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STRONGSWAN.CONF(5)		   strongSwan		      STRONGSWAN.CONF(5)

NAME
     strongswan.conf - strongSwan configuration file

DESCRIPTION
     While  the  ipsec.conf(5) configuration file is well suited to define IPsec
     related configuration parameters, it is not useful for other strongSwan ap-
     plications to read options from this file.  The file is hard to  parse  and
     only  ipsec  starter is capable of doing so. As the number of components of
     the strongSwan project is continually growing, a more  flexible  configura-
     tion  file  was  needed,  one that is easy to extend and can be used by all
     components. With strongSwan 4.2.1 strongswan.conf(5) was  introduced  which
     meets these requirements.

SYNTAX
     The  format  of  the strongswan.conf file consists of hierarchical sections
     and a list of 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:

	  settings := (section|keyvalue)*
	  section  := name { settings }
	  keyvalue := key = value\n

     Values must be terminated by a newline.

     Comments are possible using the #-character.

     Section names and keys may contain any printable character except:

	  . , : { } = " # \n \t space

     An example file in this format might look like this:

	  a = b
	  section-one {
	       somevalue = asdf
	       subsection {
		    othervalue = xxx
	       }
	       # yei, a comment
	       yetanother = zz
	  }
	  section-two {
	       x = 12
	  }

     Indentation is optional, you may use tabs or spaces.

NUMBER FORMATS
     Options that define an integer value can be specified as decimal  (the  de-
     fault)  or  hexadecimal  ("0x"  prefix, upper- or lowercase letters are ac-
     cepted).  Locale-dependent strings (e.g. the  thousands  separator  of  the
     current locale) may also be accepted in locales other than "C".

     Options that define a floating-point value can be specified as decimal (the
     default)  or  hexadecimal ("0x" prefix, upper- or lowercase letters are ac-
     cepted).  The radix character (decimal separator) in either case is locale-
     dependent, usually ".".

TIME FORMATS
     Unless stated otherwise, options that define a time are specified	in  sec-
     onds.  The "s", "m", "h" and "d" suffixes may be used to automatically con-
     vert values given in seconds, minutes, hours or days (for instance, instead
     of  configuring  a  rekey	time  of 4 hours as "14400" seconds, "4h" may be
     used).

     There are some global options that don't accept these suffixes as they  are
     configured  as integer values in seconds or milliseconds, or even as float-
     ing-point numbers (e.g. the retransmission timeout).  Options  that  accept
     the suffixes have a corresponding default value.

REFERENCING OTHER SECTIONS
     It  is possible to inherit settings and sections from another section. This
     feature is mainly useful in swanctl.conf (which uses the same file format).
     The syntax is as follows:

	  section    := name : references { settings }
	  references := absname[, absname]*
	  absname    := name[.name]*

     All key/value pairs and all subsections of the referenced sections will  be
     inherited by the section that references them via their absolute name. Val-
     ues  may  be  overridden  in the section or any of its sub-sections (use an
     empty assignment to clear a value so its default value, if  any,  will  ap-
     ply).  It	is  currently  not  possible  to  limit  the  inclusion level or
     clear/remove inherited sub-sections.

     If the order is important (e.g. for auth rounds in a connection,  if  round
     is not used), it should be noted that inherited settings/sections will fol-
     low  those  defined in the current section (if multiple sections are refer-
     enced, their settings are enumerated left to right).

     References are evaluated dynamically at runtime, so referring  to	sections
     later in the config file or included via other files is no problem.

     Here is an example of how this might look like:

	  conn-defaults {
	       # default settings for all conns (e.g. a cert, or IP pools)
	  }
	  eap-defaults {
	       # defaults if eap is used (e.g. a remote auth round)
	  }
	  child-defaults {
	       # defaults for child configs (e.g. traffic selectors)
	  }
	  connections {
	       conn-a : conn-defaults, eap-defaults {
		    # set/override stuff specific to this connection
		    children {
			 child-a : child-defaults {
			      # set/override stuff specific to this child
			 }
		    }
	       }
	       conn-b : conn-defaults {
		    # set/override stuff specific to this connection
		    children {
			 child-b : child-defaults {
			      # set/override stuff specific to this child
			 }
		    }
	       }
	       conn-c : connections.conn-a {
		    # everything is inherited, including everything conn-a
		    # already inherits from the sections it and its
		    # sub-section reference
	       }
	  }

INCLUDING FILES
     Using  the  include  statement  it  is possible to include other files into
     strongswan.conf, e.g.

	  include /some/path/*.conf

     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 sh(1)).  Also, such inclusions can be
     nested.

     Sections loaded from included files extend previously loaded sections;  al-
     ready  existing values are replaced.  It is important to note that settings
     are added relative to the section the include statement is in.

     As an example, the following three files result in the same final config as
     the one given above:

	  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
	  }

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

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

     aikgen.load []
	    Plugins to load in ipsec aikgen tool.

     attest.database []
	    File measurement information database URI. If it  contains	a  pass-
	    word, make sure to adjust the permissions of the config file accord-
	    ingly.

     attest.load []
	    Plugins to load in ipsec attest tool.

     charon
	    Options for the charon IKE daemon.

	    Note:  Many  of the options in this section also apply to charon-cmd
	    and other charon derivatives.  Just use their respective name  (e.g.
	    charon-cmd instead of charon).  For many options defaults can be de-
	    fined in the libstrongswan section.

     charon.accept_private_algs [no]
	    Deliberately  violate  the	IKE standard's requirement and allow the
	    use of private algorithm identifiers, even if the  peer  implementa-
	    tion is unknown.

     charon.accept_unencrypted_mainmode_messages [no]
	    Accept unencrypted ID and HASH payloads in IKEv1 Main Mode.

	    Some  implementations  send the third Main Mode message unencrypted,
	    probably to find the PSKs for the specified ID  for  authentication.
	    This  is  very similar to Aggressive Mode, and has the same security
	    implications: A passive attacker can sniff the negotiated  Identity,
	    and start brute forcing the PSK using the HASH payload.

	    It is recommended to keep this option to no, unless you know exactly
	    what  the implications are and require compatibility to such devices
	    (for example, some SonicWall boxes).

     charon.block_threshold [5]
	    Maximum  number  of   half-open   IKE_SAs	(including   unprocessed
	    IKE_SA_INITs) for a single peer IP.

     charon.cache_crls [no]
	    Whether Certificate Revocation Lists (CRLs) fetched via HTTP or LDAP
	    should be saved under a unique file name derived from the public key
	    of	the  Certification  Authority (CA) to ${sysconfdir}/ipsec.d/crls
	    (stroke) or ${sysconfdir}/swanctl/x509crl (vici), respectively.

     charon.cert_cache [yes]
	    Whether relations in validated certificate chains should  be  cached
	    in memory.

     charon.check_current_path [no]
	    By	default,  after  detecting  any changes to interfaces and/or ad-
	    dresses no action is taken if the current path to  the  remote  peer
	    still  looks  usable.  Enabling this option will use DPD to check if
	    the path actually still works, or, for instance,  the  peer  removed
	    the  state	after a longer phase without connectivity.  It will also
	    trigger a MOBIKE update if NAT  mappings  were  removed  during  the
	    downtime.

     charon.cisco_flexvpn [no]
	    Send the Cisco FlexVPN vendor ID payload, which is required in order
	    to make Cisco brand devices allow negotiating a local traffic selec-
	    tor  (from strongSwan's point of view) that is not the assigned vir-
	    tual IP address if such an address is  requested  by     strongSwan.
	    Sending the Cisco FlexVPN vendor ID prevents the peer from narrowing
	    the initiator's local traffic selector and allows it to e.g. negoti-
	    ate  a  TS	of 0.0.0.0/0 == 0.0.0.0/0 instead.  This has been tested
	    with a "tunnel mode ipsec ipv4" Cisco template but should also  work
	    for GRE encapsulation.

     charon.cisco_unity [no]
	    Send Cisco Unity vendor ID payload (IKEv1 only).

     charon.close_ike_on_child_failure [no]
	    Close  the	IKE_SA	if  setup  of  the  CHILD_SA along with IKE_AUTH
	    failed.

     charon.cookie_threshold [30]
	    Number of half-open  IKE_SAs  (including  unprocessed  IKE_SA_INITs)
	    that activate the cookie mechanism.

     charon.cookie_threshold_ip [3]
	    Number of half-open IKE_SAs (including unprocessed IKE_SA_INITs) for
	    a single peer IP that activate the cookie  mechanism.

     charon.crypto_test.bench [no]
	    Benchmark crypto algorithms and order them by efficiency.

     charon.crypto_test.bench_size [1024]
	    Buffer size used for crypto benchmark.

     charon.crypto_test.bench_time [50]
	    Time in ms during which crypto algorithm performance is measured.

     charon.crypto_test.on_add [no]
	    Test  crypto  algorithms  during registration (requires test vectors
	    provided by the test-vectors plugin).

     charon.crypto_test.on_create [no]
	    Test crypto algorithms on each crypto primitive instantiation.

     charon.crypto_test.required [no]
	    Strictly require at least one test vector to enable an algorithm.

     charon.crypto_test.rng_true [no]
	    Whether to test RNG with TRUE quality; requires a lot of entropy.

     charon.delete_rekeyed [no]
	    Delete CHILD_SAs right after they got  successfully  rekeyed  (IKEv1
	    only). Reduces the number of stale CHILD_SAs in scenarios with a lot
	    of	rekeyings.  However,  this might cause problems with implementa-
	    tions that continue to use rekeyed SAs until they expire.

     charon.delete_rekeyed_delay [5]
	    Delay in seconds until inbound IPsec SAs are deleted after rekeyings
	    (IKEv2 only). To process delayed  packets  the  inbound  part  of  a
	    CHILD_SA  is  kept	installed up to the configured number of seconds
	    after it got replaced during a rekeying. If set to	0  the	CHILD_SA
	    will  be  kept  installed until it expires (if no lifetime is set it
	    will be destroyed immediately).

     charon.dh_exponent_ansi_x9_42 [yes]
	    Use ANSI X9.42 DH exponent size or optimum size matched  to  crypto-
	    graphic strength.

     charon.dlopen_use_rtld_now [no]
	    Use RTLD_NOW with dlopen when loading plugins and IMV/IMCs to reveal
	    missing symbols immediately.

     charon.dns1 []
	    DNS server assigned to peer via configuration payload (CP).

     charon.dns2 []
	    DNS server assigned to peer via configuration payload (CP).

     charon.dos_protection [yes]
	    Enable Denial of Service protection using cookies and aggressiveness
	    checks.

     charon.filelog
	    Section   to  define  file	loggers,  see  LOGGER  CONFIGURATION  in
	    strongswan.conf(5).

     charon.filelog.<name>
	    <name> may be the full path to the log  file  if  it  only	contains
	    characters	permitted in section names. Is ignored if path is speci-
	    fied.

     charon.filelog.<name>.<subsystem> [<default>]
	    Loglevel for a specific subsystem.

     charon.filelog.<name>.append [yes]
	    If this option is enabled log entries are appended to  the	existing
	    file.

     charon.filelog.<name>.default [1]
	    Specifies  the  default loglevel to be used for subsystems for which
	    no specific loglevel is defined.

     charon.filelog.<name>.flush_line [no]
	    Enabling this option  disables  block  buffering  and  enables  line
	    buffering.

     charon.filelog.<name>.ike_name [no]
	    Add  the  connection  name and a unique numerical identifier for the
	    current IKE_SA to each log entry if available.

     charon.filelog.<name>.json [no]
	    Enables writing each log entry as a JSON object  to  the  file.  The
	    properties	are "time" (if `time_format` is set), "thread", "group",
	    "level" and "msg".	Newlines, double quotes and backslashes are  es-
	    caped  in the latter. If `ike_name` is enabled, "ikesa-uniqueid" and
	    "ikesa-name" are added to the object if available.	The  `log_level`
	    option does not apply if this is enabled.

     charon.filelog.<name>.log_level [no]
	    Add the log level of each message after the subsystem (e.g. [IKE2]).

     charon.filelog.<name>.path []
	    Optional  path  to the log file. Overrides the section name. Must be
	    used if the path contains characters that aren't allowed in  section
	    names.

     charon.filelog.<name>.time_format []
	    Prefix  each log entry with a timestamp. The option accepts a format
	    string as passed to strftime(3).

     charon.filelog.<name>.time_precision []
	    Add the milliseconds (ms) or microseconds (us)  within  the  current
	    second  after  the	timestamp  (separated  by  a dot, so time_format
	    should end with %S or %T). By default, nothing is added.

     charon.flush_auth_cfg [no]
	    If enabled objects used during authentication (certificates, identi-
	    ties etc.)	are released to free memory once  an  IKE_SA  is  estab-
	    lished.  Enabling  this  might conflict with plugins that later need
	    access to e.g. the used certificates.

     charon.follow_redirects [yes]
	    Whether to follow IKEv2 redirects (RFC 5685).

