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SignatureValue for ECDSA is not well defined enough #28

Closed emanjon closed 4 years ago

emanjon commented 4 years ago

The text just states that extra padding and additional lengths are removed....

highlunder commented 4 years ago

Ok! I'm not sure what would be the best place to expand the explanation further.

For someone looking at our sample certificate, they will find that the asn1-signature parses like this:

30 44 02 20 373873EF8781B88297EF235C1FACCF62DA4E44740DC2A2E6A3C6C882A3238D9C 02 20 3AD9353BA788683B06BB48FECA16EA71171734C675C5332B2AF1CB733810A1FC

Out of which only the raw data is kept, since the length of the signature fields are known by the algorithms.

--> 373873EF8781B88297EF235C1FACCF62DA4E44740DC2A2E6A3C6C882A3238D9C + 3AD9353BA788683B06BB48FECA16EA71171734C675C5332B2AF1CB733810A1FC

emanjon commented 4 years ago

Need to describe that the r and s are encoded as 32, 48, 66 bytes each . The X.509 encoding is variable lenght. Following (padding and extra length fields which are present in the ASN.1 encoding are omitted) in a similar way as for the serialnumber is not reversable.

emanjon commented 4 years ago

Fixed in last submission