I wrote a function to determine the base algorithm given a variant,
however this is already implemented by
PSA_ALG_AEAD_WITH_DEFAULT_LENGTH_TAG
Signed-off-by: Paul Elliott <paul.elliott@arm.com>
Introduce psa_mac_compute_internal with an
additional `is_sign` parameter compared to
the psa_mac_compute API. The intent is to
call psa_mac_compute_internal() from
psa_mac_verify() as well to compute the
message MAC.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Re-organize psa_mac_setup() to prepare the move
to a dedicated function of the additional checks
on the algorithm and the key attributes done by
this function. We want to move those checks in
a dedicated function to be able to do them
without duplicating them in psa_mac_compute().
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
This makes it easier to ensure that crypto_spe.h is included everywhere it
needs to be, and that it's included early enough to do its job (it must be
included before any mention of psa_xxx() functions with external linkage,
because it defines macros to rename these functions).
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Implement one-shot MAC APIs, psa_mac_compute and psa_mac_verify, introduced in PSA Crypto API 1.0.
Signed-off-by: gabor-mezei-arm <gabor.mezei@arm.com>
mbedtls_rsa_set_padding() now returns the error
code MBEDTLS_ERR_RSA_INVALID_PADDING when
padding parameters are invalid.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Add comment to the effect that we cannot really check nonce size as the
GCM spec allows almost arbitrarily large nonces. As a result of this,
change the operation nonce over to an allocated buffer to avoid overflow
situations.
Signed-off-by: Paul Elliott <paul.elliott@arm.com>
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>
Removes mode parameter from
mbedtls_rsa_rsaes_oaep_encrypt and propagates
changes throughout the codebase.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
Removal of the mode parameter from
mbedtls_rsa_pkcs1_encrypt function. This change
is propagated throughout the codebase and to
relevant tests.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
Split to data required for internal implementation and data required for
driver implementation with data left over for the PSA layer.
Signed-off-by: Paul Elliott <paul.elliott@arm.com>
To avoid code duplication of the old-style SE interface usage
call psa_driver_wrapper_sign/verify_hash function instead of
the direct internal functions.
Signed-off-by: gabor-mezei-arm <gabor.mezei@arm.com>
Use common funtion for psa_sign_hash and psa_sign_message and one for
psa_verify_hash and psa_verify_message to unify them.
Signed-off-by: gabor-mezei-arm <gabor.mezei@arm.com>
Removing the mode parameter from the mbedtls_rsa_rsaes_oaep_decrypt
function. The change is progagated to all function calls, including in
test suite .function files. Additionally fully removing one test
where the wrong mode was being tested.
Signed-off-by: Tom Daubney <Thomas.Daubney@arm.com>
Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
The mode parameter has been removed from the
mbedtls_rsa_pkcs1_decrypt function. The change
has been progagated to all function calls,
including in test suite .function files.
Signed-off-by: Thomas Daubney <thomas.daubney@arm.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>
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 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>
* 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>
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>
Since the loading attempt of a builtin key might be followed by trying
to load a persistent key, we can only wipe the allocated key data, not
the associated metadata.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
This reverts commit c75d9f589b.
This was merged by mistake in development instead of development_3.0.
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
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>
When creating a persistent key or registering a key
with an invalid key identifier return
PSA_ERROR_INVALID_ARGUMENT instead of
PSA_ERROR_INVALID_HANDLE.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Remove cipher_generate_iv driver entry point as there
is no known use case to delegate this to a driver.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Symmetric key management is not intended to be
delegated to drivers. Thus, key management code
for a given symmetric key type should be included
in the library whether or not the support for
cryptographic operations based on that type of
symmetric key may be delegated to drivers.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Move members that are of no use to the PSA crypto core
to the Mbed TLS implementation specific operation context.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
For cipher multi-part operations, dispatch based on
the driver identifier even in the case of the
Mbed TLS software implementation (viewed as a driver).
Also use the driver identifier to check that an
cipher operation context is active or not.
This aligns the way hash and cipher multi-part
operations are dispatched.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Change the operation context to the PSA one to be
able to call the software implementation from
the driver wrapper later on.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Change the signature of
psa_driver_wrapper_cipher_encrypt/decrypt_setup to
that of a PSA driver cipher_encrypt/decrypt_setup
entry point.
