And only enable this method when the relevant feature is available in
mbedtls. Otherwise, if mbedtls doesn't support getting the peer
certificate, this method always returns None and it's confusing why it does
that. It's better to remove the method altogether, so the error trying to
use it is more obvious.
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>
Damien George