If a client REQUESTs an abandoned lease, reclaim it.

diff --git a/server/dhcp.c b/server/dhcp.c
index 3b89417ba2f9863417c1e755f1667b96732a1d9d..c4ba3612456e54ad4c4053a37a6b4e3e7750c031 100644 (file)
--- a/server/dhcp.c
+++ b/server/dhcp.c
@@ -42,7 +42,7 @@
 
 #ifndef lint
 static char copyright[] =
-"$Id: dhcp.c,v 1.64 1998/06/25 03:56:24 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998 The Internet Software Consortium.  All rights reserved.\n";
+"$Id: dhcp.c,v 1.65 1998/06/25 21:24:23 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998 The Internet Software Consortium.  All rights reserved.\n";
 #endif /* not lint */
 
 #include "dhcpd.h"
@@ -1309,9 +1309,13 @@ struct lease *find_lease (packet, share, ours)
                *ours = 1;
 
        /* If the requested IP address isn't on the network the packet
-          came from, or if it's been abandoned, don't use it. */
-       if (ip_lease && (ip_lease -> shared_network != share ||
-                        (ip_lease -> flags & ABANDONED_LEASE)))
+          came from, don't use it.  Allow abandoned leases to be matched
+          here - if the client is requesting it, there's a decent chance
+          that it's because the lease database got trashed and a client
+          that thought it had this lease answered an ARP or PING, causing the
+          lease to be abandoned.   If so, this request probably came from
+          that client. */
+       if (ip_lease && (ip_lease -> shared_network != share))
                ip_lease = (struct lease *)0;
 
        /* Toss ip_lease if it hasn't yet expired and the uid doesn't
@@ -1457,6 +1461,15 @@ struct lease *find_lease (packet, share, ours)
                }
        }
 
+       /* If we find an abandoned lease, take it, but print a
+          warning message, so that if it continues to lose,
+          the administrator will eventually investigate. */
+       if (lease -> flags & ABANDONED_LEASE) {
+               warn ("Reclaiming REQUESTed abandoned IP address %s.\n",
+                     piaddr (lease -> ip_addr));
+               lease -> flags &= ~ABANDONED_LEASE;
+       }
+
        return lease;
 }