diff options
| -rw-r--r-- | src/osmo-bsc/lchan_fsm.c | 124 | ||||
| -rw-r--r-- | tests/handover/handover_test.c | 6 |
2 files changed, 72 insertions, 58 deletions
diff --git a/src/osmo-bsc/lchan_fsm.c b/src/osmo-bsc/lchan_fsm.c index 39edaff6d..915b62aff 100644 --- a/src/osmo-bsc/lchan_fsm.c +++ b/src/osmo-bsc/lchan_fsm.c @@ -36,6 +36,8 @@ #include <osmocom/bsc/assignment_fsm.h> #include <osmocom/bsc/handover_fsm.h> #include <osmocom/bsc/bsc_msc_data.h> +#include <osmocom/bsc/codec_pref.h> + static struct osmo_fsm lchan_fsm; @@ -402,66 +404,71 @@ static void lchan_fsm_unused_onenter(struct osmo_fsm_inst *fi, uint32_t prev_sta osmo_fsm_inst_dispatch(lchan->ts->fi, TS_EV_LCHAN_UNUSED, lchan); } -/*! Configure the multirate setting on this channel. */ -void lchan_mr_config(struct gsm_lchan *lchan, struct gsm48_multi_rate_conf *mr_conf) +/* Configure the multirate setting on this channel. */ +static int lchan_mr_config(struct gsm_lchan *lchan, const struct gsm48_multi_rate_conf *mr_conf) { - struct gsm48_multi_rate_conf *ms_conf, *bts_conf; bool full_rate = (lchan->type == GSM_LCHAN_TCH_F); + struct gsm_bts *bts = lchan->ts->trx->bts; + struct bsc_msc_data *msc = lchan->conn->sccp.msc; + struct amr_multirate_conf *mr; + int rc; + int rc_rate; + struct gsm48_multi_rate_conf mr_conf_filtered; + const struct gsm48_multi_rate_conf *mr_conf_bts; + + /* There are two different active sets, depending on the channel rate, + * make sure the appropate one is selected. */ + if (full_rate) + mr = &bts->mr_full; + else + mr = &bts->mr_half; + + /* The VTY allows to forbid certain codec rates. Unfortunately we can + * not articulate all of the prohibitions on through S0-S15 on the A + * interface. To ensure that the VTY settings are observed we create + * a manipulated copy of the mr_conf that ensures forbidden codec rates + * are not used in the multirate configuration IE. */ + rc_rate = calc_amr_rate_intersection(&mr_conf_filtered, &msc->amr_conf, mr_conf); + if (rc_rate < 0) { + LOG_LCHAN(lchan, LOGL_ERROR, + "can not encode multirate configuration (invalid amr rate setting, MSC)\n"); + return -EINVAL; + } - /* initialize the data structure */ - lchan->mr_ms_lv[0] = sizeof(*ms_conf); - lchan->mr_bts_lv[0] = sizeof(*bts_conf); - ms_conf = (struct gsm48_multi_rate_conf *) &lchan->mr_ms_lv[1]; - bts_conf = (struct gsm48_multi_rate_conf *) &lchan->mr_bts_lv[1]; - - *ms_conf = *bts_conf = (struct gsm48_multi_rate_conf){ - .ver = 1, - .icmi = 1, - .m4_75 = mr_conf->m4_75, - .m5_15 = mr_conf->m5_15, - .m5_90 = mr_conf->m5_90, - .m6_70 = mr_conf->m6_70, - .m7_40 = mr_conf->m7_40, - .m7_95 = mr_conf->m7_95, - .m10_2 = full_rate? mr_conf->m10_2 : 0, - .m12_2 = full_rate? mr_conf->m12_2 : 0, - }; -} + /* The two last codec rates which are defined for AMR do only work with + * full rate channels. We will pinch off those rates für half-rate + * channels to ensure they are not included accidently. */ + if (!full_rate) { + if (mr_conf_filtered.m10_2 || mr_conf_filtered.m12_2) + LOG_LCHAN(lchan, LOGL_ERROR, "ignoring unsupported amr codec rates\n"); + mr_conf_filtered.m10_2 = 0; + mr_conf_filtered.m12_2 = 0; + } -/* Mask all rates instead of the highest possible */ -static void lchan_mr_config_mask(struct gsm48_multi_rate_conf *mr_conf) -{ - unsigned int i; - bool highest_seen = false; - uint8_t *_mr_conf = (uint8_t *) mr_conf; - - /* FIXME: At the moment we can not support multiple codec