Enum MLKEMCiphertext

pub enum MLKEMCiphertext {
    MLKEM512(Box<Ciphertext>),
    MLKEM768(Box<Ciphertext>),
    MLKEM1024(Box<Ciphertext>),
}

A ciphertext containing an encapsulated shared secret for ML-KEM.

MLKEMCiphertext represents a ciphertext produced by the ML-KEM (Module Lattice-based Key Encapsulation Mechanism) post-quantum algorithm during the encapsulation process. It contains an encapsulated shared secret that can only be recovered by the corresponding private key.

It supports multiple security levels through the variants:

• MLKEM512: NIST security level 1 (roughly equivalent to AES-128), 768 bytes
• MLKEM768: NIST security level 3 (roughly equivalent to AES-192), 1088 bytes
• MLKEM1024: NIST security level 5 (roughly equivalent to AES-256), 1568 bytes

Examples

use bc_components::MLKEM;

// Generate a keypair
let (private_key, public_key) = MLKEM::MLKEM512.keypair();

// Encapsulate a shared secret using the public key
let (shared_secret_a, ciphertext) = public_key.encapsulate_new_shared_secret();

// Decapsulate the shared secret using the private key
let shared_secret_b = private_key.decapsulate_shared_secret(&ciphertext).unwrap();

// Both shared secrets should be the same
assert_eq!(shared_secret_a, shared_secret_b);

Variants

MLKEM512(Box<Ciphertext>)

An ML-KEM-512 ciphertext (NIST security level 1)

MLKEM768(Box<Ciphertext>)

An ML-KEM-768 ciphertext (NIST security level 3)

MLKEM1024(Box<Ciphertext>)

An ML-KEM-1024 ciphertext (NIST security level 5)

Implementations

impl MLKEMCiphertext

pub fn level(&self) -> MLKEM

Returns the security level of this ML-KEM ciphertext.

pub fn size(&self) -> usize

Returns the size of this ML-KEM ciphertext in bytes.

pub fn as_bytes(&self) -> &[u8]

Returns the raw bytes of this ML-KEM ciphertext.

pub fn from_bytes(level: MLKEM, bytes: &[u8]) -> Result<Self>

Creates an ML-KEM ciphertext from raw bytes and a security level.

Parameters

• level - The security level of the ciphertext.
• bytes - The raw bytes of the ciphertext.

Returns

An MLKEMCiphertext if the bytes represent a valid ciphertext for the given level, or an error otherwise.

Errors

Returns an error if the bytes do not represent a valid ML-KEM ciphertext for the specified security level.

Trait Implementations

impl CBORTagged for MLKEMCiphertext

Defines CBOR tags for ML-KEM ciphertexts.

fn cbor_tags() -> Vec<Tag>

Returns the CBOR tag for ML-KEM ciphertexts.

impl CBORTaggedDecodable for MLKEMCiphertext

Implements CBOR decoding for ML-KEM ciphertexts.

fn from_untagged_cbor(untagged_cbor: CBOR) -> Result<Self>

Creates an MLKEMCiphertext from untagged CBOR.

Errors

Returns an error if the CBOR value doesn’t represent a valid ML-KEM ciphertext.

fn from_tagged_cbor(cbor: CBOR) -> Result<Self, Error>

where Self: Sized,

Creates an instance of this type by decoding it from tagged CBOR.

fn from_tagged_cbor_data(data: impl AsRef<[u8]>) -> Result<Self, Error>

where Self: Sized,

Creates an instance of this type by decoding it from binary encoded tagged CBOR.

fn from_untagged_cbor_data(data: impl AsRef<[u8]>) -> Result<Self, Error>

where Self: Sized,

Creates an instance of this type by decoding it from binary encoded untagged CBOR.

impl CBORTaggedEncodable for MLKEMCiphertext

Implements CBOR encoding for ML-KEM ciphertexts.

fn untagged_cbor(&self) -> CBOR

Creates the untagged CBOR representation as an array with level and ciphertext bytes.

fn tagged_cbor(&self) -> CBOR

Returns the tagged CBOR encoding of this instance.

fn tagged_cbor_data(&self) -> Vec<u8>

Returns the tagged value in CBOR binary representation.

impl Clone for MLKEMCiphertext

fn clone(&self) -> MLKEMCiphertext

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for MLKEMCiphertext

Provides debug formatting for ML-KEM ciphertexts.

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the ciphertext as a string for debugging purposes.

impl From<MLKEMCiphertext> for CBOR

Converts an MLKEMCiphertext to CBOR.

fn from(value: MLKEMCiphertext) -> Self

Converts to tagged CBOR.

impl PartialEq for MLKEMCiphertext

fn eq(&self, other: &MLKEMCiphertext) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl TryFrom<CBOR> for MLKEMCiphertext

Attempts to convert CBOR to an MLKEMCiphertext.

fn try_from(cbor: CBOR) -> Result<Self>

Converts from tagged CBOR.

type Error = Error

The type returned in the event of a conversion error.

impl StructuralPartialEq for MLKEMCiphertext