From 03fd8d014f9871896a86534432c8757d65a576fe Mon Sep 17 00:00:00 2001 From: Jonathan Santos Date: Wed, 25 May 2011 13:54:02 -0400 Subject: Import upstream version 0.9.13 --- src/libbsc/bsc_api.c | 675 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 675 insertions(+) create mode 100644 src/libbsc/bsc_api.c (limited to 'src/libbsc/bsc_api.c') diff --git a/src/libbsc/bsc_api.c b/src/libbsc/bsc_api.c new file mode 100644 index 000000000..0f09aecd3 --- /dev/null +++ b/src/libbsc/bsc_api.c @@ -0,0 +1,675 @@ +/* GSM 08.08 like API for OpenBSC. The bridge from MSC to BSC */ + +/* (C) 2010 by Holger Hans Peter Freyther + * (C) 2010 by On-Waves + * (C) 2009 by Harald Welte + * + * All Rights Reserved + * + * 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 . + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#include + +#define GSM0808_T10_VALUE 6, 0 + +static LLIST_HEAD(sub_connections); + +static void rll_ind_cb(struct gsm_lchan *, uint8_t, void *, enum bsc_rllr_ind); +static void send_sapi_reject(struct gsm_subscriber_connection *conn, int link_id); +static void handle_release(struct gsm_subscriber_connection *conn, struct bsc_api *bsc, struct gsm_lchan *lchan); +static void handle_chan_ack(struct gsm_subscriber_connection *conn, struct bsc_api *bsc, struct gsm_lchan *lchan); +static void handle_chan_nack(struct gsm_subscriber_connection *conn, struct bsc_api *bsc, struct gsm_lchan *lchan); + +/* GSM 08.08 3.2.2.33 */ +static u_int8_t lchan_to_chosen_channel(struct gsm_lchan *lchan) +{ + u_int8_t channel_mode = 0, channel = 0; + + switch (lchan->tch_mode) { + case GSM48_CMODE_SPEECH_V1: + case GSM48_CMODE_SPEECH_EFR: + case GSM48_CMODE_SPEECH_AMR: + channel_mode = 0x9; + break; + case GSM48_CMODE_SIGN: + channel_mode = 0x8; + break; + case GSM48_CMODE_DATA_14k5: + channel_mode = 0xe; + break; + case GSM48_CMODE_DATA_12k0: + channel_mode = 0xb; + break; + case GSM48_CMODE_DATA_6k0: + channel_mode = 0xc; + break; + case GSM48_CMODE_DATA_3k6: + channel_mode = 0xd; + break; + } + + switch (lchan->type) { + case GSM_LCHAN_NONE: + channel = 0x0; + break; + case GSM_LCHAN_SDCCH: + channel = 0x1; + break; + case GSM_LCHAN_TCH_F: + channel = 0x8; + break; + case GSM_LCHAN_TCH_H: + channel = 0x9; + break; + case GSM_LCHAN_UNKNOWN: + LOGP(DMSC, LOGL_ERROR, "Unknown lchan type: %p\n", lchan); + break; + } + + return channel_mode << 4 | channel; +} + +static u_int8_t chan_mode_to_speech(struct gsm_lchan *lchan) +{ + int mode = 0; + + switch (lchan->tch_mode) { + case GSM48_CMODE_SPEECH_V1: + mode = 1; + break; + case GSM48_CMODE_SPEECH_EFR: + mode = 0x11; + break; + case GSM48_CMODE_SPEECH_AMR: + mode = 0x21; + break; + case GSM48_CMODE_SIGN: + case GSM48_CMODE_DATA_14k5: + case GSM48_CMODE_DATA_12k0: + case GSM48_CMODE_DATA_6k0: + case GSM48_CMODE_DATA_3k6: + default: + LOGP(DMSC, LOGL_ERROR, "Using non speech mode: %d\n", mode); + return 0; + break; + } + + /* assume to always do AMR HR on any TCH type */ + if (lchan->type == GSM_LCHAN_TCH_H || + lchan->tch_mode == GSM48_CMODE_SPEECH_AMR) + mode |= 0x4; + + return mode; +} + +static void assignment_t10_timeout(void *_conn) +{ + struct bsc_api *api; + struct gsm_subscriber_connection *conn = + (struct gsm_subscriber_connection *) _conn; + + LOGP(DMSC, LOGL_ERROR, "Assigment T10 timeout on %p\n", conn); + + /* normal release on the secondary channel */ + lchan_release(conn->secondary_lchan, 0, 1); + conn->secondary_lchan = NULL; + + /* inform them about the failure */ + api = conn->bts->network->bsc_api; + api->assign_fail(conn, GSM0808_CAUSE_NO_RADIO_RESOURCE_AVAILABLE, NULL); +} + +/* + * Start a new assignment and make sure that it is completed within T10 either + * positively, negatively or by the timeout. + * + * 1.) allocate a new lchan + * 2.) copy the encryption key and other data from the + * old to the new channel. + * 3.) RSL Channel Activate this channel and wait + * + * -> Signal handler for the LCHAN + * 4.) Send GSM 04.08 assignment command to the MS + * + * -> Assignment Complete/Assignment Failure + * 5.) Release the SDCCH, continue signalling on the new link + */ +static int handle_new_assignment(struct gsm_subscriber_connection *conn, int chan_mode, int full_rate) +{ + struct gsm_lchan *new_lchan; + int chan_type; + + chan_type = full_rate ? GSM_LCHAN_TCH_F : GSM_LCHAN_TCH_H; + + new_lchan = lchan_alloc(conn->bts, chan_type, 0); + + if (!new_lchan) { + LOGP(DMSC, LOGL_NOTICE, "No free channel.\n"); + return -1; + } + + /* copy old data to the new channel */ + memcpy(&new_lchan->encr, &conn->lchan->encr, sizeof(new_lchan->encr)); + new_lchan->ms_power = conn->lchan->ms_power; + new_lchan->bs_power = conn->lchan->bs_power; + + /* copy new data to it */ + new_lchan->tch_mode = chan_mode; + new_lchan->rsl_cmode = RSL_CMOD_SPD_SPEECH; + + /* handle AMR correctly */ + if (chan_mode == GSM48_CMODE_SPEECH_AMR) { + new_lchan->mr_conf.ver = 1; + new_lchan->mr_conf.icmi = 1; + new_lchan->mr_conf.m5_90 = 1; + } + + if (rsl_chan_activate_lchan(new_lchan, 0x1, 0, 0) < 0) { + LOGP(DHO, LOGL_ERROR, "could not activate channel\n"); + lchan_free(new_lchan); + return -1; + } + + /* remember that we have the channel */ + conn->secondary_lchan = new_lchan; + new_lchan->conn = conn; + + rsl_lchan_set_state(new_lchan, LCHAN_S_ACT_REQ); + return 0; +} + +struct gsm_subscriber_connection *subscr_con_allocate(struct gsm_lchan *lchan) +{ + struct gsm_subscriber_connection *conn; + + conn = talloc_zero(lchan->ts->trx->bts->network, struct gsm_subscriber_connection); + if (!conn) + return NULL; + + /* Configure the time and start it so it will be closed */ + conn->lchan = lchan; + conn->bts = lchan->ts->trx->bts; + lchan->conn = conn; + llist_add_tail(&conn->entry, &sub_connections); + return conn; +} + +/* TODO: move subscriber put here... */ +void subscr_con_free(struct gsm_subscriber_connection *conn) +{ + if (!conn) + return; + + + if (conn->subscr) { + subscr_put(conn->subscr); + conn->subscr = NULL; + } + + + if (conn->ho_lchan) { + LOGP(DNM, LOGL_ERROR, "The ho_lchan should have been cleared.\n"); + conn->ho_lchan->conn = NULL; + } + + if (conn->lchan) { + LOGP(DNM, LOGL_ERROR, "The lchan should have been cleared.\n"); + conn->lchan->conn = NULL; + } + + if (conn->secondary_lchan) { + LOGP(DNM, LOGL_ERROR, "The secondary_lchan should have been cleared.\n"); + conn->secondary_lchan->conn = NULL; + } + + llist_del(&conn->entry); + talloc_free(conn); +} + +int bsc_api_init(struct gsm_network *network, struct bsc_api *api) +{ + network->bsc_api = api; + return 0; +} + +int gsm0808_submit_dtap(struct gsm_subscriber_connection *conn, + struct msgb *msg, int link_id, int allow_sach) +{ + uint8_t sapi; + + + if (!conn->lchan) { + LOGP(DMSC, LOGL_ERROR, + "Called submit dtap without an lchan.