BSD License

Copyright (C) 2017-2019 Baidu, Inc. All Rights Reserved.

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.
  * Neither the name of Baidu, Inc., 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 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.


===========================================================================================================================================================

Rust SGX SDK software for Linux also uses third-party projects that may be distributed under different licenses. Please see below for details.


1. Intel(R) SGX

Copyright (C) 2011-2017 Intel Corporation. All rights reserved.

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.
  * Neither the name of Intel Corporation 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 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.


2. Rust Project

                              Apache License
                        Version 2.0, January 2004
                     http://www.apache.org/licenses/

TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION

1. Definitions.

   "License" shall mean the terms and conditions for use, reproduction,
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   whether in tort (including negligence), contract, or otherwise,
   unless required by applicable law (such as deliberate and grossly
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   Work (including but not limited to damages for loss of goodwill,
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END OF TERMS AND CONDITIONS

APPENDIX: How to apply the Apache License to your work.

   To apply the Apache License to your work, attach the following
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Copyright [yyyy] [name of copyright owner]

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

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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.


3. compiler_rt

The compiler_rt library is dual licensed under both the University of Illinois
"BSD-Like" license and the MIT license.  As a user of this code you may choose
to use it under either license.  As a contributor, you agree to allow your code
to be used under both.

Full text of the relevant licenses is included below.

=============================================================================

University of Illinois/NCSA
Open Source License

Copyright (c) 2009-2013 by the contributors listed in CREDITS.TXT

All rights reserved.

Developed by:

    LLVM Team

    University of Illinois at Urbana-Champaign

    http://llvm.org

Permission is hereby granted, free of charge, to any person obtaining a copy of this
software and associated documentation files (the "Software"), to deal with 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:

-	Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimers.

-	Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimers in the documentation and/or
other materials provided with the distribution.

-	Neither the names of the LLVM Team, University of Illinois at Urbana-Champaign,
nor the names of its contributors may be used to endorse or romote products derived
from this Software without specific prior written permission.

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 CONTRIBUTORS 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 WITH THE SOFTWARE.

=============================================================================

Copyright (c) 2009-2013 by the contributors listed in CREDITS.TXT

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.

=============================================================================
Copyrights and Licenses for Third Party Software Distributed with LLVM:
=============================================================================
The LLVM software contains code written by third parties.  Such software will have its
own individual LICENSE.TXT file in the directory in which it appears.
This file will describe the copyrights, license, and restrictions which apply to that code.

The disclaimer of warranty in the University of Illinois Open Source License applies to all
code in the LLVM Distribution, and nothing in any of the other licenses gives permission to
use the names of the LLVM Team or the University of Illinois to endorse or promote products
derived from this Software.

The following pieces of software have additional or alternate copyrights, licenses, and/or
restrictions:

Program             Directory
-------             ---------
mach_override       lib/interception/mach_override


4. NetBSD

===============================================================================================

/*-
 * Copyright (c) 2008 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */
________________________________________
For complete copyright and licensing terms, see: http://www.netbsd.org/about/redistribution.html


