Pass the 802.11 pseudo-header as an argument.

Rather than accessing it through pinfo->pseudo_header, have it passed as
an argument.

This means we no longer tweak the pseudo-header filled in by libwiretap,
but instead construct our own pseudo-header, which is a bit cleaner.

It also opens up the possibility of other dissectors passing radio
information down to the 802.11 dissector, so it can display it in a
better-organized format than the raw metadata headers for
radiotap/PPI/Prism/AVS/etc., and having some of the options for 802.11
dissection (Atheros padding, Centrino stuff, etc.) also passed in
through that pseudo-header so we have fewer arguments to
dissect_ieee80211_common().

Change-Id: I470300a0407ebf029c542f7ca5878593563a70a9
Reviewed-on: https://code.wireshark.org/review/8980
Reviewed-by: Guy Harris <guy@alum.mit.edu>

4 files changed, 106 insertions, 59 deletions

diff --git a/epan/dissectors/packet-ieee80211-radio.c b/epan/dissectors/packet-ieee80211-radio.c
index da32cfd376..f965396e14 100644
--- a/epan/dissectors/packet-ieee80211-radio.c
+++ b/epan/dissectors/packet-ieee80211-radio.c
@@ -464,8 +464,8 @@ static gint ett_radio = -1;
  * Dissect 802.11 with a variable-length link-layer header and a pseudo-
  * header containing radio information.
  */
-static void
-dissect_radio (tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
+static int
+dissect_radio (tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree, void *data)
 {
   proto_item *ti = NULL;
   proto_tree *radio_tree = NULL;
@@ -590,7 +590,7 @@ dissect_radio (tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
 
   /* dissect the 802.11 header next */
   pinfo->current_proto = "IEEE 802.11";
-  call_dissector(ieee80211_handle, tvb, pinfo, tree);
+  return call_dissector_with_data(ieee80211_handle, tvb, pinfo, tree, data);
 }
 
 static hf_register_info hf_radio[] = {
@@ -652,7 +652,7 @@ void proto_reg_handoff_ieee80211_radio(void)
   dissector_handle_t radio_handle;
 
   /* Register handoff to radio-header dissectors */
-  radio_handle = create_dissector_handle(dissect_radio, proto_radio);
+  radio_handle = new_create_dissector_handle(dissect_radio, proto_radio);
   dissector_add_uint("wtap_encap", WTAP_ENCAP_IEEE_802_11_WITH_RADIO,
                      radio_handle);
   ieee80211_handle = find_dissector("wlan");
diff --git a/epan/dissectors/packet-ieee80211-radiotap.c b/epan/dissectors/packet-ieee80211-radiotap.c
index 179c650956..44d7c2e0fb 100644
--- a/epan/dissectors/packet-ieee80211-radiotap.c
+++ b/epan/dissectors/packet-ieee80211-radiotap.c
@@ -586,6 +586,7 @@ dissect_radiotap(tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
 	struct _radiotap_info              *radiotap_info;
 	static struct _radiotap_info        rtp_info_arr;
 	struct ieee80211_radiotap_iterator  iter;
+	struct ieee_802_11_phdr phdr;
 
 	/* our non-standard overrides */
 	static struct radiotap_override overrides[] = {
@@ -601,6 +602,11 @@ dissect_radiotap(tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
 
 	radiotap_info = &rtp_info_arr;
 
+	/* We don't have any 802.11 metadata yet. */
+	phdr.fcs_len = -1;
+	phdr.decrypted = FALSE;
+	phdr.presence_flags = 0;
+
 	col_set_str(pinfo->cinfo, COL_PROTOCOL, "WLAN");
 	col_clear(pinfo->cinfo, COL_INFO);
 
