Rename WTAP_ENCAP_ATM_SNIFFER to WTAP_ENCAP_ATM_PDUS, as it's not just

used for the DOS-based ATM Sniffer.  (That's not a great name, but I
couldn't think of a better one.)

Add a new WTAP_ENCAP_ATM_PDUS_UNTRUNCATED encapsulation type for capture
files where reassembled frames don't have trailers, such as the AAL5
trailer, chopped off.  That's what at least some versions of the
Windows-based ATM Sniffer appear to have.

Map the ATM capture file type for NetXRay captures to
WTAP_ENCAP_ATM_PDUS_UNTRUNCATED, and put in stuff to fill in what we've
reverse-engineered, so far, for the pseudo-header; there's more that
needs to be done on it, e.g. getting the channel, AAL type, and traffic
type (or inferring them if they're not in the packet header).

svn path=/trunk/; revision=6840

10 files changed, 170 insertions, 88 deletions

diff --git a/capture.c b/capture.c
index 462028a240..f515926a3a 100644
--- a/capture.c
+++ b/capture.c
@@ -1,7 +1,7 @@
 /* capture.c
  * Routines for packet capture windows
  *
- * $Id: capture.c,v 1.202 2003/01/01 03:51:02 guy Exp $
+ * $Id: capture.c,v 1.203 2003/01/03 06:45:42 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -2245,7 +2245,7 @@ capture_pcap_cb(guchar *user, const struct pcap_pkthdr *phdr,
     case WTAP_ENCAP_LOCALTALK:
       capture_llap(&ld->counts);
       break;
-    case WTAP_ENCAP_ATM_SNIFFER:
+    case WTAP_ENCAP_ATM_PDUS:
       capture_atm(&pseudo_header, pd, whdr.caplen, &ld->counts);
       break;
     case WTAP_ENCAP_IP_OVER_FC:
diff --git a/packet-atm.c b/packet-atm.c
index aac07e2e81..a08374e646 100644
--- a/packet-atm.c
+++ b/packet-atm.c
@@ -1,7 +1,7 @@
 /* packet-atm.c
  * Routines for ATM packet disassembly
  *
- * $Id: packet-atm.c,v 1.49 2002/08/28 21:00:07 jmayer Exp $
+ * $Id: packet-atm.c,v 1.50 2003/01/03 06:45:42 guy Exp $
  *
  * Ethereal - Network traffic analyzer
  * By Gerald Combs <gerald@ethereal.com>
@@ -782,10 +782,16 @@ capture_atm(const union wtap_pseudo_header *pseudo_header, const guchar *pd,
 }
 
 static void
-dissect_atm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+dissect_atm_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,
+    gboolean truncated)
 {
-  proto_tree   *atm_tree;
+
+  proto_tree   *atm_tree = NULL;
   proto_item   *ti;
+  tvbuff_t     *next_tvb;
+  guint        length, reported_length;
+  guint16      aal5_length;
+  int          pad_length;
 
