1 [![openssl logo][]][www.openssl.org]
3 [![travis badge][]][travis jobs]
4 [![appveyor badge][]][appveyor jobs]
8 Welcome to the OpenSSL Project
9 ==============================
11 OpenSSL is a robust, commercial-grade, full-featured Open Source Toolkit
12 for the Transport Layer Security (TLS) protocol formerly known as the
13 Secure Sockets Layer (SSL) protocol. The protocol implementation is based
14 on a full-strength general purpose cryptographic library, which can also
17 OpenSSL is descended from the SSLeay library developed by Eric A. Young
20 The official Home Page of the OpenSSL Project is [www.openssl.org][].
26 - [Overview](#overview)
27 - [Download](#download)
28 - [Build and Install](#build-and-install)
29 - [Documentation](#documentation)
32 - [Contributing](#contributing)
33 - [Legalities](#legalities)
38 The OpenSSL toolkit includes:
41 an implementation of all TLS protocol versions up to TLSv1.3 ([RFC 8446][]).
44 a full-strength general purpose cryptographic library. It constitutes the
45 basis of the TLS implementation, but can also be used independently.
48 the OpenSSL command line tool, a swiss army knife for cryptographic tasks,
49 testing and analyzing. It can be used for
50 - creation of key parameters
51 - creation of X.509 certificates, CSRs and CRLs
52 - calculation of message digests
53 - encryption and decryption
54 - SSL/TLS client and server tests
55 - handling of S/MIME signed or encrypted mail
64 Source code tarballs of the official releases can be downloaded from
65 [www.openssl.org/source](https://www.openssl.org/source).
66 The OpenSSL project does not distribute the toolkit in binary form.
68 However, for a large variety of operating systems precompiled versions
69 of the OpenSSL toolkit are available. In particular on Linux and other
70 Unix operating systems it is normally recommended to link against the
71 precompiled shared libraries provided by the distributor or vendor.
74 For Testing and Development
75 ---------------------------
77 Although testing and development could in theory also be done using
78 the source tarballs, having a local copy of the git repository with
79 the entire project history gives you much more insight into the
82 The official OpenSSL Git Repository is located at [git.openssl.org][].
83 There is a GitHub mirror of the repository at [github.com/openssl/openssl][],
84 which is updated automatically from the former on every commit.
86 A local copy of the Git Repository can be obtained by cloning it from
87 the original OpenSSL repository using
89 git clone git://git.openssl.org/openssl.git
91 or from the GitHub mirror using
93 git clone https://github.com/openssl/openssl.git
95 If you intend to contribute to OpenSSL, either to fix bugs or contribute
96 new features, you need to fork the OpenSSL repository openssl/openssl on
97 GitHub and clone your public fork instead.
99 git clone https://github.com/yourname/openssl.git
101 This is necessary, because all development of OpenSSL nowadays is done via
102 GitHub pull requests. For more details, see [Contributing](#contributing).
108 After obtaining the Source, have a look at the [INSTALL](INSTALL.md) file for
109 detailed instructions about building and installing OpenSSL. For some
110 platforms, the installation instructions are amended by a platform specific
113 * [NOTES.ANDROID](NOTES.ANDROID)
114 * [NOTES.DJGPP](NOTES.DJGPP)
115 * [NOTES.PERL](NOTES.PERL)
116 * [NOTES.UNIX](NOTES.UNIX)
117 * [NOTES.VALGRIND](NOTES.VALGRIND)
118 * [NOTES.VMS](NOTES.VMS)
119 * [NOTES.WIN](NOTES.WIN)
121 Specific notes on upgrading to OpenSSL 3.0 from previous versions, as well as
122 known issues are available on the OpenSSL
123 [wiki](https://wiki.openssl.org/index.php/OpenSSL_3.0).
131 The manual pages for the master branch and all current stable releases are
134 - [OpenSSL master](https://www.openssl.org/docs/manmaster)
135 - [OpenSSL 1.1.1](https://www.openssl.org/docs/man1.1.1)
140 There is a Wiki at [wiki.openssl.org][] which is currently not very active.
141 It contains a lot of useful information, not all of which is up to date.
146 OpenSSL is licensed under the Apache License 2.0, which means that
147 you are free to get and use it for commercial and non-commercial
148 purposes as long as you fulfill its conditions.
150 See the [LICENSE](LICENSE) file for more details.
155 There are various ways to get in touch. The correct channel depends on
156 your requirement. see the [SUPPORT](SUPPORT.md) file for more details.
161 If you are interested and willing to contribute to the OpenSSL project,
162 please take a look at the [CONTRIBUTING](CONTRIBUTING.md) file.
164 Since 2016, development takes place in public on the GitHub open source
165 platform. The OpenSSL Project Pages at [openssl.github.io][] are a
166 valuable source of information if you want to get familiar with our
167 development process on GitHub.
173 A number of nations restrict the use or export of cryptography. If you are
174 potentially subject to such restrictions you should seek legal advice before
175 attempting to develop or distribute cryptographic code.
181 Copyright (c) 1998-2020 The OpenSSL Project
183 Copyright (c) 1995-1998 Eric A. Young, Tim J. Hudson
191 https://www.openssl.org
195 https://git.openssl.org
196 "OpenSSL Git Repository"
199 https://git.openssl.org
200 "OpenSSL Git Repository"
202 [github.com/openssl/openssl]:
203 https://github.com/openssl/openssl
204 "OpenSSL GitHub Mirror"
207 https://mspncp.github.io
208 "OpenSSL Project Pages"
211 https://wiki.openssl.org
216 https://tools.ietf.org/html/rfc8446
219 <!-- Logos and Badges -->
221 Note: The security token for the appveyor badge (the random number in
222 the URL below) was obtained for the mspncp/openssl project.
223 It needs to be replaced by the correct token by some core member
224 (@levitte, @mattcaswell?). It can be obtained for project members at
225 https://ci.appveyor.com/project/openssl/openssl/settings/badges.
229 doc/images/openssl.svg
233 https://travis-ci.org/openssl/openssl.svg?branch=master
234 "Travis Build Status"
237 https://travis-ci.org/openssl/openssl
241 https://ci.appveyor.com/api/projects/status/ikn2l4u1xsume63u/branch/master?svg=true
242 "AppVeyor Build Status"
245 https://ci.appveyor.com/project/openssl/openssl/branch/master