	      tcpbridge	does not support detecting the MAC addresses of	the
	      local network interfaces under Windows.  Please specify both MAC
	      addresses	of the interfaces used in the bridge: -M <intf1	mac>
	      -M <intf2	mac>

       -x string, --include=string
	      Include only packets matching rule.  This	option may appear up
	      to 1 times.  This	option must not	appear in combination with any
	      of the following options:	exclude.

	      Override default of sending all packets stored in	the capture
	      file and only send packets which match the provided rule.	 Rules
	      can be one of:

	      S:_CIDR1_,...  - Source IP must match specified CIDR(s)

	      D:_CIDR1_,...  - Destination IP must match specified CIDR(s)

	      B:_CIDR1_,...  - Both source and destination IP must match spec-
	      ified CIDR(s)

	      E:_CIDR1_,...  - Either IP must match specified CIDR(s)

	      P:_LIST_ - Must be one of	the listed packets where the list cor-
	      responds to the packet number in the capture file.
		  --include=P:1-5,9,15,72-
	      would send packets 1 through 5, the 9th and 15th packet, and
	      packets 72 until the end of the file

	      F:'_bpf_'	- BPF filter.  See the tcpdump(8) man page for syntax.

       -X string, --exclude=string
	      Exclude any packet matching this rule.  This option may appear
	      up to 1 times.  This option must not appear in combination with
	      any of the following options: include.

	      Override default of sending all packets stored in	the capture
	      file and only send packets which do not match the	provided rule.
	      Rules can	be one of:

	      S:_CIDR1_,...  - Source IP must not match	specified CIDR(s)

	      D:_CIDR1_,...  - Destination IP must not match specified CIDR(s)

	      B:_CIDR1_,...  - Both source and destination IP must not match
	      specified	CIDR(s)

	      E:_CIDR1_,...  - Either IP must not match	specified CIDR(s)

	      P:_LIST_ - Must not be one of the	listed packets where the list
	      corresponds to the packet	number in the capture file.
		  --exclude=P:1-5,9,15,72-
	      would drop packets 1 through 5, the 9th and 15th packet, and
	      packets 72 until the end of the file

       -P, --pid
	      Print the	PID of tcpbridge at startup.

       -v, --verbose
	      Print decoded packets via	tcpdump	to STDOUT.  This option	may
	      appear up	to 1 times.

       -A string, --decode=string
	      Arguments	passed to tcpdump decoder.  This option	may appear up
	      to 1 times.  This	option must appear in combination with the
	      following	options: verbose.

	      When enabling verbose mode (-v) you may also specify one or more
	      additional  arguments to pass to tcpdump to modify the way pack-
	      ets are decoded.	By default, -n and -l are used.	  Be  sure  to
	      quote the	arguments like:	--verbose="-axxx" so that they are not
	      interpreted by tcpbridge.	 The following arguments are valid:
		  [ -aAeNqRStuvxX ]
		  [ -E spi@ipaddr algo:secret,... ]
		  [ -s snaplen ]

       -V, --version
	      Print version information.

       -h, --less-help
	      Display less usage information and exit.

       -H, --help
	      Display usage information	and exit.

       -!, --more-help
	      Pass the extended	usage information through a pager.

       --save-opts [=cfgfile]
	      Save the option state to cfgfile.	 The default is	the last con-
	      figuration file listed in	the OPTION PRESETS section, below.
	      The command will exit after updating the config file.

       --load-opts=cfgfile, --no-load-opts
	      Load options from	cfgfile.  The no-load-opts form	will disable
	      the loading of earlier config/rc/ini files.  --no-load-opts is
	      handled early, out of order.

OPTION PRESETS
       Any option that is not marked as	not presettable	may be preset by load-
       ing values from configuration ("RC" or ".INI") file(s).	The homerc
       file is "$$/", unless that is a directory.  In that case, the file
       ".tcpbridgerc" is searched for within that directory.

FILES
       See OPTION PRESETS for configuration files.

EXIT STATUS
       One of the following exit values	will be	returned:

       0  (EXIT_SUCCESS)
	      Successful program execution.

       1  (EXIT_FAILURE)
	      The operation failed or the command syntax was not valid.

       66  (EX_NOINPUT)
	      A	specified configuration	file could not be loaded.

       70  (EX_SOFTWARE)
	      libopts had an internal operational error.  Please report	it to
	      autogen-users@lists.sourceforge.net.  Thank you.

AUTHORS
       Copyright 2013-2018 Fred	Klassen	- AppNeta Copyright 2000-2012 Aaron
       Turner For support please use the tcpreplay-users@lists.sourceforge.net
       mailing list.  The latest version of this software is always available
       from: http://tcpreplay.appneta.com/

COPYRIGHT
       Copyright (C) 2000-2018 Aaron Turner and	Fred Klassen all rights	re-
       served.	This program is	released under the terms of the	GNU General
       Public License, version 3 or later.

BUGS
       Please send bug reports to: tcpreplay-users@lists.sourceforge.net

NOTES
       This manual page	was AutoGen-erated from	the tcpbridge option defini-
       tions.

tcpbridge			  01 Mar 2021			  tcpbridge(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPTION PRESETS | FILES | EXIT STATUS | AUTHORS | COPYRIGHT | BUGS | NOTES

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