diff options
Diffstat (limited to 'openbsc/src/libmsc/a_iface_bssap.c')
| -rw-r--r-- | openbsc/src/libmsc/a_iface_bssap.c | 647 |
1 files changed, 647 insertions, 0 deletions
diff --git a/openbsc/src/libmsc/a_iface_bssap.c b/openbsc/src/libmsc/a_iface_bssap.c new file mode 100644 index 000000000..258f125fa --- /dev/null +++ b/openbsc/src/libmsc/a_iface_bssap.c @@ -0,0 +1,647 @@ +/* (C) 2017 by Sysmocom s.f.m.c. GmbH + * All Rights Reserved + * + * Author: Philipp Maier + * + * 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 <osmocom/core/utils.h> +#include <osmocom/core/msgb.h> +#include <osmocom/core/logging.h> +#include <osmocom/sigtran/sccp_helpers.h> +#include <osmocom/sccp/sccp_types.h> +#include <osmocom/gsm/gsm0808.h> +#include <osmocom/gsm/gsm0808_utils.h> +#include <openbsc/debug.h> +#include <openbsc/gsm_data.h> +#include <openbsc/a_iface_bssap.h> +#include <openbsc/iu.h> +#include <openbsc/osmo_msc.h> + +/* Addresses of all BSCs which have been registered to this MSC */ +static LLIST_HEAD(bsc_addr_list); + +/* + * Helper functions to lookup and allocate subscribers + */ + +/* Allocate a new subscriber connection */ +static struct gsm_subscriber_connection *subscr_conn_allocate_a(struct gsm_network *network, struct ue_conn_ctx *ue, + uint16_t lac, struct osmo_sccp_user *scu, int conn_id) +{ + struct gsm_subscriber_connection *conn; + + LOGP(DMSC, LOGL_NOTICE, "Allocating A-Interface subscriber conn: lac %i, conn_id %i\n", lac, ue->conn_id); + + conn = talloc_zero(ue, struct gsm_subscriber_connection); + if (!conn) + return NULL; + + conn->network = network; + conn->via_ran = RAN_GERAN_A; + conn->iu.ue_ctx = ue; + conn->iu.ue_ctx->rab_assign_addr_enc = network->iu.rab_assign_addr_enc; + conn->lac = lac; + + conn->a.conn_id = conn_id; + conn->a.scu = scu; + + llist_add_tail(&conn->entry, &network->subscr_conns); + LOGP(DMSC, LOGL_NOTICE, "A-Interface subscriber connection successfully allocated!\n"); + return conn; +} + +/* Return an existing A subscriber connection record for the given + * connection IDs, or return NULL if not found. */ +struct gsm_subscriber_connection *subscr_conn_lookup_a(struct gsm_network *network, int conn_id) +{ + struct gsm_subscriber_connection *conn; + + DEBUGP(DMSC, "Looking for A subscriber: conn_id %i\n", conn_id); + + /* FIXME: log_subscribers() is defined in iucs.c as static inline, if + * maybe this function should be public to reach it from here? */ + /* log_subscribers(network); */ + + llist_for_each_entry(conn, &network->subscr_conns, entry) { + if (conn->via_ran == RAN_GERAN_A && conn->a.conn_id == conn_id) { + DEBUGP(DIUCS, "Found A subscriber for conn_id %i\n", conn_id); + return conn; + } + } + DEBUGP(DMSC, "No A subscriber found for conn_id %i\n", conn_id); + return NULL; +} + +/* + * BSSMAP handling for UNITDATA + */ + +/* Endpoint to handle BSSMAP reset */ +static void bssmap_handle_reset(struct osmo_sccp_user *scu, struct a_conn_info *a_conn_info, struct msgb *msg) +{ + struct a_bsc_addr *addr; + struct