[Bug 2952] Symmetric active/passive mode is broken

bk: 570c6ae5vw7A2_B1ZftvU7eCqS-xaw

diff --git a/ChangeLog b/ChangeLog
index 77f9af2b052758fbf526e30a47a60b9f715f7fcf..5165c17abe30f2b0a391087ec8de779c86d3823d 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -12,6 +12,7 @@
 * [Bug 2879] Improve NTP security against timing attacks. perlinger@ntp.org
   - integrated patches by Loganaden Velvidron <logan@ntp.org>
     with some modifications & unit tests
+* [Bug 2952] Symmetric active/passive mode is broken.  HStenn.
 * [Bug 2960] async name resolution fixes for chroot() environments.
   Reinhard Max.
 * [Bug 2994] Systems with HAVE_SIGNALED_IO fail to compile. perlinger@ntp.org

diff --git a/ntpd/ntp_proto.c b/ntpd/ntp_proto.c
index 5c8be69710342ade49a488ee3041a783dbe59006..fefc7d5445c579b4e8578db78c9a39194ff25ca7 100644 (file)
--- a/ntpd/ntp_proto.c
+++ b/ntpd/ntp_proto.c
@@ -172,7 +172,8 @@ int unpeer_crypto_early             = 1;    /* bad crypto (TEST9) */
 int unpeer_crypto_nak_early    = 1;    /* crypto_NAK (TEST5) */
 int unpeer_digest_early                = 1;    /* bad digest (TEST5) */
 
-static int kiss_code_check(u_char hisleap, u_char hisstratum, u_char hismode, u_int32 refid);
+int kiss_code_check(u_char hisleap, u_char hisstratum, u_char hismode, u_int32 refid);
+enum nak_error_codes valid_NAK(struct peer *peer, struct recvbuf *rbufp, u_char hismode);
 static double  root_distance   (struct peer *);
 static void    clock_combine   (peer_select *, int, int);
 static void    peer_xmit       (struct peer *);
@@ -1592,9 +1593,9 @@ receive(
         * If there is no origin timestamp, it's either an initial packet
         * or we've already received a response to our query.  Of course,
         * should 'aorg' be all-zero because this really was the original
-        * transmit timestamp, we'll drop the reply.  There is a window of
-        * one nanosecond once every 136 years' time where this is possible.
-        * We currently ignore this situation.
+        * transmit timestamp, we'll ignore this reply.  There is a window
+        * of one nanosecond once every 136 years' time where this is
+        * possible.  We currently ignore this situation.
         *
         * Otherwise, check for bogus packet in basic mode.
         * If it is bogus, switch to interleaved mode and resynchronize,
@@ -1605,14 +1606,23 @@ receive(
         * be from us, attempting to cause our server to KoD us.
         */
        } else if (peer->flip == 0) {
-               if (    L_ISZERO(&peer->aorg)
-                   || !L_ISEQU(&p_org, &peer->aorg)) {
+               INSIST(0 != hisstratum);
+               if (0) {
+               } else if (L_ISZERO(&p_org)) {
+                       msyslog(LOG_INFO,
+                               "receive: Got 0 origin timestamp from %s@%s xmt %#010x.%08x",
+                               hm_str, ntoa(&peer->srcadr),
+                               ntohl(pkt->xmt.l_ui), ntohl(pkt->xmt.l_uf));
+                       L_CLR(&peer->aorg);
+               } else if (!L_ISEQU(&p_org, &peer->aorg)) {
+                       /* are there cases here where we should bail? */
+                       /* Should we set TEST2 if we decide to try xleave? */
                        peer->bogusorg++;
                        peer->flash |= TEST2;   /* bogus */
                        msyslog(LOG_INFO,
-                               "receive: Unexpected origin timestamp %#010x.%08x from %s xmt %#010x.%08x",
+                               "receive: Unexpected origin timestamp %#010x.%08x from %s@%s xmt %#010x.%08x",
                                ntohl(pkt->org.l_ui), ntohl(pkt->org.l_uf),
-                               ntoa(&peer->srcadr),
+                               hm_str, ntoa(&peer->srcadr),
                                ntohl(pkt->xmt.l_ui), ntohl(pkt->xmt.l_uf));
                        if (  !L_ISZERO(&peer->dst)
                            && L_ISEQU(&p_org, &peer->dst)) {
@@ -1620,10 +1630,9 @@ receive(
                                peer->flip = 1;
                                report_event(PEVNT_XLEAVE, peer, NULL);
                        }
-                       /* HMS: Do we want to return here if it's xleave? */
-                       return; /* Bogus or possible interleave packet */
+               } else {
+                       L_CLR(&peer->aorg);
                }
-               L_CLR(&peer->aorg);
 
        /*
         * Check for valid nonzero timestamp fields.