package com.meituan.android.walle;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.channels.FileChannel;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.UUID;
public final class PayloadWriter {
private PayloadWriter() {
super();
}
/**
* put (id, String) into apk, update if id exists
* @param apkFile apk file
* @param id id
* @param string string content
* @throws IOException
* @throws SignatureNotFoundException
*/
public static void put(final File apkFile, final int id, final String string) throws IOException, SignatureNotFoundException {
put(apkFile, id, string, false);
}
/**
* put (id, String) into apk, update if id exists
* @param apkFile apk file
* @param id id
* @param string string
* @param lowMemory if need low memory operation, maybe a little slower
* @throws IOException
* @throws SignatureNotFoundException
*/
public static void put(final File apkFile, final int id, final String string, final boolean lowMemory) throws IOException, SignatureNotFoundException {
final byte[] bytes = string.getBytes(ApkUtil.DEFAULT_CHARSET);
final ByteBuffer byteBuffer = ByteBuffer.allocate(bytes.length);
byteBuffer.order(ByteOrder.LITTLE_ENDIAN);
byteBuffer.put(bytes, 0, bytes.length);
byteBuffer.flip();
put(apkFile, id, byteBuffer, lowMemory);
}
/**
* put (id, buffer) into apk, update if id exists
*
* @param apkFile apk file
* @param id id
* @param buffer buffer
* @throws IOException
* @throws SignatureNotFoundException
*/
public static void put(final File apkFile, final int id, final ByteBuffer buffer) throws IOException, SignatureNotFoundException {
put(apkFile, id, buffer, false);
}
/**
* put (id, buffer) into apk, update if id exists
* @param apkFile apk file
* @param id id
* @param buffer buffer
* @param lowMemory if need low memory operation, maybe a little slower
* @throws IOException
* @throws SignatureNotFoundException
*/
public static void put(final File apkFile, final int id, final ByteBuffer buffer, final boolean lowMemory) throws IOException, SignatureNotFoundException {
final Map<Integer, ByteBuffer> idValues = new HashMap<Integer, ByteBuffer>();
idValues.put(id, buffer);
putAll(apkFile, idValues, lowMemory);
}
/**
* put new idValues into apk, update if id exists
*
* @param apkFile apk file
* @param idValues id value. NOTE: use unknown IDs. DO NOT use ID that have already been used. See <a href='https://source.android.com/security/apksigning/v2.html'>APK Signature Scheme v2</a>
* @throws IOException
* @throws SignatureNotFoundException
*/
public static void putAll(final File apkFile, final Map<Integer, ByteBuffer> idValues) throws IOException, SignatureNotFoundException {
putAll(apkFile, idValues, false);
}
/**
* put new idValues into apk, update if id exists
*
* @param apkFile apk file
* @param idValues id value. NOTE: use unknown IDs. DO NOT use ID that have already been used. See <a href='https://source.android.com/security/apksigning/v2.html'>APK Signature Scheme v2</a>
* @param lowMemory if need low memory operation, maybe a little slower
* @throws IOException
* @throws SignatureNotFoundException
*/
public static void putAll(final File apkFile, final Map<Integer, ByteBuffer> idValues, final boolean lowMemory) throws IOException, SignatureNotFoundException {
handleApkSigningBlock(apkFile, new ApkSigningBlockHandler() {
@Override
public ApkSigningBlock handle(final Map<Integer, ByteBuffer> originIdValues) {
if (idValues != null && !idValues.isEmpty()) {
originIdValues.putAll(idValues);
}
final ApkSigningBlock apkSigningBlock = new ApkSigningBlock();
final Set<Map.Entry<Integer, ByteBuffer>> entrySet = originIdValues.entrySet();
for (Map.Entry<Integer, ByteBuffer> entry : entrySet) {
final ApkSigningPayload payload = new ApkSigningPayload(entry.getKey(), entry.getValue());
apkSigningBlock.addPayload(payload);
}
return apkSigningBlock;
}
}, lowMemory);
}
/**
* remove content by id
*
* @param apkFile apk file
* @param id id
* @throws IOException
* @throws SignatureNotFoundException
*/
public static void remove(final File apkFile, final int id) throws IOException, SignatureNotFoundException {
remove(apkFile, id, false);
}
/**
* remove content by id
*
* @param apkFile apk file
* @param id id
* @param lowMemory if need low memory operation, maybe a little slower
* @throws IOException
* @throws SignatureNotFoundException
*/
public static void remove(final File apkFile, final int id, final boolean lowMemory) throws IOException, SignatureNotFoundException {
PayloadWriter.handleApkSigningBlock(apkFile, new PayloadWriter.ApkSigningBlockHandler() {
@Override
public ApkSigningBlock handle(final Map<Integer, ByteBuffer> originIdValues) {
final ApkSigningBlock apkSigningBlock = new ApkSigningBlock();
final Set<Map.Entry<Integer, ByteBuffer>> entrySet = originIdValues.entrySet();
for (Map.Entry<Integer, ByteBuffer> entry : entrySet) {
if (entry.getKey() != id) {
final ApkSigningPayload payload = new ApkSigningPayload(entry.getKey(), entry.getValue());
apkSigningBlock.addPayload(payload);
}
}
return apkSigningBlock;
}
}, lowMemory);
}
interface ApkSigningBlockHandler {
ApkSigningBlock handle(Map<Integer, ByteBuffer> originIdValues);
}
static void handleApkSigningBlock(final File apkFile, final ApkSigningBlockHandler handler, final boolean lowMemory) throws IOException, SignatureNotFoundException {
RandomAccessFile fIn = null;
FileChannel fileChannel = null;
try {
fIn = new RandomAccessFile(apkFile, "rw");
fileChannel = fIn.getChannel();
final long commentLength = ApkUtil.getCommentLength(fileChannel);
final long centralDirStartOffset = ApkUtil.findCentralDirStartOffset(fileChannel, commentLength);
// Find the APK Signing Block. The block immediately precedes the Central Directory.
