Package: cic-contracts
Smart contract interfacesTechnologyCIC smart contracts are implemented using thesolidityprogramming
language for the (Ethereum Virtual Machine (EVM).Adopted standardsSigningERC - Direct useThe following well-known solidity interfaces are used directly.ERC20 - Token StandardERC165 - Standard Interface
DetectionERC173 - Contract Ownership
StandardERC191 - Signed Data
StandardERC712 - Typed structured data hashing and
signingERC721 - Non-Fungible Token
StandardERC5007 - Time NFT (EIP-721 Time
Extension)ERC5192 - Minimal Soulbound
NFTsERCs Partial useThe following well-known solidity interfaces are partially implemented
in CIC native interfaces.ERC5679 - Token Minting and
Burning(SeeMinter,Burner)Native interfacesAccounts IndexAppend-only list of addresses. Typically used for access control lists.Addresses may beadded,removed, aswell asdeactivatedandactivated. Deactivated accounts still count towards theentryCount.Theentrymethod is used to iterate the account list. The order of
which accounts are returned is not guaranteed. Any returned value
matchingaddress(0x00)should be skipped, and not counted towardsentryCount.May optionally record time when account was added.ERC165 Interface identifierb7bca625Solidity interface definitioninterface IAccountsIndex {
// Address added to store, index in array.
event AddressAdded(uint256 indexed _idx, address _account);// Return number of entries in index.
    function entryCount() external view returns (uint256);

    // Return entry at the spceificed index.
    // Will revert if index is beyond array length.
    // An entry result of 0 means the entry should be skipped, and not count towards entry count.
    function entry(uint256) external view returns (address);

    // Add an entry to the index. Incresases the entry count.
    function add(address) external returns (bool);

    // Verify that the entry exists in the index.
    function have(address) external view returns (bool);

    // Retrieve the timestamp when account was added.
    // If time is not being tracked, a value of 0 should be returned.
    function time(address) external view returns (uint256);
}Reference implementationgit://holbrook.no/eth-accounts-index.git(v0.5.1)Accounts Index MutableExtends the functionality ofAccounts Indexto allow changes to the
address list.Addresses may beadded,removed, aswell asdeactivatedandactivated. Deactivated accounts still count towards theentryCount.ERC165 Interface identifier9479f0aeSolidity interface definitioninterface IAccountsIndexMutable {
// Active status of address changed, and by whom changed.
event AddressActive(address indexed _account, bool _active);// Address removed from store, and by whom removed.
    event AddressRemoved(address _account);

    // Remove an entry from the index. Reduces the entry count.
    function remove(address) external returns (bool);

    // Deactivate account but keep in index. Does not affect entry count.
    function deactivate(address) external returns (bool);

    // Activate previously deactivated account. Does not affect entry count.
    function activate(address) external returns (bool);

    // Check if account exists and is active;
    function isActive(address) external view returns (bool);
}Reference implementationgit://holbrook.no/eth-accounts-index.git(v0.5.1)BurnerAttached toERC20andERC721tokens that may beburned.Implements theburn(...)part ofERC5679for interoperability.ERC165 Interface identifierbc4babddSolidity interface definitioninterface IBurner {
// Token(s) successfully burned; by who and how much.
event Burn(address indexed _burner, uint256 _burned);// Satisfies ERC 5679
    function burn(address _from, uint256 _amount, bytes calldata _data) external;

    // Burn given amount of tokens held by signer.
    function burn(uint256 _burn) external returns (bool);

    // Burn all tokens held by signer.
    function burn() external returns (bool);

    // Total amount of tokens that have been burned.
    function totalBurned() external returns (uint256);

