Add a test case to ensure `mbedtls_mpi_exp_mod` fails when using a key size
larger than MBEDTLS_MPI_MAX_SIZE.
Add a test case to ensure that Diffie-Hellman operations fail when using a key
size larger than MBEDTLS_MPI_MAX_SIZE.
Signed-off-by: Chris Jones <christopher.jones@arm.com>
A bug in the dhm_check_range() function makes it pass even when the
parameters are not in the range. This commit adds tests for signalling
this problem as well as a couple of other negative tests.