On Fri, 2024-02-16 at 14:32 -0500, Stefan Berger wrote: > > On 2/16/24 14:27, Simo Sorce wrote: > > On Thu, 2024-02-15 at 18:13 -0500, Stefan Berger wrote: > > > This series of patches adds support for the NIST P521 curve to ecdsa and > > > ecdh. Test cases for NIST P521 are added to both modules. > > > > > > An issue with the current code in ecdsa and ecdh 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 digits to byte arrays. > > > > > > > > > Regards, > > > Stefan > > > > > > v2: > > > - Reformulated some patch descriptions > > > - Fixed issue detected by krobot > > > - Some other small changes to the code > > > > > > Stefan Berger (14): > > > crypto: ecdsa - Convert byte arrays with key coordinates to digits > > > crypto: ecdsa - Adjust tests on length of key parameters > > > crypto: ecdsa - Extend res.x mod n calculation for NIST P521 > > > crypto: ecc - Implement vli_mmod_fast_521 for NIST p521 > > > crypto: ecc - For NIST P521 use vli_num_bits to get number of bits > > > crypto: ecc - Add NIST P521 curve parameters > > > crypto: ecdsa - Register NIST P521 and extend test suite > > > x509: Add OID for NIST P521 and extend parser for it > > > crypto: ecdh - Use properly formatted digits to check for valid key > > > crypto: ecc - Implement ecc_digits_to_bytes to convert digits to byte > > > array > > > crypto: Add nbits field to ecc_curve structure > > > crypto: ecc - Implement and use ecc_curve_get_nbytes to get curve's > > > nbytes > > > crypto: ecdh - Use functions to copy digits from and to byte array > > > crypto: ecdh - Add support for NIST P521 and add test case > > > > > > crypto/asymmetric_keys/x509_cert_parser.c | 3 + > > > crypto/ecc.c | 71 +++++-- > > > crypto/ecc_curve_defs.h | 45 +++++ > > > crypto/ecdh.c | 59 +++++- > > > crypto/ecdsa.c | 48 ++++- > > > crypto/testmgr.c | 14 ++ > > > crypto/testmgr.h | 225 ++++++++++++++++++++++ > > > include/crypto/ecc_curve.h | 3 + > > > include/crypto/ecdh.h | 1 + > > > include/crypto/internal/ecc.h | 61 +++++- > > > include/linux/oid_registry.h | 1 + > > > 11 files changed, 495 insertions(+), 36 deletions(-) > > > > Hi Stefan, > > what kind of side-channel testing was performed on this code? > > And what is the use case you are adding it for? > > We're using public keys for signature verification. I am not aware that > public key usage is critical to side channels. > > The use case for adding it is primarily driven by closing a gap to > complete the support for the common ECDSA NIST curves. Is there an assumption the ECDH code uses exclusively ephemeral keys? Simo. -- Simo Sorce Distinguished Engineer RHEL Crypto Team Red Hat, Inc