     charon.force_eap_only_authentication [no]
	    Violate RFC 5998 and use EAP-only authentication even  if  the  peer
	    did not send an EAP_ONLY_AUTHENTICATION notify during IKE_AUTH.

     charon.fragment_size [1280]
	    Maximum  size  (complete  IP  datagram  size in bytes) of a sent IKE
	    fragment when using proprietary IKEv1 or standardized IKEv2 fragmen-
	    tation, defaults to 1280 (use 0 for address family specific  default
	    values, which uses a lower value for IPv4).  Unless overridden, this
	    limit is used for both IPv4 and IPv6 if specified.

     charon.fragment_size_v4 [charon.fragment_size]
	    Maximum  size  (complete  IPv4 datagram size in bytes) of a sent IKE
	    fragment when using proprietary IKEv1 or standardized IKEv2 fragmen-
	    tation.

     charon.fragment_size_v6 [charon.fragment_size]
	    Maximum size (complete IPv6 datagram size in bytes) of  a  sent  IKE
	    fragment when using proprietary IKEv1 or standardized IKEv2 fragmen-
	    tation.

     charon.group []
	    Name of the group the daemon changes to after startup.

     charon.half_open_timeout [30]
	    Timeout  in  seconds  for  connecting  IKE_SAs (also see IKE_SA_INIT
	    DROPPING).

     charon.hash_and_url [no]
	    Enable hash and URL support.

     charon.host_resolver.max_threads [3]
	    Maximum number of concurrent resolver threads (they  are  terminated
	    if unused).

     charon.host_resolver.min_threads [0]
	    Minimum number of resolver threads to keep around.

     charon.i_dont_care_about_security_and_use_aggressive_mode_psk [no]
	    If	enabled responders are allowed to use IKEv1 Aggressive Mode with
	    pre-shared keys, which is discouraged due to security concerns  (of-
	    fline attacks on the openly transmitted hash of the PSK).

     charon.ignore_acquire_ts [no]
	    If	this is disabled the traffic selectors from the kernel's acquire
	    events, which are derived from the triggering packet, are  prepended
	    to	the  traffic  selectors from the configuration for IKEv2 connec-
	    tion. By enabling this, such specific traffic selectors will be  ig-
	    nored and only the ones in the config will be sent. This always hap-
	    pens  for IKEv1 connections as the protocol only supports one set of
	    traffic selectors per CHILD_SA.

     charon.ignore_routing_tables []
	    A space-separated list of routing tables to be excluded  from  route
	    lookups.

     charon.ikesa_limit [0]
	    Maximum  number  of IKE_SAs that can be established at the same time
	    before new connection attempts are blocked.

     charon.ikesa_table_segments [1]
	    Number of exclusively locked segments in the hash table.

     charon.ikesa_table_size [1]
	    Size of the IKE_SA hash table.

     charon.imcv
	    Defaults for options in this section can be configured  in	the  li-
	    bimcv section.

     charon.imcv.assessment_result [yes]
	    Whether IMVs send a standard IETF Assessment Result attribute.

     charon.imcv.database []
	    Global IMV policy database URI. If it contains a password, make sure
	    to adjust the permissions of the config file accordingly.

     charon.imcv.os_info.default_password_enabled [no]
	    Manually set whether a default password is enabled

     charon.imcv.os_info.name []
	    Manually set the name of the client OS (e.g. Ubuntu).

     charon.imcv.os_info.version []
	    Manually set the version of the client OS (e.g. 12.04 i686).

     charon.imcv.policy_script [ipsec _imv_policy]
	    Script called for each TNC connection to generate IMV policies.

     charon.inactivity_close_ike [no]
	    Whether  to close IKE_SA if the only CHILD_SA closed due to inactiv-
	    ity.

     charon.init_limit_half_open [0]
	    Limit new connections based on  the  current  number  of  half  open
	    IKE_SAs, see IKE_SA_INIT DROPPING in strongswan.conf(5).

     charon.init_limit_job_load [0]
	    Limit  new	connections based on the number of jobs currently queued
	    for processing (see IKE_SA_INIT DROPPING).

     charon.initiator_only [no]
	    Causes charon daemon to ignore IKE initiation requests.

     charon.install_routes [yes]
	    Install routes into a separate routing table for  established  IPsec
	    tunnels.

     charon.install_virtual_ip [yes]
	    Install virtual IP addresses.

     charon.install_virtual_ip_on []
	    The  name  of  the interface on which virtual IP addresses should be
	    installed. If not specified the addresses will be installed  on  the
	    outbound interface.

     charon.integrity_test [no]
	    Check daemon, libstrongswan and plugin integrity at startup.

     charon.interfaces_ignore []
	    A comma-separated list of network interfaces that should be ignored,
	    if interfaces_use is specified this option has no effect.

     charon.interfaces_use []
	    A  comma-separated list of network interfaces that should be used by
	    charon. All other interfaces are ignored.

     charon.iptfs
	    Global settings for IP-TFS (RFC 9347).  The  Linux	kernel	supports
	    this  mode	since 6.14. However, it currently only supports aggrega-
	    tion/fragmentation of tunneled IP packets in ESP/AGGFRAG packets. It
	    doesn't yet support other IP-TFS features like sending packets at  a
	    constant rate or congestion control.

     charon.iptfs.accept_fragments [yes]
	    Whether  fragments of inner packets across multiple AGGFRAG payloads
	    are accepted. This is an IKEv2 option, so if the peer doesn't adhere
	    to this request  and  still  sends	such  fragments,  they	will  be
	    processed by the kernel.

     charon.iptfs.dont_frag [no]
	    Force  disabling  fragmenting  inner packets across multiple AGGFRAG
	    payloads when sending outbound traffic (fragmentation  is  automati-
	    cally  disabled  if  the peer indicates that it doesn't support han-
	    dling such packets).

     charon.iptfs.drop_time [1000000]
	    Time in microseconds to wait for out-of-order packets when	process-
	    ing inbound traffic.

     charon.iptfs.init_delay [0]
	    Time in microseconds to wait for subsequent packets to aggregate to-
	    gether  when  sending  outbound traffic. Only relevant if no packets
	    are already queued to be sent.

     charon.iptfs.max_queue_size [1048576]
	    Maximum number of bytes allowed to be queued for sending on the tun-
	    nel (default 1 MiB). If the queue is full, packets are dropped.

     charon.iptfs.packet_size [0]
	    Maximum outer packet size (layer 3) when sending  packets.	The  de-
	    fault  of  0  will use the PMTU as packet size. Note that the kernel
	    currently doesn't pad smaller packets.

     charon.iptfs.reorder_window [3]
	    Number of packets that may arrive out of order when  processing  in-
	    bound traffic.

     charon.keep_alive [20s]
	    NAT keep alive interval.

     charon.keep_alive_dpd_margin [0s]
	    Number  of	seconds the keep alive interval may be exceeded before a
	    DPD is sent instead of a NAT keep alive (0	to  disable).	This  is
	    only  useful  if  a clock is used that includes time spent suspended
	    (e.g. CLOCK_BOOTTIME).

     charon.leak_detective.detailed [yes]
	    Includes source file names and line numbers in leak  detective  out-
	    put.

     charon.leak_detective.usage_threshold [10240]
	    Threshold  in  bytes for allocations to be included in usage reports
	    (0 to include all).

     charon.leak_detective.usage_threshold_count [0]
	    Threshold in number of allocations for allocations to be included in
	    usage reports (0 to include all).

     charon.load []
	    Plugins to load in the IKE daemon charon.

     charon.load_modular [no]
	    If enabled, the list of plugins to load is determined via the  value
	    of	the charon.plugins.<name>.load options.  In addition to a simple
	    boolean flag that option may take an integer  value  indicating  the
	    priority of a plugin, which would influence the order of a plugin in
	    the  plugin  list  (the  default is 1). If two plugins have the same
	    priority their order in the default plugin list  is  preserved.  En-
	    abled  plugins not found in that list are ordered alphabetically be-
	    fore other plugins with the same priority.

     charon.make_before_break [yes]
	    Initiate IKEv2 reauthentication with a make-before-break instead  of
	    a  break-before-make  scheme. Make-before-break uses overlapping IKE
	    and CHILD_SA during reauthentication by first recreating all new SAs
	    before deleting the old ones. This behavior  can  be  beneficial  to
	    avoid  connectivity  gaps during reauthentication, but requires sup-
	    port for overlapping SAs by the peer.  strongSwan  can  handle  such
	    overlapping SAs since version 5.3.0.

     charon.max_ikev1_exchanges [3]
	    Maximum  number  of IKEv1 phase 2 exchanges per IKE_SA to keep state
	    about and track concurrently.

     charon.max_packet [10000]
	    Maximum packet size accepted by charon.

     charon.multiple_authentication [yes]
	    Enable multiple authentication exchanges (RFC 4739).

     charon.nbns1 []
	    WINS servers assigned to peer via configuration payload (CP).

     charon.nbns2 []
	    WINS servers assigned to peer via configuration payload (CP).

     charon.ocsp_nonce_len [32]
	    Length of nonces in OCSP requests. According to RFC 8954, valid val-
	    ues are between 1 and 32, with new clients required to use 32.  Some
	    servers  might  not  support  that	so lowering the value to e.g. 16
	    might be necessary.

     charon.plugins.addrblock.depth [-1]
	    RFC3779 requires that all addrblocks claimed by a  certificate  must
	    be	contained  in the addrblock extension of the issuer certificate,
	    up to the root CA. The default depth setting of -1 enforces this.

	    In practice, third party (root) CAs may not contain  the  extension,
	    making  the addrblock extension unusable under such CAs. By limiting
	    the validation depth, only a certain level	of  issuer  certificates
	    are validated for proper addrblock extensions: A depth of 0 does not
	    check  any	issuer certificate extensions, a depth of 1 only the di-
	    rect issuer of the end entity certificate is checkend, and so on.

     charon.plugins.addrblock.strict [yes]
	    If set to yes, a subject certificate without an addrblock  extension
	    is	rejected  if the issuer certificate has such an addrblock exten-
	    sion. If set to no, subject certificates issued  without  the  addr-
	    block extension are accepted without any traffic selector checks and
	    no policy is enforced by the plugin.

     charon.plugins.android_log.loglevel [1]
	    Loglevel for logging to Android specific logger.

     charon.plugins.attr
	    Section  to specify arbitrary attributes that are assigned to a peer
	    via configuration payload (CP).

     charon.plugins.attr.<attr> []
	    <attr> can be either address,  netmask,  dns,  nbns,  dhcp,  subnet,
	    split-include,  split-exclude  or  the numeric identifier of the at-
	    tribute type. The assigned value can be an IPv4/IPv6 address, a sub-
	    net in CIDR notation or an arbitrary  value  depending  on	the  at-
	    tribute type.  For some attribute types multiple values may be spec-
	    ified as a comma separated list.

     charon.plugins.attr-sql.crash_recovery [yes]
	    Release all online leases during startup.  Disable this to share the
	    DB between multiple VPN gateways.

     charon.plugins.attr-sql.database []
	    Database  URI  for	attr-sql plugin used by charon. If it contains a
	    password, make sure to adjust the permissions of the config file ac-
	    cordingly.

     charon.plugins.attr-sql.lease_history [yes]
	    Enable logging of SQL IP pool leases.

     charon.plugins.botan.internal_rng_only [no]
	    If enabled, only Botan's internal RNG will be  used  throughout  the
	    plugin.  Otherwise, and if supported by Botan, rng_t implementations
	    provided by other loaded plugins will be used as RNG.

     charon.plugins.botan.rng.strong [user-threadsafe]
	    Name  of  the  Botan RNG instance to use for RNG_STRONG and RNG_WEAK
	    quality (e.g.  user, user-threadsafe or system).

     charon.plugins.botan.rng.true [system]
	    Name of the Botan RNG instance to use  for	RNG_TRUE  quality  (e.g.
	    user, user-threadsafe or system).

     charon.plugins.bypass-lan.interfaces_ignore []
	    A  comma-separated	list  of  network interfaces for which connected
	    subnets should be ignored, if interfaces_use is specified  this  op-
	    tion has no effect.

     charon.plugins.bypass-lan.interfaces_use []
	    A  comma-separated	list  of  network interfaces for which connected
	    subnets should be considered. All other interfaces are ignored.

     charon.plugins.certexpire.csv.cron []
	    Cron style string specifying CSV export times.

     charon.plugins.certexpire.csv.empty_string []
	    String to use in empty intermediate CA fields.

     charon.plugins.certexpire.csv.fixed_fields [yes]
	    Use a fixed intermediate CA field count.

     charon.plugins.certexpire.csv.force [yes]
	    Force export of all trustchains we have a private key for.

     charon.plugins.certexpire.csv.format [%d:%m:%Y]
	    strftime(3) format string to export expiration dates as.

     charon.plugins.certexpire.csv.local []
	    strftime(3) format string for the CSV file name to export local cer-
	    tificates to.

     charon.plugins.certexpire.csv.remote []
	    strftime(3) format string for the CSV file	name  to  export  remote
	    certificates to.

