| /* GSM Radio Signalling Link messages on the A-bis interface |
| * 3GPP TS 08.58 version 8.6.0 Release 1999 / ETSI TS 100 596 V8.6.0 */ |
| |
| /* (C) 2008 by Harald Welte <laforge@gnumonks.org> |
| * All Rights Reserved |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| */ |
| |
| #include <stdio.h> |
| #include <errno.h> |
| #include <sys/types.h> |
| |
| #include "gsm_data.h" |
| #include "gsm_04_08.h" |
| #include "abis_rsl.h" |
| #include "debug.h" |
| #include "tlv.h" |
| |
| #define RSL_ALLOC_SIZE 1024 |
| |
| static u_int8_t mdisc_by_msgtype(u_int8_t msg_type) |
| { |
| /* mask off the transparent bit ? */ |
| msg_type &= 0xfe; |
| |
| if (msg_type & 0xf0 == 0x00) |
| return ABIS_RSL_MDISC_RLL; |
| if (msg_type & 0xf0 == 0x10) { |
| if (msg_type >= 0x19 && msg_type <= 0x22) |
| return ABIS_RSL_MDISC_TRX; |
| else |
| return ABIS_RSL_MDISC_COM_CHAN; |
| } |
| if (msg_type & 0xc == 0x00) |
| return ABIS_RSL_MDISC_DED_CHAN; |
| |
| return ABIS_RSL_MDISC_LOC; |
| } |
| |
| static inline void init_dchan_hdr(struct abis_rsl_dchan_hdr *dh, |
| u_int8_t msg_type) |
| { |
| dh->c.msg_discr = mdisc_by_msgtype(msg_type); |
| dh->c.msg_type = msg_type; |
| dh->ie_chan = RSL_IE_CHAN_NR; |
| } |
| |
| static inline void init_llm_hdr(struct abis_rsl_rll_hdr *dh, |
| u_int8_t msg_type) |
| { |
| /* dh->c.msg_discr = mdisc_by_msgtype(msg_type); */ |
| dh->c.msg_discr = ABIS_RSL_MDISC_RLL; |
| dh->c.msg_type = msg_type; |
| dh->ie_chan = RSL_IE_CHAN_NR; |
| dh->ie_link_id = RSL_IE_LINK_IDENT; |
| } |
| |
| |
| /* encode channel number as per Section 9.3.1 */ |
| u_int8_t rsl_enc_chan_nr(u_int8_t type, u_int8_t subch, u_int8_t timeslot) |
| { |
| u_int8_t ret; |
| |
| ret = (timeslot & 0x07) | type; |
| |
| switch (type) { |
| case RSL_CHAN_Lm_ACCHs: |
| subch &= 0x01; |
| break; |
| case RSL_CHAN_SDCCH4_ACCH: |
| subch &= 0x07; |
| break; |
| case RSL_CHAN_SDCCH8_ACCH: |
| subch &= 0x07; |
| break; |
| default: |
| /* no subchannels allowed */ |
| subch = 0x00; |
| break; |
| } |
| ret |= (subch << 3); |
| |
| return ret; |
| } |
| |
| /* As per TS 03.03 Section 2.2, the IMSI has 'not more than 15 digits' */ |
| u_int64_t str_to_imsi(const char *imsi_str) |
| { |
| u_int64_t ret; |
| |
| ret = strtoull(imsi_str, NULL, 10); |
| |
| return ret; |
| } |
| |
| /* Table 5 Clause 7 TS 05.02 */ |
| unsigned int n_pag_blocks(int bs_ccch_sdcch_comb, unsigned int bs_ag_blks_res) |
| { |
| if (!bs_ccch_sdcch_comb) |
| return 9 - bs_ag_blks_res; |
| else |
| return 3 - bs_ag_blks_res; |
| } |
| |
| /* Chapter 6.5.2 of TS 05.02 */ |
| unsigned int get_ccch_group(u_int64_t imsi, unsigned int bs_cc_chans, |
| unsigned int n_pag_blocks) |
| { |
| return (imsi % 1000) % (bs_cc_chans * n_pag_blocks) / n_pag_blocks; |
| } |
| |
| /* Chapter 6.5.2 of TS 05.02 */ |
| unsigned int get_paging_group(u_int64_t imsi, unsigned int bs_cc_chans, |
