move openbsc/* to repos root

This is the first step in creating this repository from the legacy openbsc.git.

Like all other Osmocom repositories, keep the autoconf and automake files in
the repository root. openbsc.git has been the sole exception, which ends now.

Change-Id: I9c6f2a448d9cb1cc088cf1cf6918b69d7e69b4e7

1 files changed, 422 insertions, 0 deletions

diff --git a/src/libmsc/gsm_subscriber.c b/src/libmsc/gsm_subscriber.c
new file mode 100644
index 000000000..1a03cf76e
--- /dev/null
+++ b/src/libmsc/gsm_subscriber.c
@@ -0,0 +1,422 @@
+/* The concept of a subscriber for the MSC, roughly HLR/VLR functionality */
+
+/* (C) 2008 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2009,2013 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 <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include <time.h>
+#include <stdbool.h>
+
+#include <osmocom/core/talloc.h>
+
+#include <osmocom/vty/vty.h>
+
+#include <openbsc/gsm_subscriber.h>
+#include <openbsc/gsm_04_08.h>
+#include <openbsc/debug.h>
+#include <openbsc/paging.h>
+#include <openbsc/signal.h>
+#include <openbsc/db.h>
+#include <openbsc/chan_alloc.h>
+
+void *tall_sub_req_ctx;
+
+extern struct llist_head *subscr_bsc_active_subscribers(void);
+
+int gsm48_secure_channel(struct gsm_subscriber_connection *conn, int key_seq,
+                         gsm_cbfn *cb, void *cb_data);
+
+
+/*
+ * Struct for pending channel requests. This is managed in the
+ * llist_head requests of each subscriber. The reference counting
+ * should work in such a way that a subscriber with a pending request
+ * remains in memory.
+ */
+struct subscr_request {
+	struct llist_head entry;
+
+	/* the callback data */
+	gsm_cbfn *cbfn;
+	void *param;
+};
+
+static struct gsm_subscriber *get_subscriber(struct gsm_subscriber_group *sgrp,
+						int type, const char *ident)
+{
+	struct gsm_subscriber *subscr = db_get_subscriber(type, ident);
+	if (subscr)
+		subscr->group = sgrp;
+	return subscr;
+}
+
+/*
+ * We got the channel assigned and can now hand this channel
+ * over to one of our callbacks.
+ */
+static int subscr_paging_dispatch(unsigned int hooknum, unsigned int event,
+                                  struct msgb *msg, void *data, void *param)
+{
+	struct subscr_request *request, *tmp;
+	struct gsm_subscriber_connection *conn = data;
+	struct gsm_subscriber *subscr = param;
+	struct paging_signal_data sig_data;
+	struct bsc_subscr *bsub;
+	struct gsm_network *net;
+
+	OSMO_ASSERT(subscr && subscr->is_paging);
+	net = subscr->group->net;
+
+	/*
+	 * Stop paging on all other BTS. E.g. if this is
+	 * the first timeout on a BTS then the others will
+	 * timeout soon as well. Let's just stop everything
+	 * and forget we wanted to page.
+	 */
+
+	/* TODO MSC split -- creating a BSC subscriber directly from MSC data
+	 * structures in RAM. At some point the MSC will send a message to the
+	 * BSC instead. */
+	bsub = bsc_subscr_find_or_create_by_imsi(net->bsc_subscribers,
+						 subscr->imsi);
+	bsub->tmsi = subscr->tmsi;
+	bsub->lac = subscr->lac;
+	paging_request_stop(&net->bts_list, NULL, bsub, NULL, NULL);
+	bsc_subscr_put(bsub);
+
+	/* Inform parts of the system we don't know */
+	sig_data.subscr = subscr;
+	sig_data.bts	= conn ? conn->bts : NULL;
+	sig_data.conn	= conn;
+	sig_data.paging_result = event;
+	osmo_signal_dispatch(
+		SS_PAGING,
+		event == GSM_PAGING_SUCCEEDED ?
