sig_ss7.c

/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2010 Digium, Inc.
 *
 * Richard Mudgett <rmudgett@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*!
 * \file
 * \brief SS7 signaling module.
 *
 * \author Matthew Fredrickson <creslin@digium.com>
 * \author Richard Mudgett <rmudgett@digium.com>
 *
 * See Also:
 * \arg \ref AstCREDITS
 */

/*** MODULEINFO
	<support_level>core</support_level>
 ***/

#include "asterisk.h"

#if defined(HAVE_SS7)

#include <signal.h>

#include "asterisk/pbx.h"
#include "asterisk/causes.h"
#include "asterisk/musiconhold.h"
#include "asterisk/cli.h"
#include "asterisk/callerid.h"
#include "asterisk/transcap.h"
#include "asterisk/stasis_channels.h"

#include "sig_ss7.h"
#if !defined(LIBSS7_ABI_COMPATIBILITY)
#error "Upgrade your libss7"
#elif LIBSS7_ABI_COMPATIBILITY != 2
#error "Your installed libss7 is not compatible"
#endif

/* ------------------------------------------------------------------- */

static const char *sig_ss7_call_level2str(enum sig_ss7_call_level level)
{
	switch (level) {
	case SIG_SS7_CALL_LEVEL_IDLE:
		return "Idle";
	case SIG_SS7_CALL_LEVEL_ALLOCATED:
		return "Allocated";
	case SIG_SS7_CALL_LEVEL_CONTINUITY:
		return "Continuity";
	case SIG_SS7_CALL_LEVEL_SETUP:
		return "Setup";
	case SIG_SS7_CALL_LEVEL_PROCEEDING:
		return "Proceeding";
	case SIG_SS7_CALL_LEVEL_ALERTING:
		return "Alerting";
	case SIG_SS7_CALL_LEVEL_CONNECT:
		return "Connect";
	}
	return "Unknown";
}

static void sig_ss7_unlock_private(struct sig_ss7_chan *p)
{
	if (sig_ss7_callbacks.unlock_private) {
		sig_ss7_callbacks.unlock_private(p->chan_pvt);
	}
}

static void sig_ss7_lock_private(struct sig_ss7_chan *p)
{
	if (sig_ss7_callbacks.lock_private) {
		sig_ss7_callbacks.lock_private(p->chan_pvt);
	}
}

static void sig_ss7_deadlock_avoidance_private(struct sig_ss7_chan *p)
{
	if (sig_ss7_callbacks.deadlock_avoidance_private) {
		sig_ss7_callbacks.deadlock_avoidance_private(p->chan_pvt);
	} else {
		/* Fallback to the old way if callback not present. */
		sig_ss7_unlock_private(p);
		sched_yield();
		sig_ss7_lock_private(p);
	}
}

void sig_ss7_set_alarm(struct sig_ss7_chan *p, int in_alarm)
{
	p->inalarm = in_alarm;
	if (sig_ss7_callbacks.set_alarm) {
		sig_ss7_callbacks.set_alarm(p->chan_pvt, in_alarm);
	}
}

static void sig_ss7_set_dialing(struct sig_ss7_chan *p, int is_dialing)
{
	if (sig_ss7_callbacks.set_dialing) {
		sig_ss7_callbacks.set_dialing(p->chan_pvt, is_dialing);
	}
}

static void sig_ss7_set_digital(struct sig_ss7_chan *p, int is_digital)
{
	if (sig_ss7_callbacks.set_digital) {
		sig_ss7_callbacks.set_digital(p->chan_pvt, is_digital);
	}
}

static void sig_ss7_set_outgoing(struct sig_ss7_chan *p, int is_outgoing)
{
	p->outgoing = is_outgoing;
	if (sig_ss7_callbacks.set_outgoing) {
		sig_ss7_callbacks.set_outgoing(p->chan_pvt, is_outgoing);
	}
}

static void sig_ss7_set_inservice(struct sig_ss7_chan *p, int is_inservice)
{
	p->inservice = is_inservice;
	if (sig_ss7_callbacks.set_inservice) {
		sig_ss7_callbacks.set_inservice(p->chan_pvt, is_inservice);
	}
}

static void sig_ss7_set_locallyblocked(struct sig_ss7_chan *p, int is_blocked, int type)
{
	if (is_blocked) {
		p->locallyblocked |= type;
	} else {
		p->locallyblocked &= ~type;
	}

