[1/2] New zip magic

apkzlib/src/main/java/com/android/tools/build/apkzlib/sign/package-info.java

@@ -148,8 +148,8 @@
  * <p>Additionally, by adding/removing extensions we can configure what type of apk we want:
  *
  * <ul>
- *   <li>No SigningExtension ⇒ Aligned, unsigned apk.
+ *   <li>No SigningExtension => Aligned, unsigned apk.
- *   <li>SigningExtension ⇒ Aligned, signed apk.
+ *   <li>SigningExtension => Aligned, signed apk.
  * </ul>
  *
  * So, by configuring which extensions to add, the package task can decide what type of apk we want.

apkzlib/src/main/java/com/android/tools/build/apkzlib/zip/CentralDirectoryHeader.java

@@ -152,6 +152,25 @@ public class CentralDirectoryHeader implements Cloneable {
     file = zFile;
   }
 
+  public CentralDirectoryHeader link(String name, byte[] encodedFileName, GPFlags flags) {
+    var newData = new CentralDirectoryHeader(name,
+      encodedFileName,
+      uncompressedSize,
+      compressInfo,
+      flags,
+      file,
+      lastModTime,
+      lastModDate);
+    newData.extraField = extraField;
+    newData.offset = offset;
+    newData.internalAttributes = internalAttributes;
+    newData.externalAttributes = externalAttributes;
+    newData.comment = comment;
+    newData.madeBy = madeBy;
+    newData.crc32 = crc32;
+    return newData;
+  }
+
   /**
    * Obtains the name of the file.
    *

apkzlib/src/main/java/com/android/tools/build/apkzlib/zip/ExtraField.java

@@ -51,6 +51,9 @@ public class ExtraField {
   /** Header ID for field with zip alignment. */
   static final int ALIGNMENT_ZIP_EXTRA_DATA_FIELD_HEADER_ID = 0xd935;
 
+  /** Header ID for field with linking entry. */
+  static final int LINKING_ENTRY_EXTRA_DATA_FIELD_HEADER_ID = 0x2333;
+
   /**
    * The field's raw data, if it is known. Either this variable or {@link #segments} must be
    * non-{@code null}.
@@ -382,4 +385,43 @@ public class ExtraField {
       return ALIGNMENT_ZIP_EXTRA_DATA_FIELD_HEADER_ID;
     }
   }
+
+  public static class LinkingEntrySegment implements Segment {
+
+    private final StoredEntry linkingEntry;
+    private int dataOffset = 0;
+    private long zipOffset = 0;
+
+    public LinkingEntrySegment(StoredEntry linkingEntry) throws IOException {
+      Preconditions.checkArgument(linkingEntry.isLinkingEntry(), "linkingEntry is not a linking entry");
+      this.linkingEntry = linkingEntry;
+    }
+
+    @Override
+    public int getHeaderId() {
+      return LINKING_ENTRY_EXTRA_DATA_FIELD_HEADER_ID;
+    }
+
+    @Override
+    public int size() {
+      return linkingEntry.getLocalHeaderSize() + 4;
+    }
+
+    public void setOffset(int dataOffset, long zipOffset) {
+      this.dataOffset = dataOffset;
+      this.zipOffset = zipOffset;
+    }
+
+    @Override
+    public void write(ByteBuffer out) throws IOException {
+      if (dataOffset == 0 || zipOffset == 0) {
+        throw new IOException("linking entry has 0 offset");
+      }
+      LittleEndianUtils.writeUnsigned2Le(out, LINKING_ENTRY_EXTRA_DATA_FIELD_HEADER_ID);
+      LittleEndianUtils.writeUnsigned2Le(out, linkingEntry.getLocalHeaderSize());
+      var offset = out.position();
+      linkingEntry.writeData(out, dataOffset - linkingEntry.getLocalHeaderSize() - offset);
+      linkingEntry.replaceSourceFromZip(offset + zipOffset);
+    }
+  }
 }

apkzlib/src/main/java/com/android/tools/build/apkzlib/zip/StoredEntry.java

@@ -25,6 +25,7 @@ import com.google.common.base.Preconditions;
 import com.google.common.base.Supplier;
 import com.google.common.base.Suppliers;
 import com.google.common.base.Verify;
+import com.google.common.collect.ImmutableList;
 import com.google.common.io.ByteStreams;
 import com.google.common.primitives.Ints;
 import java.io.BufferedInputStream;
@@ -154,6 +155,12 @@ public class StoredEntry {
   /** Storage used to create buffers when loading storage into memory. */
   private final ByteStorage storage;
 