@@ -827,6 +833,11 @@ dissect_radiotap(tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
 
 		case IEEE80211_RADIOTAP_FLAGS: {
 			rflags = tvb_get_guint8(tvb, offset);
+			if (rflags & IEEE80211_RADIOTAP_F_FCS)
+				phdr.fcs_len = 4;
+			else
+				phdr.fcs_len = 0;
+
 			if (tree) {
 				proto_tree *flags_tree;
 
@@ -1438,12 +1449,6 @@ dissect_radiotap(tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
 		proto_item_append_text(ti, " (malformed)");
 	}
 
-	/* This handles the case of an FCS exiting at the end of the frame. */
-	if (rflags & IEEE80211_RADIOTAP_F_FCS)
-		pinfo->pseudo_header->ieee_802_11.fcs_len = 4;
-	else
-		pinfo->pseudo_header->ieee_802_11.fcs_len = 0;
-
  hand_off_to_80211:
 	/* Grab the rest of the frame. */
 	next_tvb = tvb_new_subset_remaining(tvb, length);
@@ -1452,17 +1457,19 @@ dissect_radiotap(tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
 	 * This can only happen if the backward-compat configuration option
 	 * is chosen by the user. */
 	if (hdr_fcs_ti) {
+		guint captured_length = tvb_captured_length(next_tvb);
+		guint reported_length = tvb_reported_length(next_tvb);
+		guint fcs_len = (phdr.fcs_len > 0) ? phdr.fcs_len : 0;
+
 		/* It would be very strange for the header to have an FCS for the
 		 * frame *and* the frame to have the FCS at the end, but it's possible, so
 		 * take that into account by using the FCS length recorded in pinfo. */
 
 		/* Watch out for [erroneously] short frames */
-		if (tvb_length(next_tvb) >
-		    (unsigned int)pinfo->pseudo_header->ieee_802_11.fcs_len) {
+		if (captured_length >= reported_length &&
+		    captured_length > fcs_len) {
 			calc_fcs =
-			    crc32_802_tvb(next_tvb,
-			    	tvb_length(next_tvb) -
-			    	pinfo->pseudo_header->ieee_802_11.fcs_len);
+			    crc32_802_tvb(next_tvb, tvb_length(next_tvb) - fcs_len);
 
 			/* By virtue of hdr_fcs_ti being set, we know that 'tree' is set,
 			 * so there's no need to check it here. */
@@ -1486,10 +1493,10 @@ dissect_radiotap(tvbuff_t * tvb, packet_info * pinfo, proto_tree * tree)
 		}
 	}
 
-	/* dissect the 802.11 header next */
-	call_dissector((rflags & IEEE80211_RADIOTAP_F_DATAPAD) ?
-		       ieee80211_datapad_handle : ieee80211_handle,
-		       next_tvb, pinfo, tree);
+	/* dissect the 802.11 packet next */
+	call_dissector_with_data((rflags & IEEE80211_RADIOTAP_F_DATAPAD) ?
+	    ieee80211_datapad_handle : ieee80211_handle, next_tvb, pinfo,
+	    tree, &phdr);
 
 	tap_queue_packet(radiotap_tap, pinfo, radiotap_info);
 }
diff --git a/epan/dissectors/packet-ieee80211.c b/epan/dissectors/packet-ieee80211.c
index 339dcf5c75..a09caaca2c 100644
--- a/epan/dissectors/packet-ieee80211.c
+++ b/epan/dissectors/packet-ieee80211.c
@@ -16561,11 +16561,12 @@ typedef enum {
  * have to go digging for bits in various locations instead.
  */
 
