| /* GSM Mobile Radio Interface Layer 3 messages on the A-bis interface |
| * 3GPP TS 04.08 version 7.21.0 Release 1998 / ETSI TS 100 940 V7.21.0 */ |
| |
| /* (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 <stdlib.h> |
| #include <string.h> |
| #include <errno.h> |
| #include <netinet/in.h> |
| |
| #include <openbsc/msgb.h> |
| #include <openbsc/debug.h> |
| #include <openbsc/gsm_data.h> |
| #include <openbsc/gsm_subscriber.h> |
| #include <openbsc/gsm_04_08.h> |
| #include <openbsc/abis_rsl.h> |
| |
| #define GSM48_ALLOC_SIZE 1024 |
| #define GSM48_ALLOC_HEADROOM 128 |
| |
| struct gsm_lai { |
| u_int16_t mcc; |
| u_int16_t mnc; |
| u_int16_t lac; |
| }; |
| |
| static void parse_lai(struct gsm_lai *lai, const struct gsm48_loc_area_id *lai48) |
| { |
| u_int8_t dig[4]; |
| |
| /* MCC */ |
| dig[1] = lai48->digits[0] & 0x0f; |
| dig[2] = lai48->digits[0] >> 4; |
| dig[3] = lai48->digits[1] & 0x0f; |
| lai->mcc = dig[3] * 100 + dig[2]; |
| |
| /* MNC */ |
| dig[1] = lai48->digits[1] >> 4; |
| dig[2] = lai48->digits[2] & 0x0f; |
| dig[3] = lai48->digits[2] >> 4; |
| lai->mnc = dig[3] * 100 + dig[2]; |
| |
| lai->lac = lai48->lac; |
| } |
| |
| static void to_bcd(u_int8_t *bcd, u_int16_t val) |
| { |
| bcd[2] = val % 10; |
| val = val / 10; |
| bcd[1] = val % 10; |
| val = val / 10; |
| bcd[0] = val % 10; |
| val = val / 10; |
| } |
| |
| static void generate_lai(struct gsm48_loc_area_id *lai48, u_int16_t mcc, |
| u_int16_t mnc, u_int16_t lac) |
| { |
| u_int8_t bcd[3]; |
| |
| to_bcd(bcd, mcc); |
| lai48->digits[0] = bcd[0] | (bcd[1] << 4); |
| lai48->digits[1] = bcd[2]; |
| |
| to_bcd(bcd, mnc); |
| /* FIXME: do we need three-digit MNC? See Table 10.5.3 */ |
| #if 0 |
| lai48->digits[1] |= bcd[2] << 4; |
| lai48->digits[2] = bcd[0] | (bcd[1] << 4); |
| #else |
| lai48->digits[1] |= 0xf << 4; |
| lai48->digits[2] = bcd[1] | (bcd[2] << 4); |
| #endif |
| |
| lai48->lac = htons(lac); |
| } |
| |
| #define TMSI_LEN 4 |
| #define MID_TMSI_LEN (TMSI_LEN + 2) |
| |
| static void generate_mid_from_tmsi(u_int8_t *buf, u_int8_t *tmsi_bcd) |
| { |
| buf[0] = GSM48_IE_MOBILE_ID; |
| buf[1] = MID_TMSI_LEN; |
| buf[2] = 0xf0 | GSM_MI_TYPE_TMSI; |
| buf[3] = tmsi_bcd[0]; |
| buf[4] = tmsi_bcd[1]; |
| buf[5] = tmsi_bcd[2]; |
| buf[6] = tmsi_bcd[3]; |
| } |
| |
| static struct msgb *gsm48_msgb_alloc(void) |
| { |
| return msgb_alloc_headroom(GSM48_ALLOC_SIZE, GSM48_ALLOC_HEADROOM); |
| } |
| |
| static int gsm0408_sendmsg(struct msgb *msg) |
| { |
