From: krw <krw@openbsd.org>
Date: Mon, 18 May 2015 14:59:42 +0000 (+0000)
Subject: Stop rejecting leases with a subnet that overlaps a subnet already
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=0c028e371b5a75a07a5795e8dec556e50ae9f787;p=openbsd

Stop rejecting leases with a subnet that overlaps a subnet already
present. The latest routing stack code can now handle these situations.

Much requested by beck@ and others. Detailed discussion at s2k15
identified required routing changes.

ok claudio@
---

diff --git a/sbin/dhclient/dhclient.c b/sbin/dhclient/dhclient.c
index d280bac73a9..9c74c776ccf 100644
--- a/sbin/dhclient/dhclient.c
+++ b/sbin/dhclient/dhclient.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dhclient.c,v 1.360 2015/04/16 15:14:30 gsoares Exp $	*/
+/*	$OpenBSD: dhclient.c,v 1.361 2015/05/18 14:59:42 krw Exp $	*/
 
 /*
  * Copyright 2004 Henning Brauer <henning@openbsd.org>
@@ -1060,13 +1060,6 @@ dhcpoffer(struct in_addr client_addr, struct option_data *options, char *info)
 		return;
 	}
 
-	/*
-	 * Reject offers whose subnet is already configured on another
-	 * interface.
-	 */
-	if (subnet_exists(lease))
-		return;
-
 	/*
 	 * If this lease was acquired through a BOOTREPLY, record that
 	 * fact.
diff --git a/sbin/dhclient/dhcpd.h b/sbin/dhclient/dhcpd.h
index c773eef5c44..945aa00417f 100644
--- a/sbin/dhclient/dhcpd.h
+++ b/sbin/dhclient/dhcpd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dhcpd.h,v 1.149 2015/02/10 04:20:26 krw Exp $	*/
+/*	$OpenBSD: dhcpd.h,v 1.150 2015/05/18 14:59:42 krw Exp $	*/
 
 /*
  * Copyright (c) 2004 Henning Brauer <henning@openbsd.org>
@@ -261,7 +261,6 @@ void interface_link_forceup(char *);
 int interface_status(char *);
 int get_rdomain(char *);
 void get_hw_address(void);
-int subnet_exists(struct client_lease *);
 
 /* tables.c */
 extern const struct option dhcp_options[256];
diff --git a/sbin/dhclient/dispatch.c b/sbin/dhclient/dispatch.c
index 2cb7cc936a6..11e33478f7f 100644
--- a/sbin/dhclient/dispatch.c
+++ b/sbin/dhclient/dispatch.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dispatch.c,v 1.101 2015/04/16 15:14:31 gsoares Exp $	*/
+/*	$OpenBSD: dispatch.c,v 1.102 2015/05/18 14:59:42 krw Exp $	*/
 
 /*
  * Copyright 2004 Henning Brauer <henning@openbsd.org>
@@ -343,70 +343,3 @@ get_rdomain(char *name)
 	close(s);
 	return rv;
 }
-
-int
-subnet_exists(struct client_lease *l)
-{
-	struct option_data *opt;
-	struct ifaddrs *ifap, *ifa;
-	struct in_addr mymask, myaddr, mynet, hismask, hisaddr, hisnet;
-	int myrdomain, hisrdomain;
-
-	opt = &l->options[DHO_SUBNET_MASK];
-	if (opt->len == sizeof(mymask))
-		mymask.s_addr = ((struct in_addr *)opt->data)->s_addr;
-	else
-		mymask.s_addr = INADDR_ANY;
-	myaddr.s_addr = l->address.s_addr;
-	mynet.s_addr = mymask.s_addr & myaddr.s_addr;
-
-	myrdomain = get_rdomain(ifi->name);
-
-	if (getifaddrs(&ifap) != 0)
-		error("getifaddrs failed");
-
-	for (ifa = ifap; ifa != NULL; ifa = ifa->ifa_next) {
-		if (strcmp(ifi->name, ifa->ifa_name) == 0)
-			continue;
-
-		if (ifa->ifa_addr->sa_family != AF_INET)
-			continue;
-
-		hisrdomain = get_rdomain(ifa->ifa_name);
-		if (hisrdomain != myrdomain)
-			continue;
-
-		memcpy(&hismask,
-		    &((struct sockaddr_in *)ifa->ifa_netmask)->sin_addr,
-		    sizeof(hismask));
-		memcpy(&hisaddr,
-		    &((struct sockaddr_in *)ifa->ifa_addr)->sin_addr,
-		    sizeof(hisaddr));
-		hisnet.s_addr = hisaddr.s_addr & hismask.s_addr;
-
-		if (hisnet.s_addr == INADDR_ANY)
-			continue;
-
-		/* Would his packets go out *my* interface? */
-		if (mynet.s_addr == (hisaddr.s_addr & mymask.s_addr)) {
-			note("interface %s already has the offered subnet!",
-			    ifa->ifa_name);
-			break;
-		}
-
-		/* Would my packets go out *his* interface? */
-		if (hisnet.s_addr == (myaddr.s_addr & hismask.s_addr)) {
-			note("interface %s already has the offered subnet!",
-			    ifa->ifa_name);
-			break;
-		}
-	}
-
-	freeifaddrs(ifap);
-
-	/* If ifa == NULL we scanned the list without finding a problem. */
-	if (ifa == NULL)
-		return (0);
-	else
-		return (1);
-}