move udpproxy files into repo root

validator.go

@@ -0,0 +1,65 @@
+package udpproxy
+
+import "bytes"
+
+type validator struct {
+	rconRequestHeader         []byte
+	getstatusRequestHeader    []byte
+	getinfoRequestHeader      []byte
+	getchallengeRequestHeader []byte
+	rconResponseHeader        []byte
+	getstatusResponseHeader   []byte
+	getinfoResponseHeader     []byte
+	badRconIdentifier         []byte
+}
+
+func newValidator() validator {
+	return validator{
+		rconRequestHeader:         []byte("\xff\xff\xff\xffrcon"),
+		getstatusRequestHeader:    []byte("\xff\xff\xff\xffgetstatus"),
+		getinfoRequestHeader:      []byte("\xff\xff\xff\xffgetinfo"),
+		getchallengeRequestHeader: []byte("\xff\xff\xff\xffgetchallenge"),
+		rconResponseHeader:        []byte("\xff\xff\xff\xffprint\n"),
+		getstatusResponseHeader:   []byte("\xff\xff\xff\xffstatusResponse\n"),
+		getinfoResponseHeader:     []byte("\xff\xff\xff\xffinfoResponse\n"),
+		badRconIdentifier:         []byte("Bad rcon"),
+	}
+}
+
+func (v validator) compare(buf, c []byte) bool {
+	return bytes.Equal(buf[:len(c)], c)
+}
+
+func (v validator) isRconRequestPacket(buf []byte) bool {
+	return v.compare(buf, v.rconRequestHeader)
+}
+
+func (v validator) isQueryRequestPacket(buf []byte) bool {
+	return v.compare(buf, v.getstatusRequestHeader) ||
+		v.compare(buf, v.getinfoRequestHeader)
+}
+
+func (v validator) isValidRequestPacket(buf []byte) bool {
+	return v.isRconRequestPacket(buf) || v.isQueryRequestPacket(buf)
+}
+
+func (v validator) isChallengeRequestPacket(buf []byte) bool {
+	return v.compare(buf, v.getchallengeRequestHeader)
+}
+
+func (v validator) isRconResponsePacket(buf []byte) bool {
+	return v.compare(buf, v.rconResponseHeader)
+}
+
+func (v validator) isQueryResponsePacket(buf []byte) bool {
+	return v.compare(buf, v.getstatusResponseHeader) ||
+		v.compare(buf, v.getinfoResponseHeader)
+}
+
+func (v validator) isValidResponsePacket(buf []byte) bool {
+	return v.isRconResponsePacket(buf) || v.isQueryResponsePacket(buf)
+}
+
+func (v validator) isBadRconResponse(buf []byte) bool {
+	return v.compare(buf[len(v.rconResponseHeader):], v.badRconIdentifier)
+}