CA2145: Transparent methods should not be decorated with the SuppressUnmanagedCodeSecurityAttribute


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The latest version of this topic can be found at CA2145: Transparent methods should not be decorated with the SuppressUnmanagedCodeSecurityAttribute.

|Breaking Change|Breaking|

A transparent method, a method that is marked with the SecuritySafeCriticalAttribute method, or a type that contains a method is marked with the SuppressUnmanagedCodeSecurityAttribute attribute.

Methods decorated with the SuppressUnmanagedCodeSecurityAttribute attribute have an implicit LinkDemand placed upon any method that calls it. This LinkDemand requires that the calling code be security critical. Marking the method that uses SuppressUnmanagedCodeSecurity with the SecurityCriticalAttribute attribute makes this requirement more obvious for callers of the method.

To fix a violation of this rule, mark the method or type with the SecurityCriticalAttribute attribute.

Do not suppress a warning from this rule.


using System;
using System.Runtime.InteropServices;
using System.Security;

namespace TransparencyWarningsDemo

    public class SafeNativeMethods
        // CA2145 violation - transparent method marked SuppressUnmanagedCodeSecurity.  This should be fixed by
        // marking this method SecurityCritical.
        [DllImport("kernel32.dll", SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        internal static extern bool Beep(uint dwFreq, uint dwDuration);