RADIUS attribute from rfc2865


Reply-Message

This Attribute indicates text which MAY be displayed to the user.

      When used in an Access-Accept, it is the success message.

      When used in an Access-Reject, it is the failure message.  It MAY
      indicate a dialog message to prompt the user before another
      Access-Request attempt.

      When used in an Access-Challenge, it MAY indicate a dialog message
      to prompt the user for a response.

      Multiple Reply-Message's MAY be included and if any are displayed,
      they MUST be displayed in the same order as they appear in the
      packet.

   A summary of the Reply-Message Attribute format is shown below.  The
   fields are transmitted from left to right.

    0                   1                   2
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
   |     Type      |    Length     |  Text ...
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-

   Type

      18 for Reply-Message.

   Length

      >= 3

   Text

      The Text field is one or more octets, and its contents are
      implementation dependent.  It is intended to be human readable,
      and MUST NOT affect operation of the protocol.  It is recommended
      that the message contain UTF-8 encoded 10646  characters.