ZipFile does not supports Unicode Path Extra Field (0x7075) zip header field

[0c49011a-ab29-4b67-907b-a43ebd6cc295]

BPO	41928
Nosy	@agiudiceandrea
PRs	python/cpython#23736
Files	23.zip

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields: ```python assignee = None closed_at = None created_at = labels = ['type-feature', 'library', '3.10'] title = 'ZipFile does not supports Unicode Path Extra Field (0x7075) zip header field' updated_at = user = 'https://bugs.python.org/ivansorokintech' ``` bugs.python.org fields: ```python activity = actor = 'andreaerdna' assignee = 'none' closed = False closed_date = None closer = None components = ['Library (Lib)'] creation = creator = 'ivan.sorokin.tech' dependencies = [] files = ['49491'] hgrepos = [] issue_num = 41928 keywords = ['patch'] message_count = 3.0 messages = ['377931', '377945', '385467'] nosy_count = 2.0 nosy_names = ['ivan.sorokin.tech', 'andreaerdna'] pr_nums = ['23736'] priority = 'normal' resolution = None stage = 'patch review' status = 'open' superseder = None type = 'enhancement' url = 'https://bugs.python.org/issue41928' versions = ['Python 3.10'] ```

Linked PRs

• gh-102566

[0c49011a-ab29-4b67-907b-a43ebd6cc295]

See attached sample. Well-known unzip command line tool lists its contents correctly:

$ unzip -l 23.zip
Archive:  23.zip
  Length      Date    Time    Name
---------  ---------- -----   

---

81408  2012-10-23 19:03   Β' ΦΑΣΗ ΠΕ06 ΣΧΟΛΕΙΑ ΕΑΕΠ (ΙΝΤ).xls

--------- ------- 81408 1 file

But ZipFile lists the same file inside this archive as ü' öÇæå Åä06 æòÄèäêÇ äÇäÅ (êîÆ).xls

It's because ZipFile completely ignores Unicode Path Extra Field (0x7075) zip header field.

See .ZIP specification for details on this field meaning and usage: https://pkware.cachefly.net/webdocs/casestudies/APPNOTE.TXT

[0c49011a-ab29-4b67-907b-a43ebd6cc295]

Grand unified algorithm to read filenames from zip files correctly:

1. Do zip entry have «Unicode Path Extra Field» (0x7075)? Use it for file name.
2. Is Unicode flag (0x800) set in «Flags» Field of zip entry? Assume «Filename» Field is in UTF-8.
3. Do «HostOS» Field of zip entry have values of 0 (FAT) or 11 (NTFS)? Assume «Filename» Field is in OEM charset corresponding to system locale.
4. Assume «Filename» Field is in UTF-8.

p7zip with oemcp patch (https://github.com/unxed/oemcp/) uses exactly this method, and is able to process all zip files in my test set correctly (my test set contains several zips generated by different packers on windows, macos, linux, and by online services). The same algorithm should be used in any zip unpacker wishing to process non-latin filenames as gently as possible.

[5da96943-6587-42f9-a33c-9f0eb4f94777]

I submitted more than a month ago a PR that adds support for Unicode Path Extra Field in ZipFile. The PR https://github.com/python/cpython/pull/23736 is awaiting a review in order to be merged.