.TH STRONGSWAN.CONF 5 "2011-07-26" "@IPSEC_VERSION@" "strongSwan"
.SH NAME
strongswan.conf \- strongSwan configuration file
.SH DESCRIPTION
While the
.IR ipsec.conf (5)
configuration file is well suited to define IPsec related configuration
parameters, it is not useful for other strongSwan applications to read options
from this file.
The file is hard to parse and only
.I ipsec starter
is capable of doing so. As the number of components of the strongSwan project
is continually growing, a more flexible configuration file was needed, one that
is easy to extend and can be used by all components. With strongSwan 4.2.1
.IR strongswan.conf (5)
was introduced which meets these requirements.

.SH SYNTAX
The format of the strongswan.conf file consists of hierarchical
.B sections
and a list of
.B key/value pairs
in each section. Each section has a name, followed by C-Style curly brackets
defining the section body. Each section body contains a set of subsections
and key/value pairs:
.PP
.EX
	settings := (section|keyvalue)*
	section  := name { settings }
	keyvalue := key = value\\n
.EE
.PP
Values must be terminated by a newline.
.PP
Comments are possible using the \fB#\fP-character, but be careful: The parser
implementation is currently limited and does not like brackets in comments.
.PP
Section names and keys may contain any printable character except:
.PP
.EX
	. { } # \\n \\t space
.EE
.PP
An example file in this format might look like this:
.PP
.EX
	a = b
	section-one {
		somevalue = asdf
		subsection {
			othervalue = xxx
		}
		# yei, a comment
		yetanother = zz
	}
	section-two {
		x = 12
	}
.EE
.PP
Indentation is optional, you may use tabs or spaces.

.SH INCLUDING FILES
Using the
.B include
statement it is possible to include other files into strongswan.conf, e.g.
.PP
.EX
	include /some/path/*.conf
.EE
.PP
If the file name is not an absolute path, it is considered to be relative
to the directory of the file containing the include statement. The file name
may include shell wildcards (see
.IR sh (1)).
Also, such inclusions can be nested.
.PP
Sections loaded from included files
.I extend
previously loaded sections; already existing values are
.IR replaced .
It is important to note that settings are added relative to the section the
include statement is in.
.PP
As an example, the following three files result in the same final
config as the one given above:
.PP
.EX
	a = b
	section-one {
		somevalue = before include
		include include.conf
	}
	include other.conf

include.conf:
	# settings loaded from this file are added to section-one
	# the following replaces the previous value
	somevalue = asdf
	subsection {
		othervalue = yyy
	}
	yetanother = zz

other.conf:
	# this extends section-one and subsection
	section-one {
		subsection {
			# this replaces the previous value
			othervalue = xxx
		}
	}
	section-two {
		x = 12
	}
.EE

.SH READING VALUES
Values are accessed using a dot-separated section list and a key.
With reference to the example above, accessing
.B section-one.subsection.othervalue
will return
.BR xxx .

.SH DEFINED KEYS
The following keys are currently defined (using dot notation). The default
value (if any) is listed in brackets after the key.

.SS attest section
.TP
.BR attest.database
Path to database with file measurement information
.TP
.BR attest.load
Plugins to load in ipsec attest tool
.SS charon section
.TP
.BR charon.block_threshold " [5]"
Maximum number of half-open IKE_SAs for a single peer IP
.TP
.BR charon.close_ike_on_child_failure " [no]"
Close the IKE_SA if setup of the CHILD_SA along with IKE_AUTH failed
.TP
.BR charon.cookie_threshold " [10]"
Number of half-open IKE_SAs that activate the cookie mechanism
.TP
.BR charon.dns1
.TQ
.BR charon.dns2
DNS servers assigned to peer via configuration payload (CP)
.TP
.BR charon.dos_protection " [yes]"
Enable Denial of Service protection using cookies and aggressiveness checks
.TP
.BR charon.filelog
Section to define file loggers, see LOGGER CONFIGURATION
.TP
.BR charon.flush_auth_cfg " [no]"

