codecrafters submit [skip ci]HEADmaster

1 files changed, 60 insertions, 0 deletions

diff --git a/app/forwarder.go b/app/forwarder.go
new file mode 100644
index 0000000..c4eac58
--- /dev/null
+++ b/app/forwarder.go
@@ -0,0 +1,60 @@
+package main
+
+import (
+	"fmt"
+	"net"
+)
+
+func ForwardQuestions(addr string, questions []DNSQuestion, id uint16) []DNSAnswer {
+	answers := []DNSAnswer{}
+
+	udpConn, err := net.Dial("udp", addr)
+	if err != nil {
+		fmt.Println("Failed to connect to address:", err)
+		return answers
+	}
+
+	defer udpConn.Close()
+
+	for _, question := range questions {
+		questionBytes := question.Bytes()
+
+		header := DNSHeader{
+			ID:      id,
+			QR:      0,
+			OPCODE:  0,
+			AA:      0,
+			TC:      0,
+			RD:      1,
+			RA:      0,
+			Z:       0,
+			RCODE:   0,
+			QDCOUNT: 1,
+			ANCOUNT: 0,
+			NSCOUNT: 0,
+			ARCOUNT: 0,
+		}
+
+		headerBytes := header.Bytes()
+		buf := append(headerBytes, questionBytes...)
+
+		_, err = udpConn.Write(buf)
+		if err != nil {
+			fmt.Println("Failed to send data:", err)
+			return answers
+		}
+
+		responseBuf := make([]byte, 512)
+
+		n, err := udpConn.Read(responseBuf)
+		if err != nil {
+			fmt.Println("Failed to receive data:", err)
+			return answers
+		}
+
+		responseHeader := ParseHeader(responseBuf[:n])
+		answers = append(answers, ParseAnswers(responseBuf[:n], responseHeader.QDCOUNT, responseHeader.ANCOUNT)...)
+	}
+
+	return answers
+}