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authorNeels Hofmeyr <neels@hofmeyr.de>2019-11-20 03:35:37 +0100
committerNeels Hofmeyr <neels@hofmeyr.de>2020-04-30 19:22:24 +0200
commitab7dc40f168da4326f207ef8aeeec40229c94486 (patch)
treece45f461c6dee3a93ee99eb98e5af7ca8cb2257c
parent86b507b6ea529f9cf861286d8e6fa3b5fde851d2 (diff)
D-GSM 1/n: add mslookup server in osmo-hlr
Implement the mslookup server to service remote mslookup requests. This patch merely adds the logic to answer incoming mslookup requests, an actual method to receive requests (mDNS) follows in a subsequent patch. - API to configure service names and addresses for the local site (per MSC). - determine whether a subscriber is on a local MSC (checking the local proxy will be added in subsequent patch that adds proxy capability). - VTY config follows in a subsequent patch. For a detailed overview of the D-GSM and mslookup related files, please see the elaborate comment at the top of mslookup.c (already added in an earlier patch). Change-Id: Ife4a61d71926d08f310a1aeed9d9f1974f64178b
-rw-r--r--include/osmocom/hlr/Makefile.am2
-rw-r--r--include/osmocom/hlr/hlr.h7
-rw-r--r--include/osmocom/hlr/mslookup_server.h65
-rw-r--r--include/osmocom/hlr/timestamp.h28
-rw-r--r--src/Makefile.am5
-rw-r--r--src/hlr.c1
-rw-r--r--src/mslookup_server.c376
-rw-r--r--src/timestamp.c53
8 files changed, 537 insertions, 0 deletions
diff --git a/include/osmocom/hlr/Makefile.am b/include/osmocom/hlr/Makefile.am
index 532fa5d..5c96ec8 100644
--- a/include/osmocom/hlr/Makefile.am
+++ b/include/osmocom/hlr/Makefile.am
@@ -10,5 +10,7 @@ noinst_HEADERS = \
hlr_vty_subscr.h \
logging.h \
lu_fsm.h \
+ mslookup_server.h \
rand.h \
+ timestamp.h \
$(NULL)
diff --git a/include/osmocom/hlr/hlr.h b/include/osmocom/hlr/hlr.h
index 5885600..1269994 100644
--- a/include/osmocom/hlr/hlr.h
+++ b/include/osmocom/hlr/hlr.h
@@ -67,6 +67,13 @@ struct hlr {
/* Bitmask of DB_SUBSCR_FLAG_* */
uint8_t subscr_create_on_demand_flags;
unsigned int subscr_create_on_demand_rand_msisdn_len;
+
+ struct {
+ struct {
+ uint32_t local_attach_max_age;
+ struct llist_head local_site_services;
+ } server;
+ } mslookup;
};
extern struct hlr *g_hlr;
diff --git a/include/osmocom/hlr/mslookup_server.h b/include/osmocom/hlr/mslookup_server.h
new file mode 100644
index 0000000..5425328
--- /dev/null
+++ b/include/osmocom/hlr/mslookup_server.h
@@ -0,0 +1,65 @@
+/* Copyright 2019 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ *
+ * 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/>.
+ *
+ */
+
+#pragma once
+
+struct osmo_mslookup_query;
+struct osmo_mslookup_result;
+
+/*! mslookup service name used for roaming/proxying between osmo-hlr instances. */
+#define OSMO_MSLOOKUP_SERVICE_HLR_GSUP "gsup.hlr"
+
+/*! What addresses to return to mslookup queries when a subscriber is attached at the local site.
+ * Mapping of service name to IP address and port. This corresponds to the VTY config for
+ * 'mslookup' / 'server' [/ 'msc MSC-1-2-3'] / 'service sip.voice at 1.2.3.4 1234'.
+ */
+struct mslookup_service_host {
+ struct llist_head entry;
+ char service[OSMO_MSLOOKUP_SERVICE_MAXLEN+1];
+ struct osmo_sockaddr_str host_v4;
+ struct osmo_sockaddr_str host_v6;
+};
+
+/*! Sets of mslookup_service_host per connected MSC.
