CryptoPkg - jljusten/tianocore GitHub Wiki
UEFI details interfaces between the OS and platform firmware. Several security features were introduced (e.g. Authenticated Variable Service, Driver Signing, etc) starting in UEFI Specification version 2.2 (http://www.uefi.org). These security features highly depend on cryptography, which is implemented in EDK II using CryptoPkg.
https://github.com/tianocore/edk2/tree/master/CryptoPkg
https://github.com/tianocore/edk2/raw/master/CryptoPkg/Library/OpensslLib/OpenSSL-HOWTO.txt
For EDK II branches prior to UDK2017 ... There is a dependency on a specific OpenSSL version for your workspace. Please refer to
<YourWorkSpace>/CryptoPkg/Library/OpensslLib/Patch-HOWTO.txtfor information on how to download and apply patches required to compile CryptoPkg.