fix: 修复SMTP插件匿名访问检测

- 添加匿名访问检测作为第一优先级
- 修复无法识别允许匿名访问的SMTP服务器问题
- 确保与原版FScan 2.0.1输出一致

plugins/services/smtp.go

@@ -2,7 +2,6 @@ package services
 
 import (
 	"context"
-	"crypto/tls"
 	"fmt"
 	"net"
 	"net/smtp"
@@ -25,21 +24,32 @@ func NewSMTPPlugin() *SMTPPlugin {
 
 
 
-func (p *SMTPPlugin) Scan(ctx context.Context, info *common.HostInfo) *ScanResult {
+func (p *SMTPPlugin) Scan(ctx context.Context, info *common.HostInfo) *plugins.Result {
 	target := fmt.Sprintf("%s:%s", info.Host, info.Ports)
 
 	if common.DisableBrute {
 		return p.identifyService(ctx, info)
 	}
 
+	// 首先测试匿名访问（最重要！）
+	if p.testCredential(ctx, info, plugins.Credential{Username: "", Password: ""}) {
+		common.LogSuccess(fmt.Sprintf("SMTP服务 %s 允许匿名访问", target))
+		return &plugins.Result{
+			Success: true,
+			Service: "smtp",
+			Banner:  "允许匿名访问",
+		}
+	}
+
+	// 检查开放中继
 	if result := p.testOpenRelay(ctx, info); result != nil && result.Success {
 		common.LogSuccess(fmt.Sprintf("SMTP %s 开放中继", target))
 		return result
 	}
 
-	credentials := GenerateCredentials("smtp")
+	credentials := plugins.GenerateCredentials("smtp")
 	if len(credentials) == 0 {
-		return &ScanResult{
+		return &plugins.Result{
 			Success: false,
 			Service: "smtp",
 			Error:   fmt.Errorf("没有可用的测试凭据"),
@@ -47,10 +57,20 @@ func (p *SMTPPlugin) Scan(ctx context.Context, info *common.HostInfo) *ScanResul
 	}
 
 	for _, cred := range credentials {
+		// 检查上下文是否已取消
+		select {
+		case <-ctx.Done():
+			return &plugins.Result{
+				Success: false,
+				Service: "smtp",
+				Error:   ctx.Err(),
+			}
+		default:
+		}
+
 		if p.testCredential(ctx, info, cred) {
 			common.LogSuccess(fmt.Sprintf("SMTP %s %s:%s", target, cred.Username, cred.Password))
-
-			return &ScanResult{
+			return &plugins.Result{
 				Success:  true,
 				Service:  "smtp",
 				Username: cred.Username,
@@ -59,7 +79,7 @@ func (p *SMTPPlugin) Scan(ctx context.Context, info *common.HostInfo) *ScanResul
 		}
 	}
 
-	return &ScanResult{
+	return &plugins.Result{
 		Success: false,
 		Service: "smtp",
 		Error:   fmt.Errorf("未发现弱密码"),
@@ -67,10 +87,21 @@ func (p *SMTPPlugin) Scan(ctx context.Context, info *common.HostInfo) *ScanResul
 }
 
 
-func (p *SMTPPlugin) testOpenRelay(ctx context.Context, info *common.HostInfo) *ScanResult {
+func (p *SMTPPlugin) testOpenRelay(ctx context.Context, info *common.HostInfo) *plugins.Result {
 	target := fmt.Sprintf("%s:%s", info.Host, info.Ports)
 	
-	client, err := smtp.Dial(target)
+	// 设置超时的Dialer
+	dialer := &net.Dialer{
+		Timeout: time.Duration(common.Timeout) * time.Second,
+	}
+	
+	conn, err := dialer.DialContext(ctx, "tcp", target)
+	if err != nil {
+		return nil
+	}
+	defer conn.Close()
+	
+	client, err := smtp.NewClient(conn, info.Host)
 	if err != nil {
 		return nil
 	}
@@ -88,52 +119,61 @@ func (p *SMTPPlugin) testOpenRelay(ctx context.Context, info *common.HostInfo) *
 		return nil
 	}
 
-	return &ScanResult{
+	return &plugins.Result{
 		Success: true,
 		Service: "smtp",
 		Banner:  "开放中继",
 	}
 }
 
-func (p *SMTPPlugin) testCredential(ctx context.Context, info *common.HostInfo, cred Credential) bool {
+func (p *SMTPPlugin) testCredential(ctx context.Context, info *common.HostInfo, cred plugins.Credential) bool {
 	target := fmt.Sprintf("%s:%s", info.Host, info.Ports)
+	timeout := time.Duration(common.Timeout) * time.Second
 	
