NMT / SMS: Short Message Service support

6 files changed, 883 insertions, 9 deletions

diff --git a/src/nmt/Makefile.am b/src/nmt/Makefile.am
index dee1ccd..a93e45b 100644
--- a/src/nmt/Makefile.am
+++ b/src/nmt/Makefile.am
@@ -8,6 +8,7 @@ nmt_SOURCES = \
 	dsp.c \
 	frame.c \
 	dms.c \
+	sms.c \
 	image.c \
 	tones.c \
 	announcement.c \
diff --git a/src/nmt/main.c b/src/nmt/main.c
index 3e9356b..352545d 100644
--- a/src/nmt/main.c
+++ b/src/nmt/main.c
@@ -24,6 +24,10 @@
 #include <string.h>
 #include <signal.h>
 #include <sched.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
 #include "../common/main.h"
 #include "../common/debug.h"
 #include "../common/timer.h"
@@ -36,6 +40,9 @@
 #include "tones.h"
 #include "announcement.h"
 
+#define SMS_FIFO "/tmp/nmt_sms_deliver"
+static int sms_fd = -1;
+
 /* settings */
 int num_chan_type = 0;
 enum nmt_chan_type chan_type[MAX_SENDER] = { CHAN_TYPE_CC_TC };
@@ -44,6 +51,7 @@ char traffic_area[3] = "";
 char area_no = 0;
 int compandor = 1;
 int supervisory = 0;
+const char *smsc_number = "767";
 
 void print_help(const char *arg0)
 {
@@ -69,6 +77,9 @@ void print_help(const char *arg0)
 	printf(" -0 --supervisory 1..4 | 0\n");
 	printf("        Use supervisory signal 1..4 to detect loss of signal from mobile\n");
 	printf("        station, use 0 to disable. (default = '%d')\n", supervisory);
+	printf(" -S --smsc-number <digits>\n");
+	printf("        If this number is dialed, the mobile is connected to the SMSC (Short\n");
+	printf("        Message Service Center). (default = '%s')\n", smsc_number);
 	printf("\nstation-id: Give 7 digits of station-id, you don't need to enter it\n");
 	printf("        for every start of this program.\n");
 }
@@ -85,10 +96,11 @@ static int handle_options(int argc, char **argv)
 		{"traffic-area", 1, 0, 'y'},
 		{"compandor", 1, 0, 'C'},
 		{"supervisory", 1, 0, '0'},
+		{"smsc-number", 1, 0, 'S'},
 		{0, 0, 0, 0}
 	};
 
-	set_options_common("t:P:a:y:C:0:", long_options_special);
+	set_options_common("t:P:a:y:C:0:S:", long_options_special);
 
 	while (1) {
 		int option_index = 0, c, rc;
@@ -176,6 +188,10 @@ error_ta:
 			}
 			skip_args += 2;
 			break;
+		case 'S':
+			smsc_number = strdup(optarg);
+			skip_args += 2;
+			break;
 		default:
 			opt_switch_common(c, argv[0], &skip_args);
 		}
@@ -186,6 +202,33 @@ error_ta:
 	return skip_args;
 }
 
+static void myhandler(void)
+{
+	static char buffer[256];
+	static int pos = 0, rc, i;
+	int space = sizeof(buffer) - pos;
+
+	rc = read(sms_fd, buffer + pos, space);
+	if (rc > 0) {
+		pos += rc;
+		if (pos == space) {
+			fprintf(stderr, "SMS buffer overflow!\n");
+			pos = 0;
+		}
+		/* check for end of line */
+		for (i = 0; i < pos; i++) {
+			if (buffer[i] == '\r' || buffer[i] == '\n')
+				break;
+		}
+		/* send sms */
+		if (i < pos) {
+			buffer[i] = '\0';
+			pos = 0;
+			deliver_sms(buffer);
+		}
+	}
+}
+
 int main(int argc, char *argv[])
 {
 	int rc;
@@ -237,6 +280,20 @@ int main(int argc, char *argv[])
 		return 0;
 	}
 
+	/* create pipe for SMS delivery */
+	unlink(SMS_FIFO);
+	rc = mkfifo(SMS_FIFO, 0666);
+	if (rc < 0) {
+		fprintf(stderr, "Failed to create SMS deliver FIFO!\n");
+		goto fail;
+	} else {
+		sms_fd = open(SMS_FIFO, O_RDONLY | O_NONBLOCK);
+		if (sms_fd < 0) {
+			fprintf(stderr, "Failed to open SMS deliver FIFO!\n");
+			goto fail;
+		}
+	}
+
 	if (!loopback)
 		print_image();
 
@@ -258,7 +315,7 @@ int main(int argc, char *argv[])
 
 	/* create transceiver instance */
 	for (i = 0; i < num_kanal; i++) {
-		rc = nmt_create(kanal[i], (loopback) ? CHAN_TYPE_TEST : chan_type[i], sounddev[i], samplerate, cross_channels, rx_gain, do_pre_emphasis, do_de_emphasis, write_wave, read_wave, ms_power, nmt_digits2value(traffic_area, 2), area_no, compandor, supervisory, loopback);
+		rc = nmt_create(kanal[i], (loopback) ? CHAN_TYPE_TEST : chan_type[i], sounddev[i], samplerate, cross_channels, rx_gain, do_pre_emphasis, do_de_emphasis, write_wave, read_wave, ms_power, nmt_digits2value(traffic_area, 2), area_no, compandor, supervisory, smsc_number, loopback);
 		if (rc < 0) {
 			fprintf(stderr, "Failed to create transceiver instance. Quitting!\n");
 			goto fail;
@@ -286,7 +343,7 @@ int main(int argc, char *argv[])
 			fprintf(stderr, "Error setting SCHED_RR with prio %d\n", rt_prio);
 	}
 
