mausezahn(8) — Linux manual page


MAUSEZAHN(8)               netsniff-ng toolkit              MAUSEZAHN(8)

NAME         top

       mausezahn - a fast versatile packet generator with Cisco-cli

SYNOPSIS         top

       mausezahn { [options] "<arg-string> | <hex-string>" }

DESCRIPTION         top

       mausezahn is a fast traffic generator which allows you to send
       nearly every possible and impossible packet. In contrast to
       trafgen(8), mausezahn's packet configuration is on a protocol-
       level instead of byte-level and mausezahn also comes with a
       built-in Cisco-like command-line interface, making it suitable as
       a network traffic generator box in your network lab.

       Next to network labs, it can also be used as a didactical tool
       and for security audits including penetration and DoS testing. As
       a traffic generator, mausezahn is also able to test IP multicast
       or VoIP networks. Packet rates close to the physical limit are
       reachable, depending on the hardware platform.

       mausezahn supports two modes, ''direct mode'' and a multi-
       threaded ''interactive mode''.

       The ''direct mode'' allows you to create a packet directly on the
       command line and every packet parameter is specified in the
       argument list when calling mausezahn.

       The ''interactive mode'' is an advanced multi-threaded
       configuration mode with its own command line interface (CLI).
       This mode allows you to create an arbitrary number of packet
       types and streams in parallel, each with different parameters.

       The interactive mode utilizes a completely redesigned and more
       flexible protocol framework called ''mops'' (mausezahn's own
       packet system). The look and feel of the CLI is very close to the
       Cisco IOS^tm command line interface.

       You can start the interactive mode by executing mausezahn with
       the ''-x'' argument (an optional port number may follow,
       otherwise it is 25542). Then use telnet(1) to connect to this
       mausezahn instance. If not otherwise specified, the default login
       and password combination is mz:mz and the enable password is:
       mops.  This can be changed in /etc/netsniff-ng/mausezahn.conf.

       The direct mode supports two specification schemes: The ''raw-
       layer-2'' scheme, where every single byte to be sent can be
       specified, and ''higher-layer'' scheme, where packet builder
       interfaces are used (using the ''-t'' option).

       To use the ''raw-layer-2'' scheme, simply specify the desired
       frame as a hexadecimal sequence (the ''hex-string''), such as:

         mausezahn eth0 "00:ab:cd:ef:00 00:00:00:00:00:01 08:00

       In this example, whitespaces within the byte string are optional
       and separate the Ethernet fields (destination and source address,
       type field, and a short payload). The only additional options
       supported are ''-a'', ''-b'', ''-c'', and ''-p''. The frame
       length must be greater than or equal to 15 bytes.

       The ''higher-layer'' scheme is enabled using the ''-t <packet-
       type>'' option.  This option activates a packet builder, and
       besides the ''packet-type'', an optional ''arg-string'' can be
       specified. The ''arg-string'' contains packet- specific
       parameters, such as TCP flags, port numbers, etc. (see example

OPTIONS         top

       mausezahn provides a built-in context-specific help. Append the
        ''help'' after the configuration options. The most important
       options are:

   -x [<port>]
       Start mausezahn in interactive mode with a Cisco-like CLI. Use
       telnet to log into the local mausezahn instance. If no port has
       been specified, port 25542 is used by default.

       Specify IPv6 mode (IPv4 is the default).

   -l <IP>
       Specify the IP address mausezahn should bind to when in
       interactive mode, default:

   -R <PRIO>
       Set priority of sent packets. This configures SO_PRIORITY at the
       socket through which the packets are sent. Usual priority numbers
       are 0..15, but the value can also be a class ID for purposes of
       Qdisc classification. In that case, a class ID such is 1234:5678
       would be specified as 0x12345678.

       Verbose mode. Capital -V is even more verbose.

       Simulation mode, i.e. don't put anything on the wire. This is
       typically combined with the verbose mode.

       Quiet mode where only warnings and errors are displayed.

   -c <count>
       Send the packet count times (default: 1, infinite: 0).

   -d <delay>
       Apply delay between transmissions. The delay value can be
       specified in usec (default, no additional unit needed), or in
       msec (e.g. 100m or 100msec), or in seconds (e.g. 100s or 100sec).
       Note: mops also supports nanosecond delay resolution if you need
       it (see interactive mode).

       Multiply the specified delay with a random value.

   -p <length>
       Pad the raw frame to specified length using zero bytes. Note that
       for raw layer 2 frames the specified length defines the whole
       frame length, while for higher layer packets the number of
       additional padding bytes are specified.

   -a <src-mac|keyword>
       Use specified source MAC address with hexadecimal notation such
       as 00:00:aa:bb:cc:dd.  By default the interface MAC address will
       be used. The keywords ''rand'' and ''own'' refer to a random MAC
       address (only unicast addresses are created) and the own address,
       respectively. You can also use the keywords mentioned below
       although broadcast-type source addresses are officially invalid.

   -b <dst-mac|keyword>
       Use specified destination MAC address. By default, a broadcast is
       sent in raw layer 2 mode or to the destination hosts or gateway
       interface MAC address in normal (IP) mode. You can use the same
       keywords as mentioned above, as well as ''bc'' or ''bcast'',
       ''cisco'', and ''stp''.

   -A <src-ip|range|rand>
       Use specified source IP address, default is own interface
       address. Optionally, the keyword ''rand'' can again be used for a
       random source IP address or a range can be specified, such as
       '''' or ''''.  Also, a DNS
       name can be specified for which mausezahn tries to determine the
       corresponding IP address automatically.

   -B <dst-ip|range>
       Use specified destination IP address (default is broadcast i.e.  As with the source address (see above) you can
       also specify a range or a DNS name.

   -t <packet-type [help] | help>
       Create the specified packet type using the built-in packet
       builder. Currently, supported packet types are: ''arp'',
       ''bpdu'', ''ip'', ''udp'', ''tcp'', ''rtp'', and ''dns''.
       Currently, there is also limited support for ''icmp''. Type
        ''-t help'' to verify which packet builders your actual
       mausezahn version supports. Also, for any particular packet type,
       for example ''tcp'' type
        ''mausezahn -t tcp help'' to receive a more in-depth context
       specific help.

