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osmo-bsc/src/osmo-bsc/osmo_bsc_bssap.c

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/* GSM 08.08 BSSMAP handling */
/* (C) 2009-2012 by Holger Hans Peter Freyther <zecke@selfish.org>
* (C) 2009-2012 by On-Waves
* (C) 2017 by Harald Welte <laforge@gnumonks.org>
* 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 <osmocom/core/sockaddr_str.h>
#include <osmocom/mgcp_client/mgcp_client_endpoint_fsm.h>
#include <osmocom/bsc/osmo_bsc.h>
#include <osmocom/bsc/osmo_bsc_grace.h>
#include <osmocom/bsc/osmo_bsc_rf.h>
#include <osmocom/bsc/debug.h>
#include <osmocom/bsc/bsc_subscriber.h>
#include <osmocom/bsc/paging.h>
#include <osmocom/bsc/gsm_04_08_rr.h>
#include <osmocom/bsc/gsm_08_08.h>
#include <osmocom/bsc/bsc_subscr_conn_fsm.h>
#include <osmocom/bsc/codec_pref.h>
#include <osmocom/bsc/data_rate_pref.h>
#include <osmocom/bsc/abis_rsl.h>
#include <osmocom/bsc/handover_fsm.h>
#include <osmocom/bsc/bts.h>
#include <osmocom/bsc/bsc_stats.h>
#include <osmocom/gsm/protocol/gsm_08_08.h>
#include <osmocom/gsm/gsm0808.h>
#include <osmocom/bsc/osmo_bsc_sigtran.h>
#include <osmocom/bsc/osmo_bsc_lcls.h>
#include <osmocom/bsc/a_reset.h>
#include <osmocom/bsc/handover.h>
#include <osmocom/core/fsm.h>
#include <osmocom/core/socket.h>
#include <osmocom/core/sockaddr_str.h>
#include <osmocom/bsc/lcs_loc_req.h>
#include <osmocom/bsc/bssmap_reset.h>
#include <osmocom/bsc/assignment_fsm.h>
#include <osmocom/bsc/vgcs_fsm.h>
#define IP_V4_ADDR_LEN 4
/*
* helpers for the assignment command
*/
/* We expect MSC to provide use with an Osmocom extension TLV in BSSMAP_RESET to
* announce Osmux support */
static void update_msc_osmux_support(struct bsc_msc_data *msc,
struct msgb *msg, unsigned int length)
{
struct tlv_parsed tp;
int rc;
bool old_value = msc->remote_supports_osmux;
rc = osmo_bssap_tlv_parse(&tp, msg->l4h + 1, length - 1);
if (rc < 0)
LOGP(DMSC, LOGL_NOTICE, "Failed parsing TLV looking for Osmux support\n");
msc->remote_supports_osmux = !!TLVP_PRESENT(&tp, GSM0808_IE_OSMO_OSMUX_SUPPORT);
if (old_value != msc->remote_supports_osmux)
LOGP(DMSC, LOGL_INFO, "MSC detected AoIP Osmux support changed: %d->%d\n",
old_value, msc->remote_supports_osmux);
}
static int bssmap_handle_reset_ack(struct bsc_msc_data *msc,
struct msgb *msg, unsigned int length)
{
LOGP(DMSC, LOGL_NOTICE, "RESET ACK from MSC: %s\n",
osmo_sccp_addr_name(osmo_ss7_instance_find(msc->a.cs7_instance),
&msc->a.msc_addr));
/* Inform the FSM that controls the RESET/RESET-ACK procedure
* that we have successfully received the reset-ack message */
a_reset_ack_confirm(msc);
update_msc_osmux_support(msc, msg, length);
return 0;
}
/* Handle MSC sided reset */
static int bssmap_handle_reset(struct bsc_msc_data *msc,
struct msgb *msg, unsigned int length)
{
LOGP(DMSC, LOGL_NOTICE, "RESET from MSC: %s\n",
osmo_sccp_addr_name(osmo_ss7_instance_find(msc->a.cs7_instance),
&msc->a.msc_addr));
update_msc_osmux_support(msc, msg, length);
if (!msc->a.bssmap_reset) {
LOGP(DMSC, LOGL_ERROR, "(msc%d) missing RESET FSM\n", msc->nr);
/* Make sure to shut down all open connections, if any */
osmo_bsc_sigtran_reset(msc);
return -1;
}
/* Normal case: let the reset FSM orchestrate link down / link up callbacks. */
return osmo_fsm_inst_dispatch(msc->a.bssmap_reset->fi, BSSMAP_RESET_EV_RX_RESET, NULL);
}
/* Page a subscriber based on TMSI and LAC via the specified BTS.
* The msc parameter is the MSC which issued the corresponding paging request.
* Log an error if paging failed. */
static void page_subscriber(const struct bsc_paging_params *params, struct gsm_bts *bts, uint32_t lac)
{
int ret;
if (!bsc_grace_allow_new_connection(bsc_gsmnet, bts)) {
LOG_PAGING_BTS(params, bts, DMSC, LOGL_DEBUG, "RF-locked: not paging on this BTS\n");
return;
}
LOG_PAGING_BTS(params, bts, DMSC, LOGL_INFO, "Paging on LAC %u\n", lac);
ret = paging_request_bts(params, bts);
if (ret == 0)
LOG_PAGING_BTS(params, bts, DMSC, LOGL_INFO,
"Paging request failed, or repeated paging on LAC %u\n", lac);
}
static void page_all_bts(const struct bsc_paging_params *params)
{
struct gsm_bts *bts;
llist_for_each_entry(bts, &bsc_gsmnet->bts_list, list)
page_subscriber(params, bts, GSM_LAC_RESERVED_ALL_BTS);
}
static void page_cgi(const struct bsc_paging_params *params)
{
int i;
for (i = 0; i < params->cil.id_list_len; i++) {
const struct osmo_cell_global_id *id = &params->cil.id_list[i].global;
if (!osmo_plmn_cmp(&id->lai.plmn, &bsc_gsmnet->plmn)) {
int paged = 0;
struct gsm_bts *bts;
llist_for_each_entry(bts, &bsc_gsmnet->bts_list, list) {
if (bts->location_area_code != id->lai.lac)
continue;
if (bts->cell_identity != id->cell_identity)
continue;
page_subscriber(params, bts, id->lai.lac);
paged = 1;
}
if (!paged) {
LOG_PAGING(params, DMSC, LOGL_NOTICE, "BTS with LAC %u and CI %u not found\n",
id->lai.lac, id->cell_identity);
}
} else {
LOG_PAGING(params, DMSC, LOGL_DEBUG,
"MCC-MNC in Cell Identifier List (%s) do not match our network (%s)\n",
osmo_plmn_name_c(OTC_SELECT, &id->lai.plmn),
osmo_plmn_name_c(OTC_SELECT, &bsc_gsmnet->plmn));
}
}
}
static void page_lac_and_ci(const struct bsc_paging_params *params)
{
int i;
for (i = 0; i < params->cil.id_list_len; i++) {
const struct osmo_lac_and_ci_id *id = &params->cil.id_list[i].lac_and_ci;
int paged = 0;
struct gsm_bts *bts;
llist_for_each_entry(bts, &bsc_gsmnet->bts_list, list) {
if (bts->location_area_code != id->lac)
continue;
if (bts->cell_identity != id->ci)
continue;
page_subscriber(params, bts, id->lac);
paged = 1;
}
if (!paged) {
LOG_PAGING(params, DMSC, LOGL_NOTICE, "BTS with LAC %u and CI %u not found\n", id->lac, id->ci);
}
}
}
static void page_ci(const struct bsc_paging_params *params)
{
int i;
for (i = 0; i < params->cil.id_list_len; i++) {
uint16_t ci = params->cil.id_list[i].ci;
int paged = 0;
struct gsm_bts *bts;
llist_for_each_entry(bts, &bsc_gsmnet->bts_list, list) {
if (bts->cell_identity != ci)
continue;
page_subscriber(params, bts, GSM_LAC_RESERVED_ALL_BTS);
paged = 1;
}
if (!paged) {
LOG_PAGING(params, DMSC, LOGL_NOTICE, "BTS with CI %u not found\n", ci);
}
}
}
static void page_lai_and_lac(const struct bsc_paging_params *params)
{
int i;
for (i = 0; i < params->cil.id_list_len; i++) {
const struct osmo_location_area_id *id = &params->cil.id_list[i].lai_and_lac;
if (!osmo_plmn_cmp(&id->plmn, &bsc_gsmnet->plmn)) {
int paged = 0;
struct gsm_bts *bts;
llist_for_each_entry(bts, &bsc_gsmnet->bts_list, list) {
if (bts->location_area_code != id->lac)
continue;
page_subscriber(params, bts, id->lac);
paged = 1;
}
if (!paged) {
LOG_PAGING(params, DMSC, LOGL_NOTICE, "BTS with LAC %u not found\n", id->lac);
}
} else {
LOG_PAGING(params, DMSC, LOGL_DEBUG,
"MCC-MNC in Cell Identifier List (%s) do not match our network (%s)\n",
osmo_plmn_name_c(OTC_SELECT, &id->plmn),
osmo_plmn_name_c(OTC_SELECT, &bsc_gsmnet->plmn));
}
}
}
static void page_lac(const struct bsc_paging_params *params)
{
int i;
for (i = 0; i < params->cil.id_list_len; i++) {
uint16_t lac = params->cil.id_list[i].lac;
int paged = 0;
struct gsm_bts *bts;
llist_for_each_entry(bts, &bsc_gsmnet->bts_list, list) {
if (bts->location_area_code != lac)
continue;
page_subscriber(params, bts, lac);
paged = 1;
}
if (!paged) {
LOG_PAGING(params, DMSC, LOGL_NOTICE, "BTS with LAC %u not found\n", lac);
}
}
}
/* GSM 08.08 § 3.2.1.19 */
static int bssmap_handle_paging(struct bsc_msc_data *msc,
struct msgb *msg, unsigned int payload_length)
{
struct tlv_parsed tp;
uint8_t data_length;
int remain;
const uint8_t *data;
struct bsc_paging_params paging = {
.reason = BSC_PAGING_FROM_CN,
.msc = msc,
.tmsi = GSM_RESERVED_TMSI,
};
if (osmo_bssap_tlv_parse(&tp, msg->l4h + 1, payload_length - 1) < 0) {
LOGP(DMSC, LOGL_ERROR, "%s(): tlv_parse() failed\n", __func__);
return -1;
}
remain = payload_length - 1;
if (!TLVP_PRESENT(&tp, GSM0808_IE_IMSI)) {
LOGP(DMSC, LOGL_ERROR, "Mandatory IMSI not present.\n");
return -1;
} else if ((TLVP_VAL(&tp, GSM0808_IE_IMSI)[0] & GSM_MI_TYPE_MASK) != GSM_MI_TYPE_IMSI) {
LOGP(DMSC, LOGL_ERROR, "Wrong content in the IMSI\n");
return -1;
}
remain -= TLVP_LEN(&tp, GSM0808_IE_IMSI);
if (!TLVP_PRESENT(&tp, GSM0808_IE_CELL_IDENTIFIER_LIST)) {
LOGP(DMSC, LOGL_ERROR, "Mandatory CELL IDENTIFIER LIST not present.\n");
return -1;
}
if (TLVP_PRESENT(&tp, GSM0808_IE_TMSI) &&
TLVP_LEN(&tp, GSM0808_IE_TMSI) == 4) {
paging.tmsi = ntohl(tlvp_val32_unal(&tp, GSM0808_IE_TMSI));
remain -= TLVP_LEN(&tp, GSM0808_IE_TMSI);
}
if (remain <= 0) {
LOGP(DMSC, LOGL_ERROR, "Payload too short.\n");
return -1;
}
/*
* parse the IMSI
*/
if (osmo_mobile_identity_decode(&paging.imsi, TLVP_VAL(&tp, GSM0808_IE_IMSI), TLVP_LEN(&tp, GSM0808_IE_IMSI), false)
|| paging.imsi.type != GSM_MI_TYPE_IMSI) {
LOGP(DMSC, LOGL_ERROR, "Paging: could not parse IMSI\n");
return -1;
}
/*
* There are various cell identifier list types defined at 3GPP TS § 08.08, we don't support all
* of them yet. To not disrupt paging operation just because we're lacking some implementation,
* interpret any unknown cell identifier type as "page the entire BSS".
