The beginning of an openflow dissector.

svn path=/trunk/; revision=50513

3 files changed, 947 insertions, 0 deletions

diff --git a/epan/CMakeLists.txt b/epan/CMakeLists.txt
index 1e33c1ae6e..f4b73b2138 100644
--- a/epan/CMakeLists.txt
+++ b/epan/CMakeLists.txt
@@ -973,6 +973,7 @@ set(DISSECTOR_SRC
 	dissectors/packet-olsr.c
 	dissectors/packet-omapi.c
 	dissectors/packet-omron-fins.c
+	dissectors/packet-openflow.c
 	dissectors/packet-opensafety.c
 	dissectors/packet-openvpn.c
 	dissectors/packet-openwire.c
diff --git a/epan/dissectors/Makefile.common b/epan/dissectors/Makefile.common
index 1ef599b232..0138a03180 100644
--- a/epan/dissectors/Makefile.common
+++ b/epan/dissectors/Makefile.common
@@ -900,6 +900,7 @@ DISSECTOR_SRC = \
 	packet-olsr.c		\
 	packet-omapi.c		\
 	packet-omron-fins.c	\
+	packet-openflow.c	\
 	packet-opensafety.c	\
 	packet-openvpn.c	\
 	packet-openwire.c	\
diff --git a/epan/dissectors/packet-openflow.c b/epan/dissectors/packet-openflow.c
new file mode 100644
index 0000000000..fa255a2f11
--- /dev/null
+++ b/epan/dissectors/packet-openflow.c
@@ -0,0 +1,945 @@
+/* packet-openflow.c
+ * Routines for OpenFlow dissection
+ * Copyright 2013, Anders Broman <anders.broman@ericsson.com>
+ *
+ * $Id$
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Ref https://www.opennetworking.org/sdn-resources/onf-specifications/openflow 
+ */
+
+#include "config.h"
+
+#include <glib.h>
+
+#include <epan/packet.h>
+#include <epan/prefs.h>
+
+void proto_reg_handoff_openflow(void);
+
+static int g_openflow_port = 0;
+
+/* Initialize the protocol and registered fields */
+static int proto_openflow = -1;
+static int hf_openflow_version = -1;
+static int hf_openflow_type = -1;
+static int hf_openflow_length = -1;
+static int hf_openflow_xid = -1;
+
+static int hf_openflow_datapath_id = -1;
+static int hf_openflow_datapath_mac = -1;
+static int hf_openflow_datapath_impl = -1;
+static int hf_openflow_n_buffers = -1;
+static int hf_openflow_n_tables = -1;
+static int hf_openflow_pad3 = -1;
+static int hf_openflow_capabilities = -1;
+static int hf_openflow_actions = -1;
+static int hf_openflow_reserved32 = -1;
+static int hf_openflow_cap_flow_stats = -1;
+static int hf_openflow_table_stats = -1;
+static int hf_openflow_port_stats = -1;
+static int hf_openflow_group_stats = -1;
+static int hf_openflow_ip_reasm = -1; 
+static int hf_openflow_queue_stats = -1;
+static int hf_openflow_port_blocked = -1;
+
+static int hf_openflow_output = -1; /* Output to switch port. */
+static int hf_openflow_set_vlan_vid = -1; /* Set the 802.1q VLAN id. */
+static int hf_openflow_set_vlan_pcp = -1; /* Set the 802.1q priority. */
+static int hf_openflow_strip_vlan = -1; /* Strip the 802.1q header. */
+static int hf_openflow_set_dl_src = -1; /* Ethernet source address. */
+static int hf_openflow_set_dl_dst = -1; /* Ethernet destination address. */
+static int hf_openflow_set_nw_src = -1; /* IP source address. */
+static int hf_openflow_set_nw_dst = -1; /* IP destination address. */
+static int hf_openflow_set_nw_tos = -1; /* IP ToS (DSCP field, 6 bits). */
+static int hf_openflow_set_tp_src = -1; /* TCP/UDP source port. */
+static int hf_openflow_set_tp_dst = -1; /* TCP/UDP destination port. */
+static int hf_openflow_enqueue = -1; /* Output to queue. */
+
+static int hf_openflow_port_no = -1;
+static int hf_openflow_hw_addr = -1;
+static int hf_openflow_port_name = -1;
+
+
+static int hf_openflow_port_config = -1;
+static int hf_openflow_port_state = -1;
+static int hf_openflow_port_curr = -1;
+static int hf_openflow_port_advertised = -1;
+static int hf_openflow_port_supported = -1;
+static int hf_openflow_port_peer = -1;
+
+static int hf_openflow_port_down = -1;    /* Port is administratively down. */
+static int hf_openflow_no_stp = -1;       /* Disable 802.1D spanning tree on port. */
+static int hf_openflow_no_recv = -1;      /* Drop all packets except 802.1D spanning tree packets. */
+static int hf_openflow_no_recv_stp = -1;  /* Drop received 802.1D STP packets. */
+static int hf_openflow_no_flood = -1;     /* Do not include this port when flooding. */
+static int hf_openflow_no_fwd = -1;       /* Drop packets forwarded to port. */
+static int hf_openflow_no_packet_in = -1; /* Do not send packet-in msgs for port. */
+
+static int hf_openflow_link_down = -1;    /* No physical link present. */
+static int hf_openflow_stp_listen = -1;   /* Not learning or relaying frames. */
+static int hf_openflow_stp_learn = -1;    /* Learning but not relaying frames. */
+static int hf_openflow_stp_forward = -1;  /* Learning and relaying frames. */
+static int hf_openflow_stp_block = -1;    /* Not part of spanning tree. */
+static int hf_openflow_stp_mask = -1;     /* Bit mask for OFPPS_STP_* values. */
+
+static int hf_openflow_10mb_hd = -1;      /* 10 Mb half-duplex rate support. */