.TP
.BR charon.half_open_timeout " [30]"
Timeout in seconds for connecting IKE_SAs (also see IKE_SA_INIT DROPPING).
.TP
.BR charon.hash_and_url " [no]"
Enable hash and URL support
.TP
.BR charon.ignore_routing_tables
A list of routing tables to be excluded from route lookup
.TP
.BR charon.ikesa_table_segments " [1]"
Number of exclusively locked segments in the hash table
.TP
.BR charon.ikesa_table_size " [1]"
Size of the IKE_SA hash table
.TP
.BR charon.inactivity_close_ike " [no]"
Whether to close IKE_SA if the only CHILD_SA closed due to inactivity
.TP
.BR charon.init_limit_half_open " [0]"
Limit new connections based on the current number of half open IKE_SAs (see
IKE_SA_INIT DROPPING).
.TP
.BR charon.init_limit_job_load " [0]"
Limit new connections based on the number of jobs currently queued for
processing (see IKE_SA_INIT DROPPING).
.TP
.BR charon.install_routes " [yes]"
Install routes into a separate routing table for established IPsec tunnels
.TP
.BR charon.install_virtual_ip " [yes]"
Install virtual IP addresses
.TP
.BR charon.keep_alive " [20s]"
NAT keep alive interval
.TP
.BR charon.load
Plugins to load in the IKEv2 daemon charon
.TP
.BR charon.max_packet " [10000]"
Maximum packet size accepted by charon
.TP
.BR charon.multiple_authentication " [yes]"
Enable multiple authentication exchanges (RFC 4739)
.TP
.BR charon.nbns1
.TQ
.BR charon.nbns2
WINS servers assigned to peer via configuration payload (CP)
.TP
.BR charon.process_route " [yes]"
Process RTM_NEWROUTE and RTM_DELROUTE events
.TP
.BR charon.receive_delay " [0]"
Delay for receiving packets, to simulate larger RTT
.TP
.BR charon.receive_delay_response " [yes]"
Delay response messages
.TP
.BR charon.receive_delay_request " [yes]"
Delay request messages
.TP
.BR charon.receive_delay_type " [0]"
Specific IKEv2 message type to delay, 0 for any
.TP
.BR charon.replay_window " [32]"
Size of the AH/ESP replay window, in packets.
.TP
.BR charon.retransmit_base " [1.8]"
Base to use for calculating exponential back off, see IKEv2 RETRANSMISSION
.TP
.BR charon.retransmit_timeout " [4.0]
Timeout in seconds before sending first retransmit
.TP
.BR charon.retransmit_tries " [5]"
Number of times to retransmit a packet before giving up
.TP
.BR charon.reuse_ikesa " [yes]
Initiate CHILD_SA within existing IKE_SAs
.TP
.BR charon.routing_table
Numerical routing table to install routes to
.TP
.BR charon.routing_table_prio
Priority of the routing table
.TP
.BR charon.send_delay " [0]"
Delay for sending packets, to simulate larger RTT
.TP
.BR charon.send_delay_response " [yes]"
Delay response messages
.TP
.BR charon.send_delay_request " [yes]"
Delay request messages
.TP
.BR charon.send_delay_type " [0]"
Specific IKEv2 message type to delay, 0 for any
.TP
.BR charon.send_vendor_id " [no]
Send strongSwan vendor ID payload
.TP
.BR charon.syslog
Section to define syslog loggers, see LOGGER CONFIGURATION
.TP
.BR charon.threads " [16]"
Number of worker threads in charon
.SS charon.plugins subsection
.TP
.BR charon.plugins.android.loglevel " [1]"
Loglevel for logging to Android specific logger
.TP
.BR charon.plugins.attr
Section to specify arbitrary attributes that are assigned to a peer via
configuration payload (CP)
.TP
.BR charon.plugins.dhcp.identity_lease " [no]"
Derive user-defined MAC address from hash of IKEv2 identity
.TP
.BR charon.plugins.dhcp.server " [255.255.255.255]"
DHCP server unicast or broadcast IP address
.TP
.BR charon.plugins.duplicheck.enable " [yes]"
enable loaded duplicheck plugin
.TP
.BR charon.plugins.eap-aka.request_identity " [yes]"

.TP
.BR charon.plugins.eap-aka-3ggp2.seq_check

.TP
.BR charon.plugins.eap-gtc.pam_service " [login]"
PAM service to be used for authentication

.TP
.BR charon.plugins.eap-peap.fragment_size " [1024]"
Maximum size of an EAP-PEAP packet
.TP
.BR charon.plugins.eap-peap.max_message_count " [32]"
Maximum number of processed EAP-PEAP packets
.TP
.BR charon.plugins.eap-peap.include_length " [no]"
Include length in non-fragmented EAP-PEAP packets
.TP
.BR charon.plugins.eap-peap.phase2_method " [mschapv2]"
Phase2 EAP client authentication method
.TP
.BR charon.plugins.eap-peap.phase2_piggyback " [no]"
Phase2 EAP Identity request piggybacked by server onto TLS Finished message
.TP
.BR charon.plugins.eap-peap.phase2_tnc " [no]"
Start phase2 EAP TNC protocol after successful client authentication
.TP
.BR charon.plugins.eap-peap.request_peer_auth " [no]"
Request peer authentication based on a client certificate

.TP
.BR charon.plugins.eap-radius.accounting " [no]"
Send RADIUS accounting information to RADIUS servers.
.TP
.BR charon.plugins.eap-radius.class_group " [no]"
Use the
.I class
attribute sent in the RADIUS-Accept message as group membership information that
is compared to the groups specified in the
.B rightgroups
option in
.B ipsec.conf (5).
.TP
.BR charon.plugins.eap-radius.eap_start " [no]"
Send EAP-Start instead of EAP-Identity to start RADIUS conversation
.TP
.BR charon.plugins.eap-radius.filter_id " [no]"
If the RADIUS
.I tunnel_type
attribute with value
.B ESP
is received, use the
.I filter_id
attribute sent in the RADIUS-Accept message as group membership information that
is compared to the groups specified in the
.B rightgroups
option in
.B ipsec.conf (5).
.TP
.BR charon.plugins.eap-radius.id_prefix
Prefix to EAP-Identity, some AAA servers use a IMSI prefix to select the
EAP method
.TP
.BR charon.plugins.eap-radius.nas_identifier " [strongSwan]"
NAS-Identifier to include in RADIUS messages
.TP
.BR charon.plugins.eap-radius.port " [1812]"
Port of RADIUS server (authentication)
.TP
.BR charon.plugins.eap-radius.secret
Shared secret between RADIUS and NAS
.TP
.BR charon.plugins.eap-radius.server
IP/Hostname of RADIUS server
.TP
.BR charon.plugins.eap-radius.servers
Section to specify multiple RADIUS servers. The
.BR nas_identifier ,
.BR secret ,
.B sockets
and
.B port
options can be specified for each server. A server's IP/Hostname can be
configured using the
.B address
option. For each RADIUS server a priority can be specified using the
.BR preference " [0]"
option.
.TP
.BR charon.plugins.eap-radius.sockets " [1]"
Number of sockets (ports) to use, increase for high load
.TP
.BR charon.plugins.eap-sim.request_identity " [yes]"

