mscsplit: various preparations to separate MSC from BSC

Disable large parts of the code that depend on BSC presence. The code sections
disabled by #if BEFORE_MSCSPLIT shall be modified or dropped in the course of
adding the A-interface.

Don't set msg->lchan nor msg->dst.
Don't use lchan in libmsc.
Decouple lac from bts.

Prepare entry/exit point for MSC -> BSC and MSC -> RNC communication:
Add msc_ifaces.[hc], a_iface.c, with a general msc_tx_dtap() to redirect to
different interfaces depending on the actual subscriber connection.
While iu_tx() is going to be functional fairly soon, the a_tx() is going to be
just a dummy for some time (see comment).
Add Iu specific fields in gsm_subscriber_connection: the UE connection pointer
and an indicator for the Integrity Protection status on Iu (to be fully
implemented in later commits).
Add lac member to gsm_subscriber_connection, to allow decoupling from
bts->location_area_code. The conn->lac will actually be set in iu.c in an
upcoming commit ("add iucs.[hc]").

move to libcommon-cs: gsm48_extract_mi(), gsm48_paging_extract_mi().

libmsc: duplicate gsm0808 / gsm48 functions (towards BSC).
In osmo-nitb, libmsc would directly call the functions on the BSC level, not
always via the bsc_api. When separating libmsc from libbsc, some functions are
missing from the linkage.
Hence duplicate these functions to libmsc, add an msc_ prefix for clarity, also
add a _tx to gsm0808_cipher_mode():
* add msc_gsm0808_tx_cipher_mode() (dummy/stub)
* add msc_gsm48_tx_mm_serv_ack()
* add msc_gsm48_tx_mm_serv_rej()
Call these from libmsc instead of
* gsm0808_cipher_mode()
* gsm48_tx_mm_serv_ack()
* gsm48_tx_mm_serv_rej()
Also add a comment related to msc_gsm0808_tx_cipher_mode() in two places.

Remove internal RTP streaming code; OsmoNITB supported that, but for OsmoMSC,
this will be done with an external MGCP gateway.

Remove LCHAN_MODIFY from internal MNCC state machine.

Temporarily disable all paging to be able to link libmsc without libbsc.
Skip the paging part of channel_test because the paging is now disabled.
Employ fake paging shims in order for msc_vlr_tests to still work.

msc_compl_l3(): publish in .h, tweak return value.  Use new libmsc enum values
for return val, to avoid dependency on libbsc headers.  Make callable from
other scopes: publish in osmo_msc.h and remove 'static' in osmo_msc.c

add gsm_encr to subscr_conn
move subscr_request to gsm_subscriber.h
subscr_request_channel() -> subscr_request_conn()
move to libmsc: osmo_stats_vty_add_cmds()
gsm_04_08: remove apply_codec_restrictions()
gsm0408_test: use NULL for root ctx
move to libbsc: gsm_bts_neighbor()
move to libbsc: lchan_next_meas_rep()
move vty config for t3212 to network level (periodic lu)
remove unneccessary linking from some tests
remove handle_abisip_signal()
abis_rsl.c: don't use libvlr from libbsc

gsm_subscriber_connection: put the LAC here, so that it is available without
accessing conn->bts. In bsc_api.c, place this lac in conn for the sake of
transition: Iu and A will use this new field to pass the LAC around, but in a
completely separate OsmoBSC this is not actually needed. It can be removed
again from osmo-bsc.git when the time has come.

Siemens MRPCI: completely drop sending the MRPCI messages for now, they shall
be added in osmo-bsc once the A-Interface code has settled. See OS#2389.

