When ECDSA is not supported by the library, prefer
to return NOT_SUPPORTED than INVALID_ARGUMENT when
asked for an ECDSA signature.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Move the check that ECDSA is supported from the
caller of the function responsible for Mbed TLS
ECDSA signatures to this function, namely
mbedtls_psa_ecdsa_sign_hash().
This makes the caller code more readable and is
more aligned with what is expected from a
sign_hash() PSA driver entry point.
Add a negative test case where a deterministic
ECDSA signature is requested while the library
does not support deterministic ECDSA.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Attempting to create an ECC key with a curve specification that is not
valid can plausibly fail with PSA_ERROR_INVALID_ARGUMENT ("this is not
a curve specification at all") or PSA_ERROR_NOT_SUPPORTED ("this may
be a curve specification, but not one I support"). The choice of error
is somewhat subjective.
Before this commit, due to happenstance in the implementation, an
attempt to use a curve that is declared in the PSA API but not
implemented in Mbed TLS returned PSA_ERROR_INVALID_ARGUMENT, whereas
an attempt to use a curve that Mbed TLS supports but for which support
was disabled at compile-time returned PSA_ERROR_NOT_SUPPORTED. This
inconsistency made it difficult to write negative tests that could
work whether the curve is implemented via Mbed TLS code or via a
driver.
After this commit, any attempt to use parameters that are not
recognized fails with NOT_SUPPORTED, whether a curve with the
specified size might plausibly exist or not, because "might plausibly
exist" is not something Mbed TLS can determine.
To keep returning INVALID_ARGUMENT when importing an ECC key with an
explicit "bits" attribute that is inconsistent with the size of the
key material, this commit changes the way mbedtls_ecc_group_of_psa()
works: it now works on a size in bits rather than bytes, with an extra
flag indicating whether the bit-size must be exact or not.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Add ECP/RSA transparent test driver import_key
entry point and use it in the transparent test
driver entry supporting both ECP and RSA.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Add ECP/RSA transparent test driver export_public_key
entry point and use it in the transparent test driver
supporting both ECP and RSA.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