.TP
.BR charon.plugins.eap-simaka-sql.database

.TP
.BR charon.plugins.eap-simaka-sql.remove_used

.TP
.BR charon.plugins.eap-tls.fragment_size " [1024]"
Maximum size of an EAP-TLS packet
.TP
.BR charon.plugins.eap-tls.max_message_count " [32]"
Maximum number of processed EAP-TLS packets
.TP
.BR charon.plugins.eap-tls.include_length " [yes]"
Include length in non-fragmented EAP-TLS packets
.TP
.BR charon.plugins.eap-tnc.fragment_size " [50000]"
Maximum size of an EAP-TNC packet
.TP
.BR charon.plugins.eap-tnc.max_message_count " [10]"
Maximum number of processed EAP-TNC packets
.TP
.BR charon.plugins.eap-tnc.include_length " [yes]"
Include length in non-fragmented EAP-TNC packets
.TP
.BR charon.plugins.eap-ttls.fragment_size " [1024]"
Maximum size of an EAP-TTLS packet
.TP
.BR charon.plugins.eap-ttls.max_message_count " [32]"
Maximum number of processed EAP-TTLS packets
.TP
.BR charon.plugins.eap-ttls.include_length " [yes]"
Include length in non-fragmented EAP-TTLS packets
.TP
.BR charon.plugins.eap-ttls.phase2_method " [md5]"
Phase2 EAP client authentication method
.TP
.BR charon.plugins.eap-ttls.phase2_piggyback " [no]"
Phase2 EAP Identity request piggybacked by server onto TLS Finished message
.TP
.BR charon.plugins.eap-ttls.phase2_tnc " [no]"
Start phase2 EAP TNC protocol after successful client authentication
.TP
.BR charon.plugins.eap-ttls.request_peer_auth " [no]"
Request peer authentication based on a client certificate
.TP
.BR charon.plugins.ha.fifo_interface " [yes]"

.TP
.BR charon.plugins.ha.heartbeat_delay " [1000]"

.TP
.BR charon.plugins.ha.heartbeat_timeout " [2100]"

.TP
.BR charon.plugins.ha.local

.TP
.BR charon.plugins.ha.monitor " [yes]"

.TP
.BR charon.plugins.ha.pools

.TP
.BR charon.plugins.ha.remote

.TP
.BR charon.plugins.ha.resync " [yes]"

.TP
.BR charon.plugins.ha.secret

.TP
.BR charon.plugins.ha.segment_count " [1]"

.TP
.BR charon.plugins.led.activity_led

.TP
.BR charon.plugins.led.blink_time " [50]"

.TP
.BR charon.plugins.kernel-klips.ipsec_dev_count " [4]"
Number of ipsecN devices
.TP
.BR charon.plugins.kernel-klips.ipsec_dev_mtu " [0]"
Set MTU of ipsecN device
.TP
.BR charon.plugins.load-tester
Section to configure the load-tester plugin, see LOAD TESTS
.TP
.BR charon.plugins.resolve.file " [/etc/resolv.conf]"
File where to add DNS server entries
.TP
.BR charon.plugins.resolve.resolvconf.iface_prefix " [lo.inet.ipsec.]"
Prefix used for interface names sent to resolvconf(8). The nameserver address
is appended to this prefix to make it unique.  The result has to be a valid
interface name according to the rules defined by resolvconf.  Also, it should
have a high priority according to the order defined in interface-order(5).
.TP
.BR charon.plugins.sql.database
Database URI for charons SQL plugin
.TP
.BR charon.plugins.sql.loglevel " [-1]"
Loglevel for logging to SQL database
.TP
.BR charon.plugins.stroke.ignore_missing_ca_basic_constraint " [no]"
Treat certificates in ipsec.d/cacerts and ipsec.conf ca sections as CA
certificates even if they don't contain a CA basic constraint.
.TP
.BR charon.plugins.stroke.max_concurrent " [4]"
Maximum number of stroke messages handled concurrently
.TP
.BR charon.plugins.tnc-ifmap.device_name
Unique name of strongSwan as a PEP and/or PDP device
.TP
.BR charon.plugins.tnc-ifmap.key_file
Concatenated client certificate and private key
.TP
.BR charon.plugins.tnc-ifmap.password
Authentication password of strongSwan MAP client
.TP
.BR charon.plugins.tnc-ifmap.server_cert
Certificate of MAP server
.TP
.BR charon.plugins.tnc-ifmap.ssl_passphrase
Passphrase protecting the private key
.TP
.BR charon.plugins.tnc-ifmap.username
Authentication username of strongSwan MAP client
.TP
.BR charon.plugins.tnc-imc.preferred_language " [en]"
Preferred language for TNC recommendations
.TP
.BR charon.plugins.tnc-pdp.method " [ttls]"
EAP tunnel method to be used
.TP
.BR charon.plugins.tnc-pdp.port " [1812]"
RADIUS server port the strongSwan PDP is listening on
.TP
.BR charon.plugins.tnc-pdp.secret
Shared RADIUS secret between strongSwan PDP and NAS
.TP
.BR charon.plugins.tnc-pdp.server
name of the strongSwan PDP as contained in the AAA certificate
.TP
.BR charon.plugins.whitelist.enable " [yes]"
enable loaded whitelist plugin
.SS libstrongswan section
.TP
.BR libstrongswan.crypto_test.bench " [no]"

