type Decrypter interface {
	// Public returns the public key corresponding to the opaque,
	// private key.
	Public() PublicKey

	// Decrypt decrypts msg. The opts argument should be appropriate for
	// the primitive used. See the documentation in each implementation for
	// details.
	Decrypt(rand io.Reader, msg []byte, opts DecrypterOpts) (plaintext []byte, err error)
}

type DecrypterOpts any

type Hash uint

const (
	MD4         Hash = 1 + iota // import golang.org/x/crypto/md4
	MD5                         // import crypto/md5
	SHA1                        // import crypto/sha1
	SHA224                      // import crypto/sha256
	SHA256                      // import crypto/sha256
	SHA384                      // import crypto/sha512
	SHA512                      // import crypto/sha512
	MD5SHA1                     // no implementation; MD5+SHA1 used for TLS RSA
	RIPEMD160                   // import golang.org/x/crypto/ripemd160
	SHA3_224                    // import golang.org/x/crypto/sha3
	SHA3_256                    // import golang.org/x/crypto/sha3
	SHA3_384                    // import golang.org/x/crypto/sha3
	SHA3_512                    // import golang.org/x/crypto/sha3
	SHA512_224                  // import crypto/sha512
	SHA512_256                  // import crypto/sha512
	BLAKE2s_256                 // import golang.org/x/crypto/blake2s
	BLAKE2b_256                 // import golang.org/x/crypto/blake2b
	BLAKE2b_384                 // import golang.org/x/crypto/blake2b
	BLAKE2b_512                 // import golang.org/x/crypto/blake2b

)

type PrivateKey any

type PublicKey any

type Signer interface {
	// Public returns the public key corresponding to the opaque,
	// private key.
	Public() PublicKey

	// Sign signs digest with the private key, possibly using entropy from
	// rand. For an RSA key, the resulting signature should be either a
	// PKCS #1 v1.5 or PSS signature (as indicated by opts). For an (EC)DSA
	// key, it should be a DER-serialised, ASN.1 signature structure.
	//
	// Hash implements the SignerOpts interface and, in most cases, one can
	// simply pass in the hash function used as opts. Sign may also attempt
	// to type assert opts to other types in order to obtain algorithm
	// specific values. See the documentation in each package for details.
	//
	// Note that when a signature of a hash of a larger message is needed,
	// the caller is responsible for hashing the larger message and passing
	// the hash (as digest) and the hash function (as opts) to Sign.
	Sign(rand io.Reader, digest []byte, opts SignerOpts) (signature []byte, err error)
}

type SignerOpts interface {
	// HashFunc returns an identifier for the hash function used to produce
	// the message passed to Signer.Sign, or else zero to indicate that no
	// hashing was done.
	HashFunc() Hash
}