tree 88158d5431957ea83d632eb83cbd46643abd3df1
parent 74e2cd088c962804c0b81807479fb20bf42c7dec
author Jaeden Amero <jaeden.amero@arm.com> 1530116443 +0100
committer itayzafrir <itay.zafrir@arm.com> 1536758690 +0300

psa_export_key: Always set a valid data length

Make psa_export_key() always set a valid data_length when exporting,
even when there are errors. This makes the API easier to use for buggy
programs (like our test code).

Our test code previously used exported_length uninitialized when
checking to see that the buffer returned was all zero in import_export()
in the case where an error was returned from psa_export_key().
Initialize exported_length to an invalid length, and check that it gets
set properly by psa_export_key(), to avoid this using export_length
uninitialized. Note that the mem_is_zero() check is still valid when
psa_export_key() returns an error, e.g. where exported_length is 0, as
we want to check that nothing was written to the buffer on error.

Out test code also previous passed NULL for the data_length parameter of
psa_export_key() when it expected a failure (in key_policy_fail()).
However, data_length is not allowed to be NULL, especially now that we
write to data_length from psa_export_key() even when there are errors.
Update the test code to not pass in a NULL data_length.