/* * (C) 2022 by sysmocom - s.f.m.c. GmbH * Author: Philipp Maier * All Rights Reserved * * SPDX-License-Identifier: GPL-2.0+ * * 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. * */ #include #include #include #include #include #include #include #include #include #include #define E1_TRAU_BITS_MSGB 2048 /* CRC polynom for CS1 TRAU frame protection: X^16+X^12+X^5+1 */ const struct osmo_crc16gen_code cs1_crc16 = { 16, 0x1021, 0, 0xffff }; /* Frame Type C-bits: C1..C5 */ #define PCU_TRAU_ER_FT_PCU_SYNC_IND 0x0F #define PCU_TRAU_ER_FT_CCU_SYNC_IND 0x15 #define PCU_TRAU_ER_FT_DATA_IND 0x1A #define PCU_TRAU_ER_FT_DATA9_IND 0x04 const ubit_t T_bits_16[] = { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* (+8 variable bits) */ }; const ubit_t T_bits_64[] = { 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* (+16 variable bits) */ }; /* Calc an odd parity bit over a given number of bits */ static ubit_t calc_parity(const ubit_t *bits, size_t len) { size_t i; ubit_t par = 1; for (i = 0; i < len; i++) par ^= bits[i]; return par; } /* Put data to TRAU frame, skip T bits */ static int put_trau_data(ubit_t *bits, size_t bits_len, const ubit_t *bits_map, size_t bits_map_len, const ubit_t *bits_in, size_t offs, size_t len) { size_t bit_count = 0; size_t i = 0; /* The bits map must always cover all bits, so it must not be shorter * then the bits we are about to parse. Also the offset must not be * greater then the length of the bits */ if (bits_len > bits_map_len) return -EINVAL; if (bits_len <= offs) return -EINVAL; /* Advance to the position where the data is stored */ bits += offs; bits_len -= offs; bits_map += offs; bits_map_len -= offs; do { /* Do not exceed bits or bits_map */ if (bit_count > bits_len) return -EINVAL; if (bit_count > bits_map_len) return -EINVAL; /* Do not exceed output buffer */ if (i > bits_len) return -EINVAL; /* skip positions that have already bits set. */ if (*bits_map == 0) { *bits = *bits_in; bits_in++; i++; } bit_count++; bits++; bits_map++; } while (i < len); return 0; } /* Put an uint32 value to TRAU frame */ static int put_trau_uint32(ubit_t *bits, size_t bits_len, const ubit_t *bits_map, size_t bits_map_len, uint32_t value, size_t offs, size_t len) { ubit_t buf[32]; OSMO_ASSERT(len < 32); memset(buf, 0, sizeof(buf)); value = htonl(value); osmo_pbit2ubit_ext(buf, 0, (ubit_t *) &value, 32 - len, len, 0); return put_trau_data(bits, bits_len, bits_map, bits_map_len, buf, offs, len); } /* Get data from TRAU frame, ignore T bits */ static int get_trau_data(ubit_t *bits_out, size_t bits_out_len, const ubit_t *bits, size_t bits_len, const ubit_t *bits_map, size_t bits_map_len, size_t offs, size_t len) { size_t bit_count = 0; size_t i = 0; /* (see above) */ if (bits_len > bits_map_len) return -EINVAL; if (bits_len <= offs) return -EINVAL; /* Advance to the position where the data is located */ bits += offs; bits_map += offs; bits_len -= offs; bits_map_len -= offs; /* Extract bits from TRAU frame */ do { /* Do not exceed bits or bits_map */ if (bit_count > bits_len) return -EINVAL; if (bit_count > bits_map_len) return -EINVAL; /* Do not exceed output buffer */ if (i > bits_out_len) return -EINVAL; if (*bits_map == 0) { *bits_out = *bits; bits_out++; i++; } bit_count++; bits++; bits_map++; } while (i < len); return 0; } /* Get an uint32 value from TRAU frame */ static uint32_t get_trau_uint32(const ubit_t *bits, size_t bits_len, const ubit_t *bits_map, size_t bits_map_len, size_t offs, uint8_t len) { ubit_t buf[32]; uint32_t result = 0; int rc; OSMO_ASSERT(len < 32); memset(buf, 0, sizeof(buf)); rc = get_trau_data(buf, sizeof(buf), bits, bits_len, bits_map, bits_map_len, offs, len); if (rc < 0) return 0; osmo_ubit2pbit_ext((pbit_t *) &result, 32 - len, buf, 0, len, 0); result = ntohl(result); return result; } /* Set Time adjustment bits, add 4 more bits in case of delay */ static int set_timing_ajustment_bits_16(ubit_t *trau_bits, enum time_adj_val tav) { /* Note: This sets the tail bits and returns the final length of the final length of the TRAU frame. The caller * must then make sure that the frame is transitted with the returned length to achieve correct timing * alignment. */ switch (tav) { case TIME_ADJ_NONE: return 320; case TIME_ADJ_DELAY_250us: return 320 + 4; case TIME_ADJ_ADVANCE_250us: /* Note: the 16 removed bits are not transmitted. */ return 320 - 4; } return -EINVAL; } /* Set Time adjustment bits, add 16 more bits in case of delay */ static int set_timing_ajustment_bits_64(ubit_t *trau_bits, enum time_adj_val tav) { /* (see comment above) */ switch (tav) { case TIME_ADJ_NONE: return 1280; case TIME_ADJ_DELAY_250us: return 1280 + 16; case TIME_ADJ_ADVANCE_250us: /* Note: the 16 removed bits are not transmitted. */ return 1280 - 16; } return -EINVAL; } /* Decode an 8-byte access burst data structure */ static int decode_ab(struct er_gprs_ab *ab, uint8_t *ab_bytes) { memset(ab, 0, sizeof(*ab)); /* Type 1/2 specific fields */ if ((ab_bytes[0] & 0x1f) == 0x1f) { ab->ab_type = 1; ab->u.type_1.crc = ab_bytes[0] >> 5 & 0x07; ab->u.type_1.burst_qual = ab_bytes[2]; ab->u.type_1.frame_qual = ab_bytes[3]; } else if ((ab_bytes[0] & 0x1f) == 0) { ab->ab_type = 2; ab->u.type_2.abi = ab_bytes[0] >> 5 & 0x07; ab->u.type_2.type = ab_bytes[3] >> 6 & 0x03; } else return -EINVAL; /* Common fields */ ab->rxlev = ab_bytes[1]; ab->acc_delay = (ab_bytes[4] << 2) & 0x0300; ab->acc_delay |= ab_bytes[5]; ab->data = (ab_bytes[6] << 3) & 0x0700; ab->data |= ab_bytes[7]; return 0; } static int enc_pcu_sync_ind_16(ubit_t *trau_bits, struct er_pcu_sync_ind *ind) { /* 16kbps PCU-SYNC-IND TRAU frame format: * Direction: PCU => CCU * * (bit 0) 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 1 C1 C2 C3 C4 C5 C6 C7 * C8 PC 0. 