   if (check_col(pinfo->cinfo, COL_PROTOCOL))
     col_set_str(pinfo->cinfo, COL_PROTOCOL, "ATM");
@@ -875,6 +881,14 @@ dissect_atm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
  		pinfo->pseudo_header->atm.channel);
       break;
     }
+  }
+
+  next_tvb = tvb;
+  if (truncated) {
+    /*
+     * The packet data does not include stuff such as the AAL5
+     * trailer.
+     */
     if (pinfo->pseudo_header->atm.cells != 0) {
       /*
        * If the cell count is 0, assume it means we don't know how
@@ -887,15 +901,51 @@ dissect_atm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
        * some other way of indicating whether we have the AAL5 trailer
        * information.
        */
-      proto_tree_add_text(atm_tree, tvb, 0, 0, "Cells: %u",
+      if (tree) {
+        proto_tree_add_text(atm_tree, tvb, 0, 0, "Cells: %u",
 		pinfo->pseudo_header->atm.cells);
-      if (pinfo->pseudo_header->atm.aal == AAL_5) {
-        proto_tree_add_text(atm_tree, tvb, 0, 0, "AAL5 U2U: %u",
+        if (pinfo->pseudo_header->atm.aal == AAL_5) {
+          proto_tree_add_text(atm_tree, tvb, 0, 0, "AAL5 U2U: %u",
 		pinfo->pseudo_header->atm.aal5t_u2u);
-        proto_tree_add_text(atm_tree, tvb, 0, 0, "AAL5 len: %u",
+          proto_tree_add_text(atm_tree, tvb, 0, 0, "AAL5 len: %u",
 		pinfo->pseudo_header->atm.aal5t_len);
-        proto_tree_add_text(atm_tree, tvb, 0, 0, "AAL5 checksum: 0x%08X",
+          proto_tree_add_text(atm_tree, tvb, 0, 0, "AAL5 checksum: 0x%08X",
 		pinfo->pseudo_header->atm.aal5t_chksum);
+	}
+      }
+    }
+  } else {
+    /*
+     * The packet data includes stuff such as the AAL5 trailer.
+     * If this is AAL5 or Signalling AAL traffic, process it,
+     * and then strip off the trailer.
+     */
+    if (pinfo->pseudo_header->atm.aal == AAL_5 ||
+        pinfo->pseudo_header->atm.aal == AAL_SIGNALLING) {
+      length = tvb_length(tvb);
+      reported_length = tvb_reported_length(tvb);
+      if (length >= reported_length) {
+        /*
+         * XXX - what if the packet is truncated?  Can that happen?
+         * What if you capture with Windows Sniffer on an ATM link
+	 * and tell it not to save the entire packet?  What happens
+	 * to the trailer?
+         */
+        aal5_length = tvb_get_ntohs(tvb, length - 6);
+        if (tree) {
+          pad_length = length - aal5_length - 8;
+          if (pad_length > 0) {
+            proto_tree_add_text(atm_tree, tvb, aal5_length, pad_length,
+		"Padding");
+          }
+          proto_tree_add_text(atm_tree, tvb, length - 8, 2, "AAL5 U2U: %u",
+		tvb_get_ntohs(tvb, length - 8));
+          proto_tree_add_text(atm_tree, tvb, length - 6, 2, "AAL5 len: %u",
+		aal5_length);
+          proto_tree_add_text(atm_tree, tvb, length - 4, 4, "AAL5 checksum: 0x%08X",
+		tvb_get_ntohl(tvb, length - 4));
+	}
+	next_tvb = tvb_new_subset(tvb, 0, aal5_length, aal5_length);
       }
     }
   }
@@ -903,7 +953,7 @@ dissect_atm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
   switch (pinfo->pseudo_header->atm.aal) {
 
   case AAL_SIGNALLING:
-    call_dissector(sscop_handle, tvb, pinfo, tree);
+    call_dissector(sscop_handle, next_tvb, pinfo, tree);
     break;
 
   case AAL_5:
@@ -913,21 +963,21 @@ dissect_atm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
       /* Dissect as WTAP_ENCAP_ATM_RFC1483 */
       /* The ATM iptrace capture that we have shows LLC at this point,
        * so that's what I'm calling */
-      call_dissector(llc_handle, tvb, pinfo, tree);
+      call_dissector(llc_handle, next_tvb, pinfo, tree);
       break;
 
     case TRAF_LANE:
-      call_dissector(lane_handle, tvb, pinfo, tree);
+      call_dissector(lane_handle, next_tvb, pinfo, tree);
       break;
 
     case TRAF_ILMI:
-      call_dissector(ilmi_handle, tvb, pinfo, tree);
+      call_dissector(ilmi_handle, next_tvb, pinfo, tree);
       break;
 
     default:
       if (tree) {
         /* Dump it as raw data. */
-        call_dissector(data_handle,tvb, pinfo, tree);
+        call_dissector(data_handle, next_tvb, pinfo, tree);
         break;
       }
     }
@@ -936,12 +986,24 @@ dissect_atm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
   default:
     if (tree) {
       /* Dump it as raw data.  (Is this a single cell?) */
-      call_dissector(data_handle,tvb, pinfo, tree);
+      call_dissector(data_handle, next_tvb, pinfo, tree);
     }
     break;
   }
 }
 
+static void
+dissect_atm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+  dissect_atm_common(tvb, pinfo, tree, TRUE);
+}
+
+static void
+dissect_atm_untruncated(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+  dissect_atm_common(tvb, pinfo, tree, FALSE);
+}
+
 void
 proto_register_atm(void)
 {
@@ -980,7 +1042,7 @@ proto_register_atm(void)
 void
 proto_reg_handoff_atm(void)
 {
-	dissector_handle_t atm_handle;
+	dissector_handle_t atm_handle, atm_untruncated_handle;
 
 	/*
 	 * Get handles for the Ethernet, Token Ring, LLC, SSCOP, LANE,
@@ -995,6 +1057,10 @@ proto_reg_handoff_atm(void)
 	data_handle = find_dissector("data");
 
 	atm_handle = create_dissector_handle(dissect_atm, proto_atm);
+	dissector_add("wtap_encap", WTAP_ENCAP_ATM_PDUS, atm_handle);
 