-	main_loop(&quit, latency, interval, NULL);
+	main_loop(&quit, latency, interval, myhandler);
 
 	if (rt_prio > 0) {
 		struct sched_param schedp;
@@ -297,6 +354,11 @@ int main(int argc, char *argv[])
 	}
 
 fail:
+	/* fifo */
+	if (sms_fd > 0)
+		close(sms_fd);
+	unlink(SMS_FIFO);
+
 	/* cleanup functions */
 	call_cleanup();
 	if (use_mncc_sock)
diff --git a/src/nmt/nmt.c b/src/nmt/nmt.c
index dbd5ff8..5c07e81 100644
--- a/src/nmt/nmt.c
+++ b/src/nmt/nmt.c
@@ -22,6 +22,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <errno.h>
+#include <time.h>
 #include "../common/debug.h"
 #include "../common/timer.h"
 #include "../common/call.h"
@@ -30,6 +31,8 @@
 #include "dsp.h"
 #include "frame.h"
 
+static int sms_ref = 0;
+
 /* Call reference for calls from mobile station to network
    This offset of 0x400000000 is required for MNCC interface. */
 static int new_callref = 0x40000000;
@@ -283,7 +286,7 @@ static void nmt_timeout(struct timer *timer);
 static void nmt_go_idle(nmt_t *nmt);
 
 /* Create transceiver instance and link to a list. */
-int nmt_create(int channel, enum nmt_chan_type chan_type, const char *sounddev, int samplerate, int cross_channels, double rx_gain, int pre_emphasis, int de_emphasis, const char *write_wave, const char *read_wave, uint8_t ms_power, uint8_t traffic_area, uint8_t area_no, int compandor, int supervisory, int loopback)
+int nmt_create(int channel, enum nmt_chan_type chan_type, const char *sounddev, int samplerate, int cross_channels, double rx_gain, int pre_emphasis, int de_emphasis, const char *write_wave, const char *read_wave, uint8_t ms_power, uint8_t traffic_area, uint8_t area_no, int compandor, int supervisory, const char *smsc_number, int loopback)
 {
 	nmt_t *nmt;
 	int rc;
@@ -337,13 +340,20 @@ int nmt_create(int channel, enum nmt_chan_type chan_type, const char *sounddev,
 		goto error;
 	}
 
-	/* init audio processing */
+	/* init DMS processing */
 	rc = dms_init_sender(nmt);
 	if (rc < 0) {
 		PDEBUG(DNMT, DEBUG_ERROR, "Failed to init DMS processing!\n");
 		goto error;
 	}
 
+	/* init SMS processing */
+	rc = sms_init_sender(nmt);
+	if (rc < 0) {
+		PDEBUG(DNMT, DEBUG_ERROR, "Failed to init SMS processing!\n");
+		goto error;
+	}
+
 	timer_init(&nmt->timer, nmt_timeout, nmt);
 	nmt->sysinfo.chan_type = chan_type;
 	nmt->sysinfo.ms_power = ms_power;
@@ -351,6 +361,7 @@ int nmt_create(int channel, enum nmt_chan_type chan_type, const char *sounddev,
 	nmt->sysinfo.area_no = area_no;
 	nmt->compandor = compandor;
 	nmt->supervisory = supervisory;
+	strncpy(nmt->smsc_number, smsc_number, sizeof(nmt->smsc_number) - 1);
 
 	/* go into idle state */
 	nmt_go_idle(nmt);
@@ -371,6 +382,7 @@ void nmt_destroy(sender_t *sender)
 	PDEBUG(DNMT, DEBUG_DEBUG, "Destroying 'NMT' instance for channel = %d.\n", sender->kanal);
 	dsp_cleanup_sender(nmt);
 	dms_cleanup_sender(nmt);
+	sms_cleanup_sender(nmt);
 	timer_exit(&nmt->timer);
 	sender_destroy(&nmt->sender);
 	free(nmt);
@@ -382,6 +394,8 @@ static void nmt_go_idle(nmt_t *nmt)
 	timer_stop(&nmt->timer);
 	nmt->page_for_nmt = NULL;
 	nmt->dms_call = 0;
+	dms_reset(nmt);
+	sms_reset(nmt);
 
 	PDEBUG(DNMT, DEBUG_INFO, "Entering IDLE state, sending idle frames on %s.\n", chan_type_long_name(nmt->sysinfo.chan_type));
 	nmt_new_state(nmt, STATE_IDLE);
@@ -760,9 +774,9 @@ static void rx_mo_dialing(nmt_t *nmt, frame_t *frame)
 			break;
 		PDEBUG(DNMT, DEBUG_INFO, "Dialing complete %s->%s, call established.\n", &nmt->subscriber.country, nmt->dialing);
 		/* setup call */
-		if (!strcmp(nmt->dialing, "767")) {
+		if (!strcmp(nmt->dialing, nmt->smsc_number)) {
 			/* SMS */
-			dms_reset(nmt);
+			PDEBUG(DNMT, DEBUG_INFO, "Setup call to SMSC.\n");
 			nmt->dms_call = 1;
 		} else {
 			int callref = ++new_callref;
@@ -980,6 +994,10 @@ static void tx_mt_complete(nmt_t *nmt, frame_t *frame)
 			super_reset(nmt);
 			timer_start(&nmt->timer, SUPERVISORY_TO1);
 		}
+		if (nmt->dms_call) {
+			time_t ti = time(NULL);
+			sms_deliver(nmt, sms_ref, "", SMS_TYPE_UKNOWN, SMS_PLAN_ISDN_TEL, ti, nmt->sms_string);
+		}
 	}
 }
 