+ * When there are more than one MSC connected to this osmo-hlr, this allows keeping separate sets of service addresses
+ * for each MSC. The entry with mslookup_server_msc_wildcard as MSC name is used for all MSCs (if no match for that
+ * particular MSC is found). This corresponds to the VTY config for
+ * 'mslookup' / 'server' / 'msc MSC-1-2-3'.
+ */
+struct mslookup_server_msc_cfg {
+ struct llist_head entry;
+ struct osmo_ipa_name name;
+ struct llist_head service_hosts;
+};
+
+struct mslookup_service_host *mslookup_server_service_get(const struct osmo_ipa_name *msc_name, const char *service);
+
+struct mslookup_service_host *mslookup_server_msc_service_get(struct mslookup_server_msc_cfg *msc, const char *service,
+ bool create);
+int mslookup_server_msc_service_set(struct mslookup_server_msc_cfg *msc, const char *service,
+ const struct osmo_sockaddr_str *addr);
+int mslookup_server_msc_service_del(struct mslookup_server_msc_cfg *msc, const char *service,
+ const struct osmo_sockaddr_str *addr);
+
+extern const struct osmo_ipa_name mslookup_server_msc_wildcard;
+struct mslookup_server_msc_cfg *mslookup_server_msc_get(const struct osmo_ipa_name *msc_name, bool create);
+
+const struct mslookup_service_host *mslookup_server_get_local_gsup_addr();
+void mslookup_server_rx(const struct osmo_mslookup_query *query,
+ struct osmo_mslookup_result *result);
diff --git a/include/osmocom/hlr/timestamp.h b/include/osmocom/hlr/timestamp.h
new file mode 100644
index 0000000..9708985
--- /dev/null
+++ b/include/osmocom/hlr/timestamp.h
@@ -0,0 +1,28 @@
+/* Copyright 2019 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ *
+ * 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/>.
+ *
+ */
+
+#pragma once
+
+#include <sys/time.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+typedef time_t timestamp_t;
+void timestamp_update(timestamp_t *timestamp);
+bool timestamp_age(const timestamp_t *timestamp, uint32_t *age);
diff --git a/src/Makefile.am b/src/Makefile.am
index fec5275..571eaef 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -9,6 +9,7 @@ AM_CFLAGS = \
$(LIBOSMOGSM_CFLAGS) \
$(LIBOSMOVTY_CFLAGS) \
$(LIBOSMOCTRL_CFLAGS) \
+ $(LIBOSMOMSLOOKUP_CFLAGS) \
$(LIBOSMOABIS_CFLAGS) \
$(SQLITE3_CFLAGS) \
$(NULL)
@@ -53,14 +54,18 @@ osmo_hlr_SOURCES = \
gsup_send.c \
hlr_ussd.c \
lu_fsm.c \
+ mslookup_server.c \
+ timestamp.c \
$(NULL)
osmo_hlr_LDADD = \
$(top_builddir)/src/gsupclient/libosmo-gsup-client.la \
+ $(top_builddir)/src/mslookup/libosmo-mslookup.la \
$(LIBOSMOCORE_LIBS) \
$(LIBOSMOGSM_LIBS) \
$(LIBOSMOVTY_LIBS) \
$(LIBOSMOCTRL_LIBS) \
+ $(LIBOSMOMSLOOKUP_LIBS) \
$(LIBOSMOABIS_LIBS) \
$(SQLITE3_LIBS) \
$(NULL)
diff --git a/src/hlr.c b/src/hlr.c
index a33a68c..2cabab4 100644
--- a/src/hlr.c
+++ b/src/hlr.c
@@ -695,6 +695,7 @@ int main(int argc, char **argv)
INIT_LLIST_HEAD(&g_hlr->euse_list);
INIT_LLIST_HEAD(&g_hlr->ss_sessions);
INIT_LLIST_HEAD(&g_hlr->ussd_routes);
+ INIT_LLIST_HEAD(&g_hlr->mslookup.server.local_site_services);
g_hlr->db_file_path = talloc_strdup(g_hlr, HLR_DEFAULT_DB_FILE_PATH);
/* Init default (call independent) SS session guard timeout value */
diff --git a/src/mslookup_server.c b/src/mslookup_server.c