-	dissector_add("wtap_encap", WTAP_ENCAP_ATM_SNIFFER, atm_handle);
+	atm_untruncated_handle = create_dissector_handle(dissect_atm_untruncated,
+	    proto_atm);
+	dissector_add("wtap_encap", WTAP_ENCAP_ATM_PDUS_UNTRUNCATED,
+	    atm_untruncated_handle);
 }
diff --git a/wiretap/iptrace.c b/wiretap/iptrace.c
index a6526b55fc..9bb1a7aef7 100644
--- a/wiretap/iptrace.c
+++ b/wiretap/iptrace.c
@@ -1,6 +1,6 @@
 /* iptrace.c
  *
- * $Id: iptrace.c,v 1.45 2002/11/01 20:43:11 guy Exp $
+ * $Id: iptrace.c,v 1.46 2003/01/03 06:45:45 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
@@ -186,7 +186,7 @@ static gboolean iptrace_read_1_0(wtap *wth, int *err, long *data_offset)
 		return FALSE;
 	}
 
-	if (wth->phdr.pkt_encap == WTAP_ENCAP_ATM_SNIFFER) {
+	if (wth->phdr.pkt_encap == WTAP_ENCAP_ATM_PDUS) {
 		get_atm_pseudo_header(data_ptr, wth->phdr.caplen,
 		    &wth->pseudo_header, header);
 	}
@@ -253,7 +253,7 @@ static gboolean iptrace_seek_read_1_0(wtap *wth, long seek_off,
 		return FALSE;
 
 	/* Get the ATM pseudo-header, if this is ATM traffic. */
-	if (pkt_encap == WTAP_ENCAP_ATM_SNIFFER)
+	if (pkt_encap == WTAP_ENCAP_ATM_PDUS)
 		get_atm_pseudo_header(pd, packet_size, pseudo_header, header);
 
 	return TRUE;
@@ -369,7 +369,7 @@ static gboolean iptrace_read_2_0(wtap *wth, int *err, long *data_offset)
 		return FALSE;
 	}
 
-	if (wth->phdr.pkt_encap == WTAP_ENCAP_ATM_SNIFFER) {
+	if (wth->phdr.pkt_encap == WTAP_ENCAP_ATM_PDUS) {
 		get_atm_pseudo_header(data_ptr, wth->phdr.caplen,
 		    &wth->pseudo_header, header);
 	}
@@ -436,7 +436,7 @@ static gboolean iptrace_seek_read_2_0(wtap *wth, long seek_off,
 		return FALSE;
 
 	/* Get the ATM pseudo-header, if this is ATM traffic. */
-	if (pkt_encap == WTAP_ENCAP_ATM_SNIFFER)
+	if (pkt_encap == WTAP_ENCAP_ATM_PDUS)
 		get_atm_pseudo_header(pd, packet_size, pseudo_header, header);
 
 	return TRUE;
@@ -582,7 +582,7 @@ wtap_encap_ift(unsigned int  ift)
 /* 0x22 */	WTAP_ENCAP_UNKNOWN,	/* IFT_PARA */
 /* 0x23 */	WTAP_ENCAP_UNKNOWN,	/* IFT_ARCNET */
 /* 0x24 */	WTAP_ENCAP_UNKNOWN,	/* IFT_ARCNETPLUS */
-/* 0x25 */	WTAP_ENCAP_ATM_SNIFFER,	/* IFT_ATM */
+/* 0x25 */	WTAP_ENCAP_ATM_PDUS,	/* IFT_ATM */
 	};
 	#define NUM_IFT_ENCAPS (sizeof ift_encap / sizeof ift_encap[0])
 
diff --git a/wiretap/libpcap.c b/wiretap/libpcap.c
index d4235476fe..e7ce0f3935 100644
--- a/wiretap/libpcap.c
+++ b/wiretap/libpcap.c
@@ -1,6 +1,6 @@
 /* libpcap.c
  *
- * $Id: libpcap.c,v 1.86 2002/12/11 22:45:24 guy Exp $
+ * $Id: libpcap.c,v 1.87 2003/01/03 06:45:45 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
@@ -239,7 +239,7 @@ static const struct {
 	{ 119,		WTAP_ENCAP_PRISM_HEADER }, /* Prism monitor mode hdr */
 	{ 121,		WTAP_ENCAP_HHDLC },	/* HiPath HDLC */
 	{ 122,		WTAP_ENCAP_IP_OVER_FC },   /* RFC 2625 IP-over-FC */
-	{ 123,		WTAP_ENCAP_ATM_SNIFFER },  /* SunATM */
+	{ 123,		WTAP_ENCAP_ATM_PDUS },  /* SunATM */
 	{ 127,		WTAP_ENCAP_WLAN_HEADER },  /* 802.11 plus WLAN header */
 
