D-GSM 3/n: implement roaming by mslookup in osmo-hlr
Add mslookup client to find remote home HLRs of unknown IMSIs, and
proxy/forward GSUP for those to the right remote HLR instances.
Add remote_hlr.c to manage one GSUP client per remote HLR GSUP address.
Add proxy.c to keep state about remotely handled IMSIs (remote GSUP address,
MSISDN, and probably more in future patches). The mslookup_server that
determines whether a given MSISDN is attached locally now also needs to look in
the proxy record: it is always the osmo-hlr immediately peering for the MSC
that should respond to mslookup service address queries like SIP and SMPP.
(Only gsup.hlr service is always answered by the home HLR.)
Add dgsm.c to set up an mdns mslookup client, ask for IMSI homes, and to decide
which GSUP is handled locally and which needs to go to a remote HLR.
Add full VTY config and VTY tests.
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: I2fe453553c90e6ee527ed13a13089900efd488aa
diff --git a/include/osmocom/hlr/dgsm.h b/include/osmocom/hlr/dgsm.h
new file mode 100644
index 0000000..b3d73e9
--- /dev/null
+++ b/include/osmocom/hlr/dgsm.h
@@ -0,0 +1,46 @@
+/* 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 <osmocom/mslookup/mslookup.h>
+#include <osmocom/hlr/gsup_server.h>
+#include <osmocom/hlr/logging.h>
+#include <osmocom/gsupclient/gsup_peer_id.h>
+#include <osmocom/gsupclient/gsup_req.h>
+
+#define LOG_DGSM(imsi, level, fmt, args...) \
+ LOGP(DDGSM, level, "(IMSI-%s) " fmt, imsi, ##args)
+
+struct vty;
+struct remote_hlr;
+struct hlr_subscriber;
+
+extern void *dgsm_ctx;
+
+void dgsm_init(void *ctx);
+void dgsm_start(void *ctx);
+void dgsm_stop();
+
+bool dgsm_check_forward_gsup_msg(struct osmo_gsup_req *req);
+
+void dgsm_vty_init();
+void dgsm_mdns_client_config_apply(void);
+
+bool hlr_subscr_lu_age(const struct hlr_subscriber *subscr, uint32_t *age_p);