File: //usr/lib/python3/dist-packages/twisted/words/protocols/jabber/__pycache__/sasl.cpython-38.pyc
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XMPP-specific SASL profile.
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Parse the SASL feature to extract the available mechanism names.
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SASL base exception.
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The server did not present an acceptable SASL mechanism.
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SASL Authentication failed.
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r c @ s e Zd ZdZdS )�SASLIncorrectEncodingErrora
SASL base64 encoding was incorrect.
RFC 3920 specifies that any characters not in the base64 alphabet
and padding characters present elsewhere than at the end of the string
MUST be rejected. See also L{fromBase64}.
This exception is raised whenever the encoded string does not adhere
to these additional restrictions or when the decoding itself fails.
The recommended behaviour for so-called receiving entities (like servers in
client-to-server connections, see RFC 3920 for terminology) is to fail the
SASL negotiation with a C{'incorrect-encoding'} condition. For initiating
entities, one should assume the receiving entity to be either buggy or
malevolent. The stream should be terminated and reconnecting is not
advised.
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Decode base64 encoded string.
This helper performs regular decoding of a base64 encoded string, but also
rejects any characters that are not in the base64 alphabet and padding
occurring elsewhere from the last or last two characters, as specified in
section 14.9 of RFC 3920. This safeguards against various attack vectors
among which the creation of a covert channel that "leaks" information.
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Stream initializer that performs SASL authentication.
The supported mechanisms by this initializer are C{DIGEST-MD5}, C{PLAIN}
and C{ANONYMOUS}. The C{ANONYMOUS} SASL mechanism is used when the JID, set
on the authenticator, does not have a localpart (username), requesting an
anonymous session where the username is generated by the server.
Otherwise, C{DIGEST-MD5} and C{PLAIN} are attempted, in that order.
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Select and setup authentication mechanism.
Uses the authenticator's C{jid} and C{password} attribute for the
authentication credentials. If no supported SASL mechanisms are
advertized by the receiving party, a failing deferred is returned with
a L{SASLNoAcceptableMechanism} exception.
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Start SASL authentication exchange.
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z SASLInitiatingInitializer.startc C sJ t �tdf�}| jj|d< |dk r:|�t|��d�p6d� | j� |� dS )z�
Initiate authentication protocol exchange.
If an initial client response is given in C{data}, it will be
sent along.
@param data: initial client response.
@type data: C{str} or L{None}.
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Send response to a challenge.
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Parse challenge and send response from the mechanism.
@param element: the challenge protocol element.
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Clean up observers, reset the XML stream and send a new header.
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Clean up observers, parse the failure and errback the deferred.
@param failure: the failure protocol element. Holds details on
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@type failure: L{domish.Element}
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