diff --git a/src/input/Makefile.am b/src/input/Makefile.am
new file mode 100644
index 0000000..8e9e336
--- /dev/null
+++ b/src/input/Makefile.am
@@ -0,0 +1,11 @@
+noinst_LTLIBRARIES = libosmoabis-input.la
+
+INCLUDES = $(all_includes) -I$(top_srcdir)/include -I$(top_builddir)
+AM_CFLAGS= -fPIC -Wall $(LIBOSMOCORE_CFLAGS) $(LIBOSMOGSM_CFLAGS) $(LIBOSMOVTY_CFLAGS) $(COVERAGE_CFLAGS)
+AM_LDFLAGS = $(LIBOSMOCORE_LIBS) $(LIBOSMOGSM_LIBS) $(COVERAGE_LDFLAGS)
+
+libosmoabis_input_la_SOURCES  = dahdi.c		\
+				hsl.c		\
+				ipaccess.c	\
+				lapd.c		\
+				misdn.c
diff --git a/src/input/dahdi.c b/src/input/dahdi.c
new file mode 100644
index 0000000..a431a3a
--- /dev/null
+++ b/src/input/dahdi.c
@@ -0,0 +1,495 @@
+/* OpenBSC Abis input driver for DAHDI */
+
+/* (C) 2008-2011 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org>
+ * (C) 2010 by Digium and Matthew Fredrickson <creslin@digium.com>
+ *
+ * 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 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.
+ *
+ */
+
+//#include "../../../bscconfig.h"
+
+#ifdef HAVE_DAHDI_USER_H
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <time.h>
+#include <sys/fcntl.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <arpa/inet.h>
+#include <dahdi/user.h>
+
+#include <osmocom/core/select.h>
+#include <osmocom/core/msgb.h>
+#include <openbsc/debug.h>
+#include <openbsc/gsm_data.h>
+#include <openbsc/abis_nm.h>
+#include <openbsc/abis_rsl.h>
+#include <openbsc/subchan_demux.h>
+#include <openbsc/e1_input.h>
+#include <openbsc/signal.h>
+#include <talloc.h>
+
+#include "lapd.h"
+
+#define TS1_ALLOC_SIZE	300
+
+/* Corresponds to dahdi/user.h, only PRI related events */
+static const struct value_string dahdi_evt_names[] = {
+	{ DAHDI_EVENT_NONE,		"NONE" },
+	{ DAHDI_EVENT_ALARM,		"ALARM" },
+	{ DAHDI_EVENT_NOALARM,		"NOALARM" },
+	{ DAHDI_EVENT_ABORT,		"HDLC ABORT" },
+	{ DAHDI_EVENT_OVERRUN,		"HDLC OVERRUN" },
+	{ DAHDI_EVENT_BADFCS,		"HDLC BAD FCS" },
+	{ DAHDI_EVENT_REMOVED,		"REMOVED" },
+	{ 0, NULL }
+};
+
+static void handle_dahdi_exception(struct e1inp_ts *ts)
+{
+	int rc, evt;
+	struct input_signal_data isd;
+
+	rc = ioctl(ts->driver.dahdi.fd.fd, DAHDI_GETEVENT, &evt);
+	if (rc < 0)
+		return;
+
+	LOGP(DMI, LOGL_NOTICE, "Line %u(%s) / TS %u DAHDI EVENT %s\n",
+		ts->line->num, ts->line->name, ts->num,
+		get_value_string(dahdi_evt_names, evt));
+
+	isd.line = ts->line;
+
+	switch (evt) {
+	case DAHDI_EVENT_ALARM:
+		/* we should notify the code that the line is gone */
+		osmo_signal_dispatch(SS_INPUT, S_INP_LINE_ALARM, &isd);
+		break;
+	case DAHDI_EVENT_NOALARM:
+		/* alarm has gone, we should re-start the SABM requests */
+		osmo_signal_dispatch(SS_INPUT, S_INP_LINE_NOALARM, &isd);
+		break;
+	}
+}
+
+static int handle_ts1_read(struct osmo_fd *bfd)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+	struct msgb *msg = msgb_alloc(TS1_ALLOC_SIZE, "DAHDI TS1");
+	lapd_mph_type prim;
+	unsigned int sapi, tei;
+	int ilen, ret;
+	uint8_t *idata;
+
+	if (!msg)
+		return -ENOMEM;
+
+	ret = read(bfd->fd, msg->data, TS1_ALLOC_SIZE - 16);
+	if (ret == -1)
+		handle_dahdi_exception(e1i_ts);
+	else if (ret < 0) {
+		perror("read ");
+	}
+	msgb_put(msg, ret - 2);
+	if (ret <= 3) {
+		perror("read ");
+	}
+
+	sapi = msg->data[0] >> 2;
+	tei = msg->data[1] >> 1;
+
+	DEBUGP(DMI, "<= len = %d, sapi(%d) tei(%d)", ret, sapi, tei);
+
+	idata = lapd_receive(e1i_ts->driver.dahdi.lapd, msg->data, msg->len, &ilen, &prim);
+	if (!idata && prim == 0)
+		return -EIO;
+
+	msgb_pull(msg, 2);
+
+	DEBUGP(DMI, "prim %08x\n", prim);
+
+	switch (prim) {
+	case 0:
+		break;
+	case LAPD_MPH_ACTIVATE_IND:
+		DEBUGP(DMI, "MPH_ACTIVATE_IND: sapi(%d) tei(%d)\n", sapi, tei);
+		ret = e1inp_event(e1i_ts, S_INP_TEI_UP, tei, sapi);
+		break;
+	case LAPD_MPH_DEACTIVATE_IND:
+		DEBUGP(DMI, "MPH_DEACTIVATE_IND: sapi(%d) tei(%d)\n", sapi, tei);
+		ret = e1inp_event(e1i_ts, S_INP_TEI_DN, tei, sapi);
+		break;
+	case LAPD_DL_DATA_IND:
+	case LAPD_DL_UNITDATA_IND:
+		if (prim == LAPD_DL_DATA_IND)
+			msg->l2h = msg->data + 2;
+		else
+			msg->l2h = msg->data + 1;
+		DEBUGP(DMI, "RX: %s\n", osmo_hexdump(msgb_l2(msg), ret));
+		ret = e1inp_rx_ts(e1i_ts, msg, tei, sapi);
+		break;
+	default:
+		printf("ERROR: unknown prim\n");
+		break;
+	}
+
+	DEBUGP(DMI, "Returned ok\n");
+	return ret;
+}
+
+static int ts_want_write(struct e1inp_ts *e1i_ts)
+{
+	/* We never include the DAHDI B-Channel FD into the
+	 * writeset, since it doesn't support poll() based
+	 * write flow control */
+	if (e1i_ts->type == E1INP_TS_TYPE_TRAU) {
+		fprintf(stderr, "Trying to write TRAU ts\n");
+		return 0;
+	}
+
+	e1i_ts->driver.dahdi.fd.when |= BSC_FD_WRITE;
+
+	return 0;
+}
+
+static void timeout_ts1_write(void *data)
+{
+	struct e1inp_ts *e1i_ts = (struct e1inp_ts *)data;
+
+	/* trigger write of ts1, due to tx delay timer */
+	ts_want_write(e1i_ts);
+}
+
+static void dahdi_write_msg(uint8_t *data, int len, void *cbdata)
+{
+	struct osmo_fd *bfd = cbdata;
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+	int ret;
+
+	ret = write(bfd->fd, data, len + 2);
+	if (ret == -1)
+		handle_dahdi_exception(e1i_ts);
+	else if (ret < 0)
+		LOGP(DMI, LOGL_NOTICE, "%s write failed %d\n", __func__, ret);
+}
+
+static int handle_ts1_write(struct osmo_fd *bfd)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+	struct e1inp_sign_link *sign_link;
+	struct msgb *msg;
+
+	bfd->when &= ~BSC_FD_WRITE;
+
+	/* get the next msg for this timeslot */
+	msg = e1inp_tx_ts(e1i_ts, &sign_link);
+	if (!msg) {
+		/* no message after tx delay timer */
+		return 0;
+	}
+
+	DEBUGP(DMI, "TX: %s\n", osmo_hexdump(msg->data, msg->len));
+	lapd_transmit(e1i_ts->driver.dahdi.lapd, sign_link->tei,
+		      sign_link->sapi, msg->data, msg->len);
+	msgb_free(msg);
+
+	/* set tx delay timer for next event */
+	e1i_ts->sign.tx_timer.cb = timeout_ts1_write;
+	e1i_ts->sign.tx_timer.data = e1i_ts;
+	osmo_timer_schedule(&e1i_ts->sign.tx_timer, 0, 50000);
+
+	return 0;
+}
+
+
+static int invertbits = 1;
+
+static uint8_t flip_table[256];
+
+static void init_flip_bits(void)
+{
+        int i,k;
+
+        for (i = 0 ; i < 256 ; i++) {
+                uint8_t sample = 0 ;
+                for (k = 0; k<8; k++) {
+                        if ( i & 1 << k ) sample |= 0x80 >>  k;
+                }
+                flip_table[i] = sample;
+        }
+}
+
+static uint8_t * flip_buf_bits ( uint8_t * buf , int len)
+{
+        int i;
+        uint8_t * start = buf;
+
+        for (i = 0 ; i < len; i++) {
+                buf[i] = flip_table[(uint8_t)buf[i]];
+        }
+
+        return start;
+}
+
+#define D_BCHAN_TX_GRAN 160
+/* write to a B channel TS */
+static int handle_tsX_write(struct osmo_fd *bfd)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+	uint8_t tx_buf[D_BCHAN_TX_GRAN];
+	struct subch_mux *mx = &e1i_ts->trau.mux;
+	int ret;
+
+	ret = subchan_mux_out(mx, tx_buf, D_BCHAN_TX_GRAN);
+
+	if (ret != D_BCHAN_TX_GRAN) {
+		fprintf(stderr, "Huh, got ret of %d\n", ret);
+		if (ret < 0)
+			return ret;
+	}
+
+	DEBUGP(DMIB, "BCHAN TX: %s\n",
+		osmo_hexdump(tx_buf, D_BCHAN_TX_GRAN));
+
+	if (invertbits) {
+		flip_buf_bits(tx_buf, ret);
+	}
+
+	ret = write(bfd->fd, tx_buf, ret);
+	if (ret < D_BCHAN_TX_GRAN)
+		fprintf(stderr, "send returns %d instead of %d\n", ret,
+			D_BCHAN_TX_GRAN);
+
+	return ret;
+}
+
+#define D_TSX_ALLOC_SIZE (D_BCHAN_TX_GRAN)
+/* FIXME: read from a B channel TS */
+static int handle_tsX_read(struct osmo_fd *bfd)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+	struct msgb *msg = msgb_alloc(D_TSX_ALLOC_SIZE, "DAHDI TSx");
+	int ret;
+
+	if (!msg)
+		return -ENOMEM;
+
+	ret = read(bfd->fd, msg->data, D_TSX_ALLOC_SIZE);
+	if (ret < 0 || ret != D_TSX_ALLOC_SIZE) {
+		fprintf(stderr, "read error  %d %s\n", ret, strerror(errno));
