Adding upstream version 4.2.2.upstream/4.2.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 747 insertions, 0 deletions

diff --git a/epan/dissectors/packet-clnp.c b/epan/dissectors/packet-clnp.c
new file mode 100644
index 00000000..5bd2a840
--- /dev/null
+++ b/epan/dissectors/packet-clnp.c
@@ -0,0 +1,747 @@
+/* packet-clnp.c
+ * Routines for ISO/OSI network protocol packet disassembly
+ *
+ * Laurent Deniel <laurent.deniel@free.fr>
+ * Ralf Schneider <Ralf.Schneider@t-online.de>
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "config.h"
+
+#include <epan/packet.h>
+#include <epan/prefs.h>
+#include <epan/reassemble.h>
+#include <epan/expert.h>
+#include <epan/nlpid.h>
+
+#include "packet-osi.h"
+#include "packet-osi-options.h"
+
+void proto_register_clnp(void);
+void proto_reg_handoff_clnp(void);
+
+/* protocols and fields */
+
+static int  proto_clnp         = -1;
+static gint ett_clnp           = -1;
+static gint ett_clnp_type      = -1;
+static gint ett_clnp_segments  = -1;
+static gint ett_clnp_segment   = -1;
+static gint ett_clnp_disc_pdu  = -1;
+
+static int hf_clnp_id          = -1;
+static int hf_clnp_length      = -1;
+static int hf_clnp_version     = -1;
+static int hf_clnp_ttl         = -1;
+static int hf_clnp_type        = -1;
+static int hf_clnp_cnf_segmentation         = -1;
+static int hf_clnp_cnf_more_segments        = -1;
+static int hf_clnp_cnf_report_error         = -1;
+static int hf_clnp_cnf_type    = -1;
+static int hf_clnp_pdu_length  = -1;
+static int hf_clnp_data_unit_identifier     = -1;
+static int hf_clnp_segment_offset           = -1;
+static int hf_clnp_total_length             = -1;
+static int hf_clnp_checksum    = -1;
+static int hf_clnp_checksum_status          = -1;
+static int hf_clnp_dest_length = -1;
+static int hf_clnp_dest        = -1;
+static int hf_clnp_src_length  = -1;
+static int hf_clnp_src         = -1;
+       int hf_clnp_atntt       = -1; /* as referenced in packet-osi-options.c */
+       int hf_clnp_atnsc       = -1; /* as referenced in packet-osi-options.c */
+static int hf_clnp_segments    = -1;
+static int hf_clnp_segment     = -1;
+static int hf_clnp_segment_overlap          = -1;
+static int hf_clnp_segment_overlap_conflict = -1;
+static int hf_clnp_segment_multiple_tails   = -1;
+static int hf_clnp_segment_too_long_segment = -1;
+static int hf_clnp_segment_error            = -1;
+static int hf_clnp_segment_count            = -1;
+static int hf_clnp_reassembled_in           = -1;
+static int hf_clnp_reassembled_length       = -1;
+
+static const fragment_items clnp_frag_items = {
+    &ett_clnp_segment,
+    &ett_clnp_segments,
+    &hf_clnp_segments,
+    &hf_clnp_segment,
+    &hf_clnp_segment_overlap,
+    &hf_clnp_segment_overlap_conflict,
+    &hf_clnp_segment_multiple_tails,
+    &hf_clnp_segment_too_long_segment,
+    &hf_clnp_segment_error,
+    &hf_clnp_segment_count,
+    &hf_clnp_reassembled_in,
+    &hf_clnp_reassembled_length,
+    /* Reassembled data field */
+    NULL,
+    "segments"
+};
+
+static expert_field ei_clnp_length = EI_INIT;
+static expert_field ei_clnp_checksum = EI_INIT;
+
+static dissector_handle_t clnp_handle;
+static dissector_handle_t ositp_handle;
+static dissector_handle_t ositp_inactive_handle;
+static dissector_handle_t idrp_handle;
+
+/*
+ * ISO 8473 OSI CLNP definition (see RFC994)
+ *
+ *            _________________________________
+ *           |           Fixed Part            |
+ *           |_________________________________|
+ *           |          Address Part           |
+ *           |_________________________________|
+ *           |   Segmentation Part (optional)  |
+ *           |_________________________________|
+ *           |     Options Part (optional)     |
