wolfCrypt drops liboqs for native post-quantum crypto

wolfSSL’s wolfCrypt library has ended its reliance on the liboqs post-quantum cryptography (PQC) library, completing a transition to fully native implementations. The change removes the external dependency while maintaining support for all NIST-standardized PQC algorithms and experimental schemes, including the recently added FrodoKEM and the final holdout, Falcon. The shift is aimed at production environments where footprint, memory behavior, and platform-specific optimizations are critical, such as embedded systems, real-time operating systems (RTOS), and hardware-backed secure boot deployments.

What changed

wolfCrypt previously used liboqs as a wrapper for several post-quantum algorithms during the standardization process. As NIST finalized its PQC standards in 2024—including ML-KEM (FIPS 203), ML-DSA (FIPS 204), and SLH-DSA (FIPS 205)—wolfSSL replaced the liboqs integrations with native implementations. The last remaining dependency was Falcon, a lattice-based digital signature algorithm that also serves as the basis for NIST’s in-development FN-DSA standard (FIPS 206). With Falcon now implemented directly in wolfCrypt, the library no longer requires liboqs for any algorithm.

The native implementation of Falcon supports both Falcon-512 and Falcon-1024 across a range of platforms, from x86-64 and AArch64 systems to Linux kernel modules and Cortex-M microcontrollers. Testing on a 32-bit ARM Cortex-M33 demonstrated that wolfCrypt could complete Falcon-1024 key generation, signing, and verification, a task the PQClean implementation used by liboqs could not achieve due to private key validation failures.

New additions and coverage

Alongside the removal of liboqs, wolfCrypt has expanded its native PQC portfolio with FrodoKEM, a lattice-based key encapsulation mechanism that provides an alternative to ML-KEM. FrodoKEM is particularly relevant for organizations seeking cryptographic diversity in their post-quantum migration strategies. The library supports FrodoKEM-640, FrodoKEM-976, and FrodoKEM-1344, including variants using AES, SHAKE, and ephemeral eFrodoKEM. Optimizations for x86-64 and ARM platforms, along with reduced-memory options, make it viable for resource-constrained environments.

wolfCrypt’s native PQC coverage now includes:

• NIST-standardized algorithms: ML-KEM (FIPS 203), ML-DSA (FIPS 204), SLH-DSA (FIPS 205)
• Stateful hash-based signatures: LMS, HSS, XMSS, and XMSS-MT (NIST SP 800-208)
• Experimental and future-ready schemes: FrodoKEM, Falcon, and FN-DSA

Why the shift matters

liboqs remains a valuable tool for research, interoperability testing, and prototyping, but its documentation explicitly advises against using it to protect sensitive production data. Production deployments, particularly in embedded, RTOS, and hardware-backed environments, require tighter control over footprint, memory usage, and platform-specific optimizations. Native wolfCrypt implementations address these needs by offering:

• Hardware and secure-element offload via crypto callbacks
• Configurations for small-memory and small-stack environments
• Architecture-specific acceleration for x86-64 and ARM
• Kernel-compatible execution paths
• A unified API and testing infrastructure

The removal of liboqs simplifies deployment for teams moving PQC from evaluation to production in IoT, secure boot, TLS, and kernel-level applications. wolfCrypt now provides a single, integrated native portfolio without external dependencies, reducing complexity for developers targeting constrained or specialized environments.

What to watch

While wolfCrypt’s native PQC portfolio is now complete for current standards, the landscape continues to evolve. NIST’s FN-DSA standard, based on Falcon, remains in development, and future updates to wolfCrypt may incorporate additional algorithms or optimizations as the post-quantum ecosystem matures. Organizations planning long-term PQC migrations should monitor these developments, particularly for use cases requiring cryptographic diversity or compliance with emerging standards.