.TP
.BR libstrongswan.crypto_test.bench_size " [1024]"

.TP
.BR libstrongswan.crypto_test.bench_time " [50]"

.TP
.BR libstrongswan.crypto_test.on_add " [no]"
Test crypto algorithms during registration
.TP
.BR libstrongswan.crypto_test.on_create " [no]"
Test crypto algorithms on each crypto primitive instantiation
.TP
.BR libstrongswan.crypto_test.required " [no]"
Strictly require at least one test vector to enable an algorithm
.TP
.BR libstrongswan.crypto_test.rng_true " [no]"
Whether to test RNG with TRUE quality; requires a lot of entropy
.TP
.BR libstrongswan.dh_exponent_ansi_x9_42 " [yes]"
Use ANSI X9.42 DH exponent size or optimum size matched to cryptographical
strength
.TP
.BR libstrongswan.ecp_x_coordinate_only " [yes]"
Compliance with the errata for RFC 4753
.TP
.BR libstrongswan.integrity_test " [no]"
Check daemon, libstrongswan and plugin integrity at startup
.TP
.BR libstrongswan.leak_detective.detailed " [yes]"
Includes source file names and line numbers in leak detective output
.TP
.BR libstrongswan.processor.priority_threads
Subsection to configure the number of reserved threads per priority class
see JOB PRIORITY MANAGEMENT
.TP
.BR libstrongswan.x509.enforce_critical " [yes]"
Discard certificates with unsupported or unknown critical extensions
.SS libstrongswan.plugins subsection
.TP
.BR libstrongswan.plugins.attr-sql.database
Database URI for attr-sql plugin used by charon and pluto
.TP
.BR libstrongswan.plugins.attr-sql.lease_history " [yes]"
Enable logging of SQL IP pool leases
.TP
.BR libstrongswan.plugins.gcrypt.quick_random " [no]"
Use faster random numbers in gcrypt; for testing only, produces weak keys!
.TP
.BR libstrongswan.plugins.openssl.engine_id " [pkcs11]"
ENGINE ID to use in the OpenSSL plugin
.TP
.BR libstrongswan.plugins.pkcs11.modules
List of available PKCS#11 modules
.TP
.BR libstrongswan.plugins.pkcs11.use_dh " [no]"
Whether the PKCS#11 modules should be used for DH and ECDH (see use_ecc option)
.TP
.BR libstrongswan.plugins.pkcs11.use_ecc " [no]"
Whether the PKCS#11 modules should be used for ECDH and ECDSA public key
operations. ECDSA private keys can be used regardless of this option
.TP
.BR libstrongswan.plugins.pkcs11.use_hasher " [no]"
Whether the PKCS#11 modules should be used to hash data
.TP
.BR libstrongswan.plugins.pkcs11.use_pubkey " [no]"
Whether the PKCS#11 modules should be used for public key operations, even for
keys not stored on tokens
.TP
.BR libstrongswan.plugins.pkcs11.use_rng " [no]"
Whether the PKCS#11 modules should be used as RNG
.SS libtnccs section
.TP
.BR libtnccs.tnc_config " [/etc/tnc_config]"
TNC IMC/IMV configuration directory
.SS libimcv section
.TP
.BR libimcv.debug_level " [1]"
Debug level for a stand-alone libimcv library
.TP
.BR libimcv.stderr_quiet " [no]"
Disable output to stderr with a stand-alone libimcv library
.SS libimcv plugins section
.TP
.BR libimcv.plugins.imc-attestation.platform_info
Information on operating system and hardware platform
.TP
.BR libimcv.plugins.imc-attestation.aik_blob
AIK encrypted private key blob file
.TP
.BR libimcv.plugins.imc-attestation.aik_cert
AIK certificate file
.TP
.BR libimcv.plugins.imc-attestation.aik_key
AIK public key file
.TP
.BR libimcv.plugins.imv-attestation.nonce_len " [20]"
DH nonce length
.TP
.BR libimcv.plugins.imv-attestation.use_quote2 " [yes]"
Use Quote2 AIK signature instead of Quote signature
.TP
.BR libimcv.plugins.imv-attestation.cadir
Path to directory with AIK cacerts
.TP
.BR libimcv.plugins.imv-attestation.database
Path to database with file measurement information
.TP
.BR libimcv.plugins.imv-attestation.dh_group " [ecp256]"
Preferred Diffie-Hellman group
.TP
.BR libimcv.plugins.imv-attestation.hash_algorithm " [sha256]"
Preferred measurement hash algorithm
.TP
.BR libimcv.plugins.imv-attestation.min_nonce_len " [0]"
DH minimum nonce length
.TP
.BR libimcv.plugins.imv-attestation.platform_info
Information on operating system and hardware platform
.TP
.BR libimcv.plugins.imv-scanner.closed_port_policy " [yes]"
By default all ports must be closed (yes) or can be open (no)
.TP
.BR libimcv.plugins.imv-scanner.tcp_ports
List of TCP ports that can be open or must be closed
.TP
.BR libimcv.plugins.imv-scanner.udp_ports
List of UDP ports that can be open or must be closed
.TP
.BR libimcv.plugins.imc-test.additional_ids " [0]"
Number of additional IMC IDs
.TP
.BR libimcv.plugins.imc-test.command " [none]"
Command to be sent to the Test IMV
.TP
.BR libimcv.plugins.imc-test.retry " [no]"
Do a handshake retry
.TP
.BR libimcv.plugins.imc-test.retry_command
Command to be sent to the Test IMV in the handshake retry
.TP
.BR libimcv.plugins.imv-test.rounds " [0]"
Number of IMC-IMV retry rounds
.SS libtls section
.TP
.BR libtls.cipher
List of TLS encryption ciphers
.TP
.BR libtls.key_exchange
List of TLS key exchange methods
.TP
.BR libtls.mac
List of TLS MAC algorithms
.TP
.BR libtls.suites
List of TLS cipher suites
.SS manager section
.TP
.BR manager.database
Credential database URI for manager
.TP
.BR manager.debug " [no]"
Enable debugging in manager
.TP
.BR manager.load
Plugins to load in manager
.TP
.BR manager.socket
FastCGI socket of manager, to run it statically
.TP
.BR manager.threads " [10]"
Threads to use for request handling
.TP
.BR manager.timeout " [15m]"
Session timeout for manager
.SS mediation client section
.TP
.BR medcli.database
Mediation client database URI
.TP
.BR medcli.dpd " [5m]"
DPD timeout to use in mediation client plugin
.TP
.BR medcli.rekey " [20m]"
Rekeying time on mediation connections in mediation client plugin
.SS mediation server section
.TP
.BR medsrv.database
Mediation server database URI
.TP
.BR medsrv.debug " [no]"
Debugging in mediation server web application
.TP
.BR medsrv.dpd " [5m]"
DPD timeout to use in mediation server plugin
.TP
.BR medsrv.load
Plugins to load in mediation server plugin
.TP
.BR medsrv.password_length " [6]"
Minimum password length required for mediation server user accounts
.TP
.BR medsrv.rekey " [20m]"
Rekeying time on mediation connections in mediation server plugin
.TP
.BR medsrv.socket
Run Mediation server web application statically on socket
.TP
.BR medsrv.threads " [5]"
Number of thread for mediation service web application
.TP
.BR medsrv.timeout " [15m]"
Session timeout for mediation service
.SS openac section
.TP
.BR openac.load
Plugins to load in ipsec openac tool
.SS pki section
.TP
.BR pki.load
Plugins to load in ipsec pki tool
.SS pluto section
.TP
.BR pluto.dns1
.TQ
.BR pluto.dns2
DNS servers assigned to peer via Mode Config
.TP
.BR pluto.load
Plugins to load in IKEv1 pluto daemon
.TP
.BR pluto.nbns1
.TQ
.BR pluto.nbns2
WINS servers assigned to peer via Mode Config
.TP
.BR pluto.threads " [4]"
Number of worker threads in pluto
.SS pluto.plugins section
.TP
.BR pluto.plugins.attr
Section to specify arbitrary attributes that are assigned to a peer via
Mode Config
.TP
.BR charon.plugins.kernel-klips.ipsec_dev_count " [4]"
Number of ipsecN devices
.TP
.BR charon.plugins.kernel-klips.ipsec_dev_mtu " [0]"
Set MTU of ipsecN device
.SS pool section
.TP
.BR pool.load
Plugins to load in ipsec pool tool
.SS scepclient section
.TP
.BR scepclient.load
Plugins to load in ipsec scepclient tool
.SS starter section
.TP
.BR starter.load
Plugins to load in starter
.TP
.BR starter.load_warning " [yes]"
Disable charon/pluto plugin load option warning

