From 84da6b1edb806ac0d7b8a0c40c80f83c4b1d92b9 Mon Sep 17 00:00:00 2001 From: Neels Hofmeyr Date: Fri, 20 May 2016 21:59:55 +0200 Subject: Implement IuCS (large refactoring and addition) osmo-nitb becomes osmo-msc add DIUCS debug log constant add iucs.[hc] add msc vty, remove nitb vty add libiudummy, to avoid linking Iu deps in tests Use new msc_tx_dtap() instead of gsm0808_submit_dtap() libmgcp: add mgcpgw client API bridge calls via mgcpgw Enable MSC specific CTRL commands, bsc_base_ctrl_cmds_install() still needs to be split up. Change-Id: I5b5b6a9678b458affa86800afb1ec726e66eed88 --- src/libmsc/iucs.c | 191 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 191 insertions(+) create mode 100644 src/libmsc/iucs.c (limited to 'src/libmsc/iucs.c') diff --git a/src/libmsc/iucs.c b/src/libmsc/iucs.c new file mode 100644 index 000000000..aeda1406a --- /dev/null +++ b/src/libmsc/iucs.c @@ -0,0 +1,191 @@ +/* Code to manage MSC subscriber connections over IuCS interface */ + +/* + * (C) 2016,2017 by sysmocom s.f.m.c. GmbH + * + * Author: Neels Hofmeyr + * + * All Rights Reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU Affero General Public License as published by + * the Free Software Foundation; either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License + * along with this program. If not, see . + * + */ + +#include + +#include +#include + +#include +#include +#include +#include +#include + +/* For A-interface see libbsc/bsc_api.c subscr_con_allocate() */ +static struct gsm_subscriber_connection *subscr_conn_allocate_iu(struct gsm_network *network, + struct ue_conn_ctx *ue, + uint16_t lac) +{ + struct gsm_subscriber_connection *conn; + + DEBUGP(DIUCS, "Allocating IuCS subscriber conn: lac %d, link_id %p, conn_id %" PRIx32 "\n", + lac, ue->link, ue->conn_id); + + conn = talloc_zero(network, struct gsm_subscriber_connection); + if (!conn) + return NULL; + + conn->network = network; + conn->via_ran = RAN_UTRAN_IU; + conn->iu.ue_ctx = ue; + conn->iu.ue_ctx->rab_assign_addr_enc = network->iu.rab_assign_addr_enc; + conn->lac = lac; + + llist_add_tail(&conn->entry, &network->subscr_conns); + return conn; +} + +static int same_ue_conn(struct ue_conn_ctx *a, struct ue_conn_ctx *b) +{ + if (a == b) + return 1; + return (a->link == b->link) + && (a->conn_id == b->conn_id); +} + +static inline void log_subscribers(struct gsm_network *network) +{ + if (!log_check_level(DIUCS, LOGL_DEBUG)) + return; + + struct gsm_subscriber_connection *conn; + int i = 0; + llist_for_each_entry(conn, &network->subscr_conns, entry) { + DEBUGP(DIUCS, "%3d: %s", i, vlr_subscr_name(conn->vsub)); + switch (conn->via_ran) { + case RAN_UTRAN_IU: + DEBUGPC(DIUCS, " Iu"); + if (conn->iu.ue_ctx) { + DEBUGPC(DIUCS, " link %p, conn_id %d", + conn->iu.ue_ctx->link, + conn->iu.ue_ctx->conn_id + ); + } + break; + case RAN_GERAN_A: + DEBUGPC(DIUCS, " A"); + /* TODO log A-interface connection details */ + break; + case RAN_UNKNOWN: + DEBUGPC(DIUCS, " ?"); + break; + default: + DEBUGPC(DIUCS, " invalid"); + break; + } + DEBUGPC(DIUCS, "\n"); + i++; + } + DEBUGP(DIUCS, "subscribers registered: %d\n", i); +} + +/* Return an existing IuCS subscriber connection record for the given link and + * connection IDs, or return NULL if not found. */ +struct gsm_subscriber_connection *subscr_conn_lookup_iu( + struct gsm_network *network, + struct ue_conn_ctx *ue) +{ + struct gsm_subscriber_connection *conn; + + DEBUGP(DIUCS, "Looking for IuCS subscriber: link_id %p, conn_id %" PRIx32 "\n", + ue->link, ue->conn_id); + log_subscribers(network); + + llist_for_each_entry(conn, &network->subscr_conns, entry) { + if (conn->via_ran != RAN_UTRAN_IU) + continue; + if (!same_ue_conn(conn->iu.ue_ctx, ue)) + continue; + DEBUGP(DIUCS, "Found IuCS subscriber for link_id %p, conn_id %" PRIx32 "\n", + ue->link, ue->conn_id); + return conn; + } + DEBUGP(DIUCS, "No IuCS subscriber found for link_id %p, conn_id %" PRIx32 "\n", + ue->link, ue->conn_id); + return NULL; +} + +/* Receive MM/CC/... message from IuCS (SCCP user SAP). + * msg->dst must reference a struct ue_conn_ctx, which identifies the peer that + * sent the msg. + * + * For A-interface see libbsc/bsc_api.c gsm0408_rcvmsg(). */ +int gsm0408_rcvmsg_iucs(struct gsm_network *network, struct msgb *msg, + uint16_t *lac) +{ + int rc; + struct ue_conn_ctx *ue_ctx; + struct gsm_subscriber_connection *conn; + + ue_ctx = (struct ue_conn_ctx*)msg->dst; + + /* TODO: are there message types that could allow us to skip this + * search? */ + conn = subscr_conn_lookup_iu(network, ue_ctx); + + if (conn && lac && (conn->lac != *lac)) { + LOGP(DIUCS, LOGL_ERROR, "IuCS subscriber has changed LAC" + " within the same connection, discarding connection:" + " %s from LAC %d to %d\n", + vlr_subscr_name(conn->vsub), conn->lac, *lac); + /* Deallocate conn with previous LAC */ + msc_subscr_conn_close(conn, GSM_CAUSE_INV_MAND_INFO); + /* At this point we could be tolerant and allocate a new + * connection, but changing the LAC within the same connection + * is shifty. Rather cancel everything. */ + return -1; + } + + if (conn) { + /* Make sure we don't receive RR over IuCS; otherwise all + * messages handled by gsm0408_dispatch() are of interest (CC, + * MM, SMS, NS_SS, maybe even MM_GPRS and SM_GPRS). */ + struct gsm48_hdr *gh = msgb_l3(msg); + uint8_t pdisc = gh->proto_discr & 0x0f; + OSMO_ASSERT(pdisc != GSM48_PDISC_RR); + + msc_dtap(conn, ue_ctx->conn_id, msg); + rc = 0; + } else { + /* allocate a new connection */ + + if (!lac) { + LOGP(DIUCS, LOGL_ERROR, "New IuCS subscriber" + " but no LAC available. Expecting an InitialUE" + " message containing a LAI IE." + " Dropping connection.\n"); + return -1; + } + + conn = subscr_conn_allocate_iu(network, ue_ctx, *lac); + if (!conn) + abort(); + + /* ownership of conn hereby goes to the MSC: */ + rc = msc_compl_l3(conn, msg, 0); + } + + return rc; +} -- cgit v1.2.3