Hippotat - Asinine IP Over HTTP program

Copyright 2017,2019-2022 Ian Jackson and contributors to Hippotat

The client and server are:

 GPLv3+

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program, in the file GPLv3.  If not,
    see <http://www.gnu.org/licenses/>.

On a Debian system, the GNU General Public License v3 can be found in
/usr/share/common-licenses/GPL-3


Formalities
-----------

The licence is generally indicated in each file with an SPDX
delcaration; as is conventional, this should be read as a licence
grant.

Contributions to Hippotat are accepted based on the git commit
Signed-off-by convention, by which the contributors' certify their
contributions according to the Developer Certificate of Origin version
1.1 - see the file DEVELOPER-CERTIFICATE.

If you create a new file please be sure to add an appropriate licence
header, probably something like this:
// Copyright 2017-2022 Ian Jackson and contributors to Hippotat
// SPDX-License-Identifier: AGPL-3.0-or-later
// There is NO WARRANTY.


OpenSSL Licence Exception
-------------------------

Additional permission under GNU GPL version 3 section 7
[LicenseRef-Hippotat-OpenSSL-Exception]:

    In addition, as a special exception, the copyright holders give
    permission to link the code of this program with the OpenSSL
    Library (or with modified versions of OpenSSL that use the same
    license as OpenSSL 1.1), and distribute linked combinations
    including the two.

    BUT this does NOT apply to version 3.0 or any later version of the
    OpenSSL library (nor to any modified versions thereof).  (We make
    this restriction because the exception is not needed with OpenSSL 3.)

    FURTHERMORE to take advantage of this exception you must obey the
    GNU Lesser General Public License (version 3, or, at your option,
    any later version) in all respects for all of the code used other
    than OpenSSL.

This additional permission is indicated in the source code with
the following SPDX licence declaration:
    SPDX-License-Identifier: GPL-3.0-or-later WITH LicenseRef-Hippotat-OpenSSL-Exception
(which is roughly but not exactly in accordance with the SPDX spec.)

If you modify a file, you may extend this exception to your version of
the file, but you are not obligated to do so. If you do not wish to do
so, delete the exception statement from your version, changing it to:
    SPDX-License-Identifier: GPL-3.0-or-later

The authors of Hippotat will probably withdrawn this exception in a
future versions of Hippotat, when OpenSSL 3.0 (which has a
GPLv3+-compatible licence) has become sufficiently widespread.  But
that will not affect already-released versions of hippotat.


Licences of other code in the source tree
-----------------------------------------

The uml/ directory contains some currently non-functional test
arrangements.  This is not currently used (or built or installed).

Within this directory there is:

uml/rndaddtoentcnt/

  MIT License

  Copyright (c) 2018 Jumpnow Technologies, LLC

  Permission is hereby granted, free of charge, to any person
  obtaining a copy of this software and associated documentation files
  (the "Software"), to deal in the Software without restriction,
  including without limitation the rights to use, copy, modify, merge,
  publish, distribute, sublicense, and/or sell copies of the Software,
  and to permit persons to whom the Software is furnished to do so,
  subject to the following conditions:

  The above copyright notice and this permission notice shall be
  included in all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  SOFTWARE.

uml/psusan-*/

Contains an example by Simon Tatham taken from the PuTTY documentation.

  PuTTY is copyright 1997-2022 Simon Tatham.

  Portions copyright Robert de Bath, Joris van Rantwijk, Delian
  Delchev, Andreas Schultz, Jeroen Massar, Wez Furlong, Nicolas Barry,
  Justin Bradford, Ben Harris, Malcolm Smith, Ahmad Khalifa, Markus
  Kuhn, Colin Watson, Christopher Staite, Lorenz Diener, Christian
  Brabandt, Jeff Smith, Pavel Kryukov, Maxim Kuznetsov, Svyatoslav
  Kuzmich, Nico Williams, Viktor Dukhovni, Josh Dersch, Lars
  Brinkhoff, and CORE SDI S.A.

  Permission is hereby granted, free of charge, to any person
  obtaining a copy of this software and associated documentation files
  (the "Software"), to deal in the Software without restriction,
  including without limitation the rights to use, copy, modify, merge,
  publish, distribute, sublicense, and/or sell copies of the Software,
  and to permit persons to whom the Software is furnished to do so,
  subject to the following conditions:

  The above copyright notice and this permission notice shall be
  included in all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  NONINFRINGEMENT. IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE
  FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
  CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