+  /** Entry it is linking to. */
+  private final StoredEntry linkedEntry;
+
+  /** Offset of the nested link */
+  private final int nestedLinkOffset = 0;
+
   /**
    * Creates a new stored entry.
    *
@@ -170,11 +177,37 @@ public class StoredEntry {
           @Nullable ProcessedAndRawByteSources source,
           ByteStorage storage)
           throws IOException {
+      this(header, file, source, storage, null);
+  }
+
+  StoredEntry(
+          String name,
+          ZFile file,
+          ByteStorage storage,
+          StoredEntry linkedEntry)
+          throws IOException {
+    this(linkedEntry.linkingCentralDirectoryHeader(name), file, linkedEntry.getSource(), storage, linkedEntry);
+  }
+
+  private CentralDirectoryHeader linkingCentralDirectoryHeader(String name) {
+    boolean encodeWithUtf8 = !EncodeUtils.canAsciiEncode(name);
+    GPFlags flags = GPFlags.make(encodeWithUtf8);
+    return cdh.link(name, EncodeUtils.encode(name, flags), flags);
+  }
+
+  StoredEntry(
+      CentralDirectoryHeader header,
+      ZFile file,
+      @Nullable ProcessedAndRawByteSources source,
+      ByteStorage storage,
+      StoredEntry linkedEntry)
+      throws IOException {
     cdh = header;
     this.file = file;
     deleted = false;
     verifyLog = file.makeVerifyLog();
     this.storage = storage;
+    this.linkedEntry = linkedEntry;
 
     if (header.getOffset() >= 0) {
       readLocalHeader();
@@ -579,6 +612,7 @@ public class StoredEntry {
     ProcessedAndRawByteSources oldSource = source;
     source = createSourceFromZip(zipFileOffset);
     cdh.setOffset(zipFileOffset);
+    if (!isLinkingEntry())
       oldSource.close();
   }
 
@@ -667,6 +701,11 @@ public class StoredEntry {
   }
 
   private void writeData(ByteBuffer out) throws IOException {
+    writeData(out, 0);
+  }
+
+  void writeData(ByteBuffer out, int extraOffset) throws IOException {
+    Preconditions.checkArgument(extraOffset >= 0 , "extraOffset < 0");
     CentralDirectoryHeaderCompressInfo compressInfo = cdh.getCompressionInfoWithWait();
 
     F_LOCAL_SIGNATURE.write(out);
@@ -686,7 +725,7 @@ public class StoredEntry {
     F_COMPRESSED_SIZE.write(out, compressInfo.getCompressedSize());
     F_UNCOMPRESSED_SIZE.write(out, cdh.getUncompressedSize());
     F_FILE_NAME_LENGTH.write(out, cdh.getEncodedFileName().length);
-    F_EXTRA_LENGTH.write(out, localExtra.size());
+    F_EXTRA_LENGTH.write(out, localExtra.size() + extraOffset);
 
     out.put(cdh.getEncodedFileName());
     localExtra.write(out);
@@ -706,9 +745,15 @@ public class StoredEntry {
   public boolean realign() throws IOException {
     Preconditions.checkState(!deleted, "Entry has been deleted.");
 
+    if (isLinkingEntry()) return true;
+
     return file.realign(this);
   }
 
+  public boolean isLinkingEntry() {
+    return linkedEntry != null;
+  }
+
   /**
    * Obtains the contents of the local extra field.
    *

apkzlib/src/main/java/com/android/tools/build/apkzlib/zip/ZFile.java

@@ -284,6 +284,11 @@ public class ZFile implements Closeable {
    */
   private final List<StoredEntry> uncompressedEntries;
 
+  /** LSPatch
+   *
+   */
+  private final List<StoredEntry> linkingEntries;
+
   /** Current state of the zip file. */
   private ZipFileState state;
 
@@ -449,6 +454,7 @@ public class ZFile implements Closeable {
 
     entries = Maps.newHashMap();
     uncompressedEntries = Lists.newArrayList();
+    linkingEntries = Lists.newArrayList();
     extraDirectoryOffset = 0;
 
     try {
@@ -580,6 +586,10 @@ public class ZFile implements Closeable {
       entries.put(uncompressed.getCentralDirectoryHeader().getName(), uncompressed);
     }
 
+    for (StoredEntry linking: linkingEntries) {
+      entries.put(linking.getCentralDirectoryHeader().getName(), linking);
+    }
+
     return Sets.newHashSet(entries.values());
   }
 
@@ -1398,7 +1408,15 @@ public class ZFile implements Closeable {
 
     int r;
     // Put header data to the beginning of buffer
+    // LSPatch: write extra entries in the extra field if it's a linking
+    int localHeaderSize = entry.getLocalHeaderSize();
+    for (var segment : entry.getLocalExtra().getSegments()) {
+      if (segment instanceof ExtraField.LinkingEntrySegment) {
+        ((ExtraField.LinkingEntrySegment) segment).setOffset(localHeaderSize, offset);
+      }
+    }
     int readOffset = entry.toHeaderData(chunk);
+    assert localHeaderSize == readOffset;
     long writeOffset = offset;
     try (InputStream is = entry.getSource().getRawByteSource().openStream()) {
       while ((r = is.read(chunk, readOffset, chunk.length - readOffset)) >= 0 || readOffset > 0) {
@@ -1433,6 +1451,8 @@ public class ZFile implements Closeable {
       newStored.add(mapEntry.getStore());
     }
 
