+++ /dev/null
- ----------------------------
- strongSwan - Configuration
- ----------------------------
-
-
-Contents
---------
-
- 1. Overview
- 2. Quickstart
- 2.1 Site-to-Site case
- 2.2 Host-to-Host case
- 2.3 Four Tunnel case
- 2.4 Four Tunnel case the elegant way with source routing
- 2.5 Roadwarrior case
- 2.6 Roadwarrior case with virtual IP
- 3. Generating X.509 certificates and CRLs with OpenSSL
- 3.1 Generating a CA certificate
- 3.2 Generating a host or user certificate
- 3.3 Generating a CRL
- 3.4 Revoking a certificate
- 4. Configuring the connections - ipsec.conf
- 4.1 Configuring my side
- 4.2 Multiple certificates
- 4.3 Configuring the peer side using CA certificates
- 4.4 Handling Virtual IPs and wildcard subnets
- 4.5 Protocol and port selectors
- 4.6 IPsec policies based on wildcards
- 4.7 IPsec policies based on CA certificates
- 4.8 Sending certificate requests
- 4.9 IPsec policies based on group attributes
- 5. Configuring certificates and CRLs
- 5.1 Installing CA certificates
- 5.2 Installing optional Certificate Revocation Lists (CRLs)
- 5.3 Dynamic update of certificates and CRLs
- 5.4 Local caching of CRLs
- 5.5 Online Certificate Status Protocol (OCSP)
- 5.6 CRL policy
- 5.7 Configuring the peer side using locally stored certificates
- 6. Configuring the private keys - ipsec.secrets
- 6.1 Loading private key files in PKCS#1 format
- 6.2 Entering passphrases interactively
- 6.3 Multiple private keys
- 7. Configuring CA properties - ipsec.conf
- 8. Smartcard support
- 8.1 Configuring a smartcard-based connection
- 8.2 Entering the PIN code
- 8.3 PIN-pad equipped smartcard readers
- 8.4 Configuring a smartcard using pkcs15-init
- 8.5 PKCS#1 proxy functions
- 9. Configuring the clients
- 9.1 strongSwan
- 9.2 PGPnet
- 9.3 Safenet/Soft-Remote
- 9.4 SSH Sentinel
- 9.5 Windows 2000/XP
- 10. Monitoring functions
- 11. Firewall support functions
- 11.1 Environment variables in the updown script
- 11.2 Automatic insertion and deletion of iptables firewall rules
- 11.3 Sample Linux 2.6 _updown_espmark script for iptables < 1.3.5
- 12. Authentication with raw RSA public keys
- 13. Authentication with OpenPGP certificates
- 13.1 OpenPGP certificates
- 13.2 OpenPGP private keys
- 13.3 Monitoring functions
- 13.4 Suppression of certificate request messages
- 14. Additional features
- 14.1 Authentication and encryption algorithms
- 14.2 NAT traversal
- 14.3 Dead peer detection
- 14.4 IKE Mode Config Pull Mode
- 14.5 IKE Mode Config Push Mode
- 14.6 XAUTH - Extended Authentication (NEW)
- 15. Copyright statement and acknowledgements
-
-
-1. Overview
- --------
-
-strongSwan is an OpenSource IPsec solution for the Linux operating system
-and currently supports the following features:
-
- * runs both on Linux 2.4 (KLIPS) and Linux 2.6 (native IPsec) kernels.
-
- * strong 3DES, AES, Serpent, Twofish, or Blowfish encryption.
-
- * Authentication based on X.509 certificates or preshared secrets.
-
- * IPsec policies based on wildcards or intermediate CAs.
-
- * Powerful and flexible IPsec policies based on group attributes.
-
- * Retrieval of Certificate Revocation Lists (CRLs) via HTTP or LDAP.
-
- * Local caching of fetched CRLs
-
- * Full support of the Online Certificate Status Protocol (OCSP, RFC 2560).
-
- * CA management functions including OCSP and CRL URIs and default LDAP server.
-
- * Optional storage of RSA private keys on smartcards or USB crypto tokens
-
- * Standardized PKCS#11 interface with optional proxy functions serving
- external applications (disc encryption, etc.).
-
- * NAT-Traversal (RFC 3947)
-
- * Support of Virtual IPs via static configuration and IKE Mode Config
-
- * XAUTH client and server functionality in conjunction with either PSK
- or RSA IKE Main Mode authentication.
-
- * Support of Delete SA and informational Notification messages.
-
- * Dead Peer Detection (DPD, RFC 3706)
-
-Compatibility has successfully been tested with peers running the following
-IPsec clients:
-
- FreeS/WAN, Openswan, SafeNet/SoftRemote, NCP Secure Entry Client,
- SonicWALL Global VPN Client, The GreenBow, Microsoft Windows 2000/XP, etc.
-
-Furthermore, interoperability with the following VPN gateways
-has been demonstrated during the IPsec 2001 Conference in Paris:
-
- Cisco IOS Routers, Cisco PIX firewall, Cisco VPN3000,
- Nortel Contivity VPN Switch, NetScreen (FreeS/WAN as responder only),
- OpenBSD with isakmpd, Netasq, Netcelo, and 6WIND.
-
-Potentially any IPsec implementation with X.509 certificate support can
-be made to cooperate with strongSwan. The latest addition has been the successful
-interoperability with the Check Point VPN-1 NG gateway.
-
-
-2. Quickstart
- ----------
-
-In the following examples we assume for reasons of clarity that left designates
-the local host and that right is the remote host. Certificates for users, hosts
-and gateways are issued by a ficticious strongSwan CA. How to generate private keys
-and certificates using OpenSSL will be explained in section 3. The CA certificate
-"strongswanCert.pem" must be present on all VPN end points in order to be able to
-authenticate the peers.
-
-
-2.1 Site-to-site case
- -----------------
-
-In this scenario two security gateways moon and sun will connect the
-two subnets moon-net and sun-net with each other through a VPN tunnel
-set up between the two gateways:
-
- 10.1.0.0/16 -- | 192.168.0.1 | === | 192.168.0.2 | -- 10.2.0.0/16
- moon-net moon sun sun-net
-
-Configuration on gateway moon:
-
- /etc/ipsec.d/cacerts/strongswanCert.pem
-
- /etc/ipsec.d/certs/moonCert.pem
-
- /etc/ipsec.secrets:
-
- : RSA moonKey.pem "<optional passphrase>"
-
- /etc/ipsec.conf:
-
- conn net-net
- left=%defaultroute
- leftsubnet=10.1.0.0/16
- leftcert=moonCert.pem
- right=192.168.0.2
- rightsubnet=10.2.0.0/16
- rightid="C=CH, O=Linux strongSwan, CN=sun.strongswan.org"
- auto=start
-
-Configuration on gateway sun:
-
- /etc/ipsec.d/cacerts/strongswanCert.pem
-
- /etc/ipsec.d/certs/sunCert.pem
-
- /etc/ipsec.secrets:
-
- : RSA sunKey.pem "<optional passphrase>"
-
- /etc/ipsec.conf:
-
- conn net-net
- left=%defaultroute
- leftsubnet=10.2.0.0/16
- leftcert=sunCert.pem
- right=192.168.0.1
- rightsubnet=10.1.0.0/16
- rightid="C=CH, O=Linux strongSwan, CN=moon.strongswan.org"
- auto=start
-
-
-2.2 Host-to-host case
- -----------------
-
-This is a setup between two single hosts which don't have a subnet behind
-them. Although IPsec transport mode would be sufficient for host-to-host
-connections we will use the default IPsec tunnel mode.
-
- | 192.168.0.1 | === | 192.168.0.2 |
- moon sun
-
-Configuration on host moon:
-
- /etc/ipsec.d/cacerts/strongswanCert.pem
-
- /etc/ipsec.d/certs/moonCert.pem
-
- /etc/ipsec.secrets:
-
- : RSA moonKey.pem "<optional passphrase>"
-
- /etc/ipsec.conf:
-
- conn host-host
- left=%defaultroute
- leftcert=moonCert.pem
- right=192.168.0.2
- rightid="C=CH, O=Linux strongSwan, CN=sun.strongswan.org"
- auto=start
-
-Configuration on host sun:
-
- /etc/ipsec.d/cacerts/strongswanCert.pem
-
- /etc/ipsec.d/certs/sunCert.pem
-
- /etc/ipsec.secrets:
-
- : RSA sunKey.pem "<optional passphrase>"
-
- /etc/ipsec.conf:
-
- conn host-host
- left=%defaultroute
- leftcert=sunCert.pem
- right=192.168.0.1
- rightid="C=CH, O=Linux strongSwan, CN=moon.strongswan.org"
- auto=start
-
-
-2.3 Four Tunnel case
- ----------------
-
-In a site-to-site setup a system administrator logged into the local gateway
-often would like to access the peer gateway or a server in the subnet behind
-the peer gateway over a secure IPsec tunnel.Since IP packets leaving a gateway
-via the outer network interface carry the IP address of this NIC, four IPsec
-Security Associations (SAs) must be set up to achieve full connectivity. The
-example below shows how this can be done without much additional typing work ,
-using the "also" macro which includes connection definitions defined farther
-down in the ipsec.conf file.
-
- 10.1.0.0/16 -- | 192.168.0.1 | === | 192.168.0.2 | -- 10.2.0.0/16
- moon-net moon sun sun-net
-
-Configuration on gateway moon:
-
- /etc/ipsec.d/cacerts/strongswanCert.pem
-
- /etc/ipsec.d/certs/moonCert.pem
-
- /etc/ipsec.secrets:
-
- : RSA moonKey.pem "<optional passphrase>"
-
- /etc/ipsec.conf:
-
- conn net-net
- leftsubnet=10.1.0.0/16
- rightsubnet=10.2.0.0/16
- also host-host
-
- conn net-host
- leftsubnet=10.1.0.0/16
- also host-host
-
- conn host-net
- rightsubnet=10.2.0.0/16
- also host-host
-
- conn host-host
- left=%defaultroute
- leftcert=moonCert.pem
- right=192.168.0.2
- rightid="C=CH, O=Linux strongSwan, CN=sun.strongswan.org"
- auto=start
-
-Configuration on gateway sun:
-
- /etc/ipsec.d/cacerts/strongswanCert.pem
-
- /etc/ipsec.d/certs/sunCert.pem
-
- /etc/ipsec.secrets:
-
- : RSA sunKey.pem "<optional passphrase>"
-
- /etc/ipsec.conf:
-
- conn net-net
- leftsubnet=10.2.0.0/16
- rightsubnet=10.1.0.0/16
- also=host-host
-
- conn net-host
- leftsubnet=10.2.0.0/16
- also=host-host
-
- conn host-net
- rightsubnet=10.1.0.0/16
- also=host-host
-
- conn host-host
- left=%defaultroute
- leftcert=sunCert.pem
- right=192.168.0.1
- rightid="C=CH, O=Linux strongSwan, CN=moon.strongswan.org"
- auto=start
-
-
-2.4 The four tunnel case the elegant way with source routing
- --------------------------------------------------------
-
-As you certainly agree, the full four tunnel case described in the previous
-section becomes quite complex. If we could force the source address of the
-IP packets leaving the gateway through the outer interface to take on the
-IP address of the inner interface then we could use the single subnet-to-subnet
-tunnel from section 2.1. Such a setup becomes possible if we use the
-source routing capabilites of the ip route command that is already used
-by strongSwan's updown scripts.
-
- 10.1.0.0/16 -- | 192.168.0.1 | === | 192.168.0.2 | -- 10.2.0.0/16
- moon-net moon sun sun-net
-
-If we assume that the inner IP address of gateway moon is 10.1.0.1
-and the inner IP address of gateway sun is 10.2.0.1 then the
-insertion of the parameter
-
- leftsourceip=10.1.0.1
-
-in the connection definition of moon and
-
- leftsourceip=10.2.0.1
-
-on sun, respectively, will install source routing on both gateways.
-As a result the command
-
- ping 10.2.0.1
-
-executed on moon will leave the gateway with a source address of
-10.1.0.1 and will therefore take the net-net IPsec tunnel.
-
-Configuration on gateway moon:
-
- /etc/ipsec.d/cacerts/strongswanCert.pem
-
- /etc/ipsec.d/certs/moonCert.pem
-
- /etc/ipsec.secrets:
-
- : RSA moonKey.pem "<optional passphrase>"
-
- /etc/ipsec.conf:
-
- conn net-net
- left=%defaultroute
- leftsourceip=10.1.0.1
- leftsubnet=10.1.0.0/16
- leftcert=moonCert.pem
- right=192.168.0.2
- rightsubnet=10.2.0.0/16
- rightid="C=CH, O=Linux strongSwan, CN=sun.strongswan.org"
- auto=start
-
-Configuration on gateway sun:
-
- /etc/ipsec.d/cacerts/strongswanCert.pem
-
- /etc/ipsec.d/certs/sunCert.pem
-
- /etc/ipsec.secrets:
-
- : RSA sunKey.pem "<optional passphrase>"
-
- /etc/ipsec.conf:
-
- conn net-net
- left=%defaultroute
- leftsubnet=10.2.0.0/16
- leftsourceip=10.2.0.1
- leftcert=sunCert.pem
- right=192.168.0.1
- rightsubnet=10.1.0.0/16
- rightid="C=CH, O=Linux strongSwan, CN=moon.strongswan.org"
- auto=start
-
-
-2.5 Roadwarrior case
- ----------------
-
-This is a very common case where a strongSwan gateway serves an arbitrary number
-of remote VPN clients usually having dynamic IP addresses.