     charon.plugins.certexpire.csv.separator [,]
	    CSV field separator.

     charon.plugins.coupling.file []
	    File to store coupling list to.

     charon.plugins.coupling.hash [sha1]
	    Hashing algorithm to fingerprint coupled certificates.

     charon.plugins.coupling.max [1]
	    Maximum number of coupling entries to create.

     charon.plugins.curl.redir [-1]
	    Maximum number of redirects followed by the plugin, set to 0 to dis-
	    able following redirects, set to -1 for no limit.

     charon.plugins.curl.tls_backend []
	    The  SSL/TLS  backend to configure in curl if multiple are available
	    (requires libcurl 7.56 or newer). A list  of  available  options  is
	    logged  on	level 2 if nothing is configured. Similar but on level 1
	    if the selected backend isn't available.

     charon.plugins.dhcp.force_server_address [no]
	    Always use the configured server address. This might be  helpful  if
	    the  DHCP  server  runs on the same host as strongSwan, and the DHCP
	    daemon does not listen on the loopback interface.  In that case  the
	    server  cannot  be	reached via unicast (or even 255.255.255.255) as
	    that would be routed via loopback. Setting this option  to	yes  and
	    configuring  the  local  broadcast	address (e.g.  192.168.0.255) as
	    server address might work.

     charon.plugins.dhcp.identity_lease [no]
	    Derive user-defined MAC address from hash of IKE identity  and  send
	    client identity DHCP option.

     charon.plugins.dhcp.interface []
	    Interface  name  the plugin uses for address allocation. The default
	    is to bind to any (0.0.0.0) and let the system decide which  way  to
	    route the packets to the DHCP server.

     charon.plugins.dhcp.interface_receive [charon.plugins.dhcp.interface]
	    Interface  name  the plugin uses to bind its receive socket. The de-
	    fault is to use the same interface as the send socket. Set it to the
	    empty string to avoid binding the receive socket  to  any  interface
	    while  the	send socket is bound to one. If the   server runs on the
	    same host and the send socket is bound to an interface, it might  be
	    necessary to set this to `lo` or the empty string.

     charon.plugins.dhcp.server [255.255.255.255]
	    DHCP server unicast or broadcast IP address.

     charon.plugins.dhcp.use_server_port [no]
	    Use  the  DHCP  server port (67) as source port, instead of the DHCP
	    client port (68), when a unicast server address  is  configured  and
	    the plugin acts as relay agent.  When replying in this mode the DHCP
	    server  will  always  send packets to the DHCP server port and if no
	    process binds that port an ICMP port unreachables will be sent back,
	    which might be problematic for some DHCP servers.	To  avoid  that,
	    enabling  this  option will cause the plugin to bind the DHCP server
	    port to send its requests when acting as relay agent.  This  is  not
	    necessary  if  a DHCP server is already running on the same host and
	    might even cause conflicts (and since the  server  port  is  already
	    bound, ICMPs should not be an issue).

     charon.plugins.dnscert.enable [no]
	    Enable fetching of CERT RRs via DNS.

     charon.plugins.drbg.max_drbg_requests [4294967294]
	    Number  of	pseudo-random bit requests from the DRBG before an auto-
	    matic reseeding occurs.

     charon.plugins.duplicheck.enable [yes]
	    Enable duplicheck plugin (if loaded).

     charon.plugins.duplicheck.socket [unix://${piddir}/charon.dck]
	    Socket provided by the duplicheck plugin.

     charon.plugins.eap-aka.request_identity [yes]

     charon.plugins.eap-aka-3gpp.seq_check []
	    Enable to activate sequence check of the AKA SQN values in order  to
	    trigger resync cycles.

     charon.plugins.eap-aka-3gpp2.seq_check []
	    Enable  to activate sequence check of the AKA SQN values in order to
	    trigger resync cycles.

     charon.plugins.eap-dynamic.prefer_user [no]
	    If enabled the EAP methods proposed in an EAP-Nak  message	sent  by
	    the peer are preferred over the methods registered locally.

     charon.plugins.eap-dynamic.preferred []
	    The  preferred  EAP  method(s)  to	be used.  If it is not given the
	    first registered method will be used initially.  If  a  comma  sepa-
	    rated  list is given the methods are tried in the given order before
	    trying the rest of the registered methods.

     charon.plugins.eap-gtc.backend [pam]
	    XAuth backend to be used for credential verification.

     charon.plugins.eap-peap.fragment_size [1024]
	    Maximum size of an EAP-PEAP packet.

     charon.plugins.eap-peap.include_length [no]
	    Include length in non-fragmented EAP-PEAP packets.

     charon.plugins.eap-peap.max_message_count [32]
	    Maximum number of processed EAP-PEAP packets (0 = no limit).

     charon.plugins.eap-peap.phase2_method [mschapv2]
	    Phase2 EAP client authentication method.

     charon.plugins.eap-peap.phase2_piggyback [no]
	    Phase2 EAP Identity request piggybacked by server onto TLS	Finished
	    message, relevant only if TLS 1.2 or earlier is negotiated.

     charon.plugins.eap-peap.phase2_tnc [no]
	    Start  phase2  EAP	TNC protocol after successful client authentica-
	    tion.

     charon.plugins.eap-peap.request_peer_auth [no]
	    Request peer authentication based on a client certificate.

     charon.plugins.eap-radius.accounting [no]
	    Send RADIUS accounting information to RADIUS servers.

     charon.plugins.eap-radius.accounting_close_on_timeout [yes]
	    Close the IKE_SA if there is a timeout  during  interim  RADIUS  ac-
	    counting updates.

     charon.plugins.eap-radius.accounting_interval [0s]
	    Interval  in  seconds  for interim RADIUS accounting updates, if not
	    specified by the RADIUS server in the Access-Accept message.

     charon.plugins.eap-radius.accounting_requires_vip [no]
	    If enabled, accounting is disabled unless an IKE_SA has at least one
	    virtual IP.  Only for IKEv2, for IKEv1 a virtual IP is strictly nec-
	    essary.

     charon.plugins.eap-radius.accounting_send_class [no]
	    If enabled, adds the Class attributes received in Access-Accept mes-
	    sage to the RADIUS accounting messages.

     charon.plugins.eap-radius.class_group [no]
	    Use the class attribute sent in the RADIUS-Accept message  as  group
	    membership	information  that is compared to the groups specified in
	    the rightgroups option in ipsec.conf(5).

     charon.plugins.eap-radius.close_all_on_timeout [no]
	    Closes all IKE_SAs if communication with  the  RADIUS  server  times
	    out. If it is not set only the current IKE_SA is closed.

     charon.plugins.eap-radius.dae.enable [no]
	    Enables support for the Dynamic Authorization Extension (RFC 5176).

     charon.plugins.eap-radius.dae.listen [0.0.0.0]
	    Address to listen for DAE messages from the RADIUS server.

     charon.plugins.eap-radius.dae.port [3799]
	    Port to listen for DAE requests.

     charon.plugins.eap-radius.dae.secret []
	    Shared secret used to verify/sign DAE messages. If set, make sure to
	    adjust the permissions of the config file accordingly.

     charon.plugins.eap-radius.eap_start [no]
	    Send EAP-Start instead of EAP-Identity to start RADIUS conversation.

     charon.plugins.eap-radius.filter_id [no]
	    If	the RADIUS tunnel_type attribute with value ESP is received, use
	    the filter_id attribute sent in the RADIUS-Accept message  as  group
	    membership	information  that is compared to the groups specified in
	    the rightgroups option in ipsec.conf(5).

     charon.plugins.eap-radius.forward.ike_to_radius []
	    RADIUS attributes to be forwarded from IKEv2 to RADIUS (can  be  de-
	    fined  by  name  or attribute number, a colon can be used to specify
	    vendor-specific attributes, e.g. Reply-Message, or 11, or 36906:12).

     charon.plugins.eap-radius.forward.radius_to_ike []
	    Same as charon.plugins.eap-radius.forward.ike_to_radius but from RA-
	    DIUS to IKEv2, a strongSwan specific private notify (40969) is  used
	    to transmit the attributes.

     charon.plugins.eap-radius.id_prefix []
	    Prefix to EAP-Identity, some AAA servers use a IMSI prefix to select
	    the EAP method.

     charon.plugins.eap-radius.nas_identifier [strongSwan]
	    NAS-Identifier to include in RADIUS messages.

     charon.plugins.eap-radius.port [1812]
	    Port of RADIUS server (authentication).

     charon.plugins.eap-radius.retransmit_base [1.4]
	    Base to use for calculating exponential back off.

     charon.plugins.eap-radius.retransmit_timeout [2.0]
	    Timeout in seconds before sending first retransmit.

     charon.plugins.eap-radius.retransmit_tries [4]
	    Number of times to retransmit a packet before giving up.

     charon.plugins.eap-radius.secret []
	    Shared  secret  between  RADIUS and NAS. If set, make sure to adjust
	    the permissions of the config file accordingly.

     charon.plugins.eap-radius.server []
	    IP/Hostname of RADIUS server.

     charon.plugins.eap-radius.servers
	    Section to specify multiple RADIUS servers. The source,  nas_identi-
	    fier,  secret, sockets and port (or auth_port) options can be speci-
	    fied for each server. A server's IP/Hostname can be configured using
	    the address option. The acct_port [1813] option can be used to spec-
	    ify the port used for RADIUS accounting. For each  RADIUS  server  a
	    priority  can  be specified using the preference [0] option. The re-
	    transmission time for each server can set set using retransmit_base,
	    retransmit_timeout and retransmit_tries.

     charon.plugins.eap-radius.sockets [1]
	    Number of sockets (ports) to use, increase for high load.

     charon.plugins.eap-radius.source []
	    Optional specific source IP to use.

     charon.plugins.eap-radius.station_id_with_port [yes]
	    Whether to include the UDP port  in  the  Called-  and  Calling-Sta-
	    tion-Id RADIUS attributes.

     charon.plugins.eap-radius.xauth
	    Section  to  configure  multiple XAuth authentication rounds via RA-
	    DIUS. The subsections define so called authentication profiles  with
	    arbitrary names. In each profile section one or more XAuth types can
	    be	configured,  with  an assigned message. For each type a separate
	    XAuth exchange will be initiated and all  replies  get  concatenated
	    into  the User-Password attribute, which then gets verified over RA-
	    DIUS.

	    Available XAuth types are password, passcode, nextpin,  and  answer.
	    This  type	is not relevant to strongSwan or the AAA server, but the
	    client may show a different dialog (along with the	configured  mes-
	    sage).

	    To	use  the  configured profiles, they have to be configured in the
	    respective connection in  ipsec.conf(5)  by  appending  the  profile
	    name,  separated by a colon, to the xauth-radius XAauth backend con-
	    figuration	in  rightauth  or  rightauth2,	 for   instance,   righ-
	    tauth2=xauth-radius:profile.

     charon.plugins.eap-sim.request_identity [yes]

     charon.plugins.eap-simaka-sql.database []

     charon.plugins.eap-simaka-sql.remove_used [no]

     charon.plugins.eap-tls.fragment_size [1024]
	    Maximum size of an EAP-TLS packet.

     charon.plugins.eap-tls.include_length [yes]
	    Include length in non-fragmented EAP-TLS packets.

     charon.plugins.eap-tls.max_message_count [32]
	    Maximum number of processed EAP-TLS packets (0 = no limit).

     charon.plugins.eap-tnc.max_message_count [10]
	    Maximum number of processed EAP-TNC packets (0 = no limit).

     charon.plugins.eap-tnc.protocol [tnccs-2.0]
	    IF-TNCCS   protocol   version  to  be  used  (tnccs-1.1,  tnccs-2.0,
	    tnccs-dynamic).

     charon.plugins.eap-ttls.fragment_size [1024]
	    Maximum size of an EAP-TTLS packet.

     charon.plugins.eap-ttls.include_length [yes]
	    Include length in non-fragmented EAP-TTLS packets.

     charon.plugins.eap-ttls.max_message_count [32]
	    Maximum number of processed EAP-TTLS packets (0 = no limit).

     charon.plugins.eap-ttls.phase2_method [md5]
	    Phase2 EAP client authentication method.

     charon.plugins.eap-ttls.phase2_piggyback [no]
	    Phase2 EAP Identity request piggybacked by server onto TLS	Finished
	    message.

     charon.plugins.eap-ttls.phase2_tnc [no]
	    Start  phase2  EAP	TNC protocol after successful client authentica-
	    tion.

     charon.plugins.eap-ttls.phase2_tnc_method [pt]
	    Phase2 EAP TNC transport protocol (pt as  IETF  standard  or  legacy
	    tnc)

     charon.plugins.eap-ttls.request_peer_auth [no]
	    Request peer authentication based on a client certificate.

     charon.plugins.error-notify.socket [unix://${piddir}/charon.enfy]
	    Socket provided by the error-notify plugin.

     charon.plugins.ext-auth.script []
	    Command  to  pass to the system shell for peer authorization. Autho-
	    rization is considered successful if the command  executes	normally
	    with  an  exit  code of zero. For all other exit codes IKE_SA autho-
	    rization is rejected.

