| /* GSM 04.08 System Information (SI) encoding and decoding |
| * 3GPP TS 04.08 version 7.21.0 Release 1998 / ETSI TS 100 940 V7.21.0 */ |
| |
| /* (C) 2008-2010 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 <errno.h> |
| #include <string.h> |
| #include <stdio.h> |
| #include <netinet/in.h> |
| |
| #include <osmocom/core/bitvec.h> |
| #include <osmocom/core/utils.h> |
| #include <osmocom/gsm/sysinfo.h> |
| |
| #include <openbsc/debug.h> |
| #include <openbsc/gsm_04_08.h> |
| #include <openbsc/gsm_data.h> |
| #include <openbsc/abis_rsl.h> |
| #include <openbsc/rest_octets.h> |
| |
| |
| /* Frequency Lists as per TS 04.08 10.5.2.13 */ |
| |
| /* 10.5.2.13.2: Bit map 0 format */ |
| static int freq_list_bm0_set_arfcn(uint8_t *chan_list, unsigned int arfcn) |
| { |
| unsigned int byte, bit; |
| |
| if (arfcn > 124 || arfcn < 1) { |
| LOGP(DRR, LOGL_ERROR, "Bitmap 0 only supports ARFCN 1...124\n"); |
| return -EINVAL; |
| } |
| |
| /* the bitmask is from 1..124, not from 0..123 */ |
| arfcn--; |
| |
| byte = arfcn / 8; |
| bit = arfcn % 8; |
| |
| chan_list[GSM48_CELL_CHAN_DESC_SIZE-1-byte] |= (1 << bit); |
| |
| return 0; |
| } |
| |
| /* 10.5.2.13.7: Variable bit map format */ |
| static int freq_list_bmrel_set_arfcn(uint8_t *chan_list, unsigned int arfcn) |
| { |
| unsigned int byte, bit; |
| unsigned int min_arfcn; |
| unsigned int bitno; |
| |
| min_arfcn = (chan_list[0] & 1) << 9; |
| min_arfcn |= chan_list[1] << 1; |
| min_arfcn |= (chan_list[2] >> 7) & 1; |
| |
| /* The lower end of our bitmaks is always implicitly included */ |
| if (arfcn == min_arfcn) |
| return 0; |
| |
| if (arfcn < min_arfcn) { |
| LOGP(DRR, LOGL_ERROR, "arfcn(%u) < min(%u)\n", arfcn, min_arfcn); |
| return -EINVAL; |
| } |
| if (arfcn > min_arfcn + 111) { |
| LOGP(DRR, LOGL_ERROR, "arfcn(%u) > min(%u) + 111\n", arfcn, min_arfcn); |
| return -EINVAL; |
| } |
| |
| bitno = (arfcn - min_arfcn); |
| byte = bitno / 8; |
| bit = bitno % 8; |
| |
| chan_list[2 + byte] |= 1 << (7 - bit); |
| |
| return 0; |
| } |
| |
| /* generate a cell channel list as per Section 10.5.2.1b of 04.08 */ |
| static int bitvec2freq_list(uint8_t *chan_list, struct bitvec *bv, |
| const struct gsm_bts *bts) |
| { |
| int i, rc, min = 1024, max = -1; |
| |
| memset(chan_list, 0, 16); |
| |
| /* GSM900-only handsets only support 'bit map 0 format' */ |
| if (bts->band == GSM_BAND_900) { |
| chan_list[0] = 0; |
| |
| for (i = 0; i < bv->data_len*8; i++) { |
| if (bitvec_get_bit_pos(bv, i)) { |
| rc = freq_list_bm0_set_arfcn(chan_list, i); |
| if (rc < 0) |
| return rc; |
| } |
| } |
| return 0; |
| } |
| |
| /* We currently only support the 'Variable bitmap format' */ |
| chan_list[0] = 0x8e; |
| |
| for (i = 0; i < bv->data_len*8; i++) { |
| if (bitvec_get_bit_pos(bv, i)) { |
| if (i < min) |
| min = i; |
| if (i > max) |
| max = i; |
| } |
| } |
| |
