sec1 vs pkcs8 vs pem-rfc7468

Pure Rust implementation of SEC1: Elliptic Curve Cryptography encoding formats including ASN.1 DER-serialized private keys as well as the Elliptic-Curve-Point-to-Octet-String encoding

Pure Rust implementation of Public-Key Cryptography Standards (PKCS) #8: Private-Key Information Syntax Specification (RFC 5208), with additional support for PKCS#8v2 asymmetric key packages (RFC 5958)

PEM Encoding (RFC 7468) for PKIX, PKCS, and CMS Structures, implementing a strict subset of the original Privacy-Enhanced Mail encoding intended specifically for use with cryptographic keys, certificates, and other messages. Provides a no_std-friendly, constant-time implementation suitable for use with cryptographic private keys.