    // Total amount of tokens ever minted.
    // If totalSupply() is available (ERC20, ERC721 Enumerable), this equals totalSupply() + totalBurned().
    function totalMinted() external returns (uint256);
}Example implementationhttps://git.grassecon.net/cicnet/erc20-demurrage-token.gitChronoDefine a creation time for a resource.ComplementsERC5007.ERC165 Interface identifier4db1ccd4Solidity interface definitioninterface IChrono {
// Returns the timestamp of when a resource corresponding to _idx was first created.
// int64 chosen as return value for simpler interoperability with ERC5007.
function createTime(uint256 _idx) external returns(int64);
}Example implementationhttps://git.defalsify.org/eth-erc721(BadgeToken contract)DeclaratorPermissionless store of signed claims made by an address about other
addresses, or addresses about themselves.It is used to declare or respond to certifications of vouchers, NFT,
voucher members.Addresses may be Externally Owned Accounts or smart contracts.Claims may be made with or without topics. A missing topic is synonymous
with a topic value ofbytes32(0x00).Any number of claims can be made about an address under any number of
topics. All claims must be stored, and returned in the order which they
were added.ERC165 Interface identifier21b7493bSolidity interface definitioninterface IDeclarator {
event DeclarationAdded(address indexed _declarator, address indexed _subject, bytes32 indexed _topic, bytes32 _proof);// Get all declarations for a subject (without topic) signed by a declarator
    function declaration(address _declarator, address _subject) external view returns ( bytes32[] memory );

    // Get all declarations for a subject for the given topic signed by a declarator
    function declaration(address _declarator, address _subject, bytes32 _topic) external view returns ( bytes32[] memory );

    // Get number of declarations the declarator has ever signed
    function declarationCount(address _declarator) external view returns ( uint256 );

    // Get the subject of a declarator's declarations at the specific index
    function declarationAddressAt(address _declarator, uint256 _idx) external view returns ( address );

    // Add a declaration for the subject
    function addDeclaration(address _subject, bytes32 _proof) external returns ( bool );

    // Add a declaration with topic for the subject
    function addDeclaration(address _subject, bytes32 _proof, bytes32 _topic) external returns ( bool );

    // Get the declarator that signed a declaration at the specificed index for a subject
    function declaratorAddressAt(address _subject, uint256 _idx) external view returns ( address );

    // Get the number of declarators that have signed for a subject
    function declaratorCount(address _subject) external view returns ( uint256 );
}Reference implementationgit://holbrook.no/eth-address-index.gitDigestAllows encoding of digests according to a specific encoding scheme.Primary use-case is the abstraction of self-describingMulthashencoding.A default encodingmustalways be defined, and the encoding of a valid
digestmustsucceed with the default encoding.ERC165 Interface identifier982ab05dSolidity interface definitioninterface IDigest {
// Returns the default digest encoding used by the contract instance.
function defaultDigestEncoding() external view returns (uint256 _encoding);// Check if the given encoding has been implemented in the contract instance.
    function haveDigestEncoding(uint256 _codec) external view returns(bool);

    // Verify and encode the given digest for a specific hashing algorithm.
    // Returns a zero-length byte array if digest is invalid.
    // Must succeed if called with the defaultDigestEncoding and a valid digest.
    function encodeDigest(bytes memory _data, uint256 _encoding) external view returns (bytes memory);

    // Encodes the digest using the default digest encoding.
    // Returns a zero-length byte array if digest is invalid.
    // Must succeed with a valid digest.
    function encodeDigest(bytes memory _data) external view returns (bytes memory);
}Example implementationgit://holbrook.no/eth-event-msg.gitExpireDefines an expiry time after which token balances or supplycannot
change.A contract defining an expirymust notallow changing the expiration
time to a time in the past.ERC165 Interface identifier841a0e94Solidity interface definitioninterface IExpire {
// Contract has expired.
event Expired(uint256 _timestamp);// Expiry time has changed.
    event ExpiryChange(uint256 indexed _oldTimestamp, uint256 _newTimestamp);

    // The current expiration timestamp.
    function expires() external returns (uint256);

