Provided by: strongswan-starter_4.4.0-2ubuntu1_i386 bug

NAME

       ipsec.conf - IPsec configuration and connections

DESCRIPTION

       The  optional  ipsec.conf file specifies most configuration and control
       information for the strongSwan IPsec subsystem.  (The  major  exception
       is secrets for authentication; see ipsec.secrets(5).)  Its contents are
       not security-sensitive.

       The file is a text file, consisting of one  or  more  sections.   White
       space  followed  by  # followed by anything to the end of the line is a
       comment and is ignored, as are empty  lines  which  are  not  within  a
       section.

       A  line  which  contains  include  and  a file name, separated by white
       space, is replaced by the contents of that file, preceded and  followed
       by  empty  lines.   If  the  file  name  is  not a full pathname, it is
       considered to be relative to the  directory  containing  the  including
       file.   Such  inclusions  can be nested.  Only a single filename may be
       supplied, and it may not contain white space, but it may include  shell
       wildcards (see sh(1)); for example:

       include ipsec.*.conf

       The  intention  of  the  include  facility  is mostly to permit keeping
       information on connections, or sets of connections, separate  from  the
       main  configuration file.  This permits such connection descriptions to
       be changed, copied to  the  other  security  gateways  involved,  etc.,
       without  having  to constantly extract them from the configuration file
       and then insert them back  into  it.   Note  also  the  also  parameter
       (described  below)  which  permits  splitting  a single logical section
       (e.g. a connection description) into several actual sections.

       A section begins with a line of the form:

       type name

       where type indicates what type of  section  follows,  and  name  is  an
       arbitrary  name which distinguishes the section from others of the same
       type.  (Names must start with a letter and may  contain  only  letters,
       digits,  periods,  underscores, and hyphens.)  All subsequent non-empty
       lines which begin with white space are part of  the  section;  comments
       within  a  section  must begin with white space too.  There may be only
       one section of a given type with a given name.

       Lines within the section are generally of the form

            parameter=value

       (note the mandatory preceding white space).  There can be  white  space
       on  either  side  of  the =.  Parameter names follow the same syntax as
       section names, and are specific to a section  type.   Unless  otherwise
       explicitly  specified, no parameter name may appear more than once in a
       section.

       An empty value stands for the system default  value  (if  any)  of  the
       parameter, i.e. it is roughly equivalent to omitting the parameter line
       entirely.  A value may contain white space only if the entire value  is
       enclosed  in  double quotes ("); a value cannot itself contain a double
       quote, nor may it be continued across more than one line.

       Numeric values are specified to be either an ‘‘integer’’ (a sequence of
       digits) or a ‘‘decimal number’’ (sequence of digits optionally followed
       by ‘.’ and another sequence of digits).

       There is currently one parameter which is  available  in  any  type  of
       section:

       also   the  value is a section name; the parameters of that section are
              appended to this section, as if they had been written as part of
              it.   The  specified section must exist, must follow the current
              one,  and  must  have  the  same  section  type.   (Nesting   is
              permitted,  and  there  may  be  more  than one also in a single
              section, although it is forbidden to  append  the  same  section
              more than once.)

       A  section  with  name  %default specifies defaults for sections of the
       same type.  For each parameter in it, any section of  that  type  which
       does  not have a parameter of the same name gets a copy of the one from
       the %default section.  There may be multiple  %default  sections  of  a
       given  type,  but  only  one  default  may be supplied for any specific
       parameter name, and all %default sections of a given type must  precede
       all  non-%default  sections  of  that  type.  %default sections may not
       contain the also parameter.

       Currently there are three types of sections: a config section specifies
       general  configuration  information for IPsec, a conn section specifies
       an IPsec connection, while a ca section specifies special properties of
       a certification authority.

CONN SECTIONS

       A  conn section contains a connection specification, defining a network
       connection to be made using IPsec.  The name given is arbitrary, and is
       used to identify the connection.  Here’s a simple example:

       conn snt
           left=192.168.0.1
           leftsubnet=10.1.0.0/16
           right=192.168.0.2
           rightsubnet=10.1.0.0/16
           keyingtries=%forever
           auto=add

       A  note on terminology: There are two kinds of communications going on:
       transmission of user IP packets,  and  gateway-to-gateway  negotiations
       for  keying,  rekeying,  and  general control.  The path to control the
       connection is called ’ISAKMP SA’ in  IKEv1  and  level  data  path,  is
       called  ’IPsec  SA’.   strongSwan  currently  uses  two separate keying
       daemons. Pluto handles all IKEv1 connections, Charon is the new  daemon
       supporting  the  IKEv2  protocol.  Charon does not support all keywords
       yet.

