config_global.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 2013, Digium, Inc.
 *
 * Mark Michelson <[email protected]>
 *
 * 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.
 */

#include "asterisk.h"

#include <pjsip.h>
#include <pjlib.h>

#include "asterisk/res_pjsip.h"
#include "include/res_pjsip_private.h"
#include "asterisk/pbx.h"
#include "asterisk/sorcery.h"
#include "asterisk/taskprocessor.h"
#include "asterisk/ast_version.h"
#include "asterisk/res_pjsip_cli.h"

#define DEFAULT_MAX_FORWARDS 70
#define DEFAULT_KEEPALIVE_INTERVAL 90
#define DEFAULT_USERAGENT_PREFIX "Asterisk PBX"
#define DEFAULT_OUTBOUND_ENDPOINT "default_outbound_endpoint"
#define DEFAULT_DEBUG "no"
#define DEFAULT_ENDPOINT_IDENTIFIER_ORDER "ip,username,anonymous"
#define DEFAULT_MAX_INITIAL_QUALIFY_TIME 0
#define DEFAULT_FROM_USER "asterisk"
#define DEFAULT_REALM "asterisk"
#define DEFAULT_REGCONTEXT ""
#define DEFAULT_CONTACT_EXPIRATION_CHECK_INTERVAL 30
#define DEFAULT_DISABLE_MULTI_DOMAIN 0
#define DEFAULT_VOICEMAIL_EXTENSION ""
#define DEFAULT_UNIDENTIFIED_REQUEST_COUNT 5
#define DEFAULT_UNIDENTIFIED_REQUEST_PERIOD 5
#define DEFAULT_UNIDENTIFIED_REQUEST_PRUNE_INTERVAL 30
#define DEFAULT_MWI_TPS_QUEUE_HIGH AST_TASKPROCESSOR_HIGH_WATER_LEVEL
#define DEFAULT_MWI_TPS_QUEUE_LOW -1
#define DEFAULT_MWI_DISABLE_INITIAL_UNSOLICITED 0
#define DEFAULT_IGNORE_URI_USER_OPTIONS 0
#define DEFAULT_USE_CALLERID_CONTACT 0
#define DEFAULT_SEND_CONTACT_STATUS_ON_UPDATE_REGISTRATION 0
#define DEFAULT_TASKPROCESSOR_OVERLOAD_TRIGGER TASKPROCESSOR_OVERLOAD_TRIGGER_GLOBAL
#define DEFAULT_NOREFERSUB 1

/*!
 * \brief Cached global config object
 *
 * \details
 * Cached so we don't have to keep asking sorcery for the config.
 * We could ask for it hundreds of times a second if not more.
 */
static AO2_GLOBAL_OBJ_STATIC(global_cfg);

static char default_useragent[256];

struct global_config {
   SORCERY_OBJECT(details);
   AST_DECLARE_STRING_FIELDS(
      AST_STRING_FIELD(useragent);
      AST_STRING_FIELD(regcontext);
      AST_STRING_FIELD(default_outbound_endpoint);
      /*! Debug logging yes|no|host */
      AST_STRING_FIELD(debug);
      /*! Order by which endpoint identifiers are checked (comma separated list) */
      AST_STRING_FIELD(endpoint_identifier_order);
      /*! User name to place in From header if there is no better option */
      AST_STRING_FIELD(default_from_user);
      /*! Default voicemail extension */
      AST_STRING_FIELD(default_voicemail_extension);
      /*! Realm to use in challenges before an endpoint is identified */
      AST_STRING_FIELD(default_realm);
   );
   /*! Value to put in Max-Forwards header */
   unsigned int max_forwards;
   /*! The interval at which to send keep alive messages to active connection-oriented transports */
   unsigned int keep_alive_interval;
   /*! The maximum time for all contacts to be qualified at startup */
   unsigned int max_initial_qualify_time;
   /*! The interval at which to check for expired contacts */
   unsigned int contact_expiration_check_interval;
   /*! Nonzero to disable multi domain support */
   unsigned int disable_multi_domain;
   /*! The maximum number of unidentified requests per source IP address before a security event is logged */
   unsigned int unidentified_request_count;
   /*! The period during which unidentified requests are accumulated */
   unsigned int unidentified_request_period;
   /*! Interval at which expired unidentifed requests will be pruned */
   unsigned int unidentified_request_prune_interval;
   struct {
      /*! Taskprocessor high water alert trigger level */
      unsigned int tps_queue_high;
      /*! Taskprocessor low water clear alert level. */
      int tps_queue_low;
      /*! Nonzero to disable sending unsolicited mwi to all endpoints on startup */
      unsigned int disable_initial_unsolicited;
   } mwi;
   /*! Nonzero if URI user field options are ignored. */
   unsigned int ignore_uri_user_options;
   /*! Nonzero if CALLERID(num) is to be used as the default contact username instead of default_from_user */
   unsigned int use_callerid_contact;
   /*! Nonzero if need to send AMI ContactStatus event when a contact is updated */
   unsigned int send_contact_status_on_update_registration;
   /*! Trigger the distributor should use to pause accepting new dialogs */
   enum ast_sip_taskprocessor_overload_trigger overload_trigger;
   /*! Nonzero if norefersub is to be sent in Supported header */
   unsigned int norefersub;
};