new file mode 100644
index 0000000..9c4dc58
--- /dev/null
+++ b/src/mslookup_server.c
@@ -0,0 +1,376 @@
+/* Copyright 2019 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ *
+ * 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 <string.h>
+#include <errno.h>
+#include <osmocom/core/sockaddr_str.h>
+#include <osmocom/gsm/gsup.h>
+#include <osmocom/mslookup/mslookup.h>
+#include <osmocom/hlr/logging.h>
+#include <osmocom/hlr/hlr.h>
+#include <osmocom/hlr/db.h>
+#include <osmocom/hlr/timestamp.h>
+#include <osmocom/hlr/mslookup_server.h>
+
+static const struct osmo_mslookup_result not_found = {
+ .rc = OSMO_MSLOOKUP_RC_NOT_FOUND,
+ };
+const struct osmo_ipa_name mslookup_server_msc_wildcard = {};
+
+static void set_result(struct osmo_mslookup_result *result,
+ const struct mslookup_service_host *service_host,
+ uint32_t age)
+{
+ if (!osmo_sockaddr_str_is_nonzero(&service_host->host_v4)
+ && !osmo_sockaddr_str_is_nonzero(&service_host->host_v6)) {
+ *result = not_found;
+ return;
+ }
+ result->rc = OSMO_MSLOOKUP_RC_RESULT;
+ result->host_v4 = service_host->host_v4;
+ result->host_v6 = service_host->host_v6;
+ result->age = age;
+}
+
+const struct mslookup_service_host *mslookup_server_get_local_gsup_addr()
+{
+ static struct mslookup_service_host gsup_bind = {};
+ struct mslookup_service_host *host;
+
+ /* Find a HLR/GSUP service set for the server (no VLR unit name) */
+ host = mslookup_server_service_get(&mslookup_server_msc_wildcard, OSMO_MSLOOKUP_SERVICE_HLR_GSUP);
+ if (host)
+ return host;
+
+ /* Try to use the locally configured GSUP bind address */
+ osmo_sockaddr_str_from_str(&gsup_bind.host_v4, g_hlr->gsup_bind_addr, OSMO_GSUP_PORT);
+ if (gsup_bind.host_v4.af == AF_INET6) {
+ gsup_bind.host_v6 = gsup_bind.host_v4;
+ gsup_bind.host_v4 = (struct osmo_sockaddr_str){};
+ }
+ return &gsup_bind;
+}
+
+struct mslookup_server_msc_cfg *mslookup_server_msc_get(const struct osmo_ipa_name *msc_name, bool create)
+{
+ struct llist_head *c = &g_hlr->mslookup.server.local_site_services;
+ struct mslookup_server_msc_cfg *msc;
+
+ if (!msc_name)
+ return NULL;
+
+ llist_for_each_entry(msc, c, entry) {
+ if (osmo_ipa_name_cmp(&msc->name, msc_name))
+ continue;
+ return msc;
+ }
+ if (!create)
+ return NULL;
+
+ msc = talloc_zero(g_hlr, struct mslookup_server_msc_cfg);
+ OSMO_ASSERT(msc);
+ INIT_LLIST_HEAD(&msc->service_hosts);
+ msc->name = *msc_name;
+ llist_add_tail(&msc->entry, c);
+ return msc;
+}
+
+struct mslookup_service_host *mslookup_server_msc_service_get(struct mslookup_server_msc_cfg *msc, const char *service,
+ bool create)
+{
+ struct mslookup_service_host *e;
+ if (!msc)
+ return NULL;
+
+ llist_for_each_entry(e, &msc->service_hosts, entry) {
+ if (!strcmp(e->service, service))
+ return e;
+ }
+
+ if (!create)
+ return NULL;
+
+ e = talloc_zero(msc, struct mslookup_service_host);
+ OSMO_ASSERT(e);
+ OSMO_STRLCPY_ARRAY(e->service, service);
+ llist_add_tail(&e->entry, &msc->service_hosts);
+ return e;
+}
+
+struct mslookup_service_host *mslookup_server_service_get(const struct osmo_ipa_name *msc_name, const char *service)
+{
+ struct mslookup_server_msc_cfg *msc = mslookup_server_msc_get(msc_name, false);
