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-rw-r--r--src/abis_rsl.c508
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diff --git a/src/abis_rsl.c b/src/abis_rsl.c
new file mode 100644
index 00000000..f503684f
--- /dev/null
+++ b/src/abis_rsl.c
@@ -0,0 +1,508 @@
+/* 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;
+ }
+}