ethereum private chain anchoring

privatechain.sol

pragma solidity ^0.4.18;

contract PrivateChain {
 struct BLOCK {
     address miner;
     address validator;
     uint time;
     uint txListHash;
 }

 enum NewBlockStatus {NONE, WAIT_FOR_VALIDATION}

 address[] public participants;
 BLOCK[] public blocks;

 NewBlockStatus public status;
 BLOCK public candidate;

 uint public currentMiner = 0;
 
 function PrivateChain () public {
     status = NewBlockStatus.NONE;
     participants.push(msg.sender);
 }
 
 function addBlockCandidate(uint txListHash) public {
     assert(status == NewBlockStatus.NONE);
     assert(msg.sender == participants[currentMiner]);
 
     status = NewBlockStatus.WAIT_FOR_VALIDATION;
     candidate.miner = msg.sender;
     candidate.time = now;
     candidate.txListHash = txListHash;
 }

 function confirmBlock(uint expectedTxListHash) public {
     assert(status == NewBlockStatus.WAIT_FOR_VALIDATION);
     assert(msg.sender == participants[(currentMiner + 1) % participants.length]);
     assert(candidate.txListHash == expectedTxListHash);
 
     candidate.validator = msg.sender;
 
     blocks.push(candidate);
 
     status = NewBlockStatus.NONE;
     currentMiner = (currentMiner + 1) % participants.length;
 }
}