+ *           |_________________________________|
+ *           |         Data (optional)         |
+ *           |_________________________________|
+ */
+
+#define ISO8473_V1  0x01    /* CLNP version 1 */
+
+/* Fixed part */
+
+/* Length of fixed part */
+#define FIXED_PART_LEN          9
+
+#define CNF_TYPE                0x1f
+#define CNF_ERR_OK              0x20
+#define CNF_MORE_SEGS           0x40
+#define CNF_SEG_OK              0x80
+
+#define DT_NPDU                 0x1C
+#define MD_NPDU                 0x1D
+#define ER_NPDU                 0x01
+#define ERQ_NPDU                0x1E
+#define ERP_NPDU                0x1F
+
+static const value_string npdu_type_abbrev_vals[] = {
+    { DT_NPDU,    "DT" },
+    { MD_NPDU,    "MD" },
+    { ER_NPDU,    "ER" },
+    { ERQ_NPDU,   "ERQ" },
+    { ERP_NPDU,   "ERP" },
+    { 0,          NULL }
+};
+
+static const value_string npdu_type_vals[] = {
+    { DT_NPDU,    "Data" },
+    { MD_NPDU,    "Multicast Data" },
+    { ER_NPDU,    "Error Report" },
+    { ERQ_NPDU,   "Echo Request" },
+    { ERP_NPDU,   "Echo Response" },
+    { 0,          NULL }
+};
+
+/* field position */
+
+#define P_CLNP_PROTO_ID         0
+#define P_CLNP_HDR_LEN          1
+#define P_CLNP_VERS             2
+#define P_CLNP_TTL              3
+#define P_CLNP_TYPE             4
+#define P_CLNP_SEGLEN           5
+#define P_CLNP_CKSUM            7
+#define P_CLNP_ADDRESS_PART     9
+
+/* Segmentation part */
+
+#define SEGMENTATION_PART_LEN   6
+
+struct clnp_segment {
+    gushort       cng_id;         /* data unit identifier */
+    gushort       cng_off;        /* segment offset */
+    gushort       cng_tot_len;    /* total length */
+};
+
+/* NSAP selector */
+
+#define NSEL_NET                0x00
+#define NSEL_NP                 0x20
+#define NSEL_TP                 0x21
+
+/* global variables */
+
+/* List of dissectors to call for CLNP packets */
+static heur_dissector_list_t clnp_heur_subdissector_list;
+
+/*
+ * Reassembly of CLNP.
+ */
+static reassembly_table clnp_reassembly_table;
+
+/* options */
+static guint tp_nsap_selector = NSEL_TP;
+static gboolean always_decode_transport = FALSE;
+static gboolean clnp_reassemble = TRUE;
+gboolean clnp_decode_atn_options = FALSE;
+
+/* function definitions */
+
+/*
+ *  CLNP part / main entry point
+*/
+
+static int
+dissect_clnp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+{
+    proto_tree     *clnp_tree;
+    proto_item     *ti, *ti_len = NULL, *ti_pdu_len = NULL, *ti_tot_len = NULL;
+    guint8          cnf_proto_id;
+    guint8          cnf_hdr_len;
+    guint8          cnf_vers;
+    guint8          cnf_ttl;
+    guint8          cnf_type;
+    char            flag_string[6+1];
+    const char     *pdu_type_string;
+    proto_tree     *type_tree;
+    guint16         segment_length;
+    guint16         du_id = 0;
+    guint16         segment_offset = 0;
+    guint16         total_length;
+    guint16         cnf_cksum;
+    gboolean        cksum_valid = TRUE;
+    int             offset;
+    guchar          src_len, dst_len, nsel, opt_len = 0;
+    guint           next_length;
+    proto_tree     *discpdu_tree;
+    gboolean        save_in_error_pkt;
+    fragment_head  *fd_head;
+    tvbuff_t       *next_tvb;
+    gboolean        update_col_info = TRUE;
+    gboolean        save_fragmented;
+    heur_dtbl_entry_t *hdtbl_entry;
+
+    col_set_str(pinfo->cinfo, COL_PROTOCOL, "CLNP");
+    col_clear(pinfo->cinfo, COL_INFO);
+
+    cnf_proto_id = tvb_get_guint8(tvb, P_CLNP_PROTO_ID);
+    if (cnf_proto_id == NLPID_NULL) {
+        col_set_str(pinfo->cinfo, COL_INFO, "Inactive subset");
+        ti = proto_tree_add_item(tree, proto_clnp, tvb, P_CLNP_PROTO_ID, 1, ENC_NA);
