[Retracted] Enabling Decentralized and Auditable Access Control for IoT through Blockchain and Smart Contracts

Algorithm 1

Policy smart contract.

	contract policy:
	register(domainID, XACMLfile):
	// verify if the policy exists
	if ! exist(hash(XACMLfile)) then
	put(domainID, hash(XACMLfile))
	store(XACMLfile)
	return true
	else
	return false
	end if
	query(domainID):
	policy = get(domainID)
	if error != nil then
	return error
	//error occurred
	else
	return policy
	// hash value of policy returned
	end if
	evaluate(domainID, XACMLrequest):
	policy = get(domainID)
	if error != nil then
	return error
	//error occurred
	else
	response = match(policy, XACMLrequest)
	return response
	end if