0 0 0 0 0 * 1 0 0 0 0 0 0 0 * 0 D15 D16 D17 D18 D19 D20 D21 PSEQ (offset 41) * 1 D22 D23 D24 D25 D26 D27 D28 * D29 D30 D31 D32 D33 D34 D35 D36 * 1 D37 D38 D39 D40 D41 D42 D43 SS (offset 65) * D44 D45 D46 D47 D48 D49 D50 D51 * 1 1 1 1 1 1 1 1 * 1 D60 D61 D62 D63 D64 D65 D66 FN UL (offset 89) * 1 D67 D68 D69 D70 D71 D72 D73 * D74 D75 D76 D77 D78 D79 D80 D81 * 1 D82 D83 D84 D85 D86 D87 D88 FN SS (offset 113) * D89 D90 D91 D92 D93 D94 D95 D96 * 1 1 1 1 1 1 1 1 * 1 D105 D106 D107 D108 D109 D110 D111 FN DL (offset 137) * 1 D112 D113 D114 D115 D116 D117 D118 * D119 D120 D121 D122 D123 D124 D125 D126 * 1 D127 D128 D129 D130 D131 D132 D133 LS (offset 161) * D134 D135 D136 D137 D138 D139 D140 D141 * 1 1 1 1 1 1 1 1 * 1 1 1 ... * ... 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 TA1 TA2 TA3 TA4 (bit 319) * TA5* TA6* TA7* TA8* * * "*" = additional TA bits to delay the frame * C = Control bits * D = Data bits * PC = Parity over C-Bits (odd) */ pbit_t c_1_5 = PCU_TRAU_ER_FT_PCU_SYNC_IND; int rc; /* C-Bits */ osmo_pbit2ubit_ext(trau_bits, 17, &c_1_5, 0, 5, 1); osmo_pbit2ubit_ext(trau_bits, 22, (pbit_t *) &ind->tav, 0, 2, 1); if (ind->ul_frame_err) trau_bits[24] = 0; trau_bits[25] = calc_parity(trau_bits + 17, 8); /* D-Bits */ rc = put_trau_uint32(trau_bits, 320, T_bits_16, sizeof(T_bits_16), ind->pseq, 41, 22); if (rc < 0) return -EINVAL; rc = put_trau_uint32(trau_bits, 320, T_bits_16, sizeof(T_bits_16), ind->ss, 65, 15); if (rc < 0) return -EINVAL; rc = put_trau_uint32(trau_bits, 320, T_bits_16, sizeof(T_bits_16), ind->fn_ul, 89, 22); if (rc < 0) return -EINVAL; rc = put_trau_uint32(trau_bits, 320, T_bits_16, sizeof(T_bits_16), ind->fn_ss, 113, 15); if (rc < 0) return -EINVAL; rc = put_trau_uint32(trau_bits, 320, T_bits_16, sizeof(T_bits_16), ind->fn_dl, 137, 22); if (rc < 0) return -EINVAL; rc = put_trau_uint32(trau_bits, 320, T_bits_16, sizeof(T_bits_16), ind->ls, 161, 15); if (rc < 0) return -EINVAL; return set_timing_ajustment_bits_16(trau_bits, ind->tav); } int enc_pcu_data_ind_16(ubit_t *trau_bits, struct er_pcu_data_ind *ind) { /* 16kbps PCU-DATA-IND TRAU frame format: * Direction: PCU => CCU * * (bit 0) 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 1 C1 C2 C3 C4 C5 C6 C7 * C8 PC E1 E2 E3 E4 E5 E6 * E7 E8 E9 E10 E11 E12 E13 E14 * E15 E16 PE D1 D2 D3 D4 D5 * D6 D7 D8 D9 D10 D11 D12 D13 * D14 D15 D16 ... * ... D267 D268 D269 * D270 D271 D272 D273 TA1 TA2 TA3 TA4 (bit 319) * TA5* TA6* TA7* TA8* * * C = Control bits * D = Data bits * E = Extended control bits * PC = Parity over C-Bits (odd) * PE = Parity over extended control bits (odd) */ pbit_t c_1_5 = PCU_TRAU_ER_FT_DATA_IND; /* C-Bits */ osmo_pbit2ubit_ext(trau_bits, 17, &c_1_5, 0, 5, 1); osmo_pbit2ubit_ext(trau_bits, 22, (pbit_t *) &ind->tav, 0, 2, 1); if (ind->ul_frame_err) trau_bits[24] = 0; trau_bits[25] = calc_parity(trau_bits + 17, 8); /* Set coding scheme (E1-E2) */ switch (ind->cs_hdr) { case CS_OR_HDR_CS1: trau_bits[26] = 0; trau_bits[27] = 0; break; case CS_OR_HDR_CS2: trau_bits[26] = 0; trau_bits[27] = 1; break; default: /* NOTE: The 16K TRAU frames do not have enough bandwidth to * support coding schemes other than CS1 and CS2 */ /* NOTE: Access bursts (AB) are uplink-only. */ return -EINVAL; } /* Set demodulation in uplink (E3-E4) */ switch (ind->ul_chan_mode) { case ER_UL_CHMOD_NB_GMSK: case ER_UL_CHMOD_NB_UNKN: trau_bits[28] = 0; trau_bits[29] = 0; break; case ER_UL_CHMOD_AB: trau_bits[28] = 0; trau_bits[29] = 1; break; case ER_UL_CHMOD_AB_UNKN: trau_bits[28] = 1; trau_bits[29] = 0; break; case ER_UL_CHMOD_VOID: trau_bits[28] = 1; trau_bits[29] = 1; break; default: return -EINVAL; } /* Timing offset (E5-E12, 8 bit value, MSB first) */ osmo_pbit2ubit_ext(trau_bits, 30, (pbit_t *) &ind->timing_offset, 0, 8, 0); /* Power control (E13-E16, 4 bit value, MSB first, 2dB steps) */ osmo_pbit2ubit_ext(trau_bits, 38, (pbit_t *) &ind->atten_db, 4, 4, 0); /* Parity (odd) over coding scheme, demodulation, timing offset and * power control bits (E1-E16) */ trau_bits[42] = calc_parity(trau_bits + 26, 16); /* Data bits */ switch (ind->cs_hdr) { case CS_OR_HDR_CS1: osmo_pbit2ubit_ext(trau_bits, 43, (pbit_t *) ind->data, 0, 184, 1); osmo_crc16gen_set_bits(&cs1_crc16, trau_bits + 43, 184, trau_bits + 43 + 184); break; case CS_OR_HDR_CS2: osmo_pbit2ubit_ext(trau_bits, 43, (pbit_t *) ind->data, 0, 271, 1); break; default: /* NOTE: The 16K TRAU frames do not have enough bandwidth to * support coding schemes other than CS1 and CS2 */ return -EINVAL; } return set_timing_ajustment_bits_16(trau_bits, ind->tav); } /*! encode an 16k Ericsson GPRS (GSL) TRAU frame. * \param[out] bits caller-allocated memory for unpacked output bits (320+4). * \param[in] fr input data structure describing TRAU frame. * \return number of bits encoded. */ int er_gprs_trau_frame_encode_16k(ubit_t *bits, struct er_gprs_trau_frame *fr) { /* Prepare frame: first 16 bits set 0, remaining bits set to 1 */ memset(bits, 0, 16); memset(bits + 16, 1, 320 + 4 - 16); switch (fr->type) { case ER_GPRS_TRAU_FT_SYNC: return enc_pcu_sync_ind_16(bits, &fr->u.pcu_sync_ind); case ER_GPRS_TRAU_FT_DATA: return enc_pcu_data_ind_16(bits, &fr->u.pcu_data_ind); default: return -EINVAL; } return -EINVAL; } static int dec_ccu_sync_ind_16(struct er_ccu_sync_ind *ind, const ubit_t *trau_bits) { /* 16kbps CCU-SYNC-IND TRAU frame format: * Direction: CCU => PCU * * (bit 0) 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 1 C1 C2 C3 C4 C5 C6 C7 * C8 PC E1 PE 1 1 1 1 * 1 0 0 0 0 0 0 0 * 0 D13 D14 D15 D16 D17 D18 D19 PSEQ (offset 41) * 1 D20 D21 D22 D23 D24 D25 D26 * D27 D28 D29 D30 D31 D32 D33 D34 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 D58 D59 D60 D61 D62 D63 D64 AFN UL (offset 89) * 1 D65 D66 D67 D68 D69 D70 D71 * D72 D73 D74 D75 D76 D77 D78 D79 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 D103 D104 D105 D106 D107 D108 D109 AFN DL (offset 137) * 1 D110 D111 D112 D113 D114 D115 D116 * D117 D118 D119 D120 D121 D122 D123 D124 * 1 1 1 1 1 1 1 1 * 1 1 1 ... * ... 