/* 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 * (C) 2012 Holger Hans Peter Freyther * * 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 . * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * DCS1800 and PCS1900 have overlapping ARFCNs. We would need to set the * ARFCN_PCS flag on the 1900 ARFCNs but this would increase cell_alloc * and other arrays to make sure (ARFCN_PCS + 1024)/8 ARFCNs fit into the * array. DCS1800 and PCS1900 can not be used at the same time so conserve * memory and do the below. */ static int band_compatible(const struct gsm_bts *bts, int arfcn) { enum gsm_band band = gsm_arfcn2band(arfcn); /* normal case */ if (band == bts->band) return 1; /* deal with ARFCN_PCS not set */ if (band == GSM_BAND_1800 && bts->band == GSM_BAND_1900) return 1; return 0; } static int is_dcs_net(const struct gsm_bts *bts) { if (bts->band == GSM_BAND_850) return 0; if (bts->band == GSM_BAND_1900) return 0; return 1; } /* Return p(n) for given NR_OF_TDD_CELLS - see Table 9.1.54.1a, 3GPP TS 44.018 */ unsigned range1024_p(unsigned n) { switch (n) { case 0: return 0; case 1: return 10; case 2: return 19; case 3: return 28; case 4: return 36; case 5: return 44; case 6: return 52; case 7: return 60; case 8: return 67; case 9: return 74; case 10: return 81; case 11: return 88; case 12: return 95; case 13: return 102; case 14: return 109; case 15: return 116; case 16: return 122; default: return 0; } } /* Return q(m) for given NR_OF_TDD_CELLS - see Table 9.1.54.1b, 3GPP TS 44.018 */ unsigned range512_q(unsigned m) { switch (m) { case 0: return 0; case 1: return 9; case 2: return 17; case 3: return 25; case 4: return 32; case 5: return 39; case 6: return 46; case 7: return 53; case 8: return 59; case 9: return 65; case 10: return 71; case 11: return 77; case 12: return 83; case 13: return 89; case 14: return 95; case 15: return 101; case 16: return 106; case 17: return 111; case 18: return 116; case 19: return 121; case 20: return 126; default: return 0; } } unsigned earfcn_size(const struct osmo_earfcn_si2q *e) { /* account for all the constant bits in append_earfcn() */ return 25 + osmo_earfcn_bit_size(e); } unsigned uarfcn_size(const uint16_t *u, const uint16_t *sc, size_t u_len) { /*account for all the constant bits in append_uarfcn() */ return 29 + range1024_p(u_len); } bool si2q_size_check(const struct gsm_bts *bts) { const struct osmo_earfcn_si2q *e = &bts->si_common.si2quater_neigh_list; const uint16_t *u = bts->si_common.data.uarfcn_list, *sc = bts->si_common.data.scramble_list; size_t len = bts->si_common.uarfcn_length; unsigned e_sz = e ? earfcn_size(e) : 1, u_sz = len ? uarfcn_size(u, sc, len) : 1; /* 2 bits are used in between UARFCN and EARFCN structs */ if (SI2Q_MIN_LEN + u_sz + 2 + e_sz > SI2Q_MAX_LEN) return false; return true; } /* 3GPP TS 44.018, Table 9.1.54.1 - prepend diversity bit to scrambling code */ static inline uint16_t encode_fdd(uint16_t scramble, bool diversity) { if (diversity) return scramble | (1 << 9); return scramble; } int bts_uarfcn_del(struct gsm_bts *bts, uint16_t arfcn, uint16_t scramble) { uint16_t sc0 = encode_fdd(scramble, false), sc1 = encode_fdd(scramble, true), *ual = bts->si_common.data.uarfcn_list, *scl = bts->si_common.data.scramble_list; size_t len = bts->si_common.uarfcn_length, i; for (i = 0; i < len; i++) { if (arfcn == ual[i] && (sc0 == scl[i] || sc1 == scl[i])) { /* we rely on the assumption that (uarfcn, scramble) tuple is unique in the lists */ if (i != len - 1) { /* move the tail if necessary */ memmove(ual + i, ual + i + 1, 2 * (len - i + 1)); memmove(scl + i, scl + i + 1, 2 * (len - i + 1)); } break; } } if (i == len) return -EINVAL; bts->si_common.uarfcn_length--; return 0; } int