| if (max == -1) { |
| /* Empty set, use 'bit map 0 format' */ |
| chan_list[0] = 0; |
| return 0; |
| } |
| |
| if ((max - min) > 111) { |
| LOGP(DRR, LOGL_ERROR, "min_arfcn=%u, max_arfcn=%u, " |
| "distance > 111\n", min, max); |
| return -EINVAL; |
| } |
| |
| chan_list[0] |= (min >> 9) & 1; |
| chan_list[1] = (min >> 1); |
| chan_list[2] = (min & 1) << 7; |
| |
| for (i = 0; i < bv->data_len*8; i++) { |
| if (bitvec_get_bit_pos(bv, i)) { |
| rc = freq_list_bmrel_set_arfcn(chan_list, i); |
| if (rc < 0) |
| return rc; |
| } |
| } |
| |
| return 0; |
| } |
| |
| /* generate a cell channel list as per Section 10.5.2.1b of 04.08 */ |
| static int generate_cell_chan_list(uint8_t *chan_list, struct gsm_bts *bts) |
| { |
| struct gsm_bts_trx *trx; |
| struct bitvec *bv = &bts->si_common.cell_alloc; |
| |
| /* Zero-initialize the bit-vector */ |
| memset(bv->data, 0, bv->data_len); |
| |
| /* first we generate a bitvec of all TRX ARFCN's in our BTS */ |
| llist_for_each_entry(trx, &bts->trx_list, list) { |
| unsigned int i, j; |
| /* Always add the TRX's ARFCN */ |
| bitvec_set_bit_pos(bv, trx->arfcn, 1); |
| for (i = 0; i < ARRAY_SIZE(trx->ts); i++) { |
| struct gsm_bts_trx_ts *ts = &trx->ts[i]; |
| /* Add any ARFCNs present in hopping channels */ |
| for (j = 0; j < 1024; j++) { |
| if (bitvec_get_bit_pos(&ts->hopping.arfcns, j)) |
| bitvec_set_bit_pos(bv, j, 1); |
| } |
| } |
| } |
| |
| /* then we generate a GSM 04.08 frequency list from the bitvec */ |
| return bitvec2freq_list(chan_list, bv, bts); |
| } |
| |
| /* generate a cell channel list as per Section 10.5.2.1b of 04.08 */ |
| static int generate_bcch_chan_list(uint8_t *chan_list, struct gsm_bts *bts, int si5) |
| { |
| struct gsm_bts *cur_bts; |
| struct bitvec *bv; |
| |
| if (si5 && bts->neigh_list_manual_mode == NL_MODE_MANUAL_SI5SEP) |
| bv = &bts->si_common.si5_neigh_list; |
| else |
| bv = &bts->si_common.neigh_list; |
| |
| /* Generate list of neighbor cells if we are in automatic mode */ |
| if (bts->neigh_list_manual_mode == NL_MODE_AUTOMATIC) { |
| /* Zero-initialize the bit-vector */ |
| memset(bv->data, 0, bv->data_len); |
| |
| /* first we generate a bitvec of the BCCH ARFCN's in our BSC */ |
| llist_for_each_entry(cur_bts, &bts->network->bts_list, list) { |
| if (cur_bts == bts) |
| continue; |
| bitvec_set_bit_pos(bv, cur_bts->c0->arfcn, 1); |
| } |
| } |
| |
| /* then we generate a GSM 04.08 frequency list from the bitvec */ |
| return bitvec2freq_list(chan_list, bv, bts); |
| } |
| |
| static int generate_si1(uint8_t *output, struct gsm_bts *bts) |
| { |
| int rc; |
| struct gsm48_system_information_type_1 *si1 = |
| (struct gsm48_system_information_type_1 *) output; |
| |
| memset(si1, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN); |
| |
| si1->header.l2_plen = (21 << 2) | 1; |
| si1->header.rr_protocol_discriminator = GSM48_PDISC_RR; |