	if (sig_ss7_callbacks.set_locallyblocked) {
		sig_ss7_callbacks.set_locallyblocked(p->chan_pvt, p->locallyblocked);
	}
}

static void sig_ss7_set_remotelyblocked(struct sig_ss7_chan *p, int is_blocked, int type)
{
	if (is_blocked) {
		p->remotelyblocked |= type;
	} else {
		p->remotelyblocked &= ~type;
	}

	if (sig_ss7_callbacks.set_remotelyblocked) {
		sig_ss7_callbacks.set_remotelyblocked(p->chan_pvt, p->remotelyblocked);
	}
}

/*!
 * \internal
 * \brief Open the SS7 channel media path.
 * \since 1.8.12
 *
 * \param p Channel private control structure.
 *
 * \return Nothing
 */
static void sig_ss7_open_media(struct sig_ss7_chan *p)
{
	if (sig_ss7_callbacks.open_media) {
		sig_ss7_callbacks.open_media(p->chan_pvt);
	}
}

/*!
 * \internal
 * \brief Set the caller id information in the parent module.
 * \since 1.8
 *
 * \param p sig_ss7 channel structure.
 *
 * \return Nothing
 */
static void sig_ss7_set_caller_id(struct sig_ss7_chan *p)
{
	struct ast_party_caller caller;

	if (sig_ss7_callbacks.set_callerid) {
		ast_party_caller_init(&caller);

		caller.id.name.str = p->cid_name;
		caller.id.name.presentation = p->callingpres;
		caller.id.name.valid = 1;

		caller.id.number.str = p->cid_num;
		caller.id.number.plan = p->cid_ton;
		caller.id.number.presentation = p->callingpres;
		caller.id.number.valid = 1;

		if (!ast_strlen_zero(p->cid_subaddr)) {
			caller.id.subaddress.valid = 1;
			//caller.id.subaddress.type = 0;/* nsap */
			//caller.id.subaddress.odd_even_indicator = 0;
			caller.id.subaddress.str = p->cid_subaddr;
		}

		caller.ani.number.str = p->cid_ani;
		//caller.ani.number.plan = p->xxx;
		//caller.ani.number.presentation = p->xxx;
		caller.ani.number.valid = 1;

		caller.ani2 = p->cid_ani2;
		sig_ss7_callbacks.set_callerid(p->chan_pvt, &caller);
	}
}

/*!
 * \internal
 * \brief Set the Dialed Number Identifier.
 * \since 1.8
 *
 * \param p sig_ss7 channel structure.
 * \param dnid Dialed Number Identifier string.
 *
 * \return Nothing
 */
static void sig_ss7_set_dnid(struct sig_ss7_chan *p, const char *dnid)
{
	if (sig_ss7_callbacks.set_dnid) {
		sig_ss7_callbacks.set_dnid(p->chan_pvt, dnid);
	}
}

static int sig_ss7_play_tone(struct sig_ss7_chan *p, enum sig_ss7_tone tone)
{
	int res;

	if (sig_ss7_callbacks.play_tone) {
		res = sig_ss7_callbacks.play_tone(p->chan_pvt, tone);
	} else {
		res = -1;
	}
	return res;
}

static int sig_ss7_set_echocanceller(struct sig_ss7_chan *p, int enable)
{
	if (sig_ss7_callbacks.set_echocanceller) {
		return sig_ss7_callbacks.set_echocanceller(p->chan_pvt, enable);
	}
	return -1;
}

static void sig_ss7_loopback(struct sig_ss7_chan *p, int enable)
{
	if (p->loopedback != enable) {
		p->loopedback = enable;
		if (sig_ss7_callbacks.set_loopback) {
			sig_ss7_callbacks.set_loopback(p->chan_pvt, enable);
		}
	}
}

static struct ast_channel *sig_ss7_new_ast_channel(struct sig_ss7_chan *p, int state,
	int ulaw, int transfercapability, char *exten,
	const struct ast_assigned_ids *assignedids, const struct ast_channel *requestor)
{
	struct ast_channel *ast;

	if (sig_ss7_callbacks.new_ast_channel) {
		ast = sig_ss7_callbacks.new_ast_channel(p->chan_pvt, state, ulaw, exten,
			assignedids, requestor);
	} else {
		return NULL;
	}
	if (!ast) {
		return NULL;
	}