+			S_PAGING_SUCCEEDED : S_PAGING_EXPIRED,
+		&sig_data
+	);
+
+	llist_for_each_entry_safe(request, tmp, &subscr->requests, entry) {
+		llist_del(&request->entry);
+		request->cbfn(hooknum, event, msg, data, request->param);
+		talloc_free(request);
+	}
+
+	/* balanced with the moment we start paging */
+	subscr->is_paging = 0;
+	subscr_put(subscr);
+	return 0;
+}
+
+static int subscr_paging_sec_cb(unsigned int hooknum, unsigned int event,
+                                struct msgb *msg, void *data, void *param)
+{
+	int rc;
+
+	switch (event) {
+		case GSM_SECURITY_AUTH_FAILED:
+			/* Dispatch as paging failure */
+			rc = subscr_paging_dispatch(
+				GSM_HOOK_RR_PAGING, GSM_PAGING_EXPIRED,
+				msg, data, param);
+			break;
+
+		case GSM_SECURITY_NOAVAIL:
+		case GSM_SECURITY_SUCCEEDED:
+			/* Dispatch as paging failure */
+			rc = subscr_paging_dispatch(
+				GSM_HOOK_RR_PAGING, GSM_PAGING_SUCCEEDED,
+				msg, data, param);
+			break;
+
+		default:
+			rc = -EINVAL;
+	}
+
+	return rc;
+}
+
+static int subscr_paging_cb(unsigned int hooknum, unsigned int event,
+                            struct msgb *msg, void *data, void *param)
+{
+	struct gsm_subscriber_connection *conn = data;
+	struct gsm48_hdr *gh;
+	struct gsm48_pag_resp *pr;
+
+	/* Other cases mean problem, dispatch direclty */
+	if (event != GSM_PAGING_SUCCEEDED)
+		return subscr_paging_dispatch(hooknum, event, msg, data, param);
+
+	/* Get paging response */
+	gh = msgb_l3(msg);
+	pr = (struct gsm48_pag_resp *)gh->data;
+
+	/* We _really_ have a channel, secure it now ! */
+	return gsm48_secure_channel(conn, pr->key_seq, subscr_paging_sec_cb, param);
+}
+
+struct subscr_request *subscr_request_channel(struct gsm_subscriber *subscr,
+			int channel_type, gsm_cbfn *cbfn, void *param)
+{
+	int rc;
+	struct subscr_request *request;
+	struct bsc_subscr *bsub;
+	struct gsm_network *net = subscr->group->net;
+
+	/* Start paging.. we know it is async so we can do it before */
+	if (!subscr->is_paging) {
+		LOGP(DMM, LOGL_DEBUG, "Subscriber %s not paged yet.\n",
+			subscr_name(subscr));
+		/* TODO MSC split -- creating a BSC subscriber directly from
+		 * MSC data structures in RAM. At some point the MSC will send
+		 * a message to the BSC instead. */
+		bsub = bsc_subscr_find_or_create_by_imsi(net->bsc_subscribers,
+							 subscr->imsi);
+		bsub->tmsi = subscr->tmsi;
+		bsub->lac = subscr->lac;
+		rc = paging_request(net, bsub, channel_type, subscr_paging_cb,
+				    subscr);
+		bsc_subscr_put(bsub);
+		if (rc <= 0) {
+			LOGP(DMM, LOGL_ERROR, "Subscriber %s paging failed: %d\n",
+				subscr_name(subscr), rc);
+			return NULL;
+		}
+		/* reduced on the first paging callback */
+		subscr_get(subscr);
+		subscr->is_paging = 1;
+	}
+
+	/* TODO: Stop paging in case of memory allocation failure */