static void global_destructor(void *obj)
{
   struct global_config *cfg = obj;

   ast_string_field_free_memory(cfg);
}

static void *global_alloc(const char *name)
{
   struct global_config *cfg;

   cfg = ast_sorcery_generic_alloc(sizeof(*cfg), global_destructor);
   if (!cfg || ast_string_field_init(cfg, 100)) {
      ao2_cleanup(cfg);
      return NULL;
   }

   return cfg;
}

/*
 * There is ever only one global section, so we can use a single global
 * value here to track the regcontext through reloads.
 */
static char *previous_regcontext = NULL;

static int check_regcontext(const struct global_config *cfg)
{
   char *current = NULL;

   if (previous_regcontext && !strcmp(previous_regcontext, cfg->regcontext)) {
      /* Nothing changed so nothing to do */
      return 0;
   }

   if (!ast_strlen_zero(cfg->regcontext)) {
      current = ast_strdup(cfg->regcontext);
      if (!current) {
         return -1;
      }

      if (ast_sip_persistent_endpoint_add_to_regcontext(cfg->regcontext)) {
         ast_free(current);
         return -1;
      }
   }

   if (!ast_strlen_zero(previous_regcontext)) {
      ast_context_destroy_by_name(previous_regcontext, "PJSIP");
      ast_free(previous_regcontext);
      previous_regcontext = NULL;
   }

   if (current) {
      previous_regcontext = current;
   }

   return 0;
}

static int global_apply(const struct ast_sorcery *sorcery, void *obj)
{
   struct global_config *cfg = obj;
   char max_forwards[10];

   if (ast_strlen_zero(cfg->debug)) {
      ast_log(LOG_ERROR,
         "Global option 'debug' can't be empty.  Set it to a valid value or remove the entry to accept 'no' as the default\n");
      return -1;
   }

   if (ast_strlen_zero(cfg->default_from_user)) {
      ast_log(LOG_ERROR,
         "Global option 'default_from_user' can't be empty.  Set it to a valid value or remove the entry to accept 'asterisk' as the default\n");
      return -1;
   }

   snprintf(max_forwards, sizeof(max_forwards), "%u", cfg->max_forwards);

   ast_sip_add_global_request_header("Max-Forwards", max_forwards, 1);
   ast_sip_add_global_request_header("User-Agent", cfg->useragent, 1);
   ast_sip_add_global_response_header("Server", cfg->useragent, 1);

   if (check_regcontext(cfg)) {
      return -1;
   }

   ao2_t_global_obj_replace_unref(global_cfg, cfg, "Applying global settings");
   return 0;
}

static struct global_config *get_global_cfg(void)
{
   return ao2_global_obj_ref(global_cfg);
}

char *ast_sip_global_default_outbound_endpoint(void)
{
   char *str;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return ast_strdup(DEFAULT_OUTBOUND_ENDPOINT);
   }

   str = ast_strdup(cfg->default_outbound_endpoint);
   ao2_ref(cfg, -1);
   return str;
}

char *ast_sip_get_debug(void)
{
   char *res;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return ast_strdup(DEFAULT_DEBUG);
   }

   res = ast_strdup(cfg->debug);
   ao2_ref(cfg, -1);
   return res;
}

char *ast_sip_get_regcontext(void)
{
   char *res;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return ast_strdup(DEFAULT_REGCONTEXT);
   }