rates in one - * struct gsm48_multi_rate_conf, because the struct lacks the fields - * for Threshold and Hysteresis. Those fields are not needed when only - * a single codec rate is in place, but as soon as multiple codec - * rates are used the parameters are mandatory. The layout for the - * struct would then also be different because each rate needs its - * own Threshold and Hysteresis value. (See also 3GPP TS 04.08, - * chapter 10.5.2.21aa MultiRate configuration). - * - * Since we are unable to signal multiple codec rates properly, we just - * remove all codec rates from the active set, except the highest - * possible. Doing so we lack the functionality to switch towards the - * other, lower codec rates that were offered by the MSC, but it is - * still guaranteed that a rate is selected that is supported by all - * entities. - * - * To fix this problem, we should implement a proper encoder for - * struct gsm48_multi_rate_conf, in libosmocore and use it here. - * struct amr_mode already seems to have members for threshold and - * hysteresis we can use. */ - - for (i = 7; i > 0; i--) { - if (_mr_conf[1] & (1 << i) && highest_seen == false) { - highest_seen = true; - } else if (highest_seen) - _mr_conf[1] &= ~(1 << i); + /* Ensure that the resulting filtered conf is coherent with the + * configuration that is set for the BTS and the specified rate */ + mr_conf_bts = (struct gsm48_multi_rate_conf *)mr->gsm48_ie; + rc_rate = calc_amr_rate_intersection(&mr_conf_filtered, mr_conf_bts, &mr_conf_filtered); + if (rc_rate < 0) { + LOG_LCHAN(lchan, LOGL_ERROR, + "can not encode multirate configuration (invalid amr rate setting, BTS)\n"); + return -EINVAL; } + + /* Proceed with the generation of the multirate configuration IE + * (MS and BTS) */ + rc = gsm48_multirate_config(lchan->mr_ms_lv, &mr_conf_filtered, mr->ms_mode, mr->num_modes); + if (rc != 0) { + LOG_LCHAN(lchan, LOGL_ERROR, "can not encode multirate configuration (MS)\n"); + return -EINVAL; + } + rc = gsm48_multirate_config(lchan->mr_bts_lv, &mr_conf_filtered, mr->bts_mode, mr->num_modes); + if (rc != 0) { + LOG_LCHAN(lchan, LOGL_ERROR, "can not encode multirate configuration (BTS)\n"); + return -EINVAL; + } + + return 0; } static void lchan_fsm_unused(struct osmo_fsm_inst *fi, uint32_t event, void *data) @@ -511,9 +518,10 @@ static void lchan_fsm_unused(struct osmo_fsm_inst *fi, uint32_t event, void *dat if (info->chan_mode == GSM48_CMODE_SPEECH_AMR) { gsm48_mr_cfg_from_gsm0808_sc_cfg(&mr_conf, info->s15_s0); - /* FIXME: See above. */ - lchan_mr_config_mask(&mr_conf); - lchan_mr_config(lchan, &mr_conf); + if (lchan_mr_config(lchan, &mr_conf) < 0) { + lchan_fail("Can not generate multirate configuration IE\n"); + return; + } } switch (info->chan_mode) { diff --git a/tests/handover/handover_test.c b/tests/handover/handover_test.c index 76e5fe132..7cb4086bb 100644 --- a/tests/handover/handover_test.c +++ b/tests/handover/handover_test.c @@ -224,6 +224,12 @@ void create_conn(struct gsm_lchan *lchan) struct gsm_network *net = lchan->ts->trx->bts->network; struct gsm_subscriber_connection *conn; struct mgcp_client *fake_mgcp_client = (void*)talloc_zero(net, int); + uint8_t *amr_conf; + + /* HACK: lchan_fsm.c requires some AMR codec rates to be enabled, + * lets pretend that all AMR codec rates are allowed */ + amr_conf = (uint8_t*) &fake_msc_data.amr_conf; + amr_conf[1] = 0xff; conn = bsc_subscr_con_allocate(net); |