@@ -1365,7 +1383,7 @@ const char *nmt_get_frame(nmt_t *nmt)
  */
 
 /* Call control starts call towards mobile station. */
-int call_out_setup(int callref, char *dialing)
+int _out_setup(int callref, char *dialing, const char *sms)
 {
 	sender_t *sender;
 	nmt_t *nmt;
@@ -1413,10 +1431,22 @@ inval:
 
 	/* 4. trying to page mobile station */
 	sender->callref = callref;
+	if (sms) {
+		strncpy(nmt->sms_string, sms, sizeof(nmt->sms_string) - 1);
+		nmt->dms_call = 1;
+	}
 	nmt_page(nmt, ms_country, ms_number, 1);
 
 	return 0;
 }
+int call_out_setup(int callref, char *dialing)
+{
+	return _out_setup(callref, dialing, NULL);
+}
+int sms_out_setup(char *dialing, const char *sms)
+{
+	return _out_setup(0, dialing, sms);
+}
 
 /* Call control sends disconnect (with tones).
  * An active call stays active, so tones and annoucements can be received
@@ -1519,3 +1549,61 @@ void call_rx_audio(int callref, int16_t *samples, int count)
 	}
 }
 
+/*
+ * SMS layer messages
+ */
+
+/* SMS layer releases */
+void sms_release(nmt_t *nmt)
+{
+	PDEBUG(DNMT, DEBUG_NOTICE, "Outgoing release, by SMS layer!\n");
+ 	nmt_release(nmt);
+}
+
+void sms_submit(nmt_t *nmt, uint8_t ref, const char *orig_address, uint8_t orig_type, uint8_t orig_plan, int msg_ref, const char *dest_address, uint8_t dest_type, uint8_t dest_plan, const char *message)
+{
+	PDEBUG(DNMT, DEBUG_NOTICE, "Received SMS from '%s' to '%s'\n", orig_address, dest_address);
+	printf("SMS received '%s' -> '%s': %s\n", orig_address, dest_address, message);
+
+}
+
+void sms_deliver_report(nmt_t *nmt, uint8_t ref, int error, uint8_t cause)
+{
+	PDEBUG(DNMT, DEBUG_NOTICE, "Got SMS deliver report\n");
+	if (error)
+		printf("SMS failed! (cause=%d)\n", cause);
+	else {
+		sms_ref++;
+		printf("SMS sent!\n");
+	}
+}
+
+/* application sends ud a message, we need to deliver */
+void deliver_sms(const char *sms)
+{
+	int i, rc;
+	char number[8];
+
+	/* check for number digits */
+	for (i = 0; i < 7; i++) {
+		if (sms[i] < '0' || sms[i] > '9')
+			break;
+	}
+	if (i < 7 || sms[7] != ',') {
+		PDEBUG(DNMT, DEBUG_NOTICE, "Given SMS MUST start with the 7 digits phone number, followed by a comma (no spaces)\n");
+		return;
+	}
+	strncpy(number, sms, 7);
+	number[7] = '\0';
+	sms += 8;
+	PDEBUG(DNMT, DEBUG_INFO, "SMS for subscriber '%s'\n", number);
+	printf("SMS sending SMSC -> '%s': %s\n", number, sms);
+
+	rc = sms_out_setup(number, sms);
+	if (rc < 0) {
+		PDEBUG(DNMT, DEBUG_INFO, "SMS delivery failed with cause '%d'\n", -rc);
+		return;
+	}
+}
+
+
diff --git a/src/nmt/nmt.h b/src/nmt/nmt.h
index 7a8c1d7..2ef1ba8 100644
--- a/src/nmt/nmt.h
+++ b/src/nmt/nmt.h
@@ -2,6 +2,7 @@
 #include "../common/compandor.h"
 #include "../common/dtmf.h"
 #include "dms.h"
+#include "sms.h"
 
 enum dsp_mode {
 	DSP_MODE_DIALTONE,	/* stream dial tone to mobile phone */
@@ -134,6 +135,12 @@ typedef struct nmt {
 	/* DMS states */
 	int			dms_call;		/* indicates that this call is a DMS call */
 	dms_t			dms;			/* DMS states */
+
+	/* SMS states */
+	char			smsc_number[33];	/* digits to match SMSC */
+	sms_t			sms;			/* SMS states */
+	struct timer		sms_timer;
+	char			sms_string[256];	/* current string to deliver */
 } nmt_t;
 
