The behavior of EVP_PKEY_public_check changed between OpenSSL 1.1.1
and 3.0 so that it no longer validates the private key. Instead, private
keys can be validated through EVP_PKEY_private_check and
EVP_PKEY_pairwise_check.

[ky: simplified condition to use either EVP_PKEY_check() or
EVP_PKEY_public_check().]

https://github.com/ruby/openssl/commit/e38a63ab3d

Systems such as RHEL 9 are moving away from SHA1
disabling it completely in default configuration.

https://github.com/ruby/openssl/commit/32648da2f6

i2d_PUBKEY_bio() against an EC_KEY without the public key component
trggers a null dereference.

This is a regression introduced by commit https://github.com/ruby/openssl/commit/56f0d34d63fb ("pkey:
refactor #export/#to_pem and #to_der", 2017-06-14).

Fixes https://github.com/ruby/openssl/pull/527#issuecomment-1220504524
Fixes https://github.com/ruby/openssl/issues/369#issuecomment-1221554057

https://github.com/ruby/openssl/commit/f6ee0fa4de

Scan through the input for a private key, then fallback to generic
decoder.

OpenSSL 3.0's OSSL_DECODER supports encoded key parameters. The PEM
header "-----BEGIN EC PARAMETERS-----" is used by one of such encoding
formats. While this is useful for OpenSSL::PKey::PKey, an edge case has
been discovered.

The openssl CLI command line "openssl ecparam -genkey" prints two PEM
blocks in a row, one for EC parameters and another for the private key.
Feeding the whole output into OSSL_DECODER results in only the first PEM
block, the key parameters, being decoded. Previously, ruby/openssl did
not support decoding key parameters and it would decode the private key
PEM block instead.

While the new behavior is technically correct, "openssl ecparam -genkey"
is so widely used that ruby/openssl does not want to break existing
applications.

Fixes https://github.com/ruby/openssl/pull/535

https://github.com/ruby/openssl/commit/d486c82833

OpenSSL 3.0 made EVP_PKEY immutable. This means we can only have a const
pointer of the low level struct and the following methods can no longer
be provided when linked against OpenSSL 3.0:

 - OpenSSL::PKey::RSA#set_key
 - OpenSSL::PKey::RSA#set_factors
 - OpenSSL::PKey::RSA#set_crt_params
 - OpenSSL::PKey::DSA#set_pqg
 - OpenSSL::PKey::DSA#set_key
 - OpenSSL::PKey::DH#set_pqg
 - OpenSSL::PKey::DH#set_key
 - OpenSSL::PKey::EC#group=
 - OpenSSL::PKey::EC#private_key=
 - OpenSSL::PKey::EC#public_key=

There is no direct replacement for this functionality at the moment.
I plan to introduce a wrapper around EVP_PKEY_fromdata(), which takes
all key components at once to construct an EVP_PKEY.

https://github.com/ruby/openssl/commit/6848d2d969

OpenSSL::PKey::EC#generate_key! will not work on OpenSSL 3.0 because
keys are made immutable. Users should use OpenSSL::PKey.generate_key
instead.

https://github.com/ruby/openssl/commit/5e2e66cce8

Disabling ECC support of OpenSSL is impractical nowadays.

We still try to have the C extension compile on no-ec builds (as well
as no-dh or no-engine, etc.) as long as we can, but keeping test cases
for such an extreme scenario is not worth the effort.

https://github.com/ruby/openssl/commit/2cd01d4676

It uses deprecated PKey::{RSA,DSA,DH}#set_* methods, which will not
work with OpenSSL 3.0. The same can easily be achieved using
PKey#public_to_der regardless of the key kind.

https://github.com/ruby/openssl/commit/7b66eaa2db

Add a variant of PKey#sign and #verify that do not hash the data
automatically.

Sometimes the caller has the hashed data only, but not the plaintext
to be signed. In that case, users would have to use the low-level API
such as RSA#private_encrypt or #public_decrypt directly.

OpenSSL 1.0.0 and later supports EVP_PKEY_sign() and EVP_PKEY_verify()
which provide the same functionality as part of the EVP API. This patch
adds wrappers for them.

https://github.com/ruby/openssl/commit/16cca4e0c4

Deprecate it for future removal. However, I do not expect any
application is affected by this.

The other form of calling it, PKey::EC::Point#mul(bn [, bn]) remains
untouched.

PKey::EC::Point#mul calls EC_POINTs_mul(3) when multiple BNs
are given as an array. LibreSSL 2.8.0 released on 2018-08 removed the
feature and OpenSSL 3.0 which is planned to be released in 2020 will
also deprecate the function as there is no real use-case.

https://github.com/ruby/openssl/commit/812de4253d