From Michal Labedzki:

Bluetooth: Improve internal Decode By Channel for RFCOMM

Use UAT to allow user to force set top dissector per channel.
Only first found dissection for specified channel is used,
the rest can be used as well-known protocol on channel, but not for
current logs.  Also user can turn on/off this dissection by one-click
preference.

https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=7639

svn path=/trunk/; revision=45037

1 files changed, 60 insertions, 11 deletions

diff --git a/epan/dissectors/packet-btrfcomm.c b/epan/dissectors/packet-btrfcomm.c
index b4a7abcdac..2b9d555479 100644
--- a/epan/dissectors/packet-btrfcomm.c
+++ b/epan/dissectors/packet-btrfcomm.c
@@ -40,6 +40,7 @@
 #include <epan/emem.h>
 #include <epan/expert.h>
 #include <epan/tap.h>
+#include <epan/uat.h>
 #include "packet-btsdp.h"
 #include "packet-btl2cap.h"
 #include "packet-btrfcomm.h"
@@ -117,12 +118,31 @@ typedef struct _dlci_state_t {
     char    do_credit_fc;
 } dlci_state_t;
 
+typedef struct {
+    guint               channel;
+    gchar*              payload_proto_name;
+    dissector_handle_t  payload_proto;
+} uat_rfcomm_channels_t;
+
+static gboolean               rfcomm_channels_enabled   = FALSE;
+static uat_t                  *uat_rfcomm_channels      = NULL;
+static uat_rfcomm_channels_t  *rfcomm_channels          = NULL;
+static guint                  num_rfcomm_channels       = 0;
+
+UAT_DEC_CB_DEF(rfcomm_channels, channel, uat_rfcomm_channels_t)
+UAT_PROTO_DEF(rfcomm_channels, payload_proto, payload_proto, payload_proto_name, uat_rfcomm_channels_t)
+
+static uat_field_t uat_rfcomm_channels_fields[] = {
+    UAT_FLD_DEC(rfcomm_channels, channel, "RFCOMM Channel",
+            "Range: 0-32"),
+    UAT_FLD_PROTO(rfcomm_channels, payload_proto, "Payload protocol",
+            "Dissector name used to decode RFCOMM channel"),
+    UAT_END_FIELDS
+};
+
 static dissector_handle_t data_handle;
 static dissector_handle_t ppp_handle;
 
-static const char *decode_by_dissector_name = "";
-static guint       decode_by_channel = 0;
-
 static const value_string vs_ctl_pn_i[] = {
     {0x0, "use UIH Frames"},
 #if 0    /* specified by 07.10, but not used by RFCOMM */
@@ -218,6 +238,17 @@ static const value_string vs_cr[] = {
     {0, NULL}
 };
 
+static dissector_handle_t
+find_proto_by_channel(guint channel) {
+    guint i_channel;
+
+    for (i_channel = 0; i_channel < num_rfcomm_channels; ++i_channel) {
+        if (rfcomm_channels[i_channel].channel == channel) {
+            return rfcomm_channels[i_channel].payload_proto;
+        }
+    }
+    return NULL;
+}
 
 static int
 get_le_multi_byte_value(tvbuff_t *tvb, int offset, proto_tree *tree, guint32 *val_ptr, int hf_index)
@@ -691,8 +722,8 @@ dissect_btrfcomm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
         rfcomm_data.cid = l2cap_data->cid;
         rfcomm_data.dlci = dlci;
 
-        decode_by_dissector = find_dissector(decode_by_dissector_name);
-        if (decode_by_dissector && decode_by_channel && decode_by_channel == (dlci >> 1)) {
+        decode_by_dissector = find_proto_by_channel(dlci >> 1);
+        if (rfcomm_channels_enabled && decode_by_dissector) {
             call_dissector(decode_by_dissector, next_tvb, pinfo, tree);
         } else if (!dissector_try_uint(rfcomm_channel_dissector_table, (guint32) dlci >> 1,
                 next_tvb, pinfo, tree)) {
@@ -707,11 +738,11 @@ dissect_btrfcomm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
     proto_tree_add_item(rfcomm_tree, hf_fcs, tvb, fcs_offset, 1, ENC_LITTLE_ENDIAN);
 }
 
-
 void
 proto_register_btrfcomm(void)
 {
     module_t *module;
+
     static hf_register_info hf[] = {
         { &hf_dlci,
           { "DLCI", "btrfcomm.dlci",
@@ -918,11 +949,29 @@ proto_register_btrfcomm(void)
     prefs_register_static_text_preference(module, "rfcomm.version",
             "Bluetooth Protocol RFCOMM version: 1.1", "Version of protocol supported by this dissector.");
 
-    prefs_register_uint_preference(module, "rfcomm.decode_by.channel",
-            "Decoby by: channel", "Channel - used to decode by RFCOMM channel", 10, &decode_by_channel);
-
-    prefs_register_string_preference(module, "rfcomm.decode_by.name",
-            "Decoby by: dissector name", "Dissector name - used to decode by RFCOMM channel", &decode_by_dissector_name);
+    prefs_register_bool_preference(module, "rfcomm.decode_by.enabled",
+            "Enable Force Decode by Channel",
+            "Turn on/off decode by next rules",
+            &rfcomm_channels_enabled);
+
+    uat_rfcomm_channels = uat_new("Force Decode by Channel",
+            sizeof(uat_rfcomm_channels_t),
+            "rfcomm_channels",
+            TRUE,
+            (void*) &rfcomm_channels,
+            &num_rfcomm_channels,
+            UAT_AFFECTS_DISSECTION,
+            NULL,
+            NULL,
+            NULL,
+            NULL,
+            NULL,
+            uat_rfcomm_channels_fields);
+
+    prefs_register_uat_preference(module, "rfcomm.channels",
+            "Force Decode by channel",
+            "Decode by channel",
+            uat_rfcomm_channels);
 }
 
 static int