From fe849040b52ab4f49e3f55272ed48c4cc80dcafd Mon Sep 17 00:00:00 2001
From: Ted Lemon <source@isc.org>
Date: Wed, 20 Oct 1999 16:47:04 +0000
Subject: [PATCH] Handle 'allow bootp' and 'allow booting' correctly.   Unicast
 if possible.

---
 server/bootp.c | 29 ++++++++++++++++++-----------
 1 file changed, 18 insertions(+), 11 deletions(-)

diff --git a/server/bootp.c b/server/bootp.c
index 224e93e5..a5dce15b 100644
--- a/server/bootp.c
+++ b/server/bootp.c
@@ -22,7 +22,7 @@
 
 #ifndef lint
 static char copyright[] =
-"$Id: bootp.c,v 1.55 1999/10/07 06:36:29 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998, 1999 The Internet Software Consortium.  All rights reserved.\n";
+"$Id: bootp.c,v 1.56 1999/10/20 16:47:04 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998, 1999 The Internet Software Consortium.  All rights reserved.\n";
 #endif /* not lint */
 
 #include "dhcpd.h"
@@ -134,22 +134,19 @@ void bootp (packet)
 				     hp -> group, subnet -> group);
 	
 	/* Drop the request if it's not allowed for this client. */
-	if (evaluate_boolean_option_cache (packet, lease,
-					   packet -> options, options, 
-					   lookup_option (&server_universe,
-							  options,
-							  SV_ALLOW_BOOTP))) {
+	if ((oc = lookup_option (&server_universe, options, SV_ALLOW_BOOTP)) &&
+	    !evaluate_boolean_option_cache (packet, lease,
+					    packet -> options, options, oc)) {
 		log_info ("%s: bootp disallowed", msgbuf);
 		option_state_dereference (&options, "bootrequest");
 		static_lease_dereference (lease, "bootrequest");
 		return;
 	} 
 
-	if (evaluate_boolean_option_cache (packet, lease,
-					   packet -> options, options, 
-					   lookup_option (&server_universe,
-							  options,
-							  SV_ALLOW_BOOTING))) {
+	if ((oc = lookup_option (&server_universe,
+				 options, SV_ALLOW_BOOTING)) &&
+	    !evaluate_boolean_option_cache (packet, lease,
+					    packet -> options, options, oc)) {
 		log_info ("%s: booting disallowed", msgbuf);
 		option_state_dereference (&options, "bootrequest");
 		static_lease_dereference (lease, "bootrequest");
@@ -317,6 +314,16 @@ void bootp (packet)
 					      from, &to, &hto);
 			return;
 		}
+
+	/* If it comes from a client that already knows its address
+	   and is not requesting a broadcast response, and we can
+	   unicast to a client without using the ARP protocol, sent it
+	   directly to that client. */
+	} else if (!(raw.flags & htons (BOOTP_BROADCAST)) &&
+		   can_unicast_without_arp (packet -> interface)) {
+		to.sin_addr = raw.yiaddr;
+		to.sin_port = remote_port;
+
 	/* Otherwise, broadcast it on the local network. */
 	} else {
 		to.sin_addr = limited_broadcast;