.SH LOGGER CONFIGURATION
The options described below provide a much more flexible way to configure
loggers for the IKEv2 daemon charon than using the
.B charondebug
option in
.BR ipsec.conf (5).
.PP
.B Please note
that if any loggers are specified in strongswan.conf,
.B charondebug
does not have any effect.
.PP
There are currently two types of loggers defined:
.TP
.B File loggers
Log directly to a file and are defined by specifying the full path to the
file as subsection in the
.B charon.filelog
section. To log to the console the two special filenames
.BR stdout " and " stderr
can be used.
.TP
.B Syslog loggers
Log into a syslog facility and are defined by specifying the facility to log to
as the name of a subsection in the
.B charon.syslog
section. The following facilities are currently supported:
.BR daemon " and " auth .
.PP
Multiple loggers can be defined for each type with different log verbosity for
the different subsystems of the daemon.
.SS Options
.TP
.BR charon.filelog.<filename>.default " [1]"
.TQ
.BR charon.syslog.<facility>.default
Specifies the default loglevel to be used for subsystems for which no specific
loglevel is defined.
.TP
.BR charon.filelog.<filename>.<subsystem> " [<default>]"
.TQ
.BR charon.syslog.<facility>.<subsystem>
Specifies the loglevel for the given subsystem.
.TP
.BR charon.filelog.<filename>.append " [yes]"
If this option is enabled log entries are appended to the existing file.
.TP
.BR charon.filelog.<filename>.flush_line " [no]"
Enabling this option disables block buffering and enables line buffering.
.TP
.BR charon.filelog.<filename>.ike_name " [no]"
.TQ
.BR charon.syslog.<facility>.ike_name
Prefix each log entry with the connection name and a unique numerical
identifier for each IKE_SA.
.TP
.BR charon.filelog.<filename>.time_format
Prefix each log entry with a timestamp. The option accepts a format string as
passed to
.BR strftime (3).
.TP
.BR charon.syslog.identifier
Global identifier used for an
.BR openlog (3)
call, prepended to each log message by syslog.  If not configured,
.BR openlog (3)
is not called, so the value will depend on system defaults (often the program
name).

