AccessProofCondition

Implementation of the Access Condition with transfer proof. The idea is that the hash of the decryption key is known before hand, and the key matching this hash is passed from data provider to the buyer using this smart contract. Using ZK proof the key is kept hidden from outsiders. For the protocol to work, both the provider and buyer need to have public keys in the babyjub curve. To initiate the deal, buyer will pass the key hash and the public keys of participants. The provider needs to pass the cipher text encrypted using MIMC (symmetric encryption). The secret key for MIMC is computed using ECDH (requires one public key and one secret key for the curve). The hash function that is used is Poseidon.

Functions¶

initialize¶

  function initialize(
    address _owner,
    address _conditionStoreManagerAddress,
    address _agreementStoreManagerAddress,
    address _disputeManagerAddress
  ) external

initialize init the contract with the following parameters

this function is called only once during the contract initialization.

Parameters:¶

Name	Type	Description
`_owner`	address	contract's owner account address
`_conditionStoreManagerAddress`	address	condition store manager address
`_agreementStoreManagerAddress`	address	agreement store manager address
`_disputeManagerAddress`	address	dispute manager address

hashValues¶

  function hashValues(
    uint256 _origHash,
    uint256[2] _buyer,
    uint256[2] _provider
  ) public returns (bytes32)

hashValues generates the hash of condition inputs with the following parameters

Parameters:¶

Name	Type	Description
`_origHash`	uint256	is the hash of the key
`_buyer`	uint256[2]	buyer public key
`_provider`	uint256[2]	provider public key

Return Values:¶

Name	Type	Description
`bytes32`	uint256	hash of all these values
### fulfill
`function fulfill( bytes32 _agreementId, uint256 _origHash, uint256[2] _buyer, uint256[2] _provider, uint256[2] _cipher, bytes _proof ) public returns (enum ConditionStoreLibrary.ConditionState)`
fulfill key transfer

The key with hash _origHash is transferred to the _buyer from _provider.

Parameters:¶

Name	Type	Description
`_agreementId`	bytes32	associated agreement
`_origHash`	uint256	is the hash of data to access
`_buyer`	uint256[2]	buyer public key
`_provider`	uint256[2]	provider public key
`_cipher`	uint256[2]	encrypted version of the key
`_proof`	bytes	SNARK proof that the cipher text can be decrypted by buyer to give the key with hash _origHash

Return Values:¶

Name	Type	Description
`condition`	bytes32	state (Fulfilled/Aborted)
## Events
### Fulfilled
`event Fulfilled( )`