+static int hf_openflow_10mb_fd = -1;      /* 10 Mb full-duplex rate support. */
+static int hf_openflow_100mb_hd = -1;     /* 100 Mb half-duplex rate support. */
+static int hf_openflow_100mb_fd = -1;     /* 100 Mb full-duplex rate support. */
+static int hf_openflow_1gb_hd = -1;       /* 1 Gb half-duplex rate support. */
+static int hf_openflow_1gb_fd = -1;       /* 1 Gb full-duplex rate support. */
+static int hf_openflow_10gb_fd = -1;      /* 10 Gb full-duplex rate support. */
+static int hf_openflow_copper = -1;       /* Copper medium. */
+static int hf_openflow_fiber = -1;        /* Fiber medium. */
+static int hf_openflow_autoneg = -1;      /* Auto-negotiation. */
+static int hf_openflow_pause = -1;        /* Pause. */
+static int hf_openflow_pause_asym = -1;   /* Asymmetric pause. */
+
+/* Initialize the subtree pointers */
+static gint ett_openflow = -1;
+static gint ett_openflow_path_id = -1;
+static gint ett_openflow_cap = -1;
+static gint ett_openflow_act = -1;
+static gint ett_openflow_port = -1;
+static gint ett_openflow_port_cnf = -1;
+static gint ett_openflow_port_state = -1;
+static gint ett_port_cf = -1;
+
+
+static const value_string openflow_version_values[] = {
+    { 0x01, "1.0" },
+    { 0x02, "1.1" },
+    { 0x03, "1.2" },
+    { 0x04, "1.3" },
+    { 0, NULL }
+};
+
+/* Immutable messages. */
+#define OFPT_HELLO                     0 /* Symmetric message */
+#define OFPT_ERROR                     1 /* Symmetric message */
+#define OFPT_ECHO_REQUEST              2 /* Symmetric message */
+#define OFPT_ECHO_REPLY                3 /* Symmetric message */
+#define OFPT_EXPERIMENTER              4 /* Symmetric message */
+/* Switch configuration messages. */
+#define OFPT_FEATURES_REQUEST          5 /* Controller/switch message */
+#define OFPT_FEATURES_REPLY            6 /* Controller/switch message */
+#define OFPT_GET_CONFIG_REQUEST        7 /* Controller/switch message */
+#define OFPT_GET_CONFIG_REPLY          8 /* Controller/switch message */
+#define OFPT_SET_CONFIG                9 /* Controller/switch message */
+/* Asynchronous messages. */
+#define OFPT_PACKET_IN                10 /* Async message */
+#define OFPT_FLOW_REMOVED             11 /* Async message */
+#define OFPT_PORT_STATUS              12 /* Async message */
+/* Controller command messages. */
+#define OFPT_PACKET_OUT               13 /* Controller/switch message */
+#define OFPT_FLOW_MOD                 14 /* Controller/switch message */
+#define OFPT_GROUP_MOD                15 /* Controller/switch message */
+#define OFPT_PORT_MOD                 16 /* Controller/switch message */
+#define OFPT_TABLE_MOD                17 /* Controller/switch message */
+/* Multipart messages. */
+#define OFPT_MULTIPART_REQUEST        18 /* Controller/switch message */
+#define OFPT_MULTIPART_REPLY          19 /* Controller/switch message */
+/* Barrier messages. */
+#define OFPT_BARRIER_REQUEST          20 /* Controller/switch message */
+#define OFPT_BARRIER_REPLY            21 /* Controller/switch message */
+/* Queue Configuration messages. */
+#define OFPT_QUEUE_GET_CONFIG_REQUEST 22 /* Controller/switch message */
+#define OFPT_QUEUE_GET_CONFIG_REPLY   23 /* Controller/switch message */
+/* Controller role change request messages. */
+#define OFPT_ROLE_REQUEST             24 /* Controller/switch message */
+#define OFPT_ROLE_REPLY               25 /* Controller/switch message */
+/* Asynchronous message configuration. */
+#define OFPT_GET_ASYNC_REQUEST        26 /* Controller/switch message */
+#define OFPT_GET_ASYNC_REPLY          27 /* Controller/switch message */
+#define OFPT_SET_ASYNC                28 /* Controller/switch message */
+/* Meters and rate limiters configuration messages. */
+#define OFPT_METER_MOD                29 /* Controller/switch message */
+
+static const value_string openflow_type_values[] = {
+/* Immutable messages. */
+    { 0, "OFPT_HELLO" },              /* Symmetric message */
+    { 1, "OFPT_ERROR" },              /* Symmetric message */
+    { 2, "OFPT_ECHO_REQUEST" },       /* Symmetric message */
+    { 3, "OFPT_ECHO_REPLY" },         /* Symmetric message */
+    { 4, "OFPT_EXPERIMENTER" },       /* Symmetric message */
+/* Switch configuration messages. */
+    { 5, "OFPT_FEATURES_REQUEST" },   /* Controller/switch message */
+    { 6, "OFPT_FEATURES_REPLY" },     /* Controller/switch message */
+    { 7, "OFPT_GET_CONFIG_REQUEST" }, /* Controller/switch message */
+    { 8, "OFPT_GET_CONFIG_REPLY" },   /* Controller/switch message */
+    { 9, "OFPT_SET_CONFIG" },         /* Controller/switch message */
+/* Asynchronous messages. */
+    { 10, "OFPT_PACKET_IN" },                /* Async message */
+    { 11, "OFPT_FLOW_REMOVED" },             /* Async message */
+    { 12, "OFPT_PORT_STATUS" },              /* Async message */