a_bsc_addr *known_addr; + bool addr_unknown = true; + + LOGP(DMSC, LOGL_NOTICE, "Rx RESET from BSC %s\n", osmo_sccp_addr_dump(a_conn_info->calling_addr)); + osmo_sccp_tx_unitdata_msg(scu, a_conn_info->called_addr, a_conn_info->calling_addr, gsm0808_create_reset_ack()); + + /* Check if we know this BSC already, if yes, refresh its item */ + llist_for_each_entry(known_addr, &bsc_addr_list, list) { + if (memcmp(&known_addr->calling_addr, a_conn_info->calling_addr, sizeof(*a_conn_info->calling_addr)) == 0) { + LOGP(DMSC, LOGL_NOTICE, "This BSC is already known to this MSC, refreshing its list item\n"); + llist_del(&known_addr->list); + talloc_free(known_addr); + addr_unknown = false; + break; + } + } + if (addr_unknown) + LOGP(DMSC, LOGL_NOTICE, "This BSC is not known to this MSC yet, adding it to list\n"); + + addr = talloc_zero(NULL, struct a_bsc_addr); + memcpy(&addr->calling_addr, a_conn_info->calling_addr, sizeof(addr->calling_addr)); + memcpy(&addr->called_addr, a_conn_info->called_addr, sizeof(addr->called_addr)); + addr->scu = scu; + llist_add(&addr->list, &bsc_addr_list); + + msgb_free(msg); +} + +/* Handle UNITDATA BSSMAP messages */ +static void bssmap_rcvmsg_udt(struct osmo_sccp_user *scu, struct a_conn_info *a_conn_info, struct msgb *msg) +{ + /* Note: When in the MSC role, RESET ACK is the only valid message that + * can be received via UNITDATA */ + + if (msgb_l3len(msg) < 1) { + LOGP(DMSC, LOGL_NOTICE, "Error: No data received -- discarding message!\n"); + return; + } + + LOGP(DMSC, LOGL_NOTICE, "Rx BSC UDT BSSMAP %s\n", gsm0808_bssmap_name(msg->l3h[0])); + + switch (msg->l3h[0]) { + case BSS_MAP_MSG_RESET: + bssmap_handle_reset(scu, a_conn_info, msg); + break; + default: + LOGP(DMSC, LOGL_NOTICE, "Unimplemented message format: %s -- message discarded!\n", + gsm0808_bssmap_name(msg->l3h[0])); + msgb_free(msg); + } +} + +/* Handle incoming connection less data messages */ +void msc_handle_udt(struct osmo_sccp_user *scu, struct a_conn_info *a_conn_info, struct msgb *msg) +{ + /* Note: The only valid message type that can be received + * via UNITDATA are BSS Management messages */ + struct bssmap_header *bs; + + LOGP(DMSC, LOGL_NOTICE, "Rx BSC UDT: %s\n", osmo_hexdump(msgb_l2(msg), msgb_l2len(msg))); + + if (msgb_l2len(msg) < sizeof(*bs)) { + LOGP(DMSC, LOGL_ERROR, "Error: Header is too short -- discarding message!\n"); + msgb_free(msg); + return; + } + + bs = (struct bssmap_header *)msgb_l2(msg); + if (bs->length < msgb_l2len(msg) - sizeof(*bs)) { + LOGP(DMSC, LOGL_ERROR, "Error: Message is too short -- discarding message!\n"); + msgb_free(msg); + return; + } + + switch (bs->type) { + case BSSAP_MSG_BSS_MANAGEMENT: + msg->l3h = &msg->l2h[sizeof(struct bssmap_header)]; + bssmap_rcvmsg_udt(scu, a_conn_info, msg); + break; + default: + LOGP(DMSC, LOGL_ERROR, + "Error: Unimplemented message type: %s -- message discarded!