       To avoid trivial editing of the configuration file to suit it  to  each
       system  involved in a connection, connection specifications are written
       in terms of left and right participants, rather than in terms of  local
       and   remote.   Which  participant  is  considered  left  or  right  is
       arbitrary; IPsec figures out which one it is  being  run  on  based  on
       internal   information.    This   permits  using  identical  connection
       specifications on both  ends.   There  are  cases  where  there  is  no
       symmetry; a good convention is to use left for the local side and right
       for the remote side (the first letters are a good mnemonic).

       Many of the parameters relate to one participant or the other; only the
       ones  for  left  are listed here, but every parameter whose name begins
       with left has a right counterpart, whose description is  the  same  but
       with left and right reversed.

       Parameters are optional unless marked ’(required)’.

   CONN PARAMETERS
       Unless  otherwise  noted,  for  a  connection to work, in general it is
       necessary for the two ends to agree exactly  on  the  values  of  these
       parameters.

       ah            AH   authentication   algorithm   to   be  used  for  the
                     connection, e.g.  hmac-md5.

       auth          whether authentication should be  done  as  part  of  ESP
                     encryption,   or   separately   using  the  AH  protocol;
                     acceptable values are esp  (the  default)  and  ah.   The
                     IKEv2 daemon currently supports only ESP.

       authby        how  the  two  security gateways should authenticate each
                     other; acceptable values are secret or psk for pre-shared
                     secrets,  pubkey  (the default) for public key signatures
                     as well as the synonyms rsasig for RSA digital signatures
                     and  ecdsasig  for  Elliptic Curve DSA signatures.  never
                     can be used if negotiation is never to  be  attempted  or
                     accepted   (useful   for   shunt-only   conns).   Digital
                     signatures are superior in every way to  shared  secrets.
                     IKEv1  additionally  supports  the  values  xauthpsk  and
                     xauthrsasig  that  will  enable  eXtended  AUTHentication
                     (XAUTH)  in  addition  to IKEv1 main mode based on shared
                     secrets  or digital RSA signatures,  respectively.   This
                     parameter  is  deprecated  for  IKEv2 connections, as two
                     peers do not need to agree on an  authentication  method.
                     Use    the   leftauth   parameter   instead   to   define
                     authentication methods in IKEv2.

       auto          what operation, if any, should be done  automatically  at
                     IPsec  startup; currently-accepted values are add , route
                     , start and  ignore.   add  loads  a  connection  without
                     starting  it.   route  loads  a  connection  and installs
                     kernel traps. If traffic is detected  between  leftsubnet
                     and  rightsubnet  ,  a  connection is established.  start
                     loads a connection and brings it up  immediatly.   ignore
                     ignores  the  connection.  This  is  equal  to  delete  a
                     connection from the config file.  Relevant only  locally,
                     other  end  need  not agree on it (but in general, for an
                     intended-to-be-permanent connection, both ends should use
                     auto=start  to  ensure  that  any reboot causes immediate
                     renegotiation).

       compress      whether IPComp compression of content is proposed on  the
                     connection  (link-level  compression  does  not  work  on
                     encrypted data, so to be effective, compression  must  be
                     done before encryption); acceptable values are yes and no
                     (the default). A value of yes  causes  IPsec  to  propose
                     both  compressed and uncompressed, and prefer compressed.
                     A value of no prevents IPsec from proposing  compression;
                     a  proposal  to  compress  will still be accepted.  IKEv2
                     does not support IP compression yet.

       dpdaction     controls the use of  the  Dead  Peer  Detection  protocol
                     (DPD,  RFC  3706)  where  R_U_THERE notification messages
                     (IKEv1)  or  empty  INFORMATIONAL  messages  (IKEv2)  are
                     periodically sent in order to check the liveliness of the
                     IPsec peer. The  values  clear,  hold,  and  restart  all
                     activate DPD. If no activity is detected, all connections
                     with a dead peer are stopped and unrouted ( clear ),  put
                     in the hold state ( hold ) or restarted ( restart ).  For
                     IKEv1, the default is  none  which  disables  the  active
                     sending  of  R_U_THERE notifications.  Nevertheless pluto
                     will always send the DPD Vendor ID during connection  set
                     up in order to signal the readiness to act passively as a
                     responder if the peer wants to use DPD. For  IKEv2,  none
                     does’t  make sense, since all messages are used to detect
                     dead peers. If specified, it has the same meaning as  the
                     default ( clear ).

