From efcd38346161b10d60368411cfb2c0d1c22b5fb1 Mon Sep 17 00:00:00 2001
From: Brian Wellington <source@isc.org>
Date: Fri, 5 Jan 2001 00:17:33 +0000
Subject: [PATCH] Update forwarding when the message buffer was no longer
 copied.  Fix this by having the update forwarding code tell dns_message_parse
 to copy the buffer.

---
 lib/dns/include/dns/message.h |  6 +++++-
 lib/dns/message.c             | 34 +++++++++++++++++++++++++++-------
 lib/dns/zone.c                |  5 +++--
 3 files changed, 35 insertions(+), 10 deletions(-)

diff --git a/lib/dns/include/dns/message.h b/lib/dns/include/dns/message.h
index 2ee2a6ebfa..d72c9493e8 100644
--- a/lib/dns/include/dns/message.h
+++ b/lib/dns/include/dns/message.h
@@ -15,7 +15,7 @@
  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: message.h,v 1.85 2001/01/04 01:25:08 bwelling Exp $ */
+/* $Id: message.h,v 1.86 2001/01/05 00:17:33 bwelling Exp $ */
 
 #ifndef DNS_MESSAGE_H
 #define DNS_MESSAGE_H 1
@@ -149,6 +149,8 @@ typedef int dns_messagetextflag_t;
 #define DNS_MESSAGEPARSE_BESTEFFORT	0x0002	/* return a message if a
 						   recoverable parse error
 						   occurs */
+#define DNS_MESSAGEPARSE_CLONEBUFFER	0x0004	/* save a copy of the
+						   source buffer */
 
 /*
  * Control behavior of rendering
@@ -185,6 +187,8 @@ struct dns_message {
 	unsigned int			tcp_continuation : 1;
 	unsigned int			verified_sig : 1;
 	unsigned int			verify_attempted : 1;
+	unsigned int			free_query : 1;
+	unsigned int			free_saved : 1;
 
 	unsigned int			opt_reserved;
 	unsigned int			sig_reserved;
diff --git a/lib/dns/message.c b/lib/dns/message.c
index cf48d0514a..5e1428a937 100644
--- a/lib/dns/message.c
+++ b/lib/dns/message.c
@@ -15,7 +15,7 @@
  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: message.c,v 1.167 2001/01/04 01:55:22 bwelling Exp $ */
+/* $Id: message.c,v 1.168 2001/01/05 00:17:29 bwelling Exp $ */
 
 /***
  *** Imports
@@ -355,11 +355,6 @@ msginittsig(dns_message_t *m) {
 	m->sigstart = -1;
 	m->sig0key = NULL;
 	m->sig0status = dns_rcode_noerror;
-	m->query.base = NULL;
-	m->query.length = 0;
-	m->saved.base = NULL;
-	m->saved.length = 0;
-	m->querytsig = NULL;
 }
 
 /*
@@ -378,6 +373,13 @@ msginit(dns_message_t *m) {
 	m->verify_attempted = 0;
 	m->order = NULL;
 	m->order_arg = NULL;
+	m->query.base = NULL;
+	m->query.length = 0;
+	m->free_query = 0;
+	m->saved.base = NULL;
+	m->saved.length = 0;
+	m->free_saved = 0;
+	m->querytsig = NULL;
 }
 
 static inline void
@@ -558,11 +560,17 @@ msgreset(dns_message_t *msg, isc_boolean_t everything) {
 	}
 
 	if (msg->query.base != NULL) {
+		if (msg->free_query != 0)
+			isc_mem_put(msg->mctx, msg->query.base,
+				    msg->query.length);
 		msg->query.base = NULL;
 		msg->query.length = 0;
 	}
 
 	if (msg->saved.base != NULL) {
+		if (msg->free_saved != 0)
+			isc_mem_put(msg->mctx, msg->saved.base,
+				    msg->saved.length);
 		msg->saved.base = NULL;
 		msg->saved.length = 0;
 	}
@@ -1538,7 +1546,17 @@ dns_message_parse(dns_message_t *msg, isc_buffer_t *source,
 			      r.length);
 	}
 
-	isc_buffer_usedregion(&origsource, &msg->saved);
+	if ((options & DNS_MESSAGEPARSE_CLONEBUFFER) == 0)
+		isc_buffer_usedregion(&origsource, &msg->saved);
+	else {
+		msg->saved.length = isc_buffer_usedlength(&origsource);
+		msg->saved.base = isc_mem_get(msg->mctx, msg->saved.length);
+		if (msg->saved.base == NULL)
+			return (ISC_R_NOMEMORY);
+		memcpy(msg->saved.base, isc_buffer_base(&origsource),
+		       msg->saved.length);
+		msg->free_saved = 1;
+	}
 
 	if (seen_problem == ISC_TRUE)
 		return (DNS_R_RECOVERABLE);
@@ -2255,8 +2273,10 @@ dns_message_reply(dns_message_t *msg, isc_boolean_t want_question_section) {
 	if (msg->saved.base != NULL) {
 		msg->query.base = msg->saved.base;
 		msg->query.length = msg->saved.length;
+		msg->free_query = msg->free_saved;
 		msg->saved.base = NULL;
 		msg->saved.length = 0;
+		msg->free_saved = 0;
 	}
 
 	return (ISC_R_SUCCESS);
diff --git a/lib/dns/zone.c b/lib/dns/zone.c
index 9a250f01f3..8aaa53e669 100644
--- a/lib/dns/zone.c
+++ b/lib/dns/zone.c
@@ -15,7 +15,7 @@
  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
-/* $Id: zone.c,v 1.287 2001/01/04 04:10:59 marka Exp $ */
+/* $Id: zone.c,v 1.288 2001/01/05 00:17:31 bwelling Exp $ */
 
 #include <config.h>
 
@@ -4993,7 +4993,8 @@ forward_callback(isc_task_t *task, isc_event_t *event) {
 		goto next_master;
 
 	result = dns_request_getresponse(revent->request, msg,
-					 DNS_MESSAGEPARSE_PRESERVEORDER);
+					 DNS_MESSAGEPARSE_PRESERVEORDER |
+					 DNS_MESSAGEPARSE_CLONEBUFFER);
 	if (result != ISC_R_SUCCESS)
 		goto next_master;