diff options
-rw-r--r-- | include/osmocom/msc/Makefile.am | 2 | ||||
-rw-r--r-- | include/osmocom/msc/csd_bs.h | 54 | ||||
-rw-r--r-- | include/osmocom/msc/csd_filter.h | 53 | ||||
-rw-r--r-- | include/osmocom/msc/sdp_msg.h | 5 | ||||
-rw-r--r-- | include/osmocom/msc/transaction.h | 4 | ||||
-rw-r--r-- | src/libmsc/Makefile.am | 2 | ||||
-rw-r--r-- | src/libmsc/csd_bs.c | 477 | ||||
-rw-r--r-- | src/libmsc/csd_filter.c | 157 | ||||
-rw-r--r-- | src/libmsc/gsm_04_08_cc.c | 117 | ||||
-rw-r--r-- | src/libmsc/msc_a.c | 51 | ||||
-rw-r--r-- | src/libmsc/sdp_msg.c | 16 | ||||
-rw-r--r-- | src/libmsc/transaction_cc.c | 35 |
12 files changed, 913 insertions, 60 deletions
diff --git a/include/osmocom/msc/Makefile.am b/include/osmocom/msc/Makefile.am index 948021a0c..3286c3770 100644 --- a/include/osmocom/msc/Makefile.am +++ b/include/osmocom/msc/Makefile.am @@ -3,6 +3,8 @@ noinst_HEADERS = \ cell_id_list.h \ codec_filter.h \ codec_mapping.h \ + csd_bs.h \ + csd_filter.h \ db.h \ debug.h \ e_link.h \ diff --git a/include/osmocom/msc/csd_bs.h b/include/osmocom/msc/csd_bs.h new file mode 100644 index 000000000..eee869266 --- /dev/null +++ b/include/osmocom/msc/csd_bs.h @@ -0,0 +1,54 @@ +/* 3GPP TS 122.002 Bearer Services */ +#pragma once + +#include <osmocom/gsm/mncc.h> +#include <osmocom/gsm/protocol/gsm_08_08.h> + +enum csd_bs { + CSD_BS_NONE, + + /* 3.1.1.1.2 */ + CSD_BS_21_T_V110_0k3, + CSD_BS_22_T_V110_1k2, + CSD_BS_24_T_V110_2k4, + CSD_BS_25_T_V110_4k8, + CSD_BS_26_T_V110_9k6, + + /* 3.1.1.2.2 */ + CSD_BS_21_NT_V110_0k3, + CSD_BS_22_NT_V110_1k2, + CSD_BS_24_NT_V110_2k4, + CSD_BS_25_NT_V110_4k8, + CSD_BS_26_NT_V110_9k6, + + /* 3.1.2.1.2 */ + CSD_BS_31_T_V110_1k2, + CSD_BS_32_T_V110_2k4, + CSD_BS_33_T_V110_4k8, + CSD_BS_34_T_V110_9k6, + + CSD_BS_MAX, +}; + +struct csd_bs_list { + unsigned int count; + enum csd_bs bs[CSD_BS_MAX]; +}; + +void csd_bs_list_add_bs(struct csd_bs_list *list, enum csd_bs bs); +int csd_bs_list_to_bearer_cap(struct gsm_mncc_bearer_cap *cap, const struct csd_bs_list *list); +void csd_bs_list_from_bearer_cap(struct csd_bs_list *list, const struct gsm_mncc_bearer_cap *cap); + +int csd_bs_to_str_buf(char *buf, size_t buflen, enum csd_bs bs); +char *csd_bs_to_str_c(void *ctx, enum csd_bs bs); +const char *csd_bs_to_str(enum csd_bs bs); + +int csd_bs_list_to_str_buf(char *buf, size_t buflen, const struct csd_bs_list *list); +char *csd_bs_list_to_str_c(void *ctx, const struct csd_bs_list *list); +const char *csd_bs_list_to_str(const struct csd_bs_list *list); + +void csd_bs_list_add_bs(struct csd_bs_list *list, enum csd_bs bs); +void csd_bs_list_remove(struct csd_bs_list *list, enum csd_bs bs); +void csd_bs_list_intersection(struct csd_bs_list *dest, const struct csd_bs_list *other); + +int csd_bs_list_to_gsm0808_channel_type(struct gsm0808_channel_type *ct, const struct csd_bs_list *list); diff --git a/include/osmocom/msc/csd_filter.h b/include/osmocom/msc/csd_filter.h new file mode 100644 index 000000000..51ffff706 --- /dev/null +++ b/include/osmocom/msc/csd_filter.h @@ -0,0 +1,53 @@ +/* Filter/overlay data rates for CSD, across MS, RAN and CN limitations */ +/* + * (C) 2023 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de> + * All Rights Reserved + * + * Author: Oliver Smith + * + * SPDX-License-Identifier: GPL-2.0+ + * + * 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. + */ +#pragma once + +#include <osmocom/gsm/gsm_utils.h> +#include <osmocom/gsm/mncc.h> +#include <osmocom/mgcp_client/mgcp_client.h> + +#include <osmocom/msc/csd_bs.h> +#include <osmocom/msc/sdp_msg.h> + +/* Combine various data rate selections to obtain a resulting set allowed by + * all of them. Members reflect the different entities/stages that select data + * rates in CSD. Call csd_filter_run() and obtain the resulting set in + * csd_filter.result. */ +struct csd_filter { + /* The fixed set available on the RAN type, per definition. */ + struct csd_bs_list ran; + /* The services advertised by the MS Bearer Capabilities */ + struct csd_bs_list ms; + /* If known, the set the current RAN cell allows / has available. This + * may not be available if the BSC does not issue this information + * early enough. Should be ignored if empty. */ + struct csd_bs_list bss; + + /* After a channel was assigned, this reflects the chosen BS. */ + enum csd_bs assignment; +}; + +void csd_filter_set_ran(struct csd_filter *filter, enum osmo_rat_type ran_type); +int csd_filter_run(struct csd_filter *filter, struct sdp_msg *result, const