ipsec.conf: conn Reference » History » Version 71

Tobias Brunner, 30.06.2014 14:56
replay_window added

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{{title(ipsec.conf: conn Reference)}}
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h1. ipsec.conf: conn <name>
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h2. General Connection Parameters
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_aaa_identity = <id>_
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p((. defines the identity of the AAA backend used during IKEv2 EAP authentication. This is required if
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     the EAP client uses a method that verifies the server identity (such as EAP-TLS), but it does not
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     match the IKEv2 gateway identity.
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_ah = <cipher suites>_
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p((. comma-separated list of AH algorithms to be used for the connection, e.g. _sha1-sha256-modp1024_.
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     The notation is integrity[-dhgroup]. For IKEv2, multiple algorithms (separated by -) of the same type
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     can be included in a single proposal. IKEv1 only includes the first algorithm in a proposal.
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     Only either the *ah* or the *esp* keyword may be used, AH+ESP bundles are not supported.
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p((. There is no default, by default ESP is used. The daemon adds its extensive default proposal to the configured
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     value. To restrict it to the configured proposal an exclamation mark (!) can be added at the end.
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     *Note:* As a responder the daemon accepts the first supported proposal received from the peer. In order
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     to restrict a responder to only accept specific cipher suites, the strict flag (!, exclamation mark)
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     can be used, e.g: sha256-sha512-modp2048!
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p((. If dh-group is specified, CHILD_SA/Quick Mode setup and rekeying include a separate Diffe-Hellman exchange.
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p((. Refer to [[IKEv1CipherSuites]] and [[IKEv2CipherSuites]] for a list of valid keywords.
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p((. Available since [[5.1.1]].
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_aggressive = yes | *no*_
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p((. whether to use IKEv1 Aggressive or Main Mode (the default). Available since [[5.0.0]].
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_also = <section name>_
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p((. includes conn section <name>.
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_authby = *pubkey* | rsasig | ecdsasig | psk | secret | xauthrsasig | xauthpsk | never_
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p((. how the two security gateways should authenticate each other; acceptable values are *secret* or *psk*
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     for pre-shared secrets, *pubkey* (the default) for public key signatures as well as the synonyms *rsasig*
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     for RSA digital signatures and *ecdsasig* for Elliptic Curve DSA signatures.
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     *never*  can be used if negotiation is never to be attempted or accepted (useful for shunt-only conns).
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     Digital signatures are superior in every way to shared secrets. IKEv1 additionally supports the values
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     *xauthpsk* and *xauthrsasig* that will enable _eXtended Authentication (XAuth)_ in addition to IKEv1 main
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     mode based on shared secrets or digital RSA signatures,  respectively.
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     This parameter is deprecated for IKEv2 connections (and IKEv1 connections since [[5.0.0]]), as two peers
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     do not need to agree on an authentication method. Use the _left|rightauth_ parameter instead to define
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     authentication methods.
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_auto = *ignore* | add | route | start_
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p((. what operation, if any, should be done automatically at IPsec startup. *add* loads a connection without
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     starting it. *route* loads a connection and installs kernel traps. If traffic is detected between
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     _leftsubnet_ and _rightsubnet_, a connection is established. *start* loads a connection and brings
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     it up immediately. *ignore* ignores the connection. This is equal to deleting a connection from the config
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     file. Relevant only locally, other end need not agree on it.
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_closeaction = *none* | clear | hold | restart_
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p((. defines the action to take if the remote peer unexpectedly closes a CHILD_SA (IKEv2 only, see _dpdaction_ for
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     meaning of values). A _closeaction_ should not be used if the peer uses reauthentication or uniqueids checking,
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     as these events might trigger the defined action when not desired.
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_compress = yes | *no*_
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p((. whether IPComp compression of content is proposed on the connection (link-level compression does not work on
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     encrypted data, so to be effective, compression must be done before encryption). A value of *yes* causes the daemon
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     to propose both compressed and  uncompressed, and  prefer compressed. A value of *no* prevents the daemon from proposing or accepting compression.
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_dpdaction = *none* | clear | hold | restart_
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p((. controls the use of the Dead Peer Detection protocol (DPD, RFC 3706) where R_U_THERE notification messages
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     (IKEv1) or empty INFORMATIONAL messages (IKEv2) are periodically sent in order to check the liveliness of the
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     IPsec peer. The values *clear*, *hold*, and *restart* all activate DPD. If no activity is detected,
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     all  connections with a dead peer are stopped and unrouted (*clear*), put in the hold state (*hold*)
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     or restarted (*restart*). The default is *none* which disables the active sending of DPD messages.
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_dpddelay = *30s* | <time>_
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p((. defines  the  period time interval with which R_U_THERE messages/INFORMATIONAL exchanges are sent to the peer.
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     These are only sent if no other traffic is received. In IKEv2, a value of 0 sends no additional INFORMATIONAL
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     messages and uses only standard messages (such as those to rekey) to detect dead peers.
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_dpdtimeout = *150s* | <time>_
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p((. defines the timeout interval, after which all connections to a peer are deleted in case of inactivity.
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     This only applies to IKEv1, in IKEv2 the default [[Retransmission|retransmission timeout]] applies, as every exchange is used to
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     detect dead peers.