5. OpenBSD

http://openbsd.org/

OpenBSD* Copyright Policy
________________________________________
-	Goal
Copyright law is complex, OpenBSD* policy is simple - OpenBSD strives to maintain the spirit
of the original Berkeley Unix copyrights.
OpenBSD can exist as it does today because of the example set by the Computer Systems Research
Group at Berkeley and the battles which they and others fought to create a relatively
un-encumbered Unix source distribution.
The ability of a freely redistributable "Berkeley" Unix to move forward on a competitive
basis with other operating systems depends on the willingness of the various development
groups to exchange code amongst themselves and with other projects. Understanding the legal
issues surrounding copyright is fundamental to the ability to exchange and re-distribute code,
while honoring the spirit of the copyright and concept of attribution is fundamental to
promoting the cooperation of the people involved.
-	The Berkeley* Copyright
The Berkeley* copyright poses no restrictions on private or commercial use of the software
and imposes only simple and uniform requirements for maintaining copyright notices in
redistributed versions and crediting the originator of the material only in advertising.
For instance:
 * Copyright (c) 1982, 1986, 1990, 1991, 1993
 *	The Regents of the University of California.  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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
 *
Berkeley rescinded the 3rd term (the advertising term) on 22 July 1999. Verbatim copies
of the Berkeley license in the OpenBSD tree have that term removed. In addition, many
3rd-party BSD-style licenses consist solely of the first two terms.
Because the OpenBSD copyright imposes no conditions beyond those imposed by the Berkeley
copyright, OpenBSD can hope to share the same wide distribution and applicability as the
Berkeley distributions. It follows however, that OpenBSD cannot include material which
includes copyrights which are more restrictive than the Berkeley copyright, or must
relegate this material to a secondary status, i.e. OpenBSD as a whole is freely
redistributable, but some optional components may not be.
-	Copyright Law
While the overall subject of copyright law is far beyond the scope of this document, some
basics are in order. Under the current copyright law, copyrights are implicit in the
creation of a new work and reside with the creator, unless otherwise assigned. In general
the copyright applies only to the new work, not the material the work was derived from,
nor those portions of the derivative material included in the new work.
Copyright law admits to three general categories of works:
Original Work
A new work that is not derived from an existing work.
Derivative Work
Work that is derived from, includes or amends existing works.
Compilations
A work that is a compilation of existing new and derivative works.
The fundamental concept is that there is primacy of the copyright, that is a copyright of a
derivative work does not affect the rights held by the owner of the copyright of the original
work, rather only the part added. Likewise the copyright of a compilation does not affect the
rights of the owner of the included works, only the compilation as an entity.
It is vitally important to understand that copyrights are broad protections as defined by
national and international copyright law. The "copyright notices" usually included in source
files are not copyrights, but rather notices that a party asserts that they hold copyright
to the material or to part of the material. Typically these notices are associated with
license terms which grant permissions subject to copyright law and with disclaimers that
state the position of the copyright holder/distributor with respect to liability surrounding
use of the material.
-	Permissions - the flip side
Because copyrights arise from the creation of a work, rather than through a registration process,
there needs to be a practical way to extend permission to use a work beyond what might be allowed
by "fair use" provisions of the copyright laws.
This permission typically takes the form of a "release" or "license" included in the work, which
grants the additional uses beyond those granted by copyright law, usually subject to a variety of
conditions. At one extreme sits "public domain" where the originator asserts that he imposes no
restrictions on use of the material, at the other restrictive clauses that actually grant no
additional rights or impose restrictive, discriminatory or impractical conditions on use of the
work.
Again, an important point to note is that the release and conditions can only apply to the
portion of the work that was originated by the copyright holder - the holder of a copyright
on a derivative work can neither grant additional permissions for use of the original work,
nor impose more restrictive conditions for use of that work.
Because copyright arises from the creation of a work and not the text or a registration process,
removing or altering a copyright notice or associated release terms has no bearing on the
existence of the copyright, rather all that is accomplished is to cast doubt upon whatever rights
the person making the modifications had to use the material in the first place. Likewise, adding
terms and conditions in conflict with the original terms and conditions does not supersede them,
rather it casts doubts on the rights of the person making the amendments to use the material and
creates confusion as to whether anyone can use the amended version or derivatives thereof.
Finally, releases are generally binding on the material that they are distributed with. This means
that if the originator of a work distributes that work with a release granting certain permissions,
those permissions apply as stated, without discrimination, to all persons legitimately possessing
a copy of the work. That means that having granted a permission, the copyright holder can not
retroactively say that an individual or class of individuals are no longer granted those permissions.
Likewise should the copyright holder decide to "go commercial" he can not revoke permissions already
granted for the use of the work as distributed, though he may impose more restrictive permissions in
his future distributions of that work.
-	Specific Cases
This section attempts to summarize the position of OpenBSD relative to some commonly encountered
copyrights.
Berkeley*
