Added unix domain socket for sending and receiving SMS messages to/from external applications.

7 files changed, 311 insertions, 2 deletions

diff --git a/openbsc/include/openbsc/gsm_data.h b/openbsc/include/openbsc/gsm_data.h
index 874150535..04f3a1cc3 100644
--- a/openbsc/include/openbsc/gsm_data.h
+++ b/openbsc/include/openbsc/gsm_data.h
@@ -235,6 +235,9 @@ struct gsm_network {
 	struct mncc_sock_state *mncc_state;
 	int (*mncc_recv) (struct gsm_network *net, struct msgb *msg);
 	struct llist_head upqueue;
+	struct sms_sock_state *sms_state;
+	int (*sms_recv) (struct gsm_network *net, struct msgb *msg);
+	struct llist_head smsqueue;
 	struct llist_head trans_list;
 	struct bsc_api *bsc_api;
 
diff --git a/openbsc/include/openbsc/sms_sock.h b/openbsc/include/openbsc/sms_sock.h
new file mode 100644
index 000000000..a3c059703
--- /dev/null
+++ b/openbsc/include/openbsc/sms_sock.h
@@ -0,0 +1,34 @@
+/* (C) 2008-2009 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2008, 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/>.
+ *
+ */
+
+#ifndef _SMS_SOCK_H
+#define _SMS_SOCK_H
+
+#include <osmocom/core/linuxlist.h>
+#include <stdint.h>
+
+struct gsm_network;
+struct msgb;
+
+int sms_sock_try_deliver(struct gsm_network *net, struct msgb *msg);
+
+int sms_sock_init(struct gsm_network *net);
+
+#endif
diff --git a/openbsc/src/libcommon/gsm_data.c b/openbsc/src/libcommon/gsm_data.c
index 5f7e32e73..cedb13800 100644
--- a/openbsc/src/libcommon/gsm_data.c
+++ b/openbsc/src/libcommon/gsm_data.c
@@ -110,6 +110,7 @@ struct gsm_network *gsm_network_init(uint16_t country_code, uint16_t network_cod
 
 	INIT_LLIST_HEAD(&net->trans_list);
 	INIT_LLIST_HEAD(&net->upqueue);
+	INIT_LLIST_HEAD(&net->smsqueue);
 	INIT_LLIST_HEAD(&net->bts_list);
 