   -T <packet-type>
       Make this mausezahn instance the receiving station. Currently,
       only ''rtp'' is an option here and provides precise jitter
       measurements. For this purpose, start another mausezahn instance
       on the sending station and the local receiving station will
       output jitter statistics. See ''mausezahn -T rtp help'' for a
       detailed help.

   -Q <[CoS:]vlan> [, <[CoS:]vlan>, ...]
       Specify 802.1Q VLAN tag and optional Class of Service. An
       arbitrary number of VLAN tags can be specified (that is, you can
       simulate QinQ or even QinQinQinQ..).  Multiple tags must be
       separated via a comma or a period (e.g. "5:10,20,2:30").  VLAN
       tags are not supported for ARP and BPDU packets (in which case
       you could specify the whole frame in hexadecimal using the raw
       layer 2 interface of mausezahn).

   -M <label[:cos[:ttl]][bos]> [, <label...>]
       Specify a MPLS label or even a MPLS label stack. Optionally, for
       each label the experimental bits (usually the Class of Service,
       CoS) and the Time To Live (TTL) can be specified. If you are
       really crazy you can set and unset the Bottom of Stack (BoS) bit
       for each label using the ''S'' (set) and ''s'' (unset) option. By
       default, the BoS is set automatically and correctly. Any other
       setting will lead to invalid frames. Enter ''-M help'' for
       detailed instructions and examples.

   -P <ascii-payload>
       Specify a cleartext payload. Alternatively, each packet type
       supports a hexadecimal specification of the payload (see for
       example ''-t udp help'').

   -f <filename>
       Read the ASCII payload from the specified file.

   -F <filename>
       Read the hexadecimal payload from the specified file. Actually,
       this file must be also an ASCII text file, but must contain
       hexadecimal digits, e.g. "aa:bb:cc:0f:e6...".  You can use also
       spaces as separation characters.

USAGE EXAMPLE         top

       For more comprehensive examples, have a look at the two following
       HOWTO sections.

   mausezahn eth0 -c 0 -d 2s -t bpdu vlan=5
       Send BPDU frames for VLAN 5 as used with Cisco's PVST+ type of
       STP. By default mausezahn assumes that you want to become the
       root bridge.

   mausezahn eth0 -c 128000 -a rand -p 64
       Perform a CAM table overflow attack.

   mausezahn eth0 -c 0 -Q 5,100 -t tcp flags=syn,dp=1-1023 -p 20 -A rand
       Perform a SYN flood attack to another VLAN using VLAN hopping.
       This only works if you are connected to the same VLAN which is
       configured as native VLAN on the trunk. We assume that the victim
       VLAN is VLAN 100 and the native VLAN is VLAN 5.  Lets attack
       every host in VLAN 100 which use an IP prefix of,
       also try out all ports between 1 and 1023 and use a random source
       IP address.

   mausezahn eth0 -c 0 -d 10msec -B -t udp dp=32000,dscp=46 -P
       Multicast test packet
       Send IP multicast packets to the multicast group using
       a UDP header with destination port 32000 and set the IP DSCP
       field to EF (46). Send one frame every 10 msec.

   mausezahn eth0 -Q 6:420 -M 100,200,300:5 -A -B -t udp sp=666,dp=1-65535 -p 1000 -c 10
       Send UDP packets to the destination host
       using all possible destination ports and send every packet with
       all possible source addresses of the range;
       additionally use a source port of 666 and three MPLS labels, 100,
       200, and 300, the outer (300) with QoS field 5.  Send the frame
       with a VLAN tag 420 and CoS 6; eventually pad with 1000 bytes and
       repeat the whole thing 10 times.

   mausezahn -t syslog sev=3 -P Main reactor reached critical
       temperature. -A -B -c 6 -d 10s
       Send six forged syslog messages with severity 3 to a Syslog
       server; use a forged source IP address and
       let mausezahn decide which local interface to use. Use an inter-
       packet delay of 10 seconds.

   mausezahn -t tcp flags=syn|urg|rst, sp=145, dp=145, win=0,
       s=0-4294967295, ds=1500, urg=666 -a bcast -b bcast -A bcast -B -p 5
       Send an invalid TCP packet with only a 5 byte payload as layer-2
       broadcast and also use the broadcast MAC address as source
       address. The target should be but use a broadcast source
       address. The source and destination port shall be 145 and the
       window size 0. Set the TCP flags SYN, URG, and RST simultaneously
       and sweep through the whole TCP sequence number space with an
       increment of 1500. Finally set the urgent pointer to 666, i.e.
       pointing to nowhere.


       When mausezahn is run in interactive mode it automatically looks
       for and reads a configuration file located at /etc/netsniff-
       ng/mausezahn.conf for custom options if the file is available,
       otherwise it uses defaults set at compile time.

   Config file: /etc/netsniff-ng/mausezahn.conf
       The configuration file contains lines of the form:

            option = value

       Options supported in the configuration file are:
          Option:        Description:

          user           Username for authentication (default: mz)
          password       Password for authentication (default: mz)
          enable              Password to enter privilege mode (default:
          port           The listening port for the CLI (default: 25542)
          listen-addr         IP address to bind CLI to (default:
          management-only     Set management interface (no data traffic
       is allowed to pass through)
          cli-device          Interface to bind CLI to (default: all)
       *not fully implemented*
          automops         Path to automops file (contains XML data
       describing protocols) *in development*

        $ cat /etc/netsniff-ng/mausezahn.conf
        user = mzadmin
        password = mzpasswd
        enable = privilege-mode-passwd
        port = 65000
        listen-addr =


       Using the interactive mode requires starting mausezahn as a

         # mausezahn -x

       Now you can telnet(1) to that server using the default port
       number 25542, but also an arbitrary port number can be specified:

         # mausezahn -x 99
         mausezahn accepts incoming telnet connections on port 99.
         mz: Problems opening config file. Will use defaults

       Either from another terminal or from another host try to telnet
       to the mausezahn server:

         caprica$ telnet galactica 99
         Connected to galactica.
         Escape character is '^]'.
         mausezahn <version>

         Username: mz
         Password: mz

         mz> enable
         Password: mops

       It is recommended to configure your own login credentials in
       /etc/netsniff-ng/mausezahn.conf, (see configuration file section)

       Since you reached the mausezahn prompt, lets try some common
       commands. You can use the '?' character at any time for context-
       specific help. Note that Cisco-like short form of commands are
       accepted in interactive mode. For example, one can use "sh pac"
       instead of "show packet"; another common example is to use
       "config t" in place of "configure terminal". For readability,
       this manual will continue with the full commands.

