WebTerm: Confidential Decentralized File System

ETHGlobal 2024 ETHOnline Hackathon Submission

Project Concept

This project implements a decentralized, privacy-preserving file system using Web3 technologies, Fully Homomorphic Encryption (FHE), and IPFS. It provides users with a familiar file system interface while leveraging blockchain for authentication and secure metadata storage, and IPFS for decentralized file storage.

Key Features:

Web3 Authentication: Users connect and sign in using their blockchain wallet. Privacy-Preserving: Utilizes FHENIX FHE for encrypting user data on the blockchain. Decentralized Storage: Files are stored on IPFS, with encrypted references on the blockchain. Familiar Interface: Mimics a traditional file system with directories and files. Access Control: Supports both public and private files/directories. Confidential String Storage: Demonstrates encrypted string storage and retrieval. Author Verification: Verify content creators without revealing identities.

Youtube Demo | Live Demo

System Flow

The following diagram illustrates the high-level flow of the system:

sequenceDiagram
    participant User
    participant Frontend
    participant Smart Contract
    participant IPFS

    User->>Frontend: Connect wallet
    Frontend->>User: Request signature
    User->>Frontend: Sign message
    Frontend->>Smart Contract: Verify signature
    Smart Contract->>Frontend: Authentication success
    Frontend->>Smart Contract: Request encrypted user data
    Smart Contract->>Frontend: Return encrypted data
    Frontend->>User: Decrypt data locally
    User->>Frontend: Request file operation
    Frontend->>IPFS: Store/Retrieve file
    IPFS->>Frontend: File data
    Frontend->>User: Display file/directory

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How It Works

1. Authentication: Users connect their Web3 wallet and sign a message to prove ownership.
2. Data Retrieval: Upon successful authentication, encrypted user data is fetched from the blockchain.
3. Local Decryption: User data is decrypted client-side using the user's private key.
4. File Operations:
   • File metadata and structure are stored on the blockchain using FHE.
   • Actual file contents are stored on IPFS.
   • Encrypted IPFS CIDs are stored on the blockchain.
5. Access Control: The smart contract manages file ownership and public/private status.

Getting Started

• Visit WebTerm and connect your wallet.
• Register to store and access FHE encrypted files.
• Upload files to IPFS and store the encrypted CIDs on the blockchain.
• Setup public or private directories and files. Manage access permissions directly onchain.

Technologies Used

• Blockchain: FHENIX Helium Testnet
• Smart Contract: Solidity
• Frontend: Next.js
• Fully Homomorphic Encryption: FHENIXs
• Decentralized Storage: IPFS (not implemented)