    // Check expiry and apply expiration if expired.
    // Return values must be:
    // 0: not yet expired.
    // 1: already expired.
    // >1: expiry executed.
    function applyExpiry() external returns(uint8);
}Example implementationhttps://git.grassecon.net/cicnet/erc20-demurrage-token.gitFaucetUsed for dispensing tokens to any address.It can be used for gas tokens andERC20alike.The interface is the same whether the faucet is dispensing from existing
balance or minting new tokens.The value dispersedmustbe the same for all addresses.In general, four criteria are expected to exist in any combination for
limiting access to the faucet:TimeA recipient may only use the faucet again after some time has passed.Balance thresholdA recipient may only use the faucet after its balance is below a certain
amount.MembershipA recipient may only use the faucet if it has been added to an access
control list.CapacityThe contract has sufficient token funds to dispense the current defined
amount to dispense.Thecheck(address)contract callmustevaluate all four criteria,
andmustreturnfalseif any of the criteria are not met.ERC165 Interface identifier1a3ac634Solidity interface definitioninterface IFaucet {
// Tokens were given to an address
event Give(address indexed _recipient, address indexed _token, uint256 _value);// The amount that the faucet disperses has changed
    event FaucetAmountChange(uint256 _value);

    // Address of token the faucet represents
    // The faucet will return gas tokens with the zero-address is returned.
    function token() external returns (address);

    // Amount of tokens the faucet gives out
    function tokenAmount() external returns (uint256);

    // Give tokens to the given recipient. Returns amount of tokens given.
    function giveTo(address _recipient) external returns (uint256);

    // Give tokens to yourself. Returns amount of tokens given.
    function gimme() external returns (uint256);

    // Check if faucet may be used in the current contract state by _recipient
    function check(address _recipient) external view returns (bool);

    // Returns timestamp when faucet may be used again by _recipient
    // If 0 is returned, the address has not yet been used.
    // A return value of max(uint256) indicates that the faucet may not be used again.
    function nextTime(address _recipient) external returns (uint256);

    // Returns the token balance under which faucet may be used again by _recipient
    // A return value of max(uint256) indicates that the faucet may be used regardless
    //   of the token balance of _recipient
    function nextBalance(address _recipient) external returns (uint256);
}Reference implementationsgit://holbrook.no/erc20-faucet.gitgit://holbrook.no/eth-faucet.gitLocatorThis interface supportsERC721 Metadata, in particular thetokenURI(uint256)call.Off-chain resources in the CIC networkmustbe defined in terms of
content addressed strings.Itmustbe possible to refer to all off-chain resources directly by
the content address.Furthermore, itshouldbe possible to refer to a resource by a
fully-qualified location on the web or an overlay network (e.g. tor).ERC165 Interface identifiered75b333Solidity interface definitioninterface ILocator {
// URI that may or may not point to a specific resource location.
function toURI(bytes memory _data) external view returns (string memory);// URL pointing to a specific resource location.
    function toURL(bytes memory _data) external view returns(string memory);
}Example implementationgit://holbrook.no/eth-event-msg.gitExpressing locators in terms of numetic token idGiven the numeric token id1234567890987654321(0x112210f4b16c1cb1hex), and a base urlhttps://contentgateway.grassecon.net, the result
of the methods may be as follows:toURI(toHex(1234567890987654321))->https://contentgateway.grassecon.net/000000000000000000000000000000000000000000000000112210f4b16c1cb1toURL(toHex(1234567890987654321))->https://contentgateway.grassecon.net/000000000000000000000000000000000000000000000000112210f4b16c1cb1tokenURI(1234567890987654321)->https://contentgateway.grassecon.net/000000000000000000000000000000000000000000000000112210f4b16c1cb1Expressing locators in terms of a digestGiven the datafoo, the digest algorithmsha256and a base urlhttps://contentgateway.grassecon.net, the result of the methods may be
as follows:toURI(sha256(foo))->"sha256:2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae"toURL(sha256(foo))->"https://contentgateway.grassecon.net/2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae"tokenURI(toUint(sha256(foo)))->"https://contentgateway.grassecon.net/2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae"Locator without URLGiven the datafoo, the digest algorithmsha256and no base url, the
result of the methods may be as follows:toURI(sha256(foo))->"sha256:2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae"toURL(sha256(foo))->""tokenURI(toUint(sha256(foo)))->"sha256:2c26b46b68ffc68ff99b453c1d30413413422d706483bfa0f98a5e886266e7ae"MinterAttached toERC20andERC721tokens that may be minted.Implements themint(...)andsafeMint(...)parts ofERC5679for
interoperability.ERC165 Interface identifier5878bcf4Solidity interface definitioninterface IMinter {
// Tokens are successfully minted; by who, to whom and how much
event Mint(address indexed _minter, address indexed _beneficiary, uint256 value);// Mint the specified value of tokens to the specified recipient
    function mintTo(address _beneficiary, uint256 value) external returns (bool);