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 TA1 TA2 (bit 319) * TA3* TA4* * * "*" = additional TA bits to delay the frame * C = Control bits * D = Data bits * E = Extended control bits * PC = Parity over C-Bits (odd) * PE = Parity over extended control bits (odd) */ size_t i; /* Validate sync pattern (extended) */ for (i = 0; i < 19; i++) { if (trau_bits[16 + i * 16] != 1) { LOGP(DLINP, LOGL_ERROR, "CCU-SYNC-IND-16: invalid sync pattern (T1 at position %zu != 1)\n", i); return -EINVAL; } } /* Validate C-Bits */ if (calc_parity(trau_bits + 17, 8) != trau_bits[25]) { LOGP(DLINP, LOGL_ERROR, "CCU-SYNC-IND-16: invalid parity (C1-C8)\n"); return -EINVAL; } /* TAV (C7-C9) */ osmo_ubit2pbit_ext((pbit_t *) &ind->tav, 0, trau_bits, 22, 2, 1); /* Downlink frame error, DFE (C8) */ if (trau_bits[24] == 0) ind->dfe = true; /* Check (odd) parity of E1 bit */ if (trau_bits[26] != ((~trau_bits[27]) & 1)) { LOGP(DLINP, LOGL_ERROR, "CCU-SYNC-IND-16: invalid parity (E1)\n"); return -EINVAL; } /* Downlink Block error, DBE (E1) */ if (trau_bits[26] == 0) ind->dbe = true; /* D bits */ ind->pseq = get_trau_uint32(trau_bits, 320, T_bits_16, sizeof(T_bits_16), 41, 22); ind->afn_ul = get_trau_uint32(trau_bits, 320, T_bits_16, sizeof(T_bits_16), 89, 22); ind->afn_dl = get_trau_uint32(trau_bits, 320, T_bits_16, sizeof(T_bits_16), 137, 22); return 0; } static int dec_ccu_data_ind_16(struct er_ccu_data_ind *ind, const ubit_t *trau_bits) { /* 16kbps CCU-DATA-IND TRAU frame format: * Direction: CCU => PCU * * (bit 0) 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 1 C1 C2 C3 C4 C5 C6 C7 * PC E1 E2 E3 E4 E5 E6 E7 * E8 E9 E10 E11 E12 E13 E14 E15 * E16 E17 E18 E19 PE D1 D2 D3 * D4 D5 D6 D7 D8 D9 D10 D11 * D12 D13 D14 ... * ... D267 D268 D269 * D270 D271 D272 D273 TA1 TA2 TA3 TA4 (bit 319) * TA5* TA6* TA7* TA8* * * C = Control bits * D = Data bits * E = Extended control bits * PC = Parity over C-Bits (odd) * PE = Parity over extended control bits (odd) */ uint8_t sfq = 0; uint8_t eadd = 0; uint8_t e_2_4 = 0; int rc; int i; /* Validate C-Bits */ if (calc_parity(trau_bits + 17, 7) != trau_bits[24]) { LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-16: invalid parity (C1-C7)\n"); return -EINVAL; } /* TAV (C6-C7) */ osmo_ubit2pbit_ext((pbit_t *) &ind->tav, 0, trau_bits, 22, 2, 1); /* Validate E-Bits */ if (calc_parity(trau_bits + 25, 19) != trau_bits[44]) { LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-16: invalid parity (E1-E19)\n"); return -EINVAL; } /* Downlink block error (E1) */ if (trau_bits[25] == 0) ind->dbe = true; /* Coding scheme (E2-E4) */ osmo_ubit2pbit_ext((pbit_t *) &e_2_4, 5, trau_bits, 26, 3, 0); switch (e_2_4) { case 0: ind->cs_hdr = CS_OR_HDR_CS1; break; case 1: ind->cs_hdr = CS_OR_HDR_CS2; break; case 4: ind->cs_hdr = CS_OR_HDR_AB; break; default: /* 16kbps timeslots only support CS1, CS2 and AB are supported, * due to bandwidth limitations. */ LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-16: invalid codec status (E2-E4)\n"); return -EINVAL; } /* Soft frame quality SFQ (E5-E7, 0 in case of AB) */ osmo_ubit2pbit_ext((pbit_t *) &sfq, 5, trau_bits, 29, 3, 0); ind->u.gprs.block_qual = sfq; /* Parity Check (E8, 1 in case of AB) */ ind->u.gprs.parity_ok = trau_bits[32]; /* RX-LEV (E9-E14, 63 in case of AB) */ osmo_ubit2pbit_ext((pbit_t *) &ind->rx_lev, 2, trau_bits, 33, 6, 0); /* Estimated access delay (E15-E17, 0 in case of AB) */ osmo_ubit2pbit_ext((pbit_t *) &eadd, 5, trau_bits, 39, 3, 0); switch (eadd) { case 0: /* <2 or less */ ind->est_acc_del_dev = -3; break; case 1: ind->est_acc_del_dev = -1; break; case 2: ind->est_acc_del_dev = 1; break; case 4: ind->est_acc_del_dev = 2; break; case 5: /* >2 or more */ ind->est_acc_del_dev = 3; break; case 6: ind->est_acc_del_dev = 0; break; case 7: ind->est_acc_del_dev = -2; break; default: LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-16: invalid estimated access delay (E15-E17)\n"); return -EINVAL; } /* Data bits */ switch (ind->cs_hdr) { case CS_OR_HDR_CS1: osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 45, 184, 1); rc = osmo_crc16gen_check_bits(&cs1_crc16, trau_bits + 45, 184, trau_bits + 45 + 184); if (rc != 0) { LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-16: CRC error in CS1 block\n"); return -EINVAL; } ind->data_len = 23; break; case CS_OR_HDR_CS2: osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 45, 271, 1); ind->data_len = 34; break; case CS_OR_HDR_AB: /* Note: The useful data starts at D4 and is byte-aligned inside the TRAU frame. * The data string contains 4 items, each 8 bytes long, 32 bytes total. */ osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 48, 256, 1); ind->data_len = 32; for (i = 0; i < 4; i++) { rc = decode_ab(&ind->ab[i], ind->data + i * 8); if (rc < 0) return -EINVAL; } break; default: LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-16: invalid cs_hdr set\n"); return -EINVAL; } return 0; }; /*! decode an 16k Ericsson GPRS (GSL) TRAU frame. * \param[out] fr caller-allocated output data