 	net->stats.chreq.total = osmo_counter_alloc("net.chreq.total");
diff --git a/openbsc/src/libmsc/Makefile.am b/openbsc/src/libmsc/Makefile.am
index 2b5059986..b053a0c2a 100644
--- a/openbsc/src/libmsc/Makefile.am
+++ b/openbsc/src/libmsc/Makefile.am
@@ -9,6 +9,7 @@ libmsc_a_SOURCES =	auth.c \
 			gsm_04_08.c gsm_04_11.c gsm_04_80.c \
 			gsm_subscriber.c \
 			mncc.c mncc_builtin.c mncc_sock.c \
+			sms_sock.c \
 			rrlp.c \
 			silent_call.c \
 			sms_queue.c \
diff --git a/openbsc/src/libmsc/gsm_04_11.c b/openbsc/src/libmsc/gsm_04_11.c
index e554b7401..698a34bc9 100644
--- a/openbsc/src/libmsc/gsm_04_11.c
+++ b/openbsc/src/libmsc/gsm_04_11.c
@@ -406,8 +406,15 @@ static int gsm340_rx_tpdu(struct gsm_subscriber_connection *conn, struct msgb *m
 			/* FIXME: handle the error somehow? */
 		}
 #else
-		rc = 1; /* cause 1: unknown subscriber */
-		osmo_counter_inc(conn->bts->network->stats.sms.no_receiver);
+		rc = sms_sock_try_deliver(conn->bts->network, msg);
+		if (rc == 1) {
+			rc = 1; /* cause 1: unknown subscriber */
+			osmo_counter_inc(conn->bts->network->stats.sms.no_receiver);
+		} else if (rc < 0) {
+			rc = 21; /* cause 21: short message transfer rejected */
+			/* FIXME: handle the error somehow? */
+		}
+
 #endif
 		goto out;
 	}
diff --git a/openbsc/src/libmsc/sms_sock.c b/openbsc/src/libmsc/sms_sock.c
new file mode 100644
index 000000000..8e42d7e3f
--- /dev/null
+++ b/openbsc/src/libmsc/sms_sock.c
@@ -0,0 +1,261 @@
+/* sms_sock.c: SMS interface to a unix domain socket */
+
+/* (C) 2008-2010 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2009 by Andreas Eversberg <Andreas.Eversberg@versatel.de>
+ * (C) 2012 by Holger Hans Peter Freyther
+ * 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 <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+
+#include <osmocom/core/talloc.h>
+#include <osmocom/core/select.h>
+#include <osmocom/gsm/protocol/gsm_04_08.h>
+
+#include <openbsc/debug.h>
+#include <openbsc/gsm_data.h>
+
+struct sms_sock_state {
+	struct gsm_network *net;
+	struct osmo_fd listen_bfd;	/* fd for listen socket */
+	struct osmo_fd conn_bfd;		/* fd for connection to lcr */
+};
+
+int sms_sock_try_deliver(struct gsm_network *net, struct msgb *msg)
+{
+	/* Check if we currently have a MNCC handler connected */
+	if (net->sms_state->conn_bfd.fd < 0) {
+		LOGP(DMNCC, LOGL_ERROR, "sms_sock receives for external CC app "
+			"but socket is gone\n");
+		/* free the original message */
+		msgb_free(msg);
+		return -1;
+	}
+
+	/* FIXME: check for some maximum queue depth? */
+
+	/* Actually enqueue the message and mark socket write need */
+	msgb_enqueue(&net->smsqueue, msg);
+	net->sms_state->conn_bfd.when |= BSC_FD_WRITE;
+	return 0;
+}
+
+static void sms_sock_close(struct sms_sock_state *state)
+{
+	struct osmo_fd *bfd = &state->conn_bfd;
+
+	LOGP(DMNCC, LOGL_NOTICE, "SMS Socket has LOST connection\n");
+
+	close(bfd->fd);
+	bfd->fd = -1;
+	osmo_fd_unregister(bfd);
+
+	/* re-enable the generation of ACCEPT for new connections */
+	state->listen_bfd.when |= BSC_FD_READ;
+
+	/* flush the queue */
+	while (!llist_empty(&state->net->smsqueue)) {
+		struct msgb *msg = msgb_dequeue(&state->net->smsqueue);
+		msgb_free(msg);
+	}
+}
+
+static int sms_sock_read(struct osmo_fd *bfd)
+{
+	struct sms_sock_state *state = (struct sms_sock_state *)bfd->data;
+	struct msgb *msg;
+	int rc;
+	
+	msg = msgb_alloc(256, "sms_sock_rx");
+	if (!msg)
+		return -ENOMEM;
+
+	rc = recv(bfd->fd, msg->tail, msgb_tailroom(msg), 0);
+	if (rc == 0)
+		goto close;
+
+	if (rc < 0) {
+		if (errno == EAGAIN)
+			return 0;
+		goto close;
+	}
+
+
+	// TODO: We should parse message here.
+	LOGP(DMNCC, LOGL_ERROR, "We should parse message here %s \n", osmo_hexdump(msg->tail, msgb_tailroom(msg)));
+	
+	msgb_free(msg);
+
+	return rc;
+
+close:
+	msgb_free(msg);
+	sms_sock_close(state);
+	return -1;
+}
+
