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-rw-r--r--src/libbsc/rest_octets.c432
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diff --git a/src/libbsc/rest_octets.c b/src/libbsc/rest_octets.c
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+/* GSM Mobile Radio Interface Layer 3 messages on the A-bis interface,
+ * rest octet handling according to
+ * 3GPP TS 04.08 version 7.21.0 Release 1998 / ETSI TS 100 940 V7.21.0 */
+
+/* (C) 2009 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 <string.h>
+#include <stdlib.h>
+#include <errno.h>
+
+#include <openbsc/gsm_data.h>
+#include <osmocore/bitvec.h>
+#include <openbsc/rest_octets.h>
+
+/* generate SI1 rest octets */
+int rest_octets_si1(u_int8_t *data, u_int8_t *nch_pos)
+{
+ struct bitvec bv;
+
+ memset(&bv, 0, sizeof(bv));
+ bv.data = data;
+ bv.data_len = 1;
+
+ if (nch_pos) {
+ bitvec_set_bit(&bv, H);
+ bitvec_set_uint(&bv, *nch_pos, 5);
+ } else
+ bitvec_set_bit(&bv, L);
+
+ bitvec_spare_padding(&bv, 7);
+ return bv.data_len;
+}
+
+/* Append selection parameters to bitvec */
+static void append_selection_params(struct bitvec *bv,
+ const struct gsm48_si_selection_params *sp)
+{
+ if (sp->present) {
+ bitvec_set_bit(bv, H);
+ bitvec_set_bit(bv, sp->cbq);
+ bitvec_set_uint(bv, sp->cell_resel_off, 6);
+ bitvec_set_uint(bv, sp->temp_offs, 3);
+ bitvec_set_uint(bv, sp->penalty_time, 5);
+ } else
+ bitvec_set_bit(bv, L);
+}
+
+/* Append power offset to bitvec */
+static void append_power_offset(struct bitvec *bv,
+ const struct gsm48_si_power_offset *po)
+{
+ if (po->present) {
+ bitvec_set_bit(bv, H);
+ bitvec_set_uint(bv, po->power_offset, 2);
+ } else
+ bitvec_set_bit(bv, L);
+}
+
+/* Append GPRS indicator to bitvec */
+static void append_gprs_ind(struct bitvec *bv,
+ const struct gsm48_si3_gprs_ind *gi)
+{
+ if (gi->present) {
+ bitvec_set_bit(bv, H);
+ bitvec_set_uint(bv, gi->ra_colour, 3);
+ /* 0 == SI13 in BCCH Norm, 1 == SI13 sent on BCCH Ext */
+ bitvec_set_bit(bv, gi->si13_position);
+ } else
+ bitvec_set_bit(bv, L);
+}
+
+
+/* Generate SI3 Rest Octests (Chapter 10.5.2.34 / Table 10.4.72) */
+int rest_octets_si3(u_int8_t *data, const struct gsm48_si_ro_info *si3)
+{
+ struct bitvec bv;
+
+ memset(&bv, 0, sizeof(bv));
+ bv.data = data;
+ bv.data_len = 4;
+
+ /* Optional Selection Parameters */
+ append_selection_params(&bv, &si3->selection_params);
+
+ /* Optional Power Offset */
+ append_power_offset(&bv, &si3->power_offset);
+
+ /* Do we have a SI2ter on the BCCH? */
+ if (si3->si2ter_indicator)
+ bitvec_set_bit(&bv, H);
+ else
+ bitvec_set_bit(&bv, L);
+
+ /* Early Classmark Sending Control */
+ if (si3->early_cm_ctrl)
+ bitvec_set_bit(&bv, H);
+ else