*/
data_length = TLVP_LEN(&tp, GSM0808_IE_CELL_IDENTIFIER_LIST);
data = TLVP_VAL(&tp, GSM0808_IE_CELL_IDENTIFIER_LIST);
if (gsm0808_dec_cell_id_list2(&paging.cil, data, data_length) < 0) {
LOG_PAGING(&paging, DMSC, LOGL_ERROR, "Could not parse Cell Identifier List\n");
return -1;
}
if (paging.cil.id_discr == CELL_IDENT_BSS && data_length != 1) {
LOG_PAGING(&paging, DMSC, LOGL_ERROR, "Cell Identifier List for BSS (0x%x)"
" has invalid length: %u, paging entire BSS anyway (%s)\n",
CELL_IDENT_BSS, data_length, osmo_hexdump(data, data_length));
}
remain = 0;
if (TLVP_PRESENT(&tp, GSM0808_IE_CHANNEL_NEEDED) && TLVP_LEN(&tp, GSM0808_IE_CHANNEL_NEEDED) == 1)
paging.chan_needed = TLVP_VAL(&tp, GSM0808_IE_CHANNEL_NEEDED)[0] & 0x03;
if (TLVP_PRESENT(&tp, GSM0808_IE_EMLPP_PRIORITY)) {
LOG_PAGING(&paging, DMSC, LOGL_ERROR, "eMLPP IE present, but eMLPP is not handled\n");
}
return bsc_paging_start(&paging);
}
int bsc_paging_start(struct bsc_paging_params *params)
{
rate_ctr_inc(rate_ctr_group_get_ctr(bsc_gsmnet->bsc_ctrs, BSC_CTR_PAGING_ATTEMPTED));
if (!params->bsub) {
params->bsub = bsc_subscr_find_or_create_by_imsi(bsc_gsmnet->bsc_subscribers, params->imsi.imsi,
BSUB_USE_PAGING_START);
if (!params->bsub) {
LOG_PAGING(params, DMSC, LOGL_ERROR, "Paging request failed: Could not allocate subscriber\n");
return -EINVAL;
}
}
if (params->tmsi != GSM_RESERVED_TMSI) {
if (bsc_subscr_set_tmsi(params->bsub, params->tmsi) < 0) {
LOG_PAGING(params, DMSC, LOGL_ERROR, "Paging request failed: Could not set TMSI on subscriber\n");
return -EINVAL;
}
}
log_set_context(LOG_CTX_BSC_SUBSCR, params->bsub);
switch (params->cil.id_discr) {
case CELL_IDENT_NO_CELL:
page_all_bts(params);
break;
case CELL_IDENT_WHOLE_GLOBAL:
page_cgi(params);
break;
case CELL_IDENT_LAC_AND_CI:
page_lac_and_ci(params);
break;
case CELL_IDENT_CI:
page_ci(params);
break;
case CELL_IDENT_LAI_AND_LAC:
page_lai_and_lac(params);
break;
case CELL_IDENT_LAC:
page_lac(params);
break;
case CELL_IDENT_BSS:
page_all_bts(params);
break;
default:
LOG_PAGING(params, DMSC, LOGL_NOTICE,
"unimplemented Cell Identifier List type (0x%x), paging entire BSS instead\n",
params->cil.id_discr);
page_all_bts(params);
break;
}
bsc_subscr_put(params->bsub, BSUB_USE_PAGING_START);
log_set_context(LOG_CTX_BSC_SUBSCR, NULL);
return 0;
}
/* Select the best cipher permitted by the intersection of both masks. Return as the n in A5/n, or -1 if the
* intersection is empty. */
int select_best_cipher(uint8_t msc_mask, uint8_t bsc_mask)
{
/* A5/7 ... A5/3: We assume higher is better,
* but: A5/1 is better than A5/2, which is better than A5/0 */
const uint8_t codec_by_strength[8] = { 7, 6, 5, 4, 3, 1, 2, 0 };
uint8_t intersection = msc_mask & bsc_mask;
int i;
for (i = 0; i < ARRAY_SIZE(codec_by_strength); i++) {
uint8_t codec = codec_by_strength[i];
if (intersection & (1 << codec))
return codec;
}
return -1;
}
static int bssmap_handle_clear_cmd(struct gsm_subscriber_connection *conn,
struct msgb *msg, unsigned int length)
{
struct tlv_parsed tp;
enum gsm0808_cause cause_0808;
if (osmo_bssap_tlv_parse(&tp, msg->l4h + 1, length - 1) < 0) {
LOGPFSML(conn->fi, LOGL_ERROR, "%s(): tlv_parse() failed\n", __func__);
return -1;
}
cause_0808 = gsm0808_get_cause(&tp);
if (cause_0808 < 0) {
LOGPFSML(conn->fi, LOGL_ERROR, "Clear Command: Mandatory Cause IE not present.\n");
/* Clear anyway, but without a proper cause. */
cause_0808 = GSM0808_CAUSE_RADIO_INTERFACE_MESSAGE_FAILURE;
}
if (TLVP_PRESENT(&tp, GSM0808_IE_CSFB_INDICATION) &&
!conn->fast_return.last_eutran_plmn_valid) {
LOGPFSML(conn->fi, LOGL_NOTICE,
"Clear Command: CSFB Indication present, "
"but subscriber has no Last Used E-UTRAN PLMN Id! "
"This probably means MSC doesn't support proper return "
"to the last used PLMN after CS fallback.\n");
}
osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_A_CLEAR_CMD, &cause_0808);
return 0;
}
/*
* GSM 08.08 § 3.1.14 cipher mode handling. We will have to pick
* the cipher to be used for this. In case we are already using
* a cipher we will have to send cipher mode reject to the MSC,
* otherwise we will have to pick something that we and the MS
* is supporting. Currently we are doing it in a rather static
* way by picking one encryption or no encryption.
*/
static int bssmap_handle_cipher_mode(struct gsm_subscriber_connection *conn,
struct msgb *msg, unsigned int payload_length)
{
uint16_t len;
const uint8_t *data;
struct tlv_parsed tp;
struct msgb *resp;
int reject_cause = -1;
int include_imeisv = 1;
const uint8_t *enc_key;
uint16_t enc_key_len;
uint8_t enc_bits_msc;
int chosen_cipher;
const struct tlv_p_entry *ie_kc128;
if (!conn || !conn->lchan) {
LOGP(DMSC, LOGL_ERROR, "No lchan/msc_data in cipher mode command.\n");
return -1;
}
if (conn->ciphering_handled) {
LOGP(DMSC, LOGL_ERROR, "Already seen ciphering command. Protocol Error.\n");
reject_cause = GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC;
goto reject;
}
conn->ciphering_handled = 1;
if (osmo_bssap_tlv_parse(&tp, msg->l4h + 1, payload_length - 1) < 0) {
LOGPFSML(conn->fi, LOGL_ERROR, "%s(): tlv_parse() failed\n", __func__);
return -1;
}
if (!TLVP_PRESENT(&tp, GSM0808_IE_ENCRYPTION_INFORMATION)) {
LOGP(DMSC, LOGL_ERROR, "IE Encryption Information missing.\n");
reject_cause = GSM0808_CAUSE_INFORMATION_ELEMENT_OR_FIELD_MISSING;
goto reject;
}
/*
* check if our global setting is allowed
* - Currently we check for A5/0 and A5/1
* - Copy the key if that is necessary
* - Otherwise reject
*/
len = TLVP_LEN(&tp, GSM0808_IE_ENCRYPTION_INFORMATION);
if (len < 1) {
LOGP(DMSC, LOGL_ERROR, "IE Encryption Information is too short.\n");
reject_cause = GSM0808_CAUSE_INCORRECT_VALUE;
goto reject;
}
data = TLVP_VAL(&tp, GSM0808_IE_ENCRYPTION_INFORMATION);
enc_bits_msc = data[0];
enc_key = &data[1];
enc_key_len = len - 1;
if (TLVP_PRESENT(&tp, GSM0808_IE_CIPHER_RESPONSE_MODE))
include_imeisv = TLVP_VAL(&tp, GSM0808_IE_CIPHER_RESPONSE_MODE)[0] & 0x1;
/* Identical to the GSM0808_IE_ENCRYPTION_INFORMATION above:
* a5_encryption == 0 --> 0x01
* a5_encryption == 1 --> 0x02
* a5_encryption == 2 --> 0x04 ... */
enc_bits_msc = data[0];
chosen_cipher = select_best_cipher(enc_bits_msc, bsc_gsmnet->a5_encryption_mask);
if (chosen_cipher < 0) {
LOGP(DMSC, LOGL_ERROR, "Reject: no overlapping A5 ciphers between BSC (0x%02x) "
"and MSC (0x%02x)\n", bsc_gsmnet->a5_encryption_mask, enc_bits_msc);
reject_cause = GSM0808_CAUSE_CIPHERING_ALGORITHM_NOT_SUPPORTED;
goto reject;
}
if (chosen_cipher > 0 && !enc_key_len) {
LOGP(DRSL, LOGL_ERROR, "%s: Need to have an encryption key.\n",
bsc_subscr_name(conn->bsub));
reject_cause = GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC;
goto reject;
}
if (enc_key_len > MAX_A5_KEY_LEN) {
LOGP(DRSL, LOGL_ERROR, "%s: The key is too long: %d\n",
bsc_subscr_name(conn->bsub), len);
reject_cause = GSM0808_CAUSE_PROTOCOL_ERROR_BETWEEN_BSS_AND_MSC;
goto reject;
}
conn->lchan->encr.alg_a5_n = chosen_cipher;
if (enc_key_len) {
conn->lchan->encr.key_len = enc_key_len;
memcpy(conn->lchan->encr.key, enc_key, enc_key_len);
}
if ((ie_kc128 = TLVP_GET(&tp, GSM0808_IE_KC_128))) {
if (ie_kc128->len != sizeof(conn->lchan->encr.kc128)) {
LOGPFSML(conn->fi, LOGL_ERROR, "Kc128 IE has wrong length: %u (expect %zu)\n",
ie_kc128->len, sizeof(conn->lchan->encr.kc128));
reject_cause = GSM0808_CAUSE_INFORMATION_ELEMENT_OR_FIELD_MISSING;
goto reject;
}
memcpy(conn->lchan->encr.kc128, ie_kc128->val, sizeof(conn->lchan->encr.kc128));
conn->lchan->encr.kc128_present = true;
}
if (chosen_cipher == 4 && !conn->lchan->encr.kc128_present) {
LOGPFSML(conn->fi, LOGL_ERROR, "A5/4 encryption selected, but no Kc128\n");
reject_cause = GSM0808_CAUSE_INFORMATION_ELEMENT_OR_FIELD_MISSING;
goto reject;
}
LOGP(DRSL, LOGL_DEBUG, "(subscr %s) Cipher Mode: cipher=%d key=%s kc128=%s include_imeisv=%d\n",
bsc_subscr_name(conn->bsub), chosen_cipher, osmo_hexdump_nospc(enc_key, enc_key_len),
