748 lines
21 KiB
C
748 lines
21 KiB
C
/* GSM 08.08 like API for OpenBSC. The bridge from MSC to BSC */
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/* (C) 2010-2011 by Holger Hans Peter Freyther
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* (C) 2010-2011 by On-Waves
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* (C) 2009,2017 by Harald Welte <laforge@gnumonks.org>
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*
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* All Rights Reserved
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU Affero General Public License as published by
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* the Free Software Foundation; either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU Affero General Public License for more details.
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*
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* You should have received a copy of the GNU Affero General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*
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*/
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#include <osmocom/bsc/bsc_api.h>
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#include <osmocom/bsc/bsc_rll.h>
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#include <osmocom/bsc/gsm_data.h>
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#include <osmocom/bsc/signal.h>
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#include <osmocom/bsc/abis_rsl.h>
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#include <osmocom/bsc/chan_alloc.h>
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#include <osmocom/bsc/handover.h>
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#include <osmocom/bsc/debug.h>
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#include <osmocom/bsc/gsm_04_08_utils.h>
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#include <osmocom/bsc/bsc_subscriber.h>
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#include <osmocom/bsc/penalty_timers.h>
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#include <osmocom/bsc/osmo_bsc_sigtran.h>
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#include <osmocom/gsm/protocol/gsm_08_08.h>
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#include <osmocom/gsm/gsm48.h>
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#include <osmocom/core/talloc.h>
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#define GSM0808_T10_VALUE 6, 0
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#define HO_DTAP_CACHE_MSGB_CB_LINK_ID 0
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#define HO_DTAP_CACHE_MSGB_CB_ALLOW_SACCH 1
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static void rll_ind_cb(struct gsm_lchan *, uint8_t, void *, enum bsc_rllr_ind);
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static void handle_release(struct gsm_subscriber_connection *conn, struct gsm_lchan *lchan);
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static void handle_chan_ack(struct gsm_subscriber_connection *conn, struct gsm_lchan *lchan);
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static void handle_chan_nack(struct gsm_subscriber_connection *conn, struct gsm_lchan *lchan);
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/*
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* Start a new assignment and make sure that it is completed within T10 either
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* positively, negatively or by the timeout.
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*
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* 1.) allocate a new lchan
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* 2.) copy the encryption key and other data from the
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* old to the new channel.
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* 3.) RSL Channel Activate this channel and wait
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*
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* -> Signal handler for the LCHAN
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* 4.) Send GSM 04.08 assignment command to the MS
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*
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* -> Assignment Complete/Assignment Failure
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* 5.) Release the SDCCH, continue signalling on the new link
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*/
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static int handle_new_assignment(struct gsm_subscriber_connection *conn, int chan_mode, int full_rate)
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{
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struct gsm_lchan *new_lchan;
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enum gsm_chan_t chan_type;
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chan_type = full_rate ? GSM_LCHAN_TCH_F : GSM_LCHAN_TCH_H;
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new_lchan = lchan_alloc(conn_get_bts(conn), chan_type, 0);
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if (!new_lchan) {
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LOGP(DMSC, LOGL_NOTICE, "%s No free channel for %s\n",
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bsc_subscr_name(conn->bsub), gsm_lchant_name(chan_type));
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return -1;
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}
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/* check if we are on TCH/F and requested TCH/H, but got TCH/F */
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if (conn->lchan->type == new_lchan->type
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&& chan_type != new_lchan->type) {
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LOGPLCHAN(conn->lchan, DHO, LOGL_NOTICE,
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"-> %s Will not re-assign to identical channel type, %s was requested\n",
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gsm_lchan_name(new_lchan), gsm_lchant_name(chan_type));
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lchan_free(new_lchan);
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return -1;
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}
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/* copy old data to the new channel */
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memcpy(&new_lchan->encr, &conn->lchan->encr, sizeof(new_lchan->encr));
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new_lchan->ms_power = conn->lchan->ms_power;
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new_lchan->bs_power = conn->lchan->bs_power;
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new_lchan->rqd_ta = conn->lchan->rqd_ta;
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/* copy new data to it */
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new_lchan->tch_mode = chan_mode;
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new_lchan->rsl_cmode = (chan_mode == GSM48_CMODE_SIGN) ?