+		return ret;
+	}
+
+	if (invertbits) {
+		flip_buf_bits(msg->data, ret);
+	}
+
+	msgb_put(msg, ret);
+
+	msg->l2h = msg->data;
+	DEBUGP(DMIB, "BCHAN RX: %s\n",
+		osmo_hexdump(msgb_l2(msg), ret));
+	ret = e1inp_rx_ts(e1i_ts, msg, 0, 0);
+	/* physical layer indicates that data has been sent,
+	 * we thus can send some more data */
+	ret = handle_tsX_write(bfd);
+	msgb_free(msg);
+
+	return ret;
+}
+
+/* callback from select.c in case one of the fd's can be read/written */
+static int dahdi_fd_cb(struct osmo_fd *bfd, unsigned int what)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	unsigned int idx = ts_nr-1;
+	struct e1inp_ts *e1i_ts = &line->ts[idx];
+	int rc = 0;
+
+	switch (e1i_ts->type) {
+	case E1INP_TS_TYPE_SIGN:
+		if (what & BSC_FD_EXCEPT)
+			handle_dahdi_exception(e1i_ts);
+		if (what & BSC_FD_READ)
+			rc = handle_ts1_read(bfd);
+		if (what & BSC_FD_WRITE)
+			rc = handle_ts1_write(bfd);
+		break;
+	case E1INP_TS_TYPE_TRAU:
+		if (what & BSC_FD_EXCEPT)
+			handle_dahdi_exception(e1i_ts);
+		if (what & BSC_FD_READ)
+			rc = handle_tsX_read(bfd);
+		if (what & BSC_FD_WRITE)
+			rc = handle_tsX_write(bfd);
+		/* We never include the DAHDI B-Channel FD into the
+		 * writeset, since it doesn't support poll() based
+		 * write flow control */
+		break;
+	default:
+		fprintf(stderr, "unknown E1 TS type %u\n", e1i_ts->type);
+		break;
+	}
+
+	return rc;
+}
+
+static int
+dahdi_e1_line_update(struct e1inp_line *line, enum e1inp_line_role role);
+
+struct e1inp_driver dahdi_driver = {
+	.name = "dahdi",
+	.want_write = ts_want_write,
+	.line_update = &dahdi_e1_line_update,
+};
+
+void dahdi_set_bufinfo(int fd, int as_sigchan)
+{
+	struct dahdi_bufferinfo bi;
+	int x = 0;
+
+	if (ioctl(fd, DAHDI_GET_BUFINFO, &bi)) {
+		fprintf(stderr, "Error getting bufinfo\n");
+		exit(-1);
+	}
+
+	if (as_sigchan) {
+		bi.numbufs = 4;
+		bi.bufsize = 512;
+	} else {
+		bi.numbufs = 8;
+		bi.bufsize = D_BCHAN_TX_GRAN;
+		bi.txbufpolicy = DAHDI_POLICY_WHEN_FULL;
+	}
+
+	if (ioctl(fd, DAHDI_SET_BUFINFO, &bi)) {
+		fprintf(stderr, "Error setting bufinfo\n");
+		exit(-1);
+	}
+
+	if (!as_sigchan) {
+		if (ioctl(fd, DAHDI_AUDIOMODE, &x)) {
+			fprintf(stderr, "Error setting bufinfo\n");
+			exit(-1);
+		}
+	} else {
+		int one = 1;
+		ioctl(fd, DAHDI_HDLCFCSMODE, &one);
+		/* we cannot reliably check for the ioctl return value here
+		 * as this command will fail if the slot _already_ was a
+		 * signalling slot before :( */
+	}
+}
+
+static int dahdi_e1_setup(struct e1inp_line *line)
+{
+	int ts, ret;
+
+	/* TS0 is CRC4, don't need any fd for it */
+	for (ts = 1; ts < NUM_E1_TS; ts++) {
+		unsigned int idx = ts-1;
+		char openstr[128];
+		struct e1inp_ts *e1i_ts = &line->ts[idx];
+		struct osmo_fd *bfd = &e1i_ts->driver.dahdi.fd;
+
+		bfd->data = line;
+		bfd->priv_nr = ts;
+		bfd->cb = dahdi_fd_cb;
+		snprintf(openstr, sizeof(openstr), "/dev/dahdi/%d", ts);
+
+		switch (e1i_ts->type) {
+		case E1INP_TS_TYPE_NONE:
+			continue;
+			break;
+		case E1INP_TS_TYPE_SIGN:
+			bfd->fd = open(openstr, O_RDWR | O_NONBLOCK);
+			if (bfd->fd == -1) {
+				fprintf(stderr, "%s could not open %s %s\n",
+					__func__, openstr, strerror(errno));
+				exit(-1);
+			}
+			bfd->when = BSC_FD_READ | BSC_FD_EXCEPT;
+			dahdi_set_bufinfo(bfd->fd, 1);
+			e1i_ts->driver.dahdi.lapd = lapd_instance_alloc(1, dahdi_write_msg, bfd);
+			break;
+		case E1INP_TS_TYPE_TRAU:
+			bfd->fd = open(openstr, O_RDWR | O_NONBLOCK);
+			if (bfd->fd == -1) {
+				fprintf(stderr, "%s could not open %s %s\n",
+					__func__, openstr, strerror(errno));
+				exit(-1);
+			}
+			dahdi_set_bufinfo(bfd->fd, 0);
+			/* We never include the DAHDI B-Channel FD into the
+			 * writeset, since it doesn't support poll() based
+			 * write flow control */
+			bfd->when = BSC_FD_READ | BSC_FD_EXCEPT;// | BSC_FD_WRITE;
+			break;
+		}
+
+		if (bfd->fd < 0) {
+			fprintf(stderr, "%s could not open %s %s\n",
+				__func__, openstr, strerror(errno));
+			return bfd->fd;
+		}
+
+		ret = osmo_fd_register(bfd);
+		if (ret < 0) {
+			fprintf(stderr, "could not register FD: %s\n",
+				strerror(ret));
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int
+dahdi_e1_line_update(struct e1inp_line *line, enum e1inp_line_role role)
+{
+	if (line->driver != &dahdi_driver)
+		return -EINVAL;
+
+	return dahdi_e1_setup(line);
+}
+
+int e1inp_dahdi_init(void)
+{
+	init_flip_bits();
+
+	/* register the driver with the core */
+	return e1inp_driver_register(&dahdi_driver);
+}
+
+#endif /* HAVE_DAHDI_USER_H */
diff --git a/src/input/hsl.c b/src/input/hsl.c
new file mode 100644
index 0000000..2ff9d39
--- /dev/null
+++ b/src/input/hsl.c
@@ -0,0 +1,296 @@
+/* OpenBSC Abis input driver for HSL Femto */
+
+/* (C) 2011 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2011 by On-Waves
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+/* HSL uses a much more primitive/simplified version of the IPA multiplex.
+ *
+ * They have taken out the nice parts like the ID_GET / ID_RESP for resolving
+ * the UNIT ID, as well as the keepalive ping/pong messages.  Furthermore, the
+ * Stream Identifiers are fixed on the BTS side (RSL always 0, OML always 0xff)
+ * and both OML+RSL share a single TCP connection.
+ *
+ * Other oddities include the encapsulation of BSSGP messages in the L3_INFO IE
+ * of RSL
+ */
+
+#include "internal.h"
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <time.h>
+#include <sys/fcntl.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <arpa/inet.h>
+
+#include <osmocom/core/select.h>
+#include <osmocom/gsm/tlv.h>
+#include <osmocom/core/msgb.h>
+#include <osmocom/gsm/abis/e1_input.h>
+#include <osmocom/core/logging.h>
+#include <osmocom/gsm/protocol/ipaccess.h>
+/*#include <openbsc/debug.h>
+#include <openbsc/gsm_data.h>
+#include <openbsc/abis_nm.h>
+#include <openbsc/abis_rsl.h>
+#include <openbsc/subchan_demux.h>
+#include <openbsc/e1_input.h>
+#include <openbsc/ipaccess.h>
+#include <openbsc/socket.h>
+#include <openbsc/signal.h> */
+#include <talloc.h>
+
+#define HSL_TCP_PORT	2500
+#define HSL_PROTO_DEBUG	0xdd
+
+#define PRIV_OML 1
+#define PRIV_RSL 2
+
+static void *tall_bsc_ctx;
+
+/* data structure for one E1 interface with A-bis */
+struct hsl_e1_handle {
+	struct osmo_fd listen_fd;
+	struct gsm_network *gsmnet;
+};
+
+static struct hsl_e1_handle *e1h;
+
+
+#define TS1_ALLOC_SIZE	900
+
+static int handle_ts1_read(struct osmo_fd *bfd)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+	struct msgb *msg;
+	int ret = 0, error;
+
+	msg = ipaccess_read_msg(bfd, &error);
+	if (!msg) {
+		if (e1i_ts->line->rx_err)
+			e1i_ts->line->rx_err(error);
+		if (error == 0) {
+			osmo_fd_unregister(bfd);
+			close(bfd->fd);
+			bfd->fd = -1;
+		}
+		return error;
+	}
+	DEBUGP(DMI, "RX %u: %s\n", ts_nr, osmo_hexdump(msgb_l2(msg), msgb_l2len(msg)));
+
+	/* XXX better use e1inp_rx_ts. */
+	if (e1i_ts->line->rx)
+		e1i_ts->line->rx(msg, e1i_ts);
+
+	return ret;
+}
+
+static int ts_want_write(struct e1inp_ts *e1i_ts)
+{
+	e1i_ts->driver.ipaccess.fd.when |= BSC_FD_WRITE;
+
+	return 0;
+}
+
+static void timeout_ts1_write(void *data)
+{
+	struct e1inp_ts *e1i_ts = (struct e1inp_ts *)data;
+
+	/* trigger write of ts1, due to tx delay timer */
+	ts_want_write(e1i_ts);
+}
+
+static int handle_ts1_write(struct osmo_fd *bfd)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+	struct e1inp_sign_link *sign_link;
+	struct msgb *msg;
+	uint8_t proto;
+	int ret;
+
+	bfd->when &= ~BSC_FD_WRITE;
+
+	/* get the next msg for this timeslot */
+	msg = e1inp_tx_ts(e1i_ts, &sign_link);
+	if (!msg) {
+		/* no message after tx delay timer */
+		return 0;
+	}
+
+	switch (sign_link->type) {
+	case E1INP_SIGN_OML:
+		proto = IPAC_PROTO_OML;
+#ifdef HSL_SR_1_0
+		/* HSL uses 0x81 for FOM for some reason */