struct sdp_msg *remote); + +int csd_filter_to_str_buf(char *buf, size_t buflen, const struct csd_filter *filter, + const struct sdp_msg *result, const struct sdp_msg *remote); +char *csd_filter_to_str_c(void *ctx, const struct csd_filter *filter, const struct sdp_msg *result, const struct sdp_msg *remote); +const char *csd_filter_to_str(const struct csd_filter *filter, const struct sdp_msg *result, const struct sdp_msg *remote); diff --git a/include/osmocom/msc/sdp_msg.h b/include/osmocom/msc/sdp_msg.h index 1b905b7ef..e62f22b0d 100644 --- a/include/osmocom/msc/sdp_msg.h +++ b/include/osmocom/msc/sdp_msg.h @@ -4,6 +4,8 @@ #include <osmocom/core/utils.h> #include <osmocom/core/sockaddr_str.h> +#include <osmocom/msc/csd_bs.h> + extern const struct value_string sdp_msg_payload_type_names[]; static inline const char *sdp_msg_payload_type_name(unsigned int payload_type) { return get_value_string(sdp_msg_payload_type_names, payload_type); } @@ -36,6 +38,7 @@ struct sdp_msg { unsigned int ptime; enum sdp_mode_e mode; struct sdp_audio_codecs audio_codecs; + struct csd_bs_list bearer_services; }; #define foreach_sdp_audio_codec(/* struct sdp_audio_codec* */ CODEC, \ @@ -80,3 +83,5 @@ const char *sdp_audio_codecs_to_str(const struct sdp_audio_codecs *ac); int sdp_msg_to_str_buf(char *buf, size_t buflen, const struct sdp_msg *sdp); char *sdp_msg_to_str_c(void *ctx, const struct sdp_msg *sdp); const char *sdp_msg_to_str(const struct sdp_msg *sdp); + +void sdp_audio_codecs_set_csd(struct sdp_audio_codecs *ac); diff --git a/include/osmocom/msc/transaction.h b/include/osmocom/msc/transaction.h index 36aab7874..d2a463deb 100644 --- a/include/osmocom/msc/transaction.h +++ b/include/osmocom/msc/transaction.h @@ -9,6 +9,7 @@ #include <osmocom/msc/msc_a.h> #include <osmocom/msc/debug.h> #include <osmocom/msc/codec_filter.h> +#include <osmocom/msc/csd_filter.h> #include <osmocom/gsm/gsm0411_smc.h> #include <osmocom/gsm/gsm0411_smr.h> @@ -107,8 +108,9 @@ struct gsm_trans { struct osmo_lcls *lcls; /* SDP as last received from the remote call leg. */ struct sdp_msg remote; - /* Track codec choices from BSS and remote call leg */ + /* Track codec/CSD choices from BSS and remote call leg */ struct codec_filter codecs; + struct csd_filter csd; /* Resulting choice from codecs/bearer services and the * local RTP address to be sent to the remote call leg. */ struct sdp_msg local; diff --git a/src/libmsc/Makefile.am b/src/libmsc/Makefile.am index 957747500..fba7b5354 100644 --- a/src/libmsc/Makefile.am +++ b/src/libmsc/Makefile.am @@ -29,6 +29,8 @@ libmsc_a_SOURCES = \ cell_id_list.c \ codec_filter.c \ codec_mapping.c \ + csd_bs.c \ + csd_filter.c \ sccp_ran.c \ msc_vty.c \ db.c \ diff --git a/src/libmsc/csd_bs.c b/src/libmsc/csd_bs.c new file mode 100644 index 000000000..adb92937b --- /dev/null +++ b/src/libmsc/csd_bs.c @@ -0,0 +1,477 @@ +/* 3GPP TS 122.002 Bearer Services */ +/* + * (C) 2023 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de> + * All Rights Reserved + * + * Author: Oliver Smith + * + * SPDX-License-Identifier: AGPL-3.0+ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU Affero General Public License as published by + * the Free Software Foundation; either version 3 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 Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +#include <errno.h> + +#include <osmocom/msc/csd_bs.h> +#include <osmocom/msc/debug.h> + +/* csd_bs related below */ + +struct csd_bs_map { + /* BS number (20, 21, ...) */ + unsigned int num; + /* Access Structure (1: asynchronous, 0: synchronous) */ + bool async; + /* QoS Attribute (1: transparent, 0: non-transparent) */ + bool transp; + /* Rate Adaption (V110, V120 etc.) */ + enum gsm48_bcap_ra ra; + /* Fixed Network User Rate */ + unsigned int rate; +}; + +static const struct csd_bs_map bs_map[] = { + /* 3.1.1.1.2 */ + [CSD_BS_21_T_V110_0k3] = { + .num = 21, + .async = true, + .transp = true, + .ra = GSM48_BCAP_RA_V110_X30, + .rate = 300, + }, + [CSD_BS_22_T_V110_1k2] = { + .num = 22, + .async = true, + .transp = true, + .ra = GSM48_BCAP_RA_V110_X30, + .rate = 1200, + }, + [CSD_BS_24_T_V110_2k4] = { + .num = 24, + .async = true, + .transp = true, + .ra = GSM48_BCAP_RA_V110_X30, + .rate = 2400, + }, + [CSD_BS_25_T_V110_4k8] = { + .num = 25, + .async = true, + .transp = true, + .ra = GSM48_BCAP_RA_V110_X30, + .rate = 4800, + }, + [CSD_BS_26_T_V110_9k6] = { + .num = 26, + .async = true, + .transp = true, + .ra = GSM48_BCAP_RA_V110_X30, + .rate = 9600, + }, + + /* 