+        clnp_tree = proto_item_add_subtree(ti, ett_clnp);
+        proto_tree_add_uint_format(clnp_tree, hf_clnp_id, tvb, P_CLNP_PROTO_ID, 1,
+                cnf_proto_id, "Inactive subset");
+        next_tvb = tvb_new_subset_remaining(tvb, 1);
+        call_dissector(ositp_inactive_handle, next_tvb, pinfo, tree);
+        return tvb_captured_length(tvb);
+    }
+
+    /* return if version not known */
+    cnf_vers = tvb_get_guint8(tvb, P_CLNP_VERS);
+    if (cnf_vers != ISO8473_V1) {
+        call_data_dissector(tvb, pinfo, tree);
+        return tvb_captured_length(tvb);
+    }
+
+    /* fixed part decoding */
+    cnf_hdr_len = tvb_get_guint8(tvb, P_CLNP_HDR_LEN);
+
+    ti = proto_tree_add_item(tree, proto_clnp, tvb, 0, cnf_hdr_len, ENC_NA);
+    clnp_tree = proto_item_add_subtree(ti, ett_clnp);
+    proto_tree_add_uint(clnp_tree, hf_clnp_id, tvb, P_CLNP_PROTO_ID, 1,
+            cnf_proto_id);
+    ti_len = proto_tree_add_uint(clnp_tree, hf_clnp_length, tvb, P_CLNP_HDR_LEN, 1,
+            cnf_hdr_len);
+    if (cnf_hdr_len < FIXED_PART_LEN) {
+        /* Header length is less than the length of the fixed part of
+           the header. */
+        expert_add_info_format(pinfo, ti_len, &ei_clnp_length,
+                "Header length value < minimum length %u",
+                FIXED_PART_LEN);
+        return 2;
+    }
+    proto_tree_add_uint(clnp_tree, hf_clnp_version, tvb, P_CLNP_VERS, 1,
+                cnf_vers);
+    cnf_ttl = tvb_get_guint8(tvb, P_CLNP_TTL);
+    proto_tree_add_uint_format(clnp_tree, hf_clnp_ttl, tvb, P_CLNP_TTL, 1,
+            cnf_ttl,
+            "Holding Time : %u (%u.%u secs)",
+            cnf_ttl, cnf_ttl / 2, (cnf_ttl % 2) * 5);
+    cnf_type = tvb_get_guint8(tvb, P_CLNP_TYPE);
+    pdu_type_string = val_to_str(cnf_type & CNF_TYPE, npdu_type_abbrev_vals,
+            "Unknown (0x%02x)");
+    flag_string[0] = '\0';
+    if (cnf_type & CNF_SEG_OK)
+        (void) g_strlcat(flag_string, "S ", 7);
+    if (cnf_type & CNF_MORE_SEGS)
+        (void) g_strlcat(flag_string, "M ", 7);
+    if (cnf_type & CNF_ERR_OK)
+        (void) g_strlcat(flag_string, "E ", 7);
+    ti = proto_tree_add_uint_format(clnp_tree, hf_clnp_type, tvb, P_CLNP_TYPE, 1,
+            cnf_type,
+            "PDU Type     : 0x%02x (%s%s)",
+            cnf_type,
+            flag_string,
+            pdu_type_string);
+    type_tree = proto_item_add_subtree(ti, ett_clnp_type);
+    proto_tree_add_item(type_tree, hf_clnp_cnf_segmentation, tvb, P_CLNP_TYPE, 1, ENC_NA);
+    proto_tree_add_item(type_tree, hf_clnp_cnf_more_segments, tvb, P_CLNP_TYPE, 1, ENC_NA);
+    proto_tree_add_item(type_tree, hf_clnp_cnf_report_error, tvb, P_CLNP_TYPE, 1, ENC_NA);
+    proto_tree_add_item(type_tree, hf_clnp_cnf_type, tvb, P_CLNP_TYPE, 1, ENC_BIG_ENDIAN);
+
+    /* If we don't have the full header - i.e., not enough to see the
+       segmentation part and determine whether this datagram is segmented
+       or not - set the Info column now; we'll get an exception before
+       we set it otherwise. */
+
+    if (tvb_reported_length(tvb) < cnf_hdr_len) {
+        col_add_fstr(pinfo->cinfo, COL_INFO, "%s NPDU %s", pdu_type_string, flag_string);
+    }
+
+    segment_length = tvb_get_ntohs(tvb, P_CLNP_SEGLEN);
+    ti_pdu_len = proto_tree_add_uint(clnp_tree, hf_clnp_pdu_length, tvb, P_CLNP_SEGLEN, 2,
+            segment_length);
+    if (segment_length < cnf_hdr_len) {
+        /* Segment length is less than the header length. */
+        expert_add_info_format(pinfo, ti_pdu_len, &ei_clnp_length,
+                "PDU length < header length %u", cnf_hdr_len);
+        return 7;
+    }
+    cnf_cksum = tvb_get_ntohs(tvb, P_CLNP_CKSUM);
+    if (cnf_cksum == 0) {
+        /* No checksum present */
