diff options
Diffstat (limited to 'src/osmo-bsc/abis_osmo.c')
| -rw-r--r-- | src/osmo-bsc/abis_osmo.c | 226 |
1 files changed, 226 insertions, 0 deletions
diff --git a/src/osmo-bsc/abis_osmo.c b/src/osmo-bsc/abis_osmo.c new file mode 100644 index 000000000..48774b4e8 --- /dev/null +++ b/src/osmo-bsc/abis_osmo.c @@ -0,0 +1,226 @@ +/* Osmocom specific protocols over Abis (IPA) */ + +/* (C) 2021 sysmocom - s.f.m.c. GmbH <info@sysmocom.de> + * Author: Pau Espin Pedrol <pespin@sysmocom.de> + * 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 <http://www.gnu.org/licenses/>. + * + */ + +#include <errno.h> +#include <osmocom/core/logging.h> + +#include <osmocom/core/msgb.h> + +#include <osmocom/gsm/protocol/ipaccess.h> +#include <osmocom/gsm/ipa.h> +#include <osmocom/gsm/protocol/gsm_12_21.h> + +#include <osmocom/bsc/abis_osmo.h> +#include <osmocom/bsc/debug.h> +#include <osmocom/bsc/bts.h> +#include <osmocom/bsc/pcuif_proto.h> +#include <osmocom/bsc/neighbor_ident.h> + +#define OM_HEADROOM_SIZE 128 + +//////////////////////////////////////// +// OSMO ABIS extensions (PCU) +/////////////////////////////////////// +#define PCUIF_HDR_SIZE ( sizeof(struct gsm_pcu_if) - sizeof(((struct gsm_pcu_if *)0)->u) ) + +static struct msgb *abis_osmo_pcu_msgb_alloc(uint8_t msg_type, uint8_t bts_nr, size_t extra_size) +{ + struct msgb *msg; + struct gsm_pcu_if *pcu_prim; + msg = msgb_alloc_headroom(OM_HEADROOM_SIZE + sizeof(struct gsm_pcu_if) + extra_size, + OM_HEADROOM_SIZE, "IPA/ABIS/OSMO"); + /* Only header is filled, caller is responible for reserving + filling + * message type specific contents: */ + msgb_put(msg, PCUIF_HDR_SIZE); + pcu_prim = (struct gsm_pcu_if *) msgb_data(msg); + pcu_prim->msg_type = msg_type; + pcu_prim->bts_nr = bts_nr; + return msg; +} + +/* Send a OML NM Message from BSC to BTS */ +static int abis_osmo_pcu_sendmsg(struct gsm_bts *bts, struct msgb *msg) +{ + ipa_prepend_header_ext(msg, IPAC_PROTO_EXT_PCU); + return abis_osmo_sendmsg(bts, msg); +} + +static int abis_osmo_pcu_tx_neigh_addr_cnf(struct gsm_bts *bts, const struct gsm_pcu_if_neigh_addr_req *naddr_req, + uint8_t err_code, const struct osmo_cell_global_id_ps *cgi_ps) +{ + struct msgb *msg = abis_osmo_pcu_msgb_alloc(PCU_IF_MSG_CONTAINER, bts->bts_nr, sizeof(struct gsm_pcu_if_neigh_addr_cnf)); + struct gsm_pcu_if *pcu_prim = (struct gsm_pcu_if *) msgb_data(msg); + struct gsm_pcu_if_neigh_addr_cnf *naddr_cnf = (struct gsm_pcu_if_neigh_addr_cnf *)&pcu_prim->u.container.data[0]; + + msgb_put(msg, sizeof(pcu_prim->u.container) + sizeof(struct gsm_pcu_if_neigh_addr_cnf)); + pcu_prim->u.container.msg_type = PCU_IF_MSG_NEIGH_ADDR_CNF; + osmo_store16be(sizeof(struct gsm_pcu_if_neigh_addr_cnf), &pcu_prim->u.container.length); + + naddr_cnf->orig_req = *naddr_req; + naddr_cnf->err_code = err_code; + if (err_code == 0) { + osmo_store16be(cgi_ps->rai.lac.plmn.mcc, &naddr_cnf->cgi_ps.mcc); + osmo_store16be(cgi_ps->rai.lac.plmn.mnc, &naddr_cnf->cgi_ps.mnc); + naddr_cnf->cgi_ps.mnc_3_digits = cgi_ps->rai.lac.plmn.mnc_3_digits; + osmo_store16be(cgi_ps->rai.lac.lac, &naddr_cnf->cgi_ps.lac); + naddr_cnf->cgi_ps.rac = cgi_ps->rai.rac; + osmo_store16be(cgi_ps->cell_identity, &naddr_cnf->cgi_ps.cell_identity); + } + + return abis_osmo_pcu_sendmsg(bts, msg); +} + +static int rcvmsg_pcu_neigh_addr_req(struct gsm_bts *bts, const struct gsm_pcu_if_neigh_addr_req *naddr_req) +{ + + struct cell_ab ab; + uint16_t local_lac, local_ci; + struct osmo_cell_global_id_ps