code: func New224() hash.Hash {
  	if h := new224Asm(); h != nil {
  		return h
  	}
  	return &state{rate: 144, outputLen: 28, dsbyte: 0x01}
  }
docs: // New224 creates a new SHA3-224 hash.
  // Its generic security strength is 224 bits against preimage attacks,
  // and 112 bits against collision attacks.