+ if (!msc)
+ return NULL;
+ return mslookup_server_msc_service_get(msc, service, false);
+}
+
+int mslookup_server_msc_service_set(struct mslookup_server_msc_cfg *msc, const char *service,
+ const struct osmo_sockaddr_str *addr)
+{
+ struct mslookup_service_host *e;
+
+ if (!service || !service[0]
+ || strlen(service) > OSMO_MSLOOKUP_SERVICE_MAXLEN)
+ return -EINVAL;
+ if (!addr || !osmo_sockaddr_str_is_nonzero(addr))
+ return -EINVAL;
+
+ e = mslookup_server_msc_service_get(msc, service, true);
+ if (!e)
+ return -EINVAL;
+
+ switch (addr->af) {
+ case AF_INET:
+ e->host_v4 = *addr;
+ break;
+ case AF_INET6:
+ e->host_v6 = *addr;
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+int mslookup_server_msc_service_del(struct mslookup_server_msc_cfg *msc, const char *service,
+ const struct osmo_sockaddr_str *addr)
+{
+ struct mslookup_service_host *e, *n;
+ int deleted = 0;
+
+ if (!msc)
+ return -ENOENT;
+
+ llist_for_each_entry_safe(e, n, &msc->service_hosts, entry) {
+ if (service && strcmp(service, e->service))
+ continue;
+
+ if (addr) {
+ if (!osmo_sockaddr_str_cmp(addr, &e->host_v4)) {
+ e->host_v4 = (struct osmo_sockaddr_str){};
+ /* Removed one addr. If the other is still there, keep the entry. */
+ if (osmo_sockaddr_str_is_nonzero(&e->host_v6))
+ continue;
+ } else if (!osmo_sockaddr_str_cmp(addr, &e->host_v6)) {
+ e->host_v6 = (struct osmo_sockaddr_str){};
+ /* Removed one addr. If the other is still there, keep the entry. */
+ if (osmo_sockaddr_str_is_nonzero(&e->host_v4))
+ continue;
+ } else
+ /* No addr match, keep the entry. */
+ continue;
+ /* Addr matched and none is left. Delete. */
+ }
+ llist_del(&e->entry);
+ talloc_free(e);
+ deleted++;
+ }
+ return deleted;
+}
+
+/* A remote entity is asking us whether we are the home HLR of the given subscriber. */
+static void mslookup_server_rx_hlr_gsup(const struct osmo_mslookup_query *query,
+ struct osmo_mslookup_result *result)
+{
+ const struct mslookup_service_host *host;
+ int rc;
+ switch (query->id.type) {
+ case OSMO_MSLOOKUP_ID_IMSI:
+ rc = db_subscr_exists_by_imsi(g_hlr->dbc, query->id.imsi);
+ break;
+ case OSMO_MSLOOKUP_ID_MSISDN:
+ rc = db_subscr_exists_by_msisdn(g_hlr->dbc, query->id.msisdn);
+ break;
+ default:
+ LOGP(DMSLOOKUP, LOGL_ERROR, "Unknown mslookup ID type: %d\n", query->id.type);
+ *result = not_found;
+ return;
+ }
+
+ if (rc) {
+ LOGP(DMSLOOKUP, LOGL_DEBUG, "%s: does not exist in local HLR\n",
+ osmo_mslookup_result_name_c(OTC_SELECT, query, NULL));
+ *result = not_found;
+ return;
+ }
+
+ LOGP(DMSLOOKUP, LOGL_DEBUG, "%s: found in local HLR\n",
+ osmo_mslookup_result_name_c(OTC_SELECT, query, NULL));
+
+ host = mslookup_server_get_local_gsup_addr();
+
+ set_result(result, host, 0);
+ if (result->rc != OSMO_MSLOOKUP_RC_RESULT) {
+ LOGP(DMSLOOKUP, LOGL_ERROR,
+ "Subscriber found, but error in service '" OSMO_MSLOOKUP_SERVICE_HLR_GSUP "' config:"
+ " v4: " OSMO_SOCKADDR_STR_FMT " v6: " OSMO_SOCKADDR_STR_FMT "\n",
+ OSMO_SOCKADDR_STR_FMT_ARGS(&host->host_v4),
+ OSMO_SOCKADDR_STR_FMT_ARGS(&host->host_v6));
+ }
+}
+
+/* Look in the local HLR record: If the subscriber is "at home" in this HLR and is also currently located at a local