| si1->header.skip_indicator = 0; |
| si1->header.system_information = GSM48_MT_RR_SYSINFO_1; |
| |
| rc = generate_cell_chan_list(si1->cell_channel_description, bts); |
| if (rc < 0) |
| return rc; |
| |
| si1->rach_control = bts->si_common.rach_control; |
| |
| /* SI1 Rest Octets (10.5.2.32), contains NCH position */ |
| rc = rest_octets_si1(si1->rest_octets, NULL); |
| |
| return sizeof(*si1) + rc; |
| } |
| |
| static int generate_si2(uint8_t *output, struct gsm_bts *bts) |
| { |
| int rc; |
| struct gsm48_system_information_type_2 *si2 = |
| (struct gsm48_system_information_type_2 *) output; |
| |
| memset(si2, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN); |
| |
| si2->header.l2_plen = (22 << 2) | 1; |
| si2->header.rr_protocol_discriminator = GSM48_PDISC_RR; |
| si2->header.skip_indicator = 0; |
| si2->header.system_information = GSM48_MT_RR_SYSINFO_2; |
| |
| rc = generate_bcch_chan_list(si2->bcch_frequency_list, bts, 0); |
| if (rc < 0) |
| return rc; |
| |
| si2->ncc_permitted = bts->si_common.ncc_permitted; |
| si2->rach_control = bts->si_common.rach_control; |
| |
| return sizeof(*si2); |
| } |
| |
| static struct gsm48_si_ro_info si_info = { |
| .selection_params = { |
| .present = 0, |
| }, |
| .power_offset = { |
| .present = 0, |
| }, |
| .si2ter_indicator = 0, |
| .early_cm_ctrl = 1, |
| .scheduling = { |
| .present = 0, |
| }, |
| .gprs_ind = { |
| .si13_position = 0, |
| .ra_colour = 0, |
| .present = 1, |
| }, |
| .lsa_params = { |
| .present = 0, |
| }, |
| .cell_id = 0, /* FIXME: doesn't the bts have this? */ |
| .break_ind = 0, |
| }; |
| |
| static int generate_si3(uint8_t *output, struct gsm_bts *bts) |
| { |
| int rc; |
| struct gsm48_system_information_type_3 *si3 = |
| (struct gsm48_system_information_type_3 *) output; |
| |
| memset(si3, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN); |
| |
| si3->header.l2_plen = (18 << 2) | 1; |
| si3->header.rr_protocol_discriminator = GSM48_PDISC_RR; |
| si3->header.skip_indicator = 0; |
| si3->header.system_information = GSM48_MT_RR_SYSINFO_3; |
| |
| si3->cell_identity = htons(bts->cell_identity); |
| gsm48_generate_lai(&si3->lai, bts->network->country_code, |
| bts->network->network_code, |
| bts->location_area_code); |
| si3->control_channel_desc = bts->si_common.chan_desc; |
| si3->cell_options = bts->si_common.cell_options; |
| si3->cell_sel_par = bts->si_common.cell_sel_par; |
| si3->rach_control = bts->si_common.rach_control; |
| |
| /* SI3 Rest Octets (10.5.2.34), containing |
| CBQ, CELL_RESELECT_OFFSET, TEMPORARY_OFFSET, PENALTY_TIME |
| Power Offset, 2ter Indicator, Early Classmark Sending, |
| Scheduling if and WHERE, GPRS Indicator, SI13 position */ |
| rc = rest_octets_si3(si3->rest_octets, &si_info); |
| |
| return sizeof(*si3) + rc; |
| } |
| |
| static int generate_si4(uint8_t *output, struct gsm_bts *bts) |