+        proto_tree_add_checksum(clnp_tree, tvb, P_CLNP_CKSUM, hf_clnp_checksum, hf_clnp_checksum_status, &ei_clnp_checksum, pinfo, 0, ENC_BIG_ENDIAN, PROTO_CHECKSUM_NOT_PRESENT);
+    } else {
+        guint32 c0 = 0, c1 = 0;
+
+        if (osi_calc_checksum(tvb, 0, cnf_hdr_len, &c0, &c1)) {
+            /* Successfully processed checksum, verify it */
+            proto_tree_add_checksum(clnp_tree, tvb, P_CLNP_CKSUM, hf_clnp_checksum, hf_clnp_checksum_status, &ei_clnp_checksum, pinfo, c0 | c1, ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY|PROTO_CHECKSUM_ZERO);
+            cksum_valid = (c0 | c1) ? FALSE : TRUE;
+        } else {
+            proto_tree_add_checksum(clnp_tree, tvb, P_CLNP_CKSUM, hf_clnp_checksum, hf_clnp_checksum_status, &ei_clnp_checksum, pinfo, 0, ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS);
+        }
+    }
+
+    opt_len = cnf_hdr_len;
+    opt_len -= FIXED_PART_LEN; /* Fixed part of Header */
+
+    /* address part */
+
+    offset = P_CLNP_ADDRESS_PART;
+    if (opt_len < 1) {
+        /* Header length is less than the minimum value in CLNP,
+           including the destination address length. */
+        expert_add_info_format(pinfo, ti_len, &ei_clnp_length,
+                "Header length value < %u",
+                FIXED_PART_LEN + 1);
+        return offset;
+    }
+    dst_len  = tvb_get_guint8(tvb, offset);
+    if (tree) {
+        proto_tree_add_uint(clnp_tree, hf_clnp_dest_length, tvb, offset, 1,
+                dst_len);
+    }
+    offset += 1;
+    opt_len -= 1;
+
+    if (opt_len < dst_len) {
+        /* Header length is less than the minimum value,
+           including the destination address length and the
+           destination address. */
+        expert_add_info_format(pinfo, ti_len, &ei_clnp_length,
+                "Header length value < %u",
+                FIXED_PART_LEN + 1 + dst_len);
+        return offset;
+    }
+    nsel     = tvb_get_guint8(tvb, offset + dst_len - 1);
+    set_address_tvb(&pinfo->net_dst, get_osi_address_type(), dst_len, tvb, offset);
+    copy_address_shallow(&pinfo->dst, &pinfo->net_dst);
+    proto_tree_add_bytes_format_value(clnp_tree, hf_clnp_dest, tvb, offset, dst_len,
+            NULL,
+            "%s",
+            print_nsap_net(pinfo->pool, tvb, offset, dst_len));
+    offset += dst_len;
+    opt_len -= dst_len;
+
+    if (opt_len < 1) {
+        /* Header length is less than the minimum value,
+           including the destination address length, the
+           destination address, and the source address length. */
+        expert_add_info_format(pinfo, ti_len, &ei_clnp_length,
+                "Header length value < %u",
+                FIXED_PART_LEN + 1 + dst_len + 1);
+        return offset;
+    }
+    src_len  = tvb_get_guint8(tvb, offset);
+    if (tree) {
+        proto_tree_add_uint(clnp_tree, hf_clnp_src_length, tvb,
+                offset, 1, src_len);
+    }
+    offset += 1;
+    opt_len -= 1;
+
+    if (opt_len < src_len) {
+        /* Header length is less than the minimum value,
+           including the destination address length, the
+           destination address, the source address length,
+           and the source address. */
+        expert_add_info_format(pinfo, ti_len, &ei_clnp_length,
+                "Header length value < %u",
+                FIXED_PART_LEN + 1 + dst_len + 1 + src_len);
+        return offset;
+    }
+    set_address_tvb(&pinfo->net_src, get_osi_address_type(), src_len, tvb, offset);
+    copy_address_shallow(&pinfo->src, &pinfo->net_src);
+    proto_tree_add_bytes_format_value(clnp_tree, hf_clnp_src, tvb, offset, src_len,
+            NULL,
+            "%s",
+            print_nsap_net(pinfo->pool, tvb, offset, src_len));