    // Satisfies ERC5679 for ERC20
    function mint(address _beneficiary, uint256 value, bytes calldata _data) external;

    // Satisfies ERC5679 for ERC721
    function safeMint(address _beneficiary, uint256 value, bytes calldata _data) external;
}Example implementationhttps://git.grassecon.net/cicnet/erc20-demurrage-token.gitMsgEnables a reference "message" to describe the contract using an
off-chain resource.The reference may or may not be mutable.The interface complementsLocatorandMultiHashto generate locators
for how to resolve the reference.ERC165 Interface identifiera3002595Solidity interface definitioninterface IMsg {
// Emitted when a new message digest has been set
// Should not be emitted if the digest set is identical to the previous
event Msg(bytes _msgDigest);// Get the current message content hash
    function getMsg() external view returns(bytes memory);
}Example implementationgit://holbrook.no/eth-event-msg.gitRegistryThe Registry interface is a key-value store resolving well-known
contract identifier names to contract addresses.It currently has two distinct uses in the CIC context:Entry-point to discover all relevant contracts of CIC networks.Unique (ERC20) token symbol resolver.ERC165 Interface identifiereffbf671Solidity interface definitioninterface IRegistryClient {
// Address added to store with the given key
event AddressKey(bytes32 indexed _key, address _address);// Return the address of the contract identified by the given byte string
    function addressOf(bytes32) external view returns (address);

    // Indexed accessor for the full list of registred identifiers
    function identifier(uint256) external view returns (bytes32);

    // Number of registered interfaces
    function identifierCount() external view returns (uint256);
}Contract registry implementationgit://holbrook.no/eth-contract-registry.gitToken index implementationgit://holbrook.no/eth-contract-registry.gitSealSome smart contract parameters may need to be mutable over part of a
smart contract’s lifetime.This interface provides a method to explicitly signal when certain
parameters have been rendered immutable.The value ofsealState()must notdecrease, and must not exceedmaxSealState.maxSealStateis used to define thatall mutable parametershave been
rendered immutable. The practical implications of this will vary between
contracts.The implementer is encouraged to use simple, descriptive names in the
source code to describe the applicable seal states.Use cases of sealing include:Whether more tokens can be mintedAllow ownership of a contract to be transferredThe expiry time of a token (seeExpire)ERC165 Interface identifier0d7491f8Solidity interface definitioninterface ISeal {
// Seal state has changed.
event SealStateChange(bool indexed _final, uint256 _sealState);// The current seal state.
    function sealState() external view returns(uint256);

    // The numeric seal state in everything sealable has been sealed.
    function maxSealState() external view returns(uint256);
}Example implementationhttps://git.grassecon.net/cicnet/erc20-demurrage-token.gitTokenVendThis interface defines the mechanism for which a specific ERC20 token
may be exchanged for a different ERC20 token.A typical use-case is generation of voting tokens based on a momentary
voucher balance. This is especially useful if the original ERC20 token
is subject to decay (demurrage).The tokens used for exchangeSHOULDbe locked for the full duration
of holding the vended tokens.The withdrawal function may or may not allow partial withdrawals.ERC165 Interface identifier8a13249cSolidity interface definitioninterface ITokenVend {
// A new vended token has been created.
event TokenCreated(uint256 indexed _tokenIdx, uint256 indexed _supply, address _token);// Create corresponding vended tokens for the control token balance of the caller.  
    function getFor(address _token) external returns (uint256);