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RSL_CMOD_SPD_SIGN : RSL_CMOD_SPD_SPEECH;
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/* handle AMR correctly */
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if (chan_mode == GSM48_CMODE_SPEECH_AMR)
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bsc_mr_config(conn, new_lchan, full_rate);
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if (rsl_chan_activate_lchan(new_lchan, RSL_ACT_INTRA_NORM_ASS, 0) < 0) {
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LOGPLCHAN(new_lchan, DHO, LOGL_ERROR, "could not activate channel\n");
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lchan_free(new_lchan);
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return -1;
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}
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/* remember that we have the channel */
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conn->secondary_lchan = new_lchan;
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new_lchan->conn = conn;
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return 0;
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}
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static void ho_dtap_cache_add(struct gsm_subscriber_connection *conn, struct msgb *msg,
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int link_id, bool allow_sacch)
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{
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if (conn->ho_dtap_cache_len >= 23) {
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LOGP(DHO, LOGL_ERROR, "%s: Cannot cache more DTAP messages,"
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" already reached sane maximum of %u cached messages\n",
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bsc_subscr_name(conn->bsub), conn->ho_dtap_cache_len);
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msgb_free(msg);
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return;
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}
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conn->ho_dtap_cache_len ++;
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LOGP(DHO, LOGL_DEBUG, "%s: Caching DTAP message during ho/ass (%u)\n",
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bsc_subscr_name(conn->bsub), conn->ho_dtap_cache_len);
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msg->cb[HO_DTAP_CACHE_MSGB_CB_LINK_ID] = (unsigned long)link_id;
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msg->cb[HO_DTAP_CACHE_MSGB_CB_ALLOW_SACCH] = allow_sacch ? 1 : 0;
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msgb_enqueue(&conn->ho_dtap_cache, msg);
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}
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void ho_dtap_cache_flush(struct gsm_subscriber_connection *conn, int send)
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{
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struct msgb *msg;
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unsigned int flushed_count = 0;
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if (conn->secondary_lchan || conn->ho) {
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LOGP(DHO, LOGL_ERROR, "%s: Cannot send cached DTAP messages, handover/assignment is still ongoing\n",
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bsc_subscr_name(conn->bsub));
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send = 0;
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}
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while ((msg = msgb_dequeue(&conn->ho_dtap_cache))) {
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conn->ho_dtap_cache_len --;
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flushed_count ++;
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if (send) {
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int link_id = (int)msg->cb[HO_DTAP_CACHE_MSGB_CB_LINK_ID];
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bool allow_sacch = !!msg->cb[HO_DTAP_CACHE_MSGB_CB_ALLOW_SACCH];
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LOGP(DHO, LOGL_DEBUG, "%s: Sending cached DTAP message after handover/assignment (%u/%u)\n",
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bsc_subscr_name(conn->bsub), flushed_count, conn->ho_dtap_cache_len);
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gsm0808_submit_dtap(conn, msg, link_id, allow_sacch);
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} else
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msgb_free(msg);
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}
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}
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/*! \brief process incoming 08.08 DTAP from MSC (send via BTS to MS) */
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int gsm0808_submit_dtap(struct gsm_subscriber_connection *conn,
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struct msgb *msg, int link_id, int allow_sacch)
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{
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uint8_t sapi;
