Remove 'struct bsc_msc_connection' + fix IPA-encapsulated CTRL

The bsc_msc_connection dates back to the old pre-libosmo-sigtran
days, and 90% of the field members weren't used at all (even the
new sigtran specific ones!).  Let's merge what remains into struct
bsc_msc_data.

As a side effect, the already dysfunctional "dest A.B.C.D" VTY
command has been removed from the MSC node.

There's quite a bit of fall-out in the CTRL interface, which was
the code with strongest ties to bsc_msc_connection.  This was
resolved by properly porting CTRL handling over to libosmo-sigtran,
meaning that an IPA/SCCPlite connected MSC can now again send CTRL
GET/SET commands, and can also receive those selective few TRAPs
that old osmo-bsc-sccplite also sent to its MSC[s].

Change-Id: I6b7354f3b23a26bb4eab12213ca3d3b614c8154f
Related: OS#2012

1 files changed, 35 insertions, 0 deletions

diff --git a/src/osmo-bsc/osmo_bsc_sigtran.c b/src/osmo-bsc/osmo_bsc_sigtran.c
index 2c3507d9e..c33124f70 100644
--- a/src/osmo-bsc/osmo_bsc_sigtran.c
+++ b/src/osmo-bsc/osmo_bsc_sigtran.c
@@ -24,6 +24,7 @@
 #include <osmocom/sigtran/sccp_sap.h>
 #include <osmocom/core/linuxlist.h>
 #include <osmocom/gsm/gsm0808.h>
+#include <osmocom/gsm/protocol/ipaccess.h>
 #include <osmocom/core/msgb.h>
 #include <osmocom/bsc/bsc_msc_data.h>
 #include <osmocom/bsc/debug.h>
@@ -512,3 +513,37 @@ fail_auto_cofiguration:
 	     "A-interface: More than one invalid/inclomplete configuration detected, unable to revover - check config file!\n");
 	return -EINVAL;
 }
+
+/* this function receives all messages received on an ASP for a PPID / StreamID that
+ * libosmo-sigtran doesn't know about, such as piggy-backed CTRL and/or MGCP */
+int osmo_ss7_asp_rx_unknown(struct osmo_ss7_asp *asp, int ppid_mux, struct msgb *msg)
+{
+	struct ipaccess_head *iph;
+	struct ipaccess_head_ext *iph_ext;
+
+	if (asp->cfg.proto != OSMO_SS7_ASP_PROT_IPA) {
+		msgb_free(msg);
+		return 0;
+	}
+
+	switch (ppid_mux) {
+	case IPAC_PROTO_OSMO:
+		if (msg->len < sizeof(*iph) + sizeof(*iph_ext)) {
+			LOGP(DMSC, LOGL_ERROR, "The message is too short.\n");
+			msgb_free(msg);
+			return -EINVAL;
+		}
+		iph = (struct ipaccess_head *) msg->data;
+		iph_ext = (struct ipaccess_head_ext *) iph->data;
+		msg->l2h = iph_ext->data;
+		switch (iph_ext->proto) {
+		case IPAC_PROTO_EXT_CTRL:
+			return bsc_sccplite_rx_ctrl(asp, msg);
+		}
+		break;
+	default:
+		break;
+	}
+	msgb_free(msg);
+	return 0; /* OSMO_SS7_UNKNOWN? */
+}