Provided by: ettercap-common_0.8.3.1-5_amd64 bug

NAME

       ettercap - multipurpose sniffer/content filter for man in the middle attacks

***** IMPORTANT NOTE ******

       Since  ettercap  NG  (formerly  0.7.0), all the options have been changed. Even the target
       specification has been changed. Please read carefully this man page.

SYNOPSIS

       ettercap [OPTIONS] [TARGET1] [TARGET2]

       If IPv6 is enabled:
       TARGET is in the form MAC/IPs/IPv6/PORTs
       Otherwise,
       TARGET is in the form MAC/IPs/PORTs
       where IPs and PORTs can be ranges (e.g. /192.168.0.1-30,40,50/20,22,25)

DESCRIPTION

       Ettercap was born as a sniffer for switched LAN (and obviously even  "hubbed"  ones),  but
       during  the  development process it has gained more and more features that have changed it
       to a powerful and flexible tool for man-in-the-middle attacks.   It  supports  active  and
       passive  dissection  of many protocols (even ciphered ones) and includes many features for
       network and host analysis (such as OS fingerprint).

       It has two main sniffing options:

       UNIFIED, this method sniffs all the packets that pass on the cable. You can choose to  put
       or  not  the  interface  in  promisc mode (-p option). The packet not directed to the host
       running ettercap will be forwarded automatically using layer 3 routing. So you can  use  a
       mitm attack launched from a different tool and let ettercap modify the packets and forward
       them for you.
       The kernel ip_forwarding is always disabled by ettercap. This is done to prevent a forward
       of  a packet twice (one by ettercap and one by the kernel).  This is an invasive behaviour
       on gateways. So we recommend you to use ettercap on the gateways ONLY with the UNOFFENSIVE
       MODE  ENABLED.  Since  ettercap listens only on one network interface, launching it on the
       gateway in offensive mode will not allow packets to  be  rerouted  back  from  the  second
       interface.

       BRIDGED,  it  uses  two  network  interfaces and forward the traffic from one to the other
       while performing sniffing and content filtering. This sniffing method is totally  stealthy
       since there is no way to find that someone is in the middle on the cable.  You can look at
       this method as a mitm attack at layer 1. You will be in the middle of  the  cable  between
       two  entities.  Don't  use it on gateways or it will transform your gateway into a bridge.
       HINT: you can use the content filtering engine to drop packets that should not pass.  This
       way ettercap will work as an inline IPS ;)

       You  can  also perform man in the middle attacks while using the unified sniffing. You can
       choose the mitm attack that you prefer. The mitm attack module  is  independent  from  the
       sniffing  and filtering process, so you can launch several attacks at the same time or use
       your own tool for the attack. The crucial point is that the  packets  have  to  arrive  to
       ettercap  with the correct mac address and a different ip address (only these packets will
       be forwarded).

       The most relevant ettercap features are:

       SSH1 support : you can sniff User and Pass, and even  the  data  of  an  SSH1  connection.
       ettercap is the first software capable to sniff an SSH connection in FULL-DUPLEX

       SSL  support  :  you  can sniff SSL secured data... a fake certificate is presented to the
       client and the session is decrypted.

       Characters injection in an established connection :  you  can  inject  characters  to  the
       server  (emulating  commands)  or  to  the  client  (emulating  replies)  maintaining  the
       connection alive !!

       Packet filtering/dropping: You can set up a filter script that searches for  a  particular
       string  (even  hex) in the TCP or UDP payload and replace it with yours or drop the entire
       packet. The filtering engine can match any field  of  the  network  protocols  and  modify
       whatever you want (see etterfilter(8)).

       Remote traffic sniffing through tunnels and route mangling: You can play with linux cooked
       interfaces or use  the  integrated  plugin  to  sniff  tunneled  or  route-mangled  remote
       connections and perform mitm attacks on them.

       Plug-ins support : You can create your own plugin using the ettercap's API.

       Password collector for : TELNET, FTP, POP, RLOGIN, SSH1, ICQ, SMB, MySQL, HTTP, NNTP, X11,
       NAPSTER, IRC, RIP, BGP, SOCKS 5, IMAP 4, VNC, LDAP, NFS, SNMP, HALF LIFE,  QUAKE  3,  MSN,
       YMSG (other protocols coming soon...)

       Passive OS fingerprint: you scan passively the lan (without sending any packet) and gather
       detailed info about the hosts in the LAN: Operating System, running services, open  ports,
       IP, mac address and network adapter vendor.

       Kill a connection: from the connections list you can kill all the connections you want

TARGET SPECIFICATION

       There  is  no  concept  of SOURCE nor DEST. The two targets are intended to filter traffic
       coming from one to the other and vice-versa (since the connection is bidirectional).

       TARGET is in the form MAC/IPs/PORTs.
       NOTE: If IPv6 is enabled, TARGET is in the form MAC/IPs/IPv6/PORTs.

