From 829c060b74f848d06e814c61b789c058f374026d Mon Sep 17 00:00:00 2001 From: Neels Hofmeyr Date: Mon, 30 May 2016 14:56:06 +0200 Subject: add iucs.[hc] Change-Id: I88e981f4c31393a98ae8d61176c65c9251a6f28b --- openbsc/include/openbsc/Makefile.am | 1 + openbsc/include/openbsc/iucs.h | 7 ++ openbsc/src/libmsc/Makefile.am | 1 + openbsc/src/libmsc/iucs.c | 173 ++++++++++++++++++++++++++++++++++++ 4 files changed, 182 insertions(+) create mode 100644 openbsc/include/openbsc/iucs.h create mode 100644 openbsc/src/libmsc/iucs.c (limited to 'openbsc') diff --git a/openbsc/include/openbsc/Makefile.am b/openbsc/include/openbsc/Makefile.am index 6d5bf2492..3f6ba412a 100644 --- a/openbsc/include/openbsc/Makefile.am +++ b/openbsc/include/openbsc/Makefile.am @@ -42,6 +42,7 @@ noinst_HEADERS = \ handover_decision.h \ ipaccess.h \ iu.h \ + iucs.h \ meas_feed.h \ meas_rep.h \ mgcp.h \ diff --git a/openbsc/include/openbsc/iucs.h b/openbsc/include/openbsc/iucs.h new file mode 100644 index 000000000..fb61a5cf1 --- /dev/null +++ b/openbsc/include/openbsc/iucs.h @@ -0,0 +1,7 @@ +#pragma once + +int gsm0408_rcvmsg_iucs(struct gsm_network *network, struct msgb *msg, + uint16_t *lac); + +struct gsm_subscriber_connection *subscr_conn_lookup_iu(struct gsm_network *network, + struct ue_conn_ctx *ue); diff --git a/openbsc/src/libmsc/Makefile.am b/openbsc/src/libmsc/Makefile.am index acb3b1efe..d9f7dc271 100644 --- a/openbsc/src/libmsc/Makefile.am +++ b/openbsc/src/libmsc/Makefile.am @@ -30,6 +30,7 @@ libmsc_a_SOURCES = \ gsm_04_11.c \ gsm_04_80.c \ gsm_subscriber.c \ + iucs.c \ mncc.c \ mncc_builtin.c \ mncc_sock.c \ diff --git a/openbsc/src/libmsc/iucs.c b/openbsc/src/libmsc/iucs.c new file mode 100644 index 000000000..6f9643d76 --- /dev/null +++ b/openbsc/src/libmsc/iucs.c @@ -0,0 +1,173 @@ +#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_iface = IFACE_IU; + conn->iu.ue_ctx = ue; + 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, subscr_name(conn->subscr)); + switch (conn->via_iface) { + case IFACE_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 IFACE_A: + DEBUGPC(DIUCS, " A"); + /* TODO log A-interface connection details */ + break; + case IFACE_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_iface != IFACE_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", + subscr_name(conn->subscr), conn->lac, *lac); + /* Deallocate conn with previous LAC */ + gsm0408_clear_request(conn, 0); + /* 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) { + /* if we already have a connection, handle DTAP. + gsm0408_dispatch() is aka msc_dtap() */ + + /* 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); + + rc = gsm0408_dispatch(conn, msg); + } 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(); + + rc = msc_compl_l3(conn, msg, 0); + if (rc != MSC_CONN_ACCEPT) { + gsm0408_clear_request(conn, 0); + rc = -1; + } + else + rc = 0; + } + + return rc; +} + -- cgit v1.2.3