final Pair<ByteBuffer, Long> apkSigningBlockAndOffset = ApkUtil.findApkSigningBlock(fileChannel, centralDirStartOffset);
final ByteBuffer apkSigningBlock2 = apkSigningBlockAndOffset.getFirst();
final long apkSigningBlockOffset = apkSigningBlockAndOffset.getSecond();
final Map<Integer, ByteBuffer> originIdValues = ApkUtil.findIdValues(apkSigningBlock2);
// Find the APK Signature Scheme v2 Block inside the APK Signing Block.
final ByteBuffer apkSignatureSchemeV2Block = originIdValues.get(ApkUtil.APK_SIGNATURE_SCHEME_V2_BLOCK_ID);
if (apkSignatureSchemeV2Block == null) {
throw new IOException(
"No APK Signature Scheme v2 block in APK Signing Block");
}
final boolean needPadding = originIdValues.remove(ApkUtil.VERITY_PADDING_BLOCK_ID) != null;
final ApkSigningBlock apkSigningBlock = handler.handle(originIdValues);
// replace VERITY_PADDING_BLOCK with new one
if (needPadding) {
// uint64: size (excluding this field)
// repeated ID-value pairs:
// uint64: size (excluding this field)
// uint32: ID
// (size - 4) bytes: value
// (extra dummy ID-value for padding to make block size a multiple of 4096 bytes)
// uint64: size (same as the one above)
// uint128: magic
int blocksSize = 0;
for (ApkSigningPayload payload : apkSigningBlock.getPayloads()) {
blocksSize += payload.getTotalSize();
}
int resultSize = 8 + blocksSize + 8 + 16; // size(uint64) + pairs size + size(uint64) + magic(uint128)
if (resultSize % ApkUtil.ANDROID_COMMON_PAGE_ALIGNMENT_BYTES != 0) {
int padding = ApkUtil.ANDROID_COMMON_PAGE_ALIGNMENT_BYTES - 12 // size(uint64) + id(uint32)
- (resultSize % ApkUtil.ANDROID_COMMON_PAGE_ALIGNMENT_BYTES);
if (padding < 0) {
padding += ApkUtil.ANDROID_COMMON_PAGE_ALIGNMENT_BYTES;
}
final ByteBuffer dummy = ByteBuffer.allocate(padding).order(ByteOrder.LITTLE_ENDIAN);
apkSigningBlock.addPayload(new ApkSigningPayload(ApkUtil.VERITY_PADDING_BLOCK_ID,dummy));
}
}
if (apkSigningBlockOffset != 0 && centralDirStartOffset != 0) {
// read CentralDir
fIn.seek(centralDirStartOffset);
byte[] centralDirBytes = null;
File tempCentralBytesFile = null;
// read CentralDir
if (lowMemory) {
tempCentralBytesFile = new File(apkFile.getParent(), UUID.randomUUID().toString());
FileOutputStream outStream = null;
try {
outStream = new FileOutputStream(tempCentralBytesFile);
final byte[] buffer = new byte[1024];
int len;
while ((len = fIn.read(buffer)) > 0){
outStream.write(buffer, 0, len);
}
} finally {
if (outStream != null) {
outStream.close();
}
}
} else {
centralDirBytes = new byte[(int) (fileChannel.size() - centralDirStartOffset)];
fIn.read(centralDirBytes);
}
//update apk sign
fileChannel.position(apkSigningBlockOffset);
final long length = apkSigningBlock.writeApkSigningBlock(fIn);
// update CentralDir
if (lowMemory) {
FileInputStream inputStream = null;
try {
inputStream = new FileInputStream(tempCentralBytesFile);
final byte[] buffer = new byte[1024];
int len;
while ((len = inputStream.read(buffer)) > 0){
fIn.write(buffer, 0, len);
}
} finally {
if (inputStream != null) {
inputStream.close();
}
tempCentralBytesFile.delete();
}
} else {
// store CentralDir
fIn.write(centralDirBytes);
}
// update length
fIn.setLength(fIn.getFilePointer());
// update CentralDir Offset
// End of central directory record (EOCD)
// Offset Bytes Description[23]
// 0 4 End of central directory signature = 0x06054b50
// 4 2 Number of this disk
// 6 2 Disk where central directory starts
// 8 2 Number of central directory records on this disk
// 10 2 Total number of central directory records
// 12 4 Size of central directory (bytes)
// 16 4 Offset of start of central directory, relative to start of archive
// 20 2 Comment length (n)
// 22 n Comment
fIn.seek(fileChannel.size() - commentLength - 6);
// 6 = 2(Comment length) + 4 (Offset of start of central directory, relative to start of archive)
final ByteBuffer temp = ByteBuffer.allocate(4);
temp.order(ByteOrder.LITTLE_ENDIAN);
temp.putInt((int) (centralDirStartOffset + length + 8 - (centralDirStartOffset - apkSigningBlockOffset)));
// 8 = size of block in bytes (excluding this field) (uint64)
temp.flip();
fIn.write(temp.array());
}
} finally {
if (fileChannel != null) {
fileChannel.close();
}
if (fIn != null) {
fIn.close();
}
}
}
}
