bsc: Allow to have a list of MSCs/MUXs to connect to

Be able to configure a list of destinations (duplicates allowed)
that will be tried in a round robin fashion. The change is in
the bsc_msc_connection to operate on a list. We achieve the
round robin nature with the same trick used in the paging code
to delete and append the current entry. The nat code was updated
to compile but one can only configure one destination.

3 files changed, 22 insertions, 13 deletions

diff --git a/openbsc/src/osmo-bsc_nat/bsc_nat.c b/openbsc/src/osmo-bsc_nat/bsc_nat.c
index bbb2ae35c..2146da1c4 100644
--- a/openbsc/src/osmo-bsc_nat/bsc_nat.c
+++ b/openbsc/src/osmo-bsc_nat/bsc_nat.c
@@ -1,8 +1,8 @@
 /* BSC Multiplexer/NAT */
 
 /*
- * (C) 2010 by Holger Hans Peter Freyther <zecke@selfish.org>
- * (C) 2010 by On-Waves
+ * (C) 2010-2011 by Holger Hans Peter Freyther <zecke@selfish.org>
+ * (C) 2010-2011 by On-Waves
  * (C) 2009 by Harald Welte <laforge@gnumonks.org>
  * All Rights Reserved
  *
@@ -1432,7 +1432,7 @@ int main(int argc, char **argv)
 		return -4;
 
 	/* connect to the MSC */
-	nat->msc_con = bsc_msc_create(nat->msc_ip, nat->msc_port, 0);
+	nat->msc_con = bsc_msc_create(nat, &nat->dests);
 	if (!nat->msc_con) {
 		fprintf(stderr, "Creating a bsc_msc_connection failed.\n");
 		exit(1);
diff --git a/openbsc/src/osmo-bsc_nat/bsc_nat_utils.c b/openbsc/src/osmo-bsc_nat/bsc_nat_utils.c
index 4e7286e6f..4d1afe2df 100644
--- a/openbsc/src/osmo-bsc_nat/bsc_nat_utils.c
+++ b/openbsc/src/osmo-bsc_nat/bsc_nat_utils.c
@@ -2,8 +2,8 @@
 /* BSC Multiplexer/NAT Utilities */
 
 /*
- * (C) 2010 by Holger Hans Peter Freyther <zecke@selfish.org>
- * (C) 2010 by On-Waves
+ * (C) 2010-2011 by Holger Hans Peter Freyther <zecke@selfish.org>
+ * (C) 2010-2011 by On-Waves
  * All Rights Reserved
  *
  * This program is free software; you can redistribute it and/or modify
@@ -82,10 +82,17 @@ struct bsc_nat *bsc_nat_alloc(void)
 	if (!nat)
 		return NULL;
 
+	nat->main_dest = talloc_zero(nat, struct bsc_msc_dest);
+	if (!nat->main_dest) {
+		talloc_free(nat);
+		return NULL;
+	}
+
 	INIT_LLIST_HEAD(&nat->sccp_connections);
 	INIT_LLIST_HEAD(&nat->bsc_connections);
 	INIT_LLIST_HEAD(&nat->bsc_configs);
 	INIT_LLIST_HEAD(&nat->access_lists);
+	INIT_LLIST_HEAD(&nat->dests);
 
 	nat->stats.sccp.conn = counter_alloc("nat.sccp.conn");
 	nat->stats.sccp.calls = counter_alloc("nat.sccp.calls");
@@ -93,17 +100,20 @@ struct bsc_nat *bsc_nat_alloc(void)
 	nat->stats.bsc.auth_fail = counter_alloc("nat.bsc.auth_fail");
 	nat->stats.msc.reconn = counter_alloc("nat.msc.conn");
 	nat->stats.ussd.reconn = counter_alloc("nat.ussd.conn");
-	nat->msc_ip = talloc_strdup(nat, "127.0.0.1");
-	nat->msc_port = 5000;
 	nat->auth_timeout = 2;
 	nat->ping_timeout = 20;
 	nat->pong_timeout = 5;
+
+	llist_add(&nat->main_dest->list, &nat->dests);
+	nat->main_dest->ip = talloc_strdup(nat, "127.0.0.1");
+	nat->main_dest->port = 5000;
+
 	return nat;
 }
 
 void bsc_nat_set_msc_ip(struct bsc_nat *nat, const char *ip)
 {
-	bsc_replace_string(nat, &nat->msc_ip, ip);
+	bsc_replace_string(nat, &nat->main_dest->ip, ip);
 }
 
 struct bsc_connection *bsc_connection_alloc(struct bsc_nat *nat)
diff --git a/openbsc/src/osmo-bsc_nat/bsc_nat_vty.c b/openbsc/src/osmo-bsc_nat/bsc_nat_vty.c
index ef433caed..ffbfe9b3a 100644
--- a/openbsc/src/osmo-bsc_nat/bsc_nat_vty.c
+++ b/openbsc/src/osmo-bsc_nat/bsc_nat_vty.c
@@ -69,8 +69,8 @@ static int config_write_nat(struct vty *vty)
 	struct bsc_nat_acc_lst *lst;
 
 	vty_out(vty, "nat%s", VTY_NEWLINE);
-	vty_out(vty, " msc ip %s%s", _nat->msc_ip, VTY_NEWLINE);
-	vty_out(vty, " msc port %d%s", _nat->msc_port, VTY_NEWLINE);
+	vty_out(vty, " msc ip %s%s", _nat->main_dest->ip, VTY_NEWLINE);
+	vty_out(vty, " msc port %d%s", _nat->main_dest->port, VTY_NEWLINE);
 	vty_out(vty, " timeout auth %d%s", _nat->auth_timeout, VTY_NEWLINE);
 	vty_out(vty, " timeout ping %d%s", _nat->ping_timeout, VTY_NEWLINE);
 	vty_out(vty, " timeout pong %d%s", _nat->pong_timeout, VTY_NEWLINE);
@@ -311,8 +311,7 @@ DEFUN(show_msc,
 		return CMD_WARNING;
 	}
 
-	vty_out(vty, "MSC on %s:%d is connected: %d%s\n",
-		_nat->msc_con->ip, _nat->msc_con->port,
+	vty_out(vty, "MSC is connected: %d%s\n",
 		_nat->msc_con->is_connected, VTY_NEWLINE);
 	return CMD_SUCCESS;
 }
@@ -357,7 +356,7 @@ DEFUN(cfg_nat_msc_port,
       "msc port <1-65500>",
       "Set the port of the MSC.")
 {
-	_nat->msc_port = atoi(argv[0]);
+	_nat->main_dest->port = atoi(argv[0]);
 	return CMD_SUCCESS;
 }