[tahoe-dev] [tahoe-lafs] #833: reject mutable children when *reading* an immutable dirnode

[tahoe-lafs]

#833: reject mutable children when *reading* an immutable dirnode
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 Reporter:  warner         |           Owner:  warner  
     Type:  defect         |          Status:  assigned
 Priority:  critical       |       Milestone:  1.6.0   
Component:  code-dirnodes  |         Version:  1.5.0   
 Keywords:  integrity      |   Launchpad_bug:          
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Comment(by warner):

 I guess it comes down to how we deal with caps-from-the-future. We can't
 distinguish between mutable-caps-from-the-future and immutable-caps-from-
 the-future, since we can't figure out anything about caps-from-the-future
 other than the fact that we don't understand them. So if we want to
 promise users who are listing an immutable directory that they'll only see
 immutable caps, we'd have to filter out anything that we don't explicitly
 recognize as immutable, which means removing all caps-from-the-future.

 This would mean that "tahoe ls" couldn't even acknowledge the existence of
 such caps. Older clients would be more likely to overwrite them if they
 can't see them at all. And it limits the ability of other tools (perhaps
 smarter or more up-to-date than the tahoe node they're using) to do
 something with those caps.

 I dunno what's the best thing to do. I agree that it feels a bit leaky,
 but I'm also uncomfortable with censoring out the existence of caps-from-
 the-future.

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Ticket URL: <http://allmydata.org/trac/tahoe/ticket/833#comment:7>
tahoe-lafs <http://allmydata.org>
secure decentralized file storage grid