Merge branch 'zecke/jolly-lapdm-fixes'
* Squashed fix and testcase into one.
diff --git a/src/gsm/lapd_core.c b/src/gsm/lapd_core.c
index b33cf6e..f351308 100644
--- a/src/gsm/lapd_core.c
+++ b/src/gsm/lapd_core.c
@@ -820,7 +820,12 @@
"frame established state\n");
/* If link is lost on the remote side, we start over
* and send DL-ESTABLISH indication again. */
- if (dl->v_send != dl->v_recv) {
+ /* Additionally, continue in case of content resoltion
+ * (GSM network). This happens, if the mobile has not
+ * yet received UA or another mobile (collision) tries
+ * to establish connection. The mobile must receive
+ * UA again. */
+ if (!dl->cont_res && dl->v_send != dl->v_recv) {
LOGP(DLLAPD, LOGL_INFO, "Remote reestablish\n");
mdl_error(MDL_CAUSE_SABM_MF, lctx);
break;
@@ -831,7 +836,8 @@
#ifdef TEST_CONTENT_RESOLUTION_NETWORK
dl->cont_res->data[0] ^= 0x01;
#endif
- if (memcmp(dl->cont_res, msg->data, length)) {
+ if (memcmp(dl->cont_res->data, msg->data,
+ length)) {
LOGP(DLLAPD, LOGL_INFO, "Another SABM "
"with diffrent content - "
"ignoring!\n");
diff --git a/src/gsm/lapdm.c b/src/gsm/lapdm.c
index 2bda48a..71045aa 100644
--- a/src/gsm/lapdm.c
+++ b/src/gsm/lapdm.c
@@ -687,7 +687,8 @@
if (oph->sap != SAP_GSM_PH) {
LOGP(DLLAPD, LOGL_ERROR, "primitive for unknown SAP %u\n",
oph->sap);
- return -ENODEV;
+ rc = -ENODEV;
+ goto free;
}
switch (oph->primitive) {
@@ -695,7 +696,8 @@
if (oph->operation != PRIM_OP_INDICATION) {
LOGP(DLLAPD, LOGL_ERROR, "PH_DATA is not INDICATION %u\n",
oph->operation);
- return -ENODEV;
+ rc = -ENODEV;
+ goto free;
}
rc = l2_ph_data_ind(oph->msg, le, pp->u.data.chan_nr,
pp->u.data.link_id);
@@ -704,7 +706,8 @@
if (oph->operation != PRIM_OP_INDICATION) {
LOGP(DLLAPD, LOGL_ERROR, "PH_RTS is not INDICATION %u\n",
oph->operation);
- return -ENODEV;
+ rc = -ENODEV;
+ goto free;
}
rc = l2_ph_data_conf(oph->msg, le);
break;
@@ -718,12 +721,22 @@
rc = l2_ph_chan_conf(oph->msg, le, pp->u.rach_ind.fn);
break;
default:
- return -EIO;
+ rc = -EIO;
+ goto free;
}
break;
+ default:
+ LOGP(DLLAPD, LOGL_ERROR, "Unknown primitive %u\n",
+ oph->primitive);
+ rc = -EINVAL;
+ goto free;
}
return rc;
+
+free:
+ msgb_free(oph->msg);
+ return rc;
}
diff --git a/tests/lapd/lapd_test.c b/tests/lapd/lapd_test.c
index a60c45d..49b7eef 100644
--- a/tests/lapd/lapd_test.c
+++ b/tests/lapd/lapd_test.c
@@ -67,6 +67,12 @@
0x2b, 0x2b, 0x2b, 0x2b
};
+static const uint8_t ua[] = {
+ 0x01, 0x73, 0x41, 0x05, 0x24, 0x31, 0x03, 0x50,
+ 0x18, 0x93, 0x08, 0x29, 0x47, 0x80, 0x00, 0x00,
+ 0x00, 0x00, 0x80, 0x2b, 0x2b, 0x2b, 0x2b
+};
+
static const uint8_t mm[] = {
0x00, 0x0c, 0x00, 0x03, 0x01, 0x01, 0x20, 0x02,
0x00, 0x0b, 0x00, 0x03, 0x05, 0x04, 0x0d
@@ -153,6 +159,32 @@
return 0;
}
+static int send_sabm(struct lapdm_channel *chan, int second_ms)
+{
+ 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, 23);
+ msg->l2h[0] = 0x01;
+ msg->l2h[1] = 0x3f;
+ msg->l2h[2] = 0x01 | (sizeof(cm) << 2);
+ memcpy(msg->l2h + 3, cm_padded, sizeof(cm_padded));
+ msg->l2h[3] += second_ms; /* alter message, for second mobile */
+
+ /* 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);
+ OSMO_ASSERT(rc == 0 || rc == -EBUSY);
+ return 0;
+}
+
/*
* I get called from the LAPDm code when something was sent my way...
*/
@@ -348,12 +380,56 @@
lapdm_channel_exit(&bts_to_ms_channel);
}
+static void test_lapdm_contention_resolution()
+{
+ printf("I test contention resultion by having two mobiles collide and "
+ "first mobile repeating SABM.\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;
+ memset(&bts_to_ms_channel, 0, sizeof(bts_to_ms_channel));
+
+ memset(&test_state, 0, sizeof(test_state));
+ test_state.bts = &bts_to_ms_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);
+
+ /* Send SABM MS 1, we must get UA */
+ send_sabm(&bts_to_ms_channel, 0);
+ rc = lapdm_phsap_dequeue_prim(&bts_to_ms_channel.lapdm_dcch, &pp);
+ CHECK_RC(rc);
+ OSMO_ASSERT(memcmp(pp.oph.msg->l2h, ua, ARRAY_SIZE(ua)) == 0);
+
+ /* Send SABM MS 2, we must get nothing, due to collision */
+ send_sabm(&bts_to_ms_channel, 1);
+ rc = lapdm_phsap_dequeue_prim(&bts_to_ms_channel.lapdm_dcch, &pp);
+ OSMO_ASSERT(rc == -ENODEV);
+
+ /* Send SABM MS 1 again, we must get UA gain */
+ send_sabm(&bts_to_ms_channel, 0);
+ rc = lapdm_phsap_dequeue_prim(&bts_to_ms_channel.lapdm_dcch, &pp);
+ CHECK_RC(rc);
+ OSMO_ASSERT(memcmp(pp.oph.msg->l2h, ua, ARRAY_SIZE(ua)) == 0);
+
+ /* clean up */
+ lapdm_channel_exit(&bts_to_ms_channel);
+}
+
int main(int argc, char **argv)
{
osmo_init_logging(&info);
test_lapdm_polling();
test_lapdm_early_release();
+ test_lapdm_contention_resolution();
printf("Success.\n");
return 0;
diff --git a/tests/lapd/lapd_test.ok b/tests/lapd/lapd_test.ok
index f1b990e..aa92708 100644
--- a/tests/lapd/lapd_test.ok
+++ b/tests/lapd/lapd_test.ok
@@ -18,4 +18,7 @@
bts_to_ms_tx_cb: MS->BTS(us) message 14
BTS: Verifying dummy message.
I test RF channel release of an unestablished channel.
+I test contention resultion by having two mobiles collide and first mobile repeating SABM.
+bts_to_ms_tx_cb: MS->BTS(us) message 29
+BTS: Verifying CM request.
Success.