       dpddelay      defines  the  period  time  interval with which R_U_THERE
                     messages/INFORMATIONAL exchanges are sent  to  the  peer.
                     These  are  only sent if no other traffic is received. In
                     IKEv2, a value of 0  sends  no  additional  INFORMATIONAL
                     messages  and  uses only standard messages (such as those
                     to rekey) to detect dead peers.

       dpdtimeout    defines the timeout interval, after which all connections
                     to  a  peer  are deleted in case of inactivity. This only
                     applies to IKEv1, in  IKEv2  the  default  retransmission
                     timeout applies, as every exchange is used to detect dead
                     peers.

       inactivity    defines the timeout interval, after which a  CHILD_SA  is
                     closed  if  it  did  not  send  or  receive  any traffic.
                     Currently supported in IKEv2 connections only.

       eap           defines the EAP type to propose as server if  the  client
                     requests EAP authentication. This parameter is deprecated
                     in the favour of leftauth.

                     To forward EAP authentication to a  RADIUS  server  using
                     the EAP-RADIUS plugin, set eap=radius

       eap_identity  defines  the  identity  the client uses to reply to a EAP
                     Identity request.  If defined  on  the  EAP  server,  the
                     defined identity will be used as peer identity during EAP
                     authentication. The special value %identity uses the  EAP
                     Identity  method to ask the client for a EAP identity. If
                     not defined, the IKEv2  identity  will  be  used  as  EAP
                     identity.

       esp           ESP  encryption/authentication  algorithm  to be used for
                     the connection, e.g.  3des-md5 (encryption-integrity-[dh-
                     group]).  If  dh-group  is  specified, CHILD_SA setup and
                     rekeying include a separate diffe hellman exchange (IKEv2
                     only).

       forceencaps   Force  UDP  encapsulation  for ESP packets even if no NAT
                     situation  is  detected.   This  may   help   to   hurdle
                     restrictive firewalls. To enforce the peer to encapsulate
                     packets, NAT detection payloads are faked (IKEv2 only).

       ike           IKE/ISAKMP SA encryption/authentication algorithm  to  be
                     used,  e.g.   aes128-sha1-modp2048 (encryption-integrity-
                     dhgroup). In IKEv2, multiple algorithms and proposals may
                     be              included,             such             as
                     aes128-aes256-sha1-modp1536-modp2048,3des-
                     sha1-md5-modp1024.

       ikelifetime   how  long the keying channel of a connection (’ISAKMP/IKE
                     SA’) should last before being renegotiated.

       installpolicy decides whether  IPsec  policies  are  installed  in  the
                     kernel by the IKEv2 charon daemon for a given connection.
                     Allows peaceful co-existence e.g. with  the  Mobile  IPv6
                     daemon  mip6d  who  wants to control the kernel policies.
                     Acceptable values are yes (the default) and no.

       keyexchange   method of key exchange; which protocol should be used  to
                     initialize  the connection. Connections marked with ikev1
                     are initiated with pluto, those marked  with  ikev2  with
                     charon.  An  incoming  request  from  the  remote peer is
                     handled  by  the  correct  daemon,  unaffected  from  the
                     keyexchange  setting.  The  default  value  ike currently
                     behaves exactly as ikev1.

       keyingtries   how many attempts (a whole number or %forever) should  be
                     made to negotiate a connection, or a replacement for one,
                     before giving up (default %forever).  The value  %forever
                     means  ’never give up’.  Relevant only locally, other end
                     need not agree on it.

       keylife       synonym for lifetime.

       left          (required) the  IP  address  of  the  left  participant’s
                     public-network   interface,   in  any  form  accepted  by
                     ttoaddr(3) or one of several  magic  values.   If  it  is
                     %defaultroute,  left will be filled in automatically with
                     the local address  of  the  default-route  interface  (as
                     determined at IPsec startup time).  (Either left or right
                     may be %defaultroute, but  not  both.)   The  value  %any
                     signifies  an  address  to  be  filled  in  (by automatic
                     keying) during negotiation. The prefix % in  front  of  a
                     fully-qualified   domain  name  or  an  IP  address  will
                     implicitly set  leftallowany=yes.   If  the  domain  name
                     cannot be resolved into an IP address at IPsec startup or
                     update time then left=%any and  leftallowany=no  will  be
                     assumed.

       leftallowany  a modifier for left , making it behave as %any although a
                     concrete IP address has been assigned.   Recommended  for
                     dynamic  IP  addresses  that can be resolved by DynDNS at
                     IPsec startup or update time.  Acceptable values are  yes
                     and no (the default).

