isakmpd(8)


NAME

     isakmpd --- ISAKMP/Oakley a.k.a. IKE key management daemon

SYNOPSIS

     isakmpd [-4] [-6] [-c config-file] [-a] [-d] [-D class=level] [-f fifo]
         [-i pid-file] [-n] [-p listen-port] [-P local-port] [-K] [-L]
         [-l packetlog-file] [-r seed] [-R report-file] [-v]

DESCRIPTION

     The isakmpd daemon establishes security associations for encrypted and/or
     authenticated network traffic.  At this moment, and probably forever,
     this means ipsec(4) traffic.

     The way isakmpd goes about its work is by maintaining an internal
     configuration as well as a policy database which describes what kinds of
     SAs to negotiate, and by listening for different events that trigger
     these negotiations.  The events that control isakmpd consist of
     negotiation initiations from a remote party, user input via a FIFO or by
     signals, upcalls from the kernel via a PF_KEY socket, and lastly by
     scheduled events triggered by timers running out.

     Most uses of isakmpd will be to implement so called "virtual private
     networks" or VPNs for short.  The vpn(8) manual page describes how to set
     up isakmpd for a simple VPN.  For other uses, some more knowledge of IKE
     as a protocol is required.  One source of information are the RFCs
     mentioned below.

     On startup isakmpd forks into two processes for privilege separation.
     The unprivileged child jails itself with chroot(8) to /var/empty.  The
     privileged process communicates with the child, reads configuration files
     and PKI information and binds to privileged ports on its behalf.  See
     CAVEATS section below.

     The options are as follows:

     -4 | -6
         These options control what address family (AF_INET and/or
         AF_INET6) isakmpd will use.  The default is to use both IPv4 and
         IPv6.

     -a      If given, isakmpd does not set up flows automatically.  This is
         useful when flows are configured with ipsecadm(4) or by other
         programs like bgpd(8).  Thus isakmpd only takes care of the SA
         establishment.

     -c config-file
         If given, the -c option specifies an alternate configuration file
         instead of /etc/isakmpd/isakmpd.conf.  As this file may contain
         sensitive information, it must be readable only by the user
         running the daemon.  isakmpd will reread the configuration file
         when sent a SIGHUP signal.

     -d      The -d option is used to make the daemon run in the foreground,
         logging to stderr.

     -D class=level
         Debugging class.  It's possible to specify this argument many
         times.  It takes a parameter of the form class=level, where both
         class and level are numbers.  class denotes a debugging class,
         and level the level you want that debugging class to limit debug
         printouts at (i.e., all debug printouts above the level specified
         will not output anything).  If class is set to 'A', then all
         debugging classes are set to the specified level.

         Valid values for class are as follows:

               0   Misc
               1   Transport
               2   Message
               3   Crypto
               4   Timer
               5   Sysdep
               6   SA
               7   Exchange
               8   Negotiation
               9   Policy
               10  FIFO user interface
               A   All

         Currently used values for level are 0 to 99.

     -f fifo
         The -f option specifies the FIFO (a.k.a. named pipe) where the
         daemon listens for user requests.  If the path given is a dash
         ('-'), isakmpd will listen to stdin instead.

     -i pid-file
         By default the PID of the daemon process will be written to
         /var/run/isakmpd.pid.  This path can be overridden by specifying
         another one as the argument to the -i option.

     -n      When the -n option is given, the kernel will not take part in the
         negotiations.  This is a non-destructive mode, so to speak, in
         that it won't alter any SAs in the IPsec stack.

     -p listen-port
         The -p option specifies the listen port the daemon will bind to.

     -P local-port
         On the other hand, the port specified to capital -P will be what
         the daemon binds its local end to when acting as initiator.

     -K      When this option is given, isakmpd does not read the policy
         configuration file and no keynote(4) policy check is
         accomplished.  This option can be used when policies for flows
         and SA establishment are arranged by other programs like
         ipsecadm(8) or bgpd(8).

     -L      Enable IKE packet capture.  When this option is given, isakmpd
         will capture to file an unencrypted copy of the negotiation
         packets it is sending and receiving.  This file can later be read
         by tcpdump(8) and other utilities using pcap(3).

     -l packetlog-file
         As option -L above, but capture to a specified file.

     -r seed
         If given, a deterministic random number sequence will be used
         internally.  This is useful for setting up regression tests.

     -R report-file
         When you signal isakmpd a SIGUSR1, it will report its internal
         state to a report file, normally /var/run/isakmpd.report, but
         this can be changed by feeding the file name as an argument to
         the -R flag.

