zipfile cannot read AES encrypted files

[2561c9ff-0f70-435b-bb88-00745062670a]

BPO	9170
Nosy	@birkenfeld, @amauryfa, @pitrou
Dependencies	bpo-8998: add crypto routines to stdlib
Files	example.zip: Example zip encrypted with WinZip 11.1 using AES 256. Password is "cat".

^{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 = created_at = labels = ['type-feature', 'library'] title = 'zipfile cannot read AES encrypted files' updated_at = user = 'https://bugs.python.org/aymill' ``` bugs.python.org fields: ```python activity = actor = 'georg.brandl' assignee = 'none' closed = True closed_date = closer = 'georg.brandl' components = ['Library (Lib)'] creation = creator = 'aymill' dependencies = ['8998'] files = ['17872'] hgrepos = [] issue_num = 9170 keywords = [] message_count = 4.0 messages = ['109342', '109385', '109650', '199933'] nosy_count = 4.0 nosy_names = ['georg.brandl', 'amaury.forgeotdarc', 'pitrou', 'aymill'] pr_nums = [] priority = 'normal' resolution = 'wont fix' stage = 'needs patch' status = 'closed' superseder = None type = 'enhancement' url = 'https://bugs.python.org/issue9170' versions = ['Python 3.2'] ```

[2561c9ff-0f70-435b-bb88-00745062670a]

On a WinZip AES-256 encrypted zip, zipfile.extractall raises a RuntimeError for "Bad password for file" when given the correct password. Command line example below:

Python 2.6.2 (release26-maint, Apr 19 2009, 01:56:41) 
[GCC 4.3.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from zipfile import ZipFile
>>> zip = ZipFile("example.zip", "r")
>>> zip.extractall(".", pwd="cat")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python2.6/zipfile.py", line 935, in extractall
    self.extract(zipinfo, path, pwd)
  File "/usr/lib/python2.6/zipfile.py", line 923, in extract
    return self._extract_member(member, path, pwd)
  File "/usr/lib/python2.6/zipfile.py", line 963, in _extract_member
    source = self.open(member, pwd=pwd)
  File "/usr/lib/python2.6/zipfile.py", line 898, in open
    raise RuntimeError("Bad password for file", name)
RuntimeError: ('Bad password for file', <zipfile.ZipInfo object at 0xb739e26c>)
>>>

[amauryfa]

zipfile only supports the "Traditional PKWARE Encryption" method. Support for other encryption methods would be useful.

[pitrou]

Do note that providing a patch first requires that encryption/decryption facilities be made available in the stdlib. (right now we only offer hashing, and "high-level" socket wrapping)

[birkenfeld]

bpo-8998 has been closed (among others due to legal concerns), so this need not be kept open.