       First try out the show command:

         mz# show ?

       mausezahn maintains its own ARP table and observes anomalies.
       There is an entry for every physical interface (however this host
       has only one):

         mz# show arp
         Intf    Index     IP address     MAC address       last
       Ch  UCast BCast Info
         eth0    [1] D  00:09:5b:9a:15:84  23:44:41
       1     1     0  0000

       The column Ch tells us that the announced MAC address has only
       changed one time (= when it was learned). The columns Ucast and
       BCast tell us how often this entry was announced via unicast or
       broadcast respectively.

       Let's check our interfaces:

         mz# show interface
         Available network interfaces:
                        real             real                  used
       (fake)      used (fake)
          device        IPv4 address     MAC address           IPv4
       address     MAC address
         > eth0      00:30:05:76:2e:8d      00:30:05:76:2e:8d
           lo         00:00:00:00:00:00
         2 interfaces found.
         Default interface is eth0.

   Defining packets:
       Let's check the current packet list:

         mz# show packet
         Packet layer flags: E=Ethernet, S=SNAP, Q=802.1Q, M=MPLS,
       I/i=IP/delivery_off, U=UDP, T=TCP
         PktID  PktName           Layers  Proto    Size  State
       Device      Delay       Count/CntX
             1  sysARP_servic...  E-----  ARP        60  config     lo
       100 msec        1/0 (100%)
         1 packets defined, 0 active.

       We notice that there is already one system-defined packet
       process; it has been created and used only once (during startup)
       by mausezahn's ARP service.  Currently, its state is config which
       means that the process is sleeping.

   General packet options:
       Now let's create our own packet process and switch into the
       global configuration mode:

         mz# configure terminal
         mz(config)# packet
         Allocated new packet PKT0002 at slot 2
         mz(config-pkt-2)# ?
         name                 Assign a unique name
         description          Assign a packet description text
         bind                 Select the network interface
         count                Configure the packet count value
         delay                Configure the inter-packet delay
         interval             Configure a greater interval
         type                 Specify packet type
         mac                  Configure packet's MAC addresses
         tag                  Configure tags
         payload              Configure a payload
         port                 Configure packet's port numbers
         end                  End packet configuration mode
         ethernet             Configure frame's Ethernet, 802.2, 802.3,
       or SNAP settings
         ip                   Configure packet's IP settings
         udp                  Configure packet's UDP header parameters
         tcp                  Configure packet's TCP header parameters

       Here are a lot of options but normally you only need a few of
       them. When you configure lots of different packets you might
       assign a reasonable name and description for them:

         mz(config-pkt-2)# name Test
         mz(config-pkt-2)# description This is just a test

       You can, for example, change the default settings for the source
       and destination MAC or IP addresses using the mac and ip

         mz(config-pkt-2)# ip address destination /24
         mz(config-pkt-2)# ip address source random

       In the example above, we configured a range of addresses (all
       hosts in the network should be addressed). Additionally
       we spoof our source IP address. Of course, we can also add one or
       more VLAN and, or, MPLS tag(s):

         mz(config-pkt-2)# tag ?
         dot1q                Configure 802.1Q (and 802.1P) parameters
         mpls                 Configure MPLS label stack
         mz(config-pkt-2)# tag dot ?
         Configure 802.1Q tags:
         VLAN[:CoS] [VLAN[:CoS]] ...   The leftmost tag is the outer tag
       in the frame
         remove <tag-nr> | all         Remove one or more tags (<tag-nr>
       starts with 1),
                                       by default the first
       (=leftmost,outer) tag is removed,
                                       keyword 'all' can be used instead
       of tag numbers.
         cfi | nocfi [<tag-nr>]        Set or unset the CFI-bit in any
       tag (by default
                                       assuming the first tag).
         mz(config-pkt-2)# tag dot 1:7 200:5

   Configure count and delay:
         mz(config-pkt-2)# count 1000
         mz(config-pkt-2)# delay ?
         delay <value> [hour | min | sec | msec | usec | nsec]

       Specify the inter-packet delay in hours, minutes, seconds,
       milliseconds, microseconds or nanoseconds. The default unit is
       milliseconds (i.e. when no unit is given).

         mz(config-pkt-2)# delay 1 msec
         Inter-packet delay set to 0 sec and 1000000 nsec

   Configuring protocol types:
       mausezahn's interactive mode supports a growing list of protocols
       and only relies on the MOPS architecture (and not on libnet as is
       the case with the legacy direct mode):

         mz(config-pkt-2)# type
         Specify a packet type from the following list:
         mz(config-pkt-2)# type tcp
         seqnr                Configure the TCP sequence number
         acknr                Configure the TCP acknowledgement number
         hlen                 Configure the TCP header length
         reserved             Configure the TCP reserved field
         flags                Configure a combination of TCP flags at
         cwr                  Set or unset the TCP CWR flag
         ece                  Set or unset the TCP ECE flag
         urg                  Set or unset the TCP URG flag
         ack                  set or unset the TCP ACK flag
         psh                  set or unset the TCP PSH flag
         rst                  set or unset the TCP RST flag
         syn                  set or unset the TCP SYN flag
         fin                  set or unset the TCP FIN flag
         window               Configure the TCP window size
         checksum             Configure the TCP checksum
         urgent-pointer       Configure the TCP urgent pointer
         options              Configure TCP options
         end                  End TCP configuration mode
         mz(config-pkt-2-tcp)# flags syn fin rst
         Current setting is: --------------------RST-SYN-FIN
         mz(config-pkt-2-tcp)# end
         mz(config-pkt-2)# payload ascii This is a dummy payload for my
       first packet
         mz(config-pkt-2)# end

       Now configure another packet, for example let's assume we want an
       LLDP process:

         mz(config)# packet
         Allocated new packet PKT0003 at slot 3
         mz(config-pkt-3)# type lldp
         mz(config-pkt-3-lldp)# exit
         mz(config)# exit

       In the above example we only use the default LLDP settings and
       don't configure further LLDP options or TLVs. Back in the top
       level of the CLI let's verify what we had done:

         mz# show packet
         Packet layer flags: E=Ethernet, S=SNAP, Q=802.1Q, M=MPLS,
       I/i=IP/delivery_off, U=UDP, T=TCP
         PktID  PktName            Layers  Proto    Size  State
       Device   Delay      Count/CntX
            1   sysARP_servic...   E-----  ARP        60  config     lo
       100 msec       1/0 (100%)
            2   Test               E-Q-IT            125  config
       eth0    1000 usec    1000/1000 (0%)
            3   PKT0003            E-----  LLDP       36  config
       eth0      30 sec        0/0 (0%)
         3 packets defined, 0 active.

