res_pjsip_dialog_info_body_generator.c

Go to the documentation of this file.

/*
 * asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2014, Digium, Inc.
 *
 * Joshua Colp <jcolp@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */
 
/*** MODULEINFO
    <depend>pjproject</depend>
    <depend>res_pjsip</depend>
    <depend>res_pjsip_pubsub</depend>
    <support_level>core</support_level>
 ***/
 
#include "asterisk.h"
 
#include <pjsip.h>
#include <pjsip_simple.h>
#include <pjlib.h>
 
#include "asterisk/module.h"
#include "asterisk/callerid.h"
#include "asterisk/res_pjsip.h"
#include "asterisk/res_pjsip_pubsub.h"
#include "asterisk/res_pjsip_presence_xml.h"
#include "asterisk/res_pjsip_body_generator_types.h"
 
/*! \brief Structure which contains dialog-info+xml state information */
struct dialog_info_xml_state {
    /*! \brief Version to place into the next NOTIFY */
    unsigned int version;
};
 
/*! \brief Destructor for dialog-info+xml information */
static void dialog_info_xml_state_destroy(void *obj)
{
    ast_free(obj);
}
 
/*! \brief Datastore for attaching dialog-info+xml state information */
static const struct ast_datastore_info dialog_info_xml_datastore = {
    .type = "dialog-info+xml",
    .destroy = dialog_info_xml_state_destroy,
};
 
static void *dialog_info_allocate_body(void *data)
{
    struct ast_sip_exten_state_data *state_data = data;
 
    return ast_sip_presence_xml_create_node(state_data->pool, NULL, "dialog-info");
}
 
/*!
 * \internal
 * \brief Find the channel that is causing the RINGING update, ref'd
 */
static struct ast_channel *find_ringing_channel(struct ao2_container *device_state_info)
{
    struct ao2_iterator citer;
    struct ast_device_state_info *device_state;
    struct ast_channel *c = NULL;
    struct timeval tv = {0,};
 
    /* iterate ringing devices and get the oldest of all causing channels */
    citer = ao2_iterator_init(device_state_info, 0);
    for (; (device_state = ao2_iterator_next(&citer)); ao2_ref(device_state, -1)) {
        if (!device_state->causing_channel || (device_state->device_state != AST_DEVICE_RINGING &&
                device_state->device_state != AST_DEVICE_RINGINUSE)) {
            continue;
        }
        ast_channel_lock(device_state->causing_channel);
        if (ast_tvzero(tv) || ast_tvcmp(ast_channel_creationtime(device_state->causing_channel), tv) < 0) {
            c = device_state->causing_channel;
            tv = ast_channel_creationtime(c);
        }
        ast_channel_unlock(device_state->causing_channel);
    }
    ao2_iterator_destroy(&citer);
    return c ? ast_channel_ref(c) : NULL;
}
 
static int dialog_info_generate_body_content(void *body, void *data)
{
    pj_xml_node *dialog_info = body, *dialog, *state;
    struct ast_datastore *datastore;
    struct dialog_info_xml_state *datastore_state;
    struct ast_sip_exten_state_data *state_data = data;
    char *local = ast_strdupa(state_data->local), *stripped, *statestring = NULL;
    char *remote = ast_strdupa(state_data->remote);
    char *pidfstate = NULL, *pidfnote = NULL;
    enum ast_sip_pidf_state local_state;
    char version_str[32], sanitized[PJSIP_MAX_URL_SIZE];
    struct ast_sip_endpoint *endpoint = NULL;
    unsigned int notify_early_inuse_ringing = 0;
 
    if (!local || !remote || !state_data->datastores) {
        return -1;
    }
 
    datastore = ast_datastores_find(state_data->datastores, "dialog-info+xml");
    if (!datastore) {
        const struct ast_json *version_json = NULL;
 
        datastore = ast_datastores_alloc_datastore(&dialog_info_xml_datastore, "dialog-info+xml");
        if (!datastore) {
            return -1;
        }
 
        datastore->data = ast_calloc(1, sizeof(struct dialog_info_xml_state));
        if (!datastore->data || ast_datastores_add(state_data->datastores, datastore)) {
            ao2_ref(datastore, -1);
            return -1;
        }
        datastore_state = datastore->data;
 
        if (state_data->sub) {
            version_json = ast_sip_subscription_get_persistence_data(state_data->sub);
        }
 
        if (version_json) {
            datastore_state->version = ast_json_integer_get(version_json);
            datastore_state->version++;
        } else {
            datastore_state->version = 0;
        }
    } else {
        datastore_state = datastore->data;
        datastore_state->version++;
    }
 
    stripped = ast_strip_quoted(local, "<", ">");
    ast_sip_sanitize_xml(stripped, sanitized, sizeof(sanitized));
 