    // Recover control tokens that were used to retrieve the corresponding vended tokens.
    function withdrawFor(address _token) external returns (uint256);
}Reference implementationsgit://holbrook.no/erc20-vend.gitTokenVoteExecute elections with granular ERC20 token votes.A proposal submitted for vote may or may not contain multiple options.
If multiple options are available, an ERC20 token holder may distribute
its vote among the options with the granularity of the token balance.Voted tokensSHOULDbe locked until the voting has finalized.Finalization of voting should be callable by anyone.ERC165 Interface identifier28091366Solidity interface definitioninterface ITokenVote {// A new proposal has been created.
    event ProposalAdded(uint256 indexed _blockDeadline, uint256 indexed voteTargetPpm, uint256 indexed _proposalIdx);

    // A proposal vote has been completed.
    // The proposal is identified by the serial number in _proposalIdx. It is up to the implementer to define how the proposal should be retrieved by index.
    // The proposal result may be in one of three states:
    // * Ratified (_cancelled == false, _insufficient == false)
    // * Cancelled (_cancelled == true, _insufficient == false)
    // * Not reached quorum (_cancelled == false, _insufficient == true)
    event ProposalCompleted(uint256 indexed _proposalIdx, bool indexed _cancelled, bool indexed _insufficient, uint256 _totalVote);

    // Propose a new vote.
    // Voting is active until one of:
    // * total cancel vote reach quorum (_targetVotePpm, ppm = parts-per-million).
    // * _blockWait blocks from now.
    function propose(bytes32 _description, uint256 _blockWait, uint24 _targetVotePpm) external returns (uint256);

    // Same as propose(...), but provide options to vote on.
    function proposeMulti(bytes32 _description, bytes32[] memory _options, uint256 _blockWait, uint24 _targetVotePpm) external returns (uint256);

    // Get number of options available for the proposal.
    // This decides the boundary of the index that can be used with voteOptions(...)
    // If the result is 0, vote(...) can be used aswell.
    function optionCount(uint256 _proposalIdx) external view returns(uint256);

    // Get proposal option. Assumes that proposal was created with proposeMulti(...)
    function getOption(uint256 _proposalIdx, uint256 _optionIdx) external view returns (bytes32);

    // Get vote count for the given option.
    // If proposal has no options, it should be called with _optionIdx = 0
    function voteCount(uint256 _proposalIdx, uint256 _optionIdx) external view returns(uint256);

    // Vote on a proposal without options.
    // Assumes that proposal was created with propose(...) and will fail otherwise.
    function vote(uint256 _value) external returns (bool);

    // Vote on a proposal option. Assumes that proposal was created with proposeMulti(...).
    // Must work with a non-option proposal if _optionIndex is 0.
    function voteOption(uint256 _optionIndex, uint256 _value) external returns (bool);

    // Vote to cancel a proposal.
    // If cancel has the majority:
    // * A vote without options will have rejected the proposal description.
    // * A vote with options will have rejected the proposal description as well as all option descriptions.
    function voteCancel(uint256 _value) external returns (bool);

    // Finalize the vote for a proposal.
    // May be called if deadline has been passed, or if:
        // * quorum has been reached with cancel votes.
    // * quorum has been reached and proposal has no/only one option.
    function finalize() external returns (bool);
}Reference implementationsgit://holbrook.no/evm-tokenvote.gitWriterA complement to ERC173, which allows definition of a class of
super-users for a contract.A super-user address may performmoreactions than a "normal" address,
aswell assomeactions normally limited to thecontract owner.If ancontract owneris defined, No super-user should be able to
perform actions thatcontract ownercannot perform.Typically, only thecontract owner, if it is defined, can add or
remove a super-user.Some use-case examples of super-user actions include:Mint new tokens.Change the amount dispensed by the faucet.Edit access control lists.ERC165 Interface identifierabe1f1f5Solidity interface definitioninterface IWriter {
// A writer has been added by _executor
event WriterAdded(address _writer);// A writer has been removed by _executor
    event WriterDeleted(address _writer);

    // Add a new writer to the contract.
    function addWriter(address _writer) external returns (bool);

    // Remove existing writer from the contract.
    function deleteWriter(address _writer) external returns (bool);

    // Check whether the given address is a writer.
    function isWriter(address _writer) external view returns (bool);
}Example implementationhttps://git.grassecon.net/cicnet/erc20-demurrage-token.git