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_inactivity = <time>_
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p((. defines the timeout interval, after which a CHILD_SA is closed if it did not send or receive any traffic.
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     Not supported for IKEv1 connections prior to [[5.0.0]].
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_eap_identity = <id>_
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p((. defines the identity the client uses to reply to an EAP Identity request. If defined on the EAP server, the defined
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     identity  will be used as peer identity during EAP authentication. The special value _%identity_ uses the EAP Identity method
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     to ask the client for a EAP identity. If not defined, the IKEv2 identity will be used as EAP identity.
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_esp = <cipher suites>_
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p((. comma-separated list of ESP encryption/authentication algorithms to be used for the connection, e.g.
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     _aes128-sha256_. The notation is _encryption-integrity[-dhgroup][-esnmode]_.
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     For IKEv2, multiple algorithms (separated by -) of the same type can be included in a single proposal.
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     IKEv1 only includes the first algorithm in a proposal.  Only either the *ah* or the *esp* keyword may
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     be used, AH+ESP bundles are not supported.
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p((. Defaults to *aes128-sha1,3des-sha1*. The daemon adds its extensive default proposal to
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     this default or the configured value. To restrict it to the configured proposal an exclamation mark (*&#33;*)
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     can be added at the end.
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     *Note*: As a responder both daemons accept the first supported proposal received from the peer. In order
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     to restrict a responder to only accept specific cipher suites, the strict flag (*&#33;*, exclamation mark)
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     can be used, e.g: _aes256-sha512-modp4096!_
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p((. If _dh-group_ is specified, CHILD_SA setup and rekeying include a separate Diffe-Hellman exchange (since
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     [[5.0.0]] this also applies to IKEv1 Quick Mode).
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p((. Valid values for _esnmode_ (IKEv2 only) are _esn_ and _noesn_.  Specifying both negotiates extended sequence
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     number support with the peer, the default is *noesn*.
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p((. Refer to [[IKEv1CipherSuites]] and [[IKEv2CipherSuites]] for a list of valid keywords.
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_forceencaps = yes | *no*_
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p((.  force UDP encapsulation for ESP packets even if no NAT situation is detected.
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      This may help to surmount restrictive firewalls. In order to force the peer to
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      encapsulate packets, NAT detection payloads are faked.
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      Not supported for IKEv1 connections prior to [[5.0.0]].
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_fragmentation = yes | force | *no*_
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p((.  whether to use IKE fragmentation (proprietary IKEv1 extension). Fragmented messages sent by a peer are always
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      accepted irrespective of the value of this option. If set to *yes* and the peer supports it, larger IKE messages
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      will be sent in fragments (the maximum fragment size can be configured in [[strongswan.conf]]). If set to *force*
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      the initial IKE message will already be fragmented if required.
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      Available for IKEv1 connections since [[5.0.2]].
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_ike = <cipher suites>_
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p((. comma-separated list of IKE/ISAKMP SA encryption/authentication algorithms to be used, e.g.
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     _aes128-sha1-modp2048_. The notation is _encryption-integrity[-prf]-dhgroup_. In IKEv2, multiple algorithms
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     and proposals may be included, such as _aes128-aes256-sha1-modp1536-modp2048,3des-sha1-md5-modp1024_.
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p((. The ability to configure a PRF algorithm different to that defined for integrity protection was added with [[5.0.2]].
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     If no PRF is configured, the algorithms defined for integrity are proposed as PRF.  The prf keywords are the same as
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     the integrity algorithms, but have a _prf_ prefix (such as _prfsha1_, _prfsha256_ or _prfaesxcbc_).
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p((. Defaults to *aes128-sha1-modp2048,3des-sha1-modp1536* for IKEv1. The daemon adds its extensive default proposal
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     to this default or the configured value. To restrict it to the configured proposal an exclamation mark (*&#33;*) can be added at the end.
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     Refer to [[IKEv1CipherSuites]] and [[IKEv2CipherSuites]] for a list of valid keywords.
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p((. *Note*: As a responder both daemons accept the first supported proposal received from the peer. In order
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     to restrict a responder to only accept specific cipher suites, the strict flag (*&#33;*, exclamation mark)
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     can be used, e.g: _aes256-sha512-modp4096!_
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_ikedscp = *000000* | <DSCP field>_
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p((. Differentiated Services Field Codepoint to set on outgoing IKE packets sent
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     from this connection. The value is a six digit binary encoded string defining
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     the Codepoint to set, as defined in "RFC 2474":
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_ikelifetime = *3h* | <time>_
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p((. how long the keying channel of a connection (_ISAKMP or IKE SA_) should last before being renegotiated.
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     Also see [[ExpiryRekey|Expiry and Rekey]].
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_installpolicy = *yes* | no_
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p((. decides whether IPsec policies are installed in the kernel by the charon daemon for a given connection.
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     Allows peaceful cooperation e.g. with the Mobile IPv6  _mip6d_ daemon who wants to control the kernel policies.
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_keyexchange = *ike* | ikev1 | ikev2_
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p((. method of key exchange; which protocol should be used to initialize the connection.