+static int sms_sock_write(struct osmo_fd *bfd)
+{
+	struct sms_sock_state *state = bfd->data;
+	struct gsm_network *net = state->net;
+	int rc;
+
+	while (!llist_empty(&net->smsqueue)) {
+		struct msgb *msg, *msg2;
+
+		/* peek at the beginning of the queue */
+		msg = llist_entry(net->smsqueue.next, struct msgb, list);
+
+		bfd->when &= ~BSC_FD_WRITE;
+
+		/* bug hunter 8-): maybe someone forgot msgb_put(...) ? */
+		if (!msgb_length(msg)) {
+			LOGP(DMNCC, LOGL_ERROR, "message type with ZERO "
+				"bytes!\n");
+			goto dontsend;
+		}
+
+		/* try to send it over the socket */
+		rc = write(bfd->fd, msgb_sms(msg), (unsigned) (msg->tail - (uint8_t *)msgb_sms(msg)));
+		if (rc == 0)
+			goto close;
+		if (rc < 0) {
+			if (errno == EAGAIN) {
+				bfd->when |= BSC_FD_WRITE;
+				break;
+			}
+			goto close;
+		}
+
+dontsend:
+		/* _after_ we send it, we can deueue */
+		msg2 = msgb_dequeue(&net->smsqueue);
+		assert(msg == msg2);
+	}
+	return 0;
+
+close:
+	sms_sock_close(state);
+	return -1;
+}
+
+static int sms_sock_cb(struct osmo_fd *bfd, unsigned int flags)
+{
+	int rc = 0;
+
+	if (flags & BSC_FD_READ)
+		rc = sms_sock_read(bfd);
+	if (rc < 0)
+		return rc;
+
+	if (flags & BSC_FD_WRITE)
+		rc = sms_sock_write(bfd);
+
+	return rc;
+}
+
+/* accept a new connection */
+static int sms_sock_accept(struct osmo_fd *bfd, unsigned int flags)
+{
+	struct sms_sock_state *state = (struct sms_sock_state *)bfd->data;
+	struct osmo_fd *conn_bfd = &state->conn_bfd;
+	struct sockaddr_un un_addr;
+	socklen_t len;
+	int rc;
+
+	len = sizeof(un_addr);
+	rc = accept(bfd->fd, (struct sockaddr *) &un_addr, &len);
+	if (rc < 0) {
+		LOGP(DMNCC, LOGL_ERROR, "Failed to accept a new connection\n");
+		return -1;
+	}
+
+	if (conn_bfd->fd >= 0) {
+		LOGP(DMNCC, LOGL_NOTICE, "SMS app connects but we already have "
+			"another active connection ?!?\n");
+		/* We already have one SMS app connected, this is all we support */
+		state->listen_bfd.when &= ~BSC_FD_READ;
+		close(rc);
+		return 0;
+	}
+
+	conn_bfd->fd = rc;
+	conn_bfd->when = BSC_FD_READ;
+	conn_bfd->cb = sms_sock_cb;
+	conn_bfd->data = state;
+
+	if (osmo_fd_register(conn_bfd) != 0) {
+		LOGP(DMNCC, LOGL_ERROR, "Failed to register new connection fd\n");
+		close(conn_bfd->fd);
+		conn_bfd->fd = -1;
+		return -1;
+	}
+
+	LOGP(DMNCC, LOGL_NOTICE, "SMS Socket has connection with external "
+		"SMS application\n");
+
+	return 0;
+}
+
+
+int sms_sock_init(struct gsm_network *net)
+{
+	struct sms_sock_state *state;
+	struct osmo_fd *bfd;
+	int rc;
+
+	state = talloc_zero(tall_bsc_ctx, struct sms_sock_state);
+	if (!state)
+		return -ENOMEM;
+
+	state->net = net;
+	state->conn_bfd.fd = -1;
+
+	bfd = &state->listen_bfd;
+
+	rc = osmo_unixsock_listen(bfd, SOCK_STREAM, "/tmp/bsc_sms");
+	if (rc < 0) {
+		LOGP(DMNCC, LOGL_ERROR, "Could not create unix socket: %s\n",
+			strerror(errno));
+		talloc_free(state);
+		return rc;
+	}
+
+	bfd->when = BSC_FD_READ;
+	bfd->cb = sms_sock_accept;
+	bfd->data = state;
+
+	rc = osmo_fd_register(bfd);
+	if (rc < 0) {
+		LOGP(DMNCC, LOGL_ERROR, "Could not register listen fd: %d\n", rc);
+		close(bfd->fd);
+		talloc_free(state);
+		return rc;
+	}
+
+	net->sms_state = state;
+
+	return 0;
+}
diff --git a/openbsc/src/osmo-nitb/bsc_hack.c b/openbsc/src/osmo-nitb/bsc_hack.c
index 172fb8269..30c60239a 100644
--- a/openbsc/src/osmo-nitb/bsc_hack.c
+++ b/openbsc/src/osmo-nitb/bsc_hack.c
@@ -42,6 +42,7 @@
 #include <openbsc/vty.h>
 #include <openbsc/bss.h>
 #include <openbsc/mncc.h>
+#include <openbsc/sms_sock.h>
 #include <openbsc/token_auth.h>
 #include <openbsc/handover_decision.h>
 #include <openbsc/rrlp.h>
@@ -282,6 +283,7 @@ int main(int argc, char **argv)
 #ifdef BUILD_SMPP
 	smpp_openbsc_set_net(bsc_gsmnet);
 #endif
+	sms_sock_init(bsc_gsmnet);
 	bsc_api_init(bsc_gsmnet, msc_bsc_api());
 
 	bsc_gsmnet->ctrl = controlif_setup(bsc_gsmnet, 4249);