org.apache.poi.poifs.filesystem.Ole10Native Maven / Gradle / Ivy
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this work for additional information regarding copyright ownership.
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(the "License"); you may not use this file except in compliance with
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package org.apache.poi.poifs.filesystem;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import org.apache.poi.util.LittleEndian;
import org.apache.poi.util.LittleEndianConsts;
import org.apache.poi.util.LittleEndianOutputStream;
import org.apache.poi.util.StringUtil;
/**
* Represents an Ole10Native record which is wrapped around certain binary
* files being embedded in OLE2 documents.
*
* @author Rainer Schwarze
*/
public class Ole10Native {
public static final String OLE10_NATIVE = "\u0001Ole10Native";
protected static final String ISO1 = "ISO-8859-1";
// (the fields as they appear in the raw record:)
private int totalSize; // 4 bytes, total size of record not including this field
private short flags1 = 2; // 2 bytes, unknown, mostly [02 00]
private String label; // ASCIIZ, stored in this field without the terminating zero
private String fileName; // ASCIIZ, stored in this field without the terminating zero
private short flags2 = 0; // 2 bytes, unknown, mostly [00 00]
private short unknown1 = 3; // see below
private String command; // ASCIIZ, stored in this field without the terminating zero
private byte[] dataBuffer; // varying size, the actual native data
private short flags3 = 0; // some final flags? or zero terminators?, sometimes not there
/**
* the field encoding mode - merely a try-and-error guess ...
**/
private enum EncodingMode {
/**
* the data is stored in parsed format - including label, command, etc.
*/
parsed,
/**
* the data is stored raw after the length field
*/
unparsed,
/**
* the data is stored raw after the length field and the flags1 field
*/
compact;
}
private EncodingMode mode;
/**
* Creates an instance of this class from an embedded OLE Object. The OLE Object is expected
* to include a stream "{01}Ole10Native" which contains the actual
* data relevant for this class.
*
* @param poifs POI Filesystem object
* @return Returns an instance of this class
* @throws IOException on IO error
* @throws Ole10NativeException on invalid or unexcepted data format
*/
public static Ole10Native createFromEmbeddedOleObject(POIFSFileSystem poifs) throws IOException, Ole10NativeException {
return createFromEmbeddedOleObject(poifs.getRoot());
}
/**
* Creates an instance of this class from an embedded OLE Object. The OLE Object is expected
* to include a stream "{01}Ole10Native" which contains the actual
* data relevant for this class.
*
* @param directory POI Filesystem object
* @return Returns an instance of this class
* @throws IOException on IO error
* @throws Ole10NativeException on invalid or unexcepted data format
*/
public static Ole10Native createFromEmbeddedOleObject(DirectoryNode directory) throws IOException, Ole10NativeException {
DocumentEntry nativeEntry =
(DocumentEntry)directory.getEntry(OLE10_NATIVE);
byte[] data = new byte[nativeEntry.getSize()];
int readBytes = directory.createDocumentInputStream(nativeEntry).read(data);
assert(readBytes == data.length);
return new Ole10Native(data, 0);
}
/**
* Creates an instance and fills the fields based on ... the fields
*/
public Ole10Native(String label, String filename, String command, byte[] data) {
setLabel(label);
setFileName(filename);
setCommand(command);
setDataBuffer(data);
mode = EncodingMode.parsed;
}
/**
* Creates an instance and fills the fields based on the data in the given buffer.
*
* @param data The buffer containing the Ole10Native record
* @param offset The start offset of the record in the buffer
* @param plain as of POI 3.11 this parameter is ignored
* @throws Ole10NativeException on invalid or unexcepted data format
*
* @deprecated parameter plain is ignored, use {@link #Ole10Native(byte[],int)}
*/
public Ole10Native(byte[] data, int offset, boolean plain) throws Ole10NativeException {
this(data, offset);
}
/**
* Creates an instance and fills the fields based on the data in the given buffer.
*
* @param data The buffer containing the Ole10Native record
* @param offset The start offset of the record in the buffer
* @throws Ole10NativeException on invalid or unexcepted data format
*/
public Ole10Native(byte[] data, int offset) throws Ole10NativeException {
int ofs = offset; // current offset, initialized to start
if (data.length < offset + 2) {
throw new Ole10NativeException("data is too small");
}
totalSize = LittleEndian.getInt(data, ofs);
ofs += LittleEndianConsts.INT_SIZE;
mode = EncodingMode.unparsed;
if (LittleEndian.getShort(data, ofs) == 2) {
// some files like equations don't have a valid filename,
// but somehow encode the formula right away in the ole10 header
if (Character.isISOControl(data[ofs+LittleEndianConsts.SHORT_SIZE])) {
mode = EncodingMode.compact;
} else {
mode = EncodingMode.parsed;
}
}
int dataSize;
switch (mode) {
case parsed: {
flags1 = LittleEndian.getShort(data, ofs);
// structured format
ofs += LittleEndianConsts.SHORT_SIZE;
int len = getStringLength(data, ofs);
label = StringUtil.getFromCompressedUnicode(data, ofs, len - 1);
ofs += len;
len = getStringLength(data, ofs);
fileName = StringUtil.getFromCompressedUnicode(data, ofs, len - 1);
ofs += len;
flags2 = LittleEndian.getShort(data, ofs);
ofs += LittleEndianConsts.SHORT_SIZE;
unknown1 = LittleEndian.getShort(data, ofs);
ofs += LittleEndianConsts.SHORT_SIZE;
len = LittleEndian.getInt(data, ofs);
ofs += LittleEndianConsts.INT_SIZE;
command = StringUtil.getFromCompressedUnicode(data, ofs, len - 1);
ofs += len;
if (totalSize < ofs) {
throw new Ole10NativeException("Invalid Ole10Native");
}
dataSize = LittleEndian.getInt(data, ofs);
ofs += LittleEndianConsts.INT_SIZE;
if (dataSize < 0 || totalSize - (ofs - LittleEndianConsts.INT_SIZE) < dataSize) {
throw new Ole10NativeException("Invalid Ole10Native");
}
break;
}
case compact:
flags1 = LittleEndian.getShort(data, ofs);
ofs += LittleEndianConsts.SHORT_SIZE;
dataSize = totalSize - LittleEndianConsts.SHORT_SIZE;
break;
default:
case unparsed:
dataSize = totalSize;
break;
}
dataBuffer = new byte[dataSize];
System.arraycopy(data, ofs, dataBuffer, 0, dataSize);
ofs += dataSize;
}
/*
* Helper - determine length of zero terminated string (ASCIIZ).
