osmo-sgsn/src/sgsn/sgsn_rim.c

68 lines
2.3 KiB
C

#include <stdio.h>
#include <errno.h>
#include <stdint.h>
#include <osmocom/core/msgb.h>
#include <osmocom/gsm/tlv.h>
#include <osmocom/vty/logging.h>
#include <osmocom/gprs/gprs_ns.h>
#include <osmocom/gprs/gprs_bssgp.h>
#include <osmocom/gprs/gprs_bssgp_rim.h>
#include <osmocom/sgsn/sgsn_rim.h>
#include <osmocom/sgsn/debug.h>
/* Find an NSEI for the destination cell, this function works only for GERAN! */
static int find_dest_nsei_geran(struct bssgp_rim_routing_info *dest_rim_ri, uint16_t nsei)
{
struct bssgp_bvc_ctx *bvc_ctx;
OSMO_ASSERT(dest_rim_ri->discr == BSSGP_RIM_ROUTING_INFO_GERAN);
bvc_ctx = btsctx_by_raid_cid(&dest_rim_ri->geran.raid, dest_rim_ri->geran.cid);
if (!bvc_ctx) {
LOGP(DRIM, LOGL_ERROR, "BSSGP RIM (NSEI=%u) cannot find NSEI for destination cell\n", nsei);
return -EINVAL;
}
return bvc_ctx->nsei;
}
int sgsn_rim_rx(struct osmo_bssgp_prim *bp, struct msgb *msg)
{
struct bssgp_ran_information_pdu *pdu = &bp->u.rim_pdu;
int d_nsei;
uint16_t nsei = msgb_nsei(msg);
/* At the moment we only support GERAN, so we block all other network
* types here. */
if (pdu->routing_info_dest.discr != BSSGP_RIM_ROUTING_INFO_GERAN) {
LOGP(DRIM, LOGL_ERROR,
"BSSGP RIM (NSEI=%u) only GERAN supported, destination cell is not a GERAN cell -- rejected.\n",
nsei);
/* At the moment we can only handle GERAN addresses, any other
* type of address will be consideres as an invalid address.
* see also: 3GPP TS 48.018, section 8c.3.1.3 */
return bssgp_tx_status(BSSGP_CAUSE_UNKN_RIM_AI, NULL, msg);
}
if (pdu->routing_info_src.discr != BSSGP_RIM_ROUTING_INFO_GERAN) {
LOGP(DRIM, LOGL_ERROR,
"BSSGP RIM (NSEI=%u) only GERAN supported, source cell is not a GERAN cell -- rejected.\n", nsei);
/* See comment above */
return bssgp_tx_status(BSSGP_CAUSE_UNKN_RIM_AI, NULL, msg);
}
d_nsei = find_dest_nsei_geran(&pdu->routing_info_dest, nsei);
if (d_nsei < 0) {
LOGP(DRIM, LOGL_NOTICE, "BSSGP RIM (NSEI=%u) Cell %s unknown to this sgsn\n",
nsei, bssgp_rim_ri_name(&pdu->routing_info_dest));
/* In case of an invalid destination address we respond with
* a BSSGP STATUS PDU, see also: 3GPP TS 48.018, section 8c.3.1.3 */
return bssgp_tx_status(BSSGP_CAUSE_UNKN_RIM_AI, NULL, msg);
}
/* Forward PDU as it is to the correct interface */
return bssgp_tx_rim(pdu, (uint16_t) d_nsei);
}