Related: OS#1845 OS#2257 OS#2389
Change-Id: Id3705236350d5f69e447046b0a764bbabc3d493c

1 files changed, 1 insertions, 56 deletions

diff --git a/src/libmsc/vty_interface_layer3.c b/src/libmsc/vty_interface_layer3.c
index c393a8fa6..0106f91b3 100644
--- a/src/libmsc/vty_interface_layer3.c
+++ b/src/libmsc/vty_interface_layer3.c
@@ -553,57 +553,6 @@ DEFUN(ena_subscr_extension,
 	return CMD_WARNING;
 }
 
-DEFUN(ena_subscr_handover,
-      ena_subscr_handover_cmd,
-      "subscriber " SUBSCR_TYPES " ID handover BTS_NR",
-	SUBSCR_HELP "Handover the active connection\n"
-	"Number of the BTS to handover to\n")
-{
-	int ret;
-	struct gsm_subscriber_connection *conn;
-	struct gsm_bts *bts;
-	struct gsm_network *gsmnet = gsmnet_from_vty(vty);
-	struct vlr_subscr *vsub =
-			get_vsub_by_argv(gsmnet, argv[0], argv[1]);
-
-	if (!vsub) {
-		vty_out(vty, "%% No subscriber found for %s %s.%s",
-			argv[0], argv[1], VTY_NEWLINE);
-		return CMD_WARNING;
-	}
-
-	conn = connection_for_subscr(vsub);
-	if (!conn) {
-		vty_out(vty, "%% No active connection for subscriber %s %s.%s",
-			argv[0], argv[1], VTY_NEWLINE);
-		vlr_subscr_put(vsub);
-		return CMD_WARNING;
-	}
-
-	bts = gsm_bts_num(gsmnet, atoi(argv[2]));
-	if (!bts) {
-		vty_out(vty, "%% BTS with number(%d) could not be found.%s",
-			atoi(argv[2]), VTY_NEWLINE);
-		vlr_subscr_put(vsub);
-		return CMD_WARNING;
-	}
-
-	/* now start the handover */
-	ret = bsc_handover_start(conn->lchan, bts);
-	if (ret != 0) {
-		vty_out(vty, "%% Handover failed with errno %d.%s",
-			ret, VTY_NEWLINE);
-	} else {
-		vty_out(vty, "%% Handover started from %s",
-			gsm_lchan_name(conn->lchan));
-		vty_out(vty, " to %s.%s", gsm_lchan_name(conn->ho_lchan),
-			VTY_NEWLINE);
-	}
-
-	vlr_subscr_put(vsub);
-	return CMD_SUCCESS;
-}
-
 #define A3A8_ALG_TYPES "(none|xor|comp128v1)"
 #define A3A8_ALG_HELP 			\
 	"Use No A3A8 algorithm\n"	\
@@ -652,9 +601,7 @@ static int scall_cbfn(unsigned int subsys, unsigned int signal,
 
 	switch (signal) {
 	case S_SCALL_SUCCESS:
-		vty_out(vty, "%% silent call on ARFCN %u timeslot %u%s",
-			sigdata->conn->lchan->ts->trx->arfcn, sigdata->conn->lchan->ts->nr,
-			VTY_NEWLINE);
+		vty_out(vty, "%% silent call success%s", VTY_NEWLINE);
 		break;
 	case S_SCALL_EXPIRED:
 		vty_out(vty, "%% silent call expired paging%s", VTY_NEWLINE);
@@ -670,7 +617,6 @@ DEFUN(show_stats,
 {
 	struct gsm_network *net = gsmnet_from_vty(vty);
 
-	openbsc_vty_print_statistics(vty, net);
 	vty_out(vty, "Location Update         : %lu attach, %lu normal, %lu periodic%s",
 		net->msc_ctrs->ctr[MSC_CTR_LOC_UPDATE_TYPE_ATTACH].current,
 		net->msc_ctrs->ctr[MSC_CTR_LOC_UPDATE_TYPE_NORMAL].current,
@@ -1055,7 +1001,6 @@ int bsc_vty_init_extra(void)
 	install_element(ENABLE_NODE, &ena_subscr_extension_cmd);
 	install_element(ENABLE_NODE, &ena_subscr_authorized_cmd);
 	install_element(ENABLE_NODE, &ena_subscr_a3a8_cmd);
-	install_element(ENABLE_NODE, &ena_subscr_handover_cmd);
 	install_element(ENABLE_NODE, &subscriber_purge_cmd);
 	install_element(ENABLE_NODE, &smsqueue_trigger_cmd);
 	install_element(ENABLE_NODE, &smsqueue_max_cmd);