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ssl – TLS/SSL wrapper for socket objects.

TLS/SSL wrapper for socket objects.

This module implements a subset of the corresponding CPython module, as described below. For more information, refer to the original CPython documentation: ssl.

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.

Attributes

`CERT_NONE`	Supported values for cert_reqs parameter, and the `SSLContext.verify_mode`
`CERT_OPTIONAL`	Supported values for cert_reqs parameter, and the `SSLContext.verify_mode`
`CERT_REQUIRED`	Supported values for cert_reqs parameter, and the `SSLContext.verify_mode`
`PROTOCOL_TLS_CLIENT`	Supported values for the protocol parameter.
`PROTOCOL_TLS_SERVER`	Supported values for the protocol parameter.
`SSLError`	This exception does NOT exist. Instead its base class, OSError, is used.

Classes

SSLContext

Create a new SSLContext instance. The protocol argument must be one of the PROTOCOL_*

Functions

wrap_socket(→ IO)

Wrap the given sock and return a new wrapped-socket object. The implementation

Module Contents

class ssl.SSLContext(protocol)

Create a new SSLContext instance. The protocol argument must be one of the PROTOCOL_* constants.

get_ciphers() → List[str]: Get a list of enabled ciphers, returned as a list of strings.

load_cert_chain(certfile, keyfile) → None: 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.

load_verify_locations(cafile=None, cadata=None) → 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.

set_ciphers(ciphers) → None: Set the available ciphers for sockets created with this context. ciphers should be a list of strings in the IANA cipher suite format .

wrap_socket(sock, *, server_side=False, do_handshake_on_connect=True, server_hostname=None) → Incomplete

Takes a stream sock (usually socket.socket instance of SOCK_STREAM type), and returns an instance of ssl.SSLSocket, wrapping the underlying stream. The returned object has the usual stream interface methods like read(), write(), etc.

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_socket or 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_socket is in non-blocking mode) the handshake should generally be deferred because otherwise wrap_socket blocks 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.

ssl.wrap_socket(sock, server_side=False, key=None, cert=None, cert_reqs=None, cadata=None, server_hostname=None, do_handshake=True) → IO

Wrap the given sock and return a new wrapped-socket object. The implementation of this function is to first create an SSLContext and then call the SSLContext.wrap_socket method 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_NONE and ssl.CERT_OPTIONAL will not validate any certificate, only ssl.CERT_REQUIRED will.
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.

ssl.CERT_NONE: Incomplete: Supported values for cert_reqs parameter, and the SSLContext.verify_mode attribute.

ssl.CERT_OPTIONAL: Incomplete: Supported values for cert_reqs parameter, and the SSLContext.verify_mode attribute.

ssl.CERT_REQUIRED: Incomplete: Supported values for cert_reqs parameter, and the SSLContext.verify_mode attribute.

ssl.PROTOCOL_TLS_CLIENT: Incomplete: Supported values for the protocol parameter.

ssl.PROTOCOL_TLS_SERVER: Incomplete: Supported values for the protocol parameter.

ssl.SSLError: Incomplete: This exception does NOT exist. Instead its base class, OSError, is used.