wireshark: update SMSCB dissector patch

Now factored out to its own dissector module, and supporting
message block reassembly.

Signed-off-by: Alex Badea <vamposdecampos@gmail.com>

1 files changed, 470 insertions, 211 deletions

diff --git a/src/wireshark/smscb.patch b/src/wireshark/smscb.patch
index 4ac09527..6929c71c 100644
--- a/src/wireshark/smscb.patch
+++ b/src/wireshark/smscb.patch
@@ -1,248 +1,507 @@
-From 8ab33ab3f2de22f83df1cd45ae9a38254dc76400 Mon Sep 17 00:00:00 2001
-From: Alex Badea <vamposdecampos@gmail.com>
-Date: Sun, 21 Nov 2010 22:19:58 +0200
-Subject: [RFC][PATCH wireshark] packet-lapdm: dissect CBS payloads
+Wireshark patch for SMSCB dissection support in LAPDm
 
-Hack dissection of Cell Broadcast Service into LAPDm.  First-Block payloads
-are also dissected directly.
----
- packet-lapdm.c |  164 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
- 1 file changed, 163 insertions(+), 1 deletion(-)
+Create a new gsm_smscb dissector module for SMSCB as defined in GSM TS
+04.12.  Call it from packet-lapdm when the Link Protocol Discriminator
+has the value "0 1".
 
-diff --git a/epan/dissectors/packet-lapdm.c b/epan/dissectors/packet-lapdm.c
-index dbeac85..e1d67b4 100644
---- a/epan/dissectors/packet-lapdm.c
-+++ b/epan/dissectors/packet-lapdm.c
-@@ -61,12 +61,25 @@
- #include <epan/xdlc.h>
- #include <epan/reassemble.h>
- 
+The dissector supports reassembly of SMSCB Message blocks.  Schedule
+block reassmebly or dissection is not yet implemented.
+
+Signed-off-by: Alex Badea <vamposdecampos@gmail.com>
+
+ Makefile.common    |    1 
+ packet-gsm_smscb.c |  404 +++++++++++++++++++++++++++++++++++++++++++++++++++++
+ packet-lapdm.c     |   18 +-
+ 3 files changed, 420 insertions(+), 3 deletions(-)
+
+diff --git a/epan/dissectors/Makefile.common b/epan/dissectors/Makefile.common
+index 1c1e60b..86bc856 100644
+--- a/epan/dissectors/Makefile.common
++++ b/epan/dissectors/Makefile.common
+@@ -500,6 +500,7 @@ DISSECTOR_SRC = \
+ 	packet-gsm_bssmap_le.c	\
+ 	packet-gsm_sms.c	\
+ 	packet-gsm_sms_ud.c	\
++	packet-gsm_smscb.c	\
+ 	packet-gsm_um.c		\
+ 	packet-gsmtap.c		\
+ 	packet-gssapi.c		\
+diff --git a/epan/dissectors/packet-gsm_smscb.c b/epan/dissectors/packet-gsm_smscb.c
+new file mode 100644
+index 0000000..12b98f9
+--- /dev/null
++++ b/epan/dissectors/packet-gsm_smscb.c
+@@ -0,0 +1,404 @@
++/* packet-gsm_smscb.c
++ * Routines for GSM SMSCB (GSM 04.12) dissection
++ * Copyright 2010, Alex Badea <vamposdecampos@gmail.com>
++ *
++ * $Id$
++ *
++ * Wireshark - Network traffic analyzer
++ * By Gerald Combs <gerald@wireshark.org>
++ * Copyright 1998 Gerald Combs
++ *
++ * Copied from WHATEVER_FILE_YOU_USED (where "WHATEVER_FILE_YOU_USED"
++ * is a dissector file; if you just copied this from README.developer,
++ * don't bother with the "Copied from" - you don't even need to put
++ * in a "Copied from" if you copied an existing dissector, especially
++ * if the bulk of the code in the new dissector is your code)
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License as published by
++ * the Free Software Foundation; either version 2 of the License, or
++ * (at your option) any later version.
++ *
++ * This program is distributed in the hope that it will be useful,
++ * but WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
++ * GNU General Public License for more details.
