> 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. 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 Bjorsnos has updated the pull request incrementally with three additional commits since the last revision: - A Zip64 extra field used in a LOC header must include both the uncompressed and compressed size fields, and does not include local header offset or disk start number fields. Conequently, a valid LOC Zip64 block must always be 16 bytes long. - Document better the zip command and options used to generate the test vector ZIP - Fix spelling of "presence" ------------- Changes: - all: https://git.openjdk.org/jdk/pull/12524/files - new: https://git.openjdk.org/jdk/pull/12524/files/7601b8dd..a77147bc Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=12524&range=06 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=12524&range=05-06 Stats: 15 lines in 2 files changed: 8 ins; 2 del; 5 mod Patch: https://git.openjdk.org/jdk/pull/12524.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/12524/head:pull/12524 PR: https://git.openjdk.org/jdk/pull/12524
