/* 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 #include #include #include #include struct gsm0808_cell_id_list2; /* * 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; if (gsm_arfcn2band_rc(arfcn, &band) < 0) { LOGP(DRR, LOGL_ERROR, "Invalid arfcn %d detected!\n", arfcn); return 0; } /* 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; } } size_t si2q_earfcn_count(const struct osmo_earfcn_si2q *e) { unsigned i, ret = 0; if (!e) return 0; for (i = 0; i < e->length; i++) if (e->arfcn[i] != OSMO_EARFCN_INVALID) ret++; return ret; } /* generate SI2quater messages, return rest octets length of last generated message or negative error code */ static int make_si2quaters(struct gsm_bts *bts, bool counting) { int rc; bool memory_exceeded = true; struct gsm48_system_information_type_2quater *si2q; for (bts->si2q_index = 0; bts->si2q_index < SI2Q_MAX_NUM; bts->si2q_index++) { si2q = GSM_BTS_SI2Q(bts, bts->si2q_index); if (counting) { /* that's legitimate if we're called for counting purpose: */ if (bts->si2q_count < bts->si2q_index) bts->si2q_count = bts->si2q_index; } else { 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); if (rc < 0) return rc; if (bts->u_offset >= bts->si_common.uarfcn_length && bts->e_offset >= si2q_earfcn_count(&bts->si_common.si2quater_neigh_list)) { memory_exceeded = false; break; } } if (memory_exceeded) return -ENOMEM; return rc; } /* we generate SI2q rest octets twice to get proper estimation but it's one time cost anyway */ uint8_t si2q_num(struct gsm_bts *bts) { int rc = make_si2quaters(bts, true); uint8_t num = bts->si2q_index + 1; /* number of SI2quater messages */ /* N. B: si2q_num() should NEVER be called during actual SI2q rest octets generation we're not re-entrant because of the following code: */ bts->u_offset = 0; bts->e_offset = 0; if (rc < 0) return 0xFF; /* return impossible index as an indicator of error in generating SI2quater */ return num; } /* 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_earfcn_add(struct gsm_bts *bts, uint16_t earfcn, uint8_t thresh_hi, uint8_t thresh_lo, uint8_t prio, uint8_t qrx, uint8_t meas_bw) { struct osmo_earfcn_si2q *e = &bts->si_common.si2quater_neigh_list; int r = osmo_earfcn_add(e, earfcn, (meas_bw < EARFCN_MEAS_BW_INVALID) ? meas_bw : OSMO_EARFCN_MEAS_INVALID); if (r < 0) return r; if (e->thresh_hi && thresh_hi != e->thresh_hi) r = 1; e->thresh_hi = thresh_hi; if (thresh_lo != EARFCN_THRESH_LOW_INVALID) { if (e->thresh_lo_valid && e->thresh_lo != thresh_lo) r = EARFCN_THRESH_LOW_INVALID; e->thresh_lo = thresh_lo; e->thresh_lo_valid = true; } if (qrx != EARFCN_QRXLV_INVALID) { if (e->qrxlm_valid && e->qrxlm != qrx) r = EARFCN_QRXLV_INVALID + 1; e->qrxlm = qrx; e->qrxlm_valid = true; } if (prio != EARFCN_PRIO_INVALID) { if (e->prio_valid && e->prio != prio) r = EARFCN_PRIO_INVALID; e->prio = prio; e->prio_valid = true; } return r; } /* Scrambling Code as defined in 3GPP TS 25.213 is 9 bit long so number below is unreacheable upper bound */ #define SC_BOUND 600 /* Find position for a given UARFCN (take SC into consideration if it's available) in a sorted list N. B: we rely on the assumption that (uarfcn, scramble) tuple is unique in the lists */ static int uarfcn_sc_pos(const struct gsm_bts *bts, uint16_t uarfcn, uint16_t scramble) { const uint16_t *sc = bts->si_common.data.scramble_list; uint16_t i, scramble0 = encode_fdd(scramble, false), scramble1 = encode_fdd(scramble, true); for (i = 0; i < bts->si_common.uarfcn_length; i++) if (uarfcn == bts->si_common.data.uarfcn_list[i]) { if (scramble < SC_BOUND) { if (scramble0 == sc[i] || scramble1 == sc[i]) return i; } else return i; } return -1; } int bts_uarfcn_del(struct gsm_bts *bts, uint16_t arfcn, uint16_t scramble) { uint16_t *ual = bts->si_common.data.uarfcn_list, *scl = bts->si_common.data.scramble_list; size_t len = bts->si_common.uarfcn_length; int pos = uarfcn_sc_pos(bts, arfcn, scramble); if (pos < 0) return -EINVAL; if (pos != len - 1) { /* move the tail if necessary */ memmove(ual + pos, ual + pos + 1, 2 * (len - pos + 1)); memmove(scl + pos, scl + pos + 1, 2 * (len - pos + 1)); } 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; uint8_t si2q; int pos = uarfcn_sc_pos(bts, arfcn, scramble); uint16_t scr = diversity ? encode_fdd(scramble, true) : encode_fdd(scramble, false), *ual = bts->si_common.data.uarfcn_list, *scl = bts->si_common.data.scramble_list; if (len == MAX_EARFCN_LIST) return -ENOMEM; if (pos >= 0) return -EADDRINUSE; /* find the suitable position for arfcn if any */ pos = uarfcn_sc_pos(bts, arfcn, SC_BOUND); i = (pos < 0) ? len : pos; /* move the tail to make space for inserting if necessary */ if (i < len) { memmove(ual + i + 1, ual + i, (len - i) * 2); memmove(scl + i + 1, scl + i, (len - i) * 2); } /* insert into appropriate position */ ual[i] = arfcn; scl[i] = scr; bts->si_common.uarfcn_length++; /* try to generate SI2q */ si2q = si2q_num(bts); if (si2q <= SI2Q_MAX_NUM) { bts->si2q_count = si2q - 1; return 0; } /* rollback after unsuccessful generation */ 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_set ? bts->force_combined_si : bts->model->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; } int range_encode(enum gsm48_range r, int *arfcns, int arfcns_used, int *w, int f0, uint8_t *chan_list) { /* * Manipulate the ARFCN list according to the rules in J4 depending * on the selected range. */ int rc, f0_included; range_enc_filter_arfcns(arfcns, arfcns_used, f0, &f0_included); rc = range_enc_arfcns(r, arfcns, arfcns_used, w, 0); if (rc < 0) return rc; /* Select the range and the amount of bits needed */ switch (r) { case ARFCN_RANGE_128: return range_enc_range128(chan_list, f0, w); case ARFCN_RANGE_256: return range_enc_range256(chan_list, f0, w); case ARFCN_RANGE_512: return range_enc_range512(chan_list, f0, w); case ARFCN_RANGE_1024: return range_enc_range1024(chan_list, f0, f0_included, w); default: return -ERANGE; }; return f0_included; } /* 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 arfcns_used = 0; int i, 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; memset(w, 0, sizeof(w)); return range_encode(range, arfcns, arfcns_used, w, f0, chan_list); } /* 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\n", 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); } struct generate_bcch_chan_list__ni_iter_data { struct gsm_bts *bts; struct bitvec *bv; }; static bool generate_bcch_chan_list__ni_iter_cb(const struct neighbor_ident_key *key, const struct gsm0808_cell_id_list2 *val, void *cb_data) { struct generate_bcch_chan_list__ni_iter_data *data = cb_data; if (key->from_bts != NEIGHBOR_IDENT_KEY_ANY_BTS && key->from_bts != data->bts->nr) return true; bitvec_set_bit_pos(data->bv, key->arfcn, 1); return true; } /*! generate a cell channel list as per Section 10.5.2.22 of 04.08 * \param[out] chan_list caller-provided output buffer * \param[in] bts BTS descriptor used for input data * \param[in] si5 Are we generating SI5xxx (true) or SI2xxx (false) * \param[in] bis Are we generating SIXbis (true) or not (false) * \param[in] ter Are we generating SIXter (true) or not (false) */ 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; int rc; /* first we generate a bitvec of the BCCH ARFCN's in our BSC */ 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); if (llist_empty(&bts->local_neighbors)) { /* There are no explicit neighbors, assume all BTS are. */ 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); } } else { /* Only add explicit neighbor cells */ struct gsm_bts_ref *neigh; llist_for_each_entry(neigh, &bts->local_neighbors, entry) { bitvec_set_bit_pos(bv, neigh->bts->c0->arfcn, 1); } } /* Also add neighboring BSS cells' ARFCNs */ { struct generate_bcch_chan_list__ni_iter_data data = { .bv = bv, .bts = bts, }; neighbor_ident_iter(bts->network->neighbor_bss_cells, generate_bcch_chan_list__ni_iter_cb, &data); } } /* then we generate a GSM 