[tor-commits] [torspec/master] Clarify that 0 is the only reserved circID value

[nickm at torproject.org]

commit 78de0f958204b463e6dbf64831d925a21c4350cf
Author: Nick Mathewson <nickm at torproject.org>
Date:   Wed Apr 23 11:31:27 2014 -0400

    Clarify that 0 is the only reserved circID value
    
    Fixes 11565.
---
 tor-spec.txt |    4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tor-spec.txt b/tor-spec.txt
index 604a1e7..2555af4 100644
--- a/tor-spec.txt
+++ b/tor-spec.txt
@@ -761,6 +761,10 @@ see tor-design.pdf.
    (An OP with no public key MAY choose any CircID it wishes, since an OP
    never needs to process a CREATE cell.)
 
+   The CircID value 0 is specifically reserved for cells that do not
+   belong to any circuit: CircID 0 must not be used for circuits.  No
+   other CircID value, including 0x8000 or 0x80000000, is reserved.
+
 5.1.2. EXTEND and EXTENDED cells
 
    To extend an existing circuit, the client sends a EXTEND or EXTENDED2