   res = ast_strdup(cfg->regcontext);
   ao2_ref(cfg, -1);

   return res;
}

char *ast_sip_get_default_voicemail_extension(void)
{
   char *res;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return ast_strdup(DEFAULT_VOICEMAIL_EXTENSION);
   }

   res = ast_strdup(cfg->default_voicemail_extension);
   ao2_ref(cfg, -1);

   return res;
}

char *ast_sip_get_endpoint_identifier_order(void)
{
   char *res;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return ast_strdup(DEFAULT_ENDPOINT_IDENTIFIER_ORDER);
   }

   res = ast_strdup(cfg->endpoint_identifier_order);
   ao2_ref(cfg, -1);
   return res;
}

unsigned int ast_sip_get_keep_alive_interval(void)
{
   unsigned int interval;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return DEFAULT_KEEPALIVE_INTERVAL;
   }

   interval = cfg->keep_alive_interval;
   ao2_ref(cfg, -1);
   return interval;
}

unsigned int ast_sip_get_contact_expiration_check_interval(void)
{
   unsigned int interval;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return DEFAULT_CONTACT_EXPIRATION_CHECK_INTERVAL;
   }

   interval = cfg->contact_expiration_check_interval;
   ao2_ref(cfg, -1);
   return interval;
}

unsigned int ast_sip_get_disable_multi_domain(void)
{
   unsigned int disable_multi_domain;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return DEFAULT_DISABLE_MULTI_DOMAIN;
   }

   disable_multi_domain = cfg->disable_multi_domain;
   ao2_ref(cfg, -1);
   return disable_multi_domain;
}

unsigned int ast_sip_get_max_initial_qualify_time(void)
{
   unsigned int time;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return DEFAULT_MAX_INITIAL_QUALIFY_TIME;
   }

   time = cfg->max_initial_qualify_time;
   ao2_ref(cfg, -1);
   return time;
}

void ast_sip_get_unidentified_request_thresholds(unsigned int *count, unsigned int *period,
   unsigned int *prune_interval)
{
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      *count = DEFAULT_UNIDENTIFIED_REQUEST_COUNT;
      *period = DEFAULT_UNIDENTIFIED_REQUEST_PERIOD;
      *prune_interval = DEFAULT_UNIDENTIFIED_REQUEST_PRUNE_INTERVAL;
      return;
   }

   *count = cfg->unidentified_request_count;
   *period = cfg->unidentified_request_period;
   *prune_interval = cfg->unidentified_request_prune_interval;

   ao2_ref(cfg, -1);
   return;
}

void ast_sip_get_default_realm(char *realm, size_t size)
{
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      ast_copy_string(realm, DEFAULT_REALM, size);
   } else {
      ast_copy_string(realm, cfg->default_realm, size);
      ao2_ref(cfg, -1);
   }
}

void ast_sip_get_default_from_user(char *from_user, size_t size)
{
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      ast_copy_string(from_user, DEFAULT_FROM_USER, size);
   } else {
      ast_copy_string(from_user, cfg->default_from_user, size);
      ao2_ref(cfg, -1);
   }
}


unsigned int ast_sip_get_mwi_tps_queue_high(void)
{
   unsigned int tps_queue_high;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return DEFAULT_MWI_TPS_QUEUE_HIGH;
   }

   tps_queue_high = cfg->mwi.tps_queue_high;
   ao2_ref(cfg, -1);
   return tps_queue_high;
}

int ast_sip_get_mwi_tps_queue_low(void)
{
   int tps_queue_low;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return DEFAULT_MWI_TPS_QUEUE_LOW;
   }

   tps_queue_low = cfg->mwi.tps_queue_low;
   ao2_ref(cfg, -1);
   return tps_queue_low;
}

unsigned int ast_sip_get_mwi_disable_initial_unsolicited(void)
{
   unsigned int disable_initial_unsolicited;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return DEFAULT_MWI_DISABLE_INITIAL_UNSOLICITED;
   }

   disable_initial_unsolicited = cfg->mwi.disable_initial_unsolicited;
   ao2_ref(cfg, -1);
   return disable_initial_unsolicited;
}

unsigned int ast_sip_get_ignore_uri_user_options(void)
{
   unsigned int ignore_uri_user_options;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return DEFAULT_IGNORE_URI_USER_OPTIONS;
   }

