The Tox protocol and its clients needed independent security auditing to ensure the encryption implementation was sound, the peer-to-peer architecture had no exploitable weaknesses, and the C codebase had no memory safety vulnerabilities that could compromise user privacy.
Conducted a comprehensive security audit of the Tox protocol and implemented security hardening in the uTox client. Reviewed the cryptographic implementation (NaCl/libsodium), analyzed the DHT peer discovery for potential attack vectors, audited the C codebase for buffer overflows, use-after-free, and other memory safety issues. This was my first project — it shaped my entire approach to security-first development.
> Protocol-level audit first — understanding the cryptographic foundations before reviewing client implementation ensured no false sense of security from correct code on a flawed protocol
> Focus on memory safety in C — manual memory management in C is the primary attack surface for a security-critical application, so buffer overflows and use-after-free were top priority
> DHT analysis for privacy — peer discovery via distributed hash table can leak metadata even with encrypted payloads, requiring careful analysis of what information is exposed during the handshake
Low-level systems programming, manual memory management
End-to-end encryption, key exchange, authentication
Decentralized peer discovery, no central servers
Buffer overflow analysis, cryptographic review
Visual coming soon