       If you want you can omit any of its parts and this will represent an ANY in that part.
       e.g.
       "//80" means ANY mac address, ANY ip and ONLY port 80
       "/10.0.0.1/" means ANY mac address, ONLY ip 10.0.0.1 and ANY port

       MAC must be unique and in the form 00:11:22:33:44:55

       IPs is a range of IP in dotted notation. You can specify range with  the  -  (hyphen)  and
       single  ip  with  ,  (comma).  You  can  also  use  ; (semicolon) to indicate different ip
       addresses.
       e.g.
       "10.0.0.1-5;10.0.1.33" expands into ip 10.0.0.1, 2, 3, 4, 5 and 10.0.1.33

       PORTs is a range of PORTS. You can specify range with the - (hyphen) and single port  with
       , (comma).
       e.g.
       "20-25,80,110" expands into ports 20, 21, 22, 23, 24, 25, 80 and 110

       NOTE:
       you can reverse the matching of the TARGET by adding the -R option to the command line. So
       if you want to sniff ALL the traffic BUT the one coming  or  going  to  10.0.0.1  you  can
       specify "./ettercap -R /10.0.0.1/"

       NOTE:
       TARGETs  are also responsible of the initial scan of the lan. You can use them to restrict
       the scan to only a subset of the hosts in the netmask. The result of the  merging  between
       the  two targets will be scanned. remember that not specifying a target means "no target",
       but specifying "//" means "all the hosts in the subnet".

PRIVILEGES DROPPING

       ettercap needs root privileges to open the Link Layer sockets.  After  the  initialization
       phase,  the  root  privs  are  not  needed  anymore, so ettercap drops them to UID = 65535
       (nobody). Since ettercap has to write (create)  log  files,  it  must  be  executed  in  a
       directory  with  the  right  permissions  (e.g.  /tmp/).  If  you  want to drop privs to a
       different uid, you can export the environment variable EC_UID with the value  of  the  uid
       you  want  to  drop the privs to (e.g.  export EC_UID=500) or set the correct parameter in
       the etter.conf file.

SSL MITM ATTACK

       SSL mitm attack is dependent on TCP traffic redirection  to  a  custom  listener  port  of
       ettercap.  The redir_command_on and redir_command_off configuration variables take care of
       this (see "etter.conf(5)").
       However, when ettercap starts, traffic for any source and any destination targeted for the
       redirectable  services  will  be  redirected  to  ettercap  and  the  SSL  stream  will be
       intercepted.
       This may not be the desired behaviour. Therefore you can adjust the redirect  rules  after
       ettercap has been started using the selected user interface.

       While  performing  the SSL mitm attack, ettercap substitutes the real ssl certificate with
       its own. The fake certificate is created  on  the  fly  and  all  the  fields  are  filled
       according to the real cert presented by the server. Only the issuer is modified and signed
       with the private key contained in the 'etter.ssl.crt' file. If you want to use a different
       private  key  you  have  to  regenerate  this  file.  To  regenerate the cert file use the
       following commands:

       openssl genrsa -out etter.ssl.crt 1024
       openssl req -new -key etter.ssl.crt -out tmp.csr
       openssl x509 -req -days 1825 -in tmp.csr -signkey etter.ssl.crt -out tmp.new
       cat tmp.new >> etter.ssl.crt
       rm -f tmp.new tmp.csr

       NOTE: SSL mitm is not available (for now) in bridged mode.

       NOTE: You can use the --certificate/--private-key long options if you want  to  specify  a
       different file rather than the etter.ssl.crt file.

OPTIONS

       Options  that  make  sense together can generally be combined. ettercap will warn the user
       about unsupported option combinations.

       SNIFFING AND ATTACK OPTIONS

       ettercap NG has a new unified sniffing method. This  implies  that  ip_forwarding  in  the
       kernel  is  always  disabled  and  the  forwarding  is done by ettercap. Every packet with
       destination mac address equal to  the  host's  mac  address  and  destination  ip  address
       different  for the one bound to the iface will be forwarded by ettercap. Before forwarding
       them, ettercap can content filter, sniff, log or drop them. It does not matter  how  these
       packets  are  hijacked,  ettercap will process them. You can even use external programs to
       hijack packet.
       You have full control of what ettercap should receive.  You  can  use  the  internal  mitm
       attacks, set the interface in promisc mode, use plugins or use every method you want.

       IMPORTANT  NOTE: if you run ettercap on a gateway, remember to re-enable the ip_forwarding
       after you have killed ettercap. Since ettercap drops its privileges, it cannot restore the
       ip_forwarding for you.