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if (!conn->lchan) {
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LOGP(DMSC, LOGL_ERROR,
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"%s Called submit dtap without an lchan.\n",
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bsc_subscr_name(conn->bsub));
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msgb_free(msg);
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return -1;
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}
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/* buffer message during assignment / handover */
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if (conn->secondary_lchan || conn->ho) {
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ho_dtap_cache_add(conn, msg, link_id, !! allow_sacch);
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return 0;
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}
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sapi = link_id & 0x7;
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msg->lchan = conn->lchan;
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msg->dst = msg->lchan->ts->trx->rsl_link;
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/* If we are on a TCH and need to submit a SMS (on SAPI=3) we need to use the SACH */
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if (allow_sacch && sapi != 0) {
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if (conn->lchan->type == GSM_LCHAN_TCH_F || conn->lchan->type == GSM_LCHAN_TCH_H)
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link_id |= 0x40;
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}
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msg->l3h = msg->data;
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/* is requested SAPI already up? */
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if (conn->lchan->sapis[sapi] == LCHAN_SAPI_UNUSED) {
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/* Establish L2 for additional SAPI */
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OBSC_LINKID_CB(msg) = link_id;
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if (rll_establish(msg->lchan, sapi, rll_ind_cb, msg) != 0) {
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msgb_free(msg);
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bsc_sapi_n_reject(conn, link_id);
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return -1;
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}
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return 0;
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} else {
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/* Directly forward via RLL/RSL to BTS */
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return rsl_data_request(msg, link_id);
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}
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}
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/*
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* \brief Check if the given channel is compatible with the mode/fullrate
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*/
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static int chan_compat_with_mode(struct gsm_lchan *lchan, int chan_mode, int full_rate)
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{
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switch (chan_mode) {
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case GSM48_CMODE_SIGN:
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switch (lchan->type) {
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case GSM_LCHAN_TCH_F:
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case GSM_LCHAN_TCH_H:
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case GSM_LCHAN_SDCCH:
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return 1;
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default:
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return 0;
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}
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case GSM48_CMODE_SPEECH_V1:
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case GSM48_CMODE_SPEECH_AMR:
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case GSM48_CMODE_DATA_3k6:
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case GSM48_CMODE_DATA_6k0:
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/* these services can all run on TCH/H, but we may have
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* an explicit override by the 'full_rate' argument */
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switch (lchan->type) {
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case GSM_LCHAN_TCH_F:
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return full_rate ? 1 : 0;
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case GSM_LCHAN_TCH_H:
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return full_rate ? 0 : 1;
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default:
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return 0;
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}
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case GSM48_CMODE_DATA_12k0:
