Unsafe Code Guide
Cypheron Core contains unsafe Rust code required for FFI integration with NIST C reference implementations. This section provides an overview of our unsafe code usage and safety guarantees.
For complete documentation of all unsafe code blocks, see the comprehensive Unsafe Code Guide.
Overview
The library contains 91 unsafe blocks across 19 files, each with detailed safety justifications. All unsafe code is:
- Documented with safety invariants
- Required for FFI with C vendor code
- Minimized to essential operations
- Reviewed for memory safety
Categories of Unsafe Code
1. FFI Function Calls
Direct calls to C cryptographic functions from NIST reference implementations.
Safety Guarantee: Buffer bounds validated before calls, return codes checked.
2. Pointer Dereferencing
Converting Rust slices to raw pointers for C function parameters.
Safety Guarantee: Pointers derived from valid Rust references, lifetimes controlled.
3. Memory Operations
Buffer initialization and secure cleanup operations.
Safety Guarantee: All operations within allocated bounds, proper initialization verified.
4. Platform-Specific Code
OS-specific secure random number generation and memory protection.
Safety Guarantee: Platform APIs used according to documentation, error handling comprehensive.
Security Audit Considerations
Each unsafe block is documented with:
- Safety Invariant: What conditions must hold for safety
- Justification: Why the unsafe operation is necessary
- Verification: How safety is ensured in practice
- Error Handling: What happens when invariants are violated
Complete Documentation
For detailed analysis of every unsafe block including line-by-line safety justifications, see:
This comprehensive guide provides security auditors with complete visibility into all potentially unsafe operations.