\n"); + msgb_free(msg); + return -1; + } + + sapi = link_id & 0x7; + msg->lchan = conn->lchan; + msg->trx = msg->lchan->ts->trx; + + /* If we are on a TCH and need to submit a SMS (on SAPI=3) we need to use the SACH */ + if (allow_sach && sapi != 0) { + if (conn->lchan->type == GSM_LCHAN_TCH_F || conn->lchan->type == GSM_LCHAN_TCH_H) + link_id |= 0x40; + } + + msg->l3h = msg->data; + if (conn->lchan->sapis[sapi] == LCHAN_SAPI_UNUSED) { + OBSC_LINKID_CB(msg) = link_id; + if (rll_establish(msg->lchan, sapi, rll_ind_cb, msg) != 0) { + msgb_free(msg); + send_sapi_reject(conn, link_id); + return -1; + } + return 0; + } else { + return rsl_data_request(msg, link_id); + } +} + +/** + * Send a GSM08.08 Assignment Request. Right now this does not contain the + * audio codec type or the allowed rates for the config. It is assumed that + * this is for audio handling and that when we have a TCH it is capable of + * handling the audio codec. On top of that it is assumed that we are using + * AMR 5.9 when assigning a TCH/H. + */ +int gsm0808_assign_req(struct gsm_subscriber_connection *conn, int chan_mode, int full_rate) +{ + struct bsc_api *api; + api = conn->bts->network->bsc_api; + + if (conn->lchan->type == GSM_LCHAN_SDCCH) { + if (handle_new_assignment(conn, chan_mode, full_rate) != 0) + goto error; + } else { + LOGP(DMSC, LOGL_NOTICE, + "Sending ChanModify for speech %d %d\n", chan_mode, full_rate); + if (chan_mode == GSM48_CMODE_SPEECH_AMR) { + conn->lchan->mr_conf.ver = 1; + conn->lchan->mr_conf.icmi = 1; + conn->lchan->mr_conf.m5_90 = 1; + } + + gsm48_lchan_modify(conn->lchan, chan_mode); + } + + /* we will now start the timer to complete the assignment */ + conn->T10.cb = assignment_t10_timeout; + conn->T10.data = conn; + bsc_schedule_timer(&conn->T10, GSM0808_T10_VALUE); + return 0; + +error: + api->assign_fail(conn, 0, NULL); + return -1; +} + +int gsm0808_page(struct gsm_bts *bts, unsigned int page_group, unsigned int mi_len, + uint8_t *mi, int chan_type) +{ + return rsl_paging_cmd(bts, page_group, mi_len, mi, chan_type); +} + +static void handle_ass_compl(struct gsm_subscriber_connection *conn, + struct msgb *msg) +{ + struct gsm48_hdr *gh; + struct bsc_api *api = conn->bts->network->bsc_api; + + if (conn->secondary_lchan != msg->lchan) { + LOGP(DMSC, LOGL_ERROR, "Assignment Compl should occur on second lchan.\n"); + return; + } + + gh = msgb_l3(msg); + if (msgb_l3len(msg) - sizeof(*gh) != 1) { + LOGP(DMSC, LOGL_ERROR, "Assignment Compl invalid: %lu\n", + msgb_l3len(msg) - sizeof(*gh)); + return; + } + + /* swap channels */ + bsc_del_timer(&conn->T10); + + lchan_release(conn->lchan, 0, 1); + conn->lchan = conn->secondary_lchan; + conn->secondary_lchan = NULL; + + if (is_ipaccess_bts(conn->bts) && conn->lchan->tch_mode != GSM48_CMODE_SIGN) + rsl_ipacc_crcx(conn->lchan); + + api->assign_compl(conn, gh->data[0], + lchan_to_chosen_channel(conn->lchan), + conn->lchan->encr.alg_id, + chan_mode_to_speech(conn->lchan)); +} + +static void handle_ass_fail(struct gsm_subscriber_connection *conn, + struct msgb *msg) +{ + struct bsc_api *api = conn->bts->network->bsc_api; + uint8_t *rr_failure; + struct gsm48_hdr *gh; + + + if (conn->lchan != msg->lchan) { + LOGP(DMSC, LOGL_ERROR, "Assignment failure should occur on primary lchan.