Restore pre-a2k19 behaviour of clearing out all existing addresses

when setting new address.

That change needs specific consideration rather than inadvertant
inclusion, especially after claiming no functional change was
being made.

Change and related problems noted and reversion tested by Kurt
Mosiejczuk.

1 files changed, 14 insertions, 10 deletions

diff --git a/sbin/dhclient/kroute.c b/sbin/dhclient/kroute.c
index c2d4699a060..dc38e7103ad 100644
--- a/sbin/dhclient/kroute.c
+++ b/sbin/dhclient/kroute.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kroute.c,v 1.159 2019/02/12 16:50:44 krw Exp $	*/
+/*	$OpenBSD: kroute.c,v 1.160 2019/02/23 13:24:19 krw Exp $	*/
 
 /*
  * Copyright 2012 Kenneth R Westerback <krw@openbsd.org>
@@ -51,7 +51,7 @@
 #define ROUNDUP(a) \
 	((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
 
-int		 find_address(char *, struct in_addr, struct in_addr);
+int		 delete_addresses(char *, int, struct in_addr, struct in_addr);
 void		 set_address(char *, int, struct in_addr, struct in_addr);
 void		 delete_address(char *, int, struct in_addr);
 
@@ -72,20 +72,23 @@ char		*set_resolv_conf(char *, uint8_t *, unsigned int,
 void		 set_mtu(char *, int, uint16_t);
 
 /*
- * find_address() attempts to find newaddr/newmask in the addresses configured
- * on the named interface.
+ * delete_addresses() removes all inet addresses on the named interface, except
+ * for newaddr/newnetmask.
  *
- * If the new addr/mask is already present, return 0, else 1.
+ * If newaddr/newmask is already present, return 0, else 1.
  */
 int
-find_address(char *name, struct in_addr newaddr, struct in_addr newnetmask)
+delete_addresses(char *name, int ioctlfd, struct in_addr newaddr,
+    struct in_addr newnetmask)
 {
 	struct in_addr			 addr, netmask;
 	struct ifaddrs			*ifap, *ifa;
+	int				 found;
 
 	if (getifaddrs(&ifap) != 0)
 		fatal("getifaddrs");
 
+	found = 0;
 	for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
 		if ((ifa->ifa_flags & IFF_LOOPBACK) != 0 ||
 		    (ifa->ifa_flags & IFF_POINTOPOINT) != 0 ||
@@ -103,13 +106,14 @@ find_address(char *name, struct in_addr newaddr, struct in_addr newnetmask)
 
 		if (addr.s_addr == newaddr.s_addr &&
 		    netmask.s_addr == newnetmask.s_addr) {
-			freeifaddrs(ifap);
-			return 0;
+			found = 1;
+		} else {
+			delete_address(name, ioctlfd, addr);
 		}
 	}
 
 	freeifaddrs(ifap);
-	return 1;
+	return found;
 }
 
 /*
@@ -124,7 +128,7 @@ set_address(char *name, int ioctlfd, struct in_addr addr,
 	struct ifaliasreq	 ifaliasreq;
 	struct sockaddr_in	*in;
 
-	if (find_address(name, addr, netmask) == 0)
+	if (delete_addresses(name, ioctlfd, addr, netmask) == 1)
 		return;
 
 	memset(&ifaliasreq, 0, sizeof(ifaliasreq));