.SS Subsystems
.TP
.B dmn
Main daemon setup/cleanup/signal handling
.TP
.B mgr
IKE_SA manager, handling synchronization for IKE_SA access
.TP
.B ike
IKE_SA
.TP
.B chd
CHILD_SA
.TP
.B job
Jobs queueing/processing and thread pool management
.TP
.B cfg
Configuration management and plugins
.TP
.B knl
IPsec/Networking kernel interface
.TP
.B net
IKE network communication
.TP
.B asn
Low-level encoding/decoding (ASN.1, X.509 etc.)
.TP
.B enc
Packet encoding/decoding encryption/decryption operations
.TP
.B tls
libtls library messages
.TP
.B lib
libstrongwan library messages
.TP
.B tnc
Trusted Network Connect
.TP
.B imc
Integrity Measurement Collector
.TP
.B imv
Integrity Measurement Verifier
.TP
.B pts
Platform Trust Service
.SS Loglevels
.TP
.B -1
Absolutely silent
.TP
.B 0
Very basic auditing logs, (e.g. SA up/SA down)
.TP
.B 1
Generic control flow with errors, a good default to see whats going on
.TP
.B 2
More detailed debugging control flow
.TP
.B 3
Including RAW data dumps in Hex
.TP
.B 4
Also include sensitive material in dumps, e.g. keys
.SS Example
.PP
.EX
	charon {
		filelog {
			/var/log/charon.log {
				time_format = %b %e %T
				append = no
				default = 1
			}
			stderr {
				ike = 2
				knl = 3
				ike_name = yes
			}
		}
		syslog {
			# enable logging to LOG_DAEMON, use defaults
			daemon {
			}
			# minimalistic IKE auditing logging to LOG_AUTHPRIV
			auth {
				default = -1
				ike = 0
			}
		}
	}
.EE

.SH JOB PRIORITY MANAGEMENT
Some operations in the IKEv2 daemon charon are currently implemented
synchronously and blocking. Two examples for such operations are communication
with a RADIUS server via EAP-RADIUS, or fetching CRL/OCSP information during
certificate chain verification. Under high load conditions, the thread pool may
run out of available threads, and some more important jobs, such as liveness
checking, may not get executed in time.
.PP
To prevent thread starvation in such situations job priorities were introduced.
The job processor will reserve some threads for higher priority jobs, these
threads are not available for lower priority, locking jobs.
.SS Implementation
Currently 4 priorities have been defined, and they are used in charon as
follows:
.TP
.B CRITICAL
Priority for long-running dispatcher jobs.
.TP
.B HIGH
INFORMATIONAL exchanges, as used by liveness checking (DPD).
.TP
.B MEDIUM
Everything not HIGH/LOW, including IKE_SA_INIT processing.
.TP
.B LOW
IKE_AUTH message processing. RADIUS and CRL fetching block here
.PP
Although IKE_SA_INIT processing is computationally expensive, it is explicitly
assigned to the MEDIUM class. This allows charon to do the DH exchange while
other threads are blocked in IKE_AUTH. To prevent the daemon from accepting more
IKE_SA_INIT requests than it can handle, use IKE_SA_INIT DROPPING.
.PP
The thread pool processes jobs strictly by priority, meaning it will consume all
higher priority jobs before looking for ones with lower priority. Further, it
reserves threads for certain priorities. A priority class having reserved
.I n
threads will always have
.I n
threads available for this class (either currently processing a job, or waiting
for one).
.SS Configuration
To ensure that there are always enough threads available for higher priority
tasks, threads must be reserved for each priority class.
.TP
.BR libstrongswan.processor.priority_threads.critical " [0]"
Threads reserved for CRITICAL priority class jobs
.TP
.BR libstrongswan.processor.priority_threads.high " [0]"
Threads reserved for HIGH priority class jobs
.TP
.BR libstrongswan.processor.priority_threads.medium " [0]"
Threads reserved for MEDIUM priority class jobs
.TP
.BR libstrongswan.processor.priority_threads.low " [0]"
Threads reserved for LOW priority class jobs
.PP
Let's consider the following configuration:
.PP
.EX
	libstrongswan {
		processor {
			priority_threads {
				high = 1
				medium = 4
			}
		}
	}
.EE
.PP
With this configuration, one thread is reserved for HIGH priority tasks. As
currently only liveness checking and stroke message processing is done with
high priority, one or two threads should be sufficient.
.PP
The MEDIUM class mostly processes non-blocking jobs. Unless your setup is
experiencing many blocks in locks while accessing shared resources, threads for
one or two times the number of CPU cores is fine.
.PP
It is usually not required to reserve threads for CRITICAL jobs. Jobs in this
class rarely return and do not release their thread to the pool.
.PP
The remaining threads are available for LOW priority jobs. Reserving threads
does not make sense (until we have an even lower priority).
.SS Monitoring
To see what the threads are actually doing, invoke
.IR "ipsec statusall" .
Under high load, something like this will show up:
.PP
.EX
	worker threads: 2 or 32 idle, 5/1/2/22 working,
		job queue: 0/0/1/149, scheduled: 198
.EE
.PP
From 32 worker threads,
.IP 2
are currently idle.
.IP 5
are running CRITICAL priority jobs (dispatching from sockets, etc.).
.IP 1
is currently handling a HIGH priority job. This is actually the thread currently
providing this information via stroke.
.IP 2
are handling MEDIUM priority jobs, likely IKE_SA_INIT or CREATE_CHILD_SA
messages.
.IP 22
are handling LOW priority jobs, probably waiting for an EAP-RADIUS response
while processing IKE_AUTH messages.
.PP
The job queue load shows how many jobs are queued for each priority, ready for
execution. The single MEDIUM priority job will get executed immediately, as
we have two spare threads reserved for MEDIUM class jobs.

