Package to setup system wide HTTP(S) Proxy on Desktop Platforms

x/sysproxy/doc.go

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+// Copyright 2024 Jigsaw Operations LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/*
+Package sysproxy provides a simple interface to set/unset system-wide proxy settings.
+
+# Platform Support
+
+Currently this package supports desktop platforms only. The following platforms are supported:
+  - macOS
+  - Linux (Gnome)
+  - Windows
+
+# Usage
+
+To set up system-wide proxy settings, use the [SetProxy] function. This function takes two arguments: the IP address and the port of the proxy server.
+
+To unset system-wide proxy settings, use the [UnsetProxy] function.
+To ensure that the system-wide proxy settings are unset upon program termination, it is recommended to call:
+
+	defer UnsetProxy()
+
+when the application starts.
+*/
+package sysproxy

x/sysproxy/sysproxy_darwin.go

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+// Copyright 2024 Jigsaw Operations LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build darwin
+
+package sysproxy
+
+import (
+	"bytes"
+	"fmt"
+	"os/exec"
+	"strings"
+)
+
+type ProxyType string
+
+const (
+	httpProxyType  ProxyType = "web"
+	httpsProxyType ProxyType = "secureweb"
+)
+
+func SetProxy(ip string, port string) error {
+	// Get the active network interface
+	activeInterface, err := getActiveNetworkInterface()
+	if err != nil {
+		return err
+	}
+
+	// Set the web proxy and secure web proxy
+	if err := setProxyCommand(httpProxyType, activeInterface, ip, port); err != nil {
+		return err
+	}
+	if err := setProxyCommand(httpsProxyType, activeInterface, ip, port); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func UnsetProxy() error {
+	// Get the active network interface
+	activeInterface, err := getActiveNetworkInterface()
+	if err != nil {
+		return err
+	}
+
+	// Unset the web proxy and secure web proxy
+	if err := removeProxyCommand(httpProxyType, activeInterface); err != nil {
+		return err
+	}
+	if err := removeProxyCommand(httpsProxyType, activeInterface); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// getActiveNetworkInterface finds the active network interface using shell commands.
+// https://keith.github.io/xcode-man-pages/networksetup.8.html#listnetworkserviceorder
+func getActiveNetworkInterface() (string, error) {
+	cmd := "networksetup -listnetworkserviceorder | grep `route -n get 0.0.0.0 | grep 'interface' | cut -d ':' -f2` -B 1 | head -n 1 | cut -d ' ' -f2"
+	out, err := exec.Command("bash", "-c", cmd).Output()
+	if err != nil {
+		return "", err
+	}
+	return strings.TrimSpace(string(out)), nil
+}
+
+// setProxyCommand sets the specified type of proxy on the given network interface.
+// https://keith.github.io/xcode-man-pages/networksetup.8.html#getsecurewebproxy
+func setProxyCommand(ptype ProxyType, interfaceName string, ip string, port string) error {
+	cmdStr := fmt.Sprintf("networksetup -set%sproxy \"%s\" %s %s", ptype, interfaceName, ip, port)
+	cmd := exec.Command("bash", "-c", cmdStr)
+	var stderr bytes.Buffer
+	cmd.Stderr = &stderr
+
+	return runCommand(cmdStr)
+}
+
+// removeProxyCommand unsets the specified type of proxy from the given network interface.
+// https://keith.github.io/xcode-man-pages/networksetup.8.html#setwebproxystate
+func removeProxyCommand(ptype ProxyType, interfaceName string) error {
+	cmdStr := fmt.Sprintf("networksetup -set%sproxystate \"%s\" off", ptype, interfaceName)
+	cmd := exec.Command("bash", "-c", cmdStr)
+	var stderr bytes.Buffer
+	cmd.Stderr = &stderr
+
+	return runCommand(cmdStr)
+}
+
+func runCommand(cmdStr string) error {
+	cmd := exec.Command("bash", "-c", cmdStr)
+	var stderr bytes.Buffer
+	cmd.Stderr = &stderr
+
+	err := cmd.Run()
+	if err != nil {
+		return fmt.Errorf("%v: %s", err, stderr.String())
+	}
+	return nil
+}

x/sysproxy/sysproxy_linux.go

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+// Copyright 2024 Jigsaw Operations LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build linux
+
+package sysproxy
+
+import (
+	"fmt"
+	"os/exec"
+)
+
+type ProxyType string
+
+const (
+	httpProxyType  ProxyType = "http"
+	httpsProxyType ProxyType = "https"
+	ftpProxyType   ProxyType = "ftp"
+)
+
+func SetProxy(ip string, port string) error {
+	// Execute Linux specific commands to set proxy
+	if err := setManualMode(); err != nil {
+		return err
+	}
+	if err := setWebProxy(httpProxyType, ip, port); err != nil {
+		return err
+	}
+	if err := setWebProxy(httpsProxyType, ip, port); err != nil {
+		return err
+	}
+	if err := setWebProxy(ftpProxyType, ip, port); err != nil {
+		return err
+	}
+	return nil
+}
+
+func setManualMode() error {
+	return execCommand("gsettings", "set", "org.gnome.system.proxy", "mode", "manual")
+}
+
+func setWebProxy(pType ProxyType, ip string, port string) error {
+	p := fmt.Sprintf("org.gnome.system.proxy.%s", pType)
+	if err := execCommand("gsettings", "set", p, "host", ip); err != nil {
+		return err
+	}
+	if err := execCommand("gsettings", "set", p, "port", port); err != nil {
+		return err
+	}
+	return nil
+}
+
+func UnsetProxy() error {
+	// Execute Linux specific commands to unset proxy
+	return execCommand("gsettings", "set", "org.gnome.system.proxy", "mode", "none")
+}
+
+func execCommand(name string, arg ...string) error {
+	cmd := exec.Command(name, arg...)
+	err := cmd.Run()
+	if err != nil {
+		return fmt.Errorf("failed to execute command: %w", err)
+	}
+	return nil
+}