-
- 10.1.0.0/16 -- | 192.168.0.1 | === | x.x.x.x |
- moon-net moon carol
-
-Configuration on gateway moon:
-
- /etc/ipsec.d/cacerts/strongswanCert.pem
-
- /etc/ipsec.d/certs/moonCert.pem
-
- /etc/ipsec.secrets:
-
- : RSA moonKey.pem "<optional passphrase>"
-
- /etc/ipsec.conf:
-
- conn rw
- left=%defaultroute
- leftsubnet=10.1.0.0/16
- leftcert=moonCert.pem
- right=%any
- auto=add
-
-Configuration on roadwarrior carol:
-
- /etc/ipsec.d/cacerts/strongswanCert.pem
-
- /etc/ipsec.d/certs/carolCert.pem
-
- /etc/ipsec.secrets:
-
- : RSA carolKey.pem "<optional passphrase>"
-
- /etc/ipsec.conf:
-
- conn home
- left=%defaultroute
- leftcert=carolCert.pem
- right=192.168.0.1
- rightsubnet=10.1.0.0/16
- rightid="C=CH, O=Linux strongSwan, CN=moon.strongswan.org"
- auto=start
-
-
-2.6 Roadwarrior case with virtual IP
- --------------------------------
-
-Roadwarriors usually have dynamic IP addresses assigned by the ISP they are
-currently attached to. In order to simplify the routing from moon-net back
-to the remote access client carol it would be desirable if the roadwarrior had
-an inner IP address chosen from a pre-assigned pool.
-
- 10.1.0.0/16 -- | 192.168.0.1 | === | x.x.x.x | -- 10.3.0.1
- moon-net moon carol virtual IP
-
-This virtual IP address can be assigned to a strongSwan roadwarrior by adding
-the parameter
-
- leftsourceip=10.3.0.1
-
-to the roadwarrior's ipsec.conf. Of course the virtual IP of each roadwarrior
-must be distinct. In our example it is chosen from the address pool
-
- rightsubnetwithin=10.3.0.0/16
-
-which can be added to the gateway's ipsec.conf so that a single connection
-definition can handle multiple roadwarriors.
-
-Configuration on gateway moon:
-
- /etc/ipsec.d/cacerts/strongswanCert.pem
-
- /etc/ipsec.d/certs/moonCert.pem
-
- /etc/ipsec.secrets:
-
- : RSA moonKey.pem "<optional passphrase>"
-
- /etc/ipsec.conf:
-
- conn rw
- left=%defaultroute
- leftsubnet=10.1.0.0/16
- leftcert=moonCert.pem
- right=%any
- rightsubnetwithin=10.3.0.0/16
- auto=add
-
-Configuration on roadwarrior carol:
-
- /etc/ipsec.d/cacerts/strongswanCert.pem
-
- /etc/ipsec.d/certs/carolCert.pem
-
- /etc/ipsec.secrets:
-
- : RSA carolKey.pem "<optional passphrase>"
-
- /etc/ipsec.conf:
-
- conn home
- left=%defaultroute
- leftsourceip=10.3.0.1
- leftcert=carolCert.pem
- right=192.168.0.1
- rightsubnet=10.1.0.0/16
- rightid="C=CH, O=Linux strongSwan, CN=moon.strongswan.org"
- auto=start
-
-
-3. Generating certificates and CRLs with OpenSSL
- ---------------------------------------------
-
-This section is not a full-blown tutorial on how to use OpenSSL. It just lists
-a few points that are relevant if you want to generate your own certificates
-and CRLs for use with strongSwan.
-
-
-3.1 Generating a CA certificate
- ---------------------------
-
-The OpenSSL statement
-
- openssl req -x509 -days 1460 -newkey rsa:2048 \
- -keyout strongswanKey.pem -out strongswanCert.pem
-
-creates a 2048 bit RSA private key strongswanKey.pem and a self-signed CA
-certificate strongswanCert.pem with a validity of 4 years (1460 days).
-
- openssl x509 -in cert.pem -noout -text
-
-lists the properties of a X.509 certificate cert.pem. It allows you to verify
-whether the configuration defaults in openssl.cnf have been inserted correctly.
-
-If you prefer the CA certificate to be in binary DER format then the following
-command achieves this transformation:
-
- openssl x509 -in strongswanCert.pem -outform DER -out strongswanCert.der
-
-The directory /etc/ipsec.d/cacerts contains all required CA certificates either
-in binary DER or in base64 PEM format. Irrespective of the file suffix, Pluto
-"automagically" determines the correct format.
-
-
-3.2 Generating a host or user certificate
- -------------------------------------
-
-The OpenSSL statement
-
- openssl req -newkey rsa:1024 -keyout hostKey.pem \
- -out hostReq.pem
-
-generates a 1024 bit RSA private key hostKey.pem and a certificate request
-hostReq.pem which has to be signed by the CA.
-
-If you want to add a subjectAltName field to the host certificate you must edit
-the OpenSSL configuration file openssl.cnf and add the following line in the
-[ usr_cert ] section:
-
- subjectAltName=DNS:moon.strongswan.org
-
-if you want to identify the host by its Fully Qualified Domain Name (FQDN ), or
-
- subjectAltName=IP:192.168.0.1
-
-if you want the ID to be of type IPV4_ADDR. Of course you could include both
-ID types with
-
- subjectAltName=DNS:moon.strongswan.org,IP:192.168.0.1
-
-but the use of an IP address for the identification of a host should be
-discouraged anyway.
-
-For user certificates the appropriate ID type is USER_FQDN which can be
-specified as
-
- subjectAltName=email:carol@strongswan.org
-
-or if the user's e-mail address is part of the subject's distinguished name
-
- subjectAltName=email:copy
-
-Now the certificate request can be signed by the CA with the command
-
- openssl ca -in hostReq.pem -days 730 -out hostCert.pem -notext
-
-If you omit the -days option then the default_days value (365 days) specified
-in openssl.cnf is used. The -notext option avoids that a human readable
-listing of the certificate is prepended to the base64 encoded certificate
-body.
-
-If you want to use the dynamic CRL fetching feature described in section 4.7
-then you may include one or several crlDistributionPoints in your end
-certificates. This can be done in the [ usr_cert ] section of the openssl.cnf
-configuration file:
-
- crlDistributionPoints= @crl_dp
-
- [ crl_dp ]
-
- URI.1="http://crl.strongswan.org/strongswan.crl"
- URI.2="ldap://ldap.strongswan.org/cn=strongSwan Root CA, o=Linux strongSwan
- , c=CH?certificateRevocationList"
-
-If you have only a single http distribution point then the short form
-
- crlDistributionPoints="URI:http://crl.strongswan.org/strongswan.crl"
-
-also works. Due to a known bug in OpenSSL this notation fails with ldap URIs.
-
-Usually a Windows-based VPN client needs its private key, its host or
-user certificate, and the CA certificate. The most convenient way to load
-this information is to put everything into a PKCS#12 file:
-
- openssl pkcs12 -export -inkey carolKey.pem \
- -in carolCert.pem -name "carol" \
- -certfile strongswanCert.pem -caname "strongSwan Root CA" \
- -out carolCert.p12
-
-
-3.3 Generating a CRL
- ----------------
-
-An empty CRL that is signed by the CA can be generated with the command
-
- openssl ca -gencrl -crldays 15 -out crl.pem
-
-If you omit the -crldays option then the default_crl_days value (30 days)
-specified in openssl.cnf is used.
-
-If you prefer the CRL to be in binary DER format then this conversion
-can be achieved with
-
- openssl crl -in crl.pem -outform DER -out cert.crl
-
-The directory /etc/ipsec.d/crls contains all CRLs either in binary DER
-or in base64 PEM format. Irrespective of the file suffix, Pluto
-"automagically" determines the correct format.
-
-
-3.4 Revoking a certificate
- ----------------------
-
-A specific host certificate stored in the file host.pem is revoked with the
-command
-
- openssl ca -revoke host.pem
-
-Next the CRL file must be updated
-
- openssl ca -gencrl -crldays 60 -out crl.pem
-
-The content of the CRL file can be listed with the command
-
- openssl crl -in crl.pem -noout -text
-
-in the case of a base64 CRL, or alternatively for a CRL in DER format
-
- openssl crl -inform DER -in cert.crl -noout -text
-
-
-
-4. Configuring the connections - ipsec.conf
- ----------------------------------------
-
-4.1 Configuring my side
- -------------------
-
-Usually the local side is the same for all connections. Therefore it makes
-sense to put the definitions characterizing the strongSwan security gateway into
-the conn %default section of the configuration file /etc/ipsec.conf. If we
-assume throughout this document that the strongSwan security gateway is left and
-the peer is right then we can write
-
-conn %default
- # my side is left - the freeswan security gateway
- left=%defaultroute
- leftcert=moonCert.pem
- # load connection definitions automatically
- auto=add
-
-The X.509 certificate by which the strongSwan security gateway will authenticate
-itself by sending it in binary form to its peers as part of the Internet Key
-Exchange (IKE) is specified in the line
-
- leftcert=moonCert.pem
-
-The certificate can either be stored in base64 PEM-format or in the binary
-DER-format. Irrespective of the file suffix, Pluto "automagically" determines
-the correct format. Therefore
-
- leftcert=moonCert.der
-
-or
-
- leftcert=moonCert.cer
-
-would also be valid alternatives.
-
-When using relative pathnames as in the examples above, the certificate files
-must be stored in in the directory /etc/ipsec.d/certs. In order to distinguish
-strongSwan's own certificates from locally stored trusted peer certificates
-(see section 5.5 for details), they could also be stored in a subdirectory
-below /etc/ipsec.d/certs as e.g. in
-
- leftcert=mycerts/moonCert.pem
-
-Absolute pathnames are also possible as in
-
- leftcert=/usr/ssl/certs/moonCert.pem
-
-As an ID for the VPN gateway we recommend the use of a Fully Qualified Domain
-Name (FQDN) of the form
-
-conn rw
- right=%any
- leftid=@moon.strongswan.org
-
-Important: When an FQDN identifier is used it must be explicitly included as a
-so called subjectAltName of type dnsName (DNS:) in the certificate indicated
-by leftcert. For details on how to generate certificates with subjectAltNames,
-please refer to section 7.2.
-
-If you don't want to mess with subjectAltNames, you can use the certificate's
-Distinguished Name (DN) instead, which is an identifier of type DER_ASN1_DN
-and which can be written e.g. in the LDAP-type format
-
-conn rw
- right=%any
- leftid="C=CH, O=Linux strongSwan, CN=moon.strongswan.org"
-
-Since the subject's DN is part of the certificate, the leftid does not have to
-be declared explicitly. Thus the entry
-
-conn rw
- right=%any
-
-automatically assumes the subject DN of leftcert to be the host ID.
-
-
-4.2 Multiple certificates
- ---------------------
-
-strongSwan supports multiple local host certificates and corresponding
-RSA private keys:
-
-conn rw1
- right=%any
- rightid=@peer1.domain1
- leftcert=myCert1.pem
- # leftid is DN of myCert1
-
-conn rw2
- right=%any
- rightid=@peer2.domain2
- leftcert=myCert2.pem
- # leftid is DN of myCert2
-
-When peer1 initiates a connection then strongSwan will send myCert1 and will
-sign with myKey1 defined in /etc/ipsec.secrets (see section 6.2) whereas
-myCert2 and myKey2 will be used in a connection setup started from peer2.
-
-
-4.3 Configuring the peer side using CA certificates
- -----------------------------------------------
-
-Now we can proceed to define our connections. In many applications we might
-have dozens of mostly Windows-based road warriors connecting to a central
-strongSwan security gateway. The following most simple statement:
-
-conn rw
- right=%any
-
-defines the general roadwarrior case. The line right=%any literally means that
-any IPSec peer is accepted, regardless of its current IP source address and its
-ID, as long as the peer presents a valid X.509 certificate signed by a CA the
-strongSwan security gateway puts explicit trust in. Additionally the signature
-during IKE main mode gives proof that the peer is in possession of the private
-RSA key matching the public key contained in the transmitted certificate.
-
-The ID by which a peer is identifying itself during IKE main mode can by any of
-the ID types IPV4_ADDR, FQDN, USER_FQDN or DER_ASN1_DN. If one of the first
-three ID types is used, then the accompanying X.509 certificate of the peer
-must contain a matching subjectAltName field of the type ipAddress (IP:),
-dnsName (DNS:) or rfc822Name (email:), respectively. With the fourth type
-DER_ASN1_DN the identifier must completely match the subject field of the
-peer's certificate. One of the two possible representations of a
-Distinguished Name (DN) is the LDAP-type format
-
- rightid="C=CH, O=Linux strongSwan, CN=sun.strongswan.org"
-
-Additional whitespace can be added everywhere as desired since it will be
-automatically eliminated by the X.509 parser. An exception is the single
-whitespace between individual words , like e.g. in Linux strongSwan, which is
-preserved by the parser.
-
-The Relative Distinguished Names (RDNs) can alternatively be separated by a
-slash '/' instead of a comma ','
-
- rightid="/C=CH/O=Linux strongSwan/CN=sun.strongswan.org"
-
-This is the representation extracted from the certificate by the OpenSSL
-command line option
-
- openssl x509 -in sunCert.pem -noout -subject
-
-The following RDNs are supported by strongSwan
-
-+---------------------------------------------------+
-| DC Domain Component |
-|---------------------------------------------------|
-| C Country |
-|---------------------------------------------------|
-| ST State or province |
-|---------------------------------------------------|
-| L Locality or town |
-|---------------------------------------------------|
-| O Organisation |
-|---------------------------------------------------|
-| OU Organisational Unit |
-|---------------------------------------------------|
-| CN Common Name |
-|---------------------------------------------------|
-| ND NameDistinguisher, used with CN |
-|---------------------------------------------------|
-| N Name |
-|---------------------------------------------------|
-| G Given name |
-|---------------------------------------------------|
-| S Surname |
-|---------------------------------------------------|
-| I Initials |
-|---------------------------------------------------|
-| T Personal title |
-|---------------------------------------------------|
-| E E-mail |
-|---------------------------------------------------|
-| Email E-mail |
-|---------------------------------------------------|
-| emailAddress E-mail |
-|---------------------------------------------------|
-| SN Serial number |
-|---------------------------------------------------|
-| serialNumber Serial number |
-|---------------------------------------------------|
-| D Description |
-|---------------------------------------------------|
-| ID X.500 Unique Identifier |
-|---------------------------------------------------|
-| UID User ID |
-|---------------------------------------------------|
-| TCGID [Siemens] Trust Center Global ID |
-|---------------------------------------------------|
-| unstructuredName Unstructured Name |
-|---------------------------------------------------|
-| UN Unstructured Name |
-|---------------------------------------------------|
-| employeeNumber Employee Number |
-|---------------------------------------------------|
-| EN Employee Number |
-+---------------------------------------------------+
-
-With the roadwarrior connection definition listed above, an IPsec SA for
-the strongSwan security gateway moon.strongswan.org itself can be established.