.SH IKE_SA_INIT DROPPING
If a responder receives more connection requests per seconds than it can handle,
it does not make sense to accept more IKE_SA_INIT messages. And if they are
queued but can't get processed in time, an answer might be sent after the
client has already given up and restarted its connection setup. This
additionally increases the load on the responder.
.PP
To limit the responder load resulting from new connection attempts, the daemon
can drop IKE_SA_INIT messages just after reception. There are two mechanisms to
decide if this should happen, configured with the following options:
.TP
.BR charon.init_limit_half_open " [0]"
Limit based on the number of half open IKE_SAs. Half open IKE_SAs are SAs in
connecting state, but not yet established.
.TP
.BR charon.init_limit_job_load " [0]"
Limit based on the number of jobs currently queued for processing (sum over all
job priorities).
.PP
The second limit includes load from other jobs, such as rekeying. Choosing a
good value is difficult and depends on the hardware and expected load.
.PP
The first limit is simpler to calculate, but includes the load from new
connections only. If your responder is capable of negotiating 100 tunnels/s, you
might set this limit to 1000. The daemon will then drop new connection attempts
if generating a response would require more than 10 seconds. If you are
allowing for a maximum response time of more than 30 seconds, consider adjusting
the timeout for connecting IKE_SAs
.RB ( charon.half_open_timeout ).
A responder, by default, deletes an IKE_SA if the initiator does not establish
it within 30 seconds. Under high load, a higher value might be required.

