feat: add signtool to plugin repository

- Migrate signing tool from GoTunnel main project
- Self-contained, no external dependencies
- Updated CI workflow to build locally

tools/signtool/main.go

@@ -0,0 +1,106 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/gotunnel/plugins/tools/signtool/sign"
+)
+
+func main() {
+	if len(os.Args) < 2 {
+		printUsage()
+		os.Exit(1)
+	}
+
+	switch os.Args[1] {
+	case "keygen":
+		cmdKeygen()
+	case "sign":
+		cmdSign(os.Args[2:])
+	default:
+		printUsage()
+		os.Exit(1)
+	}
+}
+
+func printUsage() {
+	fmt.Println("GoTunnel Plugin Sign Tool")
+	fmt.Println()
+	fmt.Println("Usage:")
+	fmt.Println("  signtool keygen")
+	fmt.Println("  signtool sign -key KEY -name NAME -version VER FILE")
+}
+
+func cmdKeygen() {
+	kp, err := sign.GenerateKeyPair()
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "生成密钥失败: %v\n", err)
+		os.Exit(1)
+	}
+
+	fmt.Println("=== 密钥对已生成 ===")
+	fmt.Println()
+	fmt.Println("私钥 (请妥善保管):")
+	fmt.Println(sign.EncodePrivateKey(kp.PrivateKey))
+	fmt.Println()
+	fmt.Println("公钥 (内置到客户端):")
+	fmt.Println(sign.EncodePublicKey(kp.PublicKey))
+}
+
+func cmdSign(args []string) {
+	fs := flag.NewFlagSet("sign", flag.ExitOnError)
+	keyFile := fs.String("key", "", "私钥文件路径")
+	name := fs.String("name", "", "插件名称")
+	version := fs.String("version", "", "插件版本")
+	keyID := fs.String("keyid", "official-v1", "密钥 ID")
+	fs.Parse(args)
+
+	if *keyFile == "" || *name == "" || *version == "" || fs.NArg() < 1 {
+		fmt.Println("用法: signtool sign -key KEY -name NAME -version VER FILE")
+		os.Exit(1)
+	}
+
+	// 读取私钥
+	keyData, err := os.ReadFile(*keyFile)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "读取私钥失败: %v\n", err)
+		os.Exit(1)
+	}
+
+	privKey, err := sign.DecodePrivateKey(strings.TrimSpace(string(keyData)))
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "解析私钥失败: %v\n", err)
+		os.Exit(1)
+	}
+
+	// 读取插件文件
+	pluginFile := fs.Arg(0)
+	source, err := os.ReadFile(pluginFile)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "读取文件失败: %v\n", err)
+		os.Exit(1)
+	}
+
+	// 创建载荷并签名
+	payload := sign.CreatePayload(*name, *version, string(source), *keyID)
+	signed, err := sign.SignPlugin(privKey, payload)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "签名失败: %v\n", err)
+		os.Exit(1)
+	}
+
+	// 写入签名文件
+	sigData, _ := sign.EncodeSignedPlugin(signed)
+	sigFile := pluginFile + ".sig"
+	if err := os.WriteFile(sigFile, []byte(sigData), 0644); err != nil {
+		fmt.Fprintf(os.Stderr, "写入签名失败: %v\n", err)
+		os.Exit(1)
+	}
+
+	fmt.Printf("签名成功: %s\n", sigFile)
+	fmt.Printf("  插件: %s v%s\n", *name, *version)
+	fmt.Printf("  哈希: %s\n", payload.SourceHash)
+}