From: David Hankins <dhankins@isc.org>
Date: Fri, 30 Sep 2005 17:51:04 +0000 (+0000)
Subject: - Adjusted lease state validation checks in potential-conflict, to
X-Git-Tag: V3-0-4-BETA-1~14
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=cc5c3182b241c07103dc1b51bb067dcc94c0eefb;p=thirdparty%2Fdhcp.git

- Adjusted lease state validation checks in potential-conflict, to
  account for possible clock skew similarly to normal state, and several
  previously illegal transitions were made legal (ex: active->released).
  [ISC-Bugs #14834]
---

diff --git a/RELNOTES b/RELNOTES
index 4ebcc0623..9400e7ed3 100644
--- a/RELNOTES
+++ b/RELNOTES
@@ -95,6 +95,10 @@ and for prodding me into improving it.
 - Failover potential expiry calculations (TSTP) have been corrected.  Results
   should be substantially more consistent, and proper given the constraints.
 
+- Adjusted lease state validation checks in potential-conflict, to
+  account for possible clock skew similarly to normal state, and several
+  previously illegal transitions were made legal (ex: active->released).
+
 			Changes since 3.0.3b3
 
 - dhclient.conf documentation for interface {} was updated to reflect recent
diff --git a/server/failover.c b/server/failover.c
index 49a36d811..8ab2f33f6 100644
--- a/server/failover.c
+++ b/server/failover.c
@@ -34,7 +34,7 @@
 
 #ifndef lint
 static char copyright[] =
-"$Id: failover.c,v 1.53.2.40 2005/09/22 16:19:59 dhankins Exp $ Copyright (c) 2004-2005 Internet Systems Consortium.  All rights reserved.\n";
+"$Id: failover.c,v 1.53.2.41 2005/09/30 17:51:04 dhankins Exp $ Copyright (c) 2004-2005 Internet Systems Consortium.  All rights reserved.\n";
 #endif /* not lint */
 
 #include "dhcpd.h"
@@ -5283,21 +5283,29 @@ conflict_binding_state_transition_check (struct lease *lease,
 			switch (binding_state) {
 			      case FTS_FREE:
 			      case FTS_BACKUP:
-			      case FTS_ABANDONED:
 				new_state = lease -> binding_state;
 				break;
 
 			      case FTS_EXPIRED:
-			      case FTS_RELEASED:
-			      case FTS_RESET:
-				if (lease -> ends > cur_time)
-					new_state =
-						lease -> binding_state;
+				/* If we don't agree about expiry, it's
+				 * invalid.  65 should allow for max
+				 * clock skew (60) plus some fudge.
+				 * XXX: should we refetch cur_time?
+				 */
+				if ((lease->ends - 65) > cur_time)
+					new_state = lease->binding_state;
 				else
 					new_state = binding_state;
 				break;
 
-			      case FTS_ACTIVE:
+				/* RELEASED, RESET, and ABANDONED indicate
+				 * that our partner has information about
+				 * this lease that we did not witness.  Our
+				 * partner wins.
+				 */
+			      case FTS_RELEASED:
+			      case FTS_RESET:
+			      case FTS_ABANDONED:
 				new_state = binding_state;
 				break;