Add native protocol service plugins

plugins/services/tftp.go

@@ -0,0 +1,95 @@
+//go:build plugin_tftp || !plugin_selective
+
+package services
+
+import (
+	"context"
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/shadow1ng/fscan/common"
+	"github.com/shadow1ng/fscan/plugins"
+)
+
+type TFTPPlugin struct {
+	plugins.BasePlugin
+}
+
+func NewTFTPPlugin() *TFTPPlugin {
+	return &TFTPPlugin{BasePlugin: plugins.NewBasePlugin("tftp")}
+}
+
+func (p *TFTPPlugin) Scan(ctx context.Context, info *common.HostInfo, session *common.ScanSession) *ScanResult {
+	timeout := session.Config.Timeout
+	if timeout <= 0 {
+		timeout = 3 * time.Second
+	}
+
+	target := fmt.Sprintf("%s:%d", info.Host, info.Port)
+	conn, err := session.DialUDP(ctx, target, timeout)
+	if err != nil {
+		return &ScanResult{Success: false, Service: "tftp"}
+	}
+	defer conn.Close()
+
+	if _, err := conn.Write(buildTFTPReadRequest("probe")); err != nil {
+		return &ScanResult{Success: false, Service: "tftp"}
+	}
+
+	buf := make([]byte, 516)
+	n, err := conn.Read(buf)
+	if err != nil || n < 4 {
+		return &ScanResult{Success: false, Service: "tftp"}
+	}
+
+	banner, ok := parseTFTPResponse(buf[:n])
+	if !ok {
+		return &ScanResult{Success: false, Service: "tftp"}
+	}
+
+	return &ScanResult{
+		Success: true,
+		Type:    plugins.ResultTypeService,
+		Service: "tftp",
+		Banner:  banner,
+	}
+}
+
+func buildTFTPReadRequest(filename string) []byte {
+	req := []byte{0x00, 0x01}
+	req = append(req, filename...)
+	req = append(req, 0x00)
+	req = append(req, "octet"...)
+	req = append(req, 0x00)
+	return req
+}
+
+func parseTFTPResponse(data []byte) (string, bool) {
+	if len(data) < 4 || data[0] != 0x00 {
+		return "", false
+	}
+
+	opcode := data[1]
+	switch opcode {
+	case 0x03:
+		return "TFTP DATA response", true
+	case 0x05:
+		msg := strings.TrimRight(string(data[4:]), "\x00")
+		if len(msg) > 160 {
+			msg = msg[:160]
+		}
+		if msg == "" {
+			msg = "error response"
+		}
+		return fmt.Sprintf("TFTP %s", msg), true
+	default:
+		return "", false
+	}
+}
+
+func init() {
+	RegisterUDPPluginWithPorts("tftp", func() Plugin {
+		return NewTFTPPlugin()
+	}, []int{69})
+}