 	/*
@@ -888,7 +888,7 @@ static gboolean libpcap_read(wtap *wth, int *err, long *data_offset)
 	 * the VCI; read them and generate the pseudo-header from
 	 * them.
 	 */
-	if (wth->file_encap == WTAP_ENCAP_ATM_SNIFFER) {
+	if (wth->file_encap == WTAP_ENCAP_ATM_PDUS) {
 		if (packet_size < sizeof (struct sunatm_hdr)) {
 			/*
 			 * Uh-oh, the packet isn't big enough to even
@@ -927,7 +927,7 @@ static gboolean libpcap_read(wtap *wth, int *err, long *data_offset)
 	 * If this is ATM LANE traffic, try to guess what type of LANE
 	 * traffic it is based on the packet contents.
 	 */
-	if (wth->file_encap == WTAP_ENCAP_ATM_SNIFFER &&
+	if (wth->file_encap == WTAP_ENCAP_ATM_PDUS &&
 	    wth->pseudo_header.atm.type == TRAF_LANE) {
 		atm_guess_lane_type(buffer_start_ptr(wth->frame_buffer),
 		    wth->phdr.caplen, &wth->pseudo_header);
@@ -943,7 +943,7 @@ libpcap_seek_read(wtap *wth, long seek_off,
 	if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
 		return FALSE;
 
-	if (wth->file_encap == WTAP_ENCAP_ATM_SNIFFER) {
+	if (wth->file_encap == WTAP_ENCAP_ATM_PDUS) {
 		if (!libpcap_read_atm_pseudoheader(wth->random_fh, pseudo_header,
 		    err)) {
 			/* Read error */
@@ -961,7 +961,7 @@ libpcap_seek_read(wtap *wth, long seek_off,
 	 * If this is ATM LANE traffic, try to guess what type of LANE
 	 * traffic it is based on the packet contents.
 	 */
-	if (wth->file_encap == WTAP_ENCAP_ATM_SNIFFER &&
+	if (wth->file_encap == WTAP_ENCAP_ATM_PDUS &&
 	    pseudo_header->atm.type == TRAF_LANE)
 		atm_guess_lane_type(pd, length, pseudo_header);
 	return TRUE;
@@ -1258,7 +1258,7 @@ wtap_process_pcap_packet(gint linktype, const struct pcap_pkthdr *phdr,
 	 * the VCI; read them and generate the pseudo-header from
 	 * them.
 	 */
-	if (linktype == WTAP_ENCAP_ATM_SNIFFER) {
+	if (linktype == WTAP_ENCAP_ATM_PDUS) {
 		if (whdr->caplen < sizeof (struct sunatm_hdr)) {
 			/*
 			 * Uh-oh, the packet isn't big enough to even
@@ -1392,7 +1392,7 @@ static gboolean libpcap_dump(wtap_dumper *wdh,
 	struct sunatm_hdr atm_hdr;
 	int atm_hdrsize;
 
-	if (wdh->encap == WTAP_ENCAP_ATM_SNIFFER)
+	if (wdh->encap == WTAP_ENCAP_ATM_PDUS)
 		atm_hdrsize = sizeof (struct sunatm_hdr);
 	else
 		atm_hdrsize = 0;
@@ -1470,7 +1470,7 @@ static gboolean libpcap_dump(wtap_dumper *wdh,
 	}
 	wdh->bytes_dumped += hdr_size;
 
-	if (wdh->encap == WTAP_ENCAP_ATM_SNIFFER) {
+	if (wdh->encap == WTAP_ENCAP_ATM_PDUS) {
 		/*
 		 * Write the ATM header.
 		 */
diff --git a/wiretap/netmon.c b/wiretap/netmon.c
index c0531a86c1..f812151703 100644
--- a/wiretap/netmon.c
+++ b/wiretap/netmon.c
@@ -1,6 +1,6 @@
 /* netmon.c
  *
- * $Id: netmon.c,v 1.61 2002/08/28 20:30:44 jmayer Exp $
+ * $Id: netmon.c,v 1.62 2003/01/03 06:45:45 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
@@ -128,7 +128,7 @@ int netmon_open(wtap *wth, int *err)
 		WTAP_ENCAP_ETHERNET,
 		WTAP_ENCAP_TOKEN_RING,
 		WTAP_ENCAP_FDDI_BITSWAPPED,
-		WTAP_ENCAP_ATM_SNIFFER,	/* NDIS WAN - this is what's used for ATM */
+		WTAP_ENCAP_ATM_PDUS,	/* NDIS WAN - this is what's used for ATM */
 		WTAP_ENCAP_UNKNOWN,	/* NDIS LocalTalk */
 		WTAP_ENCAP_UNKNOWN,	/* NDIS "DIX" - should not occur */
 		WTAP_ENCAP_UNKNOWN,	/* NDIS ARCNET raw */
@@ -392,7 +392,7 @@ static gboolean netmon_read(wtap *wth, int *err, long *data_offset)
 	 * and the VPI and VCI; read them and generate the pseudo-header
 	 * from them.
 	 */
-	if (wth->file_encap == WTAP_ENCAP_ATM_SNIFFER) {
+	if (wth->file_encap == WTAP_ENCAP_ATM_PDUS) {
 		if (packet_size < sizeof (struct netmon_atm_hdr)) {
 			/*
 			 * Uh-oh, the packet isn't big enough to even
@@ -445,7 +445,7 @@ static gboolean netmon_read(wtap *wth, int *err, long *data_offset)
 	 * Attempt to guess from the packet data, the VPI, and the VCI
 	 * information about the type of traffic.
 	 */
-	if (wth->file_encap == WTAP_ENCAP_ATM_SNIFFER) {
+	if (wth->file_encap == WTAP_ENCAP_ATM_PDUS) {
 		atm_guess_traffic_type(data_ptr, packet_size,
 		    &wth->pseudo_header);
 	}
@@ -460,7 +460,7 @@ netmon_seek_read(wtap *wth, long seek_off,
 	if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
 		return FALSE;
 