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     Prior to [[5.0.0]] connections marked with *ikev1*  were initiated with Pluto, those marked with *ikev2* with Charon.
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     An incoming request from the remote peer was handled by the correct daemon, unaffected from the _keyexchange_ setting.
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     Starting with strongSwan [[4.5.0]] the default value *ike* is a synonym for *ikev2*, whereas in older strongSwan releases *ikev1* was assumed.
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     Since [[5.0.0]] both protocols are handled by Charon and connections marked with *ike* will use IKEv2 when initiating, but accept any protocol version when responding.
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_keyingtries = *3* | <number> | %forever_
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p((. how  many attempts (a positive integer or _%forever_) should be made to negotiate a connection, or a replacement
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     for one, before giving up (default 3). The value _%forever_ means 'never give up'.  Relevant  only  locally, other end need
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     not agree on it.
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p((. synonym for _lifetime_.
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_lifebytes = <number>_
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p((. the number of bytes transmitted over an IPsec SA before it expires. Not supported for IKEv1 connections prior to [[5.0.0]].
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_lifepackets = <number>_
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p((. the number of packets transmitted over an IPsec SA before it expires. Not supported for IKEv1 connections prior to [[5.0.0]].
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_lifetime = *1h* | <time>_
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p((. how  long  a  particular  instance  of a connection (a set of encryption/authentication keys for user packets)
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     should last, from successful negotiation to expiry; acceptable values are an integer optionally followed by
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     _s_ (a time in seconds) or a decimal number followed by _m_, _h_, or _d_ (a time in minutes, hours,
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     or days respectively) (default _1h_, maximum _24h_).  Normally, the connection is renegotiated (via the
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     keying  channel) before it expires (see _margintime_).  The two ends need not exactly agree on _lifetime_, although if they
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     do not, there will be some clutter of superseded connections on the end which thinks the lifetime is longer.
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     Also see [[ExpiryRekey|Expiry and Rekey]].
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_marginbytes = <number>_
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p((. how many bytes before IPsec SA expiry (see _lifebytes_) should attempts to negotiate a replacement begin.
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_marginpackets = <number>_
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p((. how many packets before IPsec SA expiry (see _lifepackets_) should attempts to negotiate a replacement begin.
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_margintime = *9m* | <time>_
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p((. how long before connection expiry or keying-channel expiry should attempts to negotiate a replacement begin; acceptable values
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     as for _lifetime_ (default _9m_).  Relevant only locally, other end need not agree on it. Also see [[ExpiryRekey|Expiry and Rekey]].
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_mark = <value>[/<mask>]_
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p((. sets  an XFRM mark in the inbound and outbound IPsec SAs and policies. If the mask is missing then
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     a default mask of *0xffffffff* is assumed.
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_mark_in = <value>[/<mask>]_
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p((. sets an XFRM mark in the inbound IPsec SA and policy. If the mask is missing then
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     a default mask of *0xffffffff* is assumed.
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_mark_out = <value>[/<mask>]_
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p((. sets an XFRM mark in the outbound IPsec SA and policy. If the mask is missing then
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     a default mask of *0xffffffff* is assumed.
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_mobike = *yes* | no_
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p((. enables the IKEv2 [[MobIke|MOBIKE]] protocol defined by RFC 4555. If set to *no*, the charon
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     daemon will not actively propose [[MobIke|MOBIKE]] as initiator and ignore the MOBIKE_SUPPORTED
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     notify as responder.
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_modeconfig = push | *pull*_
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p((. defines which mode is used to assign a virtual IP. Currently relevant for IKEv1 only since IKEv2 always uses
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     the configuration payload in *pull* mode. Cisco VPN gateways usually operate in *push* mode.
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     In versions prior to [[5.1.1]] the charon daemon did not support *push* mode.
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_reauth = *yes* | no_
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p((. whether rekeying of an IKE_SA should also reauthenticate the peer. In IKEv1, reauthentication is always done.
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     In  IKEv2, a value of *no* rekeys without uninstalling the IPsec SAs, a value of *yes* (the default)
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     creates a new IKE_SA from scratch and tries to recreate all IPsec SAs.
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_rekey = *yes* | no_
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p((. whether a connection should be renegotiated when it is about to expire. The two ends need not agree, but
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     while a value of no prevents the daemon from requesting renegotiation, it does not prevent responding
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     to renegotiation requested from the other end, so no will be largely ineffective unless both ends agree on it.
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     Also see _reauth_.
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_rekeyfuzz = *100%* | <percentage>_
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p((. maximum percentage by which _marginbytes_, _marginpackets_ and _margintime_ should be randomly increased to randomize
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     rekeying intervals (important for hosts with many connections); acceptable values are an integer, which may exceed 100,
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     followed  by  a '%' .
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     The value of _marginTYPE_, after this random increase, must not exceed _lifeTYPE_ (where TYPE is one of bytes, packets or type).
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     The value _0%_ will suppress randomization. Relevant only locally, other end need not agree on it.
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     Also see [[ExpiryRekey|Expiry and Rekey]].
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p((.  synonym for _margintime_.