\n", gsm0808_bssmap_name(bs->type)); + msgb_free(msg); + } +} + +/* + * BSSMAP handling for connection oriented data + */ + +/* Endpoint to handle BSSMAP clear request */ +static int bssmap_handle_clear_rqst(struct osmo_sccp_user *scu, struct a_conn_info *a_conn_info, struct msgb *msg) +{ + struct gsm_network *network = a_conn_info->network; + struct tlv_parsed tp; + int rc; + struct msgb *msg_resp; + uint8_t cause; + struct gsm_subscriber_connection *conn; + + LOGP(DMSC, LOGL_NOTICE, "BSC requested to clear connection (conn_id=%i)\n", a_conn_info->conn_id); + + tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l3h + 1, msgb_l3len(msg) - 1, 0, 0); + if (!TLVP_PRESENT(&tp, GSM0808_IE_CAUSE)) { + LOGP(DMSC, LOGL_ERROR, "Cause code is missing -- discarding message!\n"); + goto fail; + } + cause = TLVP_VAL(&tp, GSM0808_IE_CAUSE)[0]; + + /* Respond with clear command */ + msg_resp = gsm0808_create_clear_command(GSM0808_CAUSE_CALL_CONTROL); + rc = osmo_sccp_tx_data_msg(scu, a_conn_info->conn_id, msg_resp); + + /* If possible, inform the MSC about the clear request */ + conn = subscr_conn_lookup_a(network, a_conn_info->conn_id); + if (!conn) + goto fail; + msc_clear_request(conn, cause); + + msgb_free(msg); + return rc; + +fail: + msgb_free(msg); + return -EINVAL; +} + +/* Endpoint to handle BSSMAP clear complete */ +static int bssmap_handle_clear_complete(struct osmo_sccp_user *scu, struct a_conn_info *a_conn_info, struct msgb *msg) +{ + int rc; + + LOGP(DMSC, LOGL_NOTICE, "Releasing connection (conn_id=%i)\n", a_conn_info->conn_id); + rc = osmo_sccp_tx_disconn(scu, a_conn_info->conn_id, + a_conn_info->called_addr, SCCP_RELEASE_CAUSE_END_USER_ORIGINATED); + + msgb_free(msg); + return rc; +} + +/* Endpoint to handle layer 3 complete messages */ +static int bssmap_handle_l3_compl(struct osmo_sccp_user *scu, struct a_conn_info *a_conn_info, struct msgb *msg) +{ + struct tlv_parsed tp; + struct { + uint8_t ident; + struct gsm48_loc_area_id lai; + uint16_t ci; + } __attribute__ ((packed)) lai_ci; + uint16_t mcc; + uint16_t mnc; + uint16_t lac; + uint8_t data_length; + const uint8_t *data; + int rc; + + struct gsm_network *network = a_conn_info->network; + struct ue_conn_ctx *ue; + struct gsm_subscriber_connection *conn; + + LOGP(DMSC, LOGL_NOTICE, "BSC has completed layer 3 connection (conn_id=%i)\n", a_conn_info->conn_id); + + tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l3h + 1, msgb_l3len(msg) - 1, 0, 0); + if (!TLVP_PRESENT(&tp, GSM0808_IE_CELL_IDENTIFIER)) { + LOGP(DMSC, LOGL_ERROR, "Mandatory CELL IDENTIFIER not present -- discarding message!\n"); + goto fail; + } + if (!TLVP_PRESENT(&tp, GSM0808_IE_LAYER_3_INFORMATION)) { + LOGP(DMSC, LOGL_ERROR, "Mandatory LAYER 3 INFORMATION not present -- discarding message!\n"); + goto fail; + } + + /* Parse Cell ID element */ + /* FIXME: Encapsulate this in a parser/generator function inside + * libosmocore, add support for all specified cell identification + * discriminators (see 3GPP ts 3.2.2.17 Cell Identifier) */ + data_length = TLVP_LEN(&tp, GSM0808_IE_CELL_IDENTIFIER); + data = TLVP_VAL(&tp, GSM0808_IE_CELL_IDENTIFIER); + if (sizeof(lai_ci) != data_length) { + LOGP(DMSC, LOGL_ERROR, + "Unable to parse element CELL IDENTIFIER (wrong field length) -- discarding message!