private static SECPSignature parseProposerSeal(final RLPInput rlpInput) {
    final Bytes data = rlpInput.readBytes();
    return data.isZero() ? null : SIGNATURE_ALGORITHM.get().decodeSignature(data);
  }
Decode raw input and return ibft extra data.

@param input the input
@return the ibft extra data
consensus/ibftlegacy/src/main/java/org/hyperledger/besu/consensus/ibftlegacy/IbftExtraDataCodec.java