DH

class pyflocker.ciphers.backends.cryptography_.DH.DHParameters(key_size: int | None, generator: int = 2, _params: DHParameters | None = None)

Bases: BaseDHParameters

property g: int

The generator value.

property p: int

The prime modulus value.

property q: int | None

The p subgroup order value.

private_key() → DHPrivateKey

Create a DH private key from the parameters.

Returns:

A private key object.

serialize(encoding: str = 'PEM', format: str = 'PKCS3') → bytes

Serialize the DH parameters.

Parameters:

• encoding – The encoding can be PEM or DER. Defaults to PEM.

• format – The format. Defaults to PKCS3.

Returns:

The parameters encoded as bytes object.

Raises:

ValueError – if the encoding of format is invalid.

classmethod load(data: bytes) → DHParameters

Deserialize the encoded DH parameters.

Parameters:

data – The parameters as an encoded bytes object.

Returns:

DH parameter object.

classmethod load_from_parameters(p: int, g: int = 2, q: int | None = None) → DHParameters

Generates a DH parameter group from the parameters.

Parameters:

• p – The prime modulus value.

• g – The generator value. Must be 2 or 5. Default is 2.

• q – p subgroup order value. Defaults to None.

Returns:

DH Parameter object.

class pyflocker.ciphers.backends.cryptography_.DH.DHPrivateKey(key: DHPrivateKey)

Bases: BaseDHPrivateKey

parameters() → DHParameters

Creates a new DH Parameters object from the key.

Returns:

The DH parameter object.

property key_size: int

Size of the key, in bytes.

public_key() → DHPublicKey

Create a public key from the private key.

Returns:

A public key object.

exchange(peer_public_key: bytes | DHPublicKey | BaseDHPublicKey) → bytes

Perform a key exchange.

Parameters:

peer_public_key – The peer public key can be a bytes or a BaseDHPublicKey object.

Returns:

A shared key.

Raises:

TypeError – if peer_public_key is not a bytes-like or DH Public Key object.

serialize(encoding: str = 'PEM', format: str = 'PKCS8', passphrase: bytes | None = None) → bytes

Serialize the private key.

Parameters:

• encoding – The encoding to use.

• format – The format to use.

• passphrase – The passphrase to use to protect the private key. None if the private key is not encrypted.

Returns:

The private key as bytes object.

Raises:

• ValueError – if the encoding or format is invalid.

• TypeError – if the passphrase is not a bytes-like object.

Important

The encoding and format supported by one backend may not be supported by the other. You should check the documentation of the implementation of this method for supported options.

property x: int

The private value.

classmethod load(data: bytes, passphrase: bytes | None = None) → DHPrivateKey

Deserialize and load the the private key.

Parameters:

• data – The serialized private key as bytes-like object.

• passphrase – The passphrase that was used to protect the private key. If key is not protected, passphrase is None.

Returns:

A private key.

Raises:

• ValueError – If the key could not be deserialized.

• TypeError – If passphrase is not a bytes-like object.

class pyflocker.ciphers.backends.cryptography_.DH.DHPublicKey(key: DHPublicKey)

Bases: BaseDHPublicKey

parameters() → DHParameters

Creates a new DH parameters object from the key.

Returns:

The DH parameter object.

property key_size: int

Size of the key, in bytes.

serialize(encoding: str = 'PEM', format: str = 'SubjectPublicKeyInfo') → bytes

Serialize the public key.

Parameters:

• encoding – The encoding to use. It can be PEM or DER.

• format – The format can be SubjectPublicKeyInfo only.

Returns:

The public key as bytes object.

Raises:

ValueError – if the encoding or format is invalid.

property y: int

The public value.

classmethod load(data: bytes) → DHPublicKey

Deserialize and load the public key.

Parameters:

data – The serialized public key as bytes-like object.

Returns:

A public key object.

Raises:

ValueError – If the key could not be deserialized.

pyflocker.ciphers.backends.cryptography_.DH.generate(key_size: int, g: int = 2) → DHParameters

Generate DHE parameter with prime number’s bit size bits and generator g (default 2). Recommended size of bits > 1024.

Parameters:

• key_size – The bit length of the prime modulus.

• g – The value to use as a generator value. Default is 2.

Returns:

A DH key exchange paramenter object.

pyflocker.ciphers.backends.cryptography_.DH.load_from_parameters(p: int, g: int = 2, q: int | None = None) → DHParameters

Create a DH Parameter object from the given parameters.

Parameters:

• p – The prime modulus p as int.

• g – The generator.

• q – p subgroup order value.

Returns:

A DH key exchange paramenter object.

pyflocker.ciphers.backends.cryptography_.DH.load_parameters(data: bytes) → DHParameters

Deserialize the DH parameters and load a parameter object.

Parameters:

data – Serialized DH Parameter.

Returns:

A parameter object.

pyflocker.ciphers.backends.cryptography_.DH.load_public_key(data: bytes) → DHPublicKey

Loads the public key and returns a Key interface.

Parameters:

data – The public key (a bytes-like object) to deserialize.

Returns:

A public key object.

pyflocker.ciphers.backends.cryptography_.DH.load_private_key(data: bytes, passphrase: bytes | None = None) → DHPrivateKey

Loads the private key and returns a private key object.

If the private key was not encrypted duting the serialization, passphrase must be None, otherwise it must be a bytes-like object.

Parameters:

• data – The private key (a bytes-like object) to deserialize.

• passphrase – The passphrase (in bytes) that was used to encrypt the private key. None if the key was not encrypted.

Returns:

A private key object.