[Trans] RFC6962 BIS Log file encodings.

Phillip Hallam-Baker <hallam@gmail.com> Thu, 13 March 2014 17:29 UTC

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From: Phillip Hallam-Baker <hallam@gmail.com>
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Subject: [Trans] RFC6962 BIS Log file encodings.
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I am trying to make sense of the log file encoding (section 3). this does
not seem to me to be properly or clearly specified.

RFC6962 punts the encoding question to RFC5246 but this only helps somewhat
because the description there is atrocious.

In particular it is implicit in the text that digitaly-signed is equivalent
to the ASN.1 macro. But this isn't actually explained anywhere in section 4
of 5246. So as a result there is no information on where the signature
appears in the data stream, does it precede or follow the signed data?

This is quite problematic because in the TLS use the signed data does not
appear on the wire at all, the construct is used in client auth when the
prior handshake is signed so there is no need to retransmit the data.

It looks to me like the idea here is that the SCT does not need to include
the certificate or precertificate data because the corresponding signed
data will always be implicit from the mode of use. But that needs to be
clearly stated.

At the moment the specification is assuming that the reader has a high
degree of familiarity with PKIX and TLS encodings and can switch gear
between them.

Website: http://hallambaker.com/