   ignore_uri_user_options = cfg->ignore_uri_user_options;
   ao2_ref(cfg, -1);
   return ignore_uri_user_options;
}

unsigned int ast_sip_get_use_callerid_contact(void)
{
   unsigned int use_callerid_contact;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return DEFAULT_USE_CALLERID_CONTACT;
   }

   use_callerid_contact = cfg->use_callerid_contact;
   ao2_ref(cfg, -1);
   return use_callerid_contact;
}

unsigned int ast_sip_get_send_contact_status_on_update_registration(void)
{
   unsigned int send_contact_status_on_update_registration;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return DEFAULT_SEND_CONTACT_STATUS_ON_UPDATE_REGISTRATION;
   }

   send_contact_status_on_update_registration = cfg->send_contact_status_on_update_registration;
   ao2_ref(cfg, -1);
   return send_contact_status_on_update_registration;
}

enum ast_sip_taskprocessor_overload_trigger ast_sip_get_taskprocessor_overload_trigger(void)
{
   enum ast_sip_taskprocessor_overload_trigger trigger;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return DEFAULT_TASKPROCESSOR_OVERLOAD_TRIGGER;
   }

   trigger = cfg->overload_trigger;
   ao2_ref(cfg, -1);
   return trigger;
}

unsigned int ast_sip_get_norefersub(void)
{
   unsigned int norefersub;
   struct global_config *cfg;

   cfg = get_global_cfg();
   if (!cfg) {
      return DEFAULT_NOREFERSUB;
   }

   norefersub = cfg->norefersub;
   ao2_ref(cfg, -1);
   return norefersub;
}

static int overload_trigger_handler(const struct aco_option *opt,
   struct ast_variable *var, void *obj)
{
   struct global_config *cfg = obj;
   if (!strcasecmp(var->value, "none")) {
      cfg->overload_trigger = TASKPROCESSOR_OVERLOAD_TRIGGER_NONE;
   } else if (!strcasecmp(var->value, "global")) {
      cfg->overload_trigger = TASKPROCESSOR_OVERLOAD_TRIGGER_GLOBAL;
   } else if (!strcasecmp(var->value, "pjsip_only")) {
      cfg->overload_trigger = TASKPROCESSOR_OVERLOAD_TRIGGER_PJSIP_ONLY;
   } else {
      ast_log(LOG_WARNING, "Unknown overload trigger '%s' specified for %s\n",
            var->value, var->name);
      return -1;
   }
   return 0;
}

static const char *overload_trigger_map[] = {
   [TASKPROCESSOR_OVERLOAD_TRIGGER_NONE] = "none",
   [TASKPROCESSOR_OVERLOAD_TRIGGER_GLOBAL] = "global",
   [TASKPROCESSOR_OVERLOAD_TRIGGER_PJSIP_ONLY] = "pjsip_only"
};

const char *ast_sip_overload_trigger_to_str(enum ast_sip_taskprocessor_overload_trigger trigger)
{
   return ARRAY_IN_BOUNDS(trigger, overload_trigger_map) ?
      overload_trigger_map[trigger] : "";
}

static int overload_trigger_to_str(const void *obj, const intptr_t *args, char **buf)
{
   const struct global_config *cfg = obj;
   *buf = ast_strdup(ast_sip_overload_trigger_to_str(cfg->overload_trigger));
   return 0;
}

/*!
 * \internal
 * \brief Observer to set default global object if none exist.
 *
 * \param name Module name owning the sorcery instance.
 * \param sorcery Instance being observed.
 * \param object_type Name of object being observed.
 * \param reloaded Non-zero if the object is being reloaded.
 *
 * \return Nothing
 */
static void global_loaded_observer(const char *name, const struct ast_sorcery *sorcery, const char *object_type, int reloaded)
{
   struct ao2_container *globals;
   struct global_config *cfg;

   if (strcmp(object_type, "global")) {
      /* Not interested */
      return;
   }

   globals = ast_sorcery_retrieve_by_fields(sorcery, "global",
      AST_RETRIEVE_FLAG_MULTIPLE | AST_RETRIEVE_FLAG_ALL, NULL);
   if (globals) {
      int count;

      count = ao2_container_count(globals);
      ao2_ref(globals, -1);

