* Michael Richardson <m...@sandelman.ca> [24.02.2017 19:00]: [...]
> The server can either given everyone during a period of an hour the same > random challenge, it can make them up and store them, or it can construct > them as the HMAC-SHA256 of, for instance, the IP address which is asking, > such that it never has to record any of them. > > A script kiddie now needs to do some work each time, has to request a new > token each time, and if the challenges are based upon IP address, the kiddie > can vote once per IP address they have. So, now they need a bot net to > vote a lot... probably that's okay. thank you for this very good explanation. > >> I thought from the subject line and explanation that it was to permit > >> a firmware image to be validated as being uncorrupted/tained. One > >> might do this before flashing a device with it. > > > how should this be done before flashing? if there is a mistake > > (e.g. forgotten package during build) the image itself is fine, but not > > "good". > > Right. So getting the stamp into the image at the very last moment is the > key. That way the build is reproduceable if you ignore those very few bytes. > Ideally, there is a spot in the image that shows up to userspace. Have you > figured this part out? I would attempt to make it a kernel boot command > line option, if that can be tweaked easily. for now i patch 'usign' for a now option B = build: root@LEDE:~ :) usign -B 98021604736550012081493806018992642304441039324849310980174888200312941028157 114543661949658574850110716953530268394806126479026079327889534650057251922973 (it output the 2 prime factors for the solution) baking it into the kernel-commandline is an interesting idea: we have already figured out how to do this for each target, because we are baking a special thing in out kernel: root@LEDE:~ :) cat /proc/cmdline board=TL-WR1043ND oops=panic panic=10 console=ttyS0,115200 rootfstype=squashfs,jffs2 noinitrd ^^^^^^^^^^^^^^^^^^^ prevent seldom hangs during boot... so we can easily add: prime1=x prime2=y or secret=foo thanks a lot for your input, i will think about it and implement your ideas. bye, bastian _______________________________________________ Lede-dev mailing list Lede-dev@lists.infradead.org http://lists.infradead.org/mailman/listinfo/lede-dev