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_replay_window = -1 | <number>_
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p((. The  IPsec  replay  window  size  for  this connection. With the default of -1 the value configured with _charon.replay_window_  in
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     [[strongswan.conf]]  is used. Larger values than 32 are supported using the Netlink backend only, a  value  of  0  disables  IPsec
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     replay protection. Available since [[5.2.0]].
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_reqid = <number>_
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p((. sets the reqid for a given connection to a pre-configured fixed value.
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_tfc = <value>_
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p((. number of bytes to pad ESP payload data to. Traffic Flow Confidentiality is currently supported in IKEv2 and applies to outgoing packets only. The special value %mtu fills up ESP packets with padding to have the size of the MTU.
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_type = *tunnel* | transport | transport_proxy | passthrough | drop_
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p((. the type of the connection; currently the accepted values are *tunnel*, signifying a  host-to-host,
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     host-to-subnet, or subnet-to-subnet tunnel; *transport*, signifying host-to-host transport mode;
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     *transport_proxy*, signifying the special Mobile IPv6 transport proxy mode;
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     *passthrough*, signifying that no IPsec processing should be done at all; *drop*, signifying that packets
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     should be  discarded.
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_xauth = *client* | server_
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p((. specifies the role in the XAuth protocol if activated by _authby=xauthpsk_ or _authby=xauthrsasig_.
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_xauth_identity = <id>_
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p((. defines the identity/username the client uses to reply to an XAuth request. If not defined, the IKEv1 identity will be used as XAuth identity.
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h2. left|right End Parameters
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Connection descriptions are defined in terms of a left endpoint and a right endpoint. For example, the
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two parameters leftid and rightid specify the identity of the left and the right endpoint. For every
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connection description an attempt is made to figure out whether the local endpoint should act as the left or
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the right endpoint. This is done by matching the IP addresses defined for both endpoints with the
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IP addresses assigned to local network interfaces. If a match is found then the role (left or right) that
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matches is going to be considered "local". If no match is found during startup, "left" is considered "local".
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_left|right = <ip address> | <fqdn> | *%any* | range | subnet_
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p((. The IP address of the participant's public-network interface or one of several magic values.
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     The value _%any_ for the local endpoint signifies an address to be filled in
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     (by automatic keying) during negotiation. If the local peer initiates the connection setup the routing table
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     will be queried to determine the correct local IP address. In case the local peer is responding to a connection
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     setup then any IP address that is assigned to a local interface will be accepted.
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p((. Prior to [[5.0.0]] specifying _%%any_ for the local endpoint was not supported for IKEv1 connections, instead
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     the keyword _%%defaultroute_ could be used, causing the value to be filled in automatically with the local
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     address of the default-route interface (as determined at IPsec startup time and during configuration
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     update). Either left or right may be _%defaultroute_, but not both.
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p((. The prefix % in front of a fully-qualified domain name or an IP address will implicitly set _left|rightallowany=yes_.
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p((. If _%any_ is used for the remote endpoint it literally means any IP address.
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p((. Since [[5.1.1]] connections can be limited to a specific range of hosts. To do so a range (
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     or a subnet ( can be specified, and multiple addresses, ranges and subnets can be separated by commas.
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     While one can freely combine these items, to initiate the connection at least one non-range/subnet is required.
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p((. Please note that with the usage of wildcards multiple connection descriptions might match a given incoming
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     connection attempt. The most specific description is used in that case.
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_left|rightallowany = yes | *no*_
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p((. a modifier for _left|right_, making it behave as _%any_ although a concrete IP address has been
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     assigned. Recommended for dynamic IP addresses that can be resolved by DynDNS at IPsec startup or update time.
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_left|rightauth = <auth method>_
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p((. Authentication method to use locally (left) or require from the remote (right) side. Acceptable values are *pubkey*
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     for public key encryption (RSA/ECDSA), *psk* for pre-shared key authentication, *eap* to [require the] use of the Extensible Authentication Protocol, and *xauth* for IKEv1 eXtended Authentication.
352 32 Daniel Mentz
     To require a trustchain public key strength for the remote side, specify the key type followed
353 57 Tobias Brunner
     by the minimum strength iin bits (for example *ecdsa-384* or *rsa-2048-ecdsa-256*).
354 57 Tobias Brunner
     To limit the acceptable set of hashing algorithms for trustchain validation, append hash algorithms
355 57 Tobias Brunner
     to *pubkey* or a key strength definition (for example *pubkey-sha1-sha256* or *rsa-2048-ecdsa-256-sha256-sha384-sha512*).
356 1 Martin Willi
     In the case of *eap*, an optional EAP method can be appended. Currently defined methods are *eap-aka*,
357 58 Tobias Brunner
     *eap-gtc*, *eap-md5*, *eap-mschapv2*, *eap-peap*, *eap-sim*, *eap-tls*, *eap-ttls*, *eap-dynamic*, and *eap-radius*.
358 58 Tobias Brunner
     Alternatively, IANA assigned EAP method numbers are accepted. Vendor specific EAP methods are defined in the form
359 1 Martin Willi
     *eap-type-vendor* (e.g. *eap-7-12345*).