+ bitvec_set_bit(&bv, L);
+
+ /* Do we have a SI Type 9 on the BCCH? */
+ if (si3->scheduling.present) {
+ bitvec_set_bit(&bv, H);
+ bitvec_set_uint(&bv, si3->scheduling.where, 3);
+ } else
+ bitvec_set_bit(&bv, L);
+
+ /* GPRS Indicator */
+ append_gprs_ind(&bv, &si3->gprs_ind);
+
+ bitvec_spare_padding(&bv, (bv.data_len*8)-1);
+ return bv.data_len;
+}
+
+static int append_lsa_params(struct bitvec *bv,
+ const struct gsm48_lsa_params *lsa_params)
+{
+ /* FIXME */
+ return -1;
+}
+
+/* Generate SI4 Rest Octets (Chapter 10.5.2.35) */
+int rest_octets_si4(u_int8_t *data, const struct gsm48_si_ro_info *si4)
+{
+ struct bitvec bv;
+
+ memset(&bv, 0, sizeof(bv));
+ bv.data = data;
+ bv.data_len = 10; /* FIXME: up to ? */
+
+ /* SI4 Rest Octets O */
+ append_selection_params(&bv, &si4->selection_params);
+ append_power_offset(&bv, &si4->power_offset);
+ append_gprs_ind(&bv, &si4->gprs_ind);
+
+ if (0 /* FIXME */) {
+ /* H and SI4 Rest Octets S */
+ bitvec_set_bit(&bv, H);
+
+ /* LSA Parameters */
+ if (si4->lsa_params.present) {
+ bitvec_set_bit(&bv, H);
+ append_lsa_params(&bv, &si4->lsa_params);
+ } else
+ bitvec_set_bit(&bv, L);
+
+ /* Cell Identity */
+ if (1) {
+ bitvec_set_bit(&bv, H);
+ bitvec_set_uint(&bv, si4->cell_id, 16);
+ } else
+ bitvec_set_bit(&bv, L);
+
+ /* LSA ID Information */
+ if (0) {
+ bitvec_set_bit(&bv, H);
+ /* FIXME */
+ } else
+ bitvec_set_bit(&bv, L);
+ } else {
+ /* L and break indicator */
+ bitvec_set_bit(&bv, L);
+ bitvec_set_bit(&bv, si4->break_ind ? H : L);
+ }
+
+ return bv.data_len;
+}
+
+/* GPRS Mobile Allocation as per TS 04.60 Chapter 12.10a:
+ < GPRS Mobile Allocation IE > ::=
+ < HSN : bit (6) >
+ { 0 | 1 < RFL number list : < RFL number list struct > > }
+ { 0 < MA_LENGTH : bit (6) >
+ < MA_BITMAP: bit (val(MA_LENGTH) + 1) >
+ | 1 { 0 | 1 <ARFCN index list : < ARFCN index list struct > > } } ;
+
+ < RFL number list struct > :: =
+ < RFL_NUMBER : bit (4) >
+ { 0 | 1 < RFL number list struct > } ;
+ < ARFCN index list struct > ::=
+ < ARFCN_INDEX : bit(6) >
+ { 0 | 1 < ARFCN index list struct > } ;
+ */
+static int append_gprs_mobile_alloc(struct bitvec *bv)
+{
+ /* Hopping Sequence Number */
+ bitvec_set_uint(bv, 0, 6);
+
+ if (0) {
+ /* We want to use a RFL number list */
+ bitvec_set_bit(bv, 1);
+ /* FIXME: RFL number list */
+ } else
+ bitvec_set_bit(bv, 0);
+
+ if (0) {
+ /* We want to use a MA_BITMAP */
+ bitvec_set_bit(bv, 0);
+ /* FIXME: MA_LENGTH, MA_BITMAP, ... */
+ } else {
+ bitvec_set_bit(bv, 1);
+ if (0) {
+ /* We want to provide an ARFCN index list */
+ bitvec_set_bit(bv, 1);
+ /* FIXME */
+ } else
+ bitvec_set_bit(bv, 0);
+ }
+ return 0;
+}
+
+static int encode_t3192(unsigned int t3192)