+    offset += src_len;
+    opt_len -= src_len;
+
+    /* Segmentation Part */
+
+    if (cnf_type & CNF_SEG_OK) {
+        if (opt_len < SEGMENTATION_PART_LEN) {
+            /* Header length is less than the minimum value,
+               including the destination address length, the
+               destination address, the source address length,
+               the source address, and the segmentation part. */
+            expert_add_info_format(pinfo, ti_len, &ei_clnp_length,
+                    "Header length value < %u",
+                    FIXED_PART_LEN + 1 + dst_len + 1 + SEGMENTATION_PART_LEN);
+            return offset;
+        }
+
+        du_id = tvb_get_ntohs(tvb, offset);
+        proto_tree_add_item(clnp_tree, hf_clnp_data_unit_identifier, tvb, offset, 2, ENC_BIG_ENDIAN);
+        segment_offset = tvb_get_ntohs(tvb, offset + 2);
+        proto_tree_add_item(clnp_tree, hf_clnp_segment_offset, tvb, offset + 2 , 2, ENC_BIG_ENDIAN);
+        total_length = tvb_get_ntohs(tvb, offset + 4);
+        ti_tot_len = proto_tree_add_item(clnp_tree, hf_clnp_total_length, tvb, offset + 4 , 2, ENC_BIG_ENDIAN);
+        if (total_length < segment_length) {
+            /* Reassembled length is less than the length of this segment. */
+            expert_add_info_format(pinfo, ti_tot_len, &ei_clnp_length,
+                    "Total length < segment length %u", segment_length);
+            return offset;
+        }
+        offset  += SEGMENTATION_PART_LEN;
+        opt_len -= SEGMENTATION_PART_LEN;
+    }
+
+    dissect_osi_options(opt_len, tvb, offset, clnp_tree, pinfo);
+
+    offset += opt_len;
+
+    /* If clnp_reassemble is on, this is a segment, we have all the
+     * data in the segment, and the checksum is valid, then just add the
+     * segment to the hashtable.
+     */
+    save_fragmented = pinfo->fragmented;
+    if (clnp_reassemble && (cnf_type & CNF_SEG_OK) &&
+            ((cnf_type & CNF_MORE_SEGS) || segment_offset != 0) &&
+            tvb_bytes_exist(tvb, offset, segment_length - cnf_hdr_len) &&
+            segment_length > cnf_hdr_len &&
+            cksum_valid != FALSE) {
+        fd_head = fragment_add_check(&clnp_reassembly_table,
+                tvb, offset, pinfo, du_id, NULL,
+                segment_offset, segment_length - cnf_hdr_len,
+                cnf_type & CNF_MORE_SEGS);
+
+        next_tvb = process_reassembled_data(tvb, offset, pinfo, "Reassembled CLNP",
+                fd_head, &clnp_frag_items, &update_col_info, clnp_tree);
+    } else {
+        /* If this is the first segment, dissect its contents, otherwise
+           just show it as a segment.
+
+           XXX - if we eventually don't save the reassembled contents of all
+           segmented datagrams, we may want to always reassemble. */
+        if ((cnf_type & CNF_SEG_OK) && segment_offset != 0) {
+            /* Not the first segment - don't dissect it. */
+            next_tvb = NULL;
+        } else {
+            /* First segment, or not segmented.  Dissect what we have here. */
+
+            /* Get a tvbuff for the payload.  Set its length to the segment
+               length, and flag it as a fragment, so going past the end
+               reports FragmentBoundsError, i.e. "there's data missing
+               because this isn't reassembled", not ReportedBoundsError,
+               i.e. "the dissector ran past the end of the packet, so the
+               packet must not have been constructed properly". */
+            next_tvb = tvb_new_subset_length(tvb, offset, segment_length - cnf_hdr_len);
+            tvb_set_fragment(next_tvb);
+
+            /*
+             * If this is the first segment, but not the only segment,
+             * tell the next protocol that.