bts_uarfcn_add(struct gsm_bts *bts, uint16_t arfcn, uint16_t scramble, bool diversity) { size_t len = bts->si_common.uarfcn_length, i, k; uint16_t scr, chk, *ual = bts->si_common.data.uarfcn_list, *scl = bts->si_common.data.scramble_list, scramble1 = encode_fdd(scramble, true), scramble0 = encode_fdd(scramble, false); scr = diversity ? scramble1 : scramble0; chk = diversity ? scramble0 : scramble1; if (len == MAX_EARFCN_LIST) return -ENOMEM; for (i = 0, k = 0; i < len; i++) { if (arfcn == ual[i] && (scr == scl[i] || chk == scl[i])) return -EADDRINUSE; if (scr > scl[i]) k = i + 1; } /* we keep lists sorted by scramble code: insert into appropriate position and move the tail */ if (len - k) { memmove(ual + k + 1, ual + k, (len - k) * 2); memmove(scl + k + 1, scl + k, (len - k) * 2); } ual[k] = arfcn; scl[k] = scr; bts->si_common.uarfcn_length++; if (si2q_size_check(bts)) return 0; bts_uarfcn_del(bts, arfcn, scramble); return -ENOSPC; } static inline int use_arfcn(const struct gsm_bts *bts, const bool bis, const bool ter, const bool pgsm, const int arfcn) { if (bts->force_combined_si) return !bis && !ter; if (!bis && !ter && band_compatible(bts, arfcn)) return 1; /* Correct but somehow broken with either the nanoBTS or the iPhone5 */ if (bis && pgsm && band_compatible(bts, arfcn) && (arfcn < 1 || arfcn > 124)) return 1; if (ter && !band_compatible(bts, arfcn)) return 1; return 0; } /* 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) & 1023) > 111) { LOGP(DRR, LOGL_ERROR, "arfcn(%u) > min(%u) + 111\n", arfcn, min_arfcn); return -EINVAL; } bitno = (arfcn - min_arfcn) & 1023; byte = bitno / 8; bit = bitno % 8; chan_list[2 + byte] |= 1 << (7 - bit); return 0; } /* generate a variable bitmap */ static inline int enc_freq_lst_var_bitmap(uint8_t *chan_list, struct bitvec *bv, const struct gsm_bts *bts, bool bis, bool ter, int min, bool pgsm) { int i; /* set it to 'Variable bitmap format' */ chan_list[0] = 0x8e; 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++) { /* see notes in bitvec2freq_list */ if (bitvec_get_bit_pos(bv, i) && ((!bis && !ter && band_compatible(bts,i)) || (bis && pgsm && band_compatible(bts,i) && (i < 1 || i > 124)) || (ter && !band_compatible(bts, i)))) { int rc = freq_list_bmrel_set_arfcn(chan_list, i); if (rc < 0) return rc; } } return 0; } /* generate a frequency list with the range 512 format */ static inline int enc_freq_lst_range(uint8_t *chan_list, struct bitvec *bv, const struct gsm_bts *bts, bool bis, bool ter, bool pgsm) { int arfcns[RANGE_ENC_MAX_ARFCNS]; int w[RANGE_ENC_MAX_ARFCNS]; int f0_included = 0; int arfcns_used = 0; int i, rc, range, f0; /* * Select ARFCNs according to the rules in bitvec2freq_list */ for (i = 0; i < bv->data_len * 8; ++i) { /* More ARFCNs than the maximum */ if (arfcns_used > ARRAY_SIZE(arfcns)) return -1; /* Check if we can select it? */ if (bitvec_get_bit_pos(bv, i) && use_arfcn(bts, bis, ter, pgsm, i)) arfcns[arfcns_used++] = i; } /* * Check if the given list of ARFCNs can be encoded. */ range = range_enc_determine_range(arfcns, arfcns_used, &f0); if (range == ARFCN_RANGE_INVALID) return -2; /* * Manipulate the ARFCN list according to the rules in J4 depending * on the selected range. */ arfcns_used = range_enc_filter_arfcns(arfcns, arfcns_used, f0, &f0_included); memset(w, 0, sizeof(w)); rc = range_enc_arfcns(range, arfcns, arfcns_used, w, 0); if (rc != 0) return -3; /* Select the range and the amount of bits needed */ switch (range) { case ARFCN_RANGE_128: return range_enc_range128(chan_list, f0, w); break; case ARFCN_RANGE_256: return range_enc_range256(chan_list, f0, w); break; case ARFCN_RANGE_512: return range_enc_range512(chan_list, f0, w); break; case ARFCN_RANGE_1024: return