Adding an ICMP Rule

This example adds an ICMP rule using the Windows Firewall with Advanced Security APIs.

/********************************************************************++
Copyright (C) Microsoft. All Rights Reserved.

Abstract:
    This C++ file includes sample code that adds a ICMP rule 
    for the Private profile using the Microsoft Windows
    Firewall APIs.

--********************************************************************/

#include <windows.h>
#include <stdio.h>
#include <netfw.h>

#pragma comment( lib, "ole32.lib" )
#pragma comment( lib, "oleaut32.lib" )


// Forward declarations
HRESULT     WFCOMInitialize(INetFwPolicy2** ppNetFwPolicy2);


int __cdecl main()
{
    HRESULT hrComInit = S_OK;
    HRESULT hr = S_OK;

    INetFwPolicy2 *pNetFwPolicy2 = NULL;
    INetFwRules *pFwRules = NULL;
    INetFwRule *pFwRule = NULL;

    BSTR bstrRuleName = SysAllocString(L"ICMP_RULE");
    BSTR bstrRuleDescription = SysAllocString(L"Allow ICMP network traffic");
    BSTR bstrRuleGroup = SysAllocString(L"Sample Rule Group");
    // ICMP Echo Request
    BSTR bstrICMPTypeCode = SysAllocString(L"8:*");

    // Initialize COM.
    hrComInit = CoInitializeEx(
                    0,
                    COINIT_APARTMENTTHREADED
                    );

    // Ignore RPC_E_CHANGED_MODE; this just means that COM has already been
    // initialized with a different mode. Since we don't care what the mode is,
    // we'll just use the existing mode.
    if (hrComInit != RPC_E_CHANGED_MODE)
    {
        if (FAILED(hrComInit))
        {
            printf("CoInitializeEx failed: 0x%08lx\n", hrComInit);
            goto Cleanup;
        }
    }

    // Retrieve INetFwPolicy2
    hr = WFCOMInitialize(&amp;pNetFwPolicy2);
    if (FAILED(hr))
    {
        goto Cleanup;
    }

    // Retrieve INetFwRules
    hr = pNetFwPolicy2->get_Rules(&amp;pFwRules);
    if (FAILED(hr))
    {
        printf("get_Rules failed: 0x%08lx\n", hr);
        goto Cleanup;
    }

    // Create a new Firewall Rule object.
    hr = CoCreateInstance(
                __uuidof(NetFwRule),
                NULL,
                CLSCTX_INPROC_SERVER,
                __uuidof(INetFwRule),
                (void**)&amp;pFwRule);
    if (FAILED(hr))
    {
        printf("CoCreateInstance for Firewall Rule failed: 0x%08lx\n", hr);
        goto Cleanup;
    }

    // Populate the Firewall Rule object
    pFwRule->put_Name(bstrRuleName);
    pFwRule->put_Description(bstrRuleDescription);
    pFwRule->put_Protocol(1);
    pFwRule->put_IcmpTypesAndCodes(bstrICMPTypeCode);
    pFwRule->put_Grouping(bstrRuleGroup);
    pFwRule->put_Profiles(NET_FW_PROFILE2_PRIVATE);
    pFwRule->put_Action(NET_FW_ACTION_ALLOW);
    pFwRule->put_Enabled(VARIANT_TRUE);

    // Add the Firewall Rule
    hr = pFwRules->Add(pFwRule);
    if (FAILED(hr))
    {
        printf("Firewall Rule Add failed: 0x%08lx\n", hr);
        goto Cleanup;
    }

Cleanup:

    // Free BSTR's
    SysFreeString(bstrRuleName);
    SysFreeString(bstrRuleDescription);
    SysFreeString(bstrRuleGroup);
    SysFreeString(bstrICMPTypeCode);

    // Release the INetFwRule object
    if (pFwRule != NULL)
    {
        pFwRule->Release();
    }

    // Release the INetFwRules object
    if (pFwRules != NULL)
    {
        pFwRules->Release();
    }

    // Release the INetFwPolicy2 object
    if (pNetFwPolicy2 != NULL)
    {
        pNetFwPolicy2->Release();
    }

    // Uninitialize COM.
    if (SUCCEEDED(hrComInit))
    {
        CoUninitialize();
    }
   
    return 0;
}


// Instantiate INetFwPolicy2
HRESULT WFCOMInitialize(INetFwPolicy2** ppNetFwPolicy2)
{
    HRESULT hr = S_OK;

    hr = CoCreateInstance(
        __uuidof(NetFwPolicy2), 
        NULL, 
        CLSCTX_INPROC_SERVER, 
        __uuidof(INetFwPolicy2), 
        (void**)ppNetFwPolicy2);

    if (FAILED(hr))
    {
        printf("CoCreateInstance for INetFwPolicy2 failed: 0x%08lx\n", hr);
        goto Cleanup;        
    }

Cleanup:
    return hr;
}