SecretPlatform - Confidential Transfer Platform

A decentralized platform that enables users to store encrypted cUSDT tokens and perform confidential transfers using Zama's Fully Homomorphic Encryption (FHE) technology.

🔒 Core Features

SecretPlatform provides a complete confidential transaction ecosystem with the following capabilities:

✅ Confidential Token Management

• cUSDT Token: Custom implementation of confidential USDT with wrap/unwrap functionality
• Encrypted Balances: All user balances are stored and processed in encrypted form
• Confidential Transfers: Support for encrypted transfer and transferFrom operations

✅ Platform Operations

• Encrypted Deposits: Users can deposit cUSDT with encrypted amounts
• Encrypted Withdrawals: Withdraw any encrypted amount from platform balance
• Secret Transfers: Transfer encrypted amounts to encrypted addresses
• Claim System: Recipients can claim transfers using encrypted claim mechanism

🏗️ Architecture Overview

Smart Contracts

cUSDT Contract (cUSDT.sol)

• Purpose: Confidential USDT token implementation
• Base: Extends ConfidentialFungibleTokenERC20Wrapper from OpenZeppelin Confidential Contracts
• Key Features:
  • Wrap/unwrap regular USDT to confidential cUSDT
  • Full confidential ERC20 interface with encrypted transfer methods
  • 6-decimal precision for USDT compatibility
  • ACL (Access Control List) integration for permission management

SecretPlatform Contract (SecretPlatform.sol)

• Purpose: Main platform contract managing user balances and transfers
• Key Components:
  • userBalances: Encrypted balance mapping for platform users
  • transferRecords: Storage for pending encrypted transfers
  • transferExists: Boolean flags for transfer record existence
• Core Functions:
  • deposit(): Deposit cUSDT to platform with encrypted amounts
  • withdraw() / withdrawAll(): Withdraw encrypted amounts from platform
  • encryptedTransferTo(): Create encrypted transfers to specified addresses
  • encryptClaim(): Claim pending encrypted transfers

Technology Stack

• Framework: Hardhat development environment
• Encryption: Zama FHE (Fully Homomorphic Encryption)
  • Supports encrypted operations without decryption
  • Maintains privacy throughout transaction lifecycle
• Base Contracts: OpenZeppelin Confidential Contracts
• Network: Ethereum Sepolia Testnet with FHE support
• Frontend: React with TypeScript and Zama SDK integration

🚀 Implementation Status

✅ Completed Components

Component	Status	Description
cUSDT Contract	✅ Complete	Custom confidential token with wrapper functionality
SecretPlatform Contract	✅ Complete	All core platform features implemented
Frontend Application	✅ Complete	Full Web interface in /app directory
Test Suite	✅ Complete	Contract functionality tests
Deployment Scripts	✅ Complete	Automated deployment to testnet

🔧 Key Implementation Details

• No OpenZeppelin Dependency: Custom implementation instead of relying on ConfidentialFungibleTokenERC20Wrapper
• ACL Integration: Proper access control list management for encrypted data
• Error Handling: Comprehensive error tracking for confidential operations
• Gas Optimization: Efficient FHE operations and minimal on-chain storage

📁 Project Structure

Secret_Platform/
├── contracts/              # Smart contract source files
│   ├── cUSDT.sol           # Confidential USDT token implementation
│   ├── SecretPlatform.sol  # Main platform contract
│   ├── MockERC20.sol       # Mock USDT for testing
│   └── FHECounter.sol      # Example FHE contract
├── app/                    # Frontend application
│   ├── src/
│   │   ├── components/     # React components
│   │   ├── contexts/       # React contexts (Wallet, ZamaSDK)
│   │   └── contracts/      # Contract ABIs and configurations
│   └── package.json
├── deploy/                 # Deployment scripts
├── test/                   # Test files
├── docs/                   # Zama documentation
└── hardhat.config.ts       # Hardhat configuration

🛠️ Development Setup

Prerequisites

• Node.js: Version 20 or higher
• npm/yarn/pnpm: Package manager
• Wallet: MetaMask or compatible Web3 wallet

Installation

1. Clone and install dependencies

   git clone <repository>
   cd Secret_Platform
   npm install

2. Set up environment variables

   npx hardhat vars set MNEMONIC
   npx hardhat vars set INFURA_API_KEY
   npx hardhat vars set ETHERSCAN_API_KEY

3. Compile contracts

   npm run compile

4. Run tests

   npm run test

5. Deploy to Sepolia Testnet

   npx hardhat deploy --network sepolia

Frontend Setup

1. Navigate to app directory

   cd app
   npm install

2. Start development server

   npm run dev

🔐 Security Features

• End-to-End Encryption: All sensitive data encrypted using Zama FHE
• Access Control: Comprehensive ACL system for encrypted data access
• No Plaintext Exposure: Amounts and balances never exposed on-chain
• Operator Pattern: Secure delegation system for token operations
• Input Validation: Cryptographic proofs for all encrypted inputs

📋 Usage Example

// Deploy cUSDT with underlying USDT
cUSDT cusdt = new cUSDT(IERC20(usdtAddress));

// Deploy SecretPlatform
SecretPlatform platform = new SecretPlatform(address(cusdt));

// User deposits encrypted amount
platform.deposit(encryptedAmount, inputProof);

// User creates encrypted transfer
platform.encryptedTransferTo(recipient, encryptedAmount, inputProof);

// Recipient claims transfer
platform.encryptClaim();

🌐 Network Configuration

Sepolia Testnet

• Network ID: 11155111
• FHEVM Gateway ID: 55815
• Relayer URL: https://relayer.testnet.zama.cloud

Contract Addresses (Sepolia)

• FHE Executor: 0x848B0066793BcC60346Da1F49049357399B8D595
• ACL Contract: 0x687820221192C5B662b25367F70076A37bc79b6c
• KMS Verifier: 0x1364cBBf2cDF5032C47d8226a6f6FBD2AFCDacAC

📚 Documentation

• Zama FHE Documentation: docs/zama_llm.md
• Zama Relayer SDK: docs/zama_doc_relayer.md
• FHEVM Protocol: https://docs.zama.ai/fhevm
• OpenZeppelin Confidential: https://docs.openzeppelin.com/contracts-cairo

📄 License

This project is licensed under the MIT License. See the LICENSE file for details.

🆘 Support

• GitHub Issues: Report bugs or request features
• Zama Community: Community Forum
• Discord: Zama Discord

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