      if (1 < count) {
         ast_log(LOG_ERROR,
            "At most one pjsip.conf type=global object can be defined.  You have %d defined.\n",
            count);
         return;
      }
      if (count) {
         return;
      }
   }

   ast_debug(1, "No pjsip.conf type=global object exists so applying defaults.\n");
   cfg = ast_sorcery_alloc(sorcery, "global", NULL);
   if (!cfg) {
      return;
   }
   global_apply(sorcery, cfg);
   ao2_ref(cfg, -1);
}

static const struct ast_sorcery_instance_observer observer_callbacks_global = {
   .object_type_loaded = global_loaded_observer,
};

int sip_cli_print_global(struct ast_sip_cli_context *context)
{
   struct global_config *cfg = get_global_cfg();

   if (!cfg) {
      cfg = ast_sorcery_alloc(ast_sip_get_sorcery(), "global", NULL);
      if (!cfg) {
         return -1;
      }
   }

   ast_str_append(&context->output_buffer, 0, "\nGlobal Settings:\n\n");
   ast_sip_cli_print_sorcery_objectset(cfg, context, 0);

   ao2_ref(cfg, -1);
   return 0;
}

int ast_sip_destroy_sorcery_global(void)
{
   struct ast_sorcery *sorcery = ast_sip_get_sorcery();

   ast_sorcery_instance_observer_remove(sorcery, &observer_callbacks_global);

   if (previous_regcontext) {
      ast_context_destroy_by_name(previous_regcontext, "PJSIP");
      ast_free(previous_regcontext);
   }

   ao2_t_global_obj_release(global_cfg, "Module is unloading");

   return 0;
}


int ast_sip_initialize_sorcery_global(void)
{
   struct ast_sorcery *sorcery = ast_sip_get_sorcery();

   snprintf(default_useragent, sizeof(default_useragent), "%s %s",
      DEFAULT_USERAGENT_PREFIX, ast_get_version());

   ast_sorcery_apply_default(sorcery, "global", "config", "pjsip.conf,criteria=type=global,single_object=yes,explicit_name=global");

   if (ast_sorcery_object_register(sorcery, "global", global_alloc, NULL, global_apply)) {
      return -1;
   }