	if (!p->owner) {
		p->owner = ast;
	}

	if (p->outgoing) {
		p->do_hangup = SS7_HANGUP_FREE_CALL;
	} else {
		p->do_hangup = SS7_HANGUP_SEND_REL;
	}

	ast_channel_transfercapability_set(ast, transfercapability);
	pbx_builtin_setvar_helper(ast, "TRANSFERCAPABILITY",
		ast_transfercapability2str(transfercapability));
	if (transfercapability & AST_TRANS_CAP_DIGITAL) {
		sig_ss7_set_digital(p, 1);
	}

	return ast;
}

static void sig_ss7_handle_link_exception(struct sig_ss7_linkset *linkset, int which)
{
	if (sig_ss7_callbacks.handle_link_exception) {
		sig_ss7_callbacks.handle_link_exception(linkset, which);
	}
}

static struct sig_ss7_linkset *sig_ss7_find_linkset(struct ss7 *ss7)
{
	if (sig_ss7_callbacks.find_linkset) {
		return sig_ss7_callbacks.find_linkset(ss7);
	}
	return NULL;
}

/*!
 * \internal
 * \brief Determine if a private channel structure is available.
 *
 * \param pvt Channel to determine if available.
 *
 * \return TRUE if the channel is available.
 */
static int sig_ss7_is_chan_available(struct sig_ss7_chan *pvt)
{
	if (pvt->inservice && !pvt->inalarm && !pvt->owner && !pvt->ss7call
		&& pvt->call_level == SIG_SS7_CALL_LEVEL_IDLE
		&& !pvt->locallyblocked && !pvt->remotelyblocked) {
		return 1;
	}
	return 0;
}

/*!
 * \internal
 * \brief Obtain the sig_ss7 owner channel lock if the owner exists.
 * \since 1.8
 *
 * \param ss7 SS7 linkset control structure.
 * \param chanpos Channel position in the span.
 *
 * \note Assumes the ss7->lock is already obtained.
 * \note Assumes the sig_ss7_lock_private(ss7->pvts[chanpos]) is already obtained.
 *
 * \return Nothing
 */
static void sig_ss7_lock_owner(struct sig_ss7_linkset *ss7, int chanpos)
{
	for (;;) {
		if (!ss7->pvts[chanpos]->owner) {
			/* There is no owner lock to get. */
			break;
		}
		if (!ast_channel_trylock(ss7->pvts[chanpos]->owner)) {
			/* We got the lock */
			break;
		}

		/* Avoid deadlock */
		sig_ss7_unlock_private(ss7->pvts[chanpos]);
		DEADLOCK_AVOIDANCE(&ss7->lock);
		sig_ss7_lock_private(ss7->pvts[chanpos]);
	}
}

/*!
 * \internal
 * \brief Queue the given frame onto the owner channel.
 * \since 1.8
 *
 * \param ss7 SS7 linkset control structure.
 * \param chanpos Channel position in the span.
 * \param frame Frame to queue onto the owner channel.
 *
 * \note Assumes the ss7->lock is already obtained.
 * \note Assumes the sig_ss7_lock_private(ss7->pvts[chanpos]) is already obtained.
 *
 * \return Nothing
 */
static void sig_ss7_queue_frame(struct sig_ss7_linkset *ss7, int chanpos, struct ast_frame *frame)
{
	sig_ss7_lock_owner(ss7, chanpos);
	if (ss7->pvts[chanpos]->owner) {
		ast_queue_frame(ss7->pvts[chanpos]->owner, frame);
		ast_channel_unlock(ss7->pvts[chanpos]->owner);
	}
}