-static void
+static int
 dissect_ieee80211_common (tvbuff_t *tvb, packet_info *pinfo,
                           proto_tree *tree, gboolean fixed_length_header, gint fcs_len,
                           gboolean wlan_broken_fc, gboolean datapad,
-                          gboolean is_ht, gboolean is_centrino)
+                          gboolean is_ht, gboolean is_centrino,
+                          struct ieee_802_11_phdr *phdr)
 {
   guint16          fcf, flags, frame_type_subtype, ctrl_fcf, ctrl_type_subtype;
   guint16          seq_control;
@@ -17701,7 +17702,7 @@ dissect_ieee80211_common (tvbuff_t *tvb, packet_info *pinfo,
        * No-data frames don't have a body.
        */
       if (DATA_FRAME_IS_NULL(frame_type_subtype))
-        return;
+        return tvb_captured_length(tvb);
 
       if (!wlan_subdissector) {
         guint fnum = 0;
@@ -17759,15 +17760,17 @@ dissect_ieee80211_common (tvbuff_t *tvb, packet_info *pinfo,
       break;
 
     case CONTROL_FRAME:
-      return;
-        case EXTENSION_FRAME:
+      return tvb_captured_length(tvb);
+
+    case EXTENSION_FRAME:
       break;
+
     default:
-      return;
+      return tvb_captured_length(tvb);
     }
 
   if (IS_PROTECTED(FCF_FLAGS(fcf))
-      && !pinfo->pseudo_header->ieee_802_11.decrypted
+      && (phdr == NULL || !phdr->decrypted)
       && (wlan_ignore_wep != WLAN_IGNORE_WEP_WO_IV)) {
     /*
      * It's a WEP or WPA encrypted frame, and it hasn't already been
@@ -18263,17 +18266,21 @@ dissect_ieee80211_common (tvbuff_t *tvb, packet_info *pinfo,
   whdr->stats = wlan_stats;
   tap_queue_packet(wlan_tap, pinfo, whdr);
   memset (&wlan_stats, 0, sizeof wlan_stats);
+
+  return tvb_captured_length(tvb);
 }
 
 /*
  * Dissect 802.11 with a variable-length link-layer header and with the FCS
  * presence or absence indicated by the pseudo-header.
  */
-static void
-dissect_ieee80211 (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+static int
+dissect_ieee80211 (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
 {
-  dissect_ieee80211_common (tvb, pinfo, tree, FALSE,
-                            pinfo->pseudo_header->ieee_802_11.fcs_len, FALSE, FALSE, FALSE, FALSE);
+  struct ieee_802_11_phdr *phdr = (struct ieee_802_11_phdr *)data;
+
+  return dissect_ieee80211_common (tvb, pinfo, tree, FALSE,
+                                   (phdr == NULL) ? -1 : phdr->fcs_len, FALSE, FALSE, FALSE, FALSE, phdr);
 }
 
 /*
@@ -18283,7 +18290,7 @@ dissect_ieee80211 (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 static void
 dissect_ieee80211_withfcs (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 {
-  dissect_ieee80211_common (tvb, pinfo, tree, FALSE, 4, FALSE, FALSE, FALSE, FALSE);
+  dissect_ieee80211_common (tvb, pinfo, tree, FALSE, 4, FALSE, FALSE, FALSE, FALSE, NULL);
 }
 
 /*
@@ -18293,28 +18300,32 @@ dissect_ieee80211_withfcs (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 static void
 dissect_ieee80211_withoutfcs (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 {
-  dissect_ieee80211_common (tvb, pinfo, tree, FALSE, 0, FALSE, FALSE, FALSE, FALSE);
+  dissect_ieee80211_common (tvb, pinfo, tree, FALSE, 0, FALSE, FALSE, FALSE, FALSE, NULL);
 }
 
 /*
  * Dissect 802.11 with a variable-length link-layer header.
  */
-static void
-dissect_ieee80211_centrino(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+static int
+dissect_ieee80211_centrino(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
 {
-  dissect_ieee80211_common (tvb, pinfo, tree, FALSE,
-                            pinfo->pseudo_header->ieee_802_11.fcs_len, FALSE, FALSE, FALSE, TRUE);
+  struct ieee_802_11_phdr *phdr = (struct ieee_802_11_phdr *)data;
+
+  return dissect_ieee80211_common (tvb, pinfo, tree, FALSE,
+                                   (phdr == NULL) ? -1 : phdr->fcs_len, FALSE, FALSE, FALSE, TRUE, phdr);
 }
 
