Changed the behavior when an interface-direct prefix being advertised

was removed from the kernel;
Advertise the prefix with zero lifetimes rather than to remove the prefix
from the prefix list to be advertised.
This will help renumber a receiving host by deprecating the address
derived from the old prefix.

Obtained from:	KAME
MFC after:	2 weeks

1 files changed, 11 insertions, 3 deletions

diff --git a/usr.sbin/rtadvd/rtadvd.c b/usr.sbin/rtadvd/rtadvd.c
index 88a0a3dbeca6..9e8c81eaaf77 100644
--- a/usr.sbin/rtadvd/rtadvd.c
+++ b/usr.sbin/rtadvd/rtadvd.c
@@ -450,7 +450,13 @@ rtmsg_input()
 			}
 			prefix = find_prefix(rai, addr, plen);
 			if (prefix) {
-				if (dflag > 1) {
+				if (prefix->timer) {
+					/*
+					 * If the prefix has been invalidated,
+					 * make it available again.
+					 */
+					update_prefix(prefix);
+				} else if (dflag > 1) {
 					syslog(LOG_DEBUG,
 					    "<%s> new prefix(%s/%d) "
 					    "added on %s, "
@@ -497,7 +503,7 @@ rtmsg_input()
 				}
 				break;
 			}
-			delete_prefix(rai, prefix);
+			invalidate_prefix(prefix);
 			break;
 		case RTM_NEWADDR:
 		case RTM_DELADDR:
@@ -1550,7 +1556,7 @@ struct rainfo *rainfo;
 }
 
 /* process RA timer */
-void
+struct rtadvd_timer *
 ra_timeout(void *data)
 {
 	struct rainfo *rai = (struct rainfo *)data;
@@ -1564,6 +1570,8 @@ ra_timeout(void *data)
 	       __FUNCTION__, rai->ifname);
 
 	ra_output(rai);
+
+	return(rai->timer);
 }
 
 /* update RA timer */