-.TH IPSEC.CONF 5 "27 Jun 2007"
+.TH IPSEC.CONF 5 "2010-05-30"
.SH NAME
ipsec.conf \- IPsec configuration and connections
.SH DESCRIPTION
file
specifies most configuration and control information for the
strongSwan IPsec subsystem.
-(The major exception is secrets for authentication;
+The major exception is secrets for authentication;
see
-.IR ipsec.secrets (5).)
+.IR ipsec.secrets (5).
Its contents are not security-sensitive.
.PP
The file is a text file, consisting of one or more
.I 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.)
+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.
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
-'IKE SA' in the IKEv2 protocol. That what is being negotiated, the kernel
-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.
+The path to control the connection is called 'ISAKMP SA' in IKEv1
+and 'IKE SA' in the IKEv2 protocol. That what is being negotiated, the kernel
+level data path, is called 'IPsec SA' or 'Child SA'.
+strongSwan currently uses two separate keying daemons. \fIpluto\fP handles
+all IKEv1 connections, \fIcharon\fP is the daemon handling the IKEv2
+protocol.
.PP
To avoid trivial editing of the configuration file to suit it to each system
involved in a connection,
or
.I right
is arbitrary;
-IPsec figures out which one it is being run on based on internal information.
+for every connection description an attempt is made to figure out whether
+the local endpoint should act as the
+.I left
+or
+.I right
+endpoint. This is done by matching the IP addresses defined for both endpoints
+with the IP addresses assigned to local network interfaces. If a match is found
+then the role (left or right) that matches is going to be considered local.
+If no match is found during startup,
+.I left
+is considered local.
This permits using identical connection specifications on both ends.
There are cases where there is no symmetry; a good convention is to
use
.B esp
(the default) and
.BR ah .
-The IKEv2 daemon currently supports only ESP.
+.br
+The IKEv2 daemon currently supports ESP only.
.TP
.B authby
how the two security gateways should authenticate each other;
.B xauthrsasig
that will enable eXtended AUTHentication (XAUTH) in addition to IKEv1 main mode
based on shared secrets or digital RSA signatures, respectively.
+IKEv2 additionally supports the value
+.BR eap ,
+which indicates an initiator to request EAP authentication. The EAP method
+to use is selected by the server (see
+.BR eap ).
This parameter is deprecated for IKEv2 connections, as two peers do not need
to agree on an authentication method. Use the
.B leftauth
.B auto
what operation, if any, should be done automatically at IPsec startup;
currently-accepted values are
-.B add
-,
-.B route
-,
+.BR add ,
+.BR route ,
.B start
and
-.BR ignore .
+.B ignore
+(the default).
.B add
loads a connection without starting it.
.B route
.B no
prevents IPsec from proposing compression;
a proposal to compress will still be accepted.
-IKEv2 does not support IP compression yet.
.TP
.B dpdaction
controls the use of the Dead Peer Detection protocol (DPD, RFC 3706) where
and
.B restart
all activate DPD. If no activity is detected, all connections with a dead peer
-are stopped and unrouted (
-.B clear
-), put in the hold state (
-.B hold
-) or restarted (
-.B restart
-).
+are stopped and unrouted
+.RB ( clear ),
+put in the hold state
+.RB ( hold )
+or restarted
+.RB ( restart ).
For IKEv1, the default is
.B none
which disables the active sending of R_U_THERE notifications.
wants to use DPD. For IKEv2,
.B none
does't make sense, since all messages are used to detect dead peers. If specified,
-it has the same meaning as the default (
-.B clear
-).
+it has the same meaning as the default
+.RB ( clear ).