ie_kc128? osmo_hexdump_nospc_c(OTC_SELECT, ie_kc128->val, ie_kc128->len) : "-",
include_imeisv);
if (gsm48_send_rr_ciph_mode(conn->lchan, include_imeisv) < 0) {
reject_cause = GSM0808_CAUSE_RADIO_INTERFACE_FAILURE;
goto reject;
}
return 0;
reject:
resp = gsm0808_create_cipher_reject(reject_cause);
if (!resp) {
LOGP(DMSC, LOGL_ERROR, "Sending the cipher reject failed.\n");
return -1;
}
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_CIPHER_REJECT));
osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_TX_SCCP, resp);
return -1;
}
/* handle LCLS specific IES in BSSMAP ASS REQ */
static void bssmap_handle_ass_req_lcls(struct gsm_subscriber_connection *conn,
const struct tlv_parsed *tp)
{
const uint8_t *config, *control, *gcr;
uint8_t gcr_len;
/* TS 48.008 sec 3.2.2.115 Global Call Reference */
if (TLVP_PRESENT(tp, GSM0808_IE_GLOBAL_CALL_REF)) {
gcr = TLVP_VAL(tp, GSM0808_IE_GLOBAL_CALL_REF);
gcr_len = TLVP_LEN(tp, GSM0808_IE_GLOBAL_CALL_REF);
if (gcr_len > sizeof(conn->lcls.global_call_ref)) {
LOGPFSML(conn->fi, LOGL_ERROR, "Global Call Ref IE of %u bytes is too long: %s\n",
gcr_len, osmo_hexdump_nospc(gcr, gcr_len));
} else if (gcr_len < 13) { /* FIXME: document this magic value 13 */
LOGPFSML(conn->fi, LOGL_ERROR, "Global Call Ref IE of %u bytes is too short: %s\n",
gcr_len, osmo_hexdump_nospc(gcr, gcr_len));
} else {
LOGPFSM(conn->fi, "Setting GCR to %s\n", osmo_hexdump_nospc(gcr, gcr_len));
memcpy(&conn->lcls.global_call_ref, gcr, gcr_len);
conn->lcls.global_call_ref_len = gcr_len;
}
}
config = TLVP_VAL_MINLEN(tp, GSM0808_IE_LCLS_CONFIG, 1);
control = TLVP_VAL_MINLEN(tp, GSM0808_IE_LCLS_CONN_STATUS_CTRL, 1);
if (config || control) {
LOGPFSM(conn->fi, "BSSMAP ASS REQ contains LCLS (%s / %s)\n",
config ? gsm0808_lcls_config_name(*config) : "NULL",
control ? gsm0808_lcls_control_name(*control) : "NULL");
}
/* Update the LCLS state with Config + CSC (if any) */
lcls_update_config(conn, config, control);
/* Do not attempt to perform correlation yet, as during processing of the ASS REQ
* we don't have the MGCP/MGW connections yet, and hence couldn't enable LS. */
}
/* TS 48.008 3.2.1.91 */
static int bssmap_handle_lcls_connect_ctrl(struct gsm_subscriber_connection *conn,
struct msgb *msg, unsigned int length)
{
struct msgb *resp;
struct tlv_parsed tp;
const uint8_t *config, *control;
OSMO_ASSERT(conn);
if (osmo_bssap_tlv_parse(&tp, msg->l4h + 1, length - 1) < 0) {
LOGPFSML(conn->fi, LOGL_ERROR, "%s(): tlv_parse() failed\n", __func__);
return -1;
}
config = TLVP_VAL_MINLEN(&tp, GSM0808_IE_LCLS_CONFIG, 1);
control = TLVP_VAL_MINLEN(&tp, GSM0808_IE_LCLS_CONN_STATUS_CTRL, 1);
LOGPFSM(conn->fi, "Rx LCLS CONNECT CTRL (%s / %s)\n",
config ? gsm0808_lcls_config_name(*config) : "NULL",
control ? gsm0808_lcls_control_name(*control) : "NULL");
if (conn->lcls.global_call_ref_len == 0) {
LOGPFSML(conn->fi, LOGL_ERROR, "Ignoring LCLS as no GCR was set before\n");
return 0;
}
/* Update the LCLS state with Config + CSC (if any) */
lcls_update_config(conn, TLVP_VAL_MINLEN(&tp, GSM0808_IE_LCLS_CONFIG, 1),
TLVP_VAL_MINLEN(&tp, GSM0808_IE_LCLS_CONN_STATUS_CTRL, 1));
lcls_apply_config(conn);
LOGPFSM(conn->fi, "Tx LCLS CONNECT CTRL ACK (%s)\n",
gsm0808_lcls_status_name(lcls_get_status(conn)));
resp = gsm0808_create_lcls_conn_ctrl_ack(lcls_get_status(conn));
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_LCLS_CONNECT_CTRL_ACK));
osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_TX_SCCP, resp);
return 0;
}
/* Select a preferred and an alternative data rate depending on the available
* capabilities. This decision does not include the actual channel load yet,
* this is also the reason why the result is a preferred and an alternate
* setting. The final decision is made in assignment_fsm.c when the actual
* lchan is requested. The preferred lchan will be requested first. If we
* find an alternate setting here, this one will be tried secondly if our
* primary choice fails. */
static int select_data_rates(struct assignment_request *req, struct gsm0808_channel_type *ct,
struct gsm_subscriber_connection *conn)
{
int rc, i, nc = 0;
switch (ct->ch_rate_type) {
case GSM0808_DATA_FULL_BM:
rc = match_data_rate_pref(&req->ch_mode_rate_list[nc], ct, true);
nc += (rc == 0) ? 1 : 0;
break;
case GSM0808_DATA_HALF_LM:
rc = match_data_rate_pref(&req->ch_mode_rate_list[nc], ct, false);
nc += (rc == 0) ? 1 : 0;
break;
case GSM0808_DATA_FULL_PREF_NO_CHANGE:
case GSM0808_DATA_FULL_PREF:
rc = match_data_rate_pref(&req->ch_mode_rate_list[nc], ct, true);
nc += (rc == 0) ? 1 : 0;
rc = match_data_rate_pref(&req->ch_mode_rate_list[nc], ct, false);
nc += (rc == 0) ? 1 : 0;
break;
case GSM0808_DATA_HALF_PREF_NO_CHANGE:
case GSM0808_DATA_HALF_PREF:
rc = match_data_rate_pref(&req->ch_mode_rate_list[nc], ct, false);
nc += (rc == 0) ? 1 : 0;
rc = match_data_rate_pref(&req->ch_mode_rate_list[nc], ct, true);
nc += (rc == 0) ? 1 : 0;
break;
default:
rc = -EINVAL;
break;
}
if (!nc) {
LOGP(DMSC, LOGL_ERROR, "No supported data rate found for channel_type ="
" { ch_indctr=0x%x, ch_rate_type=0x%x, perm_spch=[%s] }\n",
ct->ch_indctr, ct->ch_rate_type, osmo_hexdump(ct->perm_spch, ct->perm_spch_len));
return -EINVAL;
}
for (i = 0; i < nc; i++) {
DEBUGP(DMSC, "Found matching data rate (pref=%d): %s %s for channel_type ="
" { ch_indctr=0x%x, ch_rate_type=0x%x, perm_spch=[ %s] }\n",
i,
req->ch_mode_rate_list[i].chan_rate == CH_RATE_FULL ? "full rate" : "half rate",
get_value_string(gsm48_chan_mode_names, req->ch_mode_rate_list[i].chan_mode),
ct->ch_indctr, ct->ch_rate_type, osmo_hexdump(ct->perm_spch, ct->perm_spch_len));
}
req->n_ch_mode_rate = nc;
return 0;
}
/* Select a preferred and an alternative codec rate depending on the available
* capabilities. This decision does not include the actual lchan availability yet,
* this is also the reason why the result is a preferred and an alternate
* setting. The final decision is made in assignment_fsm.c when the actual
* lchan is requested. The preferred lchan will be requested first. If we
* find an alternate setting here, this one will be tried secondly if our
* primary choice fails. */
static int select_codecs(struct assignment_request *req, const struct gsm0808_channel_type *ct,
struct gsm_subscriber_connection *conn, struct gsm_bts *bts)
{
int rc, i, nc = 0;
struct bsc_msc_data *msc;
if (!bts) {
LOGP(DMSC, LOGL_ERROR, "No lchan, cannot select codecs\n");
return -EINVAL;
}
msc = conn->sccp.msc;
switch (ct->ch_rate_type) {
case GSM0808_SPEECH_FULL_BM:
rc = match_codec_pref(&req->ch_mode_rate_list[nc], ct, &conn->codec_list, msc, bts,
RATE_PREF_FR);
nc += (rc == 0) ? 1 : 0;
break;
case GSM0808_SPEECH_HALF_LM:
rc = match_codec_pref(&req->ch_mode_rate_list[nc], ct, &conn->codec_list, msc, bts,
RATE_PREF_HR);
nc += (rc == 0) ? 1 : 0;
break;
case GSM0808_SPEECH_PERM:
case GSM0808_SPEECH_PERM_NO_CHANGE:
case GSM0808_SPEECH_FULL_PREF_NO_CHANGE:
case GSM0808_SPEECH_FULL_PREF:
rc = match_codec_pref(&req->ch_mode_rate_list[nc], ct, &conn->codec_list, msc, bts,
RATE_PREF_FR);
nc += (rc == 0) ? 1 : 0;
rc = match_codec_pref(&req->ch_mode_rate_list[nc], ct, &conn->codec_list, msc, bts,
RATE_PREF_HR);
nc += (rc == 0) ? 1 : 0;
break;
case GSM0808_SPEECH_HALF_PREF_NO_CHANGE:
case GSM0808_SPEECH_HALF_PREF:
rc = match_codec_pref(&req->ch_mode_rate_list[nc], ct, &conn->codec_list, msc, bts,
RATE_PREF_HR);
nc += (rc == 0) ? 1 : 0;
rc = match_codec_pref(&req->ch_mode_rate_list[nc], ct, &conn->codec_list, msc, bts,
RATE_PREF_FR);
nc += (rc == 0) ? 1 : 0;
break;
default:
rc = -EINVAL;
break;
}
if (!nc) {
LOGP(DMSC, LOGL_ERROR, "No supported audio type found for channel_type ="
" { ch_indctr=0x%x, ch_rate_type=0x%x, perm_spch=[%s] }\n",
ct->ch_indctr, ct->ch_rate_type, osmo_hexdump(ct->perm_spch, ct->perm_spch_len));
/* TODO: actually output codec names, e.g. implement
* gsm0808_permitted_speech_names[] and iterate perm_spch. */
return -EINVAL;
}
for (i = 0; i < nc; i++ ) {