       leftauth      Authentication  method to use (local) or require (remote)
                     in this connection.  This parameter is supported in IKEv2
                     only.   Acceptable  values  are  pubkey  for  public  key
                     authentication  (RSA/ECDSA),  psk  for   pre-shared   key
                     authentication  and  eap  to  (require  the)  use  of the
                     Extensible Authentication Protocol. In the case  of  eap,
                     an optional EAP method can be appended. Currently defined
                     methods are eap-aka, eap-sim, eap-gtc, eap-md5  and  eap-
                     mschapv2.    Alternatively,   IANA  assigned  EAP  method
                     numbers are accepted. Vendor  specific  EAP  methods  are
                     defined in the form eap-type-vendor (e.g.  eap-7-12345 ).

       leftauth2     Same   as   leftauth,   but   defines    an    additional
                     authentication    exchange.   IKEv2   supports   multiple
                     authentication  rounds  using  "Multiple   Authentication
                     Exchanges"  defined in RFC4739. This allows, for example,
                     separated authentication of host and user (IKEv2 only).

       leftca        the distinguished name of a certificate  authority  which
                     is  required to lie in the trust path going from the left
                     participant’s certificate up to  the  root  certification
                     authority.

       leftca2       Same  as  leftca, but for the second authentication round
                     (IKEv2 only).

       leftcert      the path to the left participant’s X.509 certificate. The
                     file  can  be  coded either in PEM or DER format. OpenPGP
                     certificates are supported as well.  Both absolute  paths
                     or  paths relative to /etc/ipsec.d/certs are accepted. By
                     default leftcert sets leftid to the distinguished name of
                     the certificate’s subject and leftca to the distinguished
                     name of the certificate’s issuer.  The left participant’s
                     ID  can  be  overriden by specifying a leftid value which
                     must be certified by the certificate, though.

       leftcert2     Same as leftcert, but for the second authentication round
                     (IKEv2 only).

       leftfirewall  whether   the   left  participant  is  doing  forwarding-
                     firewalling (including masquerading) using  iptables  for
                     traffic  from leftsubnet, which should be turned off (for
                     traffic to the  other  subnet)  once  the  connection  is
                     established;  acceptable  values  are  yes  and  no  (the
                     default).   May  not  be  used  in  the  same  connection
                     description  with leftupdown.  Implemented as a parameter
                     to the default ipsec _updown script.   See  notes  below.
                     Relevant only locally, other end need not agree on it.

                     If  one  or  both  security gateways are doing forwarding
                     firewalling (possibly including masquerading),  and  this
                     is  specified  using  the  firewall  parameters,  tunnels
                     established with IPsec  are  exempted  from  it  so  that
                     packets  can  flow  unchanged through the tunnels.  (This
                     means that all subnets connected in this manner must have
                     distinct,  non-overlapping  subnet address blocks.)  This
                     is  done  by  the  default  ipsec  _updown  script   (see
                     pluto(8)).

                     In  situations  calling  for  more  control,  it  may  be
                     preferable for the user to supply his own updown  script,
                     which makes the appropriate adjustments for his system.

       leftgroups    a  comma separated list of group names. If the leftgroups
                     parameter is present then the peer must be a member of at
                     least  one  of the groups defined by the parameter. Group
                     membership  must  be  certified  by  a  valid   attribute
                     certificate  stored in /etc/ipsec.d/acerts/ thas has been
                     issued to the peer by a trusted  Authorization  Authority
                     stored  in  /etc/ipsec.d/aacerts/. Attribute certificates
                     are not supported in IKEv2 yet.

       lefthostaccess
                     inserts a pair of INPUT and OUTPUT iptables  rules  using
                     the default ipsec _updown script, thus allowing access to
                     the host itself in the case  where  the  host’s  internal
                     interface  is  part  of  the  negotiated  client  subnet.
                     Acceptable values are yes and no (the default).

       leftid        how  the  left  participant  should  be  identified   for
                     authentication;  defaults  to left.  Can be an IP address
                     (in any ttoaddr(3) syntax) or  a  fully-qualified  domain
                     name preceded by @ (which is used as a literal string and
                     not resolved).

       leftid2       identity to use for a second authentication for the  left
                     participant (IKEv2 only); defaults to leftid.

