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osmo-msc/src/libmsc/transaction.c

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7.3 KiB

/* 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>
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);
/*! 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 ran_conn *conn,
uint8_t proto, uint8_t trans_id)
{
struct gsm_trans *trans;
struct gsm_network *net = conn->network;
struct vlr_subscr *vsub = conn->vsub;
llist_for_each_entry(trans, &net->trans_list, entry) {
if (trans->vsub == vsub &&
trans->protocol == proto &&
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->protocol == GSM48_PDISC_SMS &&
trans->sms.sm_rp_mr == sm_rp_mr)
return trans;
}
return NULL;
}
static const char *trans_vsub_use(uint8_t proto)
{
return get_value_string_or_null(gsm48_pdisc_names, proto) ? : "trans-proto-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,
uint8_t protocol, uint8_t trans_id,
uint32_t callref)
{
struct gsm_trans *trans;
/* a valid subscriber is indispensable */
if (vsub == NULL) {
LOGP(DVLR, LOGL_ERROR,
"unable to alloc transaction, invalid subscriber (NULL)\n");
return NULL;
}
DEBUGP(DCC, "(ti %02x sub %s callref %x) New transaction\n",
trans_id, vlr_subscr_name(vsub), callref);
trans = talloc_zero(tall_trans_ctx, struct gsm_trans);
if (!trans)
return NULL;
vlr_subscr_get(vsub, trans_vsub_use(protocol));
trans->vsub = vsub;
trans->protocol = protocol;
trans->transaction_id = trans_id;
trans->callref = callref;
trans->net = net;
llist_add_tail(&trans->entry, &net->trans_list);
return trans;
}
/*! Release a transaction
* \param[in] trans Transaction to be released
*/
void trans_free(struct gsm_trans *trans)
{
enum ran_conn_use conn_usage_token;
struct ran_conn *conn;
switch (trans->protocol) {
case GSM48_PDISC_CC:
_gsm48_cc_trans_free(trans);
conn_usage_token = RAN_CONN_USE_TRANS_CC;
break;
case GSM48_PDISC_SMS:
_gsm411_sms_trans_free(trans);
conn_usage_token = RAN_CONN_USE_TRANS_SMS;
break;
case GSM48_PDISC_NC_SS:
_gsm911_nc_ss_trans_free(trans);
conn_usage_token = RAN_CONN_USE_TRANS_NC_SS;
break;
default:
conn_usage_token = RAN_CONN_USE_UNTRACKED;
break;
}
if (trans->paging_request) {
subscr_remove_request(trans->paging_request);
trans->paging_request = NULL;
}
if (trans->vsub) {
vlr_subscr_put(trans->vsub, trans_vsub_use(trans->protocol));
trans->vsub = NULL;
}
conn = trans->conn;
trans->conn = NULL;
llist_del(&trans->entry);
talloc_free(trans);
if (conn)
ran_conn_put(conn, conn_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,
uint8_t protocol)
{
struct gsm_trans *trans;
unsigned int used_tid_bitmask = 0;
int i, j, h;
/* generate bitmask of already-used TIDs for this (subscr,proto) */
llist_for_each_entry(trans, &net->trans_list, entry) {
if (trans->vsub != vsub ||
trans->protocol != protocol ||
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 ran_conn *conn)
{
struct gsm_trans *trans;
llist_for_each_entry(trans, &conn->network->trans_list, entry)
if (trans->conn == conn)
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 ran_conn *conn)
{
struct gsm_trans *trans;
/* 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.
*/
restart:
llist_for_each_entry(trans, &conn->network->trans_list, entry) {
if (trans->conn == conn) {
trans_free(trans);
goto restart;
}
}
}