DEBUGP(DMSC, "Found matching audio type (pref=%d): %s %s for channel_type ="
" { ch_indctr=0x%x, ch_rate_type=0x%x, perm_spch=[ %s] }\n",
i,
req->ch_mode_rate_list[i].chan_rate == CH_RATE_FULL ? "full rate" : "half rate",
get_value_string(gsm48_chan_mode_names, req->ch_mode_rate_list[i].chan_mode),
ct->ch_indctr, ct->ch_rate_type, osmo_hexdump(ct->perm_spch, ct->perm_spch_len));
}
req->n_ch_mode_rate = nc;
return 0;
}
static int select_sign_chan(struct assignment_request *req, struct gsm0808_channel_type *ct)
{
int i, nc = 0;
switch (ct->ch_rate_type) {
case GSM0808_SIGN_ANY:
req->ch_mode_rate_list[nc++].chan_rate = CH_RATE_SDCCH;
req->ch_mode_rate_list[nc++].chan_rate = CH_RATE_HALF;
req->ch_mode_rate_list[nc++].chan_rate = CH_RATE_FULL;
break;
case GSM0808_SIGN_SDCCH:
req->ch_mode_rate_list[nc++].chan_rate = CH_RATE_SDCCH;
break;
case GSM0808_SIGN_SDCCH_FULL_BM:
req->ch_mode_rate_list[nc++].chan_rate = CH_RATE_SDCCH;
req->ch_mode_rate_list[nc++].chan_rate = CH_RATE_FULL;
break;
case GSM0808_SIGN_SDCCH_HALF_LM:
req->ch_mode_rate_list[nc++].chan_rate = CH_RATE_SDCCH;
req->ch_mode_rate_list[nc++].chan_rate = CH_RATE_HALF;
break;
case GSM0808_SIGN_FULL_BM:
req->ch_mode_rate_list[nc++].chan_rate = CH_RATE_FULL;
break;
case GSM0808_SIGN_HALF_LM:
req->ch_mode_rate_list[nc++].chan_rate = CH_RATE_HALF;
break;
case GSM0808_SIGN_FULL_PREF:
case GSM0808_SIGN_FULL_PREF_NO_CHANGE:
req->ch_mode_rate_list[nc++].chan_rate = CH_RATE_FULL;
req->ch_mode_rate_list[nc++].chan_rate = CH_RATE_HALF;
break;
case GSM0808_SIGN_HALF_PREF:
case GSM0808_SIGN_HALF_PREF_NO_CHANGE:
req->ch_mode_rate_list[nc++].chan_rate = CH_RATE_HALF;
req->ch_mode_rate_list[nc++].chan_rate = CH_RATE_FULL;
break;
default:
break;
}
for (i = 0; i < nc; i++)
req->ch_mode_rate_list[i].chan_mode = GSM48_CMODE_SIGN;
req->n_ch_mode_rate = nc;
return nc > 0 ? 0 : -EINVAL;
}
static int bssmap_handle_ass_req_tp_cic(struct tlv_parsed *tp, bool aoip, uint16_t *cic, uint8_t *cause)
{
if (TLVP_PRESENT(tp, GSM0808_IE_CIRCUIT_IDENTITY_CODE)) {
/* CIC is permitted in both AoIP and SCCPlite */
*cic = osmo_load16be(TLVP_VAL(tp, GSM0808_IE_CIRCUIT_IDENTITY_CODE));
return 0;
}
if (!aoip) {
/* no CIC but SCCPlite: illegal */
LOGP(DMSC, LOGL_ERROR, "SCCPlite MSC, but no CIC in ASSIGN REQ?\n");
*cause = GSM0808_CAUSE_INFORMATION_ELEMENT_OR_FIELD_MISSING;
return -1;
}
return 0;
}
static int bssmap_handle_ass_req_tp_rtp_addr(struct tlv_parsed *tp, bool aoip, char *msc_rtp_addr,
size_t msc_rtp_addr_len, uint16_t *msc_rtp_port, uint8_t *cause)
{
struct sockaddr_storage rtp_addr;
int rc;
unsigned int rc2;
if (TLVP_PRESENT(tp, GSM0808_IE_AOIP_TRASP_ADDR)) {
if (!aoip) {
/* SCCPlite and AoIP transport address: illegal */
LOGP(DMSC, LOGL_ERROR, "AoIP Transport address over IPA ?!?\n");
*cause = GSM0808_CAUSE_INCORRECT_VALUE;
return -1;
}
/* Decode AoIP transport address element */
rc = gsm0808_dec_aoip_trasp_addr(&rtp_addr,
TLVP_VAL(tp, GSM0808_IE_AOIP_TRASP_ADDR),
TLVP_LEN(tp, GSM0808_IE_AOIP_TRASP_ADDR));
if (rc < 0) {
LOGP(DMSC, LOGL_ERROR, "Unable to decode AoIP transport address.\n");
*cause = GSM0808_CAUSE_INCORRECT_VALUE;
return -1;
}
rc2 = osmo_sockaddr_to_str_and_uint(msc_rtp_addr, msc_rtp_addr_len, msc_rtp_port,
(const struct sockaddr *)&rtp_addr);
if (!rc2 || rc >= msc_rtp_addr_len) {
LOGP(DMSC, LOGL_ERROR, "Assignment request: RTP address is too long\n");
*cause = GSM0808_CAUSE_REQ_CODEC_TYPE_OR_CONFIG_UNAVAIL;
return -1;
}
return 0;
}
if (aoip) {
/* no AoIP transport level address but AoIP transport: illegal */
LOGP(DMSC, LOGL_ERROR, "AoIP transport address missing in ASSIGN REQ, "
"audio would not work; rejecting\n");
*cause = GSM0808_CAUSE_INFORMATION_ELEMENT_OR_FIELD_MISSING;
return -1;
}
return 0;
}
static int bssmap_handle_ass_req_tp_osmux(struct gsm_subscriber_connection *conn, struct tlv_parsed *tp,
bool *use_osmux, uint8_t *osmux_cid, uint8_t *cause)
{
int rc;
if (TLVP_PRESENT(tp, GSM0808_IE_OSMO_OSMUX_CID)) {
if (conn->sccp.msc->use_osmux == OSMUX_USAGE_OFF) {
LOGP(DMSC, LOGL_ERROR, "MSC using Osmux but we have it disabled.\n");
*cause = GSM0808_CAUSE_INCORRECT_VALUE;
return -1;
}
*use_osmux = true;
rc = gsm0808_dec_osmux_cid(osmux_cid,
TLVP_VAL(tp, GSM0808_IE_OSMO_OSMUX_CID),
TLVP_LEN(tp, GSM0808_IE_OSMO_OSMUX_CID));
if (rc < 0) {
LOGP(DMSC, LOGL_ERROR, "Unable to decode Osmux CID.\n");
*cause = GSM0808_CAUSE_INCORRECT_VALUE;
return -1;
}
return 0;
}
if (conn->sccp.msc->use_osmux == OSMUX_USAGE_ONLY) {
LOGP(DMSC, LOGL_ERROR, "MSC not using Osmux but we are forced to use it.\n");
*cause = GSM0808_CAUSE_INCORRECT_VALUE;
return -1;
}
if (conn->sccp.msc->use_osmux == OSMUX_USAGE_ON)
LOGP(DMSC, LOGL_NOTICE, "MSC not using Osmux but we have Osmux enabled.\n");
return 0;
}
static int bssmap_handle_ass_req_tp_codec_list(struct gsm_subscriber_connection *conn, struct tlv_parsed *tp, bool aoip,
uint8_t *cause)
{
int rc;
/* Decode speech codec list. First set len = 0. */
conn->codec_list = (struct gsm0808_speech_codec_list){};
/* Check for speech codec list element */
if (TLVP_PRESENT(tp, GSM0808_IE_SPEECH_CODEC_LIST)) {
/* Decode Speech Codec list */
rc = gsm0808_dec_speech_codec_list(&conn->codec_list,
TLVP_VAL(tp, GSM0808_IE_SPEECH_CODEC_LIST),
TLVP_LEN(tp, GSM0808_IE_SPEECH_CODEC_LIST));
if (rc < 0) {
LOGP(DMSC, LOGL_ERROR, "Unable to decode speech codec list\n");
*cause = GSM0808_CAUSE_INCORRECT_VALUE;
return -1;
}
}
if (aoip && !conn->codec_list.len) {
LOGP(DMSC, LOGL_ERROR, "%s: AoIP Assignment Request:"
" Missing or empty Speech Codec List IE\n", bsc_subscr_name(conn->bsub));
*cause = GSM0808_CAUSE_INFORMATION_ELEMENT_OR_FIELD_MISSING;
return -1;
}
return 0;
}
static int bssmap_handle_ass_req_ct_data(struct gsm_subscriber_connection *conn, struct tlv_parsed *tp,
struct gsm0808_channel_type *ct, struct assignment_request *req,
uint8_t *cause)
{
bool aoip = gscon_is_aoip(conn);
int rc;
*req = (struct assignment_request){
.assign_for = ASSIGN_FOR_BSSMAP_REQ,
.aoip = aoip,
};
if (bssmap_handle_ass_req_tp_cic(tp, aoip, &req->msc_assigned_cic, cause) < 0)
return -1;
if (bssmap_handle_ass_req_tp_rtp_addr(tp, aoip, req->msc_rtp_addr, sizeof(req->msc_rtp_addr), &req->msc_rtp_port, cause) < 0)
return -1;
/* According to 3GPP TS 48.008 § 3.2.1.1 note 13, the codec list IE
* shall be included for aoip unless channel type is signalling. */
if (bssmap_handle_ass_req_tp_codec_list(conn, tp, aoip, cause) < 0)
return -1;
rc = select_data_rates(req, ct, conn);
if (rc < 0) {
*cause = GSM0808_CAUSE_REQ_CODEC_TYPE_OR_CONFIG_UNAVAIL;
return -1;
}
return 0;
}
int bssmap_handle_ass_req_ct_speech(struct gsm_subscriber_connection *conn, struct gsm_bts *bts,
struct tlv_parsed *tp, struct gsm0808_channel_type *ct,
struct assignment_request *req, uint8_t *cause)
{
bool aoip = gscon_is_aoip(conn);
int rc;
*req = (struct assignment_request){
.assign_for = ASSIGN_FOR_BSSMAP_REQ,
.aoip = aoip,
};
if (bssmap_handle_ass_req_tp_cic(tp, aoip, &req->msc_assigned_cic, cause) < 0)
return -1;
if (bssmap_handle_ass_req_tp_rtp_addr(tp, aoip, req->msc_rtp_addr, sizeof(req->msc_rtp_addr), &req->msc_rtp_port, cause) < 0)
return -1;
if (bssmap_handle_ass_req_tp_osmux(conn, tp, &req->use_osmux, &req->osmux_cid, cause) < 0)
return -1;
if (bssmap_handle_ass_req_tp_codec_list(conn, tp, aoip, cause) < 0)
return -1;
/* Match codec information from the assignment command against the
* local preferences of the BSC and BTS */
rc = select_codecs(req, ct, conn, bts);
if (rc < 0) {
*cause = GSM0808_CAUSE_REQ_CODEC_TYPE_OR_CONFIG_UNAVAIL;
return -1;
}
return 0;
}
static int bssmap_handle_ass_req_ct_sign(struct gsm_subscriber_connection *conn, struct gsm0808_channel_type *ct,
struct assignment_request *req, uint8_t *cause)
{
int rc;
*req = (struct assignment_request){
.assign_for = ASSIGN_FOR_BSSMAP_REQ,
.aoip = gscon_is_aoip(conn),
};
rc = select_sign_chan(req, ct);
if (rc < 0) {
*cause = GSM0808_CAUSE_INCORRECT_VALUE;
return rc;
}
return 0;
}
/*
* Handle the assignment request message.