-If any roadwarrior should be able to reach e.g. the two subnets 10.1.0.0/24
-and 10.1.3.0/24 behind the security gateway then the following connection
-definitions will make this possible
-
-conn rw1
- right=%any
- leftsubnet=10.1.0.0/24
-
-conn rw3
- right=%any
- leftsubnet=10.1.3.0/24
-
-If not all peers in possession of a X.509 certificate signed by a specific
-certificate authority shall be given access to the Linux security gateway,
-then either a subset of them can be barred by listing the serial numbers of
-their certificates in a certificate revocation list (CRL) as specified in
-section 5.2 or as an alternative, access can be controlled by explicitly
-putting a roadwarrior entry for each eligible peer into ipsec.conf:
-
-conn sun
- right=%any
- rightid=@sun.strongswan.org
-
-conn carol
- right=%any
- rightid=carol@strongswan.org
-
-conn dave
- right=%any
- rightid="C=CH, O=Linux strongSwan, CN=dave@strongswan.org"
-
-When the IP address of a peer is known to be stable, it can be specified as
-well. This entry is mandatory when the strongSwan host wants to act as the
-initiator of an IPSec connection.
-
-conn sun
- right=192.168.0.2
- rightid=@sun.strongswan.org
-
-conn carol
- right=192.168.0.100
- rightid=carol@strongswan.org
-
-conn dave
- right=192.168.0.200
- rightid="C=CH, O=Linux strongSwan, CN=dave@strongswan.org"
-
-conn venus
- right=192.168.0.50
-
-In the last example the ID types FQDN, USER_FQDN, DER_ASN1_DN and IPV4_ADDR,
-respectively, were used. Of course all connection definitions presented so far
-have included the lines in the conn %defaults section, comprising among other
-a left and leftcert entry.
-
-
-4.4 Handling Virtual IPs and wildcard subnets
- -----------------------------------------
-
-Often roadwarriors are behind NAT-boxes with IPsec passthrough, which causes
-the inner IP source address of an IPsec tunnel to be different from the
-outer IP source address usually assigned dynamically by the ISP.
-Whereas the varying outer IP address can be handled by the right=%any
-construct, the inner IP address or subnet must always be declared in a
-connection definition. Therefore for the three roadwarriors rw1 to rw3
-connecting to a strongSwan security gateway the following entries are
-required in /etc/ipsec.conf:
-
-conn rw1
- right=%any
- righsubnet=10.4.0.5/32
-
-conn rw2
- right=%any
- rightsubnet=10.4.0.47/32
-
-conn rw3
- right=%any
- rightsubnet=10.4.0.128/28
-
-With the wildcard parameter rightsubnetwithin these three entries can be
-reduced to the single connection definition
-
-conn rw
- right=%any
- rightsubnetwithin=10.4.0.0/24
-
-Any host will be accepted (of course after successful authentication based on
-the peer's X.509 certificate only) if it declares a client subnet lying totally
-within the brackets defined by the wildcard subnet definition (in our example
-10.4.0.0/24). For each roadwarrior a connection instance tailored to the
-subnet of the particular client will be created,based on the generic
-rightsubnetwithin template.
-
-This strongSwan feature can also be helpful with VPN clients getting a
-dynamically assigned inner IP from a DHCP server located on the NAT router box.
-
-
-4.5 Protocol and Port Selectors
- ---------------------------
-
-strongSwan offer the possibility to restrict the protocol and optionally the
-ports in an IPsec SA using the rightprotoport and leftprotoport parameters.
-
-Some examples:
-
-conn icmp
- right=%any
- rightprotoport=icmp
- left=%defaultroute
- leftid=@moon.strongswan.org
- leftprotoport=icmp
-
-conn http
- right=%any
- rightprotoport=6
- left=%defaultroute
- leftid=@moon.strongswan.org
- leftprotoport=6/80
-
-conn l2tp # with port wildcard for Mac OS X Panther interoperability
- right=%any
- rightprotoport=17/%any
- left=%defaultroute
- leftid=@moon.strongswan.org
- leftprotoport=17/1701
-
-conn dhcp
- right=%any
- rightprotoport=udp/bootpc
- left=%defaultroute
- leftid=@moon.strongswan.org
- leftsubnet=0.0.0.0/0 #allows DHCP discovery broadcast
- leftprotoport=udp/bootps
- rekey=no
- keylife=20s
- rekeymargin=10s
- auto=add
-
-Protocols and ports can be designated either by their numerical values
-or by their acronyms defined in /etc/services.
-
- ipsec status
-
-shows the following connection definitions:
-
-"icmp": 192.168.0.1[@moon.strongswan.org]:1/0...%any:1/0
-"http": 192.168.0.1[@moon.strongswan.org]:6/80...%any:6/0
-"l2tp": 192.168.0.1[@moon.strongswan.org]:17/1701...%any:17/%any
-"dhcp": 0.0.0.0/0===192.168.0.1[@moon.strongswan.org]:17/67...%any:17/68
-
-Based on the protocol and port selectors appropriate eroutes will be set
-up, so that only the specified payload types will pass through the IPsec
-tunnel.
-
-
-4.6 IPsec policies based on wildcards
- ---------------------------------
-
-In large VPN-based remote access networks there is often a requirement that
-access to the various parts of an internal network must be granted selectively,
-e.g. depending on the group membership of the remote access user. strongSwan
-makes this possible by applying wildcard filtering on the VPN user's
-distinguished name (ID_DER_ASN1_DN).
-
-Let's make a practical example:
-
-An organization has a sales department (OU=Sales) and a research group
-(OU=Research). In the company intranet there are separate subnets for Sales
-(10.0.0.0/24) and Research (10.0.1.0/24) but both groups share a common web
-server (10.0.2.100). The VPN clients use Virtual IP addresses that are either
-assigned statically or via DHCP-over-IPsec. The sales and research departments
-use IP addresses from separate DHCP address pools (10.1.0.0/24) and (10.1.1.0/24),
-respectively. An X.509 certificate is issued to each employee, containing in its
-subject distinguished name the country (C=CH), the company (O=ACME),
-the group membership(OU=Sales or OU=Research) and the common name (e.g.
-CN=Bart Simpson).
-
-The IPsec policy defined above can now be enforced with the following three
-IPsec security associations:
-
-conn sales
- right=%any
- rightid="C=CH, O=ACME, OU=Sales, CN=*"
- rightsubnetwithin=10.1.0.0/24 # Sales DHCP range
- leftsubnet=10.0.0.0/24 # Sales subnet
-
-conn research
- right=%any
- rightid="C=CH, O=ACME, OU=Research, CN=*"
- rightsubnetwithin=10.1.1.0/24 # Research DHCP range
- leftsubnet=10.0.1.0/24 # Research subnet
-
-conn web
- right=%any
- rightid="C=CH, O=ACME, OU=*, CN=*"
- rightsubnetwithin=10.1.0.0/23 # Remote access DHCP range
- leftsubnet=10.0.2.100/32 # Web server
- rightprotoport=tcp # TCP protocol only
- leftprotoport=tcp/http # TCP port 80 only
-
-Of course group specific tunneling could be implemented on the
-basis of the Virtual IP range specified by the rightsubnetwithin
-parameter alone, but the wildcard matching mechanism guarantees that
-only authorized user can access the corresponding subnets.
-
-The '*' character is used as a wildcard in relative distinguished names (RDNs).
-In order to match a wildcard template, the ID_DER_ASN1_DN of a peer must contain
-the same number of RDNs (selected from the list in section 4.3) appearing in the
-exact order defined by the template.
-
- "C=CH, O=ACME, OU=Research, OU=Special Effects, CN=Bart Simpson"
-
-matches the templates
-
- "C=CH, O=ACME, OU=Research, OU=*, CN=*"
-
- "C=CH, O=ACME, OU=*, OU=Special Effects, CN=*"
-
- "C=CH, O=ACME, OU=*, OU=*, CN=*"
-
-but not the template
-
- "C=CH, O=ACME, OU=*, CN=*"
-
-which doesn't have the same number of RDNs.
-
-
-4.7 IPsec policies based on CA certificates
- ---------------------------------------
-
-As an alternative to the wildcard based IPsec policies described in section 4.6,
-access to specific client host and subnets can abe controlled on the basis of
-the CA that issued the peer certificate
-
-
-conn sales
- right=%any
- rightca="C=CH, O=ACME, OU=Sales, CN=Sales CA"
- rightsubnetwithin=10.1.0.0/24 # Sales DHCP range
- leftsubnet=10.0.0.0/24 # Sales subnet
-
-conn research
- right=%any
- rightca="C=CH, O=ACME, OU=Research, CN=Research CA"
- rightsubnetwithin=10.1.1.0/24 # Research DHCP range
- leftsubnet=10.0.1.0/24 # Research subnet
-
-conn web
- right=%any
- rightca="C=CH, O=ACME, CN=ACME Root CA"
- rightsubnetwithin=10.1.0.0/23 # Remote access DHCP range
- leftsubnet=10.0.2.100/32 # Web server
- rightprotoport=tcp # TCP protocol only
- leftprotoport=tcp/http # TCP port 80 only
-
-In the example above, the connection "sales" can be used by peers
-presenting certificates issued by the Sales CA, only. In the same way,
-the use of the connection "research" is restricted to owners of certificates
-issued by the Research CA. The connection "web" is open to both "Sales" and
-"Research" peers because the required "ACME Root CA" is the issuer of the
-Research and Sales intermediate CAs. If no rightca parameter is present
-then any valid certificate issued by one of the trusted CAs in
-/etc/ipsec.d/cacerts can be used by the peer.
-
-The leftca parameter usually doesn't have to be set explicitly because
-by default it is set to the issuer field of the certificate loaded via
-leftcert. The statement
-
- rightca=%same
-
-sets the CA requested from the peer to the CA used by the left side itself
-as e.g. in
-
-conn sales
- right=%any
- rightca=%same
- leftcert=mySalesCert.pem
-
-
-4.8 Sending certificate requests
- ----------------------------
-
-The presence of a rightca parameter also causes the CA to be sent as
-part of the certificate request message when strongSwan is the initiator.
-A special case occurs when strongSwan responds to a roadwarrior. If several
-roadwarrior connections based on different CAs are defined then all eligible
-CAs will be listed in Pluto\92s certificate request message.
-
-
-4.9 IPsec policies based on group attributes
- ----------------------------------------
-
-X.509 attribute certificates are the most powerful mechanism for implementing
-IPsec security policies. The rightgroups parameter in a connection definition
-restricts the access to members of the listed groups only. An IPsec peer must
-have a valid attribute certificate issued by a trusted Authorization Authority
-and listing one of the requirede group attributes in order to get admitted.
-
-conn sales
- right=%any
- rightgroups="Sales"
- rightsubnetwithin=10.1.0.0/24 # Sales DHCP range
- leftsubnet=10.0.0.0/24 # Sales subnet
-
-conn research
- right=%any
- rightgroups="Research"
- rightsubnetwithin=10.1.1.0/24 # Research DHCP range
- leftsubnet=10.0.1.0/24 # Research subnet
-
-conn web
- right=%any
- rightgroups="Sales, Research"
- rightsubnetwithin=10.1.0.0/23 # Remote access DHCP range
- leftsubnet=10.0.2.100/32 # Web server
- rightprotoport=tcp # TCP protocol only
- leftprotoport=tcp/http # TCP port 80 only
-
-In the examples above membership of the group "Sales" is required for
-connection sales and membership of "Research" for connection research
-whereas connection web is accessible for both groups.
-
-Currently the attribute certificates of the peers must be loaded statically
-via the /etc/ipsec.d/acerts/ directory. In future releases of strongSwan it
-will be possible to fetch them from an LDAP directory server.
-
-
-5. Configuring certificates and CRLs
- ---------------------------------
-
-
-5.1 Installing the CA certificates
- ------------------------------
-
-X.509 certificates received by strongSwan during the IKE protocol are
-automatically authenticated by going up the trust chain until a self-signed
-root CA certificate is reached. Usually host certificates are directly signed
-by a root CA, but strongSwan also supports multi-level hierarchies with
-intermediate CAs in between. All CA certificates belonging to a trust chain
-must be copied in either binary DER or base64 PEM format into the directory
-
- /etc/ipsec.d/cacerts/
-
-
-5.2 Installing optional certificate revocation lists (CRLs)
- -------------------------------------------------------
-
-By copying a CA certificate into /etc/ipsec.d/cacerts/, automatically all user
-or host certificates issued by this CA are declared valid. Unfortunately
-private keys might get compromised inadvertently or intentionally, personal
-certificates of users leaving a company have to be blocked immediately, etc.
-To this purpose certificate revocation lists (CRLs) have been created. CRLs
-contain the serial numbers of all user or host certificates that have been
-revoked due to various reasons.
-
-After successful verification of the X.509 trust chain, Pluto searches its
-list of CRLs either obtained by loading them from the /etc/ipsec.d/crls/
-directory or fetching them dynamically from a HTTP or LDAP server for the
-presence of a CRL issued by the CA that has signed the certificate.
-
-If the serial number of the certificate is found in the CRL then the public key
-contained in the certificate is declared invalid and the IPSec SA will not be
-established. If no CRL is found or if the deadline defined in the nextUpdate
-field of the CRL has been reached, a warning is issued but the public key will
-nevertheless be accepted. CRLs must be stored either in binary DER or base64 PEM
-format in the crls directory. Section 7.3 will explain in detail how CRLs can
-be created using OpenSSL.