+		if (msg->data[0] == ABIS_OM_MDISC_FOM)
+			msg->data[0] = ABIS_OM_MDISC_FOM | 0x01;
+#endif
+		break;
+	case E1INP_SIGN_RSL:
+		proto = IPAC_PROTO_RSL;
+		break;
+	default:
+		msgb_free(msg);
+		bfd->when |= BSC_FD_WRITE; /* come back for more msg */
+		return -EINVAL;
+	}
+
+	msg->l2h = msg->data;
+	ipaccess_prepend_header(msg, sign_link->tei);
+
+	DEBUGP(DMI, "TX %u: %s\n", ts_nr, osmo_hexdump(msg->l2h, msgb_l2len(msg)));
+
+	ret = send(bfd->fd, msg->data, msg->len, 0);
+	msgb_free(msg);
+
+	/* set tx delay timer for next event */
+	e1i_ts->sign.tx_timer.cb = timeout_ts1_write;
+	e1i_ts->sign.tx_timer.data = e1i_ts;
+
+	/* Reducing this might break the nanoBTS 900 init. */
+	osmo_timer_schedule(&e1i_ts->sign.tx_timer, 0, e1i_ts->sign.delay);
+
+	return ret;
+}
+
+/* callback from select.c in case one of the fd's can be read/written */
+static int hsl_fd_cb(struct osmo_fd *bfd, unsigned int what)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	unsigned int idx = ts_nr-1;
+	struct e1inp_ts *e1i_ts;
+	int rc = 0;
+
+	/* In case of early RSL we might not yet have a line */
+
+	if (line)
+		e1i_ts = &line->ts[idx];
+
+	if (!line || e1i_ts->type == E1INP_TS_TYPE_SIGN) {
+		if (what & BSC_FD_READ)
+			rc = handle_ts1_read(bfd);
+		if (what & BSC_FD_WRITE)
+			rc = handle_ts1_write(bfd);
+	} else
+		LOGP(DINP, LOGL_ERROR, "unknown E1 TS type %u\n", e1i_ts->type);
+
+	return rc;
+}
+
+static int hsl_line_update(struct e1inp_line *line, enum e1inp_line_role role);
+
+struct e1inp_driver hsl_driver = {
+	.name = "hsl",
+	.want_write = ts_want_write,
+	.line_update = hsl_line_update,
+	.default_delay = 0,
+};
+
+/* callback of the OML listening filedescriptor */
+static int listen_fd_cb(struct osmo_fd *listen_bfd, unsigned int what)
+{
+	int ret;
+	int idx = 0;
+	int i;
+	struct e1inp_line *line = listen_bfd->data;
+	struct e1inp_ts *e1i_ts;
+	struct osmo_fd *bfd;
+	struct sockaddr_in sa;
+	socklen_t sa_len = sizeof(sa);
+
+	if (!(what & BSC_FD_READ))
+		return 0;
+
+	ret = accept(listen_bfd->fd, (struct sockaddr *) &sa, &sa_len);
+	if (ret < 0) {
+		perror("accept");
+		return ret;
+	}
+	LOGP(DINP, LOGL_NOTICE, "accept()ed new HSL link from %s\n",
+		inet_ntoa(sa.sin_addr));
+
+	/* create virrtual E1 timeslots for signalling */
+	e1inp_ts_config_sign(&line->ts[1-1], line);
+
+	/* initialize the fds */
+	for (i = 0; i < ARRAY_SIZE(line->ts); ++i)
+		line->ts[i].driver.ipaccess.fd.fd = -1;
+
+	e1i_ts = &line->ts[idx];
+
+	bfd = &e1i_ts->driver.ipaccess.fd;
+	bfd->fd = ret;
+	bfd->data = line;
+	bfd->priv_nr = PRIV_OML;
+	bfd->cb = hsl_fd_cb;
+	bfd->when = BSC_FD_READ;
+	ret = osmo_fd_register(bfd);
+	if (ret < 0) {
+		LOGP(DINP, LOGL_ERROR, "could not register FD\n");
+		close(bfd->fd);
+		talloc_free(line);
+		return ret;
+	}
+
+        return ret;
+}
+
+static int
+hsl_line_update(struct e1inp_line *line, enum e1inp_line_role role)
+{
+	int ret = -ENOENT;
+
+	switch(role) {
+	case E1INP_LINE_R_BSC:
+		ret = make_sock(&e1h->listen_fd, IPPROTO_TCP, INADDR_ANY,
+				HSL_TCP_PORT, 0, listen_fd_cb, line);
+		break;
+	case E1INP_LINE_R_BTS:
+		/* XXX: not implemented yet. */
+		break;
+	default:
+		break;
+	}
+	return ret;
+}
+
+int hsl_setup(struct gsm_network *gsmnet)
+{
+	e1h->gsmnet = gsmnet;
+	return 0;
+}
+
+void e1inp_hsl_init(void)
+{
+	e1h = talloc_zero(tall_bsc_ctx, struct hsl_e1_handle);
+	if (!e1h)
+		return;
+
+	e1inp_driver_register(&hsl_driver);
+}
diff --git a/src/input/ipaccess.c b/src/input/ipaccess.c
new file mode 100644
index 0000000..5777d56
--- /dev/null
+++ b/src/input/ipaccess.c
@@ -0,0 +1,499 @@
+/* OpenBSC Abis input driver for ip.access */
+
+/* (C) 2009 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2010 by Holger Hans Peter Freyther
+ * (C) 2010 by On-Waves
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "internal.h"
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <time.h>
+#include <sys/fcntl.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <arpa/inet.h>
+
+#include <osmocom/core/select.h>
+#include <osmocom/gsm/tlv.h>
+#include <osmocom/core/msgb.h>
+#include <osmocom/core/logging.h>
+#include <talloc.h>
+#include <osmocom/gsm/abis/e1_input.h>
+#include <osmocom/gsm/abis/ipaccess.h>
+/*#include <openbsc/debug.h>
+#include <openbsc/gsm_data.h>
+#include <openbsc/abis_nm.h>
+#include <openbsc/abis_rsl.h>
+#include <openbsc/subchan_demux.h>
+#include <openbsc/e1_input.h>
+#include <openbsc/ipaccess.h>
+#include <openbsc/socket.h>
+#include <openbsc/signal.h> */
+
+#define PRIV_OML 1
+#define PRIV_RSL 2
+
+static void *tall_bsc_ctx;
+
+/* data structure for one E1 interface with A-bis */
+struct ia_e1_handle {
+	struct osmo_fd listen_fd;
+	struct osmo_fd rsl_listen_fd;
+	struct gsm_network *gsmnet;
+};
+
+static struct ia_e1_handle *e1h;
+
+
+#define TS1_ALLOC_SIZE	900
+
+/*
+ * Common propietary IPA messages:
+ *      - PONG: in reply to PING.
+ *      - ID_REQUEST: first messages once OML has been established.
+ *      - ID_ACK: in reply to ID_ACK.
+ */
+const uint8_t ipa_pong_msg[] = {
+	0, 1, IPAC_PROTO_IPACCESS, IPAC_MSGT_PONG
+};
+
+const uint8_t ipa_id_ack_msg[] = {
+	0, 1, IPAC_PROTO_IPACCESS, IPAC_MSGT_ID_ACK
+};
+
+const uint8_t ipa_id_req_msg[] = {
+	0, 17, IPAC_PROTO_IPACCESS, IPAC_MSGT_ID_GET,
+	0x01, IPAC_IDTAG_UNIT,
+	0x01, IPAC_IDTAG_MACADDR,
+	0x01, IPAC_IDTAG_LOCATION1,
+	0x01, IPAC_IDTAG_LOCATION2,
+	0x01, IPAC_IDTAG_EQUIPVERS,
+	0x01, IPAC_IDTAG_SWVERSION,
+	0x01, IPAC_IDTAG_UNITNAME,
+	0x01, IPAC_IDTAG_SERNR,
+};
+
+static int ipaccess_send(int fd, const void *msg, size_t msglen)
+{
+	int ret;
+
+	ret = write(fd, msg, msglen);
+	if (ret < 0)
+		return ret;
+	if (ret < msglen) {
+		LOGP(DINP, LOGL_ERROR, "ipaccess_send: short write\n");
+		return -EIO;
+	}
+	return ret;
+}
+
+int ipaccess_send_pong(int fd)
+{
+	return ipaccess_send(fd, ipa_pong_msg, sizeof(ipa_pong_msg));
+}
+
+int ipaccess_send_id_ack(int fd)
+{
+	return ipaccess_send(fd, ipa_id_ack_msg, sizeof(ipa_id_ack_msg));
+}
+
+int ipaccess_send_id_req(int fd)
+{
+	return ipaccess_send(fd, ipa_id_req_msg, sizeof(ipa_id_req_msg));
+}
+
+/*
+ * read one ipa message from the socket
+ * return NULL in case of error
+ */
+struct msgb *ipaccess_read_msg(struct osmo_fd *bfd, int *error)
+{
+	struct msgb *msg = msgb_alloc(TS1_ALLOC_SIZE, "Abis/IP");
+	struct ipaccess_head *hh;
+	int len, ret = 0;
+
+	if (!msg) {
+		*error = -ENOMEM;
+		return NULL;
+	}
+
+	/* first read our 3-byte header */
+	hh = (struct ipaccess_head *) msg->data;
+	ret = recv(bfd->fd, msg->data, sizeof(*hh), 0);
+	if (ret == 0) {
+		msgb_free(msg);
+		*error = ret;
+		return NULL;
+	} else if (ret != sizeof(*hh)) {
+		if (errno != EAGAIN)
+			LOGP(DINP, LOGL_ERROR, "recv error %d %s\n", ret, strerror(errno));
+		msgb_free(msg);
+		*error = ret;
+		return NULL;
+	}
+
+	msgb_put(msg, ret);
+
+	/* then read te length as specified in header */
+	msg->l2h = msg->data + sizeof(*hh);
+	len = ntohs(hh->len);
+
+	if (len < 0 || TS1_ALLOC_SIZE < len + sizeof(*hh)) {
+		LOGP(DINP, LOGL_ERROR, "Can not read this packet. %d avail\n", len);
+		msgb_free(msg);
+		*error = -EIO;
+		return NULL;
+	}
+
+	ret = recv(bfd->fd, msg->l2h, len, 0);
+	if (ret < len) {
+		LOGP(DINP, LOGL_ERROR, "short read! Got %d from %d\n", ret, len);
+		msgb_free(msg);
+		*error = -EIO;
+		return NULL;
+	}
+	msgb_put(msg, ret);
+
+	return msg;
+}
+
+static int handle_ts1_read(struct osmo_fd *bfd)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+	struct msgb *msg;
+	int ret = 0, error;
+
+	msg = ipaccess_read_msg(bfd, &error);
+	if (!msg) {
+		if (e1i_ts->line->rx_err)
+			e1i_ts->line->rx_err(error);
+		if (error == 0) {
+		        osmo_fd_unregister(bfd);
+		        close(bfd->fd);
+		        bfd->fd = -1;
+		}
+		return error;
+	}
+	DEBUGP(DMI, "RX %u: %s\n", ts_nr, osmo_hexdump(msgb_l2(msg), msgb_l2len(msg)));