++ *
++ * You should have received a copy of the GNU General Public License along
++ * with this program; if not, write to the Free Software Foundation, Inc.,
++ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
++ */
++
++#ifdef HAVE_CONFIG_H
++# include "config.h"
++#endif
++
++#include <glib.h>
++
++#include <epan/packet.h>
++#include <epan/prefs.h>
++#include <epan/reassemble.h>
 +#include <epan/asn1.h>
 +#include "packet-gsm_map.h"
 +#include "packet-gsm_sms.h"
 +
- static int proto_lapdm = -1;
- static int hf_lapdm_address = -1;
- static int hf_lapdm_ea = -1;
- static int hf_lapdm_cr = -1;
- static int hf_lapdm_sapi = -1;
- static int hf_lapdm_lpd = -1;
-+static int hf_lapdm_cb_lb = -1;
-+static int hf_lapdm_cb_seq = -1;
-+static int hf_lapdm_cbs_serial_gs = -1;
-+static int hf_lapdm_cbs_serial_mcode = -1;
-+static int hf_lapdm_cbs_serial_updnum = -1;
-+static int hf_lapdm_cbs_msgid = -1;
-+static int hf_lapdm_cbs_page_num = -1;
-+static int hf_lapdm_cbs_page_cnt = -1;
-+static int hf_lapdm_cbs_content = -1;
- 
- static int hf_lapdm_control = -1;
- static int hf_lapdm_n_r = -1;
-@@ -103,6 +116,8 @@ static gint ett_lapdm_control = -1;
- static gint ett_lapdm_length = -1;
- static gint ett_lapdm_fragment = -1;
- static gint ett_lapdm_fragments = -1;
-+static gint ett_lapdm_cbs_serial = -1;
-+static gint ett_lapdm_cbs_dcs = -1;
- 
- static GHashTable *lapdm_fragment_table = NULL;
- static GHashTable *lapdm_reassembled_table = NULL;
-@@ -121,6 +136,12 @@ static gboolean reassemble_lapdm = TRUE;
- #define	LAPDM_CR		0x02	/* Command/Response bit */
- #define	LAPDM_EA		0x01	/* First Address Extension bit */
- #define	LAPDM_LPD		0x60	/* Link Protocol Discriminator */
-+#define	LAPDM_LPD_CB		0x20	/* Cell Broadcast LPD */
-+#define	LAPDM_CB_LB		0x10	/* Cell Broadcast Last Bit */
-+#define	LAPDM_CB_SEQ		0x0f	/* Cell Broadcast sequence number */
-+#define LAPDM_CBS_SERIAL_GS	0xc0	/* CBS Serial Number - Geographical Scope */
-+#define LAPDM_CBS_SERIAL_MCODE	0x3ffc	/* CBS Serial Number - Message Code */
-+#define LAPDM_CBS_SERIAL_UPDNUM	0x03	/* CBS Serial Number - Update Number */
- 
- /*
-  * Bits in the length field.
-@@ -132,6 +153,7 @@ static gboolean reassemble_lapdm = TRUE;
- #define	LAPDM_LEN_SHIFT		2
- 
- #define LAPDM_HEADER_LEN 3
-+#define LAPDM_CB_HEADER_LEN 1
- 
- #define LAPDM_SAPI_RR_CC_MM	0
- #define LAPDM_SAPI_SMS		3
-@@ -179,6 +201,33 @@ static const value_string lapdm_el_vals[] = {
-     { 0,		NULL }
- };
- 
++static gint proto_gsm_smscb = -1;
++static gint hf_smscb_addr = -1;
++static gint hf_smscb_addr_lb = -1;
++static gint hf_smscb_addr_seq = -1;
++static gint hf_smscb_serial_gs = -1;
++static gint hf_smscb_serial_mcode = -1;
++static gint hf_smscb_serial_updnum = -1;
++static gint hf_smscb_page_num = -1;
++static gint hf_smscb_page_cnt = -1;
++static gint hf_smscb_msgid = -1;
++static gint hf_smscb_content = -1;
++static gint hf_smscb_fragments = -1;
++static gint hf_smscb_fragment = -1;
++static gint hf_smscb_fragment_overlap = -1;
++static gint hf_smscb_fragment_overlap_conflicts = -1;
++static gint hf_smscb_fragment_multiple_tails = -1;
++static gint hf_smscb_fragment_too_long_fragment = -1;
++static gint hf_smscb_fragment_error = -1;
++static gint hf_smscb_reassembled_in = -1;
++static gint hf_smscb_reassembled_length = -1;
++
++static gint ett_smscb = -1;
++static gint ett_smscb_addr = -1;
++static gint ett_smscb_dcs = -1;
++static gint ett_smscb_fragment = -1;
++static gint ett_smscb_fragments = -1;
++
++static GHashTable *smscb_fragment_table = NULL;
++static GHashTable *smscb_reassembled_table = NULL;
++
++static gboolean reassemble_smscb = TRUE;
++
++static dissector_handle_t data_handle;
++
++#define SMSCB_HDR_MINLEN	1
++
++/*
++ * Bits in the address field.
