AndroidXMLDecompress

AndroidXMLDecompress.java

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;

class AndroidXMLDecompress {
	// decompressXML -- Parse the 'compressed' binary form of Android XML docs
	// such as for AndroidManifest.xml in .apk files
	public static int endDocTag = 0x00100101;
	public static int startTag = 0x00100102;
	public static int endTag = 0x00100103;

	static void prt(String str) {
		//System.err.print(str);
	}
	
	public static String decompressXML(byte[] xml) {
		
		StringBuilder finalXML = new StringBuilder();
		
		// Compressed XML file/bytes starts with 24x bytes of data,
		// 9 32 bit words in little endian order (LSB first):
		// 0th word is 03 00 08 00
		// 3rd word SEEMS TO BE: Offset at then of StringTable
		// 4th word is: Number of strings in string table
		// WARNING: Sometime I indiscriminently display or refer to word in
		// little endian storage format, or in integer format (ie MSB first).
		int numbStrings = LEW(xml, 4 * 4);

		// StringIndexTable starts at offset 24x, an array of 32 bit LE offsets
		// of the length/string data in the StringTable.
		int sitOff = 0x24; // Offset of start of StringIndexTable

		// StringTable, each string is represented with a 16 bit little endian
		// character count, followed by that number of 16 bit (LE) (Unicode)
		// chars.
		int stOff = sitOff + numbStrings * 4; // StringTable follows
												// StrIndexTable

		// XMLTags, The XML tag tree starts after some unknown content after the
		// StringTable. There is some unknown data after the StringTable, scan
		// forward from this point to the flag for the start of an XML start
		// tag.
		int xmlTagOff = LEW(xml, 3 * 4); // Start from the offset in the 3rd
											// word.
		// Scan forward until we find the bytes: 0x02011000(x00100102 in normal
		// int)
		for (int ii = xmlTagOff; ii < xml.length - 4; ii += 4) {
			if (LEW(xml, ii) == startTag) {
				xmlTagOff = ii;
				break;
			}
		} // end of hack, scanning for start of first start tag

		// XML tags and attributes:
		// Every XML start and end tag consists of 6 32 bit words:
		// 0th word: 02011000 for startTag and 03011000 for endTag
		// 1st word: a flag?, like 38000000
		// 2nd word: Line of where this tag appeared in the original source file
		// 3rd word: FFFFFFFF ??
		// 4th word: StringIndex of NameSpace name, or FFFFFFFF for default NS
		// 5th word: StringIndex of Element Name
		// (Note: 01011000 in 0th word means end of XML document, endDocTag)

		// Start tags (not end tags) contain 3 more words:
		// 6th word: 14001400 meaning??
		// 7th word: Number of Attributes that follow this tag(follow word 8th)
		// 8th word: 00000000 meaning??

		// Attributes consist of 5 words:
		// 0th word: StringIndex of Attribute Name's Namespace, or FFFFFFFF
		// 1st word: StringIndex of Attribute Name
		// 2nd word: StringIndex of Attribute Value, or FFFFFFF if ResourceId
		// used
		// 3rd word: Flags?
		// 4th word: str ind of attr value again, or ResourceId of value

		// TMP, dump string table to tr for debugging
		// tr.addSelect("strings", null);
		// for (int ii=0; ii<numbStrings; ii++) {
		// // Length of string starts at StringTable plus offset in StrIndTable
		// String str = compXmlString(xml, sitOff, stOff, ii);
		// tr.add(String.valueOf(ii), str);
		// }
		// tr.parent();

		// Step through the XML tree element tags and attributes
		int off = xmlTagOff;
		int indent = 0;
		int startTagLineNo = -2;
		while (off < xml.length) {
			int tag0 = LEW(xml, off);
			// int tag1 = LEW(xml, off+1*4);
			int lineNo = LEW(xml, off + 2 * 4);
			// int tag3 = LEW(xml, off+3*4);
			int nameNsSi = LEW(xml, off + 4 * 4);
			int nameSi = LEW(xml, off + 5 * 4);

			if (tag0 == startTag) { // XML START TAG
				int tag6 = LEW(xml, off + 6 * 4); // Expected to be 14001400
				int numbAttrs = LEW(xml, off + 7 * 4); // Number of Attributes
														// to follow
				// int tag8 = LEW(xml, off+8*4); // Expected to be 00000000
				off += 9 * 4; // Skip over 6+3 words of startTag data
				String name = compXmlString(xml, sitOff, stOff, nameSi);
				// tr.addSelect(name, null);
				startTagLineNo = lineNo;