 void nmt_channel_list(void);
@@ -143,9 +150,10 @@ const char *chan_type_long_name(enum nmt_chan_type chan_type);
 double nmt_channel2freq(int channel, int uplink);
 void nmt_country_list(void);
 uint8_t nmt_country_by_short_name(const char *short_name);
-int nmt_create(int channel, enum nmt_chan_type chan_type, const char *sounddev, int samplerate, int cross_channels, double rx_gain, int pre_emphasis, int de_emphasis, const char *write_wave, const char *read_wave, uint8_t ms_power, uint8_t traffic_area, uint8_t area_no, int compandor, int supervisory, int loopback);
+int nmt_create(int channel, enum nmt_chan_type chan_type, const char *sounddev, int samplerate, int cross_channels, double rx_gain, int pre_emphasis, int de_emphasis, const char *write_wave, const char *read_wave, uint8_t ms_power, uint8_t traffic_area, uint8_t area_no, int compandor, int supervisory, const char *smsc_number, int loopback);
 void nmt_destroy(sender_t *sender);
 void nmt_receive_frame(nmt_t *nmt, const char *bits, double quality, double level, double frames_elapsed);
 const char *nmt_get_frame(nmt_t *nmt);
 void nmt_rx_super(nmt_t *nmt, int tone, double quality);
+void deliver_sms(const char *sms);
 