| if (msg->lchan) |
| msg->trx = msg->lchan->ts->trx; |
| |
| msg->l3h = msg->data; |
| |
| return rsl_data_request(msg, 0); |
| } |
| |
| static int gsm48_cc_tx_status(struct gsm_lchan *lchan) |
| { |
| struct msgb *msg = gsm48_msgb_alloc(); |
| struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh)); |
| u_int8_t *cause, *call_state; |
| |
| msg->lchan = lchan; |
| |
| gh->proto_discr = GSM48_PDISC_CC; |
| gh->msg_type = GSM48_MT_CC_STATUS; |
| |
| cause = msgb_put(msg, 3); |
| cause[0] = 2; |
| cause[1] = GSM48_CAUSE_CS_GSM | GSM48_CAUSE_LOC_USER; |
| cause[2] = 0x80 | 30; /* response to status inquiry */ |
| |
| call_state = msgb_put(msg, 1); |
| call_state[0] = 0xc0 | 0x00; |
| |
| return gsm0408_sendmsg(msg); |
| } |
| |
| static int gsm48_cc_rx_status_enq(struct msgb *msg) |
| { |
| return gsm48_cc_tx_status(msg->lchan); |
| } |
| |
| static int gsm0408_rcv_cc(struct msgb *msg) |
| { |
| struct gsm48_hdr *gh = msgb_l3(msg); |
| u_int8_t msg_type = gh->msg_type & 0xbf; |
| int rc = 0; |
| |
| switch (msg_type) { |
| case GSM48_MT_CC_CALL_CONF: |
| /* Response to SETUP */ |
| DEBUGP(DCC, "CALL CONFIRM\n"); |
| break; |
| case GSM48_MT_CC_RELEASE_COMPL: |
| DEBUGP(DCC, "RELEASE COMPLETE\n"); |
| break; |
| case GSM48_MT_CC_ALERTING: |
| DEBUGP(DCC, "ALERTING\n"); |
| break; |
| case GSM48_MT_CC_CONNECT: |
| DEBUGP(DCC, "CONNECT\n"); |
| /* need to respond with CONNECT_ACK */ |
| break; |
| case GSM48_MT_CC_RELEASE: |
| DEBUGP(DCC, "RELEASE\n"); |
| /* need to respond with RELEASE_COMPLETE */ |
| break; |
| case GSM48_MT_CC_STATUS_ENQ: |
| rc = gsm48_cc_rx_status_enq(msg); |
| break; |
| case GSM48_MT_CC_DISCONNECT: |
| DEBUGP(DCC, "DISCONNECT\n"); |
| break; |
| case GSM48_MT_CC_SETUP: |
| DEBUGP(DCC, "SETUP\n"); |
| /* FIXME: continue with CALL_PROCEEDING, ALERTING, CONNECT, RELEASE_COMPLETE */ |
| break; |
| case GSM48_MT_CC_EMERG_SETUP: |
| DEBUGP(DCC, "EMERGENCY SETUP\n"); |
| /* FIXME: continue with CALL_PROCEEDING, ALERTING, CONNECT, RELEASE_COMPLETE */ |
| break; |
| default: |
| fprintf(stderr, "Unimplemented GSM 04.08 msg type 0x%02x\n", |
| msg_type); |
| break; |
| } |
| |
| return rc; |
| } |
| |
| /* Chapter 9.2.14 : Send LOCATION UPDATE REJECT */ |
| int gsm0408_loc_upd_rej(struct gsm_lchan *lchan, u_int8_t cause) |
| { |
| struct msgb *msg = gsm48_msgb_alloc(); |
| struct gsm48_hdr *gh; |
| |
| msg->lchan = lchan; |
| |
| gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1); |
| gh->proto_discr = GSM48_PDISC_MM; |
