Code Access Security

Microsoft Dynamics AX 2009

Code Access Security (CAS) helps protect APIs that have potential security risks when the APIs are running on the server.

CAS-enabled APIs called on the server require the use of a permission class—one of the classes derived from CodeAccessPermission. If permission to use the API is not asserted, the following error is generated:

Request for the permission of type '%1' failed.

This error is also generated if permission is asserted, but the code is running on the client. Permission is required only for CAS-enabled APIs that run on the server. The string supplied in the error message is the name of one of the following permission classes:

ExecutePermission
FileIoPermission
InteropPermission
RunAsPermission
SkipAOSValidationPermission
SqlDataDictionaryPermission
SqlStatementExecutePermission
SysDatabaseLogPermission

For a list of CAS-enabled APIs, see Secured APIs.

You can CAS-enable your own APIs. For more information, see How to: Secure an API on the AOS.

Call a CAS-enabled API

Declare a variable for the relevant permission class.
Create a new instance of the class.
Request permission by using the assert method on the permission class.
Revert the assertion (to limit the scope of the permission) after the CAS-enabled API has been used; optional. Permission is automatically reverted when the method finishes executing.

Example

{
    DictClass dictClass;
    anytype   retVal;
    str       resultOutput;
    // Variable for the permission class.
    ExecutePermission perm;
    ;
    
    perm = new ExecutePermission();
 
    // Grants permission to execute the DictClass.callObject method.
    // DictClass.callObject is protected by code access security.
    perm.assert();
 
    dictClass = new DictClass(classidget(infolog));
    if (dictClass != null)
    {
        retVal       = dictClass.callObject("toString", infolog);
        resultOutput = strfmt("Return value of is %1", retVal);
        print resultOutput;
        pause;
    }
    
    // Closes the code access permission scope.
    CodeAccessPermission::revertAssert();
}