+	request = talloc_zero(subscr, struct subscr_request);
+	if (!request)
+		return NULL;
+
+	request->cbfn = cbfn;
+	request->param = param;
+	llist_add_tail(&request->entry, &subscr->requests);
+	return request;
+}
+
+void subscr_remove_request(struct subscr_request *request)
+{
+	llist_del(&request->entry);
+	talloc_free(request);
+}
+
+struct gsm_subscriber *subscr_create_subscriber(struct gsm_subscriber_group *sgrp,
+						const char *imsi)
+{
+	struct gsm_subscriber *subscr = db_create_subscriber(imsi,
+							     sgrp->net->ext_min,
+							     sgrp->net->ext_max,
+							     sgrp->net->auto_assign_exten);
+	if (subscr)
+		subscr->group = sgrp;
+	return subscr;
+}
+
+struct gsm_subscriber *subscr_get_by_tmsi(struct gsm_subscriber_group *sgrp,
+					  uint32_t tmsi)
+{
+	char tmsi_string[14];
+	struct gsm_subscriber *subscr;
+
+	/* we might have a record in memory already */
+	llist_for_each_entry(subscr, subscr_bsc_active_subscribers(), entry) {
+		if (tmsi == subscr->tmsi)
+			return subscr_get(subscr);
+	}
+
+	sprintf(tmsi_string, "%u", tmsi);
+	return get_subscriber(sgrp, GSM_SUBSCRIBER_TMSI, tmsi_string);
+}
+
+struct gsm_subscriber *subscr_get_by_imsi(struct gsm_subscriber_group *sgrp,
+					  const char *imsi)
+{
+	struct gsm_subscriber *subscr;
+
+	llist_for_each_entry(subscr, subscr_bsc_active_subscribers(), entry) {
+		if (strcmp(subscr->imsi, imsi) == 0)
+			return subscr_get(subscr);
+	}
+
+	return get_subscriber(sgrp, GSM_SUBSCRIBER_IMSI, imsi);
+}
+
+struct gsm_subscriber *subscr_get_by_extension(struct gsm_subscriber_group *sgrp,
+					       const char *ext)
+{
+	struct gsm_subscriber *subscr;
+
+	llist_for_each_entry(subscr, subscr_bsc_active_subscribers(), entry) {
+		if (strcmp(subscr->extension, ext) == 0)
+			return subscr_get(subscr);
+	}
+
+	return get_subscriber(sgrp, GSM_SUBSCRIBER_EXTENSION, ext);
+}
+
+struct gsm_subscriber *subscr_get_by_id(struct gsm_subscriber_group *sgrp,
+					unsigned long long id)
+{
+	struct gsm_subscriber *subscr;
+	char buf[32];
+	sprintf(buf, "%llu", id);
+
+	llist_for_each_entry(subscr, subscr_bsc_active_subscribers(), entry) {
+		if (subscr->id == id)
+			return subscr_get(subscr);
+	}
+
+	return get_subscriber(sgrp, GSM_SUBSCRIBER_ID, buf);
+}
+
+int subscr_update_expire_lu(struct gsm_subscriber *s, struct gsm_bts *bts)
+{
+	int rc;
+
+	if (!s) {
+		LOGP(DMM, LOGL_ERROR, "LU Expiration but NULL subscriber\n");
+		return -1;
+	}
+	if (!bts) {
+		LOGP(DMM, LOGL_ERROR, "%s: LU Expiration but NULL bts\n",
+		     subscr_name(s));
+		return -1;
+	}
+
+	/* Table 10.5.33: The T3212 timeout value field is coded as the
+	 * binary representation of the timeout value for
+	 * periodic updating in decihours. Mark the subscriber as
+	 * inactive if it missed two consecutive location updates.