	    The following  environment	variables  get	passed	to  the  script:
	    IKE_UNIQUE_ID:  The  IKE_SA  numerical unique identifier.  IKE_NAME:
	    The peer configuration connection name.  IKE_LOCAL_HOST:  Local  IKE
	    IP	address.  IKE_REMOTE_HOST: Remote IKE IP address.  IKE_LOCAL_ID:
	    Local IKE identity.  IKE_REMOTE_ID: Remote	IKE  identity.	 IKE_RE-
	    MOTE_EAP_ID: Remote EAP or XAuth identity, if used.

     charon.plugins.forecast.groups
     [224.0.0.1,224.0.0.22,224.0.0.251,224.0.0.252,239.255.255.250]
	    Comma  separated list of multicast groups to join locally. The local
	    host receives and forwards packets in the local LAN for joined  mul-
	    ticast  groups  only.  Packets matching the list of multicast groups
	    get forwarded to connected clients. The default group includes  host
	    multicasts,  IGMP, mDNS, LLMNR and SSDP/WS-Discovery, and is usually
	    a good choice for Windows clients.

     charon.plugins.forecast.interface []
	    Name of the local interface to listen  for	broadcasts  messages  to
	    forward.  If  no interface is configured, the first usable interface
	    is used, which is usually just fine for single-homed hosts. If  your
	    host  has  multiple interfaces, set this option to the local LAN in-
	    terface you want to forward broadcasts from/to.

     charon.plugins.forecast.reinject []
	    Comma separated list of CHILD_SA configuration names  for  which  to
	    perform  multi/broadcast  reinjection.  For  clients connecting over
	    such a configuration, any multi/broadcast received over  the  tunnel
	    gets  reinjected  to  all  active tunnels. This makes the broadcasts
	    visible to other peers, and for examples allows clients to see  oth-
	    ers  shares.  If  disabled, multi/broadcast messages received over a
	    tunnel are injected to the local network  only,  but  not  to  other
	    IPsec clients.

     charon.plugins.gcrypt.quick_random [no]
	    Use faster random numbers in gcrypt; for testing only, produces weak
	    keys!

     charon.plugins.ha.autobalance [0]
	    Interval  in  seconds  to automatically balance handled segments be-
	    tween nodes. Set to 0 to disable.

     charon.plugins.ha.buflen [2048]
	    Buffer size for received HA messages. For IKEv1 the public	DH  fac-
	    tors  are  also transmitted so depending on the DH group the HA mes-
	    sages can get quite big (the default should be fine up to modp4096).

     charon.plugins.ha.fifo_interface [yes]

     charon.plugins.ha.heartbeat_delay [1000]

     charon.plugins.ha.heartbeat_timeout [2100]

     charon.plugins.ha.local []

     charon.plugins.ha.monitor [yes]

     charon.plugins.ha.pools []

     charon.plugins.ha.remote []

     charon.plugins.ha.resync [yes]

     charon.plugins.ha.secret []

     charon.plugins.ha.segment_count [1]

     charon.plugins.ipseckey.enable [no]
	    Enable fetching of IPSECKEY RRs via DNS.

     charon.plugins.kernel-libipsec.allow_peer_ts [no]
	    Allow that the remote traffic selector  equals  the  IKE  peer.  The
	    route  installed  for such traffic (via TUN device) usually prevents
	    further IKE traffic. The fwmark options for the  kernel-netlink  and
	    socket-default plugins can be used to circumvent that problem.

     charon.plugins.kernel-libipsec.fwmark [charon.plugins.socket-default.fw-
     mark]
	    Firewall mark to set on outbound raw ESP packets.

     charon.plugins.kernel-libipsec.raw_esp [no]
	    Whether to send and receive ESP packets without UDP encapsulation if
	    supported on this platform and no NAT is detected.

     charon.plugins.kernel-netlink.buflen [<min(PAGE_SIZE, 8192)>]
	    Buffer size for received Netlink messages.

     charon.plugins.kernel-netlink.fwmark []
	    Firewall mark to set on the routing rule that directs traffic to our
	    routing  table. The format is [!]mark[/mask], where the optional ex-
	    clamation mark inverts the meaning (i.e. the rule  only  applies  to
	    packets that don't match the mark).

     charon.plugins.kernel-netlink.hw_offload_feature_interface [lo]
	    If the kernel supports hardware offloading, the plugin needs to find
	    the  feature  flag	which represents hardware offloading support for
	    network devices. Using the loopback device for this purpose is  usu-
	    ally  fine,  since	it  should  always be present. For rare cases in
	    which the loopback device cannot be used to obtain	the  appropriate
	    feature  flag, this option can be used to specify an alternative in-
	    terface for offload feature detection.

     charon.plugins.kernel-netlink.ignore_retransmit_errors [no]
	    Whether to ignore errors potentially resulting  from  a  retransmis-
	    sion.

     charon.plugins.kernel-netlink.install_routes_xfrmi [no]
	    Whether  routes  via XFRM interfaces are automatically installed for
	    SAs that reference such an interface via if_id_out.  If the  traffic
	    selectors include the IKE traffic to the peer, this requires special
	    care  (e.g.  installing  bypass policies and/or routes, or setting a
	    mark on the IKE socket and excluding such packets from  the  config-
	    ured routing table via fwmark option).

     charon.plugins.kernel-netlink.mss [0]
	    MSS to set on installed routes, 0 to disable.

     charon.plugins.kernel-netlink.mtu [0]
	    MTU to set on installed routes, 0 to disable.

     charon.plugins.kernel-netlink.parallel_route [no]
	    Whether  to  perform  concurrent  Netlink  ROUTE queries on a single
	    socket. While parallel queries can improve throughput, it  has  more
	    overhead. On vanilla Linux, DUMP queries fail with EBUSY and must be
	    retried, further decreasing performance.

     charon.plugins.kernel-netlink.parallel_xfrm [no]
	    Whether  to  perform  concurrent  Netlink  XFRM  queries on a single
	    socket.

     charon.plugins.kernel-netlink.policy_update [no]
	    Whether to always use XFRM_MSG_UPDPOLICY to install policies.

     charon.plugins.kernel-netlink.port_bypass [no]
	    Whether to use port or socket based IKE XFRM  bypass  policies.  IKE
	    bypass policies are used to exempt IKE traffic from XFRM processing.
	    The  default  socket based policies are directly tied to the IKE UDP
	    sockets, port based policies use global XFRM bypass policies for the
	    used IKE UDP ports.

     charon.plugins.kernel-netlink.process_rules [no]
	    Whether to process changes in routing rules to trigger roam  events.
	    This  is  currently  only useful if the kernel based route lookup is
	    used (i.e. if route installation is disabled or an	inverted  fwmark
	    match is configured).

     charon.plugins.kernel-netlink.receive_buffer_size [8388608]
	    Maximum  Netlink socket receive buffer in bytes. This value controls
	    how many bytes of Netlink  messages  can  be  queued  to  a  Netlink
	    socket.  If  set  to 0, the default from /proc/sys/net/core/rmem_de-
	    fault will apply. Note that the kernel doubles the configured  value
	    to	account  for  overhead.  To  exceed the system-wide maximum from
	    /proc/sys/net/core/rmem_max, special privileges (CAP_NET_ADMIN)  are
	    necessary, otherwise, the kernel silently caps the value.

     charon.plugins.kernel-netlink.retries [0]
	    Number of Netlink message retransmissions to send on timeout.

     charon.plugins.kernel-netlink.roam_events [yes]
	    Whether  to trigger roam events when interfaces, addresses or routes
	    change.

     charon.plugins.kernel-netlink.set_proto_port_transport_sa [no]
	    Whether to set protocol and  ports	in  the  selector  installed  on
	    transport  mode  IPsec  SAs  in  the kernel. While doing so enforces
	    policies for inbound traffic, it also prevents the use of  a  single
	    IPsec SA by more than one traffic selector.

     charon.plugins.kernel-netlink.spdh_thresh
	    XFRM policy hashing threshold configuration for IPv4 and IPv6.

	    The  section  defines  hashing thresholds to configure in the kernel
	    during daemon startup. Each address family takes a threshold for the
	    local subnet of an IPsec policy (src in out-policies, dst in in- and
	    forward-policies) and the remote subnet (dst in out-policies, src in
	    in- and forward-policies).

	    If the subnet has more or equal net bits  than  the  threshold,  the
	    first threshold bits are used to calculate a hash to lookup the pol-
	    icy.

	    Policy  hashing  thresholds  are not supported before Linux 3.18 and
	    might conflict with socket policies before Linux 4.8.

     charon.plugins.kernel-netlink.spdh_thresh.ipv4.lbits [32]
	    Local subnet XFRM policy hashing threshold for IPv4.

     charon.plugins.kernel-netlink.spdh_thresh.ipv4.rbits [32]
	    Remote subnet XFRM policy hashing threshold for IPv4.

     charon.plugins.kernel-netlink.spdh_thresh.ipv6.lbits [128]
	    Local subnet XFRM policy hashing threshold for IPv6.

     charon.plugins.kernel-netlink.spdh_thresh.ipv6.rbits [128]
	    Remote subnet XFRM policy hashing threshold for IPv6.

     charon.plugins.kernel-netlink.timeout [0]
	    Netlink message retransmission timeout,  0	to  disable  retransmis-
	    sions.

     charon.plugins.kernel-netlink.xfrm_acq_expires [165]
	    Lifetime  of  XFRM	acquire state created by the kernel when traffic
	    matches   a   trap	 policy.   The	  value    gets    written    to
	    /proc/sys/net/core/xfrm_acq_expires.   Indirectly controls the delay
	    between XFRM acquire messages triggered by the  kernel  for  a  trap
	    policy.  The same value is used as timeout for SPIs allocated by the
	    kernel. The default value equals the total	 retransmission  timeout
	    for IKE messages, see IKEv2 RETRANSMISSION in strongswan.conf(5).

     charon.plugins.kernel-pfkey.events_buffer_size [0]
	    Size  of  the  receive  buffer  for  the event socket (0 for default
	    size). Because events are received	asynchronously	installing  e.g.
	    lots  of  policies	may  require a larger buffer than the default on
	    certain platforms in order to receive all messages.

     charon.plugins.kernel-pfkey.route_via_internal [no]
	    Whether to use the	internal  or  external	interface  in  installed
	    routes.  The internal interface is the one where the IP address con-
	    tained in the local traffic selector is located, the external inter-
	    face is the one over which the destination address of the IPsec tun-
	    nel can be reached. This is not relevant if virtual  IPs  are  used,
	    for which a TUN device is created that's used in the routes.

     charon.plugins.kernel-pfroute.mtu [1400]
	    MTU to set on TUN devices created for virtual IPs.

     charon.plugins.kernel-pfroute.vip_wait [1000]
	    Time  in  ms to wait until virtual IP addresses appear/disappear be-
	    fore failing.

     charon.plugins.led.activity_led []

     charon.plugins.led.blink_time [50]

     charon.plugins.load-tester
	    Section to configure the  load-tester  plugin,  see  LOAD  TESTS  in
	    strongswan.conf(5) for details.

     charon.plugins.load-tester.addrs
	    Section  that  contains  key/value pairs with address pools (in CIDR
	    notation) to use for  a  specific  network	interface  e.g.  eth0  =
	    10.10.0.0/16.

     charon.plugins.load-tester.addrs_keep [no]
	    Whether  to  keep dynamic addresses even after the associated SA got
	    terminated.

     charon.plugins.load-tester.addrs_prefix [16]
	    Network prefix length to use when installing dynamic  addresses.  If
	    set to -1 the full address is used (i.e. 32 or 128).

     charon.plugins.load-tester.ca_dir []
	    Directory to load (intermediate) CA certificates from.

     charon.plugins.load-tester.child_rekey [600]
	    Seconds to start CHILD_SA rekeying after setup.

     charon.plugins.load-tester.crl []
	    URI  to a CRL to include as certificate distribution point in gener-
	    ated certificates.

     charon.plugins.load-tester.delay [0]
	    Delay between initiations for each thread.

     charon.plugins.load-tester.delete_after_established [no]
	    Delete an IKE_SA as soon as it has been established.

     charon.plugins.load-tester.digest [sha1]
	    Digest algorithm used when issuing certificates.

     charon.plugins.load-tester.dpd_delay [0]
	    DPD delay to use in load test.

     charon.plugins.load-tester.dynamic_port [0]
	    Base port to be used for requests  (each  client  uses  a  different
	    port).

     charon.plugins.load-tester.eap_password [default-pwd]
	    EAP secret to use in load test.

     charon.plugins.load-tester.enable [no]
	    Enable  the  load testing plugin.  WARNING: Never enable this plugin
	    on productive systems. It provides preconfigured credentials and al-
	    lows an attacker to authenticate as any user.

     charon.plugins.load-tester.esp [aes128-sha1]
	    CHILD_SA proposal to use for load tests.

     charon.plugins.load-tester.fake_kernel [no]
	    Fake the kernel interface to allow load-testing against self.

