diff options
author | Neels Hofmeyr <nhofmeyr@sysmocom.de> | 2017-05-08 15:12:20 +0200 |
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committer | Neels Hofmeyr <neels@hofmeyr.de> | 2017-08-27 03:52:44 +0200 |
commit | ce4d88bd62bf0a1275b5b51dd7b14d16a7642172 (patch) | |
tree | 9c504186fedfe8e576732fac23726d0c8cd0bf3a /include/openbsc/msc_ifaces.h | |
parent | da76052407e0d0bb670c458d66766d18b638c31f (diff) |
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
Diffstat (limited to 'include/openbsc/msc_ifaces.h')
-rw-r--r-- | include/openbsc/msc_ifaces.h | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/include/openbsc/msc_ifaces.h b/include/openbsc/msc_ifaces.h new file mode 100644 index 000000000..83aad92a4 --- /dev/null +++ b/include/openbsc/msc_ifaces.h @@ -0,0 +1,47 @@ +#pragma once + +#include <osmocom/core/msgb.h> +#include <openbsc/gsm_data.h> + +/* These are the interfaces of the MSC layer towards (from?) the BSC and RNC, + * i.e. in the direction towards the mobile device (MS aka UE). + * + * 2G will use the A-interface, + * 3G aka UMTS will use the Iu-interface (for the MSC, it's IuCS). + * + * To allow linking parts of the MSC code without having to include entire + * infrastructures of external libraries, the core transmitting and receiving + * functions are left unimplemented. For example, a unit test does not need to + * link against external ASN1 libraries if it is never going to encode actual + * outgoing messages. It is up to each building scope to implement real world + * functions or to plug mere dummy implementations. + * + * For example, msc_tx_dtap(conn, msg), depending on conn->via_iface, will call + * either iu_tx() or a_tx() [note: at time of writing, the A-interface is not + * yet implemented]. When you try to link against libmsc, you will find that + * the compiler complains about an undefined reference to iu_tx(). If you, + * however, link against libiu as well as the osmo-iuh libs (etc.), iu_tx() is + * available. A unit test may instead simply implement a dummy iu_tx() function + * and not link against osmo-iuh. + */ + +/* Each main linkage must implement this function (see comment above). */ +extern int iu_tx(struct msgb *msg, uint8_t sapi); + +/* So far this is a dummy implemented in libmsc/a_iface.c. When A-interface + * gets implemented, it should be in a separate lib (like libiu), this function + * should move there, and the following comment should remain here: " + * Each main linkage must implement this function (see comment above). + * " */ +extern int a_tx(struct msgb *msg); + +int msc_tx_dtap(struct gsm_subscriber_connection *conn, + struct msgb *msg); + +int msc_gsm48_tx_mm_serv_ack(struct gsm_subscriber_connection *conn); +int msc_gsm48_tx_mm_serv_rej(struct gsm_subscriber_connection *conn, + enum gsm48_reject_value value); + +/* TODO: specific to A interface, move this away */ +int msc_gsm0808_tx_cipher_mode(struct gsm_subscriber_connection *conn, int cipher, + const uint8_t *key, int len, int include_imeisv); |