+/* Controller command messages. */
+    { 13, "OFPT_PACKET_OUT" },               /* Controller/switch message */
+    { 14, "OFPT_FLOW_MOD" },                 /* Controller/switch message */
+    { 15, "OFPT_GROUP_MOD" },                /* Controller/switch message */
+    { 16, "OFPT_PORT_MOD" },                 /* Controller/switch message */
+    { 17, "OFPT_TABLE_MOD" },                /* Controller/switch message */
+/* Multipart messages. */
+    { 18, "OFPT_MULTIPART_REQUEST" },        /* Controller/switch message */
+    { 19, "OFPT_MULTIPART_REPLY" },          /* Controller/switch message */
+/* Barrier messages. */
+    { 20, "OFPT_BARRIER_REQUEST" },          /* Controller/switch message */
+    { 21, "OFPT_BARRIER_REPLY" },            /* Controller/switch message */
+/* Queue Configuration messages. */
+    { 22, "OFPT_QUEUE_GET_CONFIG_REQUEST" }, /* Controller/switch message */
+    { 23, "OFPT_QUEUE_GET_CONFIG_REPLY" },   /* Controller/switch message */
+/* Controller role change request messages. */
+    { 24, "OFPT_ROLE_REQUEST" },             /* Controller/switch message */
+    { 25, "OFPT_ROLE_REPLY" },               /* Controller/switch message */
+/* Asynchronous message configuration. */
+    { 26, "OFPT_GET_ASYNC_REQUEST" },        /* Controller/switch message */
+    { 27, "OFPT_GET_ASYNC_REPLY" },          /* Controller/switch message */
+    { 28, "OFPT_SET_ASYNC" },                /* Controller/switch message */
+/* Meters and rate limiters configuration messages. */
+    { 29, "OFPT_METER_MOD" },                /* Controller/switch message */
+    { 0, NULL }
+};
+
+#define OFPC_FLOW_STATS   1<<0  /* Flow statistics. */
+#define OFPC_TABLE_STATS  1<<1  /* Table statistics. */
+#define OFPC_PORT_STATS   1<<2  /* Port statistics. */
+#define OFPC_GROUP_STATS  1<<3  /* Group statistics. */
+#define OFPC_IP_REASM     1<<5  /* Can reassemble IP fragments. */
+#define OFPC_QUEUE_STATS  1<<6  /* Queue statistics. */
+#define OFPC_PORT_BLOCKED 1<<8  /* Switch will block looping ports. */
+
+#define OFPAT_OUTPUT_MASK       1<<0  /* Output to switch port. */
+#define OFPAT_SET_VLAN_VID_MASK 1<<1  /* Set the 802.1q VLAN id. */
+#define OFPAT_SET_VLAN_PCP_MASK 1<<2  /* Set the 802.1q priority. */
+#define OFPAT_STRIP_VLAN_MASK   1<<3  /* Strip the 802.1q header. */
+#define OFPAT_SET_DL_SRC_MASK   1<<4  /* Ethernet source address. */
+#define OFPAT_SET_DL_DST_MASK   1<<5  /* Ethernet destination address. */
+#define OFPAT_SET_NW_SRC_MASK   1<<6  /* IP source address. */
+#define OFPAT_SET_NW_DST_MASK   1<<7  /* IP destination address. */
+#define OFPAT_SET_NW_TOS_MASK   1<<8  /* IP ToS (DSCP field, 6 bits). */
+#define OFPAT_SET_TP_SRC_MASK   1<<9  /* TCP/UDP source port. */
+#define OFPAT_SET_TP_DST_MASK   1<<10 /* TCP/UDP destination port. */
+#define OFPAT_ENQUEUE_MASK      1<<11 /* Output to queue. */
+
+#define OFPPC_PORT_DOWN    1<<0 /* Port is administratively down. */
+#define OFPPC_NO_STP       1<<1 /* Disable 802.1D spanning tree on port. */
+#define OFPPC_NO_RECV      1<<2 /* Drop all packets except 802.1D spanning tree packets. */
+#define OFPPC_NO_RECV_STP  1<<3 /* Drop received 802.1D STP packets. */
+#define OFPPC_NO_FLOOD     1<<4 /* Do not include this port when flooding. */
+#define OFPPC_NO_FWD       1<<5 /* Drop packets forwarded to port. */
+#define OFPPC_NO_PACKET_IN 1<<6 /* Do not send packet-in msgs for port. */
+
+#define OFP_MAX_PORT_NAME_LEN 16
+
+#define OFPPS_LINK_DOWN    1<<0 /* No physical link present. */
+#define OFPPS_STP_LISTEN   0<<8 /* Not learning or relaying frames. */
+#define OFPPS_STP_LEARN    1<<8 /* Learning but not relaying frames. */
+#define OFPPS_STP_FORWARD  2<<8 /* Learning and relaying frames. */
+#define OFPPS_STP_BLOCK    3<<8 /* Not part of spanning tree. */
+#define OFPPS_STP_MASK     3<<8 /* Bit mask for OFPPS_STP_* values. */
+
+
+#define OFPPF_10MB_HD      1<<0 /* 10 Mb half-duplex rate support. */
+#define OFPPF_10MB_FD      1<<1 /* 10 Mb full-duplex rate support. */
+#define OFPPF_100MB_HD     1<<2 /* 100 Mb half-duplex rate support. */
+#define OFPPF_100MB_FD     1<<3 /* 100 Mb full-duplex rate support. */
+#define OFPPF_1GB_HD       1<<4 /* 1 Gb half-duplex rate support. */
+#define OFPPF_1GB_FD       1<<5 /* 1 Gb full-duplex rate support. */
+#define OFPPF_10GB_FD      1<<6 /* 10 Gb full-duplex rate support. */
+#define OFPPF_COPPER       1<<7 /* Copper medium. */
+#define OFPPF_FIBER        1<<8 /* Fiber medium. */
+#define OFPPF_AUTONEG      1<<9 /* Auto-negotiation. */
+#define OFPPF_PAUSE        1<<10 /* Pause. */
+#define OFPPF_PAUSE_ASYM   1<<11 /* Asymmetric pause. */
+
+static void
+dissect_openflow_phy_port(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset)
+{
+    proto_item *ti;
+    proto_tree *port_cnf_tree, *port_state_tree, *port_cf_tree;
