On Fri, Feb 23, 2024 at 03:41:39PM -0500, Stefan Berger wrote: > This series adds support for the NIST P521 curve to the ecdsa module. > > An issue with the current code in ecdsa is that it assumes that input > arrays providing key coordinates for example, are arrays of digits > (a 'digit' is a 'u64'). This works well for all currently supported > curves, such as NIST P192/256/384, but does not work for NIST P521 where > coordinates are 8 digits + 2 bytes long. So some of the changes deal with > converting byte arrays to digits and adjusting tests on input byte > array lengths to tolerate arrays not providing multiples of 8 bytes. Don't you also need to amend software_key_query()? In the "issig" case, it calculates len = crypto_sig_maxsize(sig), which is 72 bytes for P521, then further below calculates "info->max_sig_size = 2 * (len + 3) + 2;" I believe the ASN.1 encoded integers are just 66 bytes instead of 72, so info->max_sig_size is 6 bytes too large. Am I missing something? Thanks, Lukas
