python-stdlib/ssl: Add ecdsa_sign_callback callback attribute.

This callback gets invoked to perform ECDSA signing if enabled.
See micropython/micropython#15905

Signed-off-by: iabdalkader <[email protected]>

Author: iabdalkader

python-stdlib/ssl/ssl.py

@@ -6,6 +6,7 @@ class SSLContext:
     def __init__(self, *args):
         self._context = tls.SSLContext(*args)
         self._context.verify_mode = CERT_NONE
+        self._context.ecdsa_sign_callback = None
 
     @property
     def verify_mode(self):
@@ -15,6 +16,14 @@ def verify_mode(self):
     def verify_mode(self, val):
         self._context.verify_mode = val
 
+    @property
+    def ecdsa_sign_callback(self):
+        return self._context.ecdsa_sign_callback
+
+    @ecdsa_sign_callback.setter
+    def ecdsa_sign_callback(self, val):
+        self._context.ecdsa_sign_callback = val
+
     def load_cert_chain(self, certfile, keyfile):
         if isinstance(certfile, str):
             with open(certfile, "rb") as f: