Import pjproject-2.0.1

1 files changed, 1333 insertions, 0 deletions

diff --git a/pjsip/src/pjsip-ua/sip_reg.c b/pjsip/src/pjsip-ua/sip_reg.c
new file mode 100644
index 0000000..bd1fb21
--- /dev/null
+++ b/pjsip/src/pjsip-ua/sip_reg.c
@@ -0,0 +1,1333 @@
+/* $Id: sip_reg.c 4173 2012-06-20 10:39:05Z ming $ */
+/* 
+ * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com)
+ * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org>
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
+ */
+#include <pjsip-ua/sip_regc.h>
+#include <pjsip/sip_endpoint.h>
+#include <pjsip/sip_parser.h>
+#include <pjsip/sip_module.h>
+#include <pjsip/sip_transaction.h>
+#include <pjsip/sip_event.h>
+#include <pjsip/sip_util.h>
+#include <pjsip/sip_auth_msg.h>
+#include <pjsip/sip_errno.h>
+#include <pj/assert.h>
+#include <pj/guid.h>
+#include <pj/lock.h>
+#include <pj/os.h>
+#include <pj/pool.h>
+#include <pj/log.h>
+#include <pj/rand.h>
+#include <pj/string.h>
+
+
+#define REFRESH_TIMER		1
+#define DELAY_BEFORE_REFRESH    PJSIP_REGISTER_CLIENT_DELAY_BEFORE_REFRESH
+#define THIS_FILE		"sip_reg.c"
+
+/* Outgoing transaction timeout when server sends 100 but never replies
+ * with final response. Value is in MILISECONDS!
+ */
+#define REGC_TSX_TIMEOUT	33000
+
+enum { NOEXP = 0x1FFFFFFF };
+
+static const pj_str_t XUID_PARAM_NAME = { "x-uid", 5 };
+
+
+/* Current/pending operation */
+enum regc_op
+{
+    REGC_IDLE,
+    REGC_REGISTERING,
+    REGC_UNREGISTERING
+};
+
+/**
+ * SIP client registration structure.
+ */
+struct pjsip_regc
+{
+    pj_pool_t			*pool;
+    pjsip_endpoint		*endpt;
+    pj_lock_t			*lock;
+    pj_bool_t			 _delete_flag;
+    pj_bool_t			 has_tsx;
+    pj_atomic_t			*busy_ctr;
+    enum regc_op		 current_op;
+
+    pj_bool_t			 add_xuid_param;
+
+    void			*token;
+    pjsip_regc_cb		*cb;
+
+    pj_str_t			 str_srv_url;
+    pjsip_uri			*srv_url;
+    pjsip_cid_hdr		*cid_hdr;
+    pjsip_cseq_hdr		*cseq_hdr;
+    pj_str_t			 from_uri;
+    pjsip_from_hdr		*from_hdr;
+    pjsip_to_hdr		*to_hdr;
+    pjsip_contact_hdr		 contact_hdr_list;
+    pjsip_contact_hdr		 removed_contact_hdr_list;
+    pjsip_expires_hdr		*expires_hdr;
+    pj_uint32_t			 expires;
+    pj_uint32_t			 delay_before_refresh;
+    pjsip_route_hdr		 route_set;
+    pjsip_hdr			 hdr_list;
+    pjsip_host_port              via_addr;
+    const void                  *via_tp;
+
+    /* Authorization sessions. */
+    pjsip_auth_clt_sess		 auth_sess;
+
+    /* Auto refresh registration. */
+    pj_bool_t			 auto_reg;
+    pj_time_val			 last_reg;
+    pj_time_val			 next_reg;
+    pj_timer_entry		 timer;
+
+    /* Transport selector */
+    pjsip_tpselector		 tp_sel;
+
+    /* Last transport used. We acquire the transport to keep
+     * it open.
+     */
+    pjsip_transport		*last_transport;
+};
+
+
+PJ_DEF(pj_status_t) pjsip_regc_create( pjsip_endpoint *endpt, void *token,
+				       pjsip_regc_cb *cb,
+				       pjsip_regc **p_regc)
+{
+    pj_pool_t *pool;
+    pjsip_regc *regc;
+    pj_status_t status;
+
+    /* Verify arguments. */
+    PJ_ASSERT_RETURN(endpt && cb && p_regc, PJ_EINVAL);
+
+    pool = pjsip_endpt_create_pool(endpt, "regc%p", 1024, 1024);
+    PJ_ASSERT_RETURN(pool != NULL, PJ_ENOMEM);
+
+    regc = PJ_POOL_ZALLOC_T(pool, pjsip_regc);
+
+    regc->pool = pool;
+    regc->endpt = endpt;
+    regc->token = token;
+    regc->cb = cb;
+    regc->expires = PJSIP_REGC_EXPIRATION_NOT_SPECIFIED;
+    regc->add_xuid_param = pjsip_cfg()->regc.add_xuid_param;
+
+    status = pj_lock_create_recursive_mutex(pool, pool->obj_name, 
+					    &regc->lock);
+    if (status != PJ_SUCCESS) {
+	pj_pool_release(pool);
+	return status;
+    }
+
+    status = pj_atomic_create(pool, 0, &regc->busy_ctr);
+    if (status != PJ_SUCCESS) {
+	pj_lock_destroy(regc->lock);
+	pj_pool_release(pool);
+	return status;
+    }
+
+    status = pjsip_auth_clt_init(&regc->auth_sess, endpt, regc->pool, 0);
+    if (status != PJ_SUCCESS)
+	return status;
+
+    pj_list_init(&regc->route_set);
+    pj_list_init(&regc->hdr_list);
+    pj_list_init(&regc->contact_hdr_list);
+    pj_list_init(&regc->removed_contact_hdr_list);
+
+    /* Done */
+    *p_regc = regc;
+    return PJ_SUCCESS;
+}
+
+
+PJ_DEF(pj_status_t) pjsip_regc_destroy(pjsip_regc *regc)
+{
+    PJ_ASSERT_RETURN(regc, PJ_EINVAL);
+
+    pj_lock_acquire(regc->lock);
+    if (regc->has_tsx || pj_atomic_get(regc->busy_ctr) != 0) {
+	regc->_delete_flag = 1;
+	regc->cb = NULL;
+	pj_lock_release(regc->lock);
+    } else {
+	pjsip_tpselector_dec_ref(&regc->tp_sel);
+	if (regc->last_transport) {
+	    pjsip_transport_dec_ref(regc->last_transport);
+	    regc->last_transport = NULL;
+	}
+	if (regc->timer.id != 0) {
+	    pjsip_endpt_cancel_timer(regc->endpt, &regc->timer);
+	    regc->timer.id = 0;
+	}
+	pj_atomic_destroy(regc->busy_ctr);
+	pj_lock_release(regc->lock);
+	pj_lock_destroy(regc->lock);
+	regc->lock = NULL;
+	pjsip_endpt_release_pool(regc->endpt, regc->pool);
+    }
+
+    return PJ_SUCCESS;
+}
+
+
+PJ_DEF(pj_status_t) pjsip_regc_get_info( pjsip_regc *regc,
+					 pjsip_regc_info *info )
+{
+    PJ_ASSERT_RETURN(regc && info, PJ_EINVAL);
+
+    pj_lock_acquire(regc->lock);
+
+    info->server_uri = regc->str_srv_url;
+    info->client_uri = regc->from_uri;
+    info->is_busy = (pj_atomic_get(regc->busy_ctr) || regc->has_tsx);
+    info->auto_reg = regc->auto_reg;
+    info->interval = regc->expires;
+    info->transport = regc->last_transport;
+    
+    if (regc->has_tsx)
+	info->next_reg = 0;
+    else if (regc->auto_reg == 0)
+	info->next_reg = 0;
+    else if (regc->expires < 0)
+	info->next_reg = regc->expires;
+    else {
+	pj_time_val now, next_reg;
+
+	next_reg = regc->next_reg;
+	pj_gettimeofday(&now);
+	PJ_TIME_VAL_SUB(next_reg, now);
+	info->next_reg = next_reg.sec;
+    }
+
+    pj_lock_release(regc->lock);
+
+    return PJ_SUCCESS;
+}
+
+
+PJ_DEF(pj_pool_t*) pjsip_regc_get_pool(pjsip_regc *regc)
+{
+    return regc->pool;
+}
+
+static void set_expires( pjsip_regc *regc, pj_uint32_t expires)
+{
+    if (expires != regc->expires) {
+	regc->expires_hdr = pjsip_expires_hdr_create(regc->pool, expires);
+    } else {
+	regc->expires_hdr = NULL;
+    }
+}
+
+
+static pj_status_t set_contact( pjsip_regc *regc,
+			        int contact_cnt,
+				const pj_str_t contact[] )
+{
+    const pj_str_t CONTACT = { "Contact", 7 };
+    pjsip_contact_hdr *h;
+    int i;
+    
+    /* Save existing contact list to removed_contact_hdr_list and
+     * clear contact_hdr_list.
+     */
+    pj_list_merge_last(&regc->removed_contact_hdr_list, 
+		       &regc->contact_hdr_list);
+
+    /* Set the expiration of Contacts in to removed_contact_hdr_list 
+     * zero.
+     */
+    h = regc->removed_contact_hdr_list.next;
+    while (h != &regc->removed_contact_hdr_list) {
+	h->expires = 0;
+	h = h->next;
+    }
+
+    /* Process new contacts */
+    for (i=0; i<contact_cnt; ++i) {
+	pjsip_contact_hdr *hdr;
+	pj_str_t tmp;
+
+	pj_strdup_with_null(regc->pool, &tmp, &contact[i]);
+	hdr = (pjsip_contact_hdr*)
+              pjsip_parse_hdr(regc->pool, &CONTACT, tmp.ptr, tmp.slen, NULL);
+	if (hdr == NULL) {
+	    PJ_LOG(4,(THIS_FILE, "Invalid Contact: \"%.*s\"", 
+		     (int)tmp.slen, tmp.ptr));
+	    return PJSIP_EINVALIDURI;
+	}
+
+	/* Find the new contact in old contact list. If found, remove
+	 * the old header from the old header list.
+	 */
+	h = regc->removed_contact_hdr_list.next;
+	while (h != &regc->removed_contact_hdr_list) {
+	    int rc;
+
+	    rc = pjsip_uri_cmp(PJSIP_URI_IN_CONTACT_HDR, 
+			       h->uri, hdr->uri);
+	    if (rc == 0) {
+		/* Match */
+		pj_list_erase(h);
+		break;
+	    }
+
+	    h = h->next;
+	}
+
+	/* If add_xuid_param option is enabled and Contact URI is sip/sips,
+	 * add xuid parameter to assist matching the Contact URI in the 
+	 * REGISTER response later.
+	 */
+	if (regc->add_xuid_param && (PJSIP_URI_SCHEME_IS_SIP(hdr->uri) ||
+				     PJSIP_URI_SCHEME_IS_SIPS(hdr->uri))) 
+	{
+	    pjsip_param *xuid_param;
+	    pjsip_sip_uri *sip_uri;
+
+	    xuid_param = PJ_POOL_ZALLOC_T(regc->pool, pjsip_param);
+	    xuid_param->name = XUID_PARAM_NAME;
+	    pj_create_unique_string(regc->pool, &xuid_param->value);
+
+	    sip_uri = (pjsip_sip_uri*) pjsip_uri_get_uri(hdr->uri);
+	    pj_list_push_back(&sip_uri->other_param, xuid_param);
+	}
+
+	pj_list_push_back(&regc->contact_hdr_list, hdr);
+    }
+
+    return PJ_SUCCESS;
+}
+
+
+PJ_DEF(pj_status_t) pjsip_regc_init( pjsip_regc *regc,
+				     const pj_str_t *srv_url,
+				     const pj_str_t *from_url,
+				     const pj_str_t *to_url,
+				     int contact_cnt,
+				     const pj_str_t contact[],
+				     pj_uint32_t expires)
+{
+    pj_str_t tmp;
+    pj_status_t status;
+
+    PJ_ASSERT_RETURN(regc && srv_url && from_url && to_url && 
+		     contact_cnt && contact && expires, PJ_EINVAL);
+
+    /* Copy server URL. */
+    pj_strdup_with_null(regc->pool, &regc->str_srv_url, srv_url);
+
+    /* Set server URL. */
+    tmp = regc->str_srv_url;
+    regc->srv_url = pjsip_parse_uri( regc->pool, tmp.ptr, tmp.slen, 0);
+    if (regc->srv_url == NULL) {
+	return PJSIP_EINVALIDURI;
+    }
+
+    /* Set "From" header. */
+    pj_strdup_with_null(regc->pool, &regc->from_uri, from_url);
+    tmp = regc->from_uri;
+    regc->from_hdr = pjsip_from_hdr_create(regc->pool);
+    regc->from_hdr->uri = pjsip_parse_uri(regc->pool, tmp.ptr, tmp.slen, 
+					  PJSIP_PARSE_URI_AS_NAMEADDR);
+    if (!regc->from_hdr->uri) {
+	PJ_LOG(4,(THIS_FILE, "regc: invalid source URI %.*s", 
+		  from_url->slen, from_url->ptr));
+	return PJSIP_EINVALIDURI;
+    }
+
+    /* Set "To" header. */
+    pj_strdup_with_null(regc->pool, &tmp, to_url);
+    regc->to_hdr = pjsip_to_hdr_create(regc->pool);
+    regc->to_hdr->uri = pjsip_parse_uri(regc->pool, tmp.ptr, tmp.slen, 
+					PJSIP_PARSE_URI_AS_NAMEADDR);
+    if (!regc->to_hdr->uri) {
+	PJ_LOG(4,(THIS_FILE, "regc: invalid target URI %.*s", to_url->slen, to_url->ptr));
+	return PJSIP_EINVALIDURI;
+    }
+
+
+    /* Set "Contact" header. */
+    status = set_contact( regc, contact_cnt, contact);
+    if (status != PJ_SUCCESS)
+	return status;
+
+    /* Set "Expires" header, if required. */
+    set_expires( regc, expires);
+    regc->delay_before_refresh = DELAY_BEFORE_REFRESH;
+
+    /* Set "Call-ID" header. */
+    regc->cid_hdr = pjsip_cid_hdr_create(regc->pool);
+    pj_create_unique_string(regc->pool, &regc->cid_hdr->id);
+
+    /* Set "CSeq" header. */
+    regc->cseq_hdr = pjsip_cseq_hdr_create(regc->pool);
+    regc->cseq_hdr->cseq = pj_rand() % 0xFFFF;
+    pjsip_method_set( &regc->cseq_hdr->method, PJSIP_REGISTER_METHOD);
+
+    /* Done. */
+    return PJ_SUCCESS;
+}
+
+PJ_DEF(pj_status_t) pjsip_regc_set_credentials( pjsip_regc *regc,
+						int count,
+						const pjsip_cred_info cred[] )
+{
+    PJ_ASSERT_RETURN(regc && count && cred, PJ_EINVAL);
+    return pjsip_auth_clt_set_credentials(&regc->auth_sess, count, cred);
+}
+
+PJ_DEF(pj_status_t) pjsip_regc_set_prefs( pjsip_regc *regc,
+					  const pjsip_auth_clt_pref *pref)
+{
+    PJ_ASSERT_RETURN(regc && pref, PJ_EINVAL);
+    return pjsip_auth_clt_set_prefs(&regc->auth_sess, pref);
+}
+
+PJ_DEF(pj_status_t) pjsip_regc_set_route_set( pjsip_regc *regc,
+					      const pjsip_route_hdr *route_set)
+{
+    const pjsip_route_hdr *chdr;
+
+    PJ_ASSERT_RETURN(regc && route_set, PJ_EINVAL);
+
+    pj_list_init(&regc->route_set);
+
+    chdr = route_set->next;
+    while (chdr != route_set) {
+	pj_list_push_back(&regc->route_set, pjsip_hdr_clone(regc->pool, chdr));
+	chdr = chdr->next;
+    }
+
+    return PJ_SUCCESS;
+}
+
+
+/*
+ * Bind client registration to a specific transport/listener. 
+ */
+PJ_DEF(pj_status_t) pjsip_regc_set_transport( pjsip_regc *regc,
+					      const pjsip_tpselector *sel)
+{
+    PJ_ASSERT_RETURN(regc && sel, PJ_EINVAL);
+
+    pjsip_tpselector_dec_ref(&regc->tp_sel);
+    pj_memcpy(&regc->tp_sel, sel, sizeof(*sel));
+    pjsip_tpselector_add_ref(&regc->tp_sel);
+
+    return PJ_SUCCESS;
+}
+
+/* Release transport */
+PJ_DEF(pj_status_t) pjsip_regc_release_transport(pjsip_regc *regc)
+{
+    PJ_ASSERT_RETURN(regc, PJ_EINVAL);
+    if (regc->last_transport) {
+	pjsip_transport_dec_ref(regc->last_transport);
+	regc->last_transport = NULL;
+    }
+    return PJ_SUCCESS;
+}
+
+
+PJ_DEF(pj_status_t) pjsip_regc_add_headers( pjsip_regc *regc,
+					    const pjsip_hdr *hdr_list)
+{
+    const pjsip_hdr *hdr;
+
+    PJ_ASSERT_RETURN(regc && hdr_list, PJ_EINVAL);
+
+    //This is "add" operation, so don't remove headers.
+    //pj_list_init(&regc->hdr_list);
+
+    hdr = hdr_list->next;
+    while (hdr != hdr_list) {
+	pj_list_push_back(&regc->hdr_list, pjsip_hdr_clone(regc->pool, hdr));
+	hdr = hdr->next;
+    }
+
+    return PJ_SUCCESS;
+}
+
+static pj_status_t create_request(pjsip_regc *regc, 
+				  pjsip_tx_data **p_tdata)
+{
+    pj_status_t status;
+    pjsip_tx_data *tdata;
+
+    PJ_ASSERT_RETURN(regc && p_tdata, PJ_EINVAL);
+
+    /* Create the request. */
+    status = pjsip_endpt_create_request_from_hdr( regc->endpt, 
+						  pjsip_get_register_method(),
+						  regc->srv_url,
+						  regc->from_hdr,
+						  regc->to_hdr,
+						  NULL,
+						  regc->cid_hdr,
+						  regc->cseq_hdr->cseq,
+						  NULL,
+						  &tdata);
+    if (status != PJ_SUCCESS)
+	return status;
+
+    /* Add cached authorization headers. */
+    pjsip_auth_clt_init_req( &regc->auth_sess, tdata );
+
+    /* Add Route headers from route set, ideally after Via header */
+    if (!pj_list_empty(&regc->route_set)) {
+	pjsip_hdr *route_pos;
+	const pjsip_route_hdr *route;
+
+	route_pos = (pjsip_hdr*)
+		    pjsip_msg_find_hdr(tdata->msg, PJSIP_H_VIA, NULL);
+	if (!route_pos)
+	    route_pos = &tdata->msg->hdr;
+
+	route = regc->route_set.next;
+	while (route != &regc->route_set) {
+	    pjsip_hdr *new_hdr = (pjsip_hdr*)
+				 pjsip_hdr_shallow_clone(tdata->pool, route);
+	    pj_list_insert_after(route_pos, new_hdr);
+	    route_pos = new_hdr;
+	    route = route->next;
+	}
+    }
+
+    /* Add additional request headers */
+    if (!pj_list_empty(&regc->hdr_list)) {
+	const pjsip_hdr *hdr;
+
+	hdr = regc->hdr_list.next;
+	while (hdr != &regc->hdr_list) {
+	    pjsip_hdr *new_hdr = (pjsip_hdr*)
+				 pjsip_hdr_shallow_clone(tdata->pool, hdr);
+	    pjsip_msg_add_hdr(tdata->msg, new_hdr);
+	    hdr = hdr->next;
+	}
+    }
+
+    /* Done. */
+    *p_tdata = tdata;
+    return PJ_SUCCESS;
+}
+
+
+PJ_DEF(pj_status_t) pjsip_regc_register(pjsip_regc *regc, pj_bool_t autoreg,
+					pjsip_tx_data **p_tdata)
+{
+    pjsip_msg *msg;
+    pjsip_contact_hdr *hdr;
+    const pjsip_hdr *h_allow;
+    pj_status_t status;
+    pjsip_tx_data *tdata;
+
+    PJ_ASSERT_RETURN(regc && p_tdata, PJ_EINVAL);
+
+    pj_lock_acquire(regc->lock);
+
+    status = create_request(regc, &tdata);
+    if (status != PJ_SUCCESS) {
+	pj_lock_release(regc->lock);
+	return status;
+    }
+
+    msg = tdata->msg;
+
+    /* Add Contact headers. */
+    hdr = regc->contact_hdr_list.next;
+    while (hdr != &regc->contact_hdr_list) {
+	pjsip_msg_add_hdr(msg, (pjsip_hdr*)
+			       pjsip_hdr_shallow_clone(tdata->pool, hdr));
+	hdr = hdr->next;
+    }
+
+    /* Also add bindings which are to be removed */
+    while (!pj_list_empty(&regc->removed_contact_hdr_list)) {
+	hdr = regc->removed_contact_hdr_list.next;
+	pjsip_msg_add_hdr(msg, (pjsip_hdr*)
+			       pjsip_hdr_clone(tdata->pool, hdr));
+	pj_list_erase(hdr);
+    }
+    
+
+    if (regc->expires_hdr)
+	pjsip_msg_add_hdr(msg, (pjsip_hdr*)
+			       pjsip_hdr_shallow_clone(tdata->pool,
+						       regc->expires_hdr));
+
+    if (regc->timer.id != 0) {
+	pjsip_endpt_cancel_timer(regc->endpt, &regc->timer);
+	regc->timer.id = 0;
+    }
+
+    /* Add Allow header (http://trac.pjsip.org/repos/ticket/1039) */
+    h_allow = pjsip_endpt_get_capability(regc->endpt, PJSIP_H_ALLOW, NULL);
+    if (h_allow) {
+	pjsip_msg_add_hdr(msg, (pjsip_hdr*)
+			       pjsip_hdr_shallow_clone(tdata->pool, h_allow));
+
+    }
+
+    regc->auto_reg = autoreg;
+
+    pj_lock_release(regc->lock);
+
+    /* Done */
+    *p_tdata = tdata;
+    return PJ_SUCCESS;
+}
+
+
+PJ_DEF(pj_status_t) pjsip_regc_unregister(pjsip_regc *regc,
+					  pjsip_tx_data **p_tdata)
+{
+    pjsip_tx_data *tdata;
+    pjsip_msg *msg;
+    pjsip_hdr *hdr;
+    pj_status_t status;
+
+    PJ_ASSERT_RETURN(regc && p_tdata, PJ_EINVAL);
+
+    pj_lock_acquire(regc->lock);
+
+    if (regc->timer.id != 0) {
+	pjsip_endpt_cancel_timer(regc->endpt, &regc->timer);
+	regc->timer.id = 0;
+    }
+
+    status = create_request(regc, &tdata);
+    if (status != PJ_SUCCESS) {
+	pj_lock_release(regc->lock);
+	return status;
+    }
+
+    msg = tdata->msg;
+
+    /* Add Contact headers. */
+    hdr = (pjsip_hdr*)regc->contact_hdr_list.next;
+    while ((void*)hdr != (void*)&regc->contact_hdr_list) {
+	pjsip_msg_add_hdr(msg, (pjsip_hdr*)
+			       pjsip_hdr_shallow_clone(tdata->pool, hdr));
+	hdr = hdr->next;
+    }
+
+    /* Also add bindings which are to be removed */
+    while (!pj_list_empty(&regc->removed_contact_hdr_list)) {
+	hdr = (pjsip_hdr*)regc->removed_contact_hdr_list.next;
+	pjsip_msg_add_hdr(msg, (pjsip_hdr*)
+			       pjsip_hdr_clone(tdata->pool, hdr));
+	pj_list_erase(hdr);
+    }
+
+    /* Add Expires:0 header */
+    hdr = (pjsip_hdr*) pjsip_expires_hdr_create(tdata->pool, 0);
+    pjsip_msg_add_hdr(msg, hdr);
+
+    pj_lock_release(regc->lock);
+
+    *p_tdata = tdata;
+    return PJ_SUCCESS;
+}
+
+PJ_DEF(pj_status_t) pjsip_regc_unregister_all(pjsip_regc *regc,
+					      pjsip_tx_data **p_tdata)
+{
+    pjsip_tx_data *tdata;
+    pjsip_contact_hdr *hcontact;
+    pjsip_hdr *hdr;
+    pjsip_msg *msg;
+    pj_status_t status;
+
+    PJ_ASSERT_RETURN(regc && p_tdata, PJ_EINVAL);
+
+    pj_lock_acquire(regc->lock);
+
+    if (regc->timer.id != 0) {
+	pjsip_endpt_cancel_timer(regc->endpt, &regc->timer);
+	regc->timer.id = 0;
+    }
+
+    status = create_request(regc, &tdata);
+    if (status != PJ_SUCCESS) {
+	pj_lock_release(regc->lock);
+	return status;
+    }
+
+    msg = tdata->msg;
+
+    /* Clear removed_contact_hdr_list */
+    pj_list_init(&regc->removed_contact_hdr_list);
+
+    /* Add Contact:* header */
+    hcontact = pjsip_contact_hdr_create(tdata->pool);
+    hcontact->star = 1;
+    pjsip_msg_add_hdr(msg, (pjsip_hdr*)hcontact);
+    
+    /* Add Expires:0 header */
+    hdr = (pjsip_hdr*) pjsip_expires_hdr_create(tdata->pool, 0);
+    pjsip_msg_add_hdr(msg, hdr);
+
+    pj_lock_release(regc->lock);
+
+    *p_tdata = tdata;
+    return PJ_SUCCESS;
+}
+
+
+PJ_DEF(pj_status_t) pjsip_regc_update_contact(  pjsip_regc *regc,
+					        int contact_cnt,
+						const pj_str_t contact[] )
+{
+    pj_status_t status;
+
+    PJ_ASSERT_RETURN(regc, PJ_EINVAL);
+
+    pj_lock_acquire(regc->lock);
+    status = set_contact( regc, contact_cnt, contact );
+    pj_lock_release(regc->lock);
+
+    return status;
+}
+
+
+PJ_DEF(pj_status_t) pjsip_regc_update_expires(  pjsip_regc *regc,
+					        pj_uint32_t expires )
+{
+    PJ_ASSERT_RETURN(regc, PJ_EINVAL);
+
+    pj_lock_acquire(regc->lock);
+    set_expires( regc, expires );
+    pj_lock_release(regc->lock);
+
+    return PJ_SUCCESS;
+}
+
+
+static void call_callback(pjsip_regc *regc, pj_status_t status, int st_code, 
+			  const pj_str_t *reason,
+			  pjsip_rx_data *rdata, pj_int32_t expiration,
+			  int contact_cnt, pjsip_contact_hdr *contact[])
+{
+    struct pjsip_regc_cbparam cbparam;
+
+
+    if (!regc->cb)
+	return;
+
+    cbparam.regc = regc;
+    cbparam.token = regc->token;
+    cbparam.status = status;
+    cbparam.code = st_code;
+    cbparam.reason = *reason;
+    cbparam.rdata = rdata;
+    cbparam.contact_cnt = contact_cnt;
+    cbparam.expiration = expiration;
+    if (contact_cnt) {
+	pj_memcpy( cbparam.contact, contact, 
+		   contact_cnt*sizeof(pjsip_contact_hdr*));
+    }
+
+    (*regc->cb)(&cbparam);
+}
+
+static void regc_refresh_timer_cb( pj_timer_heap_t *timer_heap,
+				   struct pj_timer_entry *entry)
+{
+    pjsip_regc *regc = (pjsip_regc*) entry->user_data;
+    pjsip_tx_data *tdata;
+    pj_status_t status;
+    
+    PJ_UNUSED_ARG(timer_heap);
+
+    /* Temporarily increase busy flag to prevent regc from being deleted
+     * in pjsip_regc_send() or in the callback
+     */
+    pj_atomic_inc(regc->busy_ctr);
+
+    entry->id = 0;
+    status = pjsip_regc_register(regc, 1, &tdata);
+    if (status == PJ_SUCCESS) {
+	status = pjsip_regc_send(regc, tdata);
+    } 
+    
+    if (status != PJ_SUCCESS && regc->cb) {
+	char errmsg[PJ_ERR_MSG_SIZE];
+	pj_str_t reason = pj_strerror(status, errmsg, sizeof(errmsg));
+	call_callback(regc, status, 400, &reason, NULL, -1, 0, NULL);
+    }
+
+    /* Delete the record if user destroy regc during the callback. */
+    if (pj_atomic_dec_and_get(regc->busy_ctr)==0 && regc->_delete_flag) {
+	pjsip_regc_destroy(regc);
+    }
+}
+
+static void schedule_registration ( pjsip_regc *regc, pj_int32_t expiration )
+{
+    if (regc->auto_reg && expiration > 0) {
+        pj_time_val delay = { 0, 0};
+
+        delay.sec = expiration - regc->delay_before_refresh;
+        if (regc->expires != PJSIP_REGC_EXPIRATION_NOT_SPECIFIED && 
+            delay.sec > (pj_int32_t)regc->expires) 
+        {
+            delay.sec = regc->expires;
+        }
+        if (delay.sec < DELAY_BEFORE_REFRESH) 
+            delay.sec = DELAY_BEFORE_REFRESH;
+        regc->timer.cb = &regc_refresh_timer_cb;
+        regc->timer.id = REFRESH_TIMER;
+        regc->timer.user_data = regc;
+        pjsip_endpt_schedule_timer( regc->endpt, &regc->timer, &delay);
+        pj_gettimeofday(&regc->last_reg);
+        regc->next_reg = regc->last_reg;
+        regc->next_reg.sec += delay.sec;
+    }
+}
+
+PJ_DEF(pj_status_t) pjsip_regc_set_via_sent_by( pjsip_regc *regc,
+				                pjsip_host_port *via_addr,
+                                                pjsip_transport *via_tp)
+{
+    PJ_ASSERT_RETURN(regc, PJ_EINVAL);
+
+    if (!via_addr)
+        pj_bzero(&regc->via_addr, sizeof(regc->via_addr));
+    else
+        regc->via_addr = *via_addr;
+    regc->via_tp = via_tp;
+
+    return PJ_SUCCESS;
+}
+
+PJ_DEF(pj_status_t)
+pjsip_regc_set_delay_before_refresh( pjsip_regc *regc,
+				     pj_uint32_t delay )
+{
+    PJ_ASSERT_RETURN(regc, PJ_EINVAL);
+
+    if (delay > regc->expires)
+        return PJ_ETOOBIG;
+
+    if (regc->delay_before_refresh != delay)
+    {
+        regc->delay_before_refresh = delay;
+
+        if (regc->timer.id != 0) {
+            /* Cancel registration timer */
+            pjsip_endpt_cancel_timer(regc->endpt, &regc->timer);
+            regc->timer.id = 0;
+
+            /* Schedule next registration */
+            schedule_registration(regc, regc->expires);
+        }
+    }
+
+    return PJ_SUCCESS;
+}
+
+
+static pj_int32_t calculate_response_expiration(const pjsip_regc *regc,
+					        const pjsip_rx_data *rdata,
+						unsigned *contact_cnt,
+						unsigned max_contact,
+						pjsip_contact_hdr *contacts[])
+{
+    pj_int32_t expiration = NOEXP;
+    const pjsip_msg *msg = rdata->msg_info.msg;
+    const pjsip_hdr *hdr;
+
+    /* Enumerate all Contact headers in the response */
+    *contact_cnt = 0;
+    for (hdr=msg->hdr.next; hdr!=&msg->hdr; hdr=hdr->next) {
+	if (hdr->type == PJSIP_H_CONTACT && 
+	    *contact_cnt < max_contact) 
+	{
+	    contacts[*contact_cnt] = (pjsip_contact_hdr*)hdr;
+	    ++(*contact_cnt);
+	}
+    }
+
+    if (regc->current_op == REGC_REGISTERING) {
+	pj_bool_t has_our_contact = PJ_FALSE;
+	const pjsip_expires_hdr *expires;
+
+	/* Get Expires header */
+	expires = (const pjsip_expires_hdr*)
+		  pjsip_msg_find_hdr(msg, PJSIP_H_EXPIRES, NULL);
+
+	/* Try to find the Contact URIs that we register, in the response
+	 * to get the expires value. We'll try both with comparing the URI
+	 * and comparing the extension param only.
+	 */
+	if (pjsip_cfg()->regc.check_contact || regc->add_xuid_param) {
+	    unsigned i;
+	    for (i=0; i<*contact_cnt; ++i) {
+		const pjsip_contact_hdr *our_hdr;
+
+		our_hdr = (const pjsip_contact_hdr*) 
+			  regc->contact_hdr_list.next;
+
+		/* Match with our Contact header(s) */
+		while ((void*)our_hdr != (void*)&regc->contact_hdr_list) {
+
+		    const pjsip_uri *uri1, *uri2;
+		    pj_bool_t matched = PJ_FALSE;
+
+		    /* Exclude the display name when comparing the URI 
+		     * since server may not return it.
+		     */
+		    uri1 = (const pjsip_uri*)
+			   pjsip_uri_get_uri(contacts[i]->uri);
+		    uri2 = (const pjsip_uri*)
+			   pjsip_uri_get_uri(our_hdr->uri);
+
+		    /* First try with exact matching, according to RFC 3261
+		     * Section 19.1.4 URI Comparison
+		     */
+		    if (pjsip_cfg()->regc.check_contact) {
+			matched = pjsip_uri_cmp(PJSIP_URI_IN_CONTACT_HDR,
+						uri1, uri2)==0;
+		    }
+
+		    /* If no match is found, try with matching the extension
+		     * parameter only if extension parameter was added.
+		     */
+		    if (!matched && regc->add_xuid_param &&
+			(PJSIP_URI_SCHEME_IS_SIP(uri1) ||
+			 PJSIP_URI_SCHEME_IS_SIPS(uri1)) && 
+			(PJSIP_URI_SCHEME_IS_SIP(uri2) ||
+			 PJSIP_URI_SCHEME_IS_SIPS(uri2))) 
+		    {
+			const pjsip_sip_uri *sip_uri1, *sip_uri2;
+			const pjsip_param *p1, *p2;
+		
+			sip_uri1 = (const pjsip_sip_uri*)uri1;
+			sip_uri2 = (const pjsip_sip_uri*)uri2;
+
+			p1 = pjsip_param_cfind(&sip_uri1->other_param,
+					       &XUID_PARAM_NAME);
+			p2 = pjsip_param_cfind(&sip_uri2->other_param,
+					       &XUID_PARAM_NAME);
+			matched = p1 && p2 &&
+				  pj_strcmp(&p1->value, &p2->value)==0;
+
+		    }
+
+		    if (matched) {
+			has_our_contact = PJ_TRUE;
+
+			if (contacts[i]->expires >= 0 && 
+			    contacts[i]->expires < expiration) 
+			{
+			    /* Get the lowest expiration time. */
+			    expiration = contacts[i]->expires;
+			}
+
+			break;
+		    }
+
+		    our_hdr = our_hdr->next;
+
+		} /* while ((void.. */
+
+	    }  /* for (i=.. */
+
+	    /* If matching Contact header(s) are found but the
+	     * header doesn't contain expires parameter, get the
+	     * expiration value from the Expires header. And
+	     * if Expires header is not present, get the expiration
+	     * value from the request.
+	     */
+	    if (has_our_contact && expiration == NOEXP) {
+		if (expires) {
+		    expiration = expires->ivalue;
+		} else if (regc->expires_hdr) {
+		    expiration = regc->expires_hdr->ivalue;
+		} else {
+		    /* We didn't request explicit expiration value,
+		     * and server doesn't specify it either. This 
+		     * shouldn't happen unless we have a broken
+		     * registrar.
+		     */
+		    expiration = 3600;
+		}
+	    }
+
+	}
+
+	/* If we still couldn't get matching Contact header(s), it means
+	 * there must be something wrong with the  registrar (e.g. it may
+	 * have modified the URI's in the response, which is prohibited).
+	 */
+	if (expiration==NOEXP) {
+	    /* If the number of Contact headers in the response matches 
+	     * ours, they're all probably ours. Get the expiration
+	     * from there if this is the case, or from Expires header
+	     * if we don't have exact Contact header count, or
+	     * from the request as the last resort.