diff --git a/src/nmt/sms.c b/src/nmt/sms.c
new file mode 100644
index 0000000..484b68e
--- /dev/null
+++ b/src/nmt/sms.c
@@ -0,0 +1,681 @@
+/* NMT SMS (short message service) processing
+ *
+ * (C) 2016 by Andreas Eversberg <jolly@eversberg.eu>
+ * All Rights Reserved
+ *
+ * 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 3 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <errno.h>
+#include "../common/debug.h"
+#include "../common/timer.h"
+#include "nmt.h"
+
+#define SMS_RELEASE_TO		2.0
+
+/* TP-Message-Type-Indicator (TP-MTI) */
+#define	MTI_SMS_DELIVER		0x00 /* SC -> MS */
+#define	MTI_SMS_DELIVER_REPORT	0x00 /* MS -> SC */
+#define	MTI_SMS_STATUS_REPORT	0x02 /* SC -> MS */
+#define	MTI_SMS_COMMAND		0x02 /* MS -> SC */
+#define	MTI_SMS_SUBMIT		0x01 /* MS -> SC */
+#define	MTI_SMS_SUBMIT_REPORT	0x01 /* SC -> MS */
+#define MTI_MASK		0x03 /* Bits 0 and 1 */
+
+/* TP-More-Messages-to-Send (TP-MMS) */
+#define MMS_NORE		0x00
+#define MMS_NO_MORE		0x04
+#define MMS_MASK		0x04 /* Bit 2 */	
+
+/* TP-Validity-Period-Format (TP-VPF) */
+#define VPF_NOT_PRESENT		0x00
+#define VPF_PRESENT_INTEGER	0x10
+#define VPF_PRESENT_SEMI_OCTET	0x18
+#define VPF_MASK		0x18 /* Bits 3 and 4 */
+
+/* TP-Status-Report-Indication (TP-SRI) */
+#define SRI_NO_REPORT		0x00
+#define SRI_REPORT		0x20
+#define SRI_MASK		0x20
+
+/* TP-Status-Report-Request (TP-SRR) */
+#define SSR_NO_REPORT		0x00
+#define SSR_REPORT		0x20
+#define SSR_MASK		0x20
+
+/* TP-Failure-Cause (TP-FCS) */
+#define FCS_BUSY		0xc0
+#define FCS_NO_SC_SUBSCRIPTION	0xc1
+#define FSC_SC_SYSTEM_FAILURE	0xC2
+#define FSC_DEST_SME_BARRED	0xC4
+#define FSC_ERROR_IN_MS		0xD2
+#define FSC_MEMORY_EXCEEDED	0xD3
+#define FSC_UNSPECIFIED_ERROR	0xFF
+
+/* RP-Message-Type-Indicator (RP-MTI) */
+#define RP_MO_DATA		0x00	/* MS -> SC */
+#define RP_MT_DATA		0x01	/* SC -> MS */
+#define RP_MT_ACK		0x02	/* MS -> SC */
+#define RP_MO_ACK		0x03	/* SC -> MS */
+#define RP_MT_ERROR		0x04	/* MS -> SC */
+#define RP_MO_ERROR		0x05	/* SC -> MS */
+#define RP_SM_MEMORY_AVAILABLE	0x06	/* MS -> SC */
+#define RP_SM_READY_TO_RECEIVE	0x07	/* MS -> SC */
+#define RP_SM_NO_MESSAGE	0x07	/* SC -> MS */
+#define RP_MTI_MASK		0x07
+
+/* RP IEs */
+#define RP_IE_USER_DATA		0x41 /* wrong in NMT Doc.450-3 1998-04-03 */
+#define RP_IE_CAUSE		0x42
+
+/* SC -> MS header */
+static const char sms_header[] = {
+	0x01, 0x18, 0x53, 0x4d, 0x53, 0x48, 0x18, 'A', 'B', 'C', 0x02
+};
+
+/*
+ * init and exit
+ */
+
+static void sms_timeout(struct timer *timer);
+
+/* init instance */
+int sms_init_sender(nmt_t *nmt)
+{
+	timer_init(&nmt->sms_timer, sms_timeout, nmt);
+
+	return 0;
+}
+
+/* Cleanup transceiver instance. */
+void sms_cleanup_sender(nmt_t *nmt)
+{
+	timer_exit(&nmt->sms_timer);
+	sms_reset(nmt);
+}
+
+/*
+ * send to lower layer
+ */
+
+/* encode header */
+static int encode_header(uint8_t *data)
+{
+	memcpy(data, sms_header, sizeof(sms_header));
+
+	return sizeof(sms_header);
+}
+
+/* encode address fields */
+static int encode_address(uint8_t *data, const char *address, uint8_t type, uint8_t plan)
+{
+	int length = 1;
+	uint8_t digit;
+	int i, j;
+
+	PDEBUG(DSMS, DEBUG_DEBUG, "Encode SC->MS header\n");
+
+	data[length++] = 0x80 | (type << 4) | plan;
+	j = 0;
+	for (i = 0; address[i]; i++) {
+		if (address[i] >= '1' && address[i] <= '9')
+			digit = address[i] - '0';
+		else if (address[i] == '0')
+			digit = 10;
+		else if (address[i] == '*')
+			digit = 11;
+		else if (address[i] == '#')
+			digit = 12;
+		else if (address[i] == '+')
+			digit = 13;
+		else
+			continue;
+		if ((j & 1) == 0)
+			data[length] = digit;
+		else
+			data[length++] |= digit << 4;
+		j++;
+	}
+	if ((j & 1))
+		data[length++] |= 0xf0;
+
+	/* length field: number of semi-octets */
+	data[0] = j;
+
+	return length;
+}
+
+/* encode time stamp */
+static int encode_time(uint8_t *data, time_t timestamp)
+{
+	struct tm *tm = localtime(&timestamp);
+	int length = 0;
+	uint8_t digit1, digit2;
+	int quarters, sign;
+
+	PDEBUG(DSMS, DEBUG_DEBUG, "Encode time stamp '%02d.%02d.%02d %02d:%02d:%02d'\n", tm->tm_mday, tm->tm_mon + 1, tm->tm_year % 100, tm->tm_hour, tm->tm_min, tm->tm_sec);
+
+	/* year */
+	digit1 = (tm->tm_year % 100) / 10;
+	if (digit1 == 0)
+		digit1 = 10;
+	digit2 = tm->tm_year % 10;
+	if (digit2 == 0)
+		digit2 = 10;
+	data[length++] = (digit2 << 4) | digit1;
+
+	/* month */
+	digit1 = (tm->tm_mon + 1) / 10;
+	if (digit1 == 0)
+		digit1 = 10;
+	digit2 = (tm->tm_mon + 1) % 10;
+	if (digit2 == 0)
+		digit2 = 10;
+	data[length++] = (digit2 << 4) | digit1;
