From Andrew Feren:

Add preference to allow user to configure the port(s) to use when identifying
sFlow.

git-svn-id: http://anonsvn.wireshark.org/wireshark/trunk@23153 f5534014-38df-0310-8fa8-9805f1628bb7

diff --git a/epan/dissectors/packet-sflow.c b/epan/dissectors/packet-sflow.c
index 605b271e370dcbac5117d8778abd6cb540fbf3a0..cb3d89a92ff855256f5334cf090f8df24c9273b1 100644 (file)
--- a/epan/dissectors/packet-sflow.c
+++ b/epan/dissectors/packet-sflow.c
@@ -55,9 +55,24 @@
 #include <glib.h>
 
 #include <epan/packet.h>
+#include <epan/prefs.h>
+
 /*#include "packet-sflow.h"*/
 
-#define UDP_PORT_SFLOW 6343
+#define SFLOW_UDP_PORTS "6343"
+
+static dissector_handle_t sflow_handle;
+
+/*
+ *     global_sflow_ports : holds the configured range of ports for sflow
+ */
+static range_t *global_sflow_ports = NULL;
+
+/*
+ *     sflow_ports : holds the currently used range of ports for sflow
+ */
+static range_t *sflow_ports = NULL;
+
 
 #define ADDRESS_IPV4 1
 #define ADDRESS_IPV6 2
@@ -324,10 +339,12 @@ static dissector_handle_t ipv4_handle;
 static dissector_handle_t ipv6_handle;
 static dissector_handle_t mpls_handle;
 
+void proto_reg_handoff_sflow(void);
+
 /* dissect a sampled header - layer 2 protocols */
 static gint
 dissect_sflow_sampled_header(tvbuff_t *tvb, packet_info *pinfo,
-                                                        proto_tree *tree, volatile gint offset)
+                            proto_tree *tree, volatile gint offset)
 {
        guint32         header_proto, frame_length;
        volatile        guint32         header_length;
@@ -754,7 +771,7 @@ dissect_sflow_samples(tvbuff_t *tvb, packet_info *pinfo,
 }
 
 /* Code to actually dissect the packets */
-static void
+static int
 dissect_sflow(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 {
 
@@ -813,6 +830,7 @@ dissect_sflow(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
                offset += 16;
                break;
        default:
+               return 0;
                /* unknown address.  this will cause a malformed packet.  */
                break;
        };
@@ -857,6 +875,38 @@ dissect_sflow(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
                            offset);
                }
        }
+
+       return tvb_length(tvb);
+}
+
+
+static void
+sflow_delete_callback(guint32 port)
+{
+    if ( port ) {
+       dissector_delete("udp.port", port, sflow_handle);
+    }
+}
+static void
+sflow_add_callback(guint32 port)
+{
+    if ( port ) {
+       dissector_add("udp.port", port, sflow_handle);
+    }
+}
+
+
+static void
+sflow_reinit(void)
+{
+       if (sflow_ports) {
+         range_foreach(sflow_ports, sflow_delete_callback);
+         g_free(sflow_ports);
+       }
+
+       sflow_ports = range_copy(global_sflow_ports);
+
+       range_foreach(sflow_ports, sflow_add_callback);
 }
 
 
@@ -868,7 +918,8 @@ dissect_sflow(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 
 void
 proto_register_sflow(void)
-{                 
+{
+       module_t *sflow_module;
 
 /* Setup list of header fields  See Section 1.6.1 for details*/
        static hf_register_info hf[] = {
@@ -1084,17 +1135,47 @@ proto_register_sflow(void)
 /* Required function calls to register the header fields and subtrees used */
        proto_register_field_array(proto_sflow, hf, array_length(hf));
        proto_register_subtree_array(ett, array_length(ett));
+
+/* Register our configuration options for sFlow */
+       sflow_module = prefs_register_protocol(proto_sflow,
+                                              proto_reg_handoff_sflow);
+
+/* Set default Neflow port(s) */
+       range_convert_str(&global_sflow_ports, SFLOW_UDP_PORTS,
+                         MAX_UDP_PORT);
+
+       prefs_register_obsolete_preference(sflow_module, "udp.port");
+
+       prefs_register_range_preference(sflow_module, "ports",
+                                       "SFlow UDP Port(s)",
+                                       "Set the port(s) for sFlow messages"
+                                       " (default: " SFLOW_UDP_PORTS ")",
+                                       &global_sflow_ports, MAX_UDP_PORT);
+
+       register_init_routine(&sflow_reinit);
 }
 
 
-/* If this dissector uses sub-dissector registration add a registration routine.
-   This format is required because a script is used to find these routines and
-   create the code that calls these routines.
+/* If this dissector uses sub-dissector registration add a
+   registration routine.  This format is required because a script is
+   used to find these routines and create the code that calls these
+   routines.
 */
 void
 proto_reg_handoff_sflow(void)
 {
-       dissector_handle_t sflow_handle;
+       static int sflow_prefs_initialized = FALSE;
+       if (!sflow_prefs_initialized) {
+               sflow_handle = new_create_dissector_handle(dissect_sflow,
+                                                          proto_sflow);
+
+               sflow_prefs_initialized = TRUE;
+       }
+
+
+       sflow_reinit();
+
+       /*dissector_handle_t sflow_handle;*/
 
        /*
         * XXX - should this be done with a dissector table?
@@ -1120,8 +1201,4 @@ proto_reg_handoff_sflow(void)
        ipv4_handle = find_dissector("ip");
        ipv6_handle = find_dissector("ipv6");
        mpls_handle = find_dissector("mpls");
-
-       sflow_handle = create_dissector_handle(dissect_sflow,
-           proto_sflow);
-       dissector_add("udp.port", UDP_PORT_SFLOW, sflow_handle);
 }