+	     */
+	    unsigned our_contact_cnt;
+
+	    our_contact_cnt = pj_list_size(&regc->contact_hdr_list);
+
+	    if (*contact_cnt == our_contact_cnt && *contact_cnt &&
+		contacts[0]->expires >= 0) 
+	    {
+		expiration = contacts[0]->expires;
+	    } else if (expires)
+		expiration = expires->ivalue;
+	    else if (regc->expires_hdr)
+		expiration = regc->expires_hdr->ivalue;
+	    else
+		expiration = 3600;
+	}
+
+    } else {
+	/* Just assume that the unregistration has been successful. */
+	expiration = 0;
+    }
+
+    /* Must have expiration value by now */
+    pj_assert(expiration != NOEXP);
+
+    return expiration;
+}
+
+static void regc_tsx_callback(void *token, pjsip_event *event)
+{
+    pj_status_t status;
+    pjsip_regc *regc = (pjsip_regc*) token;
+    pjsip_transaction *tsx = event->body.tsx_state.tsx;
+    pj_bool_t handled = PJ_TRUE;
+
+    pj_atomic_inc(regc->busy_ctr);
+    pj_lock_acquire(regc->lock);
+
+    /* Decrement pending transaction counter. */
+    pj_assert(regc->has_tsx);
+    regc->has_tsx = PJ_FALSE;
+
+    /* Add reference to the transport */
+    if (tsx->transport != regc->last_transport) {
+	if (regc->last_transport) {
+	    pjsip_transport_dec_ref(regc->last_transport);
+	    regc->last_transport = NULL;
+	}
+
+	if (tsx->transport) {
+	    regc->last_transport = tsx->transport;
+	    pjsip_transport_add_ref(regc->last_transport);
+	}
+    }
+
+    /* Handle 401/407 challenge (even when _delete_flag is set) */
+    if (tsx->status_code == PJSIP_SC_PROXY_AUTHENTICATION_REQUIRED ||
+	tsx->status_code == PJSIP_SC_UNAUTHORIZED)
+    {
+	pjsip_rx_data *rdata = event->body.tsx_state.src.rdata;
+	pjsip_tx_data *tdata;
+
+	/* reset current op */
+	regc->current_op = REGC_IDLE;
+
+	status = pjsip_auth_clt_reinit_req( &regc->auth_sess,
+					    rdata, 
+					    tsx->last_tx,  
+					    &tdata);
+
+	if (status == PJ_SUCCESS) {
+	    status = pjsip_regc_send(regc, tdata);
+	}
+	
+	if (status != PJ_SUCCESS) {
+
+	    /* Only call callback if application is still interested
+	     * in it.
+	     */
+	    if (regc->_delete_flag == 0) {
+		/* Should be safe to release the lock temporarily.
+		 * We do this to avoid deadlock. 
+		 */
+		pj_lock_release(regc->lock);
+		call_callback(regc, status, tsx->status_code, 
+			      &rdata->msg_info.msg->line.status.reason,
+			      rdata, -1, 0, NULL);
+		pj_lock_acquire(regc->lock);
+	    }
+	}
+
+    } else if (regc->_delete_flag) {
+
+	/* User has called pjsip_regc_destroy(), so don't call callback. 
+	 * This regc will be destroyed later in this function.
+	 */
+
+	/* Just reset current op */
+	regc->current_op = REGC_IDLE;
+
+    } else if (tsx->status_code == PJSIP_SC_INTERVAL_TOO_BRIEF &&
+	       regc->current_op == REGC_REGISTERING)
+    {
+	/* Handle 423 response automatically:
+	 *  - set requested expiration to Min-Expires header, ONLY IF
+	 *    the original request is a registration (as opposed to
+	 *    unregistration) and the requested expiration was indeed
+	 *    lower than Min-Expires)
+	 *  - resend the request
+	 */
+	pjsip_rx_data *rdata = event->body.tsx_state.src.rdata;
+	pjsip_min_expires_hdr *me_hdr;
+	pjsip_tx_data *tdata;
+	pj_int32_t min_exp;
+
+	/* reset current op */
+	regc->current_op = REGC_IDLE;
+
+	/* Update requested expiration */
+	me_hdr = (pjsip_min_expires_hdr*)
+		 pjsip_msg_find_hdr(rdata->msg_info.msg,
+				    PJSIP_H_MIN_EXPIRES, NULL);
+	if (me_hdr) {
+	    min_exp = me_hdr->ivalue;
+	} else {
+	    /* Broken server, Min-Expires doesn't exist.
+	     * Just guestimate then, BUT ONLY if if this is the
+	     * first time we received such response.
+	     */
+	    enum {
+		/* Note: changing this value would require changing couple of
+		 *       Python test scripts.
+		 */
+		UNSPECIFIED_MIN_EXPIRES = 3601
+	    };
+	    if (!regc->expires_hdr ||
+		 regc->expires_hdr->ivalue != UNSPECIFIED_MIN_EXPIRES)
+	    {
+		min_exp = UNSPECIFIED_MIN_EXPIRES;
+	    } else {
+		handled = PJ_FALSE;
+		PJ_LOG(4,(THIS_FILE, "Registration failed: 423 response "
+				     "without Min-Expires header is invalid"));
+		goto handle_err;
+	    }
+	}
+
+	if (regc->expires_hdr && regc->expires_hdr->ivalue >= min_exp) {
+	    /* But we already send with greater expiration time, why does
+	     * the server send us with 423? Oh well, just fail the request.
+	     */
+	    handled = PJ_FALSE;
+	    PJ_LOG(4,(THIS_FILE, "Registration failed: invalid "
+			         "Min-Expires header value in response"));
+	    goto handle_err;
+	}
+
+	set_expires(regc, min_exp);
+
+	status = pjsip_regc_register(regc, regc->auto_reg, &tdata);
+	if (status == PJ_SUCCESS) {
+	    status = pjsip_regc_send(regc, tdata);
+	}
+
+	if (status != PJ_SUCCESS) {
+	    /* Only call callback if application is still interested
+	     * in it.
+	     */
+	    if (!regc->_delete_flag) {
+		/* Should be safe to release the lock temporarily.
+		 * We do this to avoid deadlock.