range_enc_range1024(chan_list, f0, f0_included, w); break; default: return -4; }; } /* 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, bool bis, bool ter) { int i, rc, min = -1, max = -1, arfcns = 0; bool pgsm = false; memset(chan_list, 0, 16); if (bts->band == GSM_BAND_900 && bts->c0->arfcn >= 1 && bts->c0->arfcn <= 124) pgsm = true; /* P-GSM-only handsets only support 'bit map 0 format' */ if (!bis && !ter && pgsm) { chan_list[0] = 0; for (i = 0; i < bv->data_len*8; i++) { if (i >= 1 && i <= 124 && bitvec_get_bit_pos(bv, i)) { rc = freq_list_bm0_set_arfcn(chan_list, i); if (rc < 0) return rc; } } return 0; } for (i = 0; i < bv->data_len*8; i++) { /* in case of SI2 or SI5 allow all neighbours in same band * in case of SI*bis, allow neighbours in same band ouside pgsm * in case of SI*ter, allow neighbours in different bands */ if (!bitvec_get_bit_pos(bv, i)) continue; if (!use_arfcn(bts, bis, ter, pgsm, i)) continue; /* count the arfcns we want to carry */ arfcns += 1; /* 955..1023 < 0..885 */ if (min < 0) min = i; if (i >= 955 && min < 955) min = i; if (i >= 955 && min >= 955 && i < min) min = i; if (i < 955 && min < 955 && i < min) min = i; if (max < 0) max = i; if (i < 955 && max >= 955) max = i; if (i >= 955 && max >= 955 && i > max) max = i; if (i < 955 && max < 955 && i > max) max = i; } if (max == -1) { /* Empty set, use 'bit map 0 format' */ chan_list[0] = 0; return 0; } /* Now find the best encoding */ if (((max - min) & 1023) <= 111) return enc_freq_lst_var_bitmap(chan_list, bv, bts, bis, ter, min, pgsm); /* Attempt to do the range encoding */ rc = enc_freq_lst_range(chan_list, bv, bts, bis, ter, pgsm); if (rc == 0) return 0; LOGP(DRR, LOGL_ERROR, "min_arfcn=%u, max_arfcn=%u, arfcns=%d " "can not generate ARFCN list", min, max, arfcns); return -EINVAL; } /* 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, false, false); } /* 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, bool si5, bool bis, bool ter) { 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, bis, ter); } static int list_arfcn(uint8_t *chan_list, uint8_t mask, char *text) { int n = 0, i; struct gsm_sysinfo_freq freq[1024]; memset(freq, 0, sizeof(freq)); gsm48_decode_freq_list(freq, chan_list, 16, 0xce, 1); for (i = 0; i < 1024; i++) { if (freq[i].mask) { if (!n) LOGP(DRR, LOGL_INFO, "%s", text); LOGPC(DRR, LOGL_INFO, " %d", i); n++; } } if (n) LOGPC(DRR, LOGL_INFO, "\n"); return n; } 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 = GSM48_LEN2PLEN(21); 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; list_arfcn(si1->cell_channel_description, 0xce, "Serving cell:"); si1->rach_control = bts->si_common.rach_control; /* * SI1 Rest Octets (10.5.2.32), contains NCH position and band * indicator but that is not in the 04.08. */ rc = rest_octets_si1(si1->rest_octets, NULL, is_dcs_net(bts)); 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 = GSM48_LEN2PLEN(22); 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, false, false, false); if (rc < 0) return rc; list_arfcn(si2->bcch_frequency_list, 0xce, "SI2 Neighbour cells in same band:"); si2->ncc_permitted = bts->si_common.ncc_permitted; si2->rach_control = bts->si_common.rach_control; return sizeof(*si2); } static int generate_si2bis(uint8_t *output, struct gsm_bts *bts) { int rc; struct gsm48_system_information_type_2bis *si2b = (struct gsm48_system_information_type_2bis *) output; int n; memset(si2b, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN); si2b->header.l2_plen = GSM48_LEN2PLEN(22); si2b->header.rr_protocol_discriminator = GSM48_PDISC_RR; si2b->header.skip_indicator = 0; si2b->header.system_information = GSM48_MT_RR_SYSINFO_2bis; rc = generate_bcch_chan_list(si2b->bcch_frequency_list, bts, false, true, false); if (rc < 0) return rc; n = list_arfcn(si2b->bcch_frequency_list, 0xce, "Neighbour cells in same band, but outside P-GSM:"); if (n) { /* indicate in SI2 and SI2bis: there is an extension */ struct gsm48_system_information_type_2 *si2 = (struct gsm48_system_information_type_2 *) bts->si_buf[SYSINFO_TYPE_2]; si2->bcch_frequency_list[0] |= 0x20; si2b->bcch_frequency_list[0] |= 0x20; } else bts->si_valid &= ~(1 << SYSINFO_TYPE_2bis); si2b->rach_control = bts->si_common.rach_control; return sizeof(*si2b); } static int generate_si2ter(uint8_t *output, struct gsm_bts *bts) { int rc; struct gsm48_system_information_type_2ter *si2t = (struct gsm48_system_information_type_2ter *) output; int n; memset(si2t, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN); si2t->header.l2_plen = GSM48_LEN2PLEN(22); si2t->header.rr_protocol_discriminator = GSM48_PDISC_RR; si2t->header.skip_indicator = 0; si2t->header.system_information = GSM48_MT_RR_SYSINFO_2ter; rc = generate_bcch_chan_list(si2t->ext_bcch_frequency_list, bts, false, false, true); if (rc < 0) return rc; n = list_arfcn(si2t->ext_bcch_frequency_list, 0x8e, "Neighbour cells in different band:"); if (!n) bts->si_valid &= ~(1 << SYSINFO_TYPE_2ter); return sizeof(*si2t); } static int generate_si2quater(uint8_t *output, struct gsm_bts *bts) { int rc, i = MAX_EARFCN_LIST; struct gsm48_system_information_type_2quater *si2q = (struct gsm48_system_information_type_2quater *) output; memset(si2q, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN); si2q->header.l2_plen = GSM48_LEN2PLEN(22); si2q->header.rr_protocol_discriminator = GSM48_PDISC_RR; si2q->header.skip_indicator = 0; si2q->header.system_information = GSM48_MT_RR_SYSINFO_2quater; rc = rest_octets_si2quater(si2q->rest_octets, &bts->si_common.si2quater_neigh_list, bts->si_common.data.uarfcn_list, bts->si_common.data.scramble_list, bts->si_common.uarfcn_length); if (rc < 0) return rc; if (bts->si_common.si2quater_neigh_list.arfcn) for (i = 0; i < MAX_EARFCN_LIST; i++) if (bts->si_common.si2quater_neigh_list.arfcn[i] != OSMO_EARFCN_INVALID) break; if (!bts->si_common.uarfcn_length && i == MAX_EARFCN_LIST) bts->si_valid &= ~(1 << SYSINFO_TYPE_2quater); return sizeof(*si2q) + rc; } 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, }, .si2quater_indicator = 0, .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 = GSM48_LEN2PLEN(18); 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; /* allow/disallow DTXu */ gsm48_set_dtx(&si3->cell_options, bts->dtxu, bts->dtxu, true); if ((bts->si_valid & (1 << SYSINFO_TYPE_2ter))) { LOGP(DRR, LOGL_INFO, "SI 2ter is included.\n"); si_info.si2ter_indicator = 1; } else { si_info.si2ter_indicator = 0; } if ((bts->si_valid & (1 << SYSINFO_TYPE_2quater))) { LOGP(DRR, LOGL_INFO, "SI 2quater is included.\n"); si_info.si2quater_indicator = 1; } else { si_info.si2quater_indicator = 0; } si_info.early_cm_ctrl = bts->early_classmark_allowed; /* 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; struct gsm_lchan *cbch_lchan; uint8_t *restoct = si4->data; /* 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 */ cbch_lchan = gsm_bts_get_cbch(bts); if (cbch_lchan) { struct gsm48_chan_desc cd; gsm48_lchan2chan_desc(&cd, cbch_lchan); tv_fixed_put(si4->data, GSM48_IE_CBCH_CHAN_DESC, 3, (uint8_t *) &cd); l2_plen += 3 + 1; restoct += 3 + 1; /* we don't use hopping and thus don't need a CBCH MA */ } si4->header.l2_plen = GSM48_LEN2PLEN(l2_plen); /* SI4 Rest Octets (10.5.2.35), containing Optional Power offset, GPRS Indicator, Cell Identity, LSA ID, Selection Parameter */ rc = rest_octets_si4(restoct, &si_info, output + GSM_MACBLOCK_LEN - restoct); return l2_plen + 1 + 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_OSMO_SYSMO: *output++ = GSM48_LEN2PLEN(l2_plen); 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, true, false, false); if (rc < 0) return rc; list_arfcn(si5->bcch_frequency_list, 0xce, "SI5 Neighbour cells in same band:"); /* 04.08 9.1.37: L2 Pseudo Length of 18 */ return l2_plen; } static int generate_si5bis(uint8_t *output, struct gsm_bts *bts) { struct gsm48_system_information_type_5bis *si5b; int rc, l2_plen = 18; int n; 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_OSMO_SYSMO: *output++ = GSM48_LEN2PLEN(l2_plen); l2_plen++; break; default: break; } si5b = (struct gsm48_system_information_type_5bis *) output; /* l2 pseudo length, not part of msg: 18 */ si5b->rr_protocol_discriminator = GSM48_PDISC_RR; si5b->skip_indicator = 0; si5b->system_information = GSM48_MT_RR_SYSINFO_5bis; rc = generate_bcch_chan_list(si5b->bcch_frequency_list, bts, true, true, false); if (rc < 0) return rc; n = list_arfcn(si5b->bcch_frequency_list, 0xce, "Neighbour cells in same band, but outside P-GSM:"); if (n) { /* indicate in SI5 and SI5bis: there is an extension */ struct gsm48_system_information_type_5 *si5 = (struct gsm48_system_information_type_5 *) bts->si_buf[SYSINFO_TYPE_5]; si5->bcch_frequency_list[0] |= 0x20; si5b->bcch_frequency_list[0] |= 0x20; } else bts->si_valid &= ~(1 << SYSINFO_TYPE_5bis); /* 04.08 9.1.37: L2 Pseudo Length of 18 */ return l2_plen; } static int generate_si5ter(uint8_t *output, struct gsm_bts *bts) { struct gsm48_system_information_type_5ter *si5t; int rc, l2_plen = 18; int n; 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_OSMO_SYSMO: *output++ = GSM48_LEN2PLEN(l2_plen); l2_plen++; break; default: break; } si5t = (struct gsm48_system_information_type_5ter *) output; /* l2 pseudo length, not part of msg: 18 */ si5t->rr_protocol_discriminator = GSM48_PDISC_RR; si5t->skip_indicator = 0; si5t->system_information = GSM48_MT_RR_SYSINFO_5ter; rc = generate_bcch_chan_list(si5t->bcch_frequency_list, bts, true, false, true); if (rc < 0) return rc; n = list_arfcn(si5t->bcch_frequency_list, 0x8e, "Neighbour cells in different band:"); if (!n) bts->si_valid &= ~(1 << SYSINFO_TYPE_5ter); /* 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; int rc; 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_OSMO_SYSMO: *output++ = GSM48_LEN2PLEN(l2_plen); 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; /* allow/disallow DTXu */ gsm48_set_dtx(&si6->cell_options, bts->dtxu, bts->dtxu, false); /* SI6 Rest Octets: 10.5.2.35a: PCH / NCH info, VBS/VGCS options */ rc = rest_octets_si6(si6->rest_octets, is_dcs_net(bts)); return l2_plen + rc; } static struct gsm48_si13_info si13_default = { .cell_opts = { .nmo = GPRS_NMO_II, .t3168 = 2000, .t3192 = 1500, .drx_timer_max = 3, .bs_cv_max = 15, .ctrl_ack_type_use_block = true, .ext_info_present = 0, .supports_egprs_11bit_rach = 0, .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 = 0, /* a = 0.0 */ .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; si13_default.no_pbcch.net_ctrl_ord = bts->gprs.net_ctrl_ord; si13_default.cell_opts.ctrl_ack_type_use_block = bts->gprs.ctrl_ack_type_use_block; /* Information about the other SIs */ si13_default.bcch_change_mark = bts->bcch_change_mark; si13_default.cell_opts.supports_egprs_11bit_rach = bts->gprs.supports_egprs_11bit_rach; 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_2bis] = &generate_si2bis, [SYSINFO_TYPE_2ter] = &generate_si2ter, [SYSINFO_TYPE_2quater] = &generate_si2quater, [SYSINFO_TYPE_3] = &generate_si3, [SYSINFO_TYPE_4] = &generate_si4, [SYSINFO_TYPE_5] = &generate_si5, [SYSINFO_TYPE_5bis] = &generate_si5bis, [SYSINFO_TYPE_5ter] = &generate_si5ter, [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); }