lapdm: Create a simple test case to transmit data between both ends

This is testing the establishment of two ends (BTS, MS) one is in
the polling mode as used by osmo-bts. Transfer data between the two
ends. The sent data is not verified though. This should be followed
up soon.

3 files changed, 283 insertions, 0 deletions

diff --git a/tests/lapd/Makefile.am b/tests/lapd/Makefile.am
new file mode 100644
index 00000000..f7e2ab0e
--- /dev/null
+++ b/tests/lapd/Makefile.am
@@ -0,0 +1,9 @@
+INCLUDES = $(all_includes) -I$(top_srcdir)/include
+AM_FLAGS = -Wall -O0
+noinst_PROGRAMS = lapd_test
+EXTRA_DIST = lapd_test.ok
+
+lapd_test_SOURCES = lapd_test.c
+lapd_test_LDADD = \
+	$(top_builddir)/src/libosmocore.la \
+	$(top_builddir)/src/gsm/libosmogsm.la
diff --git a/tests/lapd/lapd_test.c b/tests/lapd/lapd_test.c
new file mode 100644
index 00000000..e6b10b64
--- /dev/null
+++ b/tests/lapd/lapd_test.c
@@ -0,0 +1,258 @@
+/*
+ * (C) 2011 by Holger Hans Peter Freyther
+ * (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 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 <osmocom/core/logging.h>
+#include <osmocom/gsm/lapdm.h>
+#include <osmocom/gsm/rsl.h>
+
+#include <errno.h>
+
+#include <string.h>
+
+#define CHECK_RC(rc)	\
+	if (rc != 0) {	\
+		printf("Operation failed rc=%d on %s:%d\n", rc, __FILE__, __LINE__); \
+		abort(); \
+	}
+
+#define ASSERT(exp)    \
+	if (!(exp)) { \
+		printf("Assert failed %s %s:%d\n", #exp, __FILE__, __LINE__); \
+		abort(); \
+	}
+
+
+static struct log_info info = {};
+
+struct lapdm_polling_state {
+	struct lapdm_channel *bts;
+	int bts_read;
+
+	struct lapdm_channel *ms;
+	int ms_read;
+};
+
+static struct msgb *msgb_from_array(const uint8_t *data, int len)
+{
+	struct msgb *msg = msgb_alloc_headroom(4096, 128, "data");
+	msg->l3h = msgb_put(msg, len);
+	memcpy(msg->l3h, data, len);
+	return msg;
+}
+
+
+static struct msgb *create_cm_serv_req(void)
+{
+	struct msgb *msg;
+	static const uint8_t cm[] = {
+		0x05, 0x24, 0x31, 0x03, 0x50, 0x18, 0x93, 0x08,
+		0x29, 0x47, 0x80, 0x00, 0x00, 0x00, 0x00, 0x80,
+	};
+
+	msg = msgb_from_array(cm, sizeof(cm));
+	rsl_rll_push_l3(msg, RSL_MT_EST_REQ, 0, 0, 1);
+	return msg;
+}
+
+static struct msgb *create_mm_id_req(void)
+{
+	struct msgb *msg;
+	/* okay... not an identity request */
+	static const uint8_t mm[] = {
+		0x05, 0x24, 0x31, 0x03, 0x50, 0x18, 0x93, 0x08,
+		0x29, 0x47, 0x80, 0x00,
+	};
+
+	msg = msgb_from_array(mm, sizeof(mm));
+	rsl_rll_push_l3(msg, RSL_MT_DATA_REQ, 0, 0, 1);
+	return msg;
+}
+
+static struct msgb *create_dummy_data_req(void)
+{
+	struct msgb *msg;
+	/* okay... not an identity request */
+	static const uint8_t dummy1[] = {
+		0xab, 0x03, 0x30, 0x60, 0x06,
+	};
+
+	msg = msgb_from_array(dummy1, sizeof(dummy1));
+	rsl_rll_push_l3(msg, RSL_MT_DATA_REQ, 0, 0, 1);
+	return msg;
+}
+
+static int send(struct msgb *in_msg, struct lapdm_channel *chan)
+{
+	struct osmo_phsap_prim pp;
+	struct msgb *msg;
+	int rc;
+
+	msg = msgb_alloc_headroom(128, 64, "PH-DATA.ind");
+	osmo_prim_init(&pp.oph, SAP_GSM_PH, PRIM_PH_DATA,
+			PRIM_OP_INDICATION, msg);
+	/* copy over actual MAC block */
+	msg->l2h = msgb_put(msg, msgb_l2len(in_msg));
+	memcpy(msg->l2h, in_msg->l2h, msgb_l2len(in_msg));
+
+	/* LAPDm requires those... */
+	pp.u.data.chan_nr = 0;
+	pp.u.data.link_id = 0;
+        /* feed into the LAPDm code of libosmogsm */
+        rc = lapdm_phsap_up(&pp.oph, &chan->lapdm_dcch);
+	ASSERT(rc == 0 || rc == -EBUSY);
+	return 0;
+}
+
+/*
+ * I get called from the LAPDm code when something was sent my way...
