feat: complete basic functions

Support http,dns and mysql connection. Support custom http, dns response. Support dns rebinding.
Support mysql load local files and jdbc deserialize exploit.

internal/newdns/resolver.go

@@ -0,0 +1,120 @@
+package newdns
+
+import (
+	"net"
+
+	"github.com/miekg/dns"
+)
+
+var fakeAddr = &net.TCPAddr{
+	IP:   net.IP{0, 0, 0, 0},
+	Port: 0,
+}
+
+type responseWriter struct {
+	msg *dns.Msg
+}
+
+func (w *responseWriter) LocalAddr() net.Addr {
+	return fakeAddr
+}
+
+func (w *responseWriter) RemoteAddr() net.Addr {
+	return fakeAddr
+}
+
+func (w *responseWriter) WriteMsg(msg *dns.Msg) error {
+	// check message
+	if w.msg != nil {
+		panic("message already set")
+	}
+
+	// set message
+	w.msg = msg
+
+	return nil
+}
+
+func (w *responseWriter) Write([]byte) (int, error) {
+	panic("not implemented")
+}
+
+func (w *responseWriter) Close() error {
+	return nil
+}
+
+func (w *responseWriter) TsigStatus() error {
+	panic("not implemented")
+}
+
+func (w *responseWriter) TsigTimersOnly(bool) {
+	panic("not implemented")
+}
+
+func (w *responseWriter) Hijack() {
+	panic("not implemented")
+}
+
+// Resolver returns a very primitive recursive resolver that uses the provided
+// handler to resolve all names.
+func Resolver(handler dns.Handler) dns.Handler {
+	return dns.HandlerFunc(func(w dns.ResponseWriter, req *dns.Msg) {
+		// forward query if no recursion is desired
+		if !req.RecursionDesired {
+			handler.ServeDNS(w, req)
+			return
+		}
+
+		// prepare response
+		res := new(dns.Msg)
+		res.SetReply(req)
+		res.RecursionAvailable = true
+
+		// query handler
+		var wr responseWriter
+		handler.ServeDNS(&wr, req)
+
+		// check response
+		if wr.msg == nil {
+			_ = w.WriteMsg(res)
+			return
+		}
+
+		// add resolved answers
+		res.Answer = append(res.Answer, resolve(handler, wr.msg.Answer)...)
+
+		// write response
+		err := w.WriteMsg(res)
+		if err != nil {
+			_ = w.Close()
+		}
+	})
+}
+
+func resolve(handler dns.Handler, records []dns.RR) []dns.RR {
+	// prepare result
+	var res []dns.RR
+	res = append(res, records...)
+
+	// handle records
+	for _, record := range records {
+		if cname, ok := record.(*dns.CNAME); ok {
+			// query handler
+			var wr responseWriter
+			handler.ServeDNS(&wr, &dns.Msg{
+				Question: []dns.Question{
+					{
+						Name:   cname.Target,
+						Qtype:  dns.TypeA,
+						Qclass: dns.ClassINET,
+					},
+				},
+			})
+
+			// add resolved answers
+			res = append(res, resolve(handler, wr.msg.Answer)...)
+		}
+	}
+
+	return res
+}