\n"); + goto fail; + } + memcpy(&lai_ci, data, sizeof(lai_ci)); + if (lai_ci.ident != CELL_IDENT_WHOLE_GLOBAL) { + LOGP(DMSC, LOGL_ERROR, + "Unable to parse element CELL IDENTIFIER (wrong cell identification discriminator) -- discarding message!\n"); + goto fail; + } + if (gsm48_decode_lai(&lai_ci.lai, &mcc, &mnc, &lac) != 0) { + LOGP(DMSC, LOGL_ERROR, + "Unable to parse element CELL IDENTIFIER (lai decoding failed) -- discarding message!\n"); + goto fail; + } + + /* Parse Layer 3 Information element */ + /* FIXME: This is probably to hackish, compiler also complains "assignment discards ‘const’ qualifier..." */ + msg->l3h = TLVP_VAL(&tp, GSM0808_IE_LAYER_3_INFORMATION); + msg->tail = msg->l3h + TLVP_LEN(&tp, GSM0808_IE_LAYER_3_INFORMATION); + + /* Create new subscriber context */ + ue = ue_conn_ctx_alloc(a_conn_info->calling_addr, a_conn_info->conn_id); + conn = subscr_conn_allocate_a(network, ue, lac, scu, a_conn_info->conn_id); + + /* Handover location update to the MSC code */ + /* msc_compl_l3() takes ownership of dtap_msg + * message buffer */ + rc = msc_compl_l3(conn, msg, 0); + if (rc == MSC_CONN_ACCEPT) { + LOGP(DMSC, LOGL_NOTICE, "User has been accepted by MSC.\n"); + return 0; + } else if (rc == MSC_CONN_REJECT) + LOGP(DMSC, LOGL_NOTICE, "User has been rejected by MSC.\n"); + else + LOGP(DMSC, LOGL_NOTICE, "User has been rejected by MSC (unknown error)\n"); + + return -EINVAL; + +fail: + msgb_free(msg); + return -EINVAL; +} + +/* Endpoint to handle BSSMAP classmark update */ +static int bssmap_classmark_upd(struct osmo_sccp_user *scu, struct a_conn_info *a_conn_info, struct msgb *msg) +{ + struct gsm_network *network = a_conn_info->network; + struct gsm_subscriber_connection *conn; + struct tlv_parsed tp; + const uint8_t *cm2 = NULL; + const uint8_t *cm3 = NULL; + uint8_t cm2_len = 0; + uint8_t cm3_len = 0; + + conn = subscr_conn_lookup_a(network, a_conn_info->conn_id); + if (!conn) + goto fail; + + LOGP(DMSC, LOGL_NOTICE, "BSC sends clasmark update (conn_id=%i)\n", conn->a.conn_id); + + tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l3h + 1, msgb_l3len(msg) - 1, 0, 0); + if (!TLVP_PRESENT(&tp, GSM0808_IE_CLASSMARK_INFORMATION_T2)) { + LOGP(DMSC, LOGL_ERROR, "Mandatory Classmark Information Type 2 not present -- discarding message!\n"); + goto fail; + } + + cm2 = TLVP_VAL(&tp, GSM0808_IE_CLASSMARK_INFORMATION_T2); + cm2_len = TLVP_LEN(&tp, GSM0808_IE_CLASSMARK_INFORMATION_T2); + + if (TLVP_PRESENT(&tp, GSM0808_IE_CLASSMARK_INFORMATION_T3)) { + cm3 = TLVP_VAL(&tp, GSM0808_IE_CLASSMARK_INFORMATION_T3); + cm3_len = TLVP_LEN(&tp, GSM0808_IE_CLASSMARK_INFORMATION_T3); + } + + /* Inform MSC about the classmark change */ + msc_classmark_chg(conn, cm2, cm2_len, cm3, cm3_len); + + msgb_free(msg); + return 0; + +fail: + msgb_free(msg); + return -EINVAL; +} + +/* Endpoint to handle BSSMAP cipher mode complete */ +static int