Module mldsa 

ML-DSA post-quantum signatures standardized in FIPS 204.

This module implements the ML-DSA-44, ML-DSA-65 and ML-DSA-87 parameter sets through distinct key types:

Parameter set	Secret key	Public key	Public key size	Signature size
ML-DSA-44	MlDsa44SecretKey	MlDsa44PublicKey	1312 B	2420 B
ML-DSA-65	MlDsa65SecretKey	MlDsa65PublicKey	1952 B	3309 B
ML-DSA-87	MlDsa87SecretKey	MlDsa87PublicKey	2592 B	4627 B

Signing

Signing is stateful: build a secret key from a 32-byte seed with new (or with generate for a fresh random key), then call sign (randomized) or sign_derand (deterministic for a fixed nonce).

The expanded key caches the NTT-domain matrix and secret vectors, so repeated signatures skip key generation. It is a fixed-size value with no heap allocation:

let key = MlDsa65SecretKey::new(&seed);
let signature = key.sign_derand(b"message", b"", &[0u8; 32]).unwrap();
assert!(key.public_key().verify(b"message", &signature, b"").is_ok());

Verification

Verification is stateless: the public key returned by the secret key’s public_key method (or built from raw bytes with from_bytes) exposes verify for a message and optional context, and verify_external_mu for a precomputed 64-byte message representative (FIPS 204 “external μ”). Both return MlDsaError on failure.

Structs

MlDsa44PublicKey

An ML-DSA-44 public key.

MlDsa44SecretKey

An expanded ML-DSA-44 secret key.

MlDsa65PublicKey

An ML-DSA-65 public key.

MlDsa65SecretKey

An expanded ML-DSA-65 secret key.

MlDsa87PublicKey

An ML-DSA-87 public key.

MlDsa87SecretKey

An expanded ML-DSA-87 secret key.

Enums

MlDsaError

Constants

ML_DSA_44_CONTEXT_MAX_LEN

Maximum length in bytes of an ML-DSA-44 context string.

ML_DSA_44_PUBLIC_KEY_SIZE

Size in bytes of an encoded ML-DSA-44 public key.

ML_DSA_44_SECRET_KEY_SIZE

Size in bytes of an initialized MlDsa44SecretKey.

ML_DSA_44_SEED_SIZE

Size in bytes of an ML-DSA-44 seed (private key).

ML_DSA_44_SIGNATURE_SIZE

Size in bytes of an encoded ML-DSA-44 signature.

ML_DSA_65_CONTEXT_MAX_LEN

Maximum length in bytes of an ML-DSA-65 context string.

ML_DSA_65_PUBLIC_KEY_SIZE

Size in bytes of an encoded ML-DSA-65 public key.

ML_DSA_65_SECRET_KEY_SIZE

Size in bytes of an initialized MlDsa65SecretKey.

ML_DSA_65_SEED_SIZE

Size in bytes of an ML-DSA-65 seed (private key).

ML_DSA_65_SIGNATURE_SIZE

Size in bytes of an encoded ML-DSA-65 signature.

ML_DSA_87_CONTEXT_MAX_LEN

Maximum length in bytes of an ML-DSA-87 context string.

ML_DSA_87_PUBLIC_KEY_SIZE

Size in bytes of an encoded ML-DSA-87 public key.

ML_DSA_87_SECRET_KEY_SIZE

Size in bytes of an initialized MlDsa87SecretKey.

ML_DSA_87_SEED_SIZE

Size in bytes of an ML-DSA-87 seed (private key).

ML_DSA_87_SIGNATURE_SIZE

Size in bytes of an encoded ML-DSA-87 signature.