openssl_sign()'s new $padding parameter needs to be OPENSSL_PKCS1_PSS_PADDING for PSS padding to work

[terrafrost]

Per https://www.php.net/manual/en/function.openssl-sign.php PHP 8.5.0 saw the addition of a new parameter to openssl_sign() - $padding. The documentation says, simply, "RSA PSS padding to use". From that one might think simply setting $padding to 1 would be sufficient but it isn't - it needs to be OPENSSL_PKCS1_PSS_PADDING for PSS signatures to work.

That said, OPENSSL_PKCS1_PSS_PADDING does not appear to be mentioned anywhere else. https://www.php.net/manual/en/openssl.padding.php doesn't seem appropriate because that's "Padding flags for asymmetric encryption". For that I suppose there are two things that could be done. Either that could be renamed "Padding flags" or a whole new page - "Padding flags for signatures" - could be created. I suppose a third option would be to add OPENSSL_PKCS1_PSS_PADDING to https://www.php.net/manual/en/openssl.constants.other.php . That page already has OPENSSL_ZERO_PADDING after all...