-	if (wth->file_encap == WTAP_ENCAP_ATM_SNIFFER) {
+	if (wth->file_encap == WTAP_ENCAP_ATM_PDUS) {
 		if (!netmon_read_atm_pseudoheader(wth->random_fh, pseudo_header,
 		    err)) {
 			/* Read error */
@@ -478,7 +478,7 @@ netmon_seek_read(wtap *wth, long seek_off,
 	 * Attempt to guess from the packet data, the VPI, and the VCI
 	 * information about the type of traffic.
 	 */
-	if (wth->file_encap == WTAP_ENCAP_ATM_SNIFFER)
+	if (wth->file_encap == WTAP_ENCAP_ATM_PDUS)
 		atm_guess_traffic_type(pd, length, pseudo_header);
 
 	return TRUE;
@@ -567,7 +567,7 @@ static const int wtap_encap[] = {
 	-1,		/* WTAP_ENCAP_ATM_RFC1483 -> unsupported */
 	-1,		/* WTAP_ENCAP_LINUX_ATM_CLIP -> unsupported */
 	-1,		/* WTAP_ENCAP_LAPB -> unsupported*/
-	4,		/* WTAP_ENCAP_ATM_SNIFFER -> NDIS WAN (*NOT* ATM!) */
+	4,		/* WTAP_ENCAP_ATM_PDUS -> NDIS WAN (*NOT* ATM!) */
 	-1		/* WTAP_ENCAP_NULL -> unsupported */
 };
 #define NUM_WTAP_ENCAPS (sizeof wtap_encap / sizeof wtap_encap[0])
@@ -645,7 +645,7 @@ static gboolean netmon_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
 		netmon->got_first_record_time = TRUE;
 	}
 
-	if (wdh->encap == WTAP_ENCAP_ATM_SNIFFER)
+	if (wdh->encap == WTAP_ENCAP_ATM_PDUS)
 		atm_hdrsize = sizeof (struct netmon_atm_hdr);
 	else
 		atm_hdrsize = 0;
@@ -696,7 +696,7 @@ static gboolean netmon_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
 		return FALSE;
 	}
 