 /*
  * Dissect 802.11 with a variable-length link-layer header and data padding
  * and with the FCS presence or absence indicated by the pseudo-header.
  */
-static void
-dissect_ieee80211_datapad (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+static int
+dissect_ieee80211_datapad (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
 {
-  dissect_ieee80211_common (tvb, pinfo, tree, FALSE,
-                            pinfo->pseudo_header->ieee_802_11.fcs_len, FALSE, TRUE, FALSE, FALSE);
+  struct ieee_802_11_phdr *phdr = (struct ieee_802_11_phdr *)data;
+
+  return dissect_ieee80211_common (tvb, pinfo, tree, FALSE,
+                                   (phdr == NULL) ? -1 : phdr->fcs_len, FALSE, TRUE, FALSE, FALSE, phdr);
 }
 
 /*
@@ -18324,7 +18335,7 @@ dissect_ieee80211_datapad (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 static void
 dissect_ieee80211_datapad_withfcs (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 {
-  dissect_ieee80211_common (tvb, pinfo, tree, FALSE, 4, FALSE, TRUE, FALSE, FALSE);
+  dissect_ieee80211_common (tvb, pinfo, tree, FALSE, 4, FALSE, TRUE, FALSE, FALSE, NULL);
 }
 
 /*
@@ -18334,7 +18345,7 @@ dissect_ieee80211_datapad_withfcs (tvbuff_t *tvb, packet_info *pinfo, proto_tree
 static void
 dissect_ieee80211_datapad_withoutfcs (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 {
-  dissect_ieee80211_common (tvb, pinfo, tree, FALSE, 0, FALSE, TRUE, FALSE, FALSE);
+  dissect_ieee80211_common (tvb, pinfo, tree, FALSE, 0, FALSE, TRUE, FALSE, FALSE, NULL);
 }
 
 /*
@@ -18345,7 +18356,7 @@ dissect_ieee80211_datapad_withoutfcs (tvbuff_t *tvb, packet_info *pinfo, proto_t
 static void
 dissect_ieee80211_bsfc (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 {
-  dissect_ieee80211_common (tvb, pinfo, tree, FALSE, 0, TRUE, FALSE, FALSE, FALSE);
+  dissect_ieee80211_common (tvb, pinfo, tree, FALSE, 0, TRUE, FALSE, FALSE, FALSE, NULL);
 }
 
 /*
@@ -18355,7 +18366,7 @@ dissect_ieee80211_bsfc (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 static void
 dissect_ieee80211_fixed (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 {
-  dissect_ieee80211_common (tvb, pinfo, tree, TRUE, 0, FALSE, FALSE, FALSE, FALSE);
+  dissect_ieee80211_common (tvb, pinfo, tree, TRUE, 0, FALSE, FALSE, FALSE, FALSE, NULL);
 }
 
 /*
@@ -18363,11 +18374,13 @@ dissect_ieee80211_fixed (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  * XXX - Can we tell if a frame is +HTC just by looking at the MAC header?
  * If so, we can dispense with this.
  */
-static void
-dissect_ieee80211_ht (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+static int
+dissect_ieee80211_ht (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
 {
-  dissect_ieee80211_common (tvb, pinfo, tree, FALSE,
-                            pinfo->pseudo_header->ieee_802_11.fcs_len, FALSE, FALSE, TRUE, FALSE);
+  struct ieee_802_11_phdr *phdr = (struct ieee_802_11_phdr *)data;
+
+  return dissect_ieee80211_common (tvb, pinfo, tree, FALSE,
+                                   (phdr == NULL) ? -1 : phdr->fcs_len, FALSE, FALSE, TRUE, FALSE, phdr);
 }
 
 static void
@@ -26914,15 +26927,15 @@ proto_register_ieee80211 (void)
   expert_ieee80211 = expert_register_protocol(proto_wlan);
   expert_register_field_array(expert_ieee80211, ei, array_length(ei));
 
