[cm/prv/] with GOST R 34.10-2012.
GOST R 34.10-2012 is signing/key-aggreement algorithm.
=> https://datatracker.ietf.org/doc/html/rfc7091.html RFC 7091, GOST R 34.10-2012
Big-endian private key representation must be used.
Only twisted Edwards curves are used.
Following algorithm identifiers are used: "gost3410-256A", "gost3410-512C".