+             */
+            if ((cnf_type & (CNF_SEG_OK|CNF_MORE_SEGS)) == (CNF_SEG_OK|CNF_MORE_SEGS))
+                pinfo->fragmented = TRUE;
+            else
+                pinfo->fragmented = FALSE;
+        }
+    }
+
+    if (next_tvb == NULL) {
+        /* Just show this as a segment. */
+        col_add_fstr(pinfo->cinfo, COL_INFO, "Fragmented %s NPDU %s(off=%u)",
+                pdu_type_string, flag_string, segment_offset);
+
+        /* As we haven't reassembled anything, we haven't changed "pi", so
+           we don't have to restore it. */
+        call_data_dissector(tvb_new_subset_remaining(tvb, offset), pinfo, tree);
+        pinfo->fragmented = save_fragmented;
+        return tvb_captured_length(tvb);
+    }
+
+    if (tvb_offset_exists(tvb, offset)) {
+        switch (cnf_type & CNF_TYPE) {
+
+            case DT_NPDU:
+            case MD_NPDU:
+                /* Continue with COTP if any data.
+                   XXX - if this isn't the first Derived PDU of a segmented Initial
+                   PDU, skip that? */
+
+                if (nsel==NSEL_NET && tvb_get_guint8(next_tvb, 0)==NLPID_ISO10747_IDRP) {
+                    if(call_dissector(idrp_handle, next_tvb, pinfo, tree) != 0) {
+                        pinfo->fragmented = save_fragmented;
+                        return tvb_captured_length(tvb);
+                    }
+                }
+                if (nsel == (guchar)tp_nsap_selector || always_decode_transport) {
+                    if (call_dissector(ositp_handle, next_tvb, pinfo, tree) != 0) {
+                        pinfo->fragmented = save_fragmented;
+                        return tvb_captured_length(tvb);       /* yes, it appears to be COTP or CLTP */
+                    }
+                }
+                if (dissector_try_heuristic(clnp_heur_subdissector_list, next_tvb,
+                            pinfo, tree, &hdtbl_entry, NULL)) {
+                    pinfo->fragmented = save_fragmented;
+                    return tvb_captured_length(tvb);       /* yes, it appears to be one of the protocols in the heuristic list */
+                }
+
+                break;
+
+            case ER_NPDU:
+                /* The payload is the header and "none, some, or all of the data
+                   part of the discarded PDU", i.e. it's like an ICMP error;
+                   dissect it as a CLNP PDU. */
+
+                col_add_fstr(pinfo->cinfo, COL_INFO, "%s NPDU %s", pdu_type_string, flag_string);
+                next_length = tvb_reported_length_remaining(tvb, offset);
+                if (next_length != 0) {
+                    /* We have payload; dissect it. */
+                    discpdu_tree = proto_tree_add_subtree(clnp_tree, tvb, offset, next_length,
+                            ett_clnp_disc_pdu, NULL, "Discarded PDU");
+
+                    /* Save the current value of the "we're inside an error packet"
+                       flag, and set that flag; subdissectors may treat packets
+                       that are the payload of error packets differently from
+                       "real" packets. */
+                    save_in_error_pkt = pinfo->flags.in_error_pkt;
+                    pinfo->flags.in_error_pkt = TRUE;
+
+                    call_dissector(clnp_handle, next_tvb, pinfo, discpdu_tree);
+
+                    /* Restore the "we're inside an error packet" flag. */
+                    pinfo->flags.in_error_pkt = save_in_error_pkt;
+                }
+                pinfo->fragmented = save_fragmented;
+                return tvb_captured_length(tvb);   /* we're done with this PDU */
+
+            case ERQ_NPDU:
+            case ERP_NPDU:
+                /* XXX - dissect this */
+                break;
+        }
+    }
+    col_add_fstr(pinfo->cinfo, COL_INFO, "%s NPDU %s", pdu_type_string, flag_string);
+    call_data_dissector(next_tvb, pinfo, tree);
+    pinfo->fragmented = save_fragmented;
+    return tvb_captured_length(tvb);
+} /* dissect_clnp */
+
+void
