VPNC(8) 						  System Administration Utilities						   VPNC(8)

NAME

       vpnc - client for Cisco VPN3000 Concentrator, IOS and PIX

SYNOPSIS

       vpnc [--version] [--print-config] [--help] [--long-help] [options] [config files]

DESCRIPTION

       This manual page documents briefly the vpnc and vpnc-disconnect commands.

       vpnc  is  a VPN client for the Cisco 3000 VPN  Concentrator,  creating  a IPSec-like connection as a tunneling network device for the local
       system. It uses the TUN/TAP driver in  Linux  kernel  2.4  and  above  and device tun(4) on BSD. The created connection is presented  as  a
       tunneling network device to the local system.

       OBLIGATORY  WARNING:  the  most	used  configuration (XAUTH authentication with pre-shared keys and password authentication) is insecure by
       design, be aware of this fact when you use vpnc to exchange sensitive data like passwords!

       The vpnc daemon by itself does not set any routes, but it calls vpnc-script to do this job. vpnc-script displays a connect banner.  If  the
       concentrator  supplies  a network list for split-tunneling these networks are added to the routing table.  Otherwise the default-route will
       be modified to point to the tunnel.  Further a host route to the concentrator is added in the later case.  If the client host  needs  DHCP,
       care must be taken to add another host route to the DHCP-Server around the tunnel.

       The vpnc-disconnect command is used to terminate the connection previously created by vpnc and restore the previous routing configuration.

CONFIGURATION

       The daemon reads configuration data from the following places:
       o      command line options
       o      config file(s) specified on the command line
       o      /etc/vpnc/default.conf
       o      /etc/vpnc.conf
       o      prompting the user if not found above

       vpnc  can parse options and configuration files in any order. However the first place to set an option wins.  configuration filenames which
       do not contain a / will be searched at /etc/vpnc/<filename> and /etc/vpnc/<filename>.conf.  Otherwise <filename> and  <filename>.conf  will
       be used.  If no configuration file is specified on the command-line at all, both /etc/vpnc/default.conf and /etc/vpnc.conf will be loaded.

OPTIONS

       The program options can be either given as arguments (but not all of them for security reasons) or be stored in a configuration file.

       --gateway <ip/hostname>
	      IP/name of your IPSec gateway
       conf-variable: IPSec gateway <ip/hostname>

       --id <ASCII string>
	      your group name
       conf-variable: IPSec ID <ASCII string>

       (configfile only option)
	      your group password (cleartext)
       conf-variable: IPSec secret <ASCII string>

       (configfile only option)
	      your group password (obfuscated)
       conf-variable: IPSec obfuscated secret <hex string>

       --username <ASCII string>
	      your username
       conf-variable: Xauth username <ASCII string>

       (configfile only option)
	      PIN for Nortel Two-Factor Authentication
       conf-variable: Xauth PIN <ASCII string>

       (configfile only option)
	      your password (cleartext)
       conf-variable: Xauth password <ASCII string>

       (configfile only option)
	      your password (obfuscated)
       conf-variable: Xauth obfuscated password <hex string>

       --domain <ASCII string>
	      (NT-) Domain name for authentication
       conf-variable: Domain <ASCII string>

       --xauth-inter
	      enable interactive extended authentication (for challenge response auth)
       conf-variable: Xauth interactive

       --vendor <cisco/netscreen/nortel>
	      vendor of your IPSec gateway
	      Default: cisco
       conf-variable: Vendor <cisco/netscreen/nortel>

       --natt-mode <natt/none/force-natt/cisco-udp/nortel-udp>
	      Which NAT-Traversal Method to use:
	      o      natt -- NAT-T as defined in RFC3947
	      o      none -- disable use of any NAT-T method
	      o      force-natt  --  always use NAT-T encapsulation even without presence of a NAT device (useful if the OS captures all ESP traf-
		     fic)
	      o      cisco-udp -- Cisco proprietary UDP encapsulation, commonly over Port 10000
	      o      nortel-udp -- Nortel proprietary UDP encapsulation
	      Note: cisco-tcp encapsulation is not yet supported
	      Default: natt
       conf-variable: NAT Traversal Mode <natt/none/force-natt/cisco-udp/nortel-udp>

