Major changes between OpenSSL 1.1.1 and OpenSSL 3.0.0 [under development]
+ o enable-crypto-mdebug and enable-crypto-mdebug-backtrace were mostly
+ disabled; the project uses address sanitize/leak-detect instead.
+ o Added OSSL_SERIALIZER, a generic serializer API.
o Added error raising macros, ERR_raise() and ERR_raise_data().
o Deprecated ERR_put_error().
o Added OSSL_PROVIDER_available(), to check provider availibility.
o Removed the heartbeat message in DTLS feature.
o Added EVP_KDF, an EVP layer KDF API, and a generic EVP_PKEY to EVP_KDF
bridge.
+ o All of the low level MD2, MD4, MD5, MDC2, RIPEMD160, SHA1, SHA224,
+ SHA256, SHA384, SHA512 and Whirlpool digest functions have been
+ deprecated.
+ o All of the low level AES, Blowfish, Camellia, CAST, DES, IDEA, RC2,
+ RC4, RC5 and SEED cipher functions have been deprecated.
Major changes between OpenSSL 1.1.1 and OpenSSL 1.1.1a [20 Nov 2018]