The value was overwritten and the length wasn't used either. This latter
could have lead to a buffer overflow as well.
Signed-off-by: Janos Follath <janos.follath@arm.com>
The external representation before included more than just endianness
(like reading in Mongtomery curve scalars or converting hashes to
numbers in a standard compliant way).
These are higher level concepts and are out of scope for Bignum and for
the modulus structure.
Signed-off-by: Janos Follath <janos.follath@arm.com>
In theory we could allow residues to have more allocated limbs than the
modulus, but we might or might not need it in the end.
Go for the simpler option for now and we can extend it later if we
really need it.
Signed-off-by: Janos Follath <janos.follath@arm.com>
We want to make sure that the value has at least as many limbs allocated
as the modulus as we need this to be able to do any operations in
constant time.
An invariant of the API is that the residue values are canonical, make
sure that the residue is compared to the entire modulus.
Signed-off-by: Janos Follath <janos.follath@arm.com>
This patch adjusts the logic of the size checking of the method,
and refactors the tests. Documentation has also been updated.
Signed-off-by: Minos Galanakis <minos.galanakis@arm.com>
This patch is inverting the input type checking logic in the method,
in order to ensure that residue < modulus.
Signed-off-by: Minos Galanakis <minos.galanakis@arm.com>
This patch adds the following tests for the high levet IO api:
* mpi_mod_io_neg
* mpi_mod_io
Manually generated test data has also been included.
Signed-off-by: Minos Galanakis <minos.galanakis@arm.com>
Legacy Bignum is excluded as it doesn't get regular extensions like new
ones.
Each slot uses comments of their respective filetype. Since .data files
don't have a syntax for comments, dummy test cases are used. (These test
cases will never be executed and no noise will be added to tests.)
Signed-off-by: Janos Follath <janos.follath@arm.com>