/*!
 * \internal
 * \brief Queue a control frame of the specified subclass onto the owner channel.
 * \since 1.8
 *
 * \param ss7 SS7 linkset control structure.
 * \param chanpos Channel position in the span.
 * \param subclass Control frame subclass to queue onto the owner channel.
 *
 * \note Assumes the ss7->lock is already obtained.
 * \note Assumes the sig_ss7_lock_private(ss7->pvts[chanpos]) is already obtained.
 *
 * \return Nothing
 */
static void sig_ss7_queue_control(struct sig_ss7_linkset *ss7, int chanpos, int subclass)
{
	struct ast_frame f = {AST_FRAME_CONTROL, };
	struct sig_ss7_chan *p = ss7->pvts[chanpos];

	if (sig_ss7_callbacks.queue_control) {
		sig_ss7_callbacks.queue_control(p->chan_pvt, subclass);
	}

	f.subclass.integer = subclass;
	sig_ss7_queue_frame(ss7, chanpos, &f);
}

/*!
 * \internal
 * \brief Queue a PVT_CAUSE_CODE frame onto the owner channel.
 * \since 11.0
 *
 * \param owner Owner channel of the pvt.
 * \param cause String describing the cause to be placed into the frame.
 *
 * \note Assumes the linkset->lock is already obtained.
 * \note Assumes the sig_ss7_lock_private(linkset->pvts[chanpos]) is already obtained.
 * \note Assumes linkset->pvts[chanpos]->owner is non-NULL and its lock is already obtained.
 *
 * \return Nothing
 */
static void ss7_queue_pvt_cause_data(struct ast_channel *owner, const char *cause, int ast_cause)
{
	struct ast_control_pvt_cause_code *cause_code;
	int datalen = sizeof(*cause_code) + strlen(cause);

	cause_code = ast_alloca(datalen);
	memset(cause_code, 0, datalen);
	cause_code->ast_cause = ast_cause;
	ast_copy_string(cause_code->chan_name, ast_channel_name(owner), AST_CHANNEL_NAME);
	ast_copy_string(cause_code->code, cause, datalen + 1 - sizeof(*cause_code));
	ast_queue_control_data(owner, AST_CONTROL_PVT_CAUSE_CODE, cause_code, datalen);
	ast_channel_hangupcause_hash_set(owner, cause_code, datalen);
}


/*!
 * \brief Find the channel position by CIC/DPC.
 *
 * \param linkset SS7 linkset control structure.
 * \param cic Circuit Identification Code
 * \param dpc Destination Point Code
 *
 * \retval chanpos on success.
 * \retval -1 on error.
 */
int sig_ss7_find_cic(struct sig_ss7_linkset *linkset, int cic, unsigned int dpc)
{
	int i;
	int winner = -1;
	for (i = 0; i < linkset->numchans; i++) {
		if (linkset->pvts[i] && (linkset->pvts[i]->dpc == dpc && linkset->pvts[i]->cic == cic)) {
			winner = i;
			break;
		}
	}
	return winner;
}

/*!
 * \internal
 * \brief Find the channel position by CIC/DPC and gripe if not found.
 *
 * \param linkset SS7 linkset control structure.
 * \param cic Circuit Identification Code
 * \param dpc Destination Point Code
 * \param msg_name Message type name that failed.
 *
 * \retval chanpos on success.
 * \retval -1 on error.
 */
static int ss7_find_cic_gripe(struct sig_ss7_linkset *linkset, int cic, unsigned int dpc, const char *msg_name)
{
	int chanpos;

	chanpos = sig_ss7_find_cic(linkset, cic, dpc);
	if (chanpos < 0) {
		ast_log(LOG_WARNING, "Linkset %d: SS7 %s requested on unconfigured CIC/DPC %d/%d.\n",
			linkset->span, msg_name, cic, dpc);
		return -1;
	}
	return chanpos;
}

static struct sig_ss7_chan *ss7_find_pvt(struct ss7 *ss7, int cic, unsigned int dpc)
{
	int chanpos;
	struct sig_ss7_linkset *winner;

	winner = sig_ss7_find_linkset(ss7);
	if (winner && (chanpos = sig_ss7_find_cic(winner, cic, dpc)) > -1) {
		return winner->pvts[chanpos];
	}
	return NULL;
}

int sig_ss7_cb_hangup(struct ss7 *ss7, int cic, unsigned int dpc, int cause, int do_hangup)
{
	struct sig_ss7_chan *p;
	int res;

	if (!(p = ss7_find_pvt(ss7, cic, dpc))) {
		return SS7_CIC_NOT_EXISTS;
	}

	sig_ss7_lock_private(p);
	if (p->owner) {
		ast_channel_hangupcause_set(p->owner, cause);
		ast_channel_softhangup_internal_flag_add(p->owner, AST_SOFTHANGUP_DEV);
		p->do_hangup = do_hangup;
		res = SS7_CIC_USED;
	} else {
		res = SS7_CIC_IDLE;
	}
	sig_ss7_unlock_private(p);

