On Wed, 10 Jan 2024 13:39:52 GMT, Eirik Bjørsnøs <eir...@openjdk.org> wrote:
>> ZipInputStream.readEnd currently assumes a Zip64 data descriptor if the >> number of compressed or uncompressed bytes read from the inflater is larger >> than the Zip64 magic value. >> >> While the ZIP format mandates that the data descriptor `SHOULD be stored in >> ZIP64 format (as 8 byte values) when a file's size exceeds 0xFFFFFFFF`, it >> also states that `ZIP64 format MAY be used regardless of the size of a >> file`. For such small entries, the above assumption does not hold. >> >> This PR augments ZipInputStream.readEnd to also assume 8-byte sizes if the >> ZipEntry includes a Zip64 extra information field AND the 'compressed size' >> and 'uncompressed size' have the expected Zip64 "magic" value 0xFFFFFFFF. >> This brings ZipInputStream into alignment with the APPNOTE format spec: >> >> >> When extracting, if the zip64 extended information extra >> field is present for the file the compressed and >> uncompressed sizes will be 8 byte values. >> >> >> While small Zip64 files with 8-byte data descriptors are not commonly found >> in the wild, it is possible to create one using the Info-ZIP command line >> `-fd` flag: >> >> `echo hello | zip -fd > hello.zip` >> >> The PR also adds a test verifying that such a small Zip64 file can be parsed >> by ZipInputStream. > > Eirik Bjørsnøs has updated the pull request incrementally with two additional > commits since the last revision: > > - Remove trailing whitespace > - Remove trailing whitespace src/java.base/share/classes/java/util/zip/ZipInputStream.java line 657: > 655: * @param size the value of the 'uncompressed size' field in the LOC > 656: */ > 657: private boolean expect64BitDataDescriptor(byte[] extra, int flag, > long csize, long size) { Suggestion: private boolean expect64BitDataDescriptor(byte[] extra, int flag, long csize, long size) { test/jdk/java/util/zip/ZipInputStream/Zip64DataDescriptor.java line 113: > 111: // This ZIP has the regular 4-bit data descriptor > 112: > 113: byte[] extra = new byte[Long.BYTES + Long.BYTES + Short.BYTES * > 2]; // Size of a regular Zip64 extra field Suggestion: byte[] extra = new byte[Long.BYTES + Long.BYTES + Short.BYTES * 2]; // Size of a regular Zip64 extra field ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/12524#discussion_r1452996737 PR Review Comment: https://git.openjdk.org/jdk/pull/12524#discussion_r1452996515