*/
private static int getStringLength(byte[] data, int ofs) {
int len = 0;
while (len + ofs < data.length && data[ofs + len] != 0) {
len++;
}
len++;
return len;
}
/**
* Returns the value of the totalSize field - the total length of the
* structure is totalSize + 4 (value of this field + size of this field).
*
* @return the totalSize
*/
public int getTotalSize() {
return totalSize;
}
/**
* Returns flags1 - currently unknown - usually 0x0002.
*
* @return the flags1
*/
public short getFlags1() {
return flags1;
}
/**
* Returns the label field - usually the name of the file (without
* directory) but probably may be any name specified during
* packaging/embedding the data.
*
* @return the label
*/
public String getLabel() {
return label;
}
/**
* Returns the fileName field - usually the name of the file being embedded
* including the full path.
*
* @return the fileName
*/
public String getFileName() {
return fileName;
}
/**
* Returns flags2 - currently unknown - mostly 0x0000.
*
* @return the flags2
*/
public short getFlags2() {
return flags2;
}
/**
* Returns unknown1 field - currently unknown.
*
* @return the unknown1
*/
public short getUnknown1() {
return unknown1;
}
/**
* Returns the command field - usually the name of the file being embedded
* including the full path, may be a command specified during embedding the
* file.
*
* @return the command
*/
public String getCommand() {
return command;
}
/**
* Returns the size of the embedded file. If the size is 0 (zero), no data
* has been embedded. To be sure, that no data has been embedded, check
* whether {@link #getDataBuffer()} returns null.
*
* @return the dataSize
*/
public int getDataSize() {
return dataBuffer.length;
}
/**
* Returns the buffer containing the embedded file's data, or
* null if no data was embedded. Note that an embedding may
* provide information about the data, but the actual data is not included.
* (So label, filename etc. are available, but this method returns
* null.)
*
* @return the dataBuffer
*/
public byte[] getDataBuffer() {
return dataBuffer;
}
/**
* Returns the flags3 - currently unknown.
*
* @return the flags3
*/
public short getFlags3() {
return flags3;
}
/**
* Have the contents printer out into an OutputStream, used when writing a
* file back out to disk (Normally, atom classes will keep their bytes
* around, but non atom classes will just request the bytes from their
* children, then chuck on their header and return)
*/
public void writeOut(OutputStream out) throws IOException {
// byte intbuf[] = new byte[LittleEndianConsts.INT_SIZE];
// byte shortbuf[] = new byte[LittleEndianConsts.SHORT_SIZE];
@SuppressWarnings("resource")
LittleEndianOutputStream leosOut = new LittleEndianOutputStream(out);
switch (mode) {
case parsed: {
ByteArrayOutputStream bos = new ByteArrayOutputStream();
LittleEndianOutputStream leos = new LittleEndianOutputStream(bos);
// total size, will be determined later ..
leos.writeShort(getFlags1());
leos.write(getLabel().getBytes(ISO1));
leos.write(0);
leos.write(getFileName().getBytes(ISO1));
leos.write(0);
leos.writeShort(getFlags2());
leos.writeShort(getUnknown1());
leos.writeInt(getCommand().length() + 1);
leos.write(getCommand().getBytes(ISO1));
leos.write(0);
leos.writeInt(getDataSize());
leos.write(getDataBuffer());
leos.writeShort(getFlags3());
leos.close(); // satisfy compiler ...
leosOut.writeInt(bos.size()); // total size
bos.writeTo(out);
break;
}
case compact:
leosOut.writeInt(getDataSize()+LittleEndianConsts.SHORT_SIZE);
leosOut.writeShort(getFlags1());
out.write(getDataBuffer());
break;
default:
case unparsed:
leosOut.writeInt(getDataSize());
out.write(getDataBuffer());
break;
}
}
public void setFlags1(short flags1) {
this.flags1 = flags1;
}
public void setFlags2(short flags2) {
this.flags2 = flags2;
}
public void setFlags3(short flags3) {
this.flags3 = flags3;
}
public void setLabel(String label) {
this.label = label;
}
public void setFileName(String fileName) {
this.fileName = fileName;
}
public void setCommand(String command) {
this.command = command;
}
public void setUnknown1(short unknown1) {
this.unknown1 = unknown1;
}
public void setDataBuffer(byte dataBuffer[]) {
this.dataBuffer = dataBuffer;
}
}
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