.TP
.B dpddelay
defines the period time interval with which R_U_THERE messages/INFORMATIONAL
.TP
.B eap
defines the EAP type to propose as server if the client requests EAP
-authentication. This parameter is deprecated in the favour of
+authentication. Currently supported values are
+.B aka
+for EAP-AKA,
+.B gtc
+for EAP-GTC,
+.B md5
+for EAP-MD5,
+.B mschapv2
+for EAP-MS-CHAPv2,
+.B radius
+for the EAP-RADIUS proxy and
+.B sim
+for EAP-SIM. Additionally, IANA assigned EAP method numbers are accepted, or a
+definition in the form
+.B eap=type-vendor
+(e.g. eap=7-12345) can be used to specify vendor specific EAP types.
+This parameter is deprecated in the favour of
.B leftauth.
To forward EAP authentication to a RADIUS server using the EAP-RADIUS plugin,
set
-.B eap=radius
+.BR eap=radius .
.TP
.B 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
.B %identity
-uses the EAP Identity method to ask the client for a EAP identity. If not
+uses the EAP Identity method to ask the client for an EAP identity. If not
defined, the IKEv2 identity will be used as EAP identity.
.TP
.B esp
-ESP encryption/authentication algorithm to be used
+comma-separated list of ESP encryption/authentication algorithms to be used
for the connection, e.g.
-.B 3des-md5
-(encryption-integrity-[dh-group]). If dh-group is specified, CHILD_SA setup
-and rekeying include a separate diffe hellman exchange (IKEv2 only).
+.BR 3des-md5 .
+The notation is
+.BR encryption-integrity-[dh-group] .
+.br
+If
+.B dh-group
+is specified, CHILD_SA setup and rekeying include a separate diffe hellman
+exchange (IKEv2 only).
.TP
.B 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
+This may help to surmount restrictive firewalls. In order to force the peer to
encapsulate packets, NAT detection payloads are faked (IKEv2 only).
.TP
.B ike
-IKE/ISAKMP SA encryption/authentication algorithm to be used, e.g.
-.B aes128-sha1-modp2048
-(encryption-integrity-dhgroup). In IKEv2, multiple algorithms and proposals
-may be included, such as
+comma-separated list of IKE/ISAKMP SA encryption/authentication algorithms
+to be used, e.g.
+.BR aes128-sha1-modp2048 .
+The notation is
+.BR encryption-integrity-dhgroup .
+In IKEv2, multiple algorithms and proposals may be included, such as
.B aes128-aes256-sha1-modp1536-modp2048,3des-sha1-md5-modp1024.
.TP
.B ikelifetime
-how long the keying channel of a connection ('ISAKMP/IKE SA')
+how long the keying channel of a connection (ISAKMP or IKE SA)
should last before being renegotiated.
.TP
.B 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
+charon daemon for a given connection. Allows peaceful cooperation e.g. with
the Mobile IPv6 daemon mip6d who wants to control the kernel policies.
Acceptable values are
.B yes
.B keyexchange
setting. The default value
.B ike
-currently behaves exactly as
-.B ikev1.
+currently is a synonym for
+.BR ikev1 .
.TP
.B keyingtries
how many attempts (a whole number or \fB%forever\fP) should be made to
.TP
.B left
(required)
-the IP address of the left participant's public-network interface,
-in any form accepted by
-.IR ttoaddr (3)
+the IP address of the left participant's public-network interface
or one of several magic values.
If it is
.BR %defaultroute ,
.B left
will be filled in automatically with the local address
-of the default-route interface (as determined at IPsec startup time).
-(Either
+of the default-route interface (as determined at IPsec startup time and
+during configuration update).
+Either
.B left
or
.B right
may be
.BR %defaultroute ,
-but not both.)
-The value
-.B %any
-signifies an address to be filled in (by automatic keying) during
-negotiation. The prefix
+but not both.
+The prefix
.B %
in front of a fully-qualified domain name or an IP address will implicitly set
.B leftallowany=yes.
-If the domain name cannot be resolved into an IP address at IPsec startup or update time
-then
+If the domain name cannot be resolved into an IP address at IPsec startup or
+update time then
.B left=%any
and
.B leftallowany=no
will be assumed.