| { |
| int rc; |
| struct gsm48_system_information_type_4 *si4 = |
| (struct gsm48_system_information_type_4 *) output; |
| |
| /* length of all IEs present except SI4 rest octets and l2_plen */ |
| int l2_plen = sizeof(*si4) - 1; |
| |
| memset(si4, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN); |
| |
| si4->header.rr_protocol_discriminator = GSM48_PDISC_RR; |
| si4->header.skip_indicator = 0; |
| si4->header.system_information = GSM48_MT_RR_SYSINFO_4; |
| |
| gsm48_generate_lai(&si4->lai, bts->network->country_code, |
| bts->network->network_code, |
| bts->location_area_code); |
| si4->cell_sel_par = bts->si_common.cell_sel_par; |
| si4->rach_control = bts->si_common.rach_control; |
| |
| /* Optional: CBCH Channel Description + CBCH Mobile Allocation */ |
| |
| si4->header.l2_plen = (l2_plen << 2) | 1; |
| |
| /* SI4 Rest Octets (10.5.2.35), containing |
| Optional Power offset, GPRS Indicator, |
| Cell Identity, LSA ID, Selection Parameter */ |
| rc = rest_octets_si4(si4->data, &si_info); |
| |
| return sizeof(*si4) + rc; |
| } |
| |
| static int generate_si5(uint8_t *output, struct gsm_bts *bts) |
| { |
| struct gsm48_system_information_type_5 *si5; |
| int rc, l2_plen = 18; |
| |
| memset(output, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN); |
| |
| /* ip.access nanoBTS needs l2_plen!! */ |
| switch (bts->type) { |
| case GSM_BTS_TYPE_NANOBTS: |
| case GSM_BTS_TYPE_HSL_FEMTO: |
| *output++ = (l2_plen << 2) | 1; |
| l2_plen++; |
| break; |
| default: |
| break; |
| } |
| |
| si5 = (struct gsm48_system_information_type_5 *) output; |
| |
| /* l2 pseudo length, not part of msg: 18 */ |
| si5->rr_protocol_discriminator = GSM48_PDISC_RR; |
| si5->skip_indicator = 0; |
| si5->system_information = GSM48_MT_RR_SYSINFO_5; |
| rc = generate_bcch_chan_list(si5->bcch_frequency_list, bts, 1); |
| if (rc < 0) |
| return rc; |
| |
| /* 04.08 9.1.37: L2 Pseudo Length of 18 */ |
| return l2_plen; |
| } |
| |
| static int generate_si6(uint8_t *output, struct gsm_bts *bts) |
| { |
| struct gsm48_system_information_type_6 *si6; |
| int l2_plen = 11; |
| |
| memset(output, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN); |
| |
| /* ip.access nanoBTS needs l2_plen!! */ |
| switch (bts->type) { |
| case GSM_BTS_TYPE_NANOBTS: |
| case GSM_BTS_TYPE_HSL_FEMTO: |
| *output++ = (l2_plen << 2) | 1; |
| l2_plen++; |
| break; |
| default: |
| break; |
| } |
| |
| si6 = (struct gsm48_system_information_type_6 *) output; |
| |
| /* l2 pseudo length, not part of msg: 11 */ |
| si6->rr_protocol_discriminator = GSM48_PDISC_RR; |
| si6->skip_indicator = 0; |
| si6->system_information = GSM48_MT_RR_SYSINFO_6; |
| si6->cell_identity = htons(bts->cell_identity); |
| gsm48_generate_lai(&si6->lai, bts->network->country_code, |
| bts->network->network_code, |
| bts->location_area_code); |
