@SYNTAX:key@

This command is used to set and unset private keys for
channels, set and unset private keys for private messages
with remote clients and to send key agreement requests and
negotiate the key agreement protocol with remote client.
The key agreement is supported only to negotiate private
message keys, it currently cannot be used to negotiate
private keys for channels, as it is not convenient for that
purpose.

Types:

    MSG        The command is performed for private messages
               affecting the <nickname>.

    CHANNEL    The command is performed for channel affecting
               the <channel>.

Commands:

    set        [<key> [<cipher>] [<hmac>]]

      Set the key into use.  If the <key> is provided it
      is used as the key material.  If the <key> is not
      provided the negotiated key material is used.  If
      the negotiation has not been performed this command
      has no effect.

      If the type is `msg' and the <key> is `*' then
      random key will be generated automatically.

      The <cipher> may be set for both private message
      and channel private keys and the <hmac> may be set
      only to the channel private keys.

    unset      [<number>]

      Unset the key.  The private key is not used after
      this command.  The key must be set again or the key
      material must be re-negotiated to be able to use
      the private keys again.

      The channel may have several private keys set.  The
      <number> can be used to indicate what key is being
      unset.  If it is not provided all keys are removed.

    list

      List all private keys that has been set.  If the
      type is `msg' and the <nickname> is ´*' then
      all private message keys that you've set will be
      listed.

    agreement  [<hostname> [<port>]]

      Send key agreement request to remote client.  If
      the <hostname> is provided it is sent in the request.
      The receiver may use the hostname to start the
      key agreement.  If the <port> is also provided your
      key agreement protocol server is bound to that
      port.  Note that it cannot be privileged port (<1024).
      If the <hostname> and <port> is not provided then
      the receiver will never initiate the key agreement.
      In this case you may start the key agreement after
      receiving the reply to the request, by giving the
      negotiate command.

      This command may be used to send reply to the
      remote client.  When receiving empty key agreement
      you can reply to the sender with the hostname and
      port of your key agreement server with this command.

    negotiate  [<hostname> [<port>]]

      This may be called to start the key agreement with
      <nickname>.  This command has effect only if the
      <nickname> has replied to your key agreement request.
      You will see a notify on the screen when the reply
      arrives.  The <hostname> and <port> is the hostname
      and port of the remote client's key agreement
      server.