       The column Layers indicates which major protocols have been
       combined. For example the packet with packet-id 2 ("Test")
       utilizes Ethernet (E), IP (I), and TCP (T). Additionally an
       802.1Q tag (Q) has been inserted. Now start one of these packet

         mz# start slot 3
         Activate [3]
         mz# show packet
         Packet layer flags: E=Ethernet, S=SNAP, Q=802.1Q, M=MPLS,
       I/i=IP/delivery_off, U=UDP, T=TCP
         PktID  PktName            Layers  Proto    Size  State
       Device   Delay      Count/CntX
            1   sysARP_servic...   E-----  ARP        60  config     lo
       100 msec       1/0 (100%)
            2   Test               E-Q-IT            125  config
       eth0    1000 usec    1000/1000 (0%)
            3   PKT0003            E-----  LLDP       36  config
       eth0      30 sec        0/1 (0%)
         3 packets defined, 1 active.

       Let's have a more detailed look at a specific packet process:

         mz# show packet 2
         Packet [2] Test
         Description: This is just a test
         State: config, Count=1000, delay=1000 usec (0 s 1000000 nsec),
       interval= (undefined)
          Ethernet: 00-30-05-76-2e-8d => ff-ff-ff-ff-ff-ff  [0800 after
       802.1Q tag]
          Auto-delivery is ON (that is, the actual MAC is adapted upon
          802.1Q: 0 tag(s);  (VLAN:CoS)
          IP:  SA= (not random) (no range)
               DA= (no range)
               ToS=0x00  proto=17  TTL=255  ID=0  offset=0  flags: -|-|-
               len=49664(correct)  checksum=0x2e8d(correct)
          TCP: 83 bytes segment size (including TCP header)
               SP=0 (norange) (not random), DP=0 (norange) (not random)
               SQNR=3405691582 (start 0, stop 4294967295, delta 0) --
       ACKNR=0 (invalid)
               Flags: ------------------------SYN----, reserved field is
       00, urgent pointer= 0
               Announced window size= 100
               Offset= 0 (times 32 bit; value is valid), checksum= ffff
               (No TCP options attached) - 0 bytes defined
          Payload size: 43 bytes
          Frame size: 125 bytes
           1  ff:ff:ff:ff:ff:ff:00:30  05:76:2e:8d:81:00:e0:01
       81:00:a0:c8:08:00:45:00  00:67:00:00:00:00:ff:06
          33  fa:e4:c0:a8:00:04:ff:ff  ff:ff:00:00:00:00:ca:fe
       ba:be:00:00:00:00:a0:07  00:64:f7:ab:00:00:02:04
          65  05:ac:04:02:08:0a:19:35  90:c3:00:00:00:00:01:03
       03:05:54:68:69:73:20:69  73:20:61:20:64:75:6d:6d
          97  79:20:70:61:79:6c:6f:61  64:20:66:6f:72:20:6d:79
       20:66:69:72:73:74:20:70  61:63:6b:65:74

       If you want to stop one or more packet processes, use the stop
       command. The "emergency stop" is when you use stop all:

         mz# stop all
         [3] PKT0003
         Stopped 1 transmission processe(s)

       The launch command provides a shortcut for commonly used packet
       processes. For example to behave like a STP-capable bridge we
       want to start an BPDU process with typical parameters:

         mz# launch bpdu
         Allocated new packet sysBPDU at slot 5
         mz# show packet
         Packet layer flags: E=Ethernet, S=SNAP, Q=802.1Q, M=MPLS,
       I/i=IP/delivery_off, U=UDP, T=TCP
         PktID  PktName           Layers  Proto    Size  State
       Device      Delay       Count/CntX
             1  sysARP_servic...  E-----  ARP        60  config     lo
       100 msec        1/0 (100%)
             2  Test              E-Q-IT            125  config     eth0
       1000 usec     1000/1000 (0%)
             3  PKT0003           E-----  LLDP       36  config     eth0
       30 sec        0/12 (0%)
             4  PKT0004           E---I-  IGMP       46  config     eth0
       100 msec        0/0 (0%)
             5  sysBPDU           ES----  BPDU       29  active     eth0
       2 sec        0/1 (0%)
         5 packets defined, 1 active.

       Now a Configuration BPDU is sent every 2 seconds, claiming to be
       the root bridge (and usually confusing the LAN. Note that only
       packet 5 (i.e. the last row) is active and therefore sending
       packets while all other packets are in state config (i.e. they
       have been configured but they are not doing anything at the

   Configuring a greater interval:
       Sometimes you may want to send a burst of packets at a greater

         mz(config)# packet 2
         Modify packet parameters for packet Test [2]
         mz(config-pkt-2)# interval
         Configure a greater packet interval in days, hours, minutes, or
         Arguments: <value>  <days | hours | minutes | seconds>
         Use a zero value to disable an interval.
         mz(config-pkt-2)# interval 1 hour
         mz(config-pkt-2)# count 10
         mz(config-pkt-2)# delay 15 usec
         Inter-packet delay set to 0 sec and 15000 nsec

