Allow supplying regulatory domain at runtime

README.md

@@ -221,6 +221,8 @@ The `:wifi` key has the following common fields:
   * 1:  Do passive scans.
 * `:priority`: The priority to set for a network if you are using multiple network
  configurations
+* `:regulatory_domain`: Two character country code. Technology configuration
+ will take priority over Application configuration
 * `:networks` - A list of WiFi networks to configure, these configs have the same
  fields listed above
 
@@ -301,6 +303,21 @@ iex> VintageNet.configure("wlan0", %{
 })
 ```
 
+Example of setting regulatory domain:
+
+```elixir
+iex> VintageNet.configure("wlan0", %{
+      type: VintageNet.Technology.WiFi,
+      wifi: %{
+        ssid: "testing",
+        key_mgmt: :wpa_psk,
+        psk: "super secret",
+        regulatory_domain: "US"
+      },
+      ipv4: %{method: :dhcp}
+})
+```
+
 ### LTE
 
 TBD

lib/vintage_net/technology/wifi.ex

@@ -175,7 +175,7 @@ defmodule VintageNet.Technology.WiFi do
   defp wifi_to_supplicant_contents(wifi, control_interface_dir, regulatory_domain) do
     config = [
       "ctrl_interface=#{control_interface_dir}",
-      "country=#{regulatory_domain}",
+      "country=#{wifi[:regulatory_domain] || regulatory_domain}",
       into_config_string(wifi, :bgscan),
       into_config_string(wifi, :ap_scan)
     ]

test/vintage_net/technology/wifi_test.exs

@@ -85,6 +85,54 @@ defmodule VintageNet.Technology.WiFiTest do
     assert {:ok, output} == WiFi.to_raw_config("wlan0", input, default_opts())
   end
 
+  test "Set regulatory_domain at runtime" do
+    input = %{
+      type: VintageNet.Technology.WiFi,
+      wifi: %{
+        regulatory_domain: "AU"
+      },
+      ipv4: %{method: :dhcp},
+      hostname: "unit_test"
+    }
+
+    output = %RawConfig{
+      ifname: "wlan0",
+      type: VintageNet.Technology.WiFi,
+      source_config: normalize_config(input),
+      child_specs: [
+        {VintageNet.Interface.ConnectivityChecker, "wlan0"},
+        {VintageNet.WiFi.WPASupplicant,
+         [ifname: "wlan0", control_path: "/tmp/vintage_net/wpa_supplicant", ap_mode: false]}
+      ],
+      files: [
+        {"/tmp/vintage_net/network_interfaces.wlan0", dhcp_interface("wlan0", "unit_test")},
+        {"/tmp/vintage_net/wpa_supplicant.conf.wlan0",
+         """
+         ctrl_interface=/tmp/vintage_net/wpa_supplicant
+         country=AU
+         network={
+         }
+         """}
+      ],
+      up_cmd_millis: 60_000,
+      up_cmds: [
+        {:run_ignore_errors, "ifdown",
+         ["-i", "/tmp/vintage_net/network_interfaces.wlan0", "wlan0"]},
+        {:run_ignore_errors, "killall", ["-q", "wpa_supplicant"]},
+        {:run, "wpa_supplicant",
+         ["-B", "-i", "wlan0", "-c", "/tmp/vintage_net/wpa_supplicant.conf.wlan0", "-dd"]},
+        {:run, "ifup", ["-i", "/tmp/vintage_net/network_interfaces.wlan0", "wlan0"]}
+      ],
+      down_cmds: [
+        {:run, "ifdown", ["-i", "/tmp/vintage_net/network_interfaces.wlan0", "wlan0"]},
+        {:run, "killall", ["-q", "wpa_supplicant"]}
+      ],
+      cleanup_files: ["/tmp/vintage_net/wpa_supplicant/wlan0"]
+    }
+
+    assert {:ok, output} == WiFi.to_raw_config("wlan0", input, default_opts())
+  end
+
   test "create a WPA2 WiFi configuration with passphrase" do
     input = %{
       type: VintageNet.Technology.WiFi,