+		 */
+		pj_lock_release(regc->lock);
+		call_callback(regc, status, tsx->status_code,
+			      &rdata->msg_info.msg->line.status.reason,
+			      rdata, -1, 0, NULL);
+		pj_lock_acquire(regc->lock);
+	    }
+	}
+
+    } else {
+	handled = PJ_FALSE;
+    }
+
+handle_err:
+    if (!handled) {
+	pjsip_rx_data *rdata;
+	pj_int32_t expiration = NOEXP;
+	unsigned contact_cnt = 0;
+	pjsip_contact_hdr *contact[PJSIP_REGC_MAX_CONTACT];
+
+	if (tsx->status_code/100 == 2) {
+
+	    rdata = event->body.tsx_state.src.rdata;
+
+	    /* Calculate expiration */
+	    expiration = calculate_response_expiration(regc, rdata, 
+						       &contact_cnt,
+						       PJSIP_REGC_MAX_CONTACT,
+						       contact);
+
+	    /* Schedule next registration */
+            schedule_registration(regc, expiration);
+
+	} else {
+	    rdata = (event->body.tsx_state.type==PJSIP_EVENT_RX_MSG) ? 
+			event->body.tsx_state.src.rdata : NULL;
+	}
+
+	/* Update registration */
+	if (expiration==NOEXP) expiration=-1;
+	regc->expires = expiration;
+
+	/* Mark operation as complete */
+	regc->current_op = REGC_IDLE;
+
+	/* Call callback. */
+	/* Should be safe to release the lock temporarily.
+	 * We do this to avoid deadlock. 
+	 */
+	pj_lock_release(regc->lock);
+	call_callback(regc, PJ_SUCCESS, tsx->status_code, 
+		      (rdata ? &rdata->msg_info.msg->line.status.reason 
+			: &tsx->status_text),
+		      rdata, expiration, 
+		      contact_cnt, contact);
+	pj_lock_acquire(regc->lock);
+    }
+
+    pj_lock_release(regc->lock);
+
+    /* Delete the record if user destroy regc during the callback. */
+    if (pj_atomic_dec_and_get(regc->busy_ctr)==0 && regc->_delete_flag) {
+	pjsip_regc_destroy(regc);
+    }
+}
+
+PJ_DEF(pj_status_t) pjsip_regc_send(pjsip_regc *regc, pjsip_tx_data *tdata)
+{
+    pj_status_t status;
+    pjsip_cseq_hdr *cseq_hdr;
+    pjsip_expires_hdr *expires_hdr;
+    pj_uint32_t cseq;
+
+    pj_atomic_inc(regc->busy_ctr);
+    pj_lock_acquire(regc->lock);
+
+    /* Make sure we don't have pending transaction. */
+    if (regc->has_tsx) {
+	PJ_LOG(4,(THIS_FILE, "Unable to send request, regc has another "
+			     "transaction pending"));
+	pjsip_tx_data_dec_ref( tdata );
+	pj_lock_release(regc->lock);
+	pj_atomic_dec(regc->busy_ctr);
+	return PJSIP_EBUSY;
+    }
+
+    pj_assert(regc->current_op == REGC_IDLE);
+
+    /* Invalidate message buffer. */
+    pjsip_tx_data_invalidate_msg(tdata);
+
+    /* Increment CSeq */
+    cseq = ++regc->cseq_hdr->cseq;
+    cseq_hdr = (pjsip_cseq_hdr*)
+	       pjsip_msg_find_hdr(tdata->msg, PJSIP_H_CSEQ, NULL);
+    cseq_hdr->cseq = cseq;
+
+    /* Find Expires header */
+    expires_hdr = (pjsip_expires_hdr*)
+		  pjsip_msg_find_hdr(tdata->msg, PJSIP_H_EXPIRES, NULL);
+
+    /* Bind to transport selector */
+    pjsip_tx_data_set_transport(tdata, &regc->tp_sel);
+
+    regc->has_tsx = PJ_TRUE;
+
+    /* Set current operation based on the value of Expires header */
+    if (expires_hdr && expires_hdr->ivalue==0)
+	regc->current_op = REGC_UNREGISTERING;
+    else
+	regc->current_op = REGC_REGISTERING;
+
+    /* Prevent deletion of tdata, e.g: when something wrong in sending,
+     * we need tdata to retrieve the transport.
+     */
+    pjsip_tx_data_add_ref(tdata);
+
+    /* If via_addr is set, use this address for the Via header. */
+    if (regc->via_addr.host.slen > 0) {
+        tdata->via_addr = regc->via_addr;
+        tdata->via_tp = regc->via_tp;
+    }
+
+    /* Need to unlock the regc temporarily while sending the message to
+     * prevent deadlock (https://trac.pjsip.org/repos/ticket/1247).
+     * It should be safe to do this since the regc's refcount has been
+     * incremented.
+     */
+    pj_lock_release(regc->lock);
+
+    /* Now send the message */
+    status = pjsip_endpt_send_request(regc->endpt, tdata, REGC_TSX_TIMEOUT,
+				      regc, &regc_tsx_callback);
+    if (status!=PJ_SUCCESS) {
+	PJ_LOG(4,(THIS_FILE, "Error sending request, status=%d", status));
+    }
+
+    /* Reacquire the lock */
+    pj_lock_acquire(regc->lock);
+
+    /* Get last transport used and add reference to it */
+    if (tdata->tp_info.transport != regc->last_transport &&
+	status==PJ_SUCCESS)
+    {
+	if (regc->last_transport) {
+	    pjsip_transport_dec_ref(regc->last_transport);
+	    regc->last_transport = NULL;
+	}
+
+	if (tdata->tp_info.transport) {
+	    regc->last_transport = tdata->tp_info.transport;
+	    pjsip_transport_add_ref(regc->last_transport);
+	}
+    }
+
+    /* Release tdata */
+    pjsip_tx_data_dec_ref(tdata);
+
+    pj_lock_release(regc->lock);
+
+    /* Delete the record if user destroy regc during the callback. */
+    if (pj_atomic_dec_and_get(regc->busy_ctr)==0 && regc->_delete_flag) {
+	pjsip_regc_destroy(regc);
+    }
+
+    return status;
+}
+
+