Move into "call_dissector_work()" the stuff to handle dissecting, in

error packets, the copy of the packet that got the error, rather than
doing it in the CLNP dissector and the ICMP dissector and the ICMPv6
dissector and the PPP dissector for various control protocols; have it
do that work iff "pinfo->in_error_pkt" is set.

svn path=/trunk/; revision=6942

1 files changed, 110 insertions, 12 deletions

diff --git a/epan/packet.c b/epan/packet.c
index ab50d0a614..7969171aae 100644
--- a/epan/packet.c
+++ b/epan/packet.c
@@ -1,7 +1,7 @@
 /* packet.c
  * Routines for packet disassembly
  *
- * $Id: packet.c,v 1.84 2002/12/08 02:32:36 gerald Exp $
+ * $Id: packet.c,v 1.85 2003/01/20 05:42:37 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -335,6 +335,29 @@ struct dissector_handle {
 	int		proto_index;
 };
 
+static int
+call_dissector_through_handle(dissector_handle_t handle, tvbuff_t *tvb,
+    packet_info *pinfo, proto_tree *tree)
+{
+	int ret;
+
+	if (handle->is_new)
+		ret = (*handle->dissector.new)(tvb, pinfo, tree);
+	else {
+		(*handle->dissector.old)(tvb, pinfo, tree);
+		ret = tvb_length(tvb);
+		if (ret == 0) {
+			/*
+			 * XXX - a tvbuff can have 0 bytes of data in
+			 * it, so we have to make sure we don't return
+			 * 0.
+			 */
+			ret = 1;
+		}
+	}
+	return ret;
+}
+
 /*
  * Call a dissector through a handle.
  * If the protocol for that handle isn't enabled, return 0 without
@@ -349,7 +372,14 @@ call_dissector_work(dissector_handle_t handle, tvbuff_t *tvb,
 {
 	const char *saved_proto;
 	guint16 saved_can_desegment;
-	int ret;
+	volatile int ret;
+	gboolean save_writable;
+	volatile address save_dl_src;
+	volatile address save_dl_dst;
+	volatile address save_net_src;
+	volatile address save_net_dst;
+	volatile address save_src;
+	volatile address save_dst;
 
 	if (handle->proto_index != -1 &&
 	    !proto_is_protocol_enabled(handle->proto_index)) {
@@ -375,19 +405,87 @@ call_dissector_work(dissector_handle_t handle, tvbuff_t *tvb,
 		pinfo->current_proto =
 		    proto_get_protocol_short_name(handle->proto_index);
 	}
-	if (handle->is_new)
-		ret = (*handle->dissector.new)(tvb, pinfo, tree);
-	else {
-		(*handle->dissector.old)(tvb, pinfo, tree);
-		ret = tvb_length(tvb);
-		if (ret == 0) {
+
+	if (pinfo->in_error_pkt) {
+		/*
+		 * This isn't a packet being transported inside
+		 * the protocol whose dissector is calling us,
+		 * it's a copy of a packet that caused an error
+		 * in some protocol included in a packet that
+		 * reports the error (e.g., an ICMP Unreachable
+		 * packet).
+		 */
+
+		/*
+		 * Save the current state of the writability of
+		 * the columns, and restore them after the
+		 * dissector returns, so that the columns
+		 * don't reflect the packet that got the error,
+		 * they reflect the packet that reported the
+		 * error.
+		 */
+		save_writable = col_get_writable(pinfo->cinfo);
+		col_set_writable(pinfo->cinfo, FALSE);
+	 	save_dl_src = pinfo->dl_src;
+		save_dl_dst = pinfo->dl_dst;
+		save_net_src = pinfo->net_src;
+		save_net_dst = pinfo->net_dst;
+		save_src = pinfo->src;
+		save_dst = pinfo->dst;
+
+		/* Dissect the contained packet. */
+		TRY {
+			ret = call_dissector_through_handle(handle, tvb,
+			    pinfo, tree);
+		}
+		CATCH(BoundsError) {
 			/*
-			 * XXX - a tvbuff can have 0 bytes of data in
-			 * it, so we have to make sure we don't return
-			 * 0.
+			 * Restore the column writability and addresses.
 			 */
-			ret = 1;
+			col_set_writable(pinfo->cinfo, save_writable);
+			pinfo->dl_src = save_dl_src;
+			pinfo->dl_dst = save_dl_dst;
+			pinfo->net_src = save_net_src;
+			pinfo->net_dst = save_net_dst;
+			pinfo->src = save_src;
+			pinfo->dst = save_dst;
+
+			/*
+			 * Restore the current protocol, so any
+			 * "Short Frame" indication reflects that
+			 * protocol, not the protocol for the
+			 * packet that got the error.
+			 */
+			pinfo->current_proto = saved_proto;
+
+			/*
+			 * Restore the desegmentability state.
+			 */
+			pinfo->can_desegment = saved_can_desegment;
+
+			/*
+			 * Rethrow the exception, so this will be
+			 * reported as a short frame.
+			 */
+			RETHROW;
+		}
+		CATCH(ReportedBoundsError) {
+			; /* do nothing */
 		}
+		ENDTRY;
+
+		col_set_writable(pinfo->cinfo, save_writable);
+		pinfo->dl_src = save_dl_src;
+		pinfo->dl_dst = save_dl_dst;
+		pinfo->net_src = save_net_src;
+		pinfo->net_dst = save_net_dst;
+		pinfo->src = save_src;
+		pinfo->dst = save_dst;
+	} else {
+		/*
+		 * Just call the subdissector.
+		 */
+		ret = call_dissector_through_handle(handle, tvb, pinfo, tree);
 	}
 	pinfo->current_proto = saved_proto;
 	pinfo->can_desegment = saved_can_desegment;