+
+    proto_tree_add_item(tree, hf_openflow_port_no, tvb, offset, 2, ENC_BIG_ENDIAN);
+    offset+=2;
+    proto_tree_add_item(tree, hf_openflow_hw_addr, tvb, offset, 6, ENC_BIG_ENDIAN);
+    offset+=6;
+    proto_tree_add_item(tree, hf_openflow_port_name, tvb, offset, OFP_MAX_PORT_NAME_LEN, ENC_BIG_ENDIAN);
+    offset+=OFP_MAX_PORT_NAME_LEN;
+
+    /* Bitmap of OFPPC_* flags. */
+    ti = proto_tree_add_item(tree, hf_openflow_port_config, tvb, offset, 4, ENC_BIG_ENDIAN);
+    port_cnf_tree = proto_item_add_subtree(ti, ett_openflow_port_cnf);
+
+    /* Port is administratively down. */
+    proto_tree_add_item(port_cnf_tree, hf_openflow_port_down, tvb, offset, 4, ENC_BIG_ENDIAN);
+    /* Disable 802.1D spanning tree on port. */
+    proto_tree_add_item(port_cnf_tree, hf_openflow_no_stp, tvb, offset, 4, ENC_BIG_ENDIAN);
+    /* Drop all packets except 802.1D spanning tree packets. */
+    proto_tree_add_item(port_cnf_tree, hf_openflow_no_recv, tvb, offset, 4, ENC_BIG_ENDIAN);
+    /* Drop received 802.1D STP packets. */
+    proto_tree_add_item(port_cnf_tree, hf_openflow_no_recv_stp, tvb, offset, 4, ENC_BIG_ENDIAN);
+    /* Do not include this port when flooding. */
+    proto_tree_add_item(port_cnf_tree, hf_openflow_no_flood, tvb, offset, 4, ENC_BIG_ENDIAN);
+     /* Drop packets forwarded to port. */
+    proto_tree_add_item(port_cnf_tree, hf_openflow_no_fwd, tvb, offset, 4, ENC_BIG_ENDIAN);
+    /* Do not send packet-in msgs for port. */
+    proto_tree_add_item(port_cnf_tree, hf_openflow_no_packet_in, tvb, offset, 4, ENC_BIG_ENDIAN);
+    offset+=4;
+
+    /* Bitmap of OFPPS_* flags. */
+    ti = proto_tree_add_item(tree, hf_openflow_port_state, tvb, offset, 4, ENC_BIG_ENDIAN);
+    port_state_tree = proto_item_add_subtree(ti, ett_openflow_port_state);
+
+    /* No physical link present. */
+    proto_tree_add_item(port_cnf_tree, hf_openflow_link_down, tvb, offset, 4, ENC_BIG_ENDIAN);
+    /* Not learning or relaying frames. */
+    proto_tree_add_item(port_cnf_tree, hf_openflow_stp_listen, tvb, offset, 4, ENC_BIG_ENDIAN);
+    /* Learning but not relaying frames. */
+    proto_tree_add_item(port_cnf_tree, hf_openflow_stp_learn, tvb, offset, 4, ENC_BIG_ENDIAN);
+    /* Learning and relaying frames. */
+    proto_tree_add_item(port_cnf_tree, hf_openflow_stp_forward, tvb, offset, 4, ENC_BIG_ENDIAN);
+    /* Not part of spanning tree. */
+    proto_tree_add_item(port_cnf_tree, hf_openflow_stp_block, tvb, offset, 4, ENC_BIG_ENDIAN);
+    /* Bit mask for OFPPS_STP_* values. */
+    proto_tree_add_item(port_cnf_tree, hf_openflow_stp_mask, tvb, offset, 4, ENC_BIG_ENDIAN);
+
+    offset+=4;
+
+    /* Current features. */
+    ti = proto_tree_add_item(tree, hf_openflow_port_curr, tvb, offset, 4, ENC_BIG_ENDIAN);
+    port_cf_tree = proto_item_add_subtree(ti, ett_port_cf);
+	/* 10 Mb half-duplex rate support. */
+    proto_tree_add_item(port_cf_tree, hf_openflow_10mb_hd, tvb, offset, 4, ENC_BIG_ENDIAN);
+	/* 10 Mb full-duplex rate support. */
+    proto_tree_add_item(port_cf_tree, hf_openflow_10mb_fd, tvb, offset, 4, ENC_BIG_ENDIAN);
+	/* 100 Mb half-duplex rate support. */
+    proto_tree_add_item(port_cf_tree, hf_openflow_100mb_hd, tvb, offset, 4, ENC_BIG_ENDIAN);
+	/* 100 Mb full-duplex rate support. */
+    proto_tree_add_item(port_cf_tree, hf_openflow_100mb_fd, tvb, offset, 4, ENC_BIG_ENDIAN);
+	/* 1 Gb half-duplex rate support. */
+    proto_tree_add_item(port_cf_tree, hf_openflow_1gb_hd, tvb, offset, 4, ENC_BIG_ENDIAN);
+	/* 1 Gb full-duplex rate support. */
+    proto_tree_add_item(port_cf_tree, hf_openflow_1gb_fd, tvb, offset, 4, ENC_BIG_ENDIAN);
+	/* 10 Gb full-duplex rate support. */
+    proto_tree_add_item(port_cf_tree, hf_openflow_10gb_fd, tvb, offset, 4, ENC_BIG_ENDIAN);
+	/* Copper medium. */
+    proto_tree_add_item(port_cf_tree, hf_openflow_copper, tvb, offset, 4, ENC_BIG_ENDIAN);
+	/* Fiber medium. */
+    proto_tree_add_item(port_cf_tree, hf_openflow_fiber, tvb, offset, 4, ENC_BIG_ENDIAN);
+	/* Auto-negotiation. */
+    proto_tree_add_item(port_cf_tree, hf_openflow_autoneg, tvb, offset, 4, ENC_BIG_ENDIAN);
+	/* Pause. */
+    proto_tree_add_item(port_cf_tree, hf_openflow_pause, tvb, offset, 4, ENC_BIG_ENDIAN);
+	/* Asymmetric pause. */
+    proto_tree_add_item(port_cf_tree, hf_openflow_pause_asym, tvb, offset, 4, ENC_BIG_ENDIAN);
+    offset+=4;
+
+    /* Features being advertised by the port. */
+    proto_tree_add_item(tree, hf_openflow_port_advertised, tvb, offset, 4, ENC_BIG_ENDIAN);
+    offset+=4;
+
+    /* Features supported by the port. */
+    proto_tree_add_item(tree, hf_openflow_port_supported, tvb, offset, 4, ENC_BIG_ENDIAN);
+    offset+=4;
+    /* Features advertised by peer. */
+    proto_tree_add_item(tree, hf_openflow_port_peer, tvb, offset, 4, ENC_BIG_ENDIAN);
+
+
+}
+/* 
+ * Switch features. 
