diff options
Diffstat (limited to 'src/host/layer23/src/misc/layer3.c')
| -rw-r--r-- | src/host/layer23/src/misc/layer3.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/src/host/layer23/src/misc/layer3.c b/src/host/layer23/src/misc/layer3.c new file mode 100644 index 00000000..69f558d7 --- /dev/null +++ b/src/host/layer23/src/misc/layer3.c @@ -0,0 +1,235 @@ +#include <stdint.h> +#include <errno.h> +#include <stdio.h> + +#include <osmocore/msgb.h> +#include <osmocore/rsl.h> +#include <osmocore/tlv.h> +#include <osmocore/protocol/gsm_04_08.h> + +#include <osmocom/bb/common/logging.h> +#include <osmocom/bb/common/lapdm.h> +#include <osmocom/bb/misc/rslms.h> +#include <osmocom/bb/misc/layer3.h> +#include <osmocom/bb/common/osmocom_data.h> +#include <osmocom/bb/common/l1ctl.h> + +static int ccch_mode = CCCH_MODE_NONE; + +static void dump_bcch(struct osmocom_ms *ms, uint8_t tc, const uint8_t *data) +{ + struct gsm48_system_information_type_header *si_hdr; + si_hdr = (struct gsm48_system_information_type_header *) data; + + /* GSM 05.02 ยง6.3.1.3 Mapping of BCCH data */ + switch (si_hdr->system_information) { + case GSM48_MT_RR_SYSINFO_1: + fprintf(stderr, "\tSI1"); +#ifdef BCCH_TC_CHECK + if (tc != 0) + fprintf(stderr, " on wrong TC"); +#endif + break; + case GSM48_MT_RR_SYSINFO_2: + fprintf(stderr, "\tSI2"); +#ifdef BCCH_TC_CHECK + if (tc != 1) + fprintf(stderr, " on wrong TC"); +#endif + break; + case GSM48_MT_RR_SYSINFO_3: + fprintf(stderr, "\tSI3"); +#ifdef BCCH_TC_CHECK + if (tc != 2 && tc != 6) + fprintf(stderr, " on wrong TC"); +#endif + if (ccch_mode == CCCH_MODE_NONE) { + struct gsm48_system_information_type_3 *si3 = + (struct gsm48_system_information_type_3 *)data; + + if (si3->control_channel_desc.ccch_conf == RSL_BCCH_CCCH_CONF_1_C) + ccch_mode = CCCH_MODE_COMBINED; + else + ccch_mode = CCCH_MODE_NON_COMBINED; + + l1ctl_tx_ccch_mode_req(ms, ccch_mode); + } + break; + case GSM48_MT_RR_SYSINFO_4: + fprintf(stderr, "\tSI4"); +#ifdef BCCH_TC_CHECK + if (tc != 3 && tc != 7) + fprintf(stderr, " on wrong TC"); +#endif + break; + case GSM48_MT_RR_SYSINFO_5: + fprintf(stderr, "\tSI5"); + break; + case GSM48_MT_RR_SYSINFO_6: + fprintf(stderr, "\tSI6"); + break; + case GSM48_MT_RR_SYSINFO_7: + fprintf(stderr, "\tSI7"); +#ifdef BCCH_TC_CHECK + if (tc != 7) + fprintf(stderr, " on wrong TC"); +#endif + break; + case GSM48_MT_RR_SYSINFO_8: + fprintf(stderr, "\tSI8"); +#ifdef BCCH_TC_CHECK + if (tc != 3) + fprintf(stderr, " on wrong TC"); +#endif + break; + case GSM48_MT_RR_SYSINFO_9: + fprintf(stderr, "\tSI9"); +#ifdef BCCH_TC_CHECK + if (tc != 4) + fprintf(stderr, " on wrong TC"); +#endif + break; + case GSM48_MT_RR_SYSINFO_13: + fprintf(stderr, "\tSI13"); +#ifdef BCCH_TC_CHECK + if (tc != 4 && tc != 0) + fprintf(stderr, " on wrong TC"); +#endif + break; + case GSM48_MT_RR_SYSINFO_16: + fprintf(stderr, "\tSI16"); +#ifdef BCCH_TC_CHECK + if (tc != 6) + fprintf(stderr, " on wrong TC"); +#endif + break; + case GSM48_MT_RR_SYSINFO_17: + fprintf(stderr, "\tSI17"); +#ifdef BCCH_TC_CHECK + if (tc != 2) + fprintf(stderr, " on wrong TC"); +#endif + break; + case GSM48_MT_RR_SYSINFO_2bis: + fprintf(stderr, "\tSI2bis"); +#ifdef BCCH_TC_CHECK + if (tc != 5) + fprintf(stderr, " on wrong TC"); +#endif + break; + case GSM48_MT_RR_SYSINFO_2ter: + fprintf(stderr, "\tSI2ter"); +#ifdef BCCH_TC_CHECK + if (tc != 5 && tc != 4) + fprintf(stderr, " on wrong TC"); +#endif + break; + case GSM48_MT_RR_SYSINFO_5bis: + fprintf(stderr, "\tSI5bis"); + break; + case GSM48_MT_RR_SYSINFO_5ter: + fprintf(stderr, "\tSI5ter"); + break; + default: + fprintf(stderr, "\tUnknown SI"); + break; + }; + + fprintf(stderr, "\n"); +} + + +/* send location updating request * (as part of RSLms EST IND / + LAPDm SABME) */ +static int gsm48_tx_loc_upd_req(struct osmocom_ms *ms, uint8_t chan_nr) +{ + struct msgb *msg = msgb_alloc_headroom(256, 16, "loc_upd_req"); + struct gsm48_hdr *gh; + struct gsm48_loc_upd_req *lu_r; + + DEBUGP(DMM, "chan_nr=%u\n", chan_nr); + + msg->l3h = msgb_put(msg, sizeof(*gh)); + gh = (struct gsm48_hdr *) msg->l3h; + gh->proto_discr = GSM48_PDISC_MM; + gh->msg_type = GSM48_MT_MM_LOC_UPD_REQUEST; + lu_r = (struct gsm48_loc_upd_req *) msgb_put(msg, sizeof(*lu_r)); + lu_r->type = GSM48_LUPD_IMSI_ATT; + lu_r->key_seq = 0; + /* FIXME: set LAI and CM1 */ + /* FIXME: set MI */ + lu_r->mi_len = 0; + + return rslms_tx_rll_req_l3(ms, RSL_MT_EST_REQ, chan_nr, 0, msg); +} + +static int gsm48_rx_imm_ass(struct msgb *msg, struct osmocom_ms *ms) +{ + struct gsm48_imm_ass *ia = msgb_l3(msg); + uint8_t ch_type, ch_subch, ch_ts; + uint16_t arfcn; + + rsl_dec_chan_nr(ia->chan_desc.chan_nr, &ch_type, &ch_subch, &ch_ts); + arfcn = ia->chan_desc.h0.arfcn_low | (ia->chan_desc.h0.arfcn_high << 8); + + DEBUGP(DRR, "GSM48 IMM ASS (ra=0x%02x, chan_nr=0x%02x, " + "ARFCN=%u, TS=%u, SS=%u, TSC=%u) ", ia->req_ref.ra, + ia->chan_desc.chan_nr, arfcn, ch_ts, ch_subch, + ia->chan_desc.h0.tsc); + + /* FIXME: compare RA and GSM time with when we sent RACH req */ + + /* check if we can support this type of channel at the moment */ + if (ch_type != RSL_CHAN_SDCCH4_ACCH || ch_ts != 0 || + ia->chan_desc.h0.h == 1) { + DEBUGPC(DRR, "UNSUPPORTED!\n"); + return 0; + } + + /* request L1 to go to dedicated mode on assigned channel */ + l1ctl_tx_dm_est_req_h0(ms, arfcn, ia->chan_desc.chan_nr, + ia->chan_desc.h0.tsc); + + /* request L2 to establish the SAPI0 connection */ + gsm48_tx_loc_upd_req(ms, ia->chan_desc.chan_nr); + + DEBUGPC(DRR, "\n"); + + return 0; +} + +int gsm48_rx_ccch(struct msgb *msg, struct osmocom_ms *ms) +{ + struct gsm48_system_information_type_header *sih = msgb_l3(msg); + int rc = 0; + + if (sih->rr_protocol_discriminator != GSM48_PDISC_RR) + LOGP(DRR, LOGL_ERROR, "PCH pdisc != RR\n"); + + switch (sih->system_information) { + case GSM48_MT_RR_PAG_REQ_1: + case GSM48_MT_RR_PAG_REQ_2: + case GSM48_MT_RR_PAG_REQ_3: + /* FIXME: implement decoding of paging request */ + break; + case GSM48_MT_RR_IMM_ASS: + rc = gsm48_rx_imm_ass(msg, ms); + break; + default: + LOGP(DRR, LOGL_NOTICE, "unknown PCH/AGCH type 0x%02x\n", + sih->system_information); + rc = -EINVAL; + } + + return rc; +} + +int gsm48_rx_bcch(struct msgb *msg, struct osmocom_ms *ms) +{ + /* FIXME: we have lost the gsm frame time until here, need to store it + * in some msgb context */ + //dump_bcch(dl->time.tc, ccch->data); + dump_bcch(ms, 0, msg->l3h); + + return 0; +} |