++ */
++#define	SMSCB_ADDR_LB		0x10	/* Address Last Bit */
++#define	SMSCB_ADDR_SEQ		0x0f	/* Address sequence number */
++#define	SMSCB_SERIAL_GS		0xc0	/* CBS Serial Number - Geographical Scope */
++#define	SMSCB_SERIAL_MCODE	0x3ffc	/* CBS Serial Number - Message Code */
++#define	SMSCB_SERIAL_UPDNUM	0x03	/* CBS Serial Number - Update Number */
++#define	SMSCB_PAGE_NUM		0xf0	/* Page number */
++#define	SMSCB_PAGE_CNT		0x0f	/* Page total count */
++
++#define SMSCB_SEQ_LAST		3
++
 +/* 04.12 section 3.3.1 */
-+static const value_string lapdm_lb_vals[] = {
-+    { 0,		"More blocks" },
-+    { 1,		"Last block" },
-+    { 0,		NULL }
++static const value_string smscb_addr_lb_vals[] = {
++	{ 0,		"More blocks" },
++	{ 1,		"Last block" },
++	{ 0,		NULL }
 +};
 +
 +/* 04.12 section 3.3.1 */
-+static const value_string lapdm_seq_vals[] = {
-+    { 0,		"First block" },
-+    { 1,		"Second block" },
-+    { 2,		"Third block" },
-+    { 3,		"Fourth block" },
-+    { 8,		"First schedule block" },
-+    { 15,		"Null message" },
-+    { 0,		NULL }
++static const value_string smscb_addr_seq_vals[] = {
++	{ 0,		"First block" },
++	{ 1,		"Second block" },
++	{ 2,		"Third block" },
++	{ 3,		"Fourth block" },
++	{ 8,		"First schedule block" },
++	{ 15,		"Null message" },
++	{ 0,		NULL }
 +};
 +
 +/* 03.41 section 9.3.2.1 */
-+static const value_string lapdm_serial_gs_vals[] = {
-+    { 0,		"Cell wide (immediate)" },
-+    { 1,		"PLMN wide" },
-+    { 2,		"Location Area wide" },
-+    { 3,		"Cell wide" },
-+    { 0,		NULL }
++static const value_string smscb_serial_gs_vals[] = {
++	{ 0,		"Cell wide (immediate)" },
++	{ 1,		"PLMN wide" },
++	{ 2,		"Location Area wide" },
++	{ 3,		"Cell wide" },
++	{ 0,		NULL }
 +};
 +
- 
- static const fragment_items lapdm_frag_items = {
-     /* Fragment subtrees */
-@@ -209,6 +258,79 @@ lapdm_defragment_init (void)
- 
- 
- static void
-+dissect_lapdm_cb(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
++
++static const fragment_items smscb_frag_items = {
++	/* Fragment subtrees */
++	&ett_smscb_fragment,
++	&ett_smscb_fragments,
++	/* Fragment fields */
++	&hf_smscb_fragments,
++	&hf_smscb_fragment,
++	&hf_smscb_fragment_overlap,
++	&hf_smscb_fragment_overlap_conflicts,
++	&hf_smscb_fragment_multiple_tails,
++	&hf_smscb_fragment_too_long_fragment,
++	&hf_smscb_fragment_error,
++	/* Reassembled in field */
++	&hf_smscb_reassembled_in,
++	/* Reassembled length field */
++	&hf_smscb_reassembled_length,
++	/* Tag */
++	"fragments"
++};
++
++static void smscb_defragment_init(void)
 +{
-+    proto_tree *lapdm_tree, *addr_tree;
-+    proto_item *lapdm_ti, *addr_ti;
-+    guint8 addr, seq;
-+    tvbuff_t *payload;
-+    int offset;
-+    int length, out_len;
-+    gchar msgbuf[88];
-+
-+    addr = tvb_get_guint8(tvb, 0);
-+    if (tree) {
-+        lapdm_ti = proto_tree_add_item(tree, proto_lapdm, tvb, 0, LAPDM_CB_HEADER_LEN, FALSE);
-+        lapdm_tree = proto_item_add_subtree(lapdm_ti, ett_lapdm);
-+
-+        addr_ti = proto_tree_add_uint(lapdm_tree, hf_lapdm_address, tvb, 0, 1, addr);
-+        addr_tree = proto_item_add_subtree(addr_ti, ett_lapdm_address);
-+
