[TLS] Channel binding versus keying material exporters

Douglas Stebila <douglas@stebila.ca> Thu, 05 November 2009 16:22 UTC

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From: Douglas Stebila <douglas@stebila.ca>
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Subject: [TLS] Channel binding versus keying material exporters
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Can someone comment on the similarities and differences of TLS channel  
binding and TLS keying material exporters?  Is the keying material  
derived from a TLS master key using a keying material exporter  
suitable for channel binding as well, if used for key confirmation?   
If a higher-level application wishes to do additional authentication  
and bind the endpoints of that authentication to the endpoints of the  
TLS connection, should one use key confirmation with keying material  
exporters or something from TLS channel binding?

Thanks,

Douglas