This backs out item 4 of the 4875e5ac32
commit. Item 4 added the t38_bye_supplement. Unfortunately, the frame
that it puts into the bridge may or may not be processed by the time the
bridged peer is kicked out of the bridge. If it is processed then all is
well. However, if it is not processed then that channel is stuck in fax
mode until it hangs up or maybe if it joins another bridge for T.38
faxing.
ASTERISK-25582
Change-Id: Ib20a03ecadf1bf8a0dcadfadf6c2f2e60919a9f7
947 lines
32 KiB
C
947 lines
32 KiB
C
/*
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* Asterisk -- An open source telephony toolkit.
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*
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* Copyright (C) 2013, Digium, Inc.
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*
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* Joshua Colp <jcolp@digium.com>
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*
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* See http://www.asterisk.org for more information about
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* the Asterisk project. Please do not directly contact
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* any of the maintainers of this project for assistance;
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* the project provides a web site, mailing lists and IRC
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* channels for your use.
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*
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* This program is free software, distributed under the terms of
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* the GNU General Public License Version 2. See the LICENSE file
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* at the top of the source tree.
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*/
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/*! \file
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*
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* \author Joshua Colp <jcolp@digium.com>
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*
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* \brief SIP T.38 handling
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*/
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/*** MODULEINFO
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<depend>pjproject</depend>
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<depend>res_pjsip</depend>
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<depend>res_pjsip_session</depend>
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<support_level>core</support_level>
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***/
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#include "asterisk.h"
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#include <pjsip.h>
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#include <pjsip_ua.h>
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#include <pjmedia.h>
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#include <pjlib.h>
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ASTERISK_REGISTER_FILE()
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#include "asterisk/module.h"
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#include "asterisk/udptl.h"
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#include "asterisk/netsock2.h"
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#include "asterisk/channel.h"
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#include "asterisk/acl.h"
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#include "asterisk/res_pjsip.h"
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#include "asterisk/res_pjsip_session.h"
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/*! \brief The number of seconds after receiving a T.38 re-invite before automatically rejecting it */
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#define T38_AUTOMATIC_REJECTION_SECONDS 5
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/*! \brief Address for IPv4 UDPTL */
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static struct ast_sockaddr address_ipv4;
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/*! \brief Address for IPv6 UDPTL */
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static struct ast_sockaddr address_ipv6;
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/*! \brief T.38 state information */
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struct t38_state {
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/*! \brief Current state */
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enum ast_sip_session_t38state state;
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/*! \brief Our T.38 parameters */
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struct ast_control_t38_parameters our_parms;
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/*! \brief Their T.38 parameters */
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struct ast_control_t38_parameters their_parms;
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/*! \brief Timer entry for automatically rejecting an inbound re-invite */
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pj_timer_entry timer;
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};
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/*! \brief Destructor for T.38 state information */
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static void t38_state_destroy(void *obj)
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{
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ast_free(obj);
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}
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/*! \brief Datastore for attaching T.38 state information */
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static const struct ast_datastore_info t38_datastore = {
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.type = "t38",
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.destroy = t38_state_destroy,
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};
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/*! \brief Structure for T.38 parameters task data */
