func (pk *RsaPublicKey) Encrypt(b []byte) ([]byte, error) {
	return rsa.EncryptPKCS1v15(rand.Reader, pk.k, b)
}
func (pk *RsaPublicKey) Encrypt(b []byte) ([]byte, error) {
	return rsa.EncryptPKCS1v15(rand.Reader, pk.k, b)
}
// Encrypt returns encrypted bytes from the inpu data