       -M, --mitm <METHOD:ARGS>
              MITM attack
              This  option will activate the man in the middle attack. The mitm attack is totally
              independent from the sniffing. The aim of the  attack  is  to  hijack  packets  and
              redirect them to ettercap. The sniffing engine will forward them if necessary.
              You  can  choose  the  mitm attack that you prefer and also combine some of them to
              perform different attacks at the same time.
              If a mitm method requires some parameters you can specify  them  after  the  colon.
              (e.g.  -M dhcp:ip_pool,netmask,etc )

              The following mitm attacks are available:

              arp ([remote],[oneway])
                     This  method  implements the ARP poisoning mitm attack. ARP requests/replies
                     are sent to the victims to poison their ARP cache. Once the cache  has  been
                     poisoned  the  victims will send all packets to the attacker which, in turn,
                     can modify and forward them to the real destination.

                     In silent mode (-z option) only the first target is selected, if you want to
                     poison  multiple target in silent mode use the -j option to load a list from
                     a file.

                     You can select empty targets and they will be expanded  as  'ANY'  (all  the
                     hosts in the LAN). The target list is joined with the hosts list (created by
                     the arp scan) and the result is used to determine the victims of the attack.

                     The parameter "remote" is optional and you have to specify it if you want to
                     sniff  remote ip address poisoning a gateway. Indeed if you specify a victim
                     and the gw in the TARGETS, ettercap will sniff only connection between them,
                     but  to enable ettercap to sniff connections that pass thru the gw, you have
                     to use this parameter.

                     The parameter "oneway" will force ettercap to poison only  from  TARGET1  to
                     TARGET2.  Useful  if  you  want to poison only the client and not the router
                     (where an arp watcher can be in place).

                     Example:

                     the targets are: /10.0.0.1-5/ /10.0.0.15-20/
                     and the host list is: 10.0.0.1 10.0.0.3 10.0.0.16 10.0.0.18

                     the associations between the victims will be:
                     1 and 16, 1 and 18, 3 and 16, 3 and 18

                     if the targets overlap each other, the association with identical ip address
                     will be skipped.

                     NOTE:  if  you  manage  to  poison a client, you have to set correct routing
                     table in the kernel specifying the GW. If your routing table  is  incorrect,
                     the poisoned clients will not be able to navigate the Internet.

              icmp (MAC/IP)
                     This  attack  implements  ICMP redirection. It sends a spoofed icmp redirect
                     message to the hosts in  the  lan  pretending  to  be  a  better  route  for
                     internet.  All  connections  to  internet will be redirected to the attacker
                     which, in turn, will forward them to the real gateway. The resulting  attack
                     is a HALF-DUPLEX mitm. Only the client is redirected, since the gateway will
                     not accept redirect messages for a directly connected network.  BE  SURE  TO
                     NOT  USE  FILTERS  THAT  MODIFY  THE PAYLOAD LENGTH. you can use a filter to
                     modify packets, but the length must be the  same  since  the  tcp  sequences
                     cannot be updated in both ways.
                     You  have to pass as argument the MAC and the IP address of the real gateway
                     for the lan.
                     Obviously you have to be able to sniff all the traffic.  If  you  are  on  a
                     switch you have to use a different mitm attack such as arp poisoning.

                     NOTE: to restrict the redirection to a given target, specify it as a TARGET

                     Example:

                     -M icmp:00:11:22:33:44:55/10.0.0.1

                     will redirect all the connections that pass thru that gateway.

              dhcp (ip_pool/netmask/dns)
                     This  attack  implements  DHCP spoofing. It pretends to be a DHCP server and
                     tries to win the race condition with the real one to  force  the  client  to
                     accept  the attacker's reply. This way ettercap is able to manipulate the GW
                     parameter and hijack all the outgoing traffic generated by the clients.
                     The resulting attack is a HALF-DUPLEX mitm. So be sure  to  use  appropriate
                     filters (see above in the ICMP section).

                     You  have  to pass the ip pool to be used, the netmask and the ip of the dns
                     server.  Since ettercap tries to win the race with the real server, it  DOES
                     NOT  CHECK  if the ip is already assigned. You have to specify an ip pool of
                     FREE addresses to be used. The ip pool has  the  same  form  of  the  target
                     specification.

                     If  the client sends a dhcp request (suggesting an ip address) ettercap will
                     ack on that ip and modify only the gw option. If the  client  makes  a  dhcp
                     discovery,  ettercap  will  use  the first unused ip address of the list you
                     have specified on command line. Every discovery consumes an ip address. When
                     the  list  is  over, ettercap stops offering new ip addresses and will reply
                     only to dhcp requests.
                     If you don't want to offer any  ip  address,  but  only  change  the  router
                     information of dhcp request/ack, you can specify an empty ip_pool.

                     BIG WARNING: if you specify a list of ip that are in use, you will mess your
                     network! In general, use this attack carefully. It can  really  mess  things
                     up!   When you stop the attack, all the victims will be still convinced that
                     ettercap is the gateway until the lease expires...