The Berkeley copyright is the model for the OpenBSD copyright. It retains the rights of the
copyright holder, while imposing minimal conditions on the use of the copyrighted material.
Material with Berkeley copyrights, or copyrights closely adhering to the Berkeley model can
generally be included in OpenBSD.
AT&amp;T*
As part of its settlement with AT&amp;T*, Berkeley included an AT&amp;T copyright notice on some of the
files in 4.4BSD lite and lite2. The terms of this license are identical to the standard Berkeley
license.
Additionally, OpenBSD includes some other AT&amp;T code with non-restrictive copyrights, such as the
reference implementation of awk.
Caldera*
Caldera* (now known as the SCO group) is the current owner of the Unix code copyrights. On 23
January 2002, the original Unix code (versions 1 through seven, including 32V) was freed by Caldera.
This code is now available under a 4-term BSD-style license. As a result, it is now possible to
incorporate real Unix code into OpenBSD (though this code is quite old and generally requires significant
changes to bring it up to date).
DEC*, Sun*, other manufacturers/software houses.
In general OpenBSD does not include material copyrighted by manufacturers or software houses.
Material may be included where the copyright owner has granted general permission for reuse
without conditions, with terms similar to the Berkeley copyright, or where the material is the
product of an employee and the employer's copyright notice effectively releases any rights they
might have to the work.
Carnegie-Mellon* (CMU, Mach)
The Carnegie-Mellon copyright is similar to the Berkeley copyright, except that it requests that
derivative works be made available to Carnegie-Mellon. Because this is only a request and not a
condition, such material can still be included in OpenBSD. It should be noted that existing
versions of Mach are still subject to AT&amp;T copyrights, which prevents the general distribution
of Mach sources.
Apache*
The original Apache* copyright is similar to the Berkeley copyright, except that it stipulates
that products derived from the code may not have "Apache" in their name. The purpose of this
clause is to avoid a situation in which another party releases a modified version of the code
named in such a way to make users think that it is the "official" version. This is not an issue
with OpenBSD because OpenBSD is a Compilation, and not a Derived Work. Source code published under
version 2 of the Apache license cannot be included into OpenBSD. As a consequence, OpenBSD now
maintains its own version of Apache based on version 1.3.29. The OpenBSD version includes many
enhancements and bugfixes.
ISC*
The ISC* copyright is functionally equivalent to a two-term BSD copyright with language removed
that is made unnecessary by the Berne convention. This is the preferred license for new code
incorporated into OpenBSD. A sample license is included in the source tree as
/usr/src/share/misc/license.template.
GNU* General Public License, GPL, LGPL, copyleft, etc.
The GNU* Public License and licenses modeled on it impose the restriction that source code must
be distributed or made available for all works that are derivatives of the GNU copyrighted code.
While this may be a noble strategy in terms of software sharing, it is a condition that is
typically unacceptable for commercial use of software. As a consequence, software bound by the
GPL terms can not be included in the kernel or "runtime" of OpenBSD, though software subject to
 GPL terms may be included as development tools or as part of the system that are "optional" as
long as such use does not result in OpenBSD as a whole becoming subject to the GPL terms.
As an example, GCC and other GNU tools are included in the OpenBSD tool chain. However, it is
quite possible to distribute a system for many applications without a tool chain, or the
distributor can choose to include a tool chain as an optional bundle which conforms to the
GPL terms.
NetBSD*
Much of OpenBSD is originally based on and evolved from NetBSD*, since some of the OpenBSD
developers were involved in the NetBSD project. The general NetBSD license terms are compatible
with the Berkeley license and permit such use. Material subject only to the general NetBSD license
can generally be included in OpenBSD.
In the past, NetBSD has included material copyrighted by individuals who have imposed license
conditions beyond that of the general NetBSD license, but granted the NetBSD Foundation license
to distribute the material. Such material can not be included in OpenBSD as long as the conditions
imposed are at odds with the OpenBSD license terms or releases from those terms are offered on a
discriminatory basis.
FreeBSD*
Most of FreeBSD* is also based on Berkeley licensed material or includes copyright notices based
on the Berkeley model. Such material can be included in OpenBSD, while those parts that are subject
to GPL or various individual copyright terms that are at odds with the OpenBSD license can not be
included in OpenBSD.
Linux*
Most of Linux* is subject to GPL style licensing terms and therefore can not be included in
OpenBSD. Individual components may be eligible, subject to the terms of the originator's copyright
notices. Note that Linux "distributions" may also be subject to additional copyright claims of the
distributing organization, either as a compilation or on material included that is not part of the
Linux core.
X*, XFree86*, X.Org*
X*, X.Org* or XFree86* are not parts of OpenBSD, rather X.Org and parts of XFree86 3.3.6 are
distributed with many OpenBSD ports as a convenience to the user, subject to applicable license
terms.
Shareware, Charityware, Freeware, etc.
Most "shareware" copyright notices impose conditions for redistribution, use or visibility that
are at conflict with the OpenBSD project goals. Review on a case-by-case basis is required as to
whether the wording of the conditions is acceptable in terms of conditions being requested vs.
demanded and whether the spirit of the conditions is compatible with goals of the OpenBSD project.
Public Domain
While material that is truly entered into the "Public Domain" can be included in OpenBSD, review
is required on a case by case basis. Frequently the "public domain" assertion is made by someone
who does not really hold all rights under Copyright law to grant that status or there are a variety
of conditions imposed on use. For a work to be truly in the "Public Domain" all rights are abandoned
and the material is offered without restrictions.