     charon.plugins.load-tester.ike_rekey [0]
	    Seconds to start IKE_SA rekeying after setup.

     charon.plugins.load-tester.init_limit [0]
	    Global limit of concurrently established SAs during load test.

     charon.plugins.load-tester.initiator [0.0.0.0]
	    Address to initiate from.

     charon.plugins.load-tester.initiator_auth [pubkey]
	    Authentication method(s) the initiator uses.

     charon.plugins.load-tester.initiator_id []
	    Initiator ID used in load test.

     charon.plugins.load-tester.initiator_match []
	    Initiator ID to match against as responder.

     charon.plugins.load-tester.initiator_tsi []
	    Traffic selector on initiator side, as proposed by initiator.

     charon.plugins.load-tester.initiator_tsr []
	    Traffic selector on responder side, as proposed by initiator.

     charon.plugins.load-tester.initiators [0]
	    Number of concurrent initiator threads to use in load test.

     charon.plugins.load-tester.issuer_cert []
	    Path to the issuer certificate (if not configured a  hard-coded  de-
	    fault value is used).

     charon.plugins.load-tester.issuer_key []
	    Path  to private key that is used to issue certificates (if not con-
	    figured a hard-coded default value is used).

     charon.plugins.load-tester.iterations [1]
	    Number of IKE_SAs to initiate by each initiator in load test.

     charon.plugins.load-tester.mode [tunnel]
	    IPsec mode to use, one of tunnel, transport, or beet.

     charon.plugins.load-tester.pool []
	    Provide INTERNAL_IPV4_ADDRs from a named pool.

     charon.plugins.load-tester.preshared_key [<default-psk>]
	    Preshared key to use in load test.

     charon.plugins.load-tester.proposal [aes128-sha1-modp768]
	    IKE proposal to use in load test.

     charon.plugins.load-tester.request_virtual_ip [no]
	    Request  an  INTERNAL_IPV4_ADDR  and  INTERNAL_IPV6_ADDR  from   the
	    server.

     charon.plugins.load-tester.responder [127.0.0.1]
	    Address to initiation connections to.

     charon.plugins.load-tester.responder_auth [pubkey]
	    Authentication method(s) the responder uses.

     charon.plugins.load-tester.responder_id []
	    Responder ID used in load test.

     charon.plugins.load-tester.responder_tsi [initiator_tsi]
	    Traffic selector on initiator side, as narrowed by responder.

     charon.plugins.load-tester.responder_tsr [initiator_tsr]
	    Traffic selector on responder side, as narrowed by responder.

     charon.plugins.load-tester.shutdown_when_complete [no]
	    Shutdown the daemon after all IKE_SAs have been established.

     charon.plugins.load-tester.socket [unix://${piddir}/charon.ldt]
	    Socket provided by the load-tester plugin.

     charon.plugins.load-tester.version [0]
	    IKE  version  to  use (0 means use IKEv2 as initiator and accept any
	    version as responder).

     charon.plugins.lookip.socket [unix://${piddir}/charon.lkp]
	    Socket provided by the lookip plugin.

     charon.plugins.openssl.engine_id [pkcs11]
	    ENGINE ID to use in the OpenSSL plugin.

     charon.plugins.openssl.fips_mode [0]
	    Set OpenSSL FIPS mode.  With OpenSSL before 3.0, the supported  val-
	    ues  are  disabled(0),  enabled(1)	and  Suite  B  enabled(2).  With
	    OpenSSL 3+, any value other than 0 will explicitly load the fips and
	    base providers (load_legacy will be ignored). The latter  still  re-
	    quires  the  config  in fipsmodule.cnf (e.g.  for the module's MAC),
	    but allows explicitly loading the provider if it's not activated  in
	    that config.

     charon.plugins.openssl.load_legacy [yes]
	    Load the legacy provider in OpenSSL 3+ for algorithms like MD4, DES,
	    or	Blowfish  (the first two are required for EAP-MSCHAPv2). If dis-
	    abled, the default provider is loaded, or those  configured  in  the
	    OpenSSL config (e.g. the fips provider).

     charon.plugins.openxpki.database []
	    Database  URI connecting to the OpenXPKI certificate database. If it
	    contains a password, make sure to adjust the permissions of the con-
	    fig file accordingly.

     charon.plugins.osx-attr.append [yes]
	    Whether DNS servers are appended to existing entries, instead of re-
	    placing them.

     charon.plugins.p-cscf.enable
	    Section to enable requesting P-CSCF server addresses for  individual
	    connections.

     charon.plugins.p-cscf.enable.<conn> [no]
	    <conn>  is	the  name of a connection with an ePDG from which to re-
	    quest P-CSCF server addresses.  Requests will be sent for  addresses
	    of the same families for which internal IPs are requested.

     charon.plugins.pkcs11.modules
	    List of available PKCS#11 modules.

     charon.plugins.pkcs11.modules.<name>.load_certs [yes]
	    Whether to automatically load certificates from tokens.

     charon.plugins.pkcs11.modules.<name>.os_locking [no]
	    Whether OS locking should be enabled for this module.

     charon.plugins.pkcs11.modules.<name>.path []
	    Full path to the shared object file of this PKCS#11 module.

     charon.plugins.pkcs11.reload_certs [no]
	    Reload certificates from all tokens if charon receives a SIGHUP.

     charon.plugins.pkcs11.use_dh [no]
	    Whether  the  PKCS#11  modules  should  be used for DH and ECDH (see
	    use_ecc option).

     charon.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.

     charon.plugins.pkcs11.use_hasher [no]
	    Whether the PKCS#11 modules should be used to hash data.

     charon.plugins.pkcs11.use_pubkey [no]
	    Whether  the  PKCS#11  modules  should be used for public key opera-
	    tions, even for keys not stored on tokens.

     charon.plugins.pkcs11.use_rng [no]
	    Whether the PKCS#11 modules should be used as RNG.

     charon.plugins.pkcs11.use_rsa_pss_hashers [no]
	    Whether the PKCS#11 modules should try to use internal  hashing  for
	    RSA-PSS  signatures (some PKCS#11 libraries don't implement internal
	    hashing in conjunction with RSA-PSS correctly).

     charon.plugins.radattr.dir []
	    Directory where RADIUS attributes are stored in  client-ID	specific
	    files.

     charon.plugins.radattr.message_id [-1]
	    Attributes	are  added  to all IKE_AUTH messages by default (-1), or
	    only to the IKE_AUTH message with the given IKEv2 message ID.

     charon.plugins.random.random [${random_device}]
	    File to read random bytes from.

     charon.plugins.random.strong_equals_true [no]
	    If set to yes the RNG_STRONG class reads random bytes from the  same
	    source as the RNG_TRUE class.

     charon.plugins.random.urandom [${urandom_device}]
	    File to read pseudo random bytes from.

     charon.plugins.resolve.file [/etc/resolv.conf]
	    File where to add DNS server entries if not using resolvconf(8).

     charon.plugins.resolve.resolvconf.iface [lo.ipsec]
	    The  interface name and protocol sent to resolvconf(8).  This has to
	    be a valid interface name according to the rules defined by  resolv-
	    conf.   Also,  it should have a high priority according to the order
	    defined in interface-order(5) if relevant on the system.

     charon.plugins.resolve.resolvconf.path [/sbin/resolvconf]
	    Path/command for resolvconf(8).  The command is executed by a shell,
	    so "resolvconf" will work if it's in $PATH of the daemon.

	    If not configured, resolvconf(8) will be used if found  at	the  de-
	    fault  location.  Otherwise, the file in charon.plugins.resolve.file
	    will be modified directly.

     charon.plugins.revocation.enable_crl [yes]
	    Whether CRL validation should be enabled.

     charon.plugins.revocation.enable_ocsp [yes]
	    Whether OCSP validation should be enabled.

     charon.plugins.revocation.timeout [10s]
	    Timeout used when fetching OCSP/CRL.

     charon.plugins.save-keys.esp [no]
	    Whether to save ESP keys.

     charon.plugins.save-keys.ike [no]
	    Whether to save IKE keys.

     charon.plugins.save-keys.load [no]
	    Whether to load the plugin.

     charon.plugins.save-keys.wireshark_keys []
	    Directory where the keys are stored in the format supported by Wire-
	    shark. IKEv1 keys are stored  in  the  ikev1_decryption_table  file.
	    IKEv2  keys  are stored in the ikev2_decryption_table file. Keys for
	    ESP CHILD_SAs are stored in the esp_sa file.

     charon.plugins.socket-default.fwmark []
	    Firewall mark to set on outbound packets.

     charon.plugins.socket-default.set_source [yes]
	    Set source address on outbound packets, if possible.

     charon.plugins.socket-default.set_sourceif [no]
	    Force sending interface on outbound packets, if possible.  This  al-
	    lows using IPv6 link-local addresses as tunnel endpoints.

     charon.plugins.socket-default.use_ipv4 [yes]
	    Listen on IPv4, if possible.

     charon.plugins.socket-default.use_ipv6 [yes]
	    Listen on IPv6, if possible.

     charon.plugins.sql.database []
	    Database  URI  for	charon's  SQL plugin. If it contains a password,
	    make sure to adjust the permissions of the config file accordingly.

     charon.plugins.sql.loglevel [-1]
	    Loglevel for logging to SQL database.

     charon.plugins.stroke.allow_swap [yes]
	    Analyze addresses/hostnames in left|right to detect  which	side  is
	    local  and swap configuration options if necessary. If disabled left
	    is always local.

     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.

     charon.plugins.stroke.max_concurrent [4]
	    Maximum number of stroke messages handled concurrently.

     charon.plugins.stroke.prevent_loglevel_changes [no]
	    If enabled log level changes via stroke socket are not allowed.

     charon.plugins.stroke.secrets_file [${sysconfdir}/ipsec.secrets]
	    Location of the ipsec.secrets file

     charon.plugins.stroke.socket [unix://${piddir}/charon.ctl]
	    Socket provided by the stroke plugin.

     charon.plugins.stroke.timeout [0]
	    Timeout in ms for any stroke command. Use 0 to disable the timeout.

     charon.plugins.systime-fix.interval [0]
	    Interval  in  seconds  to check system time for validity. 0 disables
	    the check.

     charon.plugins.systime-fix.reauth [no]
	    Whether to use reauth or delete if an invalid cert lifetime  is  de-
	    tected.

     charon.plugins.systime-fix.threshold []
	    Threshold  date  where  system time is considered valid. Disabled if
	    not specified.

     charon.plugins.systime-fix.threshold_format [%Y]
	    strptime(3) format used to parse threshold option.

     charon.plugins.systime-fix.timeout [0s]
	    How long to wait for a valid system time if an interval  is  config-
	    ured. 0 to recheck indefinitely.

     charon.plugins.tnc-ifmap.client_cert []
	    Path to X.509 certificate file of IF-MAP client.

     charon.plugins.tnc-ifmap.client_key []
	    Path to private key file of IF-MAP client.

     charon.plugins.tnc-ifmap.device_name []
	    Unique name of strongSwan server as a PEP and/or PDP device.

     charon.plugins.tnc-ifmap.renew_session_interval [150]
	    Interval in seconds between periodic IF-MAP RenewSession requests.

     charon.plugins.tnc-ifmap.server_cert []
	    Path to X.509 certificate file of IF-MAP server.

     charon.plugins.tnc-ifmap.server_uri [https://localhost:8444/imap]
	    URI of the form [https://]servername[:port][/path].

     charon.plugins.tnc-ifmap.username_password []
	    Credentials  of IF-MAP client of the form username:password. If set,
	    make sure to adjust the permissions of the config file accordingly.

     charon.plugins.tnc-imc.dlclose [yes]
	    Unload IMC after use.

     charon.plugins.tnc-imc.preferred_language [en]
	    Preferred language for TNC recommendations.

     charon.plugins.tnc-imv.dlclose [yes]
	    Unload IMV after use.

     charon.plugins.tnc-imv.recommendation_policy [default]
	    TNC recommendation policy, one of default, any, or all.

     charon.plugins.tnc-pdp.pt_tls.enable [yes]
	    Enable PT-TLS protocol on the strongSwan PDP.

     charon.plugins.tnc-pdp.pt_tls.port [271]
	    PT-TLS server port the strongSwan PDP is listening on.

     charon.plugins.tnc-pdp.radius.enable [yes]
	    Enable RADIUS protocol on the strongSwan PDP.

     charon.plugins.tnc-pdp.radius.method [ttls]
	    EAP tunnel method to be used.

     charon.plugins.tnc-pdp.radius.port [1812]
	    RADIUS server port the strongSwan PDP is listening on.

     charon.plugins.tnc-pdp.radius.secret []
	    Shared RADIUS secret between strongSwan PDP and NAS.  If  set,  make
	    sure to adjust the permissions of the config file accordingly.

     charon.plugins.tnc-pdp.server []
	    Name of the strongSwan PDP as contained in the AAA certificate.

     charon.plugins.tnc-pdp.timeout []
	    Timeout in seconds before closing incomplete connections.

