| /* GSM 04.07 Transaction handling */ |
| |
| /* (C) 2009 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 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/msc/transaction.h> |
| #include <osmocom/msc/gsm_data.h> |
| #include <osmocom/msc/mncc.h> |
| #include <osmocom/msc/debug.h> |
| #include <osmocom/core/talloc.h> |
| #include <osmocom/msc/gsm_04_08.h> |
| #include <osmocom/msc/vlr.h> |
| #include <osmocom/msc/msc_a.h> |
| #include <osmocom/msc/msub.h> |
| #include <osmocom/msc/paging.h> |
| #include <osmocom/msc/silent_call.h> |
| |
| void *tall_trans_ctx; |
| |
| void _gsm48_cc_trans_free(struct gsm_trans *trans); |
| void _gsm411_sms_trans_free(struct gsm_trans *trans); |
| void _gsm911_nc_ss_trans_free(struct gsm_trans *trans); |
| |
| struct gsm_trans *trans_find_by_type(const struct msc_a *msc_a, enum trans_type type) |
| { |
| struct gsm_trans *trans; |
| struct gsm_network *net = msc_a_net(msc_a); |
| struct vlr_subscr *vsub = msc_a_vsub(msc_a); |
| |
| llist_for_each_entry(trans, &net->trans_list, entry) { |
| if (trans->vsub == vsub && trans->type == type) |
| return trans; |
| } |
| return NULL; |
| } |
| |
| /*! Find a transaction in connection for given protocol + transaction ID |
| * \param[in] conn Connection in which we want to find transaction |
| * \param[in] proto Protocol of transaction |
| * \param[in] trans_id Transaction ID of transaction |
| * \returns Matching transaction, if any |
| */ |
| struct gsm_trans *trans_find_by_id(const struct msc_a *msc_a, |
| enum trans_type type, uint8_t trans_id) |
| { |
| struct gsm_trans *trans; |
| struct gsm_network *net = msc_a_net(msc_a); |
| struct vlr_subscr *vsub = msc_a_vsub(msc_a); |
| |
| llist_for_each_entry(trans, &net->trans_list, entry) { |
| if (trans->vsub == vsub && |
| trans->type == type && |
| trans->transaction_id == trans_id) |
| return trans; |
| } |
| return NULL; |
| } |
| |
| /*! Find a transaction by call reference |
| * \param[in] net Network in which we should search |
| * \param[in] callref Call Reference of transaction |
| * \returns Matching transaction, if any |
| */ |
| struct gsm_trans *trans_find_by_callref(const struct gsm_network *net, |
| uint32_t callref) |
| { |
| struct gsm_trans *trans; |
| |
| llist_for_each_entry(trans, &net->trans_list, entry) { |
| if (trans->callref == callref) |
| return trans; |
| } |
| return NULL; |
| } |
| |
| /*! Find a transaction by SM-RP-MR (RP Message Reference) |
| * \param[in] net Network in which we should search |
| * \param[in] vsub Subscriber for which we should search |
| * \param[in] sm_rp_mr RP Message Reference (see GSM TS 04.11, section 8.2.3) |
| * \returns Matching transaction, NULL otherwise |
| */ |
| struct gsm_trans *trans_find_by_sm_rp_mr(const struct gsm_network *net, |
| const struct vlr_subscr *vsub, |
| uint8_t sm_rp_mr) |
| { |
| struct gsm_trans *trans; |
| |
| llist_for_each_entry(trans, &net->trans_list, entry) { |
| if (trans->vsub == vsub && |
| trans->type == TRANS_SMS && |
| trans->sms.sm_rp_mr == sm_rp_mr) |
| return trans; |
| } |
| |
| return NULL; |
| } |
| |
| static const char *trans_vsub_use(enum trans_type type) |
| { |
| return get_value_string_or_null(trans_type_names, type) ? : "trans-type-unknown"; |
| } |
| |
| /*! Allocate a new transaction and add it to network list |
| * \param[in] net Netwokr in which we allocate transaction |
| * \param[in] subscr Subscriber for which we allocate transaction |
| * \param[in] protocol Protocol (CC/SMS/...) |
| * \param[in] callref Call Reference |
| * \returns Transaction |
| */ |
| struct gsm_trans *trans_alloc(struct gsm_network *net, |
| struct vlr_subscr *vsub, |
| enum trans_type type, uint8_t trans_id, |
| uint32_t callref) |
| { |
| int subsys = trans_log_subsys(type); |
| struct gsm_trans *trans; |
| |
| /* a valid subscriber is indispensable */ |
| if (vsub == NULL) { |
| LOGP(subsys, LOGL_ERROR, "unable to alloc transaction, invalid subscriber (NULL)\n"); |
| return NULL; |
| } |
| |
| trans = talloc(tall_trans_ctx, struct gsm_trans); |
| if (!trans) |
| return NULL; |
| |
| *trans = (struct gsm_trans){ |
| .vsub = vsub, |
| .type = type, |
| .log_subsys = subsys, |
| .transaction_id = trans_id, |
| .callref = callref, |
| .net = net, |
| }; |