+
+	/* XXX better use e1inp_ts_rx. */
+
+	if (e1i_ts->line->rx)
+		e1i_ts->line->rx(msg, e1i_ts);
+	return ret;
+}
+
+void ipaccess_prepend_header_ext(struct msgb *msg, int proto)
+{
+	struct ipaccess_head_ext *hh_ext;
+
+	/* prepend the osmo ip.access header extension */
+	hh_ext = (struct ipaccess_head_ext *) msgb_push(msg, sizeof(*hh_ext));
+	hh_ext->proto = proto;
+}
+
+void ipaccess_prepend_header(struct msgb *msg, int proto)
+{
+	struct ipaccess_head *hh;
+
+	/* prepend the ip.access header */
+	hh = (struct ipaccess_head *) msgb_push(msg, sizeof(*hh));
+	hh->len = htons(msg->len - sizeof(*hh));
+	hh->proto = proto;
+}
+
+static int ts_want_write(struct e1inp_ts *e1i_ts)
+{
+	e1i_ts->driver.ipaccess.fd.when |= BSC_FD_WRITE;
+
+	return 0;
+}
+
+static void timeout_ts1_write(void *data)
+{
+	struct e1inp_ts *e1i_ts = (struct e1inp_ts *)data;
+
+	/* trigger write of ts1, due to tx delay timer */
+	ts_want_write(e1i_ts);
+}
+
+static int handle_ts1_write(struct osmo_fd *bfd)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+	struct e1inp_sign_link *sign_link;
+	struct msgb *msg;
+	uint8_t proto;
+	int ret;
+
+	bfd->when &= ~BSC_FD_WRITE;
+
+	/* get the next msg for this timeslot */
+	msg = e1inp_tx_ts(e1i_ts, &sign_link);
+	if (!msg) {
+		/* no message after tx delay timer */
+		return 0;
+	}
+
+	switch (sign_link->type) {
+	case E1INP_SIGN_OML:
+		proto = IPAC_PROTO_OML;
+		break;
+	case E1INP_SIGN_RSL:
+		proto = IPAC_PROTO_RSL;
+		break;
+	default:
+		msgb_free(msg);
+		bfd->when |= BSC_FD_WRITE; /* come back for more msg */
+		return -EINVAL;
+	}
+
+	msg->l2h = msg->data;
+	ipaccess_prepend_header(msg, sign_link->tei);
+
+	DEBUGP(DMI, "TX %u: %s\n", ts_nr, osmo_hexdump(msg->l2h, msgb_l2len(msg)));
+
+	ret = send(bfd->fd, msg->data, msg->len, 0);
+	msgb_free(msg);
+
+	/* set tx delay timer for next event */
+	e1i_ts->sign.tx_timer.cb = timeout_ts1_write;
+	e1i_ts->sign.tx_timer.data = e1i_ts;
+
+	/* Reducing this might break the nanoBTS 900 init. */
+	osmo_timer_schedule(&e1i_ts->sign.tx_timer, 0, e1i_ts->sign.delay);
+
+	return ret;
+}
+
+/* callback from select.c in case one of the fd's can be read/written */
+static int ipaccess_fd_cb(struct osmo_fd *bfd, unsigned int what)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	unsigned int idx = ts_nr-1;
+	struct e1inp_ts *e1i_ts;
+	int rc = 0;
+
+	/* In case of early RSL we might not yet have a line */
+
+	if (line)
+ 		e1i_ts = &line->ts[idx];
+
+	if (!line || e1i_ts->type == E1INP_TS_TYPE_SIGN) {
+		if (what & BSC_FD_READ)
+			rc = handle_ts1_read(bfd);
+		if (what & BSC_FD_WRITE)
+			rc = handle_ts1_write(bfd);
+	} else
+		LOGP(DINP, LOGL_ERROR, "unknown E1 TS type %u\n", e1i_ts->type);
+
+	return rc;
+}
+
+static int
+ipaccess_line_update(struct e1inp_line *line, enum e1inp_line_role role);
+
+struct e1inp_driver ipaccess_driver = {
+	.name = "ipa",
+	.want_write = ts_want_write,
+	.line_update = ipaccess_line_update,
+	.default_delay = 0,
+};
+
+/* callback of the OML listening filedescriptor */
+static int listen_fd_cb(struct osmo_fd *listen_bfd, unsigned int what)
+{
+	int ret;
+	int idx = 0;
+	int i;
+	struct e1inp_line *line = listen_bfd->data;
+	struct e1inp_ts *e1i_ts;
+	struct osmo_fd *bfd;
+	struct sockaddr_in sa;
+	socklen_t sa_len = sizeof(sa);
+
+	if (!(what & BSC_FD_READ))
+		return 0;
+
+	ret = accept(listen_bfd->fd, (struct sockaddr *) &sa, &sa_len);
+	if (ret < 0) {
+		perror("accept");
+		return ret;
+	}
+	LOGP(DINP, LOGL_NOTICE, "accept()ed new OML link from %s\n",
+		inet_ntoa(sa.sin_addr));
+
+	/* create virrtual E1 timeslots for signalling */
+	e1inp_ts_config_sign(&line->ts[1-1], line);
+
+	/* initialize the fds */
+	for (i = 0; i < ARRAY_SIZE(line->ts); ++i)
+		line->ts[i].driver.ipaccess.fd.fd = -1;
+
+	e1i_ts = &line->ts[idx];
+
+	bfd = &e1i_ts->driver.ipaccess.fd;
+	bfd->fd = ret;
+	bfd->data = line;
+	bfd->priv_nr = PRIV_OML;
+	bfd->cb = ipaccess_fd_cb;
+	bfd->when = BSC_FD_READ;
+	ret = osmo_fd_register(bfd);
+	if (ret < 0) {
+		LOGP(DINP, LOGL_ERROR, "could not register FD\n");
+		close(bfd->fd);
+		return ret;
+	}
+
+	/* Request ID. FIXME: request LOCATION, HW/SW VErsion, Unit Name, Serno */
+	ret = ipaccess_send_id_req(bfd->fd);
+
+        return ret;
+}
+
+static int rsl_listen_fd_cb(struct osmo_fd *listen_bfd, unsigned int what)
+{
+	struct sockaddr_in sa;
+	socklen_t sa_len = sizeof(sa);
+	struct osmo_fd *bfd;
+	int ret;
+
+	if (!(what & BSC_FD_READ))
+		return 0;
+
+	bfd = talloc_zero(tall_bsc_ctx, struct osmo_fd);
+	if (!bfd)
+		return -ENOMEM;
+
+	/* Some BTS has connected to us, but we don't know yet which line
+	 * (as created by the OML link) to associate it with.  Thus, we
+	 * allocate a temporary bfd until we have received ID from BTS */
+
+	bfd->fd = accept(listen_bfd->fd, (struct sockaddr *) &sa, &sa_len);
+	if (bfd->fd < 0) {
+		perror("accept");
+		return bfd->fd;
+	}
+	LOGP(DINP, LOGL_NOTICE, "accept()ed new RSL link from %s\n", inet_ntoa(sa.sin_addr));
+	bfd->priv_nr = PRIV_RSL;
+	bfd->cb = ipaccess_fd_cb;
+	bfd->when = BSC_FD_READ;
+	ret = osmo_fd_register(bfd);
+	if (ret < 0) {
+		LOGP(DINP, LOGL_ERROR, "could not register FD\n");
+		close(bfd->fd);
+		talloc_free(bfd);
+		return ret;
+	}
+	/* Request ID. FIXME: request LOCATION, HW/SW VErsion, Unit Name, Serno */
+	ret = ipaccess_send_id_req(bfd->fd);
+
+	return 0;
+}
+
+static int
+ipaccess_line_update(struct e1inp_line *line, enum e1inp_line_role role)
+{
+	int ret = -ENOENT;
+
+	switch(role) {
+	case E1INP_LINE_R_BSC:
+		/* Listen for OML connections */
+		ret = make_sock(&e1h->listen_fd, IPPROTO_TCP, INADDR_ANY,
+				IPA_TCP_PORT_OML, 0, listen_fd_cb, line);
+		if (ret < 0)
+			return ret;
+
+		/* Listen for RSL connections */
+		ret = make_sock(&e1h->rsl_listen_fd, IPPROTO_TCP, INADDR_ANY,
+				IPA_TCP_PORT_RSL, 0, rsl_listen_fd_cb, NULL);
+		if (ret < 0)
+			return ret;
+		break;
+	case E1INP_LINE_R_BTS:
+		/* XXX: no implemented yet. */
+		break;
+	default:
+		break;
+	}
+	return ret;
+}
+
+/* Actively connect to a BTS.  Currently used by ipaccess-config.c */
+int ipaccess_connect(struct e1inp_line *line, struct sockaddr_in *sa)
+{
+	struct e1inp_ts *e1i_ts = &line->ts[0];
+	struct osmo_fd *bfd = &e1i_ts->driver.ipaccess.fd;
+	int ret, on = 1;
+
+	bfd->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
+	bfd->cb = ipaccess_fd_cb;
+	bfd->when = BSC_FD_READ | BSC_FD_WRITE;
+	bfd->data = line;
+	bfd->priv_nr = PRIV_OML;
+
+	if (bfd->fd < 0) {
+		LOGP(DINP, LOGL_ERROR, "could not create TCP socket.\n");
+		return -EIO;
+	}
+
+	setsockopt(bfd->fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
+
+	ret = connect(bfd->fd, (struct sockaddr *) sa, sizeof(*sa));
+	if (ret < 0) {
+		LOGP(DINP, LOGL_ERROR, "could not connect socket\n");
+		close(bfd->fd);
+		return ret;
+	}
+
+	ret = osmo_fd_register(bfd);
+	if (ret < 0) {
+		close(bfd->fd);
+		return ret;
+	}
+
+	line->driver = &ipaccess_driver;
+
+        return ret;
+	//return e1inp_line_register(line);
+}
+
+int ipaccess_setup(struct gsm_network *gsmnet)
+{
+	e1h->gsmnet = gsmnet;
+	return 0;
+}
+
+void e1inp_ipaccess_init(void)
+{
+	e1h = talloc_zero(tall_bsc_ctx, struct ia_e1_handle);
+	if (!e1h)
+		return;
+
+	e1inp_driver_register(&ipaccess_driver);
+}
diff --git a/src/input/lapd.c b/src/input/lapd.c
new file mode 100644
index 0000000..060edb6
--- /dev/null
+++ b/src/input/lapd.c
@@ -0,0 +1,713 @@
+/* OpenBSC minimal LAPD implementation */
+
+/* (C) 2009 by oystein@homelien.no
+ * (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org>
+ * (C) 2010 by Digium and Matthew Fredrickson <creslin@digium.com>
+ * (C) 2011 by Harald Welte <laforge@gnumonks.org>
+ *
+ * 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 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.