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case GSM48_CMODE_DATA_14k5:
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case GSM48_CMODE_SPEECH_EFR:
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/* these services all explicitly require a TCH/F */
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return (lchan->type == GSM_LCHAN_TCH_F) ? 1 : 0;
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default:
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return 0;
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}
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}
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/*! Send a GSM08.08 Assignment Request. Right now this does not contain the
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* audio codec type or the allowed rates for the config. In case the current
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* channel does not allow the selected mode a new one will be allocated.
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* \param[out] conn related subscriber connection
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* \param[in] chan_mode mode of the channel (see enum gsm48_chan_mode)
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* \param[in] full_rate select full rate or half rate channel
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* \returns 0 on success, 1 when no operation is neccessary, -1 on failure */
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int gsm0808_assign_req(struct gsm_subscriber_connection *conn, int chan_mode, int full_rate)
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{
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/* TODO: Add multirate configuration, make it work for more than audio. */
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if (!chan_compat_with_mode(conn->lchan, chan_mode, full_rate)) {
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if (handle_new_assignment(conn, chan_mode, full_rate) != 0)
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goto error;
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} else {
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/* Check if the channel is already in the requested mode, if
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* yes, we skip unnecessary channel mode modify operations. */
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if (conn->lchan->tch_mode == chan_mode)
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return 1;
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if (chan_mode == GSM48_CMODE_SPEECH_AMR)
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bsc_mr_config(conn, conn->lchan, full_rate);
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LOGPLCHAN(conn->lchan, DMSC, LOGL_NOTICE,
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"Sending ChanModify for speech: %s\n",
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get_value_string(gsm48_chan_mode_names, chan_mode));
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gsm48_lchan_modify(conn->lchan, chan_mode);
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}
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/* we expect the caller will manage T10 */
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return 0;
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error:
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bsc_assign_fail(conn, 0, NULL);
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return -1;
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}
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int gsm0808_page(struct gsm_bts *bts, unsigned int page_group, unsigned int mi_len,
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uint8_t *mi, int chan_type)
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{
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return rsl_paging_cmd(bts, page_group, mi_len, mi, chan_type, false);
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}
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static void handle_ass_compl(struct gsm_subscriber_connection *conn,
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struct msgb *msg)
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{
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struct gsm48_hdr *gh = msgb_l3(msg);
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enum gsm48_rr_cause cause;
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/* Expecting gsm48_hdr + cause value */
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if (msgb_l3len(msg) != sizeof(*gh) + 1) {
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LOGPLCHAN(msg->lchan, DRR, LOGL_ERROR,
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"RR Assignment Complete: length invalid: %u, expected %zu\n",
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msgb_l3len(msg), sizeof(*gh) + 1);
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return;
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}
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cause = gh->data[0];
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LOGPLCHAN(msg->lchan, DRR, LOGL_DEBUG, "ASSIGNMENT COMPLETE cause = %s\n",
