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PKWARE, Inc., Third-Party License Summary for ZIP Reader

The PKWARE ZIP Reader product makes use of software modules or code developed by one or more third parties. This document identifies the licensing information governing this third-party software.

PKWARE, the PKWARE Logo, PKZIP, SecureZIP, ZIP Reader and PKSFX are registered trademarks of PKWARE, Inc. Trademarks of other companies mentioned here appear for identification purposes only and are the property of their respective companies.


AES Decryption Routines by Dr. Brian Gladman

Below are given the license and disclaimer for software written by Dr. Brian Gladman for implementing decryption for AES.

Copyright (c) 2002, Dr Brian Gladman <This email address is being protected from spambots. You need JavaScript enabled to view it.>, Worcester, UK.  All rights reserved.

LICENSE TERMS

The free distribution and use of this software in both source and binary form is allowed (with or without changes) provided that:

Distributions of this source code include the above copyright notice, this list of conditions and the following disclaimer;

Distributions in binary form include the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other associated materials;

The copyright holder's name is not used to endorse products built using this software without specific written permission.

ALTERNATIVELY, provided that this notice is retained in full, this product  may be distributed under the terms of the GNU General Public License (GPL),  in which case the provisions of the GPL apply INSTEAD OF those given above.

DISCLAIMER

This software is provided 'as is' with no explicit or implied warranties  in respect of its properties, including, but not limited to, correctness  and/or fitness for purpose.



BZIP2

Below are given the license and disclaimer for BZIP2.

This program, "bzip2", the associated library "libbzip2", and all documentation, are copyright (C) 1996-2005 Julian R Seward.  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. 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.
  3. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
  4. The name of the author may not be used to endorse or promote products derived from this software without specific prior written permission.
  5. THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.


    CRC-32

    Below are given the license and disclaimer for CRC-32.

    /* crc32.c -- compute the CRC-32 of a data stream
     * Copyright (C) 1995-2003 Mark Adler
     * For conditions of distribution and use, see  copyright notice in zlib.h
     *
     * Thanks to Rodney Brown <This email address is being protected from spambots. You need JavaScript enabled to view it.>  for his contribution of faster
     * CRC methods: exclusive-oring 32 bits of data at a  time, and pre-computing
     * tables for updating the shift register in one step  with three exclusive-ors
     * instead of four steps with four exclusive-ors.   This results about a factor
     * of two increase in speed on a Power PC G4 (PPC7455)  using gcc -O3.
     */
    /* zlib.h -- interface of the 'zlib' general purpose  compression library
       version 1.1.3, July 9th, 1998
       Copyright (C) 1995-1998 Jean-loup Gailly and Mark  Adler
       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
      This email address is being protected from spambots. You need JavaScript enabled to view it.           This email address is being protected from spambots. You need JavaScript enabled to view it.
      
      The data format used by the zlib library is described  by RFCs (Request for
      Comments) 1950 to 1952 in the files  ftp://ds.internic.net/rfc/rfc1950.txt
      (zlib format), rfc1951.txt (deflate format) and  rfc1952.txt (gzip format).
    */
    

    LZMA

    Below are given the license and disclaimer for LZMA.

    LZMA SDK 4.57

    LZMA SDK Copyright (C) 1999-2007 Igor Pavlov

    LZMA SDK provides the documentation, samples, header files, libraries, and tools you need to develop applications that use LZMA compression.

    LZMA is default and general compression method of 7z format in 7-Zip compression program (www.7-zip.org). LZMA provides high compression ratio and very fast decompression.

    LZMA is an improved version of famous LZ77 compression algorithm. It was improved in way of maximum increasing of compression ratio, keeping high decompression speed and low memory requirements for decompressing.

    LICENSE

    LZMA SDK is available under any of the following licenses:

    1. GNU Lesser General Public License (GNU LGPL)
    2. Common Public License (CPL)
    3. Simplified license for unmodified code (read SPECIAL EXCEPTION)
    4. Proprietary license

    It means that you can select one of these four options and follow rules of that license.

    1,2) GNU LGPL and CPL licenses are pretty similar and both these licenses are classified as

    • "Free software licenses" at http://www.gnu.org/
    • "OSI-approved" at http://www.opensource.org/

    3) SPECIAL EXCEPTION

    Igor Pavlov, as the author of this code, expressly permits you to statically or dynamically link your code (or bind by name) to the files from LZMA SDK without subjecting your linked code to the terms of the CPL or GNU LGPL. Any modifications or additions to files from LZMA SDK, however, are subject to the GNU LGPL or CPL terms.

    SPECIAL EXCEPTION allows you to use LZMA SDK in applications with closed code, while you keep LZMA SDK code unmodified.