\n"); + return; + } + + /* stop the timer and release it */ + bsc_del_timer(&conn->T10); + lchan_release(conn->secondary_lchan, 0, 1); + conn->secondary_lchan = NULL; + + gh = msgb_l3(msg); + if (msgb_l3len(msg) - sizeof(*gh) != 1) { + LOGP(DMSC, LOGL_ERROR, "assignemnt failure unhandled: %lu\n", + msgb_l3len(msg) - sizeof(*gh)); + rr_failure = NULL; + } else { + rr_failure = &gh->data[0]; + } + + api->assign_fail(conn, + GSM0808_CAUSE_RADIO_INTERFACE_MESSAGE_FAILURE, + rr_failure); +} + +static void dispatch_dtap(struct gsm_subscriber_connection *conn, + uint8_t link_id, struct msgb *msg) +{ + struct bsc_api *api = msg->lchan->ts->trx->bts->network->bsc_api; + struct gsm48_hdr *gh; + uint8_t pdisc; + int rc; + + if (msgb_l3len(msg) < sizeof(*gh)) { + LOGP(DMSC, LOGL_ERROR, "Message too short for a GSM48 header.\n"); + return; + } + + gh = msgb_l3(msg); + pdisc = gh->proto_discr & 0x0f; + switch (pdisc) { + case GSM48_PDISC_RR: + switch (gh->msg_type) { + case GSM48_MT_RR_CIPH_M_COMPL: + if (api->cipher_mode_compl) + return api->cipher_mode_compl(conn, msg, + conn->lchan->encr.alg_id); + break; + case GSM48_MT_RR_ASS_COMPL: + handle_ass_compl(conn, msg); + break; + case GSM48_MT_RR_ASS_FAIL: + handle_ass_fail(conn, msg); + break; + case GSM48_MT_RR_CHAN_MODE_MODIF_ACK: + bsc_del_timer(&conn->T10); + rc = gsm48_rx_rr_modif_ack(msg); + if (rc < 0 && api->assign_fail) { + api->assign_fail(conn, + GSM0808_CAUSE_NO_RADIO_RESOURCE_AVAILABLE, + NULL); + } else if (rc >= 0 && api->assign_compl) + api->assign_compl(conn, 0, + lchan_to_chosen_channel(conn->lchan), + conn->lchan->encr.alg_id, + chan_mode_to_speech(conn->lchan)); + return; + break; + } + break; + case GSM48_PDISC_MM: + break; + } + + /* default case */ + if (api->dtap) + api->dtap(conn, link_id, msg); +} + +int gsm0408_rcvmsg(struct msgb *msg, uint8_t link_id) +{ + int rc; + struct bsc_api *api = msg->lchan->ts->trx->bts->network->bsc_api; + struct gsm_lchan *lchan; + + lchan = msg->lchan; + if (lchan->state != LCHAN_S_ACTIVE) { + LOGP(DRSL, LOGL_INFO, "Got data in non active state(%s), " + "discarding.\n", gsm_lchans_name(lchan->state)); + return -1; + } + + + if (lchan->conn) { + dispatch_dtap(lchan->conn, link_id, msg); + } else { + rc = BSC_API_CONN_POL_REJECT; + lchan->conn = subscr_con_allocate(msg->lchan); + if (!lchan->conn) { + lchan_release(lchan, 0, 0); + return -1; + } + + rc = api->compl_l3(lchan->conn, msg, 0); + + if (rc != BSC_API_CONN_POL_ACCEPT) { + lchan->conn->lchan = NULL; + subscr_con_free(lchan->conn); + lchan_release(lchan, 0, 0); + } + } + + return 0; +} + +int gsm0808_cipher_mode(struct gsm_subscriber_connection *conn, int cipher, + const uint8_t *key, int len, int include_imeisv) +{ + if (cipher > 0 && key == NULL) { + LOGP(DRSL, LOGL_ERROR, "Need to have an encrytpion key.\n"); + return -1; + } + + if (len > MAX_A5_KEY_LEN) { + LOGP(DRSL, LOGL_ERROR, "The key is too long: %d\n", len); + return -1; + } + + conn->lchan->encr.alg_id = RSL_ENC_ALG_A5(cipher); + if (key) { + conn->lchan->encr.key_len = len; + memcpy(conn->lchan->encr.key, key, len); + } + + return gsm48_send_rr_ciph_mode(conn->lchan, include_imeisv); +} + +/* + * Release all occupied RF Channels but stay around for more. + */ +int gsm0808_clear(struct gsm_subscriber_connection *conn) +{ + if (conn->ho_lchan) + bsc_clear_handover(conn, 1); + + if (conn->secondary_lchan) + lchan_release(conn->secondary_lchan, 