Can correctly accept faketls messages

mtglib/internal/faketls/record/record.go

@@ -0,0 +1,87 @@
+package record
+
+import (
+	"bytes"
+	"encoding/base64"
+	"encoding/binary"
+	"fmt"
+	"io"
+)
+
+type Record struct {
+	Type    Type
+	Version Version
+	Payload bytes.Buffer
+}
+
+func (r *Record) String() string {
+	return fmt.Sprintf("<tlsRecord(type=%v, version=%v, payload=%s)>",
+		r.Type,
+		r.Version,
+		base64.StdEncoding.EncodeToString(r.Payload.Bytes()))
+}
+
+func (r *Record) Reset() {
+	r.Payload.Reset()
+}
+
+func (r *Record) Read(reader io.Reader) error {
+	r.Reset()
+
+	buf := [2]byte{}
+
+	if _, err := io.ReadFull(reader, buf[:1]); err != nil {
+		return fmt.Errorf("cannot read type: %w", err)
+	}
+
+	r.Type = Type(buf[0])
+	if err := r.Type.Valid(); err != nil {
+		return fmt.Errorf("invalid type: %w", err)
+	}
+
+	if _, err := io.ReadFull(reader, buf[:]); err != nil {
+		return fmt.Errorf("cannot read version: %w", err)
+	}
+
+	r.Version = Version(binary.BigEndian.Uint16(buf[:]))
+	if err := r.Version.Valid(); err != nil {
+		return fmt.Errorf("invalid version: %w", err)
+	}
+
+	if _, err := io.ReadFull(reader, buf[:]); err != nil {
+		return fmt.Errorf("cannot read payload length: %w", err)
+	}
+
+	length := int64(binary.BigEndian.Uint16(buf[:]))
+	if _, err := io.CopyN(&r.Payload, reader, length); err != nil {
+		return fmt.Errorf("cannot read payload: %w", err)
+	}
+
+	return nil
+}
+
+func (r *Record) Dump(writer io.Writer) error {
+	buf := [2]byte{byte(r.Type), 0}
+
+	if _, err := writer.Write(buf[:1]); err != nil {
+		return fmt.Errorf("cannot dump type: %w", err)
+	}
+
+	binary.BigEndian.PutUint16(buf[:], uint16(r.Version))
+
+	if _, err := writer.Write(buf[:]); err != nil {
+		return fmt.Errorf("cannot dump version: %w", err)
+	}
+
+	binary.BigEndian.PutUint16(buf[:], uint16(r.Payload.Len()))
+
+	if _, err := writer.Write(buf[:]); err != nil {
+		return fmt.Errorf("cannot dump payload length: %w", err)
+	}
+
+	if _, err := writer.Write(r.Payload.Bytes()); err != nil {
+		return fmt.Errorf("cannot dump payload: %w", err)
+	}
+
+	return nil
+}