Is there any .NET API to get all the firewall rules

Question

We have an application which add some rules to firewall. We need to retrieve the rules of firewall so that we can check whether the rule exists in the firewall. I am using C#.

[Here](http://www.codeproject.com/Articles/19003/The-managed-classes-to-read-Windows-Firewall-confi) you can find an old article on reading the property settings of the Windows Vista Firewall. Don't know if it is still valid — Steve, Apr 26 '12 at 22:35

score 4 · Answer 1 · edited Oct 22 '18 at 16:11

Search the Firewall rules using a rule Name and remove it:

public static void RemoveFirewallRules(string RuleName)
{
    try
    {
        Type tNetFwPolicy2 = Type.GetTypeFromProgID("HNetCfg.FwPolicy2");
        INetFwPolicy2 fwPolicy2 = (INetFwPolicy2)Activator.CreateInstance(tNetFwPolicy2);
        var currentProfiles = fwPolicy2.CurrentProfileTypes;               

        // List of rules
        // List<INetFwRule> RuleList = new List<INetFwRule>();

        foreach (INetFwRule rule in fwPolicy2.Rules)
        {
            // Add a rule to list
            // RuleList.Add(rule);
            // Console.WriteLine(rule.Name);
            if (rule.Name.IndexOf(RuleName) != -1)
            {
                // Remove a rule
                INetFwPolicy2 firewallPolicy = (INetFwPolicy2)Activator.CreateInstance(Type.GetTypeFromProgID("HNetCfg.FwPolicy2"));                     
                firewallPolicy.Rules.Remove(rule.Name);
                Console.WriteLine(rule.Name + " has been deleted from the Firewall Policy");
            }
        }
    }
    catch (Exception r)
    {
        Console.WriteLine("Error deleting a Firewall rule");
    }
}

score 2 · Answer 2 · answered Dec 03 '18 at 20:50

If you dont want to add extra references to assemblies providing the INetFwPolicy2 interface, you can use the dynamic class in C# to reflect the "HNetCfg.FwPolicy2" type. See this working code:

Type tNetFwPolicy2 = Type.GetTypeFromProgID("HNetCfg.FwPolicy2");
dynamic fwPolicy2 = Activator.CreateInstance(tNetFwPolicy2) as dynamic;                          
IEnumerable Rules = fwPolicy2.Rules as IEnumerable;
foreach (dynamic rule in Rules)
  {
  if (rule.Name=="My firewall rule")
    {

    }                              
  }

Note that using the dynamic object in this way requires a reference to Microsoft.CSharp assembly.

score 0 · Answer 3 · answered Jan 28 '14 at 08:55

0

You can get an idea from this code.

INetFwPolicy2 fwPolicy2 = (INetFwPolicy2)Activator.CreateInstance(typeFWPolicy2);

List<INetFwRule> RuleList = new List<INetFwRule>();

foreach (INetFwRule rule in fwPolicy2.Rules)
{
  RuleList.Add(rule);
}

answered Jan 28 '14 at 08:55

Achira

1
2

2

There is more professional way to get list: fwPolicy2.Rules.Cast().ToList() – Vincent Jun 26 '19 at 15:48

IFink · Answer 4 · 2014-12-18T12:29:07.397

0

EDITED: INetFwPolicy2 is a .Net interface to manage Firewall rules msdn INetFwPolicy2 has a rules collection contains all ruls of this policy. You can query the Rules collection with Lambda, as follow:

INetFwPolicy2 fwPolicy = (INetFwPolicy2)Activator.CreateInstance(Type.GetTypeFromProgID("HNetCfg.FwPolicy2"));
fwPolicy2.Rules.OfType<INetFwRule>.Select....

and all other Lambda extensions.

edited Dec 18 '14 at 12:29

answered Dec 15 '14 at 13:22

IFink

724
16
28

You should really improve this answer by showing the type of fwPolicy2, preferably the fully qualified name, and preferably with a link to its documentation. – nos Dec 15 '14 at 13:27

Is there any .NET API to get all the firewall rules

4 Answers4

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