[tahoe-lafs-trac-stream] [Tahoe-LAFS] #3820: Add a session key for immutable uploads

[Tahoe-LAFS]

#3820: Add a session key for immutable uploads
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 Reporter:  itamarst  |          Owner:
     Type:  task      |         Status:  new
 Priority:  normal    |      Milestone:  HTTP Storage Protocol
Component:  unknown   |        Version:  n/a
 Keywords:            |  Launchpad Bug:
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 The current design of the GBS HTTP protocol for uploading buckets
 establishes continuity for the series of writes and/or abort by relying on
 the storage index. Insofar as an untrusted third party knows the storage
 index (perhaps another storage server?), that third party can mess with
 the upload, e.g. abort it half-way.

 This suggests that there is some need for a shared secret tied to each
 individual client->server upload.

 There are two possible high-level approaches:

 1. The server chooses a session key and shares it with client.
 2. The client chooses the session key.

 The second pattern matches existing Tahoe-LAFS interaction patterns, so
 that is what we'll go with as first pass.

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Ticket URL: <https://tahoe-lafs.org/trac/tahoe-lafs/ticket/3820>
Tahoe-LAFS <https://Tahoe-LAFS.org>
secure decentralized storage