Previously, PSA used SubjectPublicKeyInfo structures to serialize EC public keys.
This has recently been changed to using ECPoint structures instead, but the wrapper
making PSA ECDSA verification available through Mbed TLS' PK API hasn't yet been
adapted accordingly - which is what this commit does.
Luckily, Mbed TLS' PK API offers two functions mbedtls_pk_write_pubkey()
and mbedtls_pk_write_pubkey_der(), the latter exporting a SubjectPublicKeyInfo
structure and the former exporting an ECPoint structure in case of EC public
keys. For the adaptation of the ECDSA wrapper ecdsa_verify_wrap() it is therefore
sufficient to use mbedtls_pk_write_pubkey() instead of mbedtls_pk_write_pubkey_der().
Remove extra status handling code from psa_import_key_into_slot(). This
helps save a tiny amount of code space, but mainly serves to improve the
readability of the code.
Move pk-using code to inside psa_import_rsa_key(). This aligns the shape
of psa_import_rsa_key() to match that of psa_import_ec_private_key() and
psa_import_ec_public_key().
Remove front matter from our EC key format, to make it just the contents
of an ECPoint as defined by SEC1 section 2.3.3.
As a consequence of the simplification, remove the restriction on not
being able to use an ECDH key with ECDSA. There is no longer any OID
specified when importing a key, so we can't reject importing of an ECDH
key for the purpose of ECDSA based on the OID.
Use the PSA-native status type in psa_key_agreement_ecdh() in
preparation for us calling PSA functions (and not just Mbed TLS
functions) and still being able to return a psa_status_t (without having
to translate it to a Mbed TLS error and then back again).
Remove pkcs-1 and rsaEncryption front matter from RSA public keys. Move
code that was shared between RSA and other key types (like EC keys) to
be used only with non-RSA keys.
Remove the type and bits arguments to psa_allocate_key() and
psa_create_key(). They can be useful if the implementation wants to
know exactly how much space to allocate for the slot, but many
implementations (including ours) don't care, and it's possible to work
around their lack by deferring size-dependent actions to the time when
the key material is created. They are a burden to applications and
make the API more complex, and the benefits aren't worth it.
Change the API and adapt the implementation, the units test and the
sample code accordingly.
When MBEDTLS_PSA_CRYPTO_SPM is defined, the code is being built for SPM (Secure Partition Manager)
integration which separates the code into two parts: NSPE (Non-Secure Processing Environment) and SPE
(Secure Processing Environment). When building for the SPE, an additional header file should be included.
You can use PSA_ALG_ANY_HASH to build the algorithm value for a
hash-and-sign algorithm in a policy. Then the policy allows usage with
this hash-and-sign family with any hash.
Test that PSA_ALG_ANY_HASH-based policies allow a specific hash, but
not a different hash-and-sign family. Test that PSA_ALG_ANY_HASH is
not valid for operations, only in policies.
Test for a subclass of public-key algorithm: those that perform
full-domain hashing, i.e. algorithms that can be broken down as
sign(key, hash(message)).
Copy the nice and clear documentation from psa_export_key() as to what
implementations are allowed to do regarding key export formats, as the
same applies to public keys.
Previously we weren't initializing the freshly allocated ECP keypair
when importing private EC keys. This didn't seem to cause problems, at
least according to our current test coverage, but it's better to ensure
we don't have a partially initialized object by explicitly initializing
the keypair.
