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Wireshark-dev: [Wireshark-dev] [PATCH] wireshark: can't decode callback if didn't caught CREATE

From: fanchaoting <fanchaoting@xxxxxxxxxxxxxx>
Date: Fri, 11 Jan 2013 17:44:10 +0800
now i found that nfs kernel use 0x40000000 as callback program number.
the CREATE_SESSION and SETCLIENTID use 0x40000000 as callback program number,
and they didn't change it.

but i found that i use wireshark to decode nfsv4 callback procedures, it didn't
decode them if the wireshark or tcpdump didn't caught CREATE_SESSION and SETCLIENTID
packets before.

Signed-off-by: Fan Chaoting <fanchaoting@xxxxxxxxxxxxxx>

---
 epan/dissectors/packet-nfs.c |   10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/epan/dissectors/packet-nfs.c b/epan/dissectors/packet-nfs.c
index 63d1019..7b5ec88 100644
--- a/epan/dissectors/packet-nfs.c
+++ b/epan/dissectors/packet-nfs.c
@@ -7979,10 +7979,7 @@ dissect_nfs_cb_client4(tvbuff_t *tvb, int offset, proto_tree *tree)
 {
 	proto_tree *cb_location = NULL;
 	proto_item *fitem = NULL;
-	int cbprog;
 
-	cbprog = tvb_get_ntohl(tvb, offset);
-	reg_callback(cbprog);
 	offset = dissect_rpc_uint32(tvb, tree, hf_nfs_cb_program, offset);
 	fitem = proto_tree_add_text(tree, tvb, offset, 0, "cb_location");
 
@@ -8991,7 +8988,6 @@ dissect_nfs_argop4(tvbuff_t *tvb, int offset, packet_info *pinfo,
 	proto_tree *ftree = NULL;
 	proto_tree *newftree = NULL;
 	guint32 string_length;
-	int cbprog;
 	const char *name = NULL, *source_name = NULL, *dest_name=NULL;
 	const char *opname=NULL;
 	guint32 last_fh_hash=0;
@@ -9012,6 +9008,10 @@ dissect_nfs_argop4(tvbuff_t *tvb, int offset, packet_info *pinfo,
 		"Operations (count: %u)", ops);
 	offset += 4;
 
+	 /*Now the nfs use '0x40000000' as callback's program number.*/
+#define CB_PROG 0x40000000
+	reg_callback(CB_PROG);
+
 #define MAX_NFSV4_OPS 128
 
 	if (ops > MAX_NFSV4_OPS) {
@@ -9469,8 +9469,6 @@ dissect_nfs_argop4(tvbuff_t *tvb, int offset, packet_info *pinfo,
 			offset = dissect_nfs_create_session_flags(tvb, offset, newftree, hf_nfs_create_session_flags_csa);
 			offset = dissect_rpc_chanattrs4(tvb, offset, newftree, "csa_fore_chan_attrs");
 			offset = dissect_rpc_chanattrs4(tvb, offset, newftree, "csa_back_chan_attrs");
-			cbprog = tvb_get_ntohl(tvb, offset);
-			reg_callback(cbprog);
 			offset = dissect_rpc_uint32(tvb, newftree, hf_nfs_cb_program, offset);
 			offset = dissect_rpc_secparms4(tvb, offset, newftree);
 			break;
-- 
1.7.10.1

Attachment: callback.pcap
Description: Binary data