Falcon (FN-DSA)

Falcon is a lattice-based signature scheme with compact signatures.

Algorithm Identifiers

From packages/cryptography/src/provider.ts:

type PqcSignatureAlgorithm = 
  | "falcon-512"
  | "falcon-1024";

liboqs Implementation

From packages/cryptography/src/providers/liboqs.ts:

const ALGORITHM_MAP = {
  "falcon-512": ["Falcon512", "Falcon-512"],
  "falcon-1024": ["Falcon1024", "Falcon-1024"],
};

Parameter Sets

Variant	QNSP Identifier	liboqs Name	Security Level
Falcon-512	falcon-512	Falcon-512	NIST Level 1
Falcon-1024	falcon-1024	Falcon-1024	NIST Level 5

Overview

• Type: Digital Signature Algorithm
• Standard: FN-DSA (NIST selected)
• Security basis: NTRU lattices

QNSP Usage

Falcon is supported but not the default signature algorithm. From codebase analysis:

• Default: Dilithium-2 (for JWT signing)
• Falcon availability: Supported via liboqs provider
• Test coverage: Integration tests in providers/liboqs.integration.test.ts

Code Examples

From integration tests:

// Falcon-512 operations
const { keyPair } = await provider.generateKeyPair({ 
  algorithm: "falcon-512" 
});

const { signature } = await provider.sign({
  algorithm: "falcon-512",
  data: message,
  privateKey: keyPair.privateKey,
});

const isValid = await provider.verify({
  algorithm: "falcon-512",
  data: message,
  signature,
  publicKey: keyPair.publicKey,
});

PQC-TLS Support

From packages/cryptography/src/tls/pqc-tls.ts:

const OQS_ALGORITHM_MAP = {
  "falcon-512": "falcon512",
  "falcon-1024": "falcon1024",
};