     charon.plugins.tnccs-11.max_message_size [45000]
	    Maximum size of a PA-TNC message (XML & Base64 encoding).

     charon.plugins.tnccs-20.max_batch_size [65522]
	    Maximum size of a PB-TNC batch (upper limit via PT-EAP = 65529).

     charon.plugins.tnccs-20.max_message_size [65490]
	    Maximum size of a PA-TNC message (upper limit via PT-EAP = 65497).

     charon.plugins.tnccs-20.mutual [no]
	    Enable PB-TNC mutual protocol.

     charon.plugins.tnccs-20.tests.pb_tnc_noskip [no]
	    Send an unsupported PB-TNC message type with the NOSKIP flag set.

     charon.plugins.tnccs-20.tests.pb_tnc_version [2]
	    Send a PB-TNC batch with a modified PB-TNC version.

     charon.plugins.tpm.ek_handle []
	    Handle  of	the RSA or ECC Endorsement Key (EK) to be used to set up
	    an authenticated session with a TPM 2.0 (e.g. 0x81010001).

     charon.plugins.tpm.fips_186_4 [no]
	    Is the TPM 2.0 FIPS-186-4 compliant, forcing e.g. the use of the de-
	    fault salt	length	instead  of  maximum  salt  length  with  RSAPSS
	    padding.

     charon.plugins.tpm.tcti.name [device|tabrmd]
	    Name of TPM 2.0 TCTI library. Valid values: tabrmd, device or mssim.
	    Defaults  are  device  if the /dev/tpmrm0 in-kernel TPM 2.0 resource
	    manager device exists, and tabrmd  otherwise,  requiring  the  d-bus
	    based TPM 2.0 access broker and resource manager to be available.

     charon.plugins.tpm.tcti.opts [/dev/tpmrm0|<none>]
	    Options  for  the  TPM 2.0 TCTI library. Defaults are /dev/tpmrm0 if
	    the TCTI library name is device and no options otherwise.

     charon.plugins.tpm.use_rng [no]
	    Whether the TPM should be used as RNG. For security  reasons  enable
	    only  if  an  authenticated session can be set up (see ek_handle op-
	    tion).

     charon.plugins.unbound.dlv_anchors []
	    File to read trusted keys  for  DLV  (DNSSEC  Lookaside  Validation)
	    from. It uses the same format as trust_anchors.  Only one DLV can be
	    configured,  which	is  then  used as a root trusted DLV, this means
	    that it is a lookaside for the root.

     charon.plugins.unbound.resolv_conf [/etc/resolv.conf]
	    File to read DNS resolver configuration from.

     charon.plugins.unbound.trust_anchors [${sysconfdir}/ipsec.d/dnssec.keys]
	    File to read DNSSEC trust anchors from (usually root zone KSK).  The
	    format of the file is the standard DNS Zone file format, anchors can
	    be stored as DS or DNSKEY entries in the file.

     charon.plugins.updown.dns_handler [no]
	    Whether  the  updown  script  should handle DNS servers assigned via
	    IKEv1 Mode Config or IKEv2 Config Payloads (if enabled they can't be
	    handled by other plugins, like resolve)

     charon.plugins.vici.socket [unix://${piddir}/charon.vici]
	    Socket the vici plugin serves clients.

     charon.plugins.whitelist.enable [yes]
	    Enable loaded whitelist plugin.

     charon.plugins.whitelist.socket [unix://${piddir}/charon.wlst]
	    Socket provided by the whitelist plugin.

     charon.plugins.wolfssl.fips_mode [no]
	    Enable to prevent loading the plugin if wolfSSL is not in FIPS mode.

     charon.plugins.xauth-eap.backend [radius]
	    EAP plugin to be used as backend for XAuth credential verification.

     charon.plugins.xauth-pam.pam_service [login]
	    PAM service to be used for authentication.

     charon.plugins.xauth-pam.session [no]
	    Open/close a PAM session for each active IKE_SA.

     charon.plugins.xauth-pam.trim_email [yes]
	    If an email address is received as an XAuth  username,  trim  it  to
	    just the username part.

     charon.port [500]
	    UDP port used locally. If set to 0 a random port will be allocated.

     charon.port_nat_t [4500]
	    UDP  port  used  locally in case of NAT-T. If set to 0 a random port
	    will be allocated.	Has to be different from charon.port,  otherwise
	    a random port will be allocated.

     charon.prefer_best_path [no]
	    By	default,  charon keeps SAs on the routing path with addresses it
	    previously used if that path is still usable. By setting this option
	    to yes, it tries more aggressively to  update  SAs	with  MOBIKE  on
	    routing  priority  changes	using  the cheapest path. This adds more
	    noise, but allows to  dynamically  adapt  SAs  to  routing	priority
	    changes.  This  option  has  no effect if MOBIKE is not supported or
	    disabled.

     charon.prefer_configured_proposals [yes]
	    Prefer locally configured proposals for IKE/IPsec over supplied ones
	    as responder (disabling this can avoid keying  retries  due  to  IN-
	    VALID_KE_PAYLOAD notifies).

     charon.prefer_temporary_addrs [no]
	    By	default, permanent IPv6 source addresses are preferred over tem-
	    porary ones (RFC 4941), to make connections more stable. Enable this
	    option to reverse this.

	    It also affects which IPv6 addresses are announced as additional ad-
	    dresses if MOBIKE is used.	If the option is disabled,  only  perma-
	    nent addresses are sent, and only temporary ones if it is enabled.

     charon.process_route [yes]
	    Process RTM_NEWROUTE and RTM_DELROUTE events.

     charon.processor.priority_threads
	    Section  to  configure  the  number of reserved threads per priority
	    class see JOB PRIORITY MANAGEMENT in strongswan.conf(5).

     charon.rdn_matching [strict]
	    How RDNs in subject DNs of certificates are matched against  config-
	    ured  identities.  Possible  values  are  strict  (the default), re-
	    ordered, and relaxed.  With strict the number, type and order of all
	    RDNs has to match, wildcards (*) for the values of RDNs are  allowed
	    (that's  the  case	for  all  three  variants). Using reordered also
	    matches DNs if the RDNs appear in a different order, the number  and
	    type still has to match. Finally, relaxed also allows matches of DNs
	    that  contain  more  RDNs than the configured identity (missing RDNs
	    are treated like a wildcard match).

	    Note that reordered and relaxed impose a  considerable  overhead  on
	    memory usage and runtime, in particular, for mismatches, compared to
	    strict.

     charon.receive_delay [0]
	    Delay in ms for receiving packets, to simulate larger RTT.

     charon.receive_delay_request [yes]
	    Delay request messages.

     charon.receive_delay_response [yes]
	    Delay response messages.

     charon.receive_delay_type [0]
	    Specific IKEv2 message type to delay, 0 for any.

     charon.reject_trusted_end_entity [no]
	    Reject  peers  that  use trusted end-entity certificates (i.e. local
	    certificates).

     charon.replay_window [32]
	    Size of the AH/ESP replay window, in packets.

     charon.reqid_base [1]
	    Value of the first reqid to be automatically assigned to a CHILD_SA.

     charon.retransmit_base [1.8]
	    Base to use for calculating exponential back off, see IKEv2 RETRANS-
	    MISSION in strongswan.conf(5).

     charon.retransmit_jitter [0]
	    Maximum jitter in percent to apply randomly to  calculated	retrans-
	    mission timeout (0 to disable).

     charon.retransmit_limit [0]
	    Upper  limit  in seconds for calculated retransmission timeout (0 to
	    disable).

     charon.retransmit_timeout [4.0]
	    Timeout in seconds before sending first retransmit.

     charon.retransmit_tries [5]
	    Number of times to retransmit a packet before giving up.

     charon.retry_initiate_interval [0s]
	    Interval in seconds to use when retrying to initiate an IKE_SA (e.g.
	    if DNS resolution failed), 0 to disable retries.

     charon.reuse_ikesa [yes]
	    Initiate  CHILD_SA	within	existing  IKE_SAs  (always  enabled  for
	    IKEv1).

     charon.routing_table []
	    Numerical routing table to install routes to.

     charon.routing_table_prio []
	    Priority of the routing table.

     charon.rsa_pss [no]
	    Whether to use RSA with PSS padding instead of PKCS#1 padding by de-
	    fault.

     charon.rsa_pss_trailerfield [no]
	    Whether  to  encode  an  explicit  trailerField value of 0x01 in the
	    RSA-PSS algorithmIdentifier (CONTEXT3) or using the DEFAULT value by
	    omitting it.

     charon.send_delay [0]
	    Delay in ms for sending packets, to simulate larger RTT.

     charon.send_delay_request [yes]
	    Delay request messages.

     charon.send_delay_response [yes]
	    Delay response messages.

     charon.send_delay_type [0]
	    Specific IKEv2 message type to delay, 0 for any.

     charon.send_vendor_id [no]
	    Send strongSwan vendor ID payload

     charon.signature_authentication [yes]
	    Whether to enable Signature Authentication as per RFC 7427.

     charon.signature_authentication_constraints [yes]
	    If enabled, signature schemes configured in rightauth,  in	addition
	    to getting used as constraints against signature schemes employed in
	    the certificate chain, are also used as constraints against the sig-
	    nature scheme used by peers during IKEv2.

     charon.spi_label [0x0000000000000000]
	    Value mixed into the local IKE SPIs after applying spi_mask.

     charon.spi_mask [0x0000000000000000]
	    Mask  applied to local IKE SPIs before mixing in spi_label (bits set
	    will be replaced with spi_label).

     charon.spi_max [0xcfffffff]
	    The upper limit for SPIs requested from the kernel for IPsec SAs.

     charon.spi_min [0xc0000000]
	    The lower limit for SPIs requested from the kernel	for  IPsec  SAs.
	    Should not be set lower than 0x00000100 (256), as SPIs between 1 and
	    255 are reserved by IANA.

     charon.start-scripts
	    Section containing a list of scripts (name = path) that are executed
	    when the daemon is started.

     charon.stop-scripts
	    Section containing a list of scripts (name = path) that are executed
	    when the daemon is terminated.

     charon.syslog
	    Section  to  define  syslog  loggers,  see	LOGGER	CONFIGURATION in
	    strongswan.conf(5).

     charon.syslog.<facility>
	    <facility> is one of the supported	syslog	facilities,  see  LOGGER
	    CONFIGURATION in strongswan.conf(5).

     charon.syslog.<facility>.<subsystem> [<default>]
	    Loglevel for a specific subsystem.

     charon.syslog.<facility>.default [1]
	    Specifies  the  default loglevel to be used for subsystems for which
	    no specific loglevel is defined.

     charon.syslog.<facility>.ike_name [no]
	    Prefix each log entry with the connection name and a unique  numeri-
	    cal identifier for each IKE_SA.

     charon.syslog.<facility>.log_level [no]
	    Add the log level of each message after the subsystem (e.g. [IKE2]).

     charon.syslog.<facility>.map_level [-1]
	    The  default setting of -1 passes all messages to syslog using a log
	    level of LOG_INFO. A non-negative value maps the strongSwan specific
	    loglevels (0..4) to the syslog level starting at the specified  num-
	    ber. For example, a value of 5 (LOG_NOTICE) maps strongSwan loglevel
	    0  to  LOG_NOTICE,	level  1  to  LOG_INFO, and levels 2, 3 and 4 to
	    LOG_DEBUG. This allows (additional) filtering of log messages on the
	    syslog server.

     charon.syslog.identifier []
	    Global identifier used for an openlog(3) call, prepended to each log
	    message by syslog.	If not configured, openlog(3) is not called,  so
	    the value will depend on system defaults (often the program name).

     charon.threads [16]
	    Number  of	worker	threads in charon. Several of these are reserved
	    for long running tasks in internal modules and  plugins.  Therefore,
	    make  sure	you  don't  set  this  value too low. The number of idle
	    worker threads listed in ipsec statusall might be used as  indicator
	    on the number of reserved threads.

     charon.tls.cipher []
	    List of TLS encryption ciphers.

     charon.tls.ke_group []
	    List of TLS key exchange groups.

     charon.tls.key_exchange []
	    List of TLS key exchange methods.

     charon.tls.mac []
	    List of TLS MAC algorithms.

     charon.tls.send_certreq_authorities [yes]
	    Whether to include CAs in a server's CertificateRequest message. May
	    be disabled if clients can't handle a long list of CAs.

     charon.tls.signature []
	    List of TLS signature schemes.

     charon.tls.suites []
	    List of TLS cipher suites.

     charon.tls.version_max [1.2]
	    Maximum TLS version to negotiate.

     charon.tls.version_min [1.2]
	    Minimum TLS version to negotiate.

     charon.tnc.tnc_config [/etc/tnc_config]
	    TNC IMC/IMV configuration file.

     charon.user []
	    Name of the user the daemon changes to after startup.

     charon.x509.enforce_critical [yes]
	    Discard  certificates  with  unsupported  or unknown critical exten-
	    sions.

     charon-cmd
	    Section with settings specific to the CLI client `charon-cmd`.  Set-
	    tings  from  the `charon` section are not inherited, but many can be
	    used here as well.

