[tor-bugs] #30428 [Core Tor/Tor]: sendme: Failure to validate authenticated SENDMEs client side

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#30428: sendme: Failure to validate authenticated SENDMEs client side
-------------------------------------------------+-------------------------
 Reporter:  dgoulet                              |          Owner:  dgoulet
     Type:  defect                               |         Status:
                                                 |  needs_review
 Priority:  Very High                            |      Milestone:  Tor:
                                                 |  0.4.1.x-final
Component:  Core Tor/Tor                         |        Version:
 Severity:  Normal                               |     Resolution:
 Keywords:  tor-circuit, sendme, 041-must,       |  Actual Points:
  0411-alpha, postfreeze-ok                      |
Parent ID:  #26288                               |         Points:  1
 Reviewer:  nickm                                |        Sponsor:
                                                 |  SponsorV
-------------------------------------------------+-------------------------
Changes (by dgoulet):

 * status:  merge_ready => needs_review


Comment:

 Replying to [comment:12 nickm]:
 > Looks good; how are the tests looking?

 The new very small commit `4ef8470fa5480d3b` actually broke things when I
 tested with the latest chutney `bidi` branch.

 Turns out that we needed that `minus 1` on the window. I explain why in
 the new commit. I've thus reverted `4ef8470fa5480d3b` as well first and
 then new commit:

 {{{
 19c086365957dc93
   sendme: Clarify how sendme_circuit_cell_is_next() works [David Goulet]
 6380a2f307ba8f7b
   Revert "sendme: Off by one on the SENDME window" [David Goulet]
 }}}

 This has been quite tested now just to find that issue that was not
 showing up reliably for unknown reasons on nickm's `bidi` chutney.

 I confirm that the digests matches as expected on both sides.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/30428#comment:13>
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