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struct t38_parameters_task_data {
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/*! \brief Session itself */
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struct ast_sip_session *session;
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/*! \brief T.38 control frame */
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struct ast_frame *frame;
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};
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/*! \brief Destructor for T.38 data */
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static void t38_parameters_task_data_destroy(void *obj)
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{
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struct t38_parameters_task_data *data = obj;
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ao2_cleanup(data->session);
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if (data->frame) {
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ast_frfree(data->frame);
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}
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}
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/*! \brief Allocator for T.38 data */
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static struct t38_parameters_task_data *t38_parameters_task_data_alloc(struct ast_sip_session *session,
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struct ast_frame *frame)
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{
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struct t38_parameters_task_data *data = ao2_alloc(sizeof(*data), t38_parameters_task_data_destroy);
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if (!data) {
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return NULL;
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}
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data->session = session;
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ao2_ref(session, +1);
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data->frame = ast_frdup(frame);
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if (!data->frame) {
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ao2_ref(data, -1);
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data = NULL;
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}
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return data;
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}
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/*! \brief Helper function for changing the T.38 state */
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static void t38_change_state(struct ast_sip_session *session, struct ast_sip_session_media *session_media,
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struct t38_state *state, enum ast_sip_session_t38state new_state)
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{
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enum ast_sip_session_t38state old_state = session->t38state;
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struct ast_control_t38_parameters parameters = { .request_response = 0, };
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pj_time_val delay = { .sec = T38_AUTOMATIC_REJECTION_SECONDS };
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if (old_state == new_state) {
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return;
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}
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session->t38state = new_state;
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ast_debug(2, "T.38 state changed to '%u' from '%u' on channel '%s'\n",
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new_state, old_state,
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session->channel ? ast_channel_name(session->channel) : "<gone>");
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if (pj_timer_heap_cancel(pjsip_endpt_get_timer_heap(ast_sip_get_pjsip_endpoint()), &state->timer)) {
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ast_debug(2, "Automatic T.38 rejection on channel '%s' terminated\n",
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session->channel ? ast_channel_name(session->channel) : "<gone>");
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ao2_ref(session, -1);
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}
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if (!session->channel) {
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return;
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}
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switch (new_state) {
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case T38_PEER_REINVITE:
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ao2_ref(session, +1);
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if (pjsip_endpt_schedule_timer(ast_sip_get_pjsip_endpoint(), &state->timer, &delay) != PJ_SUCCESS) {
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ast_log(LOG_WARNING, "Scheduling of automatic T.38 rejection for channel '%s' failed\n",
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ast_channel_name(session->channel));
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ao2_ref(session, -1);
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}
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parameters = state->their_parms;
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parameters.max_ifp = ast_udptl_get_far_max_ifp(session_media->udptl);
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parameters.request_response = AST_T38_REQUEST_NEGOTIATE;
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ast_udptl_set_tag(session_media->udptl, "%s", ast_channel_name(session->channel));
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/* Inform the bridge the channel is in that it needs to be reconfigured */
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ast_channel_set_unbridged(session->channel, 1);
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break;
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case T38_ENABLED:
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parameters = state->their_parms;