| si6->cell_options = bts->si_common.cell_options; |
| si6->ncc_permitted = bts->si_common.ncc_permitted; |
| |
| /* SI6 Rest Octets: 10.5.2.35a: PCH / NCH info, VBS/VGCS options */ |
| |
| return l2_plen; |
| } |
| |
| static struct gsm48_si13_info si13_default = { |
| .cell_opts = { |
| .nmo = GPRS_NMO_II, |
| .t3168 = 2000, |
| .t3192 = 200, |
| .drx_timer_max = 3, |
| .bs_cv_max = 15, |
| .ext_info_present = 1, |
| .ext_info = { |
| /* The values below are just guesses ! */ |
| .egprs_supported = 0, |
| .use_egprs_p_ch_req = 1, |
| .bep_period = 5, |
| .pfc_supported = 0, |
| .dtm_supported = 0, |
| .bss_paging_coordination = 0, |
| }, |
| }, |
| .pwr_ctrl_pars = { |
| .alpha = 10, /* a = 1.0 */ |
| .t_avg_w = 16, |
| .t_avg_t = 16, |
| .pc_meas_chan = 0, /* downling measured on CCCH */ |
| .n_avg_i = 8, |
| }, |
| .bcch_change_mark = 1, |
| .si_change_field = 0, |
| .pbcch_present = 0, |
| { |
| .no_pbcch = { |
| .rac = 0, /* needs to be patched */ |
| .spgc_ccch_sup = 0, |
| .net_ctrl_ord = 0, |
| .prio_acc_thr = 6, |
| }, |
| }, |
| }; |
| |
| static int generate_si13(uint8_t *output, struct gsm_bts *bts) |
| { |
| struct gsm48_system_information_type_13 *si13 = |
| (struct gsm48_system_information_type_13 *) output; |
| int ret; |
| |
| memset(si13, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN); |
| |
| si13->header.rr_protocol_discriminator = GSM48_PDISC_RR; |
| si13->header.skip_indicator = 0; |
| si13->header.system_information = GSM48_MT_RR_SYSINFO_13; |
| |
| si13_default.no_pbcch.rac = bts->gprs.rac; |
| |
| ret = rest_octets_si13(si13->rest_octets, &si13_default); |
| if (ret < 0) |
| return ret; |
| |
| /* length is coded in bit 2 an up */ |
| si13->header.l2_plen = 0x01; |
| |
| return sizeof (*si13) + ret; |
| } |
| |
| typedef int (*gen_si_fn_t)(uint8_t *output, struct gsm_bts *bts); |
| |
| static const gen_si_fn_t gen_si_fn[_MAX_SYSINFO_TYPE] = { |
| [SYSINFO_TYPE_1] = &generate_si1, |
| [SYSINFO_TYPE_2] = &generate_si2, |
| [SYSINFO_TYPE_3] = &generate_si3, |
| [SYSINFO_TYPE_4] = &generate_si4, |
| [SYSINFO_TYPE_5] = &generate_si5, |
| [SYSINFO_TYPE_6] = &generate_si6, |
| [SYSINFO_TYPE_13] = &generate_si13, |
| }; |
| |
| int gsm_generate_si(struct gsm_bts *bts, enum osmo_sysinfo_type si_type) |
| { |
| gen_si_fn_t gen_si; |
| |
| switch (bts->gprs.mode) { |
| case BTS_GPRS_EGPRS: |
| si13_default.cell_opts.ext_info_present = 1; |
| si13_default.cell_opts.ext_info.egprs_supported = 1; |
| /* fallthrough */ |
| case BTS_GPRS_GPRS: |
| si_info.gprs_ind.present = 1; |
| break; |
| case BTS_GPRS_NONE: |
| si_info.gprs_ind.present = 0; |
| break; |
| } |
| |
| memcpy(&si_info.selection_params, |
| &bts->si_common.cell_ro_sel_par, |
| sizeof(struct gsm48_si_selection_params)); |
| |
| gen_si = gen_si_fn[si_type]; |
| if (!gen_si) |
| return -EINVAL; |
| |
| return gen_si(bts->si_buf[si_type], bts); |
| } |