*
* See §3.2.1.1 for the message type
*/
static int bssmap_handle_assignm_req(struct gsm_subscriber_connection *conn,
struct msgb *msg, unsigned int length)
{
struct msgb *resp;
struct tlv_parsed tp;
struct gsm0808_channel_type ct;
struct gsm0808_group_callref gc;
uint8_t cause;
int rc;
struct assignment_request req = {};
if (!conn) {
LOGP(DMSC, LOGL_ERROR,
"No lchan/msc_data in Assignment Request\n");
return -1;
}
if (osmo_bssap_tlv_parse(&tp, msg->l4h + 1, length - 1) < 0) {
LOGPFSML(conn->fi, LOGL_ERROR, "%s(): tlv_parse() failed\n", __func__);
return -1;
}
/* Check for channel type element, if its missing, immediately reject */
if (!TLVP_PRESENT(&tp, GSM0808_IE_CHANNEL_TYPE)) {
LOGP(DMSC, LOGL_ERROR, "Mandatory channel type not present.\n");
cause = GSM0808_CAUSE_INFORMATION_ELEMENT_OR_FIELD_MISSING;
goto reject;
}
/* Decode Channel Type element */
rc = gsm0808_dec_channel_type(&ct, TLVP_VAL(&tp, GSM0808_IE_CHANNEL_TYPE),
TLVP_LEN(&tp, GSM0808_IE_CHANNEL_TYPE));
if (rc < 0) {
LOGP(DMSC, LOGL_ERROR, "unable to decode channel type.\n");
cause = GSM0808_CAUSE_INCORRECT_VALUE;
goto reject;
}
/* Check for assignment to VGCS channel. */
if (TLVP_PRESENT(&tp, GSM0808_IE_GROUP_CALL_REFERENCE)) {
struct gsm_bts *bts = conn_get_bts(conn);
OSMO_ASSERT(bts);
/* Decode Group Call Reference. */
rc = gsm0808_dec_group_callref(&gc, TLVP_VAL(&tp, GSM0808_IE_GROUP_CALL_REFERENCE),
TLVP_LEN(&tp, GSM0808_IE_GROUP_CALL_REFERENCE));
if (rc < 0) {
LOGP(DMSC, LOGL_ERROR, "Unable to decode Group Call Reference.\n");
cause = GSM0808_CAUSE_INCORRECT_VALUE;
goto reject;
}
req.target_lchan = vgcs_vbs_find_lchan(bts, &gc);
if (!req.target_lchan) {
cause = GSM0808_CAUSE_INCORRECT_VALUE;
goto reject;
}
req.assign_for = ASSIGN_FOR_BSSMAP_REQ;
req.vgcs = true;
/* Copy timing advance. */
if (conn->lchan) {
req.target_lchan->activate.info.ta_known = conn->lchan->activate.info.ta_known;
req.target_lchan->activate.info.ta = conn->lchan->activate.info.ta;
}
/* Send reactivation on target lchan to prepare VGCS channel for assignment.
* See patent EP 1 858 275 A1. */
rsl_tx_chan_activ(req.target_lchan, RSL_ACT_TYPE_REACT | RSL_ACT_INTRA_NORM_ASS, 0);
return osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_ASSIGNMENT_START, &req);
}
bssmap_handle_ass_req_lcls(conn, &tp);
/* Currently we only support a limited subset of all
* possible channel types, such as multi-slot */
switch (ct.ch_indctr) {
case GSM0808_CHAN_DATA:
if (bssmap_handle_ass_req_ct_data(conn, &tp, &ct, &req, &cause) < 0)
goto reject;
break;
case GSM0808_CHAN_SPEECH:
if (bssmap_handle_ass_req_ct_speech(conn, conn_get_bts(conn), &tp, &ct, &req, &cause) < 0)
goto reject;
break;
case GSM0808_CHAN_SIGN:
if (bssmap_handle_ass_req_ct_sign(conn, &ct, &req, &cause) < 0)
goto reject;
break;
default:
cause = GSM0808_CAUSE_INVALID_MESSAGE_CONTENTS;
goto reject;
}
req.ch_indctr = ct.ch_indctr;
return osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_ASSIGNMENT_START, &req);
reject:
resp = gsm0808_create_assignment_failure(cause, NULL);
OSMO_ASSERT(resp);
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_ASSIGNMENT_FAILURE));
osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_TX_SCCP, resp);
return -1;
}
/* Handle Handover Request message, part of inter-BSC handover:
* The MSC opened a new SCCP connection and is asking this BSS to accept an inter-BSC incoming handover.
* If we accept, we'll send a Handover Request Acknowledge.
* This function is only called when the Handover Request is *not* included in the initial SCCP N-Connect message, but
* follows an "empty" N-Connect in a separate DT1 message.
*/
static int bssmap_handle_handover_request(struct gsm_subscriber_connection *conn, struct msgb *msg)
{
if (osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_A_INITIAL_USER_DATA, msg)) {
/* A Handover Request message should come in on a newly opened SCCP conn. Apparently the MSC has sent a
* Handover Request on an already busy SCCP conn, and naturally we cannot accept another subscriber
* here. This is unlikely to ever happen in practice. Respond in the only possible way: */
bsc_tx_bssmap_ho_failure(conn);
return -EINVAL;
}
return 0;
}
/* Handle Handover Command message, part of inter-BSC handover:
* This BSS sent a Handover Required message.
* The MSC contacts the remote BSS and receives from it an RR Handover Command; this BSSMAP Handover
* Command passes the RR Handover Command over to us and it's our job to forward to the MS.