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parameters.max_ifp = ast_udptl_get_far_max_ifp(session_media->udptl);
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parameters.request_response = AST_T38_NEGOTIATED;
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ast_udptl_set_tag(session_media->udptl, "%s", ast_channel_name(session->channel));
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break;
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case T38_REJECTED:
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case T38_DISABLED:
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if (old_state == T38_ENABLED) {
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parameters.request_response = AST_T38_TERMINATED;
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} else if (old_state == T38_LOCAL_REINVITE) {
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parameters.request_response = AST_T38_REFUSED;
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}
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break;
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case T38_LOCAL_REINVITE:
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/* Inform the bridge the channel is in that it needs to be reconfigured */
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ast_channel_set_unbridged(session->channel, 1);
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break;
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case T38_MAX_ENUM:
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/* Well, that shouldn't happen */
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ast_assert(0);
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break;
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}
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if (parameters.request_response) {
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ast_queue_control_data(session->channel, AST_CONTROL_T38_PARAMETERS, ¶meters, sizeof(parameters));
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}
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}
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/*! \brief Task function which rejects a T.38 re-invite and resumes handling it */
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static int t38_automatic_reject(void *obj)
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{
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RAII_VAR(struct ast_sip_session *, session, obj, ao2_cleanup);
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RAII_VAR(struct ast_datastore *, datastore, ast_sip_session_get_datastore(session, "t38"), ao2_cleanup);
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RAII_VAR(struct ast_sip_session_media *, session_media, ao2_find(session->media, "image", OBJ_KEY), ao2_cleanup);
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if (!datastore) {
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return 0;
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}
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ast_debug(2, "Automatically rejecting T.38 request on channel '%s'\n",
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session->channel ? ast_channel_name(session->channel) : "<gone>");
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t38_change_state(session, session_media, datastore->data, T38_REJECTED);
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ast_sip_session_resume_reinvite(session);
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return 0;
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}
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/*! \brief Timer entry callback which queues a task to reject a T.38 re-invite and resume handling it */
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static void t38_automatic_reject_timer_cb(pj_timer_heap_t *timer_heap, struct pj_timer_entry *entry)
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{
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struct ast_sip_session *session = entry->user_data;
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if (ast_sip_push_task(session->serializer, t38_automatic_reject, session)) {
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ao2_ref(session, -1);
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}
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}
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/*! \brief Helper function which retrieves or allocates a T.38 state information datastore */
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static struct t38_state *t38_state_get_or_alloc(struct ast_sip_session *session)
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{
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RAII_VAR(struct ast_datastore *, datastore, ast_sip_session_get_datastore(session, "t38"), ao2_cleanup);
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struct t38_state *state;
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/* While the datastore refcount is decremented this is operating in the serializer so it will remain valid regardless */
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if (datastore) {
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return datastore->data;
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}
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if (!(datastore = ast_sip_session_alloc_datastore(&t38_datastore, "t38"))
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|| !(datastore->data = ast_calloc(1, sizeof(struct t38_state)))
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|| ast_sip_session_add_datastore(session, datastore)) {
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return NULL;
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}
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state = datastore->data;
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/* This will get bumped up before scheduling */
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state->timer.user_data = session;
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state->timer.cb = t38_automatic_reject_timer_cb;
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datastore->data = state;
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return state;