x/sysproxy/sysproxy_other.go

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+// Copyright 2024 Jigsaw Operations LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build !linux && !windows && !darwin
+
+package sysproxy
+
+import "errors"
+
+// SetProxy does nothing on unsupported platforms.
+func SetProxy(ip string, port string) error {
+	return errors.New("unsupported platform")
+}
+
+// SetProxy does nothing on unsupported platforms.
+func UnsetProxy() error {
+	return errors.New("unsupported platform")
+}

x/sysproxy/sysproxy_windows.go

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+// Copyright 2024 Jigsaw Operations LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//go:build windows
+
+package sysproxy
+
+import (
+	"errors"
+	"fmt"
+
+	"golang.org/x/sys/windows"
+	"golang.org/x/sys/windows/registry"
+)
+
+var (
+	modwininet            = windows.NewLazySystemDLL("wininet.dll")
+	procInternetSetOption = modwininet.NewProc("InternetSetOptionW")
+)
+
+// https://learn.microsoft.com/en-us/windows/win32/wininet/option-flags
+// INTERNET_OPTION_SETTINGS_CHANGED: 39
+// Notifies the system that the registry settings have been changed so that it verifies the settings on the next call to InternetConnect.
+// INTERNET_OPTION_REFRESH: 37
+// Causes the proxy data to be reread from the registry for a handle. No buffer is required.
+// This option can be used on the HINTERNET handle returned by InternetOpen.
+// This is used by InternetSetOption.
+const (
+	INTERNET_OPTION_SETTINGS_CHANGED = 39
+	INTERNET_OPTION_REFRESH          = 37
+)
+
+// https://learn.microsoft.com/en-us/windows/win32/api/wininet/nf-wininet-internetsetoptionw
+// internetSetOption sets an Internet option.
+func internetSetOption(hInternet uintptr, dwOption int, lpBuffer uintptr, dwBufferLength uint32) bool {
+	ret, _, _ := procInternetSetOption.Call(
+		hInternet,
+		uintptr(dwOption),
+		lpBuffer,
+		uintptr(dwBufferLength),
+	)
+	return ret != 0
+}
+
+func resetWininetProxySettings() error {
+
+	result1 := internetSetOption(0, INTERNET_OPTION_SETTINGS_CHANGED, 0, 0)
+	result2 := internetSetOption(0, INTERNET_OPTION_REFRESH, 0, 0)
+
+	if result1 && result2 {
+		fmt.Println("Operation successful")
+		return nil
+	} else {
+		fmt.Println("Operation failed")
+		return errors.New("Wininet setting change operation failed")
+	}
+}
+
+func SetProxy(ip string, port string) error {
+	key, err := registry.OpenKey(registry.CURRENT_USER, `Software\Microsoft\Windows\CurrentVersion\Internet Settings`, registry.SET_VALUE)
+	if err != nil {
+		return err
+	}
+	defer key.Close()
+
+	values := map[string]interface{}{
+		"MigrateProxy":  1,
+		"ProxyEnable":   1,
+		"ProxyHttp1.1":  0,
+		"ProxyServer":   fmt.Sprintf("%s:%s", ip, port),
+		"ProxyOverride": "*.local;<local>",
+	}
+
+	for name, value := range values {
+		switch v := value.(type) {
+		case int:
+			err = key.SetDWordValue(name, uint32(v))
+		case string:
+			err = key.SetStringValue(name, v)
+		default:
+			return fmt.Errorf("unsupported value type")
+		}
+		if err != nil {
+			return err
+		}
+	}
+
+	// Refresh the settings
+	err = resetWininetProxySettings()
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func UnsetProxy() error {
+	key, err := registry.OpenKey(registry.CURRENT_USER, `Software\Microsoft\Windows\CurrentVersion\Internet Settings`, registry.SET_VALUE)
+	if err != nil {
+		return err
+	}
+	defer key.Close()
+
+	// Set ProxyEnable to 0 and ProxyServer to an empty string
+	err = key.SetDWordValue("ProxyEnable", 0)
+	if err != nil {
+		return err
+	}
+	err = key.SetStringValue("ProxyServer", "")
+	if err != nil {
+		return err
+	}
+
+	// Refresh the settings
+	err = resetWininetProxySettings()
+	if err != nil {
+		return err
+	}
+
+	return nil
+}