cgi_ps; + int rc; + + local_lac = osmo_load16be(&naddr_req->local_lac); + local_ci = osmo_load16be(&naddr_req->local_ci); + ab = (struct cell_ab){ + .arfcn = osmo_load16be(&naddr_req->tgt_arfcn), + .bsic = naddr_req->tgt_bsic, + }; + + LOGP(DNM, LOGL_INFO, "(bts=%d) Rx Neighbor Address Resolution Req (ARFCN=%u,BSIC=%u) from (LAC=%u,CI=%u)\n", + bts->nr, ab.arfcn, ab.bsic, local_lac, local_ci); + + if (!cell_ab_valid(&ab)) { + rc = 2; + goto do_fail; + } + + if (neighbor_address_resolution(bts->network, &ab, local_lac, local_ci, &cgi_ps) < 0) { + rc = 1; + goto do_fail; + } + return abis_osmo_pcu_tx_neigh_addr_cnf(bts, naddr_req, 0, &cgi_ps); + +do_fail: + return abis_osmo_pcu_tx_neigh_addr_cnf(bts, naddr_req, rc, NULL); +} + + +static int rcvmsg_pcu_container(struct gsm_bts *bts, struct gsm_pcu_if_container *container, size_t container_len) +{ + int rc; + uint16_t data_length = osmo_load16be(&container->length); + + if (container_len < sizeof(*container) + data_length) { + LOGP(DNM, LOGL_ERROR, "ABIS_OSMO_PCU CONTAINER message inside (%d) too short\n", + container->msg_type); + return -EINVAL; + } + + LOGP(DNM, LOGL_INFO, "(bts=%d) Rx ABIS_OSMO_PCU CONTAINER msg type %u\n", + bts->nr, container->msg_type); + + switch (container->msg_type) { + case PCU_IF_MSG_NEIGH_ADDR_REQ: + if (data_length < sizeof(struct gsm_pcu_if_neigh_addr_req)) { + LOGP(DNM, LOGL_ERROR, "ABIS_OSMO_PCU CONTAINER ANR_CNF message too short\n"); + return -EINVAL; + } + rc = rcvmsg_pcu_neigh_addr_req(bts, (struct gsm_pcu_if_neigh_addr_req *)&container->data); + break; + default: + LOGP(DNM, LOGL_NOTICE, "(bts=%d) Rx ABIS_OSMO_PCU unexpected msg type (%u) inside container!\n", + bts->nr, container->msg_type); + rc = -1; + } + + return rc; +} + +static int rcvmsg_pcu(struct gsm_bts *bts, struct msgb *msg) +{ + struct gsm_pcu_if *pcu_prim; + int rc; + + if (msgb_l2len(msg) < PCUIF_HDR_SIZE) { + LOGP(DNM, LOGL_ERROR, "ABIS_OSMO_PCU message too short\n"); + return -EIO; + } + + pcu_prim = msgb_l2(msg); + LOGP(DNM, LOGL_INFO, "(bts=%d) Rx ABIS_OSMO_PCU msg type %u\n", + pcu_prim->bts_nr, pcu_prim->msg_type); + + switch (pcu_prim->msg_type) { + case PCU_IF_MSG_CONTAINER: + if (msgb_l2len(msg) < PCUIF_HDR_SIZE + sizeof(pcu_prim->u.container)) { + LOGP(DNM, LOGL_ERROR, "ABIS_OSMO_PCU CONTAINER message too short\n"); + rc = -EINVAL; + } else { + rc = rcvmsg_pcu_container(bts, &pcu_prim->u.container, msgb_l2len(msg) - PCUIF_HDR_SIZE); + } + break; + default: + LOGP(DNM, LOGL_NOTICE, "(bts=%d) Rx ABIS_OSMO_PCU unexpected msg type %u!\n", + pcu_prim->bts_nr, pcu_prim->msg_type); + rc = -1; + } + + return rc; +} + +//////////////////////////////////////// +// OSMO ABIS extensions (generic code) +/////////////////////////////////////// + +/* High-Level API */ +/* Entry-point where L2 OSMO from BTS enters the NM code */ +int abis_osmo_rcvmsg(struct msgb *msg) +{ + int rc; + struct e1inp_sign_link *link = msg->dst; + struct gsm_bts *bts = link->trx->bts; + uint8_t *osmo_type = msgb_l2(msg); + msg->l2h = osmo_type + 1; + + switch (*osmo_type) { + case IPAC_PROTO_EXT_PCU: + rc = rcvmsg_pcu(bts, msg); + break; + default: + LOGP(DNM, LOGL_ERROR, "IPAC_PROTO_EXT 0x%x not supported!\n", + *osmo_type); + rc = -EINVAL; + } + + msgb_free(msg); + return rc; +} + + +/* Send a OML NM Message from BSC to BTS */ +int abis_osmo_sendmsg(struct gsm_bts *bts, struct msgb *msg) +{ + msg->dst = bts->osmo_link; + + msg->l2h = msg->data; + + return abis_sendmsg(msg); + +} |