** Branch linked: lp:~mandel/ubuntu-download-manager/check-hash -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to click in Ubuntu. https://bugs.launchpad.net/bugs/1330770
Title: click packages rely upon tls for integrity and authenticity Status in the base for Ubuntu mobile products: Confirmed Status in Click Package metadata search service: Fix Released Status in Online service used by software center: Fix Released Status in click package in Ubuntu: Fix Released Status in ubuntu-system-settings package in Ubuntu: Confirmed Status in unity-scope-click package in Ubuntu: Fix Released Status in ubuntu-system-settings package in Ubuntu RTM: Confirmed Bug description: Hello, I just completed a quick review of the click source and the unity-scope-click source and behaviours, and found some opportunities for improvement. Debian, and Ubuntu, rely upon signed repository files with cryptographic hashes of packages to provide both integrity and authenticity checks for the packages hosted on that repository. The click framework and the unity-scope-click discovery and installation tool do not use signed repository files, nor do they have signatures of any sort on downloaded packages. The only integrity and authenticity checks are provided by the use of HTTPS. The click verify command will check files within the archive against MD5sums stored inside the archive but the click verify command is not used during package installation. (This is suitable for validating integrity against accidental changes only.) While it appears that unity-scope-click properly uses HTTPS to download package metadata and packages, HTTPS alone is insufficient for our needs: - Someone in a position to create new certificates at any of several hundred certificate authorities could create certificates purporting to be our update servers. This actual problem has been discovered in the wild with several certificate authorities issuing wild-card certificates or even certificates with signing authority. - X.509 is extremely complicated; TLS is extremely complicated. Flaws in both are inevitable. - HTTPS prevents the use of caching. - HTTPS only 'works' for data-in-motion; it is useless for data-at- rest integrity and authenticity checks. I have not yet reviewed the tools that application authors will use to upload their packages to our distribution servers but note in passing that most of these issues are also issues for adding packages to our update servers -- packages in flight within our network can be corrupted for many reasons, packages on disk can be corrupted for many reasons. A signature mechanism can protect against internal network faults, storage faults, and provide assurance months or years later that an uploaded package was uploaded by someone in control of a corresponding private key. Thanks To manage notifications about this bug go to: https://bugs.launchpad.net/canonical-devices-system-image/+bug/1330770/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