| int n_pag_blocks) |
| { |
| return (imsi % 1000) % (bs_cc_chans * n_pag_blocks) % n_pag_blocks; |
| } |
| |
| /* Send a BCCH_INFO message as per Chapter 8.5.1 */ |
| int rsl_bcch_info(struct gsm_bts *bts, u_int8_t type, |
| const u_int8_t *data, int len) |
| { |
| struct abis_rsl_dchan_hdr *dh; |
| struct msgb *msg = msgb_alloc(RSL_ALLOC_SIZE); |
| |
| dh = (struct abis_rsl_dchan_hdr *) msgb_put(msg, sizeof*dh); |
| init_dchan_hdr(dh, RSL_MT_BCCH_INFO); |
| dh->chan_nr = RSL_CHAN_BCCH; |
| |
| msgb_tv_put(msg, RSL_IE_SYSINFO_TYPE, type); |
| msgb_tlv_put(msg, RSL_IE_FULL_BCCH_INFO, len, data); |
| |
| return abis_rsl_sendmsg(bts, msg); |
| } |
| |
| int rsl_sacch_filling(struct gsm_bts *bts, u_int8_t type, |
| const u_int8_t *data, int len) |
| { |
| struct abis_rsl_common_hdr *ch; |
| struct msgb *msg = msgb_alloc(RSL_ALLOC_SIZE); |
| |
| ch = (struct abis_rsl_common_hdr *) msgb_put(msg, sizeof(*ch)); |
| ch->msg_discr = ABIS_RSL_MDISC_TRX; |
| ch->msg_type = RSL_MT_SACCH_FILL; |
| |
| msgb_tv_put(msg, RSL_IE_SYSINFO_TYPE, type); |
| msgb_tlv_put(msg, RSL_IE_L3_INFO, len, data); |
| |
| return abis_rsl_sendmsg(bts, msg); |
| } |
| |
| /* Chapter 8.4.1 */ |
| int rsl_chan_activate(struct gsm_bts *bts, u_int8_t chan_nr, |
| u_int8_t act_type, |
| struct rsl_ie_chan_mode *chan_mode, |
| struct rsl_ie_chan_ident *chan_ident, |
| u_int8_t bs_power, u_int8_t ms_power, |
| u_int8_t ta) |
| { |
| struct abis_rsl_dchan_hdr *dh; |
| struct msgb *msg = msgb_alloc(RSL_ALLOC_SIZE); |
| u_int8_t encr_info = 0x01; |
| |
| dh = (struct abis_rsl_dchan_hdr *) msgb_put(msg, sizeof(*dh)); |
| init_dchan_hdr(dh, RSL_MT_CHAN_ACTIV); |
| dh->chan_nr = chan_nr; |
| |
| msgb_tv_put(msg, RSL_IE_ACT_TYPE, act_type); |
| /* For compatibility with Phase 1 */ |
| msgb_tlv_put(msg, RSL_IE_CHAN_MODE, sizeof(*chan_mode), |
| (u_int8_t *) chan_mode); |
| msgb_tlv_put(msg, RSL_IE_CHAN_IDENT, 4, |
| (u_int8_t *) &chan_ident); |
| /* FIXME: this shoould be optional */ |
| msgb_tlv_put(msg, RSL_IE_ENCR_INFO, 1, |
| (u_int8_t *) &encr_info); |
| msgb_tv_put(msg, RSL_IE_BS_POWER, bs_power); |
| msgb_tv_put(msg, RSL_IE_MS_POWER, ms_power); |
| msgb_tv_put(msg, RSL_IE_TIMING_ADVANCE, ta); |
| |
| return abis_rsl_sendmsg(bts, msg); |
| } |
| |
| #define TSC 7 |
| |
| int rsl_chan_activate_tch_f(struct gsm_bts_trx_ts *ts) |
| { |
| u_int8_t chan_nr = rsl_enc_chan_nr(RSL_CHAN_Bm_ACCHs, 0, ts->nr); |
| u_int16_t arfcn = ts->trx->arfcn; |
| struct rsl_ie_chan_mode cm; |
| struct rsl_ie_chan_ident ci; |
| |
| cm.dtx_dtu = 0; |
| cm.spd_ind = RSL_CMOD_SPD_SPEECH; |
| cm.chan_rt = RSL_CMOD_CRT_TCH_Bm; |
| cm.chan_rate = RSL_CMOD_SP_GSM1; |
| |
| ci.chan_desc.iei = 0x64; |
| ci.chan_desc.chan_nr = chan_nr; |
| /* FIXME: this doesn't support hopping */ |
| ci.chan_desc.oct3 = (TSC << 5) | ((arfcn & 0x3ff) >> 8); |
| ci.chan_desc.oct4 = arfcn & 0xff; |