| gh->msg_type = GSM48_MT_MM_LOC_UPD_ACCEPT; |
| gh->data[0] = cause; |
| |
| DEBUGP(DMM, "-> LOCATION UPDATE REJECT\n"); |
| |
| return gsm0408_sendmsg(msg); |
| } |
| |
| /* Chapter 9.2.13 : Send LOCATION UPDATE ACCEPT */ |
| int gsm0408_loc_upd_acc(struct gsm_lchan *lchan, u_int8_t *tmsi) |
| { |
| struct gsm_bts *bts = lchan->ts->trx->bts; |
| struct msgb *msg = gsm48_msgb_alloc(); |
| struct gsm48_hdr *gh; |
| struct gsm48_loc_area_id *lai; |
| u_int8_t *mid; |
| |
| msg->lchan = lchan; |
| |
| gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh)); |
| gh->proto_discr = GSM48_PDISC_MM; |
| gh->msg_type = GSM48_MT_MM_LOC_UPD_ACCEPT; |
| |
| lai = (struct gsm48_loc_area_id *) msgb_put(msg, sizeof(*lai)); |
| generate_lai(lai, bts->network->country_code, |
| bts->network->network_code, bts->location_area_code); |
| |
| mid = msgb_put(msg, MID_TMSI_LEN); |
| generate_mid_from_tmsi(mid, tmsi); |
| |
| DEBUGP(DMM, "-> LOCATION UPDATE ACCEPT\n"); |
| |
| return gsm0408_sendmsg(msg); |
| } |
| |
| /* Chapter 9.2.15 */ |
| static int mm_loc_upd_req(struct msgb *msg) |
| { |
| struct gsm48_hdr *gh = msgb_l3(msg); |
| struct gsm_bts *bts = msg->trx->bts; |
| struct gsm48_loc_upd_req *lu; |
| struct gsm_subscriber *subscr; |
| u_int8_t mi_type; |
| |
| lu = (struct gsm48_loc_upd_req *) gh->data; |
| |
| mi_type = lu->mi[0] & GSM_MI_TYPE_MASK; |
| |
| DEBUGP(DMM, "LUPDREQ: mi_type = 0x%02x\n", mi_type); |
| switch (mi_type) { |
| case GSM_MI_TYPE_IMSI: |
| /* look up subscriber based on IMSI */ |
| subscr = subscr_get_by_imsi(&lu->mi[1]); |
| break; |
| case GSM_MI_TYPE_TMSI: |
| /* look up the subscriber based on TMSI, request IMSI if it fails */ |
| subscr = subscr_get_by_tmsi(&lu->mi[1]); |
| if (!subscr) { |
| /* FIXME: send IDENTITY REQUEST message to get IMSI */ |
| //gsm0408_identity_request(...GSM_MI_TYPE_IMSI); |
| } |
| break; |
| case GSM_MI_TYPE_IMEI: |
| case GSM_MI_TYPE_IMEISV: |
| /* no sim card... FIXME: what to do ? */ |
| fprintf(stderr, "Unimplemented mobile identity type\n"); |
| break; |
| default: |
| fprintf(stderr, "Unknown mobile identity type\n"); |
| break; |
| } |
| |
| if (!subscr) { |
| /* 0x16 is congestion */ |
| gsm0408_loc_upd_rej(msg->lchan, 0x16); |
| return -EINVAL; |
| } |
| |
| msg->lchan->subscr = subscr; |
| subscr_update(subscr, bts); |
| |
| return gsm0408_loc_upd_acc(msg->lchan, subscr->tmsi); |
| } |
| |
| static int gsm48_tx_mm_serv_ack(struct gsm_lchan *lchan) |
| { |
| struct msgb *msg = gsm48_msgb_alloc(); |
| struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh)); |
| |
| msg->lchan = lchan; |
| |
| gh->proto_discr = GSM48_PDISC_MM; |
| gh->msg_type = GSM48_MT_MM_CM_SERV_ACC; |
| |
| DEBUGP(DMM, "-> CM SERVICE ACK\n"); |
| |
| return gsm0408_sendmsg(msg); |
| } |
| |
| static int gsm48_rx_mm_serv_req(struct msgb *msg) |
| { |
| struct gsm48_hdr *gh = msgb_l3(msg); |
| |
| DEBUGP(DMM, "CM SERVICE REQUEST\n"); |
| return gsm48_tx_mm_serv_ack(msg->lchan); |
| } |
| |
| static int gsm0408_rcv_mm(struct msgb *msg) |
| { |
| struct gsm48_hdr *gh = msgb_l3(msg); |
| int rc; |
| |
| switch (gh->msg_type & 0xbf) { |
| case GSM48_MT_MM_LOC_UPD_REQUEST: |
| DEBUGP(DMM, "LOCATION UPDATE REQUEST\n"); |
| rc = mm_loc_upd_req(msg); |
| break; |
| case GSM48_MT_MM_ID_RESP: |
| case GSM48_MT_MM_TMSI_REALL_COMPL: |
| case GSM48_MT_MM_AUTH_RESP: |
| case GSM48_MT_MM_IMSI_DETACH_IND: |
| case GSM48_MT_MM_CM_SERV_REQ: |
| rc = gsm48_rx_mm_serv_req(msg); |
| break; |
| case GSM48_MT_MM_CM_REEST_REQ: |
| fprintf(stderr, "Unimplemented GSM 04.08 MM msg type 0x%02x\n", |
| gh->msg_type); |
| break; |
| default: |
| fprintf(stderr, "Unknown GSM 04.08 MM msg type 0x%02x\n", |
| gh->msg_type); |
| break; |
| } |
| |
| return rc; |
| } |
| static int gsm0408_rcv_rr(struct msgb *msg) |
| { |
| struct gsm48_hdr *gh = msgb_l3(msg); |
| |
| switch (gh->msg_type) { |
| case GSM48_MT_RR_CLSM_CHG: |
| DEBUGP(DRR, "CLASSMARK CHANGE\n"); |
| /* FIXME: what to do ?!? */ |
| break; |
| case GSM48_MT_RR_PAG_RESP: |
| default: |
| fprintf(stderr, "Unimplemented GSM 04.08 msg type 0x%02x\n", |
| gh->msg_type); |
| break; |
| } |
| |
| return 0; |
| } |
| |
| /* here we pass in a msgb from the RSL->RLL. We expect the l3 pointer to be set */ |
| int gsm0408_rcvmsg(struct msgb *msg) |
| { |
| struct gsm48_hdr *gh = msgb_l3(msg); |
| u_int8_t pdisc = gh->proto_discr & 0x0f; |
| int rc = 0; |
| |
| switch (pdisc) { |
| case GSM48_PDISC_CC: |
| rc = gsm0408_rcv_cc(msg); |
| break; |
| case GSM48_PDISC_MM: |
| rc = gsm0408_rcv_mm(msg); |
| break; |
| case GSM48_PDISC_RR: |
| rc = gsm0408_rcv_rr(msg); |
| break; |
| case GSM48_PDISC_MM_GPRS: |
| case GSM48_PDISC_SM: |
| fprintf(stderr, "Unimplemented GSM 04.08 discriminator 0x%02d\n", |
| pdisc); |
| break; |
| default: |
| fprintf(stderr, "Unknown GSM 04.08 discriminator 0x%02d\n", |
| pdisc); |
| break; |
| } |
| |
| return rc; |
| } |
| |
| enum chreq_type { |
| CHREQ_T_EMERG_CALL, |
| CHREQ_T_CALL_REEST_TCH_F, |
| CHREQ_T_CALL_REEST_TCH_H, |