+ *
+ */
+
+/* TODO:
+	* detect RR timeout and set SAP state back to SABM_RETRANSMIT
+	* use of value_string
+	* further code cleanup (spaghetti)
+ */
+
+#include "internal.h"
+
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include <errno.h>
+
+#include "lapd.h"
+
+#include <osmocom/core/linuxlist.h>
+#include <osmocom/core/logging.h>
+#include <talloc.h>
+#include <osmocom/core/msgb.h>
+#include <osmocom/core/timer.h>
+//#include <openbsc/debug.h>
+
+#define SABM_INTERVAL		0, 300000
+
+typedef enum {
+	LAPD_TEI_NONE = 0,
+	LAPD_TEI_ASSIGNED,
+	LAPD_TEI_ACTIVE,
+} lapd_tei_state;
+
+const char *lapd_tei_states[] = {
+	"NONE",
+	"ASSIGNED",
+	"ACTIVE",
+};
+
+typedef enum {
+	LAPD_TYPE_NONE = 0,
+
+	LAPD_TYPE_I,
+	LAPD_TYPE_S,
+	LAPD_TYPE_U,
+} lapd_msg_type;
+
+typedef enum {
+	/* commands/responses */
+	LAPD_CMD_NONE = 0,
+
+	LAPD_CMD_I,
+	LAPD_CMD_RR,
+	LAPD_CMD_RNR,
+	LAPD_CMD_REJ,
+
+	LAPD_CMD_SABME,
+	LAPD_CMD_DM,
+	LAPD_CMD_UI,
+	LAPD_CMD_DISC,
+	LAPD_CMD_UA,
+	LAPD_CMD_FRMR,
+	LAPD_CMD_XID,
+} lapd_cmd_type;
+
+const char *lapd_cmd_types[] = {
+	"NONE",
+
+	"I",
+	"RR",
+	"RNR",
+	"REJ",
+
+	"SABME",
+	"DM",
+	"UI",
+	"DISC",
+	"UA",
+	"FRMR",
+	"XID",
+
+};
+
+enum lapd_sap_state {
+	SAP_STATE_INACTIVE,
+	SAP_STATE_SABM_RETRANS,
+	SAP_STATE_ACTIVE,
+};
+
+const char *lapd_sap_states[] = {
+	"INACTIVE",
+	"SABM_RETRANS",
+	"ACTIVE",
+};
+
+const char *lapd_msg_types = "?ISU";
+
+/* structure representing an allocated TEI within a LAPD instance */
+struct lapd_tei {
+	struct llist_head list;
+	struct lapd_instance *li;
+	uint8_t tei;
+	lapd_tei_state state;
+
+	struct llist_head sap_list;
+};
+
+/* Structure representing a SAP within a TEI. We use this for TE-mode to
+ * re-transmit SABM */
+struct lapd_sap {
+	struct llist_head list;
+	struct lapd_tei *tei;
+	uint8_t sapi;
+	enum lapd_sap_state state;
+
+	/* A valid N(R) value is one that is in the range V(A) ≤ N(R) ≤ V(S). */
+	int vs;			/* next to be transmitted */
+	int va;			/* last acked by peer */
+	int vr;			/* next expected to be received */
+
+	struct osmo_timer_list sabme_timer;	/* timer to re-transmit SABM message */
+};
+
+/* 3.5.2.2   Send state variable V(S)
+ * Each point-to-point data link connection endpoint shall have an associated V(S) when using I frame
+ * commands. V(S) denotes the sequence number of the next I frame to be transmitted. The V(S) can
+ * take on the value 0 through n minus 1. The value of V(S) shall be incremented by 1 with each
+ * successive I frame transmission, and shall not exceed V(A) by more than the maximum number of
+ * outstanding I frames k. The value of k may be in the range of 1 ≤ k ≤ 127.
+ *
+ * 3.5.2.3   Acknowledge state variable V(A)
+ * Each point-to-point data link connection endpoint shall have an associated V(A) when using I frame
+ * commands and supervisory frame commands/responses. V(A) identifies the last I frame that has been
+ * acknowledged by its peer [V(A) − 1 equals the N(S) of the last acknowledged I frame]. V(A) can
+ * take on the value 0 through n minus 1. The value of V(A) shall be updated by the valid N(R) values
+ * received from its peer (see 3.5.2.6). A valid N(R) value is one that is in the range V(A) ≤ N(R) ≤
+ * V(S).
+ *
+ * 3.5.2.5    Receive state variable V(R)
+ * Each point-to-point data link connection endpoint shall have an associated V(R) when using I frame
+ * commands and supervisory frame commands/responses. V(R) denotes the sequence number of the
+ * next in-sequence I frame expected to be received. V(R) can take on the value 0 through n minus 1.
+ * The value of V(R) shall be incremented by one with the receipt of an error-free, in-sequence I frame
+ * whose N(S) equals V(R).
+ */
+#define	LAPD_NS(sap) (sap->vs)
+#define	LAPD_NR(sap) (sap->vr)
+
+/* 3.5.2.4    Send sequence number N(S)
+ * Only I frames contain N(S), the send sequence number of transmitted I frames. At the time that an in-
+ * sequence I frame is designated for transmission, the value of N(S) is set equal to V(S).
+ *
+ * 3.5.2.6    Receive sequence number N(R)
+ * All I frames and supervisory frames contain N(R), the expected send sequence number of the next
+ * received I frame. At the time that a frame of the above types is designated for transmission, the value
+ * of N(R) is set equal to V(R). N(R) indicates that the data link layer entity transmitting the N(R) has
+ * correctly received all I frames numbered up to and including N(R) − 1.
+ */
+
+/* Resolve TEI structure from given numeric TEI */
+static struct lapd_tei *teip_from_tei(struct lapd_instance *li, uint8_t tei)
+{
+	struct lapd_tei *lt;
+
+	llist_for_each_entry(lt, &li->tei_list, list) {
+		if (lt->tei == tei)
+			return lt;
+	}
+	return NULL;
+};
+
+static void lapd_tei_set_state(struct lapd_tei *teip, int newstate)
+{
+	DEBUGP(DMI, "state change on TEI %d: %s -> %s\n", teip->tei,
+		   lapd_tei_states[teip->state], lapd_tei_states[newstate]);
+	teip->state = newstate;
+};
+
+/* Allocate a new TEI */
+struct lapd_tei *lapd_tei_alloc(struct lapd_instance *li, uint8_t tei)
+{
+	struct lapd_tei *teip;
+
+	teip = talloc_zero(li, struct lapd_tei);
+	if (!teip)
+		return NULL;
+
+	teip->li = li;
+	teip->tei = tei;
+	llist_add(&teip->list, &li->tei_list);
+	INIT_LLIST_HEAD(&teip->sap_list);
+
+	lapd_tei_set_state(teip, LAPD_TEI_ASSIGNED);
+
+	return teip;
+}
+
+/* Find a SAP within a given TEI */
+static struct lapd_sap *lapd_sap_find(struct lapd_tei *teip, uint8_t sapi)
+{
+	struct lapd_sap *sap;
+
+	llist_for_each_entry(sap, &teip->sap_list, list) {
+		if (sap->sapi == sapi)
+			return sap;
+	}
+
+	return NULL;
+}
+
+static void sabme_timer_cb(void *_sap);
+
+/* Allocate a new SAP within a given TEI */
+static struct lapd_sap *lapd_sap_alloc(struct lapd_tei *teip, uint8_t sapi)
+{
+	struct lapd_sap *sap = talloc_zero(teip, struct lapd_sap);
+
+	LOGP(DMI, LOGL_INFO, "Allocating SAP for SAPI=%u / TEI=%u\n",
+		sapi, teip->tei);
+
+	sap->sapi = sapi;
+	sap->tei = teip;
+	sap->sabme_timer.cb = &sabme_timer_cb;
+	sap->sabme_timer.data = sap;
+
+	llist_add(&sap->list, &teip->sap_list);
+
+	return sap;
+}
+
+static void lapd_sap_set_state(struct lapd_tei *teip, uint8_t sapi,
+				enum lapd_sap_state newstate)
+{
+	struct lapd_sap *sap = lapd_sap_find(teip, sapi);
+	if (!sap)
+		return;
+
+	DEBUGP(DMI, "state change on TEI %u / SAPI %u: %s -> %s\n", teip->tei,
+		sapi, lapd_sap_states[sap->state], lapd_sap_states[newstate]);
+	switch (sap->state) {
+	case SAP_STATE_SABM_RETRANS:
+		if (newstate != SAP_STATE_SABM_RETRANS)
+			osmo_timer_del(&sap->sabme_timer);
+		break;
+	default:
+		if (newstate == SAP_STATE_SABM_RETRANS)
+			osmo_timer_schedule(&sap->sabme_timer, SABM_INTERVAL);
+		break;
+	}
+
+	sap->state = newstate;
+};
+
+/* Input function into TEI manager */
+static void lapd_tei_receive(struct lapd_instance *li, uint8_t *data, int len)
+{
+	uint8_t entity = data[0];
+	uint8_t ref = data[1];
+	uint8_t mt = data[3];
+	uint8_t action = data[4] >> 1;
+	uint8_t e = data[4] & 1;
+	uint8_t resp[8];
+	struct lapd_tei *teip;
+
+	DEBUGP(DMI, "TEIMGR: entity %x, ref %x, mt %x, action %x, e %x\n", entity, ref, mt, action, e);
+
+	switch (mt) {
+	case 0x01:	/* IDENTITY REQUEST */
+		DEBUGP(DMI, "TEIMGR: identity request for TEI %u\n", action);
+
+		teip = teip_from_tei(li, action);
+		if (!teip) {
+			LOGP(DMI, LOGL_INFO, "TEI MGR: New TEI %u\n", action);
+			teip = lapd_tei_alloc(li, action);
+		}
+
+		/* Send ACCEPT */
+		memmove(resp, "\xfe\xff\x03\x0f\x00\x00\x02\x00", 8);
+		resp[7] = (action << 1) | 1;
+		li->transmit_cb(resp, 8, li->cbdata);
+
+		if (teip->state == LAPD_TEI_NONE)
+			lapd_tei_set_state(teip, LAPD_TEI_ASSIGNED);
+		break;
+	default:
+		LOGP(DMI, LOGL_NOTICE, "TEIMGR: unknown mt %x action %x\n",
+		     mt, action);
+		break;
+	};
+};
+
+/* General input function for any data received for this LAPD instance */