Change the operation context to the PSA one to be
able to call the software implementation from
the driver wrapper later on.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Split out the cipher setup based on cipher.c
in psa_cipher_setup_internal() whose signature
is that of a PSA driver cipher_setup entry
point.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Rework psa_cipher_setup in preparation of
calling the cipher setup based on cipher.c
through the interface of a PSA driver
cipher_setup entry point.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
To run succesfully the test
"PSA sign: invalid algorithm for ECC key" of
test_suite_psa_crypto when ECDSA support is not included
in the library, always return INVALID_ARGUMENT
in case of an ECC key not used for ECDSA, whether
ECDSA support is present or not.
Then apply the same logic to RSA sign RSA and RSA/ECC
verify for the sake of consistency.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Add missing PSA_WANT_CCM/GCM/CMAC. This completes
the set of PSA_WANT config options given the
current support of PSA crypto in Mbed TLS.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
If an elliptic curve was enabled in the Mbed TLS classic API (#define
MBEDTLS_ECP_DP_xxx), but not enabled in the PSA configuration (#define
PSA_WANT_ECC_xxx), it would still work if you tried to use it through
PSA.
This is generally benign, but could be a security issue if you want to
disable a curve in PSA for some security reason (such as a known bug
in its implementation, which may not matter in the classic API if Mbed
TLS is running in a secure enclave and is only reachable from
untrusted callers through the PSA API). More urgently, this broke
test_suite_psa_crypto_not_supported.generated.
So if a curve is not enabled in the PSA configuration, ensure that
it's treated as unsupported through the PSA software implementation.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
`entropy_poll.h` is not supposed to be used by application code and
is therefore being made internal.
Signed-off-by: Chris Jones <christopher.jones@arm.com>
Revert changes introduced in 50518f4195
as it is now clear that these headers are internal without the
`*_internal.h` suffix.
Signed-off-by: Chris Jones <christopher.jones@arm.com>
Simple find and replace using `#include (<|")mbedtls/(.*)_internal.h(>|")`
and `#include $1$2_internal.h$3`.
Also re-generated visualc files by running
`scripts/generate_visualc_files.pl`.
Signed-off-by: Chris Jones <christopher.jones@arm.com>
Apparently there's a goal to make the PSA Crypto core free from
dynamic memory allocations. Therefore, all driver context structures
need to be known at compile time in order for the core to know their
final size.
This change defines & implements for hashing operations how the context
structures get defined.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
mac size is previously checked to not be less than 4, so it can't be zero
anymore at this point.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
When ECDSA is not supported by the library, prefer
to return NOT_SUPPORTED than INVALID_ARGUMENT when
asked for an ECDSA signature.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Move the check that ECDSA is supported from the
caller of the function responsible for Mbed TLS
ECDSA signatures to this function, namely
mbedtls_psa_ecdsa_sign_hash().
This makes the caller code more readable and is
more aligned with what is expected from a
sign_hash() PSA driver entry point.
Add a negative test case where a deterministic
ECDSA signature is requested while the library
does not support deterministic ECDSA.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Reworked the validation of MAC algorithm with the used key type by
introducing psa_mac_key_can_do, which guarantees that PSA_MAC_LENGTH can
be called successfully after validation of the algorithm and key type.
This means psa_get_mac_output_length is no longer required.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Comparing algorithm with its FULL_LENGTH_MAC version doesn't work in
cases where algorithm is a wildcard. Wildcard input is not specified in
the documentation of the function, but in order to test the function
using the same test as PSA_MAC_LENGTH we're mimicking that behaviour here.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Avoid code duplication. Also update the guarantees made by the function
doc to match the guarantees given by PSA_MAC_LENGTH.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
This makes it more in-line with how psa_key_policy_permits works. It
also adds consistency: the intersection of MAC with default length and
MAC with exact-length is now computed correctly in case the exact length
equals the default length of the algorithm when used with the given
key type.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>
Change psa_ecdsa_sign/verify signature to that of
a sign/verify_hash driver entry point before to
move them to the psa_crypto_ecp.c ECP specific file.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Change psa_rsa_sign/verify signature to that of
a sign/verify_hash driver entry point before to
move them to the psa_crypto_rsa.c RSA specific file.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Change psa_driver_wrapper_sign/verify_hash signature
to that of a sign/verify_hash driver entry point.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Wrap sign/verify_hash software implementation into
psa_sign/verify_hash_internal() functions whose
signature is that of a sign/verify_hash driver
entry point.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Change the psa_crypto use of the CHACHA20 cipher to also use the new
MBEDTLS_PSA_BUILTIN_KE_TYPE_CHACHA20.