3.1.1.2.2 */ + [CSD_BS_21_NT_V110_0k3] = { + .num = 21, + .async = true, + .transp = false, + .ra = GSM48_BCAP_RA_V110_X30, + .rate = 300, + }, + [CSD_BS_22_NT_V110_1k2] = { + .num = 22, + .async = true, + .transp = false, + .ra = GSM48_BCAP_RA_V110_X30, + .rate = 1200, + }, + [CSD_BS_24_NT_V110_2k4] = { + .num = 24, + .async = true, + .transp = false, + .ra = GSM48_BCAP_RA_V110_X30, + .rate = 2400, + }, + [CSD_BS_25_NT_V110_4k8] = { + .num = 25, + .async = true, + .transp = false, + .ra = GSM48_BCAP_RA_V110_X30, + .rate = 4800, + }, + [CSD_BS_26_NT_V110_9k6] = { + .num = 26, + .async = true, + .transp = false, + .ra = GSM48_BCAP_RA_V110_X30, + .rate = 9600, + }, + + /* 3.1.2.1.2 */ + [CSD_BS_31_T_V110_1k2] = { + .num = 31, + .async = false, + .transp = true, + .ra = GSM48_BCAP_RA_V110_X30, + .rate = 1200, + }, + [CSD_BS_32_T_V110_2k4] = { + .num = 32, + .async = false, + .transp = true, + .ra = GSM48_BCAP_RA_V110_X30, + .rate = 2400, + }, + [CSD_BS_33_T_V110_4k8] = { + .num = 33, + .async = false, + .transp = true, + .ra = GSM48_BCAP_RA_V110_X30, + .rate = 4800, + }, + [CSD_BS_34_T_V110_9k6] = { + .num = 34, + .async = false, + .transp = true, + .ra = GSM48_BCAP_RA_V110_X30, + .rate = 9600, + }, +}; + +osmo_static_assert(ARRAY_SIZE(bs_map) == CSD_BS_MAX, _invalid_size_bs_map); + +bool csd_bs_is_transp(enum csd_bs bs) +{ + return bs_map[bs].transp; +} + +/* Short single-line representation, convenient for logging. + * Like "BS25NT" */ +int csd_bs_to_str_buf(char *buf, size_t buflen, enum csd_bs bs) +{ + struct osmo_strbuf sb = { .buf = buf, .len = buflen }; + const struct csd_bs_map *map = &bs_map[bs]; + + OSMO_STRBUF_PRINTF(sb, "BS%u%s", + map->num, + map->transp ? "T" : "NT"); + + if (map->ra != GSM48_BCAP_RA_V110_X30) + OSMO_STRBUF_PRINTF(sb, "-RA=%d", map->ra); + + return sb.chars_needed; +} + +char *csd_bs_to_str_c(void *ctx, enum csd_bs bs) +{ + OSMO_NAME_C_IMPL(ctx, 32, "csd_bs_to_str_c-ERROR", csd_bs_to_str_buf, bs) +} + +const char *csd_bs_to_str(enum csd_bs bs) +{ + return csd_bs_to_str_c(OTC_SELECT, bs); +} + +static int csd_bs_to_gsm0808_data_rate_transp(enum csd_bs bs) +{ + switch (bs_map[bs].rate) { + case 1200: + return GSM0808_DATA_RATE_TRANSP_1k2; + case 2400: + return GSM0808_DATA_RATE_TRANSP_2k4; + case 4800: + return GSM0808_DATA_RATE_TRANSP_4k8; + case 9600: + return GSM0808_DATA_RATE_TRANSP_9k6; + } + return -EINVAL; +} + +static int csd_bs_to_gsm0808_data_rate_non_transp(enum csd_bs bs) +{ + uint16_t rate = bs_map[bs].rate; + + if (rate < 6000) + return GSM0808_DATA_RATE_NON_TRANSP_6k0; + if (rate < 12000) + return GSM0808_DATA_RATE_NON_TRANSP_12k0; + + return -EINVAL; +} + +static int csd_bs_to_gsm0808_data_rate_non_transp_allowed(enum csd_bs bs) +{ + uint16_t rate = bs_map[bs].rate; + + if (rate < 6000) + return GSM0808_DATA_RATE_NON_TRANSP_ALLOWED_6k0; + if (rate < 12000) + return GSM0808_DATA_RATE_NON_TRANSP_ALLOWED_12k0; + + return -EINVAL; +} + +enum csd_bs csd_bs_from_bearer_cap(const struct gsm_mncc_bearer_cap *cap, bool transp) +{ + enum gsm48_bcap_ra ra = cap->data.rate_adaption; + enum gsm48_bcap_user_rate rate = cap->data.user_rate; + bool async = cap->data.async; + + if (ra == GSM48_BCAP_RA_V110_X30 && async && transp) { + switch (rate) { + case GSM48_BCAP_UR_300: + return CSD_BS_21_T_V110_0k3; + case GSM48_BCAP_UR_1200: + return CSD_BS_22_T_V110_1k2; + case GSM48_BCAP_UR_2400: + return CSD_BS_24_T_V110_2k4; + case GSM48_BCAP_UR_4800: + return CSD_BS_25_T_V110_4k8; + case GSM48_BCAP_UR_9600: + return CSD_BS_26_T_V110_9k6; + default: + return CSD_BS_NONE; + } + } + + if (ra == GSM48_BCAP_RA_V110_X30 && async && !transp) { + switch (rate) { + case GSM48_BCAP_UR_300: + return CSD_BS_21_NT_V110_0k3; + case GSM48_BCAP_UR_1200: + return CSD_BS_22_NT_V110_1k2; + case GSM48_BCAP_UR_2400: + return CSD_BS_24_NT_V110_2k4; + case GSM48_BCAP_UR_4800: + return CSD_BS_25_NT_V110_4k8; + case GSM48_BCAP_UR_9600: + return CSD_BS_26_NT_V110_9k6; + default: + return CSD_BS_NONE; + } + } + + if (ra == GSM48_BCAP_RA_V110_X30 && !async && transp) { + switch (rate) { + case GSM48_BCAP_UR_1200: + return CSD_BS_31_T_V110_1k2; + case GSM48_BCAP_UR_2400: + return CSD_BS_32_T_V110_2k4; + case GSM48_BCAP_UR_4800: + return CSD_BS_33_T_V110_4k8; + case GSM48_BCAP_UR_9600: + return CSD_BS_34_T_V110_9k6; + default: + return CSD_BS_NONE; + } + } + + return CSD_BS_NONE; +} + +/* csd_bs_list related below */ + +int csd_bs_list_to_str_buf(char *buf, size_t buflen, const struct csd_bs_list *list) +{ + struct