res_pjsip_refer.c File Reference

#include "asterisk.h"
#include <pjsip.h>
#include <pjsip_ua.h>
#include "asterisk/res_pjsip.h"
#include "asterisk/res_pjsip_session.h"
#include "asterisk/module.h"
#include "asterisk/pbx.h"
#include "asterisk/taskprocessor.h"
#include "asterisk/bridge.h"
#include "asterisk/framehook.h"
#include "asterisk/stasis_bridges.h"
#include "asterisk/stasis_channels.h"
#include "asterisk/causes.h"
#include "asterisk/refer.h"

Include dependency graph for res_pjsip_refer.c:

Go to the source code of this file.

Data Structures
struct	invite_replaces
	Structure used to retrieve channel from another session. More...
struct	refer_attended
	Structure for attended transfer task. More...
struct	refer_blind
	Structure for blind transfer callback details. More...
struct	refer_data
struct	refer_out_of_dialog
struct	refer_progress
	REFER Progress structure. More...
struct	refer_progress_notification
	REFER Progress notification structure. More...

Macros
#define	DETERMINE_TRANSFER_CONTEXT(context, session)

Functions
static void	__reg_module (void)
static void	__unreg_module (void)
static void	add_header_from_channel_var (struct ast_channel *chan, const char *var_name, const char *header_name, pjsip_tx_data *tdata)
	Use the value of a channel variable as the value of a SIP header. More...
struct ast_module *	AST_MODULE_SELF_SYM (void)
static int	defer_termination_cancel_task (void *data)
static int	dlg_releaser_task (void *data)
static pjsip_uri *	get_refer_to_uri (pjsip_tx_data *tdata)
	Helper function which returns the name-addr of the Refer-To header or NULL. More...
static int	invite_replaces (void *data)
	Task for invite replaces. More...
static int	is_refer_var_blocked (const char *name)
static int	load_module (void)
static struct refer_attended *	refer_attended_alloc (struct ast_sip_session *transferer, struct ast_sip_session *transferer_second, struct refer_progress *progress)
	Allocator for attended transfer task. More...
static void	refer_attended_destroy (void *obj)
	Destructor for attended transfer task. More...
static int	refer_attended_task (void *data)
	Task for attended transfer executed by attended->transferer_second serializer. More...
static void	refer_blind_callback (struct ast_channel *chan, struct transfer_channel_data *user_data_wrapper, enum ast_transfer_type transfer_type)
	Blind transfer callback function. More...
static void	refer_client_on_evsub_state (pjsip_evsub *sub, pjsip_event *event)
static struct refer_data *	refer_data_create (const struct ast_refer *refer)
static void	refer_data_destroy (void *obj)
static int	refer_incoming_attended_request (struct ast_sip_session *session, pjsip_rx_data *rdata, pjsip_sip_uri *target_uri, pjsip_param *replaces_param, struct refer_progress *progress)
static int	refer_incoming_blind_request (struct ast_sip_session *session, pjsip_rx_data *rdata, pjsip_sip_uri *target, struct refer_progress *progress)
static int	refer_incoming_invite_request (struct ast_sip_session *session, struct pjsip_rx_data *rdata)
static int	refer_incoming_refer_request (struct ast_sip_session *session, struct pjsip_rx_data *rdata)
static int	refer_incoming_request (struct ast_sip_session *session, pjsip_rx_data *rdata)
static pj_status_t	refer_on_tx_request (pjsip_tx_data *tdata)
static void	refer_out_of_dialog_destroy (void *obj)
	Destructor for REFER out of dialog structure. More...
static void	refer_outgoing_request (struct ast_sip_session *session, struct pjsip_tx_data *tdata)
static int	refer_progress_alloc (struct ast_sip_session *session, pjsip_rx_data *rdata, struct refer_progress **progress)
	Internal helper function which sets up a refer progress structure if needed. More...
static void	refer_progress_bridge (void *data, struct stasis_subscription *sub, struct stasis_message *message)
static void	refer_progress_destroy (void *obj)
	Destructor for REFER progress sutrcture. More...
static struct ast_frame *	refer_progress_framehook (struct ast_channel *chan, struct ast_frame *f, enum ast_framehook_event event, void *data)
	Progress monitoring frame hook - examines frames to determine state of transfer. More...
static void	refer_progress_framehook_destroy (void *data)
	Destroy callback for monitoring framehook. More...
static struct refer_progress_notification *	refer_progress_notification_alloc (struct refer_progress *progress, int response, pjsip_evsub_state state)
	Allocator for REFER Progress notification structure. More...
static void	refer_progress_notification_destroy (void *obj)
	Destructor for REFER Progress notification structure. More...
static int	refer_progress_notify (void *data)
	Serialized callback for subscription notification. More...
static void	refer_progress_on_evsub_state (pjsip_evsub *sub, pjsip_event *event)
	Callback for REFER subscription state changes. More...
static int	refer_send (void *data)
static int	refer_unreference_dialog (void *obj)
static int	session_end_if_deferred_task (void *data)
static int	sip_refer_send (const struct ast_refer *refer)
static int	unload_module (void)
static enum pjsip_status_code	vars_to_headers (const struct ast_refer *refer, pjsip_tx_data *tdata)
static int	xfer_response_code2sip (enum ast_transfer_result xfer_code)

Variables
static struct ast_module_info	__mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "PJSIP Blind and Attended Transfer Support" , .key = "This paragraph is copyright (c) 2006 by Digium, Inc. \In order for your module to load, it must return this \key via a function called \"key\". Any code which \includes this paragraph must be licensed under the GNU \General Public License version 2 or later (at your \option). In addition to Digium's general reservations \of rights, Digium expressly reserves the right to \allow other parties to license this paragraph under \different terms. Any use of Digium, Inc. trademarks or \logos (including \"Asterisk\" or \"Digium\") without \express written permission of Digium, Inc. is prohibited.\n" , .buildopt_sum = AST_BUILDOPT_SUM, .support_level = AST_MODULE_SUPPORT_CORE, .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_APP_DEPEND, .requires = "res_pjsip,res_pjsip_session,res_pjsip_pubsub", }
static const struct ast_module_info *	ast_module_info = &__mod_info
static pjsip_module	refer_out_of_dialog_module
	REFER Out-of-dialog module, used to attach session data structure to subscription. More...
static pjsip_evsub_user	refer_progress_evsub_cb
	Callback structure for subscription. More...
static pjsip_module	refer_progress_module
	REFER Progress module, used to attach REFER progress structure to subscriptions. More...
static struct ast_taskprocessor *	refer_serializer
static struct ast_sip_session_supplement	refer_supplement
static const struct ast_refer_tech	refer_tech

Macro Definition Documentation

DETERMINE_TRANSFER_CONTEXT

#define DETERMINE_TRANSFER_CONTEXT	(		context,
			session
	)

Definition at line 837 of file res_pjsip_refer.c.

Function Documentation

__reg_module()

static void __reg_module ( void  )

static

Definition at line 1865 of file res_pjsip_refer.c.

__unreg_module()

static void __unreg_module ( void  )

static

Definition at line 1865 of file res_pjsip_refer.c.

add_header_from_channel_var()

static void add_header_from_channel_var ( struct ast_channel *  chan, const char *  var_name, const char *  header_name, pjsip_tx_data *  tdata  )

static

Use the value of a channel variable as the value of a SIP header.

This looks up a variable name on a channel, then takes that value and adds it to an outgoing SIP request. If the header already exists on the message, then no action is taken.

Precondition

chan is locked.

Parameters

chan	The channel on which to find the variable.
var_name	The name of the channel variable to use.
header_name	The name of the SIP header to add to the outgoing message.
tdata	The outgoing SIP message on which to add the header

Definition at line 1780 of file res_pjsip_refer.c.

{
    const char *var_value;
    pj_str_t pj_header_name;
    pjsip_hdr *header;
 
    var_value = pbx_builtin_getvar_helper(chan, var_name);
    if (ast_strlen_zero(var_value)) {
        return;
    }
 
    pj_cstr(&pj_header_name, header_name);
    header = pjsip_msg_find_hdr_by_name(tdata->msg, &pj_header_name, NULL);
    if (header) {
        return;
    }
    ast_sip_add_header(tdata, header_name, var_value);
}

References ast_sip_add_header(), ast_strlen_zero(), NULL, and pbx_builtin_getvar_helper().

Referenced by refer_outgoing_request().

AST_MODULE_SELF_SYM()

struct ast_module * AST_MODULE_SELF_SYM

(

void

)

Definition at line 1865 of file res_pjsip_refer.c.

defer_termination_cancel_task()

static int defer_termination_cancel_task ( void *  data )

static

Definition at line 516 of file res_pjsip_refer.c.

{
    struct ast_sip_session *session = data;
 
    ast_sip_session_end_if_deferred(session);
    ast_sip_session_defer_termination_cancel(session);
    ao2_ref(session, -1);
    return 0;
}

References ao2_ref, ast_sip_session_defer_termination_cancel(), ast_sip_session_end_if_deferred(), and session.

Referenced by refer_attended_task().

dlg_releaser_task()

static int dlg_releaser_task ( void *  data )

static

Definition at line 348 of file res_pjsip_refer.c.

                                         {
    pjsip_dlg_dec_session((pjsip_dialog *)data, &refer_progress_module);
    return 0;
}

References refer_progress_module.

Referenced by refer_progress_destroy().

get_refer_to_uri()

static pjsip_uri * get_refer_to_uri ( pjsip_tx_data *  tdata )

static

Helper function which returns the name-addr of the Refer-To header or NULL.

Definition at line 1000 of file res_pjsip_refer.c.

{
    const pj_str_t REFER_TO = { "Refer-To", 8 };
    pjsip_generic_string_hdr *refer_to;
    pjsip_uri *parsed_uri;
 
    if (!(refer_to = pjsip_msg_find_hdr_by_name(tdata->msg, &REFER_TO, NULL))
        || !(parsed_uri = pjsip_parse_uri(tdata->pool, refer_to->hvalue.ptr, refer_to->hvalue.slen, 0))
        || (!PJSIP_URI_SCHEME_IS_SIP(parsed_uri) && !PJSIP_URI_SCHEME_IS_SIPS(parsed_uri))) {
        return NULL;
    }
 
    return parsed_uri;
}

References NULL.

Referenced by refer_on_tx_request().

invite_replaces()

static int invite_replaces ( void *  data )

static

Task for invite replaces.

Definition at line 1507 of file res_pjsip_refer.c.

{
    struct invite_replaces *invite = data;
 
    if (!invite->session->channel) {
        return -1;
    }
 
    ast_channel_ref(invite->session->channel);
    invite->channel = invite->session->channel;
 
    invite->bridge = ast_bridge_transfer_acquire_bridge(invite->channel);
    return 0;
}

References ast_bridge_transfer_acquire_bridge(), ast_channel_ref, invite_replaces::bridge, ast_sip_session::channel, invite_replaces::channel, and invite_replaces::session.

is_refer_var_blocked()

static int is_refer_var_blocked ( const char *  name )

static

Definition at line 932 of file res_pjsip_refer.c.

{
    int i;
 
    /* Don't block the Max-Forwards header because the user can override it */
    static const char *hdr[] = {
        "To",
        "From",
        "Via",
        "Route",
        "Contact",
        "Call-ID",
        "CSeq",
        "Allow",
        "Content-Length",
        "Content-Type",
        "Request-URI",
    };
 
    for (i = 0; i < ARRAY_LEN(hdr); ++i) {
        if (!strcasecmp(name, hdr[i])) {
            /* Block addition of this header. */
            return 1;
        }
    }
    return 0;
}

References ARRAY_LEN, and name.

Referenced by vars_to_headers().

load_module()

static int load_module ( void  )

static

Definition at line 1819 of file res_pjsip_refer.c.

{
    const pj_str_t str_norefersub = { "norefersub", 10 };
 
    pjsip_replaces_init_module(ast_sip_get_pjsip_endpoint());
    pjsip_xfer_init_module(ast_sip_get_pjsip_endpoint());
 
    if (ast_sip_get_norefersub()) {
        pjsip_endpt_add_capability(ast_sip_get_pjsip_endpoint(), NULL, PJSIP_H_SUPPORTED, NULL, 1, &str_norefersub);
    }
 
    if (ast_refer_tech_register(&refer_tech)) {
        return AST_MODULE_LOAD_DECLINE;
    }
 
    refer_serializer = ast_sip_create_serializer("pjsip/refer");
    if (!refer_serializer) {
        ast_refer_tech_unregister(&refer_tech);
        return AST_MODULE_LOAD_DECLINE;
    }
 
    ast_sip_register_service(&refer_out_of_dialog_module);
    ast_sip_register_service(&refer_progress_module);
    ast_sip_session_register_supplement(&refer_supplement);
 
    ast_module_shutdown_ref(ast_module_info->self);
 
    return AST_MODULE_LOAD_SUCCESS;
}

References AST_MODULE_LOAD_DECLINE, AST_MODULE_LOAD_SUCCESS, ast_module_shutdown_ref, ast_refer_tech_register(), ast_refer_tech_unregister(), ast_sip_create_serializer(), ast_sip_get_norefersub(), ast_sip_get_pjsip_endpoint(), ast_sip_register_service(), ast_sip_session_register_supplement, NULL, refer_out_of_dialog_module, refer_progress_module, refer_serializer, refer_supplement, refer_tech, and ast_module_info::self.

refer_attended_alloc()

static struct refer_attended * refer_attended_alloc ( struct ast_sip_session *  transferer, struct ast_sip_session *  transferer_second, struct refer_progress *  progress  )

static

Allocator for attended transfer task.

Definition at line 480 of file res_pjsip_refer.c.

{
    struct refer_attended *attended;
 
    attended = ao2_alloc_options(sizeof(*attended), refer_attended_destroy,
        AO2_ALLOC_OPT_LOCK_NOLOCK);
    if (!attended) {
        return NULL;
    }
 
    ao2_ref(transferer, +1);
    attended->transferer = transferer;
    ast_channel_ref(transferer->channel);
    attended->transferer_chan = transferer->channel;
    ao2_ref(transferer_second, +1);
    attended->transferer_second = transferer_second;
 
    if (progress) {
        ao2_ref(progress, +1);
        attended->progress = progress;
    }
 
    return attended;
}

References AO2_ALLOC_OPT_LOCK_NOLOCK, ao2_alloc_options, ao2_ref, ast_channel_ref, ast_sip_session::channel, NULL, refer_attended::progress, refer_attended_destroy(), refer_attended::transferer, refer_attended::transferer_chan, and refer_attended::transferer_second.

Referenced by refer_incoming_attended_request().

refer_attended_destroy()

static void refer_attended_destroy ( void *  obj )

static

Destructor for attended transfer task.

Definition at line 469 of file res_pjsip_refer.c.

{
    struct refer_attended *attended = obj;
 
    ao2_cleanup(attended->transferer);
    ast_channel_cleanup(attended->transferer_chan);
    ao2_cleanup(attended->transferer_second);
    ao2_cleanup(attended->progress);
}

References ao2_cleanup, ast_channel_cleanup, refer_attended::progress, refer_attended::transferer, refer_attended::transferer_chan, and refer_attended::transferer_second.

Referenced by refer_attended_alloc().

refer_attended_task()

static int refer_attended_task ( void *  data )

static

Task for attended transfer executed by attended->transferer_second serializer.

Definition at line 558 of file res_pjsip_refer.c.

{
    struct refer_attended *attended = data;
    int response;
    int (*task_cb)(void *data);
 
    if (attended->transferer_second->channel) {
        ast_debug(3, "Performing a REFER attended transfer - Transferer #1: %s Transferer #2: %s\n",
            ast_channel_name(attended->transferer_chan),
            ast_channel_name(attended->transferer_second->channel));
 
        response = xfer_response_code2sip(ast_bridge_transfer_attended(
            attended->transferer_chan,
            attended->transferer_second->channel));
 
        ast_debug(3, "Final response for REFER attended transfer - Transferer #1: %s Transferer #2: %s is '%d'\n",
            ast_channel_name(attended->transferer_chan),
            ast_channel_name(attended->transferer_second->channel),
            response);
    } else {
        ast_debug(3, "Received REFER request on channel '%s' but other channel has gone.\n",
            ast_channel_name(attended->transferer_chan));
        response = 603;
    }
 
    if (attended->progress) {
        struct refer_progress_notification *notification;
 
        notification = refer_progress_notification_alloc(attended->progress, response,
            PJSIP_EVSUB_STATE_TERMINATED);
        if (notification) {
            if (ast_sip_push_task(attended->progress->serializer, refer_progress_notify, notification)) {
                ao2_cleanup(notification);
            }
        }
    }
 
    if (response == 200) {
        task_cb = session_end_if_deferred_task;
    } else {
        task_cb = defer_termination_cancel_task;
    }
    if (!ast_sip_push_task(attended->transferer->serializer,
        task_cb, attended->transferer)) {
        /* Gave the ref to the pushed task. */
        attended->transferer = NULL;
    } else {
        /* Do this anyway even though it is the wrong serializer. */
        ast_sip_session_end_if_deferred(attended->transferer);
    }
 
    ao2_ref(attended, -1);
    return 0;
}

References ao2_cleanup, ao2_ref, ast_bridge_transfer_attended(), ast_channel_name(), ast_debug, ast_sip_push_task(), ast_sip_session_end_if_deferred(), ast_sip_session::channel, defer_termination_cancel_task(), NULL, refer_attended::progress, refer_progress_notification_alloc(), refer_progress_notify(), refer_progress_notification::response, ast_sip_session::serializer, refer_progress::serializer, session_end_if_deferred_task(), refer_attended::transferer, refer_attended::transferer_chan, refer_attended::transferer_second, and xfer_response_code2sip().

Referenced by refer_incoming_attended_request().

refer_blind_callback()

static void refer_blind_callback ( struct ast_channel *  chan, struct transfer_channel_data *  user_data_wrapper, enum ast_transfer_type  transfer_type  )

static

Blind transfer callback function.

Definition at line 630 of file res_pjsip_refer.c.

{
    struct refer_blind *refer = user_data_wrapper->data;
    pjsip_generic_string_hdr *referred_by;
 
    static const pj_str_t str_referred_by = { "Referred-By", 11 };
    static const pj_str_t str_referred_by_s = { "b", 1 };
    const char *get_xfrdata;
 
    pbx_builtin_setvar_helper(chan, "SIPTRANSFER", "yes");
 
    if (refer->progress && !refer->attended && !refer->progress->refer_blind_progress) {
        /* If blind transfer and endpoint doesn't want to receive all the progress details */
        struct refer_progress_notification *notification = refer_progress_notification_alloc(refer->progress, 200,
            PJSIP_EVSUB_STATE_TERMINATED);
 
        if (notification) {
            if (ast_sip_push_task(refer->progress->serializer, refer_progress_notify, notification)) {
                ao2_cleanup(notification);
            }
        }
    } else if (refer->progress) {
        /* If attended transfer and progress monitoring is being done attach a frame hook so we can monitor it */
        struct ast_framehook_interface hook = {
            .version = AST_FRAMEHOOK_INTERFACE_VERSION,
            .event_cb = refer_progress_framehook,
            .destroy_cb = refer_progress_framehook_destroy,
            .data = refer->progress,
            .disable_inheritance = 1,
        };
 
        refer->progress->transferee = ast_strdup(ast_channel_uniqueid(chan));
        if (!refer->progress->transferee) {
            struct refer_progress_notification *notification = refer_progress_notification_alloc(refer->progress, 200,
                PJSIP_EVSUB_STATE_TERMINATED);
 
            ast_log(LOG_WARNING, "Could not copy channel name '%s' during transfer - assuming success\n",
                ast_channel_name(chan));
 
            if (notification) {
                if (ast_sip_push_task(refer->progress->serializer, refer_progress_notify, notification)) {
                    ao2_cleanup(notification);
                }
            }
        }
 
        /* Progress needs a reference to the transfer_channel_data so that it can track the completed status of the transfer */
        ao2_ref(user_data_wrapper, +1);
        refer->progress->transfer_data = user_data_wrapper;
 
        /* We need to bump the reference count up on the progress structure since it is in the frame hook now */
        ao2_ref(refer->progress, +1);
 
        /* If we can't attach a frame hook for whatever reason send a notification of success immediately */
        ast_channel_lock(chan);
        refer->progress->framehook = ast_framehook_attach(chan, &hook);
        ast_channel_unlock(chan);
        if (refer->progress->framehook < 0) {
            struct refer_progress_notification *notification = refer_progress_notification_alloc(refer->progress, 200,
                PJSIP_EVSUB_STATE_TERMINATED);
 
            ast_log(LOG_WARNING, "Could not attach REFER transfer progress monitoring hook to channel '%s' - assuming success\n",
                ast_channel_name(chan));
 
            if (notification) {
                if (ast_sip_push_task(refer->progress->serializer, refer_progress_notify, notification)) {
                    ao2_cleanup(notification);
                }
            }
 
            ao2_cleanup(refer->progress);
        }
 
        /* We need to bump the reference count for the stasis subscription */
        ao2_ref(refer->progress, +1);
        /* We also will need to detect if the transferee enters a bridge. This is currently the only reliable way to
         * detect if the transfer target has answered the call
         */
        refer->progress->bridge_sub = stasis_subscribe_pool(ast_bridge_topic_all(), refer_progress_bridge, refer->progress);
        if (!refer->progress->bridge_sub) {
            struct refer_progress_notification *notification = refer_progress_notification_alloc(refer->progress, 200,
                PJSIP_EVSUB_STATE_TERMINATED);
 
            ast_log(LOG_WARNING, "Could not create bridge stasis subscription for monitoring progress on transfer of channel '%s' - assuming success\n",
                    ast_channel_name(chan));
 
            if (notification) {
                if (ast_sip_push_task(refer->progress->serializer, refer_progress_notify, notification)) {
                    ao2_cleanup(notification);
                }
            }
 
            ast_channel_lock(chan);
            ast_framehook_detach(chan, refer->progress->framehook);
            ast_channel_unlock(chan);
 
            ao2_cleanup(refer->progress);
        } else {
            stasis_subscription_accept_message_type(refer->progress->bridge_sub, ast_channel_entered_bridge_type());
            stasis_subscription_accept_message_type(refer->progress->bridge_sub, stasis_subscription_change_type());
            stasis_subscription_set_filter(refer->progress->bridge_sub, STASIS_SUBSCRIPTION_FILTER_SELECTIVE);
        }
    }
 
    pbx_builtin_setvar_helper(chan, "SIPREFERRINGCONTEXT", S_OR(refer->context, NULL));
 
    ast_channel_lock(chan);
    if ((get_xfrdata = pbx_builtin_getvar_helper(chan, "GET_TRANSFERRER_DATA"))) {
        get_xfrdata = ast_strdupa(get_xfrdata);
    }
    ast_channel_unlock(chan);
    if (!ast_strlen_zero(get_xfrdata)) {
        const pjsip_msg * msg = refer->rdata->msg_info.msg;
        const struct pjsip_hdr *end = &msg->hdr;
        struct pjsip_hdr *hdr = end->next;
        struct ast_str *pbxvar = ast_str_create(64); /* initial buffer for variable name, extended on demand */
        char buf[4096]; /* should be enough for one header value */
        const char *prefix = get_xfrdata;
 
        /* The '*' alone matches all headers. */
        if (!strcmp(prefix, "*")) {
            prefix = "";
        }
        if (pbxvar) {
            for (; hdr != end; hdr = hdr->next) {
                if (!pj_strnicmp2(&hdr->name, prefix, strlen(prefix))) {
                    const int hdr_name_strlen = pj_strlen(&hdr->name);
                    const int hdr_name_bytes = hdr_name_strlen + 1; /* +1 for string NULL terminator */
                    char hdr_name[hdr_name_bytes];
                    int len;
                    char *value_str;
 
                    ast_copy_pj_str(hdr_name, &hdr->name, hdr_name_bytes);
                    len = pjsip_hdr_print_on(hdr, buf, sizeof(buf) - 1);
                    if (len < 0) {
                        /* ignore too long headers */
                        ast_log(LOG_WARNING, "Could not store header '%s' from transfer on channel '%s' - too long text\n", hdr_name, ast_channel_name(chan));
                        continue;
                    }
                    buf[len] = '\0';
 
                    /* Get value - remove header name (before ':') from buf and trim blanks. */
                    value_str = strchr(buf, ':');
                    if (!value_str) {
                        /* Ignore header without value */
                        continue;
                    }
                    value_str = ast_strip(value_str + 1); /* +1 to get string right after the ':' delimiter (i.e. header value) */
                    
                    ast_str_set(&pbxvar, -1, "~HASH~TRANSFER_DATA~%.*s~", hdr_name_strlen, hdr_name);
                    pbx_builtin_setvar_helper(chan, ast_str_buffer(pbxvar), value_str);
                    ast_debug(5, "On channel '%s' set TRANSFER_DATA variable '%s' to value '%s' \n", ast_channel_name(chan), hdr_name, value_str);
                }
            }
            ast_free(pbxvar);
        } else {
            ast_log(LOG_ERROR, "Channel '%s' failed to allocate buffer for TRANSFER_DATA variable\n", ast_channel_name(chan));
        }
    }
 
    referred_by = pjsip_msg_find_hdr_by_names(refer->rdata->msg_info.msg,
        &str_referred_by, &str_referred_by_s, NULL);
    if (referred_by) {
        size_t uri_size = pj_strlen(&referred_by->hvalue) + 1;
        char *uri = ast_alloca(uri_size);
 
        ast_copy_pj_str(uri, &referred_by->hvalue, uri_size);
        pbx_builtin_setvar_helper(chan, "__SIPREFERREDBYHDR", S_OR(uri, NULL));
    } else {
        pbx_builtin_setvar_helper(chan, "SIPREFERREDBYHDR", NULL);
    }
 
    if (refer->replaces) {
        char replaces[512];
        char *replaces_val = NULL;
        int len;
 
        len = pjsip_hdr_print_on(refer->replaces, replaces, sizeof(replaces) - 1);
        if (len != -1) {
            /* pjsip_hdr_print_on does not NULL terminate the buffer */
            replaces[len] = '\0';
            replaces_val = replaces + sizeof("Replaces:");
        }
        pbx_builtin_setvar_helper(chan, "__SIPREPLACESHDR", replaces_val);
    } else {
        pbx_builtin_setvar_helper(chan, "SIPREPLACESHDR", NULL);
    }
 
    if (refer->refer_to) {
        char refer_to[PJSIP_MAX_URL_SIZE];
 
        pjsip_uri_print(PJSIP_URI_IN_REQ_URI, refer->refer_to, refer_to, sizeof(refer_to));
        pbx_builtin_setvar_helper(chan, "SIPREFERTOHDR", S_OR(refer_to, NULL));
    } else {
        pbx_builtin_setvar_helper(chan, "SIPREFERTOHDR", NULL);
    }
}

References ao2_cleanup, ao2_ref, ast_alloca, ast_bridge_topic_all(), ast_channel_entered_bridge_type(), ast_channel_lock, ast_channel_name(), ast_channel_uniqueid(), ast_channel_unlock, ast_copy_pj_str(), ast_debug, ast_framehook_attach(), ast_framehook_detach(), AST_FRAMEHOOK_INTERFACE_VERSION, ast_free, ast_log, ast_sip_push_task(), ast_str_buffer(), ast_str_create, ast_str_set(), ast_strdup, ast_strdupa, ast_strip(), ast_strlen_zero(), refer_blind::attended, refer_progress::bridge_sub, buf, refer_blind::context, transfer_channel_data::data, end, refer_progress::framehook, len(), LOG_ERROR, LOG_WARNING, NULL, pbx_builtin_getvar_helper(), pbx_builtin_setvar_helper(), prefix, refer_blind::progress, refer_blind::rdata, refer_progress::refer_blind_progress, refer_progress_bridge(), refer_progress_framehook(), refer_progress_framehook_destroy(), refer_progress_notification_alloc(), refer_progress_notify(), refer_blind::refer_to, refer_blind::replaces, S_OR, refer_progress::serializer, stasis_subscribe_pool, stasis_subscription_accept_message_type(), stasis_subscription_change_type(), STASIS_SUBSCRIPTION_FILTER_SELECTIVE, stasis_subscription_set_filter(), refer_progress::transfer_data, refer_progress::transferee, and ast_framehook_interface::version.

Referenced by refer_incoming_attended_request(), and refer_incoming_blind_request().

refer_client_on_evsub_state()

static void refer_client_on_evsub_state ( pjsip_evsub *  sub, pjsip_event *  event  )

static

Definition at line 1086 of file res_pjsip_refer.c.

{
    pjsip_tx_data *tdata;
    RAII_VAR(struct ast_sip_endpoint *, endpt, NULL, ao2_cleanup);
    struct refer_out_of_dialog *refer_data;
    int refer_success;
    int res = 0;
 
    if (!event) {
        return;
    }
 
    refer_data = pjsip_evsub_get_mod_data(sub, refer_out_of_dialog_module.id);
    if (!refer_data || !refer_data->dlg) {
        return;
    }
 
    endpt = ast_sip_dialog_get_endpoint(refer_data->dlg);
 
    if (pjsip_evsub_get_state(sub) == PJSIP_EVSUB_STATE_ACCEPTED) {
        /* Check if subscription is suppressed and terminate and send completion code, if so. */
        pjsip_rx_data *rdata;
        pjsip_generic_string_hdr *refer_sub;
        const pj_str_t REFER_SUB = { "Refer-Sub", 9 };
 
        ast_debug(3, "Refer accepted by %s\n", endpt ? ast_sorcery_object_get_id(endpt) : "(unknown endpoint)");
 
        /* Check if response message */
        if (event->type == PJSIP_EVENT_TSX_STATE && event->body.tsx_state.type == PJSIP_EVENT_RX_MSG) {
            rdata = event->body.tsx_state.src.rdata;
 
            /* Find Refer-Sub header */
            refer_sub = pjsip_msg_find_hdr_by_name(rdata->msg_info.msg, &REFER_SUB, NULL);
 
            /* Check if subscription is suppressed. If it is, the far end will not terminate it,
             * and the subscription will remain active until it times out.  Terminating it here
             * eliminates the unnecessary timeout.
             */
            if (refer_sub && !pj_stricmp2(&refer_sub->hvalue, "false")) {
                /* Since no subscription is desired, assume that call has been referred successfully
                 * and terminate subscription.
                 */
                pjsip_evsub_set_mod_data(sub, refer_out_of_dialog_module.id, NULL);
                pjsip_evsub_terminate(sub, PJ_TRUE);
                res = -1;
            }
        }
    } else if (pjsip_evsub_get_state(sub) == PJSIP_EVSUB_STATE_ACTIVE ||
            pjsip_evsub_get_state(sub) == PJSIP_EVSUB_STATE_TERMINATED) {
        /* Check for NOTIFY complete or error. */
        pjsip_msg *msg;
        pjsip_msg_body *body;
        pjsip_status_line status_line = { .code = 0 };
        pj_bool_t is_last;
        pj_status_t status;
 
        if (event->type == PJSIP_EVENT_TSX_STATE && event->body.tsx_state.type == PJSIP_EVENT_RX_MSG) {
            pjsip_rx_data *rdata;
            pj_str_t refer_str;
            pj_cstr(&refer_str, "REFER");
 
            rdata = event->body.tsx_state.src.rdata;
            msg = rdata->msg_info.msg;
 
            if (msg->type == PJSIP_RESPONSE_MSG
                && (event->body.tsx_state.tsx->status_code == 401
                    || event->body.tsx_state.tsx->status_code == 407)
                && pj_stristr(&refer_str, &event->body.tsx_state.tsx->method.name)
                && ++refer_data->authentication_challenge_count < MAX_RX_CHALLENGES
                && endpt) {
 
                if (!ast_sip_create_request_with_auth(&endpt->outbound_auths,
                    event->body.tsx_state.src.rdata, event->body.tsx_state.tsx->last_tx, &tdata)) {
                    /* Send authed REFER */
                    ast_sip_send_request(tdata, refer_data->dlg, NULL, NULL, NULL);
                    goto out;
                }
            }
 
            if (msg->type == PJSIP_REQUEST_MSG) {
                if (!pjsip_method_cmp(&msg->line.req.method, pjsip_get_notify_method())) {
                    body = msg->body;
                    if (body && !pj_stricmp2(&body->content_type.type, "message")
                        && !pj_stricmp2(&body->content_type.subtype, "sipfrag")) {
                        pjsip_parse_status_line((char *)body->data, body->len, &status_line);
                    }
                }
            } else {
                status_line.code = msg->line.status.code;
                status_line.reason = msg->line.status.reason;
            }
        } else {
            status_line.code = 500;
            status_line.reason = *pjsip_get_status_text(500);
        }
 
        is_last = (pjsip_evsub_get_state(sub) == PJSIP_EVSUB_STATE_TERMINATED);
        /* If the status code is >= 200, the subscription is finished. */
        if (status_line.code >= 200 || is_last) {
            res = -1;
 
            refer_success = status_line.code >= 200 && status_line.code < 300;
 
            /* If subscription not terminated and subscription is finished (status code >= 200)
             * terminate it */
            if (!is_last) {
                pjsip_tx_data *tdata;
 
                status = pjsip_evsub_initiate(sub, pjsip_get_subscribe_method(), 0, &tdata);
                if (status == PJ_SUCCESS) {
                    pjsip_evsub_send_request(sub, tdata);
                }
            }
            ast_debug(3, "Refer completed: %d %.*s (%s)\n",
                    status_line.code,
                    (int)status_line.reason.slen, status_line.reason.ptr,
                    refer_success ? "Success" : "Failure");
        }
    }
 
out:
    if (res) {
        ao2_cleanup(refer_data);
    }
}

References ao2_cleanup, ast_debug, ast_sip_create_request_with_auth(), ast_sip_dialog_get_endpoint(), ast_sip_send_request(), ast_sorcery_object_get_id(), MAX_RX_CHALLENGES, NULL, out, RAII_VAR, refer_out_of_dialog_module, status, and sub.

Referenced by refer_send().

refer_data_create()

static struct refer_data * refer_data_create ( const struct ast_refer *  refer )

static

Definition at line 868 of file res_pjsip_refer.c.

{
    char *uri_params;
    const char *destination;
    struct refer_data *rdata = ao2_alloc_options(sizeof(*rdata), refer_data_destroy, AO2_ALLOC_OPT_LOCK_NOLOCK);
 
    if (!rdata) {
        return NULL;
    }
 
    /* typecast to suppress const warning */
    rdata->refer = ast_refer_ref((struct ast_refer *) refer);
    destination = ast_refer_get_to(refer);
 
    /* To starts with 'pjsip:' which needs to be removed. */
    if (!(destination = strchr(destination, ':'))) {
        goto failure;
    }
    ++destination;/* Now skip the ':' */
 
    rdata->destination = ast_strdup(destination);
    if (!rdata->destination) {
        goto failure;
    }
 
    rdata->from = ast_strdup(ast_refer_get_from(refer));
    if (!rdata->from) {
        goto failure;
    }
 
    rdata->refer_to = ast_strdup(ast_refer_get_refer_to(refer));
    if (!rdata->refer_to) {
        goto failure;
    }
    rdata->to_self = ast_refer_get_to_self(refer);
 
    /*
     * Sometimes from URI can contain URI parameters, so remove them.
     *
     * sip:user;user-options@domain;uri-parameters
     */
    uri_params = strchr(rdata->from, '@');
    if (uri_params && (uri_params = strchr(uri_params, ';'))) {
        *uri_params = '\0';
    }
    return rdata;
 
failure:
    ao2_cleanup(rdata);
    return NULL;
}

References AO2_ALLOC_OPT_LOCK_NOLOCK, ao2_alloc_options, ao2_cleanup, ast_refer_get_from(), ast_refer_get_refer_to(), ast_refer_get_to(), ast_refer_get_to_self(), ast_refer_ref(), ast_strdup, refer_data::destination, refer_data::from, NULL, refer_data::refer, refer_data_destroy(), refer_data::refer_to, and refer_data::to_self.

Referenced by sip_refer_send().

refer_data_destroy()

static void refer_data_destroy ( void *  obj )

static

Definition at line 857 of file res_pjsip_refer.c.

{
    struct refer_data *rdata = obj;
 
    ast_free(rdata->destination);
    ast_free(rdata->from);
    ast_free(rdata->refer_to);
 
    ast_refer_destroy(rdata->refer);
}

References ast_free, ast_refer_destroy(), refer_data::destination, refer_data::from, refer_data::refer, and refer_data::refer_to.

Referenced by refer_data_create().

refer_incoming_attended_request()

static int refer_incoming_attended_request ( struct ast_sip_session *  session, pjsip_rx_data *  rdata, pjsip_sip_uri *  target_uri, pjsip_param *  replaces_param, struct refer_progress *  progress  )

static

Definition at line 1342 of file res_pjsip_refer.c.

{
    const pj_str_t str_replaces = { "Replaces", 8 };
    pj_str_t replaces_content;
    pjsip_replaces_hdr *replaces;
    int parsed_len;
    pjsip_dialog *dlg;
 
    pj_strdup_with_null(rdata->tp_info.pool, &replaces_content, &replaces_param->value);
 
    /* Parsing the parameter as a Replaces header easily grabs the needed information */
    if (!(replaces = pjsip_parse_hdr(rdata->tp_info.pool, &str_replaces, replaces_content.ptr,
        pj_strlen(&replaces_content), &parsed_len))) {
        ast_log(LOG_ERROR, "Received REFER request on channel '%s' from endpoint '%s' with invalid Replaces header, rejecting\n",
            ast_channel_name(session->channel), ast_sorcery_object_get_id(session->endpoint));
        return 400;
    }
 
    /* See if the dialog is local, or remote */
    if ((dlg = pjsip_ua_find_dialog(&replaces->call_id, &replaces->to_tag, &replaces->from_tag, PJ_TRUE))) {
        RAII_VAR(struct ast_sip_session *, other_session, ast_sip_dialog_get_session(dlg), ao2_cleanup);
        struct refer_attended *attended;
 
        pjsip_dlg_dec_lock(dlg);
 
        if (!other_session) {
            ast_debug(3, "Received REFER request on channel '%s' from endpoint '%s' for local dialog but no session exists on it\n",
                ast_channel_name(session->channel), ast_sorcery_object_get_id(session->endpoint));
            return 603;
        }
 
        /* We defer actually doing the attended transfer to the other session so no deadlock can occur */
        if (!(attended = refer_attended_alloc(session, other_session, progress))) {
            ast_log(LOG_ERROR, "Received REFER request on channel '%s' from endpoint '%s' for local dialog but could not allocate structure to complete, rejecting\n",
                ast_channel_name(session->channel), ast_sorcery_object_get_id(session->endpoint));
            return 500;
        }
 
        if (ast_sip_session_defer_termination(session)) {
            ast_log(LOG_ERROR, "Received REFER request on channel '%s' from endpoint '%s' for local dialog but could not defer termination, rejecting\n",
                ast_channel_name(session->channel), ast_sorcery_object_get_id(session->endpoint));
            ao2_cleanup(attended);
            return 500;
        }
 
        /* Push it to the other session, which will have both channels with minimal locking */
        if (ast_sip_push_task(other_session->serializer, refer_attended_task, attended)) {
            ast_sip_session_end_if_deferred(session);
            ast_sip_session_defer_termination_cancel(session);
            ao2_cleanup(attended);
            return 500;
        }
 
        ast_debug(3, "Attended transfer from '%s' pushed to second channel serializer\n",
            ast_channel_name(session->channel));
 
        return 200;
    } else {
        const char *context;
        struct refer_blind refer = { 0, };
        int response;
 
        DETERMINE_TRANSFER_CONTEXT(context, session);
 
        if (!ast_exists_extension(NULL, context, "external_replaces", 1, NULL)) {
            ast_log(LOG_ERROR, "Received REFER for remote session on channel '%s' from endpoint '%s' but 'external_replaces' extension not found in context %s\n",
                ast_channel_name(session->channel), ast_sorcery_object_get_id(session->endpoint), context);
            return 404;
        }
 
        refer.context = context;
        refer.progress = progress;
        refer.rdata = rdata;
        refer.replaces = replaces;
        refer.refer_to = target_uri;
        refer.attended = 1;
 
        if (ast_sip_session_defer_termination(session)) {
            ast_log(LOG_ERROR, "Received REFER for remote session on channel '%s' from endpoint '%s' but could not defer termination, rejecting\n",
                ast_channel_name(session->channel),
                ast_sorcery_object_get_id(session->endpoint));
            return 500;
        }
 
        response = xfer_response_code2sip(ast_bridge_transfer_blind(1, session->channel,
            "external_replaces", context, refer_blind_callback, &refer));
 
        ast_sip_session_end_if_deferred(session);
        if (response != 200) {
            ast_sip_session_defer_termination_cancel(session);
        }
 
        return response;
    }
}

References ao2_cleanup, ast_bridge_transfer_blind(), ast_channel_name(), ast_debug, ast_exists_extension(), ast_log, ast_sip_dialog_get_session(), ast_sip_push_task(), ast_sip_session_defer_termination(), ast_sip_session_defer_termination_cancel(), ast_sip_session_end_if_deferred(), ast_sorcery_object_get_id(), refer_blind::attended, voicemailpwcheck::context, refer_blind::context, DETERMINE_TRANSFER_CONTEXT, LOG_ERROR, NULL, refer_blind::progress, RAII_VAR, refer_blind::rdata, refer_attended_alloc(), refer_attended_task(), refer_blind_callback(), refer_blind::refer_to, refer_blind::replaces, session, and xfer_response_code2sip().

Referenced by refer_incoming_refer_request().

refer_incoming_blind_request()

static int refer_incoming_blind_request ( struct ast_sip_session *  session, pjsip_rx_data *  rdata, pjsip_sip_uri *  target, struct refer_progress *  progress  )

static

Definition at line 1439 of file res_pjsip_refer.c.

{
    const char *context;
    char exten[AST_MAX_EXTENSION];
    struct refer_blind refer = { 0, };
    int response;
 
    /* If no explicit transfer context has been provided use their configured context */
    DETERMINE_TRANSFER_CONTEXT(context, session);
 
    /* Using the user portion of the target URI see if it exists as a valid extension in their context */
    ast_copy_pj_str(exten, &target->user, sizeof(exten));
 
    /*
     * We may want to match in the dialplan without any user
     * options getting in the way.
     */
    AST_SIP_USER_OPTIONS_TRUNCATE_CHECK(exten);
 
    /* Uri without exten */
    if (ast_strlen_zero(exten)) {
        ast_copy_string(exten, "s", sizeof(exten));
        ast_debug(3, "Channel '%s' from endpoint '%s' attempted blind transfer to a target without extension. Target was set to 's@%s'\n",
            ast_channel_name(session->channel), ast_sorcery_object_get_id(session->endpoint), context);
    }
 
    if (!ast_exists_extension(NULL, context, exten, 1, NULL)) {
        ast_log(LOG_ERROR, "Channel '%s' from endpoint '%s' attempted blind transfer to '%s@%s' but target does not exist\n",
            ast_channel_name(session->channel), ast_sorcery_object_get_id(session->endpoint), exten, context);
        return 404;
    }
 
    refer.context = context;
    refer.progress = progress;
    refer.rdata = rdata;
    refer.refer_to = target;
    refer.attended = 0;
 
    if (ast_sip_session_defer_termination(session)) {
        ast_log(LOG_ERROR, "Channel '%s' from endpoint '%s' attempted blind transfer but could not defer termination, rejecting\n",
            ast_channel_name(session->channel),
            ast_sorcery_object_get_id(session->endpoint));
        return 500;
    }
 
    response = xfer_response_code2sip(ast_bridge_transfer_blind(1, session->channel,
        exten, context, refer_blind_callback, &refer));
 
    ast_sip_session_end_if_deferred(session);
    if (response != 200) {
        ast_sip_session_defer_termination_cancel(session);
    }
 
    return response;
}

References ast_bridge_transfer_blind(), ast_channel_name(), ast_copy_pj_str(), ast_copy_string(), ast_debug, ast_exists_extension(), ast_log, AST_MAX_EXTENSION, ast_sip_session_defer_termination(), ast_sip_session_defer_termination_cancel(), ast_sip_session_end_if_deferred(), AST_SIP_USER_OPTIONS_TRUNCATE_CHECK, ast_sorcery_object_get_id(), ast_strlen_zero(), refer_blind::attended, voicemailpwcheck::context, refer_blind::context, DETERMINE_TRANSFER_CONTEXT, LOG_ERROR, NULL, refer_blind::progress, refer_blind::rdata, refer_blind_callback(), refer_blind::refer_to, session, and xfer_response_code2sip().

Referenced by refer_incoming_refer_request().

refer_incoming_invite_request()

static int refer_incoming_invite_request ( struct ast_sip_session *  session, struct pjsip_rx_data *  rdata  )

static

Definition at line 1522 of file res_pjsip_refer.c.

{
    pjsip_dialog *other_dlg = NULL;
    pjsip_tx_data *packet;
    int response = 0;
    RAII_VAR(struct ast_sip_session *, other_session, NULL, ao2_cleanup);
    struct invite_replaces invite;
 
    /* If a Replaces header is present make sure it is valid */
    if (pjsip_replaces_verify_request(rdata, &other_dlg, PJ_TRUE, &packet) != PJ_SUCCESS) {
        response = packet->msg->line.status.code;
        ast_assert(response != 0);
        pjsip_tx_data_dec_ref(packet);
        goto inv_replace_failed;
    }
 
    /* If no other dialog exists then this INVITE request does not have a Replaces header */
    if (!other_dlg) {
        return 0;
    }
 
    other_session = ast_sip_dialog_get_session(other_dlg);
    pjsip_dlg_dec_lock(other_dlg);
 
    /* Don't accept an in-dialog INVITE with Replaces as it does not make much sense */
    if (session->inv_session->dlg->state == PJSIP_DIALOG_STATE_ESTABLISHED) {
        response = 488;
        goto inv_replace_failed;
    }
 
    if (!other_session) {
        ast_debug(3, "INVITE with Replaces received on channel '%s' from endpoint '%s', but requested session does not exist\n",
            ast_channel_name(session->channel), ast_sorcery_object_get_id(session->endpoint));
        response = 481;
        goto inv_replace_failed;
    }
 
    invite.session = other_session;
 
    if (ast_sip_push_task_wait_serializer(other_session->serializer, invite_replaces,
        &invite)) {
        response = 481;
        goto inv_replace_failed;
    }
 
    ast_channel_lock(session->channel);
    ast_setstate(session->channel, AST_STATE_RING);
    ast_channel_unlock(session->channel);
    ast_raw_answer(session->channel);
 
    ast_debug(3, "INVITE with Replaces being attempted.  '%s' --> '%s'\n",
        ast_channel_name(session->channel), ast_channel_name(invite.channel));
 
    /* Unhold the channel now, as later we are not having access to it anymore */
    ast_queue_unhold(session->channel);
    ast_queue_frame(session->channel, &ast_null_frame);
 
    if (!invite.bridge) {
        struct ast_channel *chan = session->channel;
 
        /*
         * This will use a synchronous task but we aren't operating in
         * the serializer at this point in time, so it won't deadlock.
         */
        if (!ast_channel_move(invite.channel, chan)) {
            /*
             * We can't directly use session->channel because ast_channel_move()
             * does a masquerade which changes session->channel to a different
             * channel.  To ensure we work on the right channel we store a
             * pointer locally before we begin so it remains valid.
             */
            ast_hangup(chan);
        } else {
            response = AST_CAUSE_FAILURE;
        }
    } else {
        if (ast_bridge_impart(invite.bridge, session->channel, invite.channel, NULL,
            AST_BRIDGE_IMPART_CHAN_INDEPENDENT)) {
            response = AST_CAUSE_FAILURE;
        }
    }
 
    ast_channel_unref(invite.channel);
    ao2_cleanup(invite.bridge);
 
    if (!response) {
        /*
         * On success we cannot use session->channel in the debug message.
         * This thread either no longer has a ref to session->channel or
         * session->channel is no longer the original channel.
         */
        ast_debug(3, "INVITE with Replaces successfully completed.\n");
    } else {
        ast_debug(3, "INVITE with Replaces failed on channel '%s', hanging up with cause '%d'\n",
            ast_channel_name(session->channel), response);
        ast_channel_lock(session->channel);
        ast_channel_hangupcause_set(session->channel, response);
        ast_channel_unlock(session->channel);
        ast_hangup(session->channel);
    }
 
    return 1;
 
inv_replace_failed:
    if (session->inv_session->dlg->state != PJSIP_DIALOG_STATE_ESTABLISHED) {
        ast_debug(3, "INVITE with Replaces failed on channel '%s', sending response of '%d'\n",
            ast_channel_name(session->channel), response);
        session->defer_terminate = 1;
        ast_hangup(session->channel);
 
        if (pjsip_inv_end_session(session->inv_session, response, NULL, &packet) == PJ_SUCCESS
            && packet) {
            ast_sip_session_send_response(session, packet);
        }
    } else {
        ast_debug(3, "INVITE with Replaces in-dialog on channel '%s', hanging up\n",
            ast_channel_name(session->channel));
        ast_queue_hangup(session->channel);
    }
 
    return 1;
}

References ao2_cleanup, ast_assert, ast_bridge_impart(), AST_BRIDGE_IMPART_CHAN_INDEPENDENT, AST_CAUSE_FAILURE, ast_channel_hangupcause_set(), ast_channel_lock, ast_channel_move(), ast_channel_name(), ast_channel_unlock, ast_channel_unref, ast_debug, ast_hangup(), ast_null_frame, ast_queue_frame(), ast_queue_hangup(), ast_queue_unhold(), ast_raw_answer(), ast_setstate(), ast_sip_dialog_get_session(), ast_sip_push_task_wait_serializer(), ast_sip_session_send_response(), ast_sorcery_object_get_id(), AST_STATE_RING, invite_replaces::bridge, invite_replaces::channel, NULL, RAII_VAR, invite_replaces::session, and session.

Referenced by refer_incoming_request().

refer_incoming_refer_request()

static int refer_incoming_refer_request ( struct ast_sip_session *  session, struct pjsip_rx_data *  rdata  )

static

Definition at line 1645 of file res_pjsip_refer.c.

{
    pjsip_generic_string_hdr *refer_to;
    char *uri;
    size_t uri_size;
    pjsip_uri *target;
    pjsip_sip_uri *target_uri;
    RAII_VAR(struct refer_progress *, progress, NULL, ao2_cleanup);
    pjsip_param *replaces;
    int response;
 
    static const pj_str_t str_refer_to = { "Refer-To", 8 };
    static const pj_str_t str_refer_to_s = { "r", 1 };
    static const pj_str_t str_replaces = { "Replaces", 8 };
 
    if (!session->channel) {
        /* No channel to refer.  Likely because the call was just hung up. */
        pjsip_dlg_respond(session->inv_session->dlg, rdata, 404, NULL, NULL, NULL);
        ast_debug(3, "Received a REFER on a session with no channel from endpoint '%s'.\n",
            ast_sorcery_object_get_id(session->endpoint));
        return 0;
    }
 
    if (!session->endpoint->allowtransfer) {
        pjsip_dlg_respond(session->inv_session->dlg, rdata, 603, NULL, NULL, NULL);
        ast_log(LOG_WARNING, "Endpoint %s transfer attempt blocked due to configuration\n",
                ast_sorcery_object_get_id(session->endpoint));
        return 0;
    }
 
    /* A Refer-To header is required */
    refer_to = pjsip_msg_find_hdr_by_names(rdata->msg_info.msg, &str_refer_to, &str_refer_to_s, NULL);
    if (!refer_to) {
        pjsip_dlg_respond(session->inv_session->dlg, rdata, 400, NULL, NULL, NULL);
        ast_debug(3, "Received a REFER without Refer-To on channel '%s' from endpoint '%s'\n",
            ast_channel_name(session->channel), ast_sorcery_object_get_id(session->endpoint));
        return 0;
    }
 
    /* The ast_copy_pj_str to uri is needed because it puts the NULL terminator to the uri
     * as pjsip_parse_uri require a NULL terminated uri
     */
 
    uri_size = pj_strlen(&refer_to->hvalue) + 1;
    uri = ast_alloca(uri_size);
    ast_copy_pj_str(uri, &refer_to->hvalue, uri_size);
 
    target = pjsip_parse_uri(rdata->tp_info.pool, uri, uri_size - 1, 0);
 
    if (!target
        || (!PJSIP_URI_SCHEME_IS_SIP(target)
            && !PJSIP_URI_SCHEME_IS_SIPS(target))) {
 
        pjsip_dlg_respond(session->inv_session->dlg, rdata, 400, NULL, NULL, NULL);
        ast_debug(3, "Received a REFER without a parseable Refer-To ('%s') on channel '%s' from endpoint '%s'\n",
            uri, ast_channel_name(session->channel), ast_sorcery_object_get_id(session->endpoint));
        return 0;
    }
    target_uri = pjsip_uri_get_uri(target);
 
    /* Set up REFER progress subscription if requested/possible */
    if (refer_progress_alloc(session, rdata, &progress)) {
        pjsip_dlg_respond(session->inv_session->dlg, rdata, 500, NULL, NULL, NULL);
        ast_debug(3, "Could not set up subscription for REFER on channel '%s' from endpoint '%s'\n",
            ast_channel_name(session->channel), ast_sorcery_object_get_id(session->endpoint));
        return 0;
    }
 
    /* Determine if this is an attended or blind transfer */
    if ((replaces = pjsip_param_find(&target_uri->header_param, &str_replaces)) ||
        (replaces = pjsip_param_find(&target_uri->other_param, &str_replaces))) {
        response = refer_incoming_attended_request(session, rdata, target_uri, replaces, progress);
    } else {
        response = refer_incoming_blind_request(session, rdata, target_uri, progress);
    }
 
    if (!progress) {
        /* The transferer has requested no subscription, so send a final response immediately */
        pjsip_tx_data *tdata;
        const pj_str_t str_refer_sub = { "Refer-Sub", 9 };
        const pj_str_t str_false = { "false", 5 };
        pjsip_hdr *hdr;
 
        ast_debug(3, "Progress monitoring not requested for REFER on channel '%s' from endpoint '%s', sending immediate response of '%d'\n",
            ast_channel_name(session->channel), ast_sorcery_object_get_id(session->endpoint), response);
 
        if (pjsip_dlg_create_response(session->inv_session->dlg, rdata, response, NULL, &tdata) != PJ_SUCCESS) {
            pjsip_dlg_respond(session->inv_session->dlg, rdata, response, NULL, NULL, NULL);
            return 0;
        }
 
        hdr = (pjsip_hdr*)pjsip_generic_string_hdr_create(tdata->pool, &str_refer_sub, &str_false);
        pjsip_msg_add_hdr(tdata->msg, hdr);
 
        pjsip_dlg_send_response(session->inv_session->dlg, pjsip_rdata_get_tsx(rdata), tdata);
    } else if (response != 200) {
        /* Since this failed we can send a final NOTIFY now and terminate the subscription */
        struct refer_progress_notification *notification = refer_progress_notification_alloc(progress, response, PJSIP_EVSUB_STATE_TERMINATED);
 
        if (notification) {
            /* The refer_progress_notify function will call ao2_cleanup on this for us */
            if (ast_sip_push_task(progress->serializer, refer_progress_notify, notification)) {
                ao2_cleanup(notification);
            }
        }
    }
 
    return 0;
}

References ao2_cleanup, ast_alloca, ast_channel_name(), ast_copy_pj_str(), ast_debug, ast_log, ast_sip_push_task(), ast_sorcery_object_get_id(), LOG_WARNING, NULL, RAII_VAR, refer_incoming_attended_request(), refer_incoming_blind_request(), refer_progress_alloc(), refer_progress_notification_alloc(), refer_progress_notify(), refer_progress_notification::response, and session.

Referenced by refer_incoming_request().

refer_incoming_request()

static int refer_incoming_request ( struct ast_sip_session *  session, pjsip_rx_data *  rdata  )

static

Definition at line 1755 of file res_pjsip_refer.c.

{
    if (!pjsip_method_cmp(&rdata->msg_info.msg->line.req.method, pjsip_get_refer_method())) {
        return refer_incoming_refer_request(session, rdata);
    } else if (!pjsip_method_cmp(&rdata->msg_info.msg->line.req.method, &pjsip_invite_method)) {
        return refer_incoming_invite_request(session, rdata);
    } else {
        return 0;
    }
}

References refer_incoming_invite_request(), refer_incoming_refer_request(), and session.

refer_on_tx_request()

static pj_status_t refer_on_tx_request ( pjsip_tx_data *  tdata )

static

Definition at line 1015 of file res_pjsip_refer.c.