-
-
-5.3 Dynamic update of certificates and CRLs
- ---------------------------------------
-
-Pluto reads certificates and CRLs from their respective files during system
-startup and keeps them in memory in the form of chained lists. X.509
-certificates have a finite life span defined by their validity field. Therefore
-it must be possible to replace CA or OCSP certificates kept in system memory
-without disturbing established ISAKMP SAs. Certificate revocation lists should
-also be updated in the regular intervals indicated by the nextUpdate field in
-the CRL body. The following interactive commands allow the manual replacement
-of the various files:
-
-+---------------------------------------------------------------------------+
-| ipsec rereadsecrets reload file /etc/ipsec.secrets |
-|---------------------------------------------------------------------------|
-| ipsec rereadcacerts reload all files in /etc/ipsec.d/cacerts/ |
-|---------------------------------------------------------------------------|
-| ipsec rereadaacerts reload all files in /etc/ipsec.d/aacerts/ |
-|---------------------------------------------------------------------------|
-| ipsec rereadocspcerts reload all files in /etc/ipsec.d/ocspcerts/ |
-|---------------------------------------------------------------------------|
-| ipsec rereadacerts reload all files in /etc/ipsec.d/acerts/ |
-|---------------------------------------------------------------------------|
-| ipsec rereadcrls reload all files in /etc/ipsec.d/crls/ |
-|---------------------------------------------------------------------------|
-| ipsec rereadall ipsec rereadsecrets |
-| rereadcacerts |
-| rereadaacerts |
-| rereadocspcerts |
-| rereadacerts |
-| rereadcrls |
-|---------------------------------------------------------------------------|
-| ipsec purgeocsp purge the OCSP cache and fetching requests |
-+---------------------------------------------------------------------------+
-
-CRLs can also be automatically fetched from an HTTP or LDAP server by using
-the CRL distribution points contained in X.509 certificates. The command
-
- ipsec listcrls
-
-shows any pending fetch requests:
-
- Oct 31 00:29:53 2002, trials: 2
- issuer: 'C=CH, O=Linux strongSwan, CN=strongSwan Root CA'
- distPts: 'http://crl.strongswan.org/strongswan.crl'
- 'ldap://ldap.strongswan.org/o=Linux strongSwan, c=CH
- ?certificateRevocationList?base
- ?(objectClass=certificationAuthority)'
-
-In the example above, an http and an ldap URL were extracted from a received
-end certificate. An independent thread then tries to fetch a CRL from the
-designated distribution points. The same thread also periodically checks
-if any loaded CRLs are about to expire. The check interval can be defined in
-the "config setup" section of the ipsec.conf file:
-
- config setup
- crlcheckinterval=600
-
-In our example the thread wakes up every 600 seconds or 10 minutes in order
-to check the validity of the CRLs or to retry any pending fetch requests:
-
- List of X.509 CRLs:
-
- Dec 19 09:35:31 2002, revoked certs: 40
- issuer: 'C=CH, O=Linux strongSwan, CN=strongSwan Root CA'
- distPts: 'http://crl.strongswan.org/strongswan.crl'
- updates: this Dec 19 09:35:00 2002
- next Dec 19 10:35:00 2002 warning (expires in 19 minutes)
-
- List of fetch requests:
-
- Dec 19 10:15:31 2002, trials: 1
- issuer: 'C=CH, O=Linux strongSwan, CN=strongSwan Root CA'
- distPts: 'http://crl.strongwan.org/strongswan.crl'
-
-The first trial to update a CRL is started 2*crlcheckinterval before the
-nextUpdate time, i.e. when less than 20 minutes are left in our practical
-example. When crlcheckinterval is set to 0 (this is also the default value
-when the parameter is not set in ipsec.conf) then the CRL checking and updating
-thread is not started and dynamic CRL fetching is disabled.
-
-
-5.4 Local caching of CRLs
- ---------------------
-
-The the ipsec.conf option
-
- config setup
- cachecrls=yes
-
-activates the local caching of CRLs that were dynamically fetched from an
-HTTP or LDAP server. Cached copies are stored in /etc/ipsec.d/crls under a
-unique filename formed from the issuer's SubjectKeyIdentifier and the suffix .crl.
-
-With the cached copy the CRL is immediately available after pluto's startup.
-When the local copy is about to expire it is automatically replaced with an
-updated CRL fetched from one of the defined CRL distribution points.
-
-
-5.5 Online Certificate Status Protocol (OCSP)
- -----------------------------------------
-
-The Online Certificate Status Protocol is defined by RFC 2560. It can be
-used to query an OCSP server about the current status of an X.509 certificate
-and is often used as a more dynamic alternative to a static Certificate
-Revocation List (CRL). Both the OCSP request sent by the client and the OCSP
-response messages returned by the server are transported via a standard
-TCP/HTTP connection. Therefore cURL support must be enabled in pluto/Makefile:
-
- # Uncomment this line to enable OCSP fetching using HTTP
- LIBCURL=1
-
-In the simplest OCSP setup, a default URI under which the OCSP server for a
-given CA can be accessed is defined in ipsec.conf:
-
- config setup
- crlcheckinterval=600
-
- ca strongswan
- cacert=strongswanCert.pem
- ocspuri=http://ocsp.strongswan.org:8880
- auto=add
-
-The HTTP port can be freely chosen. In our example we have assumed TCP port 8880.
-The crlcheckinterval must be set to a value different from zero. Otherwise the
-OCSP fetching thread will not be started.
-
-The well-known openssl-0.9.7 package from http://www.openssl.org implements
-an OCSP server that can be used in conjunction with an openssl-based Public
-Key Infrastructure. The OCSP client integrated into Pluto does not contain
-any OpenSSL code though, but is based on the existing ASN.1 functionality of
-strongSwan.
-
-The OpenSSL-based OCSP server is started with the following command:
-
- openssl ocsp -index index.txt -CA strongswanCert.pem -port 8880 \
- -rkey ocspKey.pem -rsigner ocspCert.pem \
- -resp_no_certs -nmin 60 -text
-
-The command consists of the parameters
-
- -index index.txt is a copy of the OpenSSL index file containing the list of
- all issued certificates. The certificate status in indext.txt
- is designated either by V for valid or R for revoked. If
- a new certificate is added or if a certificate is revoked
- using the openssl ca command, the OCSP server must be restarted
- in order for the changes in index.txt to take effect.
-
- -CA the CA certificate
-
- -port the HTTP port the OCSP server is listening on.
-
--rkey the private key used to sign the OCSP response. The use of the
- sensitive CA private key is not recommended since this could
- jeopardize the security of your production PKI if the OCSP
- server is hacked. It is much better to generate a special
- RSA private key just for OCSP signing use instead.
-
--rsigner the certificate of the OCSP server containing a public key which
- matches the private key defined by -rkey and which can be used by
- the client to check the trustworthiness of the signed OCSP response.
-
--resp_no_certs With this option the OCSP signer certificate defined by
- -rsigner is not included in the OCSP response.
-
--nmin the validity interval of an OCSP response given in minutes.
- 2*crlcheckinterval before the expiration of the OCSP responses,
- a new query will by pro-actively started by the Pluto fetching thread.
-
- If nmin is missing or set to zero then the default validity interval
- compiled into Pluto will be 2 minutes, leading to a quasi one-time
- use of the OCSP status response which will not be periodically
- refreshed by the fetching thread. In conjunction with the parameter
- setting "strictcrlpolicy=yes" a real-time certificate status query
- can be implemented in this way.
-
--text This option activates a verbose logging output, showing the contents
- of both the received OCSP request and sent OCSP response.
-
-How does Pluto get hold of the OCSP signer certificate? There are two
-possibilities:
-
-Either you put the OCSP certificate into the default directory
-
- /etc/ipsec.d/ocspcerts
-
-or alternatively Pluto can receive it as part of the OCSP response from the
-remote OCSP server. In the latter case, how can Pluto make sure that
-the server has indeed been authorized by the CA to deal out certificate status
-information? In order to ascertain the OCSP signer capability, an extended
-key usage attribute can be included in the OCSP server certificate. Just
-insert the parameter
-
- extendedKeyUsage=OCSPSigner
-
-in the [ usr_cert ] section of your openssl.cnf configuration file before
-the CA signs the OCSP server certificate.
-
-For a given CA the corresponding ca section in ipsec.conf (see section 7) allows
-to define the URI of a single OCSP server. As an alternative an OCSP URI can be
-embedded into each host and user certificate by putting the line
-
- authorityInfoAccess = OCSP;URI:http://ocsp.strongswan.org:8880
-
-into the [ usr_cert ] section of your openssl.cnf configuration file.
-If an OCSP authorityInfoAccess extension is present in a certificate then this
-record overrides the default URI defined by the ca section.
-
-
-5.6 CRL Policy
- ----------
-
-By default Pluto is quite tolerant concerning the handling of CRLs. It is not
-mandatory for a CRL to be present in /etc/ipsec.d/crls and if the expiration
-date defined by the nextUpdate field of a CRL has been reached just a warning
-is issued but a peer certificate will always be accepted if it has not been
-revoked.
-
-If you want to enforce a stricter CRL policy then you can do this by setting
-the "strictcrlpolicy" option. This is done in the "config setup" section
-of the ipsec.conf file:
-
- config setup
- strictcrlpolicy=yes
- ...
-
-A certificate received from a peer will not be accepted if no corresponding
-CRL or OCSP response is available. And if an ISAKMP SA re-negotiation takes
-place after the nextUpdate deadline has been reached, the peer certificate
-will be declared invalid and the cached RSA public key will be deleted, causing
-the connection in question to fail. Therefore if you are going to use the
-"strictcrlpolicy=yes" option, make sure that the CRLs will always be updated
-in time. Otherwise a total standstill would ensue.
-
-As mentioned earlier the default setting is "strictcrlpolicy=no"
-
-
-5.7 Configuring the peer side using locally stored certificates
- -----------------------------------------------------------
-
-If you don't want to use trust chains based on CA certificates as proposed in
-section 4.3 you can alternatively import trusted peer certificates directly
-into Pluto. Thus you do not have to rely on the certificate to be transmitted
-by the peer as part of the IKE protocol.
-
-With the conn %default section defined in section 4.1 and the use of the
-rightcert keyword for the peer side, the connection definitions in section 4.3
-can alternatively be written as
-
- conn sun
- right=%any
- rightid=@sun.strongswan.org
- rightcert=sunCert.cer
-
- conn carol
- right=192.168.0.100
- rightcert=carolCert.der
-
-If the peer certificates are loaded locally then there is no sense in sending
-any certificates to the other end via the IKE Main Mode protocol. Especially
-if self-signed certificates are used which wouldn't be accepted any way by
-the other side. In these cases it is recommended to add
-
- leftsendcert=never
-
-to the connection definition[s] in order to avoid the sending of the host's
-own certificate. The default value is
-
- leftsendcert=always.
-
-If a peer certificate contains a subjectAltName extension, then an alternative
-rightid type can be used, as the example "conn sun" shows. If no rightid
-entry is present then the subject distinguished name contained in the
-certificate is taken as the ID.
-
-Using the same rules concerning pathnames that apply to strongSwan's own
-certificates, the following two definitions are also valid for trusted peer
-certificates:
-
- rightcert=peercerts/carolCert.der
-
-or
-
- rightcert=/usr/ssl/certs/carolCert.der
-
-
-6. Installing the private key - ipsec.secrets
- ------------------------------------------
-
-6.1 Loading private key files in PKCS#1 format
- ------------------------------------------
-
-Besides strongSwan's raw private key format strongSwan has been enabled to
-load RSA private keys in the PKCS#1 file format. The key files can be
-optionally secured with a passphrase.
-
-RSA private key files are declared in /etc/ipsec.secrets using the syntax
-
- : RSA <my keyfile> "<optional passphrase>"
-
-The key file can be either in base64 PEM-format or binary DER-format. The
-actual coding is detected "automagically" by Pluto. The example
-
- : RSA moonKey.pem
-
-uses a relative pathname. In this case Pluto will look for the key file
-in the directory
-
- /etc/ipsec.d/private
-
-As an alternative an absolute pathname can be given as in
-
- : RSA /usr/ssl/private/moonKey.pem
-
-In both cases make sure that the key files are root readable only.
-
-Often a private key must be transported from the Certification Authority
-where it was generated to the target security gateway where it is going
-to be used. In order to protect the key it can be encrypted with 3DES
-using a symmetric transport key derived from a cryptographically strong
-passphrase.
-
- openssl genrsa -des3 -out moonKey.pem 1024
-
-Because of the weak security, key files protected by single DES will not
-be accepted by Pluto!!!
-
-Once on the security gateway the private key can either be permanently
-unlocked so that it can be used by Pluto without having to know a
-passphrase
-
- openssl rsa -in moonKey.pem -out moonKey.pem
-
-or as an option the key file can remain secured. In this case the passphrase
-unlocking the private key must be added after the pathname in
-/etc/ipsec.secrets
-
- : RSA moonKey.pem "This is my passphrase"
-
-Some CAs distribute private keys embedded in a PKCS#12 file. Since Pluto
-is not able yet to read this format directly, the private key part must
-first be extracted using the command
-
- openssl pkcs12 -nocerts -in moonCert.p12 -out moonKey.pem
-
-if the key file moonKey.pem is to be secured again by a passphrase, or
-
- openssl pkcs12 -nocerts -nodes -in moonCert.p12 -out moonKey.pem
-
-if the private key is to be stored unlocked.
-
-
-6.2 Entering passphrases interactively
- ----------------------------------
-
-On a VPN gateway you would want to put the passphrase protecting the private
-key file right into /etc/ipsec.secrets as described in the previous paragraph,
-so that the gateway can be booted in unattended mode. The risk of keeping
-unencrypted secrets on a server can be minimized by putting the box into a
-locked room. As long as no one can get root access on the machine the private
-keys are safe.