-  register_dissector("wlan",                    dissect_ieee80211,                    proto_wlan);
+  new_register_dissector("wlan",                dissect_ieee80211,                    proto_wlan);
   register_dissector("wlan_withfcs",            dissect_ieee80211_withfcs,            proto_wlan);
   register_dissector("wlan_withoutfcs",         dissect_ieee80211_withoutfcs,         proto_wlan);
   register_dissector("wlan_fixed",              dissect_ieee80211_fixed,              proto_wlan);
   register_dissector("wlan_bsfc",               dissect_ieee80211_bsfc,               proto_wlan);
-  register_dissector("wlan_datapad",            dissect_ieee80211_datapad,            proto_wlan);
+  new_register_dissector("wlan_datapad",        dissect_ieee80211_datapad,            proto_wlan);
   register_dissector("wlan_datapad_withfcs",    dissect_ieee80211_datapad_withfcs,    proto_wlan);
   register_dissector("wlan_datapad_withoutfcs", dissect_ieee80211_datapad_withoutfcs, proto_wlan);
-  register_dissector("wlan_ht",                 dissect_ieee80211_ht,                 proto_wlan);
+  new_register_dissector("wlan_ht",             dissect_ieee80211_ht,                 proto_wlan);
 
   register_init_routine(wlan_defragment_init);
   register_init_routine(wlan_retransmit_init);
@@ -27145,8 +27158,9 @@ proto_reg_handoff_ieee80211(void)
 
   ieee80211_handle = find_dissector("wlan");
   dissector_add_uint("wtap_encap", WTAP_ENCAP_IEEE_802_11, ieee80211_handle);
+  dissector_add_uint("wtap_encap", WTAP_ENCAP_IEEE_802_11_WITH_RADIO, ieee80211_handle);
 
-  centrino_handle = create_dissector_handle( dissect_ieee80211_centrino, proto_wlan );
+  centrino_handle = new_create_dissector_handle( dissect_ieee80211_centrino, proto_wlan );
   dissector_add_uint("ethertype", ETHERTYPE_CENTRINO_PROMISC, centrino_handle);
 
   /* Register handoff to Aruba GRE */
diff --git a/epan/dissectors/packet-ppi.c b/epan/dissectors/packet-ppi.c
index c6ef8173a4..5541bcd779 100644
--- a/epan/dissectors/packet-ppi.c
+++ b/epan/dissectors/packet-ppi.c
@@ -333,6 +333,7 @@ static expert_field ei_ppi_invalid_length = EI_INIT;
 static dissector_handle_t ppi_handle;
 
 static dissector_handle_t data_handle;
+static dissector_handle_t ieee80211_handle;
 static dissector_handle_t ieee80211_ht_handle;
 static dissector_handle_t ppi_gps_handle, ppi_vector_handle, ppi_sensor_handle, ppi_antenna_handle;
 static dissector_handle_t ppi_fnet_handle;
@@ -476,7 +477,7 @@ add_ppi_field_header(tvbuff_t *tvb, proto_tree *tree, int *offset)
 
 /* XXX - The main dissection function in the 802.11 dissector has the same name. */
 static void
-dissect_80211_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, int data_len)
+dissect_80211_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, int data_len, struct ieee_802_11_phdr *phdr)
 {
     proto_tree  *ftree;
     proto_item  *ti;
@@ -497,9 +498,9 @@ dissect_80211_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int of
 
     common_flags = tvb_get_letohs(tvb, offset + 8);
     if (common_flags & DOT11_FLAG_HAVE_FCS)
-        pinfo->pseudo_header->ieee_802_11.fcs_len = 4;
+        phdr->fcs_len = 4;
     else
-        pinfo->pseudo_header->ieee_802_11.fcs_len = 0;
+        phdr->fcs_len = 0;
 
     csr = ptvcursor_new(ftree, tvb, offset);
 