Signed-off-by: David Brown <david.brown@linaro.org>
Change a few conditionals in the psa library to be based on the
MBEDTLS_PSA_BUILTIN_KEY_TYPE_DES instead of the WANT macros. Future
additions of HW acceleration will need to be mindful of these
definitions if any of this code is needed in those instances.
Signed-off-by: David Brown <david.brown@linaro.org>
When converting definitions to use the new PSA defines, one erroneously
was conditionalized on the WANT macro instead of on the BUILTIN macro.
Signed-off-by: David Brown <david.brown@linaro.org>
There are a few instances of MBEDTLS_*_C (specifically for DES) in
psa_crypto.c. Change to the PSA_WANT_KEY_TYPE_DES macros to reflect the
new PSA crypto config.
Signed-off-by: David Brown <david.brown@linaro.org>
This file will always be used with the PSA configurations, so use the
MBEDTLS_PSA_BUILTIN... definitions for the symmetric cyphers.
Signed-off-by: David Brown <david.brown@linaro.org>
Use PSA_EXPORT_KEY_OUTPUT_SIZE macro to compute the
size of the buffer to contain the generated key
instead of computing it alongside the key type and
size validation.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
When generating transparent keys, we need to be able
to compute the size of the key buffer whether the
key is generated by the Mbed TLS library or by an
accelerator. Thus, change the RSA/ECP
MBEDTLS_PSA_BUILTIN_... compilation guards with
their PSA_WANT_... counterparts.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Change psa_generate_key_internal() signature to
that of a PSA driver generate_key entry point.
That way, this function can be called by the
driver wrapper when a software fallback is
necessary.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Preparatory commit to eventually change
psa_generate_key_internal() signature to that of
a PSA driver generate_key entry point.
To be able to change the signature, the buffer to
store the generated key has to be allocated before
the call to psa_generate_key_internal().
This commit moves the allocation and clean-up in
case of error of the buffer to store the generated
key from psa_generate_key_internal() to
psa_generate_key().
This has the nice benefit of factorizing the key
buffer allocation and clean-up.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Preparatory commit to eventually change
psa_generate_key_internal() signature to that of
a PSA driver generate_key entry point.
To be able to change the signature, the buffer to
store the key has to be allocated before the call
to psa_generate_key_internal() thus its size has
to be calculed beforehand as well.
This is the purpose of this commit: to move the
computation of the key size in bytes out of
psa_generate_key_internal().
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Small improvements to psa_generate_key_internal()
implementation:
. declare only once the status local variable and
initialize it to PSA_ERROR_CORRUPTION_DETECTED
to improve robustness against FI attacks.
. remove an unnecessary assignment.
. use type local variable instead of its global
variable equivalent.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
This brings them in line with PSA Crypto API 1.0.0
PSA_ALG_AEAD_WITH_DEFAULT_TAG_LENGTH -> PSA_ALG_AEAD_WITH_DEFAULT_LENGTH_TAG
PSA_ALG_AEAD_WITH_TAG_LENGTH -> PSA_ALG_AEAD_WITH_SHORTENED_TAG
Signed-off-by: Bence Szépkúti <bence.szepkuti@arm.com>
In psa_generate_derived_key_internal() an error case was returning
directly rather than jumping to the exit label, which meant that an
allocated buffer would not be free'd.
Found via coverity.
Signed-off-by: Paul Elliott <paul.elliott@arm.com>
Attempting to create an ECC key with a curve specification that is not
valid can plausibly fail with PSA_ERROR_INVALID_ARGUMENT ("this is not
a curve specification at all") or PSA_ERROR_NOT_SUPPORTED ("this may
be a curve specification, but not one I support"). The choice of error
is somewhat subjective.
