StealthComm: Private Blockchain Communication

Abstract

Modern messaging platforms frequently compromise user privacy and security in favor of convenience, relying on centralized infrastructures that can expose users to data breaches, surveillance, and censorship. To address these vulnerabilities, we propose StealthComm, a blockchain-based secure communication system designed to provide end-to-end encryption, privacy, censorship resistance, and cryptographic data integrity. StealthComm employs a modular cryptographic architecture to enhance anonymity. Messages are encrypted locally using AES-256-CBC with cryptographically secure random initialization vectors (IVs) and transmitted through the Tor network to help mask IP addresses and reduce exposure to traffic analysis. For sender and receiver anonymity, the system integrates Monero-inspired privacy protocols. Stealth Addresses generate ephemeral, one-time receiving addresses to conceal recipient identities, while Ring Signatures anonymize senders by cryptographically associating their signatures with a group of decoy members. These features are implemented within a dedicated Crypto Module, while message dispatch and retrieval are managed through separate Sender and Receiver Modules to maintain functional isolation. Encrypted messages, along with their ring signatures and associated decoy members, are stored on the InterPlanetary File System (IPFS), a decentralized storage network. To provide tamper-evident indexing, the SHA-256 hash of each message is recorded on the Ethereum blockchain through a Solidity smart contract, while the message payload remains off-chain to improve scalability. Each message is indexed using its stealth address, allowing the intended recipient with the corresponding private key to identify and decrypt the communication. The system uses Ethers.js for interaction with the Ethereum blockchain, with testing conducted using Remix IDE and Ganache to validate smart contracts and simulate network behavior. By eliminating centralized servers and integrating end-to-end encryption, Tor-based anonymized routing, decentralized storage, and blockchain-based integrity verification, StealthComm demonstrates the potential for privacy-preserving communication. Although the architecture is resource-intensive, it provides resistance to several common security threats while promoting privacy, transparency, and user autonomy. The proposed system offers a decentralized communication framework suitable for applications requiring enhanced confidentiality, including secure organizational communication and privacy-sensitive information exchange.