This matches the behaviour of run-tests.py, which sets cwd to the directory
containing the test script, which helps to isolate the filesystem.
It means that the SSL tests no longer need to know the name of their
containing directory to find the certificate files, and helps to run these
tests on bare-metal.
Signed-off-by: Damien George <damien@micropython.org>
This commit adds:
1) Methods to SSLContext class that match CPython signature:
- `SSLContext.load_cert_chain(certfile, keyfile)`
- `SSLContext.load_verify_locations(cafile=, cadata=)`
- `SSLContext.get_ciphers()` --> ["CIPHERSUITE"]
- `SSLContext.set_ciphers(["CIPHERSUITE"])`
2) `sslsocket.cipher()` to get current ciphersuite and protocol
version.
3) `ssl.MBEDTLS_VERSION` string constant.
4) Certificate verification errors info instead of
`MBEDTLS_ERR_X509_CERT_VERIFY_FAILED`.
5) Tests in `net_inet` and `multi_net` to test these new methods.
`SSLContext.load_cert_chain` method allows loading key and cert from disk
passing a filepath in `certfile` or `keyfile` options.
`SSLContext.load_verify_locations`'s `cafile` option enables the same
functionality for ca files.
Signed-off-by: Carlos Gil <carlosgilglez@gmail.com>