[tahoe-dev] [tahoe-lafs] #684: let client specify the encryption key

[Zooko Wilcox-O'Hearn]

On May 24, 2009, at 14:48 PM, Shawn Willden wrote:

> I need a way to map content hashes to read caps, because my backup  
> log contains content hashes.  I can't put read caps in the backup  
> log for a couple of reasons which should become clear below.

They did not become clear to me.  Why can't you put read caps in the  
backup log?  I guess in general you don't want to do that unless, of  
course, you want someone having access to the backup log itself to  
give them access to all the files.  Do you want that?

Something we generally do is, if we *don't* want that, then we use  
the verify cap instead.  For example the 'recent uploads and  
downloads' page in the WUI shows the verifycaps of each file or  
directory.  Would it make sense to use verify caps in your backup log?

(One potential problem is that it is more expensive to compute verify  
caps than to compute a flat hash of the plaintext of the file.)

Regards,

Zooko