-
-On a mobile laptop computer the situation is quite different. The computer can
-be stolen or the user is leaving it unattended so that unauthorized persons
-can get access to it. In theses cases it would be preferable not to keep any
-passphrases openly in /etc/ipsec.secrets but to prompt for them interactively
-instead. This is easily done by defining
-
- : RSA moonKey.pem %prompt
-
-Since strongSwan is usually started during the boot process, usually no
-interactive console windows is available which can be used by Pluto to
-prompt for the passphrase. This must be initiated by the user by typing
-
- ipsec secrets
-
-which actually is an alias for the existing command
-
- ipsec rereadsecrets
-
-and which causes the prompt
-
- need passphrase for '/etc/ipsec.d/private/moonKey.pem'
- Enter:
-
-to appear. If the passphrase was correct and the private key file could be
-successfully decrypted then
-
- valid passphrase
-
-results. Otherwise the prompt
-
- invalid passphrase, please try again
- Enter:
-
-will give you another try. Entering a carriage return will abort the
-the passphrase prompting.
-
-
-6.3 Multiple private keys
- ---------------------
-
-strongSwan supports multiple private keys. Since the connections defined
-in ipsec.conf can find the correct private key based on the public key
-contained in the certificate assigned by leftcert, default private key
-definitions without specific IDs can be used
-
- : RSA myKey1.pem "<optional passphrase1>"
-
- : RSA myKey2.pem "<optional passphrase2>"
-
-
-7. Configuring CA properties - ipsec.conf
- --------------------------------------
-
-Besides the definition of IPsec connections the ipsec.conf file can also
-be used to configure a few properties of the certification authorities
-needed to establish the X.509 trust chains. The following example shows
-the parameters that are currently available:
-
- ca strongswan
- cacert=strongswanCert.pem
- ocspuri=http://ocsp.strongswan.org:8880
- crluri=http://crl.strongswan.org/strongswan.crl'
- crluri2="ldap:///O=Linux strongSwan, C=CH?certificateRevocationList"
- ldaphost=ldap.strongswan.org
- auto=add
-
-In a similar way as conn sections are used for connection definitions, an
-arbitrary number of optional ca sections define the basic properties of CAs.
-
-Each ca section is named with a unique label
-
- ca strongswan
-
-The only mandatory parameter is
-
- cacert=strongswanCert.pem
-
-which points to the CA certificate which usually resides in the default
-directory /etc/ipsec.d/cacerts/ but could also be retrieved via an absolute
-path name. If the CA certificate is stored on a smartcard then the
-notation
-
- cacert=%smartcard#<n>
-
-or alternatively
-
- cacert=%smartcard<optional slot nr>:<key id>
-
-can be used. The selection of smartcard slots is described in more detail
-in section 8.1.
-
-From the certificate the CA's distinguished name and the serial number
-is extracted. If an optional subjectKeyAuthentifier is present then it can
-be used to uniquely identify consecutive generations of CA certificates
-carrying the same distinguished name.
-
-The OCSP URI
-
- ocspuri=http://ocsp.strongswan.org:8880
-
-allows to define an individual OCSP server per CA. Also up to two additional
-CRL distribution points (CDPs) can be defined
-
- crluri=http://crl.strongswan.org/strongswan.crl'
- crluri2="ldap:///O=Linux strongSwan, C=CH?certificateRevocationList"
-
-which are added to any CDPs already present in the received certificates
-themselves. The last parameter
-
- ldaphost=ldap.strongswan.org
-
-can be used to fill in the actual server name in LDAP CDPs where the host is missing
-as e.g. in the crluri2 above. In future releases this ldaphost parameter might be used
-to retrieve user, host and attribute certificates.
-
-
-With the auto=add statement the ca definition is automatically loaded into Pluto during
-system startup. Setting auto=ignore will ignore the ca section. Additional ca definitions
-can be loaded from ipsec.conf during runtime with the command
-
- ipsec auto --type ca --add strongswan-sales
-
-and
-
- ipsec auto --type ca --delete strongswan-sales
-
-deletes the labeled ca entry. And finally the command
-
- ipsec auto --type ca --replace strongswan
-
-first deletes the old definition in Pluto's memory and then loads the updated version
-from ipsec.conf. Any parameters which appear in several ca definitions can be put in
-a common ca %default section
-
- ca %default
- ldaphost=ldap.strongswan.org
-
-
-8. Smartcard support
- -----------------
-
-8.1 Configuring a smartcard-based connection
- ----------------------------------------
-
-Defining a smartcard-based connection in ipsec.conf is easy:
-
- conn sun
- right=192.168.0.2
- rightid=@sun.strongswan.org
- left=%defaultroute
- leftcert=%smartcard
- auto=add
-
-In most cases there is a single smartcard reader or cryptotoken and only one
-RSA private key safely stored on the crypto device. Thus usually the entry
-
- leftcert=%smartcard
-
-which stands for the full notation
-
- leftcert=%smartcard#1
-
-is sufficient where the first certificate/private key object enumerated by
-the PKCS#11 module is used. If several certificate/private key objects are
-present then the nth object can be selected using
-
- leftcert=%smartcard#<n>
-
-The command
-
- ipsec listcards
-
-gives an overview over all certificate objects made available by the PKCS#11
-module.CA certificates are automatically available as trust anchors.
-
-As an alternative the certificate ID and/or the slot number defined by
-the PKCS#11 standard can be specified using the notation
-
- leftcert=%smartcard<optional slot nr>:<key id in hex format>
-
-Thus
-
- leftcert=%smartcard:50
-
-will look in all available slots for ID 0x50 starting with the first slot
-(usually slot 0) whereas
-
- leftcert=%smartcard4:50
-
-will directly check slot 4 (which is usually the first slot on the second
-reader/token when using the OpenSC library) for a key with ID 0x50.
-
-
-8.2 Entering the PIN code
- ---------------------
-
-Since the smartcard signing operation needed to sign the hash with the
-RSA private key during IKE Main Mode is protected by a PIN code,
-the secret PIN must be made available to Pluto.
-
-For gateways that must be able to start IPsec tunnels automatically in
-unattended mode after a reboot, the secret PIN can be stored statically
-in ipsec.secrets
-
- : PIN %smartcard "12345678"
-
-or with the general notation
-
- : PIN %smartcard#<n> "<PIN code>"
-
-or alternatively
-
- : PIN %smartcard<optional slot nr>:<key id> "<PIN code>"
-
-On personal notebooks that could get stolen, you wouldn't want to store
-your PIN in ipsec.secrets. Thus the alternative form
-
- : PIN %smartcard %prompt
-
-will prompt you for the PIN when you start up the first IPsec connection
-using the command
-
- ipsec up sun
-
-The auto command calls the whack function which in turn communicates with
-Pluto over a socket. Since the whack function call is executed from a command
-window, Pluto can prompt you for the PIN over this socket connection.
-Unfortunately roadwarrior connections which just wait passively for peers
-cannot be initiated via the command window:
-
- conn rw
- right=%any
- left=%defaultroute
- leftcert=%smartcard4:50
- auto=add
-
-But if there is a corresponding entry
-
- : PIN %smartcard4:50 %prompt
-
-in ipsec.secrets, then the standard command
-
- ipsec rereadsecrets
-
-or the alias
-
- ipsec secrets
-
-can be used to enter the PIN code for this connection interactively.
-
-The command
-
- ipsec listcards
-
-can be executed at any time to check the current status of the PIN code[s].
-
-
-8.3 PIN-pad equipped smartcard readers
- ----------------------------------
-
-Smartcard readers with an integrated PIN-pad offer an increased security
-level because the PIN entry cannot be sniffed on the host computer e.g.
-by a surrepticiously installed key logger. In order to tell pluto not to
-prompt for the PIN on the host itself, the entry
-
- : PIN %smartcard:50 %pinpad
-
-can be used in ipsec.secrets. Because the key pad does not cache the PIN in
-the smartcard reader, it must be entered for every PKCS #11 session login.
-By default pluto does a session logout after every RSA signature. In order
-to avoid the repeated entry of the PIN code during the periodic IKE main
-mode rekeyings, the following parameter can be set in the config setup
-section of ipsec.conf:
-
- config setup
- pkcs11keepstate=yes
-
-The default setting is pkcs11keepstate=no.
-
-
-8.4 Configuring a smartcard with pkcsc15-init
- -----------------------------------------
-
-strongSwan's smartcard solution is based on the PKCS#15 "Cryptographic Token
-Information Format Standard" fully supported by OpenSC library functions.
-Using the command
-
- pkcs15-init --erase-card --create-pkcs15
-
-a fresh PKCS#15 file structure is created on a smartcard or cryptotoken.
-With the next command
-
- pkcs15-init --auth-id 1 --store-pin --pin "12345678" --puk "87654321"
- --label "my PIN"
-
-a secret PIN code with auth-id 1 is stored in an unretrievable location on
-the smart card. The PIN will protect the RSA signing operation. If the PIN
-is entered incorrectly more than three times the smartcard will be locked
-and the PUK code can be used to unlock the card again.
-
-Next the RSA private key is transferred to the smartcard
-
- pkcs15-init --auth-id 1 --store-private-key myKey.pem [--id 45]
-
-By default the PKCS#15 smartcard record will be assigned the id 45.
-Using the --id option multiple key records can be stored on a smartcard.
-
-At last we load the matching X.509 certificate onto the smartcard
-
- pkcs15-init --auth-id 1 --store-certificate myCert.pem [--id 45]
-
-The pkcs15-tool can now be used to verify the contents of the smartcard.
-
- pkcs15-tool --list-pins --list-keys --list-certificates
-
-If everything is ok then you are ready to use the generated PKCS#15
-structure with strongSwan.
-
-8.5 PKCS#11 proxy functions
- -----------------------
-
- With the setting pkcs11keepstate=yes some PKCS#11 implementations
- (e.g. OpenSC) will lock the access to the smartcard as soon as pluto has
- opened a session and will thus prevent other application from sharing the
- smartcard resource. In order to solve this locking problem, strongSwan
- offers a PKCS#11 proxy service making use of the whack socket communication
- channel. The setting
-
- config setup
- pkcs11proxy=yes
-
-will enable the proxy mode that is disabled by default.
-
-Currently two smartcard operations are supported: RSA encryption and
-RSA decryption. The notation is as follows:
-
- ipsec scdecrypt <encrypted data>
- [--inbase 16|hex|64|base64|256|text|ascii]
- [--outbase 16|hex|64|base64|256|text|ascii]
- [--keyid <id>]
-
-The default settings for inbase and outbase is hexadecimal.
-Thus the simplest call has the form
-
- ipsec scdecrypt bb952b71920094ce0696ef9b8b26...12e6
-
-and the returned result might be a decrypted 128 bit AES key
-
- 000 8836362e030e6707c32ffaa0bdad5540
-
-The leading three characters represent the return code of the whack channel
-with 000 signifying that no error has occured. Here is another example showing
-the use of the inbase and outbase attributes
-
- ipsec scdecrypt m/ewDnTs0k...woE= --inbase base64 --outbase text
-
-where the result has the form
-
- 000 This is a secret
-
-By default the first RSA private key found by the PKCS#11 enumeration is
-used. If a different key should be selected then the notation introduced
-in sections 8.1 and 8.2 can be used:
-
- --keyid %smartcard:50
- --keyid %smartcard4:50
- --keyid %smartcard#3
-
-with --keyid %smartcard#1 being the default. If supported by the smartcard
-and PKCS#11 library RSA encryption can be used with the notation
-
- ipsec scencrypt <plaintext data>
- [--inbase 16|hex|64|base64|256|text|ascii]
- [--outbase 16|hex|64|base64|256|text|ascii]
- [--keyid <id>]
-
-with the example
-
- ipsec scencrypt "This is a secret" --inbase ascii --outbase 64
-
-returning the expected output
-
- 000 m/ewDnTs0k...woE=
-
-
-9. Configuring the clients
- -----------------------
-
-9.1 strongSwan
- ----------
-
-A strongSwan to strongSwan connection is symmetrical. Any of the four defined
-ID types can be used, even different types on either end of the connection,
-although this wouldn't make much sense.
-
-+--------------------------------------------------------------+
-| Connection Definition ID type subjectAltName |
-|--------------------------------------------------------------|
-| rightid (strongSwan) DER_ASN1_DN - |
-| FQDN DNS: |
-| USER_FQDN email: |
-| IPV4_ADDR IP: |
-|--------------------------------------------------------------|
-| leftid (strongSwan) DER_ASN1_DN - |
-| FQDN DNS: |
-| USER_FQDN email: |
-| IPV4_ADDR IP: |
-+--------------------------------------------------------------+
-
-
-9.2 PGPnet
- ------
-
-Use the file peerCert.p12 to import PGPnet's X.509 certificate, the CA
-certificate, plus the encrypted private key in binary PKCS#12 format into the
-PGPkey tool. You will be prompted for the passphrase securing the private key.
-
-Use the file myCert.pem to import the X.509 certificate of the strongSwan
-security gateway into the PGPkey tool. The PGPkeyTool does not accept X.509
-certificates in binary DER format, so it must be imported in base64 format:
-
- -----BEGIN CERTIFICATE-----
- M...
-
- ...
- -----END CERTIFICATE-----
-
-Make sure that there is no human-readable listing of the X.509 certificate in
-front of the line
-
- -----BEGIN CERTIFICATE-----
-
-otherwise PGPnet will refuse to load the *.PEM file. Any surplus lines can
-either be deleted by loading the certificate into a text editor or you can
-apply the command
-
- openssl x509 -in myCert.pem -out myCert.pem
-
-to achieve the same effect.
-
-With authentication based on X.509 certificates, PGPnet always sends the ID
-type DER_ASN1_DN, therefore rightid in the connection definition of the
-strongSwan security gateway must be an ASN.1 distinguished name.
-
-In the receiving direction PGPnet accepts all four ID types from strongSwan.
