RSA: updating the supported RSA modulo sizes in sigGen and sigVer modes.

[almau]

Protocol Section
https://pages.nist.gov/ACVP/draft-celi-acvp-rsa.html#name-keygen-registration-table-2
https://pages.nist.gov/ACVP/draft-celi-acvp-rsa.html#name-rsa-siggen-fips186-5-capabi
https://pages.nist.gov/ACVP/draft-celi-acvp-rsa.html#name-rsa-sigver-fips186-5-capabi

Protocol Question
FIPS186-4 supports RSA modulos ranging from 2048 to 4096 for all certified modes (keyGen, sigGen, and sigVer):

• keyGen: 2048, 3072 or 4096
• sigGen: 2048, 3072, 4096
• sigVer: 1024, 2048, 3072, 4096

The RSA modulo greater than 4096 is only implemented in keyGen for FIPS186-5:

• keyGen: 2048, 3072, 4096, 6144, or 8192
• sigGen: 2048, 3072, 4096
• sigVer: 2048, 3072, 4096

Are you going to increase the supported modulo sizes for sigGen and sigVer modes to 6144 and 8192 bits?

[jbrock24]

Hi @almau, we don't have any plans on adding support for 6144 or 8192 modulo sizes to RSA SigGen or SigVer. As far as we are concerned, if you test and pass the testable RSA sizes, we trust that the implementation will work for the others.

If you have any further questions regarding this, please feel free to ask. If not, we can close the issue! Thanks for the question!