@@ -752,6 +753,7 @@ dissect_ppi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
     guint          last_frame  = 0;
     gboolean       is_ht       = FALSE;
     gint len_remain, /*pad_len = 0,*/ ampdu_len = 0;
+    struct ieee_802_11_phdr phdr;
 
     col_set_str(pinfo->cinfo, COL_PROTOCOL, "PPI");
     col_clear(pinfo->cinfo, COL_INFO);
@@ -790,6 +792,11 @@ dissect_ppi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
     tot_len -= PPI_V0_HEADER_LEN;
     offset += 8;
 
+    /* We don't have any 802.11 metadata yet. */
+    phdr.fcs_len = -1;
+    phdr.decrypted = FALSE;
+    phdr.presence_flags = 0;
+
     while (tot_len > 0) {
         data_type = tvb_get_letohs(tvb, offset);
         data_len = tvb_get_letohs(tvb, offset + 2) + 4;
@@ -797,7 +804,8 @@ dissect_ppi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 
         switch (data_type) {
             case PPI_80211_COMMON:
-                dissect_80211_common(tvb, pinfo, ppi_tree, offset, data_len);
+                dissect_80211_common(tvb, pinfo, ppi_tree, offset, data_len,
+                    &phdr);
                 break;
 
             case PPI_80211N_MAC:
@@ -988,7 +996,7 @@ dissect_ppi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
                     add_new_data_source(pinfo, next_tvb, mpdu_str);
 
                     ampdu_tree = proto_tree_add_subtree(agg_tree, next_tvb, 0, -1, ett_ampdu_segment, NULL, mpdu_str);
-                    call_dissector(ieee80211_ht_handle, next_tvb, pinfo, ampdu_tree);
+                    call_dissector_with_data(ieee80211_ht_handle, next_tvb, pinfo, ampdu_tree, &phdr);
                 }
                 fd_head = fd_head->next;
             }
@@ -1004,9 +1012,26 @@ dissect_ppi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
     }
 
     next_tvb = tvb_new_subset_remaining(tvb, offset);
-    if (is_ht) { /* We didn't hit the reassembly code */
-        call_dissector(ieee80211_ht_handle, next_tvb, pinfo, tree);
+    /*
+     * You can't just call an arbitrary subdissector based on a
+     * LINKTYPE_ value, because they may expect a particular
+     * pseudo-header to be passed to them.
+     *
+     * So we look for LINKTYPE_IEEE802_11, which is 105, and, if
+     * that's what the LINKTYPE_ value is, pass it a pointer
+     * to a struct ieee_802_11_phdr; otherwise, we pass it
+     * a null pointer - if it actually matters, we need to
+     * construct the appropriate pseudo-header and pass that.
+     */
+    if (dlt == 105) {
+        /* LINKTYPE_IEEE802_11 */
+        if (is_ht) { /* We didn't hit the reassembly code */
+            call_dissector_with_data(ieee80211_ht_handle, next_tvb, pinfo, tree, &phdr);
+        } else {
+            call_dissector_with_data(ieee80211_handle, next_tvb, pinfo, tree, &phdr);
+        }
     } else {
+        /* Everything else.  This will pass a NULL data argument. */
         dissector_try_uint(wtap_encap_dissector_table,
             wtap_pcap_encap_to_wtap_encap(dlt), next_tvb, pinfo, tree);
     }
@@ -1376,6 +1401,7 @@ void
 proto_reg_handoff_ppi(void)
 {
     data_handle = find_dissector("data");
+    ieee80211_handle = find_dissector("wlan");
     ieee80211_ht_handle = find_dissector("wlan_ht");
     ppi_gps_handle = find_dissector("ppi_gps");
     ppi_vector_handle = find_dissector("ppi_vector");