    if (state_data->sub && (endpoint = ast_sip_subscription_get_endpoint(state_data->sub))) {
        notify_early_inuse_ringing = endpoint->notify_early_inuse_ringing;
        ao2_cleanup(endpoint);
    }
    ast_sip_presence_exten_state_to_str(state_data->exten_state, &statestring,
            &pidfstate, &pidfnote, &local_state, notify_early_inuse_ringing);
 
    ast_sip_presence_xml_create_attr(state_data->pool, dialog_info, "xmlns", "urn:ietf:params:xml:ns:dialog-info");
 
    snprintf(version_str, sizeof(version_str), "%u", datastore_state->version);
    ast_sip_presence_xml_create_attr(state_data->pool, dialog_info, "version", version_str);
 
    if (state_data->sub) {
        ast_sip_subscription_set_persistence_data(state_data->sub, ast_json_integer_create(datastore_state->version));
    }
 
    ast_sip_presence_xml_create_attr(state_data->pool, dialog_info, "state", "full");
    ast_sip_presence_xml_create_attr(state_data->pool, dialog_info, "entity", sanitized);
 
    dialog = ast_sip_presence_xml_create_node(state_data->pool, dialog_info, "dialog");
    ast_sip_presence_xml_create_attr(state_data->pool, dialog, "id", state_data->exten);
    if (!ast_strlen_zero(statestring) && !strcmp(statestring, "early")) {
        struct ast_channel *callee = NULL;
        char local_target[PJSIP_MAX_URL_SIZE + 32] = "";
        char *local_cid_name = NULL;
        pj_xml_node *local_node, *local_identity_node, *local_target_node;
 
        ast_sip_presence_xml_create_attr(state_data->pool, dialog, "direction", "recipient");
 
        if (state_data->device_state_info) {
            callee = find_ringing_channel(state_data->device_state_info);
        }
 
        if (callee) {
            static char *anonymous = "anonymous";
            static char *invalid = "anonymous.invalid";
            char *remote_cid_name;
            char *remote_connected_num;
            int remote_connected_num_restricted;
            char *local_caller_num;
            pjsip_dialog *dlg = ast_sip_subscription_get_dialog(state_data->sub);
            char remote_target[PJSIP_MAX_URL_SIZE + 32];
            char dlg_remote_uri[PJSIP_MAX_URL_SIZE];
            char *from_domain_stripped;
            char from_domain_sanitized[PJSIP_MAX_URL_SIZE];
            pj_xml_node *remote_node, *remote_identity_node, *remote_target_node;
 
            /* We use the local dialog URI to determine the domain to use in the XML itself */
            ast_copy_pj_str(dlg_remote_uri, ast_sip_pjsip_uri_get_hostname(dlg->local.info->uri), sizeof(dlg_remote_uri));
            from_domain_stripped = ast_strip_quoted(dlg_remote_uri, "<", ">");
            ast_sip_sanitize_xml(from_domain_stripped, from_domain_sanitized, sizeof(from_domain_sanitized));
 
            ast_channel_lock(callee);
 
            /* The remote node uses the connected line information, so who is calling the
             * monitored endpoint.
             */
            remote_cid_name = S_COR(ast_channel_connected(callee)->id.name.valid,
                S_COR((ast_channel_connected(callee)->id.name.presentation &
                        AST_PRES_RESTRICTION) == AST_PRES_RESTRICTED, anonymous,
                    ast_channel_connected(callee)->id.name.str), "");
 
            remote_connected_num_restricted = (ast_channel_connected(callee)->id.number.presentation &
                AST_PRES_RESTRICTION) == AST_PRES_RESTRICTED;
            remote_connected_num = S_COR(ast_channel_connected(callee)->id.number.valid,
                S_COR(remote_connected_num_restricted, anonymous,
                    ast_channel_connected(callee)->id.number.str), "invalid");
 
            snprintf(remote_target, sizeof(remote_target), "sip:%s@%s", remote_connected_num,
                remote_connected_num_restricted ? invalid : from_domain_sanitized);
 
            /* The local node uses the callerid information, so what the callerid would be
             * if the monitored endpoint was calling.
             */
            local_cid_name = S_COR(ast_channel_caller(callee)->id.name.valid,
                ast_channel_caller(callee)->id.name.str, "");
            local_caller_num = S_COR(ast_channel_caller(callee)->id.number.valid,
                ast_channel_caller(callee)->id.number.str, "invalid");
 
            snprintf(local_target, sizeof(local_target), "sip:%s@%s", local_caller_num,
                from_domain_sanitized);
 
            ast_channel_unlock(callee);
            callee = ast_channel_unref(callee);
 
            remote_node = ast_sip_presence_xml_create_node(state_data->pool, dialog, "remote");
            remote_identity_node = ast_sip_presence_xml_create_node(state_data->pool, remote_node, "identity");
            remote_target_node = ast_sip_presence_xml_create_node(state_data->pool, remote_node, "target");
 