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rr_cause_name(cause));
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if (conn->ho) {
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struct lchan_signal_data sig = {
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.lchan = msg->lchan,
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};
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osmo_signal_dispatch(SS_LCHAN, S_LCHAN_ASSIGNMENT_COMPL, &sig);
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/* FIXME: release old channel */
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/* send pending messages, if any */
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ho_dtap_cache_flush(conn, 1);
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return;
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}
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if (conn->secondary_lchan != msg->lchan) {
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LOGPLCHAN(msg->lchan, DRR, LOGL_ERROR,
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"RR Assignment Complete does not match conn's secondary lchan.\n");
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return;
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}
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lchan_release(conn->lchan, 0, RSL_REL_LOCAL_END);
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conn->lchan = conn->secondary_lchan;
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conn->secondary_lchan = NULL;
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/* send pending messages, if any */
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ho_dtap_cache_flush(conn, 1);
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if (is_ipaccess_bts(conn_get_bts(conn)) && conn->lchan->tch_mode != GSM48_CMODE_SIGN)
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rsl_ipacc_crcx(conn->lchan);
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bsc_assign_compl(conn, cause);
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}
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static void handle_ass_fail(struct gsm_subscriber_connection *conn,
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struct msgb *msg)
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{
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uint8_t *rr_failure;
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struct gsm48_hdr *gh;
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if (conn->ho) {
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struct lchan_signal_data sig;
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struct gsm48_hdr *gh = msgb_l3(msg);
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LOGPLCHAN(msg->lchan, DRR, LOGL_DEBUG, "ASSIGNMENT FAILED cause = %s\n",
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rr_cause_name(gh->data[0]));
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sig.lchan = msg->lchan;
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sig.mr = NULL;
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osmo_signal_dispatch(SS_LCHAN, S_LCHAN_ASSIGNMENT_FAIL, &sig);
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/* FIXME: release allocated new channel */
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/* send pending messages, if any */
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ho_dtap_cache_flush(conn, 1);
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return;
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}
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if (conn->lchan != msg->lchan) {
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LOGPLCHAN(msg->lchan, DMSC, LOGL_ERROR,
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"Assignment failure should occur on primary lchan.\n");
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return;
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}
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/* stop the timer and release it */
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if (conn->secondary_lchan) {
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lchan_release(conn->secondary_lchan, 0, RSL_REL_LOCAL_END);
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conn->secondary_lchan = NULL;
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}
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/* send pending messages, if any */
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ho_dtap_cache_flush(conn, 1);
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gh = msgb_l3(msg);
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if (msgb_l3len(msg) - sizeof(*gh) != 1) {
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LOGPLCHAN(conn->lchan, DMSC, LOGL_ERROR, "assignment failure unhandled: %zu\n",
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msgb_l3len(msg) - sizeof(*gh));
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rr_failure = NULL;
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} else {
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rr_failure = &gh->data[0];