-
-+--------------------------------------------------------------+
-| Connection Definition ID type subjectAltName |
-|--------------------------------------------------------------|
-| rightid (PGPnet) DER_ASN1_DN - |
-|--------------------------------------------------------------|
-| leftid (strongSwan) DER_ASN1_DN - |
-| FQDN DNS: |
-| USER_FQDN email: |
-| IPV4_ADDR IP: |
-+--------------------------------------------------------------+
-
-
-9.3 SafeNet/Soft-PK/Soft-Remote
- ---------------------------
-
-SafeNet/Soft-PK and SafeNet/Soft-Remote can be configured to send their
-identity either as DER_ASN1_DN, IPV4_ADDR, FQDN, or USER_FQDN.
-In the receiving direction SafeNet/Soft-PK and SafeNet/Soft-Remote
-accept all four ID types coming from strongSwan.
-
-+--------------------------------------------------------------+
-| Connection Definition ID type subjectAltName |
-|--------------------------------------------------------------|
-| rightid (SafeNet/Soft-PK) DER_ASN1_DN - |
-| FQDN DNS: |
-| USER_FQDN email: |
-| IPV4_ADDR IP: |
-|--------------------------------------------------------------|
-| leftid (strongSwan) DER_ASN1_DN - |
-| FQDN DNS: |
-| USER_FQDN email: |
-| IPV4_ADDR IP: |
-+--------------------------------------------------------------+
-
-
-9.4 SSH Sentinel
- ------------
-
-SSH Sentinel sends its identity as DER_ASN1_DN if the subjectAltName field of
-its certificate is empty. If a subjectAltName field is present, then the
-corresponding type IPV4_ADDR, FQDN, or USER_FQDN is automatically chosen.
-With several subjectAltName entries, the precedence of the different ID types
-is not quite clear. In the receiving direction SSH Sentinel accepts all four
-ID types from strongSwan.
-
-+--------------------------------------------------------------+
-| Connection Definition ID type subjectAltName |
-|--------------------------------------------------------------|
-| rightid (SSH Sentinel) DER_ASN1_DN - |
-| FQDN DNS: |
-| USER_FQDN email: |
-| IPV4_ADDR IP: |
-|--------------------------------------------------------------|
-| leftid (strongSwan) DER_ASN1_DN - |
-| FQDN DNS: |
-| USER_FQDN email: |
-| IPV4_ADDR IP: |
-+--------------------------------------------------------------+
-
-
-9.5 Windows 2000/XP
- ---------------
-
-Windows 2000 and Windows XP always send the ID type DER_ASN1_DN,
-therefore rightid in the connection definition of the strongSwan
-security gateway must be an ASN.1 distinguished name.In the
-receiving direction Windows 2000/XP accepts all four ID types
-from strongSwan.
-
-+--------------------------------------------------------------+
-| Connection Definition ID type subjectAltName |
-|--------------------------------------------------------------|
-| rightid (Windows 2000/XP) DER_ASN1_DN - |
-|--------------------------------------------------------------|
-| leftid (strongSwan) DER_ASN1_D - |
-| FQDN DNS: |
-| USER_FQDN email: |
-| IPV4_ADDR IP: |
-+--------------------------------------------------------------+
-
-
-10. Monitoring functions
- --------------------
-
-strongSwan offers the following monitoring functions:
-
-
- ipsec listalgs
-
-lists all IKE and ESP cryptographic algorithms that are currently
-registered with strongSwan.
-
-The a listing has the following form:
-
- List of registered IKE Encryption Algorithms:
-
- #3 OAKLEY_BLOWFISH_CBC, blocksize: 64, keylen: 128-128-256
- #5 OAKLEY_3DES_CBC, blocksize: 64, keylen: 192-192-192
- #7 OAKLEY_AES_CBC, blocksize: 128, keylen: 128-128-256
- #65004 OAKLEY_SERPENT_CBC, blocksize: 128, keylen: 128-128-256
- #65005 OAKLEY_TWOFISH_CBC, blocksize: 128, keylen: 128-128-256
- #65289 OAKLEY_TWOFISH_CBC_SSH, blocksize: 128, keylen: 128-128-256
-
- List of registered IKE Hash Algorithms:
-
- #1 OAKLEY_MD5, hashsize: 128
- #2 OAKLEY_SHA, hashsize: 160
- #4 OAKLEY_SHA2_256, hashsize: 256
- #6 OAKLEY_SHA2_512, hashsize: 512
-
- List of registered IKE DH Groups:
-
- #2 OAKLEY_GROUP_MODP1024, groupsize: 1024
- #5 OAKLEY_GROUP_MODP1536, groupsize: 1536
- #14 OAKLEY_GROUP_MODP2048, groupsize: 2048
- #15 OAKLEY_GROUP_MODP3072, groupsize: 3072
- #16 OAKLEY_GROUP_MODP4096, groupsize: 4096
- #17 OAKLEY_GROUP_MODP6144, groupsize: 6144
- #18 OAKLEY_GROUP_MODP8192, groupsize: 8192
-
- List of registered ESP Encryption Algorithms:
-
- #3 ESP_3DES, blocksize: 64, keylen: 168-168
- #7 ESP_BLOWFISH, blocksize: 64, keylen: 96-128
- #12 ESP_AES, blocksize: 128, keylen: 128-256
- #252 ESP_SERPENT, blocksize: 128, keylen: 128-256
- #253 ESP_TWOFISH, blocksize: 128, keylen: 128-256
-
- List of registered ESP Authentication Algorithms:
-
- #1 AUTH_ALGORITHM_HMAC_MD5, keylen: 128-128
- #2 AUTH_ALGORITHM_HMAC_SHA1, keylen: 160-160
- #5 AUTH_ALGORITHM_HMAC_SHA2_256, keylen: 256-256
- #7 AUTH_ALGORITHM_HMAC_SHA2_512, keylen: 512-512
-
-
-The command
-
- ipsec listpubkeys [--utc]
-
-lists all public keys currently installed in the chained list of public
-keys. These keys were statically loaded from ipsec.conf or aquired either
-from received certificates or retrieved from secure DNS servers using
-opportunistic mode.
-
-The public key listing has the following form:
-
- Feb 11 14:40:18 2005, 2048 RSA Key AwEAAa+uL,
- until Sep 09 13:17:25 2009 ok
- ID_FQDN '@moon.strongswan.org'
- issuer: 'C=CH, O=Linux strongSwan, CN=strongSwan Root CA'
- serial: '03'
- Feb 11 14:40:18 2005, 2048 RSA Key AwEAAa+uL,
- until Sep 09 13:17:25 2009 ok
- ID_DER_ASN1_DN 'C=CH, O=Linux strongSwan, CN=moon.strongswan.org'
- issuer: 'C=CH, O=Linux strongSwan, CN=strongSwan Root CA'
- serial: '03'
- Feb 11 13:36:53 2005, 2048 RSA Key AwEAAbgbh,
- until Dec 31 22:43:18 2009 ok
- ID_USER_FQDN 'carol@strongswan.org'
- issuer: 'C=CH, O=Linux strongSwan, CN=strongSwan Root CA'
- serial: '0a'
-
-It consists of
-
- - the date the public key was installed either in local time or UTC (--utc)
- - the modulus size of the RSA key in bits
- - a keyID consisting of 9 base64 symbols representing the public exponent
- and the most significant bits of the modulus
- - the expiration date of the public key (extracted from the certificate)
- - the type and value of the ID associated with the public key.
- - the issuer of the certificate the public key was extracted from.
- - the serial number of the certificate the public key was extracted from.
-
-A public key can be associated with several IDs, e.g. using subjectAltNames
-in certificates and an ID can possess several public keys, e.g. retrieved
-from a secure DNS server.
-
-
-The command
-
- ipsec listcerts [--utc]
-
-lists all local certificates, both strongSwan's own and those of
-trusted peer loaded via leftcert and rightcert, respectively.
-
-The output has the form
-
- Feb 11 13:36:47 2005, count: 4
- subject: 'C=CH, O=Linux strongSwan, CN=moon.strongswan.org'
- issuer: 'C=CH, O=Linux strongSwan, CN=strongSwan Root CA'
- serial: 03
- pubkey: 2048 RSA Key AwEAAa+uL, has private key
- validity: not before Sep 10 13:17:25 2004 ok
- not after Sep 09 13:17:25 2009 ok
- subjkey: e5:e4:10:87:6c:2a:c4:be:ad:85:49:42:a6:de:76:58:30:3a:9f:c1
- authkey: 5d:a7:dd:70:06:51:32:7e:e7:b6:6d:b3:b5:e5:e0:60:ea:2e:4d:ef
- aserial: 00
-
-and shows
-
- - the date the certificate was installed either in local time or UTC (--utc)
- - the count shows how many connections refer to this certificate
- - the subject of the certificate
- - the issuer of the certificate
- - the serial number of the certificate
- - the size and keyid of the RSA public key contained in the certificate.
- the label "has private key" indicates that a matching RSA private key
- has been found, defined or loaded in ipsec.secrets.
- - the label "on smartcard" indicates that the certificate was loaded from
- a smartcard or cryptotoken and that most probably a matching RSA private
- key also resides on-card.
- - the validity of the CA certificate expressed either in local time or
- UTC (--utc). The validity is checked automatically resulting either
- in an "ok" message or a "fatal" error message.
- - the optional subjectKeyIdentifier extension which is a 20 byte SHA-1 hash
- over the certificate's public key.
- - the optional authorityKeyIdentifier extension which is a 20 byte SHA-1 hash
- over the public key of the issuer who signed the certificate.
- - the serial number of the issuer's certificate.
-
-
-The command
-
- ipsec listcacerts [--utc]
-
-lists all CA certificates that have been either been loaded from the directory
-/etc/ipsec.d/cacerts/ or received via the IKE protocol. The output has the form
-
- Feb 11 13:36:52 2005, count: 1
- subject: 'C=CH, O=Linux strongSwan, CN=strongSwan Root CA'
- issuer: 'C=CH, O=Linux strongSwan, CN=strongSwan Root CA'
- serial: 00
- pubkey: 2048 RSA Key AwEAAb/yX
- validity: not before Sep 10 13:01:45 2004 ok
- not after Sep 08 13:01:45 2014 ok
- subjkey: 5d:a7:dd:70:06:51:32:7e:e7:b6:6d:b3:b5:e5:e0:60:ea:2e:4d:ef
- authkey: 5d:a7:dd:70:06:51:32:7e:e7:b6:6d:b3:b5:e5:e0:60:ea:2e:4d:ef
- aserial: 00
-
-and shows
-
- - the date the CA certificate was installed either in local time or UTC (--utc)
- - the count is always set to 1
- - the subject of the CA certificate
- - the issuer of the CA certificate
- - the serial number of the CA certificate
- - the size and keyid of the RSA public key contained in the certificate.
- - the validity of the CA certificate expressed either in local time or
- UTC (--utc). The validity is checked automatically resulting either
- in an "ok" message or a "fatal" error message.
- - the optional subjectKeyIdentifier extension which is a 20 byte SHA-1 hash
- over the CA certificate's public key.
- - the optional authorityKeyIdentifier extension which is a 20 byte SHA-1 hash
- over the public key of the issuer who signed the CA certificate.
- For Root CA certificates the authorityKeyIdentifier and subjectKeyIdentifier
- fields must be equal.
- - the serial number of the issuer's certificate.
-
-
-The command
-
- ipsec listaacerts [--utc]
-
-lists all Authorization Authority certificates that have been loaded from
-the directory /etc/ipsec.d/aacerts/.
-The output has the form
-
- Dec 20 13:29:55 2004, count: 1
- subject: 'C=CH, O=strongSec GmbH, CN=strongSec Authorization Authority'
- issuer: 'C=CH, O=strongSec GmbH, CN=strongSec Root CA'
- serial: 0f
- pubkey: 2048 RSA Key AwEAAfazH
- validity: not before Aug 24 13:41:56 2003 ok
- not after Aug 23 13:41:56 2005 ok
- subjkey: 56:89:b9:28:c9:1b:a0:00:7f:50:9d:ec:28:75:23:c1:1e:d1:dd:90
- authkey: af:80:d5:c6:02:1c:96:78:b3:85:a5:65:a2:23:fd:ad:cf:e2:55:b2
- aserial: 00
-
-and shows
-
- - the date the AA certificate was installed either in local time or UTC (--utc)
- - the count is always set to 1
- - the subject of the AA certificate
- - the issuer of the AA certificate
- - the serial number of the AA certificate
- - the size and keyid of the RSA public key contained in the certificate.
- - the validity of the AA certificate expressed either in local time or
- UTC (--utc). The validity is checked automatically resulting either
- in an "ok" message or a "fatal" error message.
- - the optional subjectKeyIdentifier extension which is a 20 byte SHA-1 hash
- over the AA certificate's public key.
- - the optional authorityKeyIdentifier extension which is a 20 byte SHA-1 hash
- over the public key of the issuer who signed the AA certificate.
- - the serial number of the issuer's certificate.
-
-
-The command
-
- ipsec listocspcerts [--utc]
-
-lists all OCSO signer certificates that have been either loaded from
-/etc/ipsec.d/ocspcerts/ or have been received included in the OCSP server
-response. The output has the form
-
- Feb 09 22:56:17 2005, count: 1
- subject: 'C=CH, O=Linux strongSwan, OU=OCSP, CN=ocsp.strongswan.org'
- issuer: 'C=CH, O=Linux strongSwan, CN=strongSwan Root CA'
- serial: 09
- pubkey: 2048 RSA Key AwEAAaonT
- validity: not before Nov 19 17:29:28 2004 ok
- not after Nov 18 17:29:28 2009 ok
- subjkey: 88:07:0a:b8:ae:c7:c1:07:5c:be:68:6a:c4:a5:7f:81:1f:37:b5:56
- authkey: 5d:a7:dd:70:06:51:32:7e:e7:b6:6d:b3:b5:e5:e0:60:ea:2e:4d:ef
- aserial: 00
-
-and shows
-
- - the date the OCSP signer certificate was installed either in local time
- or UTC (--utc)
- - the count is always set to 1
- - the subject of the OCSP signer certificate
- - the issuer of the OCSP signer certificate
- - the serial number of the OCSP signer certificate
- - the size and keyid of the RSA public key contained in the certificate.