-	if (wdh->encap == WTAP_ENCAP_ATM_SNIFFER) {
+	if (wdh->encap == WTAP_ENCAP_ATM_PDUS) {
 		/*
 		 * Write the ATM header.
 		 * We supply all-zero destination and source addresses.
diff --git a/wiretap/netxray.c b/wiretap/netxray.c
index c665f1cf10..69b6976f0e 100644
--- a/wiretap/netxray.c
+++ b/wiretap/netxray.c
@@ -1,6 +1,6 @@
 /* netxray.c
  *
- * $Id: netxray.c,v 1.63 2003/01/03 02:24:56 guy Exp $
+ * $Id: netxray.c,v 1.64 2003/01/03 06:45:45 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
@@ -177,12 +177,7 @@ int netxray_open(wtap *wth, int *err)
 		WTAP_ENCAP_UNKNOWN,	/* "DIX" - should not occur */
 		WTAP_ENCAP_UNKNOWN,	/* ARCNET raw */
 		WTAP_ENCAP_UNKNOWN,	/* ARCNET 878.2 */
-		/*
-		 * XXX - not all ATM captures have LLC-encapsulated frames
-		 * in them; there's probably something hidden in the
-		 * per-packet header giving the traffic type.
-		 */
-		WTAP_ENCAP_ATM_RFC1483,	/* ATM */
+		WTAP_ENCAP_ATM_PDUS_UNTRUNCATED,	/* ATM */
 		WTAP_ENCAP_IEEE_802_11_WITH_RADIO,
 					/* Wireless WAN with radio information */
 		WTAP_ENCAP_UNKNOWN	/* IrDA */
@@ -549,6 +544,23 @@ netxray_set_pseudo_header(wtap *wth, union wtap_pseudo_header *pseudo_header,
 			pseudo_header->isdn.channel =
 			    hdr->hdr_2_x.xxx[13] & 0x1F;
 			break;
+
+		case WTAP_ENCAP_ATM_PDUS_UNTRUNCATED:
+			pseudo_header->atm.aal = AAL_5;		/* XXX */
+			pseudo_header->atm.type = TRAF_LLCMX;	/* XXX */
+			pseudo_header->atm.subtype = TRAF_ST_UNKNOWN;	/* XXX */
+			pseudo_header->atm.vpi = hdr->hdr_2_x.xxx[11];
+			pseudo_header->atm.vci = pletohs(&hdr->hdr_2_x.xxx[12]);
+			pseudo_header->atm.channel = 0;		/* XXX */
+			pseudo_header->atm.cells = 0;
+
+			if (pseudo_header->atm.vpi == 0) {
+				if (pseudo_header->atm.vci == 5)
+					pseudo_header->atm.aal = AAL_SIGNALLING;
+				else if (pseudo_header->atm.vci == 16)
+					pseudo_header->atm.type = TRAF_ILMI;
+			}
+			break;
 		}
 	}
 }
@@ -590,7 +602,7 @@ static const int wtap_encap[] = {
     -1,		/* WTAP_ENCAP_ATM_RFC1483 -> unsupported */
     -1,		/* WTAP_ENCAP_LINUX_ATM_CLIP -> unsupported */
     -1,		/* WTAP_ENCAP_LAPB -> unsupported */
-    -1,		/* WTAP_ENCAP_ATM_SNIFFER -> unsupported */
+    -1,		/* WTAP_ENCAP_ATM_PDUS_UNTRUNCATED -> unsupported */
     -1		/* WTAP_ENCAP_NULL -> unsupported */
 };
 #define NUM_WTAP_ENCAPS (sizeof wtap_encap / sizeof wtap_encap[0])
diff --git a/wiretap/ngsniffer.c b/wiretap/ngsniffer.c
index ca88a4324a..3483fcf076 100644
--- a/wiretap/ngsniffer.c
+++ b/wiretap/ngsniffer.c
@@ -1,6 +1,6 @@
 /* ngsniffer.c
  *
- * $Id: ngsniffer.c,v 1.95 2002/12/20 22:30:15 guy Exp $
+ * $Id: ngsniffer.c,v 1.96 2003/01/03 06:45:45 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
@@ -406,7 +406,7 @@ int ngsniffer_open(wtap *wth, int *err)
 		WTAP_ENCAP_PER_PACKET,	/* Internetwork analyzer (synchronous) */
 		WTAP_ENCAP_PER_PACKET,	/* Internetwork analyzer (asynchronous) */
 		WTAP_ENCAP_FDDI_BITSWAPPED,
-		WTAP_ENCAP_ATM_SNIFFER
+		WTAP_ENCAP_ATM_PDUS
 	};
 	#define NUM_NGSNIFF_ENCAPS (sizeof sniffer_encap / sizeof sniffer_encap[0])
 	gboolean is_router;
@@ -540,7 +540,7 @@ int ngsniffer_open(wtap *wth, int *err)
 	wth->snapshot_length = 0;	/* not available in header, only in frame */
 	wth->capture.ngsniffer->timeunit = Usec[version.timeunit];
 	wth->capture.ngsniffer->is_atm =
-	    (wth->file_encap == WTAP_ENCAP_ATM_SNIFFER);
+	    (wth->file_encap == WTAP_ENCAP_ATM_PDUS);
 	wth->capture.ngsniffer->is_router = is_router;
 