     -v      Enables verbose logging.  Normally, isakmpd is silent and outputs
         only messages when a warning or an error occurs.  With verbose
         logging isakmpd reports successful completion of phase 1 (Main
         and Aggressive) and phase 2 (Quick) exchanges (Information and
         Transaction exchanges do not generate any additional status
         information).

   Setting up an IKE public key infrastructure (a.k.a. PKI)
     In order to use public key based authentication, there has to be an
     infrastructure managing the key signing.  Either there is an already
     existing PKI isakmpd should take part in, or there will be a need to set
     one up.  In the former case, what is needed to be done varies depending
     on the actual Certificate Authority used, and is therefore not covered
     here, other than mentioning that openssl(1) needs to be used to create a
     certificate signing request that the CA understands.  The latter case,
     however, is described here:

     1.   Create your own CA as root.

      # openssl genrsa -out /etc/ssl/private/ca.key 1024
      # openssl req -new -key /etc/ssl/private/ca.key \
              -out /etc/ssl/private/ca.csr

      You are then asked to enter information that will be incorporated
      into your certificate request.  What you are about to enter is what
      is called a Distinguished Name (DN).  There are quite a few fields
      but you can leave some blank.  For some fields there will be a
      default value; if you enter '.', the field will be left blank.

      # openssl x509 -req -days 365 -in /etc/ssl/private/ca.csr \
              -signkey /etc/ssl/private/ca.key \
              -extfile /etc/ssl/x509v3.cnf -extensions x509v3_CA \
              -out /etc/ssl/ca.crt

     2.   Create keys and certificates for your IKE peers.  This step as well
      as the next one, needs to be done for every peer.  Furthermore the
      last step will need to be done once for each ID you want the peer to
      have.  The 10.0.0.1 below symbolizes that ID, in this case an IPv4
      ID, and should be changed for each invocation.  You will be asked
      for a DN for each run.  Encoding the ID in the common name is
      recommended, as it should be unique.

      # openssl genrsa -out /etc/isakmpd/private/local.key 1024
      # openssl req -new -key /etc/isakmpd/private/local.key \
              -out /etc/isakmpd/private/10.0.0.1.csr

      Now take these certificate signing requests to your CA and process
      them like below.  You have to add a subjectAltName extension field
      to the certificate in order to make it usable by isakmpd.  There are
      two possible ways to add the extensions to the certificate.  Either
      you have to run certpatch(8) or you have to make use of an OpenSSL
      configuration file, for example /etc/ssl/x509v3.cnf.  Replace
      10.0.0.1 with the IP-address which isakmpd will use as the
      certificate identity.

      To use certpatch(8), do the following

      # openssl x509 -req -days 365 -in 10.0.0.1.csr -CA /etc/ssl/ca.crt \
              -CAkey /etc/ssl/private/ca.key -CAcreateserial \
              -out 10.0.0.1.crt
      # certpatch -i 10.0.0.1 -k /etc/ssl/private/ca.key \
              10.0.0.1.crt 10.0.0.1.crt

      Otherwise do

      # setenv CERTIP 10.0.0.1
      # openssl x509 -req -days 365 -in 10.0.0.1.csr -CA /etc/ssl/ca.crt \
              -CAkey /etc/ssl/private/ca.key -CAcreateserial \
              -extfile /etc/ssl/x509v3.cnf -extensions x509v3_IPAddr \
              -out 10.0.0.1.crt

      For a FQDN certificate, do

      # setenv CERTFQDN somehost.somedomain
      # openssl x509 -req -days 365 -in somehost.somedomain.csr \
              -CA /etc/ssl/ca.crt -CAkey /etc/ssl/private/ca.key \
              -CAcreateserial \
              -extfile /etc/ssl/x509v3.cnf -extensions x509v3_FQDN \
              -out somehost.somedomain.crt

      or with certpatch(8)

      # certpatch -t fqdn -i somehost.somedomain \
              -k /etc/ssl/private/ca.key \
              somehost.somedomain.crt somehost.somedomain.crt

      (This assumes the previous steps were used to create a request for
      somehost.somedomain instead of 10.0.0.1)

      Put the certificate (the file ending in .crt) in /etc/isakmpd/certs/
      on your local system.  Also carry over the CA cert /etc/ssl/ca.crt
      and put it in /etc/isakmpd/ca/.

     To revoke certificates, create a Certificate Revocation List (CRL) file
     and install it in the /etc/isakmpd/crls/ directory.  See openssl(1) and
     the 'crl' subcommand for more info.