       Now this packet is sent ten times with an inter-packet delay of
       15 microseconds and this is repeated every hour. When you look at
       the packet list, an interval is indicated with the additional
       flag 'i' when inactive or 'I' when active:

         mz# show packet
         Packet layer flags: E=Ethernet, S=SNAP, Q=802.1Q, M=MPLS,
       I/i=IP/delivery_off, U=UDP, T=TCP
         PktID  PktName           Layers  Proto    Size  State
       Device      Delay       Count/CntX
             1  sysARP_servic...  E-----  ARP        60  config     lo
       100 msec        1/0 (100%)
             2  Test              E-Q-IT            125  config-i   eth0
       15 usec       10/10 (0%)
             3  PKT0003           E-----  LLDP       36  config     eth0
       30 sec        0/12 (0%)
             4  PKT0004           E---I-  IGMP       46  config     eth0
       100 msec        0/0 (0%)
             5  sysBPDU           ES----  BPDU       29  active     eth0
       2 sec        0/251 (0%)
         5 packets defined, 1 active.
         mz# start slot 2
         Activate [2]
         mz# show packet
         Packet layer flags: E=Ethernet, S=SNAP, Q=802.1Q, M=MPLS,
       I/i=IP/delivery_off, U=UDP, T=TCP
         PktID  PktName           Layers  Proto    Size  State
       Device      Delay       Count/CntX
             1  sysARP_servic...  E-----  ARP        60  config     lo
       100 msec        1/0 (100%)
             2  Test              E-Q-IT            125  config+I   eth0
       15 usec       10/0 (100%)
             3  PKT0003           E-----  LLDP       36  config     eth0
       30 sec        0/12 (0%)
             4  PKT0004           E---I-  IGMP       46  config     eth0
       100 msec        0/0 (0%)
             5  sysBPDU           ES----  BPDU       29  active     eth0
       2 sec        0/256 (0%)
         5 packets defined, 1 active.

       Note that the flag 'I' indicates that an interval has been
       specified for packet 2. The process is not active at the moment
       (only packet 5 is active here) but it will become active at a
       regular interval. You can verify the actual interval when viewing
       the packet details via the 'show packet 2' command.

   Load prepared configurations:
       You can prepare packet configurations using the same commands as
       you would type them in on the CLI and then load them to the CLI.
       For example, assume we have prepared a file 'test.mops'

         configure terminal
         name IGMP_TEST
         desc This is only a demonstration how to load a file to mops
         type igmp

       Then we can add this packet configuration to our packet list
       using the load command:

         mz# load test.mops
         Read commands from test.mops...
         Allocated new packet PKT0002 at slot 2
         mz# show packet
         Packet layer flags: E=Ethernet, S=SNAP, Q=802.1Q, M=MPLS,
       I/i=IP/delivery_off, U=UDP, T=TCP
         PktID  PktName           Layers  Proto    Size  State
       Device      Delay       Count/CntX
             1  sysARP_servic...  E-----  ARP        60  config     lo
       100 msec        1/0 (100%)
             2  IGMP_TEST         E---I-  IGMP       46  config     eth0
       100 msec        0/0 (0%)
         2 packets defined, 0 active.

       The file src/examples/mausezahn/example_lldp.conf contains
       another example list of commands to create a bogus LLDP packet.
       You can load this configuration from the mausezahn command line
       as follows:

         mz# load /home/hh/tmp/example_lldp.conf

       In case you copied the file in that path. Now when you enter
       'show packet' you will see a new packet entry in the packet list.
       Use the 'start slot <nr>' command to activate this packet.

       You can store your own packet creations in such a file and easily
       load them when you need them. Every command within such
       configuration files is executed on the command line interface as
       if you had typed it in -- so be careful about the order and don't
       forget to use 'configure terminal' as first command.

       You can even load other files from within a central config file.


   How to specify hexadecimal digits:
       Many arguments allow direct byte input. Bytes are represented as
       two hexadecimal digits. Multiple bytes must be separated either
       by spaces, colons, or dashes - whichever you prefer. The
       following byte strings are equivalent:

         "aa:bb cc-dd-ee ff 01 02 03-04 05"
         "aa bb cc dd ee ff:01:02:03:04 05"

       To begin with, you may want to send an arbitrary fancy (possibly
       invalid) frame right through your network card:

         mausezahn ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:08:00:ca:fe:ba:be

        or equivalent but more readable:

         mausezahn ff:ff:ff:ff:ff:ff-ff:ff:ff:ff:ff:ff-08:00-ca:fe:ba:be

   Basic operations:
       All major command line options are listed when you execute
       mausezahn without arguments. For practical usage, keep the
       following special (not so widely known) options in mind:

         -r                    Multiplies the specified delay with a
       random value.
         -p <length>           Pad the raw frame to specified length
       (using random bytes).
         -P <ASCII Payload>    Use the specified ASCII payload.
         -f <filename>         Read the ASCII payload from a file.
         -F <filename>         Read the hexadecimal payload from a file.
         -S                    Simulation mode: DOES NOT put anything on
       the wire.
                               This is typically combined with one of
       the verbose
                               modes (-v or V).

       Many options require a keyword or a number but the -t option is
       an exception since it requires both a packet type (such as ip,
       udp, dns, etc) and an argument string which is specific for that
       packet type. Here are some simple examples:

         mausezahn -t help
         mausezahn -t tcp help
         mausezahn eth3 -t udp sp=69,dp=69,p=ca:fe:ba:be

       Note: Don't forget that on the CLI the Linux shell (usually the
       Bash) interprets spaces as a delimiting character. That is, if
       you are specifying an argument that consists of multiple words
       with spaces in between, you MUST group these within quotes. For
       example, instead of

         mausezahn eth0 -t udp sp=1,dp=80,p=00:11:22:33

        you could either omit the spaces

         mausezahn eth0 -t udp sp=1,dp=80,p=00:11:22:33

        or, for greater safety, use quotes:

         mausezahn eth0 -t udp "sp=1,dp=80,p=00:11:22:33"

       In order to monitor what's going on, you can enable the verbose
       mode using the -v option. The opposite is the quiet mode (-q)
       which will keep mausezahn absolutely quiet (except for error
       messages and warnings.)

       Don't confuse the payload argument p=... with the padding option
       -p. The latter is used outside the quotes!

   The automatic packet builder:
       An important argument is -t which invokes a packet builder.
       Currently there are packet builders for ARP, BPDU, CDP, IP,
       partly ICMP, UDP, TCP, RTP, DNS, and SYSLOG. (Additionally you
       can insert a VLAN tag or a MPLS label stack but this works
       independently of the packet builder.)

       You get context specific help for every packet builder using the
       help keyword, such as:

         mausezahn -t bpdu help
         mausezahn -t tcp help

       For every packet you may specify an optional payload. This can be
       done either via hexadecimal notation using the payload (or short
       p) argument or directly as ASCII text using the -P option:

         mausezahn eth0 -t ip -P "Hello World"                        #
       ASCII payload
         mausezahn eth0 -t ip p=68:65:6c:6c:6f:20:77:6f:72:6c:64       #
       hex payload
         mausezahn eth0 -t ip "proto=89,                           \
                               p=68:65:6c:6c:6f:20:77:6f:72:6c:64, \   #
       same with other
       # IP arguments

       Note: The raw link access mode only accepts hexadecimal payloads
       (because you specify everything in hexadecimal here.)