| #if 0 |
| ci.mobile_alloc.tag = 0x72; |
| ci.mobile_alloc.len = 0; /* as per Section 9.3.5 */ |
| #endif |
| |
| return rsl_chan_activate(ts->trx->bts, chan_nr, 0x01, &cm, &ci, 0x01, 0x0f, 0x00); |
| } |
| |
| int rsl_chan_activate_sdcch(struct gsm_bts_trx_ts *ts) |
| { |
| u_int8_t chan_nr = rsl_enc_chan_nr(RSL_CHAN_SDCCH4_ACCH, 0, ts->nr); |
| u_int16_t arfcn = ts->trx->arfcn; |
| struct rsl_ie_chan_mode cm; |
| struct rsl_ie_chan_ident ci; |
| |
| cm.dtx_dtu = 0x00; |
| cm.spd_ind = RSL_CMOD_SPD_SIGN; |
| cm.chan_rt = RSL_CMOD_CRT_SDCCH; |
| cm.chan_rate = 0x00; |
| |
| ci.chan_desc.iei = 0x64; |
| ci.chan_desc.chan_nr = chan_nr; |
| ci.chan_desc.oct3 = (TSC << 5) | ((arfcn & 0x3ff) >> 8); |
| ci.chan_desc.oct4 = arfcn & 0xff; |
| |
| /* FIXME: we're sending BS power IE, whcih Abissim doesn't */ |
| return rsl_chan_activate(ts->trx->bts, chan_nr, 0x00, &cm, &ci, 0x01, 0x0f, 0x00); |
| } |
| |
| int rsl_chan_release(struct gsm_bts_trx_ts *ts, u_int8_t chan_nr) |
| { |
| struct abis_rsl_dchan_hdr *dh; |
| struct msgb *msg = msgb_alloc(RSL_ALLOC_SIZE); |
| |
| dh = (struct abis_rsl_dchan_hdr *) msgb_put(msg, sizeof(*dh)); |
| init_dchan_hdr(dh, RSL_MT_RF_CHAN_REL); |
| dh->chan_nr = chan_nr; |
| |
| return abis_rsl_sendmsg(ts->trx->bts, msg); |
| } |
| |
| int rsl_paging_cmd(struct gsm_bts *bts, u_int8_t paging_group, u_int8_t len, |
| u_int8_t *ms_ident, u_int8_t chan_needed) |
| { |
| struct abis_rsl_dchan_hdr *dh; |
| struct msgb *msg = msgb_alloc(RSL_ALLOC_SIZE); |
| |
| dh = (struct abis_rsl_dchan_hdr *) msgb_put(msg, sizeof(*dh)); |
| init_dchan_hdr(dh, RSL_MT_PAGING_CMD); |
| dh->chan_nr = RSL_CHAN_PCH_AGCH; |
| |
| msgb_tv_put(msg, RSL_IE_PAGING_GROUP, paging_group); |
| msgb_tlv_put(msg, RSL_IE_MS_IDENTITY, len, ms_ident); |
| msgb_tv_put(msg, RSL_IE_CHAN_NEEDED, chan_needed); |
| |
| return abis_rsl_sendmsg(bts, msg); |
| } |
| |
| int imsi_str2bcd(u_int8_t *bcd_out, const char *str_in) |
| { |
| int i, len = strlen(str_in); |
| |
| for (i = 0; i < len; i++) { |
| int num = str_in[i] - 0x30; |
| if (num < 0 || num > 9) |
| return -1; |
| if (i % 2 == 0) |
| bcd_out[i/2] = num; |
| else |
| bcd_out[i/2] |= (num << 4); |
| } |
| |
| return 0; |
| } |
| |
| # if 0 |
| int rsl_paging_cmd_imsi(struct gsm_bts *bts, u_int8_t chan_needed, const char *imsi_str) |
| { |
| /* FIXME: derive the MS Identity */ |
| return rsl_paging_cmd(bts, paging_group, x, y, chan_needed); |
| } |
| #endif |
| |
| int rsl_imm_assign_cmd(struct gsm_bts *bts, u_int8_t len, u_int8_t *val) |
| { |
| struct msgb *msg = msgb_alloc(RSL_ALLOC_SIZE); |
| struct abis_rsl_dchan_hdr *dh; |
| |
| dh = (struct abis_rsl_dchan_hdr *) msgb_put(msg, sizeof(*dh)); |
| init_dchan_hdr(dh, RSL_MT_IMMEDIATE_ASSIGN_CMD); |
| dh->chan_nr = RSL_CHAN_PCH_AGCH; |
| |
| /* If phase 2, FULL_IMM_ASS_INFO */ |
| |
