Child was almost redundant as it's already saved in ver_chain, except it was
multiplexed to also indicate whether an operation is in progress. This commit
removes it and introduces an explicit state variable instead.
This state can be useful later if we start returning IN_PROGRESS at other
points than find_parent() (for example when checking CRL).
Note that the state goes none -> find_parent and stays there until the context
is free(), as it's only on the first call that nothing was in progress.
The fact that you needed to pass a pointer to mbedtls_ecdsa_restart_ctx (or
that you needed to know the key type of the PK context) was a breach of
abstraction.
Change the API (and callers) now, and the implementation will be changed in
the next commit.
The fact that self-signed end-entity certs can be explicitly trusted by
putting them in the CA list even if they don't have the CA bit was not
documented though it's intentional, and tested by "Certificate verification #73
(selfsigned trusted without CA bit)" in test_suite_x509parse.data
It is unclear to me whether the restriction that explicitly trusted end-entity
certs must be self-signed is a good one. However, it seems intentional as it is
tested in tests #42 and #43, so I'm not touching it for now.
Allow the size of the entry_name character array in x509_crt.c to be
configurable through a macro in config.h. entry_name holds a
path/filename string. The macro introduced in
MBEDTLS_X509_MAX_FILE_PATH_LEN.
- allows to express 'none' or 'all' more easily than lists
- more compact and easier to declare statically
- easier to check too
Only drawback: if we ever have more than 32 curves, we'll need an ABI change to
make that field a uint64_t.