-+        proto_tree_add_uint(addr_tree, hf_lapdm_lpd, tvb, 0, 1, addr);
-+        proto_tree_add_uint(addr_tree, hf_lapdm_cb_lb, tvb, 0, 1, addr);
-+        proto_tree_add_uint(addr_tree, hf_lapdm_cb_seq, tvb, 0, 1, addr);
-+    } else {
-+        lapdm_ti = NULL;
-+        lapdm_tree = NULL;
-+    }
++	fragment_table_init(&smscb_fragment_table);
++	reassembled_table_init(&smscb_reassembled_table);
++}
 +
-+    col_append_str(pinfo->cinfo, COL_INFO, "CBS ");
++/* [3GPP TS 03.41 section 9.3] */
++static int dissect_smscb_message(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
++{
++	proto_item *ti;
++	gint offset = 0;
++	gint length, out_len, textlen;
++	guint8 encoding;
++	gchar msgbuf[88 + 1];
++	gchar *utf8_text, *p;
 +
-+    offset = 1;
++	proto_tree_add_item(tree, hf_smscb_serial_gs, tvb, offset, 1, ENC_NA);
++	proto_tree_add_item(tree, hf_smscb_serial_mcode, tvb, offset, 2, ENC_NA);
++	offset++;
++	proto_tree_add_item(tree, hf_smscb_serial_updnum, tvb, offset, 1, ENC_NA);
++	offset++;
++	proto_tree_add_item(tree, hf_smscb_msgid, tvb, offset, 1, ENC_BIG_ENDIAN);
++	offset += 2;
++	ti = proto_tree_add_text(tree, tvb, offset, 1, "Data Coding Scheme");
++	encoding = dissect_cbs_data_coding_scheme(
++		tvb_new_subset(tvb, offset, 1, -1), pinfo,
++		proto_item_add_subtree(ti, ett_smscb_dcs));
++	offset++;
++	proto_tree_add_item(tree, hf_smscb_page_num, tvb, offset, 1, ENC_NA);
++	proto_tree_add_item(tree, hf_smscb_page_cnt, tvb, offset, 1, ENC_NA);
++	offset++;
 +
-+    /* TODO: reassemble blocks 1-3 */
-+    seq = addr & LAPDM_CB_SEQ;
-+    if (seq == 0) {
-+        proto_item *ti;
-+        proto_tree *subtree;
++	length = tvb_length(tvb) - offset;
++	switch (encoding) {
++	case SMS_ENCODING_7BIT:
++	case SMS_ENCODING_7BIT_LANG:
++		out_len = gsm_sms_char_7bit_unpack(0, length, sizeof(msgbuf) - 1,
++				tvb_get_ptr(tvb, offset, length), msgbuf);
++		msgbuf[out_len] = '\0';
++		utf8_text = gsm_sms_chars_to_utf8(msgbuf, out_len);
++		textlen = strlen(utf8_text);
++		break;
++	/* TODO: UCS2? */
++	case SMS_ENCODING_8BIT:
++	default:
++		utf8_text = tvb_get_ephemeral_string(tvb, offset, length);
++		textlen = length;
++		break;
++	}
 +
-+        ti = proto_tree_add_text(lapdm_tree, tvb, offset, 2, "Serial Number");
-+        subtree = proto_item_add_subtree(ti, ett_lapdm_cbs_serial);
++	proto_tree_add_string(tree, hf_smscb_content, tvb, offset, length, utf8_text);
 +
-+        proto_tree_add_item(subtree, hf_lapdm_cbs_serial_gs, tvb, offset, 1, FALSE);
-+        proto_tree_add_item(subtree, hf_lapdm_cbs_serial_mcode, tvb, offset, 2, FALSE);
-+        offset++;
-+        proto_tree_add_item(subtree, hf_lapdm_cbs_serial_updnum, tvb, offset, 1, FALSE);
-+        offset++;
++	/* strip padding */
++	if ((p = strchr( utf8_text, '\r')))
++		*p = 0;
++	col_append_fstr(pinfo->cinfo, COL_INFO, " \"%s\"", utf8_text);
 +
-+        proto_tree_add_item(lapdm_tree, hf_lapdm_cbs_msgid, tvb, offset, 2, FALSE);
-+        offset += 2;
++	return tvb_length(tvb);
++}
 +
-+        ti = proto_tree_add_text(lapdm_tree, tvb, offset, 1, "Data Coding Scheme");
-+        subtree = proto_item_add_subtree(ti, ett_lapdm_cbs_dcs);