 	/* Get capture start time */
@@ -1685,7 +1685,7 @@ static const int wtap_encap[] = {
     -1,		/* WTAP_ENCAP_ATM_RFC1483 */
     -1,		/* WTAP_ENCAP_LINUX_ATM_CLIP */
     7,		/* WTAP_ENCAP_LAPB -> Internetwork analyzer (synchronous) */
-    -1,		/* WTAP_ENCAP_ATM_SNIFFER */
+    -1,		/* WTAP_ENCAP_ATM_PDUS */
     -1,		/* WTAP_ENCAP_NULL -> unsupported */
     -1,		/* WTAP_ENCAP_ASCEND -> unsupported */
     -1,		/* WTAP_ENCAP_ISDN -> unsupported */
diff --git a/wiretap/snoop.c b/wiretap/snoop.c
index ab3d2da9c9..709ab99355 100644
--- a/wiretap/snoop.c
+++ b/wiretap/snoop.c
@@ -1,6 +1,6 @@
 /* snoop.c
  *
- * $Id: snoop.c,v 1.58 2002/12/05 22:33:11 guy Exp $
+ * $Id: snoop.c,v 1.59 2003/01/03 06:45:45 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
@@ -172,7 +172,7 @@ int snoop_open(wtap *wth, int *err)
 		WTAP_ENCAP_UNKNOWN,	/* not defined in "dlpi.h" */
 		WTAP_ENCAP_IP_OVER_FC,	/* Fibre Channel */
 		WTAP_ENCAP_UNKNOWN,	/* ATM */
-		WTAP_ENCAP_ATM_SNIFFER,	/* ATM Classical IP */
+		WTAP_ENCAP_ATM_PDUS,	/* ATM Classical IP */
 		WTAP_ENCAP_UNKNOWN,	/* X.25 LAPB */
 		WTAP_ENCAP_UNKNOWN,	/* ISDN */
 		WTAP_ENCAP_UNKNOWN,	/* HIPPI */
@@ -401,7 +401,7 @@ static gboolean snoop_read(wtap *wth, int *err, long *data_offset)
 	 * the VCI; read them and generate the pseudo-header from
 	 * them.
 	 */
-	if (wth->file_encap == WTAP_ENCAP_ATM_SNIFFER) {
+	if (wth->file_encap == WTAP_ENCAP_ATM_PDUS) {
 		if (packet_size < sizeof (struct snoop_atm_hdr)) {
 			/*
 			 * Uh-oh, the packet isn't big enough to even
@@ -441,7 +441,7 @@ static gboolean snoop_read(wtap *wth, int *err, long *data_offset)
 	 * If this is ATM LANE traffic, try to guess what type of LANE
 	 * traffic it is based on the packet contents.
 	 */
-	if (wth->file_encap == WTAP_ENCAP_ATM_SNIFFER &&
+	if (wth->file_encap == WTAP_ENCAP_ATM_PDUS &&
 	    wth->pseudo_header.atm.type == TRAF_LANE) {
 		atm_guess_lane_type(buffer_start_ptr(wth->frame_buffer),
 		    wth->phdr.caplen, &wth->pseudo_header);
@@ -481,7 +481,7 @@ snoop_seek_read(wtap *wth, long seek_off,
 	if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
 		return FALSE;
 
-	if (wth->file_encap == WTAP_ENCAP_ATM_SNIFFER) {
+	if (wth->file_encap == WTAP_ENCAP_ATM_PDUS) {
 		if (!snoop_read_atm_pseudoheader(wth->random_fh, pseudo_header,
 		    err)) {
 			/* Read error */
@@ -499,7 +499,7 @@ snoop_seek_read(wtap *wth, long seek_off,
 	 * If this is ATM LANE traffic, try to guess what type of LANE
 	 * traffic it is based on the packet contents.
 	 */
-	if (wth->file_encap == WTAP_ENCAP_ATM_SNIFFER &&
+	if (wth->file_encap == WTAP_ENCAP_ATM_PDUS &&
 	    pseudo_header->atm.type == TRAF_LANE)
 		atm_guess_lane_type(pd, length, pseudo_header);
 	return TRUE;
@@ -627,7 +627,7 @@ static const int wtap_encap[] = {
 	-1,		/* WTAP_ENCAP_ATM_RFC1483 -> unsupported */
 	-1,		/* WTAP_ENCAP_LINUX_ATM_CLIP -> unsupported */
 	-1,		/* WTAP_ENCAP_LAPB -> unsupported*/
-	0x12,		/* WTAP_ENCAP_ATM_SNIFFER -> DL_IPATM */
+	0x12,		/* WTAP_ENCAP_ATM_PDUS -> DL_IPATM */
 	-1		/* WTAP_ENCAP_NULL -> unsupported */
 };
 #define NUM_WTAP_ENCAPS (sizeof wtap_encap / sizeof wtap_encap[0])
@@ -697,7 +697,7 @@ static gboolean snoop_dump(wtap_dumper *wdh,
 	struct snoop_atm_hdr atm_hdr;
 	int atm_hdrsize;
 
-	if (wdh->encap == WTAP_ENCAP_ATM_SNIFFER)
+	if (wdh->encap == WTAP_ENCAP_ATM_PDUS)
 		atm_hdrsize = sizeof (struct snoop_atm_hdr);
 	else
 		atm_hdrsize = 0;
@@ -724,7 +724,7 @@ static gboolean snoop_dump(wtap_dumper *wdh,
 		return FALSE;
 	}
 
