On space-constrained platforms, it is a useful configuration to be able
to import/export and perform RSA key pair operations, but to exclude RSA
key generation, potentially saving flash space. It is not possible to
express this with the PSA_WANT_ configuration system at the present
time. However, in previous versions of Mbed TLS (v2.24.0 and earlier) it
was possible to configure a software PSA implementation which was
capable of making RSA signatures but not capable of generating RSA keys.
To do this, one unset MBEDTLS_GENPRIME.
Since the addition of MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR, this
expressivity was lost. Expressing that you wanted to work with RSA key
pairs forced you to include the ability to generate key pairs as well.
Change psa_crypto_rsa.c to only call mbedtls_rsa_gen_key() if
MBEDTLS_GENPRIME is also set. This restores the configuration behavior
present in Mbed TLS v2.24.0 and earlier versions.
It left as a future exercise to add the ability to PSA to be able to
express a desire for a software or accelerator configuration that
includes RSA key pair operations, like signature, but excludes key pair
generation.
Without this change, linker errors will occur when attempts to call,
which doesn't exist when MBEDTLS_GENPRIME is unset.
psa_crypto_rsa.c.obj: in function `rsa_generate_key':
psa_crypto_rsa.c:320: undefined reference to `mbedtls_rsa_gen_key'
Fixes#4512
Signed-off-by: Jaeden Amero <jaeden.amero@arm.com>
The test "PSA generate key: RSA, 1024 bits, good, encrypt (OAEP
SHA-256)" had a dependency on MBEDTLS_GENPRIME, but this was not listed
in the dependencies. Add MBEDTLS_GENPRIME to the test's dependencies to
ensure it has what it needs to run.
Signed-off-by: Jaeden Amero <jaeden.amero@arm.com>
Since they became equivalent after moving the is_sign checking back to
the PSA core, they're now redundant, and the generic mac_setup function
can just be called directly.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Since a valid mac operation context would guarantee that the stored
mac size is >= 4, it wasn't immediately obvious that the zero-length
check is meant for static analyzers and a bit of robustness.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
The PSA core checks the key type and algorithm combination before
calling the driver, so the driver doesn't have to do this once more.
The PSA core will also not start an operation with a requested length
which is larger than the full MAC output size, so the output length check
in the driver isn't needed as long as the driver returns an error on
mac_setup if it doesn't support the underlying hash algorithm.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
It makes sense to do the length checking in the core rather than expect
each driver to deal with it themselves. This puts the onus on the core to
dictate which algorithm/key combinations are valid before calling a driver.
Additionally, this commit also updates the psa_mac_sign_finish function
to better deal with output buffer sanitation, as per the review comments
on #4247.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
This configuration file was useful in the early days of PSA crypto
development. It stopped becoming relevant when MBEDTLS_PSA_CRYPTO_C entered
the default configuration. Remove it: better late than never.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
To avoid the MAC tests from being run when only part of the driver
wrappers (not including MAC) are being configured for test.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
As psa_mac_sign_finish / psa_mac_verify_finish already checks that the
operation structure is valid (id is non-zero), the driver itself doesn't
have to check for that anymore. If the operation has a driver ID assigned,
it means that driver has returned success from its setup function, so the
algorithm value will be set correctly.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
The key passed to the driver has been imported by the PSA Core, meaning
its length has already been verified, and the driver can rely on the
buffer length and key attributes being consistent.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
This means there is no longer a need to have an internal HMAC API, so
it is being removed in this commit as well.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Prefix with 'mbedtls_psa' as per the other types which implement some
sort of algorithm in software.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Now renamed to mbedtls_psa_safer_memcmp, it provides a single location
for buffer comparison.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
The purpose of key_set was to guard the operation structure from being
used for update/finish before a key was set. Now that the implementation
fully adheres to the PSA API, that function is covered by the `alg`
variable instead. It's set to the algorithm in use when a key is set, and
is zero when the operation is reset/invalid.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
* Early return since there's nothing to clean up
* Get rid of unnecessary local variable
* Check algorithm validity for MAC in the PSA core instead of in the driver
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Apparently it was at some point assumed that there would be
support for MAC algorithms with IV, but that hasn't been
implemented yet. Until that time, these context structure
members are superfluous and can be removed.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Typedef'ed structures are suffixed _t
Also updated the initialiser macro with content that actually
matches the structure's content.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Since HMAC moved into its own compilation unit, the internal API needed
to be documented and finalized. This means no more reaching deep into
the operation structure from within the PSA Crypto core. This will make
future refactoring work easier, since internal HMAC is now opaque to the
core.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Step 3/x in moving the driver. Separate commits should make for easier
review.
Additional changes on top of code movement:
* Copied the implementation of safer_memcmp from psa_crypto into
psa_cipher_mac since the mac_verify driver implementation
depends on it, and it isn't available through external linkage
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Step 2/x in moving the driver. Separate commits should make for easier
review.
Additional changes on top of code movement:
* Early-return success on input with zero-length to mac_update, to
avoid NULL pointers getting passed into the driver dispatch
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Step 1/x in moving the driver. Separate commits should make for easier
review.
Additional changes on top of just moving code:
* Added a sanity check on the key buffer size for CMAC.
* Transfered responsibility for resetting the core members of the
PSA MAC operation structure back to the core (from the driver
wrapper layer)
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
This is a temporary measure. Other operations in the PSA Core which rely
on this internal HMAC API should be rewritten to use the MAC API instead,
since they can then leverage accelerated HMAC should a platform provide
such acceleration support.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Modeled after the include chain of the primitive operation contexts.
Also moved the HMAC context structure to the builtin composites file,
since that is where it conceptually belongs. This is a preparatory
step for implementing driver dispatch of MAC multipart operations.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