-+        dissect_cbs_data_coding_scheme(tvb_new_subset(tvb, offset, 1, -1), pinfo, subtree);
-+        offset++;
++static int dissect_gsm_smscb(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
++{
++	proto_item *ti;
++	proto_tree *gsm_smscb_tree = NULL;
++	proto_tree *subtree = NULL;
++	guint8 addr, seq, more;
++	tvbuff_t *payload;
 +
-+        proto_tree_add_item(lapdm_tree, hf_lapdm_cbs_page_num, tvb, offset, 1, FALSE);
-+        proto_tree_add_item(lapdm_tree, hf_lapdm_cbs_page_cnt, tvb, offset, 1, FALSE);
-+        offset++;
++	if (tvb_length(tvb) < SMSCB_HDR_MINLEN)
++		return 0;
 +
-+        length = tvb_length(tvb) - offset;
-+        out_len = gsm_sms_char_7bit_unpack(0, length, sizeof(msgbuf) - 1,
-+            tvb_get_ptr(tvb, offset, length), msgbuf);
-+        msgbuf[out_len] = '\0';
-+        proto_tree_add_string(lapdm_tree, hf_lapdm_cbs_content, tvb, offset, length,
-+            gsm_sms_chars_to_utf8(msgbuf, out_len));
++	addr = tvb_get_guint8(tvb, 0);
++	seq = addr & SMSCB_ADDR_SEQ;
++	more = !(addr & SMSCB_ADDR_LB) && seq < SMSCB_SEQ_LAST;
 +
-+        col_append_fstr(pinfo->cinfo, COL_INFO, " [%s]", gsm_sms_chars_to_utf8(msgbuf, out_len));
-+    }
++	col_set_str(pinfo->cinfo, COL_PROTOCOL, "SMSCB");
++
++	col_clear(pinfo->cinfo, COL_INFO);
++	col_append_fstr(pinfo->cinfo, COL_INFO, "seq=%d", seq);
++
++	if (tree) {
++		ti = proto_tree_add_item(tree, proto_gsm_smscb, tvb, 0, -1, ENC_NA);
++		gsm_smscb_tree = proto_item_add_subtree(ti, ett_smscb);
++
++		ti = proto_tree_add_item(gsm_smscb_tree, hf_smscb_addr, tvb, 0, 1, ENC_NA);
++		subtree = proto_item_add_subtree(ti, ett_smscb_addr);
++		proto_tree_add_item(subtree, hf_smscb_addr_lb, tvb, 0, 1, ENC_NA);
++		proto_tree_add_item(subtree, hf_smscb_addr_seq, tvb, 0, 1, ENC_NA);
++	}
 +
-+    payload = tvb_new_subset_remaining(tvb, offset);
-+    call_dissector(data_handle, payload, pinfo, tree);
++	payload = tvb_new_subset(tvb, 1, -1, -1);
++
++	if (reassemble_smscb && seq <= SMSCB_SEQ_LAST) {
++		fragment_data *frag;
++		guint32 frag_id = 0x42;
++		guchar expected_seq = 0;
++		tvbuff_t *reassembled = NULL;
++		gboolean save_fragmented = pinfo->fragmented;
++
++		frag = fragment_get(pinfo, frag_id, smscb_fragment_table);
++		if (frag) {
++			while (frag->next)
++				frag = frag->next;
++			expected_seq = frag->offset + 1;
++		}
++
++		/*
++		 * TS 03.41 section 8 says we should discard sequences
++		 * which do not consist of consecutive blocks
++		 */
++		if (seq != expected_seq)
++			g_free(fragment_delete(pinfo, frag_id, smscb_fragment_table));
++
++		pinfo->fragmented = more;
++		frag = fragment_add_seq_check(payload, 0, pinfo, frag_id,
++			smscb_fragment_table,
++			smscb_reassembled_table, seq,
++			tvb_length(payload),
++			more);
++
++		reassembled = process_reassembled_data(payload, 0, pinfo,
++			"Reassembled SMSCB", frag, &smscb_frag_items, NULL,
++			gsm_smscb_tree);
++
++		if (frag && pinfo->fd->num == frag->reassembled_in) {
++			dissect_smscb_message(reassembled, pinfo, gsm_smscb_tree);
++		} else {
++			col_append_str(pinfo->cinfo, COL_INFO, " (Fragment)");
++			proto_tree_add_text(gsm_smscb_tree, payload, 0, -1, "Fragment Data");
