Corresponds better to the validation done in other modules of PSA Crypto.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
As we want to do Mbed TLS aead operations as a
driver does, aead operations should not access
the key slot as key slots are not available to
drivers.
Second step in this PR: do not unlock the key slot
as part of operation abort.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
As we want to do Mbed TLS aead operations as a
driver does, aead operations should not access
the key slot as key slots are not available to
drivers.
First step in this PR: move key resolution from
aead operation setup to psa_aead_encrypt/decrypt
APIs.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
This check was added earlier to avoid useless calls to `memcpy()`
with length `0` in the _frequent_ case where we're not accumulating.
By now, the whole code path has been moved to a branch which is only
executed if the reader is accumulating, and the only time this check
would be relevant is if we happen to feed an empty fragment to the
reader. In this case, the call to memcpy() could be removed, but
since this case is exceptional and the call to memcpy() is still
correct even for a length 0 copy, we remove the check for simplicity
of the code.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
Previously, the semantics of mbedtls_mps_reader_commit() was to invalidate
all buffers previously fetched via mbedtls_mps_reader_get(), forbidding
any further use by the 'consumer'. This was in fact a necessary constraint
for the current implementation, which did some memory moving in
mbedtls_mps_reader_commit().
This commit simplifies the reader's semantics and implementation in
the following way:
- API: A call to mbedtls_mps_reader_commit() does no longer invalidate
the buffers previously obtained via mbedtls_mps_reader_get().
Instead, they can continue to be used until
mbedtls_mps_reader_reclaim() is called.
Calling mbedtls_mps_reader_commit() now only sets a marker
indicating which parts of the data received through
mbedtls_mps_reader_get() need not be backed up once
mbedtls_mps_reader_reclaim() is called. Allowing the user
to call mbedtls_mbedtls_reader_commit() multiple times
before mbedtls_mps_reader_reclaim() is mere convenience:
We'd get exactly the same functionality if instead of
mbedtls_mps_reader_commit(), there was an additional argument
to mbedtls_mps_reader_reclaim() indicating how much data
to retain. However, the present design is more convenient
for the user and doesn't appear to introduce any unnecessary
complexity (anymore), so we stick with it for now.
- Implementation: mbedtls_mps_reader_commit() is now a 1-liner,
setting the 'commit-marker', but doing nothing else.
Instead, the complexity of mbedtls_mp_reader_reclaim()
slightly increases because it has to deal with creating
backups from both the accumulator and the current
fragment. In the previous implementation, which shifted
the accumulator content with every call to
mbedtls_mps_reader_commit(), only the backup from the
fragment was necessary; with the new implementation
which doesn't shift anything in
mbedtls_mps_reader_commit(), we need to do the
accumulator shift in mbedtls_mps_reader_reclaim().
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
This commit adds an implementation of the MPS trace module
based on `printf()`.
The enabling macro MBEDTLS_MPS_TRACE remains unset by default
because MPS tracing is very verbose and consumes unnecessary
space in the CI.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
This commit adds an internal header `library/mps/error.h` related
to error codes in MPS.
For now, those error codes can be considered internal and thus we
don't have to avoid clashes with other Mbed TLS error codes. This
is OK as long as it's true that MPS isn't public API, and its error
codes are never forwarded to the return values of public API calls.
The error code allocation of MPS will likely need revisiting over time.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
Most buffers that MPS deals with are small and representable
with integer types of width 16-bit or more.
For highly memory constrained systems, it is therefore a potential
for significant memory savings to use 16-bit types for buffer sizes
throughout MPS.
In prepraration for this, this commit introduces typdefs
```
mbedtls_mps_size_t
mbedtls_mps_stored_size_t
```
for buffer sizes in the MPS implementation and the MPS structures,
respectively.
So far, those MUST be defined as `size_t`: While an effort has been made
to write most of MPS code in terms of `mbedtls_mps_[stored_]size_t` in a
way that would allow narrower types, those aren't yet supported. Still,
we retain the typedefs in order to avoid unnecessary rewriting of a large
body of the MPS codebase.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
This commit adds the interface fo the MPS reader component as
`library/mps/reader.h`.
Please see the file itself for extensive documentation.
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