structure. * \param[in] bits unpacked input bits (320). * \return 0 on success; negative in case of error. */ int er_gprs_trau_frame_decode_16k(struct er_gprs_trau_frame *fr, const ubit_t *bits) { uint8_t c_1_5 = 0; const ubit_t expected_sync_pattern[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 }; int rc; memset(fr, 0, sizeof(*fr)); /* Validate sync pattern */ if (memcmp(bits, expected_sync_pattern, ARRAY_SIZE(expected_sync_pattern)) != 0) { LOGP(DLINP, LOGL_ERROR, "CCU-XXXX-IND-16: invalid sync pattern (T0)\n"); return -EINVAL; } /* Determine frame type */ osmo_ubit2pbit_ext((pbit_t *) &c_1_5, 0, bits, 17, 5, 1); switch (c_1_5) { case PCU_TRAU_ER_FT_CCU_SYNC_IND: fr->type = ER_GPRS_TRAU_FT_SYNC; rc = dec_ccu_sync_ind_16(&fr->u.ccu_sync_ind, bits); break; case PCU_TRAU_ER_FT_DATA_IND: fr->type = ER_GPRS_TRAU_FT_DATA; rc = dec_ccu_data_ind_16(&fr->u.ccu_data_ind, bits); break; default: LOGP(DLINP, LOGL_ERROR, "CCU-XXXX-IND-16: invalid frame type (%02x)\n", c_1_5); rc = -EINVAL; } /* Ensure that we exit with predictable data in case of error. */ if (rc < 0) memset(fr, 0, sizeof(*fr)); return rc; } /* Extract the CPS field from a given block, block must have minimum length of 5 bytes. * See also: 3GPP TS 44.060, section 10.3a.3 and section 10.3a.4 */ static int cps_from_mcs_block(uint8_t *block, enum er_cs_or_hdr cs_hdr, bool uplink) { uint8_t cps; if (uplink) { switch (cs_hdr) { case CS_OR_HDR_HDR1: cps = block[4] & 0x1f; break; case CS_OR_HDR_HDR2: cps = (block[2] >> 6) & 0x3; cps |= block[3] << 2 & 0x4; break; case CS_OR_HDR_HDR3: cps = (block[2] >> 6) & 0x3; cps |= block[3] << 2 & 0xC; break; default: return -EINVAL; } } else { switch (cs_hdr) { case CS_OR_HDR_HDR1: cps = (block[4] >> 3) & 0x1f; break; case CS_OR_HDR_HDR2: cps = (block[3] >> 1) & 0x07; break; case CS_OR_HDR_HDR3: cps = (block[3] >> 1) & 0x0f; break; default: return -EINVAL; } } return cps; } /* Determine the MCS block type from a given CPS value. * See also: 3GPP TS 44.060, section 10.4.8a */ static int mcs_from_cps(uint8_t cps, enum er_cs_or_hdr cs_hdr) { switch (cs_hdr) { case CS_OR_HDR_HDR1: if (cps <= 0x0A) return 9; if (cps <= 0x13) return 8; if (cps <= 0x1C) return 7; return -EINVAL; break; case CS_OR_HDR_HDR2: if (cps <= 0x03 || cps == 0x06 || cps == 0x07) return 6; if (cps == 4 || cps == 5) return 5; return -EINVAL; break; case CS_OR_HDR_HDR3: if (cps <= 0x02) return 4; if (cps <= 0x08) return 3; if (cps == 0x09 || cps == 0x0A || cps == 0x0D || cps == 0x0E) return 2; if (cps == 0x0B || cps == 0x0C) return 1; return -EINVAL; break; default: return -EINVAL; } } static int enc_pcu_sync_ind_64(ubit_t *trau_bits, struct er_pcu_sync_ind *ind) { /* 64kbps PCU-SYNC-IND TRAU frame format: * Direction: PCU => CCU * * (bit 0) 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 1 C1 C2 C3 C4 C5 C6 C7 * C8 PC 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 D96 D97 D98 D99 D100 D101 * D102 D103 D104 D105 D106 D107 D108 D109 * D110 D111 D112 D113 D114 D115 D116 D117 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * D133 D134 D135 D136 D137 D138 D139 D140 * D141 D142 D143 D144 D145 D146 D147 D148 * 1 1 1 1 1 1 1 1 * 1 1 D159 D160 D161 D162 D163 D164 * D165 D166 D167 D168 D169 D170 D171 D172 * D173 D174 D175 D176 D177 D178 D179 D180 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * D196 D197 D198 D199 D200 D201 D202 D203 * D204 D205 D206 D207 D208 D209 D210 D211 * 1 1 1 1 1 1 1 1 * 1 1 D222 D223 D224 D225 D226 D227 * D228 D229 D230 D231 D232 D233 D234 D235 * D236 D237 D238 D239 D340 D241 D242 D243 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * D259 D260 D261 D262 D263 D264 D265 D266 * D267 D268 D269 D270 D271 D272 D273 D274 * 1 1 1 1 1 1 1 1 * 1 1 1 ... * ... 1 1 1 * 1 1 1 1 1 1 1 1 * TA1 TA2 TA3 TA4 TA5 TA6 TA7 TA8 * TA9 TA10 TA11 TA12 TA13 TA14 TA15 TA16 (bit 1279) * TA17* TA18* TA19* TA20* TA21* TA22* TA23* TA24* * TA25* TA26* TA27* TA28* TA29* TA30* TA31* TA32* * * "*" = additional TA bits to delay the frame * C = Control bits * D = Data bits * E = Extended control bits * PC = Parity over C-Bits (odd) * PE = Parity over extended control bits (odd) */ pbit_t c_1_5 = PCU_TRAU_ER_FT_PCU_SYNC_IND; int rc; /* C-Bits */ osmo_pbit2ubit_ext(trau_bits, 65, &c_1_5, 0, 5, 1); osmo_pbit2ubit_ext(trau_bits, 70, (pbit_t *) &ind->tav, 0, 2, 1); if (ind->ul_frame_err) trau_bits[73] = 0; trau_bits[74] = calc_parity(trau_bits + 65, 8); /* unused D-bits are initialized in er_gprs_trau_frame_encode */ /* D-Bits */ rc = put_trau_uint32(trau_bits, 1280, T_bits_64, sizeof(T_bits_64), ind->pseq, 170, 22); if (rc < 0) return -EINVAL; rc = put_trau_uint32(trau_bits, 1280, T_bits_64, sizeof(T_bits_64), ind->ss, 208, 16); if (rc < 0) return -EINVAL; rc = put_trau_uint32(trau_bits, 1280, T_bits_64, sizeof(T_bits_64), ind->fn_ul, 234, 22); if (rc < 0) return -EINVAL; rc = put_trau_uint32(trau_bits, 1280, T_bits_64, sizeof(T_bits_64), ind->fn_ss, 272, 15); if (rc < 0) return -EINVAL; rc = put_trau_uint32(trau_bits, 1280, T_bits_64, sizeof(T_bits_64), ind->fn_dl, 298, 22); if (rc < 0) return -EINVAL; rc = put_trau_uint32(trau_bits, 1280, T_bits_64, sizeof(T_bits_64), ind->ls, 336, 16); if (rc < 0) return -EINVAL; return set_timing_ajustment_bits_64(trau_bits, ind->tav); } int enc_pcu_data_ind_64(ubit_t *trau_bits, struct er_pcu_data_ind *ind, uint8_t mcs) { /* 64kbps PCU-DATA-IND TRAU frame format: * Direction: PCU => CCU * * (bit 0) 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 1 C1 C2 C3 C4 C5 C6 C7 * C8 PC E1 E2 E3 E4 E5 E6 * E7 E8 E9 E10 E11 E12 E13 E14 * E15 E16 E17 E18 E19 E20 E21 E22 * E23 E24 E25 E26 