+ *
+   struct ofp_switch_features {
+   struct ofp_header header;
+   uint64_t datapath_id; * Datapath unique ID. The lower 48-bits are for
+                           a MAC address, while the upper 16-bits are
+                           implementer-defined. *
+   uint32_t n_buffers;   * Max packets buffered at once. *
+   uint8_t n_tables;     * Number of tables supported by datapath. *
+   uint8_t pad[3];       * Align to 64-bits. *
+* Features. *
+   uint32_t capabilities;  * Bitmap of support "ofp_capabilities".   *
+   uptill 1.1
+       uint32_t actions;       * Bitmap of supported "ofp_action_type"s. *
+   from 1.2
+       uint32_t reserved;
+* Port info.*
+  struct ofp_phy_port ports[0]; * Port definitions. The number of ports
+                                  is inferred from the length field in
+                                  the header.
+  };
+*/
+static void
+dissect_openflow_features_reply(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, guint8 version, guint16 length)
+{
+    proto_item *ti;
+    proto_tree *path_id_tree, *cap_tree, *act_tree;
+
+    guint16 length_remaining;
+    
+    ti = proto_tree_add_item(tree, hf_openflow_datapath_id, tvb, offset, 8, ENC_BIG_ENDIAN);
+    path_id_tree = proto_item_add_subtree(ti, ett_openflow_path_id);
+    proto_tree_add_item(path_id_tree, hf_openflow_datapath_mac, tvb, offset, 6, ENC_BIG_ENDIAN);
+    offset+=6;
+    proto_tree_add_item(path_id_tree, hf_openflow_datapath_impl, tvb, offset, 2, ENC_BIG_ENDIAN);
+    offset+=2;
+
+    proto_tree_add_item(tree, hf_openflow_n_buffers, tvb, offset, 4, ENC_BIG_ENDIAN);
+    offset+=4;
+
+    proto_tree_add_item(tree, hf_openflow_n_tables, tvb, offset, 1, ENC_BIG_ENDIAN);
+    offset++;
+
+    if(version<3){
+        proto_tree_add_item(tree, hf_openflow_pad3, tvb, offset, 3, ENC_BIG_ENDIAN);
+        offset+=3;
+    }else{
+    }
+
+    ti = proto_tree_add_item(tree, hf_openflow_capabilities, tvb, offset, 4, ENC_BIG_ENDIAN);
+    cap_tree = proto_item_add_subtree(ti, ett_openflow_cap);
+
+    /* Dissect flags */
+    proto_tree_add_item(cap_tree, hf_openflow_cap_flow_stats, tvb, offset, 4, ENC_BIG_ENDIAN);
+    proto_tree_add_item(cap_tree, hf_openflow_table_stats,    tvb, offset, 4, ENC_BIG_ENDIAN);
+    proto_tree_add_item(cap_tree, hf_openflow_port_stats,     tvb, offset, 4, ENC_BIG_ENDIAN);
+    proto_tree_add_item(cap_tree, hf_openflow_group_stats,    tvb, offset, 4, ENC_BIG_ENDIAN);
+    proto_tree_add_item(cap_tree, hf_openflow_ip_reasm,       tvb, offset, 4, ENC_BIG_ENDIAN);
+    proto_tree_add_item(cap_tree, hf_openflow_queue_stats,    tvb, offset, 4, ENC_BIG_ENDIAN);
+    proto_tree_add_item(cap_tree, hf_openflow_port_blocked,   tvb, offset, 4, ENC_BIG_ENDIAN);
+    offset+=4;
+
+    if(version<2){
+        ti = proto_tree_add_item(tree, hf_openflow_actions, tvb, offset, 4, ENC_BIG_ENDIAN);
+        act_tree = proto_item_add_subtree(ti, ett_openflow_act);
+        /* Dissect flags */
+        proto_tree_add_item(act_tree, hf_openflow_output, tvb, offset, 4, ENC_BIG_ENDIAN);
+        proto_tree_add_item(act_tree, hf_openflow_set_vlan_vid, tvb, offset, 4, ENC_BIG_ENDIAN);
+        proto_tree_add_item(act_tree, hf_openflow_set_vlan_pcp, tvb, offset, 4, ENC_BIG_ENDIAN);
+        proto_tree_add_item(act_tree, hf_openflow_strip_vlan, tvb, offset, 4, ENC_BIG_ENDIAN);
+        proto_tree_add_item(act_tree, hf_openflow_set_dl_src, tvb, offset, 4, ENC_BIG_ENDIAN);
+        proto_tree_add_item(act_tree, hf_openflow_set_dl_dst, tvb, offset, 4, ENC_BIG_ENDIAN);
+        proto_tree_add_item(act_tree, hf_openflow_set_nw_src, tvb, offset, 4, ENC_BIG_ENDIAN);
+        proto_tree_add_item(act_tree, hf_openflow_set_nw_dst, tvb, offset, 4, ENC_BIG_ENDIAN);
+        proto_tree_add_item(act_tree, hf_openflow_set_nw_tos, tvb, offset, 4, ENC_BIG_ENDIAN);
+        proto_tree_add_item(act_tree, hf_openflow_set_tp_src, tvb, offset, 4, ENC_BIG_ENDIAN);
+        proto_tree_add_item(act_tree, hf_openflow_set_tp_dst, tvb, offset, 4, ENC_BIG_ENDIAN);
+        proto_tree_add_item(act_tree, hf_openflow_enqueue, tvb, offset, 4, ENC_BIG_ENDIAN);
+    }else{
+        proto_tree_add_item(tree, hf_openflow_reserved32, tvb, offset, 4, ENC_BIG_ENDIAN);
+    }
+    offset+=4;
+    
+    length_remaining = length-32;
+    if(length_remaining > 0){
+        guint16 num_ports = length_remaining/48;
+        int i;
+        if ((length_remaining&0x003f) != 0){
+            /* protocol_error */
+        }
+        for(i=0; i<num_ports ;i++){
+            proto_tree *port_tree;
+
+            ti = proto_tree_add_text(tree, tvb, offset, 48, "Port data %u",i+1);
+            port_tree = proto_item_add_subtree(ti, ett_openflow_port);
+            dissect_openflow_phy_port(tvb, pinfo, port_tree, offset);
+            offset+=48;
+        }
+    }
+
+}
+/* Code to actually dissect the packets */
+static int
+dissect_openflow(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
+{
+    proto_item *ti;
+    proto_tree *openflow_tree;
+    guint offset = 0;
+    guint8 type, version;
+    guint16 length;
+
+
+    version = tvb_get_guint8(tvb, 0);
+    type    = tvb_get_guint8(tvb, 1);
+    /* Set the Protocol column to the constant string of openflow */
+    col_set_str(pinfo->cinfo, COL_PROTOCOL, "OpenFlow");
+    col_clear(pinfo->cinfo,COL_INFO);
+
+    if((version&0x80)==0x80){
+        col_set_str(pinfo->cinfo, COL_PROTOCOL, "OpenFlow experimental version");
