COTI MCP Server

// SPDX-License-Identifier: MIT pragma solidity ^0.8.19; import "coti-contracts/contracts/utils/mpc/MpcCore.sol"; /** * @title Private Message Storage for COTI Blockchain * @notice This is a simple template for storing encrypted messages on COTI * @dev Uses COTI's confidential types (utString, ctString) for encrypted message storage * * Key Features: * - Per-user encrypted message storage using COTI's MPC (Multi-Party Computation) * - Messages are encrypted and can only be read by the user who wrote them * - Uses utString (user encrypted string) for storage and ctString for reading * * MPC Types Used: * - utString: User-encrypted string (stored on-chain) * - gtString: General encrypted string (intermediate processing) * - ctString: Ciphertext string (returned to users) * - itString: Input ciphertext string (for writing) */ contract Message { utString private _message; constructor() { gtString memory message_ = MpcCore.setPublicString(""); _message = MpcCore.offBoardCombined(message_, msg.sender); } function read() public view returns (ctString memory) { return _message.userCiphertext; } function write(itString calldata value) external { gtString memory message_ = MpcCore.validateCiphertext(value); _message = MpcCore.offBoardCombined(message_, msg.sender); } }