       leftikeport   UDP port the left participant uses for IKE communication.
                     Currently  supported  in  IKEv2  connections   only.   If
                     unspecified,  port 500 is used with port floating to 4500
                     if NAT is detected or MOBIKE enabled. Specifying a  local
                     IKE port different from the default additionally requires
                     a socket implementation that listens to this port.

       leftnexthop   this parameter is not needed any more because the  NETKEY
                     IPsec stack does not require explicit routing entries for
                     the traffic to be tunneled.

       leftprotoport restrict the traffic selector to a single protocol and/or
                     port.       Examples:      leftprotoport=tcp/http      or
                     leftprotoport=6/80 or leftprotoport=udp

       leftrsasigkey the left  participant’s  public  key  for  RSA  signature
                     authentication,  in  RFC  2537  format  using  ttodata(3)
                     encoding.  The magic value %none means the  same  as  not
                     specifying  a  value (useful to override a default).  The
                     value %cert (the default) means that the key is extracted
                     from  a  certificate.   The  identity  used  for the left
                     participant must be a specific host, not %any or  another
                     magic  value.   Caution:  if  two connection descriptions
                     specify  different  public  keys  for  the  same  leftid,
                     confusion and madness will ensue.

       leftsendcert  Accepted  values  are  never  or  no,  always or yes, and
                     ifasked.

       leftsourceip  The internal source IP to use in a tunnel, also known  as
                     virtual  IP.  If  the  value  is  %modeconfig,  %modecfg,
                     %config, or %cfg, an address is requested from the  peer.
                     In  IKEv2, a defined address is requested, but the server
                     may change it. If the server does  not  support  it,  the
                     address is enforced.

       rightsourceip The  internal source IP to use in a tunnel for the remote
                     peer. If the value is %config on the responder side,  the
                     initiator  must  propose  a  address which is then echoed
                     back.  The  IKEv2  daemon  also  supports  address  pools
                     expressed as network/netmask or the use of an external IP
                     address pool using %poolname , where poolname is the name
                     of the IP address pool used for the lookup.

       leftsubnet    private  subnet behind the left participant, expressed as
                     network/netmask  (actually,  any   form   acceptable   to
                     ttosubnet(3));  if  omitted,  essentially  assumed  to be
                     left/32, signifying that the left end of  the  connection
                     goes  to the left participant only. When using IKEv2, the
                     configured subnet of the peers may differ,  the  protocol
                     narrows  it to the greatest common subnet. Further, IKEv2
                     supports multiple subnets separated by commas. IKEv1 only
                     interprets the first subnet of such a definition.

       leftsubnetwithin
                     the peer can propose any subnet or single IP address that
                     fits within the range defined by  leftsubnetwithin.   Not
                     relevant for IKEv2, as subnets are narrowed.

       leftupdown    what  ‘‘updown’’  script  to run to adjust routing and/or
                     firewalling when the status  of  the  connection  changes
                     (default   ipsec   _updown).    May   include  positional
                     parameters  separated  by  white  space  (although   this
                     requires enclosing the whole string in quotes); including
                     shell  metacharacters  is  unwise.   See   pluto(8)   for
                     details.  Relevant only locally, other end need not agree
                     on it. IKEv2 uses the updown script  to  insert  firewall
                     rules   only.   Routing   is  not  support  and  will  be
                     implemented directly into Charon.

       lifebytes     the number of bytes transmitted over an IPsec  SA  before
                     it expires (IKEv2 only).

       lifepackets   the number of packets transmitted over an IPsec SA before
                     it expires (IKEv2 only).

       lifetime      how long a particular instance of a connection (a set  of
                     encryption/authentication  keys  for user packets) should
                     last, from successful negotiation to  expiry;  acceptable
                     values are an integer optionally followed by s (a time in
                     seconds) or a decimal number followed by m, h,  or  d  (a
                     time  in  minutes,  hours, or days respectively) (default
                     1h,  maximum   24h).    Normally,   the   connection   is
                     renegotiated  (via  the keying channel) before it expires
                     (see margintime).  The two ends need not exactly agree on
                     lifetime,  although  if  they  do not, there will be some
                     clutter of superseded connections on the end which thinks
                     the lifetime is longer.

       marginbytes   how  many  bytes  before  IPsec SA expiry (see lifebytes)
                     should attempts to negotiate a replacement  begin  (IKEv2
                     only).

       marginpackets how many packets before IPsec SA expiry (see lifepackets)
                     should attempts to negotiate a replacement  begin  (IKEv2
                     only).

       margintime    how  long  before  connection  expiry  or  keying-channel
                     expiry should attempts to negotiate a replacement  begin;
                     acceptable values as for lifetime (default 9m).  Relevant
                     only locally, other end need not agree on it.