Before this commit, due to happenstance in the implementation, an
attempt to use a curve that is declared in the PSA API but not
implemented in Mbed TLS returned PSA_ERROR_INVALID_ARGUMENT, whereas
an attempt to use a curve that Mbed TLS supports but for which support
was disabled at compile-time returned PSA_ERROR_NOT_SUPPORTED. This
inconsistency made it difficult to write negative tests that could
work whether the curve is implemented via Mbed TLS code or via a
driver.
After this commit, any attempt to use parameters that are not
recognized fails with NOT_SUPPORTED, whether a curve with the
specified size might plausibly exist or not, because "might plausibly
exist" is not something Mbed TLS can determine.
To keep returning INVALID_ARGUMENT when importing an ECC key with an
explicit "bits" attribute that is inconsistent with the size of the
key material, this commit changes the way mbedtls_ecc_group_of_psa()
works: it now works on a size in bits rather than bytes, with an extra
flag indicating whether the bit-size must be exact or not.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Move key buffer allocation from psa_import_key_into_slot()
function up to the two functions calling it.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Rename ECP key import function before to move
it to psa_crypto_ecp.c to adapt to the naming
of exported functions in psa_crypto_ecp.c.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Rename psa_import_rsa_key to mbedtls_psa_rsa_import_key to
align its name with the naming conventions of exported
functions in psa_crypto_rsa.c.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Change psa_export_(public_)key_internal signature to
the signature of an export_(public_)key driver entry
point.
This is a preparatory commit to be able to call the
software implementations as a driver.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Disentangle public export and export code to be
able to move the call to export and public
export operations to the driver wrapper.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Align naming of export internal functions with the way
other psa_crypto.c internal functions are named, ending
with _internal.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Rename psa_export_rsa/ecp_key to
mbedtls_psa_rsa/ecp_export_key before to move them to
RSA/ECP specific PSA crypto C files.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Rename psa_load_rsa/ecp_representation to
mbedtls_psa_rsa/ecp_load_representation
before to move them in their RSA/ECP
specific PSA crypto C modules.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Change psa_driver_wrapper_export_public_key() signature
to the signature of an export_public_key driver entry point.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
In the course of the development of the PSA unified
driver interface, the validate_key entry point for
opaque drivers has been removed and replaced by an
import_key entry point. This commit takes into account
this change of specification.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
In key slots containing the description of a key of a
dynamically registered Secure Element (SE), store the
key slot number in a key context as defined in the
PSA driver interface for opaque drivers.
That way transparent key data and slot numbers are
, in a key slot, both stored in a dynamically allocated
buffer. The `data` union in structures of type
psa_key_slot_t to distinguish between the storage of
transparent key data and slot numbers is consequently
not necessary anymore and thus removed.
This alignement of some part of the code dedicated to
dynamically registered SE with the PSA driver interface
specification is done to ease the support of both
dynamically registered and statically defined secure
elements.
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Rename the enum constants TLS12_PRF_xxx, which are declared in a
public header but not intended for use in application code, to start
with MBEDTLS_PSA_.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
When an Mbed TLS error code combines a low-level error and a
high-level error, the low-level error is usually closer to the root
cause (for example HW_ACCEL_FAILED or ENTROPY_SOURCE_FAILED is more
informative than RSA_PRIVATE_FAILED). So prioritize the low-level code
when converting to a PSA error code, rather than the high-level code
as was (rather arbitrarily) done before.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
Closing a wrapped key with the new SE driver interface while
MBEDTLS_PSA_CRYPTO_SE_C is also enabled leads to the key material not
being freed, even though an old SE driver is not in use, leading to a
memory leak. This is because a wrapped key is also considered external.
This commit extends the check for skipping by checking whether an
old-style SE driver is registered with the provided slot, in addition to
checking whether the key is external.
Signed-off-by: Fredrik Strupe <fredrik.strupe@silabs.com>
Make it clear that this is an abstraction of the random generator
abstraction, and not an abstraction of the PSA random generator.
mbedtls_psa_get_random and MBEDTLS_PSA_RANDOM_STATE are public-facing
definitions and will be moved in a subsequent commit.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