+
+	/* day */
+	digit1 = tm->tm_mday / 10;
+	if (digit1 == 0)
+		digit1 = 10;
+	digit2 = tm->tm_mday % 10;
+	if (digit2 == 0)
+		digit2 = 10;
+	data[length++] = (digit2 << 4) | digit1;
+
+	/* hour */
+	digit1 = tm->tm_hour / 10;
+	if (digit1 == 0)
+		digit1 = 10;
+	digit2 = tm->tm_hour % 10;
+	if (digit2 == 0)
+		digit2 = 10;
+	data[length++] = (digit2 << 4) | digit1;
+
+	/* min */
+	digit1 = tm->tm_min / 10;
+	if (digit1 == 0)
+		digit1 = 10;
+	digit2 = tm->tm_min % 10;
+	if (digit2 == 0)
+		digit2 = 10;
+	data[length++] = (digit2 << 4) | digit1;
+
+	/* sec */
+	digit1 = tm->tm_sec / 10;
+	if (digit1 == 0)
+		digit1 = 10;
+	digit2 = tm->tm_sec % 10;
+	if (digit2 == 0)
+		digit2 = 10;
+	data[length++] = (digit2 << 4) | digit1;
+
+	/* zone */
+	quarters = timezone / 900;
+	if (quarters < 0) {
+		quarters = -quarters;
+		sign = 1;
+	} else {
+		quarters = -quarters;
+		sign = 0;
+	}
+	data[length++] = (quarters << 4) | (sign << 3) | (quarters >> 4);
+
+	return length;
+}
+
+/* encode user data */
+static int encode_userdata(uint8_t *data, const char *message)
+{
+	int length = 1;
+	char character;
+	int i, j, pos;
+
+	PDEBUG(DSMS, DEBUG_DEBUG, "Encode user data '%s'\n", message);
+
+	j = 0;
+	pos = 0;
+	for (i = 0; message[i]; i++) {
+		if (message[i] < 128)
+			character = message[i];
+		else
+			character = '?';
+		j++;
+		if (pos == 0) {
+			/* character fits and is aligned to the right, new octet */
+			data[length] = character;
+			pos = 7;
+		} else {
+			/* character is shifted by pos */
+			data[length] |= character << pos;
+			if (pos > 1) {
+				/* not all bits fit in octet, so fill the rest to next octet */
+				length++;
+				data[length] = character >> (8 - pos);
+				pos--;
+			} else {
+				/* all bits fit in octet, so go to next octet */
+				pos = 0;
+				length++;
+			}
+		}
+	}
+	if (pos)
+		length++;
+
+	/* length field: number of characters */
+	data[0] = j;
+
+	return length;
+}
+
+/* deliver SMS (SC->MS) */
+int sms_deliver(nmt_t *nmt, uint8_t ref, const char *orig_address, uint8_t orig_type, uint8_t orig_plan, time_t timestamp, const char *message)
+{
+	uint8_t data[256], *tpdu_length;
+	int length = 0;
+	int orig_len;
+	int msg_len;
+
+	PDEBUG(DSMS, DEBUG_DEBUG, "Delivering SMS from upper layer\n");
+
+	orig_len = strlen(orig_address);
+	msg_len = strlen(message);
+
+	if (orig_len > 24) {
+		PDEBUG(DSMS, DEBUG_NOTICE, "Originator Address too long (%d characters)\n", orig_len);
+		return -EINVAL;
+	}
+	if (msg_len > 140) {
+		PDEBUG(DSMS, DEBUG_NOTICE, "Message too long (%d characters)\n", msg_len);
+		return -EINVAL;
+	}
+
+	/* HEADER */
+	length = encode_header(data);
+
+	/* RP */
+	data[length++] = RP_MT_DATA;
+	data[length++] = ref;
+	data[length++] = RP_IE_USER_DATA;
+	tpdu_length = data + length++;
+
+	/* TP */
+	data[length++] = MTI_SMS_DELIVER | MMS_NO_MORE | VPF_NOT_PRESENT | SRI_NO_REPORT;
+	length += encode_address(data + length, orig_address, orig_type, orig_plan); /* TP-OA */
+	data[length++] = 0; /* TP-PID */
+	data[length++] = 0; /* TP-DCS */
+	length += encode_time(data + length, timestamp);
+	length += encode_userdata(data + length, message);
+
+	/* RP length */
+	*tpdu_length = length - (uint8_t)(tpdu_length - data) - 1;
+	PDEBUG(DSMS, DEBUG_DEBUG, " -> TPDU lenght = %d\n", *tpdu_length);
+
+	nmt->sms.mt = 1;
+	dms_send(nmt, data, length, 1);
+
+	return 0;
+}
+
+/* report SMS (SC->MS) */
+static void sms_submit_report(nmt_t *nmt, uint8_t ref, int error)
+{
+	uint8_t data[64];
+	int length = 0;
+
+	PDEBUG(DSMS, DEBUG_DEBUG, "Sending Submit Report (%s)\n", (error) ? "error" : "ok");
+
+	/* HEADER */
+	length = encode_header(data);
+
+	/* RP */
+	data[length++] = (error) ? RP_MO_ERROR : RP_MO_ACK;
+	data[length++] = ref;
+
+	dms_send(nmt, data, length, 1);
+}
+
+/*
+ * receive from lower layer
+ */
+
+/* decdoe message from 8 bit data */
+static void decode_message(const uint8_t *data, int length, char *message)
+{
+	int fill;
+	int i;
+	uint16_t result;
+
+	fill = 0;
+	result = 0;
+	for (i = 0; i < length; i++) {
+		result |= data[i] << fill;
+		fill += 8;
+		while (fill >= 7) {
+			*message++ = result & 0x7f;
+			result >>= 7;
+			fill -= 7;
+		}
+	}
+	*message++ = '\0';
+}
+
+static const char digits2ascii[16] = {
+	'?', '1', '2', '3', '4', '5', '6', '7',
+	'8', '9', '0', '*', '#', '+', '?', '?' };
+
+static void decode_address(const uint8_t *data, int digits, char *address)
+{
+	int i;
+
+	for (i = 0; i < digits; i++) {
+		if (!(i & 1))
+			*address++ = digits2ascii[(*data) & 0xf];
+		else
