How to modify git pack files?

Question

I am currently pentesting a git server, and I am trying to figure out how to modify package files. I have my git requests running through a Burp proxy, however I'm not sure how to modify the package files that I see are sent to the git -receive-pack endpoint. Are there any good tools for making simple changes to batch files, such as changing the name and path of the downloaded file?

I found documentation lots in the pack file and for managing them through the git CLI. The problem, however, is that I want to create folder files that have been garbled, which git does not allow. I also found Dulwich , but the docs seem to be small, and I cannot find any examples next to what I want to do.

Any suggestions for modifying these package files would be incredibly helpful.

Answer 1

When it comes to sample packages, you can check out the package-related tests included in Git and see if you can extract your own (failed) packages from them.

For instance:

• t/t5300-pack-object.sh includes package files with dummy arguments, inaccessible objects, and a SHA1 collision,
• t/t5500-fetch-pack.sh enables t/t5500-fetch-pack.sh packages with missing links,
• t/t3210-pack-refs.sh includes the pack-refs.lock file and fixes conflicts
• t/t5400-send-pack.sh enables sending package files that should fail (for example, in denyNonFastForward )