bssmap_ciph_compl(struct osmo_sccp_user *scu, struct a_conn_info *a_conn_info, struct msgb *msg) +{ + /* FIXME: The field GSM0808_IE_LAYER_3_MESSAGE_CONTENTS is optional by + * means of the specification. So there can be messages without L3 info. + * In this case, the code will crash becrause msc_cipher_mode_compl() + * is not able to deal with msg = NULL and apperently + * msc_cipher_mode_compl() was never meant to be used without L3 data. + * This needs to be discussed further! */ + + struct gsm_network *network = a_conn_info->network; + struct gsm_subscriber_connection *conn; + struct tlv_parsed tp; + uint8_t alg_id = 1; + + conn = subscr_conn_lookup_a(network, a_conn_info->conn_id); + if (!conn) + goto fail; + + LOGP(DMSC, LOGL_NOTICE, "BSC sends cipher mode complete (conn_id=%i)\n", conn->a.conn_id); + + tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l3h + 1, msgb_l3len(msg) - 1, 0, 0); + + if (TLVP_PRESENT(&tp, GSM0808_IE_CHOSEN_ENCR_ALG)) { + alg_id = TLVP_VAL(&tp, GSM0808_IE_CHOSEN_ENCR_ALG)[0] - 1; + } + + if (TLVP_PRESENT(&tp, GSM0808_IE_LAYER_3_MESSAGE_CONTENTS)) { + msg->l3h = TLVP_VAL(&tp, GSM0808_IE_LAYER_3_MESSAGE_CONTENTS); + msg->tail = msg->l3h + TLVP_LEN(&tp, GSM0808_IE_LAYER_3_MESSAGE_CONTENTS); + } else { + msgb_free(msg); + msg = NULL; + } + + /* Hand over cipher mode complete message to the MSC, + * msc_cipher_mode_compl() takes ownership for msg */ + msc_cipher_mode_compl(conn, msg, alg_id); + + return 0; +fail: + msgb_free(msg); + return -EINVAL; +} + +/* Endpoint to handle BSSMAP cipher mode reject */ +static int bssmap_ciph_rej(struct osmo_sccp_user *scu, struct a_conn_info *a_conn_info, struct msgb *msg) +{ + struct gsm_network *network = a_conn_info->network; + struct gsm_subscriber_connection *conn; + struct tlv_parsed tp; + uint8_t cause; + + conn = subscr_conn_lookup_a(network, a_conn_info->conn_id); + if (!conn) + goto fail; + + LOGP(DMSC, LOGL_NOTICE, "BSC sends cipher mode reject (conn_id=%i)\n", conn->a.conn_id); + + tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l3h + 1, msgb_l3len(msg) - 1, 0, 0); + if (!TLVP_PRESENT(&tp, BSS_MAP_MSG_CIPHER_MODE_REJECT)) { + LOGP(DMSC, LOGL_ERROR, "Cause code is missing -- discarding message!\n"); + goto fail; + } + + cause = TLVP_VAL(&tp, BSS_MAP_MSG_CIPHER_MODE_REJECT)[0]; + LOGP(DMSC, LOGL_NOTICE, "Cipher mode rejection cause: %i\n", cause); + + /* FIXME: Can we do something meaningful here? e.g. report to the + * msc code somehow that the cipher mode command has failed. */ + + msgb_free(msg); + return 0; +fail: + msgb_free(msg); + return -EINVAL; +} + +/* Endpoint to handle BSSMAP assignment failure */ +static int bssmap_ass_fail(struct osmo_sccp_user *scu, struct a_conn_info *a_conn_info, struct msgb *msg) +{ + struct gsm_network *network = a_conn_info->network; + struct gsm_subscriber_connection *conn; + struct tlv_parsed tp; + uint8_t cause; + uint8_t *rr_cause_ptr = NULL; + uint8_t rr_cause; + + conn = subscr_conn_lookup_a(network, a_conn_info->conn_id); + if (!conn) + goto fail; + + LOGP(DMSC, LOGL_NOTICE, "BSC sends assignment failure message (conn_id=%i)\n", conn->a.conn_id); + + tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l3h + 1, msgb_l3len(msg) - 1, 0, 0); + if (!TLVP_PRESENT(&tp, GSM0808_IE_CAUSE)) { + LOGP(DMSC, LOGL_ERROR, "Cause code is missing -- discarding message!