+proto_register_clnp(void)
+{
+    static hf_register_info hf[] = {
+        { &hf_clnp_id,
+            { "Network Layer Protocol Identifier", "clnp.nlpi", FT_UINT8, BASE_HEX,
+                VALS(nlpid_vals), 0x0, NULL, HFILL }},
+
+        { &hf_clnp_length,
+            { "HDR Length", "clnp.len",          FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
+
+        { &hf_clnp_version,
+            { "Version", "clnp.version",  FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
+
+        { &hf_clnp_ttl,
+            { "Holding Time", "clnp.ttl",        FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
+
+        { &hf_clnp_type,
+            { "PDU Type", "clnp.type",     FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
+
+        { &hf_clnp_cnf_segmentation,
+            { "Segmentation permitted", "clnp.cnf.segmentation", FT_BOOLEAN, 8, TFS(&tfs_yes_no), CNF_SEG_OK, NULL, HFILL }},
+
+        { &hf_clnp_cnf_more_segments,
+            { "More segments", "clnp.cnf.more_segments", FT_BOOLEAN, 8, TFS(&tfs_yes_no), CNF_MORE_SEGS, NULL, HFILL }},
+
+        { &hf_clnp_cnf_report_error,
+            { "Report error if PDU discarded", "clnp.cnf.report_error", FT_BOOLEAN, 8, TFS(&tfs_yes_no), CNF_ERR_OK, NULL, HFILL }},
+
+        { &hf_clnp_cnf_type,
+            { "Type", "clnp.cnf.type", FT_UINT8, BASE_DEC, VALS(npdu_type_vals), CNF_TYPE, NULL, HFILL }},
+
+        { &hf_clnp_pdu_length,
+            { "PDU length", "clnp.pdu.len",  FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL }},
+
+        { &hf_clnp_data_unit_identifier,
+            { "Data unit identifier", "clnp.data_unit_identifier",  FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL }},
+
+        { &hf_clnp_segment_offset,
+            { "Segment offset", "clnp.segment_offset",  FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL }},
+
+        { &hf_clnp_total_length,
+            { "Total length", "clnp.total_length",  FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL }},
+
+        { &hf_clnp_checksum,
+            { "Checksum", "clnp.checksum", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL }},
+
+        { &hf_clnp_checksum_status,
+            { "Checksum Status", "clnp.checksum.status", FT_UINT8, BASE_NONE, VALS(proto_checksum_vals), 0x0, NULL, HFILL }},
+
+        { &hf_clnp_dest_length,
+            { "DAL", "clnp.dsap.len", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
+
+        { &hf_clnp_dest,
+            { "DA", "clnp.dsap",     FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL }},
+
+        { &hf_clnp_src_length,
+            { "SAL", "clnp.ssap.len", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
+
+        { &hf_clnp_src,
+            { "SA", "clnp.ssap",     FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL }},
+
+        { &hf_clnp_atntt,
+            { "ATN traffic type", "clnp.atn.tt",     FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
+
+        { &hf_clnp_atnsc,
+            { "ATN security classification", "clnp.atn.sc",     FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
+
+        { &hf_clnp_segment_overlap,
+            { "Segment overlap", "clnp.segment.overlap", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+                "Segment overlaps with other segments", HFILL }},
+
+        { &hf_clnp_segment_overlap_conflict,
+            { "Conflicting data in segment overlap", "clnp.segment.overlap.conflict", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+                "Overlapping segments contained conflicting data", HFILL }},
+
+        { &hf_clnp_segment_multiple_tails,
+            { "Multiple tail segments found", "clnp.segment.multipletails", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+                "Several tails were found when reassembling the packet", HFILL }},
+
+        { &hf_clnp_segment_too_long_segment,
+            { "Segment too long", "clnp.segment.toolongsegment", FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+                "Segment contained data past end of packet", HFILL }},