                                                             {
    RAII_VAR(struct ast_str *, refer_to_str, ast_str_create(PJSIP_MAX_URL_SIZE), ast_free_ptr);
    const pj_str_t REFER_TO = { "Refer-To", 8 };
    pjsip_generic_string_hdr *refer_to_hdr;
    pjsip_dialog *dlg;
    struct refer_data *refer_data;
    pjsip_uri *parsed_uri;
    pjsip_sip_uri *refer_to_uri;
 
    /*
     * If this is a request in response to a 401/407 Unauthorized challenge, the
     * Refer-To URI has been rewritten already, so don't attempt to re-write it again.
     * Checking for presence of the Authorization header is not an ideal solution. We do this because
     * there exists some race condition where this dialog is not the same as the one used
     * to send the original request in which case we don't have the correct refer_data.
     */
    if (!refer_to_str
        || pjsip_msg_find_hdr(tdata->msg, PJSIP_H_AUTHORIZATION, NULL)
        || !(dlg = pjsip_tdata_get_dlg(tdata))
        || !(refer_data = pjsip_dlg_get_mod_data(dlg, refer_out_of_dialog_module.id))
        || !refer_data->to_self
        || !(parsed_uri = get_refer_to_uri(tdata))) {
        goto out;
    }
    refer_to_uri = pjsip_uri_get_uri(parsed_uri);
    ast_sip_rewrite_uri_to_local(refer_to_uri, tdata);
 
    pjsip_uri_print(PJSIP_URI_IN_CONTACT_HDR, parsed_uri, ast_str_buffer(refer_to_str), ast_str_size(refer_to_str));
    refer_to_hdr = pjsip_msg_find_hdr_by_name(tdata->msg, &REFER_TO, NULL);
    pj_strdup2(tdata->pool, &refer_to_hdr->hvalue, ast_str_buffer(refer_to_str));
 
out:
    return PJ_SUCCESS;
}

References ast_free_ptr(), ast_sip_rewrite_uri_to_local(), ast_str_buffer(), ast_str_create, ast_str_size(), get_refer_to_uri(), NULL, out, RAII_VAR, refer_out_of_dialog_module, and refer_data::to_self.

refer_out_of_dialog_destroy()

static void refer_out_of_dialog_destroy ( void *  obj )

static

Destructor for REFER out of dialog structure.

Definition at line 1067 of file res_pjsip_refer.c.

                                                   {
    struct refer_out_of_dialog *data = obj;
 
    if (data->dlg) {
        /* ast_sip_push_task_wait_servant should not be called in a destructor,
         * however in this case it seems to be fine.
         */
        ast_sip_push_task_wait_servant(refer_serializer, refer_unreference_dialog, data);
    }
}

References ast_sip_push_task_wait_servant(), refer_out_of_dialog::dlg, refer_serializer, and refer_unreference_dialog().

Referenced by refer_send().

refer_outgoing_request()

static void refer_outgoing_request ( struct ast_sip_session *  session, struct pjsip_tx_data *  tdata  )

static

Definition at line 1799 of file res_pjsip_refer.c.

{
    if (pjsip_method_cmp(&tdata->msg->line.req.method, &pjsip_invite_method)
        || !session->channel
        || session->inv_session->state != PJSIP_INV_STATE_NULL) {
        return;
    }
 
    ast_channel_lock(session->channel);
    add_header_from_channel_var(session->channel, "SIPREPLACESHDR", "Replaces", tdata);
    add_header_from_channel_var(session->channel, "SIPREFERREDBYHDR", "Referred-By", tdata);
    ast_channel_unlock(session->channel);
}

References add_header_from_channel_var(), ast_channel_lock, ast_channel_unlock, and session.

refer_progress_alloc()

static int refer_progress_alloc ( struct ast_sip_session *  session, pjsip_rx_data *  rdata, struct refer_progress **  progress  )

static

Internal helper function which sets up a refer progress structure if needed.

Definition at line 387 of file res_pjsip_refer.c.

{
    const pj_str_t str_refer_sub = { "Refer-Sub", 9 };
    pjsip_generic_string_hdr *refer_sub = NULL;
    const pj_str_t str_true = { "true", 4 };
    pjsip_hdr hdr_list;
    char tps_name[AST_TASKPROCESSOR_MAX_NAME + 1];
 
    *progress = NULL;
 
    /* Grab the optional Refer-Sub header, it can be used to suppress the implicit subscription */
    refer_sub = pjsip_msg_find_hdr_by_name(rdata->msg_info.msg, &str_refer_sub, NULL);
    if ((refer_sub && pj_strnicmp(&refer_sub->hvalue, &str_true, 4))) {
        return 0;
    }
 
    if (!(*progress = ao2_alloc(sizeof(struct refer_progress), refer_progress_destroy))) {
        return -1;
    }
 
    ast_debug(3, "Created progress monitor '%p' for transfer occurring from channel '%s' and endpoint '%s'\n",
        progress, ast_channel_name(session->channel), ast_sorcery_object_get_id(session->endpoint));
 
    (*progress)->refer_blind_progress = session->endpoint->refer_blind_progress;
 
    (*progress)->framehook = -1;
 
    /* Create name with seq number appended. */
    ast_taskprocessor_build_name(tps_name, sizeof(tps_name), "pjsip/refer/%s",
        ast_sorcery_object_get_id(session->endpoint));
 
    if (!((*progress)->serializer = ast_sip_create_serializer(tps_name))) {
        goto error;
    }
 
    /* Create the implicit subscription for monitoring of this transfer */
    if (pjsip_xfer_create_uas(session->inv_session->dlg, &refer_progress_evsub_cb, rdata, &(*progress)->sub) != PJ_SUCCESS) {
        goto error;
    }
 
    /* To prevent a potential deadlock we need the dialog so we can lock/unlock */
    (*progress)->dlg = session->inv_session->dlg;
    /* We also need to make sure it stays around until we're done with it */
    pjsip_dlg_inc_session((*progress)->dlg, &refer_progress_module);
 
 
    /* Associate the REFER progress structure with the subscription */
    ao2_ref(*progress, +1);
    pjsip_evsub_set_mod_data((*progress)->sub, refer_progress_module.id, *progress);
 
    pj_list_init(&hdr_list);
    if (refer_sub) {
        pjsip_hdr *hdr = (pjsip_hdr*)pjsip_generic_string_hdr_create(session->inv_session->dlg->pool, &str_refer_sub, &str_true);
 
        pj_list_push_back(&hdr_list, hdr);
    }
 
    /* Accept the REFER request */
    ast_debug(3, "Accepting REFER request for progress monitor '%p'\n", *progress);
    pjsip_xfer_accept((*progress)->sub, rdata, 202, &hdr_list);
 
    return 0;
 
error:
    ao2_cleanup(*progress);
    *progress = NULL;
    return -1;
}

References ao2_alloc, ao2_cleanup, ao2_ref, ast_channel_name(), ast_debug, ast_sip_create_serializer(), ast_sorcery_object_get_id(), ast_taskprocessor_build_name(), AST_TASKPROCESSOR_MAX_NAME, error(), NULL, refer_progress::rdata, refer_progress_destroy(), refer_progress_evsub_cb, refer_progress_module, and session.

Referenced by refer_incoming_refer_request().

refer_progress_bridge()

static void refer_progress_bridge ( void *  data, struct stasis_subscription *  sub, struct stasis_message *  message  )

static

Definition at line 186 of file res_pjsip_refer.c.

{
    struct refer_progress *progress = data;
    struct ast_bridge_blob *enter_blob;
    struct refer_progress_notification *notification;
    struct ast_channel *chan;
 
    if (stasis_subscription_final_message(sub, message)) {
        ao2_ref(progress, -1);
        return;
    }
 
    if (ast_channel_entered_bridge_type() != stasis_message_type(message)) {
        /* Don't care */
        return;
    }
 
    enter_blob = stasis_message_data(message);
    if (strcmp(enter_blob->channel->base->uniqueid, progress->transferee)) {
        /* Don't care */
        return;
    }
 
    if (!progress->transfer_data->completed) {
        /* We can't act on this message because the transfer_channel_data doesn't show that
         * the transfer is ready to progress */
        return;
    }
 
    /* OMG the transferee is joining a bridge. His call got answered! */
    notification = refer_progress_notification_alloc(progress, 200, PJSIP_EVSUB_STATE_TERMINATED);
    if (notification) {
        if (ast_sip_push_task(progress->serializer, refer_progress_notify, notification)) {
            ao2_cleanup(notification);
        }
        progress->bridge_sub = stasis_unsubscribe(progress->bridge_sub);
    }
 
    chan = ast_channel_get_by_name(progress->transferee);
    if (!chan) {
        /* The channel is already gone */
        return;
    }
 
    ast_channel_lock(chan);
    ast_debug(3, "Detaching REFER progress monitoring hook from '%s' as it has joined a bridge\n",
        ast_channel_name(chan));
    ast_framehook_detach(chan, progress->framehook);
    ast_channel_unlock(chan);
 
    ast_channel_unref(chan);
}

References ao2_cleanup, ao2_ref, ast_channel_entered_bridge_type(), ast_channel_get_by_name(), ast_channel_lock, ast_channel_name(), ast_channel_unlock, ast_channel_unref, ast_debug, ast_framehook_detach(), ast_sip_push_task(), ast_channel_snapshot::base, ast_bridge_blob::channel, refer_progress_notification_alloc(), refer_progress_notify(), stasis_message_data(), stasis_message_type(), stasis_subscription_final_message(), stasis_unsubscribe(), sub, and ast_channel_snapshot_base::uniqueid.

Referenced by refer_blind_callback().

refer_progress_destroy()

static void refer_progress_destroy ( void *  obj )

static

Destructor for REFER progress sutrcture.

Definition at line 354 of file res_pjsip_refer.c.

{
    struct refer_progress *progress = obj;
 
    if (progress->bridge_sub) {
        progress->bridge_sub = stasis_unsubscribe(progress->bridge_sub);
    }
 
    if (progress->dlg) {
        /*
         * Although the dlg session count was incremented in a pjsip servant
         * thread, there's no guarantee that the last thread to unref this progress
         * object was one.  Before we decrement, we need to make sure that this
         * is either a servant thread or that we push the decrement to a
         * serializer that is one.
         *
         * Because pjsip_dlg_dec_session requires the dialog lock, we don't want
         * to wait on the task to complete if we had to push it to a serializer.
         */
        if (ast_sip_thread_is_servant()) {
            pjsip_dlg_dec_session(progress->dlg, &refer_progress_module);
        } else {
            ast_sip_push_task(NULL, dlg_releaser_task, progress->dlg);
        }
    }
 
    ao2_cleanup(progress->transfer_data);
 
    ast_free(progress->transferee);
    ast_taskprocessor_unreference(progress->serializer);
}

References ao2_cleanup, ast_free, ast_sip_push_task(), ast_sip_thread_is_servant(), ast_taskprocessor_unreference(), dlg_releaser_task(), NULL, refer_progress_module, and stasis_unsubscribe().

Referenced by refer_progress_alloc().

refer_progress_framehook()

static struct ast_frame * refer_progress_framehook ( struct ast_channel *  chan, struct ast_frame *  f, enum ast_framehook_event  event, void *  data  )

static

Progress monitoring frame hook - examines frames to determine state of transfer.

Definition at line 241 of file res_pjsip_refer.c.