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}
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/*! \brief Initializes UDPTL support on a session, only done when actually needed */
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static int t38_initialize_session(struct ast_sip_session *session, struct ast_sip_session_media *session_media)
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{
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if (session_media->udptl) {
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return 0;
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}
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if (!(session_media->udptl = ast_udptl_new_with_bindaddr(NULL, NULL, 0,
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session->endpoint->media.t38.ipv6 ? &address_ipv6 : &address_ipv4))) {
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return -1;
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}
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ast_channel_set_fd(session->channel, 5, ast_udptl_fd(session_media->udptl));
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ast_udptl_set_error_correction_scheme(session_media->udptl, session->endpoint->media.t38.error_correction);
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ast_udptl_setnat(session_media->udptl, session->endpoint->media.t38.nat);
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ast_udptl_set_far_max_datagram(session_media->udptl, session->endpoint->media.t38.maxdatagram);
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ast_debug(3, "UDPTL initialized on session for %s\n", ast_channel_name(session->channel));
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return 0;
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}
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/*! \brief Callback for when T.38 reinvite SDP is created */
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static int t38_reinvite_sdp_cb(struct ast_sip_session *session, pjmedia_sdp_session *sdp)
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{
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int stream;
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/* Move the image media stream to the front and have it as the only stream, pjmedia will fill in
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* dummy streams for the rest
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*/
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for (stream = 0; stream < sdp->media_count++; ++stream) {
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if (!pj_strcmp2(&sdp->media[stream]->desc.media, "image")) {
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sdp->media[0] = sdp->media[stream];
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sdp->media_count = 1;
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break;
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}
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}
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return 0;
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}
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/*! \brief Callback for when a response is received for a T.38 re-invite */
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static int t38_reinvite_response_cb(struct ast_sip_session *session, pjsip_rx_data *rdata)
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{
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struct pjsip_status_line status = rdata->msg_info.msg->line.status;
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struct t38_state *state;
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RAII_VAR(struct ast_sip_session_media *, session_media, NULL, ao2_cleanup);
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if (status.code == 100) {
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return 0;
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}
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if (!(state = t38_state_get_or_alloc(session)) ||
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!(session_media = ao2_find(session->media, "image", OBJ_KEY))) {
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ast_log(LOG_WARNING, "Received response to T.38 re-invite on '%s' but state unavailable\n",
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ast_channel_name(session->channel));
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return 0;
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}
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t38_change_state(session, session_media, state, (status.code == 200) ? T38_ENABLED : T38_REJECTED);
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return 0;
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}
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/*! \brief Task for reacting to T.38 control frame */
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static int t38_interpret_parameters(void *obj)
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{
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RAII_VAR(struct t38_parameters_task_data *, data, obj, ao2_cleanup);
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const struct ast_control_t38_parameters *parameters = data->frame->data.ptr;
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struct t38_state *state = t38_state_get_or_alloc(data->session);
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RAII_VAR(struct ast_sip_session_media *, session_media, ao2_find(data->session->media, "image", OBJ_KEY), ao2_cleanup);
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/* Without session media or state we can't interpret parameters */
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if (!session_media || !state) {
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return 0;
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}
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switch (parameters->request_response) {
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case AST_T38_NEGOTIATED:
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case AST_T38_REQUEST_NEGOTIATE: /* Request T38 */