       --script <command>
	      command is executed using system() to configure the interface, routing and so on. Device name, IP, etc. are passed using	enviroment
	      variables,  see  README. This script is executed right after ISAKMP is done, but before tunneling is enabled. It is called when vpnc
	      terminates, too
	      Default: /etc/vpnc/vpnc-script
       conf-variable: Script <command>

       --dh <dh1/dh2/dh5>
	      name of the IKE DH Group
	      Default: dh2
       conf-variable: IKE DH Group <dh1/dh2/dh5>

       --pfs <nopfs/dh1/dh2/dh5/server>
	      Diffie-Hellman group to use for PFS
	      Default: server
       conf-variable: Perfect Forward Secrecy <nopfs/dh1/dh2/dh5/server>

       --enable-1des
	      enables weak single DES encryption
       conf-variable: Enable Single DES

       --enable-no-encryption
	      enables using no encryption for data traffic (key exchanged must be encrypted)
       conf-variable: Enable no encryption

       --nortel-client-id <list/0-65535/ASCII string>
	      Nortel Client version ID sent during connection.	Use "list" to print allowed values.
	      Default: V04_15
       conf-variable: Nortel Client ID <list/0-65535/ASCII string>

       --application-version <ASCII string>
	      Application Version to report. Note: Default string is generated at runtime.
	      Default: Cisco Systems VPN Client 0.5.3:Linux
       conf-variable: Application version <ASCII string>

       --ifname <ASCII string>
	      visible name of the TUN/TAP interface
       conf-variable: Interface name <ASCII string>

       --ifmode <tun/tap>
	      mode of TUN/TAP interface:
	      o      tun: virtual point to point interface (default)
	      o      tap: virtual ethernet interface
	      Default: tun
       conf-variable: Interface mode <tun/tap>

       --debug <0/1/2/3/99>
	      Show verbose debug messages
	      o
		      0: Do not print debug information.
	      o
		      1: Print minimal debug information.
	      o
		      2: Show statemachine and packet/payload type information.
	      o
		      3: Dump everything exluding authentication data.
	      o      99: Dump everything INCLUDING AUTHENTICATION data (e.g. PASSWORDS).
       conf-variable: Debug <0/1/2/3/99>

       --no-detach
	      Don't detach from the console after login
       conf-variable: No Detach

       --pid-file <filename>
	      store the pid of background process in <filename>
	      Default: /var/run/vpnc/pid
       conf-variable: Pidfile <filename>

       --local-addr <ip/hostname>
	      local IP to use for ISAKMP / ESP / ... (0.0.0.0 == automatically assign)
	      Default: 0.0.0.0
       conf-variable: Local Addr <ip/hostname>

       --local-port <0-65535>
	      local ISAKMP port number to use (0 == use random port)
	      Default: 500
       conf-variable: Local Port <0-65535>

       --udp-port <0-65535>
	      Local UDP port number to use (0 == use random port).  This is only relevant if cisco-udp nat-traversal is used.  This is the _local_
	      port, the remote udp port is discovered automatically.  It is especially not the cisco-tcp port.
	      Default: 10000
       conf-variable: Cisco UDP Encapsulation Port <0-65535>

       --dpd-idle <0,10-86400>
	      Send DPD packet after not receiving anything for <idle> seconds.	Use 0 to disable DPD completely (both ways).
	      Default: 300
       conf-variable: DPD idle timeout (our side) <0,10-86400>

       --non-inter
	      Don't ask anything, exit on missing options
       conf-variable: Noninteractive