            pj_strdup2(state_data->pool, &remote_identity_node->content, remote_target);
            if (!ast_strlen_zero(remote_cid_name)) {
                char display_sanitized[PJSIP_MAX_URL_SIZE];
 
                ast_sip_sanitize_xml(remote_cid_name, display_sanitized, sizeof(display_sanitized));
                ast_sip_presence_xml_create_attr(state_data->pool, remote_identity_node, "display", display_sanitized);
            }
            ast_sip_presence_xml_create_attr(state_data->pool, remote_target_node, "uri", remote_target);
        }
 
        if (state_data->device_state_info) {
            local_node = ast_sip_presence_xml_create_node(state_data->pool, dialog, "local");
            local_identity_node = ast_sip_presence_xml_create_node(state_data->pool, local_node, "identity");
            local_target_node = ast_sip_presence_xml_create_node(state_data->pool, local_node, "target");
 
            /* If a channel is not available we fall back to the sanitized local URI instead */
            pj_strdup2(state_data->pool, &local_identity_node->content, S_OR(local_target, sanitized));
            if (!ast_strlen_zero(local_cid_name)) {
                char display_sanitized[PJSIP_MAX_URL_SIZE];
 
                ast_sip_sanitize_xml(local_cid_name, display_sanitized, sizeof(display_sanitized));
                ast_sip_presence_xml_create_attr(state_data->pool, local_identity_node, "display", display_sanitized);
            }
 
            ast_sip_presence_xml_create_attr(state_data->pool, local_target_node, "uri", sanitized);
        }
    }
 
    state = ast_sip_presence_xml_create_node(state_data->pool, dialog, "state");
    pj_strdup2(state_data->pool, &state->content, statestring);
 
    if (state_data->exten_state == AST_EXTENSION_ONHOLD) {
        pj_xml_node *local_node, *target, *param;
 
        local_node = ast_sip_presence_xml_create_node(state_data->pool, dialog, "local");
        target = ast_sip_presence_xml_create_node(state_data->pool, local_node, "target");
        ast_sip_presence_xml_create_attr(state_data->pool, target, "uri", sanitized);
        param = ast_sip_presence_xml_create_node(state_data->pool, target, "param");
        ast_sip_presence_xml_create_attr(state_data->pool, param, "pname", "+sip.rendering");
        ast_sip_presence_xml_create_attr(state_data->pool, param, "pvalue", "no");
    }
 
    ao2_ref(datastore, -1);
 
    return 0;
}
 
/* The maximum number of times the ast_str() for the body text can grow before we declare an XML body
 * too large to send.
 */
#define MAX_STRING_GROWTHS 6
 
static void dialog_info_to_string(void *body, struct ast_str **str)
{
    pj_xml_node *dialog_info = body;
    int growths = 0;
    int size;
 
    do {
        size = pj_xml_print(dialog_info, ast_str_buffer(*str), ast_str_size(*str) - 1, PJ_TRUE);
        if (size <= AST_PJSIP_XML_PROLOG_LEN) {
            ast_str_make_space(str, ast_str_size(*str) * 2);
            ++growths;
        }
    } while (size <= AST_PJSIP_XML_PROLOG_LEN && growths < MAX_STRING_GROWTHS);
    if (size <= AST_PJSIP_XML_PROLOG_LEN) {
        ast_log(LOG_WARNING, "dialog-info+xml body text too large\n");
        return;
    }
 
    *(ast_str_buffer(*str) + size) = '\0';
    ast_str_update(*str);
}
 
static struct ast_sip_pubsub_body_generator dialog_info_body_generator = {
    .type = "application",
    .subtype = "dialog-info+xml",
    .body_type = AST_SIP_EXTEN_STATE_DATA,
    .allocate_body = dialog_info_allocate_body,
    .generate_body_content = dialog_info_generate_body_content,
    .to_string = dialog_info_to_string,
    /* No need for a destroy_body callback since we use a pool */
};
 
static int load_module(void)
{
    if (ast_sip_pubsub_register_body_generator(&dialog_info_body_generator)) {
        return AST_MODULE_LOAD_DECLINE;
    }
 
    return AST_MODULE_LOAD_SUCCESS;
}
 
static int unload_module(void)
{
    ast_sip_pubsub_unregister_body_generator(&dialog_info_body_generator);
    return 0;
}
 
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "PJSIP Extension State Dialog Info+XML Provider",
    .support_level = AST_MODULE_SUPPORT_CORE,
    .load = load_module,
    .unload = unload_module,
    .load_pri = AST_MODPRI_CHANNEL_DEPEND,
    .requires = "res_pjsip,res_pjsip_pubsub",
);