This module provides access to Transport Layer Security (previously and widely known as “Secure Sockets Layer”) encryption and peer authentication facilities for network sockets, both client-side and server-side.
- ssl.wrap_socket(sock, server_side=False, keyfile=None, certfile=None, cert_reqs=CERT_NONE, cadata=None, server_hostname=None, do_handshake=True)¶
Wrap the given sock and return a new wrapped-socket object. The implementation of this function is to first create an
SSLContextand then call the
SSLContext.wrap_socketmethod on that context object. The arguments sock, server_side and server_hostname are passed through unchanged to the method call. The argument do_handshake is passed through as do_handshake_on_connect. The remaining arguments have the following behaviour:
cert_reqs determines whether the peer (server or client) must present a valid certificate. Note that for mbedtls based ports,
ssl.CERT_OPTIONALwill not validate any certificate, only
cadata is a bytes object containing the CA certificate chain (in DER format) that will validate the peer’s certificate. Currently only a single DER-encoded certificate is supported.
Depending on the underlying module implementation in a particular MicroPython port, some or all keyword arguments above may be not supported.
- class ssl.SSLContext(protocol, /)¶
Create a new SSLContext instance. The protocol argument must be one of the
- SSLContext.load_cert_chain(certfile, keyfile)¶
Load a private key and the corresponding certificate. The certfile is a string with the file path of the certificate. The keyfile is a string with the file path of the private key.
Difference to CPython
MicroPython extension: certfile and keyfile can be bytes objects instead of strings, in which case they are interpreted as the actual certificate/key data.
- SSLContext.load_verify_locations(cafile=None, cadata=None)¶
Load the CA certificate chain that will validate the peer’s certificate. cafile is the file path of the CA certificates. cadata is a bytes object containing the CA certificates. Only one of these arguments should be provided.
Get a list of enabled ciphers, returned as a list of strings.
Set the available ciphers for sockets created with this context. ciphers should be a list of strings in the IANA cipher suite format .
- SSLContext.wrap_socket(sock, *, server_side=False, do_handshake_on_connect=True, server_hostname=None)¶
Takes a stream sock (usually socket.socket instance of
SOCK_STREAMtype), and returns an instance of ssl.SSLSocket, wrapping the underlying stream. The returned object has the usual stream interface methods like
server_side selects whether the wrapped socket is on the server or client side. A server-side SSL socket should be created from a normal socket returned from
accept()on a non-SSL listening server socket.
do_handshake_on_connect determines whether the handshake is done as part of the
wrap_socketor whether it is deferred to be done as part of the initial reads or writes For blocking sockets doing the handshake immediately is standard. For non-blocking sockets (i.e. when the sock passed into
wrap_socketis in non-blocking mode) the handshake should generally be deferred because otherwise
wrap_socketblocks until it completes. Note that in AXTLS the handshake can be deferred until the first read or write but it then blocks until completion.
server_hostname is for use as a client, and sets the hostname to check against the received server certificate. It also sets the name for Server Name Indication (SNI), allowing the server to present the proper certificate.
Some implementations of
ssl module do NOT validate server certificates,
which makes an SSL connection established prone to man-in-the-middle attacks.
wrap_socket returns an
SSLSocket object which has methods typical
for sockets, such as
recv, etc. MicroPython’s
returns an object more similar to CPython’s
SSLObject which does not have
these socket methods.
Set or get the behaviour for verification of peer certificates. Must be one of the
ssl.CERT_REQUIRED requires the device’s date/time to be properly set, e.g. using
mpremote rtc --set or
must be specified when on the client side.
This exception does NOT exist. Instead its base class, OSError, is used.