	return res;
}

void sig_ss7_cb_call_null(struct ss7 *ss7, struct isup_call *call, int lock)
{
	int i;
	struct sig_ss7_linkset *winner;

	winner = sig_ss7_find_linkset(ss7);
	if (!winner) {
		return;
	}
	for (i = 0; i < winner->numchans; i++) {
		if (winner->pvts[i] && (winner->pvts[i]->ss7call == call)) {
			if (lock) {
				sig_ss7_lock_private(winner->pvts[i]);
			}
			winner->pvts[i]->ss7call = NULL;
			if (winner->pvts[i]->owner) {
				ast_channel_hangupcause_set(winner->pvts[i]->owner, AST_CAUSE_NORMAL_TEMPORARY_FAILURE);
				ast_channel_softhangup_internal_flag_add(winner->pvts[i]->owner, AST_SOFTHANGUP_DEV);
			}
			if (lock) {
				sig_ss7_unlock_private(winner->pvts[i]);
			}
			ast_log(LOG_WARNING, "libss7 asked set ss7 call to NULL on CIC %d DPC %d\n", winner->pvts[i]->cic, winner->pvts[i]->dpc);
		}
	}
}

void sig_ss7_cb_notinservice(struct ss7 *ss7, int cic, unsigned int dpc)
{
	struct sig_ss7_chan *p;

	if (!(p = ss7_find_pvt(ss7, cic, dpc))) {
		return;
	}

	sig_ss7_lock_private(p);
	sig_ss7_set_inservice(p, 0);
	sig_ss7_unlock_private(p);
}

/*!
 * \internal
 * \brief Check if CICs in a range belong to the linkset for a given DPC.
 * \since 11.0
 *
 * \param linkset SS7 linkset control structure.
 * \param startcic Circuit Identification Code to start from
 * \param endcic Circuit Identification Code to search up-to
 * \param dpc Destination Point Code
 * \param state Array containing the status of the search
 *
 * \retval Nothing.
 */
static void ss7_check_range(struct sig_ss7_linkset *linkset, int startcic, int endcic, unsigned int dpc, unsigned char *state)
{
	int cic;

	for (cic = startcic; cic <= endcic; cic++) {
		if (state[cic - startcic] && sig_ss7_find_cic(linkset, cic, dpc) == -1) {
			state[cic - startcic] = 0;
		}
	}
}

static int ss7_match_range(struct sig_ss7_chan *pvt, int startcic, int endcic, unsigned int dpc)
{
	if (pvt && pvt->dpc == dpc && pvt->cic >= startcic && pvt->cic <= endcic) {
		return 1;
	}

	return 0;
}

/*!
 * \internal
 * \brief Check if a range is defined for the given DPC.
 * \since 11.0
 *
 * \param linkset SS7 linkset control structure.
 * \param startcic Start CIC of the range to clear.
 * \param endcic End CIC of the range to clear.
 * \param dpc Destination Point Code.
 *
 * \note Assumes the linkset->lock is already obtained.
 *
 * \return TRUE if all CICs in the range are present
 */
int sig_ss7_find_cic_range(struct sig_ss7_linkset *linkset, int startcic, int endcic, unsigned int dpc)
{
	int i, found = 0;

	for (i = 0; i < linkset->numchans; i++) {
		if (ss7_match_range(linkset->pvts[i], startcic, endcic, dpc)) {
			found++;
		}
	}

	if (found == endcic - startcic + 1) {
		return  1;
	}

	return 0;
}

static void ss7_handle_cqm(struct sig_ss7_linkset *linkset, ss7_event *e)
{
	unsigned char status[32];
	struct sig_ss7_chan *p = NULL;
	int i;
	int offset;
	int chanpos;

	memset(status, 0, sizeof(status));
	for (i = 0; i < linkset->numchans; i++) {
		if (ss7_match_range(linkset->pvts[i], e->cqm.startcic, e->cqm.endcic, e->cqm.opc)) {
			p = linkset->pvts[i];
			sig_ss7_lock_private(p);
			offset = p->cic - e->cqm.startcic;
			status[offset] = 0;
			if (p->locallyblocked) {
				status[offset] |= (1 << 0) | (1 << 4);
			}
			if (p->remotelyblocked) {
				status[offset] |= (1 << 1) | (1 << 5);
			}
			if (p->ss7call) {
				if (p->outgoing) {
					status[offset] |= (1 << 3);
				} else {
					status[offset] |= (1 << 2);
				}
			} else {
				status[offset] |= 0x3 << 2;
			}
			sig_ss7_unlock_private(p);
		}
	}

