xref: /third_party/libwebsockets/LICENSE

Libwebsockets and included programs are provided under the terms of the
MIT license shown below, with the exception that some sources are under
a similar permissive license like BSD, or are explicitly CC0 / public
domain to remove any obstacles from basing differently-licensed code on
them.

Original liberal license retained:

  - lib/misc/sha-1.c                     - 3-clause BSD license retained, link to original [BSD3]
  - win32port/zlib                       - ZLIB license (see zlib.h) [ZLIB]
  - lib/tls/mbedtls/wrapper              - Apache 2.0 (only built if linked against mbedtls) [APACHE2]
    lib/tls/mbedtls/mbedtls-extensions.c
  - lib/misc/base64-decode.c             - already MIT
  - lib/misc/ieeehalfprecision.c         - 2-clause BSD license retained [BSD2]

Relicensed to MIT:

  - lib/misc/daemonize.c               - relicensed from Public Domain to MIT,
                                         link to original Public Domain version
  - lib/plat/windows/windows-resolv.c  - relicensed from "Beerware v42" to MIT

Public Domain (CC-zero) to simplify reuse:

  - test-apps/*.c
  - test-apps/*.h
  - minimal-examples/*
  - lwsws/*

Although libwebsockets is available under a permissive license, it does not
change the reality of dealing with large lumps of external code... if your
copy diverges it is guaranteed to contain security problems after a while
and can be very painful to pick backports (especially since historically,
we are very hot on cleaning and refactoring the codebase).  The least
painful and lowest risk way remains sending your changes and fixes upstream
to us so you can easily use later releases and fixes.

## MIT License applied to libwebsockets

https://opensource.org/licenses/MIT 

 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.

## BSD2

```
 *  Redistribution and use in source and binary forms, with or without 
 *  modification, are permitted provided that the following conditions are 
 *  met:
 *
 *     * Redistributions of source code must retain the above copyright 
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright 
 *       notice, this list of conditions and the following disclaimer in 
 *       the documentation and/or other materials provided with the distribution
 *      
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
 *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
 *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
 *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
 *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
 *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
 *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
 *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
 *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
 *  POSSIBILITY OF SUCH DAMAGE.
```

## BSD3

For convenience, a copy of the license on `./lib/misc/sha-1.c`.  In binary
distribution, this applies to builds with ws support enabled, and without
`LWS_WITHOUT_BUILTIN_SHA1` at cmake.

```
/*
 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH
```

## ZLIB

For convenience, a copy of the license on zlib.  In binary distribution,
this applies for win32 builds with internal zlib only.  You can avoid
building any zlib usage or copy at all with `-DLWS_WITH_ZLIB=0` (the
default), and so avoid needing to observe the license for binary
distribution that doesn't include the related code.

```
  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.

  Jean-loup Gailly        Mark Adler
  jloup@gzip.org          madler@alumni.caltech.edu
```


## APACHE2

For convenience, a copy of the license on the mbedtls wrapper part.  In binary
distribution, this applies only when building lws against mbedtls.

The canonical license application to source files uses the URL reference, so the
whole is not reproduced here.

```
// Copyright 2015-2016 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at

//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
```

## CC0

For convenience,the full text of CC0 dedication found on the lws examples.
The intention of this is to dedicate the examples to the public domain, so
users can build off and modify them without any constraint.

```
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