osmo_strbuf sb = { .buf = buf, .len = buflen }; + int i; + + if (!list->count) + OSMO_STRBUF_PRINTF(sb, "(no-bearer-services)"); + + for (i = 0; i < list->count; i++) { + if (i) + OSMO_STRBUF_PRINTF(sb, ","); + + OSMO_STRBUF_APPEND(sb, csd_bs_to_str_buf, list->bs[i]); + } + return sb.chars_needed; +} + +char *csd_bs_list_to_str_c(void *ctx, const struct csd_bs_list *list) +{ + OSMO_NAME_C_IMPL(ctx, 128, "csd_bs_list_to_str_c-ERROR", csd_bs_list_to_str_buf, list) +} + +const char *csd_bs_list_to_str(const struct csd_bs_list *list) +{ + return csd_bs_list_to_str_c(OTC_SELECT, list); +} + +bool csd_bs_list_has_bs(const struct csd_bs_list *list, enum csd_bs bs) +{ + int i; + + for (i = 0; i < list->count; i++) { + if (list->bs[i] == bs) + return true; + } + + return false; +} + +void csd_bs_list_add_bs(struct csd_bs_list *list, enum csd_bs bs) +{ + int i; + + if (!bs) + return; + + for (i = 0; i < list->count; i++) { + if (list->bs[i] == bs) + return; + } + + list->bs[i] = bs; + list->count++; +} + +void csd_bs_list_remove(struct csd_bs_list *list, enum csd_bs bs) +{ + int i; + bool found = false; + + for (i = 0; i < list->count; i++) { + if (list->bs[i] == bs) { + found = true; + list->count--; + continue; + } + if (i && found) + list->bs[i-1] = list->bs[i]; + } +} + +void csd_bs_list_intersection(struct csd_bs_list *dest, const struct csd_bs_list *other) +{ + int i; + + for (i = 0; i < dest->count; i++) { + if (csd_bs_list_has_bs(other, dest->bs[i])) + continue; + csd_bs_list_remove(dest, dest->bs[i]); + i--; + } +} + +int csd_bs_list_to_gsm0808_channel_type(struct gsm0808_channel_type *ct, const struct csd_bs_list *list) +{ + int i; + int rc; + + *ct = (struct gsm0808_channel_type){ + .ch_indctr = GSM0808_CHAN_DATA, + }; + + OSMO_ASSERT(list->count); + + if (csd_bs_is_transp(list->bs[0])) { + ct->data_transparent = true; + ct->data_rate = csd_bs_to_gsm0808_data_rate_transp(list->bs[0]); + } else { + ct->data_rate = csd_bs_to_gsm0808_data_rate_non_transp(list->bs[0]); + } + + if (ct->data_rate < 0) + return -EINVAL; + + /* Other possible data rates allowed (3GPP TS 48.008 ยง 3.2.2.11, 5a) */ + if (!ct->data_transparent && list->count > 1) { + for (i = 1; i < list->count; i++) { + if (!csd_bs_is_transp(list->bs[i])) + continue; + + rc = csd_bs_to_gsm0808_data_rate_non_transp_allowed(list->bs[i]); + if (rc < 0) { + LOGP(DMSC, LOGL_DEBUG, "Failed to convert %s to allowed r i/f rate\n", + csd_bs_to_str(list->bs[i])); + continue; + } + + ct->data_rate_allowed |= rc; + } + if (ct->data_rate_allowed) + ct->data_rate_allowed_is_set = true; + } + + ct->ch_rate_type = GSM0808_SPEECH_FULL_BM; + + return 0; +} + +int csd_bs_list_to_bearer_cap(struct gsm_mncc_bearer_cap *cap, const struct csd_bs_list *list) +{ + *cap = (struct gsm_mncc_bearer_cap){ + .transfer = GSM_MNCC_BCAP_UNR_DIG, + }; + enum csd_bs bs; + int i; + + for (i = 0; i < list->count; i++) { + bs = list->bs[i]; + + cap->data.rate_adaption = GSM48_BCAP_RA_V110_X30; + cap->data.async = bs_map[bs].async; + cap->data.transp = bs_map[bs].transp; + + switch (bs_map[bs].rate) { + case 300: + cap->data.user_rate = GSM48_BCAP_UR_300; + break; + case 1200: + cap->data.user_rate = GSM48_BCAP_UR_1200; + break; + case 2400: + cap->data.user_rate = GSM48_BCAP_UR_2400; + break; + case 4800: + cap->data.user_rate = GSM48_BCAP_UR_4800; + break; + case 9600: + cap->data.user_rate = GSM48_BCAP_UR_9600; + break; + } + + /* FIXME: handle more than one list entry */ + return 1; + } + + return 0; +} + +void csd_bs_list_from_bearer_cap(struct csd_bs_list *list, const struct gsm_mncc_bearer_cap *cap) +{ + *list = (struct csd_bs_list){}; + + switch (cap->data.transp) { + case GSM48_BCAP_TR_TRANSP: + csd_bs_list_add_bs(list, csd_bs_from_bearer_cap(cap, true)); + break; + case GSM48_BCAP_TR_RLP: /* NT */ + csd_bs_list_add_bs(list, csd_bs_from_bearer_cap(cap, false)); + break; + case GSM48_BCAP_TR_TR_PREF: + csd_bs_list_add_bs(list, csd_bs_from_bearer_cap(cap, true)); + csd_bs_list_add_bs(list, csd_bs_from_bearer_cap(cap, false)); + break; + case GSM48_BCAP_TR_RLP_PREF: + csd_bs_list_add_bs(list, csd_bs_from_bearer_cap(cap, false)); + csd_bs_list_add_bs(list, csd_bs_from_bearer_cap(cap, true)); + break; + } + + if (!list->count) { + LOGP(DMSC, LOGL_ERROR, "Failed to get bearer service from bearer capabilities ra=%d, async=%d," + " transp=%d, user_rate=%d\n", cap->data.rate_adaption, cap->data.async, cap->data.transp, + cap->data.user_rate); + return; + } +} diff --git a/src/libmsc/csd_filter.c