+			*address++ = digits2ascii[(*data++) >> 4];
+	}
+	*address++ = '\0';
+}
+
+/* decode sms submit message
+ * return 1 if done, -1 if failed, 0, if more data is required */
+static int decode_sms_submit(nmt_t *nmt, const uint8_t *data, int length)
+{
+	uint8_t ref, msg_ref;
+	const uint8_t *orig_data, *tpdu_data, *dest_data, *msg_data;
+	int orig_len, tpdu_len, dest_len, msg_len;
+	int orig_digits, dest_digits, msg_chars;
+	uint8_t orig_type, orig_plan, dest_type, dest_plan;
+	int tp_vpf_present = 0;
+
+	/* decode ref */
+	ref = data[1];
+	data += 2;
+	length -= 2;
+
+	/* do we have originator address length ? */
+	if (length < 2) {
+		PDEBUG(DSMS, DEBUG_DEBUG, "SMS still incomplete, waiting for originator address\n");
+		return 0;
+	}
+	orig_data = 2 + data;
+	orig_digits = data[0];
+	orig_type = (data[1] >> 4) & 0x7;
+	orig_plan = data[1] & 0x0f;
+	orig_len = (orig_digits + 1) >> 1;
+	if (length < 2 + orig_len) {
+		PDEBUG(DSMS, DEBUG_DEBUG, "SMS still incomplete, waiting for originator address digits (got %d of %d)\n", length - 1, orig_len);
+		return 0;
+	}
+	data += 2 + orig_len;
+	length -= 2 + orig_len;
+	
+	/* do we have user data IE ? */
+	if (length < 2) {
+		PDEBUG(DSMS, DEBUG_DEBUG, "SMS still incomplete, waiting for user data IE\n");
+		return 0;
+	}
+	if (data[0] != RP_IE_USER_DATA) {
+		PDEBUG(DSMS, DEBUG_NOTICE, "missing user data IE\n");
+		return -1;
+	}
+	tpdu_len = data[1];
+	tpdu_data = 2 + data;
+	if (length < 2 + tpdu_len) {
+		PDEBUG(DSMS, DEBUG_DEBUG, "SMS still incomplete, waiting for TPDU to be complete\n");
+		return 0;
+	}
+	data += 2 + tpdu_len;
+	length -= 2 + tpdu_len;
+
+	/* decode orig address */
+	char orig_address[orig_digits + 1];
+	decode_address(orig_data, orig_digits, orig_address);
+	PDEBUG(DSMS, DEBUG_DEBUG, "Decoded originating addess: '%s'\n", orig_address);
+
+	/* go into TP */
+	data = tpdu_data;
+	length = tpdu_len;
+
+	/* check msg_type */
+	if (length < 1) {
+		PDEBUG(DSMS, DEBUG_NOTICE, "short read user data IE\n");
+		return -1;
+	}
+	if ((data[0] & MTI_MASK) != MTI_SMS_SUBMIT) {
+		PDEBUG(DSMS, DEBUG_NOTICE, "especting SUBMIT MTI, but got 0x%02x\n", data[0]);
+		return -1;
+	}
+	if ((data[0] & VPF_MASK))
+		tp_vpf_present = 1;
+	data++;
+	length--;
+
+	/* decode msg ref */
+	if (length < 1) {
+		PDEBUG(DSMS, DEBUG_NOTICE, "short read user data IE\n");
+		return -1;
+	}
+	msg_ref = data[0];
+	data++;
+	length--;
+
+	/* decode dest address */
+	if (length < 2) {
+		PDEBUG(DSMS, DEBUG_NOTICE, "short read user data IE\n");
+		return -1;
+	}
+	dest_data = 2 + data;
+	dest_digits = data[0];
+	dest_type = (data[1] >> 4) & 0x7;
+	dest_plan = data[1] & 0x0f;
+	dest_len = (dest_digits + 1) >> 1;
+	if (length < 2 + dest_len) {
+		PDEBUG(DSMS, DEBUG_NOTICE, "short read user data IE\n");
+		return -1;
+	}
+	data += 2 + dest_len;
+	length -= 2 + dest_len;
+	char dest_address[dest_digits + 1];
+	decode_address(dest_data, dest_digits, dest_address);
+	PDEBUG(DSMS, DEBUG_DEBUG, "Decoded destination addess: '%s'\n", dest_address);
+
+	/* skip above protocol identifier */
+	if (length < 1) {
+		PDEBUG(DSMS, DEBUG_NOTICE, "short read above protocol identifier IE\n");
+		return -1;
+	}
+	data++;
+	length--;
+
+	/* decode data coding scheme */
+	if (length < 1) {
+		PDEBUG(DSMS, DEBUG_NOTICE, "short data coding scheme IE\n");
+		return -1;
+	}
+	if (data[0] != 0) {
+		PDEBUG(DSMS, DEBUG_NOTICE, "SMS coding unsupported (got 0x%02x)\n", data[0]);
+		return -1;
+	}
+	data++;
+	length--;
+
+	/* skip validity period */
+	if (tp_vpf_present) {
+		if (length < 1) {
+			PDEBUG(DSMS, DEBUG_NOTICE, "short read validity period IE\n");
+			return -1;
+		}
+		data++;
+		length--;
+	}
+
+	/* decode data message text */
+	if (length < 1) {
+		PDEBUG(DSMS, DEBUG_NOTICE, "short read user data IE\n");
+		return -1;
+	}
+	msg_data = data + 1;
+	msg_chars = data[0];
+	msg_len = (msg_chars * 7 + 7) / 8;
+	if (length < 1 + msg_len) {
+		PDEBUG(DSMS, DEBUG_NOTICE, "short read user data IE\n");
+		return -1;
+	}
+	char message[msg_chars + 1];
+	decode_message(msg_data, msg_len, message);
+	PDEBUG(DSMS, DEBUG_DEBUG, "Decoded message: '%s'\n", message);
+
+	sms_submit(nmt, ref, orig_address, orig_type, orig_plan, msg_ref, dest_address, dest_type, dest_plan, message);
+
+	return 1;
+}
+
+/* decode deliver report
+ * return 1 if done, -1 if failed, 0, if more data is required */
+static int decode_deliver_report(nmt_t *nmt, const uint8_t *data, int length)
+{
+	uint8_t ref, cause = 0;
+	int error = 0;
+
+	ref = data[1];
+
+	if ((data[0] & RP_MTI_MASK) == RP_MT_ERROR) {
