signet::forge::crypto::KyberKem Class Reference

Kyber-768 Key Encapsulation Mechanism (NIST FIPS 203 / ML-KEM-768). More...

#include <post_quantum.hpp>

Classes
struct	EncapsulationResult
	Result of Kyber-768 encapsulation: ciphertext to send + shared secret to keep. More...
struct	KeyPair
	Kyber-768 keypair: public key for encapsulation, secret key for decapsulation. More...

Static Public Member Functions
static expected< KeyPair >	generate_keypair ()
	Generate a Kyber-768 keypair.
static expected< EncapsulationResult >	encapsulate (const uint8_t *public_key, size_t pk_size)
	Generate a shared secret from a recipient's public key (encapsulation).
static expected< std::vector< uint8_t > >	decapsulate (const uint8_t *ciphertext, size_t ct_size, const uint8_t *secret_key, size_t sk_size)
	Recover the shared secret from ciphertext + secret key (decapsulation).

Static Public Attributes
static constexpr size_t	PUBLIC_KEY_SIZE = 1184
	Kyber-768 public key size (stub default).
static constexpr size_t	SECRET_KEY_SIZE = 2400
	Kyber-768 secret key size (stub default).
static constexpr size_t	CIPHERTEXT_SIZE = 1088
	Kyber-768 ciphertext size (stub default).
static constexpr size_t	SHARED_SECRET_SIZE = 32
	Shared secret size (256 bits, for AES-256).

Detailed Description

Kyber-768 Key Encapsulation Mechanism (NIST FIPS 203 / ML-KEM-768).

Used to establish shared AES-256 keys between Parquet writer and reader. Provides approximately 192-bit post-quantum security.

Two modes of operation:

• Bundled mode (default): SHA-256-based stubs for API testing. NOT cryptographically secure.
• liboqs mode (SIGNET_HAS_LIBOQS): Real NIST-standardized Kyber-768.

See also

HybridKem for combined Kyber-768 + X25519 key exchange

DilithiumSign for post-quantum digital signatures

Definition at line 663 of file post_quantum.hpp.

Member Function Documentation

decapsulate()

static expected< std::vector< uint8_t > > signet::forge::crypto::KyberKem::decapsulate ( const uint8_t *  ciphertext, size_t  ct_size, const uint8_t *  secret_key, size_t  sk_size  )

inlinestatic

Recover the shared secret from ciphertext + secret key (decapsulation).

The recipient calls this with the received ciphertext and their secret key.

Parameters

ciphertext	Pointer to the ciphertext from encapsulate().
ct_size	Must equal CIPHERTEXT_SIZE (1088 bytes).
secret_key	Pointer to the recipient's Kyber-768 secret key.
sk_size	Must equal SECRET_KEY_SIZE (2400 bytes).

Returns

32-byte shared secret (identical to the sender's).

Definition at line 898 of file post_quantum.hpp.

encapsulate()

static expected< EncapsulationResult > signet::forge::crypto::KyberKem::encapsulate ( const uint8_t *  public_key, size_t  pk_size  )

inlinestatic

Generate a shared secret from a recipient's public key (encapsulation).

The sender calls this with the recipient's public key.

Parameters

public_key	Pointer to the recipient's Kyber-768 public key.
pk_size	Must equal PUBLIC_KEY_SIZE (1184 bytes).

Returns

Ciphertext (to send) + shared secret (to use as AES-256 key).

Definition at line 785 of file post_quantum.hpp.

generate_keypair()

static expected< KeyPair > signet::forge::crypto::KyberKem::generate_keypair ( )

inlinestatic

Generate a Kyber-768 keypair.

Returns

KeyPair with public_key (1184 bytes) and secret_key (2400 bytes), or an error on failure.

Definition at line 715 of file post_quantum.hpp.

Member Data Documentation

CIPHERTEXT_SIZE

constexpr size_t signet::forge::crypto::KyberKem::CIPHERTEXT_SIZE = 1088

staticconstexpr

Kyber-768 ciphertext size (stub default).

Definition at line 678 of file post_quantum.hpp.

PUBLIC_KEY_SIZE

constexpr size_t signet::forge::crypto::KyberKem::PUBLIC_KEY_SIZE = 1184

staticconstexpr

Kyber-768 public key size (stub default).

Definition at line 676 of file post_quantum.hpp.

SECRET_KEY_SIZE

constexpr size_t signet::forge::crypto::KyberKem::SECRET_KEY_SIZE = 2400

staticconstexpr

Kyber-768 secret key size (stub default).

Definition at line 677 of file post_quantum.hpp.

SHARED_SECRET_SIZE

constexpr size_t signet::forge::crypto::KyberKem::SHARED_SECRET_SIZE = 32

staticconstexpr

Shared secret size (256 bits, for AES-256).

Definition at line 679 of file post_quantum.hpp.

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The documentation for this class was generated from the following file:

• include/signet/crypto/post_quantum.hpp