diff options
| -rw-r--r-- | core/java/android/util/apk/ApkVerityBuilder.java | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/core/java/android/util/apk/ApkVerityBuilder.java b/core/java/android/util/apk/ApkVerityBuilder.java index 4c6e511ede46..a3eeb275064a 100644 --- a/core/java/android/util/apk/ApkVerityBuilder.java +++ b/core/java/android/util/apk/ApkVerityBuilder.java @@ -106,18 +106,22 @@ abstract class ApkVerityBuilder { calculateFsveritySignatureInternal(apk, signatureInfo, null, null, header, extensions); MessageDigest md = MessageDigest.getInstance(JCA_DIGEST_ALGORITHM); - md.update(DEFAULT_SALT); - md.update(verityBlock); + md.update(header); + md.update(extensions); md.update(apkDigest); return md.digest(); } + /** + * Internal method to generate various parts of FSVerity constructs, including the header, + * extensions, Merkle tree, and the tree's root hash. The output buffer is flipped to the + * generated data size and is readey for consuming. + */ private static void calculateFsveritySignatureInternal( RandomAccessFile apk, SignatureInfo signatureInfo, ByteBuffer treeOutput, ByteBuffer rootHashOutput, ByteBuffer headerOutput, ByteBuffer extensionsOutput) throws IOException, NoSuchAlgorithmException, DigestException { assertSigningBlockAlignedAndHasFullPages(signatureInfo); - long signingBlockSize = signatureInfo.centralDirOffset - signatureInfo.apkSigningBlockOffset; long dataSize = apk.length() - signingBlockSize - ZIP_EOCD_CENTRAL_DIR_OFFSET_FIELD_SIZE; @@ -128,6 +132,7 @@ abstract class ApkVerityBuilder { levelOffset, treeOutput); if (rootHashOutput != null) { rootHashOutput.put(apkRootHash); + rootHashOutput.flip(); } } @@ -333,9 +338,9 @@ abstract class ApkVerityBuilder { buffer.put((byte) 0); // auth block offset, disabled here buffer.put((byte) 2); // extension count buffer.put(salt); // salt (8 bytes) - // skip(buffer, 22); // reserved + skip(buffer, 22); // reserved - buffer.rewind(); + buffer.flip(); return buffer; } @@ -396,12 +401,10 @@ abstract class ApkVerityBuilder { buffer.put((byte) ZIP_EOCD_CENTRAL_DIR_OFFSET_FIELD_SIZE); // length skip(buffer, 7); // reserved buffer.putInt(Math.toIntExact(signingBlockOffset)); // databytes - - // There are extra kPadding bytes of 0s here, included in the total size field of the - // extension header. The output ByteBuffer is assumed to be initialized to 0. + skip(buffer, kPadding); // padding } - buffer.rewind(); + buffer.flip(); return buffer; } |