Don't print a "weird flag" type warning "[b2&3=0x2400]" for DNS NOTIFY

messages which should be sent with AA set. Adapted from a patch at
http://marc.info/?l=tcpdump-patches&m=98115734907026&w=2 pointed out by
Peter J. Philipp, ok henning@

diff --git a/usr.sbin/tcpdump/nameser.h b/usr.sbin/tcpdump/nameser.h
index b21b34d..8ae9c8b 100644 (file)
--- a/usr.sbin/tcpdump/nameser.h
+++ b/usr.sbin/tcpdump/nameser.h
@@ -1,4 +1,4 @@
-/* @(#) $Id: nameser.h,v 1.6 2010/11/04 17:37:05 canacar Exp $ (LBL) */
+/* @(#) $Id: nameser.h,v 1.7 2014/05/23 20:36:04 sthen Exp $ (LBL) */
 /*
  * Copyright (c) 1983, 1989, 1993
  *     The Regents of the University of California.  All rights reserved.
@@ -82,6 +82,8 @@
 #if 0
 #define xxx            0x3             /* 0x3 reserved */
 #endif
+#define NS_NOTIFY_OP   0x4             /* notify secondary of SOA change */
+
        /* non standard - supports ALLOW_UPDATES stuff from Mike Schwartz */
 #define UPDATEA                0x9             /* add resource record */
 #define UPDATED                0xa             /* delete a specific resource record */

diff --git a/usr.sbin/tcpdump/print-domain.c b/usr.sbin/tcpdump/print-domain.c
index bc9d3a7..3ea8037 100644 (file)
--- a/usr.sbin/tcpdump/print-domain.c
+++ b/usr.sbin/tcpdump/print-domain.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: print-domain.c,v 1.18 2010/11/04 17:37:05 canacar Exp $       */
+/*     $OpenBSD: print-domain.c,v 1.19 2014/05/23 20:36:04 sthen Exp $ */
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
@@ -663,9 +663,10 @@ ns_print(register const u_char *bp, u_int length, int is_mdns)
                    DNS_RD(np) ? "+" : "",
                    DNS_CD(np) ? "%" : "");
 
-               /* any weirdness? */
+               /* any weirdness? AA is expected in NOTIFY. */
                b2 = EXTRACT_16BITS(((u_short *)np)+1);
-               if (b2 & 0x6cf)
+               if ((b2 & 0x6cf) !=
+                   (DNS_OPCODE(np) == NS_NOTIFY_OP ? htons(0x400) : 0))
                        printf(" [b2&3=0x%x]", b2);
 
                if (DNS_OPCODE(np) == IQUERY) {