     It is also possible to store trusted public keys to make them directly
     usable by isakmpd.  The keys should be saved in PEM format (see
     openssl(1)) and named and stored after this easy formula:

     For IPv4 identities   /etc/isakmpd/pubkeys/ipv4/A.B.C.D

     For IPv6 identities   /etc/isakmpd/pubkeys/ipv6/abcd:abcd::ab:bc

     For FQDN identities   /etc/isakmpd/pubkeys/fqdn/foo.bar.org

     For UFQDN identities  /etc/isakmpd/pubkeys/ufqdn/user@foo.bar.org

   The FIFO user interface
     When isakmpd starts, it creates a FIFO (named pipe) where it listens for
     user requests.  All commands start with a single letter, followed by
     command-specific options.  Available commands are:

     c <name>
         Start the named connection, if stopped or inactive.

     C set [section]:tag=value
     C set [section]:tag=value force
     C add [section]:tag=value
     C rm  [section]:tag
     C rms [section]
         Update the running isakmpd configuration atomically.  'set' sets
         a configuration value consisting of a section, tag and value
         triplet.  'set' will fail if the configuration already contains a
         section with the named tag; use the 'force' option to change this
         behaviour.  'add' appends a configuration value to the named
         configuration list tag.  'rm' removes a tag in a section.  'rms'
         removes an entire section.

         NOTE: Sending isakmpd a SIGHUP or an "R" through the FIFO will
         void any updates done to the configuration.

     C get [section]:tag
         Get the configuration value of the specified section and tag.
         The result is stored in /var/run/isakmpd.result.

     d <cookies> <msgid>
         Delete the specified SA from the system.  Specify <msgid> as "-"
         to match a Phase 1 SA.

     D <class> <level>
     D A <level>
     D T     Set debug class <class> to level <level>.  If <class> is
         specified as "A", the level applies to all debug classes.  "D T"
         toggles all debug classes to level zero.  Another "D T" command
         will toggle them back to the earlier levels.

     p on[=<path>]
     p off   Enable or disable cleartext IKE packet capture.  When enabling,
         optionally specify which file isakmpd should capture the packets
         to.

     Q       Cleanly shutdown the daemon, as when sent a SIGTERM signal.

     r       Report isakmpd internal state to a file.  See -R option.  Same as
         when sent a SIGUSR1 signal.

     R       Reinitialize isakmpd, as when sent a SIGHUP signal.

     S       Report information on all known SAs to the
         /var/run/isakmpd.result file.

     t <name>
         Tear down the named connection, if active.

     T       Tear down all active connections.

FILES

     /etc/isakmpd/ca/             The directory where CA certificates can be
                              found.

     /etc/isakmpd/certs/          The directory where IKE certificates can be
                              found, both the local certificate(s) and
                              those of the peers, if a choice to have them
                              kept permanently has been made.

     /etc/isakmpd/crls/           The directory where CRLs can be found.

     /etc/isakmpd/isakmpd.conf    The configuration file.  As this file can
                              contain sensitive information it must not be
                              readable by anyone but the user running
                              isakmpd.

     /etc/isakmpd/isakmpd.policy  The keynote policy configuration file.  The
                              same mode requirements as isakmpd.conf.

     /etc/isakmpd/private/local.key
                              A local private key for certificate based
                              authentication.  There has to be a
                              certificate for this key in the certificate
                              directory mentioned above.  The same mode
                              requirements as isakmpd.conf.

     /etc/isakmpd/pubkeys/        Directory in which trusted public keys can
                              be kept.  The keys must be named in the
                              fashion described above.

     /var/run/isakmpd.pid         The PID of the current daemon.

     /var/run/isakmpd.fifo        The FIFO used to manually control isakmpd.

     /var/run/isakmpd.pcap        The default IKE packet capture file.

     /var/run/isakmpd.report      The report file written when SIGUSR1 is
                              received.

     /var/run/isakmpd.result      The report file written when the 'S' or 'C
                              get' command is issued in the command FIFO.

     /usr/share/ipsec/isakmpd/    A directory containing some sample isakmpd
                              and keynote policy configuration files.

SEE ALSO

     openssl(1), getnameinfo(3), pcap(3), ipsec(4), isakmpd.conf(5),
     isakmpd.policy(5), ssl(8), tcpdump(8), vpn(8)

HISTORY

     The ISAKMP/Oakley key management protocol is described in the RFCs RFC
     2407, RFC 2408 and RFC 2409.  This implementation was done 1998 by Niklas
     Hallqvist and Niels Provos, sponsored by Ericsson Radio Systems.

CAVEATS

     When storing a trusted public key for an IPv6 identity, the most
     efficient form of address representation, i.e "::" instead of ":0:0:0:",
     must be used or the matching will fail.  isakmpd uses the output from
     getnameinfo(3) for the address-to-name translation.  The privileged
     process only allows binding to the default port 500 or unprivileged ports
     (>1024).  It is not possible to change the interfaces isakmpd listens on
     without a restart.

BUGS

     The -P flag does not do what we document, rather it does nothing.





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