feat(dnssec): query the authoritative servers directly

common/protocols/do53/do53.go

@@ -0,0 +1,97 @@
+package do53
+
+import (
+	"fmt"
+	"net"
+	"time"
+
+	"github.com/miekg/dns"
+)
+
+type Config struct {
+	HostAndPort  string
+	DNSSEC       bool
+	WriteTimeout time.Duration
+	ReadTimeout  time.Duration
+}
+
+type Client struct {
+	hostAndPort string
+	config      Config
+}
+
+func New(config Config) (*Client, error) {
+	if config.HostAndPort == "" {
+		return nil, fmt.Errorf("do53: HostAndPort cannot be empty")
+	}
+	if config.WriteTimeout <= 0 {
+		config.WriteTimeout = 2 * time.Second
+	}
+	if config.ReadTimeout <= 0 {
+		config.ReadTimeout = 5 * time.Second
+	}
+
+	return &Client{
+		hostAndPort: config.HostAndPort,
+		config:      config,
+	}, nil
+}
+
+func (c *Client) Close() {
+}
+
+func (c *Client) createConnection() (*net.UDPConn, error) {
+	udpAddr, err := net.ResolveUDPAddr("udp", c.hostAndPort)
+	if err != nil {
+		return nil, fmt.Errorf("failed to resolve UDP address: %w", err)
+	}
+
+	return net.DialUDP("udp", nil, udpAddr)
+}
+
+func (c *Client) Query(msg *dns.Msg) (*dns.Msg, error) {
+	// Create connection for this query
+	conn, err := c.createConnection()
+	if err != nil {
+		return nil, fmt.Errorf("do53: failed to create connection: %w", err)
+	}
+	defer conn.Close()
+
+	if c.config.DNSSEC {
+		msg.SetEdns0(4096, true)
+	}
+
+	packedMsg, err := msg.Pack()
+
+	if err != nil {
+		return nil, fmt.Errorf("do53: failed to pack DNS message: %w", err)
+	}
+
+	// Send query
+	if err := conn.SetWriteDeadline(time.Now().Add(c.config.WriteTimeout)); err != nil {
+		return nil, fmt.Errorf("do53: failed to set write deadline: %w", err)
+	}
+
+	if _, err := conn.Write(packedMsg); err != nil {
+		return nil, fmt.Errorf("do53: failed to send DNS query: %w", err)
+	}
+
+	// Read response
+	if err := conn.SetReadDeadline(time.Now().Add(c.config.ReadTimeout)); err != nil {
+		return nil, fmt.Errorf("do53: failed to set read deadline: %w", err)
+	}
+
+	buffer := make([]byte, dns.MaxMsgSize)
+	n, err := conn.Read(buffer)
+	if err != nil {
+		return nil, fmt.Errorf("do53: failed to read DNS response: %w", err)
+	}
+
+	// Parse response
+	response := new(dns.Msg)
+	if err := response.Unpack(buffer[:n]); err != nil {
+		return nil, fmt.Errorf("do53: failed to unpack DNS response: %w", err)
+	}
+
+	return response, nil
+}