                     Example:

                     -M dhcp:192.168.0.30,35,50-60/255.255.255.0/192.168.0.1
                     reply to DHCP offer and request.

                     -M dhcp:/255.255.255.0/192.168.0.1
                     reply only to DHCP request.

              port ([remote],[tree])
                     This attack implements Port Stealing. This technique is useful to sniff in a
                     switched  environment when ARP poisoning is not effective (for example where
                     static mapped ARPs are used).

                     It floods the LAN (based on port_steal_delay option in etter.conf) with  ARP
                     packets. If you don't specify the "tree" option, the destination MAC address
                     of each "stealing" packet is the same as  the  attacker's  one  (other  NICs
                     won't  see these packets), the source MAC address will be one of the MACs in
                     the host list. This process "steals" the switch port of each victim host  in
                     the host list.  Using low delays, packets destined to "stolen" MAC addresses
                     will be received by the attacker, winning the race condition with  the  real
                     port owner.  When the attacker receives packets for "stolen" hosts, it stops
                     the flooding process and performs an ARP request for the real destination of
                     the  packet.   When  it receives the ARP reply it's sure that the victim has
                     "taken back" his port, so ettercap can re-send the packet to the destination
                     as is.  Now we can re-start the flooding process waiting for new packets.

                     If  you  use the "tree" option, the destination MAC address of each stealing
                     packet will be a bogus one, so these packets will  be  propagated  to  other
                     switches (not only the directly connected one). This way you will be able to
                     steal ports on other switches in the tree (if any), but you will generate  a
                     huge amount of traffic (according to port_steal_delay).  The "remote" option
                     has the same meaning as in "arp" mitm method.

                     When you stop the attack, ettercap will send an ARP request to  each  stolen
                     host giving back their switch ports.
                     You  can  perform  either  HALF  or  FULL  DUPLEX  mitm  according to target
                     selection.

                     NOTE: Use this mitm method only on ethernet switches. Use it  carefully,  it
                     could produce performances loss or general havoc.

                     NOTE:  You  can  NOT use this method in only-mitm mode (-o flag), because it
                     hooks the sniffing engine, and you can't use interactive data injection.

                     NOTE: It could be dangerous  to  use  it  in  conjunction  with  other  mitm
                     methods.

                     NOTE:  This  mitm  method doesn't work on Solaris and Windows because of the
                     lipcap and libnet design and the lack of certain ioctl().  (We will  feature
                     this method on these OSes if someone will request it...)

                     Example:

                     The targets are: /10.0.0.1/ /10.0.0.15/
                     You will intercept and visualize traffic between 10.0.0.1 and 10.0.0.15, but
                     you will receive all the traffic for 10.0.0.1 and 10.0.0.15 too.

                     The target is: /10.0.0.1/
                     You will intercept and visualize all the traffic for 10.0.0.1.

              ndp ([remote],[oneway])
                     NOTE: This MITM method is only supported if IPv6 support has been enabled.

                     This method implements the NDP poisoning attack which is used  for  MITM  of
                     IPv6  connections.  ND  requests/replies  are  sent to the victims to poison
                     their neighbor cache. Once the cache has been poisoned the victims will send
                     all IPv6 packets to the attacker which, in turn, can modify and forward them
                     to the real destination.

                     In silent mode (-z option) only the first target is selected, if you want to
                     poison  multiple target in silent mode use the -j option to load a list from
                     a file.

                     You can select empty targets and they will be expanded  as  'ANY'  (all  the
                     hosts in the LAN). The target list is joined with the hosts list (created by
                     the arp scan) and the result is used to determine the victims of the attack.

                     The parameter "remote" is optional and you have to specify it if you want to
                     sniff  remote ip address poisoning a gateway. Indeed if you specify a victim
                     and the gw in the TARGETS, ettercap will sniff only connection between them,
                     but  to enable ettercap to sniff connections that pass thru the gw, you have
                     to use this parameter.

                     The parameter "oneway" will force ettercap to poison only  from  TARGET1  to
                     TARGET2.  Useful  if  you  want to poison only the client and not the router
                     (where an arp watcher can be in place).

                     Example:

                     Targets are: //fe80::260d:afff:fe6e:f378/ //2001:db8::2:1/
                     Ranges of IPv6 addresses are not yet supported.

                     NOTE: if you manage to poison a client, you  have  to  set  correct  routing
                     table  in  the kernel specifying the GW. If your routing table is incorrect,
                     the poisoned clients will not be able to navigate the Internet.

                     NOTE: in IPv6 usually the link-local address of the router is being used  as
                     the gateway address. Therefore you need to set the link-local address of the
                     router as one target and the global-unicast address of  the  victim  as  the
                     other in order to set up a successful IPv6 MITM attack using NDP poisoning.

