pkzip_fmt does not support bzip2 compression type
Nobody has claimed this yet.
- Dominant language
- C
- Stars
- 13.6k
- Forks
- 2.6k
- PR merge metrics
- No merged PRs in 30d
Description
I have a zipfile with bzip2 compressed entries (compression type 'c'). I was initially confused as to why john wasn't accepting my zip2john generated hash as no useful error message was generated. Fortunately, enabling debugging produced a good trail to follow.
I located a file within the zip with a 'stored' compression type and used that file to allow me to continue cracking the password on the zip.
It'd be useful if john-the-ripper could support either the bzip2 compression method, or if zip2john could ignore compression formats not supported by john-the-ripper. The latter would hopefully produce a useful error message if no files were found within the zip with the supported compression format, or choose a file that used a supported compression format if one exists.
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by inspecting the pkzip_fmt handling and the zip2john path for entries using compression type 'c'; reproduce the issue with a ZIP containing bzip2-compressed entries and use the reported debug trail. Done should mean unsupported compression is handled explicitly, either through support or by selecting a supported entry and producing a useful error when none exists.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- c
- Domain
- security
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100