     charon-cmd.load_modular [yes]
	    Load only explicitly enabled plugins

     charon-nm
	    Section  with  settings  specific  to  the	NetworkManager	 backend
	    `charon-nm`.   Settings from the `charon` section are not inherited,
	    but many can be used here as well. Defaults for  some  settings  are
	    chosen  very deliberately and should only be changed in case of con-
	    flicts.

     charon-nm.ca_dir [<default>]
	    Directory from which to load CA certificates if  no  certificate  is
	    configured.

     charon-nm.install_virtual_ip_on [lo]
	    Interface  on which virtual IP addresses are installed. Note that NM
	    also installs the virtual IPs on the XFRM interface.

     charon-nm.load_modular [yes]
	    Load only explicitly enabled plugins

     charon-nm.mtu [1400]
	    MTU for XFRM interfaces created by the NM plugin.

     charon-nm.plugins.kernel-netlink.fwmark [!210]
	    Make packets with this mark ignore the routing table.  Must  be  the
	    same mark set in charon-nm.plugins.socket-default.fwmark.

     charon-nm.plugins.socket-default.fwmark [210]
	    Mark  applied to IKE and ESP packets to ignore the routing table and
	    avoid routing loops when using XFRM interfaces.

     charon-nm.port [0]
	    Source port when  sending  packets	to  port  500.	Defaults  to  an
	    ephemeral port. May be set to 500 if firewall rules require a static
	    port.

     charon-nm.port_nat_t [0]
	    Source  port  when	sending  packets to port 4500 or a custom server
	    port. Defaults to an ephemeral port. May be  set  to  e.g.	4500  if
	    firewall rules require a static port.

     charon-nm.retransmit_base [1.4]
	    Base to use for calculating exponential back off, see IKEv2 RETRANS-
	    MISSION  in strongswan.conf(5).  Default retransmission settings for
	    charon-nm are deliberately lower to fail  and  possibly  reestablish
	    SAs more quickly.

     charon-nm.retransmit_timeout [2.0]
	    Timeout in seconds before sending first retransmit.

     charon-nm.retransmit_tries [3]
	    Number of times to retransmit a packet before giving up.

     charon-nm.routing_table [210]
	    Table  where routes via XFRM interface are installed. Should be dif-
	    ferent than the table used for the regular IKE  daemon  due  to  the
	    mark.

     charon-nm.routing_table_prio [210]
	    Priority of the routing table. Higher than the default priority used
	    for the regular IKE daemon.

     charon-nm.syslog.daemon.default [1]
	    Default to logging via syslog's daemon facility on level 1.

     charon-systemd.journal
	    Section  to configure native systemd journal logger, very similar to
	    the  syslog  logger  as  described	in   LOGGER   CONFIGURATION   in
	    strongswan.conf(5).

     charon-systemd.journal.<subsystem> [<default>]
	    Loglevel for a specific subsystem.

     charon-systemd.journal.default [1]
	    Specifies  the  default loglevel to be used for subsystems for which
	    no specific loglevel is defined.

     imv_policy_manager.command_allow []
	    Shell command to be executed with recommendation allow.

     imv_policy_manager.command_block []
	    Shell command to be executed with all other recommendations.

     imv_policy_manager.database []
	    Database URI for the database that stores the  package  information.
	    If	it  contains  a password, make sure to adjust the permissions of
	    the config file accordingly.

     imv_policy_manager.load [sqlite]
	    Plugins to load in IMV policy manager.

     libimcv.debug_level [1]
	    Debug level for a stand-alone libimcv library.

     libimcv.load [random nonce gmp pubkey x509]
	    Plugins to load in IMC/IMVs with stand-alone libimcv library.

     libimcv.plugins.imc-attestation.aik_blob []
	    AIK encrypted private key blob file.

     libimcv.plugins.imc-attestation.aik_cert []
	    AIK certificate file.

     libimcv.plugins.imc-attestation.aik_handle []
	    AIK object handle.

     libimcv.plugins.imc-attestation.aik_pubkey []
	    AIK public key file.

     libimcv.plugins.imc-attestation.hash_algorithm [sha384]
	    Preferred measurement hash algorithm.

     libimcv.plugins.imc-attestation.mandatory_dh_groups [yes]
	    Enforce mandatory Diffie-Hellman groups.

     libimcv.plugins.imc-attestation.nonce_len [20]
	    DH nonce length.

     libimcv.plugins.imc-attestation.pcr17_after []
	    PCR17 value after measurement.

     libimcv.plugins.imc-attestation.pcr17_before []
	    PCR17 value before measurement.

     libimcv.plugins.imc-attestation.pcr17_meas []
	    Dummy measurement value extended into PCR17 if the TBOOT log is  not
	    available.

     libimcv.plugins.imc-attestation.pcr18_after []
	    PCR18 value after measurement.

     libimcv.plugins.imc-attestation.pcr18_before []
	    PCR18 value before measurement.

     libimcv.plugins.imc-attestation.pcr18_meas []
	    Dummy  measurement value extended into PCR17 if the TBOOT log is not
	    available.

     libimcv.plugins.imc-attestation.pcr_info [no]
	    Whether to send pcr_before and pcr_after info.

     libimcv.plugins.imc-attestation.pcr_padding [no]
	    Whether to pad IMA SHA1  measurements  values  when  extending  into
	    SHA256 PCR bank.

     libimcv.plugins.imc-attestation.use_quote2 [yes]
	    Use Quote2 AIK signature instead of Quote signature.

     libimcv.plugins.imc-attestation.use_version_info [no]
	    Version Info is included in Quote2 signature.

     libimcv.plugins.imc-hcd.push_info [yes]
	    Send quadruple info without being prompted.

     libimcv.plugins.imc-hcd.subtypes []
	    Section to define PWG HCD PA subtypes.

     libimcv.plugins.imc-hcd.subtypes.<section> []
	    Defines  a	PWG  HCD  PA subtype section. Recognized subtype section
	    names are system, control, marker, finisher, interface and scanner.

     libimcv.plugins.imc-hcd.subtypes.<section>.<sw_type> []
	    Defines a software type section. Recognized  software  type  section
	    names are firmware, resident_application and user_application.

     libimcv.plugins.imc-hcd.subtypes.<section>.<sw_type>.<software> []
	    Defines a software section having an arbitrary name.

     libimcv.plugins.imc-hcd.subtypes.<section>.<sw_type>.<software>.name []
	    Name of the software installed on the hardcopy device.

     libimcv.plugins.imc-hcd.subtypes.<section>.<sw_type>.<software>.patches []
	    String  describing all patches applied to the given software on this
	    hardcopy device. The individual patches are separated by  a  newline
	    character '\\n'.

     libimcv.plugins.imc-hcd.subtypes.<section>.<sw_type>.<software>.string_ver-
     sion []
	    String describing the version of the given software on this hardcopy
	    device.

     libimcv.plugins.imc-hcd.subtypes.<section>.<sw_type>.<software>.version []
	    Hex-encoded  version string with a length of 16 octets consisting of
	    the fields major version number (4 octets), minor version number  (4
	    octets),  build  number  (4  octets),  service  pack major number (2
	    octets) and service pack minor number (2 octets).

     libimcv.plugins.imc-hcd.subtypes.<section>.attributes_natural_language [en]
	    Variable length natural language tag conforming to RFC  5646  speci-
	    fies  the  language to be used in the health assessment message of a
	    given subtype.

     libimcv.plugins.imc-hcd.subtypes.system.certification_state []
	    Hex-encoded certification state.

     libimcv.plugins.imc-hcd.subtypes.system.configuration_state []
	    Hex-encoded configuration state.

     libimcv.plugins.imc-hcd.subtypes.system.machine_type_model []
	    String specifying the machine type and model of the hardcopy device.

     libimcv.plugins.imc-hcd.subtypes.system.pstn_fax_enabled [no]
	    Specifies if a PSTN facsimile interface is installed and enabled  on
	    the hardcopy device.

     libimcv.plugins.imc-hcd.subtypes.system.time_source []
	    String  specifying	the  hostname of the network time server used by
	    the hardcopy device.

     libimcv.plugins.imc-hcd.subtypes.system.user_application_enabled [no]
	    Specifies if users can dynamically download and execute applications
	    on the hardcopy device.

     libimcv.plugins.imc-hcd.subtypes.system.user_application_persistence_en-
     abled [no]
	    Specifies if user dynamically downloaded  applications  can  persist
	    outside the boundaries of a single job on the hardcopy device.

     libimcv.plugins.imc-hcd.subtypes.system.vendor_name []
	    String specifying the manufacturer of the hardcopy device.

     libimcv.plugins.imc-hcd.subtypes.system.vendor_smi_code []
	    Integer  specifying  the globally unique 24-bit SMI code assigned to
	    the manufacturer of the hardcopy device.

     libimcv.plugins.imc-os.device_cert []
	    Manually set  the  path  to  the  client  device  certificate  (e.g.
	    /etc/pts/aikCert.der)

     libimcv.plugins.imc-os.device_handle []
	    Manually  set  handle  to  a private key bound to a smartcard or TPM
	    (e.g.  0x81010004)

     libimcv.plugins.imc-os.device_id []
	    Manually set the  client  device  ID  in  hexadecimal  format  (e.g.
	    1083f03988c9762703b1c1080c2e46f72b99cc31)

     libimcv.plugins.imc-os.device_pubkey []
	    Manually  set  the	path  to  the  client  device  public  key (e.g.
	    /etc/pts/aikPub.der)

     libimcv.plugins.imc-os.push_info [yes]
	    Send operating system info without being prompted.

     libimcv.plugins.imc-scanner.push_info [yes]
	    Send open listening ports without being prompted.

     libimcv.plugins.imc-swima.eid_epoch [0x11223344]
	    Set 32 bit epoch value for event IDs manually if software  collector
	    database is not available.

     libimcv.plugins.imc-swima.subscriptions [no]
	    Accept SW Inventory or SW Events subscriptions.

     libimcv.plugins.imc-swima.swid_database []
	    URI  to  software  collector  database  containing event timestamps,
	    software creation and deletion events and collected software identi-
	    fiers. If it contains a password, make sure to  adjust  the  permis-
	    sions of the config file accordingly.

     libimcv.plugins.imc-swima.swid_directory [${prefix}/share]
	    Directory where SWID tags are located.

     libimcv.plugins.imc-swima.swid_full [no]
	    Include file information in the XML-encoded SWID tags.

     libimcv.plugins.imc-swima.swid_pretty [no]
	    Generate XML-encoded SWID tags with pretty indentation.

     libimcv.plugins.imc-test.additional_ids [0]
	    Number of additional IMC IDs.

     libimcv.plugins.imc-test.command [none]
	    Command to be sent to the Test IMV.

     libimcv.plugins.imc-test.dummy_size [0]
	    Size of dummy attribute to be sent to the Test IMV (0 = disabled).

     libimcv.plugins.imc-test.retry [no]
	    Do a handshake retry.

     libimcv.plugins.imc-test.retry_command []
	    Command to be sent to the Test IMV in the handshake retry.

     libimcv.plugins.imv-attestation.cadir []
	    Path to directory with AIK cacerts.

     libimcv.plugins.imv-attestation.dh_group [ecp256]
	    Preferred Diffie-Hellman group.

     libimcv.plugins.imv-attestation.hash_algorithm [sha384]
	    Preferred measurement hash algorithm.

     libimcv.plugins.imv-attestation.mandatory_dh_groups [yes]
	    Enforce mandatory Diffie-Hellman groups.

     libimcv.plugins.imv-attestation.min_nonce_len [0]
	    DH minimum nonce length.

     libimcv.plugins.imv-os.remediation_uri []
	    URI pointing to operating system remediation instructions.

     libimcv.plugins.imv-scanner.remediation_uri []
	    URI pointing to scanner remediation instructions.

     libimcv.plugins.imv-swima.rest_api.timeout [120]
	    Timeout of SWID REST API HTTP POST transaction.

     libimcv.plugins.imv-swima.rest_api.uri []
	    HTTP URI of the SWID REST API.

     libimcv.plugins.imv-test.rounds [0]
	    Number of IMC-IMV retry rounds.

     libimcv.stderr_quiet [no]
	    Disable output to stderr with a stand-alone libimcv library.

     libimcv.swid_gen.command [/usr/local/bin/swid_generator]
	    SWID generator command to be executed.

     libimcv.swid_gen.tag_creator.name [strongSwan Project]
	    Name of the tagCreator entity.

     libimcv.swid_gen.tag_creator.regid [strongswan.org]
	    regid of the tagCreator entity.

     manager.database []
	    Credential database URI for manager. If it contains a password, make
	    sure to adjust the permissions of the config file accordingly.

     manager.debug [no]
	    Enable debugging in manager.

     manager.load []
	    Plugins to load in manager.

     manager.socket []
	    FastCGI socket of manager, to run it statically.

     manager.threads [10]
	    Threads to use for request handling.

     manager.timeout [15m]
	    Session timeout for manager.