       -o, --only-mitm
              This options disables the sniffing thread and enables only the mitm attack.  Useful
              if you want to use ettercap to perform mitm attacks and another  sniffer  (such  as
              wireshark) to sniff the traffic. Keep in mind that the packets are not forwarded by
              ettercap. The kernel will be responsible for the forwarding.  Remember to  activate
              the "ip forwarding" feature in your kernel.

       -f, --pcapfilter <FILTER>
              Set  a  capturing filter in the pcap library. The format is the same as tcpdump(1).
              Remember that this kind of filter will not sniff packets out of the wire, so if you
              want  to  perform  a  mitm  attack,  ettercap  will not be able to forward hijacked
              packets.
              These filters are useful to decrease the network load impact into ettercap decoding
              module.

       -B, --bridge <IFACE>
              BRIDGED sniffing
              You  need  two  network interfaces. ettercap will forward form one to the other all
              the traffic it sees. It is useful for man in the middle at the physical  layer.  It
              is  totally stealthy since it is passive and there is no way for an user to see the
              attacker.
              You can content filter all the traffic as you were  a  transparent  proxy  for  the
              "cable".

       OFF LINE SNIFFING

       -r, --read <FILE>
              OFF LINE sniffing
              With  this  option enabled, ettercap will sniff packets from a pcap compatible file
              instead of capturing from the wire.
              This is useful if you have a file dumped from tcpdump or wireshark and you want  to
              make an analysis (search for passwords or passive fingerprint) on it.
              Obviously  you  cannot  use  "active"  sniffing  (arp  poisoning or bridging) while
              sniffing from a file.

       -w, --write <FILE>
              WRITE packet to a pcap file
              This is useful if you have to use "active" sniffing (arp poison) on a switched  LAN
              but  you  want  to  analyze the packets with tcpdump or wireshark. You can use this
              option to dump the packets  to  a  file  and  then  load  it  into  your  favourite
              application.

              NOTE:  dump  file  collect  ALL  the  packets disregarding the TARGET. This is done
              because you may want to log even protocols not supported by ettercap,  so  you  can
              analyze them with other tools.

              TIP: you can use the -w option in conjunction with the -r one. This way you will be
              able to filter the payload of the dumped  packets  or  decrypt  WEP-encrypted  WiFi
              traffic and dump them to another file.

       USER INTERFACES OPTIONS

       -T, --text
              The text only interface, only printf ;)
              It is quite interactive, press 'h' in every moment to get help on what you can do.

       -q, --quiet
              Quiet  mode. It can be used only in conjunction with the console interface. It does
              not print packet content. It is useful if you want to convert pcap file to ettercap
              log files.

              example:

              ettercap -Tq -L dumpfile -r pcapfile

       -s, --script <COMMANDS>
              With  this  option  you  can  feed  ettercap with command as they were typed on the
              keyboard by the user. This way you can use ettercap within your favourite  scripts.
              There is a special command you can issue thru this command: s(x). this command will
              sleep for x seconds.

              example:

              ettercap -T -s 'lq'  will print the list of the hosts and exit
              ettercap -T -s 's(300)olqq'  will collect the infos for 5 minutes, print  the  list
              of the local profiles and exit

       -C, --curses
              Ncurses based GUI. See ettercap_curses(8) for a full description.

       -G, --gtk
              The nice GTK2 interface (thanks Daten...).

       -D, --daemonize
              Daemonize  ettercap.  This option will detach ettercap from the current controlling
              terminal and set it as a daemon. You can combine this feature with the "log" option
              to  log  all  the traffic in the background. If the daemon fails for any reason, it
              will create the file "./ettercap_daemonized.log"  in  which  the  error  caught  by
              ettercap will be reported. Furthermore, if you want to have a complete debug of the
              daemon process, you are encouraged to recompile ettercap in debug mode.

       GENERAL OPTIONS

       -b, --broadcast
              Tells Ettercap to process packets coming from Broadcast address.

       -i, --iface <IFACE>
              Use this <IFACE> instead of the default one.  The  interface  can  be  unconfigured
              (requires  libnet  >=  1.1.2), but in this case you cannot use MITM attacks and you
              should set the unoffensive flag.

       -I, --iflist
              This option will print the list of all available network  interfaces  that  can  be
              used  within  ettercap.  The  option is particularly useful under windows where the
              name of the interface is not so obvious as under *nix.

       -Y, --secondary <interface list>
              Specify a list of (or single) secondary interfaces to capture packets from.

       -A, --address <ADDRESS>
              Use this <ADDRESS> instead of the one autodetected  for  the  current  iface.  This
              option is useful if you have an interface with multiple ip addresses.

       -n, --netmask <NETMASK>
              Use  this  <NETMASK>  instead  of  the  one associated with the current iface. This
              option is useful if you have the NIC with an associated netmask of class B and  you
              want to scan (with the arp scan) only a class C.

       -R, --reversed
              Reverse  the  matching  in  the TARGET selection. It means not(TARGET). All but the
              selected TARGET.