+		error = 1;
+		if (length < 4) {
+			PDEBUG(DSMS, DEBUG_DEBUG, "deliver report still incomplete, waiting for cause IE\n");
+			return 0;
+		}
+		if (length < 4 + data[3]) {
+			PDEBUG(DSMS, DEBUG_DEBUG, "deliver report still incomplete, waiting for cause IE content\n");
+			return 0;
+		}
+		if (data[2] == RP_IE_CAUSE && data[3] > 0)
+			cause = data[4];
+		PDEBUG(DSMS, DEBUG_DEBUG, "Decoded delivery report: ERROR, cause=%d\n", cause);
+	} else
+		PDEBUG(DSMS, DEBUG_DEBUG, "Decoded delivery report: OK\n");
+
+	sms_deliver_report(nmt, ref, error, cause);
+
+	return 1;
+}
+
+/* receive from DMS layer */
+void dms_receive(nmt_t *nmt, const uint8_t *data, int length, int eight_bits)
+{
+	sms_t *sms = &nmt->sms;
+	int space;
+	int rc = 0;
+	char debug_text[length * 5 + 1];
+	int i;
+
+	for (i = 0; i < length; i++)
+		sprintf(debug_text + i * 5, " 0x%02x", data[i]);
+	debug_text[length * 5] = '\0';
+
+	PDEBUG(DSMS, DEBUG_DEBUG, "Received %d bytes from DMS layer:%s\n", length, debug_text);
+
+	if (sms->mt && !sms->data_sent) {
+		PDEBUG(DSMS, DEBUG_NOTICE, "Ignoring data while we transmit data\n");
+		return;
+	}
+
+	/* append received data */
+	space = sizeof(sms->rx_buffer) - sms->rx_count;
+	if (space < length) {
+		PDEBUG(DSMS, DEBUG_NOTICE, "Received message exceeds RX buffer, terminating call!\n");
+release:
+		timer_start(&nmt->sms_timer, SMS_RELEASE_TO);
+		return;
+	}
+	memcpy(sms->rx_buffer + sms->rx_count, data, length);
+	sms->rx_count += length;
+
+	/* go into buffer */
+	data = sms->rx_buffer;
+	length = sms->rx_count;
+
+	/* check if complete */
+	if (length < 2)
+		return;
+	switch (data[0] & RP_MTI_MASK) {
+	case RP_MT_ACK:
+		rc = decode_deliver_report(nmt, data, length);
+		break;
+	case RP_MT_ERROR:
+		rc = decode_deliver_report(nmt, data, length);
+		break;
+	case RP_MO_DATA:
+		rc = decode_sms_submit(nmt, data, length);
+		if (rc < 0)
+			sms_submit_report(nmt, data[1], FSC_UNSPECIFIED_ERROR);
+		else if (rc > 0) {
+			sms_submit_report(nmt, data[1], 0);
+		}
+		/* no release, we release afeter the report */
+		rc = 0;
+		break;
+	case RP_SM_READY_TO_RECEIVE:
+		PDEBUG(DSMS, DEBUG_NOTICE, "Received READY-TO-RECEVIE message.\n");
+		data += length;
+		length -= length;
+		break;
+	default:
+		PDEBUG(DSMS, DEBUG_NOTICE, "Received unknown RP message type %d.\n", data[0]);
+		rc = -1;
+	}
+	if (rc)
+		goto release;
+	
+	return;
+}
+
+static void sms_timeout(struct timer *timer)
+{
+	nmt_t *nmt = (nmt_t *)timer->priv;
+
+	sms_release(nmt);
+}
+
+/* all data has been sent to mobile */
+void dms_all_sent(nmt_t *nmt)
+{
+	sms_t *sms = &nmt->sms;
+
+	if (!sms->data_sent) {
+		if (!sms->mt) {
+			PDEBUG(DSMS, DEBUG_DEBUG, "Done sending submit report, releasing.\n");
+			timer_start(&nmt->sms_timer, SMS_RELEASE_TO);
+		}
+		sms->data_sent = 1;
+		PDEBUG(DSMS, DEBUG_DEBUG, "DMS layer indicates acknowledge of sent data\n");
+	}
+}
+
+void sms_reset(nmt_t *nmt)
+{
+	sms_t *sms = &nmt->sms;
+
+	PDEBUG(DSMS, DEBUG_DEBUG, "Resetting SMS states\n");
+	timer_stop(&nmt->sms_timer);
+
+	memset(sms, 0, sizeof(*sms));
+}
+
diff --git a/src/nmt/sms.h b/src/nmt/sms.h
new file mode 100644
index 0000000..f7fcc10
--- /dev/null
+++ b/src/nmt/sms.h
@@ -0,0 +1,34 @@
+
+#define SMS_TYPE_UKNOWN		0x0
+#define SMS_TYPE_INTERNATIONAL	0x1
+#define SMS_TYPE_NATIONAL	0x2
+#define SMS_TYPE_NETWORK	0x3
+#define SMS_TYPE_SUBSCRIBER	0x4
+#define SMS_TYPE_ALPHANUMERIC	0x5
+#define SMS_TYPE_ABBREVIATED	0x6
+#define SMS_TYPE_RESERVED	0x7
+
+#define SMS_PLAN_UNKOWN		0x0
+#define SMS_PLAN_ISDN_TEL	0x1
+#define SMS_PLAN_DATA		0x3
+#define SMS_PLAN_TELEX		0x4
+#define SMS_PLAN_NATIONAL	0x8
+#define SMS_PLAN_PRIVATE	0x9
+#define SMS_PLAN_ERMES		0xa
+#define SMS_PLAN_RESERVED	0xf
+
+typedef struct sms {
+	uint8_t			rx_buffer[1024];		/* data received from MS */
+	int			rx_count;			/* number of bytes in buffer */
+	int			data_sent;			/* all pending data have been sent and was acked */
+	int			mt;				/* mobile terminating SMS */
+} sms_t;
+
+int sms_init_sender(nmt_t *nmt);
+void sms_cleanup_sender(nmt_t *nmt);
+void sms_submit(nmt_t *nmt, uint8_t ref, const char *orig_address, uint8_t orig_type, uint8_t orig_plan, int msg_ref, const char *dest_address, uint8_t dest_type, uint8_t dest_plan, const char *message);
+void sms_deliver_report(nmt_t *nmt, uint8_t ref, int error, uint8_t cause);
+int sms_deliver(nmt_t *nmt, uint8_t ref, const char *orig_address, uint8_t type, uint8_t plan, time_t timestamp, const char *message);
+void sms_release(nmt_t *nmt);
+void sms_reset(nmt_t *nmt);
+