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Diffstat (limited to 'openbsc/src/rest_octets.c')
| -rw-r--r-- | openbsc/src/rest_octets.c | 394 |
1 files changed, 394 insertions, 0 deletions
diff --git a/openbsc/src/rest_octets.c b/openbsc/src/rest_octets.c new file mode 100644 index 000000000..6226203ec --- /dev/null +++ b/openbsc/src/rest_octets.c @@ -0,0 +1,394 @@ +/* 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 General Public License as published by + * the Free Software Foundation; either version 2 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + * + */ + +#include <string.h> +#include <stdlib.h> +#include <errno.h> + +#include <openbsc/gsm_data.h> +#include <openbsc/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 = 2; + + 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, 15); + return 0; +} + +/* 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 = 5; + + /* 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); + + return bitvec_spare_padding(&bv, (bv.data_len*8)-1); +} + +static int append_lsa_params(struct bitvec *bv, + const struct gsm48_lsa_params *lsa_params) +{ + /* FIXME */ +} + +/* 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 = 11; /* 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 0; +} + +/* 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); + + /* hard-code no PAN_{DEC,INC,MAX} */ + bitvec_set_bit(bv, 0); + + /* no extension information (EDGE) */ + bitvec_set_bit(bv, 0); + + 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 (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 = 21; + + 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 (0) { + 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; + } + } + } + return bitvec_spare_padding(&bv, (bv.data_len*8)-1); +} |