| vlr_subscr_get(vsub, trans_vsub_use(type)); |
| llist_add_tail(&trans->entry, &net->trans_list); |
| |
| LOG_TRANS(trans, LOGL_DEBUG, "New transaction\n"); |
| return trans; |
| } |
| |
| /*! Release a transaction |
| * \param[in] trans Transaction to be released |
| */ |
| void trans_free(struct gsm_trans *trans) |
| { |
| const char *usage_token; |
| struct msc_a *msc_a; |
| |
| LOG_TRANS(trans, LOGL_DEBUG, "Freeing transaction\n"); |
| |
| switch (trans->type) { |
| case TRANS_CC: |
| _gsm48_cc_trans_free(trans); |
| usage_token = MSC_A_USE_CC; |
| break; |
| case TRANS_SMS: |
| _gsm411_sms_trans_free(trans); |
| usage_token = MSC_A_USE_SMS; |
| break; |
| case TRANS_USSD: |
| _gsm911_nc_ss_trans_free(trans); |
| usage_token = MSC_A_USE_NC_SS; |
| break; |
| case TRANS_SILENT_CALL: |
| trans_silent_call_free(trans); |
| usage_token = MSC_A_USE_SILENT_CALL; |
| break; |
| default: |
| usage_token = NULL; |
| break; |
| } |
| |
| if (trans->paging_request) { |
| paging_request_remove(trans->paging_request); |
| trans->paging_request = NULL; |
| } |
| |
| if (trans->vsub) { |
| vlr_subscr_put(trans->vsub, trans_vsub_use(trans->type)); |
| trans->vsub = NULL; |
| } |
| |
| msc_a = trans->msc_a; |
| trans->msc_a = NULL; |
| |
| llist_del(&trans->entry); |
| talloc_free(trans); |
| |
| if (msc_a && usage_token) |
| msc_a_put(msc_a, usage_token); |
| } |
| |
| /*! allocate an unused transaction ID for the given subscriber |
| * in the given protocol using TI flag = 0 (allocated by us). |
| * See GSM 04.07, section 11.2.3.1.3 "Transaction identifier". |
| * \param[in] net GSM network |
| * \param[in] subscr Subscriber for which to assign a new TID |
| * \param[in] protocol Protocol of to be assigned TID |
| */ |
| int trans_assign_trans_id(const struct gsm_network *net, const struct vlr_subscr *vsub, |
| enum trans_type type) |
| { |
| struct gsm_trans *trans; |
| unsigned int used_tid_bitmask = 0; |
| int i, j, h; |
| uint8_t proto = trans_type_to_gsm48_proto(type); |
| |
| /* generate bitmask of already-used TIDs for this (subscr,proto) */ |
| llist_for_each_entry(trans, &net->trans_list, entry) { |
| if (trans->vsub != vsub || |
| proto != trans_type_to_gsm48_proto(trans->type) || |
| trans->transaction_id == TRANS_ID_UNASSIGNED) |
| continue; |
| used_tid_bitmask |= (1 << trans->transaction_id); |
| } |
| |
| /* find a new one, trying to go in a 'circular' pattern */ |
| for (h = 6; h > 0; h--) |
| if (used_tid_bitmask & (1 << h)) |
| break; |
| for (i = 0; i < 7; i++) { |
| j = (h + i) % 7; |
| if ((used_tid_bitmask & (1 << j)) == 0) |
| return j; |
| } |
| |
| return -1; |
| } |
| |
| /*! Check if we have any transaction for given connection |
| * \param[in] conn Connection to check |
| * \returns transaction pointer if found, NULL otherwise |
| */ |
| struct gsm_trans *trans_has_conn(const struct msc_a *msc_a) |
| { |
| struct gsm_trans *trans; |
| struct gsm_network *net = msc_a_net(msc_a); |
| |
| llist_for_each_entry(trans, &net->trans_list, entry) |
| if (trans->msc_a == msc_a) |
| return trans; |
| |
| return NULL; |
| } |
| |
| /*! Free all transactions associated with a connection, presumably when the |
| * conn is being closed. The transaction code will inform the CC or SMS |
| * facilities, which will then send the necessary release indications. |
| * \param[in] conn Connection that is going to be closed. |
| */ |
| void trans_conn_closed(const struct msc_a *msc_a) |
| { |
| /* As part of the CC REL_IND the remote leg might be released and this |
| * will trigger another call to trans_free. This is something the llist |
| * macro can not handle and we need to re-iterate the list every time. |
| */ |
| struct gsm_trans *trans; |
| while ((trans = trans_has_conn(msc_a))) |
| trans_free(trans); |
| } |
| |
| const struct value_string trans_type_names[] = { |
| { TRANS_CC, "CC" }, |
| { TRANS_SMS, "SMS" }, |
| { TRANS_USSD, "NCSS" }, |
| { TRANS_SILENT_CALL, "silent-call" }, |
| {} |
| }; |
| |
| uint8_t trans_type_to_gsm48_proto(enum trans_type type) |
| { |
| switch (type) { |
| case TRANS_CC: |
| case TRANS_SILENT_CALL: |
| return GSM48_PDISC_CC; |
| case TRANS_SMS: |
| return GSM48_PDISC_SMS; |
| case TRANS_USSD: |
| return GSM48_PDISC_NC_SS; |
| default: |
| return GSM48_PDISC_TEST; |
| } |
| |
| } |