+        proto_tree_add_text(tree, tvb, offset, -1, "Experimental versions not dissected");
+    }else{
+        version = version & 0x7f;
+        col_set_str(pinfo->cinfo, COL_PROTOCOL, "OpenFlow");
+        col_append_fstr(pinfo->cinfo, COL_INFO, "Type: %s",
+                  val_to_str_const(type, openflow_type_values, "Unknown Messagetype"));
+    }
+
+    /* Create display subtree for the protocol */
+    ti = proto_tree_add_item(tree, proto_openflow, tvb, 0, -1, ENC_NA);
+    openflow_tree = proto_item_add_subtree(ti, ett_openflow);
+
+    /* A.1 OpenFlow Header. */
+    /* OFP_VERSION. */
+    proto_tree_add_item(openflow_tree, hf_openflow_version, tvb, offset, 1, ENC_BIG_ENDIAN);
+    offset++;
+
+    /* One of the OFPT_ constants. */
+    proto_tree_add_item(openflow_tree, hf_openflow_type, tvb, offset, 1, ENC_BIG_ENDIAN);
+    offset++;
+
+    /* Length including this ofp_header. */
+    length = tvb_get_ntohs(tvb, offset);
+    proto_tree_add_item(openflow_tree, hf_openflow_length, tvb, offset, 2, ENC_BIG_ENDIAN);
+    offset+=2;
+
+    /* Transaction id associated with this packet. Replies use the same id as was in the request
+     * to facilitate pairing. 
+     */
+    proto_tree_add_item(openflow_tree, hf_openflow_xid, tvb, offset, 4, ENC_BIG_ENDIAN);
+    offset+=4;
+
+    switch(type){
+    case OFPT_HELLO:
+        /* 5.5.1 Hello
+         * The OFPT_HELLO message has no body;
+         */
+        break;
+    case OFPT_FEATURES_REQUEST:
+        /* 5.3.1 Handshake
+         * Upon TLS session establishment, the controller sends an OFPT_FEATURES_REQUEST
+         * message. This message does not contain a body beyond the OpenFlow header.
+         */
+        break;
+    case OFPT_FEATURES_REPLY:
+        dissect_openflow_features_reply(tvb, pinfo, openflow_tree, offset, version, length);
+        break;
+    default:
+        if(length>8){
+            proto_tree_add_text(tree, tvb, offset, -1, "Message data not dissected yet");
+        }
+        break;
+    }
+
+    return tvb_length(tvb);
+}
+
+/* Register the protocol with Wireshark.
+ *
+ * This format is require because a script is used to build the C function that
+ * calls all the protocol registration.
+ */
+void
+proto_register_openflow(void)
+{
+    module_t *openflow_module;
+
+    static hf_register_info hf[] = {
+        { &hf_openflow_version,
+            { "Version", "openflow.version",
+               FT_UINT8, BASE_HEX, VALS(openflow_version_values), 0x7f,
+               NULL, HFILL }
+        },
+        { &hf_openflow_type,
+            { "Type", "openflow.type",
+               FT_UINT8, BASE_DEC, VALS(openflow_type_values), 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_xid,
+            { "Transaction ID", "openflow.xid",
+               FT_UINT32, BASE_DEC, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_length,
+            { "Length", "openflow.length",
+               FT_UINT16, BASE_DEC, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_datapath_id,
+            { "Datapath unique ID", "openflow.datapath_id",
+               FT_UINT64, BASE_HEX, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_datapath_mac,
+            { "MAC addr", "openflow.datapath_mac",
+               FT_ETHER, BASE_NONE, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_datapath_impl,
+            { "Implementers part", "openflow.datapath_imp",
+               FT_UINT16, BASE_HEX, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_n_buffers,
+            { "n_buffers", "openflow.n_buffers",
+               FT_UINT32, BASE_DEC, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_n_tables,
+            { "n_tables", "openflow.n_tables",
+               FT_UINT8, BASE_DEC, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_pad3,
+            { "Padding", "openflow.pad3",
+               FT_UINT24, BASE_DEC, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_capabilities,
+            { "capabilities", "openflow.capabilities",
+               FT_UINT32, BASE_HEX, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_actions,
+            { "actions", "openflow.actions",
+               FT_UINT32, BASE_HEX, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_reserved32,
+            { "Reserved", "openflow.reserved32",
+               FT_UINT32, BASE_DEC, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_cap_flow_stats,
+            { "Flow statistics", "openflow.flow_stats",
+               FT_BOOLEAN, 32, NULL, OFPC_FLOW_STATS,
+               NULL, HFILL }
+        },
+        { &hf_openflow_table_stats,
+            { "Table statistics", "openflow.table_stats",
+               FT_BOOLEAN, 32, NULL, OFPC_TABLE_STATS,
+               NULL, HFILL }
+        },
+        { &hf_openflow_port_stats,
+            { "Port statistics", "openflow.port_stats",
+               FT_BOOLEAN, 32, NULL,  OFPC_PORT_STATS,
+               NULL, HFILL }
+        },
+        { &hf_openflow_group_stats,
+            { "Group statistics", "openflow.group_stats",
+               FT_BOOLEAN, 32, NULL, OFPC_GROUP_STATS,
+               NULL, HFILL }
+        },
+        { &hf_openflow_ip_reasm,
+            { "Can reassemble IP fragments", "openflow.ip_reasm",
+               FT_BOOLEAN, 32, NULL, OFPC_IP_REASM,
+               NULL, HFILL }
+        },
+        { &hf_openflow_queue_stats,
+            { "Queue statistics", "openflow.queue_stats",
