USB CCID: use Decode As to select the payload protocol

Remove the special case for vid 0x072F, pid 0x2200. We should be able to
set Decode As for this (vid, pid) to USB CCID and then use the new
Decode As mechanism to select the next protocol.

Register GSM SIM, ISO7816, PN532 and ACR122 as possible payloads
for USB CCID.

Change-Id: I8237cc9123655d3b289b0564ffb83a32434bebfc
Reviewed-on: https://code.wireshark.org/review/22290
Petri-Dish: Anders Broman <a.broman58@gmail.com>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Anders Broman <a.broman58@gmail.com>

1 files changed, 23 insertions, 52 deletions

diff --git a/epan/dissectors/packet-usb-ccid.c b/epan/dissectors/packet-usb-ccid.c
index 7709c7560f..91ed844705 100644
--- a/epan/dissectors/packet-usb-ccid.c
+++ b/epan/dissectors/packet-usb-ccid.c
@@ -27,12 +27,15 @@
  */
 #include "config.h"
 
+#include <epan/decode_as.h>
 #include <epan/packet.h>
 #include <epan/prefs.h>
 #include "packet-usb.h"
 
 static int proto_ccid = -1;
 
+static dissector_table_t subdissector_table;
+
 static int hf_ccid_bMessageType = -1;
 static int hf_ccid_dwLength = -1;
 static int hf_ccid_bSlot = -1;
@@ -336,22 +339,16 @@ static gint ett_ccid_pin_support = -1;
 static gint ett_ccid_slot_change = -1;
 static gint ett_ccid_status = -1;
 
-/* Table of payload types - adapted from the I2C dissector */
-enum {
-    SUB_DATA = 0,
-    SUB_ISO7816,
-    SUB_GSM_SIM,
-    SUB_PN532,
-    SUB_ACR122_PN532,
-
-    SUB_MAX
-};
-
-typedef gboolean (*sub_checkfunc_t)(packet_info *);
+static void usb_ccid_prompt(packet_info *pinfo _U_, gchar* result)
+{
+    g_snprintf(result, MAX_DECODE_AS_PROMPT_LEN, "Next level protocol as");
+}
 
-static dissector_handle_t sub_handles[SUB_MAX];
-static gint sub_selected = SUB_DATA;
 
+static gpointer usb_ccid_value(packet_info *pinfo _U_)
+{
+    return 0;
+}
 
 static gint
 dissect_usb_ccid_descriptor(tvbuff_t *tvb, packet_info *pinfo _U_,
@@ -571,12 +568,7 @@ dissect_ccid(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
         /* sent/received is from the perspective of the card reader */
         pinfo->p2p_dir = P2P_DIR_SENT;
 
-        /* See if the dissector isn't Data */
-        if (sub_selected != SUB_DATA) {
-            call_dissector_with_data(sub_handles[sub_selected], next_tvb, pinfo, tree, usb_conv_info);
-        } else if (usb_conv_info->deviceVendor == 0x072F && usb_conv_info->deviceProduct == 0x2200) {
-            call_dissector_with_data(sub_handles[SUB_ACR122_PN532], next_tvb, pinfo, tree, usb_conv_info);
-        } else { /* The user only wants plain data */
+        if (!dissector_try_uint_new(subdissector_table, 0, next_tvb, pinfo, tree, TRUE, usb_conv_info)) {
             call_data_dissector(next_tvb, pinfo, tree);
         }
         break;
@@ -600,17 +592,7 @@ dissect_ccid(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
         next_tvb = tvb_new_subset_length(tvb, 10, payload_len);
         pinfo->p2p_dir = P2P_DIR_RECV;
 