360 1 Martin Willi
     For *xauth*, an XAuth authentication backend can be specified, such as *xauth-generic* or *xauth-eap*. If XAuth is used in _leftauth_, Hybrid authentication is used. For traditional XAuth authentication, define XAuth in _leftauth2_.
361 1 Martin Willi
362 66 Andreas Steffen
p((. Not supported for IKEv1 connections prior to [[5.0.0]].
363 1 Martin Willi
364 57 Tobias Brunner
365 27 Daniel Mentz
_left|rightauth2 = <auth method>_
366 33 Tobias Brunner
367 58 Tobias Brunner
p((. Same as _left|rightauth_, but defines an additional authentication exchange. In IKEv1, only XAuth can be used
368 58 Tobias Brunner
     in the second authentication round. IKEv2 supports multiple complete authentication rounds using
369 58 Tobias Brunner
     _Multiple Authentication Exchanges_ defined in "RFC 4739": This allows e.g. a separate authentication of host and user.
370 57 Tobias Brunner
371 66 Andreas Steffen
p((. Not supported for IKEv1 connections prior to [[5.0.0]].
372 7 Martin Willi
373 31 Martin Willi
374 57 Tobias Brunner
_left|rightca = <issuer dn> | %same_
375 23 Tobias Brunner
376 57 Tobias Brunner
p((. the distinguished name of a certificate authority which is required to lie in the trust path going from the
377 57 Tobias Brunner
     _left|right_ participant's certificate up to the root certification authority.
378 58 Tobias Brunner
     *%same* means that the value configured for the other participant should be reused.
379 56 Andreas Steffen
380 1 Martin Willi
_left|rightca2 = <issuer dn> | %same_
381 56 Andreas Steffen
382 23 Tobias Brunner
p((. Same as _left|rightca_ but for the second authentication (IKev2 only).
383 21 Andreas Steffen
384 1 Martin Willi
_left|rightcert = <path>_
385 1 Martin Willi
386 1 Martin Willi
p((. the path to the left|right participant's X.509 certificate. The file can be coded either in PEM or DER format.
387 1 Martin Willi
     OpenPGP certificates are supported as well.  Both absolute paths or paths relative to
388 23 Tobias Brunner
     [[IpsecDirectoryCerts|/etc/ipsec.d/certs]] are accepted. By default _left|rightcert_ sets _left|rightid_
389 58 Tobias Brunner
     to the distinguished name of the certificate's subject. The _left|right_ participant's ID can be overridden
390 58 Tobias Brunner
     by specifying a _left|rightid_ value which must be certified by the certificate, though.
391 31 Martin Willi
392 61 Tobias Brunner
p((. Since [[5.0.2]] certificates can be configured in the form _%smartcard[<slot nr>[@<module>]]:<keyid>_, which
393 61 Tobias Brunner
     defines a specific certificate to load from a PKCS#11 backend for this connection (e.g. via the [[PKCS11Plugin|pkcs11 plugin]]).
394 61 Tobias Brunner
     See [[PinSecret|ipsec.secrets]] for details about smartcard definitions.
395 61 Tobias Brunner
     Defining a certificate on a smartcard with _left|rightcert_ is only required if the automatic selection via _left|rightid_
396 61 Tobias Brunner
     is not sufficient, for example, if multiple certificates use the same subject.
397 61 Tobias Brunner
398 64 Tobias Brunner
p((. Since [[5.0.3]] multiple certificate paths or PKCS#11 backends can be specified in a comma separated list.
399 64 Tobias Brunner
     The daemon chooses the certificate based on the received certificate requests, if possible, before enforcing
400 64 Tobias Brunner
     the first.
401 64 Tobias Brunner
402 23 Tobias Brunner
_left|rightcert2 = <path>_
403 23 Tobias Brunner
404 57 Tobias Brunner
p((. Same as _left|rightcert_ but for the second authentication round (IKEv2 only).
405 21 Andreas Steffen
406 1 Martin Willi
_left|rightcertpolicy = <OIDs>_
407 33 Tobias Brunner
408 7 Martin Willi
p((. Comma separated list of certificate policy OIDs the peer's certificate must have.
409 66 Andreas Steffen
     OIDs are specified using the numerical dotted representation. Not supported for IKEv1 connections prior to [[5.0.0]].
410 1 Martin Willi
411 58 Tobias Brunner
_left|rightdns = <servers>_
412 58 Tobias Brunner
413 58 Tobias Brunner
p((. Comma separated list of DNS server addresses to exchange as configuration attributes. On the initiator,
414 58 Tobias Brunner
     a server is a fixed IPv4/IPv6 address, or _%config4/%config6_ to request attributes without an address.
415 58 Tobias Brunner
     On the responder, only fixed IPv4/IPv6 addresses are allowed and define DNS servers assigned to the client.
416 58 Tobias Brunner
     Available since [[5.0.1]].
417 58 Tobias Brunner
418 1 Martin Willi
_left|rightfirewall = yes | *no*_
419 23 Tobias Brunner
420 1 Martin Willi
p((. whether the _left|right_ participant is doing forwarding-firewalling (including  masquerading)
421 1 Martin Willi
     using iptables for traffic from _left|rightsubnet_, which should be turned off for traffic to the
422 1 Martin Willi
     other subnet) once the connection is established. May not be used in the same connection description with
423 1 Martin Willi
     _left|rightupdown_. Implemented as a parameter to the default _ipsec _updown_ script. Relevant only
424 1 Martin Willi
     locally, other end need not agree on it.
