This file gives a brief overview of the major changes between each OpenSSL release. For more details please read the CHANGES file.
Support for TLSv1.3 added. The TLSv1.3 implementation includes:
Complete rewrite of the OpenSSL random number generator to introduce the following capabilities
Support for various new cryptographic algorithms including:
Significant Side-Channel attack security improvements
Add a new ClientHello callback to provide the ability to adjust the SSL object at an early stage.
Add 'Maximum Fragment Length' TLS extension negotiation and support
A new STORE module, which implements a uniform and URI based reader of stores that can contain keys, certificates, CRLs and numerous other objects.
Move the display of configuration data to configdata.pm.
Allow GNU style "make variables" to be used with Configure.
Claim the namespaces OSSL and OPENSSL, represented as symbol prefixes
Rewrite of devcrypto engine
Known issues in OpenSSL 1.0.0m:
 The support for external crypto devices is currently a separate distribution. See the file README.ENGINE.