API Documentation

Restricted Access Functions

Functions accessible only by the contract owner or authorized clients.

1. send(uint256 rid, address rua, bytes data)

   • Description: Sends a packet to the designated receive chain.
   • Parameters:
     • rid: ID of the receive chain.
     • rua: Address of the receive application.
     • data: Data payload for the packet.

2. validateTransactionProof(uint256 csid, bytes key, bytes[] calldata receiptProof, bytes[] calldata transactionProof, bytes32 blockHash)

   • Description: Validates transaction and receipt proofs, ensuring secure cross-chain communication.
   • Parameters:
     • csid: ID of the send chain.
     • key: RLP key.
     • receiptProof: Proof data for the transaction receipt.
     • transactionProof: Proof data for the transaction.
     • blockHash: Hash of the relevant block.

3. registerChain(uint256 chainId, IFullCheckpoint csc, Endpoint endpoint)

   • Description: Registers a new chain for packet reception.
   • Parameters:
     • chainId: ID of the chain being registered.
     • csc: Checkpoint contract for the receive chain.
     • endpoint: Endpoint contract for the send chain.

4. approveApplication(uint256 rid, address rua, address sua)

   • Description: Approves both a receive and send application for cross-chain interaction.
   • Parameters:
     • rid: ID of the receive chain.
     • rua: Address of the receive application.
     • sua: Address of the send application.

5. approveRua(uint256 rid, address rua)

   • Description: Approves a receive application (rua) for a specific chain.
   • Parameters:
     • rid: ID of the receive chain.
     • rua: Address of the receive application.

6. approveSua(address sua)

   • Description: Approves a send application (sua) for packet sending.
   • Parameters:
     • sua: Address of the send application.

7. revokeApplication(uint256 rid, address rua, address sua)

   • Description: Revokes approval for both a receive and send application.
   • Parameters:
     • rid: ID of the receive chain.
     • rua: Address of the receive application.
     • sua: Address of the send application.

8. revokeRua(uint256 rid, address rua)

   • Description: Revokes approval for a specific receive application.
   • Parameters:
     • rid: ID of the receive chain.
     • rua: Address of the receive application.

9. revokeSua(address sua)

   • Description: Revokes approval for a send application.
   • Parameters:
     • sua: Address of the send application.

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Public Functions

Functions accessible by any user or contract on the blockchain.

1. packetHash() returns (bytes32)

   • Description: Retrieves the hash for the Packet event.

2. getRlp(bytes memory key, bytes[] calldata proof, bytes32 root) returns (bytes memory)

   • Description: Retrieves RLP data based on a Merkle Patricia proof.

3. getFailureDataLength(uint256 rid) returns (uint256)

   • Description: Retrieves the count of failed data entries for a specified receive chain.

4. getReceiveChainLastIndex(uint256 chainId) returns (uint256)

   • Description: Retrieves the last index for a specified receive chain.

5. getSendChain(uint256 chainId) returns (Chain memory)

   • Description: Retrieves details of a send chain based on its ID.

6. getSendChainIds() returns (uint256[] memory)

   • Description: Returns an array of all registered send chain IDs.

7. allowanceRua(uint256 rid, address rua) returns (bool)

   • Description: Checks if a receive application is approved for a specific chain.
   • Parameters:
     • rid: ID of the receive chain.
     • rua: Address of the receive application.

8. allowanceSua(address sua) returns (bool)

   • Description: Checks if a send application is approved.
   • Parameters:
     • sua: Address of the send application.

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Algorithms and Rules

• Packet Validation: Ensures that only approved applications on registered chains can send packets. The contract validates each transaction’s authenticity by verifying proofs of transaction and receipt.
• Failure Data Handling: If a packet transmission fails, the contract records it, allowing for potential retries or analysis.
• Chain Registration: Only authorized users (contract owner) can register new chains, safeguarding against unauthorized cross-chain communication.