Reorganized the DH APIs into groups.
Reworked all DH APIs.
Improved testing of DH API.
Implemented wolfSSL_PEM_read_RSAPublicKey() and
wolfSSL_PEM_write_RSA_PUBKEY().
Fix public key PEM write implementations to use the correct
header/footer names.
Added support for "RSA PUBLIC KEY" in header and footer in DerToPemEx().
Reworked PEM read/write APIs to be independent. No longer create an EVP
to use common function - common functionality refectored out.
Similarly file APIs don't create a BIO and call the partner APIs.
Improved testing of PEM read/write APIs.
Generic read BIO from memory BIO now returns the buffer instead of
allocating memory and reading.
No longer reading chunks when a file BIO.
Added wolfssl_make_rng() to create or get get global random. All RSA and
DH APIs now use this. DH_generate_parameters() creates a random object
and use global on error rather than just using global random.
Changed implementations to use BIO_new_fp() instead of create a new BIO
and setting file pointer.
* Fix api.c build error with `NO_FILESYSTEM` and `WOLFSSL_CERT_EXT`.
* Fix for building tests/suites.c with static memory (missing `LARGEST_MEM_BUCKET`).
* Always expose `wc_ecc_set_rng` for compatibility.
This new function, wolfSSL_CTX_load_system_CA_certs, currently only supports
Linux-based OS's. It searches through conventional CA directories and once it
finds one, attempts to load CA certs from it. After the first directory is
found, we don't check the others.
This commit also adds a function wolfSSL_get_system_CA_dirs, which returns a
pointer to an array of directories where wolfSSL_CTX_load_system_CA_certs will
look for CA certs. This is used in a unit test, where we only want to expect
success if one of these directories actually exists on the test system.
Finally, this commit adds support for SSL_CTX_set_default_verify_paths to the
compatibility layer. It doesn't model the exact behavior of its OpenSSL
counterpart; it's mostly a wrapper around wolfSSL_CTX_load_system_CA_certs,
manipulating the return value of that function to conform to OpenSSL's
conventions.