\n"); + goto fail; + } + cause = TLVP_VAL(&tp, GSM0808_IE_CAUSE)[0]; + + if (TLVP_PRESENT(&tp, GSM0808_IE_RR_CAUSE)) { + rr_cause = TLVP_VAL(&tp, GSM0808_IE_RR_CAUSE)[0]; + rr_cause_ptr = &rr_cause; + } + + /* FIXME: In AoIP, the Assignment failure will carry also an optional + * Codec List (BSS Supported) element. It has to be discussed if we + * can ignore this element. If not, The msc_assign_fail() function + * call has to change. However msc_assign_fail() does nothing in the + * end. So probably we can just leave it as it is. Even for AoIP */ + + /* Inform the MSC about the assignment failure event */ + msc_assign_fail(conn, cause, rr_cause_ptr); + + msgb_free(msg); + return 0; +fail: + msgb_free(msg); + return -EINVAL; +} + +/* Endpoint to handle sapi "n" reject */ +static int bssmap_sapi_n_rej(struct osmo_sccp_user *scu, struct a_conn_info *a_conn_info, struct msgb *msg) +{ + struct gsm_network *network = a_conn_info->network; + struct gsm_subscriber_connection *conn; + struct tlv_parsed tp; + uint8_t dlci; + + conn = subscr_conn_lookup_a(network, a_conn_info->conn_id); + if (!conn) + goto fail; + + LOGP(DMSC, LOGL_NOTICE, "BSC sends sapi \"n\" reject message (conn_id=%i)\n", conn->a.conn_id); + + /* Note: The MSC code seems not to care about the cause code, but by + * the specification it is mandatory, so we check its presence. See + * also 3GPP TS 48.008 3.2.1.34 SAPI "n" REJECT */ + tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l3h + 1, msgb_l3len(msg) - 1, 0, 0); + if (!TLVP_PRESENT(&tp, GSM0808_IE_CAUSE)) { + LOGP(DMSC, LOGL_ERROR, "Cause code is missing -- discarding message!\n"); + goto fail; + } + + tlv_parse(&tp, gsm0808_att_tlvdef(), msg->l3h + 1, msgb_l3len(msg) - 1, 0, 0); + if (!TLVP_PRESENT(&tp, GSM0808_IE_DLCI)) { + LOGP(DMSC, LOGL_ERROR, "DLCI is missing -- discarding message!\n"); + goto fail; + } + dlci = TLVP_VAL(&tp, GSM0808_IE_DLCI)[0]; + + /* Inform the MSC about the sapi "n" reject event */ + msc_sapi_n_reject(conn, dlci); + + msgb_free(msg); + return 0; +fail: + msgb_free(msg); + return -EINVAL; +} + +/* Endpoint to handle assignment complete */ +static int bssmap_ass_compl(struct osmo_sccp_user *scu, struct a_conn_info *a_conn_info, struct msgb *msg) +{ + struct gsm_network *network = a_conn_info->network; + struct gsm_subscriber_connection *conn; + + conn = subscr_conn_lookup_a(network, a_conn_info->conn_id); + if (!conn) + goto fail; + + LOGP(DMSC, LOGL_NOTICE, "BSC sends assignment complete message (conn_id=%i)\n", conn->a.conn_id); + + /* Inform the MSC about the assignment completion event */ + msc_rx_sec_mode_compl(conn); + + msgb_free(msg); + return 0; +fail: + msgb_free(msg); + return -EINVAL; +} + +/* Handle incoming connection oriented BSSMAP messages */ +static int bssmap_rcvmsg_dt1(struct osmo_sccp_user *scu, struct a_conn_info *a_conn_info, struct msgb *msg) +{ + if (msgb_l3len(msg) < 1) { + LOGP(DMSC, LOGL_NOTICE, "Error: No data received -- discarding message!