	if (p) {
		isup_cqr(linkset->ss7, e->cqm.startcic, e->cqm.endcic, e->cqm.opc, status);
	} else {
		ast_log(LOG_WARNING, "Could not find any equipped circuits within CQM CICs\n");
	}

	chanpos = sig_ss7_find_cic(linkset, e->cqm.startcic, e->cqm.opc);
	if (chanpos < 0) {
		isup_free_call(linkset->ss7, e->cqm.call);
		return;
	}
	p = linkset->pvts[chanpos];
	sig_ss7_lock_private(p);
	p->ss7call = e->cqm.call;
	if (!p->owner) {
		p->ss7call = isup_free_call_if_clear(linkset->ss7, e->cqm.call);
	}
	sig_ss7_unlock_private(p);
}

static inline void ss7_hangup_cics(struct sig_ss7_linkset *linkset, int startcic, int endcic, unsigned int dpc)
{
	int i;

	for (i = 0; i < linkset->numchans; i++) {
		if (ss7_match_range(linkset->pvts[i], startcic, endcic, dpc)) {
			sig_ss7_lock_private(linkset->pvts[i]);
			sig_ss7_lock_owner(linkset, i);
			if (linkset->pvts[i]->owner) {
				ast_softhangup_nolock(linkset->pvts[i]->owner, AST_SOFTHANGUP_DEV);
				ast_channel_unlock(linkset->pvts[i]->owner);
			}
			sig_ss7_unlock_private(linkset->pvts[i]);
		}
	}
}

/*!
 * \param linkset SS7 linkset control structure.
 * \param startcic Start CIC of the range to clear.
 * \param endcic End CIC of the range to clear.
 * \param dpc Destination Point Code.
 * \param state Affected CICs from the operation. NULL for all CICs in the range.
 * \param block Operation to perform. TRUE to block.
 * \param remotely Direction of the blocking. TRUE to block/unblock remotely.
 * \param type Blocking type - hardware or maintenance.
 *
 * \note Assumes the linkset->lock is already obtained.
 * \note Must be called without sig_ss7_lock_private() obtained.
 *
 * \return Nothing.
 */
static inline void ss7_block_cics(struct sig_ss7_linkset *linkset, int startcic, int endcic, unsigned int dpc, unsigned char state[], int block, int remotely, int type)
{
	int i;

	for (i = 0; i < linkset->numchans; i++) {
		if (ss7_match_range(linkset->pvts[i], startcic, endcic, dpc)) {
			sig_ss7_lock_private(linkset->pvts[i]);
			if (state) {
				if (state[linkset->pvts[i]->cic - startcic]) {

					if (remotely) {
						sig_ss7_set_remotelyblocked(linkset->pvts[i], block, type);
					} else {
						sig_ss7_set_locallyblocked(linkset->pvts[i], block, type);
					}

					sig_ss7_lock_owner(linkset, i);
					if (linkset->pvts[i]->owner) {
						if (ast_channel_state(linkset->pvts[i]->owner) == AST_STATE_DIALING
							&& linkset->pvts[i]->call_level < SIG_SS7_CALL_LEVEL_PROCEEDING) {
							ast_channel_hangupcause_set(linkset->pvts[i]->owner, SS7_CAUSE_TRY_AGAIN);
						}
						ast_channel_unlock(linkset->pvts[i]->owner);
					}
				}
			} else {
				if (remotely) {
					sig_ss7_set_remotelyblocked(linkset->pvts[i], block, type);
				} else {
					sig_ss7_set_locallyblocked(linkset->pvts[i], block, type);
				}
			}
			sig_ss7_unlock_private(linkset->pvts[i]);
		}
	}
}