-        if (sub_selected == SUB_PN532) {
-            call_dissector_with_data(sub_handles[SUB_PN532], next_tvb, pinfo, tree, usb_conv_info);
-        } else if (sub_selected == SUB_GSM_SIM) {  /* Try to dissect responses to GSM SIM packets */
-            call_dissector(sub_handles[SUB_GSM_SIM], next_tvb, pinfo, tree);
-        } else if (sub_selected == SUB_ACR122_PN532) {
-            call_dissector_with_data(sub_handles[SUB_ACR122_PN532], next_tvb, pinfo, tree, usb_conv_info);
-        } else if (sub_selected == SUB_ISO7816) {
-            call_dissector(sub_handles[SUB_ISO7816], next_tvb, pinfo, tree);
-        } else if (usb_conv_info->deviceVendor == 0x072F && usb_conv_info->deviceProduct == 0x2200) {
-            call_dissector_with_data(sub_handles[SUB_ACR122_PN532], next_tvb, pinfo, tree, usb_conv_info);
-        } else {
+        if (!dissector_try_uint_new(subdissector_table, 0, next_tvb, pinfo, tree, TRUE, usb_conv_info)) {
             call_data_dissector(next_tvb, pinfo, tree);
         }
         break;
@@ -657,6 +639,12 @@ dissect_ccid(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
 void
 proto_register_ccid(void)
 {
+    static build_valid_func usb_ccid_build_value[1] = { usb_ccid_value };
+    static decode_as_value_t usb_ccid_da_values = { usb_ccid_prompt, 1, usb_ccid_build_value };
+    static decode_as_t usb_ccid_da = {"USB CCID", "Transport",
+        "usbccid.subdissector", 1, 0, &usb_ccid_da_values, NULL, NULL,
+        decode_as_default_populate_list, decode_as_default_reset, decode_as_default_change, NULL};
+
     static hf_register_info hf[] = {
 
         {&hf_ccid_bMessageType,
@@ -897,26 +885,15 @@ proto_register_ccid(void)
         &ett_ccid_status
     };
 
-    static const enum_val_t sub_enum_vals[] = {
-        { "data", "Data", SUB_DATA },
-        { "iso7816", "Generic ISO 7816", SUB_ISO7816 },
-        { "gsm_sim", "GSM SIM", SUB_GSM_SIM },
-        { "pn532", "NXP PN532", SUB_PN532},
-        { "acr122", "ACR122 PN532", SUB_ACR122_PN532},
-        { NULL, NULL, 0 }
-    };
-
-    module_t *pref_mod;
-
     proto_ccid = proto_register_protocol("USB CCID", "USBCCID", "usbccid");
     proto_register_field_array(proto_ccid, hf, array_length(hf));
     proto_register_subtree_array(ett, array_length(ett));
 
-    pref_mod = prefs_register_protocol(proto_ccid, NULL);
-    prefs_register_enum_preference(pref_mod, "prtype", "PC -> Reader Payload Type", "How commands from the PC to the reader are interpreted",
-        &sub_selected, sub_enum_vals, FALSE);
-
     usb_ccid_handle = register_dissector("usbccid", dissect_ccid, proto_ccid);
+
+    subdissector_table = register_dissector_table(
+            "usbccid.subdissector", "USB CCID payload", proto_ccid, FT_UINT32, BASE_HEX);
+    register_decode_as(&usb_ccid_da);
 }
 
 /* Handler registration */
@@ -934,12 +911,6 @@ proto_reg_handoff_ccid(void)
     dissector_add_for_decode_as("usb.device", usb_ccid_handle);
     dissector_add_for_decode_as("usb.product", usb_ccid_handle);
     dissector_add_for_decode_as("usb.protocol", usb_ccid_handle);
-
-    sub_handles[SUB_DATA] = find_dissector("data");
-    sub_handles[SUB_ISO7816] = find_dissector_add_dependency("iso7816", proto_ccid);
-    sub_handles[SUB_GSM_SIM] = find_dissector_add_dependency("gsm_sim.part", proto_ccid);
-    sub_handles[SUB_PN532] = find_dissector_add_dependency("pn532", proto_ccid);
-    sub_handles[SUB_ACR122_PN532] = find_dissector_add_dependency("acr122", proto_ccid);
 }
 
 /*