       mobike        enables the IKEv2 MOBIKE protocol defined  by  RFC  4555.
                     Accepted  values are yes (the default) and no.  If set to
                     no, the IKEv2 charon daemon  will  not  actively  propose
                     MOBIKE  as  initiator  and  ignore  the  MOBIKE_SUPPORTED
                     notify as responder.

       modeconfig    defines which mode  is  used  to  assign  a  virtual  IP.
                     Accepted   values   are  push  and  pull  (the  default).
                     Currently relevant for IKEv1 only since IKEv2 always uses
                     the configuration payload in pull mode.

       pfs           whether Perfect Forward Secrecy of keys is desired on the
                     connection’s keying channel (with PFS, penetration of the
                     key-exchange protocol does not compromise keys negotiated
                     earlier); acceptable values are yes (the default) and no.
                     IKEv2  always  uses  PFS  for IKE_SA rekeying whereas for
                     CHILD_SA rekeying PFS is enforced by defining  a  Diffie-
                     Hellman modp group in the esp parameter.

       pfsgroup      defines   a  Diffie-Hellman  group  for  perfect  forward
                     secrecy in IKEv1 Quick Mode differing from the  DH  group
                     used for IKEv1 Main Mode (IKEv1 only).

       reauth        whether  rekeying of an IKE_SA should also reauthenticate
                     the peer. In IKEv1, reauthentication is always  done.  In
                     IKEv2,  a  value  of  no  rekeys without uninstalling the
                     IPsec SAs, a value of yes (the  default)  creates  a  new
                     IKE_SA  from scratch and tries to recreate all IPsec SAs.

       rekey         whether a connection should be renegotiated  when  it  is
                     about  to expire; acceptable values are yes (the default)
                     and no.  The two ends need not agree, but while  a  value
                     of    no    prevents    Pluto/Charon    from   requesting
                     renegotiation,  it  does  not   prevent   responding   to
                     renegotiation requested from the other end, so no will be
                     largely ineffective unless both ends agree on it.

       rekeyfuzz     maximum percentage by  which  marginbytes,  marginpackets
                     and  margintime should be randomly increased to randomize
                     rekeying  intervals  (important  for  hosts   with   many
                     connections); acceptable values are an integer, which may
                     exceed 100, followed by a ‘%’ (defaults  to  100%).   The
                     value of marginTYPE, after this random increase, must not
                     exceed lifeTYPE (where TYPE is one of bytes,  packets  or
                     time).    The   value  0%  will  suppress  randomization.
                     Relevant only locally, other end need not agree on it.

       rekeymargin   synonym for margintime.

       type          the type of the connection; currently the accepted values
                     are tunnel (the default) signifying a host-to-host, host-
                     to-subnet,   or   subnet-to-subnet   tunnel;   transport,
                     signifying  host-to-host transport mode; transport_proxy,
                     signifying the special Mobile IPv6 transport proxy  mode;
                     passthrough,  signifying  that no IPsec processing should
                     be done at all; drop, signifying that packets  should  be
                     discarded;  and reject, signifying that packets should be
                     discarded  and  a  diagnostic  ICMP   returned.    Charon
                     currently  supports  tunnel,  transport, and tunnel_proxy
                     connection types, only .

       xauth         specifies the role in the XAUTH protocol if activated  by
                     authby=xauthpsk  or  authby=xauthrsasig.  Accepted values
                     are server and client (the default).

   CONN PARAMETERS: IKEv2 MEDIATION EXTENSION
       The following parameters are  relevant  to  IKEv2  Mediation  Extension
       operation only.

       mediation     whether  this  connection  is a mediation connection, ie.
                     whether  this  connection  is  used  to   mediate   other
                     connections.   Mediation  connections create no child SA.
                     Acceptable values are no (the default) and yes.

       mediated_by   the name of the connection  to  mediate  this  connection
                     through.   If  given,  the  connection  will  be mediated
                     through the named mediation  connection.   The  mediation
                     connection must set mediation=yes.

       me_peerid     ID  as  which  the peer is known to the mediation server,
                     ie. which the other end of this connection  uses  as  its
                     leftid  on  its connection to the mediation server.  This
                     is the ID we request the mediation server to  mediate  us
                     with.   If  me_peerid  is  not given, the rightid of this
                     connection will be used as peer ID.