*
* See 3GPP TS 48.008 §3.2.1.11
*/
static int bssmap_handle_handover_cmd(struct gsm_subscriber_connection *conn,
struct msgb *msg, unsigned int length)
{
struct tlv_parsed tp;
if (!conn->ho.fi) {
LOGPFSML(conn->fi, LOGL_ERROR,
"Received Handover Command, but no handover was requested\n");
/* Should we actually allow the MSC to make us handover without us having requested it
* first? Doesn't make any practical sense AFAICT. */
return -EINVAL;
}
if (osmo_bssap_tlv_parse(&tp, msg->l4h + 1, length - 1) < 0) {
LOGPFSML(conn->fi, LOGL_ERROR, "%s(): tlv_parse() failed\n", __func__);
return -1;
}
/* Check for channel type element, if its missing, immediately reject */
if (!TLVP_PRESENT(&tp, GSM0808_IE_LAYER_3_INFORMATION)) {
LOGPFSML(conn->fi, LOGL_ERROR,
"Received Handover Command,"
" but mandatory IE not present: Layer 3 Information\n");
goto reject;
}
/* Due to constness, need to declare this after tlv_parse(). */
struct ho_out_rx_bssmap_ho_command rx = {
.l3_info = TLVP_VAL(&tp, GSM0808_IE_LAYER_3_INFORMATION),
.l3_info_len = TLVP_LEN(&tp, GSM0808_IE_LAYER_3_INFORMATION),
};
osmo_fsm_inst_dispatch(conn->ho.fi, HO_OUT_EV_BSSMAP_HO_COMMAND, &rx);
return 0;
reject:
/* No "Handover Command Reject" message or similar is specified, so we cannot reply in case of
* failure. Or is there?? */
handover_end(conn, HO_RESULT_ERROR);
return -EINVAL;
}
/* Handle Confusion message, MSC indicating an error to us:
*
* See 3GPP TS 48.008 §3.2.1.45
*/
static int bssmap_handle_confusion(struct gsm_subscriber_connection *conn,
struct msgb *msg, unsigned int length)
{
struct tlv_parsed tp;
int diag_len;
enum gsm0808_cause cause;
enum gsm0808_cause_class cause_class;
struct gsm0808_diagnostics *diag;
if (osmo_bssap_tlv_parse(&tp, msg->l4h + 1, length - 1) < 0) {
LOGPFSML(conn->fi, LOGL_ERROR, "%s(): tlv_parse() failed\n", __func__);
return -1;
}
/* Check for the Cause and Diagnostic mandatory elements */
if (!TLVP_PRESENT(&tp, GSM0808_IE_CAUSE) || !TLVP_PRESENT(&tp, GSM0808_IE_DIAGNOSTIC)) {
LOGPFSML(conn->fi, LOGL_ERROR,
"Received BSSMAP Confusion message,"
" but either Cause or Diagnostic mandatory IE is not present: %s\n",
osmo_hexdump(msg->l4h, length));
return -EINVAL;
}
diag_len = TLVP_LEN(&tp, GSM0808_IE_DIAGNOSTIC);
if (diag_len < 5) {
LOGPFSML(conn->fi, LOGL_ERROR,
"Received BSSMAP Confusion message with short Diagnostic length: %d (expected > 5)\n",
diag_len);
return -EINVAL;
}
cause = gsm0808_get_cause(&tp);
cause_class = gsm0808_cause_class(cause);
diag = (struct gsm0808_diagnostics *)TLVP_VAL(&tp, GSM0808_IE_DIAGNOSTIC);
LOGPFSML(conn->fi, LOGL_ERROR,
"Received BSSMAP Confusion: class 0x%x (%s), cause 0x%x (%s), "
"error octet %d (%s), error bit %d (%s), original message: %s\n",
cause_class, gsm0808_cause_class_name(cause_class),
cause, gsm0808_cause_name(cause),
diag->error_pointer_octet,
gsm0808_diagnostics_octet_location_str(diag->error_pointer_octet),
diag->error_pointer_bit,
gsm0808_diagnostics_bit_location_str(diag->error_pointer_bit),
osmo_hexdump(diag->msg, diag_len-2));
return 0;
}
/* Common ID; 3GPP TS 48.008 3.2.1.68 */
static int bssmap_handle_common_id(struct gsm_subscriber_connection *conn,
struct msgb *msg, unsigned int length)
{
struct tlv_parsed tp;
if (osmo_bssap_tlv_parse(&tp, msg->l4h + 1, length - 1) < 0) {
LOGPFSML(conn->fi, LOGL_ERROR, "%s(): tlv_parse() failed\n", __func__);
return -1;
}
/* Check for the mandatory elements */
if (!TLVP_PRESENT(&tp, GSM0808_IE_IMSI)) {
LOGPFSML(conn->fi, LOGL_ERROR,
"CommonID: missing mandatory IMSI IE: %s\n",
osmo_hexdump(msg->l4h, length));
return -EINVAL;
}
osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_A_COMMON_ID_IND, &tp);
return 0;
}
/* Handle (VGCS) UPLINK REQUEST ACKNOWLEDGE:
*
* See 3GPP TS 48.008 §3.2.1.58
*/
static int bssmap_handle_uplink_rqst_acknowledge(struct gsm_subscriber_connection *conn,
struct msgb *msg, unsigned int length)
{
struct tlv_parsed tp;
if (osmo_bssap_tlv_parse(&tp, msg->l4h + 1, length - 1) < 0) {
LOGPFSML(conn->fi, LOGL_ERROR, "%s(): tlv_parse() failed\n", __func__);
return -1;
}
if (conn->vgcs_call.fi)
osmo_fsm_inst_dispatch(conn->vgcs_call.fi, VGCS_EV_MSC_ACK, NULL);
return 0;
}
/* Handle (VGCS) UPLINK REJECT COMMAND message.
*
* See 3GPP TS 48.008 §3.2.1.61
*/
static int bssmap_handle_uplink_reject_cmd(struct gsm_subscriber_connection *conn,
struct msgb *msg, unsigned int length)
{
struct tlv_parsed tp;
if (osmo_bssap_tlv_parse(&tp, msg->l4h + 1, length - 1) < 0) {
LOGPFSML(conn->fi, LOGL_ERROR, "%s(): tlv_parse() failed\n", __func__);
return -1;
}
if (conn->vgcs_call.fi)
osmo_fsm_inst_dispatch(conn->vgcs_call.fi, VGCS_EV_MSC_REJECT, NULL);
return 0;
}
/* Handle (VGCS) UPLINK RELEASE COMMAND message, MSC indicating an error to us:
*
* See 3GPP TS 48.008 §3.2.1.62
*/
static int bssmap_handle_uplink_release_cmd(struct gsm_subscriber_connection *conn,
struct msgb *msg, unsigned int length)
{
struct tlv_parsed tp;
if (osmo_bssap_tlv_parse(&tp, msg->l4h + 1, length - 1) < 0) {
LOGPFSML(conn->fi, LOGL_ERROR, "%s(): tlv_parse() failed\n", __func__);
return -1;
}
if (conn->vgcs_call.fi)
osmo_fsm_inst_dispatch(conn->vgcs_call.fi, VGCS_EV_MSC_RELEASE, NULL);
return 0;
}
/* Handle (VGCS) UPLINK SEIZED COMMAND message:
*
* See 3GPP TS 48.008 §3.2.1.63
*/
static int bssmap_handle_uplink_seized_cmd(struct gsm_subscriber_connection *conn,
struct msgb *msg, unsigned int length)
{
struct tlv_parsed tp;
if (osmo_bssap_tlv_parse(&tp, msg->l4h + 1, length - 1) < 0) {
LOGPFSML(conn->fi, LOGL_ERROR, "%s(): tlv_parse() failed\n", __func__);
return -1;
}
if (conn->vgcs_call.fi)
osmo_fsm_inst_dispatch(conn->vgcs_call.fi, VGCS_EV_MSC_SEIZE, NULL);
return 0;
}
/* Handle VGCS/VBS ADDITIONAL INFO message:
*
* See 3GPP TS 48.008 §3.2.1.78
*/
static int bssmap_handle_vgcs_addl_info(struct gsm_subscriber_connection *conn,
struct msgb *msg, unsigned int length)
{
struct tlv_parsed tp;
if (osmo_bssap_tlv_parse(&tp, msg->l4h + 1, length - 1) < 0) {
LOGPFSML(conn->fi, LOGL_ERROR, "%s(): tlv_parse() failed\n", __func__);
return -1;
}
LOGPFSML(conn->fi, LOGL_ERROR, "VGCS ADDITIONAL INFO is not supported.\n");
return 0;
}
static int bssmap_rcvmsg_udt(struct bsc_msc_data *msc,
struct msgb *msg, unsigned int length)
{
int ret = 0;
struct rate_ctr *ctrs = msc->msc_ctrs->ctr;
if (length < 1) {
LOGP(DMSC, LOGL_ERROR, "Not enough room: %d\n", length);
return -1;
}
LOGP(DMSC, LOGL_INFO, "Rx MSC UDT BSSMAP %s\n",
gsm0808_bssmap_name(msg->l4h[0]));
switch (msg->l4h[0]) {
case BSS_MAP_MSG_RESET_ACKNOWLEDGE:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_UDT_RESET_ACKNOWLEDGE]);
ret = bssmap_handle_reset_ack(msc, msg, length);
break;
case BSS_MAP_MSG_RESET:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_UDT_RESET]);
ret = bssmap_handle_reset(msc, msg, length);
break;
case BSS_MAP_MSG_PAGING:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_UDT_PAGING]);
ret = bssmap_handle_paging(msc, msg, length);
break;
default:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_UDT_UNKNOWN]);
LOGP(DMSC, LOGL_NOTICE, "Received unimplemented BSSMAP UDT %s\n",
gsm0808_bssmap_name(msg->l4h[0]));
break;
}
return ret;
}
static int bssmap_rcvmsg_dt1(struct gsm_subscriber_connection *conn,
struct msgb *msg, unsigned int length)
{
int ret = 0;
struct rate_ctr *ctrs = conn->sccp.msc->msc_ctrs->ctr;
if (length < 1) {
LOGP(DMSC, LOGL_ERROR, "Not enough room: %d\n", length);
return -1;
}
LOGP(DMSC, LOGL_INFO, "Rx MSC DT1 BSSMAP %s\n",
gsm0808_bssmap_name(msg->l4h[0]));
switch (msg->l4h[0]) {
case BSS_MAP_MSG_CLEAR_CMD:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_CLEAR_CMD]);
ret = bssmap_handle_clear_cmd(conn, msg, length);
break;
case BSS_MAP_MSG_CIPHER_MODE_CMD:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_CIPHER_MODE_CMD]);
ret = bssmap_handle_cipher_mode(conn, msg, length);
break;
case BSS_MAP_MSG_ASSIGNMENT_RQST:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_ASSIGNMENT_RQST]);
ret = bssmap_handle_assignm_req(conn, msg, length);
break;
case BSS_MAP_MSG_LCLS_CONNECT_CTRL:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_LCLS_CONNECT_CTRL]);
ret = bssmap_handle_lcls_connect_ctrl(conn, msg, length);
break;
case BSS_MAP_MSG_HANDOVER_RQST:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_HANDOVER_RQST]);
ret = bssmap_handle_handover_request(conn, msg);
break;
case BSS_MAP_MSG_HANDOVER_CMD:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_HANDOVER_CMD]);
ret = bssmap_handle_handover_cmd(conn, msg, length);
break;
case BSS_MAP_MSG_CLASSMARK_RQST:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_CLASSMARK_RQST]);
ret = gsm48_send_rr_classmark_enquiry(conn->lchan);
break;
case BSS_MAP_MSG_CONFUSION:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_CONFUSION]);
ret = bssmap_handle_confusion(conn, msg, length);
break;
case BSS_MAP_MSG_COMMON_ID:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_COMMON_ID]);