+               FT_BOOLEAN, 32, NULL, OFPC_QUEUE_STATS,
+               NULL, HFILL }
+        },
+        { &hf_openflow_port_blocked,
+            { "Switch will block looping ports", "openflow.port_blocked",
+               FT_BOOLEAN, 32, NULL, OFPC_PORT_BLOCKED,
+               NULL, HFILL }
+        },
+        { &hf_openflow_output,
+            { "Output to switch port", "openflow.output",
+               FT_BOOLEAN, 32, NULL, OFPAT_OUTPUT_MASK,
+               NULL, HFILL }
+        },
+        { &hf_openflow_set_vlan_vid,
+            { "Set the 802.1q VLAN id", "openflow.set_vlan_vid",
+               FT_BOOLEAN, 32, NULL, OFPAT_SET_VLAN_VID_MASK,
+               NULL, HFILL }
+        },
+        { &hf_openflow_set_vlan_pcp,
+            { "Set the 802.1q priority", "openflow.set_vlan_pcp",
+               FT_BOOLEAN, 32, NULL, OFPAT_SET_VLAN_PCP_MASK,
+               NULL, HFILL }
+        },
+        { &hf_openflow_strip_vlan,
+            { "Strip the 802.1q header", "openflow.strip_vlan",
+               FT_BOOLEAN, 32, NULL, OFPAT_STRIP_VLAN_MASK,
+               NULL, HFILL }
+        },
+        { &hf_openflow_set_dl_src,
+            { "Ethernet source address", "openflow.set_dl_src",
+               FT_BOOLEAN, 32, NULL, OFPAT_SET_DL_SRC_MASK,
+               NULL, HFILL }
+        },
+        { &hf_openflow_set_dl_dst,
+            { "Ethernet destination address", "openflow.set_dl_ds",
+               FT_BOOLEAN, 32, NULL, OFPAT_SET_DL_DST_MASK,
+               NULL, HFILL }
+        },
+        { &hf_openflow_set_nw_src,
+            { "IP source address", "openflow.set_nw_src",
+               FT_BOOLEAN, 32, NULL, OFPAT_SET_NW_SRC_MASK,
+               NULL, HFILL }
+        },
+        { &hf_openflow_set_nw_dst,
+            { "IP destination address", "openflow.set_nw_ds",
+               FT_BOOLEAN, 32, NULL, OFPAT_SET_NW_DST_MASK,
+               NULL, HFILL }
+        },
+        { &hf_openflow_set_nw_tos,
+            { "IP ToS (DSCP field, 6 bits)", "openflow.set_nw_tos",
+               FT_BOOLEAN, 32, NULL, OFPAT_SET_NW_TOS_MASK,
+               NULL, HFILL }
+        },
+        { &hf_openflow_set_tp_src,
+            { "TCP/UDP source port", "openflow.set_tp_src",
+               FT_BOOLEAN, 32, NULL, OFPAT_SET_TP_SRC_MASK,
+               NULL, HFILL }
+        },
+        { &hf_openflow_set_tp_dst,
+            { "TCP/UDP destination port", "openflow.set_tp_dst",
+               FT_BOOLEAN, 32, NULL, OFPAT_SET_TP_DST_MASK,
+               NULL, HFILL }
+        },
+        { &hf_openflow_enqueue,
+            { "Output to queue", "openflow.enqueue",
+               FT_BOOLEAN, 32, NULL, OFPAT_ENQUEUE_MASK,
+               NULL, HFILL }
+        },
+        { &hf_openflow_port_no,
+            { "Port number", "openflow.port_no",
+               FT_UINT16, BASE_DEC, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_hw_addr,
+            { "HW Address", "openflow.hw_add",
+               FT_ETHER, BASE_NONE, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_port_name,
+            { "Name", "openflow.hw_add",
+               FT_STRING, BASE_NONE, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_port_config,
+            { "Config flags", "openflow.port_config",
+               FT_UINT32, BASE_HEX, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_port_state,
+            { "State flags", "openflow.port_state",
+               FT_UINT32, BASE_HEX, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_port_curr,
+            { "Current features", "openflow.port_curr",
+               FT_UINT32, BASE_HEX, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_port_advertised,
+            { "Advertised features", "openflow.port_advertised",
+               FT_UINT32, BASE_HEX, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_port_supported,
+            { "Features supported", "openflow.port_supported",
+               FT_UINT32, BASE_HEX, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_port_peer,
+            { "Features advertised by peer", "openflow.port_peer",
+               FT_UINT32, BASE_HEX, NULL, 0x0,
+               NULL, HFILL }
+        },
+        { &hf_openflow_port_down,
+            { "Port is administratively down", "openflow.port_down",
+               FT_BOOLEAN, 32, NULL, OFPPC_PORT_DOWN,
+               NULL, HFILL }
+        },
+        { &hf_openflow_no_stp,
+            { "Disable 802.1D spanning tree on port", "openflow.no_stp",
+               FT_BOOLEAN, 32, NULL, OFPPC_NO_STP,
+               NULL, HFILL }
+        },
+        { &hf_openflow_no_recv,
+            { "Drop all packets except 802.1D spanning tree packets", "openflow.no_recv",
+               FT_BOOLEAN, 32, NULL, OFPPC_NO_RECV,
+               NULL, HFILL }
+        },
+        { &hf_openflow_no_recv_stp,
+            { "Drop received 802.1D STP packets", "openflow.no_recv",
+               FT_BOOLEAN, 32, NULL, OFPPC_NO_RECV_STP,
+               NULL, HFILL }
+        },
+        { &hf_openflow_no_flood,
+            { "Do not include this port when flooding", "openflow.no_flood",
+               FT_BOOLEAN, 32, NULL, OFPPC_NO_FLOOD,
+               NULL, HFILL }
+        },
+        { &hf_openflow_no_fwd,
+            { "Drop packets forwarded to port", "openflow.no_fwd",
+               FT_BOOLEAN, 32, NULL, OFPPC_NO_FWD,
+               NULL, HFILL }
+        },