/*!
 * \param linkset SS7 linkset control structure.
 * \param startcic Start CIC of the range to set in service.
 * \param endcic End CIC of the range to set in service.
 * \param dpc Destination Point Code.
 *
 * \note Must be called without sig_ss7_lock_private() obtained.
 *
 * \return Nothing.
 */
static void ss7_inservice(struct sig_ss7_linkset *linkset, int startcic, int endcic, unsigned int dpc)
{
	int i;

	for (i = 0; i < linkset->numchans; i++) {
		if (ss7_match_range(linkset->pvts[i], startcic, endcic, dpc)) {
			sig_ss7_lock_private(linkset->pvts[i]);
			sig_ss7_set_inservice(linkset->pvts[i], 1);
			sig_ss7_unlock_private(linkset->pvts[i]);
		}
	}
}

static int ss7_find_alloc_call(struct sig_ss7_chan *p)
{
	if (!p) {
		return 0;
	}

	if (!p->ss7call) {
		p->ss7call = isup_new_call(p->ss7->ss7, p->cic, p->dpc, 0);
		if (!p->ss7call) {
			return 0;
		}
	}
	return 1;
}

/*
 * XXX This routine is not tolerant of holes in the pvts[] array.
 * XXX This routine assumes the cic's in the pvts[] array are sorted.
 *
 * Probably the easiest way to deal with the invalid assumptions
 * is to have a local pvts[] array and sort it by dpc and cic.
 * Then the existing algorithm could work.
 */
static void ss7_reset_linkset(struct sig_ss7_linkset *linkset)
{
	int i, startcic, endcic, dpc;
	struct sig_ss7_chan *p;

	if (linkset->numchans <= 0) {
		return;
	}

	startcic = linkset->pvts[0]->cic;
	p = linkset->pvts[0];
	/* DB: CIC's DPC fix */
	dpc = linkset->pvts[0]->dpc;

	for (i = 0; i < linkset->numchans; i++) {
		if (linkset->pvts[i+1]
			&& linkset->pvts[i+1]->dpc == dpc
			&& linkset->pvts[i+1]->cic - linkset->pvts[i]->cic == 1
			&& linkset->pvts[i]->cic - startcic < (linkset->type == SS7_ANSI ? 24 : 31)) {
			continue;
		} else {
			endcic = linkset->pvts[i]->cic;
			ast_verb(1, "Resetting CICs %d to %d\n", startcic, endcic);

			sig_ss7_lock_private(p);
			if (!ss7_find_alloc_call(p)) {
				ast_log(LOG_ERROR, "Unable to allocate new ss7call\n");
			} else if (!(endcic - startcic)) {	/* GRS range can not be 0 - use RSC instead */
				isup_rsc(linkset->ss7, p->ss7call);
			} else {
				isup_grs(linkset->ss7, p->ss7call, endcic);
			}
			sig_ss7_unlock_private(p);

			/* DB: CIC's DPC fix */
			if (linkset->pvts[i+1]) {
				startcic = linkset->pvts[i+1]->cic;
				dpc = linkset->pvts[i+1]->dpc;
				p = linkset->pvts[i+1];
			}
		}
	}
}

/*!
 * \internal
 * \brief Complete the RSC procedure started earlier
 * \since 11.0
 *
 * \param p Signaling private structure pointer.
 *
 * \note Assumes the ss7->lock is already obtained.
 * \note Assumes sig_ss7_lock_private(p) is already obtained.
 *
 * \return Nothing.
 */
static void ss7_do_rsc(struct sig_ss7_chan *p)
{
	if (!p || !p->ss7call) {
		return;
	}

	isup_rsc(p->ss7->ss7, p->ss7call);

	if (p->locallyblocked & SS7_BLOCKED_MAINTENANCE) {
		isup_blo(p->ss7->ss7, p->ss7call);
	} else {
		sig_ss7_set_locallyblocked(p, 0, SS7_BLOCKED_MAINTENANCE | SS7_BLOCKED_HARDWARE);
	}
}