ret = bssmap_handle_common_id(conn, msg, length);
break;
case BSS_MAP_MSG_PERFORM_LOCATION_RQST:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_PERFORM_LOCATION_REQUEST]);
lcs_loc_req_start(conn, msg);
ret = 0;
break;
case BSS_MAP_MSG_PERFORM_LOCATION_ABORT:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_PERFORM_LOCATION_ABORT]);
if (conn->lcs.loc_req) {
ret = osmo_fsm_inst_dispatch(conn->lcs.loc_req->fi, LCS_LOC_REQ_EV_RX_A_PERFORM_LOCATION_ABORT,
msg);
} else {
LOGP(DMSC, LOGL_ERROR, "Rx BSSMAP Perform Location Abort without ongoing Location Request\n");
ret = 0;
}
break;
case BSS_MAP_MSG_UPLINK_RQST_ACKNOWLEDGE:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_UPLINK_RQST_ACKNOWLEDGE]);
ret = bssmap_handle_uplink_rqst_acknowledge(conn, msg, length);
break;
case BSS_MAP_MSG_UPLINK_REJECT_CMD:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_UPLINK_REJECT_CMD]);
ret = bssmap_handle_uplink_reject_cmd(conn, msg, length);
break;
case BSS_MAP_MSG_UPLINK_RELEASE_CMD:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_UPLINK_RELEASE_CMD]);
ret = bssmap_handle_uplink_release_cmd(conn, msg, length);
break;
case BSS_MAP_MSG_UPLINK_SEIZED_CMD:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_UPLINK_SEIZED_CMD]);
ret = bssmap_handle_uplink_seized_cmd(conn, msg, length);
break;
case BSS_MAP_MSG_VGCS_ADDL_INFO:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_VGCS_ADDL_INFO]);
ret = bssmap_handle_vgcs_addl_info(conn, msg, length);
break;
default:
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_UNKNOWN]);
LOGP(DMSC, LOGL_NOTICE, "Unimplemented msg type: %s\n",
gsm0808_bssmap_name(msg->l4h[0]));
break;
}
return ret;
}
static int dtap_rcvmsg(struct gsm_subscriber_connection *conn,
struct msgb *msg, unsigned int length)
{
struct dtap_header *header;
struct msgb *gsm48;
uint8_t *data;
int dtap_rc;
struct rate_ctr *ctrs;
LOGP(DMSC, LOGL_DEBUG, "Rx MSC DTAP: %s\n",
osmo_hexdump(msg->l3h, length));
if (!conn) {
LOGP(DMSC, LOGL_ERROR, "No subscriber connection available\n");
return -1;
}
ctrs = conn->sccp.msc->msc_ctrs->ctr;
header = (struct dtap_header *) msg->l3h;
if (sizeof(*header) >= length) {
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_DTAP_ERROR]);
LOGP(DMSC, LOGL_ERROR, "The DTAP header does not fit. Wanted: %zu got: %u, hex: %s\n",
sizeof(*header), length, osmo_hexdump(msg->l3h, length));
return -1;
}
if (header->length > length - sizeof(*header)) {
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_DTAP_ERROR]);
LOGP(DMSC, LOGL_ERROR, "The DTAP l4 information does not fit. Wanted: %u got: %zu, hex: %s\n",
header->length, length - sizeof(*header), osmo_hexdump(msg->l3h, length));
return -1;
}
rate_ctr_inc(&ctrs[MSC_CTR_BSSMAP_RX_DT1_DTAP]);
LOGP(DMSC, LOGL_INFO, "Rx MSC DTAP, SAPI: %s CHAN: %u\n", gsm0406_dlci_sapi_name(header->dlci_sapi), header->dlci_cc);
/* forward the data */
gsm48 = gsm48_msgb_alloc_name("GSM 04.08 DTAP RCV");
if (!gsm48) {
LOGP(DMSC, LOGL_ERROR, "Allocation of the message failed.\n");
return -1;
}
gsm48->l3h = gsm48->data;
data = msgb_put(gsm48, length - sizeof(*header));
memcpy(data, msg->l3h + sizeof(*header), length - sizeof(*header));
/* pass it to the filter for extra actions */
bsc_scan_msc_msg(conn, gsm48);
/* convert DLCI to RSL link ID, store in msg->cb */
OBSC_LINKID_CB(gsm48) = DLCI2RSL_LINK_ID(header->link_id);
if (conn->vgcs_call.fi)
dtap_rc = osmo_fsm_inst_dispatch(conn->vgcs_call.fi, VGCS_EV_MSC_DTAP, gsm48);
else
dtap_rc = osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_MT_DTAP, gsm48);
return dtap_rc;
}
int bsc_handle_udt(struct bsc_msc_data *msc,
struct msgb *msgb, unsigned int length)
{
struct bssmap_header *bs;
LOGP(DMSC, LOGL_DEBUG, "Rx MSC UDT: %s\n",
osmo_hexdump(msgb->l3h, length));
if (length < sizeof(*bs)) {
LOGP(DMSC, LOGL_ERROR, "The header is too short.\n");
return -1;
}
bs = (struct bssmap_header *) msgb->l3h;
if (bs->length < length - sizeof(*bs))
return -1;
switch (bs->type) {
case BSSAP_MSG_BSS_MANAGEMENT:
msgb->l4h = &msgb->l3h[sizeof(*bs)];
bssmap_rcvmsg_udt(msc, msgb, length - sizeof(*bs));
break;
default:
LOGP(DMSC, LOGL_NOTICE, "Unimplemented msg type: %s\n",
gsm0808_bssmap_name(bs->type));
}
return 0;
}
/* Extract and verify the length information from the BSSMAP header. */
static unsigned int bssmap_msg_len(struct msgb *msg, unsigned int length,
const struct gsm_subscriber_connection *conn)
{
unsigned int expected_len;
unsigned int calculated_len;
struct bssmap_header *bssmap_header;
bssmap_header = (struct bssmap_header *)msg->l3h;
calculated_len = length - sizeof(struct bssmap_header);
expected_len = bssmap_header->length;
/* In case of contradictory length information, decide for the
* shorter length */
if (calculated_len > expected_len) {
LOGPFSML(conn->fi, LOGL_NOTICE,
"BSSMAP message contains extra data, expected %u bytes, got %u bytes, truncated\n",
expected_len, calculated_len);
return expected_len;
} else if (calculated_len < expected_len) {
LOGPFSML(conn->fi, LOGL_NOTICE,
"Short BSSMAP message, expected %u bytes, got %u bytes\n",
expected_len, calculated_len);
return calculated_len;
}
return expected_len;
}
int bsc_handle_dt(struct gsm_subscriber_connection *conn,
struct msgb *msg, unsigned int len)
{
log_set_context(LOG_CTX_BSC_SUBSCR, conn->bsub);
if (len < sizeof(struct bssmap_header)) {
LOGP(DMSC, LOGL_ERROR, "The header is too short.\n");
}
switch (msg->l3h[0]) {
case BSSAP_MSG_BSS_MANAGEMENT:
msg->l4h = &msg->l3h[sizeof(struct bssmap_header)];
bssmap_rcvmsg_dt1(conn, msg, bssmap_msg_len(msg, len, conn));
break;
case BSSAP_MSG_DTAP:
dtap_rcvmsg(conn, msg, len);
break;
default:
LOGP(DMSC, LOGL_NOTICE, "Unimplemented BSSAP msg type: %s\n",
gsm0808_bssap_name(msg->l3h[0]));
}
log_set_context(LOG_CTX_BSC_SUBSCR, NULL);
return -1;
}
int bsc_tx_bssmap_ho_required(struct gsm_lchan *lchan, const struct gsm0808_cell_id_list2 *target_cells)
{
int rc;
struct msgb *msg;
struct gsm_subscriber_connection *conn = lchan->conn;
struct gsm0808_handover_required params = {
.cause = GSM0808_CAUSE_BETTER_CELL,
.cil = *target_cells,
.current_channel_type_1_present = true,
.current_channel_type_1 = gsm0808_current_channel_type_1(lchan->type),
};
/* Even if fast_return is now allowed locally, we may still want to
* signal the Last EUTRAN PLMN Id to the new cell, since destination
* config may differ and allow fast return */
if (conn->fast_return.last_eutran_plmn_valid) {
params.old_bss_to_new_bss_info_present = true;
params.old_bss_to_new_bss_info.last_eutran_plmn_id_present = true;
params.old_bss_to_new_bss_info.last_eutran_plmn_id = conn->fast_return.last_eutran_plmn;
}
switch (lchan->type) {
case GSM_LCHAN_TCH_F:
case GSM_LCHAN_TCH_H:
params.speech_version_used_present = true;
params.speech_version_used = gsm0808_permitted_speech(lchan->type,
lchan->current_ch_mode_rate.chan_mode);
if (!params.speech_version_used) {
LOG_HO(lchan->conn, LOGL_ERROR, "Cannot encode Speech Version (Used)"
" for BSSMAP Handover Required message\n");
return -EINVAL;
}
break;
default:
break;
}
msg = gsm0808_create_handover_required(&params);
if (!msg) {
LOG_HO(conn, LOGL_ERROR, "Cannot compose BSSMAP Handover Required message\n");
return -EINVAL;
}
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_HANDOVER_REQUIRED));
rc = gscon_sigtran_send(conn, msg);
if (rc) {
LOG_HO(conn, LOGL_ERROR, "Cannot send BSSMAP Handover Required message\n");
return rc;
}
return 0;
}
/* Inter-BSC MT HO, new BSS has allocated a channel and sends the RR Handover Command via MSC to the old
* BSS, encapsulated in a BSSMAP Handover Request Acknowledge. */
int bsc_tx_bssmap_ho_request_ack(struct gsm_subscriber_connection *conn, struct msgb *rr_ho_command)
{
struct msgb *msg;
struct gsm_lchan *new_lchan = conn->ho.new_lchan;
struct sockaddr_storage ss;
struct gsm0808_handover_request_ack params = {
.l3_info = rr_ho_command->data,
.l3_info_len = rr_ho_command->len,
.chosen_channel_present = true,
.chosen_channel = gsm0808_chosen_channel(new_lchan->type, new_lchan->current_ch_mode_rate.chan_mode),
.chosen_encr_alg = ALG_A5_NR_TO_BSSAP(new_lchan->encr.alg_a5_n),
.chosen_speech_version = gsm0808_permitted_speech(new_lchan->type,
new_lchan->current_ch_mode_rate.chan_mode),
};
if (gscon_is_aoip(conn) && bsc_chan_ind_requires_rtp_stream(new_lchan->activate.info.ch_indctr)) {
struct osmo_sockaddr_str to_msc_rtp;
const struct mgcp_conn_peer *rtp_info = osmo_mgcpc_ep_ci_get_rtp_info(conn->user_plane.mgw_endpoint_ci_msc);
int rc;
int perm_spch;
if (!rtp_info) {
LOG_HO(conn, LOGL_ERROR,
"Handover Request Acknowledge: no RTP address known to send as"
" AoIP Transport Layer Address\n");
return -EINVAL;
}
if (osmo_sockaddr_str_from_str(&to_msc_rtp, rtp_info->addr, rtp_info->port)) {
LOG_HO(conn, LOGL_ERROR, "Handover Request Acknowledge: cannot encode AoIP Transport Layer\n");
return -EINVAL;