| CHREQ_T_CALL_REEST_TCH_H_DBL, |
| CHREQ_T_SDCCH, |
| CHREQ_T_TCH_F, |
| CHREQ_T_VOICE_CALL_TCH_H, |
| CHREQ_T_DATA_CALL_TCH_H, |
| CHREQ_T_LOCATION_UPD, |
| CHREQ_T_PAG_R_ANY, |
| CHREQ_T_PAG_R_TCH_F, |
| CHREQ_T_PAG_R_TCH_FH, |
| }; |
| |
| /* Section 9.1.8 / Table 9.9 */ |
| struct chreq { |
| u_int8_t val; |
| u_int8_t mask; |
| enum chreq_type type; |
| }; |
| |
| /* If SYSTEM INFORMATION TYPE 4 NECI bit == 1 */ |
| static const struct chreq chreq_type_neci1[] = { |
| { 0xa0, 0xe0, CHREQ_T_EMERG_CALL }, |
| { 0xc0, 0xe0, CHREQ_T_CALL_REEST_TCH_F }, |
| { 0x68, 0xfc, CHREQ_T_CALL_REEST_TCH_H }, |
| { 0x6c, 0xfc, CHREQ_T_CALL_REEST_TCH_H_DBL }, |
| { 0xe0, 0xe0, CHREQ_T_SDCCH }, |
| { 0x40, 0xf0, CHREQ_T_VOICE_CALL_TCH_H }, |
| { 0x50, 0xf0, CHREQ_T_DATA_CALL_TCH_H }, |
| { 0x00, 0xf0, CHREQ_T_LOCATION_UPD }, |
| { 0x10, 0xf0, CHREQ_T_SDCCH }, |
| { 0x80, 0xe0, CHREQ_T_PAG_R_ANY }, |
| { 0x20, 0xf0, CHREQ_T_PAG_R_TCH_F }, |
| { 0x30, 0xf0, CHREQ_T_PAG_R_TCH_FH }, |
| }; |
| |
| /* If SYSTEM INFORMATION TYPE 4 NECI bit == 0 */ |
| static const struct chreq chreq_type_neci0[] = { |
| { 0xa0, 0xe0, CHREQ_T_EMERG_CALL }, |
| { 0xc0, 0xe0, CHREQ_T_CALL_REEST_TCH_H }, |
| { 0xe0, 0xe0, CHREQ_T_TCH_F }, |
| { 0x50, 0xf0, CHREQ_T_DATA_CALL_TCH_H }, |
| { 0x00, 0xe0, CHREQ_T_LOCATION_UPD }, |
| { 0x80, 0xe0, CHREQ_T_PAG_R_ANY }, |
| { 0x20, 0xf0, CHREQ_T_PAG_R_TCH_F }, |
| { 0x30, 0xf0, CHREQ_T_PAG_R_TCH_FH }, |
| }; |
| |
| static const enum gsm_chan_t ctype_by_chreq[] = { |
| [CHREQ_T_EMERG_CALL] = GSM_LCHAN_TCH_F, |
| [CHREQ_T_CALL_REEST_TCH_F] = GSM_LCHAN_TCH_F, |
| [CHREQ_T_CALL_REEST_TCH_H] = GSM_LCHAN_TCH_H, |
| [CHREQ_T_CALL_REEST_TCH_H_DBL] = GSM_LCHAN_TCH_H, |
| [CHREQ_T_SDCCH] = GSM_LCHAN_SDCCH, |
| [CHREQ_T_TCH_F] = GSM_LCHAN_TCH_F, |
| [CHREQ_T_VOICE_CALL_TCH_H] = GSM_LCHAN_TCH_H, |
| [CHREQ_T_DATA_CALL_TCH_H] = GSM_LCHAN_TCH_H, |
| [CHREQ_T_LOCATION_UPD] = GSM_LCHAN_SDCCH, |
| [CHREQ_T_PAG_R_ANY] = GSM_LCHAN_SDCCH, |
| [CHREQ_T_PAG_R_TCH_F] = GSM_LCHAN_TCH_F, |
| [CHREQ_T_PAG_R_TCH_FH] = GSM_LCHAN_TCH_F, |
| }; |
| |
| enum gsm_chan_t get_ctype_by_chreq(struct gsm_bts *bts, u_int8_t ra) |
| { |
| int i; |
| /* FIXME: determine if we set NECI = 0 in the BTS SI4 */ |
| |
| for (i = 0; i < ARRAY_SIZE(chreq_type_neci0); i++) { |
| const struct chreq *chr = &chreq_type_neci0[i]; |
| if ((ra & chr->mask) == chr->val) |
| return ctype_by_chreq[chr->type]; |
| } |
| fprintf(stderr, "Unknown CHANNEL REQUEST RQD 0x%02x\n", ra); |
| return GSM_LCHAN_SDCCH; |
| } |