       -t, --proto <PROTO>
              Sniff only PROTO packets (default is TCP + UDP).
              This is useful if you want to select a port via the TARGET  specification  but  you
              want to differentiate between tcp or udp.
              PROTO can be "tcp", "udp" or "all" for both.

       -6, --ip6scan
              Send ICMPv6 probes to discover active IPv6 nodes on the link.  This options sends a
              ping request to the all-nodes address to motivate active IPv6 hosts to respond. You
              should  not  use  this option if you try to hide yourself. Therefore this option is
              optional.

              NOTE: This option is only available if IPv6 support has been enabled.

       -z, --silent
              Do not perform the initial ARP scan of the LAN.

              NOTE: you will not have the hosts list, so you can't use the  multipoison  feature.
              you  can only select two hosts for an ARP poisoning attack, specifying them through
              the TARGETs

       -p, --nopromisc
              Usually, ettercap will put the interface in promisc mode to sniff all  the  traffic
              on  the  wire.  If  you  want  to sniff only your connections, use this flag to NOT
              enable the promisc mode.

       -S, --nosslmitm
              Usually, ettercap forges SSL certificates in  order  to  intercept  https  traffic.
              This option disables that behavior.

       -u, --unoffensive
              Every  time  ettercap starts, it disables ip forwarding in the kernel and begins to
              forward packets itself. This option prevent to do that, so the responsibility of ip
              forwarding is left to the kernel.
              This  options  is  useful  if you want to run multiple ettercap instances. You will
              have one instance (the one without the -u option) forwarding the packets,  and  all
              the  other  instances  doing their work without forwarding them. Otherwise you will
              get packet duplicates.
              It also disables the internal creation of the  sessions  for  each  connection.  It
              increases performances, but you will not be able to modify packets on the fly.
              If you want to use a mitm attack you have to use a separate instance.
              You  have  to  use  this  option  if  the  interface is unconfigured (without an ip
              address.)
              This is also useful if you want to run ettercap on the gateway. It will not disable
              the forwarding and the gateway will correctly route the packets.

       -j, --load-hosts <FILENAME>
              It  can  be  used  to  load a hosts list from a file created by the -k option. (see
              below)

       -k, --save-hosts <FILENAME>
              Saves the hosts list to a file. Useful when you have many hosts and you don't  want
              to  do  an  ARP storm at startup any time you use ettercap. Simply use this options
              and dump the list to a file, then to load  the  information  from  it  use  the  -j
              <filename> option.

       -P, --plugin <PLUGIN>
              Run  the  selected  PLUGIN.  Many  plugins need target specification, use TARGET as
              always. Use multiple occurrences of this parameter to select multiple plugins.
              In console  mode  (-C  option),  standalone  plugins  are  executed  and  then  the
              application exits. Hook plugins are activated and the normal sniffing is performed.
              To  have  a  list  of the available external plugins use "list" (without quotes) as
              plugin name (e.g. ./ettercap -P list).

              NOTE: you can also activate plugins directly from the interfaces (always press  "h"
              to get the inline help)

              More  detailed  info about plugins and about how to write your own are found in the
              man page ettercap_plugins(8)

       --plugin-list <PLUGIN1>[,<PLUGIN2>,...]
              Instead of providing multiple occurances of -P plugin, --plugin-list  can  be  used
              followed  by  a  comma  sepaparated  list  without  any  spaces.   (e.g. ./ettercap
              --plugin-list plugin1,plugin2).

       -F, --filter <FILE>
              Load  the  filter  from  the  file  <FILE>.  The  filter  must  be  compiled   with
              etterfilter(8).  The  utility  will  compile  the  filter  script  and  produce  an
              ettercap-compliant binary filter file. Read the etterfilter(8)  man  page  for  the
              list of functions you can use inside a filter script.  Any number of filters can be
              loaded by specifying the option multiple times; packets  are  passed  through  each
              filter  in  the  order  specified  on the command line.  You can also load a script
              without enabling it by appending :0 to the filename.
              NOTE: these filters are different from those set  with  --pcapfilter.  An  ettercap
              filter is a content filter and can modify the payload of a packet before forwarding
              it. Pcap filter are used to capture only certain packets.
              NOTE: you can use filters on pcapfile to modify them and save to another file,  but
              in  this  case you have to pay attention on what you are doing, since ettercap will
              not recalculate checksums, nor  split  packets  exceeding  the  mtu  (snaplen)  nor
              anything like that.

