text: // Copyright 2011 The Go Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style
  // license that can be found in the LICENSE file.
  
  package packet
  
  import (
  	"encoding/binary"
  	"io"
  )
  
  // LiteralData represents an encrypted file. See RFC 4880, section 5.9.
  type LiteralData struct {
  	IsBinary bool
  	FileName string
  	Time     uint32 // Unix epoch time. Either creation time or modification time. 0 means undefined.
  	Body     io.Reader
  }
  
  // ForEyesOnly returns whether the contents of the LiteralData have been marked
  // as especially sensitive.
  func (l *LiteralData) ForEyesOnly() bool {
  	return l.FileName == "_CONSOLE"
  }
  
  func (l *LiteralData) parse(r io.Reader) (err error) {
  	var buf [256]byte
  
  	_, err = readFull(r, buf[:2])
  	if err != nil {
  		return
  	}
  
  	l.IsBinary = buf[0] == 'b'
  	fileNameLen := int(buf[1])
  
  	_, err = readFull(r, buf[:fileNameLen])
  	if err != nil {
  		return
  	}
  
  	l.FileName = string(buf[:fileNameLen])
  
  	_, err = readFull(r, buf[:4])
  	if err != nil {
  		return
  	}
  
  	l.Time = binary.BigEndian.Uint32(buf[:4])
  	l.Body = r
  	return
  }
  
  // SerializeLiteral serializes a literal data packet to w and returns a
  // WriteCloser to which the data itself can be written and which MUST be closed
  // on completion. The fileName is truncated to 255 bytes.
  func SerializeLiteral(w io.WriteCloser, isBinary bool, fileName string, time uint32) (plaintext io.WriteCloser, err error) {
  	var buf [4]byte
  	buf[0] = 't'
  	if isBinary {
  		buf[0] = 'b'
  	}
  	if len(fileName) > 255 {
  		fileName = fileName[:255]
  	}
  	buf[1] = byte(len(fileName))
  
  	inner, err := serializeStreamHeader(w, packetTypeLiteralData)
  	if err != nil {
  		return
  	}
  
  	_, err = inner.Write(buf[:2])
  	if err != nil {
  		return
  	}
  	_, err = inner.Write([]byte(fileName))
  	if err != nil {
  		return
  	}
  	binary.BigEndian.PutUint32(buf[:], time)
  	_, err = inner.Write(buf[:])
  	if err != nil {
  		return
  	}
  
  	plaintext = inner
  	return
  }
  