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/* Negotiation can not take place without a valid max_ifp value. */
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if (!parameters->max_ifp) {
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if (data->session->t38state == T38_PEER_REINVITE) {
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t38_change_state(data->session, session_media, state, T38_REJECTED);
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ast_sip_session_resume_reinvite(data->session);
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} else if (data->session->t38state == T38_ENABLED) {
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t38_change_state(data->session, session_media, state, T38_DISABLED);
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ast_sip_session_refresh(data->session, NULL, NULL, NULL,
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AST_SIP_SESSION_REFRESH_METHOD_INVITE, 1);
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}
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break;
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} else if (data->session->t38state == T38_PEER_REINVITE) {
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state->our_parms = *parameters;
|
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/* modify our parameters to conform to the peer's parameters,
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* based on the rules in the ITU T.38 recommendation
|
|
*/
|
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if (!state->their_parms.fill_bit_removal) {
|
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state->our_parms.fill_bit_removal = 0;
|
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}
|
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if (!state->their_parms.transcoding_mmr) {
|
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state->our_parms.transcoding_mmr = 0;
|
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}
|
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if (!state->their_parms.transcoding_jbig) {
|
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state->our_parms.transcoding_jbig = 0;
|
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}
|
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state->our_parms.version = MIN(state->our_parms.version, state->their_parms.version);
|
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state->our_parms.rate_management = state->their_parms.rate_management;
|
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ast_udptl_set_local_max_ifp(session_media->udptl, state->our_parms.max_ifp);
|
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t38_change_state(data->session, session_media, state, T38_ENABLED);
|
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ast_sip_session_resume_reinvite(data->session);
|
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} else if (data->session->t38state != T38_ENABLED) {
|
|
if (t38_initialize_session(data->session, session_media)) {
|
|
break;
|
|
}
|
|
state->our_parms = *parameters;
|
|
ast_udptl_set_local_max_ifp(session_media->udptl, state->our_parms.max_ifp);
|
|
t38_change_state(data->session, session_media, state, T38_LOCAL_REINVITE);
|
|
ast_sip_session_refresh(data->session, NULL, t38_reinvite_sdp_cb, t38_reinvite_response_cb,
|
|
AST_SIP_SESSION_REFRESH_METHOD_INVITE, 1);
|
|
}
|
|
break;
|
|
case AST_T38_TERMINATED:
|
|
case AST_T38_REFUSED:
|
|
case AST_T38_REQUEST_TERMINATE: /* Shutdown T38 */
|
|
if (data->session->t38state == T38_PEER_REINVITE) {
|
|
t38_change_state(data->session, session_media, state, T38_REJECTED);
|
|
ast_sip_session_resume_reinvite(data->session);
|
|
} else if (data->session->t38state == T38_ENABLED) {
|
|
t38_change_state(data->session, session_media, state, T38_DISABLED);
|
|
ast_sip_session_refresh(data->session, NULL, NULL, NULL, AST_SIP_SESSION_REFRESH_METHOD_INVITE, 1);
|
|
}
|
|
break;
|
|
case AST_T38_REQUEST_PARMS: { /* Application wants remote's parameters re-sent */
|
|
struct ast_control_t38_parameters parameters = state->their_parms;
|
|
|
|
if (data->session->t38state == T38_PEER_REINVITE) {
|
|
parameters.max_ifp = ast_udptl_get_far_max_ifp(session_media->udptl);
|
|
parameters.request_response = AST_T38_REQUEST_NEGOTIATE;
|
|
ast_queue_control_data(data->session->channel, AST_CONTROL_T38_PARAMETERS, ¶meters, sizeof(parameters));
|
|
}
|
|
break;
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*! \brief Frame hook callback for writing */
|
|
static struct ast_frame *t38_framehook_write(struct ast_sip_session *session, struct ast_frame *f)
|
|
{
|
|
if (f->frametype == AST_FRAME_CONTROL && f->subclass.integer == AST_CONTROL_T38_PARAMETERS &&
|
|
session->endpoint->media.t38.enabled) {
|
|
struct t38_parameters_task_data *data = t38_parameters_task_data_alloc(session, f);
|
|
|
|
if (!data) {
|
|
return f;
|
|
}
|
|
|
|
if (ast_sip_push_task(session->serializer, t38_interpret_parameters, data)) {
|
|
ao2_ref(data, -1);
|
|
}
|
|
} else if (f->frametype == AST_FRAME_MODEM) {
|
|
RAII_VAR(struct ast_sip_session_media *, session_media, NULL, ao2_cleanup);
|
|
|
|
if ((session_media = ao2_find(session->media, "image", OBJ_KEY)) &&
|
|
session_media->udptl) {
|
|
ast_udptl_write(session_media->udptl, f);
|
|
}
|
|
}
|
|
|
|
return f;
|
|
}
|
|
|
|
/*! \brief Frame hook callback for reading */
|
|
static struct ast_frame *t38_framehook_read(struct ast_sip_session *session, struct ast_frame *f)
|
|
{
|
|
if (ast_channel_fdno(session->channel) == 5) {
|
|
RAII_VAR(struct ast_sip_session_media *, session_media, NULL, ao2_cleanup);
|
|
|
|
if ((session_media = ao2_find(session->media, "image", OBJ_KEY)) &&
|
|
session_media->udptl) {
|
|
f = ast_udptl_read(session_media->udptl);
|
|
}
|
|
}
|
|
|
|
return f;
|
|
}
|
|
|
|
/*! \brief Frame hook callback for T.38 related stuff */
|
|
static struct ast_frame *t38_framehook(struct ast_channel *chan, struct ast_frame *f,
|
|
enum ast_framehook_event event, void *data)
|
|
{
|
|
struct ast_sip_channel_pvt *channel = ast_channel_tech_pvt(chan);
|
|
|
|
if (event == AST_FRAMEHOOK_EVENT_READ) {
|
|
f = t38_framehook_read(channel->session, f);
|
|
} else if (event == AST_FRAMEHOOK_EVENT_WRITE) {
|
|
f = t38_framehook_write(channel->session, f);
|
|
}
|
|
|
|
return f;
|