{
    struct refer_progress *progress = data;
    struct refer_progress_notification *notification = NULL;
 
    /* We only care about frames *to* the channel */
    if (!f || (event != AST_FRAMEHOOK_EVENT_WRITE)) {
        return f;
    }
 
    /* If the completed flag hasn't been raised, skip this pass. */
    if (!progress->transfer_data->completed) {
        return f;
    }
 
    /* Determine the state of the REFER based on the control frames (or voice frames) passing */
    if (f->frametype == AST_FRAME_VOICE && !progress->subclass) {
        /* Media is passing without progress, this means the call has been answered */
        progress->subclass = AST_CONTROL_ANSWER;
        notification = refer_progress_notification_alloc(progress, 200, PJSIP_EVSUB_STATE_TERMINATED);
    } else if (f->frametype == AST_FRAME_CONTROL) {
        /* Based on the control frame being written we can send a NOTIFY advising of the progress */
        if ((f->subclass.integer == AST_CONTROL_RING) || (f->subclass.integer == AST_CONTROL_RINGING)) {
            /* Don't set progress->subclass; an ANSWER can still follow */
            notification = refer_progress_notification_alloc(progress, 180, PJSIP_EVSUB_STATE_ACTIVE);
        } else if (f->subclass.integer == AST_CONTROL_BUSY) {
            progress->subclass = f->subclass.integer;
            notification = refer_progress_notification_alloc(progress, 486, PJSIP_EVSUB_STATE_TERMINATED);
        } else if (f->subclass.integer == AST_CONTROL_CONGESTION) {
            progress->subclass = f->subclass.integer;
            notification = refer_progress_notification_alloc(progress, 503, PJSIP_EVSUB_STATE_TERMINATED);
        } else if (f->subclass.integer == AST_CONTROL_PROGRESS) {
            /* Don't set progress->subclass; an ANSWER can still follow */
            notification = refer_progress_notification_alloc(progress, 183, PJSIP_EVSUB_STATE_ACTIVE);
        } else if (f->subclass.integer == AST_CONTROL_PROCEEDING) {
            /* Don't set progress->subclass; an ANSWER can still follow */
            notification = refer_progress_notification_alloc(progress, 100, PJSIP_EVSUB_STATE_ACTIVE);
        } else if (f->subclass.integer == AST_CONTROL_ANSWER) {
            progress->subclass = f->subclass.integer;
            notification = refer_progress_notification_alloc(progress, 200, PJSIP_EVSUB_STATE_TERMINATED);
        }
    }
 
    /* If a notification is due to be sent push it to the thread pool */
    if (notification) {
        /* If the subscription is being terminated we don't need the frame hook any longer */
        if (notification->state == PJSIP_EVSUB_STATE_TERMINATED) {
            ast_debug(3, "Detaching REFER progress monitoring hook from '%s' as subscription is being terminated\n",
                ast_channel_name(chan));
            ast_framehook_detach(chan, progress->framehook);
        }
 
        if (ast_sip_push_task(progress->serializer, refer_progress_notify, notification)) {
            ao2_cleanup(notification);
        }
    }
 
    return f;
}

References ao2_cleanup, ast_channel_name(), AST_CONTROL_ANSWER, AST_CONTROL_BUSY, AST_CONTROL_CONGESTION, AST_CONTROL_PROCEEDING, AST_CONTROL_PROGRESS, AST_CONTROL_RING, AST_CONTROL_RINGING, ast_debug, AST_FRAME_CONTROL, AST_FRAME_VOICE, ast_framehook_detach(), AST_FRAMEHOOK_EVENT_WRITE, ast_sip_push_task(), ast_frame::frametype, ast_frame_subclass::integer, NULL, refer_progress_notification_alloc(), refer_progress_notify(), refer_progress_notification::state, and ast_frame::subclass.

Referenced by refer_blind_callback().

refer_progress_framehook_destroy()

static void refer_progress_framehook_destroy ( void *  data )

static

Destroy callback for monitoring framehook.

Definition at line 302 of file res_pjsip_refer.c.

{
    struct refer_progress *progress = data;
    struct refer_progress_notification *notification = refer_progress_notification_alloc(progress, 503, PJSIP_EVSUB_STATE_TERMINATED);
 
    if (notification && ast_sip_push_task(progress->serializer, refer_progress_notify, notification)) {
        ao2_cleanup(notification);
    }
 
    if (progress->bridge_sub) {
        progress->bridge_sub = stasis_unsubscribe(progress->bridge_sub);
    }
 
    ao2_cleanup(progress);
}

References ao2_cleanup, ast_sip_push_task(), refer_progress_notification_alloc(), refer_progress_notify(), and stasis_unsubscribe().

Referenced by refer_blind_callback().

refer_progress_notification_alloc()

static struct refer_progress_notification * refer_progress_notification_alloc ( struct refer_progress *  progress, int  response, pjsip_evsub_state  state  )

static

Allocator for REFER Progress notification structure.

Definition at line 99 of file res_pjsip_refer.c.

{
    struct refer_progress_notification *notification = ao2_alloc(sizeof(*notification), refer_progress_notification_destroy);
 
    if (!notification) {
        return NULL;
    }
 
    ao2_ref(progress, +1);
    notification->progress = progress;
    notification->response = response;
    notification->state = state;
 
    return notification;
}

References ao2_alloc, ao2_ref, NULL, refer_progress_notification::progress, refer_progress_notification_destroy(), refer_progress_notification::response, state, and refer_progress_notification::state.

Referenced by refer_attended_task(), refer_blind_callback(), refer_incoming_refer_request(), refer_progress_bridge(), refer_progress_framehook(), and refer_progress_framehook_destroy().

refer_progress_notification_destroy()

static void refer_progress_notification_destroy ( void *  obj )

static

Destructor for REFER Progress notification structure.

Definition at line 91 of file res_pjsip_refer.c.

{
    struct refer_progress_notification *notification = obj;
 
    ao2_cleanup(notification->progress);
}

References ao2_cleanup, and refer_progress_notification::progress.

Referenced by refer_progress_notification_alloc().

refer_progress_notify()

static int refer_progress_notify ( void *  data )

static

Serialized callback for subscription notification.

Locking and serialization:

Although refer_progress_notify() always runs in the progress serializer, the pjproject evsub module itself can cause the subscription to be destroyed which then triggers refer_progress_on_evsub_state() to clean it up. In this case, it's possible that refer_progress_notify() could get the subscription pulled out from under it while it's trying to use it.

At one point we tried to have refer_progress_on_evsub_state() push the cleanup to the serializer and wait for its return before returning to pjproject but since pjproject calls its state callbacks with the dialog locked, this required us to unlock the dialog while waiting for the serialized cleanup, then lock it again before returning to pjproject. There were also still some cases where other callers of refer_progress_notify() weren't using the serializer and crashes were resulting.

Although all callers of refer_progress_notify() now use the progress serializer, we decided to simplify the locking so we didn't have to unlock and relock the dialog in refer_progress_on_evsub_state().

Now, refer_progress_notify() holds the dialog lock for all its work rather than just when calling pjsip_evsub_set_mod_data() to clear the module data. Since pjproject also holds the dialog lock while calling refer_progress_on_evsub_state(), there should be no more chances for the subscription to be cleaned up while still being used to send NOTIFYs.

Definition at line 145 of file res_pjsip_refer.c.

{
    RAII_VAR(struct refer_progress_notification *, notification, data, ao2_cleanup);
    pjsip_evsub *sub;
    pjsip_tx_data *tdata;
 
    pjsip_dlg_inc_lock(notification->progress->dlg);
 
    /* If the subscription has already been terminated we can't send a notification */
    if (!(sub = notification->progress->sub)) {
        ast_debug(3, "Not sending NOTIFY of response '%d' and state '%u' on progress monitor '%p' as subscription has been terminated\n",
            notification->response, notification->state, notification->progress);
        pjsip_dlg_dec_lock(notification->progress->dlg);
        return 0;
    }
 
    /* Send a deferred initial 100 Trying SIP frag NOTIFY if we haven't already. */
    if (!notification->progress->sent_100) {
        notification->progress->sent_100 = 1;
        if (notification->response != 100) {
            ast_debug(3, "Sending initial 100 Trying NOTIFY for progress monitor '%p'\n",
                notification->progress);
            if (pjsip_xfer_notify(sub, PJSIP_EVSUB_STATE_ACTIVE, 100, NULL, &tdata) == PJ_SUCCESS) {
                pjsip_xfer_send_request(sub, tdata);
            }
        }
    }
 
    ast_debug(3, "Sending NOTIFY with response '%d' and state '%u' on subscription '%p' and progress monitor '%p'\n",
        notification->response, notification->state, sub, notification->progress);
 
    /* Actually send the notification */
    if (pjsip_xfer_notify(sub, notification->state, notification->response, NULL, &tdata) == PJ_SUCCESS) {
        pjsip_xfer_send_request(sub, tdata);
    }
 
    pjsip_dlg_dec_lock(notification->progress->dlg);
 
    return 0;
}

References ao2_cleanup, ast_debug, NULL, RAII_VAR, and sub.

Referenced by refer_attended_task(), refer_blind_callback(), refer_incoming_refer_request(), refer_progress_bridge(), refer_progress_framehook(), and refer_progress_framehook_destroy().

refer_progress_on_evsub_state()

static void refer_progress_on_evsub_state ( pjsip_evsub *  sub, pjsip_event *  event  )

static

Callback for REFER subscription state changes.

See also

refer_progress_notify

The documentation attached to refer_progress_notify has more information about the locking issues with cleaning up the subscription.

Note

pjproject holds the dialog lock while calling this function.

Definition at line 328 of file res_pjsip_refer.c.

{
    struct refer_progress *progress = pjsip_evsub_get_mod_data(sub, refer_progress_module.id);
 
    /*
     * If being destroyed, remove the progress object from the subscription
     * and release the reference it had.
     */
    if (progress && (pjsip_evsub_get_state(sub) == PJSIP_EVSUB_STATE_TERMINATED)) {
        pjsip_evsub_set_mod_data(progress->sub, refer_progress_module.id, NULL);
        progress->sub = NULL;
        ao2_cleanup(progress);
    }
}

References ao2_cleanup, NULL, refer_progress_module, and sub.

refer_send()

static int refer_send ( void *  data )

static

Definition at line 1220 of file res_pjsip_refer.c.