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}
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bsc_assign_fail(conn, GSM0808_CAUSE_RADIO_INTERFACE_MESSAGE_FAILURE, rr_failure);
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}
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static void handle_classmark_chg(struct gsm_subscriber_connection *conn,
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struct msgb *msg)
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{
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struct gsm48_hdr *gh = msgb_l3(msg);
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unsigned int payload_len = msgb_l3len(msg) - sizeof(*gh);
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uint8_t cm2_len, cm3_len = 0;
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uint8_t *cm2, *cm3 = NULL;
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LOGPLCHAN(msg->lchan, DRR, LOGL_DEBUG, "CLASSMARK CHANGE ");
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/* classmark 2 */
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cm2_len = gh->data[0];
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cm2 = &gh->data[1];
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DEBUGPC(DRR, "CM2(len=%u) ", cm2_len);
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if (payload_len > cm2_len + 1) {
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/* we must have a classmark3 */
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if (gh->data[cm2_len+1] != 0x20) {
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DEBUGPC(DRR, "ERR CM3 TAG\n");
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return;
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}
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if (cm2_len > 3) {
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DEBUGPC(DRR, "CM2 too long!\n");
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return;
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}
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cm3_len = gh->data[cm2_len+2];
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cm3 = &gh->data[cm2_len+3];
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if (cm3_len > 14) {
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DEBUGPC(DRR, "CM3 len %u too long!\n", cm3_len);
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return;
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}
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DEBUGPC(DRR, "CM3(len=%u)\n", cm3_len);
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}
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bsc_cm_update(conn, cm2, cm2_len, cm3, cm3_len);
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}
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/* Chapter 9.1.16 Handover complete */
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static void handle_rr_ho_compl(struct msgb *msg)
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{
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struct lchan_signal_data sig;
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struct gsm48_hdr *gh = msgb_l3(msg);
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LOGPLCHAN(msg->lchan, DRR, LOGL_DEBUG,
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"HANDOVER COMPLETE cause = %s\n", rr_cause_name(gh->data[0]));
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sig.lchan = msg->lchan;
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sig.mr = NULL;
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osmo_signal_dispatch(SS_LCHAN, S_LCHAN_HANDOVER_COMPL, &sig);
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/* FIXME: release old channel */
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/* send pending messages, if any */
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ho_dtap_cache_flush(msg->lchan->conn, 1);
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}
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|
|
/* Chapter 9.1.17 Handover Failure */
|
|
static void handle_rr_ho_fail(struct msgb *msg)
|
|
{
|
|
struct lchan_signal_data sig;
|
|
struct gsm48_hdr *gh = msgb_l3(msg);
|
|
|
|
/* Log on both RR and HO categories: it is an RR message, but is still quite important when
|
|
* filtering on HO. */
|
|
LOGPLCHAN(msg->lchan, DRR, LOGL_DEBUG,
|
|
"HANDOVER FAILED cause = %s\n", rr_cause_name(gh->data[0]));
|
|
LOGPLCHAN(msg->lchan, DHO, LOGL_DEBUG,
|
|
"HANDOVER FAILED cause = %s\n", rr_cause_name(gh->data[0]));
|
|
|
|
sig.lchan = msg->lchan;
|
|
sig.mr = NULL;
|
|
osmo_signal_dispatch(SS_LCHAN, S_LCHAN_HANDOVER_FAIL, &sig);
|
|
/* FIXME: release allocated new channel */
|
|
|
|
/* send pending messages, if any */
|
|
ho_dtap_cache_flush(msg->lchan->conn, 1);
|
|
}
|
|
|
|
|
|
static void dispatch_dtap(struct gsm_subscriber_connection *conn,
|
|
uint8_t link_id, struct msgb *msg)
|
|
{
|
|
struct gsm48_hdr *gh;
|
|
uint8_t pdisc;
|
|
uint8_t msg_type;
|
|
int rc;
|
|
|
|
if (msgb_l3len(msg) < sizeof(*gh)) {
|
|
LOGP(DMSC, LOGL_ERROR, "(%s) Message too short for a GSM48 header.\n",
|
|
bsc_subscr_name(conn->bsub));
|
|
return;
|
|
}
|
|
|
|