b/src/libmsc/csd_filter.c new file mode 100644 index 000000000..0f428cffe --- /dev/null +++ b/src/libmsc/csd_filter.c @@ -0,0 +1,157 @@ +/* Filter/overlay bearer service selections across MS, RAN and CN limitations */ +/* + * (C) 2023 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de> + * All Rights Reserved + * + * Author: Oliver Smith + * + * SPDX-License-Identifier: AGPL-3.0+ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU Affero General Public License as published by + * the Free Software Foundation; either version 3 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 Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <osmocom/mgcp_client/mgcp_client.h> + +#include <osmocom/msc/csd_filter.h> + +static void add_all_geran_bs(struct csd_bs_list *list) +{ + /* See 3GPP TS 122.002 Bearer Services */ + /* In order of preference. TODO: make configurable */ + + /* GSM-R */ + csd_bs_list_add_bs(list, CSD_BS_24_T_V110_2k4); + csd_bs_list_add_bs(list, CSD_BS_25_T_V110_4k8); + csd_bs_list_add_bs(list, CSD_BS_26_T_V110_9k6); + + /* Other */ + csd_bs_list_add_bs(list, CSD_BS_21_T_V110_0k3); + csd_bs_list_add_bs(list, CSD_BS_22_T_V110_1k2); + csd_bs_list_add_bs(list, CSD_BS_21_NT_V110_0k3); + csd_bs_list_add_bs(list, CSD_BS_22_NT_V110_1k2); + csd_bs_list_add_bs(list, CSD_BS_24_NT_V110_2k4); + csd_bs_list_add_bs(list, CSD_BS_25_NT_V110_4k8); + csd_bs_list_add_bs(list, CSD_BS_26_NT_V110_9k6); + csd_bs_list_add_bs(list, CSD_BS_31_T_V110_1k2); + csd_bs_list_add_bs(list, CSD_BS_32_T_V110_2k4); + csd_bs_list_add_bs(list, CSD_BS_33_T_V110_4k8); + csd_bs_list_add_bs(list, CSD_BS_34_T_V110_9k6); +} + +static void add_all_utran_bs(struct csd_bs_list *list) +{ + /* See 3GPP TS 122.002 Bearer Services */ + /* In order of preference. TODO: make configurable */ + csd_bs_list_add_bs(list, CSD_BS_21_NT_V110_0k3); + csd_bs_list_add_bs(list, CSD_BS_22_NT_V110_1k2); + csd_bs_list_add_bs(list, CSD_BS_24_NT_V110_2k4); + csd_bs_list_add_bs(list, CSD_BS_25_NT_V110_4k8); + csd_bs_list_add_bs(list, CSD_BS_26_NT_V110_9k6); +} + +void csd_filter_set_ran(struct csd_filter *filter, enum osmo_rat_type ran_type) +{ + filter->ran = (struct csd_bs_list){}; + + switch (ran_type) { + default: + case OSMO_RAT_GERAN_A: + add_all_geran_bs(&filter->ran); + break; + case OSMO_RAT_UTRAN_IU: + add_all_utran_bs(&filter->ran); + break; + } +} + +int csd_filter_run(struct csd_filter *filter, struct sdp_msg *result, const struct sdp_msg *remote) +{ + struct csd_bs_list *r = &result->bearer_services; + enum csd_bs a = filter->assignment; + + *r = filter->ran; + + if (filter->ms.count) + csd_bs_list_intersection(r, &filter->ms); + if (filter->bss.count) + csd_bs_list_intersection(r, &filter->bss); + if (remote->bearer_services.count) + csd_bs_list_intersection(r, &remote->bearer_services); + + /* Future: If osmo-msc were able to trigger a re-assignment [...] see + * comment in codec_filter_run(). */ + + if (a) { + *r = (struct csd_bs_list){}; + csd_bs_list_add_bs(r, a); + } + + result->audio_codecs.count = 1; + result->audio_codecs.codec[0] = (struct sdp_audio_codec){ + .payload_type = CODEC_CLEARMODE, + .subtype_name = "CLEARMODE", + .rate = 8000, + }; + + return 0; +} + + +int csd_filter_to_str_buf(char *buf, size_t buflen, const struct csd_filter *filter, + const struct sdp_msg *result, const struct sdp_msg *remote) +{ + struct osmo_strbuf sb = { .buf = buf, .len = buflen }; + OSMO_STRBUF_APPEND(sb, sdp_msg_to_str_buf, result); + OSMO_STRBUF_PRINTF(sb, " (from:"); + + if (filter->assignment) { + OSMO_STRBUF_PRINTF(sb, " assigned="); + OSMO_STRBUF_APPEND(sb, csd_bs_to_str_buf, filter->assignment); + } + + if (remote->bearer_services.count || osmo_sockaddr_str_is_nonzero(&remote->rtp)) { + OSMO_STRBUF_PRINTF(sb, " remote="); + OSMO_STRBUF_APPEND(sb, sdp_msg_to_str_buf, remote); + } + + if (filter->ms.count) { + OSMO_STRBUF_PRINTF(sb, " MS={"); + OSMO_STRBUF_APPEND(sb, csd_bs_list_to_str_buf, &filter->ms); + OSMO_STRBUF_PRINTF(sb, "}"); + } + + if (filter->bss.count) { + OSMO_STRBUF_PRINTF(sb, " bss={"); + OSMO_STRBUF_APPEND(sb, csd_bs_list_to_str_buf, &filter->bss); + OSMO_STRBUF_PRINTF(sb, "}"); + } + + OSMO_STRBUF_PRINTF(sb, " RAN={"); + OSMO_STRBUF_APPEND(sb, csd_bs_list_to_str_buf, &filter->ran); + OSMO_STRBUF_PRINTF(sb, "}"); + + OSMO_STRBUF_PRINTF(sb, ")"); + + return sb.chars_needed; +} + +char *csd_filter_to_str_c(void *ctx, const struct csd_filter *filter, const struct sdp_msg *result, const struct sdp_msg *remote) +{ + OSMO_NAME_C_IMPL(ctx, 