RFR: 8303866: Allow ZipInputStream.readEnd to parse small Zip64 ZIP files [v16]

[Jaikiran Pai]

On Mon, 5 Feb 2024 13:14:39 GMT, Eirik Bjørsnøs <eirbjo at 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 at least one of 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 with a new target base due to a merge or a rebase. The pull request now contains 230 commits:
> 
>  - Update readZipInputStream to verify that the ZipInputStream finds a single zip entry with the expected contents
>  - Merge branch 'master' into data-descriptor
>  - Merge branch 'master' into data-descriptor
>  - Update comment of expect64BitDataDescriptor to reflect relaxed validation
>  - Dial down validation of the Zip64 extra field
>  - 8321712: C2: "failed: Multiple uses of register" in C2_MacroAssembler::vminmax_fp
>    
>    Co-authored-by: Volodymyr Paprotski <vpaprotski at openjdk.org>
>    Reviewed-by: kvn, thartmann, epeter, jbhateja
>  - 8319128: sun/security/pkcs11 tests fail on OL 7.9 aarch64
>    
>    Reviewed-by: mbaesken
>  - 8322971: KEM.getInstance() should check if a 3rd-party security provider is signed
>    
>    Reviewed-by: mullan, valeriep
>  - 8320890: [AIX] Find a better way to mimic dl handle equality
>    
>    Reviewed-by: stuefe, mdoerr
>  - 8323276: StressDirListings.java fails on AIX
>    
>    Reviewed-by: jpai, dfuchs
>  - ... and 220 more: https://git.openjdk.org/jdk/compare/692c9f88...e8d3b904

Thank you for the update, looks good to me.

-------------

Marked as reviewed by jpai (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/12524#pullrequestreview-1862767326