++		}
++
++		pinfo->fragmented = save_fragmented;
++	} else if (seq == 0) {
++		dissect_smscb_message(payload, pinfo, gsm_smscb_tree);
++	} else {
++		/* TODO: reassemble & dissect Schedule messages */
++		call_dissector(data_handle, payload, pinfo, tree);
++	}
++
++	return tvb_length(tvb);
 +}
 +
++static hf_register_info hf[] = {
++	{ &hf_smscb_addr, {
++		"Address Field", "smscb.addr", FT_UINT8, BASE_HEX,
++		NULL, 0x0,
++		"Address", HFILL,
++	}},
++	{ &hf_smscb_addr_lb, {
++		"LB", "smscb.addr.lb", FT_UINT8, BASE_DEC,
++		VALS(smscb_addr_lb_vals), SMSCB_ADDR_LB,
++		"Last Block bit", HFILL,
++	}},
++	{ &hf_smscb_addr_seq, {
++		"SEQ", "smscb.addr.seq", FT_UINT8, BASE_DEC,
++		VALS(smscb_addr_seq_vals), SMSCB_ADDR_SEQ,
++		"Sequence Number", HFILL,
++	}},
 +
-+static void
- dissect_lapdm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
- {
-     proto_tree *lapdm_tree, *addr_tree, *length_tree;
-@@ -227,6 +349,11 @@ dissect_lapdm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
-     col_set_str(pinfo->cinfo, COL_PROTOCOL, "LAPDm");
++	{ &hf_smscb_serial_gs, {
++		"Geographic Scope", "smscb.serial.gs", FT_UINT8, BASE_DEC,
++		VALS(smscb_serial_gs_vals), SMSCB_SERIAL_GS, NULL, HFILL,
++	}},
++	{ &hf_smscb_serial_mcode, {
++		"Message Code", "smscb.serial.mcode", FT_UINT16, BASE_DEC,
++		NULL, SMSCB_SERIAL_MCODE, NULL, HFILL,
++	}},
++	{ &hf_smscb_serial_updnum, {
++		"Update Number", "smscb.serial.updnum", FT_UINT8, BASE_DEC,
++		NULL, SMSCB_SERIAL_MCODE, NULL, HFILL,
++	}},
++
++	{ &hf_smscb_msgid, {
++		"Message Identifier", "smscb.msgid", FT_UINT16, BASE_DEC,
++		NULL, 0, NULL, HFILL,
++	}},
++
++	{ &hf_smscb_page_num, {
++		"Page number", "smscb.page.num", FT_UINT8, BASE_DEC,
++		NULL, SMSCB_PAGE_NUM, NULL, HFILL,
++	}},
++	{ &hf_smscb_page_cnt, {
++		"Total pages", "smscb.page.cnt", FT_UINT8, BASE_DEC,
++		NULL, SMSCB_PAGE_CNT, NULL, HFILL,
++	}},
++	{ &hf_smscb_content, {
++		"Content of Message", "smscb.content", FT_STRING, BASE_NONE,
++		NULL, 0x00, NULL, HFILL,
++	}},
++
++	/* Fragment reassembly */
++	{ &hf_smscb_fragments, {
++		"Message fragments", "smscb.fragments",
++		FT_NONE, BASE_NONE, NULL, 0x00,
++		"SMSCB Message fragments", HFILL,
++	}},
++	{ &hf_smscb_fragment, {
++		"Message fragment", "smscb.fragment",
++		FT_FRAMENUM, BASE_NONE, NULL, 0x00,
++		"SMSCB Message fragment", HFILL,
++	}},
++	{ &hf_smscb_fragment_overlap, {
++		"Message fragment overlap", "smscb.fragment.overlap",
++		FT_BOOLEAN, BASE_NONE, NULL, 0x0,
++		"SMSCB Message fragment overlaps with other fragment(s)", HFILL,
++	}},
++	{ &hf_smscb_fragment_overlap_conflicts, {
++		"Message fragment overlapping with conflicting data", "smscb.fragment.overlap.conflicts",
++		FT_BOOLEAN, BASE_NONE, NULL, 0x0,
++		"SMSCB Message fragment overlaps with conflicting data", HFILL,
++	}},
++	{ &hf_smscb_fragment_multiple_tails, {
++		"Message has multiple tail fragments", "smscb.fragment.multiple_tails",
++		FT_BOOLEAN, BASE_NONE, NULL, 0x0,
++		"SMSCB Message fragment has multiple tail fragments", HFILL,
++	}},
++	{ &hf_smscb_fragment_too_long_fragment, {
++		"Message fragment too long", "smscb.fragment.too_long_fragment",
