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COSE Working Group Issues
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"y > 0" should be "y >= 0" #45

Closed selfissued closed 8 years ago

selfissued commented 8 years ago

Section 13.1.1 (Double Coordinate Curves) of draft -08 contains this text: When encoding the sign of y, the expression 'y > 0' is evaluated and encoded a CBOR boolean.

Given that the sign bit of a zero value is 0, I suspect that should actually be "y >= 0" so that it evaluates to true for all values with a zero sign bit.

jimsch commented 8 years ago

I need to find the correct reference, but I believe that if y is zero then you have a bad point.

selfissued commented 8 years ago

I believe that this is true for some curves, but even if so, the "y >= 0" would be correct both for curves that allow 0 and those that don't.

jimsch commented 8 years ago

Fixed in pull cose-wg/cose-spec#105

jimsch commented 8 years ago

Changed to use the SEC1 algorithm instead of trying to make it easy.

selfissued commented 8 years ago

This looks good now. Thanks.