[Ocfs2-tools-devel] [PATCH 1/1] wireshark-ocfs2: add dlm_query_join_request handler V2

[Jeff Liu]

this patch dissect the dlm_query_join_request message as follows,

Magic: Request (0xfa55)
    ...
    ..
    DLM Protocol: 1.0
    FS Protocol: 1.0
    Domain Name: A898D073F6244E9EBEB057B4F47EF61A
    Node Map: 0000001100000000000000000000000000000000000000000000000000000000
    Node Map: 0000000000000000000000000000000000000000000000000000000000000000
    Node Map: 0000000000000000000000000000000000000000000000000000000000000000
    Node Map: 0000000000000000000000000000000000000000000000000000000000000000

Signed-off-by: Jeff Liu <jeff.liu at oracle.com>
---
 epan/dissectors/packet-ocfs2.c |  106 ++++++++++++++++++++++++++++++++++++++-
 1 files changed, 103 insertions(+), 3 deletions(-)

diff --git a/epan/dissectors/packet-ocfs2.c b/epan/dissectors/packet-ocfs2.c
index ce57c3f..1523e22 100644
--- a/epan/dissectors/packet-ocfs2.c
+++ b/epan/dissectors/packet-ocfs2.c
@@ -776,13 +776,36 @@ struct dlm_master_requery {
 	guint32 pad3;
 	guint8 name[O2NM_MAX_NAME_LEN];
 };
-struct dlm_query_join_request
-{
+
+#define O2NM_MAX_NODES 255
+#define BITS_PER_BYTE 8
+#define BITS_TO_BYTES(bits) (((bits)+BITS_PER_BYTE-1)/BITS_PER_BYTE)
+
+/* dlm_query_join_request for ocfs2-1.2.x */
+struct dlm_query_join_request_129 {
 	guint8 node_idx;
 	guint8 pad1[2];	// unused
 	guint8 name_len;
 	guint8 domain[O2NM_MAX_NAME_LEN];
+	guint8 node_map[BITS_TO_BYTES(O2NM_MAX_NODES)];
+};
+
+struct dlm_protocol_version {
+	guint8 pv_major;
+	guint8 pv_minor;
+};
+
+/* the latest msg layout */
+struct dlm_query_join_request {
+	guint8 node_idx;
+	guint8 pad1[2];
+	guint8 name_len;
+	struct dlm_protocol_version dlm_proto;
+	struct dlm_protocol_version fs_proto;
+	guint8 domain[O2NM_MAX_NAME_LEN];
+	guint8 node_map[BITS_TO_BYTES(O2NM_MAX_NODES)];
 };
+
 struct dlm_assert_joined
 {
 	guint8 node_idx;
@@ -1148,6 +1171,79 @@ static void msg_struct_enumerate_fields(struct dlm_msg_struct_def *def, proto_tr
 	}
 }
 
+static void dissect_dlm_query_join_request(proto_tree *tree, tvbuff_t *tvb,
+					   int offset)
+{
+	proto_item *item;
+	guint8 cc, namelen;
+	guint8 node_bits_array[256];
+	guint8 node_map[BITS_TO_BYTES(O2NM_MAX_NODES)];
+	guint16 dlm_proto, fs_proto;
+	gint len;
+	char line[65];
+	int i, j;
+
+	proto_tree_add_item(tree, hf_dlm_node_idx, tvb, offset, 1, FALSE);
+
+	/* skip follow 2 padding bytes */
+	offset += 3;
+	namelen = tvb_get_guint8(tvb, offset);
+	proto_tree_add_item(tree, hf_dlm_namelen, tvb, offset, 1, FALSE);
+
+	++offset;
+	len = tvb_reported_length_remaining(tvb, offset);
+
+	/* if the left message length more than namelen + node_map length,
+	 * its most likely ocfs2-1.4 or newer message comming,
+	 * or else ocfs2-1.2 if equal to */
+	if (len == (sizeof(struct dlm_protocol_version) * 2 +
+		    O2NM_MAX_NAME_LEN +
+		    BITS_TO_BYTES(O2NM_MAX_NODES))) {
+		dlm_proto = tvb_get_ntohs(tvb, offset);
+		proto_tree_add_text(tree, tvb, offset, 2,
+				"DLM Protocol: %d.%d",
+				((dlm_proto >> 8) & 0xff),
+				(dlm_proto & 0xff));
+
+		offset += 2;
+		fs_proto = tvb_get_ntohs(tvb, offset);
+		proto_tree_add_text(tree, tvb, offset, 2,
+				"FS Protocol: %d.%d",
+				((fs_proto >> 8) & 0xff),
+				(fs_proto & 0xff));
+
+		offset += 2;
+		proto_tree_add_item(tree, hf_dlm_domain_name, tvb,
+				    offset, namelen, FALSE);
+	} else if (len == (O2NM_MAX_NAME_LEN + BITS_TO_BYTES(O2NM_MAX_NODES)))
+		proto_tree_add_item(tree, hf_dlm_domain_name, tvb,
+				    offset, namelen, FALSE);
+
+	offset += O2NM_MAX_NAME_LEN;
+	tvb_memcpy(tvb, node_map, offset, sizeof(node_map));
+
+	memset(node_bits_array, 0, sizeof(node_bits_array));
+	for (i = 0; i < sizeof(node_map); i++) {
+		cc = node_map[i];
+		for (j = 0; j < 8; j++)
+			node_bits_array[i * 8 + j] = (((cc >> j) & 1) ?
+							'1' : '0');
+	}
+
+	i = 0;
+	while (i < 256) {
+		memset(line, 0, sizeof(line));
+		/* line[65], the valid buf size is 64, the latest char
+		 * is used to cut off the string
+		 */
+		for (j = 0; j < (sizeof(line) - 1); j++)
+			line[j] = node_bits_array[i++];
+
+		item = proto_tree_add_text(tree, tvb, offset, 10, "Node Map: ");
+		proto_item_append_text(item, "%s", line);
+	}
+}
+
 static int dissect_ocfs2(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 {
 	proto_tree *subtree = NULL;
@@ -1240,13 +1336,17 @@ static int dissect_ocfs2(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 			}
 		}
 
-
 		if (magic == O2NET_MSG_MAGIC) {
 			struct dlm_msg_struct_def *def;
 			def = msg_struct_lookup_by_type(msg_type);
 			if (def)
 				msg_struct_enumerate_fields(def, subtree, tvb, O2NET_MSG_HDR_OFF_PAYLOAD);
 		}
+
+		if (msg_type == DLM_QUERY_JOIN_MSG)
+			if (magic == O2NET_MSG_MAGIC)
+				dissect_dlm_query_join_request(subtree,
+					tvb, O2NET_MSG_HDR_OFF_PAYLOAD);
 	}
 out:
 	return ret;
-- 
1.5.4.3