+ * VLR, we will find a valid location updating with vlr_number, and no vlr_via_proxy entry. */
+static bool subscriber_has_done_lu_here_hlr(const struct osmo_mslookup_query *query,
+ uint32_t *lu_age,
+ struct osmo_ipa_name *local_msc_name,
+ struct hlr_subscriber *ret_subscr)
+{
+ struct hlr_subscriber _subscr;
+ int rc;
+ uint32_t age;
+
+ struct hlr_subscriber *subscr = ret_subscr ? : &_subscr;
+
+ switch (query->id.type) {
+ case OSMO_MSLOOKUP_ID_IMSI:
+ rc = db_subscr_get_by_imsi(g_hlr->dbc, query->id.imsi, subscr);
+ break;
+ case OSMO_MSLOOKUP_ID_MSISDN:
+ rc = db_subscr_get_by_msisdn(g_hlr->dbc, query->id.msisdn, subscr);
+ break;
+ default:
+ LOGP(DMSLOOKUP, LOGL_ERROR, "Unknown mslookup ID type: %d\n", query->id.type);
+ return false;
+ }
+
+ if (rc) {
+ LOGP(DMSLOOKUP, LOGL_DEBUG, "%s: does not exist in local HLR\n",
+ osmo_mslookup_result_name_c(OTC_SELECT, query, NULL));
+ return false;
+ }
+
+ if (!subscr->vlr_number[0]) {
+ LOGP(DMSLOOKUP, LOGL_DEBUG, "%s: not attached (vlr_number unset)\n",
+ osmo_mslookup_result_name_c(OTC_SELECT, query, NULL));
+ return false;
+ }
+
+ if (subscr->vlr_via_proxy.len) {
+ /* The VLR is behind a proxy, the subscriber is not attached to a local VLR but a remote one. That
+ * remote proxy should instead respond to the service lookup request. */
+ LOGP(DMSLOOKUP, LOGL_DEBUG, "%s: last attach is not at local VLR, but at VLR '%s' via proxy %s\n",
+ osmo_mslookup_result_name_c(OTC_SELECT, query, NULL),
+ subscr->vlr_number,
+ osmo_ipa_name_to_str(&subscr->vlr_via_proxy));
+ return false;
+ }
+
+ if (!timestamp_age(&subscr->last_lu_seen, &age)) {
+ LOGP(DMSLOOKUP, LOGL_DEBUG, "%s: Invalid last_lu_seen timestamp for subscriber\n",
+ osmo_mslookup_result_name_c(OTC_SELECT, query, NULL));
+ return false;
+ }
+ if (age > g_hlr->mslookup.server.local_attach_max_age) {
+ LOGP(DMSLOOKUP, LOGL_DEBUG, "%s: last attach was here, but too long ago: %us > %us\n",
+ osmo_mslookup_result_name_c(OTC_SELECT, query, NULL),
+ age, g_hlr->mslookup.server.local_attach_max_age);
+ return false;
+ }
+
+ *lu_age = age;
+ osmo_ipa_name_set_str(local_msc_name, subscr->vlr_number);
+ LOGP(DMSLOOKUP, LOGL_DEBUG, "%s: attached %u seconds ago at local VLR %s\n",
+ osmo_mslookup_result_name_c(OTC_SELECT, query, NULL),
+ age, osmo_ipa_name_to_str(local_msc_name));
+
+ return true;
+}
+
+static bool subscriber_has_done_lu_here(const struct osmo_mslookup_query *query,
+ uint32_t *lu_age_p,
+ struct osmo_ipa_name *local_msc_name)
+{
+ bool attached_here;
+ uint32_t lu_age = 0;
+ struct osmo_ipa_name msc_name = {};
+
+ /* First ask the local HLR db, but if the local proxy record indicates a more recent LU, use that instead.
+ * For all usual cases, only one of these will reflect a LU, even if a subscriber had more than one home HLR:
+ * - if the subscriber is known here, we will never proxy.
+ * - if the subscriber is not known here, this local HLR db will never record a LU.
+ * However, if a subscriber was being proxied to a remote home HLR, and if then the subscriber was also added to
+ * the local HLR database, there might occur a situation where both reflect a LU. So, to be safe against all
+ * situations, compare the two entries.