   Packet count and delay:
       By default only one packet is sent. If you want to send more
       packets then use the count option -c <count>. When count is zero
       then mausezahn will send forever. By default, mausezahn sends at
       maximum speed (and this is really fast ;-)). If you don't want to
       overwhelm your network devices or have other reasons to send at a
       slower rate then you might want to specify a delay using the -d
       <delay> option.

       If you only specify a numeric value it is interpreted in
       microsecond units.  Alternatively, for easier use, you might
       specify units such as seconds, sec, milliseconds, or msec. (You
       can also abbreviate this with s or m.)  Note: Don't use spaces
       between the value and the unit! Here are typical examples:

       Send an infinite number of frames as fast as possible:

         mausezahn -c 0  "aa bb cc dd ...."

       Send 100,000 frames with a 50 msec interval:

         mausezahn -c 100000 -d 50msec "aa bb cc dd ...."

       Send an unlimited number of BPDU frames in a 2 second interval:

         mausezahn -c 0 -d 2s -t bpdu conf

       Note: mausezahn does not support fractional numbers. If you want
       to specify for example 2.5 seconds then express this in
       milliseconds (2500 msec).

   Source and destination addresses:
       As a mnemonic trick keep in mind that all packets run from "A" to
       "B". You can always specify source and destination MAC addresses
       using the -a and -b options, respectively. These options also
       allow keywords such as rand, own, bpdu, cisco, and others.

       Similarly, you can specify source and destination IP addresses
       using the -A and -B options, respectively. These options also
       support FQDNs (i.e. domain names) and ranges such as or Additionally, the source
       address option supports the rand keyword (ideal for "attacks").

       Note: When you use the packet builder for IP-based packets (e.g.
       UDP or TCP) then mausezahn automatically cares about correct MAC
       and IP addresses (i.e.  it performs ARP, DHCP, and DNS for you).
       But when you specify at least a single link-layer address (or any
       other L2 option such as a VLAN tag or MPLS header) then ARP is
       disabled and you must care for the Ethernet destination address
       for yourself.

   `-- Direct link access:
       mausezahn allows you to send ANY chain of bytes directly through
       your Ethernet interface:

         mausezahn eth0 "ff:ff:ff:ff:ff:ff ff:ff:ff:ff:ff:ff 00:00

       This way you can craft every packet you want but you must do it
       by hand. Note: On Wi-Fi interfaces the header is much more
       complicated and automatically created by the Wi-Fi driver. As an
       example to introduce some interesting options, lets continuously
       send frames at max speed with random source MAC address and
       broadcast destination address, additionally pad the frame to 1000

         mausezahn eth0 -c 0 -a rand -b bcast -p 1000 "08 00 aa bb cc

       The direct link access supports automatic padding using the -p
       <total frame length> option. This allows you to pad a raw L2
       frame to the desired length.  You must specify the total length,
       and the total frame length must have at least 15 bytes for
       technical reasons. Zero bytes are used for padding.

   `-- ARP:
       mausezahn provides a simple interface to the ARP packet. You can
       specify the ARP method (request|reply) and up to four arguments:
       sendermac, targetmac, senderip, targetip, or short smac, tmac,
       sip, tip. By default, an ARP reply is sent with your own
       interface addresses as source MAC and IP address, and a broadcast
       destination MAC and IP address. Send a gratuitous ARP request (as
       used for duplicate IP address detection):

         mausezahn eth0 -t arp

       ARP cache poisoning:

         mausezahn eth0 -t arp "reply, senderip=,
       targetmac=00:00:0c:01:02:03, \

        where by default your interface MAC address will be used as
       sendermac, senderip denotes the spoofed IP address, targetmac and
       targetip identifies the receiver. By default, the Ethernet source
       address is your interface MAC and the destination address is the
       broadcast address. You can change this using the flags -a and -b.

   `-- BPDU:
       mausezahn provides a simple interface to the 802.1D BPDU frame
       format (used to create the Spanning Tree in bridged networks). By
       default, standard IEEE 802.1D BPDUs are sent and it is assumed
       that your computer wants to become the root bridge (rid=bid).
       Optionally the 802.3 destination address can be a specified MAC
       address, broadcast, own MAC, or Cisco's PVST+ MAC address. The
       destination MAC can be specified using the -b command which,
       besides MAC addresses, accepts keywords such as bcast, own, pvst,
       or stp (default). PVST+ is supported as well. Simply specify the
       VLAN for which you want to send a BPDU:

         mausezahn eth0 -t bpdu "vlan=123, rid=2000"

       See mausezahn -t bpdu help for more details.

   `-- CDP:
       mausezahn can send Cisco Discovery Protocol (CDP) messages since
       this protocol has security relevance. Of course lots of dirty
       tricks are possible; for example arbitrary TLVs can be created
       (using the hex-payload argument for example
       p=00:0e:00:07:01:01:90) and if you want to stress the CDP
       database of some device, mausezahn can send each CDP message with
       another system-id using the change keyword:

         mausezahn -t cdp change -c 0

       Some routers and switches may run into deep problems ;-) See
       mausezahn -t cdp help for more details.

   `-- 802.1Q VLAN Tags:
       mausezahn allows simple VLAN tagging for IP (and other higher
       layer) packets.  Simply use the option -Q <[CoS:]VLAN>, such as
       -Q 10 or -Q 3:921. By default CoS=0. For example send a TCP
       packet in VLAN 500 using CoS=7:

         mausezahn eth0 -t tcp -Q 7:500 "dp=80, flags=rst, p=aa:aa:aa"

       You can create as many VLAN tags as you want! This is interesting
       to create QinQ encapsulations or VLAN hopping: Send a UDP packet
       with VLAN tags 100 (outer) and 651 (inner):

         mausezahn eth0 -t udp "dp=8888, sp=13442" -P "Mausezahn is
       great" -Q 100,651

       Don't know if this is useful anywhere but at least it is

         mausezahn eth0 -t udp "dp=8888, sp=13442" -P "Mausezahn is
       great"  \
                        -Q 6:5,7:732,5:331,5,6

       Mix it with MPLS:

         mausezahn eth0 -t udp "dp=8888, sp=13442" -P "Mausezahn is
       great" -Q 100,651 -M 314