425 1 Martin Willi
426 1 Martin Willi
p((. If one or  both security gateways are doing forwarding firewalling (possibly including masquerading),
427 23 Tobias Brunner
     and this is specified using the firewall parameters, tunnels  established with  IPsec  are exempted from
428 20 Andreas Steffen
     it so that packets can flow unchanged through the tunnels. (This means that all subnets connected in this
429 23 Tobias Brunner
     manner must have distinct, non-overlapping subnet address blocks.)  This is done by the default 
430 57 Tobias Brunner
     _ipsec _updown_ script.
431 1 Martin Willi
432 1 Martin Willi
p((. In situations calling for more control, it may be preferable for the user to supply his own _updown_ script,
433 1 Martin Willi
     which makes the appropriate adjustments for his system.
434 1 Martin Willi
435 1 Martin Willi
_left|rightgroups = <group list>_
436 1 Martin Willi
437 31 Martin Willi
p((. a comma-separated list of group names. If the _left|rightgroups_ parameter is present then the peer must
438 58 Tobias Brunner
     be a member of at least one of the groups defined by the parameter. Groups may be used together with the
439 58 Tobias Brunner
     [[EapRadius#Group-selection|eap-radius]] plugin.
440 57 Tobias Brunner
441 58 Tobias Brunner
_left|rightgroups2 = <group list>_
442 1 Martin Willi
443 58 Tobias Brunner
p((. Same as _left|rightgroups_ but for the second authentication round defined with _left|rightauth2_.
444 58 Tobias Brunner
     Available since [[5.0.1]].
445 58 Tobias Brunner
446 1 Martin Willi
_left|righthostaccess = yes | *no*_
447 1 Martin Willi
448 1 Martin Willi
p((. inserts a pair of INPUT and OUTPUT iptables rules using the default _ipsec _updown_ script,
449 1 Martin Willi
     thus allowing access to the host itself in the case where the host's internal interface is part
450 1 Martin Willi
     of the negotiated client subnet. 
451 33 Tobias Brunner
452 23 Tobias Brunner
_left|rightid = <id>_
453 57 Tobias Brunner
454 57 Tobias Brunner
p((. how the _left|right_ participant should be identified for authentication; defaults to _left|right_ or the subject of the certificate configured with _left|rightcert_.
455 57 Tobias Brunner
     Can be an IP address, a fully-qualified domain name, an email address, or a keyid.
456 33 Tobias Brunner
     Prior to [[5.0.0]] fully-qualified domain names can be preceded by an @ to avoid them being resolved to an IP address.
457 23 Tobias Brunner
458 58 Tobias Brunner
p((. Since [[5.0.1]] _rightid_ for IKEv2 connections optionally takes a % as prefix in front of the identity.
459 58 Tobias Brunner
     If given it prevents the daemon from sending IDr in its IKE_AUTH request and will allow it to verify the 
460 58 Tobias Brunner
     configured identity against the subject and subjectAltNames contained in the responder's certificate (otherwise,
461 58 Tobias Brunner
     it is only compared with the IDr returned by the responder). The IDr sent by the initiator might otherwise 
462 58 Tobias Brunner
     prevent the responder from finding a config if it has configured a different value for _leftid_.
463 58 Tobias Brunner
464 33 Tobias Brunner
_left|rightid2 = <id>_
465 7 Martin Willi
466 23 Tobias Brunner
p((. Identity to use for the second authentication of the left participant (IKEv2 only).
467 23 Tobias Brunner
     Defaults to _left|rightid_.
468 21 Andreas Steffen
469 1 Martin Willi
_leftikeport = <port>_
470 1 Martin Willi
471 1 Martin Willi
p((. UDP port the left participant uses for IKE communication. If unspecified, port 500 is used with the port
472 1 Martin Willi
     floating to 4500 if a NAT is detected or MOBIKE is enabled.
473 58 Tobias Brunner
     Specifying a local IKE port different from the default additionally requires a socket implementation that
474 58 Tobias Brunner
     listens to this port. Not supported for IKEv1 connections prior to [[5.0.0]].
475 63 Tobias Brunner
476 63 Tobias Brunner
_left|rightprotoport = <protocol>/<port>_
477 63 Tobias Brunner
478 70 Tobias Brunner
p((. restrict the traffic selector to a single protocol and/or port.  Since [[5.1.0]] this option is deprecated
479 70 Tobias Brunner
     as protocol/port information can be defined for each subnet directly in _left|rightsubnet_.
480 67 Tobias Brunner
481 1 Martin Willi
_left|rightrsasigkey = <raw rsa public key> | <path to public key>_
482 1 Martin Willi
483 67 Tobias Brunner
p((. Since [[5.1.0]] a synonym for _left|rightsigkey_. Before that it denoted the left|right participant's public key
484 67 Tobias Brunner
for RSA signature authentication, in RFC 2537 format using hex (0x prefix) or base64 (0s prefix) encoding.
