diff --git a/internal/protocols/doq/doq.go b/internal/protocols/doq/doq.go index 123b02c..936d0eb 100644 --- a/internal/protocols/doq/doq.go +++ b/internal/protocols/doq/doq.go @@ -1,3 +1,117 @@ package doq -// DoQ (DNS over QUIC) resolver implementation +import ( + "bytes" + "context" + "crypto/tls" + "encoding/binary" + "fmt" + "io" + "os" + + "github.com/afonsofrancof/sdns-perf/internal/protocols/do53" + "github.com/miekg/dns" + "github.com/quic-go/quic-go" +) + +type DoQClient struct { + target string + keyLogFile *os.File + tlsConfig *tls.Config +} + +func New(target string) (*DoQClient, error) { + keyLogFile, err := os.OpenFile( + "tls-key-log.txt", + os.O_APPEND|os.O_CREATE|os.O_WRONLY, + 0600, + ) + if err != nil { + return nil, fmt.Errorf("failed opening key log file: %v", err) + } + + tlsConfig := &tls.Config{ + // FIX: Actually check the domain name + InsecureSkipVerify: true, + MinVersion: tls.VersionTLS13, + KeyLogWriter: keyLogFile, + NextProtos: []string{"doq"}, + } + + return &DoQClient{ + target: target, + keyLogFile: keyLogFile, + tlsConfig: tlsConfig, + }, nil +} + +func (c *DoQClient) Close() { + if c.keyLogFile != nil { + c.keyLogFile.Close() + } +} + +func (c *DoQClient) Query(domain, queryType string, dnssec bool) error { + quicConn, err := quic.DialAddr(context.Background(), c.target, c.tlsConfig, &quic.Config{}) + if err != nil { + return fmt.Errorf("failed to establish QUIC connection: %v", err) + } + defer quicConn.CloseWithError(0, "") + + DNSMessage, err := do53.NewDNSMessage(domain, queryType) + if err != nil { + return err + } + + quicStream, err := quicConn.OpenStreamSync(context.Background()) + if err != nil { + return fmt.Errorf("failed to opening QUIC stream: %v", err) + } + defer quicStream.Close() + + var lengthPrefixedMessage bytes.Buffer + err = binary.Write(&lengthPrefixedMessage, binary.BigEndian, uint16(len(DNSMessage))) + if err != nil { + return fmt.Errorf("failed to write message length: %v", err) + } + _, err = lengthPrefixedMessage.Write(DNSMessage) + if err != nil { + return fmt.Errorf("failed to write DNS message: %v", err) + } + + _, err = quicStream.Write(lengthPrefixedMessage.Bytes()) + if err != nil { + return fmt.Errorf("failed writing to QUIC stream: %v", err) + } + + lengthBuf := make([]byte, 2) + _, err = io.ReadFull(quicStream, lengthBuf) + if err != nil { + return fmt.Errorf("failed reading response length: %v", err) + } + + messageLength := binary.BigEndian.Uint16(lengthBuf) + if messageLength == 0 { + return fmt.Errorf("received zero-length message") + } + + responseBuf := make([]byte, messageLength) + _, err = io.ReadFull(quicStream, responseBuf) + if err != nil { + return fmt.Errorf("failed reading response data: %v", err) + } + + recvMsg := new(dns.Msg) + err = recvMsg.Unpack(responseBuf) + if err != nil { + return fmt.Errorf("failed to parse DNS response: %v", err) + } + + // TODO: Check if the response had no errors or TD bit set + + for _, answer := range recvMsg.Answer { + fmt.Println(answer.String()) + } + + return nil +}