From: Ted Lemon <source@isc.org>
Date: Tue, 17 Mar 1998 18:14:51 +0000 (+0000)
Subject: If we happen across an abandoned lease when trying to find a lease to allocate, try... 
X-Git-Tag: carrel-2~148
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=48984237a157864707118bad783cdcd7ec765016;p=thirdparty%2Fdhcp.git

If we happen across an abandoned lease when trying to find a lease to allocate, try using the abandoned lease.   If the client asks for a lease on one address, but we find another lease that's also assigned to it, make every effort to free the duplicate lease, since a client can't have two leases on the same network at the same time.
---

diff --git a/server/dhcp.c b/server/dhcp.c
index 7a7d3e7f4..74898db58 100644
--- a/server/dhcp.c
+++ b/server/dhcp.c
@@ -42,7 +42,7 @@
 
 #ifndef lint
 static char copyright[] =
-"$Id: dhcp.c,v 1.60 1998/03/17 06:20:51 mellon Exp $ Copyright (c) 1995, 1996 The Internet Software Consortium.  All rights reserved.\n";
+"$Id: dhcp.c,v 1.61 1998/03/17 18:14:51 mellon Exp $ Copyright (c) 1995, 1996 The Internet Software Consortium.  All rights reserved.\n";
 #endif /* not lint */
 
 #include "dhcpd.h"
@@ -116,6 +116,15 @@ void dhcpdiscover (packet)
 			return;
 		}
 
+		/* 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 abandoned IP address %s.\n",
+			      piaddr (lease -> ip_addr));
+			lease -> flags &= ~ABANDONED_LEASE;
+		}
+
 		/* Try to find a host_decl that matches the client
 		   identifier or hardware address on the packet, and
 		   has no fixed IP address.   If there is one, hang
@@ -1290,6 +1299,16 @@ struct lease *find_lease (packet, share, ours)
 						     packet -> raw -> hlen,
 						     packet -> raw -> chaddr),
 				      ip_lease -> shared_network -> name);
+
+			/* If the client is REQUESTing the lease, it shouldn't
+			   still be using the old one, so we can free it for
+			   allocation.   This is only true if the duplicate
+			   lease is on the same network, of course. */
+
+			if (packet -> packet_type == DHCPREQUEST &&
+			    share == uid_lease -> shared_network)
+				dissociate_lease (uid_lease);
+
 			uid_lease = ip_lease;
 		}
 		ip_lease = (struct lease *)0;