| msgb_tlv_put(msg, RSL_IE_IMM_ASS_INFO, len, val); |
| |
| return abis_rsl_sendmsg(bts, msg); |
| } |
| |
| /* Chapter 8.3.1 */ |
| int rsl_data_request(struct gsm_bts *bts, struct msgb *msg) |
| { |
| /* FIXME: prepend RSL header to layer 3 message */ |
| u_int8_t len = msg->len; |
| struct abis_rsl_rll_hdr *rh; |
| |
| msgb_tv_push(msg, RSL_IE_L3_INFO, len); |
| |
| rh = (struct abis_rsl_rll_hdr *) msgb_push(msg, sizeof(*rh)); |
| init_llm_hdr(rh, RSL_MT_DATA_REQ); |
| rh->chan_nr = RSL_CHAN_SDCCH4_ACCH; /* FIXME: don't harcode */ |
| |
| return abis_rsl_sendmsg(bts, msg); |
| } |
| |
| static int abis_rsl_rx_dchan(struct msgb *msg) |
| { |
| struct abis_rsl_common_hdr *rslh = msgb_l2(msg) ; |
| |
| switch (rslh->msg_type) { |
| case RSL_MT_CHAN_ACTIV_ACK: |
| case RSL_MT_CHAN_ACTIV_NACK: |
| case RSL_MT_CONN_FAIL: |
| case RSL_MT_MEAS_RES: |
| case RSL_MT_MODE_MODIFY_ACK: |
| case RSL_MT_MODE_MODIFY_NACK: |
| case RSL_MT_PHY_CONTEXT_CONF: |
| case RSL_MT_PREPROC_MEAS_RES: |
| case RSL_MT_RF_CHAN_REL_ACK: |
| case RSL_MT_TALKER_DET: |
| case RSL_MT_LISTENER_DET: |
| case RSL_MT_REMOTE_CODEC_CONF_REP: |
| case RSL_MT_MR_CODEC_MOD_ACK: |
| case RSL_MT_MR_CODEC_MOD_NACK: |
| case RSL_MT_MR_CODEC_MOD_PER: |
| fprintf(stderr, "Unimplemented Abis RSL DChan msg 0x%02x\n", |
| rslh->msg_type); |
| break; |
| default: |
| fprintf(stderr, "unknown Abis RSL DChan msg 0x%02x\n", |
| rslh->msg_type); |
| return -EINVAL; |
| } |
| } |
| |
| static int abis_rsl_rx_trx(struct msgb *msg) |
| { |
| struct abis_rsl_common_hdr *rslh = msgb_l2(msg) ; |
| |
| switch (rslh->msg_type) { |
| case RSL_MT_RF_RES_IND: |
| /* interference on idle channels of TRX */ |
| case RSL_MT_OVERLOAD: |
| /* indicate CCCH / ACCH / processor overload */ |
| case RSL_MT_ERROR_REPORT: |
| fprintf(stderr, "Unimplemented Abis RSL TRX message type 0x%02x\n", |
| rslh->msg_type); |
| break; |
| default: |
| fprintf(stderr, "Unknown Abis RSL TRX message type 0x%02x\n", |
| rslh->msg_type); |
| return -EINVAL; |
| } |
| |
| } |
| |
| static int rsl_rx_chan_rqd(struct msgb *msg) |
| { |
| struct gsm_bts *bts = msg->bts_link->bts; |
| struct gsm48_imm_ass ia; |
| u_int16_t arfcn; |
| u_int8_t ts_number, subch; |
| |
| /* MS has requested a channel on the RACH */ |
| /* parse channel number, request reference, access delay */ |
| /* FIXME: check permission/availability */ |
| ts_number = 0; |
| arfcn = HARDCODED_ARFCN; |
| subch = 0; |
| |
| /* send CHANNEL ACTIVATION on RSL to BTS */ |
| rsl_chan_activate_sdcch(&bts->trx[0].ts[ts_number]); |
| |
| /* create IMMEDIATE ASSIGN 04.08 messge */ |
| memset(&ia, 0, sizeof(ia)); |
| ia.l2_plen = 0x2d; |
| ia.proto_discr = GSM48_PDISC_RR; |
| ia.msg_type = GSM48_MT_RR_IMM_ASS; |
| ia.page_mode = GSM48_PM_NORMAL; |
| ia.chan_desc.chan_nr = rsl_enc_chan_nr(RSL_CHAN_SDCCH4_ACCH, subch, ts_number); |
| ia.chan_desc.h0.h = 0; |