+uint8_t *lapd_receive(struct lapd_instance *li, uint8_t * data, unsigned int len,
+		      int *ilen, lapd_mph_type *prim)
+{
+	uint8_t sapi, cr, tei, command;
+	int pf, ns, nr;
+	uint8_t *contents;
+	struct lapd_tei *teip;
+	struct lapd_sap *sap;
+
+	uint8_t resp[8];
+	int l = 0;
+
+	*ilen = 0;
+	*prim = 0;
+
+	if (len < 2) {
+		DEBUGP(DMI, "len %d < 2\n", len);
+		return NULL;
+	};
+
+	if ((data[0] & 1) != 0 || (data[1] & 1) != 1) {
+		DEBUGP(DMI, "address field %x/%x not well formed\n", data[0],
+			   data[1]);
+		return NULL;
+	};
+
+	sapi = data[0] >> 2;
+	cr = (data[0] >> 1) & 1;
+	tei = data[1] >> 1;
+	command = li->network_side ^ cr;
+	//DEBUGP(DMI, "  address sapi %x tei %d cmd %d cr %d\n", sapi, tei, command, cr);
+
+	if (len < 3) {
+		DEBUGP(DMI, "len %d < 3\n", len);
+		return NULL;
+	};
+
+	lapd_msg_type typ = 0;
+	lapd_cmd_type cmd = 0;
+	pf = -1;
+	ns = -1;
+	nr = -1;
+	if ((data[2] & 1) == 0) {
+		typ = LAPD_TYPE_I;
+		assert(len >= 4);
+		ns = data[2] >> 1;
+		nr = data[3] >> 1;
+		pf = data[3] & 1;
+		cmd = LAPD_CMD_I;
+	} else if ((data[2] & 3) == 1) {
+		typ = LAPD_TYPE_S;
+		assert(len >= 4);
+		nr = data[3] >> 1;
+		pf = data[3] & 1;
+		switch (data[2]) {
+		case 0x1:
+			cmd = LAPD_CMD_RR;
+			break;
+		case 0x5:
+			cmd = LAPD_CMD_RNR;
+			break;
+		case 0x9:
+			cmd = LAPD_CMD_REJ;
+			break;
+		default:
+			LOGP(DMI, LOGL_ERROR, "unknown LAPD S cmd %x\n", data[2]);
+			return NULL;
+		};
+	} else if ((data[2] & 3) == 3) {
+		typ = LAPD_TYPE_U;
+		pf = (data[2] >> 4) & 1;
+		int val = data[2] & ~(1 << 4);
+		switch (val) {
+		case 0x6f:
+			cmd = LAPD_CMD_SABME;
+			break;
+		case 0x0f:
+			cmd = LAPD_CMD_DM;
+			break;
+		case 0x03:
+			cmd = LAPD_CMD_UI;
+			break;
+		case 0x43:
+			cmd = LAPD_CMD_DISC;
+			break;
+		case 0x63:
+			cmd = LAPD_CMD_UA;
+			break;
+		case 0x87:
+			cmd = LAPD_CMD_FRMR;
+			break;
+		case 0xaf:
+			cmd = LAPD_CMD_XID;
+			break;
+
+		default:
+			LOGP(DMI, LOGL_ERROR, "unknown U cmd %x "
+			     "(pf %x data %x)\n", val, pf, data[2]);
+			return NULL;
+		};
+	};
+
+	contents = &data[4];
+	if (typ == LAPD_TYPE_U)
+		contents--;
+	*ilen = len - (contents - data);
+
+	if (tei == 127)
+		lapd_tei_receive(li, contents, *ilen);
+
+	teip = teip_from_tei(li, tei);
+	if (!teip) {
+		LOGP(DMI, LOGL_NOTICE, "Unknown TEI %u\n", tei);
+		return NULL;
+	}
+
+	sap = lapd_sap_find(teip, sapi);
+	if (!sap) {
+		LOGP(DMI, LOGL_INFO, "No SAP for TEI=%u / SAPI=%u, "
+			"allocating\n", tei, sapi);
+		sap = lapd_sap_alloc(teip, sapi);
+	}
+
+	DEBUGP(DMI, "<- %c %s sapi %x tei %3d cmd %x pf %x ns %3d nr %3d "
+	     "ilen %d teip %p vs %d va %d vr %d len %d\n",
+	     lapd_msg_types[typ], lapd_cmd_types[cmd], sapi, tei, command, pf,
+	     ns, nr, *ilen, teip, sap->vs, sap->va, sap->vr, len);
+
+	switch (cmd) {
+	case LAPD_CMD_I:
+		if (ns != sap->vr) {
+			DEBUGP(DMI, "ns %d != vr %d\n", ns, sap->vr);
+			if (ns == ((sap->vr - 1) & 0x7f)) {
+				DEBUGP(DMI, "DOUBLE FRAME, ignoring\n");
+				cmd = 0;	// ignore
+			} else {
+				assert(0);
+			};
+		} else {
+			//printf("IN SEQUENCE\n");
+			sap->vr = (ns + 1) & 0x7f;	// FIXME: hack!
+		};
+
+		break;
+	case LAPD_CMD_UI:
+		break;
+	case LAPD_CMD_SABME:
+		sap->vs = 0;
+		sap->vr = 0;
+		sap->va = 0;
+
+		// ua
+		resp[l++] = data[0];
+		resp[l++] = (tei << 1) | 1;
+		resp[l++] = 0x73;
+		li->transmit_cb(resp, l, li->cbdata);
+		if (teip->state != LAPD_TEI_ACTIVE) {
+			if (teip->state == LAPD_TEI_ASSIGNED) {
+				lapd_tei_set_state(teip,
+						   LAPD_TEI_ACTIVE);
+				//printf("ASSIGNED and ACTIVE\n");
+			} else {
+#if 0
+				DEBUGP(DMI, "rr in strange state, send rej\n");
+
+				// rej
+				resp[l++] = (sap-> sapi << 2) | (li->network_side ? 0 : 2);
+				resp[l++] = (tei << 1) | 1;
+				resp[l++] = 0x09;	//rej
+				resp[l++] = ((sap->vr + 1) << 1) | 0;
+				li->transmit_cb(resp, l, li->cbdata);
+				pf = 0;	// dont reply
+#endif
+			};
+		};
+
+		*prim = LAPD_MPH_ACTIVATE_IND;
+		break;
+	case LAPD_CMD_UA:
+		sap->vs = 0;
+		sap->vr = 0;
+		sap->va = 0;
+		lapd_tei_set_state(teip, LAPD_TEI_ACTIVE);
+		lapd_sap_set_state(teip, sapi, SAP_STATE_ACTIVE);
+		*prim = LAPD_MPH_ACTIVATE_IND;
+		break;
+	case LAPD_CMD_RR:
+		sap->va = (nr & 0x7f);
+#if 0
+		if (teip->state != LAPD_TEI_ACTIVE) {
+			if (teip->state == LAPD_TEI_ASSIGNED) {
+				lapd_tei_set_state(teip, LAPD_TEI_ACTIVE);
+				*prim = LAPD_MPH_ACTIVATE_IND;
+				//printf("ASSIGNED and ACTIVE\n");
+			} else {
+#if 0
+				DEBUGP(DMI, "rr in strange " "state, send rej\n");
+
+				// rej
+				resp[l++] = (sap-> sapi << 2) | (li->network_side ? 0 : 2);
+				resp[l++] = (tei << 1) | 1;
+				resp[l++] = 0x09;	//rej
+				resp[l++] =
+				    ((sap->vr + 1) << 1) | 0;
+				li->transmit_cb(resp, l, li->cbdata);
+				pf = 0;	// dont reply
+#endif
+			};
+		};
+#endif
+		if (pf) {
+			// interrogating us, send rr
+			resp[l++] = data[0];
+			resp[l++] = (tei << 1) | 1;
+			resp[l++] = 0x01;	// rr
+			resp[l++] = (LAPD_NR(sap) << 1) | (data[3] & 1);	// pf bit from req
+
+			li->transmit_cb(resp, l, li->cbdata);
+
+		};
+		break;
+	case LAPD_CMD_FRMR:
+		// frame reject
+#if 0
+		if (teip->state == LAPD_TEI_ACTIVE)
+			*prim = LAPD_MPH_DEACTIVATE_IND;
+		lapd_tei_set_state(teip, LAPD_TEI_ASSIGNED);
+#endif
+		LOGP(DMI, LOGL_NOTICE, "frame reject, ignoring\n");
+		break;
+	case LAPD_CMD_DISC:
+		// disconnect
+		resp[l++] = data[0];
+		resp[l++] = (tei << 1) | 1;
+		resp[l++] = 0x73;
+		li->transmit_cb(resp, l, li->cbdata);
+		lapd_tei_set_state(teip, LAPD_TEI_NONE);
+		break;
+	default:
+		LOGP(DMI, LOGL_NOTICE, "unknown cmd for tei %d (cmd %x)\n",
+		     tei, cmd);
+		break;
+	}
+
+	if (typ == LAPD_TYPE_I) {
+		/* send rr
+		 * Thu Jan 22 19:17:13 2009 <4000> sangoma.c:340 read  (62/25)   4: fa 33 01 0a 
+		 * lapd <- S RR sapi 3e tei  25 cmd 0 pf 0 ns  -1 nr   5 ilen 0 teip 0x613800 vs 7 va 5 vr 2 len 4
+		 */
+
+		/* interrogating us, send rr */
+		DEBUGP(DMI, "Sending RR response\n");
+		resp[l++] = data[0];
+		resp[l++] = (tei << 1) | 1;
+		resp[l++] = 0x01;	// rr
+		resp[l++] = (LAPD_NR(sap) << 1) | (data[3] & 1);	// pf bit from req
+
+		li->transmit_cb(resp, l, li->cbdata);
+
+		if (cmd != 0) {
+			*prim = LAPD_DL_DATA_IND;
+			return contents;
+		}
+	} else if (tei != 127 && typ == LAPD_TYPE_U && cmd == LAPD_CMD_UI) {
+		*prim = LAPD_DL_UNITDATA_IND;
+		return contents;
+	}
+
+	return NULL;
+};
+
+/* low-level function to send a single SABM message */
+static int lapd_send_sabm(struct lapd_instance *li, uint8_t tei, uint8_t sapi)
+{
+	struct msgb *msg = msgb_alloc_headroom(1024, 128, "LAPD SABM");
+	if (!msg)
+		return -ENOMEM;
+
+	DEBUGP(DMI, "Sending SABM for TEI=%u, SAPI=%u\n", tei, sapi);
+
+	msgb_put_u8(msg, (sapi << 2) | (li->network_side ? 2 : 0));
+	msgb_put_u8(msg, (tei << 1) | 1);
+	msgb_put_u8(msg, 0x7F);
+
+	li->transmit_cb(msg->data, msg->len, li->cbdata);
+
+	msgb_free(msg);
+
+	return 0;
+}
+
+/* timer call-back function for SABM re-transmission */
+static void sabme_timer_cb(void *_sap)
+{
+	struct lapd_sap *sap = _sap;
+
+	lapd_send_sabm(sap->tei->li, sap->tei->tei, sap->sapi);
+
+	if (sap->state == SAP_STATE_SABM_RETRANS)
+		osmo_timer_schedule(&sap->sabme_timer, SABM_INTERVAL);
+}
+
+/* Start a (user-side) SAP for the specified TEI/SAPI on the LAPD instance */
+int lapd_sap_start(struct lapd_instance *li, uint8_t tei, uint8_t sapi)
+{
+	struct lapd_sap *sap;
+	struct lapd_tei *teip;
+
+	teip = teip_from_tei(li, tei);
+	if (!teip)
+		teip = lapd_tei_alloc(li, tei);
+
+	sap = lapd_sap_find(teip, sapi);
+	if (sap)
+		return -EEXIST;
+
+	sap = lapd_sap_alloc(teip, sapi);
+
+	lapd_sap_set_state(teip, sapi, SAP_STATE_SABM_RETRANS);
+
+	return 0;
+}
+
+/* Stop a (user-side) SAP for the specified TEI/SAPI on the LAPD instance */
+int lapd_sap_stop(struct lapd_instance *li, uint8_t tei, uint8_t sapi)
+{
+	struct lapd_tei *teip;
+	struct lapd_sap *sap;
+
+	teip = teip_from_tei(li, tei);
+	if (!teip)