485 67 Tobias Brunner
Also accepted is the path to a file containing the public key in PEM or DER encoding.
486 1 Martin Willi
487 67 Tobias Brunner
_left|rightsigkey = <raw public key> | <path to public key>_
488 67 Tobias Brunner
489 67 Tobias Brunner
p((. Added with [[5.1.0]]. The left|right participant's public key for public key signature authenticaiton, in PKCS#1
490 67 Tobias Brunner
format using  using hex (0x prefix) or base64 (0s prefix) encoding. With the optional _dns:_ or _ssh:_ prefix in front
491 67 Tobias Brunner
of 0x or 0x, the public key is expected in either the RFC 3110 (not the full RR, only the RSA key part) or
492 67 Tobias Brunner
RFC 4253 public key format, respectively.
493 67 Tobias Brunner
Also accepted is the path to a file containing the public key in PEM or DER encoding.
494 67 Tobias Brunner
495 1 Martin Willi
_left|rightsendcert = never | no | *ifasked* | always | yes_
496 1 Martin Willi
497 1 Martin Willi
p((. Accepted values are *never* or *no*, *always* or *yes*, and *ifasked*, the latter meaning that 
498 1 Martin Willi
     the peer must send a certificate request (CR) payload in order to get a certificate in return.
499 1 Martin Willi
500 58 Tobias Brunner
_leftsourceip = %config4 | %config6 | <ip address>_
501 1 Martin Willi
502 1 Martin Willi
p((. The internal source IP to use in a tunnel, also known as [[VirtualIp|virtual IP]].
503 58 Tobias Brunner
     If the value is one of the synonyms _%config_, _%cfg_, _%modeconfig_ or _%modecfg_, an address (from
504 58 Tobias Brunner
     the tunnel address family) is requested from the peer.
505 58 Tobias Brunner
     Since [[5.0.1]] a comma-separated list is accepted to request multiple addresses, and with _%config4_ and
506 58 Tobias Brunner
     _%config6_ an address of the given address family will be requested explicitly.
507 58 Tobias Brunner
     If an IP address is configured, it will be requested from the responder, which is free to respond with a
508 31 Martin Willi
     different address.
509 23 Tobias Brunner
510 57 Tobias Brunner
_rightsourceip = %config | <network>/<netmask> | %poolname_
511 7 Martin Willi
512 23 Tobias Brunner
p((. The internal source IP to use in a tunnel for the remote peer. If the value is %config on the responder
513 31 Martin Willi
     side, the initiator must propose an address which is then echoed back. Also supported are address pools
514 58 Tobias Brunner
     expressed as _<network>/<netmask>_ or the use of an external IP address pool using _%%poolname_ where
515 58 Tobias Brunner
     _poolname_ is the name of the IP address pool used for the lookup (see [[VirtualIp|virtual IP]] for details).
516 1 Martin Willi
     Since [[5.0.1]] a comma-separated list of IP addresses / pools is accepted, for instance, to define pools of
517 58 Tobias Brunner
     different address families. 
518 57 Tobias Brunner
519 67 Tobias Brunner
_left|rightsubnet = <ip subnet>![[<proto/port>]][,...]_
520 1 Martin Willi
521 1 Martin Willi
p((. private subnet behind the left participant, expressed as network/netmask; if omitted, essentially assumed
522 1 Martin Willi
     to be _left_/32|128, signifying that the _left|right_ end of the connection goes to the _left|right_ participant only.
523 1 Martin Willi
     The configured subnets of the peers may differ, the protocol narrows it to the greatest common subnet.
524 57 Tobias Brunner
     Since [[5.0.0]] this is also done for IKEv1, but as this may lead to problems with other implementations,
525 58 Tobias Brunner
     make sure to configure identical subnets in such configurations.
526 58 Tobias Brunner
     IKEv2 supports multiple subnets separated by commas, IKEv1 only interprets the first subnet of such a definition,
527 58 Tobias Brunner
     unless the Cisco Unity extension plugin is enabled (available since [[5.0.1]]). 
528 58 Tobias Brunner
529 1 Martin Willi
p((. Since [[5.1.0]] the optional part after each subnet enclosed in square brackets specifies a protocol/port to restrict
530 1 Martin Willi
     the selector for that subnet. *Examples:* leftsubnet=[tcp/http],[6/80] or leftsubnet=fec1::1[udp],[/53].
531 70 Tobias Brunner
     Instead of omitting either value _%any_ can be used to the same effect, e.g. leftsubnet=fec1::1[udp/%any],[%any/53].
532 70 Tobias Brunner
533 70 Tobias Brunner
p((. Since [[5.1.1]], if the protocol is _icmp_ or _ipv6-icmp_ the port is interpreted as ICMP message type if it is less than 256,
534 70 Tobias Brunner
     or as type and code if it greater or equal to 256, with the type in the most significant 8 bits and the code in the
535 70 Tobias Brunner
     least significant 8 bits.
536 67 Tobias Brunner
537 67 Tobias Brunner
p((. The port value can alternatively take the value _%opaque_ for RFC 4301 OPAQUE selectors, or a numerical range
538 67 Tobias Brunner
     in the form 1024-65535. None of the kernel backends currently supports opaque or port ranges and uses _%any_
539 67 Tobias Brunner
     for policy installation instead.
