Few days ago, I began work on a Windows Firewall component in Delphi, and my work is currently up on Github.

The name of the unit containing the Windows Firewall component is called System.Win.Firewall, and the component is called TWindowsFirewall. The example project has 2 functions. 1 function lists all the firewall rules, and the other creates a rule, blocking a list of addresses.

The function that lists all the firewall rules, look like so:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
procedure ShowRule(const ARule: TWindowsFirewall.TWindowsFirewallRule);
begin
  WriteLn('Name: ', ARule.Name);
  WriteLn('Action: ', ARule.Action.ToString);
  WriteLn('Description: ', ARule.Description);
  WriteLn('Direction: ', ARule.Direction.ToString);
  WriteLn('Enabled: ', ARule.Enabled);
  WriteLn('Profile: ', ARule.Profile.ToString);
  WriteLn('Interface Types: ', ARule.InterfaceTypes.ToString);
  WriteLn('-----------------------------------');
end;
 
procedure EnumRules;
var
  LFirewall: TWindowsFirewall;
  LRule: TWindowsFirewall.TWindowsFirewallRule;
  LRuleName, LInterface: string;
begin
  LFirewall := TWindowsFirewall.Create;
  try
    for LRuleName in TArray<string>.Create('Doesn''t exist', 'Test rule using TWindowsFirewall') do
      if LFirewall.Rules.FindRule(LRuleName) then
        begin
          LRule := LFirewall.Rules[LRuleName];
          ShowRule(LRule);
          LRule.Free;
        end;
 
    for LRule in LFirewall.Rules do
      ShowRule(LRule);
 
  finally
    LFirewall.Free;
  end;
end;
 
begin
  EnumRules;
end.

Feel free to check out the repository, or if you're interested in extending/enhancing the component further,  or collaborate with me.