+		return -ENODEV;
+
+	sap = lapd_sap_find(teip, sapi);
+	if (!sap)
+		return -ENODEV;
+
+	lapd_sap_set_state(teip, sapi, SAP_STATE_INACTIVE);
+
+	llist_del(&sap->list);
+	talloc_free(sap);
+
+	return 0;
+}
+
+/* Transmit Data (I-Frame) on the given LAPD Instance / TEI / SAPI */
+void lapd_transmit(struct lapd_instance *li, uint8_t tei, uint8_t sapi,
+		   uint8_t *data, unsigned int len)
+{
+	struct lapd_tei *teip = teip_from_tei(li, tei);
+	struct lapd_sap *sap;
+
+	if (!teip) {
+		LOGP(DMI, LOGL_ERROR, "Cannot transmit on non-existing "
+		     "TEI %u\n", tei);
+		return;
+	}
+
+	sap = lapd_sap_find(teip, sapi);
+	if (!sap) {
+		LOGP(DMI, LOGL_INFO, "Tx on unknown SAPI=%u in TEI=%u, "
+			"allocating\n", sapi, tei);
+		sap = lapd_sap_alloc(teip, sapi);
+	}
+
+	/* prepend stuff */
+	uint8_t buf[10000];
+	memset(buf, 0, sizeof(buf));
+	memmove(buf + 4, data, len);
+	len += 4;
+
+	buf[0] = (sapi << 2) | (li->network_side ? 2 : 0);
+	buf[1] = (tei << 1) | 1;
+	buf[2] = (LAPD_NS(sap) << 1);
+	buf[3] = (LAPD_NR(sap) << 1) | 0;
+
+	sap->vs = (sap->vs + 1) & 0x7f;
+
+	li->transmit_cb(buf, len, li->cbdata);
+};
+
+/* Allocate a new LAPD instance */
+struct lapd_instance *lapd_instance_alloc(int network_side,
+					  void (*tx_cb)(uint8_t *data, int len,
+							void *cbdata), void *cbdata)
+{
+	struct lapd_instance *li;
+
+	li = talloc_zero(NULL, struct lapd_instance);
+	if (!li)
+		return NULL;
+
+	li->transmit_cb = tx_cb;
+	li->cbdata = cbdata;
+	li->network_side = network_side;
+	INIT_LLIST_HEAD(&li->tei_list);
+
+	return li;
+}
diff --git a/src/input/misdn.c b/src/input/misdn.c
new file mode 100644
index 0000000..45d5e06
--- /dev/null
+++ b/src/input/misdn.c
@@ -0,0 +1,547 @@
+/* OpenBSC Abis input driver for mISDNuser */
+
+/* (C) 2008-2009 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2009 by Holger Hans Peter Freyther <zecke@selfish.org>
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "internal.h"
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <time.h>
+#include <sys/fcntl.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <arpa/inet.h>
+#include <mISDNif.h>
+
+//#define AF_COMPATIBILITY_FUNC
+//#include <compat_af_isdn.h>
+#ifndef AF_ISDN
+#define AF_ISDN 34
+#define PF_ISDN AF_ISDN
+#endif
+
+#include <osmocom/core/select.h>
+#include <osmocom/core/msgb.h>
+#include <osmocom/core/logging.h>
+#include <osmocom/gsm/abis/e1_input.h>
+#include <talloc.h>
+/*#include <openbsc/debug.h>
+#include <openbsc/gsm_data.h>
+#include <openbsc/abis_nm.h>
+#include <openbsc/abis_rsl.h>
+#include <openbsc/subchan_demux.h>
+#include <openbsc/e1_input.h>
+#include <openbsc/signal.h> */
+
+#define TS1_ALLOC_SIZE	300
+
+struct prim_name {
+	unsigned int prim;
+	const char *name;
+};
+
+const struct prim_name prim_names[] = {
+	{ PH_CONTROL_IND, "PH_CONTROL_IND" },
+	{ PH_DATA_IND, "PH_DATA_IND" },
+	{ PH_DATA_CNF, "PH_DATA_CNF" },
+	{ PH_ACTIVATE_IND, "PH_ACTIVATE_IND" },
+	{ DL_ESTABLISH_IND, "DL_ESTABLISH_IND" },
+	{ DL_ESTABLISH_CNF, "DL_ESTABLISH_CNF" },
+	{ DL_RELEASE_IND, "DL_RELEASE_IND" },
+	{ DL_RELEASE_CNF, "DL_RELEASE_CNF" },
+	{ DL_DATA_IND, "DL_DATA_IND" },
+	{ DL_UNITDATA_IND, "DL_UNITDATA_IND" },
+	{ DL_INFORMATION_IND, "DL_INFORMATION_IND" },
+	{ MPH_ACTIVATE_IND, "MPH_ACTIVATE_IND" },
+	{ MPH_DEACTIVATE_IND, "MPH_DEACTIVATE_IND" },
+};
+
+const char *get_prim_name(unsigned int prim)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(prim_names); i++) {
+		if (prim_names[i].prim == prim)
+			return prim_names[i].name;
+	}
+
+	return "UNKNOWN";
+}
+
+static int handle_ts1_read(struct osmo_fd *bfd)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+	struct e1inp_sign_link *link;
+	struct msgb *msg = msgb_alloc(TS1_ALLOC_SIZE, "mISDN TS1");
+	struct sockaddr_mISDN l2addr;
+	struct mISDNhead *hh;
+	socklen_t alen;
+	int ret;
+
+	if (!msg)
+		return -ENOMEM;
+
+	hh = (struct mISDNhead *) msg->data;
+
+	alen = sizeof(l2addr);
+	ret = recvfrom(bfd->fd, msg->data, 300, 0,
+		       (struct sockaddr *) &l2addr, &alen);
+	if (ret < 0) {
+		fprintf(stderr, "recvfrom error  %s\n", strerror(errno));
+		return ret;
+	}
+
+	if (alen != sizeof(l2addr)) {
+		fprintf(stderr, "%s error len\n", __func__);
+		return -EINVAL;
+	}
+
+	msgb_put(msg, ret);
+
+	DEBUGP(DMI, "alen =%d, dev(%d) channel(%d) sapi(%d) tei(%d)\n",
+		alen, l2addr.dev, l2addr.channel, l2addr.sapi, l2addr.tei);
+
+	DEBUGP(DMI, "<= len = %d, prim(0x%x) id(0x%x): %s\n",
+		ret, hh->prim, hh->id, get_prim_name(hh->prim));
+
+	switch (hh->prim) {
+	case DL_INFORMATION_IND:
+		/* mISDN tells us which channel number is allocated for this
+		 * tuple of (SAPI, TEI). */
+		DEBUGP(DMI, "DL_INFORMATION_IND: use channel(%d) sapi(%d) tei(%d) for now\n",
+			l2addr.channel, l2addr.sapi, l2addr.tei);
+		link = e1inp_lookup_sign_link(e1i_ts, l2addr.tei, l2addr.sapi);
+		if (!link) {
+			DEBUGPC(DMI, "mISDN message for unknown sign_link\n");
+			msgb_free(msg);
+			return -EINVAL;
+		}
+		/* save the channel number in the driver private struct */
+		link->driver.misdn.channel = l2addr.channel;
+		break;
+	case DL_ESTABLISH_IND:
+		DEBUGP(DMI, "DL_ESTABLISH_IND: channel(%d) sapi(%d) tei(%d)\n",
+			l2addr.channel, l2addr.sapi, l2addr.tei);
+		/* For some strange reason, sometimes the DL_INFORMATION_IND tells
+		 * us the wrong channel, and we only get the real channel number
+		 * during the DL_ESTABLISH_IND */
+		link = e1inp_lookup_sign_link(e1i_ts, l2addr.tei, l2addr.sapi);
+		if (!link) {
+			DEBUGPC(DMI, "mISDN message for unknown sign_link\n");
+			msgb_free(msg);
+			return -EINVAL;
+		}
+		/* save the channel number in the driver private struct */
+		link->driver.misdn.channel = l2addr.channel;
+		ret = e1inp_event(e1i_ts, S_INP_TEI_UP, l2addr.tei, l2addr.sapi);
+		break;
+	case DL_RELEASE_IND:
+		DEBUGP(DMI, "DL_RELEASE_IND: channel(%d) sapi(%d) tei(%d)\n",
+		l2addr.channel, l2addr.sapi, l2addr.tei);
+		ret = e1inp_event(e1i_ts, S_INP_TEI_DN, l2addr.tei, l2addr.sapi);
+		break;
+	case DL_DATA_IND:
+	case DL_UNITDATA_IND:
+		msg->l2h = msg->data + MISDN_HEADER_LEN;
+		DEBUGP(DMI, "RX: %s\n", osmo_hexdump(msgb_l2(msg), ret - MISDN_HEADER_LEN));
+		ret = e1inp_rx_ts(e1i_ts, msg, l2addr.tei, l2addr.sapi);
+		break;
+	case PH_ACTIVATE_IND:
+		DEBUGP(DMI, "PH_ACTIVATE_IND: channel(%d) sapi(%d) tei(%d)\n",
+		l2addr.channel, l2addr.sapi, l2addr.tei);
+		break;
+	case PH_DEACTIVATE_IND:
+		DEBUGP(DMI, "PH_DEACTIVATE_IND: channel(%d) sapi(%d) tei(%d)\n",
+		l2addr.channel, l2addr.sapi, l2addr.tei);
+		break;
+	default:
+		break;
+	}
+	return ret;
+}
+
+static int ts_want_write(struct e1inp_ts *e1i_ts)
+{
+	/* We never include the mISDN B-Channel FD into the
+	 * writeset, since it doesn't support poll() based
+	 * write flow control */		
+	if (e1i_ts->type == E1INP_TS_TYPE_TRAU)
+		return 0;
+
+	e1i_ts->driver.misdn.fd.when |= BSC_FD_WRITE;
+
+	return 0;
+}
+
+static void timeout_ts1_write(void *data)
+{
+	struct e1inp_ts *e1i_ts = (struct e1inp_ts *)data;
+
+	/* trigger write of ts1, due to tx delay timer */
+	ts_want_write(e1i_ts);
+}
+
+static int handle_ts1_write(struct osmo_fd *bfd)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+	struct e1inp_sign_link *sign_link;
+	struct sockaddr_mISDN sa;
+	struct msgb *msg;
+	struct mISDNhead *hh;
+	uint8_t *l2_data;
+	int ret;
+
+	bfd->when &= ~BSC_FD_WRITE;
+
+	/* get the next msg for this timeslot */
+	msg = e1inp_tx_ts(e1i_ts, &sign_link);
+	if (!msg) {
+		/* no message after tx delay timer */
+		return 0;
+	}
+
+	l2_data = msg->data;
+
+	/* prepend the mISDNhead */
+	hh = (struct mISDNhead *) msgb_push(msg, sizeof(*hh));
+	hh->prim = DL_DATA_REQ;
+
+	DEBUGP(DMI, "TX channel(%d) TEI(%d) SAPI(%d): %s\n",
+		sign_link->driver.misdn.channel, sign_link->tei,
+		sign_link->sapi, osmo_hexdump(l2_data, msg->len - MISDN_HEADER_LEN));
+
+	/* construct the sockaddr */
+	sa.family = AF_ISDN;
+	sa.sapi = sign_link->sapi;