+{
+ if (t3192 == 0)
+ return 3;
+ else if (t3192 <= 80)
+ return 4;
+ else if (t3192 <= 120)
+ return 5;
+ else if (t3192 <= 160)
+ return 6;
+ else if (t3192 <= 200)
+ return 7;
+ else if (t3192 <= 500)
+ return 0;
+ else if (t3192 <= 1000)
+ return 1;
+ else if (t3192 <= 1500)
+ return 2;
+ else
+ return -EINVAL;
+}
+
+static int encode_drx_timer(unsigned int drx)
+{
+ if (drx == 0)
+ return 0;
+ else if (drx == 1)
+ return 1;
+ else if (drx == 2)
+ return 2;
+ else if (drx <= 4)
+ return 3;
+ else if (drx <= 8)
+ return 4;
+ else if (drx <= 16)
+ return 5;
+ else if (drx <= 32)
+ return 6;
+ else if (drx <= 64)
+ return 7;
+ else
+ return -EINVAL;
+}
+
+/* GPRS Cell Options as per TS 04.60 Chapter 12.24
+ < GPRS Cell Options IE > ::=
+ < NMO : bit(2) >
+ < T3168 : bit(3) >
+ < T3192 : bit(3) >
+ < DRX_TIMER_MAX: bit(3) >
+ < ACCESS_BURST_TYPE: bit >
+ < CONTROL_ACK_TYPE : bit >
+ < BS_CV_MAX: bit(4) >
+ { 0 | 1 < PAN_DEC : bit(3) >
+ < PAN_INC : bit(3) >
+ < PAN_MAX : bit(3) >
+ { 0 | 1 < Extension Length : bit(6) >
+ < bit (val(Extension Length) + 1
+ & { < Extension Information > ! { bit ** = <no string> } } ;
+ < Extension Information > ::=
+ { 0 | 1 < EGPRS_PACKET_CHANNEL_REQUEST : bit >
+ < BEP_PERIOD : bit(4) > }
+ < PFC_FEATURE_MODE : bit >
+ < DTM_SUPPORT : bit >
+ <BSS_PAGING_COORDINATION: bit >
+ <spare bit > ** ;
+ */
+static int append_gprs_cell_opt(struct bitvec *bv,
+ const struct gprs_cell_options *gco)
+{
+ int t3192, drx_timer_max;
+
+ t3192 = encode_t3192(gco->t3192);
+ if (t3192 < 0)
+ return t3192;
+
+ drx_timer_max = encode_drx_timer(gco->drx_timer_max);
+ if (drx_timer_max < 0)
+ return drx_timer_max;
+
+ bitvec_set_uint(bv, gco->nmo, 2);
+ bitvec_set_uint(bv, gco->t3168 / 500, 3);
+ bitvec_set_uint(bv, t3192, 3);
+ bitvec_set_uint(bv, drx_timer_max, 3);
+ /* ACCESS_BURST_TYPE: Hard-code 8bit */
+ bitvec_set_bit(bv, 0);
+ /* CONTROL_ACK_TYPE: Hard-code to RLC/MAC control block */
+ bitvec_set_bit(bv, 1);
+ bitvec_set_uint(bv, gco->bs_cv_max, 4);
+
+ if (0) {
+ /* hard-code no PAN_{DEC,INC,MAX} */
+ bitvec_set_bit(bv, 0);
+ } else {
+ /* copied from ip.access BSC protocol trace */
+ bitvec_set_bit(bv, 1);
+ bitvec_set_uint(bv, 1, 3); /* DEC */
+ bitvec_set_uint(bv, 1, 3); /* INC */
+ bitvec_set_uint(bv, 15, 3); /* MAX */
+ }
+
+ if (!gco->ext_info_present) {
+ /* no extension information */
+ bitvec_set_bit(bv, 0);
+ } else {
+ /* extension information */
+ bitvec_set_bit(bv, 1);
+ if (!gco->ext_info.egprs_supported) {
+ /* 6bit length of extension */
+ bitvec_set_uint(bv, (1 + 3)-1, 6);
+ /* EGPRS supported in the cell */
+ bitvec_set_bit(bv, 0);
+ } else {
+ /* 6bit length of extension */
+ bitvec_set_uint(bv, (1 + 5 + 3)-1, 6);
