mpi_core_random_basic and mpi_random_values must generate the same random
sequences in order to get the expected test coverage (where we know we'll
hit certain numbers of retries). Facilitate this by defining the RNG seed
only once.
Fix the seed to explicitly list all 16 words of the key. This isn't strictly
required (missing initializer fields get the value zero), but it's clearer.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
The random-in-nrange test code has auxiliary functions that are common to all
the interfaces (core, mod_raw (upcoming), mod (upcoming), legacy), and does
some differential testing to check that all the layers consume the RNG in
the saame way. Test them all in the same test suite.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Test some cases where mbedtls_mpi_core_random() or mbedtls_mpi_random()
should return MBEDTLS_ERR_MPI_NOT_ACCEPTABLE. These test cases use a very
small range that makes the NOT_ACCEPTABLE case likely. The test code uses a
deterministic RNG whose implementation is in the test framework, so we know
that the tests will pass reproducibly unless the implementation the test
framework changes.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
The test function mpi_random_many() is the main function for testing the
get-random-in-range function. It validates that the random generator's
output is within the desired range, and performs some basic statistical
checks including checking that small ranges are covered exhaustively.
Switch this function from testing mbedtls_mpi_random() to testing
mbedtls_mpi_core_random(). This does not reduce the test coverage of
mbedtls_mpi_random() because the same properties are now validated
indirectly via mpi_random_values() which checks that mbedtls_mpi_random()
and mbedtls_mpi_core_random() produce identical values for identical inputs.
As of this commit, mpi_random_many() still uses some legacy mpi functions
internally because the corresponding functions don't exist yet in core.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
For good cases, test that mbedtls_mpi_random() produces the same output as
mbedtls_mpi_core_random().
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Shuffle things around a bit inside mbedtls_mpi_random() in preparation for
breaking out mbedtls_mpi_core_random().
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Rewrite the minimum bound comparison to avoid a local allocation. This costs
a bit of code size, but saves RAM. This is in preparation for moving the
bulk of the function to the bignum_core module where allocation is not
permitted.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Compare a single-limb MPI with a multi-limb MPI. This is rather ad hoc, but
will be useful for mbedtls_mpi_core_random.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
If the variable SKIP_TEST_SUITES is not defined with -D, but is defined
in an environment variable, tell cmake to get it from there.
Signed-off-by: David Horstmann <david.horstmann@arm.com>