				// Look for the Attributes
				StringBuffer sb = new StringBuffer();
				for (int ii = 0; ii < numbAttrs; ii++) {
					int attrNameNsSi = LEW(xml, off); // AttrName Namespace Str
														// Ind, or FFFFFFFF
					int attrNameSi = LEW(xml, off + 1 * 4); // AttrName String
															// Index
					int attrValueSi = LEW(xml, off + 2 * 4); // AttrValue Str
																// Ind, or
																// FFFFFFFF
					int attrFlags = LEW(xml, off + 3 * 4);
					int attrResId = LEW(xml, off + 4 * 4); // AttrValue
															// ResourceId or dup
															// AttrValue StrInd
					off += 5 * 4; // Skip over the 5 words of an attribute

					String attrName = compXmlString(xml, sitOff, stOff,
							attrNameSi);
					String attrValue = attrValueSi != -1 ? compXmlString(xml,
							sitOff, stOff, attrValueSi) : "resourceID 0x"
							+ Integer.toHexString(attrResId);
					sb.append(" " + attrName + "=\"" + attrValue + "\"");
					// tr.add(attrName, attrValue);
				}
				finalXML.append("<" + name + sb + ">");
				prtIndent(indent, "<" + name + sb + ">");
				indent++;

			} else if (tag0 == endTag) { // XML END TAG
				indent--;
				off += 6 * 4; // Skip over 6 words of endTag data
				String name = compXmlString(xml, sitOff, stOff, nameSi);
				finalXML.append("</" + name + ">");
				prtIndent(indent, "</" + name + "> (line " + startTagLineNo
						 + "-" + lineNo + ")");
				// tr.parent(); // Step back up the NobTree

			} else if (tag0 == endDocTag) { // END OF XML DOC TAG
				break;

			} else {
				prt("  Unrecognized tag code '" + Integer.toHexString(tag0)
						+ "' at offset " + off);
				break;
			}
		} // end of while loop scanning tags and attributes of XML tree
		//prt("    end at offset " + off);
		return finalXML.toString();
	} // end of decompressXML

	public static String compXmlString(byte[] xml, int sitOff, int stOff, int strInd) {
		if (strInd < 0)
			return null;
		int strOff = stOff + LEW(xml, sitOff + strInd * 4);
		return compXmlStringAt(xml, strOff);
	}

	public static String spaces = "                                             ";

	public static void prtIndent(int indent, String str) {
		prt(spaces.substring(0, Math.min(indent * 2, spaces.length())) + str);
	}

	// compXmlStringAt -- Return the string stored in StringTable format at
	// offset strOff. This offset points to the 16 bit string length, which
	// is followed by that number of 16 bit (Unicode) chars.
	public static String compXmlStringAt(byte[] arr, int strOff) {
		int strLen = arr[strOff + 1] << 8 & 0xff00 | arr[strOff] & 0xff;
		byte[] chars = new byte[strLen];
		for (int ii = 0; ii < strLen; ii++) {
			chars[ii] = arr[strOff + 2 + ii * 2];
		}
		return new String(chars); // Hack, just use 8 byte chars
	} // end of compXmlStringAt

	// LEW -- Return value of a Little Endian 32 bit word from the byte array
	// at offset off.
	public static int LEW(byte[] arr, int off) {
		return arr[off + 3] << 24 & 0xff000000 | arr[off + 2] << 16 & 0xff0000
				| arr[off + 1] << 8 & 0xff00 | arr[off] & 0xFF;
	} // end of LEW
	
	
	
	
	public static void main(String[] args) throws IOException {
		
		String fileName = args[0];
		InputStream is = null;
		ZipFile zip = null;
		
		if (fileName.endsWith(".apk") || fileName.endsWith(".zip")) {
			
			zip = new ZipFile(fileName);
			ZipEntry mft = zip.getEntry("AndroidManifest.xml");
			is = zip.getInputStream(mft);
			
		} else {
			is = new FileInputStream(fileName);
		}
		
		byte[] buf = new byte[10240];
		int bytesRead = is.read(buf);
		
		is.close();
		if (zip != null) {
			zip.close();
		}
		
		String xml = AndroidXMLDecompress.decompressXML(buf);
		
		System.out.println(xml);
	}
}