0, 1); + + if (conn->lchan) + lchan_release(conn->lchan, 1, 0); + + conn->lchan = NULL; + conn->secondary_lchan = NULL; + conn->ho_lchan = NULL; + conn->bts = NULL; + + bsc_del_timer(&conn->T10); + + return 0; +} + +static void send_sapi_reject(struct gsm_subscriber_connection *conn, int link_id) +{ + struct bsc_api *api; + + if (!conn) + return; + + api = conn->bts->network->bsc_api; + if (!api || !api->sapi_n_reject) + return; + + api->sapi_n_reject(conn, link_id); +} + +static void rll_ind_cb(struct gsm_lchan *lchan, uint8_t link_id, void *_data, enum bsc_rllr_ind rllr_ind) +{ + struct msgb *msg = _data; + + /* + * There seems to be a small window that the RLL timer can + * fire after a lchan_release call and before the S_CHALLOC_FREED + * is called. Check if a conn is set before proceeding. + */ + if (!lchan->conn) + return; + + switch (rllr_ind) { + case BSC_RLLR_IND_EST_CONF: + rsl_data_request(msg, OBSC_LINKID_CB(msg)); + break; + case BSC_RLLR_IND_REL_IND: + case BSC_RLLR_IND_ERR_IND: + case BSC_RLLR_IND_TIMEOUT: + send_sapi_reject(lchan->conn, OBSC_LINKID_CB(msg)); + msgb_free(msg); + break; + } +} + +static int bsc_handle_lchan_signal(unsigned int subsys, unsigned int signal, + void *handler_data, void *signal_data) +{ + struct bsc_api *bsc; + struct gsm_lchan *lchan; + struct lchan_signal_data *lchan_data; + + if (subsys != SS_LCHAN) + return 0; + + + lchan_data = signal_data; + if (!lchan_data->lchan || !lchan_data->lchan->conn) + return 0; + + lchan = lchan_data->lchan; + bsc = lchan->ts->trx->bts->network->bsc_api; + if (!bsc) + return 0; + + switch (signal) { + case S_LCHAN_UNEXPECTED_RELEASE: + handle_release(lchan->conn, bsc, lchan); + break; + case S_LCHAN_ACTIVATE_ACK: + handle_chan_ack(lchan->conn, bsc, lchan); + break; + case S_LCHAN_ACTIVATE_NACK: + handle_chan_nack(lchan->conn, bsc, lchan); + break; + } + + return 0; +} + +static void handle_release(struct gsm_subscriber_connection *conn, + struct bsc_api *bsc, struct gsm_lchan *lchan) +{ + int destruct = 1; + + if (conn->secondary_lchan == lchan) { + bsc_del_timer(&conn->T10); + conn->secondary_lchan = NULL; + + bsc->assign_fail(conn, + GSM0808_CAUSE_RADIO_INTERFACE_FAILURE, + NULL); + } + + /* clear the connection now */ + if (bsc->clear_request) + destruct = bsc->clear_request(conn, 0); + + /* now give up all channels */ + if (conn->lchan == lchan) + conn->lchan = NULL; + if (conn->ho_lchan == lchan) { + bsc_clear_handover(conn, 0); + conn->ho_lchan = NULL; + } + lchan->conn = NULL; + + gsm0808_clear(conn); + + if (destruct) + subscr_con_free(conn); +} + +static void handle_chan_ack(struct gsm_subscriber_connection *conn, + struct bsc_api *api, struct gsm_lchan *lchan) +{ + if (conn->secondary_lchan != lchan) + return; + + LOGP(DMSC, LOGL_NOTICE, "Sending assignment on chan: %p\n", lchan); + gsm48_send_rr_ass_cmd(conn->lchan, lchan, 0x3); +} + +static void handle_chan_nack(struct gsm_subscriber_connection *conn, + struct bsc_api *api, struct gsm_lchan *lchan) +{ + if (conn->secondary_lchan != lchan) + return; + + LOGP(DMSC, LOGL_ERROR, "Channel activation failed. Waiting for timeout now\n"); + conn->secondary_lchan->conn = NULL; + conn->secondary_lchan = NULL; +} + +static __attribute__((constructor)) void on_dso_load_bsc(void) +{ + register_signal_handler(SS_LCHAN, bsc_handle_lchan_signal, NULL); +} -- cgit v1.2.3