gh = msgb_l3(msg);
|
|
pdisc = gsm48_hdr_pdisc(gh);
|
|
msg_type = gsm48_hdr_msg_type(gh);
|
|
|
|
/* the idea is to handle all RR messages here, and only hand
|
|
* MM/CC/SMS-CP/LCS up to the MSC. Some messages like PAGING
|
|
* RESPONSE or CM SERVICE REQUEST will not be covered here, as
|
|
* they are only possible in the first L3 message of each L2
|
|
* channel, i.e. 'conn' will not exist and gsm0408_rcvmsg()
|
|
* will call api->compl_l3() for it */
|
|
switch (pdisc) {
|
|
case GSM48_PDISC_RR:
|
|
switch (msg_type) {
|
|
case GSM48_MT_RR_GPRS_SUSP_REQ:
|
|
LOGPLCHAN(msg->lchan, DRR, LOGL_DEBUG,
|
|
"%s\n", gsm48_rr_msg_name(GSM48_MT_RR_GPRS_SUSP_REQ));
|
|
break;
|
|
case GSM48_MT_RR_STATUS:
|
|
LOGPLCHAN(msg->lchan, DRR, LOGL_NOTICE,
|
|
"%s (cause: %s)\n", gsm48_rr_msg_name(GSM48_MT_RR_STATUS),
|
|
rr_cause_name(gh->data[0]));
|
|
break;
|
|
case GSM48_MT_RR_MEAS_REP:
|
|
/* This shouldn't actually end up here, as RSL treats
|
|
* L3 Info of 08.58 MEASUREMENT REPORT different by calling
|
|
* directly into gsm48_parse_meas_rep */
|
|
LOGPLCHAN(msg->lchan, DMEAS, LOGL_ERROR,
|
|
"DIRECT GSM48 MEASUREMENT REPORT ?!?\n");
|
|
gsm48_tx_rr_status(conn, GSM48_RR_CAUSE_MSG_TYPE_N_COMPAT);
|
|
break;
|
|
case GSM48_MT_RR_HANDO_COMPL:
|
|
handle_rr_ho_compl(msg);
|
|
break;
|
|
case GSM48_MT_RR_HANDO_FAIL:
|
|
handle_rr_ho_fail(msg);
|
|
break;
|
|
case GSM48_MT_RR_CIPH_M_COMPL:
|
|
bsc_cipher_mode_compl(conn, msg, conn->lchan->encr.alg_id);
|
|
break;
|
|
case GSM48_MT_RR_ASS_COMPL:
|
|
handle_ass_compl(conn, msg);
|
|
break;
|
|
case GSM48_MT_RR_ASS_FAIL:
|
|
handle_ass_fail(conn, msg);
|
|
break;
|
|
case GSM48_MT_RR_CHAN_MODE_MODIF_ACK:
|
|
rc = gsm48_rx_rr_modif_ack(msg);
|
|
if (rc < 0)
|
|
bsc_assign_fail(conn, GSM0808_CAUSE_NO_RADIO_RESOURCE_AVAILABLE, NULL);
|
|
else
|
|
bsc_assign_compl(conn, 0);
|
|
break;
|
|
case GSM48_MT_RR_CLSM_CHG:
|
|
handle_classmark_chg(conn, msg);
|
|
break;
|
|
case GSM48_MT_RR_APP_INFO:
|
|
/* Passing RR APP INFO to MSC, not quite
|
|
* according to spec */
|
|
bsc_dtap(conn, link_id, msg);
|
|
break;
|
|
default:
|
|
/* Drop unknown RR message */
|
|
LOGPLCHAN(msg->lchan, DRR, LOGL_NOTICE,
|
|
"Dropping %s 04.08 RR message\n", gsm48_rr_msg_name(msg_type));
|
|
gsm48_tx_rr_status(conn, GSM48_RR_CAUSE_MSG_TYPE_N);
|
|
break;
|
|
}
|
|
break;
|
|
default:
|
|
bsc_dtap(conn, link_id, msg);
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*! \brief RSL has received a DATA INDICATION with L3 from MS */
|
|
int gsm0408_rcvmsg(struct msgb *msg, uint8_t link_id)
|
|
{
|
|
int rc;
|
|
struct gsm_lchan *lchan;
|
|
|
|
lchan = msg->lchan;
|
|
if (lchan->state != LCHAN_S_ACTIVE) {
|
|
LOGPLCHAN(msg->lchan, DRSL, LOGL_INFO, "Got data in non active state, discarding.\n");
|
|
return -1;
|
|
}
|
|
|
|
|
|
if (lchan->conn) {
|
|
/* if we already have a connection, forward via DTAP to
|
|
* MSC */
|
|
dispatch_dtap(lchan->conn, link_id, msg);
|
|
} else {
|
|
/* allocate a new connection */
|
|
rc = BSC_API_CONN_POL_REJECT;
|
|
lchan->conn = bsc_subscr_con_allocate(msg->lchan->ts->trx->bts->network);
|
|
if (!lchan->conn) {
|
|
lchan_release(lchan, 1, RSL_REL_NORMAL);
|
|
return -1;
|
|
}
|
|
lchan->conn->lchan = lchan;
|
|
|
|
/* fwd via bsc_api to send COMPLETE L3 INFO to MSC */
|
|
rc = bsc_compl_l3(lchan->conn, msg, 0);
|
|
|
|
if (rc != BSC_API_CONN_POL_ACCEPT) {
|
|
//osmo_fsm_inst_dispatch(lchan->conn->fi, FIXME, NULL);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*! \brief We received a GSM 08.08 CIPHER MODE from the MSC */
|
|
int gsm0808_cipher_mode(struct gsm_subscriber_connection *conn, int cipher,
|
|
const uint8_t *key, int len, int include_imeisv)
|
|
{
|
|
if (cipher > 0 && key == NULL) {
|
|
LOGP(DRSL, LOGL_ERROR, "%s: Need to have an encryption key.\n",
|
|
bsc_subscr_name(conn->bsub));
|
|
return -1;
|
|
}
|
|
|
|
if (len > MAX_A5_KEY_LEN) {
|
|
LOGP(DRSL, LOGL_ERROR, "%s: The key is too long: %d\n",
|
|
bsc_subscr_name(conn->bsub), len);
|
|
return -1;
|
|
}
|
|
|
|
LOGP(DRSL, LOGL_DEBUG, "(subscr %s) Cipher Mode: cipher=%d key=%s include_imeisv=%d\n",
|
|
bsc_subscr_name(conn->bsub), cipher, osmo_hexdump_nospc(key, len), include_imeisv);
|
|
|
|
conn->lchan->encr.alg_id = RSL_ENC_ALG_A5(cipher);
|
|
if (key) {
|
|
conn->lchan->encr.key_len = len;
|
|
memcpy(conn->lchan->encr.key, key, len);
|
|
}
|
|
|
|
return gsm48_send_rr_ciph_mode(conn->lchan, include_imeisv);
|
|
}
|
|
|
|
/*
|
|
* Release all occupied RF Channels but stay around for more.
|
|
*/
|
|
int gsm0808_clear(struct gsm_subscriber_connection *conn)
|
|
{
|
|
if (conn->ho)
|
|
bsc_clear_handover(conn, 1);
|
|
|
|
if (conn->secondary_lchan)
|
|
lchan_release(conn->secondary_lchan, 0, RSL_REL_LOCAL_END);
|
|
|
|
if (conn->lchan)
|
|
lchan_release(conn->lchan, 1, RSL_REL_NORMAL);
|
|
|
|
conn->lchan = NULL;
|
|
conn->secondary_lchan = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void rll_ind_cb(struct gsm_lchan *lchan, uint8_t link_id, void *_data, enum bsc_rllr_ind rllr_ind)
|
|
{
|
|
struct msgb *msg = _data;
|
|
|
|
/*
|
|
* There seems to be a small window that the RLL timer can
|
|
* fire after a lchan_release call and before the S_CHALLOC_FREED
|
|
* is called. Check if a conn is set before proceeding.