       When in raw Layer 2 mode you must create the VLAN tag completely
       by yourself.  For example if you want to send a frame in VLAN 5
       using CoS 0 simply specify 81:00 as type field and for the next
       two bytes the CoS (PCP), DEI (CFI), and VLAN ID values (all
       together known as TCI):

         mausezahn eth0 -b bc -a rand "81:00 00:05 08:00 aa-aa-aa-aa-aa-

   `-- MPLS labels:
       mausezahn allows you to insert one or more MPLS headers. Simply
       use the option -M <label:CoS:TTL:BoS> where only the label is
       mandatory. If you specify a second number it is interpreted as
       the experimental bits (the CoS usually). If you specify a third
       number it is interpreted as TTL. By default the TTL is set to
       255. The Bottom of Stack flag is set automatically, otherwise the
       frame would be invalid, but if you want you can also set or unset
       it using the S (set) and s (unset) argument. Note that the BoS
       must be the last argument in each MPLS header definition. Here
       are some examples:

       Use MPLS label 214:

         mausezahn eth0 -M 214 -t tcp "dp=80" -P "HTTP..." -B

       Use three labels (the 214 is now the outer):

         mausezahn eth0 -M 9999,51,214 -t tcp "dp=80" -P "HTTP..." -B

       Use two labels, one with CoS=5 and TTL=1, the other with CoS=7:

         mausezahn eth0 -M 100:5:1,500:7 -t tcp "dp=80" -P "HTTP..." -B

       Unset the BoS flag (which will result in an invalid frame):

         mausezahn eth0 -M 214:s -t tcp "dp=80" -P "HTTP..." -B

   Layer 3-7:
       IP, UDP, and TCP packets can be padded using the -p option.
       Currently 0x42 is used as padding byte ('the answer'). You cannot
       pad DNS packets (would be useless anyway).

   `-- IP:
       mausezahn allows you to send any malformed or correct IP packet.
       Every field in the IP header can be manipulated. The IP addresses
       can be specified via the -A and -B options, denoting the source
       and destination address, respectively. You can also specify an
       address range or a host name (FQDN).  Additionally, the source
       address can also be random. By default the source address is your
       interface IP address and the destination address is a broadcast
       address. Here are some examples:

       ASCII payload:

         mausezahn eth0 -t ip -A rand -B  -P "hello

       Hexadecimal payload:

         mausezahn eth0 -t ip -A -B p=ca:fe:ba:be

       Will use correct source IP address:

         mausezahn eth0 -t ip -B

       The Type of Service (ToS) byte can either be specified directly
       by two hexadecimal digits, which means you can also easily set
       the Explicit Congestion Notification (ECN) bits (LSB 1 and 2), or
       you may only want to specify a common DSCP value (bits 3-8) using
       a decimal number (0..63):

       Packet sent with DSCP = Expedited Forwarding (EF):

         mausezahn eth0 -t ip

       If you leave the checksum as zero (or unspecified) the correct
       checksum will be automatically computed. Note that you can only
       use a wrong checksum when you also specify at least one L2 field

   `-- UDP:
       mausezahn supports easy UDP datagram generation. Simply specify
       the destination address (-B option) and optionally an arbitrary
       source address (-A option) and as arguments you may specify the
       port numbers using the dp (destination port) and sp (source port)
       arguments and a payload. You can also easily specify a whole port
       range which will result in sending multiple packets. Here are
       some examples:

       Send test packets to the RTP port range:

         mausezahn eth0 -B -t udp "dp=16384-32767, \

       Send a DNS request as local broadcast (often a local router

         mausezahn eth0 -t udp

       Additionally you may specify the length and checksum using the
       len and sum arguments (will be set correctly by default). Note:
       several protocols have same arguments such as len (length) and
       sum (checksum). If you specified a UDP type packet (via -t udp)
       and want to modify the IP length, then use the alternate keyword
       iplen and ipsum. Also note that you must specify at least one L2
       field which tells mausezahn to build everything without the help
       of your kernel (the kernel would not allow modifying the IP
       checksum and the IP length).

   `-- ICMP:
       mausezahn currently only supports the following ICMP methods:
       PING (echo request), Redirect (various types), Unreachable
       (various types). Additional ICMP types will be supported in
       future. Currently you would need to tailor them by yourself, e.g.
       using the IP packet builder (setting proto=1). Use the mausezahn
       -t icmp help for help on currently implemented options.

   `-- TCP:
       mausezahn allows you to easily tailor any TCP packet. Similarly
       as with UDP you can specify source and destination port (ranges)
       using the sp and dp arguments.  Then you can directly specify the
       desired flags using an "|" as delimiter if you want to specify
       multiple flags. For example, a SYN-Flood attack against host using a random source IP address and periodically using
       all 1023 well-known ports could be created via:

         mausezahn eth0 -A rand -B -c 0 -t tcp "dp=1-1023,
       flags=syn"  \
                        -P "Good morning! This is a SYN Flood Attack.
                            We apologize for any inconvenience."

       Be careful with such SYN floods and only use them for firewall
       testing. Check your legal position! Remember that a host with an
       open TCP session only accepts packets with correct socket
       information (addresses and ports) and a valid TCP sequence number
       (SQNR). If you want to try a DoS attack by sending a RST-flood
       and you do NOT know the target's initial SQNR (which is normally
       the case) then you may want to sweep through a range of sequence

         mausezahn eth0 -A -B \
                        -t tcp "sp=80,dp=80,s=1-4294967295"

       Fortunately, the SQNR must match the target host's
       acknowledgement number plus the announced window size. Since the
       typical window size is something between 40000 and 65535 you are
       MUCH quicker when using an increment via the ds argument:

         mausezahn eth0 -A -B \
                        -t tcp "sp=80, dp=80, s=1-4294967295, ds=40000"

       In the latter case mausezahn will only send 107375 packets
       instead of 4294967295 (which results in a duration of
       approximately 1 second compared to 11 hours!). Of course you can
       tailor any TCP packet you like. As with other L4 protocols
       mausezahn builds a correct IP header but you can additionally
       access every field in the IP packet (also in the Ethernet frame).