+
+In case of an IKEv2 connection, the value
+.B %any
+for the local endpoint signifies an address to be filled in (by automatic
+keying) during negotiation. If the local peer initiates the connection setup
+the routing table will be queried to determine the correct local IP address.
+In case the local peer is responding to a connection setup then any IP address
+that is assigned to a local interface will be accepted.
+.br
+Note that specifying
+.B %any
+for the local endpoint is not supported by the IKEv1 pluto daemon.
+
+If
+.B %any
+is used for the remote endpoint it literally means any IP address.
+
+Please note that with the usage of wildcards multiple connection descriptions
+might match a given incoming connection attempt. The most specific description
+is used in that case.
.TP
.B leftallowany
a modifier for
, making it behave as
.B %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.
+Recommended for dynamic IP addresses that can be resolved by DynDNS at IPsec
+startup or update time.
Acceptable values are
.B yes
and
(the default).
.TP
.B leftauth
-Authentication method to use (local) or require (remote) in this connection.
+Authentication method to use locally (left) or require from the remote (right)
+side.
This parameter is supported in IKEv2 only. Acceptable values are
.B pubkey
for public key authentication (RSA/ECDSA),
of
.B eap,
an optional EAP method can be appended. Currently defined methods are
-.B eap-aka, eap-sim, eap-gtc, eap-md5
+.BR eap-aka ,
+.BR eap-gtc ,
+.BR eap-md5 ,
+.B eap-mschapv2
and
-.B eap-mschapv2.
+.BR eap-sim .
Alternatively, IANA assigned EAP method numbers are accepted. Vendor specific
EAP methods are defined in the form
.B eap-type-vendor
-(e.g.
-.B eap-7-12345
-).
+.RB "(e.g. " eap-7-12345 ).
.TP
.B leftauth2
Same as
-.B leftauth,
+.BR 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
but for the second authentication round (IKEv2 only).
.TP
.B 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.
+the path to the left participant's X.509 certificate. The file can be encoded
+either in PEM or DER format. OpenPGP certificates are supported as well.
Both absolute paths or paths relative to \fI/etc/ipsec.d/certs\fP
are accepted. By default
.B leftcert
.B 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 \fI/etc/ipsec.d/acerts/\fP thas has been
-issued to the peer by a trusted Authorization Authority stored in
-\fI/etc/ipsec.d/aacerts/\fP. Attribute certificates are not supported in IKEv2 yet.
+by a valid attribute certificate stored in \fI/etc/ipsec.d/acerts/\fP thas has
+been issued to the peer by a trusted Authorization Authority stored in
+\fI/etc/ipsec.d/aacerts/\fP.
+.br
+Attribute certificates are not supported in IKEv2 yet.
.TP
.B lefthostaccess
inserts a pair of INPUT and OUTPUT iptables rules using the default
(the default).
.TP
.B leftid
-how
-the left participant
-should be identified for authentication;
+how the left participant should be identified for authentication;
defaults to
.BR left .
-Can be an IP address (in any
-.IR ttoaddr (3)
-syntax)
-or a fully-qualified domain name preceded by
+Can be an IP address or a fully-qualified domain name preceded by
.B @
(which is used as a literal string and not resolved).
.TP
.TP
.B 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
+IKEv2 connections only. If unspecified, port 500 is used with the port floating
+to 4500 if a NAT is detected or MOBIKE is enabled. Specifying a local IKE port
different from the default additionally requires a socket implementation that
listens to this port.
.TP
.B 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.
+this parameter is usually not needed any more because the NETKEY IPsec stack
+does not require explicit routing entries for the traffic to be tunneled. If
+.B leftsourceip
+is used with IKEv1 then
+.B leftnexthop
+must still be set in order for the source routes to work properly.
.TP
.B leftprotoport
restrict the traffic selector to a single protocol and/or port.
or
.BR yes ,
and
-.BR ifasked .