+    newStored.addAll(linkingEntries);
+
     /*
      * Make sure we truncate the map before computing the central directory's location since
      * the central directory is the last part of the file.
@@ -1527,7 +1547,7 @@ public class ZFile implements Closeable {
 
       dirStart = directoryEntry.getStart();
       dirSize = directoryEntry.getSize();
-      Verify.verify(directory.getEntries().size() == entries.size());
+      Verify.verify(directory.getEntries().size() == entries.size() + linkingEntries.size());
     } else {
       /*
        * If we do not have a directory, then we must leave any requested offset empty.
@@ -1707,8 +1727,8 @@ public class ZFile implements Closeable {
    * @throws IOException failed to read the source data
    * @throws IllegalStateException if the file is in read-only mode
    */
-  public void add(String name, InputStream stream, boolean mayCompress) throws IOException {
+  public StoredEntry add(String name, InputStream stream, boolean mayCompress) throws IOException {
-    add(name, storage.fromStream(stream), mayCompress);
+    return add(name, storage.fromStream(stream), mayCompress);
   }
 
   /**
@@ -1735,7 +1755,7 @@ public class ZFile implements Closeable {
     add(name, new CloseableDelegateByteSource(source, sizeBytes.get()), mayCompress);
   }
 
-  private void add(String name, CloseableByteSource source, boolean mayCompress)
+  private StoredEntry add(String name, CloseableByteSource source, boolean mayCompress)
       throws IOException {
     checkNotInReadOnlyMode();
 
@@ -1744,9 +1764,25 @@ public class ZFile implements Closeable {
      */
     processAllReadyEntries();
 
-    add(makeStoredEntry(name, source, mayCompress));
+    return add(makeStoredEntry(name, source, mayCompress));
   }
 
+  public void addLink(String name, StoredEntry linkedEntry)
+          throws CloneNotSupportedException,IOException {
+    Preconditions.checkArgument(linkedEntry != null, "linkedEntry is null");
+    Preconditions.checkArgument(linkedEntry.getCentralDirectoryHeader().getOffset() < 0, "linkedEntry is not new file");
+    Preconditions.checkArgument(!linkedEntry.isLinkingEntry(), "linkedEntry is a linking entry");
+    var linkingEntry = new StoredEntry(name, this, storage, linkedEntry);
+    linkingEntries.add(linkingEntry);
+    linkedEntry.setLocalExtraNoNotify(new ExtraField(ImmutableList.<ExtraField.Segment>builder().add(linkedEntry.getLocalExtra().getSegments().toArray(new ExtraField.Segment[0])).add(new ExtraField.LinkingEntrySegment(linkingEntry)).build()));
+  }
+
+  public void addNestedZipWithLinks(Map<String, String> nameMapping)
+          throws CloneNotSupportedException,IOException {
+    // TODO: nested link
+  }
+
+
   /**
    * Adds a {@link StoredEntry} to the zip. The entry is not immediately added to {@link #entries}
    * because data may not yet be available. Instead, it is placed under {@link #uncompressedEntries}
@@ -1760,9 +1796,10 @@ public class ZFile implements Closeable {
    * @throws IOException failed to process this entry (or a previous one whose future only completed
    *     now)
    */
-  private void add(final StoredEntry newEntry) throws IOException {
+  private StoredEntry add(final StoredEntry newEntry) throws IOException {
     uncompressedEntries.add(newEntry);
     processAllReadyEntries();
+    return newEntry;
   }
 
   /**

patch/src/main/java/org/lsposed/patch/LSPatch.java

@@ -225,7 +225,8 @@ public class LSPatch {
             for (String arch : APK_LIB_PATH_ARRAY) {
                 String entryName = "assets/lib/lspd/" + arch + "/liblspd.so";
                 try (var is = getClass().getClassLoader().getResourceAsStream("assets/so/" + (arch.equals("arm") ? "armeabi-v7a" : (arch.equals("arm64") ? "arm64-v8a" : arch)) + "/liblspd.so")) {
-                    dstZFile.add(entryName, is, false); // no compress for so
+                    var entry = dstZFile.add(entryName, is, false); // no compress for so
+                    dstZFile.addLink("assets/lib/lspd/test/" + arch + "/liblspd.so", entry);
                 } catch (Throwable e) {
                     // More exception info
                     throw new PatchError("Error when adding native lib", e);