+        { &hf_openflow_no_packet_in,
+            { "Do not send packet-in msgs for port", "openflow.no_packet_in",
+               FT_BOOLEAN, 32, NULL, OFPPC_NO_PACKET_IN,
+               NULL, HFILL }
+        },
+        { &hf_openflow_link_down,
+            { "No physical link present", "openflow.link_down",
+               FT_BOOLEAN, 32, NULL, OFPPS_LINK_DOWN,
+               NULL, HFILL }
+        },
+        { &hf_openflow_stp_listen,
+            { "Not learning or relaying frames", "openflow.stp_listen",
+               FT_BOOLEAN, 32, NULL, OFPPS_STP_LISTEN,
+               NULL, HFILL }
+        },
+        { &hf_openflow_stp_learn,
+            { "Learning but not relaying frames", "openflow.stp_learn",
+               FT_BOOLEAN, 32, NULL, OFPPS_STP_LEARN,
+               NULL, HFILL }
+        },
+        { &hf_openflow_stp_forward,
+            { "Learning and relaying frames", "openflow.stp_forward",
+               FT_BOOLEAN, 32, NULL, OFPPS_STP_FORWARD,
+               NULL, HFILL }
+        },
+        { &hf_openflow_stp_block,
+            { "Not part of spanning tree", "openflow.stp_block",
+               FT_BOOLEAN, 32, NULL, OFPPS_STP_BLOCK,
+               NULL, HFILL }
+        },
+        { &hf_openflow_stp_mask,
+            { "Bit mask for OFPPS_STP", "openflow.stp_mask",
+               FT_BOOLEAN, 32, NULL, OFPPS_STP_MASK,
+               NULL, HFILL }
+        },
+        { &hf_openflow_10mb_hd,
+            { "10 Mb half-duplex rate support", "openflow.10mb_hd",
+               FT_BOOLEAN, 32, NULL, OFPPF_10MB_HD,
+               NULL, HFILL }
+        },
+        { &hf_openflow_10mb_fd,
+            { "10 Mb full-duplex rate support", "openflow.10mb_fd",
+               FT_BOOLEAN, 32, NULL, OFPPF_10MB_FD,
+               NULL, HFILL }
+        },
+        { &hf_openflow_100mb_hd,
+            { "100 Mb half-duplex rate support", "openflow.100mb_hd",
+               FT_BOOLEAN, 32, NULL, OFPPF_100MB_HD,
+               NULL, HFILL }
+        },
+        { &hf_openflow_100mb_fd,
+            { "100 Mb full-duplex rate support", "openflow.100mb_0fd",
+               FT_BOOLEAN, 32, NULL, OFPPF_100MB_FD,
+               NULL, HFILL }
+        },
+        { &hf_openflow_1gb_hd,
+            { "1 Gb half-duplex rate support", "openflow.1gb_hd",
+               FT_BOOLEAN, 32, NULL, OFPPF_1GB_HD,
+               NULL, HFILL }
+        },
+        { &hf_openflow_1gb_fd,
+            { "1 Gb full-duplex rate support", "openflow.1gb_fd",
+               FT_BOOLEAN, 32, NULL, OFPPF_1GB_FD,
+               NULL, HFILL }
+        },
+        { &hf_openflow_10gb_fd,
+            { "10 Gb full-duplex rate support", "openflow.10gb_fd",
+               FT_BOOLEAN, 32, NULL, OFPPF_10GB_FD,
+               NULL, HFILL }
+        },
+        { &hf_openflow_copper,
+            { "Copper medium", "openflow.copper",
+               FT_BOOLEAN, 32, NULL, OFPPF_COPPER,
+               NULL, HFILL }
+        },
+        { &hf_openflow_fiber,
+            { "Fiber medium", "openflow.fiber",
+               FT_BOOLEAN, 32, NULL, OFPPF_FIBER,
+               NULL, HFILL }
+        },
+        { &hf_openflow_autoneg,
+            { "Auto-negotiation", "openflow.autoneg",
+               FT_BOOLEAN, 32, NULL, OFPPF_AUTONEG,
+               NULL, HFILL }
+        },
+        { &hf_openflow_pause,
+            { "Pause", "openflow.pause",
+               FT_BOOLEAN, 32, NULL, OFPPF_PAUSE,
+               NULL, HFILL }
+        },
+        { &hf_openflow_pause_asym,
+            { "Asymmetric pause", "openflow.pause_asym",
+               FT_BOOLEAN, 32, NULL, OFPPF_PAUSE_ASYM,
+               NULL, HFILL }
+        },
+    };
+
+    static gint *ett[] = {
+        &ett_openflow,
+        &ett_openflow_path_id,
+        &ett_openflow_cap,
+        &ett_openflow_act,
+        &ett_openflow_port,
+        &ett_openflow_port_cnf,
+        &ett_openflow_port_state,
+		&ett_port_cf
+    };
+
+    /* Register the protocol name and description */
+    proto_openflow = proto_register_protocol("OpenFlow",
+            "openflow", "openflow");
+
+    /* Required function calls to register the header fields and subtrees */
+    proto_register_field_array(proto_openflow, hf, array_length(hf));
+    proto_register_subtree_array(ett, array_length(ett));
+
+    openflow_module = prefs_register_protocol(proto_openflow, proto_reg_handoff_openflow);
+
+    /* Register port preference */
+    prefs_register_uint_preference(openflow_module, "tcp.port", "openflow TCP Port",
+            " openflow TCP port if other than the default",
+            10, &g_openflow_port);
+}
+
+void
+proto_reg_handoff_openflow(void)
+{
+    static gboolean initialized = FALSE;
+    static dissector_handle_t openflow_handle;
+    static int currentPort;
+
+    if (!initialized) {
+        openflow_handle = new_create_dissector_handle(dissect_openflow, proto_openflow);
+        initialized = TRUE;
+
+    } else {
+        dissector_delete_uint("tcp.port", currentPort, openflow_handle);
+    }
+
+    currentPort = g_openflow_port;
+
+    dissector_add_uint("tcp.port", currentPort, openflow_handle);
+}
+
+
+/*
+ * Editor modelines  -  http://www.wireshark.org/tools/modelines.html
+ *
+ * Local variables:
+ * c-basic-offset: 4
+ * tab-width: 8
+ * indent-tabs-mode: nil
+ * End:
+ *
+ * vi: set shiftwidth=4 tabstop=8 expandtab:
+ * :indentSize=4:tabSize=8:noTabs=true:
+ */