    SPECIAL EXCEPTION #2: Igor Pavlov, as the author of this code, expressly permits you to use this code under the same terms and conditions contained in the License Agreement you have for any previous version of LZMA SDK developed by Igor Pavlov.

    SPECIAL EXCEPTION #2 allows owners of proprietary licenses to use latest version of LZMA SDK as update for previous versions.

    SPECIAL EXCEPTION #3: Igor Pavlov, as the author of this code, expressly permits you to use code of the following files: BranchTypes.h, LzmaTypes.h, LzmaTest.c, LzmaStateTest.c, LzmaAlone.cpp, LzmaAlone.cs, LzmaAlone.java as public domain code.

    4) Proprietary license

    LZMA SDK also can be available under a proprietary license which can include:

    1. Right to modify code without subjecting modified code to the terms of the CPL or GNU LGPL
    2. Technical support for code

    To request such proprietary license or any additional consultations, send email message from that page: http://www.7-zip.org/support.html

    You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    You should have received a copy of the Common Public License along with this library.


    OpenSSL Public License

    Below are given the license and disclaimer for OpenSSL.

    LICENSE ISSUES

    The OpenSSL toolkit stays under a dual license, i.e. both the conditions of the OpenSSL License and the original SSLeay license apply to the toolkit. See below for the actual license texts. Actually both licenses are BSD-style Open Source licenses. In case of any license issues related to OpenSSL please contact This email address is being protected from spambots. You need JavaScript enabled to view it..

    OpenSSL License

    /* ====================================================================
     * Copyright (c) 1998-2007 The OpenSSL 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. All advertising materials mentioning features or use of this
     *    software must display the following acknowledgment:
     *    "This product includes software developed by the OpenSSL Project
     *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
     *
     * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
     *    endorse or promote products derived from this software without
     *    prior written permission. For written permission, please contact
     *    This email address is being protected from spambots. You need JavaScript enabled to view it..
     *
     * 5. Products derived from this software may not be called "OpenSSL"
     *    nor may "OpenSSL" appear in their names without prior written
     *    permission of the OpenSSL Project.
     *
     * 6. Redistributions of any form whatsoever must retain the following
     *    acknowledgment:
     *    "This product includes software developed by the OpenSSL Project
     *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
     *
     * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
     * EXPRESSED 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 OpenSSL PROJECT OR
     * ITS 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.
     * ====================================================================
     *
     * This product includes cryptographic software written by Eric Young
     * (This email address is being protected from spambots. You need JavaScript enabled to view it.).  This product includes software written by Tim
     * Hudson (This email address is being protected from spambots. You need JavaScript enabled to view it.).
     *
     */
     
     Original SSLeay License
     -----------------------
     
    /* Copyright (C) 1995-1998 Eric Young (This email address is being protected from spambots. You need JavaScript enabled to view it.)
     * All rights reserved.
     *
     * This package is an SSL implementation written
     * by Eric Young (This email address is being protected from spambots. You need JavaScript enabled to view it.).
     * The implementation was written so as to conform with Netscapes SSL.
     *
     * This library is free for commercial and non-commercial use as long as
     * the following conditions are aheared to.  The following conditions
     * apply to all code found in this distribution, be it the RC4, RSA,
     * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
     * included with this distribution is covered by the same copyright terms
     * except that the holder is Tim Hudson (This email address is being protected from spambots. You need JavaScript enabled to view it.).
     *
     * Copyright remains Eric Young's, and as such any Copyright notices in
     * the code are not to be removed.
     * If this package is used in a product, Eric Young should be given attribution
     * as the author of the parts of the library used.
     * This can be in the form of a textual message at program startup or
     * in documentation (online or textual) provided with the package.
     *
     * 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 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 cryptographic software written by
     *     Eric Young (This email address is being protected from spambots. You need JavaScript enabled to view it.)"
     *    The word 'cryptographic' can be left out if the rouines from the library
     *    being used are not cryptographic related :-).
     * 4. If you include any Windows specific code (or a derivative thereof) from
     *    the apps directory (application code) you must include an acknowledgement:
     *    "This product includes software written by Tim Hudson (This email address is being protected from spambots. You need JavaScript enabled to view it.)"
     *
     * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``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 AUTHOR 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.
     *
     * The licence and distribution terms for any publically available version or
     * derivative of this code cannot be changed.  i.e. this code cannot simply be
     * copied and put under another distribution licence
     * [including the GNU Public Licence.]
     */
    

    PPMd

    Below are given the license and disclaimer for PPMd by Dmitry Shkarin.