{
    struct refer_data *rdata = data; /* The caller holds a reference */
    pjsip_tx_data *tdata;
    pjsip_evsub *sub;
    pj_str_t tmp;
    char refer_to_str[PJSIP_MAX_URL_SIZE];
    char disp_name_escaped[128];
    struct refer_out_of_dialog *refer;
    struct pjsip_evsub_user xfer_cb;
    RAII_VAR(char *, uri, NULL, ast_free);
    RAII_VAR(char *, tmp_str, NULL, ast_free);
    RAII_VAR(char *, display_name, NULL, ast_free);
    RAII_VAR(struct ast_sip_endpoint *, endpoint, NULL, ao2_cleanup);
    RAII_VAR(struct ast_sip_endpoint *, refer_to_endpoint, NULL, ao2_cleanup);
 
    endpoint = ast_sip_get_endpoint(rdata->destination, 1, &uri);
    if (!endpoint) {
        ast_log(LOG_ERROR,
            "PJSIP REFER - Could not find endpoint '%s' and no default outbound endpoint configured\n",
            rdata->destination);
        return -1;
    }
    ast_debug(3, "Request URI: %s\n", uri);
 
    refer_to_endpoint = ast_sip_get_endpoint(rdata->refer_to, 0, &tmp_str);
    if (!tmp_str) {
        ast_log(LOG_WARNING, "PJSIP REFER - Refer to not a valid resource identifier or SIP URI\n");
        return -1;
    }
    if (!(refer = ao2_alloc(sizeof(struct refer_out_of_dialog), refer_out_of_dialog_destroy))) {
        ast_log(LOG_ERROR, "PJSIP REFER - Could not allocate resources.\n");
        return -1;
    }
    /* The dialog will be terminated in the subscription event callback
     * when the subscription has terminated. */
    refer->authentication_challenge_count = 0;
    refer->dlg = ast_sip_create_dialog_uac(endpoint, uri, NULL);
    if (!refer->dlg) {
        ast_log(LOG_WARNING, "PJSIP REFER - Could not create dialog\n");
        ao2_cleanup(refer);
        return -1;
    }
    ast_sip_dialog_set_endpoint(refer->dlg, endpoint);
 
    pj_bzero(&xfer_cb, sizeof(xfer_cb));
    xfer_cb.on_evsub_state = &refer_client_on_evsub_state;
    if (pjsip_xfer_create_uac(refer->dlg, &xfer_cb, &sub) != PJ_SUCCESS) {
        ast_log(LOG_WARNING, "PJSIP REFER - Could not create uac\n");
        ao2_cleanup(refer);
        return -1;
    }
 
    display_name = ast_refer_get_var_and_unlink(rdata->refer, "display_name");
    if (display_name) {
        ast_escape_quoted(display_name, disp_name_escaped, sizeof(disp_name_escaped));
        snprintf(refer_to_str, sizeof(refer_to_str), "\"%s\" <%s>", disp_name_escaped, tmp_str);
    } else {
        snprintf(refer_to_str, sizeof(refer_to_str), "%s", tmp_str);
    }
 
    /* refer_out_of_dialog_module requires a reference to dlg
     * which will be released in refer_client_on_evsub_state()
     * when the implicit REFER subscription terminates */
    pjsip_evsub_set_mod_data(sub, refer_out_of_dialog_module.id, refer);
    if (pjsip_xfer_initiate(sub, pj_cstr(&tmp, refer_to_str), &tdata) != PJ_SUCCESS) {
        ast_log(LOG_WARNING, "PJSIP REFER - Could not create request\n");
        goto failure;
    }
 
    if (refer_to_endpoint && rdata->to_self) {
        pjsip_dlg_add_usage(refer->dlg, &refer_out_of_dialog_module, rdata);
    }
 
    ast_sip_update_to_uri(tdata, uri);
    ast_sip_update_from(tdata, rdata->from);
 
    /*
     * This copies any headers found in the refer's variables to
     * tdata.
     */
    vars_to_headers(rdata->refer, tdata);
    ast_debug(1, "Sending REFER to '%s' (via endpoint %s) from '%s'\n",
        rdata->destination, ast_sorcery_object_get_id(endpoint), rdata->from);
 
    if (pjsip_xfer_send_request(sub, tdata) == PJ_SUCCESS) {
        return 0;
    }
 
failure:
    ao2_cleanup(refer);
    pjsip_evsub_set_mod_data(sub, refer_out_of_dialog_module.id, NULL);
    pjsip_evsub_terminate(sub, PJ_FALSE);
    return -1;
}

References ao2_alloc, ao2_cleanup, ast_debug, ast_escape_quoted(), ast_free, ast_log, ast_refer_get_var_and_unlink(), ast_sip_create_dialog_uac(), ast_sip_dialog_set_endpoint(), ast_sip_get_endpoint(), ast_sip_update_from(), ast_sip_update_to_uri(), ast_sorcery_object_get_id(), refer_out_of_dialog::authentication_challenge_count, refer_data::destination, refer_out_of_dialog::dlg, refer_data::from, LOG_ERROR, LOG_WARNING, NULL, RAII_VAR, refer_data::refer, refer_client_on_evsub_state(), refer_out_of_dialog_destroy(), refer_out_of_dialog_module, refer_data::refer_to, sub, tmp(), refer_data::to_self, and vars_to_headers().

Referenced by sip_refer_send().

refer_unreference_dialog()

static int refer_unreference_dialog ( void *  obj )

static

Definition at line 1050 of file res_pjsip_refer.c.

{
    struct refer_out_of_dialog *data = obj;
 
    /* This is why we keep the dialog on the subscription. When the subscription
     * is destroyed, there is no guarantee that the underlying dialog is ready
     * to be destroyed. Furthermore, there's no guarantee in the opposite direction
     * either. The dialog could be destroyed before our subscription is. We fix
     * this problem by keeping a reference to the dialog until it is time to
     * destroy the subscription.
     */
    pjsip_dlg_dec_session(data->dlg, &refer_out_of_dialog_module);
    data->dlg = NULL;
 
    return 0;
}

References refer_out_of_dialog::dlg, NULL, and refer_out_of_dialog_module.

Referenced by refer_out_of_dialog_destroy().

session_end_if_deferred_task()

static int session_end_if_deferred_task ( void *  data )

static

Definition at line 507 of file res_pjsip_refer.c.

{
    struct ast_sip_session *session = data;
 
    ast_sip_session_end_if_deferred(session);
    ao2_ref(session, -1);
    return 0;
}

References ao2_ref, ast_sip_session_end_if_deferred(), and session.

Referenced by refer_attended_task().

sip_refer_send()

static int sip_refer_send ( const struct ast_refer *  refer )

static

Definition at line 1316 of file res_pjsip_refer.c.

{
    struct refer_data *rdata;
    int res;
 
    if (ast_strlen_zero(ast_refer_get_to(refer))) {
        ast_log(LOG_ERROR, "SIP REFER - a 'To' URI  must be specified\n");
        return -1;
    }
 
    rdata = refer_data_create(refer);
    if (!rdata) {
        return -1;
    }
 
    res = ast_sip_push_task_wait_serializer(refer_serializer, refer_send, rdata);
    ao2_ref(rdata, -1);
 
    return res;
}

References ao2_ref, ast_log, ast_refer_get_to(), ast_sip_push_task_wait_serializer(), ast_strlen_zero(), LOG_ERROR, refer_data::refer, refer_data_create(), refer_send(), and refer_serializer.

unload_module()

static int unload_module ( void  )

static

Definition at line 1849 of file res_pjsip_refer.c.

{
    ast_sip_session_unregister_supplement(&refer_supplement);
    ast_sip_unregister_service(&refer_out_of_dialog_module);
    ast_sip_unregister_service(&refer_progress_module);
    ast_taskprocessor_unreference(refer_serializer);
 
    return 0;
}

References ast_sip_session_unregister_supplement(), ast_sip_unregister_service(), ast_taskprocessor_unreference(), refer_out_of_dialog_module, refer_progress_module, refer_serializer, and refer_supplement.

vars_to_headers()

static enum pjsip_status_code vars_to_headers ( const struct ast_refer *  refer, pjsip_tx_data *  tdata  )

static

Definition at line 967 of file res_pjsip_refer.c.

{
    const char *name;
    const char *value;
    struct ast_refer_var_iterator *iter;
 
    for (iter = ast_refer_var_iterator_init(refer);
        ast_refer_var_iterator_next(iter, &name, &value);
        ast_refer_var_unref_current(iter)) {
        if (!is_refer_var_blocked(name)) {
            ast_sip_add_header(tdata, name, value);
        }
    }
    ast_refer_var_iterator_destroy(iter);
 
    return PJSIP_SC_OK;
}

References ast_refer_var_iterator_destroy(), ast_refer_var_iterator_init(), ast_refer_var_iterator_next(), ast_refer_var_unref_current(), ast_sip_add_header(), is_refer_var_blocked(), ast_refer_var_iterator::iter, name, and value.

Referenced by refer_send().

xfer_response_code2sip()

static int xfer_response_code2sip ( enum ast_transfer_result  xfer_code )

static

Definition at line 535 of file res_pjsip_refer.c.

{
    int response;
 
    response = 503;
    switch (xfer_code) {
    case AST_BRIDGE_TRANSFER_INVALID:
        response = 400;
        break;
    case AST_BRIDGE_TRANSFER_NOT_PERMITTED:
        response = 403;
        break;
    case AST_BRIDGE_TRANSFER_FAIL:
        response = 500;
        break;
    case AST_BRIDGE_TRANSFER_SUCCESS:
        response = 200;
        break;
    }
    return response;
}

References AST_BRIDGE_TRANSFER_FAIL, AST_BRIDGE_TRANSFER_INVALID, AST_BRIDGE_TRANSFER_NOT_PERMITTED, and AST_BRIDGE_TRANSFER_SUCCESS.

Referenced by refer_attended_task(), refer_incoming_attended_request(), and refer_incoming_blind_request().

Variable Documentation

__mod_info

struct ast_module_info __mod_info = { .name = AST_MODULE, .flags = AST_MODFLAG_LOAD_ORDER , .description = "PJSIP Blind and Attended Transfer Support" , .key = "This paragraph is copyright (c) 2006 by Digium, Inc. \In order for your module to load, it must return this \key via a function called \"key\". Any code which \includes this paragraph must be licensed under the GNU \General Public License version 2 or later (at your \option). In addition to Digium's general reservations \of rights, Digium expressly reserves the right to \allow other parties to license this paragraph under \different terms. Any use of Digium, Inc. trademarks or \logos (including \"Asterisk\" or \"Digium\") without \express written permission of Digium, Inc. is prohibited.\n" , .buildopt_sum = AST_BUILDOPT_SUM, .support_level = AST_MODULE_SUPPORT_CORE, .load = load_module, .unload = unload_module, .load_pri = AST_MODPRI_APP_DEPEND, .requires = "res_pjsip,res_pjsip_session,res_pjsip_pubsub", }

static

Definition at line 1865 of file res_pjsip_refer.c.

ast_module_info

const struct ast_module_info* ast_module_info = &__mod_info

static

Definition at line 1865 of file res_pjsip_refer.c.

refer_out_of_dialog_module

pjsip_module refer_out_of_dialog_module

static

REFER Out-of-dialog module, used to attach session data structure to subscription.

Definition at line 991 of file res_pjsip_refer.c.

Referenced by load_module(), refer_client_on_evsub_state(), refer_on_tx_request(), refer_send(), refer_unreference_dialog(), and unload_module().

refer_progress_evsub_cb

pjsip_evsub_user refer_progress_evsub_cb

static

Initial value:

= {
    .on_evsub_state = refer_progress_on_evsub_state,
}

Callback structure for subscription.

Definition at line 344 of file res_pjsip_refer.c.

Referenced by refer_progress_alloc().

refer_progress_module

pjsip_module refer_progress_module

static

Initial value:

= {
    .name = { "REFER Progress", 14 },
    .id = -1,
}

REFER Progress module, used to attach REFER progress structure to subscriptions.

Definition at line 85 of file res_pjsip_refer.c.

Referenced by dlg_releaser_task(), load_module(), refer_progress_alloc(), refer_progress_destroy(), refer_progress_on_evsub_state(), and unload_module().

refer_serializer

struct ast_taskprocessor* refer_serializer

static

Definition at line 44 of file res_pjsip_refer.c.

Referenced by load_module(), refer_out_of_dialog_destroy(), sip_refer_send(), and unload_module().

refer_supplement

struct ast_sip_session_supplement refer_supplement

static

Initial value:

= {
    .priority = AST_SIP_SUPPLEMENT_PRIORITY_CHANNEL + 1,
    .incoming_request = refer_incoming_request,
    .outgoing_request = refer_outgoing_request,
}

Definition at line 1813 of file res_pjsip_refer.c.

Referenced by load_module(), and unload_module().

refer_tech

const struct ast_refer_tech refer_tech

static

Initial value:

= {
    .name = "pjsip",
    .refer_send = sip_refer_send,
}

Definition at line 1337 of file res_pjsip_refer.c.

Referenced by ast_refer_send(), and load_module().