CA SECTIONS

       This  are  optional  sections  that  can  be  used  to  assign  special
       parameters  to a Certification Authority (CA). These parameters are not
       supported in IKEv2 yet.

       auto      currently can have either the value ignore or add

       cacert    defines a path to  the  CA  certificate  either  relative  to
                 /etc/ipsec.d/cacerts or as an absolute path.

       crluri    defines a CRL distribution point (ldap, http, or file URI)

       crluri1   synonym for crluri.

       crluri2   defines an alternative CRL distribution point (ldap, http, or
                 file URI)

       ldaphost  defines an ldap host. Currently used by IKEv1 only.

       ocspuri   defines an OCSP URI.

       ocspuri1  synonym for ocspuri.

       ocspuri2  defines an alternative OCSP  URI.  Currently  used  by  IKEv2
                 only.   certuribase defines the base URI for the Hash and URL
                 feature supported by IKEv2.  Instead of  exchanging  complete
                 certificates,  IKEv2  allows  to send an URI that resolves to
                 the DER encoded certificate. The certificate URIs  are  built
                 by appending the SHA1 hash of the DER encoded certificates to
                 this base URI.

CONFIG SECTIONS

       At present, the only config section known to the IPsec software is  the
       one  named  setup, which contains information used when the software is
       being started (see starter(8)).  Here’s an example:

       config setup
           plutodebug=all
           crlcheckinterval=10m
           strictcrlpolicy=yes

       Parameters are optional unless marked ‘‘(required)’’.   The  currently-
       accepted  parameter  names  in  a  config  setup section affecting both
       daemons are:

       cachecrls     certificate revocation lists (CRLs) fetched via  http  or
                     ldap  will be cached in /etc/ipsec.d/crls/ under a unique
                     file name  derived  from  the  certification  authority’s
                     public   key.   Accepted  values  are  yes  and  no  (the
                     default).

       charonstart   whether  to  start  the  IKEv2  Charon  daemon  or   not.
                     Accepted  values  are  yes  or no.  The default is yes if
                     starter was compiled with IKEv2 support.

       dumpdir       in what directory should things started by ipsec  starter
                     (notably the Pluto and Charon daemons) be allowed to dump
                     core?  The empty value (the default) means they  are  not
                     allowed  to.  This feature is currently not yet supported
                     by ipsec starter.

       plutostart    whether to start the IKEv1 Pluto daemon or not.  Accepted
                     values  are yes or no.  The default is yes if starter was
                     compiled with IKEv1 support.

       strictcrlpolicy
                     defines if a fresh CRL must be available in order for the
                     peer  authentication  based on RSA signatures to succeed.
                     Accepted values are yes  and  no  (the  default).   IKEv2
                     additionally  recognizes ifuri which reverts to yes if at
                     least one CRL URI is defined and  to  no  if  no  URI  is
                     known.

       uniqueids     whether  a  particular  participant  ID  should  be  kept
                     unique, with any  new  (automatically  keyed)  connection
                     using an ID from a different IP address deemed to replace
                     all old ones using that ID;  acceptable  values  are  yes
                     (the  default)  and  no.   Participant  IDs  normally are
                     unique, so a new (automatically-keyed)  connection  using
                     the  same  ID is almost invariably intended to replace an
                     old one.  The IKEv2 daemon also accepts the value replace
                     wich is identical to yes and the value keep to reject new
                     IKE_SA setups and keep the duplicate established earlier.

       The  following  config  section  parameters are used by the IKEv1 Pluto
       daemon only:

       crlcheckinterval
              interval in seconds. CRL fetching is enabled  if  the  value  is
              greater  than  zero.   Asynchronous, periodic checking for fresh
              CRLs is currently done by the IKEv1 Pluto daemon only.

       keep_alive
              interval in seconds between NAT keep alive packets, the  default
              being 20 seconds.

       nat_traversal
              activates   NAT  traversal  by  accepting  source  ISAKMP  ports
              different from udp/500 and being able of floating to udp/4500 if
              a  NAT  situation  is  detected.  Accepted values are yes and no
              (the default).  Used by IKEv1 only, NAT traversal  always  being
              active in IKEv2.

       nocrsend
              no  certificate  request payloads will be sent.  Accepted values
              are yes and no (the default).

       pkcs11initargs
              non-standard  argument   string   for   PKCS#11   C_Initialize()
              function; required by NSS softoken.

       pkcs11module
              defines the path to a dynamically loadable PKCS #11 library.

       pkcs11keepstate
              PKCS  #11  login sessions will be kept during the whole lifetime
              of the keying daemon. Useful with pin-pad  smart  card  readers.
              Accepted values are yes and no (the default).

