1 files changed, 172 insertions, 0 deletions
diff --git a/internal/wireguard.go b/internal/wireguard.go
new file mode 100644
index 0000000..ebfa0bb
--- /dev/null
+++ b/internal/wireguard.go
@@ -0,0 +1,172 @@
+package internal
+
+import (
+	"fmt"
+	"log"
+	"os/exec"
+	"path/filepath"
+	"regexp"
+	"slices"
+	"strings"
+
+	"github.com/samber/lo"
+)
+
+var interfaceRegex = regexp.MustCompile(`^interface:\s+(.+)$`)
+
+type WireGuardConnection struct {
+	Name   string `json:"name"`
+	Active bool   `json:"active"`
+}
+
+func GetStatus() (string, error) {
+	output, err := showStatus()
+	if err != nil {
+		return "", err
+	}
+	status := lo.FilterMap(strings.Split(string(output), "\n"), func(line string, _ int) (string, bool) {
+		line = strings.TrimSpace(line)
+		if strings.Contains(line, "interface") {
+			return fmt.Sprintf("Connection: %s", strings.TrimPrefix(line, "interface:")), true
+		}
+		if strings.Contains(line, "latest handshake") {
+			return fmt.Sprintf("Latest Handshake: %s", strings.TrimPrefix(line, "latest handshake:")), true
+		}
+		if strings.Contains(line, "transfer") {
+			return fmt.Sprintf("Transfer: %s", strings.TrimPrefix(line, "transfer:")), true
+		}
+		return "", false
+	})
+	// This is a simple check on whether a connection started or not.
+	// Instead of complex logic on looping on connections and figuring which connection might be missing info.
+	// NOTE: This doesn't handle if 3x connections were started and none of them is still active.
+	// NOTE: ToggleConnection stops all active connections and activate one.
+	// to avoid issues with multiple VPNs configuring the same iptable that could happen with default wireguard configs
+	if len(status)%3 != 0 {
+		status = append(status, "Connection starting...")
+	}
+	return strings.Join(status, "\n"), nil
+}
+
+func GetConnections() ([]*WireGuardConnection, error) {
+	activeConnection, err := getActiveConnections()
+	if err != nil {
+		return nil, err
+	}
+	allConnections, err := getAllConnections()
+	if err != nil {
+		return nil, err
+	}
+
+	connections := make([]*WireGuardConnection, 0, len(allConnections))
+	for _, i := range allConnections {
+		connections = append(connections, &WireGuardConnection{
+			Name:   i,
+			Active: slices.Contains(activeConnection, i),
+		})
+	}
+	return connections, nil
+}
+
+func ToggleConnection(name string) ([]byte, error) {
+	allConnections, err := GetConnections()
+	if err != nil {
+		return nil, err
+	}
+	activeConnections := lo.Filter(allConnections, func(i *WireGuardConnection, _ int) bool {
+		return i.Active
+	})
+	connection, err := getConnection(name)
+	if err != nil {
+		return nil, err
+	}
+	output, err := stopActiveConnections(activeConnections)
+	if err != nil {
+		return nil, err
+	}
+	startOutput, err := startConnection(connection)
+	if err != nil {
+		return nil, err
+	}
+	output = append(output, startOutput...)
+	return output, nil
+}
+
+func stopActiveConnections(activeConnections []*WireGuardConnection) ([]byte, error) {
+	var output []byte
+	for _, activeConnection := range activeConnections {
+		log.Printf("Stopping connection %s.", activeConnection.Name)
+		cmd := exec.Command("sudo", "wg-quick", "down", activeConnection.Name)
+		out, err := cmd.CombinedOutput()
+		if err != nil {
+			return nil, err
+		}
+		output = append(output, out...)
+		log.Printf("Successfully stopped connection %s.", activeConnection.Name)
+	}
+	return output, nil
+}
+
+func startConnection(connection *WireGuardConnection) ([]byte, error) {
+	if connection.Active {
+		return nil, nil
+	}
+	log.Printf("Starting connection %s.", connection.Name)
+	cmd := exec.Command("sudo", "wg-quick", "up", connection.Name)
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		return nil, err
+	}
+	log.Printf("Successfully started connection %s.", connection.Name)
+	return output, nil
+}
+
+// Get the list of all wireguard connections using config files
+func getAllConnections() ([]string, error) {
+	files, err := filepath.Glob("/etc/wireguard/*.conf")
+	if err != nil {
+		return nil, err
+	}
+	files = lo.Map(files, func(f string, _ int) string {
+		return strings.TrimSuffix(filepath.Base(f), filepath.Ext(f))
+	})
+	return files, nil
+}
+
+// Get the list of active wireguard connections using wg show command
+func getActiveConnections() ([]string, error) {
+	var activeConnections []string
+	status, err := showStatus()
+	if err != nil {
+		return nil, err
+	}
+	for line := range strings.SplitSeq(string(status), "\n") {
+		if matches := interfaceRegex.FindStringSubmatch(strings.TrimSpace(line)); len(matches) > 1 {
+			activeConnections = append(activeConnections, matches[1])
+		}
+	}
+	return activeConnections, nil
+}
+
+func getConnection(name string) (*WireGuardConnection, error) {
+	allConnections, err := GetConnections()
+	if err != nil {
+		return nil, err
+	}
+	connection, ok := lo.Find(allConnections, func(dev *WireGuardConnection) bool {
+		return dev.Name == name
+	})
+	if !ok {
+		return nil, fmt.Errorf("failed to find connection: %s", name)
+	}
+	return connection, nil
+}
+
+func showStatus() ([]byte, error) {
+	cmd := exec.Command("sudo", "wg", "show")
+	output, err := cmd.Output()
+	if err != nil {
+		return nil, fmt.Errorf("failed to execute wg show: %w", err)
+	}
+	return output, nil
+}