[tor-commits] [torspec/master] Better description for when a consensus must is "too early"

[asn at torproject.org]

commit 42d0a841acbd2d8f5a7e83a3b8e9425676eb0370
Author: Nick Mathewson <nickm at torproject.org>
Date:   Fri Sep 18 10:18:06 2020 -0400

    Better description for when a consensus must is "too early"
    
    Since the authorities can produce a signed consensus as soon as
    `ValidAfter` minus `DistSeconds`, and since they serve a signed
    consensus as soon as it has enough signatures, it's possible that a
    client or relay that's starting late in the hour can get an "early"
    consensus.  Back in tor#25756, we fixed this issue in Tor, but we
    didn't document the behavior in the spec.
---
 dir-spec.txt | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/dir-spec.txt b/dir-spec.txt
index 7ae5acd..27d380f 100644
--- a/dir-spec.txt
+++ b/dir-spec.txt
@@ -341,7 +341,8 @@
       change does remove one common cause of consensus splits.
 
    VA-DistSeconds: The authorities calculate the consensus and exchange
-   signatures.
+   signatures.  (This is the earliest point at which anybody can
+   possibly get a given consensus if they ask for it.)
 
    VA-DistSeconds/2: The authorities try to download any signatures
    they don't have.
@@ -1752,7 +1753,14 @@
         [Exactly once.]
 
         The start of the Interval for this vote.  Before this time, the
-        consensus document produced from this vote should not be used.
+        consensus document produced from this vote is not officially in
+        use.
+
+        (Note that because of propagation delays, clients and relays
+        may see consensus documents that are up to `DistSeconds`
+        earlier than this this time, and should not warn about
+        them.)
+
         See section 1.4 for voting timeline information.
 
     "fresh-until" SP YYYY-MM-DD SP HH:MM:SS NL