       -W, --wifi-key <KEY>
              You  can  specify  a  key  to  decrypt  WiFi packets (WEP or WPA). Only the packets
              decrypted successfully will be passed to the decoders stack,  the  others  will  be
              skipped with a message.
              The  parameter  has  the following syntax: type:bits:t:string. Where 'type' can be:
              wep, wpa-pws or wpa-psk, 'bits' is the bit length of the key (64, 128 or 256),  't'
              is  the type of the string ('s' for string and 'p' for passphrase). 'string' can be
              a string or an escaped hex sequences.

              example:
              --wifi-key wep:128:p:secret
              --wifi-key wep:128:s:ettercapwep0
              --wifi-key 'wep:64:s:\x01\x02\x03\x04\x05'
              --wifi-key wpa:pwd:ettercapwpa:ssid
              --wifi-key wpa:psk:
              663eb260e87cf389c6bd7331b28d82f5203b0cae4e315f9cbb7602f3236708a6

       -a, --config <CONFIG>
              Loads an alternative config file instead of the default in  /etc/etter.conf.   This
              is useful if you have many preconfigured files for different situations.

       --certificate <FILE>
              Tells Ettercap to use the specified certificate file for the SSL MiTM attack.

       --private-key <FILE>
              Tells Ettercap to use the specified private key file for the SSL MiTM attack.

       VISUALIZATION OPTIONS

       -e, --regex <REGEX>
              Handle only packets that match the regex.
              This  option  is useful in conjunction with -L. It logs only packets that match the
              posix regex REGEX.
              It impacts even the visualization of the sniffed packets. If it is set only packets
              matching the regex will be displayed.

       -V, --visual <FORMAT>
              Use this option to set the visualization method for the packets to be displayed.

              FORMAT may be one of the following:

              hex    Print the packets in hex format.

                     example:

                     the string  "HTTP/1.1 304 Not Modified"  becomes:

                     0000: 4854 5450 2f31 2e31 2033 3034 204e 6f74  HTTP/1.1 304 Not
                     0010: 204d 6f64 6966 6965 64                    Modified

              ascii  Print only "printable" characters, the others are displayed as dots '.'

              text   Print only the "printable" characters and skip the others.

              ebcdic Convert an EBCDIC text to ASCII.

              html   Strip  all  the html tags from the text. A tag is every string between < and
                     >.

                     example:

                     <title>This is the title</title>, but the following  <string>  will  not  be
                     displayed.

                     This is the title, but the following will not be displayed.

              utf8   Print  the  packets  in UTF-8 format. The encoding used while performing the
                     conversion is declared in the etter.conf(5) file.

       -d, --dns
              Resolve ip addresses into hostnames.

              NOTE: this may seriously slow down  ettercap  while  logging  passive  information.
              Every  time  a new host is found, a query to the dns is performed. Ettercap keeps a
              cache for already resolved host to increase the speed, but new  hosts  need  a  new
              query and the dns may take up to 2 or 3 seconds to respond for an unknown host.

              HINT:  ettercap collects the dns replies it sniffs in the resolution table, so even
              if you specify to not resolve the hostnames, some of them will be resolved  because
              the  reply  was  previously sniffed. think about it as a passive dns resolution for
              free... ;)

       -E, --ext-headers
              Print extended headers for every displayed packet. (e.g. mac addresses)

       -Q, --superquiet
              Super quiet mode. Do not print users and passwords  as  they  are  collected.  Only
              store  them in the profiles. It can be useful to run ettercap in text only mode but
              you don't want to be flooded with dissectors messages. Useful  when  using  plugins
              because  the  sniffing  process  is  always active, it will print all the collected
              infos, with this option you can suppress these messages.
              NOTE: this options automatically sets the -q option.

              example:

              ettercap -TzQP finger /192.168.0.1/22

       LOGGING OPTIONS

       -L, --log <LOGFILE>
              Log all the packets to binary files. These files can be parsed  by  etterlog(8)  to
              extract human readable data. With this option, all packets sniffed by ettercap will
              be logged, together with all the passive info (host info +  user  &  pass)  it  can
              collect.  Given  a  LOGFILE,  ettercap  will  create  LOGFILE.ecp (for packets) and
              LOGFILE.eci (for the infos).

              NOTE: if you specify this option on command line you don't have  to  take  care  of
              privileges since the log file is opened in the startup phase (with high privs). But
              if you enable the log option while ettercap is already started, you have to be in a
              directory where uid = 65535 or uid = EC_UID can write.

              NOTE:  the  logfiles  can  be  compressed  with  the deflate algorithm using the -c
              option.

       -l, --log-info <LOGFILE>
              Very similar to -L but it logs only passive information + users and  passwords  for
              each host. The file will be named LOGFILE.eci

       -m, --log-msg <LOGFILE>
              It  stores  in  <LOGFILE>  all  the  user messages printed by ettercap. This can be
              useful when you are using ettercap in daemon mode or if you want to track down  all
              the  messages.  Indeed, some dissectors print messages but their information is not
              stored anywhere, so this is the only way to keep track of them.

       -c, --compress
              Compress the logfile with the gzip algorithm while it  is  dumped.  etterlog(8)  is
              capable of handling both compressed and uncompressed log files.

