code: func (u *utils) DecryptPEMBlock(block *pem.Block, password []byte) ([]byte, error) {
  	if IsPKCS8(block.Bytes) {
  		return pkcs8.DecryptPEMBlock(block, password)
  	} else if u.fips {
  		return nil, ErrFIPSUnsupportedKeyFormat
  	}
  
  	return x509.DecryptPEMBlock(block, password)
  }
docs: // DecryptPEMBlock requires PKCS#1 or PKCS#8 PEM Block and password to decrypt and return unencrypted der []byte
  // It returns an error in FIPS mode when PKCS#1 PEM Block is passed.