Go to file
2021-08-18 08:38:40 +10:00
.github CI: remove spurious blank lines 2021-08-05 15:41:29 +10:00
apps Disclaimer about the default provider activation added to config 2021-08-12 09:59:34 +02:00
Configurations
crypto s390x: AES OFB/CFB: Maintain running IV from cipher context 2021-08-16 13:02:50 +02:00
demos
dev
doc Correct UTF8 params documentation further 2021-08-17 13:50:18 +02:00
engines
external/perl
fuzz
gost-engine@62583fb222
include aes_v8_xts_encrypt is present only on 64bit arm builds 2021-08-11 10:08:57 +02:00
krb5@aa9b4a2a64
ms
os-dep
providers Refactor cipher aes_cts code so that it can be used by other 128bit ciphers 2021-08-18 08:38:40 +10:00
pyca-cryptography@0034926f2c
ssl Fix potential double-free 2021-08-16 12:56:53 +02:00
test Test EVP Cipher updating the context's IV 2021-08-16 13:02:51 +02:00
tools
util
VMS
wycheproof@2196000605
.gitattributes
.gitignore
.gitmodules
ACKNOWLEDGEMENTS.md
appveyor.yml
AUTHORS.md
build.info
CHANGES.md Add documentation about the multilib postfix and libdir 2021-08-13 10:45:44 +02:00
config
config.com
configdata.pm.in
Configure
CONTRIBUTING.md
e_os.h
FAQ.md
HACKING.md
INSTALL.md Add documentation about the multilib postfix and libdir 2021-08-13 10:45:44 +02:00
LICENSE.txt
NEWS.md
NOTES-ANDROID.md
NOTES-DJGPP.md
NOTES-NONSTOP.md
NOTES-PERL.md
NOTES-UNIX.md
NOTES-VALGRIND.md
NOTES-VMS.md
NOTES-WINDOWS.md
README-ENGINES.md
README-FIPS.md
README-PROVIDERS.md
README.md
SUPPORT.md
VERSION.dat

Welcome to the OpenSSL Project

openssl logo

github actions ci badge appveyor badge

OpenSSL is a robust, commercial-grade, full-featured Open Source Toolkit for the Transport Layer Security (TLS) protocol formerly known as the Secure Sockets Layer (SSL) protocol. The protocol implementation is based on a full-strength general purpose cryptographic library, which can also be used stand-alone.

OpenSSL is descended from the SSLeay library developed by Eric A. Young and Tim J. Hudson.

The official Home Page of the OpenSSL Project is www.openssl.org.

Table of Contents

Overview

The OpenSSL toolkit includes:

  • libssl an implementation of all TLS protocol versions up to TLSv1.3 (RFC 8446).

  • libcrypto a full-strength general purpose cryptographic library. It constitutes the basis of the TLS implementation, but can also be used independently.

  • openssl the OpenSSL command line tool, a swiss army knife for cryptographic tasks, testing and analyzing. It can be used for

    • creation of key parameters
    • creation of X.509 certificates, CSRs and CRLs
    • calculation of message digests
    • encryption and decryption
    • SSL/TLS client and server tests
    • handling of S/MIME signed or encrypted mail
    • and more...

Download

For Production Use

Source code tarballs of the official releases can be downloaded from www.openssl.org/source. The OpenSSL project does not distribute the toolkit in binary form.

However, for a large variety of operating systems precompiled versions of the OpenSSL toolkit are available. In particular on Linux and other Unix operating systems it is normally recommended to link against the precompiled shared libraries provided by the distributor or vendor.

For Testing and Development

Although testing and development could in theory also be done using the source tarballs, having a local copy of the git repository with the entire project history gives you much more insight into the code base.

The official OpenSSL Git Repository is located at git.openssl.org. There is a GitHub mirror of the repository at github.com/openssl/openssl, which is updated automatically from the former on every commit.

A local copy of the Git Repository can be obtained by cloning it from the original OpenSSL repository using

git clone git://git.openssl.org/openssl.git

or from the GitHub mirror using

git clone https://github.com/openssl/openssl.git

If you intend to contribute to OpenSSL, either to fix bugs or contribute new features, you need to fork the OpenSSL repository openssl/openssl on GitHub and clone your public fork instead.

git clone https://github.com/yourname/openssl.git

This is necessary, because all development of OpenSSL nowadays is done via GitHub pull requests. For more details, see Contributing.

Build and Install

After obtaining the Source, have a look at the INSTALL file for detailed instructions about building and installing OpenSSL. For some platforms, the installation instructions are amended by a platform specific document.

Specific notes on upgrading to OpenSSL 3.0 from previous versions, as well as known issues are available on the OpenSSL 3.0 Wiki page.

Documentation

Manual Pages

The manual pages for the master branch and all current stable releases are available online.

Wiki

There is a Wiki at wiki.openssl.org which is currently not very active. It contains a lot of useful information, not all of which is up to date.

License

OpenSSL is licensed under the Apache License 2.0, which means that you are free to get and use it for commercial and non-commercial purposes as long as you fulfill its conditions.

See the LICENSE.txt file for more details.

Support

There are various ways to get in touch. The correct channel depends on your requirement. see the SUPPORT file for more details.

Contributing

If you are interested and willing to contribute to the OpenSSL project, please take a look at the CONTRIBUTING file.

Legalities

A number of nations restrict the use or export of cryptography. If you are potentially subject to such restrictions you should seek legal advice before attempting to develop or distribute cryptographic code.

Copyright

Copyright (c) 1998-2021 The OpenSSL Project

Copyright (c) 1995-1998 Eric A. Young, Tim J. Hudson

All rights reserved.