|
|
*/
|
|
if (!lchan->conn)
|
|
return;
|
|
|
|
switch (rllr_ind) {
|
|
case BSC_RLLR_IND_EST_CONF:
|
|
rsl_data_request(msg, OBSC_LINKID_CB(msg));
|
|
break;
|
|
case BSC_RLLR_IND_REL_IND:
|
|
case BSC_RLLR_IND_ERR_IND:
|
|
case BSC_RLLR_IND_TIMEOUT:
|
|
bsc_sapi_n_reject(lchan->conn, OBSC_LINKID_CB(msg));
|
|
msgb_free(msg);
|
|
break;
|
|
}
|
|
}
|
|
|
|
static int bsc_handle_lchan_signal(unsigned int subsys, unsigned int signal,
|
|
void *handler_data, void *signal_data)
|
|
{
|
|
struct gsm_lchan *lchan;
|
|
struct lchan_signal_data *lchan_data;
|
|
|
|
if (subsys != SS_LCHAN)
|
|
return 0;
|
|
|
|
|
|
lchan_data = signal_data;
|
|
if (!lchan_data->lchan || !lchan_data->lchan->conn)
|
|
return 0;
|
|
|
|
lchan = lchan_data->lchan;
|
|
|
|
switch (signal) {
|
|
case S_LCHAN_UNEXPECTED_RELEASE:
|
|
LOGPLCHAN(lchan, DMSC, LOGL_NOTICE, "S_LCHAN_UNEXPECTED_RELEASE\n");
|
|
handle_release(lchan->conn, lchan);
|
|
break;
|
|
case S_LCHAN_ACTIVATE_ACK:
|
|
handle_chan_ack(lchan->conn, lchan);
|
|
break;
|
|
case S_LCHAN_ACTIVATE_NACK:
|
|
handle_chan_nack(lchan->conn, lchan);
|
|
break;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void handle_release(struct gsm_subscriber_connection *conn, struct gsm_lchan *lchan)
|
|
{
|
|
if (conn->secondary_lchan == lchan) {
|
|
LOGPLCHAN(lchan, DMSC, LOGL_NOTICE,
|
|
"lchan release on new lchan, Assignment failed\n");
|
|
conn->secondary_lchan = NULL;
|
|
|
|
bsc_assign_fail(conn, GSM0808_CAUSE_RADIO_INTERFACE_FAILURE, NULL);
|
|
}
|
|
|
|
/* clear the connection now */
|
|
bsc_clear_request(conn, 0);
|
|
|
|
/* now give up all channels */
|
|
if (conn->lchan == lchan)
|
|
conn->lchan = NULL;
|
|
if (conn->ho && conn->ho->new_lchan == lchan)
|
|
bsc_clear_handover(conn, 0);
|
|
lchan->conn = NULL;
|
|
}
|
|
|
|
static void handle_chan_ack(struct gsm_subscriber_connection *conn, struct gsm_lchan *lchan)
|
|
{
|
|
if (conn->secondary_lchan != lchan)
|
|
return;
|
|
|
|
LOGPLCHAN(lchan, DMSC, LOGL_NOTICE, "Sending RR Assignment\n");
|
|
gsm48_send_rr_ass_cmd(conn->lchan, lchan, lchan->ms_power);
|
|
}
|
|
|
|
static void handle_chan_nack(struct gsm_subscriber_connection *conn, struct gsm_lchan *lchan)
|
|
{
|
|
if (conn->secondary_lchan != lchan)
|
|
return;
|
|
|
|
LOGPLCHAN(lchan, DMSC, LOGL_ERROR, "Channel activation failed.\n");
|
|
conn->secondary_lchan->conn = NULL;
|
|
conn->secondary_lchan = NULL;
|
|
bsc_assign_fail(conn, GSM0808_CAUSE_RADIO_INTERFACE_FAILURE, NULL);
|
|
}
|
|
|
|
static __attribute__((constructor)) void on_dso_load_bsc(void)
|
|
{
|
|
osmo_signal_register_handler(SS_LCHAN, bsc_handle_lchan_signal, NULL);
|
|
}
|