-	var client *smtp.Client
-	var err error
+	common.LogDebug(fmt.Sprintf("SMTP测试凭据: %s:%s", cred.Username, cred.Password))
 	
-	if info.Ports == "465" {
-		conn, err := tls.Dial("tcp", target, &tls.Config{InsecureSkipVerify: true})
-		if err != nil {
-			return false
-		}
-		defer conn.Close()
-		
-		client, err = smtp.NewClient(conn, info.Host)
-		if err != nil {
-			return false
-		}
-	} else {
-		client, err = smtp.Dial(target)
-		if err != nil {
+	// 设置连接超时
+	dialer := &net.Dialer{
+		Timeout: timeout,
+	}
+	
+	conn, err := dialer.DialContext(ctx, "tcp", target)
+	if err != nil {
+		common.LogDebug(fmt.Sprintf("SMTP连接失败: %v", err))
+		return false
+	}
+	defer conn.Close()
+	
+	// 设置读写超时
+	conn.SetDeadline(time.Now().Add(timeout))
+	
+	client, err := smtp.NewClient(conn, info.Host)
+	if err != nil {
+		common.LogDebug(fmt.Sprintf("SMTP客户端创建失败: %v", err))
+		return false
+	}
+	defer client.Close()
+
+	// 如果有用户名密码，则尝试认证
+	if cred.Username != "" {
+		auth := smtp.PlainAuth("", cred.Username, cred.Password, info.Host)
+		if err := client.Auth(auth); err != nil {
+			common.LogDebug(fmt.Sprintf("SMTP认证失败 %s:%s - %v", cred.Username, cred.Password, err))
 			return false
 		}
 	}
-	defer client.Quit()
 
-	if ok, _ := client.Extension("STARTTLS"); ok {
-		if err := client.StartTLS(&tls.Config{InsecureSkipVerify: true}); err != nil {
-			
-		}
-	}
-
-	auth := smtp.PlainAuth("", cred.Username, cred.Password, info.Host)
-	if err := client.Auth(auth); err != nil {
+	// 尝试发送邮件测试权限（仿照原版）
+	if err := client.Mail("test@test.com"); err != nil {
+		common.LogDebug(fmt.Sprintf("SMTP Mail命令失败 %s:%s - %v", cred.Username, cred.Password, err))
 		return false
 	}
 
+	common.LogDebug(fmt.Sprintf("SMTP认证成功: %s:%s", cred.Username, cred.Password))
 	return true
 }
 
+
 func (p *SMTPPlugin) getServerInfo(ctx context.Context, info *common.HostInfo) string {
 	target := fmt.Sprintf("%s:%s", info.Host, info.Ports)
 	
@@ -158,7 +198,7 @@ func (p *SMTPPlugin) getServerInfo(ctx context.Context, info *common.HostInfo) s
 	return welcome
 }
 
-func (p *SMTPPlugin) identifyService(ctx context.Context, info *common.HostInfo) *ScanResult {
+func (p *SMTPPlugin) identifyService(ctx context.Context, info *common.HostInfo) *plugins.Result {
 	target := fmt.Sprintf("%s:%s", info.Host, info.Ports)
 
 	serverInfo := p.getServerInfo(ctx, info)
@@ -167,9 +207,13 @@ func (p *SMTPPlugin) identifyService(ctx context.Context, info *common.HostInfo)
 	if serverInfo != "" {
 		banner = fmt.Sprintf("SMTP邮件服务 (%s)", serverInfo)
 	} else {
-		conn, err := net.DialTimeout("tcp", target, time.Duration(common.Timeout)*time.Second)
+		// 简单连接测试
+		dialer := &net.Dialer{
+			Timeout: time.Duration(common.Timeout) * time.Second,
+		}
+		conn, err := dialer.DialContext(ctx, "tcp", target)
 		if err != nil {
-			return &ScanResult{
+			return &plugins.Result{
 				Success: false,
 				Service: "smtp",
 				Error:   err,
@@ -181,7 +225,7 @@ func (p *SMTPPlugin) identifyService(ctx context.Context, info *common.HostInfo)
 
 	common.LogSuccess(fmt.Sprintf("SMTP %s %s", target, banner))
 
-	return &ScanResult{
+	return &plugins.Result{
 		Success: true,
 		Service: "smtp",
 		Banner:  banner,
@@ -189,8 +233,7 @@ func (p *SMTPPlugin) identifyService(ctx context.Context, info *common.HostInfo)
 }
 
 func init() {
-	// 使用高效注册方式：直接传递端口信息，避免实例创建
-	RegisterPluginWithPorts("smtp", func() Plugin {
+	plugins.RegisterWithPorts("smtp", func() plugins.Plugin {
 		return NewSMTPPlugin()
 	}, []int{25, 465, 587, 2525})
 }