128, "csd_filter_to_str_c-ERROR", csd_filter_to_str_buf, filter, result, remote) +} + +const char *csd_filter_to_str(const struct csd_filter *filter, const struct sdp_msg *result, const struct sdp_msg *remote) +{ + return csd_filter_to_str_c(OTC_SELECT, filter, result, remote); +} diff --git a/src/libmsc/gsm_04_08_cc.c b/src/libmsc/gsm_04_08_cc.c index 4bc87af6a..1d9942185 100644 --- a/src/libmsc/gsm_04_08_cc.c +++ b/src/libmsc/gsm_04_08_cc.c @@ -808,55 +808,86 @@ static int gsm48_cc_tx_setup(struct gsm_trans *trans, void *arg) trans_cc_filter_set_bss(trans, trans->msc_a); if (setup->fields & MNCC_F_BEARER_CAP) trans->bearer_cap.transfer = setup->bearer_cap.transfer; - /* sdp.remote: if SDP is included in the MNCC, take that as definitive list of remote audio codecs. */ - rx_mncc_sdp(trans, setup->msg_type, setup->sdp); - /* sdp.remote: if there is no SDP information or we failed to parse it, try using the Bearer Capability from - * MNCC, if any. */ - if (!trans->cc.remote.audio_codecs.count && (setup->fields & MNCC_F_BEARER_CAP)) { - trans->cc.remote = (struct sdp_msg){}; - trans_cc_set_remote_from_bc(trans, &setup->bearer_cap); - LOG_TRANS_CAT(trans, DMNCC, LOGL_DEBUG, "rx %s Bearer Cap: remote=%s\n", - get_mncc_name(setup->msg_type), sdp_msg_to_str(&trans->cc.remote)); - } - if (!trans->cc.remote.audio_codecs.count) - LOG_TRANS(trans, LOGL_INFO, - "Got no information of remote audio codecs: neither SDP nor Bearer Capability. Trying anyway.\n"); + + switch (trans->bearer_cap.transfer) { + case GSM48_BCAP_ITCAP_SPEECH: + /* sdp.remote: if SDP is included in the MNCC, take that as definitive list of remote audio codecs. */ + rx_mncc_sdp(trans, setup->msg_type, setup->sdp); + /* sdp.remote: if there is no SDP information or we failed to parse it, try using the Bearer Capability from + * MNCC, if any. */ + if (!trans->cc.remote.audio_codecs.count && (setup->fields & MNCC_F_BEARER_CAP)) { + trans->cc.remote = (struct sdp_msg){}; + trans_cc_set_remote_from_bc(trans, &setup->bearer_cap); + LOG_TRANS_CAT(trans, DMNCC, LOGL_DEBUG, "rx %s Bearer Cap: remote=%s\n", + get_mncc_name(setup->msg_type), sdp_msg_to_str(&trans->cc.remote)); + } + if (!trans->cc.remote.audio_codecs.count) + LOG_TRANS(trans, LOGL_INFO, + "Got no information of remote audio codecs: neither SDP nor Bearer Capability. Trying anyway.\n"); + break; + case GSM48_BCAP_ITCAP_UNR_DIG_INF: + sdp_audio_codecs_set_csd(&trans->cc.codecs.ms); + break; + default: + LOG_TRANS(trans, LOGL_ERROR, "Handling of information transfer capability %d not implemented\n", + trans->bearer_cap.transfer); + } trans_cc_filter_run(trans); - /* Compose Bearer Capability information that reflects only the codecs (Speech Versions) remaining after - * intersecting MS, BSS and remote call leg restrictions. To store in trans for later use, and to include in - * the outgoing CC Setup message. */ - bearer_cap = (struct gsm_mncc_bearer_cap){ - .speech_ver = { -1 }, - }; - sdp_audio_codecs_to_bearer_cap(&bearer_cap, &trans->cc.local.audio_codecs); - rc = bearer_cap_set_radio(&bearer_cap); - if (rc) { - LOG_TRANS(trans, LOGL_ERROR, "Error composing Bearer Capability for CC Setup\n"); - trans_free(trans); - msgb_free(msg); - return rc; + /* Compose Bearer Capability information that reflects only the codecs (Speech Versions) / CSD bearer services + * remaining after intersecting MS, BSS and remote call leg restrictions. To store in trans for later use, and + * to include in the outgoing CC Setup message. */ + switch (trans->bearer_cap.transfer) { + case GSM48_BCAP_ITCAP_SPEECH: + bearer_cap = (struct gsm_mncc_bearer_cap){ + .speech_ver = { -1 }, + }; + sdp_audio_codecs_to_bearer_cap(&bearer_cap, &trans->cc.local.audio_codecs); + rc = bearer_cap_set_radio(&bearer_cap); + if (rc) { + LOG_TRANS(trans, LOGL_ERROR, "Error composing Bearer Capability for CC Setup\n"); + trans_free(trans); + msgb_free(msg); + return rc; + } + /* If no resulting codecs remain, error out. We cannot find a codec that matches both call legs. If the MGW were + * able to transcode, we could use non-identical codecs on each conn of the MGW endpoint, but we are aiming for + * finding a matching codec. */ + if (bearer_cap.speech_ver[0] == -1) { + LOG_TRANS(trans, LOGL_ERROR, "%s: no codec match possible: %s\n", + get_mncc_name(setup->msg_type), + codec_filter_to_str(&trans->cc.codecs, &trans->cc.local, &trans->cc.remote)); + + /* incompatible codecs */ + rc = mncc_release_ind(trans->net, trans, trans->callref, + GSM48_CAUSE_LOC_PRN_S_LU, + GSM48_CC_CAUSE_INCOMPAT_DEST /* TODO: correct cause code? */); + trans->callref = 0; + trans_free(trans); + msgb_free(msg); + return rc; + } + break; + case GSM48_BCAP_ITCAP_UNR_DIG_INF: + if (csd_bs_list_to_bearer_cap(&bearer_cap, &trans->cc.local.bearer_services) == 0) { + LOG_TRANS(trans, LOGL_ERROR, "Error composing Bearer Capability for CC Setup\n"); + + /* incompatible codecs */ + rc = mncc_release_ind(trans->net, trans, trans->callref, + GSM48_CAUSE_LOC_PRN_S_LU, + GSM48_CC_CAUSE_INCOMPAT_DEST /* TODO: correct cause code? */); + trans->callref = 0; + trans_free(trans); + msgb_free(msg); + return rc; + } + break; } + /* Create a copy of the bearer capability in the transaction struct, so we can use this information later */ trans->bearer_cap = bearer_cap; - /* If no resulting codecs remain, error out. We cannot find a codec that matches both call legs. If the MGW were - * able to transcode, we could use non-identical codecs on each conn of the MGW endpoint, but we are aiming for - * finding a matching codec. */ - if (bearer_cap.speech_ver[0] == -1) { - LOG_TRANS(trans, LOGL_ERROR, "%s: no codec match possible: %s\n", - get_mncc_name(setup->msg_type), - codec_filter_to_str(&trans->cc.codecs, &trans->cc.local, &trans->cc.remote)); - - /* incompatible codecs */ - rc = mncc_release_ind(trans->net, trans, trans->callref, - GSM48_CAUSE_LOC_PRN_S_LU, - GSM48_CC_CAUSE_INCOMPAT_DEST /* TODO: correct cause code? */); - trans->callref = 0; - trans_free(trans); - msgb_free(msg); - return rc; - } + gsm48_encode_bearer_cap(msg, 0, &bearer_cap); /* facility */ diff --git a/src/libmsc/msc_a.c b/src/libmsc/msc_a.c index ca3820626..11b242e8b 100644 --- a/src/libmsc/msc_a.c +++ b/src/libmsc/msc_a.c @@ -640,23 +640,48 @@ static void msc_a_call_leg_ran_local_addr_available(struct msc_a *msc_a) trans_cc_filter_run(cc_trans); LOG_TRANS(cc_trans, LOGL_DEBUG, "Sending Assignment Command\n"); - if (!cc_trans->cc.local.audio_codecs.count) { - LOG_TRANS(cc_trans, LOGL_ERROR, "Assignment not possible, no matching codec: %s\n", - codec_filter_to_str(&cc_trans->cc.codecs, &cc_trans->cc.local, &cc_trans->cc.remote)); - call_leg_release(msc_a->cc.call_leg); - return; - } + switch (cc_trans->bearer_cap.transfer) { + case GSM48_BCAP_ITCAP_SPEECH: + if (!cc_trans->cc.local.audio_codecs.count) { + LOG_TRANS(cc_trans, LOGL_ERROR, "Assignment not possible, no matching codec: %s\n", + codec_filter_to_str(&cc_trans->cc.codecs, &cc_trans->cc.local, &cc_trans->cc.remote)); + call_leg_release(msc_a->cc.call_leg); + return; + } - /* Compose 48.008 Channel Type from the current set of codecs determined from both local and remote codec - * capabilities. */ - if (sdp_audio_codecs_to_gsm0808_channel_type(&channel_type, &cc_trans->cc.local.audio_codecs)) { - LOG_MSC_A(msc_a, LOGL_ERROR, "Cannot compose Channel Type (Permitted Speech) from codecs: %s\n", - codec_filter_to_str(&cc_trans->cc.codecs, &cc_trans->cc.local, &cc_trans->cc.remote)); - trans_free(cc_trans); + /* Compose 48.008 Channel Type from the current set of codecs + * determined from both local and remote codec capabilities. */ + if (sdp_audio_codecs_to_gsm0808_channel_type(&channel_type, &cc_trans->cc.local.audio_codecs)) { + LOG_MSC_A(msc_a, LOGL_ERROR, "Cannot compose Channel Type (Permitted Speech) from codecs: %s\n", + codec_filter_to_str(&cc_trans->cc.codecs, &cc_trans->cc.local, &cc_trans->cc.remote)); + trans_free(cc_trans); + return; + } + break; + case GSM48_BCAP_ITCAP_UNR_DIG_INF: + if (!cc_trans->cc.local.bearer_services.count) { + LOG_TRANS(cc_trans, LOGL_ERROR, "Assignment not possible, no matching bearer service: %s\n", + csd_filter_to_str(&cc_trans->cc.csd, &cc_trans->cc.local, &cc_trans->cc.remote)); + call_leg_release(msc_a->cc.call_leg); + return; + } + + /* Compose 48.008 Channel Type from the current set of bearer + * services determined from local and remote capabilities. */ + if (csd_bs_list_to_gsm0808_channel_type(&channel_type, &cc_trans->cc.local.bearer_services)) { + LOG_MSC_A(msc_a, LOGL_ERROR, "Cannot compose channel type from: %s\n", + csd_filter_to_str(&cc_trans->cc.csd, &cc_trans->cc.local, &cc_trans->cc.remote)); + return; + } + break; + default: + LOG_TRANS(cc_trans, LOGL_ERROR, "Assignment not possible for information transfer capability %d\n", + cc_trans->bearer_cap.transfer); + call_leg_release(msc_a->cc.call_leg); return; } - /* The RAN side RTP address is known, so the voice Assignment can commence. */ + /* The RAN side RTP address is known, so the