\n"); + msgb_free(msg); + return -1; + } + + LOGP(DMSC, LOGL_NOTICE, "Rx MSC DT1 BSSMAP %s\n", gsm0808_bssmap_name(msg->l3h[0])); + + switch (msg->l3h[0]) { + case BSS_MAP_MSG_CLEAR_RQST: + return bssmap_handle_clear_rqst(scu, a_conn_info, msg); + break; + case BSS_MAP_MSG_CLEAR_COMPLETE: + return bssmap_handle_clear_complete(scu, a_conn_info, msg); + break; + case BSS_MAP_MSG_COMPLETE_LAYER_3: + return bssmap_handle_l3_compl(scu, a_conn_info, msg); + break; + case BSS_MAP_MSG_CLASSMARK_UPDATE: + return bssmap_classmark_upd(scu, a_conn_info, msg); + break; + case BSS_MAP_MSG_CIPHER_MODE_COMPLETE: + return bssmap_ciph_compl(scu, a_conn_info, msg); + break; + case BSS_MAP_MSG_CIPHER_MODE_REJECT: + return bssmap_ciph_rej(scu, a_conn_info, msg); + break; + case BSS_MAP_MSG_ASSIGMENT_FAILURE: + return bssmap_ass_fail(scu, a_conn_info, msg); + break; + case BSS_MAP_MSG_SAPI_N_REJECT: + return bssmap_sapi_n_rej(scu, a_conn_info, msg); + break; + case BSS_MAP_MSG_ASSIGMENT_COMPLETE: + return bssmap_ass_compl(scu, a_conn_info, msg); + break; + default: + LOGP(DMSC, LOGL_ERROR, "Unimplemented msg type: %s\n", gsm0808_bssmap_name(msg->l3h[0])); + msgb_free(msg); + return -EINVAL; + } + + return -EINVAL; +} + +/* Endpoint to handle regular BSSAP DTAP messages */ +static int dtap_rcvmsg(struct osmo_sccp_user *scu, struct a_conn_info *a_conn_info, struct msgb *msg) +{ + struct gsm_network *network = a_conn_info->network; + struct gsm_subscriber_connection *conn; + + conn = subscr_conn_lookup_a(network, a_conn_info->conn_id); + if (!conn) { + msgb_free(msg); + return -EINVAL; + } + + LOGP(DMSC, LOGL_NOTICE, "BSC sends layer 3 dtap (conn_id=%i)\n", conn->a.conn_id); + + /* msc_dtap expects the dtap payload in l3h */ + msg->l3h = msg->l2h + 3; + + /* Forward dtap payload into the msc, + * msc_dtap() takes ownership for msg */ + msc_dtap(conn, conn->a.conn_id, msg); + + return 0; +} + +/* Handle incoming connection oriented messages */ +int msc_handle_dt1(struct osmo_sccp_user *scu, struct a_conn_info *a_conn_info, struct msgb *msg) +{ + if (msgb_l2len(msg) < sizeof(struct bssmap_header)) { + LOGP(DMSC, LOGL_NOTICE, "The header is too short -- discarding message!\n"); + msgb_free(msg); + } + + switch (msg->l2h[0]) { + case BSSAP_MSG_BSS_MANAGEMENT: + msg->l3h = &msg->l2h[sizeof(struct bssmap_header)]; + return bssmap_rcvmsg_dt1(scu, a_conn_info, msg); + break; + case BSSAP_MSG_DTAP: + return dtap_rcvmsg(scu, a_conn_info, msg); + break; + default: + LOGP(DMSC, LOGL_ERROR, "Unimplemented BSSAP msg type: %s\n", gsm0808_bssap_name(msg->l2h[0])); + msgb_free(msg); + return -EINVAL; + } + + return -EINVAL; +} + +/* Get a list with all known BSCs */ +struct llist_head *get_bsc_addr_list(void) +{ + return &bsc_addr_list; +} |