With the removal of the MD handle from the MD context, it's a precondition
for any MD API outside of mbedtls_md_init() and mbedtls_md_setup() that
the MD context has been successfully setup by precisely those functions
beforehand, and hence must be bound to the single enabled valid MD handle.
As has been previously done for ciphersuites, this commit introduces
a zero-cost abstraction layer around the type
mbedtls_md_info const *
whose valid values represent implementations of message digest algorithms.
Access to a particular digest implementation can be requested by name or
digest ID through the API mbedtls_md_info_from_xxx(), which either returns
a valid implementation or NULL, representing failure.
This commit replaces such uses of `mbedtls_md_info const *` by an abstract
type `mbedtls_md_handle_t` whose valid values represent digest implementations,
and which has a designated invalid value MBEDTLS_MD_INVALID_HANDLE.
The purpose of this abstraction layer is to pave the way for builds which
support precisely one digest algorithm. In this case, mbedtls_md_handle_t
can be implemented as a two-valued type, with one value representing the
invalid handle, and the unique valid value representing the unique enabled
digest.
- Separate string and hex parameter as unhexify is moved out of the function. It's input should only be hex.
- Fix test mbedtls_ccm_encrypt_and_tag that grows input message buffer with tag
- Add missing expected length parameter in ECP TLS tests
- Add deleted TEST_ASSERT and mbedtls calls that got removed in script based code generation
Note from future self: actually md_init_ctx will be re-introduced with the
same signature later, and a new function with the additional argument will be
added.
Changes include:
- Integers marked with '#' in the .function files.
- Strings should have "" in .data files.
- String comparison instead of preprocessor-like replace for e.g. '=='
- Params and variables cannot have the same name in .function files