|
}
|
|
|
|
static void t38_masq(void *data, int framehook_id,
|
|
struct ast_channel *old_chan, struct ast_channel *new_chan)
|
|
{
|
|
if (ast_channel_tech(old_chan) == ast_channel_tech(new_chan)) {
|
|
return;
|
|
}
|
|
|
|
/* This framehook is only applicable to PJSIP channels */
|
|
ast_framehook_detach(new_chan, framehook_id);
|
|
}
|
|
|
|
static int t38_consume(void *data, enum ast_frame_type type)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static const struct ast_datastore_info t38_framehook_datastore = {
|
|
.type = "T38 framehook",
|
|
};
|
|
|
|
/*! \brief Function called to attach T.38 framehook to channel when appropriate */
|
|
static void t38_attach_framehook(struct ast_sip_session *session)
|
|
{
|
|
int framehook_id;
|
|
struct ast_datastore *datastore = NULL;
|
|
static struct ast_framehook_interface hook = {
|
|
.version = AST_FRAMEHOOK_INTERFACE_VERSION,
|
|
.event_cb = t38_framehook,
|
|
.consume_cb = t38_consume,
|
|
.chan_fixup_cb = t38_masq,
|
|
.chan_breakdown_cb = t38_masq,
|
|
};
|
|
|
|
/* If the channel's already gone, bail */
|
|
if (!session->channel) {
|
|
return;
|
|
}
|
|
|
|
/* Only attach the framehook if t38 is enabled for the endpoint */
|
|
if (!session->endpoint->media.t38.enabled) {
|
|
return;
|
|
}
|
|
|
|
/* Skip attaching the framehook if the T.38 datastore already exists for the channel */
|
|
ast_channel_lock(session->channel);
|
|
if ((datastore = ast_channel_datastore_find(session->channel, &t38_framehook_datastore, NULL))) {
|
|
ast_channel_unlock(session->channel);
|
|
return;
|
|
}
|
|
ast_channel_unlock(session->channel);
|
|
|
|
framehook_id = ast_framehook_attach(session->channel, &hook);
|
|
if (framehook_id < 0) {
|
|
ast_log(LOG_WARNING, "Could not attach T.38 Frame hook to channel, T.38 will be unavailable on '%s'\n",
|
|
ast_channel_name(session->channel));
|
|
return;
|
|
}
|
|
|
|
ast_channel_lock(session->channel);
|
|
datastore = ast_datastore_alloc(&t38_framehook_datastore, NULL);
|
|
if (!datastore) {
|
|
ast_log(LOG_ERROR, "Could not attach T.38 Frame hook to channel, T.38 will be unavailable on '%s'\n",
|
|
ast_channel_name(session->channel));
|
|
ast_framehook_detach(session->channel, framehook_id);
|
|
ast_channel_unlock(session->channel);
|
|
return;
|
|
}
|
|
|
|
ast_channel_datastore_add(session->channel, datastore);
|
|
ast_channel_unlock(session->channel);
|
|
}
|
|
|
|
/*! \brief Function called when an INVITE arrives */
|
|
static int t38_incoming_invite_request(struct ast_sip_session *session, struct pjsip_rx_data *rdata)
|
|
{
|
|
t38_attach_framehook(session);
|
|
return 0;
|
|
}
|
|
|
|
/*! \brief Function called when an INVITE is sent */
|
|
static void t38_outgoing_invite_request(struct ast_sip_session *session, struct pjsip_tx_data *tdata)
|
|
{
|
|
t38_attach_framehook(session);
|
|
}
|
|
|
|
/*! \brief Get Max T.38 Transmission rate from T38 capabilities */
|
|
static unsigned int t38_get_rate(enum ast_control_t38_rate rate)
|
|
{
|
|
switch (rate) {
|
|
case AST_T38_RATE_2400:
|
|
return 2400;
|
|
case AST_T38_RATE_4800:
|
|
return 4800;
|
|
case AST_T38_RATE_7200:
|
|
return 7200;
|
|
case AST_T38_RATE_9600:
|
|
return 9600;
|
|
case AST_T38_RATE_12000:
|
|
return 12000;
|
|
case AST_T38_RATE_14400:
|
|
return 14400;
|
|
default:
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/*! \brief Supplement for adding framehook to session channel */
|
|
static struct ast_sip_session_supplement t38_supplement = {
|
|
.method = "INVITE",
|
|
.priority = AST_SIP_SUPPLEMENT_PRIORITY_CHANNEL + 1,
|
|
.incoming_request = t38_incoming_invite_request,
|
|
.outgoing_request = t38_outgoing_invite_request,
|
|
};
|
|
|
|
/*! \brief Parse a T.38 image stream and store the attribute information */
|
|
static void t38_interpret_sdp(struct t38_state *state, struct ast_sip_session *session, struct ast_sip_session_media *session_media,
|
|
const struct pjmedia_sdp_media *stream)
|
|
{
|
|
unsigned int attr_i;
|
|
|
|
for (attr_i = 0; attr_i < stream->attr_count; attr_i++) {
|
|
pjmedia_sdp_attr *attr = stream->attr[attr_i];
|
|
|
|
if (!pj_stricmp2(&attr->name, "t38faxmaxbuffer")) {
|
|
/* This is purposely left empty, it is unused */
|
|
} else if (!pj_stricmp2(&attr->name, "t38maxbitrate") || !pj_stricmp2(&attr->name, "t38faxmaxrate")) {
|
|
switch (pj_strtoul(&attr->value)) {
|
|
case 14400:
|
|
state->their_parms.rate = AST_T38_RATE_14400;
|
|
break;
|
|
case 12000:
|
|
state->their_parms.rate = AST_T38_RATE_12000;
|
|
break;
|
|
case 9600:
|
|
state->their_parms.rate = AST_T38_RATE_9600;
|
|
break;
|
|
case 7200:
|
|
state->their_parms.rate = AST_T38_RATE_7200;
|
|
break;
|
|
case 4800:
|
|
state->their_parms.rate = AST_T38_RATE_4800;
|
|
break;
|
|
case 2400:
|
|
state->their_parms.rate = AST_T38_RATE_2400;
|
|
break;
|
|
}
|
|
} else if (!pj_stricmp2(&attr->name, "t38faxversion")) {
|
|
state->their_parms.version = pj_strtoul(&attr->value);
|
|
} else if (!pj_stricmp2(&attr->name, "t38faxmaxdatagram") || !pj_stricmp2(&attr->name, "t38maxdatagram")) {
|
|
if (!session->endpoint->media.t38.maxdatagram) {
|
|
ast_udptl_set_far_max_datagram(session_media->udptl, pj_strtoul(&attr->value));
|
|
}
|
|
} else if (!pj_stricmp2(&attr->name, "t38faxfillbitremoval")) {
|
|
state->their_parms.fill_bit_removal = 1;
|
|
} else if (!pj_stricmp2(&attr->name, "t38faxtranscodingmmr")) {
|
|
state->their_parms.transcoding_mmr = 1;
|
|
} else if (!pj_stricmp2(&attr->name, "t38faxtranscodingjbig")) {
|
|
state->their_parms.transcoding_jbig = 1;
|
|
} else if (!pj_stricmp2(&attr->name, "t38faxratemanagement")) {
|
|
if (!pj_stricmp2(&attr->value, "localTCF")) {
|
|
state->their_parms.rate_management = AST_T38_RATE_MANAGEMENT_LOCAL_TCF;
|
|
} else if (!pj_stricmp2(&attr->value, "transferredTCF")) {
|
|
state->their_parms.rate_management = AST_T38_RATE_MANAGEMENT_TRANSFERRED_TCF;
|
|
}
|
|
} else if (!pj_stricmp2(&attr->name, "t38faxudpec")) {
|
|
if (!pj_stricmp2(&attr->value, "t38UDPRedundancy")) {
|
|
ast_udptl_set_error_correction_scheme(session_media->udptl, UDPTL_ERROR_CORRECTION_REDUNDANCY);
|
|
} else if (!pj_stricmp2(&attr->value, "t38UDPFEC")) {
|
|
ast_udptl_set_error_correction_scheme(session_media->udptl, UDPTL_ERROR_CORRECTION_FEC);
|
|
} else {
|
|
ast_udptl_set_error_correction_scheme(session_media->udptl, UDPTL_ERROR_CORRECTION_NONE);
