Commit 7b1a76c7 authored by Dave Rolek's avatar Dave Rolek
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Update spec with SHOULD/MUST behavior for padding bytes 

In doing so, specify a general behavior for padding bytes in Section 3
and cross-reference other locations to this, to aid in future
consistency.

Also clarify a few vague parts of the prior wording.

Fixes #26860.
parent 1fb4cb58

tor-spec.txt

+6 −2
Original line number Diff line number Diff line
@@ -477,7 +477,9 @@ see tor-design.pdf. 
   drop the cell.  Since more cell types may be added in the future, ORs

   should generally not warn when encountering unrecognized commands.



   The payload is padded with 0 bytes.

   The cell is padded up to the cell length with padding bytes. Senders

   SHOULD set padding bytes to NUL and receivers MUST ignore their

   value.



   PADDING cells are currently used to implement connection keepalive.

   If there is no other traffic, ORs and OPs send one another a PADDING
@@ -1479,7 +1481,9 @@ see tor-design.pdf. 


   The 'Length' field of a relay cell contains the number of bytes in

   the relay payload which contain real payload data. The remainder of

   the payload is padded with NUL bytes.

   the unencrypted payload is padded with padding bytes. Implementations

   handle padding bytes of unencrypted relay cells as they do padding

   bytes for other cell types; see Section 3.



   If the RELAY cell is recognized but the relay command is not

   understood, the cell must be dropped and ignored. Its contents