After repeatedly suffering issues with scam apps making it onto the Snap Store, Canonical maker of Ubuntu Linux have now decided to manually look over submissions.
Oh my. That’s extremely disappointing. I love the project but part of making software free and accessible is ensuring that trust is reasonable to place in it. I’ll probably still see if I can get my head around dpkg enough to fork it to replace MD5 with an actually secure hashing algorithm and make signing mandatory. I’ve found what I think is the file specification already (my C is in need of exercising) and I’ve been waiting too long for my with to get back to me on contributing to open source projects so, this could be a good one.
Please do share the white paper when published. I’m looking forward to that.
I admire your gusto! I think it’s doable, and you can definitely pull it off if you want to. To replace MD5 and implement signatures you need to do the following, as a high level overview:
Extend dpkg to know what SHA2 is, and reliably detect it. (maybe measure hash length or specifying a new version using the control file?)
dpkg must also know what a signature is. More on that below.
Providing automatic/mandatory signing will require code to handle PKI as well as a place to store the signing information. I would do it by signing the two archives found within Deb packages, then placing information about the signing in the top-level of the package. Existing tools need to be able to ignore or handle whatever you implement as a rule of thumb.
Note that this is just my approach and maybe you can do better.
I also recommended looking into https://lists.debian.org/debian-dpkg/2001/03/msg00024.html. This is the thread I mentioned earlier, in which package signatures were discussed and ultimately turned down. Maybe the easiest approach is to re-implement what the contributor was trying to do back then, but with modern code and standards? If you want more resources, including my presentation on the topic to HackCFL and CitrusSec, let me know. I am here for whatever technical assistance or industry contacts I can provide. The white paper might be done in a month, minus peer review. I’m very busy and so is he. Good luck in any case!
Oh my. That’s extremely disappointing. I love the project but part of making software free and accessible is ensuring that trust is reasonable to place in it. I’ll probably still see if I can get my head around dpkg enough to fork it to replace MD5 with an actually secure hashing algorithm and make signing mandatory. I’ve found what I think is the file specification already (my C is in need of exercising) and I’ve been waiting too long for my with to get back to me on contributing to open source projects so, this could be a good one.
Please do share the white paper when published. I’m looking forward to that.
I admire your gusto! I think it’s doable, and you can definitely pull it off if you want to. To replace MD5 and implement signatures you need to do the following, as a high level overview:
Extend dpkg to know what SHA2 is, and reliably detect it. (maybe measure hash length or specifying a new version using the control file?)
dpkg must also know what a signature is. More on that below.
Providing automatic/mandatory signing will require code to handle PKI as well as a place to store the signing information. I would do it by signing the two archives found within Deb packages, then placing information about the signing in the top-level of the package. Existing tools need to be able to ignore or handle whatever you implement as a rule of thumb.
Note that this is just my approach and maybe you can do better.
I also recommended looking into https://lists.debian.org/debian-dpkg/2001/03/msg00024.html. This is the thread I mentioned earlier, in which package signatures were discussed and ultimately turned down. Maybe the easiest approach is to re-implement what the contributor was trying to do back then, but with modern code and standards? If you want more resources, including my presentation on the topic to HackCFL and CitrusSec, let me know. I am here for whatever technical assistance or industry contacts I can provide. The white paper might be done in a month, minus peer review. I’m very busy and so is he. Good luck in any case!