| ia.chan_desc.h0.arfcn_high = arfcn >> 8; |
| ia.chan_desc.h0.arfcn_low = arfcn & 0xff; |
| ia.chan_desc.h0.tsc = 7; |
| /* FIXME: use real request reference extracted from CHAN_RQD */ |
| ia.req_ref.ra = 0x80 | 0x1e; |
| ia.req_ref.t2 = 0x0c; |
| ia.req_ref.t1_ = 0x12; |
| ia.req_ref.t3_low = 0x19 & 3; |
| ia.req_ref.t3_high = 0x19 >> 3; |
| ia.timing_advance = 0; |
| ia.mob_alloc_len = 0; |
| |
| /* send IMMEDIATE ASSIGN CMD on RSL to BTS (to send on CCCH to MS) */ |
| return rsl_imm_assign_cmd(bts, sizeof(ia), (u_int8_t *) &ia); |
| } |
| |
| static int abis_rsl_rx_cchan(struct msgb *msg) |
| { |
| struct abis_rsl_common_hdr *rslh = msgb_l2(msg) ; |
| int rc; |
| |
| switch (rslh->msg_type) { |
| case RSL_MT_CHAN_RQD: |
| /* MS has requested a channel on the RACH */ |
| rc = rsl_rx_chan_rqd(msg); |
| break; |
| case RSL_MT_DELETE_IND: |
| /* CCCH overloaded, IMM_ASSIGN was dropped */ |
| case RSL_MT_CBCH_LOAD_IND: |
| /* current load on the CBCH */ |
| case RSL_MT_CCCH_LOAD_IND: |
| /* current load on the CCCH */ |
| fprintf(stderr, "Unimplemented Abis RSL TRX message type 0x%02x\n", |
| rslh->msg_type); |
| break; |
| default: |
| fprintf(stderr, "Unknown Abis RSL TRX message type 0x%02x\n", |
| rslh->msg_type); |
| return -EINVAL; |
| } |
| } |
| |
| /* ESTABLISH INDICATION, LOCATION AREA UPDATE REQUEST |
| 0x02, 0x06, |
| 0x01, 0x20, |
| 0x02, 0x00, |
| 0x0b, 0x00, 0x0f, 0x05, 0x08, ... */ |
| |
| static int abis_rsl_rx_rll(struct msgb *msg) |
| { |
| struct abis_rsl_rll_hdr *rllh = msgb_l2(msg); |
| int rc; |
| |
| switch (rllh->c.msg_type) { |
| case RSL_MT_DATA_IND: |
| DEBUGP(DRLL, "DATA INDICATION\n"); |
| /* FIXME: parse L3 info element */ |
| rc = gsm0408_rcvmsg(msg); |
| break; |
| case RSL_MT_EST_IND: |
| DEBUGP(DRLL, "ESTABLISH INDICATION\n"); |
| /* FIXME: parse L3 info element */ |
| rc = gsm0408_rcvmsg(msg); |
| break; |
| case RSL_MT_ERROR_IND: |
| case RSL_MT_REL_IND: |
| case RSL_MT_UNIT_DATA_IND: |
| fprintf(stderr, "unimplemented Abis RLL message type 0x%02x\n", |
| rllh->c.msg_type); |
| break; |
| default: |
| fprintf(stderr, "unknown Abis RLL message type 0x%02x\n", |
| rllh->c.msg_type); |
| } |
| } |
| |
| /* Entry-point where L2 RSL from BTS enters */ |
| int abis_rsl_rx(struct msgb *msg) |
| { |
| struct abis_rsl_common_hdr *rslh = msgb_l2(msg) ; |
| unsigned int l2_len = (void *)msg->tail - msgb_l2(msg); |
| int rc; |
| |
| switch (rslh->msg_discr & 0xfe) { |
| case ABIS_RSL_MDISC_RLL: |
| rc = abis_rsl_rx_rll(msg); |
| break; |
| case ABIS_RSL_MDISC_DED_CHAN: |
| rc = abis_rsl_rx_dchan(msg); |
| break; |
| case ABIS_RSL_MDISC_COM_CHAN: |
| case ABIS_RSL_MDISC_TRX: |
| rc = abis_rsl_rx_cchan(msg); |
| break; |
| case ABIS_RSL_MDISC_LOC: |
| default: |
| fprintf(stderr, "unknown RSL message discriminator 0x%02x\n", |
| rslh->msg_discr); |
| return -EINVAL; |
| } |
| } |