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)¶
streamsock (usually socket.socket instance of
SOCK_STREAMtype), and returns an instance of ssl.SSLSocket, which wraps the underlying stream in an SSL context. Returned object has the usual
streaminterface methods like
write(), etc. A server-side SSL socket should be created from a normal socket returned from
accept()on a non-SSL listening server socket.
do_handshake 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 (there is no
do_handshakemethod as in CPython). 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.
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.
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.
Depending on the underlying module implementation in a particular MicroPython port, some or all keyword arguments above may be not supported.
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.
This exception does NOT exist. Instead its base class, OSError, is used.