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 relatd to msc_gsm0808_tx_cipher_mode() in two places.

Change-Id: I5b276853d3af71f5e3f0a031fd17b4fff0580020

1 files changed, 8 insertions, 0 deletions

diff --git a/openbsc/include/openbsc/msc_ifaces.h b/openbsc/include/openbsc/msc_ifaces.h
index cd0039c6f..83aad92a4 100644
--- a/openbsc/include/openbsc/msc_ifaces.h
+++ b/openbsc/include/openbsc/msc_ifaces.h
@@ -37,3 +37,11 @@ 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);