++		FT_BOOLEAN, BASE_NONE, NULL, 0x0,
++		"SMSCB Message fragment data goes beyond the packet end", HFILL,
++	}},
++	{ &hf_smscb_fragment_error, {
++		"Message defragmentation error", "smscb.fragment.error",
++		FT_FRAMENUM, BASE_NONE, NULL, 0x00,
++		"SMSCB Message defragmentation error due to illegal fragments", HFILL,
++	}},
++	{ &hf_smscb_reassembled_in, {
++		"Reassembled in", "smscb.reassembled.in",
++		FT_FRAMENUM, BASE_NONE, NULL, 0x00,
++		"SMSCB Message has been reassembled in this packet.", HFILL,
++	}},
++	{ &hf_smscb_reassembled_length, {
++		"Reassembled SMSCB length", "smscb.reassembled.length",
++		FT_UINT32, BASE_DEC, NULL, 0x00,
++		"The total length of the reassembled payload", HFILL,
++	}},
++};
++
++static gint *ett[] = {
++	&ett_smscb,
++	&ett_smscb_addr,
++	&ett_smscb_dcs,
++	&ett_smscb_fragment,
++	&ett_smscb_fragments,
++};
++
++void proto_reg_handoff_gsm_smscb(void)
++{
++	data_handle = find_dissector("data");
++}
++
++void proto_register_gsm_smscb(void)
++{
++	proto_gsm_smscb = proto_register_protocol(
++		"Short Message Service Cell Broadcast",
++		"SMSCB", "gsm_smscb");
++
++	proto_register_field_array(proto_gsm_smscb, hf, array_length(hf));
++	proto_register_subtree_array(ett, array_length(ett));
++
++	new_register_dissector("gsm_smscb", dissect_gsm_smscb, proto_gsm_smscb);
++	register_init_routine(smscb_defragment_init);
++}
+diff --git a/epan/dissectors/packet-lapdm.c b/epan/dissectors/packet-lapdm.c
+index dbeac85..add859d 100644
+--- a/epan/dissectors/packet-lapdm.c
++++ b/epan/dissectors/packet-lapdm.c
+@@ -110,6 +110,7 @@ static GHashTable *lapdm_reassembled_table = NULL;
+ static dissector_table_t lapdm_sapi_dissector_table;
+ 
+ static dissector_handle_t data_handle;
++static dissector_handle_t smscb_handle;
+ 
+ static gboolean reassemble_lapdm = TRUE;
+ 
+@@ -121,6 +122,7 @@ static gboolean reassemble_lapdm = TRUE;
+ #define	LAPDM_CR		0x02	/* Command/Response bit */
+ #define	LAPDM_EA		0x01	/* First Address Extension bit */
+ #define	LAPDM_LPD		0x60	/* Link Protocol Discriminator */
++#define	LAPDM_LPD_CB		0x20	/* Cell Broadcast LPD */
  
+ /*
+  * Bits in the length field.
+@@ -219,6 +221,7 @@ dissect_lapdm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+     tvbuff_t *payload;
+     int available_length;
+     gboolean is_response = FALSE;
++    gboolean is_cbs = FALSE;
+ 
+     /* Check that there's enough data */
+     if (tvb_length(tvb) < LAPDM_HEADER_LEN)
+@@ -229,6 +232,7 @@ dissect_lapdm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
      addr = tvb_get_guint8(tvb, 0);
-+    if ((addr & LAPDM_LPD) == LAPDM_LPD_CB) {
-+        dissect_lapdm_cb(tvb, pinfo, tree);
-+        return;
-+    }
-+
      length = tvb_get_guint8(tvb, 2);
  
++    is_cbs = (addr & LAPDM_LPD) == LAPDM_LPD_CB;
      cr = addr & LAPDM_CR;
-@@ -360,6 +487,39 @@ proto_register_lapdm(void)
-         { "SAPI", "lapdm.sapi", FT_UINT8, BASE_DEC, VALS(lapdm_sapi_vals), LAPDM_SAPI,
-         "Service access point identifier", HFILL }},
+     if (pinfo->p2p_dir == P2P_DIR_RECV) {
+         is_response = cr ? FALSE : TRUE;
