[tor-bugs] #32830 [Core Tor]: Relay_extended - hash and padding - specs are wrong or unclear

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#32830: Relay_extended - hash and padding - specs are wrong or unclear
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 Reporter:  Aymeric   |          Owner:  (none)
     Type:  defect    |         Status:  new
 Priority:  Medium    |      Milestone:
Component:  Core Tor  |        Version:
 Severity:  Normal    |     Resolution:
 Keywords:            |  Actual Points:
Parent ID:            |         Points:
 Reviewer:            |        Sponsor:
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Comment (by Aymeric):

 Maybe it's me because rereading it I find it clear now but I
 misinterpreted "cell's entire payload" with "stream payload"

 So, maybe, it does not harm to add something like:

 "the 'digest' field is computed as the first four bytes of the running
 digest of all the bytes that have been destined for this hop of the
 circuit or originated from this hop of the circuit, seeded from Df or Db
 respectively (obtained in section 5.2 above), and including this RELAY
 cell's entire payload (including padding bytes and taken with the digest
 field set to zero)."

 Why is there this 4 zero bytes separator before padding bytes? (is it
 somewhere in the specs?)

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/32830#comment:3>
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