- - the validity of the OCSP signer certificate expressed either in local time
- or UTC (--utc). The validity is checked automatically resulting either
- in an "ok" message or a "fatal" error message.
- - the optional subjectKeyIdentifier extension which is a 20 byte SHA-1 hash
- over the OCSP signer certificate's public key.
- - the optional authorityKeyIdentifier extension which is a 20 byte SHA-1 hash
- over the public key of the issuer who signed the OCSP certificate.
- - the serial number of the issuer's certificate.
-
-
-The command
-
- ipsec listacerts [--utc]
-
-lists all X.509 attribute certificates that have been loaded from the directory
-/etc/ipsec.d/acerts/.
-The output has the form
-
- Dec 20 13:29:56 2004
- holder: 'C=CH, O=strongSec GmbH, CN=Andreas Steffen'
- hissuer: 'C=CH, O=strongSec GmbH, CN=strongSec Root CA'
- hserial: 1e
- groups: Research, Sales
- issuer: 'C=CH, O=strongSec GmbH, CN=strongSec Authorization Authority'
- serial: 2c
- validity: not before Dec 19 14:51:38 2004 ok
- not after Dec 20 14:51:38 2004 fatal (expired)
- authkey: 56:89:b9:28:c9:1b:a0:00:7f:50:9d:ec:28:75:23:c1:1e:d1:dd:90
- aserial: 0f
-
-and shows
-
- - the date the attribute certificate was installed either in local time
- or UTC (--utc)
- - the holder of the attribute certificate
- - the issuer of holder's certificate
- - the serial number of the holder's certificate
- - the group attributes
- - the issuing Authorization Authority of the attribute certificate
- - the serial number of the attribute certificate
- - the validity of the attribute certificate expressed either in local time or
- UTC (--utc). The validity is checked automatically resulting either
- in an "ok" message or a "fatal" error message.
- - an authorityKeyIdentifier extension which is a 20 byte SHA-1 hash
- over the public key of the issuing Authorization Authority
- - the serial number of the AA certificate.
-
-
-The command
-
- ipsec listgroups [--utc]
-
-lists all group attributes either defined in right|leftgroups statements
-in ipsec.conf or contained in loaded X.509 attribute certificates.
-The output has the form
-
- Dec 20 13:29:55 2004, count: 4
- Research
- Dec 20 13:30:04 2004, count: 1
- Research New York
- Dec 20 13:29:55 2004, count: 3
- Sales
-
-and shows
-
- - the date the group attribute was first installed either in local time
- or UTC (--utc)
- - the count shows how many times the attribute is used
- - the group name
-
-
-The command
-
- ipsec listcainfos [--utc]
-
-lists the properties defined by the ca definition sections in ipsec.conf.
-The output has the form
-
- Jun 08 22:31:37 2004, "strongswan"
- authname: 'C=CH, O=Linux strongSwan, CN=strongSwan Root CA'
- ldaphost: 'ldap.strongswan.org'
- ocspuri: 'http://ocsp.strongswan.org:8880'
- distPts: 'http://crl.strongswan.org/strongswan.crl'
- 'ldap:///O=Linux strongSwan, C=CH?certificateRevocationList'
- authkey: 5d:a7:dd:70:06:51:32:7e:e7:b6:6d:b3:b5:e5:e0:60:ea:2e:4d:ef
- aserial: 00
-
-and shows
-
- - the date the CA definition was loaded either in local time or UTC (--utc)
- - the name of the ca section
- - the distinguished name of the CA
- - an optional default ldap host for the CA
- - an optional OCSP URI
- - a maximum of two optional CRL distribution points
- - the optional authorityKeyIdentifier extension which is a 20 byte SHA-1 hash
- over the public key of the CA.
- - the serial number of the CA.
-
-
-The command
-
- ipsec listcrls [--utc]
-
-lists all CRLs that have been loaded from /etc/ipsec.d/crls/.
-The output has the form
-
- Feb 11 13:37:00 2005, revoked certs: 1
- issuer: 'C=CH, O=Linux strongSwan, CN=strongSwan Root CA'
- distPts: 'http://crl.strongswan.org/strongswan.crl'
- updates: this Feb 08 07:46:29 2005
- next Mar 10 07:46:29 2005 ok
- authkey: 5d:a7:dd:70:06:51:32:7e:e7:b6:6d:b3:b5:e5:e0:60:ea:2e:4d:ef
- aserial: 00
-
-and shows
-
- - the date the CRL was installed either in local time or UTC (--utc)
- - the number revoked certificates
- - the issuer of the CRL
- - the URLs of the distribution points where the CRL can be fetched from.
- - the dates when the CRL was issued and when the next update
- is expected, respectively, expressed either in local time or
- UTC (--utc). It is automatically checked if the next update
- deadline has passed, resulting either in an "ok" message, a
- a "warning" message when strictcrlpolicy=no or a "fatal" message when
- strictcrlpolicy=yes.
- - the optional authorityKeyIdentifier extension which is a 20 byte SHA-1 hash
- over the public key of the issuer who signed the CRL. This extension is
- present in version 2 CRLs, only.
- - the serial number of the issuer's certificate.
-
-
-The command
-
-
- ipsec listocsp [--utc]
-
-lists the contents of the OCSP response cache. The output has the form
-
- issuer: 'C=CH, O=Linux strongSwan, CN=strongSwan Root CA'
- uri: 'http://ocsp.strongswan.org:8880'
- authname: 13:9d:a0:9e:f4:32:ab:8f:e2:89:56:67:fa:d0:d4:e3:35:86:71:b9
- authkey: 5d:a7:dd:70:06:51:32:7e:e7:b6:6d:b3:b5:e5:e0:60:ea:2e:4d:ef
- aserial: 00
- Feb 09 22:56:17 2005, until Feb 09 23:01:17 2005 warning (expires in 4 minutes)
- serial: 0a, good
-
-and shows
-
- - the distinguished name of the CA handled by the OCSP server
- - the http URI of the OCSP server.
- - the 20 byte SHA-1 hash of the CA's distinguished name
- - the 20 byte SHA-1 hash of the CA's public key
- - the serial number of the CA's certificate
- - a certificate status list showing
- - the time the OCSP status was received
- - an optional nextUpdate deadline (if missing the OCSP status will be
- onetime with a lifetime of 2 minutes only).
- - the serial number of the certificate
- - the status of the certificate (good, revoked, unknown)
-
-
-The command
-
- ipsec listcards [--utc]
-
-lists all smartcard records that are currently in use by Pluto.
-The output has the form
-
- Aug 17 16:47:59 2005, #1, count: 6
- slot: 0, session closed, logged out, has valid pin
- id: 45
- label: 'strongSwan'
- subject: 'C=CH, O=Linux strongSwan, CN=carol@strongswan.org'
-
-with pkcs11keepstate=no and
-
- Aug 17 16:47:59 2005, #1, count: 6
- slot: 0, session opened, logged in, has pin pad
- id: 45
- label: 'strongSwan'
- subject: 'C=CH, O=Linux strongSwan, CN=carol@strongswan.org'
-
-with pkcs11keepstate=yes and shows
-
-- the date the certificate was read from the smartcard record
-- the certificate objects are numbered starting from #1
-- the count shows how many connections and secret pin entries point
- to the smartcard record
-- the PKCS #11 slot number
-- the PKCS #11 session state: closed | opened
-- the PKCS #11 session login state: logged out | logged in
-- the status of the PIN: no pin | valid pin | invalid pin | pin pad
-- the ID of the certificate object
-- the label of the certificate object
-- the subject distinguished name of the certificate
-
-
-The command
-
- ipsec auto --listall [--utc]
-
-is equivalent to
-
- ipsec listalgs
- ipsec listpubkeys [--utc]
- ipsec listcerts [--utc]
- ipsec listcacerts [--utc]
- ipsec listaacerts [--utc]
- ipsec listocspcerts [--utc]
- ipsec listacerts [--utc]
- ipsec listgroups [--utc]
- ipsec listcainfos [--utc]
- ipsec listcrls [--utc]
- ipsec listocsp [--utc]
- ipsec listcards [--utc]
-
-
-11. Firewall support functions
- --------------------------
-
-
-11.1 Environment variables in the updown script
- ------------------------------------------
-
-strongSwan makes the following environment variables available
-in the updown script indicated by the leftupdown option:
-
-+------------------------------------------------------------------+
-| Variable Example Comment |
-|------------------------------------------------------------------|
-| $PLUTO_PEER_ID carol@strongswan.org USER_FQDN (1) |
-|------------------------------------------------------------------|
-| $PLUTO_PEER_PROTOCOL 17 udp (2) |
-|------------------------------------------------------------------|
-| $PLUTO_PEER_PORT 68 bootpc (3) |
-|------------------------------------------------------------------|
-| $PLUTO_PEER_CA C=CH, O=ACME, CN=Sales CA (4) |
-|------------------------------------------------------------------|
-| $PLUTO_MY_ID @moon.strongswan.org FQDN (1) |
-|------------------------------------------------------------------|
-| $PLUTO_MY_PROTOCOL 17 udp (2) |
-|------------------------------------------------------------------|
-| $PLUTO_MY_PORT 67 bootps (3) |
-+------------------------------------------------------------------+
-
-(1) $PLUTO_PEER_ID/$PLUTO_MY_ID contain the IDs of the two ends
- of an established connection. In our examples these
- correspond to the strings defined by rightid and leftid,
- respectively.
-
-(2) $PLUTO_PEER_PROTOCOL/$PLUTO_MY_PROTOCOL contain the protocol
- defined by the rightprotoport and leftprotoport options,
- respectively. Both variables contain the same protocol value.
- The variables take on the value '0' if no protocol has been defined.
-
-(3) $PLUTO_PEER_PORT/$PLUTO_MY_PORT contain the ports defined by
- the rightprotoport and leftprotoport options, respectively.
- The variables take on the value '0' if no port has been defined.
-
-(4) $PLUTO_PEER_CA contains the distinguished name of the CA that
- issued the peer's certificate.
-
-
-11.2 Automatic insertion and deletion of iptables firewall rules
- -----------------------------------------------------------
-
-Starting with strongswan-2.7.0, the default _updown script automatically inserts
-and deletes dynamic iptables firewall rules upon the establishment or teardown,
-respectively, of an IPsec security association. This new feature is activated
-with the line
-
- leftfirewall=yes
-
-and can be used when the following prerequisites are fulfilled:
-
- - Linux 2.4.x kernel, KLIPS IPsec stack, and arbitrary iptables version.
- Filtering of tunneled traffic is based on ipsecN interfaces.
-
- - Linux 2.6.16 kernel or newer, native NETKEY IPsec stack, and
- iptables-1.3.5 or newer. Filtering of tunneled traffic is based on
- IPsec policy matching rules.
-
-If you define a local client subnet with a netmask larger than /32 behind
-the gateway then the automatically inserted FORWARD iptables rules will
-not allow to access the internal IP address of the host although it is
-part of the client subnet definition. If you want additional INPUT and
-OUTPUT iptables rules to be inserted, so that the host itself can be accessed
-then add the following line:
-
- lefthostaccess=yes
-
-The _updown script also features a logging facility which will register the
-creation (+) and the expiration (-) of each successfully established VPN
-connection in a special syslog file in the following concise and easily
-readable format:
-
-Jul 19 18:58:38 moon vpn:
- + @carol.strongswan.org 192.168.0.100 -- 192.168.0.1 == 10.1.0.0/16
-Jul 19 22:15:17 moon vpn:
- - @carol.strongswan.org 192.168.0.100 -- 192.168.0.1 == 10.1.0.0/16
-
-
-11.3 Sample Linux 2.6 updown script for iptables < 1.3.5
- ---------------------------------------------------
-
-If you are using a Linux 2.6 kernel older than 2.6.16 or an iptables version
-older than 1.3.5 then the IPsec policy matching rules will not be available.
-In order to make sure that only tunneled packets are accepted, a mark can be
-set on incoming ESP packets. This "ESP" mark will be retained on the
-decapsulated packet so that iptables rules inserted by the updown script can
-check on the presence of this mark. For this purpose the template located in
-
- programs/_updown_espmark
-
-can be used. Store a copy of _updown_espmark e.g. in /etc/ipsec.updown and load
-the script with the line
-
- leftupdown=/etc/updown.ipsec.
-
-In addition for the dynamic updown script to work the following static iptables rules
-must be applied:
-
- iptables -t mangle -A INPUT -p 50 -j MARK --set-mark 50
-
-
-12. Authentication with raw RSA public keys
- ---------------------------------------
-
-FreeS/WAN, as it is available from www.freeswan.org does public key
-authentication with raw RSA public keys that are directly defined in
-/etc/ipsec.conf
-
- rightrsasigkey=0sAq4c....
-
-When version 1.x of standard FreeS/WAN receives a certificate request (CR),
-it immediately drops the negotiation because it does not know how to answer
-the request. As a workaround strongSwan does not send a CR if the RSA
-key has been statically loaded using [right/left]rsasigkey. A problem
-remains with roadwarriors initiating a connection. Since strongSwan
-does not know the identity of the initiating peer in advance, it will always
-send a CR, causing the rupture of the IKE negotiation if the peer is a
-version 1.x FreeS/WAN host. To circumvent this problem the configuration
-parameter 'nocrsend' can be set in the config setup section of /etc/ipsec.conf:
-
- config setup:
- nocrsend=yes
-
-With this entry no certificate request is sent in any connection.
-The default setting is nocrsend=no.
-
-
-13. Authentication with OpenPGP certificates
- ----------------------------------------
-
-strongSwan also supports RSA based authentication using OpenPGP
-certificates and OpenPGP V3 fingerprints used as an KEY_ID identifier.