+	 * Timeout is twice the t3212 value plus one minute */
+
+	/* Is expiration handling enabled? */
+	if (bts->si_common.chan_desc.t3212 == 0)
+		s->expire_lu = GSM_SUBSCRIBER_NO_EXPIRATION;
+	else
+		s->expire_lu = time(NULL) +
+			(bts->si_common.chan_desc.t3212 * 60 * 6 * 2) + 60;
+
+	rc = db_sync_subscriber(s);
+	db_subscriber_update(s);
+	return rc;
+}
+
+int subscr_update(struct gsm_subscriber *s, struct gsm_bts *bts, int reason)
+{
+	int rc;
+
+	/* FIXME: Migrate pending requests from one BSC to another */
+	switch (reason) {
+	case GSM_SUBSCRIBER_UPDATE_ATTACHED:
+		s->group = bts->network->subscr_group;
+		/* Indicate "attached to LAC" */
+		s->lac = bts->location_area_code;
+
+		LOGP(DMM, LOGL_INFO, "Subscriber %s ATTACHED LAC=%u\n",
+			subscr_name(s), s->lac);
+
+		/*
+		 * The below will set a new expire_lu but as a side-effect
+		 * the new lac will be saved in the database.
+		 */
+		rc = subscr_update_expire_lu(s, bts);
+		osmo_signal_dispatch(SS_SUBSCR, S_SUBSCR_ATTACHED, s);
+		break;
+	case GSM_SUBSCRIBER_UPDATE_DETACHED:
+		/* Only detach if we are currently in this area */
+		if (bts->location_area_code == s->lac)
+			s->lac = GSM_LAC_RESERVED_DETACHED;
+		LOGP(DMM, LOGL_INFO, "Subscriber %s DETACHED\n", subscr_name(s));
+		rc = db_sync_subscriber(s);
+		db_subscriber_update(s);
+		osmo_signal_dispatch(SS_SUBSCR, S_SUBSCR_DETACHED, s);
+		break;
+	default:
+		fprintf(stderr, "subscr_update with unknown reason: %d\n",
+			reason);
+		rc = db_sync_subscriber(s);
+		db_subscriber_update(s);
+		break;
+	};
+
+	return rc;
+}
+
+void subscr_update_from_db(struct gsm_subscriber *sub)
+{
+	db_subscriber_update(sub);
+}
+
+static void subscr_expire_callback(void *data, long long unsigned int id)
+{
+	struct gsm_network *net = data;
+	struct gsm_subscriber *s = subscr_get_by_id(net->subscr_group, id);
+	struct gsm_subscriber_connection *conn = connection_for_subscr(s);
+
+	/*
+	 * The subscriber is active and the phone stopped the timer. As
+	 * we don't want to periodically update the database for active
+	 * subscribers we will just do it when the subscriber was selected
+	 * for expiration. This way on the next around another subscriber
+	 * will be selected.
+	 */
+	if (conn && conn->expire_timer_stopped) {
+		LOGP(DMM, LOGL_DEBUG, "Not expiring subscriber %s (ID %llu)\n",
+			subscr_name(s), id);
+		subscr_update_expire_lu(s, conn->bts);
+		subscr_put(s);
+		return;
+	}
+
+
+	LOGP(DMM, LOGL_NOTICE, "Expiring inactive subscriber %s (ID %llu)\n",
+			subscr_name(s), id);
+	s->lac = GSM_LAC_RESERVED_DETACHED;
+	db_sync_subscriber(s);
+
+	subscr_put(s);
+}
+
+void subscr_expire(struct gsm_subscriber_group *sgrp)
+{
+	db_subscriber_expire(sgrp->net, subscr_expire_callback);
+}
+
+struct gsm_subscriber_connection *connection_for_subscr(struct gsm_subscriber *subscr)
+{
+	/* FIXME: replace this with a backpointer in gsm_subscriber? */
+	struct gsm_network *net = subscr->group->net;
+	struct gsm_subscriber_connection *conn;
+
+	llist_for_each_entry(conn, &net->subscr_conns, entry) {
+		if (conn->subscr == subscr)
+			return conn;
+	}
+
+	return NULL;
+}