+
+        { &hf_clnp_segment_error,
+            { "Reassembly error", "clnp.segment.error", FT_FRAMENUM, BASE_NONE, NULL, 0x0,
+                "Reassembly error due to illegal segments", HFILL }},
+
+        { &hf_clnp_segment_count,
+            { "Segment count", "clnp.segment.count", FT_UINT32, BASE_DEC, NULL, 0x0,
+                NULL, HFILL }},
+
+        { &hf_clnp_segment,
+            { "CLNP Segment", "clnp.segment", FT_FRAMENUM, BASE_NONE, NULL, 0x0,
+                NULL, HFILL }},
+
+        { &hf_clnp_segments,
+            { "CLNP Segments", "clnp.segments", FT_NONE, BASE_NONE, NULL, 0x0,
+                NULL, HFILL }},
+
+        { &hf_clnp_reassembled_in,
+            { "Reassembled CLNP in frame", "clnp.reassembled_in", FT_FRAMENUM, BASE_NONE, NULL, 0x0,
+                "This CLNP packet is reassembled in this frame", HFILL }},
+
+        { &hf_clnp_reassembled_length,
+            { "Reassembled CLNP length", "clnp.reassembled.length", FT_UINT32, BASE_DEC, NULL, 0x0,
+                "The total length of the reassembled payload", HFILL }}
+    };
+    static gint *ett[] = {
+        &ett_clnp,
+        &ett_clnp_type,
+        &ett_clnp_segments,
+        &ett_clnp_segment,
+        &ett_clnp_disc_pdu,
+    };
+
+    static ei_register_info ei[] = {
+        { &ei_clnp_length, { "clnp.len.bad", PI_MALFORMED, PI_ERROR, "Header length value bad", EXPFILL }},
+        { &ei_clnp_checksum, { "clnp.bad_checksum", PI_CHECKSUM, PI_ERROR, "Bad checksum", EXPFILL }},
+    };
+
+    module_t *clnp_module;
+    expert_module_t* expert_clnp;
+
+    proto_clnp = proto_register_protocol(PROTO_STRING_CLNP, "CLNP", "clnp");
+    proto_register_field_array(proto_clnp, hf, array_length(hf));
+    proto_register_subtree_array(ett, array_length(ett));
+    expert_clnp = expert_register_protocol(proto_clnp);
+    expert_register_field_array(expert_clnp, ei, array_length(ei));
+    clnp_handle = register_dissector("clnp", dissect_clnp, proto_clnp);
+    clnp_heur_subdissector_list = register_heur_dissector_list("clnp", proto_clnp);
+
+    reassembly_table_register(&clnp_reassembly_table,
+            &addresses_reassembly_table_functions);
+
+    register_osi_address_type();
+
+    clnp_module = prefs_register_protocol(proto_clnp, NULL);
+    prefs_register_uint_preference(clnp_module, "tp_nsap_selector",
+            "NSAP selector for Transport Protocol (last byte in hex)",
+            "NSAP selector for Transport Protocol (last byte in hex)",
+            16, &tp_nsap_selector);
+    prefs_register_bool_preference(clnp_module, "always_decode_transport",
+            "Always try to decode NSDU as transport PDUs",
+            "Always try to decode NSDU as transport PDUs",
+            &always_decode_transport);
+    prefs_register_bool_preference(clnp_module, "reassemble",
+            "Reassemble segmented CLNP datagrams",
+            "Whether segmented CLNP datagrams should be reassembled",
+            &clnp_reassemble);
+    prefs_register_bool_preference(clnp_module, "decode_atn_options",
+            "Decode ATN security label",
+            "Whether ATN security label should be decoded",
+            &clnp_decode_atn_options);
+}
+
+void
+proto_reg_handoff_clnp(void)
+{
+    ositp_handle = find_dissector_add_dependency("ositp", proto_clnp);
+    ositp_inactive_handle = find_dissector_add_dependency("ositp_inactive", proto_clnp);
+    idrp_handle = find_dissector_add_dependency("idrp", proto_clnp);
+
+    dissector_add_uint("osinl.incl", NLPID_ISO8473_CLNP, clnp_handle);
+    dissector_add_uint("osinl.incl", NLPID_NULL, clnp_handle); /* Inactive subset */
+    dissector_add_uint("x.25.spi", NLPID_ISO8473_CLNP, clnp_handle);
+}
+
+/*
+ * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
+ *
+ * Local variables:
+ * c-basic-offset: 4
+ * tab-width: 8
+ * indent-tabs-mode: nil
+ * End:
+ *
+ * vi: set shiftwidth=4 tabstop=8 expandtab:
+ * :indentSize=4:tabSize=8:noTabs=true:
+ */