Fix missing SecurityLevel of the EndpointDescription

According to Part 4 - 7.10 this should be an a number that indicates how secure the EndPoint is. The number is Server implementation specific, how higher the number how saver.

asyncua/server/server.py

@@ -402,6 +402,63 @@ class Server:
                                              ua.MessageSecurityMode.Sign, self.certificate, self.iserver.private_key,
                                              permission_ruleset=self._permission_ruleset))
 
+
+    @staticmethod
+    def lookup_security_level_for_policy_type( security_policy_type: ua.SecurityPolicyType ) -> ua.Byte:
+        """Returns the security level for an ua.SecurityPolicyType.
+
+        This is endpoint & server implementation specific!
+
+        Returns:
+            ua.Byte: the found security level
+        """
+
+        return ua.Byte({
+            ua.SecurityPolicyType.NoSecurity : 0,
+            ua.SecurityPolicyType.Basic128Rsa15_Sign : 1,
+            ua.SecurityPolicyType.Basic128Rsa15_SignAndEncrypt : 2,
+            ua.SecurityPolicyType.Basic256_Sign : 11,
+            ua.SecurityPolicyType.Basic256_SignAndEncrypt : 21,
+            ua.SecurityPolicyType.Basic256Sha256_Sign : 50,
+            ua.SecurityPolicyType.Basic256Sha256_SignAndEncrypt : 70,
+            ua.SecurityPolicyType.Aes128Sha256RsaOaep_Sign : 55,
+            ua.SecurityPolicyType.Aes128Sha256RsaOaep_SignAndEncrypt : 75
+        }[security_policy_type])
+
+
+    @staticmethod
+    def determine_security_level(security_policy_uri:str, security_mode: ua.MessageSecurityMode) -> ua.Byte:
+        """Determine the security level of an EndPoint.
+        The security level indicates how secure an EndPoint is, compared to other EndPoints of the same server.
+        Value 0 is a special value; EndPoint isn't recommended, typical for ua.MessageSecurityMode.None_.
+
+        See Part 4 7.10
+
+        To the determine the level the value of ua.SecurityPolicyType is used.
+        The enum values already correspond to and
+        The Enum ua.SecurityPolicyType already contains a value per Enum entry that already correspond to
+
+
+        Args:
+            security_policy (ua.SecurityPolicy): the used policy
+            security_mode (ua.MessageSecurityMode): the used security mode for the messages.
+
+        Returns:
+            ua.Byte: the returned security level
+        """
+        security_level: ua.Byte = ua.Byte(0)
+
+        if security_mode != ua.MessageSecurityMode.None_:
+            security_policy_name = f'{security_policy_uri.split("#")[1].replace("_","")}_{security_mode.name}'
+
+            try:
+                security_policy_type: ua.SecurityPolicyType = ua.SecurityPolicyType[security_policy_name]
+                security_level = Server.lookup_security_level_for_policy_type(security_policy_type)
+            except KeyError:
+                _logger.error('"%s" isn\'t a valid security policy', security_policy_name)
+
+        return security_level
+
     def _set_endpoints(self, policy=ua.SecurityPolicy, mode=ua.MessageSecurityMode.None_):
         idtokens = []
         supported_token_classes = []
@@ -442,7 +499,7 @@ class Server:
         edp.SecurityPolicyUri = policy.URI
         edp.UserIdentityTokens = idtokens
         edp.TransportProfileUri = "http://opcfoundation.org/UA-Profile/Transport/uatcp-uasc-uabinary"
-        edp.SecurityLevel = 0
+        edp.SecurityLevel = Server.determine_security_level(policy.URI, mode)
         self.iserver.add_endpoint(edp)
         self.iserver.supported_tokens = tuple(supported_token_classes)
 

tests/test_crypto_connect.py

@@ -452,3 +452,27 @@ async def test_anonymous_rejection():
     with pytest.raises(ua.uaerrors.BadIdentityTokenRejected):
         await clt.connect()
     await srv.stop()
+
+async def test_security_level_all():
+    assert Server.determine_security_level(ua.SecurityPolicy.URI, ua.MessageSecurityMode.None_) == Server.lookup_security_level_for_policy_type(ua.SecurityPolicyType.NoSecurity)
+
+    assert Server.determine_security_level(security_policies.SecurityPolicyBasic256Sha256.URI, ua.MessageSecurityMode.Sign) == Server.lookup_security_level_for_policy_type(ua.SecurityPolicyType.Basic256Sha256_Sign)
+    assert Server.determine_security_level(security_policies.SecurityPolicyBasic256Sha256.URI, ua.MessageSecurityMode.SignAndEncrypt) == Server.lookup_security_level_for_policy_type(ua.SecurityPolicyType.Basic256Sha256_SignAndEncrypt)
+
+    assert Server.determine_security_level(security_policies.SecurityPolicyAes128Sha256RsaOaep.URI, ua.MessageSecurityMode.Sign) == Server.lookup_security_level_for_policy_type(ua.SecurityPolicyType.Aes128Sha256RsaOaep_Sign)
+    assert Server.determine_security_level(security_policies.SecurityPolicyAes128Sha256RsaOaep.URI, ua.MessageSecurityMode.SignAndEncrypt) == Server.lookup_security_level_for_policy_type(ua.SecurityPolicyType.Aes128Sha256RsaOaep_SignAndEncrypt)
+
+    # For the sake of completeness also the old, not recommended, protocols Basic128Rsa15 and Basic256
+    assert Server.determine_security_level(security_policies.SecurityPolicyBasic128Rsa15.URI, ua.MessageSecurityMode.Sign) == Server.lookup_security_level_for_policy_type(ua.SecurityPolicyType.Basic128Rsa15_Sign)
+    assert Server.determine_security_level(security_policies.SecurityPolicyBasic128Rsa15.URI, ua.MessageSecurityMode.SignAndEncrypt) == Server.lookup_security_level_for_policy_type(ua.SecurityPolicyType.Basic128Rsa15_SignAndEncrypt)
+
+    assert Server.determine_security_level(security_policies.SecurityPolicyBasic256.URI, ua.MessageSecurityMode.Sign) == Server.lookup_security_level_for_policy_type(ua.SecurityPolicyType.Basic256_Sign)
+    assert Server.determine_security_level(security_policies.SecurityPolicyBasic256.URI, ua.MessageSecurityMode.SignAndEncrypt) == Server.lookup_security_level_for_policy_type(ua.SecurityPolicyType.Basic256_SignAndEncrypt)
+
+async def test_security_level_endpoints(srv_crypto_all_certs):
+    srv = srv_crypto_all_certs[0]
+
+    end_points: list[ua.EndpointDescription] = await srv.get_endpoints()
+
+    for end_point in end_points:
+        assert end_point.SecurityLevel == Server.determine_security_level(end_point.SecurityPolicyUri, end_point.SecurityMode)