       --auth-mode <default/cert/psk/hybrid/username/token/PIN-token/token-SW/gpassword>
	      Authentication mode:
	      o      default:	maps to vendor specific default mode
	      o      cert:	server + client certificate (not implemented yet)
	      o      psk:	Cisco pre-shared key (default for Cisco)
	      o      hybrid:	Cisco server certificate + xauth (if built with openssl support)
	      o      username:	Nortel User Name and Password Authentication
	      o      token:	Nortel Group Security - Response Only Token - Use Passcode (default for Nortel)
	      o      PIN-token: Nortel Group Security - Response Only Token - Use Two-Factor Card
	      o      token-SW:	Nortel Group Security - Response Only Token - Use SoftID Software (not implemented yet)
	      o      gpassword: Nortel Group Security - Group Password Authentication
	      Default: default
       conf-variable: IKE Authmode <default/cert/psk/hybrid/username/token/PIN-token/token-SW/gpassword>

       --ca-file <filename>
	      filename and path to the CA-PEM-File
       conf-variable: CA-File <filename>

       --ca-dir <directory>
	      path of the trusted CA-Directory
	      Default: /etc/ssl/certs
       conf-variable: CA-Dir <directory>

       --target-network <target network/netmask>
	      Target network in dotted decimal or CIDR notation
	      Default: 0.0.0.0/0.0.0.0
       conf-variable: IPSEC target network <target network/netmask>

       --print-config
	      Prints your configuration; output can be used as vpnc.conf

FILES

       /etc/vpnc.conf /etc/vpnc/default.conf
	      The default configuration file. You can specify the same config directives as with command line options and additionaly IPSec secret
	      and Xauth password both supplying a cleartext password. Scrambled passwords from the Cisco configuration profiles can be	used  with
	      IPSec obfuscated secret and Xauth obfuscated password.

	      See EXAMPLES for further details.

       /etc/vpnc/*.conf
	      vpnc  will  read	configuration files in this directory when the config filename (with or without .conf) is specified on the command
	      line.

EXAMPLES

       This is an example vpnc.conf with pre-shared keys:

	      IPSec gateway vpn.example.com
	      IPSec ID ExampleVpnPSK
	      IKE Authmode psk
	      IPSec secret PskS3cret!
	      Xauth username user@example.com
	      Xauth password USecr3t

       And another one with hybrid authentication (requires that vpnc was built with openssl support):

	      IPSec gateway vpn.example.com
	      IPSec ID ExampleVpnHybrid
	      IKE Authmode hybrid
	      CA-Dir /etc/vpnc
	      or
	      CA-File /etc/vpnc/vpn-example-com.pem
	      IPSec secret HybS3cret?
	      Xauth username user@example.com
	      Xauth password 123456

       The lines begin with a keyword (no leading spaces!).  The values start exactly one space after the keywords, and run to the  end  of  line.
       This  lets  you	put  any  kind of weird character (except CR, LF and NUL) in your strings, but it does mean you can't add comments after a
       string, or spaces before them.

       In case the the CA-Dir option is used, your certificate needs to be named something like 722d15bd.X, where X is a manually assigned  number
       to make sure that files with colliding hashes have different names. The number can be derived from the certificate file itself:

       openssl x509 -subject_hash -noout -in /etc/vpnc/vpn-example-com.pem

       See  also  the  --print-config  option  to  generate  a config file, and the example file in the package documentation directory where more
       advanced usage is demonstrated.

       Advanced features like manual setting of multiple target routes and disabling /etc/resolv.conf rewriting is documented in the README of the
       vpnc package.

TODO

       Certificate support (Pre-Shared-Key + XAUTH is known to be insecure).
       Further points can be found in the TODO file.

AUTHOR

       This  man-page  has  been written by Eduard Bloch <blade(at)debian.org> and Christian Lackas <delta(at)lackas.net>, based on vpnc README by
       Maurice Massar <vpnc(at)unix-ag.uni-kl.de>.  Permission is granted to copy, distribute and/or modify this document under the terms  of  the
       GNU General Public License, Version 2 any later version published by the Free Software Foundation.

       On Debian systems, the complete text of the GNU General Public License can be found in /usr/share/common-licenses/GPL.

SEE ALSO

       pcf2vpnc(1), cisco-decrypt(1), ip(8), ifconfig(8), route(1), http://www.unix-ag.uni-kl.de/~massar/vpnc/

vpnc version 0.5.3						     July 2010								   VPNC(8)