.SH LOAD TESTS
To do stability testing and performance optimizations, the IKEv2 daemon charon
provides the load-tester plugin. This plugin allows to setup thousands of
tunnels concurrently against the daemon itself or a remote host.
.PP
.B WARNING:
Never enable the load-testing plugin on productive systems. It provides
preconfigured credentials and allows an attacker to authenticate as any user.
.SS Options
.TP
.BR charon.plugins.load-tester.child_rekey " [600]"
Seconds to start CHILD_SA rekeying after setup
.TP
.BR charon.plugins.load-tester.delay " [0]"
Delay between initiatons for each thread
.TP
.BR charon.plugins.load-tester.delete_after_established " [no]"
Delete an IKE_SA as soon as it has been established
.TP
.BR charon.plugins.load-tester.dpd_delay " [0]"
DPD delay to use in load test
.TP
.BR charon.plugins.load-tester.dynamic_port " [0]"
Base port to be used for requests (each client uses a different port)
.TP
.BR charon.plugins.load-tester.eap_password " [default-pwd]"
EAP secret to use in load test
.TP
.BR charon.plugins.load-tester.enable " [no]"
Enable the load testing plugin
.TP
.BR charon.plugins.load-tester.fake_kernel " [no]"
Fake the kernel interface to allow load-testing against self
.TP
.BR charon.plugins.load-tester.ike_rekey " [0]"
Seconds to start IKE_SA rekeying after setup
.TP
.BR charon.plugins.load-tester.init_limit " [0]"
Global limit of concurrently established SAs during load test
.TP
.BR charon.plugins.load-tester.initiators " [0]"
Number of concurrent initiator threads to use in load test
.TP
.BR charon.plugins.load-tester.initiator_auth " [pubkey]"
Authentication method(s) the intiator uses
.TP
.BR charon.plugins.load-tester.initiator_id
Initiator ID used in load test
.TP
.BR charon.plugins.load-tester.iterations " [1]"
Number of IKE_SAs to initate by each initiator in load test
.TP
.BR charon.plugins.load-tester.pool
Provide INTERNAL_IPV4_ADDRs from a named pool
.TP
.BR charon.plugins.load-tester.preshared_key " [default-psk]"
Preshared key to use in load test
.TP
.BR charon.plugins.load-tester.proposal " [aes128-sha1-modp768]"
IKE proposal to use in load test
.TP
.BR charon.plugins.load-tester.remote " [127.0.0.1]"
Address to initiation connections to
.TP
.BR charon.plugins.load-tester.responder_auth " [pubkey]"
Authentication method(s) the responder uses
.TP
.BR charon.plugins.load-tester.responder_id
Responder ID used in load test
.TP
.BR charon.plugins.load-tester.request_virtual_ip " [no]"
Request an INTERNAL_IPV4_ADDR from the server
.TP
.BR charon.plugins.load-tester.shutdown_when_complete " [no]"
Shutdown the daemon after all IKE_SAs have been established
.SS Configuration details
For public key authentication, the responder uses the
.B \(dqCN=srv, OU=load-test, O=strongSwan\(dq
identity. For the initiator, each connection attempt uses a different identity
in the form
.BR "\(dqCN=c1-r1, OU=load-test, O=strongSwan\(dq" ,
where the first number inidicates the client number, the second the
authentication round (if multiple authentication is used).
.PP
For PSK authentication, FQDN identities are used. The server uses
.BR srv.strongswan.org ,
the client uses an identity in the form
.BR c1-r1.strongswan.org .
.PP
For EAP authentication, the client uses a NAI in the form
.BR 100000000010001@strongswan.org .
.PP
To configure multiple authentication, concatenate multiple methods using, e.g.
.EX
	initiator_auth = pubkey|psk|eap-md5|eap-aka
.EE
.PP
The responder uses a hardcoded certificate based on a 1024-bit RSA key.
This certificate additionally serves as CA certificate. A peer uses the same
private key, but generates client certificates on demand signed by the CA
certificate. Install the Responder/CA certificate on the remote host to
authenticate all clients.
.PP
To speed up testing, the load tester plugin implements a special Diffie-Hellman
implementation called modpnull. By setting
.EX
	proposal = aes128-sha1-modpnull
.EE
this wicked fast DH implementation is used. It does not provide any security
at all, but allows to run tests without DH calculation overhead.
.SS Examples
.PP
In the simplest case, the daemon initiates IKE_SAs against itself using the
loopback interface. This will actually establish double the number of IKE_SAs,
as the daemon is initiator and responder for each IKE_SA at the same time.
Installation of IPsec SAs would fails, as each SA gets installed twice. To
simulate the correct behavior, a fake kernel interface can be enabled which does
not install the IPsec SAs at the kernel level.
.PP
A simple loopback configuration might look like this:
.PP
.EX
	charon {
		# create new IKE_SAs for each CHILD_SA to simulate
		# different clients
		reuse_ikesa = no
		# turn off denial of service protection
		dos_protection = no

		plugins {
			load-tester {
				# enable the plugin
				enable = yes
				# use 4 threads to initiate connections
				# simultaneously
				initiators = 4
				# each thread initiates 1000 connections
				iterations = 1000
				# delay each initiation in each thread by 20ms
				delay = 20
				# enable the fake kernel interface to
				# avoid SA conflicts
				fake_kernel = yes
			}
		}
	}
.EE
.PP
This will initiate 4000 IKE_SAs within 20 seconds. You may increase the delay
value if your box can not handle that much load, or decrease it to put more
load on it. If the daemon starts retransmitting messages your box probably can
not handle all connection attempts.
.PP
The plugin also allows to test against a remote host. This might help to test
against a real world configuration. A connection setup to do stress testing of
a gateway might look like this:
.PP
.EX
	charon {
		reuse_ikesa = no
		threads = 32

		plugins {
			load-tester {
				enable = yes
				# 10000 connections, ten in parallel
				initiators = 10
				iterations = 1000
				# use a delay of 100ms, overall time is:
				# iterations * delay = 100s
				delay = 100
				# address of the gateway
				remote = 1.2.3.4
				# IKE-proposal to use
				proposal = aes128-sha1-modp1024
				# use faster PSK authentication instead
				# of 1024bit RSA
				initiator_auth = psk
				responder_auth = psk
				# request a virtual IP using configuration
				# payloads
				request_virtual_ip = yes
				# enable CHILD_SA every 60s
				child_rekey = 60
			}
		}
	}
.EE

.SH IKEv2 RETRANSMISSION
Retransmission timeouts in the IKEv2 daemon charon can be configured globally
using the three keys listed below:
.PP
.RS
.nf
.BR charon.retransmit_base " [1.8]"
.BR charon.retransmit_timeout " [4.0]"
.BR charon.retransmit_tries " [5]"
.fi
.RE
.PP
The following algorithm is used to calculate the timeout:
.PP
.EX
	relative timeout = retransmit_timeout * retransmit_base ^ (n-1)
.EE
.PP
Where
.I n
is the current retransmission count.
.PP
Using the default values, packets are retransmitted in:

.TS
l r r
---
lB r r.
Retransmission	Relative Timeout	Absolute Timeout
1	4s	4s
2	7s	11s
3	13s	24s
4	23s	47s
5	42s	89s
giving up	76s	165s
.TE

.SH FILES
/etc/strongswan.conf

.SH SEE ALSO
ipsec.conf(5), ipsec.secrets(5), ipsec(8)
.SH HISTORY
Written for the
.UR http://www.strongswan.org
strongSwan project
.UE
by Tobias Brunner, Andreas Steffen and Martin Willi.