-	if (wdh->encap == WTAP_ENCAP_ATM_SNIFFER) {
+	if (wdh->encap == WTAP_ENCAP_ATM_PDUS) {
 		/*
 		 * Write the ATM header.
 		 */
diff --git a/wiretap/wtap.c b/wiretap/wtap.c
index 74f0664f2c..0c5351ab65 100644
--- a/wiretap/wtap.c
+++ b/wiretap/wtap.c
@@ -1,6 +1,6 @@
 /* wtap.c
  *
- * $Id: wtap.c,v 1.75 2002/12/20 21:59:33 guy Exp $
+ * $Id: wtap.c,v 1.76 2003/01/03 06:45:45 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
@@ -95,8 +95,11 @@ static const struct encap_type_info {
 	/* WTAP_ENCAP_LAPB */
 	{ "LAPB", "lapb" },
 
-	/* WTAP_ENCAP_ATM_SNIFFER */
-	{ "ATM Sniffer", "atm-sniffer" },
+	/* WTAP_ENCAP_ATM_PDUS */
+	{ "ATM PDUs", "atm-pdus" },
+
+	/* WTAP_ENCAP_ATM_PDUS_UNTRUNCATED */
+	{ "ATM PDUs - untruncated", "atm-pdus-untruncated" },
 
 	/* WTAP_ENCAP_NULL */
 	{ "NULL", "null" },
diff --git a/wiretap/wtap.h b/wiretap/wtap.h
index ed8fd85208..8dc1b1f923 100644
--- a/wiretap/wtap.h
+++ b/wiretap/wtap.h
@@ -1,6 +1,6 @@
 /* wtap.h
  *
- * $Id: wtap.h,v 1.127 2002/12/20 05:40:52 sharpe Exp $
+ * $Id: wtap.h,v 1.128 2003/01/03 06:45:45 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
@@ -101,29 +101,30 @@
 #define WTAP_ENCAP_ATM_RFC1483			9
 #define WTAP_ENCAP_LINUX_ATM_CLIP		10
 #define WTAP_ENCAP_LAPB				11
-#define WTAP_ENCAP_ATM_SNIFFER			12
-#define WTAP_ENCAP_NULL				13
-#define WTAP_ENCAP_ASCEND			14
-#define WTAP_ENCAP_ISDN				15
-#define WTAP_ENCAP_IP_OVER_FC			16
-#define WTAP_ENCAP_PPP_WITH_PHDR		17
-#define WTAP_ENCAP_IEEE_802_11			18
-#define WTAP_ENCAP_IEEE_802_11_WITH_RADIO	19
-#define WTAP_ENCAP_SLL				20
-#define WTAP_ENCAP_FRELAY			21
-#define WTAP_ENCAP_CHDLC			22
-#define WTAP_ENCAP_CISCO_IOS			23
-#define WTAP_ENCAP_LOCALTALK			24
-#define WTAP_ENCAP_PRISM_HEADER			25
-#define WTAP_ENCAP_PFLOG			26
-#define WTAP_ENCAP_HHDLC			27
-#define WTAP_ENCAP_DOCSIS			28
-#define WTAP_ENCAP_COSINE			29
-#define WTAP_ENCAP_WLAN_HEADER			30
-#define WTAP_ENCAP_WFLEET_HDLC                  31
+#define WTAP_ENCAP_ATM_PDUS			12
+#define WTAP_ENCAP_ATM_PDUS_UNTRUNCATED		13
+#define WTAP_ENCAP_NULL				14
+#define WTAP_ENCAP_ASCEND			15
+#define WTAP_ENCAP_ISDN				16
+#define WTAP_ENCAP_IP_OVER_FC			17
+#define WTAP_ENCAP_PPP_WITH_PHDR		18
+#define WTAP_ENCAP_IEEE_802_11			19
+#define WTAP_ENCAP_IEEE_802_11_WITH_RADIO	20
+#define WTAP_ENCAP_SLL				21
+#define WTAP_ENCAP_FRELAY			22
+#define WTAP_ENCAP_CHDLC			23
+#define WTAP_ENCAP_CISCO_IOS			24
+#define WTAP_ENCAP_LOCALTALK			25
+#define WTAP_ENCAP_PRISM_HEADER			26
+#define WTAP_ENCAP_PFLOG			27
+#define WTAP_ENCAP_HHDLC			28
+#define WTAP_ENCAP_DOCSIS			29
+#define WTAP_ENCAP_COSINE			30
+#define WTAP_ENCAP_WLAN_HEADER			31
+#define WTAP_ENCAP_WFLEET_HDLC                  32
 
 /* last WTAP_ENCAP_ value + 1 */
-#define WTAP_NUM_ENCAP_TYPES			32
+#define WTAP_NUM_ENCAP_TYPES			33
 
 /* File types that can be read by wiretap.
    We support writing some many of these file types, too, so we