|
|
}
|
|
}
|
|
|
|
}
|
|
}
|
|
|
|
/*! \brief Function which defers an incoming media stream */
|
|
static enum ast_sip_session_sdp_stream_defer defer_incoming_sdp_stream(
|
|
struct ast_sip_session *session, struct ast_sip_session_media *session_media,
|
|
const struct pjmedia_sdp_session *sdp, const struct pjmedia_sdp_media *stream)
|
|
{
|
|
struct t38_state *state;
|
|
|
|
if (!session->endpoint->media.t38.enabled) {
|
|
ast_debug(3, "Not deferring incoming SDP stream: T.38 not enabled on %s\n", ast_channel_name(session->channel));
|
|
return AST_SIP_SESSION_SDP_DEFER_NOT_HANDLED;
|
|
}
|
|
|
|
if (t38_initialize_session(session, session_media)) {
|
|
ast_debug(3, "Not deferring incoming SDP stream: Failed to initialize UDPTL on %s\n", ast_channel_name(session->channel));
|
|
return AST_SIP_SESSION_SDP_DEFER_ERROR;
|
|
}
|
|
|
|
if (!(state = t38_state_get_or_alloc(session))) {
|
|
return AST_SIP_SESSION_SDP_DEFER_ERROR;
|
|
}
|
|
|
|
t38_interpret_sdp(state, session, session_media, stream);
|
|
|
|
/* If they are initiating the re-invite we need to defer responding until later */
|
|
if (session->t38state == T38_DISABLED) {
|
|
t38_change_state(session, session_media, state, T38_PEER_REINVITE);
|
|
ast_debug(3, "Deferring incoming SDP stream on %s for peer re-invite\n", ast_channel_name(session->channel));
|
|
return AST_SIP_SESSION_SDP_DEFER_NEEDED;
|
|
}
|
|
|
|
return AST_SIP_SESSION_SDP_DEFER_NOT_NEEDED;
|
|
}
|
|
|
|
/*! \brief Function which negotiates an incoming media stream */
|
|
static int negotiate_incoming_sdp_stream(struct ast_sip_session *session, struct ast_sip_session_media *session_media,
|
|
const struct pjmedia_sdp_session *sdp, const struct pjmedia_sdp_media *stream)
|
|
{
|
|
struct t38_state *state;
|
|
char host[NI_MAXHOST];
|
|
RAII_VAR(struct ast_sockaddr *, addrs, NULL, ast_free);
|
|
|
|
if (!session->endpoint->media.t38.enabled) {
|
|
ast_debug(3, "Declining; T.38 not enabled on session\n");
|
|
return -1;
|
|
}
|
|
|
|
if (!(state = t38_state_get_or_alloc(session))) {
|
|
return -1;
|
|
}
|
|
|
|
if ((session->t38state == T38_REJECTED) || (session->t38state == T38_DISABLED)) {
|
|
ast_debug(3, "Declining; T.38 state is rejected or declined\n");
|
|
t38_change_state(session, session_media, state, T38_DISABLED);
|
|
return -1;
|
|
}
|
|
|
|
ast_copy_pj_str(host, stream->conn ? &stream->conn->addr : &sdp->conn->addr, sizeof(host));
|
|
|
|
/* Ensure that the address provided is valid */
|
|
if (ast_sockaddr_resolve(&addrs, host, PARSE_PORT_FORBID, AST_AF_INET) <= 0) {
|
|
/* The provided host was actually invalid so we error out this negotiation */
|
|
ast_debug(3, "Declining; provided host is invalid\n");
|
|
return -1;
|
|
}
|
|
|
|
/* Check the address family to make sure it matches configured */
|
|
if ((ast_sockaddr_is_ipv6(addrs) && !session->endpoint->media.t38.ipv6) ||
|
|
(ast_sockaddr_is_ipv4(addrs) && session->endpoint->media.t38.ipv6)) {
|
|
/* The address does not match configured */
|
|
ast_debug(3, "Declining, provided host does not match configured address family\n");
|
|
return -1;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
/*! \brief Function which creates an outgoing stream */
|
|
static int create_outgoing_sdp_stream(struct ast_sip_session *session, struct ast_sip_session_media *session_media,
|
|
struct pjmedia_sdp_session *sdp)
|
|
{
|
|
pj_pool_t *pool = session->inv_session->pool_prov;
|
|
static const pj_str_t STR_IN = { "IN", 2 };
|
|
static const pj_str_t STR_IP4 = { "IP4", 3};
|
|
static const pj_str_t STR_IP6 = { "IP6", 3};
|
|
static const pj_str_t STR_UDPTL = { "udptl", 5 };
|
|
static const pj_str_t STR_T38 = { "t38", 3 };
|
|
static const pj_str_t STR_TRANSFERREDTCF = { "transferredTCF", 14 };
|
|
static const pj_str_t STR_LOCALTCF = { "localTCF", 8 };
|
|
static const pj_str_t STR_T38UDPFEC = { "t38UDPFEC", 9 };
|
|
static const pj_str_t STR_T38UDPREDUNDANCY = { "t38UDPRedundancy", 16 };
|
|
struct t38_state *state;
|
|
pjmedia_sdp_media *media;
|
|
const char *hostip = NULL;
|
|
struct ast_sockaddr addr;
|
|
char tmp[512];
|
|
pj_str_t stmp;
|
|
|
|
if (!session->endpoint->media.t38.enabled) {
|
|
ast_debug(3, "Not creating outgoing SDP stream: T.38 not enabled\n");
|
|
return 1;
|
|
} else if ((session->t38state != T38_LOCAL_REINVITE) && (session->t38state != T38_PEER_REINVITE) &&
|
|
(session->t38state != T38_ENABLED)) {
|
|
ast_debug(3, "Not creating outgoing SDP stream: T.38 not enabled\n");
|
|
return 1;
|
|
} else if (!(state = t38_state_get_or_alloc(session))) {
|
|
return -1;
|
|
} else if (t38_initialize_session(session, session_media)) {
|
|
ast_debug(3, "Not creating outgoing SDP stream: Failed to initialize T.38 session\n");
|
|
return -1;
|
|
}
|
|
|
|
if (!(media = pj_pool_zalloc(pool, sizeof(struct pjmedia_sdp_media))) ||
|
|
!(media->conn = pj_pool_zalloc(pool, sizeof(struct pjmedia_sdp_conn)))) {
|
|
return -1;
|
|
}
|
|
|
|
media->desc.media = pj_str(session_media->stream_type);
|
|
media->desc.transport = STR_UDPTL;
|
|
|
|
if (ast_strlen_zero(session->endpoint->media.address)) {
|
|
hostip = ast_sip_get_host_ip_string(session->endpoint->media.t38.ipv6 ? pj_AF_INET6() : pj_AF_INET());
|
|
} else {
|
|
hostip = session->endpoint->media.address;
|
|
}
|
|
|
|
if (ast_strlen_zero(hostip)) {
|
|
ast_debug(3, "Not creating outgoing SDP stream: no known host IP\n");
|
|
return -1;
|
|
}
|
|
|
|
media->conn->net_type = STR_IN;
|
|
media->conn->addr_type = session->endpoint->media.t38.ipv6 ? STR_IP6 : STR_IP4;
|
|
pj_strdup2(pool, &media->conn->addr, hostip);
|
|
ast_udptl_get_us(session_media->udptl, &addr);
|
|
media->desc.port = (pj_uint16_t) ast_sockaddr_port(&addr);
|
|
media->desc.port_count = 1;
|
|
media->desc.fmt[media->desc.fmt_count++] = STR_T38;
|
|
|
|
snprintf(tmp, sizeof(tmp), "%u", state->our_parms.version);
|
|
media->attr[media->attr_count++] = pjmedia_sdp_attr_create(pool, "T38FaxVersion", pj_cstr(&stmp, tmp));
|
|
|
|
snprintf(tmp, sizeof(tmp), "%u", t38_get_rate(state->our_parms.rate));
|
|
media->attr[media->attr_count++] = pjmedia_sdp_attr_create(pool, "T38MaxBitRate", pj_cstr(&stmp, tmp));
|
|
|
|
if (state->our_parms.fill_bit_removal) {
|
|
media->attr[media->attr_count++] = pjmedia_sdp_attr_create(pool, "T38FaxFillBitRemoval", NULL);
|
|
}
|
|
|
|