+@@ -245,15 +249,22 @@ dissect_lapdm(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+         addr_tree = proto_item_add_subtree(addr_ti, ett_lapdm_address);
  
-+        { &hf_lapdm_cb_lb,
-+        { "LB", "lapdm.cb.lb", FT_UINT8, BASE_DEC,
-+        VALS(lapdm_lb_vals), LAPDM_CB_LB, "Last Block bit", HFILL }},
-+
-+        { &hf_lapdm_cb_seq,
-+        { "SEQ", "lapdm.cb.seq", FT_UINT8, BASE_DEC,
-+        VALS(lapdm_seq_vals), LAPDM_CB_SEQ, "Sequence Number", HFILL }},
-+
-+        { &hf_lapdm_cbs_serial_gs,
-+        { "GS", "lapdm.cbs.serial.gs", FT_UINT8, BASE_DEC,
-+        VALS(lapdm_serial_gs_vals), LAPDM_CBS_SERIAL_GS, "Geographic Scope", HFILL }},
-+        { &hf_lapdm_cbs_serial_mcode,
-+        { "Message Code", "lapdm.cbs.serial.mcode", FT_UINT16, BASE_DEC,
-+        NULL, LAPDM_CBS_SERIAL_MCODE, NULL, HFILL }},
-+        { &hf_lapdm_cbs_serial_updnum,
-+        { "Update Number", "lapdm.cbs.serial.updnum", FT_UINT8, BASE_DEC,
-+        NULL, LAPDM_CBS_SERIAL_MCODE, NULL, HFILL }},
-+
-+        { &hf_lapdm_cbs_msgid,
-+        { "Message Identifier", "lapdm.cbs.msgid", FT_UINT16, BASE_DEC,
-+        NULL, 0, NULL, HFILL }},
-+
-+        { &hf_lapdm_cbs_page_num,
-+        { "Page number", "lapdm.cbs.page.num", FT_UINT8, BASE_DEC,
-+        NULL, 0xf0, NULL, HFILL }},
-+        { &hf_lapdm_cbs_page_cnt,
-+        { "Total pages", "lapdm.cbs.page.cnt", FT_UINT8, BASE_DEC,
-+        NULL, 0x0f, NULL, HFILL }},
-+
-+        { &hf_lapdm_cbs_content,
-+        { "Content of Message", "lapdm.cbs.content", FT_STRING, BASE_NONE,
-+        NULL, 0x00, NULL, HFILL }},
-+
-         { &hf_lapdm_control,
-         { "Control Field", "lapdm.control_field", FT_UINT8, BASE_HEX, NULL, 0x0,
-         NULL, HFILL }},
-@@ -461,7 +621,9 @@ proto_register_lapdm(void)
-         &ett_lapdm_control,
-         &ett_lapdm_length,
-         &ett_lapdm_fragment,
--        &ett_lapdm_fragments
-+        &ett_lapdm_fragments,
-+        &ett_lapdm_cbs_serial,
-+        &ett_lapdm_cbs_dcs,
-     };
+         proto_tree_add_uint(addr_tree, hf_lapdm_lpd, tvb, 0, 1, addr);
+-        proto_tree_add_uint(addr_tree, hf_lapdm_sapi, tvb, 0, 1, addr);
+-        proto_tree_add_uint(addr_tree, hf_lapdm_cr, tvb, 0, 1, addr);
+-        proto_tree_add_uint(addr_tree, hf_lapdm_ea, tvb, 0, 1, addr);
++        if (!is_cbs) {
++            proto_tree_add_uint(addr_tree, hf_lapdm_sapi, tvb, 0, 1, addr);
++            proto_tree_add_uint(addr_tree, hf_lapdm_cr, tvb, 0, 1, addr);
++            proto_tree_add_uint(addr_tree, hf_lapdm_ea, tvb, 0, 1, addr);
++        }
+     }
+     else {
+         lapdm_ti = NULL;
+         lapdm_tree = NULL;
+     }
+ 
++    if (is_cbs) {
++        call_dissector(smscb_handle, tvb, pinfo, tree);
++        return;
++    }
++
+     control = dissect_xdlc_control(tvb, 1, pinfo, lapdm_tree, hf_lapdm_control,
+               ett_lapdm_control, &lapdm_cf_items, NULL /* LAPDm doesnt support extended */, NULL, NULL,
+               is_response, FALSE, FALSE);
+@@ -486,5 +497,6 @@ void
+ proto_reg_handoff_lapdm(void)
+ {
+     data_handle = find_dissector("data");
++    smscb_handle = find_dissector("gsm_smscb");
+ }
  
-     module_t *lapdm_module;