1Welcome to the OpenSSL Project 2============================== 3 4[![openssl logo]][www.openssl.org] 5 6[![github actions ci badge]][github actions ci] 7[![appveyor badge]][appveyor jobs] 8 9OpenSSL is a robust, commercial-grade, full-featured Open Source Toolkit 10for the Transport Layer Security (TLS) protocol formerly known as the 11Secure Sockets Layer (SSL) protocol. The protocol implementation is based 12on a full-strength general purpose cryptographic library, which can also 13be used stand-alone. 14 15OpenSSL is descended from the SSLeay library developed by Eric A. Young 16and Tim J. Hudson. 17 18The official Home Page of the OpenSSL Project is [www.openssl.org]. 19 20Table of Contents 21================= 22 23 - [Overview](#overview) 24 - [Download](#download) 25 - [Build and Install](#build-and-install) 26 - [Documentation](#documentation) 27 - [License](#license) 28 - [Support](#support) 29 - [Contributing](#contributing) 30 - [Legalities](#legalities) 31 32Overview 33======== 34 35The OpenSSL toolkit includes: 36 37- **libssl** 38 an implementation of all TLS protocol versions up to TLSv1.3 ([RFC 8446]). 39 40- **libcrypto** 41 a full-strength general purpose cryptographic library. It constitutes the 42 basis of the TLS implementation, but can also be used independently. 43 44- **openssl** 45 the OpenSSL command line tool, a swiss army knife for cryptographic tasks, 46 testing and analyzing. It can be used for 47 - creation of key parameters 48 - creation of X.509 certificates, CSRs and CRLs 49 - calculation of message digests 50 - encryption and decryption 51 - SSL/TLS client and server tests 52 - handling of S/MIME signed or encrypted mail 53 - and more... 54 55Download 56======== 57 58For Production Use 59------------------ 60 61Source code tarballs of the official releases can be downloaded from 62[www.openssl.org/source](https://www.openssl.org/source). 63The OpenSSL project does not distribute the toolkit in binary form. 64 65However, for a large variety of operating systems precompiled versions 66of the OpenSSL toolkit are available. In particular on Linux and other 67Unix operating systems it is normally recommended to link against the 68precompiled shared libraries provided by the distributor or vendor. 69 70For Testing and Development 71--------------------------- 72 73Although testing and development could in theory also be done using 74the source tarballs, having a local copy of the git repository with 75the entire project history gives you much more insight into the 76code base. 77 78The official OpenSSL Git Repository is located at [git.openssl.org]. 79There is a GitHub mirror of the repository at [github.com/openssl/openssl], 80which is updated automatically from the former on every commit. 81 82A local copy of the Git Repository can be obtained by cloning it from 83the original OpenSSL repository using 84 85 git clone git://git.openssl.org/openssl.git 86 87or from the GitHub mirror using 88 89 git clone https://github.com/openssl/openssl.git 90 91If you intend to contribute to OpenSSL, either to fix bugs or contribute 92new features, you need to fork the OpenSSL repository openssl/openssl on 93GitHub and clone your public fork instead. 94 95 git clone https://github.com/yourname/openssl.git 96 97This is necessary, because all development of OpenSSL nowadays is done via 98GitHub pull requests. For more details, see [Contributing](#contributing). 99 100Build and Install 101================= 102 103After obtaining the Source, have a look at the [INSTALL](INSTALL.md) file for 104detailed instructions about building and installing OpenSSL. For some 105platforms, the installation instructions are amended by a platform specific 106document. 107 108 * [Notes for UNIX-like platforms](NOTES-UNIX.md) 109 * [Notes for Android platforms](NOTES-ANDROID.md) 110 * [Notes for Windows platforms](NOTES-WINDOWS.md) 111 * [Notes for the DOS platform with DJGPP](NOTES-DJGPP.md) 112 * [Notes for the OpenVMS platform](NOTES-VMS.md) 113 * [Notes on Perl](NOTES-PERL.md) 114 * [Notes on Valgrind](NOTES-VALGRIND.md) 115 116Specific notes on upgrading to OpenSSL 3.0 from previous versions can be found 117in the [migration_guide(7ossl)] manual page. 118 119Documentation 120============= 121 122Manual Pages 123------------ 124 125The manual pages for the master branch and all current stable releases are 126available online. 127 128- [OpenSSL master](https://www.openssl.org/docs/manmaster) 129- [OpenSSL 3.0](https://www.openssl.org/docs/man3.0) 130- [OpenSSL 1.1.1](https://www.openssl.org/docs/man1.1.1) 131 132Wiki 133---- 134 135There is a Wiki at [wiki.openssl.org] which is currently not very active. 136It contains a lot of useful information, not all of which is up to date. 137 138License 139======= 140 141OpenSSL is licensed under the Apache License 2.0, which means that 142you are free to get and use it for commercial and non-commercial 143purposes as long as you fulfill its conditions. 144 145See the [LICENSE.txt](LICENSE.txt) file for more details. 146 147Support 148======= 149 150There are various ways to get in touch. The correct channel depends on 151your requirement. see the [SUPPORT](SUPPORT.md) file for more details. 152 153Contributing 154============ 155 156If you are interested and willing to contribute to the OpenSSL project, 157please take a look at the [CONTRIBUTING](CONTRIBUTING.md) file. 158 159Legalities 160========== 161 162A number of nations restrict the use or export of cryptography. If you are 163potentially subject to such restrictions you should seek legal advice before 164attempting to develop or distribute cryptographic code. 165 166Copyright 167========= 168 169Copyright (c) 1998-2024 The OpenSSL Project 170 171Copyright (c) 1995-1998 Eric A. Young, Tim J. Hudson 172 173All rights reserved. 174 175<!-- Links --> 176 177[www.openssl.org]: 178 <https://www.openssl.org> 179 "OpenSSL Homepage" 180 181[git.openssl.org]: 182 <https://git.openssl.org> 183 "OpenSSL Git Repository" 184 185[git.openssl.org]: 186 <https://git.openssl.org> 187 "OpenSSL Git Repository" 188 189[github.com/openssl/openssl]: 190 <https://github.com/openssl/openssl> 191 "OpenSSL GitHub Mirror" 192 193[wiki.openssl.org]: 194 <https://wiki.openssl.org> 195 "OpenSSL Wiki" 196 197[migration_guide(7ossl)]: 198 <https://www.openssl.org/docs/man3.0/man7/migration_guide.html> 199 "OpenSSL Migration Guide" 200 201[RFC 8446]: 202 <https://tools.ietf.org/html/rfc8446> 203 204<!-- Logos and Badges --> 205 206[openssl logo]: 207 doc/images/openssl.svg 208 "OpenSSL Logo" 209 210[github actions ci badge]: 211 <https://github.com/openssl/openssl/workflows/GitHub%20CI/badge.svg> 212 "GitHub Actions CI Status" 213 214[github actions ci]: 215 <https://github.com/openssl/openssl/actions?query=workflow%3A%22GitHub+CI%22> 216 "GitHub Actions CI" 217 218[appveyor badge]: 219 <https://ci.appveyor.com/api/projects/status/8e10o7xfrg73v98f/branch/master?svg=true> 220 "AppVeyor Build Status" 221 222[appveyor jobs]: 223 <https://ci.appveyor.com/project/openssl/openssl/branch/master> 224 "AppVeyor Jobs" 225