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SSH key exchange handling.
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An L{_IKexAlgorithm} describes a key exchange algorithm.
z�An L{int} giving the preference of the algorithm when negotiating key exchange. Algorithms with lower precedence values are more preferred.zqA callable hash algorithm constructor (e.g. C{hashlib.sha256}) suitable for use with this key exchange algorithm.N)�__name__�
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An L{_IFixedGroupKexAlgorithm} describes a key exchange algorithm with a
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An L{_IEllipticCurveExchangeKexAlgorithm} describes a key exchange algorithm
that uses an elliptic curve exchange between the client and server.
N�r r r r r r r r r 4 s r c @ s e Zd ZdZdS )�_IGroupExchangeKexAlgorithmz�
An L{_IGroupExchangeKexAlgorithm} describes a key exchange algorithm
that uses group exchange between the client and server.
A prime / generator group should be chosen at run time based on the
requested size. See RFC 4419.
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Elliptic Curve Key Exchange with SHA-256 as HASH. Defined in
RFC 5656.
� N�r r r r r r r r r r r r G s r c @ s e Zd ZdZdZeZdS )�_ECDH384zT
Elliptic Curve Key Exchange with SHA-384 as HASH. Defined in
RFC 5656.
� N)r r r r r r r r r r r r R s r c @ s e Zd ZdZdZeZdS )�_ECDH512zT
Elliptic Curve Key Exchange with SHA-512 as HASH. Defined in
RFC 5656.
� N)r r r r r r r r r r r r! ] s r! c @ s e Zd ZdZdZeZdS )�_DHGroupExchangeSHA256zc
Diffie-Hellman Group and Key Exchange with SHA-256 as HASH. Defined in
RFC 4419, 4.2.
� Nr r r r r r# h s r# c @ s e Zd ZdZdZeZdS )�_DHGroupExchangeSHA1za
Diffie-Hellman Group and Key Exchange with SHA-1 as HASH. Defined in
RFC 4419, 4.1.
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Diffie-Hellman key exchange with SHA-1 as HASH and Oakley Group 14
(2048-bit MODP Group). Defined in RFC 4253, 8.2.
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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
C{kexAlgorithm}.
@rtype: L{_IKexAlgorithm}
@raises ConchError: if the key exchange algorithm is not found.
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Returns C{True} if C{kexAlgorithm} is an elliptic curve.
@param kexAlgorithm: The key exchange algorithm name.
@type kexAlgorithm: C{str}
@return: 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.
@param kexAlgorithm: The key exchange algorithm name.
@type kexAlgorithm: L{bytes}
@return: C{True} if C{kexAlgorithm} has a fixed prime / generator group,
otherwise C{False}.
@rtype: L{bool}
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Get the hash algorithm callable to use in key exchange.
@param kexAlgorithm: The key exchange algorithm name.
@type kexAlgorithm: L{bytes}
@return: A callable hash algorithm constructor (e.g. C{hashlib.sha256}).
@rtype: C{callable}
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Get the generator and the prime to use in key exchange.
@param kexAlgorithm: The key exchange algorithm name.
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@return: A L{tuple} containing L{long} generator and L{long} prime.
@rtype: L{tuple}
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Get a list of supported key exchange algorithm names in order of
preference.
@return: A C{list} of supported key exchange algorithm names.
@rtype: C{list} of L{bytes}
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