       pkcs11proxy
              Pluto  will  act  as  a  PKCS #11 proxy accessible via the whack
              interface.  Accepted values are yes and no (the default).

       plutodebug
              how much Pluto debugging output  should  be  logged.   An  empty
              value,  or  the magic value none, means no debugging output (the
              default).  The magic value all  means  full  output.   Otherwise
              only the specified types of output (a quoted list, names without
              the --debug- prefix, separated by white space) are enabled;  for
              details on available debugging types, see pluto(8).

       plutostderrlog
              Pluto  will  not  use  syslog,  but  rather  log  to stderr, and
              redirect stderr to the argument file.

       postpluto
              shell command to run after starting Pluto  (e.g.,  to  remove  a
              decrypted  copy  of the ipsec.secrets file).  It’s run in a very
              simple way; complexities like I/O redirection  are  best  hidden
              within  a  script.   Any  output  is  redirected for logging, so
              running  interactive  commands  is  difficult  unless  they  use
              /dev/tty  or equivalent for their interaction.  Default is none.

       prepluto
              shell command to run before starting Pluto (e.g., to decrypt  an
              encrypted  copy  of the ipsec.secrets file).  It’s run in a very
              simple way; complexities like I/O redirection  are  best  hidden
              within  a  script.   Any  output  is  redirected for logging, so
              running  interactive  commands  is  difficult  unless  they  use
              /dev/tty  or equivalent for their interaction.  Default is none.

       virtual_private
              defines private networks using a wildcard notation.

       The following config section parameters are used by  the  IKEv2  Charon
       daemon only:

       charondebug
              how  much  Charon  debugging  output  should be logged.  A comma
              separated list containing type  level/pairs  may  be  specified,
              e.g: dmn 3, ike 1, net -1.  Acceptable values for types are dmn,
              mgr, ike, chd, job, cfg, knl, net, enc, lib and the level is one
              of  -1,  0, 1, 2, 3, 4 (for silent, audit, control, controlmore,
              raw, private).

       The following config section parameters only make sense  if  the  KLIPS
       IPsec  stack  is  used instead of the default NETKEY stack of the Linux
       2.6 kernel:

       fragicmp
              whether a tunnel’s need to fragment a packet should be  reported
              back  with  an  ICMP  message,  in an attempt to make the sender
              lower his PMTU estimate; acceptable values are yes (the default)
              and no.

       hidetos
              whether  a  tunnel  packet’s TOS field should be set to 0 rather
              than copied from the user packet inside; acceptable  values  are
              yes (the default) and no

       interfaces
              virtual  and  physical  interfaces  for  IPsec  to use: a single
              virtual=physical pair, a (quoted!) list of  pairs  separated  by
              white  space,  or  %none.   One  of  the pairs may be written as
              %defaultroute, which  means:  find  the  interface  d  that  the
              default  route  points  to,  and  then  act  as if the value was
              ‘‘ipsec0=d’’.  %defaultroute is the default; %none must be  used
              to denote no interfaces.

       overridemtu
              value  that the MTU of the ipsecn interface(s) should be set to,
              overriding IPsec’s (large) default.

CHOOSING A CONNECTION

       When choosing a connection to apply to an outbound packet caught with a
       %trap,  the  system  prefers the one with the most specific eroute that
       includes the packet’s source  and  destination  IP  addresses.   Source
       subnets  are examined before destination subnets.  For initiating, only
       routed connections are considered. For responding, unrouted  but  added
       connections are considered.

       When  choosing  a  connection  to use to respond to a negotiation which
       doesn’t match an ordinary conn,  an  opportunistic  connection  may  be
       instantiated.  Eventually,  its  instance  will  be /32 -> /32, but for
       earlier stages of the negotiation, there will not be enough information
       about the client subnets to complete the instantiation.

FILES

       /etc/ipsec.conf
       /etc/ipsec.d/aacerts
       /etc/ipsec.d/acerts
       /etc/ipsec.d/cacerts
       /etc/ipsec.d/certs
       /etc/ipsec.d/crls

SEE ALSO

       ipsec(8), pluto(8), starter(8), ttoaddr(3), ttodata(3)

HISTORY

       Written   for   the   FreeS/WAN project by Henry Spencer.  Extended for
       the strongSwan project <http://www.strongswan.org> by Andreas  Steffen.
       IKEv2-specific features by Martin Willi.

BUGS

       If  conns are to be added before DNS is available, left=FQDN will fail.

                                  27 Jun 2007                    IPSEC.CONF(5)