+.BR ifasked ,
+the latter meaning that the peer must send a certificate request payload in
+order to get a certificate in return.
.TP
.B leftsourceip
The internal source IP to use in a tunnel, also known as virtual IP. If the
-value is
+value is one of the synonyms
.BR %modeconfig ,
.BR %modecfg ,
.BR %config ,
or
-.B %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.
+.BR %cfg ,
+an address is requested from the peer. In IKEv2, a statically defined address
+is also requested, since the server may change it.
.TP
.B rightsourceip
The internal source IP to use in a tunnel for the remote peer. If the
value is
.B %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
+on the responder side, the initiator must propose an address which is then
+echoed back. Also supported are address pools expressed as
\fInetwork\fB/\fInetmask\fR
-or the use of an external IP address pool using %\fIpoolname\fR
-, where \fIpoolname\fR is the name of the IP address pool used for the lookup.
+or the use of an external IP address pool using %\fIpoolname\fR,
+where \fIpoolname\fR is the name of the IP address pool used for the lookup.
.TP
.B leftsubnet
private subnet behind the left participant, expressed as
-\fInetwork\fB/\fInetmask\fR
-(actually, any form acceptable to
-.IR ttosubnet (3));
+\fInetwork\fB/\fInetmask\fR;
if omitted, essentially assumed to be \fIleft\fB/32\fR,
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
.IR 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.
+script to insert firewall rules only, since routing has been implemented
+directly into charon.
.TP
.B lifebytes
the number of bytes transmitted over an IPsec SA before it expires (IKEv2
.B pull
(the default).
Currently relevant for IKEv1 only since IKEv2 always uses the configuration
-payload in pull mode.
+payload in pull mode. Cisco VPN gateways usually operate in
+.B push
+mode.
.TP
.B pfs
whether Perfect Forward Secrecy of keys is desired on the connection's
.BR no .
The two ends need not agree, but while a value of
.B no
-prevents Pluto/Charon from requesting renegotiation,
+prevents pluto/charon from requesting renegotiation,
it does not prevent responding to renegotiation requested from the other end,
so
.B no
signifying that packets should be discarded; and
.BR reject ,
signifying that packets should be discarded and a diagnostic ICMP returned.
-Charon currently supports
+The IKEv2 daemon charon currently supports
.BR tunnel ,
.BR transport ,
and
.BR tunnel_proxy
-connection types, only .
+connection types, only.
.TP
.B xauth
specifies the role in the XAUTH protocol if activated by
.SH "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.
+parameters to a Certification Authority (CA).
.TP 10
.B auto
currently can have either the value
.TP
.B ocspuri2
defines an alternative OCSP URI. Currently used by IKEv2 only.
+.TP
.B 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
.B config
section known to the IPsec software is the one named
.BR setup ,
-which contains information used when the software is being started
-(see
-.IR starter (8)).
+which contains information used when the software is being started.
Here's an example:
.PP
.ne 8
.B overridemtu
value that the MTU of the ipsec\fIn\fR interface(s) should be set to,
overriding IPsec's (large) default.
-.SH CHOOSING A CONNECTION
-.PP
-When choosing a connection to apply to an outbound packet caught with a
-.BR %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.
-.PP
-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.
.SH FILES
.nf
/etc/ipsec.conf
/etc/ipsec.d/crls
.SH SEE ALSO
-ipsec(8), pluto(8), starter(8), ttoaddr(3), ttodata(3)
+ipsec(8), pluto(8), starter(8)
.SH 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.
+Originally written for the FreeS/WAN project by Henry Spencer.
+Updated and extended for the strongSwan project <http://www.strongswan.org> by
+Tobias Brunner, Andreas Steffen and Martin Willi.
.SH BUGS
.PP
If conns are to be added before DNS is available, \fBleft=\fP\fIFQDN\fP
projects / strongswan.git / commitdiff