       -o, --only-local
              Stores profiles information belonging only to the LAN hosts.

              NOTE:  this  option  is  effective  only  against the profiles collected in memory.
              While logging to a file ALL the hosts are logged. If you want to  split  them,  use
              the related etterlog(8) option.

       -O, --only-remote
              Stores profiles information belonging only to remote hosts.

       STANDARD OPTIONS

       -v, --version
              Print the version and exit.

       -h, --help
              prints the help screen with a short summary of the available options.

EXAMPLES

       Here are some examples of using ettercap.

       ettercap -Tp

              Use  the  console  interface and do not put the interface in promisc mode. You will
              see only your traffic.

       ettercap -Tzq

              Use the console interface, do not ARP scan the net and be quiet. The packet content
              will  not  be displayed, but user and passwords, as well as other messages, will be
              displayed.

       ettercap -T -j /tmp/victims -M arp /10.0.0.1-7/ /10.0.0.10-20/

              Will load the hosts list from /tmp/victims and  perform  an  ARP  poisoning  attack
              against  the  two target. The list will be joined with the target and the resulting
              list is used for ARP poisoning.

       ettercap -T -M arp // //

              Perform the ARP poisoning attack against all the hosts in the LAN. BE CAREFUL !!

       ettercap -T -M arp:remote /192.168.1.1/ /192.168.1.2-10/

              Perform the ARP poisoning against the gateway and the host in the lan between 2 and
              10.  The 'remote' option is needed to be able to sniff the remote traffic the hosts
              make through the gateway.

       ettercap -Tzq //110

              Sniff only the pop3 protocol from every hosts.

       ettercap -Tzq /10.0.0.1/21,22,23

              Sniff telnet, ftp and ssh connections to 10.0.0.1.

       ettercap -P list

              Prints the list of all available plugins

FILES

       ~/.config/ettercap_gtk

              Stores persistent information (e.g., window placement) between sessions.

ORIGINAL AUTHORS

       Alberto Ornaghi (ALoR) <alor@users.sf.net>
       Marco Valleri (NaGA) <naga@antifork.org>

PROJECT STEWARDS

       Emilio Escobar (exfil)  <eescobar@gmail.com>
       Eric Milam (Brav0Hax)  <jbrav.hax@gmail.com>

OFFICIAL DEVELOPERS

       Mike Ryan (justfalter)  <falter@gmail.com>
       Gianfranco Costamagna (LocutusOfBorg)  <costamagnagianfranco@yahoo.it>
       Antonio Collarino (sniper)  <anto.collarino@gmail.com>
       Ryan Linn   <sussuro@happypacket.net>
       Jacob Baines   <baines.jacob@gmail.com>

CONTRIBUTORS

       Dhiru Kholia (kholia)  <dhiru@openwall.com>
       Alexander Koeppe (koeppea)  <format_c@online.de>
       Martin Bos (PureHate)  <purehate@backtrack.com>
       Enrique Sanchez
       Gisle Vanem  <giva@bgnett.no>
       Johannes Bauer  <JohannesBauer@gmx.de>
       Daten (Bryan Schneiders)  <daten@dnetc.org>

SEE ALSO

       etter.conf(5)   ettercap_curses(8)    ettercap_plugins(8)    etterlog(8)    etterfilter(8)
       ettercap-pkexec(8)

AVAILABILITY

       https://github.com/Ettercap/ettercap/downloads

GIT

       git clone git://github.com/Ettercap/ettercap.git
       or
       git clone https://github.com/Ettercap/ettercap.git

BUGS

       Our software never has bugs.
       It just develops random features.   ;)

       KNOWN-BUGS

       -  ettercap  doesn't handle fragmented packets... only the first segment will be displayed
       by the sniffer. However all the fragments are correctly forwarded.

       +      please      send      bug-report,       patches       or       suggestions       to
       <ettercap-betatesting@lists.sourceforge.net>                    or                   visit
       https://github.com/Ettercap/ettercap/issues.

       + to report a bug, follow the instructions in the README.BUGS file

PHILOLOGICAL HISTORY

       "Even if blessed with a feeble intelligence, they are cruel and  smart..."   this  is  the
       description of Ettercap, a monster of the RPG Advanced Dungeons & Dragon.

       The  name  "ettercap"  was  chosen because it has an assonance with "ethercap" which means
       "ethernet capture" (what ettercap actually does) and also because  such  monsters  have  a
       powerful poison... and you know, arp poisoning... ;)

The Lord Of The (Token)Ring

       (the fellowship of the packet)

       "One Ring to link them all, One Ring to ping them,
        one Ring to bring them all and in the darkness sniff them."

Last words

       "Programming  today  is  a  race  between  software engineers striving to build bigger and
       better idiot-proof programs, and the Universe trying to produce bigger and better  idiots.
       So far, the Universe is winning." - Rich Cook