/*!
 * \internal
 * \brief Start RSC procedure on a specific link
 * \since 11.0
 *
 * \param ss7 SS7 linkset control structure.
 * \param which Channel position in the span.
 *
 * \note Assumes the ss7->lock is already obtained.
 * \note Assumes the sig_ss7_lock_private(ss7->pvts[chanpos]) is already obtained.
 *
 * \return TRUE on success
 */
static int ss7_start_rsc(struct sig_ss7_linkset *linkset, int which)
{
	if (!linkset->pvts[which]) {
		return 0;
	}

	if (!ss7_find_alloc_call(linkset->pvts[which])) {
		return 0;
	}

	sig_ss7_set_remotelyblocked(linkset->pvts[which], 0, SS7_BLOCKED_MAINTENANCE | SS7_BLOCKED_HARDWARE);
	sig_ss7_set_inservice(linkset->pvts[which], 0);
	sig_ss7_loopback(linkset->pvts[which], 0);

	sig_ss7_lock_owner(linkset, which);
	if (linkset->pvts[which]->owner) {
		ast_channel_hangupcause_set(linkset->pvts[which]->owner, AST_CAUSE_NORMAL_CLEARING);
		ast_softhangup_nolock(linkset->pvts[which]->owner, AST_SOFTHANGUP_DEV);
		ast_channel_unlock(linkset->pvts[which]->owner);
		linkset->pvts[which]->do_hangup = SS7_HANGUP_SEND_RSC;
	} else {
		ss7_do_rsc(linkset->pvts[which]);
	}

	return 1;
}

/*!
 * \internal
 * \brief Determine if a private channel structure is available.
 * \since 11.0
 *
 * \param linkset SS7 linkset control structure.
 * \param startcic Start CIC of the range to clear.
 * \param endcic End CIC of the range to clear.
 * \param dpc Destination Point Code.
 * \param do_hangup What we have to do to clear the call.
 *
 * \note Assumes the linkset->lock is already obtained.
 * \note Must be called without sig_ss7_lock_private() obtained.
 *
 * \return Nothing.
 */
static void ss7_clear_channels(struct sig_ss7_linkset *linkset, int startcic, int endcic, int dpc, int do_hangup)
{
	int i;

	for (i = 0; i < linkset->numchans; i++) {
		if (ss7_match_range(linkset->pvts[i], startcic, endcic, dpc)) {
			sig_ss7_lock_private(linkset->pvts[i]);
			sig_ss7_set_inservice(linkset->pvts[i], 0);
			sig_ss7_lock_owner(linkset, i);
			if (linkset->pvts[i]->owner) {
				ast_channel_hangupcause_set(linkset->pvts[i]->owner,
											AST_CAUSE_NORMAL_CLEARING);
				ast_softhangup_nolock(linkset->pvts[i]->owner, AST_SOFTHANGUP_DEV);
				ast_channel_unlock(linkset->pvts[i]->owner);
				linkset->pvts[i]->do_hangup = (linkset->pvts[i]->cic != startcic) ?
											do_hangup : SS7_HANGUP_DO_NOTHING;
			} else if (linkset->pvts[i] && linkset->pvts[i]->cic != startcic) {
				isup_free_call(linkset->pvts[i]->ss7->ss7, linkset->pvts[i]->ss7call);
				linkset->pvts[i]->ss7call = NULL;
			}
			sig_ss7_unlock_private(linkset->pvts[i]);
		}
	}
}

/*!
 * \internal
 *
 * \param p Signaling private structure pointer.
 * \param linkset SS7 linkset control structure.
 *
 * \note Assumes the linkset->lock is already obtained.
 * \note Assumes the sig_ss7_lock_private(ss7->pvts[chanpos]) is already obtained.
 *
 * \return Nothing.
 */
static void ss7_start_call(struct sig_ss7_chan *p, struct sig_ss7_linkset *linkset)
{
	struct ss7 *ss7 = linkset->ss7;
	int law;
	struct ast_channel *c;
	char tmp[256];
	char *strp;
	ast_callid callid = 0;
	int callid_created = ast_callid_threadstorage_auto(&callid);

	if (!(linkset->flags & LINKSET_FLAG_EXPLICITACM)) {
		p->call_level = SIG_SS7_CALL_LEVEL_PROCEEDING;
		isup_acm(ss7, p->ss7call);
	} else {
		p->call_level = SIG_SS7_CALL_LEVEL_SETUP;
	}

	/* Companding law is determined by SS7 signaling type. */
	if (linkset->type == SS7_ITU) {
		law = SIG_SS7_ALAW;
	} else {
		law = SIG_SS7_ULAW;
	}

	isup_set_echocontrol(p->ss7call, (linkset->flags & LINKSET_FLAG_DEFAULTECHOCONTROL) ? 1 : 0);

	/*
	 * Release the SS7 lock while we create the channel so other
	 * threads can send messages.  We must also release the private