[Ocfs2-tools-devel] [PATCH 1/1] wireshark-ocfs2: add dlm_query_join response handler

[Jeff Liu]

 this patch add the handler against dlm_query_join_response message, it
 could deal with both ocfs2-1.2.x and the newer packet layout.

 for ocfs2-1.4.x and the newer, the response status will be dissected and shown as:
	 Status: Value (response_code:dlm_minor:fs_minor)

Signed-off-by: Jeff Liu <jeff.liu at oracle.com>
---
 epan/dissectors/packet-ocfs2.c |   54 +++++++++++++++++++++++++++++++++++++--
 1 files changed, 51 insertions(+), 3 deletions(-)

diff --git a/epan/dissectors/packet-ocfs2.c b/epan/dissectors/packet-ocfs2.c
index ce57c3f..a4f07cc 100644
--- a/epan/dissectors/packet-ocfs2.c
+++ b/epan/dissectors/packet-ocfs2.c
@@ -229,12 +229,27 @@ const char * decode_enumerated_bitfield_full(guint32 val, guint32 mask, int widt
 #define DLM_LVB_LEN  64
 #define DLM_MOD_KEY (0x666c6172)
 
-enum dlm_query_join_response {
+enum dlm_query_join_response_code {
 	JOIN_DISALLOW = 0,
 	JOIN_OK,
 	JOIN_OK_NO_MAP,
+	JOIN_PROTOCOL_MISMATCH,
 };
 
+struct dlm_query_join_packet {
+	guint8 code;		/* Response code. dlm_minor and fs_minor
+				 are only valid if this is JOIN_OK */
+	guint8 dlm_minor;	/* The minor version of the protocol the
+				dlm is speaking. */
+	guint8 fs_minor;	/* The minor version of the protocol the
+				filesystem is speaking. */
+	guint8 reserved;
+};
+
+union dlm_query_join_response {
+	guint32 intval;
+	struct dlm_query_join_packet packet;
+};
 
 /* DLM lock modes */
 enum {
@@ -1148,10 +1163,37 @@ static void msg_struct_enumerate_fields(struct dlm_msg_struct_def *def, proto_tr
 	}
 }
 
+static void dissect_dlm_query_join_response(proto_tree *tree,
+					    proto_item *item,
+					    tvbuff_t *tvb,
+					    int offset)
+{
+	union dlm_query_join_response response;
+	struct dlm_query_join_packet packet;
+	guint32 status;
+
+	status = tvb_get_ntohl(tvb, offset);
+
+	/* NOP if ocfs2-1.2.x message coming */
+	if (status < JOIN_PROTOCOL_MISMATCH)
+		return ;
+
+	/* for ocfs2-1.4.x and newer */
+	response.intval = htonl(status);
+	packet = response.packet;
+	proto_item_append_text(item, " (%u:", packet.code);
+
+	if (packet.code == JOIN_OK)
+		proto_item_append_text(item, "%u:%u",
+					packet.dlm_minor, packet.fs_minor);
+
+	proto_item_append_text(item, ")");
+}
+
 static int dissect_ocfs2(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 {
 	proto_tree *subtree = NULL;
-	proto_item *ti;
+	proto_item *ti, *si;
 	guint16 len, magic, msg_type;
 	int ret;
 
@@ -1188,7 +1230,7 @@ static int dissect_ocfs2(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 		proto_tree_add_item(subtree, hf_msg_sys_status,
 				    tvb, O2NET_MSG_HDR_OFF_SYS_STATUS, 4,
 				    FALSE);
-		proto_tree_add_item(subtree, hf_msg_status,
+		si = proto_tree_add_item(subtree, hf_msg_status,
 				    tvb, O2NET_MSG_HDR_OFF_STATUS, 4,
 				    FALSE);
 		proto_tree_add_item(subtree, hf_msg_key,
@@ -1240,6 +1282,12 @@ static int dissect_ocfs2(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 			}
 		}
 
+		if (msg_type == DLM_QUERY_JOIN_MSG) {
+			if (magic == O2NET_MSG_STATUS_MAGIC)
+				dissect_dlm_query_join_response(subtree,
+					si, tvb, O2NET_MSG_HDR_OFF_STATUS);
+			goto out;
+		}
 
 		if (magic == O2NET_MSG_MAGIC) {
 			struct dlm_msg_struct_def *def;
-- 
1.5.4.3