}
if (osmo_sockaddr_str_to_sockaddr(&to_msc_rtp, &ss)) {
LOG_HO(conn, LOGL_ERROR, "Handover Request Acknowledge: cannot encode AoIP Transport Layer\n");
return -EINVAL;
}
params.aoip_transport_layer = &ss;
/* speech_codec_chosen */
perm_spch = gsm0808_permitted_speech(new_lchan->type, new_lchan->current_ch_mode_rate.chan_mode);
params.speech_codec_chosen_present = true;
rc = gsm0808_speech_codec_from_chan_type(&params.speech_codec_chosen, perm_spch);
if (rc) {
LOG_HO(conn, LOGL_ERROR, "Unable to compose Speech Codec (Chosen)\n");
return -EINVAL;
}
/* Codec list (BSS Supported) */
params.more_items = true;
gen_bss_supported_codec_list(&params.codec_list_bss_supported, conn->sccp.msc, new_lchan->ts->trx->bts);
}
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_HANDOVER_RQST_ACKNOWLEDGE));
LOG_HO(conn, LOGL_DEBUG, "Sending BSSMAP Handover Request Acknowledge\n");
msg = gsm0808_create_handover_request_ack2(&params);
msgb_free(rr_ho_command);
if (!msg)
return -ENOMEM;
return osmo_bsc_sigtran_send(conn, msg);
}
int bsc_tx_bssmap_ho_detect(struct gsm_subscriber_connection *conn)
{
struct msgb *msg;
msg = gsm0808_create_handover_detect();
if (!msg)
return -ENOMEM;
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_HANDOVER_DETECT));
return osmo_bsc_sigtran_send(conn, msg);
}
enum handover_result bsc_tx_bssmap_ho_complete(struct gsm_subscriber_connection *conn,
struct gsm_lchan *lchan)
{
int rc;
struct msgb *msg;
struct handover *ho = &conn->ho;
enum gsm0808_lcls_status lcls_status = lcls_get_status(conn);
struct gsm0808_handover_complete params = {
.chosen_encr_alg_present = true,
.chosen_encr_alg = ALG_A5_NR_TO_BSSAP(lchan->encr.alg_a5_n),
.chosen_channel_present = true,
.chosen_channel = gsm0808_chosen_channel(lchan->type, lchan->current_ch_mode_rate.chan_mode),
.lcls_bss_status_present = (lcls_status != 0xff),
.lcls_bss_status = lcls_status,
};
/* speech_codec_chosen */
if (bsc_chan_ind_requires_rtp_stream(ho->new_lchan->activate.info.ch_indctr) && gscon_is_aoip(conn)) {
int perm_spch = gsm0808_permitted_speech(lchan->type, lchan->current_ch_mode_rate.chan_mode);
params.speech_codec_chosen_present = true;
rc = gsm0808_speech_codec_from_chan_type(&params.speech_codec_chosen, perm_spch);
if (rc) {
LOG_HO(conn, LOGL_ERROR, "Unable to compose Speech Codec (Chosen)\n");
return HO_RESULT_ERROR;
}
}
msg = gsm0808_create_handover_complete(&params);
if (!msg) {
LOG_HO(conn, LOGL_ERROR, "Unable to compose BSSMAP Handover Complete message\n");
return HO_RESULT_ERROR;
}
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_HANDOVER_COMPLETE));
rc = osmo_bsc_sigtran_send(conn, msg);
if (rc) {
LOG_HO(conn, LOGL_ERROR, "Cannot send BSSMAP Handover Complete message\n");
return HO_RESULT_ERROR;
}
return HO_RESULT_OK;
}
void bsc_tx_bssmap_ho_failure(struct gsm_subscriber_connection *conn)
{
int rc;
struct msgb *msg;
struct gsm0808_handover_failure params = {};
msg = gsm0808_create_handover_failure(&params);
if (!msg) {
LOG_HO(conn, LOGL_ERROR, "Unable to compose BSSMAP Handover Failure message\n");
return;
}
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_HANDOVER_FAILURE));
rc = osmo_bsc_sigtran_send(conn, msg);
if (rc)
LOG_HO(conn, LOGL_ERROR, "Cannot send BSSMAP Handover Failure message (rc=%d %s)\n",
rc, strerror(-rc));
}
/* Send SETUP ACKNOWLEDGE to MSC. */
void bsc_tx_setup_ack(struct gsm_subscriber_connection *conn, struct gsm0808_vgcs_feature_flags *ff)
{
struct msgb *resp;
struct gsm0808_vgcs_vbs_setup_ack sa = {};
if (ff) {
sa.vgcs_feature_flags_present = true;
sa.flags = *ff;
}
resp = gsm0808_create_vgcs_vbs_setup_ack(&sa);
OSMO_ASSERT(resp);
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_VGCS_VBS_SETUP_ACK));
osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_TX_SCCP, resp);
}
/* Send SETUP REFUSE to MSC. */
void bsc_tx_setup_refuse(struct gsm_subscriber_connection *conn, uint8_t cause)
{
struct msgb *resp;
resp = gsm0808_create_vgcs_vbs_setup_refuse(cause);
OSMO_ASSERT(resp);
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_VGCS_VBS_SETUP_REFUSE));
osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_TX_SCCP, resp);
}
/* Send ASSIGNMENT FAILURE to MSC. */
void bsc_tx_vgcs_vbs_assignment_fail(struct gsm_subscriber_connection *conn, uint8_t cause)
{
struct msgb *resp;
struct gsm0808_vgcs_vbs_assign_fail af = {
.cause = cause,
};
resp = gsm0808_create_vgcs_vbs_assign_fail(&af);
OSMO_ASSERT(resp);
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_VGCS_VBS_ASSIGN_FAIL));
osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_TX_SCCP, resp);
}
/* Send ASSIGNMENT RESULT to MSC. */
void bsc_tx_vgcs_vbs_assignment_result(struct gsm_subscriber_connection *conn, struct gsm0808_channel_type *ct,
struct gsm0808_cell_id *ci, uint32_t call_id)
{
struct gsm_lchan *lchan = conn->lchan;
struct msgb *resp;
struct gsm0808_vgcs_vbs_assign_res ar = {
.channel_type = *ct,
.cell_identifier = *ci,
};
int perm_spch;
uint8_t osmux_cid;
/* Chosen Channel */
ar.chosen_channel = gsm0808_chosen_channel(lchan->type, lchan->current_ch_mode_rate.chan_mode);
if (!ar.chosen_channel) {
LOGP(DMSC, LOGL_ERROR, "Unable to compose Chosen Channel for mode=%s type=%s",
get_value_string(gsm48_chan_mode_names, lchan->current_ch_mode_rate.chan_mode),
gsm_chan_t_name(lchan->type));
bsc_tx_vgcs_vbs_assignment_fail(conn, GSM0808_CAUSE_EQUIPMENT_FAILURE);
return;
}
ar.chosen_channel_present = true;
/* Generate RTP related fields. */
if (gscon_is_aoip(conn)) {
/* AoIP Transport Layer Address (BSS) */
if (!osmo_mgcpc_ep_ci_get_crcx_info_to_sockaddr(conn->user_plane.mgw_endpoint_ci_msc,
&ar.aoip_transport_layer)) {
LOGP(DMSC, LOGL_ERROR, "Unable to compose RTP address of MGW -> MSC");
bsc_tx_vgcs_vbs_assignment_fail(conn, GSM0808_CAUSE_EQUIPMENT_FAILURE);
return;
}
ar.aoip_transport_layer_present = true;
/* Call Identifier */
ar.call_id = call_id;
ar.call_id_present = true;
/* Osmux */
if (conn->assignment.req.use_osmux) {
if (!osmo_mgcpc_ep_ci_get_crcx_info_to_osmux_cid(conn->user_plane.mgw_endpoint_ci_msc,
&osmux_cid)) {
LOGP(DMSC, LOGL_ERROR, "Unable to compose Osmux CID of MGW -> MSC");
bsc_tx_vgcs_vbs_assignment_fail(conn, GSM0808_CAUSE_EQUIPMENT_FAILURE);
return;
}
}
/* Extrapolate speech codec from speech mode */
perm_spch = gsm0808_permitted_speech(lchan->type, lchan->current_ch_mode_rate.chan_mode);
gsm0808_speech_codec_from_chan_type(&ar.codec_msc_chosen, perm_spch);
ar.codec_msc_chosen.cfg = conn->lchan->current_ch_mode_rate.s15_s0;
ar.codec_present = true;
}
resp = gsm0808_create_vgcs_vbs_assign_res(&ar);
OSMO_ASSERT(resp);
if (conn->assignment.req.use_osmux)
bssap_extend_osmux(resp, osmux_cid);
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_VGCS_VBS_ASSIGN_RESULT));
osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_TX_SCCP, resp);
}
/* Send UPLINK REQUEST to MSC. */
void bsc_tx_uplink_req(struct gsm_subscriber_connection *conn)
{
struct msgb *resp;
struct gsm0808_uplink_request ur = {};
resp = gsm0808_create_uplink_request(&ur);
OSMO_ASSERT(resp);
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_UPLINK_RQST));
osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_TX_SCCP, resp);
}
/* Send UPLINK REQUEST CONFIRMATION to MSC. */
void bsc_tx_uplink_req_conf(struct gsm_subscriber_connection *conn, struct gsm0808_cell_id *ci, uint8_t *l3_info,
uint8_t length)
{
struct msgb *resp;
struct gsm0808_uplink_request_cnf ur = {
.cell_identifier = *ci,
};
OSMO_ASSERT(length <= LAYER_3_INFORMATION_MAXLEN);
if (length) {
memcpy(ur.l3.l3, l3_info, length);
ur.l3.l3_len = length;
}
resp = gsm0808_create_uplink_request_cnf(&ur);
OSMO_ASSERT(resp);
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_UPLINK_RQST_CONFIRMATION));
osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_TX_SCCP, resp);
}
/* Send UPLINK APPLICATION DATA to MSC. */
void bsc_tx_uplink_app_data(struct gsm_subscriber_connection *conn, struct gsm0808_cell_id *ci, uint8_t *l3_info,
uint8_t length)
{
struct msgb *resp;
struct gsm0808_uplink_app_data ad = {
.cell_identifier = *ci,
};
OSMO_ASSERT(length <= LAYER_3_INFORMATION_MAXLEN);
memcpy(ad.l3.l3, l3_info, length);
ad.l3.l3_len = length;
resp = gsm0808_create_uplink_app_data(&ad);
OSMO_ASSERT(resp);
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_UPLINK_APP_DATA));
osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_TX_SCCP, resp);
}
/* Send UPLINK RELEASE INDICATION to MSC. */
void bsc_tx_uplink_release_ind(struct gsm_subscriber_connection *conn, uint8_t cause)
{
struct msgb *resp;
struct gsm0808_uplink_release_ind ri = {
.cause = cause,
};
resp = gsm0808_create_uplink_release_ind(&ri);
OSMO_ASSERT(resp);
rate_ctr_inc(rate_ctr_group_get_ctr(conn->sccp.msc->msc_ctrs, MSC_CTR_BSSMAP_TX_DT1_UPLINK_RELEASE_INDICATION));
osmo_fsm_inst_dispatch(conn->fi, GSCON_EV_TX_SCCP, resp);
}
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