Revived from a previous PR by Gilles, see:
https://github.com/ARMmbed/mbedtls/pull/1293/files#diff-568ef321d275f2035b8b26a70ee9af0bR71
This will be useful in eliminating temporary stack buffers for transcoding the
signature: in order to do that in place we need to be able to make assumptions
about the size of the output buffer, which this macro will provide. (See next
commit.)
It's better for names in the API to describe the "what" (opaque keys) rather
than the "how" (using PSA), at least since we don't intend to have multiple
function doing the same "what" in different ways in the foreseeable future.
Unfortunately the can_do wrapper does not receive the key context as an
argument, so it cannot check psa_get_key_information(). Later we might want to
change our internal structures to fix this, but for now we'll just restrict
opaque PSA keys to be ECDSA keypairs, as this is the only thing we need for
now. It also simplifies testing a bit (no need to test each key type).
While at it, clarify who's responsible for destroying the underlying key. That
can't be us because some keys cannot be destroyed and we wouldn't know. So
let's leave that up to the caller.
In case of AEAD ciphers, the cipher mode (and not even the entire content
of mbedtls_cipher_info_t) doesn't uniquely determine a psa_algorithm_t
because it doesn't specify the AEAD tag length, which however is included
in psa_algorithm_t identifiers.
This commit adds a tag length value to mbedtls_psa_translate_cipher_mode()
to account for that ambiguity.
This commit adds the header file mbedtls/psa_util.h which contains
static utility functions `mbedtls_psa_xxx()` used in the integration
of PSA Crypto into Mbed TLS.
Warning: These functions are internal only and may change at any time.
Add a test to ensure that when the crypto submodule is not used, the crypto
library is not created and that libmbedcrypto.a does not contain symbols
from files contained within the crypto submodule.
- Check that libmbedcrypto was not built at the top level.
- Check that we've built libmbedcrypto with the correct files. Build
libmbedcrypto with debug symbols and verify that files used are from the
crypto submodule.
- Check that config.h is handled properly. Enable a feature at the top
level that the crypto library submodule has disabled in its config.h, and
check that the library symboles indicate that the feature is present in
libmbedcrypto.
- Ensure basic functionality of the resulting build with a run of
`make test` and `ssl-opt.sh`.
Without a "--detach" option, git worktree will refuse to checkout a branch
that's already checked out. This makes the abi_check.py script not very
useful for checking the currently checked out branch, as git will error
that the branch is already checked out. Add the "--detach" option to check
out the new temporary worktree in detached head mode. This is acceptable
because we aren't planning on working on the branch and just want a
checkout to do ABI checking from.