+ */
+ attached_here = subscriber_has_done_lu_here_hlr(query, &lu_age, &msc_name, NULL);
+
+ /* Future: If proxy has a younger lu, replace. */
+
+ if (attached_here && !msc_name.len) {
+ LOGP(DMSLOOKUP, LOGL_ERROR, "%s: attached here, but no VLR name known\n",
+ osmo_mslookup_result_name_c(OTC_SELECT, query, NULL));
+ return false;
+ }
+
+ if (!attached_here) {
+ /* Already logged "not attached" for both local-db and proxy attach */
+ return false;
+ }
+
+ LOGP(DMSLOOKUP, LOGL_INFO, "%s: attached here, at VLR %s\n",
+ osmo_mslookup_result_name_c(OTC_SELECT, query, NULL),
+ osmo_ipa_name_to_str(&msc_name));
+ *lu_age_p = lu_age;
+ *local_msc_name = msc_name;
+ return true;
+}
+
+/* A remote entity is asking us whether we are providing the given service for the given subscriber. */
+void mslookup_server_rx(const struct osmo_mslookup_query *query,
+ struct osmo_mslookup_result *result)
+{
+ const struct mslookup_service_host *service_host;
+ uint32_t age;
+ struct osmo_ipa_name msc_name;
+
+ /* A request for a home HLR: answer exactly if this is the subscriber's home HLR, i.e. the IMSI is listed in the
+ * HLR database. */
+ if (strcmp(query->service, OSMO_MSLOOKUP_SERVICE_HLR_GSUP) == 0)
+ return mslookup_server_rx_hlr_gsup(query, result);
+
+ /* All other service types: answer when the subscriber has done a LU that is either listed in the local HLR or
+ * in the GSUP proxy database: i.e. if the subscriber has done a Location Updating at an VLR belonging to this
+ * HLR. Respond with whichever services are configured in the osmo-hlr.cfg. */
+ if (!subscriber_has_done_lu_here(query, &age, &msc_name)) {
+ *result = not_found;
+ return;
+ }
+
+ /* We've detected a LU here. The VLR where the LU happened is stored in msc_unit_name, and the LU age is stored
+ * in 'age'. Figure out the address configured for that VLR and service name. */
+ service_host = mslookup_server_service_get(&msc_name, query->service);
+
+ if (!service_host) {
+ /* Find such service set globally (no VLR unit name) */
+ service_host = mslookup_server_service_get(&mslookup_server_msc_wildcard, query->service);
+ }
+
+ if (!service_host) {
+ LOGP(DMSLOOKUP, LOGL_ERROR,
+ "%s: subscriber found, but no service %s configured, cannot service lookup request\n",
+ osmo_mslookup_result_name_c(OTC_SELECT, query, NULL),
+ osmo_quote_str_c(OTC_SELECT, query->service, -1));
+ *result = not_found;
+ return;
+ }
+
+ set_result(result, service_host, age);
+}
diff --git a/src/timestamp.c b/src/timestamp.c
new file mode 100644
index 0000000..002857d
--- /dev/null
+++ b/src/timestamp.c
@@ -0,0 +1,53 @@
+/* Copyright 2019 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ *
+ * 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 <osmocom/core/timer.h>
+#include <osmocom/hlr/timestamp.h>
+
+/* Central implementation to set a timestamp to the current time, in case we want to modify this in the future. */
+void timestamp_update(timestamp_t *timestamp)
+{
+ struct timeval tv;
+ time_t raw;
+ struct tm utc;
+ /* The simpler way would be just time(&raw), but by using osmo_gettimeofday() we can also use
+ * osmo_gettimeofday_override for unit tests independent from real time. */
+ osmo_gettimeofday(&tv, NULL);
+ raw = tv.tv_sec;
+ gmtime_r(&raw, &utc);
+ *timestamp = mktime(&utc);
+}
+
+/* Calculate seconds since a given timestamp was taken. Return true for a valid age returned in age_p, return false if
+ * the timestamp is either in the future or the age surpasses uint32_t range. When false is returned, *age_p is set to
+ * UINT32_MAX. */
+bool timestamp_age(const timestamp_t *timestamp, uint32_t *age_p)
+{
+ int64_t age64;
+ timestamp_t now;
+ timestamp_update(&now);
+ age64 = (int64_t)now - (int64_t)(*timestamp);
+ if (age64 < 0 || age64 > UINT32_MAX) {
+ *age_p = UINT32_MAX;
+ return false;
+ }
+ *age_p = (uint32_t)age64;
+ return true;
+}
+