+ */
+static int bts_to_ms_tx_cb(struct msgb *in_msg, struct lapdm_entity *le, void *_ctx)
+{
+	struct lapdm_polling_state *state = _ctx;
+
+	state->bts_read += 1;
+
+	printf("%s: MS->BTS(us) message %d\n", __func__, msgb_length(in_msg));
+	msgb_free(in_msg);
+
+	return 0;
+}
+
+static int ms_to_bts_l1_cb(struct osmo_prim_hdr *oph, void *_ctx)
+{
+	int rc;
+	struct lapdm_polling_state *state = _ctx;
+	printf("%s: MS(us) -> BTS prim message\n", __func__);
+
+	/* i stuff it into the LAPDm channel of the BTS */
+	rc = send(oph->msg, state->bts);
+	msgb_free(oph->msg);
+}
+
+static int ms_to_bts_tx_cb(struct msgb *msg, struct lapdm_entity *le, void *_ctx)
+{
+	struct lapdm_polling_state *state = _ctx;
+
+	printf("%s: BTS->MS(us) message %d\n", __func__, msgb_length(msg));
+
+	if (state->ms_read == 0) {
+		/* TODO: Verify that this is a: PRIM_DL_EST, PRIM_OP_CONFIRM */
+	} else if (state->ms_read == 1) {
+		/* TODO: Verify that this is: create_mm_id_req() */
+	}
+
+	state->ms_read += 1;
+	msgb_free(msg);
+	return 0;
+}
+
+static void test_lapdm_polling()
+{
+	printf("I do some very simple LAPDm test.\n");
+
+	int rc;
+	struct lapdm_polling_state test_state;
+	struct osmo_phsap_prim pp;
+
+	/* Configure LAPDm on both sides */
+	struct lapdm_channel bts_to_ms_channel;
+	struct lapdm_channel ms_to_bts_channel;
+	memset(&bts_to_ms_channel, 0, sizeof(bts_to_ms_channel));
+	memset(&ms_to_bts_channel, 0, sizeof(ms_to_bts_channel));
+
+	memset(&test_state, 0, sizeof(test_state));
+	test_state.bts = &bts_to_ms_channel;
+	test_state.ms = &ms_to_bts_channel;
+
+	/* BTS to MS in polling mode */
+	lapdm_channel_init(&bts_to_ms_channel, LAPDM_MODE_BTS);
+        lapdm_channel_set_flags(&bts_to_ms_channel, LAPDM_ENT_F_POLLING_ONLY);
+        lapdm_channel_set_l1(&bts_to_ms_channel, NULL, &test_state);
+        lapdm_channel_set_l3(&bts_to_ms_channel, bts_to_ms_tx_cb, &test_state);
+
+	/* MS to BTS in direct mode */
+	lapdm_channel_init(&ms_to_bts_channel, LAPDM_MODE_MS);
+	lapdm_channel_set_l1(&ms_to_bts_channel, ms_to_bts_l1_cb, &test_state);
+	lapdm_channel_set_l3(&ms_to_bts_channel, ms_to_bts_tx_cb, &test_state);
+
+	/*
+	 * We try to send messages from the MS to the BTS to the MS..