     medsrv.database []
	    Mediation  server database URI. If it contains a password, make sure
	    to adjust the permissions of the config file accordingly.

     medsrv.debug [no]
	    Debugging in mediation server web application.

     medsrv.dpd [5m]
	    DPD timeout to use in mediation server plugin.

     medsrv.load []
	    Plugins to load in mediation server plugin.

     medsrv.password_length [6]
	    Minimum password length required for mediation server user accounts.

     medsrv.rekey [20m]
	    Rekeying time on mediation connections in mediation server plugin.

     medsrv.socket []
	    Run Mediation server web application statically on socket.

     medsrv.threads [5]
	    Number of thread for mediation service web application.

     medsrv.timeout [15m]
	    Session timeout for mediation service.

     pki.load []
	    Plugins to load in the pki tool.

     pki.scep.http_bind []
	    Source IP address to bind for HTTP operations.

     pki.scep.http_timeout [30s]
	    Timeout for HTTP operations.

     pki.scep.renewal_via_pkcs_req [no]
	    Some SCEP servers (e.g. openxpki) are incorrectly doing  certificate
	    renewal via messageType PKCSReq (19) instead of RenewalReq (17).

     pool.database []
	    Database URI for the database that stores IP pools and configuration
	    attributes.   If  it contains a password, make	  sure to adjust
	    the permissions of the config file accordingly.

     pool.load []
	    Plugins to load in ipsec pool tool.

     sec-updater
	    Options for the sec-updater tool.

     sec-updater.database []
	    Global IMV policy database URI. If it contains a password, make sure
	    to adjust the permissions of the config file accordingly.

     sec-updater.load []
	    Plugins to load in sec-updater tool.

     sec-updater.swid_gen.command [/usr/local/bin/swid_generator]
	    SWID generator command to be executed.

     sec-updater.swid_gen.tag_creator.name [strongSwan Project]
	    Name of the tagCreator entity.

     sec-updater.swid_gen.tag_creator.regid [strongswan.org]
	    regid of the tagCreator entity.

     sec-updater.tmp.deb_file [/tmp/sec-updater.deb]
	    Temporary storage for downloaded deb package file.

     sec-updater.tmp.tag_file [/tmp/sec-updater.tag]
	    Temporary storage for generated SWID tags.

     sec-updater.tnc_manage_command [/var/www/tnc/manage.py]
	    strongTNC manage.py command used to import SWID tags.

     starter.config_file [${sysconfdir}/ipsec.conf]
	    Location of the ipsec.conf file

     starter.load_warning [yes]
	    Disable charon plugin load option warning.

     sw-collector
	    Options for the sw-collector tool.

     sw-collector.database []
	    URI to software  collector	database  containing  event  timestamps,
	    software creation and deletion events and collected software identi-
	    fiers.  If	it  contains a password, make sure to adjust the permis-
	    sions of the config file accordingly.

     sw-collector.first_file [/var/log/bootstrap.log]
	    Path pointing to file created when the Linux OS was installed.

     sw-collector.first_time [0000-00-00T00:00:00Z]
	    Time in UTC when the Linux OS was installed.

     sw-collector.history []
	    Path pointing to apt history.log file.

     sw-collector.load []
	    Plugins to load in sw-collector tool.

     sw-collector.rest_api.timeout [120]
	    Timeout of REST API HTTP POST transaction.

     sw-collector.rest_api.uri []
	    HTTP URI of the central collector's REST API.

     swanctl.load []
	    Plugins to load in swanctl.

     swanctl.socket [unix://${piddir}/charon.vici]
	    VICI socket to connect to by default.

LOGGER CONFIGURATION
     Options in strongswan.conf(5) provide a much more flexible way to configure
     loggers for the IKE daemon charon than  using  the  charondebug  option  in
     ipsec.conf(5).

     Note: If any loggers are specified in strongswan.conf, charondebug does not
     have any effect.

     There are currently two types of loggers:

     File loggers
	    Log  directly to a file and are defined by specifying an arbitrarily
	    named subsection in the charon.filelog section. The full path to the
	    file is configured in the path setting of that subsection,	however,
	    if	it only contains characters permitted in section names, the set-
	    ting may also be omitted and the path specified as name of the  sub-
	    section.  To log to the console the two special filenames stdout and
	    stderr may be used.

     Syslog loggers
	    Log into a syslog facility and are defined by specifying the  facil-
	    ity  to log to as the name of a subsection in the charon.syslog sec-
	    tion. The following facilities are currently supported:  daemon  and
	    auth.

     Multiple  loggers can be defined for each type with different log verbosity
     for the different subsystems of the daemon.

   Subsystems
     dmn    Main daemon setup/cleanup/signal handling

     mgr    IKE_SA manager, handling synchronization for IKE_SA access

     ike    IKE_SA

     chd    CHILD_SA

     job    Jobs queueing/processing and thread pool management

     cfg    Configuration management and plugins

     knl    IPsec/Networking kernel interface

     net    IKE network communication

     asn    Low-level encoding/decoding (ASN.1, X.509 etc.)

     enc    Packet encoding/decoding encryption/decryption operations

     tls    libtls library messages

     esp    libipsec library messages

     lib    libstrongswan library messages

     tnc    Trusted Network Connect

     imc    Integrity Measurement Collector

     imv    Integrity Measurement Verifier

     pts    Platform Trust Service

   Loglevels
     -1     Absolutely silent

     0	    Very basic auditing logs, (e.g. SA up/SA down)

     1	    Generic control flow with errors, a good default to see what's going
	    on

     2	    More detailed debugging control flow

     3	    Including RAW data dumps in Hex

     4	    Also include sensitive material in dumps, e.g. keys

   Example
	  charon {
	       filelog {
		    charon {
			 path = /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
		    }
	       }
	  }

JOB PRIORITY MANAGEMENT
     Some operations in the IKEv2 daemon charon are currently  implemented  syn-
     chronously and blocking. Two examples for such operations are communication
     with  a RADIUS server via EAP-RADIUS, or fetching CRL/OCSP information dur-
     ing 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.

     To prevent thread starvation in such situations job priorities were  intro-
     duced.   The  job	processor  will reserve some threads for higher priority
     jobs, these threads are not available for lower priority, locking jobs.

   Implementation
     Currently 4 priorities have been defined, and they are used  in  charon  as
     follows:

     CRITICAL
	    Priority for long-running dispatcher jobs.

     HIGH   INFORMATIONAL exchanges, as used by liveness checking (DPD).

     MEDIUM
	    Everything not HIGH/LOW, including IKE_SA_INIT processing.

     LOW    IKE_AUTH message processing. RADIUS and CRL fetching block here

     Although IKE_SA_INIT processing is computationally expensive, it is explic-
     itly 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 ac-
     cepting more IKE_SA_INIT requests than it can handle, use IKE_SA_INIT DROP-
     PING.

     The  thread  pool processes jobs strictly by priority, meaning it will con-
     sume all higher priority jobs before looking for ones with lower  priority.
     Further,  it reserves threads for certain priorities. A priority class hav-
     ing reserved n threads will always have n threads available for this  class
     (either currently processing a job, or waiting for one).

   Configuration
     To  ensure that there are always enough threads available for higher prior-
     ity tasks, threads must be reserved for each priority class.

     charon.processor.priority_threads.critical [0]
	    Threads reserved for CRITICAL priority class jobs

     charon.processor.priority_threads.high [0]
	    Threads reserved for HIGH priority class jobs

     charon.processor.priority_threads.medium [0]
	    Threads reserved for MEDIUM priority class jobs

     charon.processor.priority_threads.low [0]
	    Threads reserved for LOW priority class jobs

     Let's consider the following configuration:

	  charon {
	       processor {
		    priority_threads {
			 high = 1
			 medium = 4
		    }
	       }
	  }

     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.

     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.

     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.

     The remaining threads  are  available  for  LOW  priority	jobs.  Reserving
     threads does not make sense (until we have an even lower priority).

   Monitoring
     To  see what the threads are actually doing, invoke ipsec statusall.  Under
     high load, something like this will show up:

	  worker threads: 2 or 32 idle, 5/1/2/22 working,
	       job queue: 0/0/1/149, scheduled: 198

     From 32 worker threads,

     2	    are currently idle.

     5	    are running CRITICAL priority jobs (dispatching from sockets, etc.).

     1	    is currently handling a HIGH priority  job.  This  is  actually  the
	    thread currently providing this information via stroke.

     2	    are  handling  MEDIUM  priority  jobs,  likely  IKE_SA_INIT  or CRE-
	    ATE_CHILD_SA messages.

     22     are handling LOW priority jobs, probably waiting for  an  EAP-RADIUS
	    response while processing IKE_AUTH messages.

     The  job queue load shows how many jobs are queued for each priority, ready
     for execution. The single MEDIUM priority job  will  get  executed  immedi-
     ately, as we have two spare threads reserved for MEDIUM class jobs.

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.

     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:

     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.

     charon.init_limit_job_load [0]
	    Limit  based  on  the number of jobs currently queued for processing
	    (sum over all job priorities).

     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.

     The  first  limit	is  simpler to calculate, but includes the load from new
     connections only. If your responder is  capable  of  negotiating  100  tun-
     nels/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
     (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.

LOAD TESTS
     To  do  stability	testing  and  performance  optimizations, the IKE daemon
     charon provides the load-tester plugin. This plugin  allows  one  to  setup
     thousands	of  tunnels  concurrently  against the daemon itself or a remote
     host.

     WARNING: Never enable the load-testing plugin  on	productive  systems.  It
     provides  preconfigured  credentials and allows an attacker to authenticate
     as any user.

   Configuration details
     For public key authentication, the responder  uses  the  "CN=srv,	OU=load-
     test,  O=strongSwan"  identity.  For the initiator, each connection attempt
     uses  a  different  identity   in	 the   form   "CN=c1-r1,   OU=load-test,
     O=strongSwan", where the first number indicates the client number, the sec-
     ond the authentication round (if multiple authentication rounds are used).

     For   PSK	authentication,  FQDN  identities  are	used.  The  server  uses
     srv.strongswan.org,   the	 client   uses	 an   identity	 in   the   form
     c1-r1.strongswan.org.

     For   EAP	 authentication,   the	 client   uses	 a   NAI   in  the  form
     100000000010001@strongswan.org.

     To configure multiple authentication rounds, concatenate  multiple  methods
     using, e.g.
	  initiator_auth = pubkey|psk|eap-md5|eap-aka

     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.

     To speed up testing, the load tester plugin implements  a	special  Diffie-
     Hellman implementation called modpnull. By setting
	  proposal = aes128-sha1-modpnull
     this  wicked  fast DH implementation is used. It does not provide any secu-
     rity at all, but allows one to run tests without DH calculation overhead.

   Examples
     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 fail, as each SA gets installed
     twice. To simulate the correct behavior, a fake kernel interface can be en-
     abled which does not install the IPsec SAs at the kernel level.

     A simple loopback configuration might look like this:

	  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
		    }
	       }
	  }

     This will initiate 4000 IKE_SAs within 20 seconds. You may increase the de-
     lay 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.

     The plugin also allows one 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:

	  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
		    }
	       }
	  }

IKEv2 RETRANSMISSION
     Retransmission  timeouts in the IKEv2 daemon charon can be configured glob-
     ally using the three keys listed below:

	    charon.retransmit_base [1.8]
	    charon.retransmit_timeout [4.0]
	    charon.retransmit_tries [5]
	    charon.retransmit_jitter [0]
	    charon.retransmit_limit [0]

     The following algorithm is used to calculate the timeout:

	  relative timeout = retransmit_timeout * retransmit_base ^ (n-1)

     Where n is the current retransmission count. The calculated  timeout  can't
     exceed  the  configured  retransmit_limit	(if any), which is useful if the
     number of retries is high.

     If a jitter in percent is configured, the timeout is modified as follows:

	  relative timeout -= random(0, retransmit_jitter * relative timeout)

     Using the default values, packets are retransmitted in:

     Retransmission   Relative Timeout	 Absolute Timeout
     -----------------------------------------------------
     1				    4s		       4s
     2				    7s		      11s
     3				   13s		      24s
     4				   23s		      47s
     5				   42s		      89s
     giving up			   76s		     165s

VARIABLES
     The variables used above are configured as follows:

     ${piddir}		     /var/run
     ${prefix}		     /usr/local
     ${sysconfdir}	     /usr/local/etc
     ${random_device}	     /dev/random
     ${urandom_device}	     /dev/urandom

FILES
     /usr/local/etc/strongswan.conf	  configuration file
     /usr/local/etc/strongswan.d/	  directory containing included config snippets
     /usr/local/etc/strongswan.d/charon/  plugin specific config snippets

SEE ALSO
     swanctl.conf(5),  swanctl(8),  ipsec.conf(5),  ipsec.secrets(5),  ipsec(8),
     charon-cmd(8)

HISTORY
     Written  for  the strongSwan project by Tobias Brunner, Andreas Steffen and
     Martin Willi.

6.0.7							      STRONGSWAN.CONF(5)

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