    3. LEGAL stuff.

    You can not misattribute authorship on algorithm or code sources, You can not patent algorithm or its parts, all other things are allowed and welcomed. Dmitry Subbotin and me have authorship rights on code sources. Dmitry Subbotin owns authorship rights on his variation of rangecoder algorithm and I own authorship rights on my variation of PPM algorithm. This variation is named PPMII (PPM with Information Inheritance).

    PPMonstr program is distributed for experiments and noncommercial use only.


    UnRAR

    Below are given the license and disclaimer for software written by Alexander Roshal for implementing decompression for RAR.

    The source code of UnRAR utility is freeware. This means:

    1. All copyrights to RAR and the utility UnRAR are exclusively owned by the author - Alexander Roshal.
    2. The UnRAR sources may be used in any software to handle RAR archives without limitations free of charge, but cannot be used to re-create the RAR compression algorithm, which is proprietary. Distribution of modified UnRAR sources in separate form or as a part of other software is permitted, provided that it is clearly stated in the documentation and source comments that the code may not be used to develop a RAR (WinRAR) compatible archiver.
    3. The UnRAR utility may be freely distributed. It is allowed to distribute UnRAR inside of other software packages.
    4. THE RAR ARCHIVER AND THE UnRAR UTILITY ARE DISTRIBUTED "AS IS". NO WARRANTY OF ANY KIND IS EXPRESSED OR IMPLIED. YOU USE AT YOUR OWN RISK. THE AUTHOR WILL NOT BE LIABLE FOR DATA LOSS, DAMAGES, LOSS OF PROFITS OR ANY OTHER KIND OF LOSS WHILE USING OR MISUSING THIS SOFTWARE.
    5. Installing and using the UnRAR utility signifies acceptance of< these terms and conditions of the license.
    6. If you don't agree with terms of the license you must remove UnRAR files from your storage devices and cease to use the utility.

 


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Products » ZIP
security

ZIP

What is ZIP? What can ZIP do for me?

ZIP files to save storage space

To put it simply, ZIP allows you to compress files to save storage space. Zipped files take up much less space on hard drives, flash drives, CDs, DVDs, etc.

ZIP files to speed transmission time

If you want to quickly send files, ZIP makes the job much easier. By compressing the file(s), sending information via email, FTP, etc. is that much easier – the smaller the file, the faster it will reach its destination.

How does ZIP work?

When a file is zipped (compressed), all redundant data is replaced by a smaller reference to that data. This allows the file to be reduced in size for easier storage and/or transfer. When that file is unzipped (decompressed), the reference is replaced by the original data so it can once again be read in its original form.

ZIP is lossless

ZIP is a “lossless” form of file compression – this means that none of the original data is ever lost.

.ZIP file format

The ZIP file format is a data compression and archive format. Individual files are compressed to reduce their size and then placed in a ZIP archive. ZIP files are usually labeled with a .zip or .ZIP file extension. ZIP is the most popular file format in the world and is utilized by individual users, businesses, and government agencies to efficiently handle and manage files. The .ZIP Application Note is available here.

Founder of ZIP

PKWARE founder, Phil Katz , invented the .zip file format in 1986. Phil made the .zip file standard an open standard in 1989.

ZIP software from PKWARE

While there are many products available today that will zip a file, PKWARE offers both PKZIP and SecureZIP software. PKZIP and SecureZIP will each compress files up to 95%! In addition to the file compression and management capabilities of PKZIP, SecureZIP offers all of the benefits of PKZIP plus strong encryption to protect sensitive information. To download a free 30-day evaluation of our ZIP products, click here.

Unzip software

After a file is zipped, it must be unzipped to access it. PKZIP and SecureZIP will both unzip as well as zip files. For those who need to unzip and/or decrypt files. but do not need to zip them, PKWARE continues to offer its ZIP Reader  for free. ZIP Reader will not zip files. To download ZIP Reader, click here.

Self-extracting ZIP files

If there is a need for a file that can be unzipped without the use of decompression software, a self-extracting zip file can be created. A self-extracting zip file will have a .exe file extension.


Application Note Archives

This page provides a fixed location for APPNOTE reference and change history.

Specific versions of the APPNOTE named within other published specifications are posted here for reference.

 
6.2.0 – 04/26/2004
This version is provided in support of ECMA-376 and ISO/IEC 29500, the standards for Office Open XML File Formats. These document standards incorporate ZIP technology based on this specification.

To download APPNOTE version 6.2.0, Click Here or copy and paste the following URL into your browser window:
www.pkware.com/documents/APPNOTE/APPNOTE_6.2.0.txt
 


Other Archived Versions:
APPNOTE-6.3.3.TXT
APPNOTE-6.3.0.TXT
APPNOTE-6.2.0.TXT
APPNOTE-5.2.0.TXT
APPNOTE-4.5.0.TXT
APPNOTE-2.0.TXT
APPNOTE-1.0.TXT