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File: //usr/lib/python3/dist-packages/twisted/conch/ssh/__pycache__/_kex.cpython-310.pyc
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SSH key exchange handling.
�)�sha1�sha256�sha384�sha512)�	Attribute�	Interface�implementer)�errorc@� eZdZdZed�Zed�ZdS)�_IKexAlgorithmzB
    An L{_IKexAlgorithm} describes a key exchange algorithm.
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    An L{_IFixedGroupKexAlgorithm} describes a key exchange algorithm with a
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    zdAn L{int} giving the prime number used in Diffie-Hellman key exchange, or L{None} if not applicable.z�An L{int} giving the generator number used in Diffie-Hellman key exchange, or L{None} if not applicable. (This is not related to Python generator functions.)N)rr
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    An L{_IEllipticCurveExchangeKexAlgorithm} describes a key exchange algorithm
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    An L{_IGroupExchangeKexAlgorithm} describes a key exchange algorithm
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    Nrrrrrr;rrc@�eZdZdZdZeZdS)�_Curve25519SHA256z�
    Elliptic Curve Key Exchange using Curve25519 and SHA256. Defined in
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    As L{_Curve25519SHA256}, but with a pre-standardized algorithm name.
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    Elliptic Curve Key Exchange with SHA-256 as HASH. Defined in
    RFC 5656.

    Note that C{ecdh-sha2-nistp256} takes priority over nistp384 or nistp512.
    This is the same priority from OpenSSH.

    C{ecdh-sha2-nistp256} is considered preety good cryptography.
    If you need something better consider using C{curve25519-sha256}.
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    Elliptic Curve Key Exchange with SHA-384 as HASH. Defined in
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rrrrrrrrrr%kr r%c@r)�_ECDH512zT
    Elliptic Curve Key Exchange with SHA-512 as HASH. Defined in
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rrrrrrrrrr'vr r'c@r)�_DHGroupExchangeSHA256zc
    Diffie-Hellman Group and Key Exchange with SHA-256 as HASH. Defined in
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    Diffie-Hellman Group and Key Exchange with SHA-1 as HASH. Defined in
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    Diffie-Hellman key exchange with SHA-1 as HASH and Oakley Group 14
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r-)�curve25519-sha256scurve25519-sha256@libssh.orgs$diffie-hellman-group-exchange-sha256s"diffie-hellman-group-exchange-sha1sdiffie-hellman-group14-sha1secdh-sha2-nistp256secdh-sha2-nistp384secdh-sha2-nistp521cCs |tvrt�d|����t|S)aY
    Get a description of a named key exchange algorithm.

    @param kexAlgorithm: The key exchange algorithm name.
    @type kexAlgorithm: L{bytes}

    @return: A description of the key exchange algorithm named by
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    @rtype: L{_IKexAlgorithm}

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    Returns C{True} if C{kexAlgorithm} is an elliptic curve.

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    Returns C{True} if C{kexAlgorithm} has a fixed prime / generator group.

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    @type kexAlgorithm: L{bytes}

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    @rtype: L{bool}
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    Get the hash algorithm callable to use in key exchange.

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    @return: A callable hash algorithm constructor (e.g. C{hashlib.sha256}).
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    Get the generator and the prime to use in key exchange.

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    @rtype: L{tuple}
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    Get a list of supported key exchange algorithm names in order of
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