voice/CSD Assignment can commence. */ msg = (struct ran_msg){ .msg_type = RAN_MSG_ASSIGNMENT_COMMAND, .assignment_command = { diff --git a/src/libmsc/sdp_msg.c b/src/libmsc/sdp_msg.c index d636222df..cd721d395 100644 --- a/src/libmsc/sdp_msg.c +++ b/src/libmsc/sdp_msg.c @@ -657,6 +657,10 @@ int sdp_msg_to_str_buf(char *buf, size_t buflen, const struct sdp_msg *sdp) OSMO_STRBUF_PRINTF(sb, OSMO_SOCKADDR_STR_FMT, OSMO_SOCKADDR_STR_FMT_ARGS(&sdp->rtp)); OSMO_STRBUF_PRINTF(sb, "{"); OSMO_STRBUF_APPEND(sb, sdp_audio_codecs_to_str_buf, &sdp->audio_codecs); + if (sdp->bearer_services.count) { + OSMO_STRBUF_PRINTF(sb, ","); + OSMO_STRBUF_APPEND(sb, csd_bs_list_to_str_buf, &sdp->bearer_services); + } OSMO_STRBUF_PRINTF(sb, "}"); return sb.chars_needed; } @@ -670,3 +674,15 @@ const char *sdp_msg_to_str(const struct sdp_msg *sdp) { return sdp_msg_to_str_c(OTC_SELECT, sdp); } + +void sdp_audio_codecs_set_csd(struct sdp_audio_codecs *ac) +{ + *ac = (struct sdp_audio_codecs){ + .count = 1, + .codec = {{ + .payload_type = 120, + .subtype_name = "CLEARMODE", + .rate = 8000, + }}, + }; +} diff --git a/src/libmsc/transaction_cc.c b/src/libmsc/transaction_cc.c index cb1424b63..35ec5dc86 100644 --- a/src/libmsc/transaction_cc.c +++ b/src/libmsc/transaction_cc.c @@ -24,32 +24,52 @@ #include <osmocom/msc/transaction_cc.h> #include <osmocom/msc/codec_filter.h> +#include <osmocom/msc/csd_filter.h> void trans_cc_filter_init(struct gsm_trans *trans) { trans->cc.codecs = (struct codec_filter){}; + trans->cc.csd = (struct csd_filter){}; } void trans_cc_filter_set_ran(struct gsm_trans *trans, enum osmo_rat_type ran_type) { codec_filter_set_ran(&trans->cc.codecs, ran_type); + csd_filter_set_ran(&trans->cc.csd, ran_type); } void trans_cc_filter_set_bss(struct gsm_trans *trans, struct msc_a *msc_a) { codec_filter_set_bss(&trans->cc.codecs, &msc_a->cc.compl_l3_codec_list_bss_supported); + + /* For CSD, there is no list of supported bearer services passed in + * Complete Layer 3. TODO: make it configurable? */ } void trans_cc_filter_run(struct gsm_trans *trans) { - codec_filter_run(&trans->cc.codecs, &trans->cc.local, &trans->cc.remote); - LOG_TRANS(trans, LOGL_DEBUG, "codecs: %s\n", - codec_filter_to_str(&trans->cc.codecs, &trans->cc.local, &trans->cc.remote)); + switch (trans->bearer_cap.transfer) { + case GSM48_BCAP_ITCAP_SPEECH: + codec_filter_run(&trans->cc.codecs, &trans->cc.local, &trans->cc.remote); + LOG_TRANS(trans, LOGL_DEBUG, "codecs: %s\n", + codec_filter_to_str(&trans->cc.codecs, &trans->cc.local, &trans->cc.remote)); + break; + case GSM48_BCAP_ITCAP_UNR_DIG_INF: + csd_filter_run(&trans->cc.csd, &trans->cc.local, &trans->cc.remote); + LOG_TRANS(trans, LOGL_DEBUG, "codec/BS: %s\n", + csd_filter_to_str(&trans->cc.csd, &trans->cc.local, &trans->cc.remote)); + break; + default: + LOG_TRANS(trans, LOGL_ERROR, "Handling of information transfer capability %d not implemented\n", + trans->bearer_cap.transfer); + break; + } } void trans_cc_filter_set_ms_from_bc(struct gsm_trans *trans, const struct gsm_mncc_bearer_cap *bcap) { trans->cc.codecs.ms = (struct sdp_audio_codecs){0}; + trans->cc.csd.ms = (struct csd_bs_list){0}; if (!bcap) return; @@ -58,6 +78,10 @@ void trans_cc_filter_set_ms_from_bc(struct gsm_trans *trans, const struct gsm_mn case GSM48_BCAP_ITCAP_SPEECH: sdp_audio_codecs_from_bearer_cap(&trans->cc.codecs.ms, bcap); break; + case GSM48_BCAP_ITCAP_UNR_DIG_INF: + sdp_audio_codecs_set_csd(&trans->cc.codecs.ms); + csd_bs_list_from_bearer_cap(&trans->cc.csd.ms, bcap); + break; default: LOG_TRANS(trans, LOGL_ERROR, "Handling of information transfer capability %d not implemented\n", bcap->transfer); @@ -68,6 +92,7 @@ void trans_cc_filter_set_ms_from_bc(struct gsm_trans *trans, const struct gsm_mn void trans_cc_set_remote_from_bc(struct gsm_trans *trans, const struct gsm_mncc_bearer_cap *bcap) { trans->cc.remote.audio_codecs = (struct sdp_audio_codecs){0}; + trans->cc.remote.bearer_services = (struct csd_bs_list){0}; if (!bcap) return; @@ -76,6 +101,10 @@ void trans_cc_set_remote_from_bc(struct gsm_trans *trans, const struct gsm_mncc_ case GSM48_BCAP_ITCAP_SPEECH: sdp_audio_codecs_from_bearer_cap(&trans->cc.remote.audio_codecs, bcap); break; + case GSM48_BCAP_ITCAP_UNR_DIG_INF: + sdp_audio_codecs_set_csd(&trans->cc.remote.audio_codecs); + csd_bs_list_from_bearer_cap(&trans->cc.remote.bearer_services, bcap); + break; default: LOG_TRANS(trans, LOGL_ERROR, "Handling of information transfer capability %d not implemented\n", bcap->transfer); |