+	 */
+	/* 1. Start with MS -> BTS, BTS should have a pending message */
+	printf("Establishing link.\n");
+	lapdm_rslms_recvmsg(create_cm_serv_req(), &ms_to_bts_channel);
+
+	/* 2. Poll on the BTS for sending out a confirmation */
+	printf("\nConfirming\n");
+	ASSERT(test_state.bts_read == 1)
+	rc = lapdm_phsap_dequeue_prim(&bts_to_ms_channel.lapdm_dcch, &pp);
+	CHECK_RC(rc);
+	ASSERT(pp.oph.msg->data == pp.oph.msg->l2h);
+	send(pp.oph.msg, &ms_to_bts_channel);
+	msgb_free(pp.oph.msg);
+	ASSERT(test_state.ms_read == 1);
+
+	/* 3. Send some data to the MS */
+	printf("\nSending back to MS\n");
+	lapdm_rslms_recvmsg(create_mm_id_req(), &bts_to_ms_channel);
+	rc = lapdm_phsap_dequeue_prim(&bts_to_ms_channel.lapdm_dcch, &pp);
+	CHECK_RC(rc);
+	send(pp.oph.msg, &ms_to_bts_channel);
+	msgb_free(pp.oph.msg);
+	ASSERT(test_state.ms_read == 2);
+
+	/* verify that there is nothing more to poll */
+	rc = lapdm_phsap_dequeue_prim(&bts_to_ms_channel.lapdm_dcch, &pp);
+	ASSERT(rc < 0);
+
+	/* 3. And back to the BTS */
+	printf("\nSending back to BTS\n");
+	ASSERT(test_state.ms_read == 2);
+	lapdm_rslms_recvmsg(create_dummy_data_req(), &ms_to_bts_channel);
+
+
+	/* 4. And back to the MS */
+	ASSERT(test_state.bts_read == 2)
+	ASSERT(test_state.ms_read == 2);
+	rc = lapdm_phsap_dequeue_prim(&bts_to_ms_channel.lapdm_dcch, &pp);
+	CHECK_RC(rc);
+	send(pp.oph.msg, &ms_to_bts_channel);
+	ASSERT(test_state.ms_read == 2);
+	msgb_free(pp.oph.msg);
+
+	/* verify that there is nothing more to poll */
+	rc = lapdm_phsap_dequeue_prim(&bts_to_ms_channel.lapdm_dcch, &pp);
+	ASSERT(rc < 0);
+
+	/* clean up */
+	lapdm_channel_exit(&bts_to_ms_channel);
+	lapdm_channel_exit(&ms_to_bts_channel);
+}
+
+int main(int argc, char **argv)
+{
+	osmo_init_logging(&info);
+
+	test_lapdm_polling();
+	printf("Success.\n");
+
+	return 0;
+}
diff --git a/tests/lapd/lapd_test.ok b/tests/lapd/lapd_test.ok
new file mode 100644
index 00000000..3214c690
--- /dev/null
+++ b/tests/lapd/lapd_test.ok
@@ -0,0 +1,16 @@
+I do some very simple LAPDm test.
+Establishing link.
+ms_to_bts_l1_cb: MS(us) -> BTS prim message
+bts_to_ms_tx_cb: MS->BTS(us) message 29
+
+Confirming
+ms_to_bts_tx_cb: BTS->MS(us) message 9
+
+Sending back to MS
+ms_to_bts_tx_cb: BTS->MS(us) message 21
+ms_to_bts_l1_cb: MS(us) -> BTS prim message
+
+Sending back to BTS
+ms_to_bts_l1_cb: MS(us) -> BTS prim message
+bts_to_ms_tx_cb: MS->BTS(us) message 14
+Success.