if (state->our_parms.transcoding_mmr) {
|
|
media->attr[media->attr_count++] = pjmedia_sdp_attr_create(pool, "T38FaxTranscodingMMR", NULL);
|
|
}
|
|
|
|
if (state->our_parms.transcoding_jbig) {
|
|
media->attr[media->attr_count++] = pjmedia_sdp_attr_create(pool, "T38FaxTranscodingJBIG", NULL);
|
|
}
|
|
|
|
switch (state->our_parms.rate_management) {
|
|
case AST_T38_RATE_MANAGEMENT_TRANSFERRED_TCF:
|
|
media->attr[media->attr_count++] = pjmedia_sdp_attr_create(pool, "T38FaxRateManagement", &STR_TRANSFERREDTCF);
|
|
break;
|
|
case AST_T38_RATE_MANAGEMENT_LOCAL_TCF:
|
|
media->attr[media->attr_count++] = pjmedia_sdp_attr_create(pool, "T38FaxRateManagement", &STR_LOCALTCF);
|
|
break;
|
|
}
|
|
|
|
snprintf(tmp, sizeof(tmp), "%u", ast_udptl_get_local_max_datagram(session_media->udptl));
|
|
media->attr[media->attr_count++] = pjmedia_sdp_attr_create(pool, "T38FaxMaxDatagram", pj_cstr(&stmp, tmp));
|
|
|
|
switch (ast_udptl_get_error_correction_scheme(session_media->udptl)) {
|
|
case UDPTL_ERROR_CORRECTION_NONE:
|
|
break;
|
|
case UDPTL_ERROR_CORRECTION_FEC:
|
|
media->attr[media->attr_count++] = pjmedia_sdp_attr_create(pool, "T38FaxUdpEC", &STR_T38UDPFEC);
|
|
break;
|
|
case UDPTL_ERROR_CORRECTION_REDUNDANCY:
|
|
media->attr[media->attr_count++] = pjmedia_sdp_attr_create(pool, "T38FaxUdpEC", &STR_T38UDPREDUNDANCY);
|
|
break;
|
|
}
|
|
|
|
sdp->media[sdp->media_count++] = media;
|
|
|
|
return 1;
|
|
}
|
|
|
|
/*! \brief Function which applies a negotiated stream */
|
|
static int apply_negotiated_sdp_stream(struct ast_sip_session *session, struct ast_sip_session_media *session_media,
|
|
const struct pjmedia_sdp_session *local, const struct pjmedia_sdp_media *local_stream,
|
|
const struct pjmedia_sdp_session *remote, const struct pjmedia_sdp_media *remote_stream)
|
|
{
|
|
RAII_VAR(struct ast_sockaddr *, addrs, NULL, ast_free);
|
|
char host[NI_MAXHOST];
|
|
struct t38_state *state;
|
|
|
|
if (!session_media->udptl) {
|
|
ast_debug(3, "Not applying negotiated SDP stream: no UDTPL session\n");
|
|
return 0;
|
|
}
|
|
|
|
if (!(state = t38_state_get_or_alloc(session))) {
|
|
return -1;
|
|
}
|
|
|
|
ast_copy_pj_str(host, remote_stream->conn ? &remote_stream->conn->addr : &remote->conn->addr, sizeof(host));
|
|
|
|
/* Ensure that the address provided is valid */
|
|
if (ast_sockaddr_resolve(&addrs, host, PARSE_PORT_FORBID, AST_AF_UNSPEC) <= 0) {
|
|
/* The provided host was actually invalid so we error out this negotiation */
|
|
ast_debug(3, "Not applying negotiated SDP stream: failed to resolve remote stream host\n");
|
|
return -1;
|
|
}
|
|
|
|
ast_sockaddr_set_port(addrs, remote_stream->desc.port);
|
|
ast_udptl_set_peer(session_media->udptl, addrs);
|
|
|
|
t38_interpret_sdp(state, session, session_media, remote_stream);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*! \brief Function which updates the media stream with external media address, if applicable */
|
|
static void change_outgoing_sdp_stream_media_address(pjsip_tx_data *tdata, struct pjmedia_sdp_media *stream, struct ast_sip_transport *transport)
|
|
{
|
|
RAII_VAR(struct ast_sip_transport_state *, transport_state, ast_sip_get_transport_state(ast_sorcery_object_get_id(transport)), ao2_cleanup);
|
|
char host[NI_MAXHOST];
|
|
struct ast_sockaddr addr = { { 0, } };
|
|
|
|
/* If the stream has been rejected there will be no connection line */
|
|
if (!stream->conn || !transport_state) {
|
|
return;
|
|
}
|
|
|
|
ast_copy_pj_str(host, &stream->conn->addr, sizeof(host));
|
|
ast_sockaddr_parse(&addr, host, PARSE_PORT_FORBID);
|
|
|
|
/* Is the address within the SDP inside the same network? */
|
|
if (ast_apply_ha(transport_state->localnet, &addr) == AST_SENSE_ALLOW) {
|
|
return;
|
|
}
|
|
|
|
pj_strdup2(tdata->pool, &stream->conn->addr, transport->external_media_address);
|
|
}
|
|
|
|
/*! \brief Function which destroys the UDPTL instance when session ends */
|
|
static void stream_destroy(struct ast_sip_session_media *session_media)
|
|
{
|
|
if (session_media->udptl) {
|
|
ast_udptl_destroy(session_media->udptl);
|
|
}
|
|
session_media->udptl = NULL;
|
|
}
|
|
|
|
/*! \brief SDP handler for 'image' media stream */
|
|
static struct ast_sip_session_sdp_handler image_sdp_handler = {
|
|
.id = "image",
|
|
.defer_incoming_sdp_stream = defer_incoming_sdp_stream,
|
|
.negotiate_incoming_sdp_stream = negotiate_incoming_sdp_stream,
|
|
.create_outgoing_sdp_stream = create_outgoing_sdp_stream,
|
|
.apply_negotiated_sdp_stream = apply_negotiated_sdp_stream,
|
|
.change_outgoing_sdp_stream_media_address = change_outgoing_sdp_stream_media_address,
|
|
.stream_destroy = stream_destroy,
|
|
};
|
|
|
|
/*! \brief Unloads the SIP T.38 module from Asterisk */
|
|
static int unload_module(void)
|
|
{
|
|
ast_sip_session_unregister_sdp_handler(&image_sdp_handler, "image");
|
|
ast_sip_session_unregister_supplement(&t38_supplement);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*!
|
|
* \brief Load the module
|
|
*
|
|
* Module loading including tests for configuration or dependencies.
|
|
* This function can return AST_MODULE_LOAD_FAILURE, AST_MODULE_LOAD_DECLINE,
|
|
* or AST_MODULE_LOAD_SUCCESS. If a dependency or environment variable fails
|
|
* tests return AST_MODULE_LOAD_FAILURE. If the module can not load the
|
|
* configuration file or other non-critical problem return
|
|
* AST_MODULE_LOAD_DECLINE. On success return AST_MODULE_LOAD_SUCCESS.
|
|
*/
|
|
static int load_module(void)
|
|
{
|
|
CHECK_PJSIP_SESSION_MODULE_LOADED();
|
|
|
|
ast_sockaddr_parse(&address_ipv4, "0.0.0.0", 0);
|
|
ast_sockaddr_parse(&address_ipv6, "::", 0);
|
|
|
|
if (ast_sip_session_register_supplement(&t38_supplement)) {
|
|
ast_log(LOG_ERROR, "Unable to register T.38 session supplement\n");
|
|
goto end;
|
|
}
|
|
|
|
if (ast_sip_session_register_sdp_handler(&image_sdp_handler, "image")) {
|
|
ast_log(LOG_ERROR, "Unable to register SDP handler for image stream type\n");
|
|
goto end;
|
|
}
|
|
|
|
return AST_MODULE_LOAD_SUCCESS;
|
|
end:
|
|
unload_module();
|
|
|
|
return AST_MODULE_LOAD_FAILURE;
|
|
}
|
|
|
|
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "PJSIP T.38 UDPTL Support",
|
|
.support_level = AST_MODULE_SUPPORT_CORE,
|
|
.load = load_module,
|
|
.unload = unload_module,
|
|
.load_pri = AST_MODPRI_CHANNEL_DRIVER,
|
|
);
|