HQC

How to use the crypto_condor.primitives.HQC module to test implementations of HQC.

Test encapsulation

Attention

Testing encapsulation requires a reference implementation to decapsulate the ciphertexts, as encapsulation is a non-deterministic operation. We are working on integrating one.

Test decapsulation

crypto_condor.primitives.HQC.test_decaps(decaps, paramset, *, compliance=True, resilience=False)

Tests decapsulation.

Uses the given function to decapsulate ciphertexts and compares the resulting shared secret with the test vectors. The test passes if the secrets match.

Parameters:

  • decaps (Decaps) – The decapsulation function.

  • paramset (Paramset) – The parameter set to use.

Keyword Arguments:

  • compliance – Whether to use compliance test vectors.

  • resilience – Whether to use resilience test vectors.

Returns:

A dictionary of results, with one Results per test vectors file.

Return type:

ResultsDict

Test the encapsulation-decapsulation invariant

crypto_condor.primitives.HQC.test_invariant(encaps, decaps, paramset)

Tests the encapsulate then decapsulate invariant.

Encapsulating to a public key then decapsulating with the corresponding secret key should always yield the same share secret. To test this invariant, crypto-condor uses key pairs from test vectors to perform both operations. The test passes if the shared secrets match.

Parameters:

  • encaps (Encaps) – The encapsulation function.

  • decaps (Decaps) – The decapsulation function.

  • paramset (Paramset) – The parameter set to test.

Returns:

A dictionary of results with one Results per test vectors file.

Return type:

ResultsDict

Notes

Only valid keys from compliance test vectors are used.

Parameters

enum crypto_condor.primitives.HQC.Paramset(value)

HQC parameter sets.

Member Type:

str

Valid values are as follows:

HQC128 = <Paramset.HQC128: 'HQC-128'>
HQC192 = <Paramset.HQC192: 'HQC-192'>
HQC256 = <Paramset.HQC256: 'HQC-256'>

The Enum and its members also have the following methods:

property pk_size

The size of the public key in bytes.

property sk_size

The size of the secret key in bytes.

property ct_size

The size of the ciphertext in bytes.

property ss_size

The size of the shared secret in bytes.

Protocols

protocol crypto_condor.primitives.HQC.Encaps

Represents an HQC encapsulation function.

Classes that implement this protocol must have the following methods / attributes:

__call__(pk)

Generates and encapsulates a shared secret.

Parameters:

pk (bytes) – The public key to encapsulate the secret with.

Returns:

A tuple (ct, ss) containing the shared secret (ss) and ciphertext (ct).

Return type:

tuple[bytes, bytes]

protocol crypto_condor.primitives.HQC.Decaps

Represents an HQC decapsulation function.

Classes that implement this protocol must have the following methods / attributes:

__call__(sk, ct)

Decapsulates a shared secret.

Parameters:

  • sk (bytes) – The secret key to use.

  • ct (bytes) – The ciphertext to decapsulate.

Returns:

The decapsulated shared secret.

Return type:

bytes