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S-Cloud+ Vault Explorer

Interactive demonstration of the S-Cloud+ Vault — a secure container for encrypted payloads using lattice-based Key Encapsulation (ePrint 2024/1306, Wang et al. — Tsinghua University / Huawei). Featuring BW₃₂ Barnes-Wall lattice coding, ternary secrets, and FO-transformed IND-CCA2 security.

Reality Check

What this project demonstrates

  • Client-side encryption model
  • Secure container concept
  • Key derivation → encryption flow

What this project simplifies

  • No secure enclave / HSM
  • No hardened authentication layer
  • No malicious client defense

What this project is NOT

  • Not production-ready secure storage
  • Not resistant to XSS or compromised browser
  • Not a substitute for audited systems

Security Model

Threats Considered

  • Data-at-rest exposure
  • Network interception

Threats NOT Covered

  • Malicious browser environment
  • Keylogging
  • XSS / injected scripts

Reality Check

What This Demo Is

  • A faithful TypeScript port of ePrint 2024/1306 parameters and algorithms
  • Real SHAKE-128/256 and SHA3-256 running in your browser (pure Keccak)
  • Full KEM round-trip: KeyGen → Encaps → Decaps with implicit rejection
  • BW₃₂ lattice coding with measurable error-correction radius

What This Demo Is Not

  • Not constant-time — JavaScript cannot guarantee timing-safe execution
  • Not audited or suitable for production key exchange
  • Not a substitute for a vetted C/Rust implementation
  • Not endorsed by the S-Cloud+ authors or any standards body

What the Textbook Doesn't Show

Standard LWE-KEM treatments stop at "add noise, hope it rounds away." S-Cloud+ takes a different path: Barnes-Wall BW₃₂ lattice coding provides structured error correction that doubles the tolerable noise compared to simple rounding. This is the key insight — by encoding each 5-bit message chunk into a 32-dimensional lattice point, the decoder can correct errors up to the packing radius of BW₃₂, letting the authors shrink modulus and matrix dimensions while maintaining the same security level. The result: smaller keys than FrodoKEM at comparable strength, without relying on algebraic ring structure like ML-KEM.