Custom method functions removed from the OpenSSL Library

Following on from the removal of ENGINE
code, deprecated functions for
creating or modifying custom
METHODS
will be removed from OpenSSL 4.0.

Summary

For a complete list of deprecated functions removed in OpenSSL 4.0,
please see the
ossl-removed-api
documentation. They are divided into the following pull requests:

• Custom ciphers methods (EVP_CIPHER_meth_*) were removed in PR
  #29299.
• Custom message digest methods (EVP_MD_meth_*) were removed in PR
  #29366.
• Custom private key methods (EVP_PKEY_meth_*) were removed in PR
  #29384.
• Custom private key Abstract Syntax Notation
  One methods
  (EVP_PKEY_asn1_*) were removed in PR
  #29405. (These
  functions were deprecated in OpenSSL 3.6.)

Instead of using these methods, developers are encouraged to use the
provider framework.