04.08 frequency list from the bitvec */ rc = bitvec2freq_list(chan_list, bv, bts, bis, ter); if (rc < 0) return rc; /* Set BA-IND depending on whether we're generating SI2 or SI5. * The point here is to be able to correlate whether a given MS * measurement report was using the neighbor cells advertised in * SI2 or in SI5, as those two could very well be different */ if (si5) chan_list[0] |= 0x10; else chan_list[0] &= ~0x10; return rc; } 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(enum osmo_sysinfo_type t, struct gsm_bts *bts) { int rc; struct gsm48_system_information_type_1 *si1 = (struct gsm48_system_information_type_1 *) GSM_BTS_SI(bts, t); 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; if (acc_ramp_is_enabled(&bts->acc_ramp)) acc_ramp_apply(&si1->rach_control, &bts->acc_ramp); /* * 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(enum osmo_sysinfo_type t, struct gsm_bts *bts) { int rc; struct gsm48_system_information_type_2 *si2 = (struct gsm48_system_information_type_2 *) GSM_BTS_SI(bts, t); 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; if (acc_ramp_is_enabled(&bts->acc_ramp)) acc_ramp_apply(&si2->rach_control, &bts->acc_ramp); return sizeof(*si2); } static int generate_si2bis(enum osmo_sysinfo_type t, struct gsm_bts *bts) { int rc; struct gsm48_system_information_type_2bis *si2b = (struct gsm48_system_information_type_2bis *) GSM_BTS_SI(bts, t); int n; memset(si2b, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN); si2b->header.l2_plen = GSM48_LEN2PLEN(21); 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, "SI2bis 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 *) GSM_BTS_SI(bts, 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; if (acc_ramp_is_enabled(&bts->acc_ramp)) acc_ramp_apply(&si2b->rach_control, &bts->acc_ramp); /* SI2bis Rest Octets as per 3GPP TS 44.018 §10.5.2.33 */ rc = rest_octets_si2bis(si2b->rest_octets); return sizeof(*si2b) + rc; } static int generate_si2ter(enum osmo_sysinfo_type t, struct gsm_bts *bts) { int rc; struct gsm48_system_information_type_2ter *si2t = (struct gsm48_system_information_type_2ter *) GSM_BTS_SI(bts, t); int n; memset(si2t, GSM_MACBLOCK_PADDING, GSM_MACBLOCK_LEN); si2t->header.l2_plen = GSM48_LEN2PLEN(18); 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, "SI2ter Neighbour cells in different band:"); if (!n) bts->si_valid &= ~(1 << SYSINFO_TYPE_2ter); /* SI2ter Rest Octets as per 3GPP TS 44.018 §10.5.2.33a */ rc = rest_octets_si2ter(si2t->rest_octets); return sizeof(*si2t) + rc; } /* SI2quater messages are optional - we only generate them when neighbor UARFCNs or EARFCNs are configured */ static inline bool si2quater_not_needed(struct gsm_bts *bts) { unsigned i = MAX_EARFCN_LIST; 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); /* mark SI2q as invalid if no (E|U)ARFCNs are present */ return true; } return false; } static int generate_si2quater(enum osmo_sysinfo_type t, struct gsm_bts *bts) { int rc; struct gsm48_system_information_type_2quater *si2q; if (si2quater_not_needed(bts)) /* generate rest_octets for SI2q only when necessary */ return GSM_MACBLOCK_LEN; bts->u_offset = 0; bts->e_offset = 0; bts->si2q_index = 0; bts->si2q_count = si2q_num(bts) - 1; rc = make_si2quaters(bts, false); if (rc < 0) return rc; OSMO_ASSERT(bts->si2q_count == bts->si2q_index); OSMO_ASSERT(bts->si2q_count <= SI2Q_MAX_NUM); return sizeof(*si2q) + rc; } static struct gsm48_si_ro_info si_info = { .selection_params = { .present = 0, }, .power_offset = { .present = 0, }, .si2ter_indicator = false, .early_cm_ctrl = true, .scheduling = { .present = 0, }, .gprs_ind = { .si13_position = 0, .ra_colour = 0, .present = 1, }, .early_cm_restrict_3g = false, .si2quater_indicator = false, .lsa_params = { .present = 0, }, .cell_id = 0, /* FIXME: doesn't the bts have this? */ .break_ind = 0, }; static int generate_si3(enum osmo_sysinfo_type t, struct gsm_bts *bts) { int rc; struct gsm48_system_information_type_3 *si3 = (struct gsm48_system_information_type_3 *) GSM_BTS_SI(bts, t); 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_lai2(&si3->lai, bts_lai(bts)); 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; if (acc_ramp_is_enabled(&bts->acc_ramp)) acc_ramp_apply(&si3->rach_control, &bts->acc_ramp); /* allow/disallow DTXu */ gsm48_set_dtx(&si3->cell_options, bts->dtxu, bts->dtxu, true); if (GSM_BTS_HAS_SI(bts, SYSINFO_TYPE_2ter)) { LOGP(DRR, LOGL_INFO, "SI 2ter is included.