+ /* EGPRS supported in the cell */
+ bitvec_set_bit(bv, 1);
+ /* 1bit EGPRS PACKET CHANNEL REQUEST */
+ bitvec_set_bit(bv, gco->ext_info.use_egprs_p_ch_req);
+ /* 4bit BEP PERIOD */
+ bitvec_set_uint(bv, gco->ext_info.bep_period, 4);
+ }
+ bitvec_set_bit(bv, gco->ext_info.pfc_supported);
+ bitvec_set_bit(bv, gco->ext_info.dtm_supported);
+ bitvec_set_bit(bv, gco->ext_info.bss_paging_coordination);
+ }
+
+ return 0;
+}
+
+static void append_gprs_pwr_ctrl_pars(struct bitvec *bv,
+ const struct gprs_power_ctrl_pars *pcp)
+{
+ bitvec_set_uint(bv, pcp->alpha, 4);
+ bitvec_set_uint(bv, pcp->t_avg_w, 5);
+ bitvec_set_uint(bv, pcp->t_avg_t, 5);
+ bitvec_set_uint(bv, pcp->pc_meas_chan, 1);
+ bitvec_set_uint(bv, pcp->n_avg_i, 4);
+}
+
+/* Generate SI13 Rest Octests (04.08 Chapter 10.5.2.37b) */
+int rest_octets_si13(u_int8_t *data, const struct gsm48_si13_info *si13)
+{
+ struct bitvec bv;
+
+ memset(&bv, 0, sizeof(bv));
+ bv.data = data;
+ bv.data_len = 20;
+
+ if (0) {
+ /* No rest octets */
+ bitvec_set_bit(&bv, L);
+ } else {
+ bitvec_set_bit(&bv, H);
+ bitvec_set_uint(&bv, si13->bcch_change_mark, 3);
+ bitvec_set_uint(&bv, si13->si_change_field, 4);
+ if (1) {
+ bitvec_set_bit(&bv, 0);
+ } else {
+ bitvec_set_bit(&bv, 1);
+ bitvec_set_uint(&bv, si13->bcch_change_mark, 2);
+ append_gprs_mobile_alloc(&bv);
+ }
+ if (!si13->pbcch_present) {
+ /* PBCCH not present in cell */
+ bitvec_set_bit(&bv, 0);
+ bitvec_set_uint(&bv, si13->no_pbcch.rac, 8);
+ bitvec_set_bit(&bv, si13->no_pbcch.spgc_ccch_sup);
+ bitvec_set_uint(&bv, si13->no_pbcch.prio_acc_thr, 3);
+ bitvec_set_uint(&bv, si13->no_pbcch.net_ctrl_ord, 2);
+ append_gprs_cell_opt(&bv, &si13->cell_opts);
+ append_gprs_pwr_ctrl_pars(&bv, &si13->pwr_ctrl_pars);
+ } else {
+ /* PBCCH present in cell */
+ bitvec_set_bit(&bv, 1);
+ bitvec_set_uint(&bv, si13->pbcch.psi1_rep_per, 4);
+ /* PBCCH Descripiton */
+ bitvec_set_uint(&bv, si13->pbcch.pb, 4);
+ bitvec_set_uint(&bv, si13->pbcch.tsc, 3);
+ bitvec_set_uint(&bv, si13->pbcch.tn, 3);
+ switch (si13->pbcch.carrier_type) {
+ case PBCCH_BCCH:
+ bitvec_set_bit(&bv, 0);
+ bitvec_set_bit(&bv, 0);
+ break;
+ case PBCCH_ARFCN:
+ bitvec_set_bit(&bv, 0);
+ bitvec_set_bit(&bv, 1);
+ bitvec_set_uint(&bv, si13->pbcch.arfcn, 10);
+ break;
+ case PBCCH_MAIO:
+ bitvec_set_bit(&bv, 1);
+ bitvec_set_uint(&bv, si13->pbcch.maio, 6);
+ break;
+ }
+ }
+ /* 3GPP TS 44.018 Release 6 / 10.5.2.37b */
+ bitvec_set_bit(&bv, H); /* added Release 99 */
+ /* claim our SGSN is compatible with Release 99, as EDGE and EGPRS
+ * was only added in this Release */
+ bitvec_set_bit(&bv, 1);
+ }
+ bitvec_spare_padding(&bv, (bv.data_len*8)-1);
+ return bv.data_len;
+}