+	sa.dev = sign_link->tei;
+	sa.channel = sign_link->driver.misdn.channel;
+
+	ret = sendto(bfd->fd, msg->data, msg->len, 0,
+		     (struct sockaddr *)&sa, sizeof(sa));
+	if (ret < 0)
+		fprintf(stderr, "%s sendto failed %d\n", __func__, ret);
+	msgb_free(msg);
+
+	/* set tx delay timer for next event */
+	e1i_ts->sign.tx_timer.cb = timeout_ts1_write;
+	e1i_ts->sign.tx_timer.data = e1i_ts;
+	osmo_timer_schedule(&e1i_ts->sign.tx_timer, 0, e1i_ts->sign.delay);
+
+	return ret;
+}
+
+#define BCHAN_TX_GRAN	160
+/* write to a B channel TS */
+static int handle_tsX_write(struct osmo_fd *bfd)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+	struct mISDNhead *hh;
+	uint8_t tx_buf[BCHAN_TX_GRAN + sizeof(*hh)];
+	struct subch_mux *mx = &e1i_ts->trau.mux;
+	int ret;
+
+	hh = (struct mISDNhead *) tx_buf;
+	hh->prim = PH_DATA_REQ;
+
+	subchan_mux_out(mx, tx_buf+sizeof(*hh), BCHAN_TX_GRAN);
+
+	DEBUGP(DMIB, "BCHAN TX: %s\n",
+		osmo_hexdump(tx_buf+sizeof(*hh), BCHAN_TX_GRAN));
+
+	ret = send(bfd->fd, tx_buf, sizeof(*hh) + BCHAN_TX_GRAN, 0);
+	if (ret < sizeof(*hh) + BCHAN_TX_GRAN)
+		DEBUGP(DMIB, "send returns %d instead of %zu\n", ret,
+			sizeof(*hh) + BCHAN_TX_GRAN);
+
+	return ret;
+}
+
+#define TSX_ALLOC_SIZE 4096
+/* FIXME: read from a B channel TS */
+static int handle_tsX_read(struct osmo_fd *bfd)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+	struct msgb *msg = msgb_alloc(TSX_ALLOC_SIZE, "mISDN TSx");
+	struct mISDNhead *hh;
+	int ret;
+
+	if (!msg)
+		return -ENOMEM;
+
+	hh = (struct mISDNhead *) msg->data;
+
+	ret = recv(bfd->fd, msg->data, TSX_ALLOC_SIZE, 0);
+	if (ret < 0) {
+		fprintf(stderr, "recvfrom error  %s\n", strerror(errno));
+		return ret;
+	}
+
+	msgb_put(msg, ret);
+
+	if (hh->prim != PH_CONTROL_IND)
+		DEBUGP(DMIB, "<= BCHAN len = %d, prim(0x%x) id(0x%x): %s\n",
+			ret, hh->prim, hh->id, get_prim_name(hh->prim));
+
+	switch (hh->prim) {
+	case PH_DATA_IND:
+		msg->l2h = msg->data + MISDN_HEADER_LEN;
+		DEBUGP(DMIB, "BCHAN RX: %s\n",
+			osmo_hexdump(msgb_l2(msg), ret - MISDN_HEADER_LEN));
+		ret = e1inp_rx_ts(e1i_ts, msg, 0, 0);
+		break;
+	case PH_ACTIVATE_IND:
+	case PH_DATA_CNF:
+		/* physical layer indicates that data has been sent,
+		 * we thus can send some more data */
+		ret = handle_tsX_write(bfd);
+	default:
+		break;
+	}
+	/* FIXME: why do we free signalling msgs in the caller, and trau not? */
+	msgb_free(msg);
+
+	return ret;
+}
+
+/* callback from select.c in case one of the fd's can be read/written */
+static int misdn_fd_cb(struct osmo_fd *bfd, unsigned int what)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	unsigned int idx = ts_nr-1;
+	struct e1inp_ts *e1i_ts = &line->ts[idx];
+	int rc = 0;
+
+	switch (e1i_ts->type) {
+	case E1INP_TS_TYPE_SIGN:
+		if (what & BSC_FD_READ)
+			rc = handle_ts1_read(bfd);
+		if (what & BSC_FD_WRITE)
+			rc = handle_ts1_write(bfd);
+		break;
+	case E1INP_TS_TYPE_TRAU:
+		if (what & BSC_FD_READ)
+			rc = handle_tsX_read(bfd);
+		/* We never include the mISDN B-Channel FD into the
+		 * writeset, since it doesn't support poll() based
+		 * write flow control */		
+		break;
+	default:
+		fprintf(stderr, "unknown E1 TS type %u\n", e1i_ts->type);
+		break;
+	}
+
+	return rc;
+}
+
+static int activate_bchan(struct e1inp_line *line, int ts, int act)
+{
+	struct mISDNhead hh;
+	int ret;
+	unsigned int idx = ts-1;
+	struct e1inp_ts *e1i_ts = &line->ts[idx];
+	struct osmo_fd *bfd = &e1i_ts->driver.misdn.fd;
+
+	fprintf(stdout, "activate bchan\n");
+	if (act)
+		hh.prim = PH_ACTIVATE_REQ;
+	else
+		hh.prim = PH_DEACTIVATE_REQ;
+
+	hh.id = MISDN_ID_ANY;
+	ret = sendto(bfd->fd, &hh, sizeof(hh), 0, NULL, 0);
+	if (ret < 0) {
+		fprintf(stdout, "could not send ACTIVATE_RQ %s\n",
+			strerror(errno));
+	}
+
+	return ret;
+}
+
+static int
+mi_e1_line_update(struct e1inp_line *line, enum e1inp_line_role role);
+
+struct e1inp_driver misdn_driver = {
+	.name = "misdn",
+	.want_write = ts_want_write,
+	.default_delay = 50000,
+	.line_update = &mi_e1_line_update,
+};
+
+static int mi_e1_setup(struct e1inp_line *line, int release_l2)
+{
+	int ts, ret;
+
+	/* TS0 is CRC4, don't need any fd for it */
+	for (ts = 1; ts < NUM_E1_TS; ts++) {
+		unsigned int idx = ts-1;
+		struct e1inp_ts *e1i_ts = &line->ts[idx];
+		struct osmo_fd *bfd = &e1i_ts->driver.misdn.fd;
+		struct sockaddr_mISDN addr;
+
+		bfd->data = line;
+		bfd->priv_nr = ts;
+		bfd->cb = misdn_fd_cb;
+
+		switch (e1i_ts->type) {
+		case E1INP_TS_TYPE_NONE:
+			continue;
+			break;
+		case E1INP_TS_TYPE_SIGN:
+			bfd->fd = socket(PF_ISDN, SOCK_DGRAM, ISDN_P_LAPD_NT);
+			bfd->when = BSC_FD_READ;
+			break;
+		case E1INP_TS_TYPE_TRAU:
+			bfd->fd = socket(PF_ISDN, SOCK_DGRAM, ISDN_P_B_RAW);
+			/* We never include the mISDN B-Channel FD into the
+	 		* writeset, since it doesn't support poll() based
+	 		* write flow control */		
+			bfd->when = BSC_FD_READ;
+			break;
+		}
+
+		if (bfd->fd < 0) {
+			fprintf(stderr, "%s could not open socket %s\n",
+				__func__, strerror(errno));
+			return bfd->fd;
+		}
+
+		memset(&addr, 0, sizeof(addr));
+		addr.family = AF_ISDN;
+		addr.dev = line->num;
+		switch (e1i_ts->type) {
+		case E1INP_TS_TYPE_SIGN:
+			addr.channel = 0;
+			/* SAPI not supported yet in kernel */
+			//addr.sapi = e1inp_ts->sign.sapi;
+			addr.sapi = 0;
+			addr.tei = GROUP_TEI;
+			break;
+		case E1INP_TS_TYPE_TRAU:
+			addr.channel = ts;
+			break;
+		default:
+			DEBUGP(DMI, "unsupported E1 TS type: %u\n",
+				e1i_ts->type);
+			break;
+		}
+
+		ret = bind(bfd->fd, (struct sockaddr *) &addr, sizeof(addr));
+		if (ret < 0) {
+			fprintf(stderr, "could not bind l2 socket %s\n",
+				strerror(errno));
+			return -EIO;
+		}
+
+		if (e1i_ts->type == E1INP_TS_TYPE_SIGN) {
+			ret = ioctl(bfd->fd, IMCLEAR_L2, &release_l2);
+			if (ret < 0) {
+				fprintf(stderr, "could not send IOCTL IMCLEAN_L2 %s\n", strerror(errno));
+				return -EIO;
+			}
+		}
+
+		/* FIXME: only activate B-Channels once we start to
+		 * use them to conserve CPU power */
+		if (e1i_ts->type == E1INP_TS_TYPE_TRAU)
+			activate_bchan(line, ts, 1);
+
+		ret = osmo_fd_register(bfd);
+		if (ret < 0) {
+			fprintf(stderr, "could not register FD: %s\n",
+				strerror(ret));
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int
+mi_e1_line_update(struct e1inp_line *line, enum e1inp_line_role role)
+{
+	struct mISDN_devinfo devinfo;
+	int sk, ret, cnt;
+
+	if (line->driver != &misdn_driver)
+		return -EINVAL;
+
+	/* open the ISDN card device */
+	sk = socket(PF_ISDN, SOCK_RAW, ISDN_P_BASE);
+	if (sk < 0) {
+		fprintf(stderr, "%s could not open socket %s\n",
+			__func__, strerror(errno));
+		return sk;
+	}
+
+	ret = ioctl(sk, IMGETCOUNT, &cnt);
+	if (ret) {
+		fprintf(stderr, "%s error getting interf count: %s\n",
+			__func__, strerror(errno));
+		close(sk);
+		return -ENODEV;
+	}
+	//DEBUGP(DMI,"%d device%s found\n", cnt, (cnt==1)?"":"s");
+	printf("%d device%s found\n", cnt, (cnt==1)?"":"s");
+#if 1
+	devinfo.id = line->num;
+	ret = ioctl(sk, IMGETDEVINFO, &devinfo);
+	if (ret < 0) {
+		fprintf(stdout, "error getting info for device %d: %s\n",
+			line->num, strerror(errno));
+		return -ENODEV;
+	}
+	fprintf(stdout, "        id:             %d\n", devinfo.id);
+	fprintf(stdout, "        Dprotocols:     %08x\n", devinfo.Dprotocols);
+	fprintf(stdout, "        Bprotocols:     %08x\n", devinfo.Bprotocols);
+	fprintf(stdout, "        protocol:       %d\n", devinfo.protocol);
+	fprintf(stdout, "        nrbchan:        %d\n", devinfo.nrbchan);
+	fprintf(stdout, "        name:           %s\n", devinfo.name);
+#endif
+
+	if (!(devinfo.Dprotocols & (1 << ISDN_P_NT_E1))) {
+		fprintf(stderr, "error: card is not of type E1 (NT-mode)\n");
+		return -EINVAL;
+	}
+
+	ret = mi_e1_setup(line, 1);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+void e1inp_misdn_init(void)
+{
+	/* register the driver with the core */
+	e1inp_driver_register(&misdn_driver);
+}