540 67 Tobias Brunner
541 67 Tobias Brunner
p((. Instead of specifying a subnet, _%dynamic_ can be used to replace it with the IKE address, having the same effect
542 67 Tobias Brunner
     as omitting _left|rightsubnet_ completely. Using _%dynamic_ can be used to define multiple dynamic selectors,
543 67 Tobias Brunner
     each having a potentially different protocol/port definition.
544 23 Tobias Brunner
545 21 Andreas Steffen
_left|rightupdown = <path>_
546 1 Martin Willi
547 31 Martin Willi
p((. what _updown_ script to run to adjust routing and/or firewalling when the status of the connection
548 1 Martin Willi
     changes (default _ipsec _updown_). Relevant only locally, other end need not agree on it.
549 33 Tobias Brunner
     Charon uses the _updown_ script to insert firewall rules only, since routing has been implemented directly
550 33 Tobias Brunner
     into the daemon.
551 33 Tobias Brunner
552 33 Tobias Brunner
h2. IKEv2 Mediation Extension Parameters
553 33 Tobias Brunner
554 33 Tobias Brunner
The following parameters are relevant to IKEv2 Mediation Extension operation only.
555 33 Tobias Brunner
556 23 Tobias Brunner
_mediation = yes | *no*_
557 23 Tobias Brunner
558 31 Martin Willi
p((. whether this connection is a mediation connection,  ie.  whether this connection is used to mediate other
559 57 Tobias Brunner
     connections.  Mediation connections create no child SA. Acceptable values  are  no (the default) and yes.
560 57 Tobias Brunner
561 57 Tobias Brunner
_mediated_by = <name>_
562 57 Tobias Brunner
563 57 Tobias Brunner
p((. the  name  of the connection to mediate this connection through. If given, the connection will  be  mediated
564 21 Andreas Steffen
     through  the  named mediation  connection.  The mediation connection must set *mediation=yes*.
565 1 Martin Willi
566 31 Martin Willi
_me_peerid = <id>_
567 1 Martin Willi
568 57 Tobias Brunner
p((. ID as which the peer is known to the mediation server, ie. which the  other end of this connection uses as
569 1 Martin Willi
     its leftid on its connection to the mediation server.  This is the ID we request  the mediation server to
570 1 Martin Willi
     mediate us with.  If me_peerid is not given, the rightid of this connection will be used as peer ID.
571 58 Tobias Brunner
572 58 Tobias Brunner
h2. Removed parameters (since 5.0.0)
573 58 Tobias Brunner
574 58 Tobias Brunner
_auth = *esp* | ah_
575 58 Tobias Brunner
576 58 Tobias Brunner
p((. whether authentication should be done as part of ESP encryption, or separately using the AH protocol.
577 58 Tobias Brunner
	Only supported by the IKEv1 daemon pluto.
578 58 Tobias Brunner
579 69 Tobias Brunner
p((. Since [[5.1.1]] the *ah* keyword can be used to configure AH with the charon IKE daemon.
580 69 Tobias Brunner
581 58 Tobias Brunner
_pfs = *yes* | no_
582 58 Tobias Brunner
583 58 Tobias Brunner
p((. whether _Perfect Forward Secrecy_ of keys is desired on the connection's keying channel (with PFS,
584 58 Tobias Brunner
     penetration of the key-exchange protocol does not compromise keys negotiated earlier). IKEv2 always uses
585 58 Tobias Brunner
     PFS for IKE_SA rekeying whereas for CHILD_SA rekeying PFS is enforced by defining a Diffie-Hellman dhgroup
586 58 Tobias Brunner
     in the _esp_ parameter.  Since [[5.0.0]] the latter also applies to IKEv1 and this parameter has no effect anymore.
587 58 Tobias Brunner
588 58 Tobias Brunner
_pfsgroup = <modp group>_
589 58 Tobias Brunner
590 58 Tobias Brunner
p((. defines a Diffie-Hellman group for _perfect forward secrecy_ in IKEv1 Quick Mode differing from the DH group
591 58 Tobias Brunner
     used for IKEv1 Main Mode (IKEv1 pluto daemon only).
592 58 Tobias Brunner
593 58 Tobias Brunner
_left|rightnexthop = %direct | %defaultroute | <ip address> | <fqdn>_
594 58 Tobias Brunner
595 58 Tobias Brunner
p((. This parameter is usually not needed any more because the NETKEY IPsec stack does not require
596 58 Tobias Brunner
     explicit routing entries for the traffic to be tunneled. If _left|sourceip_ is used with IKEv1
597 58 Tobias Brunner
     then _left|rightnexthop_ must still be set in order for the source routes to work properly.
598 58 Tobias Brunner
599 58 Tobias Brunner
_left|rightsubnetwithin = <ip subnet>_
600 58 Tobias Brunner
601 58 Tobias Brunner
p((. the  peer can propose any subnet or single IP address that fits within the range defined by
602 58 Tobias Brunner
     _left|rightsubnetwithin_.  Is a synonym for _left|rightsubnet_ since [[5.0.0]], as subnets are narrowed.