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@seymores
Created May 24, 2011 07:19
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AndroidManifest.xml decompressor
// decompressXML -- Parse the 'compressed' binary form of Android XML docs
// such as for AndroidManifest.xml in .apk files
int endDocTag = 0x00100101;
int startTag = 0x00100102;
int endTag = 0x00100103;
public void decompressXML(byte[] xml) {
// 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) == 0x00100102) {
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 == 0x00100102) { // 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);
}
prtIndent(indent, "<"+name+sb+">");
indent++;
} else if (tag0 == 0x00100103) { // XML END TAG
indent--;
off += 6*4; // Skip over 6 words of endTag data
String name = compXmlString(xml, sitOff, stOff, nameSi);
prtIndent(indent, "</"+name+"> (line "+startTagLineNo+"-"+lineNo+")");
//tr.parent(); // Step back up the NobTree
} else if (tag0 == 0x00100101) { // 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);
} // end of decompressXML
public 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);
}
String spaces = " ";
public void prtIndent(int indent, String str) {
String spaces = " ";
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 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 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
def prt(output) { println output }
def file = new File("AndroidManifest.xml")
decompressXML file.bytes
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