-
-
-13.1 OpenPGP certificates
- --------------------
-
-OpenPGP certificates containing RSA public keys can now directly be loaded
-in ASCII armored PGP format using the leftcert and rightcert parameters
-in /etc/ipsec.conf:
-
- conn pgp
- right=%any
- righcert=peerCert.asc
- left=%defaultroute
- leftcert=gatewayCert.asc
-
-The peer certificate must be stored locally (the default directory is
-/etc/ipsec.d/certs) since currently no trust can be established for
-PGP certificates received from a peer via the IKE protocol.
-
-
-13.2 OpenPGP private keys
- --------------------
-
-PGP private keys in unencrypted form can now directly be loaded in ASCII
-armored PGP format via an entry in /etc/ipsec.secrets:
-
- : RSA gatewayKey.asc
-
-Existing IDEA-encrypted RSA private keys can be unlocked with GnuPG and
-the IDEA extension (see http://www.gnupg.org/gph/en/pgp2x.html) using
-the commands
-
- gpg --import gatewayCert.asc
-
- gpg --allow-secret-key-import --import gatewayKey.asc
-
- gpg --edit-key <gateway ID>
- > passwd #change to empty password
- > save
-
- gpg -a --export-secret-key <gateway ID> gatewayKey.asc
-
-
-13.3 Monitoring functions
- --------------------
-
-The command ipsec listcerts shows all loaded PGP certificates
-in the following format:
-
- Aug 28 09:51:55 2002, count: 1
- fingerprint: 0x1ccfca12d93467ffa9d5093d87a465dc
- pubkey: 1024 RSA Key ARHso6uKQ
- created: Aug 27 08:51:39 2002
- until: --- -- --:--:-- ---- ok (expires never)
-
-The entries are
-
- - the date the certificate was loaded either in local time or UTC (--utc)
- - the V3 fingerprint consisting of the 16 byte MD5 hash of the public key
- which is used as an ID of type KEY_ID
- - the modulus size of the RSA key in bits
- - a keyID consisting of 9 base64 symbols representing the public exponent
- and the most significant bits of the modulus
- - the creation date of the public key (extracted from the certificate)
- - the optional expiration date of the public key (extracted from the
- certificate)
-
-
-13.4 Suppression of certificate request messages
- -------------------------------------------
-
-PGPnet configured to work with OpenPGP certificates aborts the IKE
-negotiation when it receives a X.509 certificate. Therefore it is recommended
-(mandatory for roadwarrior connections) to set
-
- config setup:
- nocrsend=yes
-
-in /etc/ipsec.conf.
-
-
-14. Additional Features
- -------------------
-
-
-14.1 Authentication and encryption algorithms
- ----------------------------------------
-
-strongSwan supports the following suite of encryption and authentication
-algorithms for both IKE and ESP payloads.
-
-+------------------------------------------------------------------+
-| IKE algorithms (negotiated in Phase 1 Main Mode) |
-+------------------------------------------------------------------+
-| Encryption algorithms: 3des, aes, serpent, twofish, blowfish |
-|------------------------------------------------------------------|
-| Hash algorithms: md5, sha, sha2 |
-|------------------------------------------------------------------|
-| DH groups: 1024, 1536, 2048, 3072, 4096, 6144, 8192 |
-+------------------------------------------------------------------+
-
-NOTE: For IKE the SHA-1 algorithm is denoted by "sha"
-
-The cryptographic IKE algorithms listed above are a fixed part of the
-strongSwan distribution. Particular algorithms can be added or removed
-in the "programs/pluto/alg" directory.
-
-+------------------------------------------------------------------+
-| ESP algorithms (negotiated in Phase 2 Quick Mode) |
-+------------------------------------------------------------------+
-| Encryption algorithms: 3des, aes, serpent, twofish, blowfish |
-|------------------------------------------------------------------|
-| Hash algorithms: md5, sha1, sha2 |
-|------------------------------------------------------------------|
-| PFS groups: 1024, 1536, 2048, 3072, 4096, 6144, 8192 |
-+------------------------------------------------------------------+
-
-The cryptographic ESP algorithms listed above are a fixed part of the
-strongSwan distribution. If your Linux 2.4 or 2.6 kernel includes the
-CryptoAPI then additional ESP algorithms can be added or deleted as
-kernel modules.
-
-The IKE and ESP cryptographic algorithms to be proposed to the peer
-as an initiator can be specified on a per connection basis in the form
-
-conn normal
- ...
- ike=aes128-sha-modp1536,3des-sha-modp1536
- esp=aes128-sha1,3des-sha1
- ...
-
-or if you are more paranoid
-
-conn paranoid
- ...
- ike=aes256-sha2_512-modp2048
- esp=aes256-sha2_512
- ...
-
-If the the "ike" and "esp" configuration parameters are missing in
-ipsec.conf, then the default settings
-
- ike=3des-md5-modp1536,3des-sha-modp1536,\
- 3des-md5-modp1024,3des-sha-modp1024
- esp=3des-md5,3des-sha1
-
-arre implicitly assumed. The 3DES encryption algorithm and the MD5 and
-SHA-1 hash algorithms are hardcoded into strongSwan and cannot be removed.
-
-If Perfect Forward Secrecy (PFS is desired), then a PFS group can be
-optionally specified:
-
-conn make_sure
- ...
- pfs=yes
- pfsgroup=modp2048,modp1536
- ...
-
-If the "pfs" parameter is missing then "pfs=yes" is assumed by default.
-This means that PFS must be disabled explicitly by setting "pfs=no".
-
-If the "pfsgroup" parameter is missing then the default is
-
- pfsgroup=<Phase1 DH group>
-
-The "ike" and "esp" parameters are used to formulate one or several
-transform proposals to the peer if the strongSwan VPN host is the initiator.
-Attention! As a responder the first proposal from the peer is accepted that
-is supported the by one of the registered algorithms listed by the command
-
- ipsec listalgs
-
-If the responder wants to restrict the allowed cipher suites the '!' flag
-can be used to do so. The configuration
-
-conn normal_but_strict
- ...
- ike=aes128-sha-modp1536,3des-sha-modp1536!
- esp=aes128-sha1,3des-sha1!
- ...
-
-will only permit the listed algorithms defined above but no other methods
-even if they might be supported by the responder.
-
-
-14.2 NAT traversal
- -------------
-
-Currently please refer to README.NAT-Traversal document in the strongSwan
-distribution.
-
-
-14.3 Dead peer detection
- --------------------
-
-strongSwan implements the RFC 3706 Dead Peer Detection (DPD) keep-alive
-scheme. If an established IPsec SA has been idle (i.e. without any traffic)
-for N seconds (dpddelay=N) then strongSwan side sends a "hello" message
-(R_U_THERE) and the peer replies with an acknowledge message (R_U_THERE_ACK).
-If no response is received, the R_U_THERE messages are repeated until a DPD
-timeout of M seconds (dpdtimeout=M) has elapsed. If still no traffic or
-R_U_THERE_ACK packets were received, the peer is declared to be dead and all
-SAs belonging to a common Phase 1 SA are deleted.
-
-DPD support is tuneable on a per connection basis by using the dpdaction,
-dpddelay and dpdtimeout directives:
-
- conn roadwarrior
- right=%any
- left=%defaultroute
- leftsubnet=10.1.0.0/16
- dpdaction=clear
-
- conn net-to-net
- right=192.168.0.2
- rightsubnet=10.2.0.0/16
- left=%defaultroute
- leftsubnet=10.1.0.0/16
- dpdaction=hold
- dpddelay=60
- dpdtimeout=500
-
-In the first example dpdaction=clear activates the DPD mechanism under the
-condition that the peer supports RFC 3706. The values dpddelay=30s and
-dpdtimeout=120s are assumed by default in the absence of these parameters, so
-that during idle periods an R_U_THERE packet is sent every 30 seconds. If no
-traffic or a no R_U_THERE_ACK packet is received from the peer within a
-120 second time span, the peer will be declared dead and all SAs and associated
-eroutes will be cleared.
-
-In the second example R_U_THERE packets are sent every 60 seconds and the
-parameter setting dpdaction=hold will put the eroute of the ruptured connection
-into a %trap state, so that when new outgoing traffic will occur, the
-correspondig connection will be automatically renegotiated as soon as the
-peer is up again.
-
-It is recommended to use dpdaction=hold for statically defined connections and
-dpdaction=clear for dynamic roadwarrior connections. The default value is
-dpdaction=none, which disables DPD.
-
-
-14.4 IKE Mode Config Pull Mode
- -------------------------
-
-The IKE Mode Config protocol <draft-ietf-ipsec-isakmp-mode-cfg-04.txt> allows
-the dynamic assignment of virtual IP addresses and optional DNS and WINS server
-information to IPsec clients. As a default the "Mode Config Pull Mode" is
-used where the client actively sends a Mode Config request to the server
-in order to obtain a virtual IP. The server answers with a Mode Config reply
-message containing the requested information.
-
-Client side configuration (carol):
-
- conn home
- right=192.168.0.1
- rightsubnet=10.1.0.0/16
- rightid=@moon.strongswan.org
- left=%defaultroute
- leftsourceip=%modeconfig
- leftcert=carolCert.pem
- leftid=carol@strongswan.org
- auto=start
-
-Server side configuration (moon):
-
- conn roadwarrior
- right=%any
- rightid=carol@strongswan.org
- rightsourceip=10.3.0.1
- left=%defaultroute
- leftsubnet=10.1.0.0/16
- leftcert=moonCert.pem
- leftid=@moon.strongswan.org
- auto=add
-
-The wildcard %modeconfig or %modecfg used in the leftsourceip parameter of the
-client will trigger a Mode Config request. Currently the server will return
-the virtual IP address defined by the rightsourceip parameter. In the future
-an LDAP-based lookup mechanism will be supported.
-
-
-14.5 IKE Mode Config Push Mode
- -------------------------
-
-Cisco VPN equipment uses the alternative "Mode Config Push Mode" where the
-initiating clients waits for the server to push down a virtual address via
-a Mode Config set message. The receipt is acknowledged by the client with a
-Mode Config ack message.
-
-Mode Config Push Mode is activated by the parameter
-
- modeconfig=push
-
-as part of the connection definition in ipsec.conf. The default value is
-modeconfig=pull.
-
-
-14.6 XAUTH - Extended Authentication
- -------------------------------
-
-The XAUTH protocol <draft-beaulieu-ike-xauth-02.txt> allows an extended
-client authentication using e.g. a username/password paradigm in addition
-to the IKE Main Mode authentication. Thus XAUTH can be used in conjunction
-with Pre-Shared Keys (PSK) by defining
-
- authby=xauthpsk
-
-or with RSA signatures
-
- authby=xauthrsasig
-
-in the connection definition, correspondingly. strongSwan can act either as
-an XAUTH client with
-
- xauth=client
-
-or as an XAUTH server with
-
- xauth=server
-
-with xauth=client being the default value. strongSwan integrates a default
-implementation where the XAUTH user credentials are stored on both the
-server and the client in the /etc/ipsec.secrets file, using the syntax
-
- : XAUTH john "rT6q!V2p"
-
-The client must not have more than one XAUTH entry whereas the server can
-contain an unlimited number of user credentials in ipsec.secrets.
-
-Either the prompting on the client side or the verification of the user
-credentials on the server side can be implemented as a customized XAUTH
-dynamic library module. The corresponding library interface is defined
-by the pluto/xauth.h header file.
-
-
-15. Copyright statement and acknowledgements
- ----------------------------------------
-
-
- FreeS/WAN version base system:
-
- Copyright (c) 1999-2004
- Henry Spencer, Richard Guy Briggs,
- D. Hugh Redelmeier, Sandy Harris, Claudia Schmeing,
- Michael Richardson, Angelos D. Keromytis, John Ioannidis,
-
- NAT-Traversal, ipsec starter, Delete SA and Notification messages:
-
- Copyright (c) 2002-2003, Mathieu Lafon
-
- Additional cryptoalgorithms (AES, etc):
-
- Copyright (c) 2002-2003, JuanJo Ciarlante
-
- Dead Peer Detection:
-
- Copyright (c) 2002-2004
- Ken Bantoft, JuanJo Ciarlante, Philip Craig,
- Pawel Krawczyk, Srinvasan Venkataraman
-
- Porting to Linux 2.6 kernel:
-
- Copyright (c) 2003, Herbert Xu
-
- Dynamic CRL fetching:
-
- Copyright (c) 2002, Stephane Laroche
-
- IKE Mode Config and XAUTH protocol:
-
- Copyright (c) 2001-2002, Colubris Networks
-
- Virtual IP and source routing:
-
- Copyright (c) 2003, Tuomo Soini
-
- Port and protocol selectors for outbound traffic:
-
- Copyright (c) 2002, Stephen J. Bevan
-
- PGPnet-RSA parts of patch:
-
- Copyright (c) 2000, Kai Martius
-
- X.509, OCSP and smartcard functionality:
-°
- Copyright (c) 2000, Andreas Hess, Patric Lichtsteiner, Roger Wegmann
- Copyright (c) 2001, Marco Bertossa, Andreas Schleiss
- Copyright (c) 2002, Uli Galizzi, Ariane Seiler, Mario Strasser
- Copyright (c) 2002, Martin Berner, Lukas Suter
- Copyright (c) 2003, Christoph Gysin, Simon Zwahlen
- Copyright (c) 2004, David Buechi, Michael Meier
- Copyright (c) 2000-2005, Andreas Steffen
-
- Zurich University of Applied Sciences in Winterthur, Switzerland
-
- scepclient:
-
- Copyright (c) 2005, Jan Hutter, Martin Willi
- Copyright (c) 2005-2007, Andreas Steffen
-
- University of Applied Sciences in Rapperswil, Switzerland
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version. See http://www.fsf.org/copyleft/gpl.txt.
-
- This program is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
- for more details.
------------------------------------------------------------------------------
-
-This file is RCSID $Id: README,v 1.38 2007/01/14 18:16:51 as Exp $
-
projects / thirdparty / strongswan.git / blobdiff