E27 E28 E29 E30 * E31 E32 E33 E34 E35 E36 PE S1 * S2 S3 S4 S5 S6 S7 S8 S9 * S10 S11 S12 S13 S14 S15 S16 S17 * S18 S19 S20 S21 D1 D2 D3 D4 * D5 D6 D7 D8 D9 D10 D11 D12 * D13 D14 D15 D16 D17 D18 D19 D20 * D21 D22 D23 ... * ... D1130 D1131 D1132 * TA1 TA2 TA3 TA4 TA5 TA6 TA7 TA8 * TA9 TA10 TA11 TA12 TA13 TA14 TA15 TA16 (bit 1279) * TA17* TA18* TA19* TA20* TA21* TA22* TA23* TA24* * TA25* TA26* TA27* TA28* TA29* TA30* TA31* TA32* * * C = Control bits * D = Data bits * E = Extended control bits * PC = Parity over C-Bits (odd) * PE = Parity over extended control bits (odd) */ pbit_t c_1_5 = PCU_TRAU_ER_FT_DATA_IND; /* C-Bits */ osmo_pbit2ubit_ext(trau_bits, 65, &c_1_5, 0, 5, 1); osmo_pbit2ubit_ext(trau_bits, 70, (pbit_t *) &ind->tav, 0, 2, 1); if (ind->ul_frame_err) trau_bits[73] = 0; trau_bits[74] = calc_parity(trau_bits + 65, 8); /* Set coding scheme (E1-E3) */ switch (ind->cs_hdr) { case CS_OR_HDR_CS1: trau_bits[74] = 0; trau_bits[75] = 0; trau_bits[76] = 1; break; case CS_OR_HDR_CS2: trau_bits[74] = 0; trau_bits[75] = 1; trau_bits[76] = 0; break; case CS_OR_HDR_CS3: trau_bits[74] = 0; trau_bits[75] = 1; trau_bits[76] = 1; break; case CS_OR_HDR_CS4: trau_bits[74] = 1; trau_bits[75] = 0; trau_bits[76] = 0; break; case CS_OR_HDR_HDR1: trau_bits[74] = 1; trau_bits[75] = 0; trau_bits[76] = 1; break; case CS_OR_HDR_HDR2: trau_bits[74] = 1; trau_bits[75] = 1; trau_bits[76] = 0; break; case CS_OR_HDR_HDR3: trau_bits[74] = 1; trau_bits[75] = 1; trau_bits[76] = 1; break; default: /* NOTE: Access bursts (AB) are uplink-only. */ return -EINVAL; } /* Set demodulation in uplink (E4-E6) */ switch (ind->ul_chan_mode) { case ER_UL_CHMOD_VOID: trau_bits[77] = 0; trau_bits[78] = 0; trau_bits[79] = 0; break; case ER_UL_CHMOD_NB_GMSK: trau_bits[77] = 0; trau_bits[78] = 0; trau_bits[79] = 1; break; case ER_UL_CHMOD_NB_UNKN: trau_bits[77] = 0; trau_bits[78] = 1; trau_bits[79] = 0; break; case ER_UL_CHMOD_AB: trau_bits[77] = 0; trau_bits[78] = 1; trau_bits[79] = 1; break; case ER_UL_CHMOD_AB_UNKN: trau_bits[77] = 1; trau_bits[78] = 0; trau_bits[79] = 0; break; default: return -EINVAL; } /* Timing offset (E7-E14, 8 bit value, MSB first) */ osmo_pbit2ubit_ext(trau_bits, 80, (pbit_t *) &ind->timing_offset, 0, 8, 0); /* Power control (E33-E36, 4 bit value, MSB first, 2dB steps) */ osmo_pbit2ubit_ext(trau_bits, 106, (pbit_t *) &ind->atten_db, 4, 4, 0); /* Parity (odd) over coding scheme, demodulation, timing offset and * power control bits (E1-E36) */ trau_bits[110] = calc_parity(trau_bits + 74, 36); /* Data bits */ switch (ind->cs_hdr) { case CS_OR_HDR_CS1: osmo_pbit2ubit_ext(trau_bits, 132, (pbit_t *) ind->data, 0, 184, 1); osmo_crc16gen_set_bits(&cs1_crc16, trau_bits + 132, 184, trau_bits + 132 + 184); break; case CS_OR_HDR_CS2: osmo_pbit2ubit_ext(trau_bits, 132, (pbit_t *) ind->data, 0, 271, 1); break; case CS_OR_HDR_CS3: osmo_pbit2ubit_ext(trau_bits, 132, (pbit_t *) ind->data, 0, 315, 1); break; case CS_OR_HDR_CS4: osmo_pbit2ubit_ext(trau_bits, 132, (pbit_t *) ind->data, 0, 431, 1); break; case CS_OR_HDR_HDR1: case CS_OR_HDR_HDR2: case CS_OR_HDR_HDR3: switch (mcs) { case 1: osmo_pbit2ubit_ext(trau_bits, 132, (pbit_t *) ind->data, 0, 209, 1); break; case 2: osmo_pbit2ubit_ext(trau_bits, 132, (pbit_t *) ind->data, 0, 257, 1); break; case 3: osmo_pbit2ubit_ext(trau_bits, 132, (pbit_t *) ind->data, 0, 329, 1); break; case 4: osmo_pbit2ubit_ext(trau_bits, 132, (pbit_t *) ind->data, 0, 385, 1); break; case 5: osmo_pbit2ubit_ext(trau_bits, 132, (pbit_t *) ind->data, 0, 478, 1); break; case 6: osmo_pbit2ubit_ext(trau_bits, 132, (pbit_t *) ind->data, 0, 622, 1); break; case 7: osmo_pbit2ubit_ext(trau_bits, 132, (pbit_t *) ind->data, 0, 940, 1); break; case 8: osmo_pbit2ubit_ext(trau_bits, 132, (pbit_t *) ind->data, 0, 1132, 1); break; } break; default: /* NOTE: The 16K TRAU frames do not have enough bandwidth to * support coding schemes other than CS1 and CS2 */ return -EINVAL; } return set_timing_ajustment_bits_64(trau_bits, ind->tav); } int enc_pcu_data_ind_64_mcs9(ubit_t *trau_bits, struct er_pcu_data_ind *ind) { /* 64kbps PCU-DATA-IND (MCS9) TRAU frame format: * Direction: PCU => CCU * * (bit 0) 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 1 D1 D2 D3 D4 D5 D6 D7 * D8 D9 D10 D11 D12 D13 D14 D15 * D16 D17 D18 D19 D20 D21 D22 D23 * D24 D25 D26 D27 D28 D29 D30 D31 * D32 D33 D34 D35 D36 D37 D38 D39 * D40 D41 D42 D43 D44 D45 D46 D47 * D48 C1 C2 C3 C4 C5 C6 C7 * C8 PC E1 E2 E3 E4 E5 E6 * E7 E8 E9 PE D49 D50 D51 D52 * D53 D54 D55 D56 D57 D58 D59 D60 * D61 D62 D63 D64 D65 D66 D67 D68 * D69 D70 D71 ... * ... D1226 D1227 D1228 * TA1 TA2 TA3 TA4 TA5 TA6 TA7 TA8 * TA9 TA10 TA11 TA12 TA13 TA14 TA15 TA16 (bit 1279) * TA17* TA18* TA19* TA20* TA21* TA22* TA23* TA24* * TA25* TA26* TA27* TA28* TA29* TA30* TA31* TA32* * * C = Control bits * D = Data bits * E = Extended control bits * PC = Parity over C-Bits (odd) * PE = Parity over extended control bits (odd) */ pbit_t c_1_5 = PCU_TRAU_ER_FT_DATA9_IND; /* NOTE: The ericsson MCS9 64K TRAU format uses a different sync * pattern than the other 64K TRAU frame formats. To make room for * the additional bits in MCS9 only the first 16 bits are T0 bits. */ trau_bits[16] = 1; /* Fill headroom that normally would have T0 and T1 bits with data * bits */ osmo_pbit2ubit_ext(trau_bits, 17, (pbit_t *) ind->data, 0, 48, 1); /* C-Bits */ osmo_pbit2ubit_ext(trau_bits, 65, &c_1_5, 0, 5, 1); osmo_pbit2ubit_ext(trau_bits, 70, (pbit_t *) &ind->tav, 0, 2, 1); if (ind->ul_frame_err) trau_bits[73] = 0; trau_bits[74] = calc_parity(trau_bits + 65, 8); /* Set demodulation in uplink (E1-E3) */ switch (ind->ul_chan_mode) { case ER_UL_CHMOD_VOID: trau_bits[74] = 0; trau_bits[75] = 0; trau_bits[76] = 0; break; case ER_UL_CHMOD_NB_GMSK: trau_bits[74] = 0; trau_bits[75] = 0; trau_bits[76] = 1; break; case ER_UL_CHMOD_NB_UNKN: trau_bits[74] = 0; trau_bits[75] = 1; trau_bits[76] = 0; break; case ER_UL_CHMOD_AB: trau_bits[74] = 0; trau_bits[75] = 1; trau_bits[76] = 1; break; case ER_UL_CHMOD_AB_UNKN: trau_bits[74] = 1; trau_bits[75] = 0; trau_bits[76] = 0; break; default: return -EINVAL; } /* E4-E5 are spare bits? */ /* Power control (E6-E9, 4 bit value, MSB first, 2dB steps) */ osmo_pbit2ubit_ext(trau_bits, 79, (pbit_t *) &ind->atten_db, 4, 4, 0); /* Parity (odd) over coding scheme, demodulation, timing offset and * power control bits (E1-E9) */ trau_bits[83] = calc_parity(trau_bits + 74, 9); /* Fill the rest of the block with data bits */ osmo_pbit2ubit_ext(trau_bits, 84, (pbit_t *) ind->data + 6, 0, 1180, 1); return set_timing_ajustment_bits_64(trau_bits, ind->tav); } /*! encode an 64k Ericsson GPRS (GSL) TRAU frame. * \param[out] bits caller-allocated memory for unpacked output bits (1280+16). * \param[in] fr input data structure describing TRAU frame. * \return number of bits encoded. */ int er_gprs_trau_frame_encode_64k(ubit_t *bits, struct er_gprs_trau_frame *fr) { int cps; int mcs = 0; enum er_cs_or_hdr cs; /* Prepare frame: first 16 bits set 0, remaining bits set to 1 */ memset(bits, 0, 64); memset(bits + 64, 1, 1280 + 16 - 64); switch (fr->type) { case ER_GPRS_TRAU_FT_SYNC: return enc_pcu_sync_ind_64(bits, &fr->u.pcu_sync_ind); case ER_GPRS_TRAU_FT_DATA: cs = fr->u.pcu_data_ind.cs_hdr; if (cs == CS_OR_HDR_HDR1 || cs == CS_OR_HDR_HDR2 || cs == CS_OR_HDR_HDR3) { cps = cps_from_mcs_block(fr->u.pcu_data_ind.data, cs, false); if (cps < 0) return -EINVAL; mcs = mcs_from_cps((uint8_t) cps, cs); if (mcs < 0) return -EINVAL; } if (mcs < 9) return enc_pcu_data_ind_64(bits, &fr->u.pcu_data_ind, mcs); else return enc_pcu_data_ind_64_mcs9(bits, &fr->u.pcu_data_ind); default: return -EINVAL; } return -EINVAL; } static int dec_ccu_sync_ind_64(struct er_ccu_sync_ind *ind, const ubit_t *trau_bits) { /* 64kbps CCU-SYNC-IND TRAU frame format: * Direction: CCU => PCU * * (bit 0) 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 1 C1 C2 C3 C4 C5 C6 C7 * C8 PC E1 PE 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 D94 D95 D96 D97 D98 D99 * D100 D101 D102 D103 D104 D105 D106 D107 * D108 D109 D110 D111 D112 D113 D114 D115 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 D157 D158 D159 D160 D161 D162 * D163 D164 D165 D166 D167 D168 D169 D170 * D171 D172 D173 D174 D175 D176 D177 D178 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 1 1 1 1 1 1 * 1 1 D220 D221 D222 D223 D224 D225 * D226 D227 D228 D229 D230 D231 D232 D233 * D234 D235 D236 D237 D238 D239 D240 D241 * 1 1 1 1 1 1 1 1 * 1 1 1 ... * ... 1 1 1 * 1 1 1 1 1 1 1 1 * TA1 TA2 TA3 TA4 TA5 TA6 TA7 TA8 * TA9 TA10 TA11 TA12 TA13 TA14 TA15 TA16 (bit 1279) * TA17* TA18* TA19* TA20* TA21* TA22* TA23* TA24* * TA25* TA26* TA27* TA28* TA29* TA30* TA31* TA32* * * "*" = additional TA bits to delay the frame * C = Control bits * D = Data bits * E = Extended control bits * PC = Parity over C-Bits (odd) * PE = Parity over extended control bits (odd) */ size_t i; /* Validate sync pattern (extended) */ for (i = 0; i < 19; i++) { if (trau_bits[64 + i * 64] != 1) { LOGP(DLINP, LOGL_ERROR, "CCU-SYNC-IND-64: invalid sync pattern (T1 at position %zu != 1)\n", i); return -EINVAL; } } /* Validate C-Bits */ if (calc_parity(trau_bits + 65, 8) != trau_bits[73]) { LOGP(DLINP, LOGL_ERROR, "CCU-SYNC-IND-64: invalid parity (C1-C8)\n"); return -EINVAL; } /* TAV (C6-C7) */ osmo_ubit2pbit_ext((pbit_t *) &ind->tav, 0, trau_bits, 70, 2, 1); /* Downlink frame error, DFE (C8) */ if (trau_bits[72] == 0) ind->dfe = true; /* Check (odd) parity of E1 bit */ if (trau_bits[74] != ((~trau_bits[75]) & 1)) { LOGP(DLINP, LOGL_ERROR, "CCU-SYNC-IND-64: invalid parity (E1)\n"); return -EINVAL; } /* Downlink Block error, DBE (E1) */ if (trau_bits[74] == 0) ind->dbe = true; /* D bits */ ind->pseq = get_trau_uint32(trau_bits, 1280, T_bits_64, sizeof(T_bits_64), 170, 22); ind->afn_ul = get_trau_uint32(trau_bits, 1280, T_bits_64, sizeof(T_bits_64), 234, 22); ind->afn_dl = get_trau_uint32(trau_bits, 1280, T_bits_64, sizeof(T_bits_64), 298, 22); return 0; } static int dec_ccu_data_ind_64(struct er_ccu_data_ind *ind, const ubit_t *trau_bits) { /* 64kbps CCU-DATA-IND TRAU frame format: * Direction: CCU => PCU * * (bit 0) 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 1 C1 C2 C3 C4 C5 C6 C7 * PC E1 E2 E3 E4 E5 E6 E7 * E8 E9 E10 E11 E12 E13 E14 E15 * E16 E17 E18 E19 E20 E21 E22 E23 * E24 E25 E26 E27 E28 E29 E30 E31 * E32 E33 E34 E35 E36 E37 E38 E39 * E40 E41 E42 E43 E44 E45 E46 E47 * E48 E49 E50 E51 E52 E53 E54 E55 * E56 E57 PE S1 S2 S3 D1 D2 * D3 D4 D5 D6 D7 D8 D9 D10 * D11 D12 D13 D14 D15 D16 D17 D18 * D19 D20 D21 ... * ... D1136 D1137 D1138 * TA1 TA2 TA3 TA4 TA5 TA6 TA7 TA8 * TA9 TA10 TA11 TA12 TA13 TA14 TA15 TA16 (bit 1279) * TA17* TA18* TA19* TA20* TA21* TA22* TA23* TA24* * TA25* TA26* TA27* TA28* TA29* TA30* TA31* TA32* * * C = Control bits * D = Data bits * E = Extended control bits * PC = Parity over C-Bits (odd) * PE = Parity over extended control bits (odd) */ uint8_t sfq = 0; uint8_t eadd = 0; uint8_t e_2_4 = 0; uint8_t mean_bep = 0; uint8_t cv_bep = 0; int cps; int mcs = 0; int rc; int i; /* Validate C-Bits */ if (calc_parity(trau_bits + 65, 7) != trau_bits[72]) { LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-64: invalid parity (C1-C7)\n"); return -EINVAL; } /* TAV (C6-C7) */ osmo_ubit2pbit_ext((pbit_t *) &ind->tav, 0, trau_bits, 70, 2, 1); /* Validate E-Bits */ if (calc_parity(trau_bits + 73, 57) != trau_bits[130]) { LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-64: invalid parity (E1-E57)\n"); return -EINVAL; } /* Downlink block error (E1) */ if (trau_bits[73] == 0) ind->dbe = true; /* Coding scheme (E2-E4) */ osmo_ubit2pbit_ext((pbit_t *) &e_2_4, 5, trau_bits, 74, 3, 0); switch (e_2_4) { case 0: ind->cs_hdr = CS_OR_HDR_AB; break; case 1: ind->cs_hdr = CS_OR_HDR_CS1; break; case 2: ind->cs_hdr = CS_OR_HDR_CS2; break; case 3: ind->cs_hdr = CS_OR_HDR_CS3; break; case 4: ind->cs_hdr = CS_OR_HDR_CS4; break; case 5: ind->cs_hdr = CS_OR_HDR_HDR1; break; case 6: ind->cs_hdr = CS_OR_HDR_HDR2; break; case 7: ind->cs_hdr = CS_OR_HDR_HDR3; break; default: LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-64: invalid codec status (E2-E4)\n"); return -EINVAL; } /* RX-LEV (E5-E10, 63 in case of AB) */ osmo_ubit2pbit_ext((pbit_t *) &ind->rx_lev, 2, trau_bits, 77, 6, 0); /* Estimated access delay (E11-E13, 0 in case of AB) */ osmo_ubit2pbit_ext((pbit_t *) &eadd, 5, trau_bits, 83, 3, 0); switch (eadd) { case 0: /* <2 or less */ ind->est_acc_del_dev = -3; break; case 1: ind->est_acc_del_dev = -1; break; case 2: ind->est_acc_del_dev = 1; break; case 4: ind->est_acc_del_dev = 2; break; case 5: /* >2 or more */ ind->est_acc_del_dev = 3; break; case 6: ind->est_acc_del_dev = 0; break; case 7: ind->est_acc_del_dev = -2; break; default: LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-64: invalid estimated access delay (E11-E13)\n"); return -EINVAL; } if (ind->cs_hdr == CS_OR_HDR_CS1 || ind->cs_hdr == CS_OR_HDR_CS2 || ind->cs_hdr == CS_OR_HDR_CS3 || ind->cs_hdr == CS_OR_HDR_CS4) { /* Soft frame quality SFQ (E14-E16, 0 in case of AB) */ osmo_ubit2pbit_ext((pbit_t *) &sfq, 5, trau_bits, 86, 3, 0); ind->u.gprs.block_qual = sfq; /* Parity Check (E17, 1 in case of AB) */ ind->u.gprs.parity_ok = trau_bits[89]; } else { /* Mean BEP (E14-E20) */ osmo_ubit2pbit_ext((pbit_t *) &mean_bep, 1, trau_bits, 86, 7, 0); ind->u.egprs.mean_bep = mean_bep; /* CV BEP (E21-E23) */ osmo_ubit2pbit_ext((pbit_t *) &cv_bep, 5, trau_bits, 93, 3, 0); ind->u.egprs.mean_bep = cv_bep; /* RLC/MAC header quality (E24) */ if (trau_bits[96] == 0) { ind->u.egprs.hdr_good = true; /* Data block quality (E25/E26) */ if (trau_bits[97] == 0) ind->u.egprs.data_good[0] = true; if (trau_bits[98] == 0) ind->u.egprs.data_good[1] = true; } else { ind->u.egprs.hdr_good = false; /* A bad RLC/MAC header always means that the the data blocks * cannot be valid. */ ind->u.egprs.data_good[0] = false; ind->u.egprs.data_good[1] = false; } } /* Data bits */ switch (ind->cs_hdr) { case CS_OR_HDR_CS1: osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 134, 184, 1); rc = osmo_crc16gen_check_bits(&cs1_crc16, trau_bits + 134, 184, trau_bits + 134 + 184); if (rc != 0) { LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-64: CRC error in CS1 block\n"); return -EINVAL; } ind->data_len = 23; break; case CS_OR_HDR_CS2: osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 134, 271, 1); ind->data_len = 34; break; case CS_OR_HDR_CS3: osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 134, 315, 1); ind->data_len = 40; break; case CS_OR_HDR_CS4: osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 134, 431, 1); ind->data_len = 54; break; case CS_OR_HDR_HDR1: case CS_OR_HDR_HDR2: case CS_OR_HDR_HDR3: osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 134, 40, 1); cps = cps_from_mcs_block(ind->data, ind->cs_hdr, true); if (cps < 0) { LOGP(DLINP, LOGL_DEBUG, "CCU-DATA-IND-64: unable to read CPS from data block, bad data block received?\n"); break; } mcs = mcs_from_cps((uint8_t) cps, ind->cs_hdr); if (mcs < 0) { LOGP(DLINP, LOGL_DEBUG, "CCU-DATA-IND-64: unable to determine coding scheme (MCS) from CPS, bad data block received?\n"); break; } /* Note: receiving noise (and eventually bad CPS field, may * happen from time to time and is not an error condition. */ switch (mcs) { case 1: osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 134, 209, 1); ind->data_len = 27; break; case 2: osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 134, 257, 1); ind->data_len = 33; break; case 3: osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 134, 329, 1); ind->data_len = 42; break; case 4: osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 134, 385, 1); ind->data_len = 49; break; case 5: osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 134, 487, 1); ind->data_len = 61; break; case 6: osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 134, 631, 1); ind->data_len = 79; break; case 7: osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 134, 946, 1); ind->data_len = 119; break; case 8: osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 134, 1138, 1); ind->data_len = 143; break; default: LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-64: invalid cs_hdr set\n"); return -EINVAL; } break; case CS_OR_HDR_AB: /* Note: The useful data starts at D13 and is byte-aligned inside the TRAU frame. * The data string contains 4 items, each 8 bytes long, 32 bytes total. */ osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, trau_bits, 144, 256, 1); ind->data_len = 32; for (i = 0; i < 4; i++) { rc = decode_ab(&ind->ab[i], ind->data + i * 8); if (rc < 0) return -EINVAL; } break; default: LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-64: invalid cs_hdr set\n"); return -EINVAL; } return 0; }; static int dec_ccu_data_ind_64_mcs9(struct er_ccu_data_ind *ind, const ubit_t *trau_bits) { /* 64kbps CCU-DATA-IND (MCS9) TRAU frame format: * Direction: CCU => PCU * * (bit 0) 0 0 0 0 0 0 0 0 * 0 0 0 0 0 0 0 0 * 1 D1 D2 D3 D4 D5 D6 D7 * D8 D9 D10 D11 D12 D13 D14 D15 * D16 D17 D18 D19 D20 D21 D22 D23 * D24 D25 D26 D27 D28 D29 D30 D31 * D32 D33 D34 D35 D36 D37 D38 D39 * D40 D41 D42 D43 D44 D45 D46 D47 * D48 C1 C2 C3 C4 C5 C6 C7 * PC E1 E2 E3 E4 E5 E6 E7 * E8 E9 E10 E11 E12 E13 E14 E15 * E16 E17 E18 E19 E20 E21 E22 E23 * PE S1 S2 D49 D50 D51 D52 D53 * D54 D55 D56 D57 D58 D59 D60 D61 * D62 D63 D64 ... * ... D1219 D1220 D1221 * TA1 TA2 TA3 TA4 TA5 TA6 TA7 TA8 * TA9 TA10 TA11 TA12 TA13 TA14 TA15 TA16 (bit 1279) * TA17* TA18* TA19* TA20* TA21* TA22* TA23* TA24* * TA25* TA26* TA27* TA28* TA29* TA30* TA31* TA32* * * C = Control bits * D = Data bits * E = Extended control bits * PC = Parity over C-Bits (odd) * PE = Parity over extended control bits (odd) */ ubit_t block[1234]; uint8_t eadd = 0; uint8_t mean_bep = 0; uint8_t cv_bep = 0; /* Validate C-Bits */ if (calc_parity(trau_bits + 65, 7) != trau_bits[72]) { LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-64: invalid parity (C1-C7)\n"); return -EINVAL; } /* TAV (C6-C7) */ osmo_ubit2pbit_ext((pbit_t *) &ind->tav, 0, trau_bits, 70, 2, 1); /* Validate E-Bits */ if (calc_parity(trau_bits + 73, 23) != trau_bits[96]) { LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-64: invalid parity (E1-E23)\n"); return -EINVAL; } /* Downlink block error (E1) */ if (trau_bits[73] == 0) ind->dbe = true; /* MCS9 uses CS header type 1 */ ind->cs_hdr = CS_OR_HDR_HDR1; /* RX-LEV (E2-E7) */ osmo_ubit2pbit_ext((pbit_t *) &ind->rx_lev, 2, trau_bits, 74, 6, 0); /* Estimated access delay (E8-E10) */ osmo_ubit2pbit_ext((pbit_t *) &eadd, 5, trau_bits, 80, 3, 0); switch (eadd) { case 0: /* <2 or less */ ind->est_acc_del_dev = -3; break; case 1: ind->est_acc_del_dev = -1; break; case 2: ind->est_acc_del_dev = 1; break; case 4: ind->est_acc_del_dev = 2; break; case 5: /* >2 or more */ ind->est_acc_del_dev = 3; break; case 6: ind->est_acc_del_dev = 0; break; case 7: ind->est_acc_del_dev = -2; break; default: LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-64: invalid estimated access delay (E8-E10)\n"); return -EINVAL; } /* Mean BEP (E11-E17) */ osmo_ubit2pbit_ext((pbit_t *) &mean_bep, 1, trau_bits, 83, 7, 0); ind->u.egprs.mean_bep = mean_bep; /* CV BEP (E18-E20) */ osmo_ubit2pbit_ext((pbit_t *) &cv_bep, 5, trau_bits, 90, 3, 0); ind->u.egprs.mean_bep = cv_bep; /* RLC/MAC header quality (E21) */ if (trau_bits[93] == 0) { ind->u.egprs.hdr_good = true; /* Data block quality (E22/E23) */ if (trau_bits[94] == 0) ind->u.egprs.data_good[0] = true; if (trau_bits[95] == 0) ind->u.egprs.data_good[1] = true; } else { /* A bad RLC/MAC header always means that the the data blocks * cannot be valid. */ ind->u.egprs.data_good[0] = false; ind->u.egprs.data_good[1] = false; } /* For capacity reasons the following fields are stripped from the * header: Spare, RSB, CPS. This means we have to restore those * fields to get a valid MCS9 block. See also: 3GPP TS 44.060, * section 10.3a.4.1 */ memcpy(block, trau_bits + 17, 32); block[32] = 0; /* CPS 0 */ block[33] = 0; /* CPS 1 */ block[34] = 0; /* CPS 2 */ block[35] = 0; /* CPS 3 */ block[36] = 0; /* CPS 4 */ block[37] = 0; /* RSB (not a resent block - guessed) */ block[38] = trau_bits[49]; /* PI */ block[39] = 0; /* Spare */ block[40] = 0; /* Spare */ block[41] = 0; /* Spare */ block[42] = 0; /* Spare */ block[43] = 0; /* Spare */ block[44] = 0; /* Spare */ block[45] = 0; /* Spare */ memcpy(block + 45, trau_bits + 50, 15); memcpy(block + 45, trau_bits + 99, 1173); osmo_ubit2pbit_ext((pbit_t *) &ind->data, 0, block, 0, sizeof(block), 1); return 0; } /*! decode an 64k Ericsson GPRS (GSL) TRAU frame. * \param[out] fr caller-allocated output data structure. * \param[in] bits unpacked input bits (1280). * \return 0 on success; negative in case of error. */ int er_gprs_trau_frame_decode_64k(struct er_gprs_trau_frame *fr, const ubit_t *bits) { uint8_t c_1_5 = 0; const ubit_t expected_sync_pattern[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, }; const ubit_t expected_sync_pattern_mcs9[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, }; int rc; memset(fr, 0, sizeof(*fr)); /* Determine frame type */ osmo_ubit2pbit_ext((pbit_t *) &c_1_5, 0, bits, 65, 5, 1); /* Validate sync patern */ switch (c_1_5) { case PCU_TRAU_ER_FT_CCU_SYNC_IND: case PCU_TRAU_ER_FT_DATA_IND: if (memcmp(bits, expected_sync_pattern, ARRAY_SIZE(expected_sync_pattern)) != 0) { LOGP(DLINP, LOGL_ERROR, "CCU-XXXX-IND-64: invalid sync pattern (T0,T1)\n"); return -EINVAL; } break; case PCU_TRAU_ER_FT_DATA9_IND: if (memcmp(bits, expected_sync_pattern_mcs9, ARRAY_SIZE(expected_sync_pattern_mcs9)) != 0) { LOGP(DLINP, LOGL_ERROR, "CCU-DATA-IND-64: invalid sync pattern (T0,T1)\n"); return -EINVAL; } break; default: LOGP(DLINP, LOGL_ERROR, "CCU-XXXX-IND-64: invalid frame type (%02x)\n", c_1_5); rc = -EINVAL; } /* Decode frame */ switch (c_1_5) { case PCU_TRAU_ER_FT_CCU_SYNC_IND: fr->type = ER_GPRS_TRAU_FT_SYNC; rc = dec_ccu_sync_ind_64(&fr->u.ccu_sync_ind, bits); break; case PCU_TRAU_ER_FT_DATA_IND: fr->type = ER_GPRS_TRAU_FT_DATA; rc = dec_ccu_data_ind_64(&fr->u.ccu_data_ind, bits); break; case PCU_TRAU_ER_FT_DATA9_IND: fr->type = ER_GPRS_TRAU_FT_DATA; rc = dec_ccu_data_ind_64_mcs9(&fr->u.ccu_data_ind, bits); break; default: LOGP(DLINP, LOGL_ERROR, "CCU-XXXX-IND-64: invalid frame type (%02x)\n", c_1_5); rc = -EINVAL; } /* Ensure that we exit with predictable data in case of error. */ if (rc < 0) memset(fr, 0, sizeof(*fr)); return rc; }