   `-- DNS:
       mausezahn supports UDP-based DNS requests or responses. Typically
       you may want to send a query or an answer. As usual, you can
       modify every flag in the header.  Here is an example of a simple

         mausezahn eth0 -B -t dns ""

       You can also create server-type messages:

         mausezahn eth0 -A -B \
                        ", a="

       The syntax according to the online help (-t dns help) is:

         query|q = <name>[:<type>]  ............. where type is per
       default "A"
                                                  (and class is always
         answer|a = [<type>:<ttl>:]<rdata> ...... ttl is per default 0.
                  = [<type>:<ttl>:]<rdata>/[<type>:<ttl>:]<rdata>/...

       Note: If you only use the 'query' option then a query is sent. If
       you additionally add an 'answer' then an answer is sent.

         q =
         q =, a=
         q =, a=A:3600:
         q =,

       Please try out mausezahn -t dns help to see the many other
       optional command line options.

   `-- RTP and VoIP path measurements:
       mausezahn can send arbitrary Real Time Protocol (RTP) packets. By
       default a classical G.711 codec packet of 20 ms segment size and
       160 bytes is assumed. You can measure jitter, packet loss, and
       reordering along a path between two hosts running mausezahn. The
       jitter measurement is either done following the variance low-pass
       filtered estimation specified in RFC 3550 or using an alternative
       "real-time" method which is even more precise (the RFC-method is
       used by default). For example on Host1 you start a transmission

         mausezahn -t rtp -B

       And on Host2 ( a receiving process which performs
       the measurement:

         mausezahn -T rtp

       Note that the option flag with the capital "T" means that it is a
       server RTP process, waiting for incoming RTP packets from any
       mausezahn source. In case you want to restrict the measurement to
       a specific source or you want to perform a bidirectional
       measurement, you must specify a stream identifier.  Here is an
       example for bidirectional measurements which logs the running
       jitter average in a file:

         Host1# mausezahn -t rtp id=11:11:11:11 -B &
         Host1# mausezahn -T rtp id=22:22:22:22 "log, path=/tmp/mz/"

         Host2# mausezahn -t rtp id=22:22:22:22 -B &
         Host2# mausezahn -T rtp id=11:11:11:11 "log, path=/tmp/mz/"

       In any case the measurements are printed continuously onto the
       screen; by default it looks like this:

         0.00                     0.19                      0.38
       0.07 msec
       0.14 msec
       0.02 msec
       0.02 msec
       0.07 msec
       0.03 msec
       0.07 msec
       0.10 msec
       0.02 msec
       0.31 msec
       0.07 msec
       0.33 msec
       0.11 msec
       0.07 msec
       0.11 msec
       0.42 msec
       0.04 msec

       More information is shown using the txt keyword:

         mausezahn -T rtp txt
         Got 100 packets from host 0 lost (0 absolute
       lost), 1 out of order
           Jitter_RFC (low pass filtered) = 30 usec
           Samples jitter (min/avg/max)   = 1/186/2527 usec
           Delta-RX (min/avg/max)         = 2010/20167/24805 usec
         Got 100 packets from host 0 lost (0 absolute
       lost), 1 out of order
           Jitter_RFC (low pass filtered) = 17 usec
           Samples jitter (min/avg/max)   = 1/53/192 usec
           Delta-RX (min/avg/max)         = 20001/20376/20574 usec
         Got 100 packets from host 0 lost (0 absolute
       lost), 1 out of order
           Jitter_RFC (low pass filtered) = 120 usec
           Samples jitter (min/avg/max)   = 0/91/1683 usec
           Delta-RX (min/avg/max)         = 18673/20378/24822 usec

       See mausezahn -t rtp help and mz -T rtp help for more details.

   `-- Syslog:
       The traditional Syslog protocol is widely used even in
       professional networks and is sometimes vulnerable. For example
       you might insert forged Syslog messages by spoofing your source
       address (e.g. impersonate the address of a legit network device):

         mausezahn -t syslog sev=3 -P "You have been mausezahned." -A -B

       See mausezahn -t syslog help for more details.

NOTE         top

       When multiple ranges are specified, e.g. destination port ranges
       and destination address ranges, then all possible combinations of
       ports and addresses are used for packet generation. Furthermore,
       this can be mixed with other ranges e.g. a TCP sequence number
       range. Note that combining ranges can lead to a very huge number
       of frames to be sent. As a rule of thumb you can assume that
       about 100,000 frames and more are sent in a fraction of one
       second, depending on your network interface.

       mausezahn has been designed as a fast traffic generator so you
       might easily overwhelm a LAN segment with myriads of packets. And
       because mausezahn could also support security audits it is
       possible to create malicious or invalid packets, SYN floods, port
       and address sweeps, DNS and ARP poisoning, etc.

       Therefore, don't use this tool when you are not aware of the
       possible consequences or have only a little knowledge about
       networks and data communication. If you abuse mausezahn for
       'unallowed' attacks and get caught, or damage something of your
       own, then this is completely your fault. So the safest solution
       is to try it out in a lab environment.

       Also have a look at the netsniff-ng(8) note section on how you
       can properly setup and tune your system.

LEGAL         top

       mausezahn is licensed under the GNU GPL version 2.0.

HISTORY         top

       mausezahn was originally written by Herbert Haas. According to
       his website [1], he unfortunately passed away in 2011 thus
       leaving this tool unmaintained.  It has been adopted and
       integrated into the netsniff-ng toolkit and is further being
       maintained and developed from there. Maintainers are Tobias
       Klauser <> and Daniel Borkmann


SEE ALSO         top

       netsniff-ng(8), trafgen(8), ifpps(8), bpfc(8), flowtop(8),
       astraceroute(8), curvetun(8)

AUTHOR         top

       Manpage was written by Herbert Haas and modified by Daniel

COLOPHON         top

       This page is part of the Linux netsniff-ng toolkit project. A
       description of the project, and information about reporting bugs,
       can be found at

COLOPHON         top

       This page is part of the netsniff-ng (a free Linux networking
       toolkit) project.  Information about the project can be found at
       ⟨⟩.  If you have a bug report for this
       manual page, send it to  This page
       was obtained from the project's upstream Git repository
       ⟨⟩ on 2023-12-22.  (At
       that time, the date of the most recent commit that was found in
       the repository was 2023-02-01.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to

Linux                         03 March 2013                 MAUSEZAHN(8)

Pages that refer to this page: astraceroute(8)bpfc(8)curvetun(8)flowtop(8)ifpps(8)netsniff-ng(8)trafgen(8)