   ast_sorcery_object_field_register(sorcery, "global", "type", "", OPT_NOOP_T, 0, 0);
   ast_sorcery_object_field_register(sorcery, "global", "max_forwards",
      __stringify(DEFAULT_MAX_FORWARDS),
      OPT_UINT_T, 0, FLDSET(struct global_config, max_forwards));
   ast_sorcery_object_field_register(sorcery, "global", "user_agent", default_useragent,
      OPT_STRINGFIELD_T, 0, STRFLDSET(struct global_config, useragent));
   ast_sorcery_object_field_register(sorcery, "global", "default_outbound_endpoint",
      DEFAULT_OUTBOUND_ENDPOINT,
      OPT_STRINGFIELD_T, 0, STRFLDSET(struct global_config, default_outbound_endpoint));
   ast_sorcery_object_field_register(sorcery, "global", "debug", DEFAULT_DEBUG,
      OPT_STRINGFIELD_T, 0, STRFLDSET(struct global_config, debug));
   ast_sorcery_object_field_register(sorcery, "global", "endpoint_identifier_order",
      DEFAULT_ENDPOINT_IDENTIFIER_ORDER,
      OPT_STRINGFIELD_T, 0, STRFLDSET(struct global_config, endpoint_identifier_order));
   ast_sorcery_object_field_register(sorcery, "global", "keep_alive_interval",
      __stringify(DEFAULT_KEEPALIVE_INTERVAL),
      OPT_UINT_T, 0, FLDSET(struct global_config, keep_alive_interval));
   ast_sorcery_object_field_register(sorcery, "global", "max_initial_qualify_time",
      __stringify(DEFAULT_MAX_INITIAL_QUALIFY_TIME),
      OPT_UINT_T, 0, FLDSET(struct global_config, max_initial_qualify_time));
   ast_sorcery_object_field_register(sorcery, "global", "default_from_user", DEFAULT_FROM_USER,
      OPT_STRINGFIELD_T, 0, STRFLDSET(struct global_config, default_from_user));
   ast_sorcery_object_field_register(sorcery, "global", "default_voicemail_extension",
      DEFAULT_VOICEMAIL_EXTENSION, OPT_STRINGFIELD_T, 0, STRFLDSET(struct global_config,
      default_voicemail_extension));
   ast_sorcery_object_field_register(sorcery, "global", "regcontext", DEFAULT_REGCONTEXT,
      OPT_STRINGFIELD_T, 0, STRFLDSET(struct global_config, regcontext));
   ast_sorcery_object_field_register(sorcery, "global", "contact_expiration_check_interval",
      __stringify(DEFAULT_CONTACT_EXPIRATION_CHECK_INTERVAL),
      OPT_UINT_T, 0, FLDSET(struct global_config, contact_expiration_check_interval));
   ast_sorcery_object_field_register(sorcery, "global", "disable_multi_domain",
      DEFAULT_DISABLE_MULTI_DOMAIN ? "yes" : "no",
      OPT_BOOL_T, 1, FLDSET(struct global_config, disable_multi_domain));
   ast_sorcery_object_field_register(sorcery, "global", "unidentified_request_count",
      __stringify(DEFAULT_UNIDENTIFIED_REQUEST_COUNT),
      OPT_UINT_T, 0, FLDSET(struct global_config, unidentified_request_count));
   ast_sorcery_object_field_register(sorcery, "global", "unidentified_request_period",
      __stringify(DEFAULT_UNIDENTIFIED_REQUEST_PERIOD),
      OPT_UINT_T, 0, FLDSET(struct global_config, unidentified_request_period));
   ast_sorcery_object_field_register(sorcery, "global", "unidentified_request_prune_interval",
      __stringify(DEFAULT_UNIDENTIFIED_REQUEST_PRUNE_INTERVAL),
      OPT_UINT_T, 0, FLDSET(struct global_config, unidentified_request_prune_interval));
   ast_sorcery_object_field_register(sorcery, "global", "default_realm", DEFAULT_REALM,
      OPT_STRINGFIELD_T, 0, STRFLDSET(struct global_config, default_realm));
   ast_sorcery_object_field_register(sorcery, "global", "mwi_tps_queue_high",
      __stringify(DEFAULT_MWI_TPS_QUEUE_HIGH),
      OPT_UINT_T, 0, FLDSET(struct global_config, mwi.tps_queue_high));
   ast_sorcery_object_field_register(sorcery, "global", "mwi_tps_queue_low",
      __stringify(DEFAULT_MWI_TPS_QUEUE_LOW),
      OPT_INT_T, 0, FLDSET(struct global_config, mwi.tps_queue_low));
   ast_sorcery_object_field_register(sorcery, "global", "mwi_disable_initial_unsolicited",
      DEFAULT_MWI_DISABLE_INITIAL_UNSOLICITED ? "yes" : "no",
      OPT_BOOL_T, 1, FLDSET(struct global_config, mwi.disable_initial_unsolicited));
   ast_sorcery_object_field_register(sorcery, "global", "ignore_uri_user_options",
      DEFAULT_IGNORE_URI_USER_OPTIONS ? "yes" : "no",
      OPT_BOOL_T, 1, FLDSET(struct global_config, ignore_uri_user_options));
   ast_sorcery_object_field_register(sorcery, "global", "use_callerid_contact",
      DEFAULT_USE_CALLERID_CONTACT ? "yes" : "no",
      OPT_YESNO_T, 1, FLDSET(struct global_config, use_callerid_contact));
   ast_sorcery_object_field_register(sorcery, "global", "send_contact_status_on_update_registration",
      DEFAULT_SEND_CONTACT_STATUS_ON_UPDATE_REGISTRATION ? "yes" : "no",
      OPT_YESNO_T, 1, FLDSET(struct global_config, send_contact_status_on_update_registration));
   ast_sorcery_object_field_register_custom(sorcery, "global", "taskprocessor_overload_trigger",
      overload_trigger_map[DEFAULT_TASKPROCESSOR_OVERLOAD_TRIGGER],
      overload_trigger_handler, overload_trigger_to_str, NULL, 0, 0);
   ast_sorcery_object_field_register(sorcery, "global", "norefersub",
      DEFAULT_NOREFERSUB ? "yes" : "no",
      OPT_YESNO_T, 1, FLDSET(struct global_config, norefersub));

   if (ast_sorcery_instance_observer_add(sorcery, &observer_callbacks_global)) {
      return -1;
   }

   return 0;
}