\n"); si_info.si2ter_indicator = true; } else { si_info.si2ter_indicator = false; } if (GSM_BTS_HAS_SI(bts, SYSINFO_TYPE_2quater)) { LOGP(DRR, LOGL_INFO, "SI 2quater is included, based on %zu EARFCNs and %zu UARFCNs.\n", si2q_earfcn_count(&bts->si_common.si2quater_neigh_list), bts->si_common.uarfcn_length); si_info.si2quater_indicator = true; } else { si_info.si2quater_indicator = false; } si_info.early_cm_ctrl = bts->early_classmark_allowed; si_info.early_cm_restrict_3g = !bts->early_classmark_allowed_3g; /* 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(enum osmo_sysinfo_type t, struct gsm_bts *bts) { int rc; struct gsm48_system_information_type_4 *si4 = (struct gsm48_system_information_type_4 *) GSM_BTS_SI(bts, t); 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_lai2(&si4->lai, bts_lai(bts)); si4->cell_sel_par = bts->si_common.cell_sel_par; si4->rach_control = bts->si_common.rach_control; if (acc_ramp_is_enabled(&bts->acc_ramp)) acc_ramp_apply(&si4->rach_control, &bts->acc_ramp); /* 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_as_configured(&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, (uint8_t *)GSM_BTS_SI(bts, t) + GSM_MACBLOCK_LEN - restoct); return l2_plen + 1 + rc; } static int generate_si5(enum osmo_sysinfo_type t, struct gsm_bts *bts) { struct gsm48_system_information_type_5 *si5; uint8_t *output = GSM_BTS_SI(bts, t); 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_OSMOBTS: *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(enum osmo_sysinfo_type t, struct gsm_bts *bts) { struct gsm48_system_information_type_5bis *si5b; uint8_t *output = GSM_BTS_SI(bts, t); 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_OSMOBTS: *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, "SI5bis 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 *) GSM_BTS_SI(bts, SYSINFO_TYPE_5)+1; 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(enum osmo_sysinfo_type t, struct gsm_bts *bts) { struct gsm48_system_information_type_5ter *si5t; uint8_t *output = GSM_BTS_SI(bts, t); 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_OSMOBTS: *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, "SI5ter 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(enum osmo_sysinfo_type t, struct gsm_bts *bts) { struct gsm48_system_information_type_6 *si6; uint8_t *output = GSM_BTS_SI(bts, t); 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_OSMOBTS: *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_lai2(&si6->lai, bts_lai(bts)); 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, .rac = 0, /* needs to be patched */ .spgc_ccch_sup = 0, .net_ctrl_ord = 0, .prio_acc_thr = 6, }; static int generate_si13(enum osmo_sysinfo_type t, struct gsm_bts *bts) { struct gsm48_system_information_type_13 *si13 = (struct gsm48_system_information_type_13 *) GSM_BTS_SI(bts, t); 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.rac = bts->gprs.rac; si13_default.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)(enum osmo_sysinfo_type t, 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) { int rc; 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) { LOGP(DRR, LOGL_ERROR, "bts %u: no gen_si_fn() for SI%s\n", bts->nr, get_value_string(osmo_sitype_strs, si_type)); return -EINVAL; } rc = gen_si(si_type, bts); if (rc < 0) LOGP(DRR, LOGL_ERROR, "bts %u: Error while generating SI%s: %s (%d)\n", bts->nr, get_value_string(osmo_sitype_strs, si_type), strerror(-rc), rc); return rc; }